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Sample records for science reasoning sub-test

  1. ANALYSIS OF STUDENTS’ DECISION MAKING TO SOLVE SCIENCE REASONING TEST OF TRENDS IN INTERNATIONAL MATHEMATICS AND SCIENCE STUDY (TIMSS

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    N. Novianawati

    2015-04-01

    Full Text Available This study aims to determine students’ decision making strategy to answer TIMSS science reasoning test in cognitive reasoning domain. This research is quantitative descriptive research. The result shows that students tend to use compensatory strategy for decision making in solving multiple-choice questions and use rational category to answer essay questions. The result shows that more than half of students have been able to answer the questions TIMSS science tests correctly.

  2. Investigating the Correlation Between Pharmacy Student Performance on the Health Science Reasoning Test and a Critical Thinking Assignment

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    Nornoo, Adwoa O.; Jackson, Jonathan; Axtell, Samantha

    2017-01-01

    Objective. To determine whether there is a correlation between pharmacy students? scores on the Health Science Reasoning Test (HSRT) and their grade on a package insert assignment designed to assess critical thinking.

  3. Reasoning about logical propositions and success in science

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    Piburn, Michael D.

    1990-12-01

    Students display a number of misconceptions when asked to reason about logical propositions. Rather than being random, these misconceptions are stereotypic, and relate to age, ability, and success in science. The grades in science achieved by tenth-grade general science students from two parochial single-sex schools in Australia correlated with their scores on the Propositional Logic Test. The students' ability level was consistently related to the pattern of errors they committed on that measure. Mean scores were lowest on a subtest of ability to use the biconditional and implication, higher on the disjunction, and highest on the conjunction. Success in science was predicted most strongly by the disjunction and biconditional subtests. Knowledge of the way in which a person reasons about logical propositions provides additional insights into the transformations information is subjected to as it is integrated into mental schemata.

  4. The nature of advanced reasoning and science instruction

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    Lawson, Anton E.

    Although the development of reasoning is recognized as an important goal of science instruction, its nature remains somewhat of a mystery. This article discusses two key questions: Does formal thought constitute a structured whole? And what role does propositional logic play in advanced reasoning? Aspects of a model of advanced reasoning are presented in which hypothesis generation and testing are viewed as central processes in intellectual development. It is argued that a number of important advanced reasoning schemata are linked by these processes and should be made a part of science instruction designed to improve students' reasoning abilities.Concerning students' development and use of formal reasoning, Linn (1982) calls for research into practical issues such as the roles of task-specific knowledge and individual differences in performance, roles not emphasized by Piaget in his theory and research. From a science teacher's point of view, this is good advice. Accordingly, this article will expand upon some of the issues raised by Linn in a discussion of the nature of advanced reasoning which attempts to reconcile the apparent contradiction between students' differential use of advanced reasoning schemata in varying contexts with the notion of a general stage of formal thought. Two key questions will be discussed: Does formal thought constitute a structured whole? And what role does propositional logic play in advanced reasoning? The underlying assumption of the present discussion is that, among other things, science instruction should concern itself with the improvement of students' reasoning abilities (cf. Arons, 1976; Arons & Karplus, 1976; Bady, 1979; Bauman, 1976; Educational Policies Commission, 1966; Herron, 1978; Karplus, 1979; Kohlberg & Mayer, 1972; Moshman & Thompson, 1981; Lawson, 1979; Levine & linn, 1977; Pallrand, 1977; Renner & Lawson, 1973; Sayre & Ball, 1975; Schneider & Renner, 1980; Wollman, 1978). The questions are of interest because to

  5. Puzzle test: A tool for non-analytical clinical reasoning assessment.

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    Monajemi, Alireza; Yaghmaei, Minoo

    2016-01-01

    Most contemporary clinical reasoning tests typically assess non-automatic thinking. Therefore, a test is needed to measure automatic reasoning or pattern recognition, which has been largely neglected in clinical reasoning tests. The Puzzle Test (PT) is dedicated to assess automatic clinical reasoning in routine situations. This test has been introduced first in 2009 by Monajemi et al in the Olympiad for Medical Sciences Students.PT is an item format that has gained acceptance in medical education, but no detailed guidelines exist for this test's format, construction and scoring. In this article, a format is described and the steps to prepare and administer valid and reliable PTs are presented. PT examines a specific clinical reasoning task: Pattern recognition. PT does not replace other clinical reasoning assessment tools. However, it complements them in strategies for assessing comprehensive clinical reasoning.

  6. Association of Health Sciences Reasoning Test scores with academic and experiential performance.

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    Cox, Wendy C; McLaughlin, Jacqueline E

    2014-05-15

    To assess the association of scores on the Health Sciences Reasoning Test (HSRT) with academic and experiential performance in a doctor of pharmacy (PharmD) curriculum. The HSRT was administered to 329 first-year (P1) PharmD students. Performance on the HSRT and its subscales was compared with academic performance in 29 courses throughout the curriculum and with performance in advanced pharmacy practice experiences (APPEs). Significant positive correlations were found between course grades in 8 courses and HSRT overall scores. All significant correlations were accounted for by pharmaceutical care laboratory courses, therapeutics courses, and a law and ethics course. There was a lack of moderate to strong correlation between HSRT scores and academic and experiential performance. The usefulness of the HSRT as a tool for predicting student success may be limited.

  7. Human reasoning and cognitive science

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    Stenning, K.; van Lambalgen, M.

    2008-01-01

    In Human Reasoning and Cognitive Science, Keith Stenning and Michiel van Lambalgen—a cognitive scientist and a logician—argue for the indispensability of modern mathematical logic to the study of human reasoning. Logic and cognition were once closely connected, they write, but were "divorced" in the

  8. Scientific reasoning during adolescence: The influence of instruction in science knowledge and reasoning strategies

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    Linn, M. C.; Clement, C.; Pulos, S.; Sullivan, P.

    The mechanism linking instruction in scientific topics and instruction in logical reasoning strategies is not well understood. This study assesses the role of science topic instruction combined with logical reasoning strategy instruction in teaching adolescent students about blood pressure problems. Logical reasoning instruction for this study emphasizes the controlling-variables strategy. Science topic instruction emphasizes variables affecting blood pressure. Subjects receiving logical reasoning instruction link their knowledge of blood pressure variables to their knowledge of controlling variables more effectively than those receiving science topic instruction alone - their specific responses show how they attempt to integrate their understanding.Received: 15 April 1988

  9. Turkish Preservice Science Teachers' Informal Reasoning regarding Socioscientific Issues and the Factors Influencing Their Informal Reasoning

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    Topcu, Mustafa Sami; Yilmaz-Tuzun, Ozgul; Sadler, Troy D.

    2011-01-01

    The purpose of the study is to explore Turkish preservice science teachers' informal reasoning regarding socioscientific issues and the factors influencing their informal reasoning. The researchers engaged 39 preservice science teachers in informal reasoning interview and moral decision-making interview protocols. Of the seven socioscientific…

  10. Language-Based Reasoning in Primary Science

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    Hackling, Mark; Sherriff, Barbara

    2015-01-01

    Language is critical in the mediation of scientific reasoning, higher-order thinking and the development of scientific literacy. This study investigated how an exemplary primary science teacher scaffolds and supports students' reasoning during a Year 4 materials unit. Lessons captured on video, teacher and student interviews and micro-ethnographic…

  11. Turkish Preservice Science Teachers' Informal Reasoning Regarding Socioscientific Issues and the Factors Influencing Their Informal Reasoning

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    Topçu, Mustafa Sami; Yılmaz-Tüzün, Özgül; Sadler, Troy D.

    2011-06-01

    The purpose of the study is to explore Turkish preservice science teachers' informal reasoning regarding socioscientific issues and the factors influencing their informal reasoning. The researchers engaged 39 preservice science teachers in informal reasoning interview and moral decision-making interview protocols. Of the seven socioscientific issues, three issues were related to gene therapy, another three were related to human cloning, and one was related to global warming. The data were analyzed using an interpretive qualitative research approach. The characteristic of informal reasoning was determined as multidimensional, and the patterns of informal reasoning emerged as rationalistic, emotive, and intuitive reasoning. The factors influencing informal reasoning were: personal experiences, social considerations, moral-ethical considerations, and technological concerns.

  12. The use of the bi-factor model to test the uni-dimensionality of a battery of reasoning tests.

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    Primi, Ricardo; Rocha da Silva, Marjorie Cristina; Rodrigues, Priscila; Muniz, Monalisa; Almeida, Leandro S

    2013-02-01

    The Battery of Reasoning Tests 5 (BPR-5) aims to assess the reasoning ability of individuals, using sub-tests with different formats and contents that require basic processes of inductive and deductive reasoning for their resolution. The BPR has three sequential forms: BPR-5i (for children from first to fifth grade), BPR-5 - Form A (for children from sixth to eighth grade) and BPR-5 - form B (for high school and undergraduate students). The present study analysed 412 questionnaires concerning BPR-5i, 603 questionnaires concerning BPR-5 - Form A and 1748 questionnaires concerning BPR-5 - Form B. The main goal was to test the uni-dimensionality of the battery and its tests in relation to items using the bi-factor model. Results suggest that the g factor loadings (extracted by the uni-dimensional model) do not change when the data is adjusted for a more flexible multi-factor model (bi-factor model). A general reasoning factor underlying different contents items is supported.

  13. Investigating the Correlation Between Pharmacy Student Performance on the Health Science Reasoning Test and a Critical Thinking Assignment.

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    Nornoo, Adwoa O; Jackson, Jonathan; Axtell, Samantha

    2017-03-25

    Objective. To determine whether there is a correlation between pharmacy students' scores on the Health Science Reasoning Test (HSRT) and their grade on a package insert assignment designed to assess critical thinking. Methods. The HSRT was administered to first-year pharmacy students during a critical-thinking course in the spring semester. In the same semester, a required package insert assignment was completed in a pharmacokinetics course. To determine whether there was a relationship between HSRT scores and grades on the assignment, a Spearman's rho correlation test was performed. Results. A very weak but significant positive correlation was found between students' grades on the assignment and their overall HSRT score (r=0.19, p critical-thinking skills in pharmacy students.

  14. Science Teachers' Analogical Reasoning

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    Mozzer, Nilmara Braga; Justi, Rosária

    2013-08-01

    Analogies can play a relevant role in students' learning. However, for the effective use of analogies, teachers should not only have a well-prepared repertoire of validated analogies, which could serve as bridges between the students' prior knowledge and the scientific knowledge they desire them to understand, but also know how to introduce analogies in their lessons. Both aspects have been discussed in the literature in the last few decades. However, almost nothing is known about how teachers draw their own analogies for instructional purposes or, in other words, about how they reason analogically when planning and conducting teaching. This is the focus of this paper. Six secondary teachers were individually interviewed; the aim was to characterize how they perform each of the analogical reasoning subprocesses, as well as to identify their views on analogies and their use in science teaching. The results were analyzed by considering elements of both theories about analogical reasoning: the structural mapping proposed by Gentner and the analogical mechanism described by Vosniadou. A comprehensive discussion of our results makes it evident that teachers' content knowledge on scientific topics and on analogies as well as their pedagogical content knowledge on the use of analogies influence all their analogical reasoning subprocesses. Our results also point to the need for improving teachers' knowledge about analogies and their ability to perform analogical reasoning.

  15. Development of Reasoning Test Instruments Based on TIMSS Framework for Measuring Reasoning Ability of Senior High School Student on the Physics Concept

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    Muslim; Suhandi, A.; Nugraha, M. G.

    2017-02-01

    The purposes of this study are to determine the quality of reasoning test instruments that follow the framework of Trends in International Mathematics and Science Study (TIMSS) as a development results and to analyse the profile of reasoning skill of senior high school students on physics materials. This research used research and development method (R&D), furthermore the subject were 104 students at three senior high schools in Bandung selected by random sampling technique. Reasoning test instruments are constructed following the TIMSS framework in multiple choice forms in 30 questions that cover five subject matters i.e. parabolic motion and circular motion, Newton’s law of gravity, work and energy, harmonic oscillation, as well as the momentum and impulse. The quality of reasoning tests were analysed using the Content Validity Ratio (CVR) and classic test analysis include the validity of item, level of difficulty, discriminating power, reliability and Ferguson’s delta. As for the students’ reasoning skills profiles were analysed by the average score of achievements on eight aspects of the reasoning TIMSS framework. The results showed that reasoning test have a good quality as instruments to measure reasoning skills of senior high school students on five matters physics which developed and able to explore the reasoning of students on all aspects of reasoning based on TIMSS framework.

  16. Secondary School Students' Understanding of Science and Their Socioscientific Reasoning

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    Karahan, Engin; Roehrig, Gillian

    2017-08-01

    Research in socioscientific issue (SSI)-based interventions is relatively new (Sadler in Journal of Research in Science Teaching 41:513-536, 2004; Zeidler et al. in Journal of Research in Science Teaching 46:74-101, 2009), and there is a need for understanding more about the effects of SSI-based learning environments (Sadler in Journal of Research in Science Teaching 41:513-536, 2004). Lee and Witz (International Journal of Science Education 31:931-960, 2009) highlighted the need for detailed case studies that would focus on how students respond to teachers' practices of teaching SSI. This study presents case studies that investigated the development of secondary school students' science understanding and their socioscientific reasoning within SSI-based learning environments. A multiple case study with embedded units of analysis was implemented for this research because of the contextual differences for each case. The findings of the study revealed that students' understanding of science, including scientific method, social and cultural influences on science, and scientific bias, was strongly influenced by their experiences in SSI-based learning environments. Furthermore, multidimensional SSI-based science classes resulted in students having multiple reasoning modes, such as ethical and economic reasoning, compared to data-driven SSI-based science classes. In addition to portraying how participants presented complexity, perspectives, inquiry, and skepticism as aspects of socioscientific reasoning (Sadler et al. in Research in Science Education 37:371-391, 2007), this study proposes the inclusion of three additional aspects for the socioscientific reasoning theoretical construct: (1) identification of social domains affecting the SSI, (2) using cost and benefit analysis for evaluation of claims, and (3) understanding that SSIs and scientific studies around them are context-bound.

  17. Understanding the Complex Relationship between Critical Thinking and Science Reasoning among Undergraduate Thesis Writers.

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    Dowd, Jason E; Thompson, Robert J; Schiff, Leslie A; Reynolds, Julie A

    2018-01-01

    Developing critical-thinking and scientific reasoning skills are core learning objectives of science education, but little empirical evidence exists regarding the interrelationships between these constructs. Writing effectively fosters students' development of these constructs, and it offers a unique window into studying how they relate. In this study of undergraduate thesis writing in biology at two universities, we examine how scientific reasoning exhibited in writing (assessed using the Biology Thesis Assessment Protocol) relates to general and specific critical-thinking skills (assessed using the California Critical Thinking Skills Test), and we consider implications for instruction. We find that scientific reasoning in writing is strongly related to inference , while other aspects of science reasoning that emerge in writing (epistemological considerations, writing conventions, etc.) are not significantly related to critical-thinking skills. Science reasoning in writing is not merely a proxy for critical thinking. In linking features of students' writing to their critical-thinking skills, this study 1) provides a bridge to prior work suggesting that engagement in science writing enhances critical thinking and 2) serves as a foundational step for subsequently determining whether instruction focused explicitly on developing critical-thinking skills (particularly inference ) can actually improve students' scientific reasoning in their writing. © 2018 J. E. Dowd et al. CBE—Life Sciences Education © 2018 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  18. A comprehensive test of clinical reasoning for medical students: An olympiad experience in Iran.

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    Monajemi, Alireza; Arabshahi, Kamran Soltani; Soltani, Akbar; Arbabi, Farshid; Akbari, Roghieh; Custers, Eugene; Hadadgar, Arash; Hadizadeh, Fatemeh; Changiz, Tahereh; Adibi, Peyman

    2012-01-01

    Although some tests for clinical reasoning assessment are now available, the theories of medical expertise have not played a major role in this filed. In this paper, illness script theory was chose as a theoretical framework and contemporary clinical reasoning tests were put together based on this theoretical model. This paper is a qualitative study performed with an action research approach. This style of research is performed in a context where authorities focus on promoting their organizations' performance and is carried out in the form of teamwork called participatory research. Results are presented in four parts as basic concepts, clinical reasoning assessment, test framework, and scoring. we concluded that no single test could thoroughly assess clinical reasoning competency, and therefore a battery of clinical reasoning tests is needed. This battery should cover all three parts of clinical reasoning process: script activation, selection and verification. In addition, not only both analytical and non-analytical reasoning, but also both diagnostic and management reasoning should evenly take into consideration in this battery. This paper explains the process of designing and implementing the battery of clinical reasoning in the Olympiad for medical sciences students through an action research.

  19. Elementary Children’s Retrodictive Reasoning about Earth Science

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    Julie C. LIBARKIN

    2012-10-01

    Full Text Available We report on interviews conducted with twenty-one elementary school children (grades 1-5 about a number of Earth science concepts. These interviews were undertaken as part of a teacher training video series designed specifically to assist elementary teachers in learning essential ideas in Earth science. As such, children were interviewed about a wide array of earth science concepts, from rock formation to the Earth’s interior. We analyzed interview data primarily to determine whether or not young children are capable of inferring understanding of the past based on present-day observation (retrodictive reasoning in the context of Earth science. This work provides a basis from which curricula for teaching earth and environmental sciences can emerge, and suggests that new studies into the retrodictive reasoning abilities of young children are needed, including curricula that encourage inference of the past from modern observations.

  20. The Analysis of Students Scientific Reasoning Ability in Solving the Modified Lawson Classroom Test of Scientific Reasoning (MLCTSR Problems by Applying the Levels of Inquiry

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    N. Novia

    2017-04-01

    Full Text Available This study aims to determine the students’ achievement in answering modified lawson classroom test of scientific reasoning (MLCTSR questions in overall science teaching and by every aspect of scientific reasoning abilities. There are six aspects related to the scientific reasoning abilities that were measured; they are conservatorial reasoning, proportional reasoning, controlling variables, combinatorial reasoning, probabilistic reasoning, correlational reasoning. The research is also conducted to see the development of scientific reasoning by using levels of inquiry models. The students reasoning ability was measured using the Modified Lawson Classroom Test of Scientific Reasoning (MLCTSR. MLCTSR is a test developed based on the test of scientific reasoning of Lawson’s Classroom Test of Scientific Reasoning (LCTSR in 2000 which amounted to 12 multiple-choice questions. The research method chosen in this study is descriptive quantitative research methods. The research design used is One Group Pretest-Posttest Design. The population of this study is the entire junior high students class VII the academic year 2014/2015 in one junior high school in Bandung. The samples in this study are one of class VII, which is class VII C. The sampling method used in this research is purposive sampling. The results showed that there is an increase in quantitative scientific reasoning although its value is not big.

  1. Examination of the relationship between preservice science teachers' scientific reasoning and problem solving skills on basic mechanics

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    Yuksel, Ibrahim; Ates, Salih

    2018-02-01

    The purpose of this study is to determine relationship between scientific reasoning and mechanics problem solving skills of students in science education program. Scientific Reasoning Skills Test (SRST) and Basic Mechanics Knowledge Test (BMKT) were applied to 90 second, third and fourth grade students who took Scientific Reasoning Skills course at science teaching program of Gazi Faculty of Education for three successive fall semesters of 2014, 2015 and 2016 academic years. It was found a statistically significant positive (p = 0.038 <0.05) but a low correlation (r = 0.219) between SRST and BMKT. There were no significant relationship among Conservation Laws, Proportional Thinking, Combinational Thinking, Correlational Thinking, Probabilistic Thinking subskills of reasoning and BMKT. There were significant and positive correlation among Hypothetical Thinking and Identifying and Controlling Variables subskills of reasoning and BMKT. The findings of the study were compared with other studies in the field and discussed.

  2. Engaging students in learning science through promoting creative reasoning

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    Waldrip, Bruce; Prain, Vaughan

    2017-10-01

    Student engagement in learning science is both a desirable goal and a long-standing teacher challenge. Moving beyond engagement understood as transient topic interest, we argue that cognitive engagement entails sustained interaction in the processes of how knowledge claims are generated, judged, and shared in this subject. In this paper, we particularly focus on the initial claim-building aspect of this reasoning as a crucial phase in student engagement. In reviewing the literature on student reasoning and argumentation, we note that the well-established frameworks for claim-judging are not matched by accounts of creative reasoning in claim-building. We develop an exploratory framework to characterise and enact this reasoning to enhance engagement. We then apply this framework to interpret two lessons by two science teachers where they aimed to develop students' reasoning capabilities to support learning.

  3. Quantitative Reasoning in Environmental Science: A Learning Progression

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    Mayes, Robert Lee; Forrester, Jennifer Harris; Christus, Jennifer Schuttlefield; Peterson, Franziska Isabel; Bonilla, Rachel; Yestness, Nissa

    2014-01-01

    The ability of middle and high school students to reason quantitatively within the context of environmental science was investigated. A quantitative reasoning (QR) learning progression was created with three progress variables: quantification act, quantitative interpretation, and quantitative modeling. An iterative research design was used as it…

  4. Quantitative Reasoning Learning Progressions for Environmental Science: Developing a Framework

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    Robert L. Mayes

    2013-01-01

    Full Text Available Quantitative reasoning is a complex concept with many definitions and a diverse account in the literature. The purpose of this article is to establish a working definition of quantitative reasoning within the context of science, construct a quantitative reasoning framework, and summarize research on key components in that framework. Context underlies all quantitative reasoning; for this review, environmental science serves as the context.In the framework, we identify four components of quantitative reasoning: the quantification act, quantitative literacy, quantitative interpretation of a model, and quantitative modeling. Within each of these components, the framework provides elements that comprise the four components. The quantification act includes the elements of variable identification, communication, context, and variation. Quantitative literacy includes the elements of numeracy, measurement, proportional reasoning, and basic probability/statistics. Quantitative interpretation includes the elements of representations, science diagrams, statistics and probability, and logarithmic scales. Quantitative modeling includes the elements of logic, problem solving, modeling, and inference. A brief comparison of the quantitative reasoning framework with the AAC&U Quantitative Literacy VALUE rubric is presented, demonstrating a mapping of the components and illustrating differences in structure. The framework serves as a precursor for a quantitative reasoning learning progression which is currently under development.

  5. Comparing Two Tests of Formal Reasoning in a College Chemistry Context

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    Jiang, Bo; Xu, Xiaoying; Garcia, Alicia; Lewis, Jennifer E.

    2010-01-01

    The Test of Logical Thinking (TOLT) and the Group Assessment of Logical Thinking (GALT) are two of the instruments most widely used by science educators and researchers to measure students' formal reasoning abilities. Based on Piaget's cognitive development theory, formal thinking ability has been shown to be essential for student achievement in…

  6. Developing a Construct-Based Assessment to Examine Students' Analogical Reasoning around Physical Models in Earth Science

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    Rivet, Ann E.; Kastens, Kim A.

    2012-01-01

    In recent years, science education has placed increasing importance on learners' mastery of scientific reasoning. This growing emphasis presents a challenge for both developers and users of assessments. We report on our effort around the conceptualization, development, and testing the validity of an assessment of students' ability to reason around…

  7. A study of the effects of English language proficiency and scientific reasoning skills on the acquisition of science content knowledge of Hispanic English language learners and native English language-speaking students participating in grade 10 science classes

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    Torres, Hector Neftali, Sr.

    2000-11-01

    The purpose of this study was to examine the effects of English language proficiency and levels of scientific reasoning skills of Hispanic English language learners and native English language speaking students on their acquisition of science content knowledge as measured by a state-wide standardized science test. The researcher studied a group of high school Hispanic English language learners and native English language speaking students participating in Grade 10 science classes. The language proficiency of the students was to be measured through the use of the Test of English as a Foreign Language (TOEFL) instrument. A Classroom Test of Scientific Reasoning developed by Lawson (1978) was administered in either English or Spanish to the group of Hispanic English language learners and in English to the group of native English language-speaking students in order to determine their levels of scientific reasoning skills. The students' acquisition of science content knowledge was measured through the use of statewide-standardized science test developed by the State's Department of Education. This study suggests that the levels of English language proficiency appear to influence the acquisition of science content knowledge of Hispanic English language learners in the study. The results of the study also suggest that with regards to scientific reasoning skills, students that showed high levels or reflective reasoning skills for the most part performed better on the statewide-standardized science test than students with intuitive or transitional reasoning skills. This assertion was supported by the studies conducted by Lawson and his colleagues, which showed that high levels of reasoning or reflective reasoning skills are prerequisite for most high school science courses. The findings in this study imply that high order English language proficiency combined with high levels of reasoning skills enhances students' abilities to learn science content subject matter. This

  8. What makes a good experiment ? reasons and roles in science

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    Franklin, Allan

    2016-01-01

    What makes a good experiment? Although experimental evidence plays an essential role in science, as Franklin argues, there is no algorithm or simple set of criteria for ranking or evaluating good experiments, and therefore no definitive answer to the question. Experiments can, in fact, be good in any number of ways: conceptually good, methodologically good, technically good, and pedagogically important. And perfection is not a requirement: even experiments with incorrect results can be good, though they must, he argues, be methodologically good, providing good reasons for belief in their results. Franklin revisits the same important question he posed in his 1981 article in the British Journal for the Philosophy of Science, when it was generally believed that the only significant role of experiment in science was to test theories. But experiments can actually play a lot of different roles in science—they can, for example, investigate a subject for which a theory does not exist, help to articulate an existing ...

  9. Toward an Analytic Framework of Interdisciplinary Reasoning and Communication (IRC) Processes in Science

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    Shen, Ji; Sung, Shannon; Zhang, Dongmei

    2015-11-01

    Students need to think and work across disciplinary boundaries in the twenty-first century. However, it is unclear what interdisciplinary thinking means and how to analyze interdisciplinary interactions in teamwork. In this paper, drawing on multiple theoretical perspectives and empirical analysis of discourse contents, we formulate a theoretical framework that helps analyze interdisciplinary reasoning and communication (IRC) processes in interdisciplinary collaboration. Specifically, we propose four interrelated IRC processes-integration, translation, transfer, and transformation, and develop a corresponding analytic framework. We apply the framework to analyze two meetings of a project that aims to develop interdisciplinary science assessment items. The results illustrate that the framework can help interpret the interdisciplinary meeting dynamics and patterns. Our coding process and results also suggest that these IRC processes can be further examined in terms of interconnected sub-processes. We also discuss the implications of using the framework in conceptualizing, practicing, and researching interdisciplinary learning and teaching in science education.

  10. Preservice Science Teachers' Epistemological Beliefs and Informal Reasoning Regarding Socioscientific Issues

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    Ozturk, Nilay; Yilmaz-Tuzun, Ozgul

    2017-12-01

    This study investigated preservice elementary science teachers' (PSTs) informal reasoning regarding socioscientific issues (SSI), their epistemological beliefs, and the relationship between informal reasoning and epistemological beliefs. From several SSIs, nuclear power usage was selected for this study. A total of 647 Turkish PSTs enrolled in three large universities in Turkey completed the open-ended questionnaire, which assessed the participants' informal reasoning about the target SSI, and Schommer's (1990) Epistemological Questionnaire. The participants' epistemological beliefs were assessed quantitatively and their informal reasoning was assessed both qualitatively and quantitatively. The findings revealed that PSTs preferred to generate evidence-based arguments rather than intuitive-based arguments; however, they failed to generate quality evidence and present different types of evidence to support their claims. Furthermore, among the reasoning quality indicators, PSTs mostly generated supportive argument construction. Regarding the use of reasoning modes, types of risk arguments and political-oriented arguments emerged as the new reasoning modes. The study demonstrated that the PSTs had different epistemological beliefs in terms of innate ability, omniscient authority, certain knowledge, and quick learning. Correlational analyses revealed that there was a strong negative correlation between the PSTs' certain knowledge and counterargument construction, and there were negative correlations between the PSTs' innate ability, certain knowledge, and quick learning dimensions of epistemological beliefs and their total argument construction. This study has implications for both science teacher education and the practice of science education. For example, PST teacher education programs should give sufficient importance to training teachers that are skillful and knowledgeable regarding SSIs. To achieve this, specific SSI-related courses should form part of science

  11. Numerical Analysis of S-CO{sub 2} Test Loop Transient Conditions near the Critical Point of CO{sub 2}

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    Bae, Seong Jun; Oh, Bongseong; Ahn, Yoonhan; Baik, Seongjoon; Lee, Jekyoung; Lee, Jeong Ik [KAIST, Daejeon (Korea, Republic of)

    2016-05-15

    It was identified that controlling CO{sub 2} compressor operation near the critical point is one of the most important issues to operate a S-CO{sub 2} Brayton cycle with a high efficiency. Despite the growing interest in the S-CO{sub 2} Brayton cycle, a few previous research on the transient analysis of the S-CO{sub 2} system has been conducted previously. Moreover, previous studies have some limitation in the modelled test facility, and the experiment was not performed to observe specific scenario. The KAIST research team has conducted S-CO{sub 2} system transient experiments with the CO{sub 2} compressing test facility called SCO{sub 2}PE (Supercritical CO{sub 2} Pressurizing Experiment) at KAIST In this study, authors use the transient analysis code GAMMA (Gas Multidimensional Multicomponent mixture Analysis) code for analyzing the experiment. Two transient scenarios were selected in this study; over cooling and under cooling situations. The selected transient situation is of particular interest since the compressor inlet conditions start to drift away from the critical point of CO{sub 2}. The results represent that the GAMMA code can simulate the S-CO{sub 2} test facility, SCO{sub 2}PE. However, as shown in the cooling water flow rate increasing scenario, the GAMMA code shows calculation error when the phase change occurs. Furthermore, although the results of the cooling water flow rate decrease case shows reasonable agreement with the experimental data, there are still some unexplained differences between the experimental data and the GAMMA code prediction.

  12. Assessment of Scientific Reasoning: the Effects of Task Context, Data, and Design on Student Reasoning in Control of Variables.

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    Zhou, Shaona; Han, Jing; Koenig, Kathleen; Raplinger, Amy; Pi, Yuan; Li, Dan; Xiao, Hua; Fu, Zhao; Bao, Lei

    2016-03-01

    Scientific reasoning is an important component under the cognitive strand of the 21st century skills and is highly emphasized in the new science education standards. This study focuses on the assessment of student reasoning in control of variables (COV), which is a core sub-skill of scientific reasoning. The main research question is to investigate the extent to which the existence of experimental data in questions impacts student reasoning and performance. This study also explores the effects of task contexts on student reasoning as well as students' abilities to distinguish between testability and causal influences of variables in COV experiments. Data were collected with students from both USA and China. Students received randomly one of two test versions, one with experimental data and one without. The results show that students from both populations (1) perform better when experimental data are not provided, (2) perform better in physics contexts than in real-life contexts, and (3) students have a tendency to equate non-influential variables to non-testable variables. In addition, based on the analysis of both quantitative and qualitative data, a possible progression of developmental levels of student reasoning in control of variables is proposed, which can be used to inform future development of assessment and instruction.

  13. Understanding and Affecting Science Teacher Candidates' Scientific Reasoning in Introductory Astrophysics

    Science.gov (United States)

    Steinberg, Richard; Cormier, Sebastien

    2013-01-01

    This study reports on a content course for science immersion teacher candidates that emphasized authentic practice of science and thinking scientifically in the context of introductory astrophysics. We explore how 122 science teacher candidates spanning three cohorts did and did not reason scientifically and how this evolved in our program. Our…

  14. Acceptance of HIV testing among women attending antenatal care in south-western Uganda: risk factors and reasons for test refusal.

    Science.gov (United States)

    Dahl, V; Mellhammar, L; Bajunirwe, F; Björkman, P

    2008-07-01

    A problem commonly encountered in programs for prevention of mother-to-child-transmission (PMTCT) of HIV in sub-Saharan Africa is low rates of HIV test acceptance among pregnant women. In this study, we examined risk factors and reasons for HIV test refusal among 432 women attending three antenatal care clinics offering PMTCT in urban and semi-urban parts of the Mbarara district, Uganda. Structured interviews were performed following pre-test counselling. Three-hundred-eighty women were included in the study, 323 (85%) of whom accepted HIV testing. In multivariate analysis, testing site (Site A: OR = 1.0; Site B: OR = 3.08; 95%CI: 1.12-8.46; Site C: OR = 5.93; 95%CI: 2.94-11.98), age between 30 and 34 years (refusal. Testing sites operating for longer durations had higher rates of acceptance. The most common reasons claimed for test refusal were: lack of access to antiretroviral therapy (ART) for HIV-infected women (88%; n=57), a need to discuss with partner before decision (82%; n=57) and fear of partner's reaction (54%; n=57). Comparison with previous periods showed that the acceptance rate increased with the duration of the program. Our study identified risk factors for HIV test refusal among pregnant women in Uganda and common reasons for not accepting testing. These findings may suggest modifications and improvements in the performance of HIV testing in this and similar populations.

  15. A Chemistry Concept Reasoning Test

    Science.gov (United States)

    Cloonan, Carrie A.; Hutchinson, John S.

    2011-01-01

    A Chemistry Concept Reasoning Test was created and validated providing an easy-to-use tool for measuring conceptual understanding and critical scientific thinking of general chemistry models and theories. The test is designed to measure concept understanding comparable to that found in free-response questions requiring explanations over…

  16. Science Granting Councils Initiative in Sub-Saharan Africa ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    This initiative seeks to strengthen the capacities of science granting councils in East Africa and other selected sub-Saharan African countries. The goal is to contribute to economic and social development in the region through research and evidence-based policies. About the science granting councils initiative The Science ...

  17. The Effect of Problem-Solving Video Games on the Science Reasoning Skills of College Students

    Science.gov (United States)

    Fanetti, Tina M.

    As the world continues to rapidly change, students are faced with the need to develop flexible skills, such as science reasoning that will help them thrive in the new knowledge economy. Prensky (2001), Gee (2003), and Van Eck (2007) have all suggested that the way to engage learners and teach them the necessary skills is through digital games, but empirical studies focusing on popular games are scant. One way digital games, especially video games, could potentially be useful if there were a flexible and inexpensive method a student could use at their convenience to improve selected science reasoning skills. Problem-solving video games, which require the use of reasoning and problem solving to answer a variety of cognitive challenges could be a promising method to improve selected science reasoning skills. Using think-aloud protocols and interviews, a qualitative study was carried out with a small sample of college students to examine what impact two popular video games, Professor Layton and the Curious Village and Professor Layton and the Diabolical Box, had on specific science reasoning skills. The subject classified as an expert in both gaming and reasoning tended to use more higher order thinking and reasoning skills than the novice reasoners. Based on the assessments, the science reasoning of college students did not improve during the course of game play. Similar to earlier studies, students tended to use trial and error as their primary method of solving the various puzzles in the game and additionally did not recognize when to use the appropriate reasoning skill to solve a puzzle, such as proportional reasoning.

  18. Reasonable assurance and in-situ testing

    International Nuclear Information System (INIS)

    Rhoderick, J.E.; Nelson, J.W.

    1986-01-01

    The Department of Energy is currently preparing site characterization plans for sites being considered for the first geologic repository. The site investigations described in these plans will be aimed at providing ''reasonable assurance'' to the Nuclear Regulatory Commission that the performance objectives and criteria specified in 10 CFR Part 60 will be met. The in-situ testing being planned by the DOE for site characterization, and the subsequent testing conducted as part of performance confirmation, reflects how the basis for ''reasonable assurance'' will change through the licensing process

  19. Gender, mathematics, reading comprehension and science reasoning as predictors of science achievement among African-American students at a historical black college or university

    Science.gov (United States)

    Davis, Consuella Artiemese

    This study investigated predictors that influence the science achievement of African-American non-science majors in a Physical Science class. The population consisted of male and female college students enrolled in Physical Science courses at a historical black college or university (HBCU) located in the southeastern portion of the United States. A personal data information sheet was administered to 120 participants during the Fall of 2008. The personal data information sheet consisted of questions pertaining to the high school courses, students took in math, language arts and science. It also consisted of basic background information. Students also gave written consent for their midterm and final grades earned in Physical Science to be used in the study as part of the analyses. A t-Test including chi-square tests revealed that there was not a significant difference in the raw scores of African-American females and African American males on the American College Test. A significant difference was not observed between the females and males on the ACT math subtest, t (118) = -.78, p = .43; reading comprehension subtest, t (118) = -1.44, .15 or on the science reasoning subtest, t (118) = -1.46, p = .15. A significant difference was not found between the final grades of African American females and the final grades of African American males. Chi-square tests were conducted to determine goodness of fit, X2 = 6.11, df = 1, p = .191. Although the grades of females were higher than males, results were not significant. The correlation between math ACT and final grades were not significant, r = .131, N = 120, p = .155, reading comprehension ACT and final grades were not significant, r = .072, N = 120, p = .434 and science reasoning ACT and final grades were found not to be significant, r = .109, N = 120, p = .237. Being that the majority of students who participated in the study were from one state, had similar high school backgrounds, had similar majors and were similar in

  20. Population Health Science: A Core Element of Health Science Education in Sub-Saharan Africa.

    Science.gov (United States)

    Hiatt, Robert A; Engmann, Natalie J; Ahmed, Mushtaq; Amarsi, Yasmin; Macharia, William M; Macfarlane, Sarah B; Ngugi, Anthony K; Rabbani, Fauziah; Walraven, Gijs; Armstrong, Robert W

    2017-04-01

    Sub-Saharan Africa suffers an inordinate burden of disease and does not have the numbers of suitably trained health care workers to address this challenge. New concepts in health sciences education are needed to offer alternatives to current training approaches.A perspective of integrated training in population health for undergraduate medical and nursing education is advanced, rather than continuing to take separate approaches for clinical and public health education. Population health science educates students in the social and environmental origins of disease, thus complementing disease-specific training and providing opportunities for learners to take the perspective of the community as a critical part of their education.Many of the recent initiatives in health science education in sub-Saharan Africa are reviewed, and two case studies of innovative change in undergraduate medical education are presented that begin to incorporate such population health thinking. The focus is on East Africa, one of the most rapidly growing economies in sub-Saharan Africa where opportunities for change in health science education are opening. The authors conclude that a focus on population health is a timely and effective way for enhancing training of health care professionals to reduce the burden of disease in sub-Saharan Africa.

  1. Reasons Why Some Women Quit Science

    Science.gov (United States)

    Tabazadeh, A.

    2002-12-01

    Nearly half of all graduate students majoring in various disciplines of science today are women, yet men still predominate the faculty makeup at most universities and research institutions. This issue was discussed at length last year in the journal Science and also in the Chemical Engineering News (the ACS weekly publication magazine). The question is: why do so many women decide to major in science but not to pursue a career in science? Over the years I have seen highly capable women quit science for two main reasons. First, intimidation that can be very difficult to deal with when someone is just starting a career in science. Thus, I encourage young women to make a sincere effort to surround themselves with colleagues who are both knowledgeable and considerate. Keep in my mind that you have a choice to choose your future collaborators, so make some smart choices early on and throughout your career. Second, is the need to balance the demands of work with those of family life. Personally, I don't believe a tenure system is fair to young women who wish to have children during this appointment. The level of stress can be very high, which prevents women from applying to a position where they are given only a few short years to prove themselves. Also, try not to make a radical decision (i.e. quit science) if you are too stressed. Talk to more senior women in the field to learn how to better deal with your stress. After all a career in science has many ups and downs, and to survive, one needs to balance the good and bad days. In this talk I will address the questions outlined in the announcement as they relate to me. Overall, my advice to young women who are just starting their scientific careers is to celebrate your accomplishments and learn from your mistakes.

  2. Science Granting Councils Initiative in Sub-Saharan Africa | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... the increasingly important role of these councils in national science systems. ... that will contribute to economic and social development in Sub-Saharan Africa. ... Initiative for Sub-Saharan Africa's website to learn more about the initiative.

  3. Mathematical Reasoning Requirements in Swedish National Physics Tests

    Science.gov (United States)

    Johansson, Helena

    2016-01-01

    This paper focuses on one aspect of mathematical competence, namely mathematical reasoning, and how this competency influences students' knowing of physics. This influence was studied by analysing the mathematical reasoning requirements upper secondary students meet when solving tasks in national physics tests. National tests are constructed to…

  4. Logical studies of paraconsistent reasoning in science and mathematics

    CERN Document Server

    Verdée, Peter

    2016-01-01

    This book covers work written by leading scholars from different schools within the research area of paraconsistency. The authors critically investigate how contemporary paraconsistent logics can be used to better understand human reasoning in science and mathematics. Offering a variety of perspectives, they shed a new light on the question of whether paraconsistent logics can function as the underlying logics of inconsistent but useful scientific and mathematical theories. The great variety of paraconsistent logics gives rise to various, interrelated questions, such as what are the desiderata a paraconsistent logic should satisfy, is there prospect of a universal approach to paraconsistent reasoning with axiomatic theories, and to what extent is reasoning about sets structurally analogous to reasoning about truth. Furthermore, the authors consider paraconsistent logic’s status as either a normative or descriptive discipline (or one which falls in between) and which inconsistent but non-trivial axiomatic th...

  5. How and when Does Complex Reasoning Occur? Empirically Driven Development of a Learning Progression Focused on Complex Reasoning about Biodiversity

    Science.gov (United States)

    Songer, Nancy Butler; Kelcey, Ben; Gotwals, Amelia Wenk

    2009-01-01

    In order to compete in a global economy, students are going to need resources and curricula focusing on critical thinking and reasoning in science. Despite awareness for the need for complex reasoning, American students perform poorly relative to peers on international standardized tests measuring complex thinking in science. Research focusing on…

  6. Science Thought and Practices: A Professional Development Workshop on Teaching Scientific Reasoning, Mathematical Modeling and Data Analysis

    Science.gov (United States)

    Robbins, Dennis; Ford, K. E. Saavik

    2018-01-01

    The NSF-supported “AstroCom NYC” program, a collaboration of the City University of New York and the American Museum of Natural History (AMNH), has developed and offers hands-on workshops to undergraduate faculty on teaching science thought and practices. These professional development workshops emphasize a curriculum and pedagogical strategies that uses computers and other digital devices in a laboratory environment to teach students fundamental topics, including: proportional reasoning, control of variables thinking, experimental design, hypothesis testing, reasoning with data, and drawing conclusions from graphical displays. Topics addressed here are rarely taught in-depth during the formal undergraduate years and are frequently learned only after several apprenticeship research experiences. The goal of these workshops is to provide working and future faculty with an interactive experience in science learning and teaching using modern technological tools.

  7. Measurement Model of Reasoning Skills among Science Students Based on Socio Scientific Issues (SSI

    Directory of Open Access Journals (Sweden)

    MOHD AFIFI BAHURUDIN SETAMBAH

    2018-05-01

    Full Text Available The lack of reasoning skills has been recognized as one of the contributing factors to the declined achievement in the Trends in Mathematics and Science Studies (TIMSS and Programme for International Student Assessment (PISA assessments in Malaysia. The use of socio-scientific issues (SSI as a learning strategy offers the potential of improving the level of students' reasoning skills and consequently improves students’ achievement in science subjects. This study examined the development of a measurement model of reasoning skills among science students based on SSI using the analysis of moment structure (AMOS approach before going to second level to full structured equation modelling (SEM. A total of 450 respondents were selected using a stratified random sampling. Results showed a modified measurement model of reasoning skills consisting of the View Knowledge (VK was as a main construct. The items that measure the level of pre-reflection of students fulfilled the elements of unidimensionality, validity, and reliability. Although the level of student reasoning skills was still low but this development of measurement model could be identified and proposed teaching methods that could be adopted to improve students’ reasoning skills.

  8. Intuition & reason: re-assessing dual-process theories with representational sub-activation

    OpenAIRE

    Trafford, James; Tillas, Alexandros

    2015-01-01

    There is a prevalent distinction in the literature on reasoning, between Type-1 processes, (fast, automatic, associative, heuristic and intuitive); and Type-2 processes (rule-based, analytical and reflective). In this paper, we follow up recent empirical evidence [De Neys (2006b); Osman (2013)] in favour of a unitary cognitive system. More specifically, we suggest that intuitions (T1-processes) are sub-activated representations, which are in turn influenced by the weightings of the connection...

  9. High school science teacher perceptions of the science proficiency testing as mandated by the State of Ohio Board of Education

    Science.gov (United States)

    Jeffery, Samuel Shird

    There is a correlation between the socioeconomic status of secondary schools and scores on the State of Ohio's mandated secondary science proficiency tests. In low scoring schools many reasons effectively explain the low test scores as a result of the low socioeconomics. For example, one reason may be that many students are working late hours after school to help with family finances; parents may simply be too busy providing family income to realize the consequences of the testing program. There are many other personal issues students face that may cause them to score poorly an the test. The perceptions of their teachers regarding the science proficiency test program may be one significant factor. These teacher perceptions are the topic of this study. Two sample groups ware established for this study. One group was science teachers from secondary schools scoring 85% or higher on the 12th grade proficiency test in the academic year 1998--1999. The other group consisted of science teachers from secondary schools scoring 35% or less in the same academic year. Each group of teachers responded to a survey instrument that listed several items used to determine teachers' perceptions of the secondary science proficiency test. A significant difference in the teacher' perceptions existed between the two groups. Some of the ranked items on the form include teachers' opinions of: (1) Teaching to the tests; (2) School administrators' priority placed on improving average test scores; (3) Teacher incentive for improving average test scores; (4) Teacher teaching style change as a result of the testing mandate; (5) Teacher knowledge of State curriculum model; (6) Student stress as a result of the high-stakes test; (7) Test cultural bias; (8) The tests in general.

  10. Analogy-Enhanced Instruction: Effects on Reasoning Skills in Science

    Science.gov (United States)

    Remigio, Krisette B.; Yangco, Rosanelia T.; Espinosa, Allen A.

    2014-01-01

    The study examined the reasoning skills of first year high school students after learning general science concepts through analogies. Two intact heterogeneous sections were randomly assigned to Analogy-Enhanced Instruction (AEI) group and Non Analogy-Enhanced (NAEI) group. Various analogies were incorporated in the lessons of the AEI group for…

  11. The effects of an integrated Algebra 1/physical science curriculum on student achievement in Algebra 1, proportional reasoning and graphing abilities

    Science.gov (United States)

    Lawrence, Lettie Carol

    1997-08-01

    The purpose of this investigation was to determine if an integrated curriculum in algebra 1/physical science facilitates acquisition of proportional reasoning and graphing abilities better than a non-integrated, traditional, algebra 1 curriculum. Also, this study was to ascertain if the integrated algebra 1/physical science curriculum resulted in greater student achievement in algebra 1. The curriculum used in the experimental class was SAM 9 (Science and Mathematics 9), an investigation-based curriculum that was written to integrate physical science and basic algebra content. The experiment was conducted over one school year. The subjects in the study were 61 ninth grade students. The experimental group consisted of one class taught concurrently by a mathematics teacher and a physical science teacher. The control group consisted of three classes of algebra 1 students taught by one mathematics teacher and taking physical science with other teachers in the school who were not participating in the SAM 9 program. This study utilized a quasi-experimental non-randomized control group pretest-posttest design. The investigator obtained end-of-algebra 1 scores from student records. The written open-ended graphing instruments and the proportional reasoning instrument were administered to both groups as pretests and posttests. The graphing instruments were also administered as a midtest. A two sample t-test for independent means was used to determine significant differences in achievement on the end-of-course algebra 1 test. Quantitative data from the proportional reasoning and graphing instruments were analyzed using a repeated measures analysis of variance to determine differences in scores over time for the experimental and control groups. The findings indicate no significant difference between the experimental and control groups on the end-of-course algebra 1 test. Results also indicate no significant differences in proportional reasoning and graphing abilities between

  12. Using a multi-user virtual simulation to promote science content: Mastery, scientific reasoning, and academic self-efficacy in fifth grade science

    Science.gov (United States)

    Ronelus, Wednaud J.

    The purpose of this study was to examine the impact of using a role-playing game versus a more traditional text-based instructional method on a cohort of general education fifth grade students' science content mastery, scientific reasoning abilities, and academic self-efficacy. This is an action research study that employs an embedded mixed methods design model, involving both quantitative and qualitative data. The study is guided by the critical design ethnography theoretical lens: an ethnographic process involving participatory design work aimed at transforming a local context while producing an instructional design that can be used in multiple contexts. The impact of an immersive 3D multi-user web-based educational simulation game on a cohort of fifth-grade students was examined on multiple levels of assessments--immediate, close, proximal and distal. A survey instrument was used to assess students' self-efficacy in technology and scientific inquiry. Science content mastery was assessed at the immediate (participation in game play), close (engagement in-game reports) and proximal (understanding of targeted concepts) levels; scientific reasoning was assessed at the distal (domain general critical thinking test) level. This quasi-experimental study used a convenient sampling method. Seven regular fifth-grade classes participated in this study. Three of the classes were the control group and the other four were the intervention group. A cohort of 165 students participated in this study. The treatment group contained 38 boys and 52 girls, and the control group contained 36 boys and 39 girls. Two-tailed t-test, Analysis of Covariance (ANCOVA), and Pearson Correlation were used to analyze data. The data supported the rejection of the null hypothesis for the three research questions. The correlational analyses showed strong relationship among three of the four variables. There were no correlations between gender and the three dependent variables. The findings of this

  13. The Science Granting Councils Initiative in sub-Saharan Africa wins ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2017-12-18

    Dec 18, 2017 ... Science Diplomacy Awards recognize outstanding achievements in South Africa's ... SGCI was recognized for its work with 15 public funding agencies in sub-Saharan Africa, as well as several science and ... Knowledge.

  14. Reliability of a science admission test (HAM-Nat) at Hamburg medical school.

    Science.gov (United States)

    Hissbach, Johanna; Klusmann, Dietrich; Hampe, Wolfgang

    2011-01-01

    The University Hospital in Hamburg (UKE) started to develop a test of knowledge in natural sciences for admission to medical school in 2005 (Hamburger Auswahlverfahren für Medizinische Studiengänge, Naturwissenschaftsteil, HAM-Nat). This study is a step towards establishing the HAM-Nat. We are investigating parallel forms reliability, the effect of a crash course in chemistry on test results, and correlations of HAM-Nat test results with a test of scientific reasoning (similar to a subtest of the "Test for Medical Studies", TMS). 316 first-year students participated in the study in 2007. They completed different versions of the HAM-Nat test which consisted of items that had already been used (HN2006) and new items (HN2007). Four weeks later half of the participants were tested on the HN2007 version of the HAM-Nat again, while the other half completed the test of scientific reasoning. Within this four week interval students were offered a five day chemistry course. Parallel forms reliability for four different test versions ranged from r(tt)=.53 to r(tt)=.67. The retest reliabilities of the HN2007 halves were r(tt)=.54 and r(tt )=.61. Correlations of the two HAM-Nat versions with the test of scientific reasoning were r=.34 und r=.21. The crash course in chemistry had no effect on HAM-Nat scores. The results suggest that further versions of the test of natural sciences will not easily conform to the standards of internal consistency, parallel-forms reliability and retest reliability. Much care has to be taken in order to assemble items which could be used interchangeably for the construction of new test versions. The test of scientific reasoning and the HAM-Nat are tapping different constructs. Participation in a chemistry course did not improve students' achievement, probably because the content of the course was not coordinated with the test and many students lacked of motivation to do well in the second test.

  15. High School Students' Reasons for Their Science Dispositions: Community-Based Innovative Technology-Embedded Environmental Research Projects

    Science.gov (United States)

    Ebenezer, Jazlin; Kaya, Osman Nafiz; Kasab, Dimma

    2018-05-01

    The purpose of this investigation was to qualitatively describe high school students' reasons for their science dispositions (attitude, perception, and self-confidence) based on their long-term experience with innovative technology-embedded environmental research projects. Students in small groups conducted research projects in and out of school with the help of their teachers and community experts (scientists and engineers). During the 3-year period of this nationally funded project, a total of 135 students from five schools in a mid-west State participated in research activities. Of the 135 students, 53 students were individually interviewed to explore reasons for their science dispositions. Students' reasons for each disposition were grouped into categories, and corresponding frequency was converted to a percentage. The categories of reasons were not only attributed to the use of innovative technologies in environmental research but also the contexts and events that surrounded it. The reasons that influenced students' science dispositions positively were because engaging in environmental research projects with technology contributed to easing fear and difficulty, building a research team, disseminating findings, communicating with the community, researching with scientists, training by teachers, and acknowledging teachers' knowledge. These results advanced how and why students develop science dispositions in the positive direction, which are as follows: building science teacher capacity, developing a community of inquirers, and committing to improve pedagogical practices.

  16. ANALYZE THE KNOWLEDGE INQUIRY SCIENCE PHYSICS TEACHER CANDIDATES WITH ESSENCE INQUIRY SCIENCE TEST INSTRUMENT OPTIKA GEOMETRY

    Directory of Open Access Journals (Sweden)

    Wawan Bunawan

    2013-06-01

    Full Text Available The objective in this research to explore the relationship between ability of the knowledge essential features inquiry science and their reasons underlying sense of scientific inquiry for physics teacher candidates on content geometrical optics. The essential features of inquiry science are components that should arise during the learning process subject matter of geometrical optics reflectance of light on a flat mirror, the reflection of light on curved mirrors and refraction of light at the lens. Five of essential features inquiry science adopted from assessment system developed by the National Research Council. Content geometrical optics developed from an analysis of a college syllabus material. Based on the study of the essential features of inquiry and content develop the multiple choice diagnostic test three tier. Data were taken from the students who are taking courses in optics and wave from one the LPTK in North Sumatra totaled 38 students. Instruments showed Cronbach alpha reliability of 0.67 to test the essential features of inquiry science and 0.61 to there as on geometrical optics science inquiry.

  17. The restructuring of analogical reasoning in planetary science

    Science.gov (United States)

    Soare, Richard J.

    Despite its ubiquity in planetary science, analogue-based reasoning largely has geomorphology and posit rules of use that facilitate the evaluation of Q y, I present four hypotheses concerning aeolian, fluvial and periglacial processes on Mars. Each of these hypotheses is evaluated in terms of the analogical rules presented. The fourth hypothesis is original to this thesis and suggests that a periglacial landscape comprising pingos and small-scale polygonal ground exists in an impact crater located in northwest Utopia Planitia.

  18. A modified PMMA cement (Sub-cement) for accelerated fatigue testing of cemented implant constructs using cadaveric bone.

    Science.gov (United States)

    Race, Amos; Miller, Mark A; Mann, Kenneth A

    2008-10-20

    Pre-clinical screening of cemented implant systems could be improved by modeling the longer-term response of the implant/cement/bone construct to cyclic loading. We formulated bone cement with degraded fatigue fracture properties (Sub-cement) such that long-term fatigue could be simulated in short-term cadaver tests. Sub-cement was made by adding a chain-transfer agent to standard polymethylmethacrylate (PMMA) cement. This reduced the molecular weight of the inter-bead matrix without changing reaction-rate or handling characteristics. Static mechanical properties were approximately equivalent to normal cement. Over a physiologically reasonable range of stress-intensity factor, fatigue crack propagation rates for Sub-cement were higher by a factor of 25+/-19. When tested in a simplified 2 1/2-D physical model of a stem-cement-bone system, crack growth from the stem was accelerated by a factor of 100. Sub-cement accelerated both crack initiation and growth rate. Sub-cement is now being evaluated in full stem/cement/femur models.

  19. An Examination of the Influence of Globalisation on Science Education in Anglophone Sub-Saharan Africa

    Science.gov (United States)

    Koosimile, Anthony T.; Suping, Shanah M.

    2015-09-01

    This paper takes the view that the emergence of some trends and practices in science education mirrors the influence of the process of globalisation in Anglophone Sub-Saharan Africa. Through a literature review, an attempt is made to link science education and globalisation by answering the question: 'What influence does globalisation have on science education in countries in Anglophone Sub-Saharan Africa?' The findings of the study show some significant convergence of what is valued in science education in Sub-Saharan Africa in areas such as pedagogy; English language as a medium of instruction; assessment of learning; mobility of students in the region; and in the frameworks for collaborative engagements among stakeholders in Sub-Saharan Africa. The paper concludes with a reflective end-piece calling for more case studies to help scrutinise further the influence of globalisation on science education in Sub-Saharan Africa.

  20. Pilot testing of a membrane system for postcombustion CO<sub>2sub> capture

    Energy Technology Data Exchange (ETDEWEB)

    Merkel, Tim [Membrane Technology And Research, Incorporated, Newark, CA (United States); Kniep, Jay [Membrane Technology And Research, Incorporated, Newark, CA (United States); Wei, Xiaotong [Membrane Technology And Research, Incorporated, Newark, CA (United States); Carlisle, Trevor [Membrane Technology And Research, Incorporated, Newark, CA (United States); White, Steve [Membrane Technology And Research, Incorporated, Newark, CA (United States); Pande, Saurabh [Membrane Technology And Research, Incorporated, Newark, CA (United States); Fulton, Don [Membrane Technology And Research, Incorporated, Newark, CA (United States); Watson, Robert [Membrane Technology And Research, Incorporated, Newark, CA (United States); Hoffman, Thomas [Membrane Technology And Research, Incorporated, Newark, CA (United States); Freeman, Brice [Membrane Technology And Research, Incorporated, Newark, CA (United States); Baker, Richard [Membrane Technology And Research, Incorporated, Newark, CA (United States)

    2015-09-30

    This final report summarizes work conducted for the U.S. Department of Energy, National Energy Technology Laboratory (DOE) to scale up an efficient post-combustion CO<sub>2sub> capture membrane process to the small pilot test stage (award number DE-FE0005795). The primary goal of this research program was to design, fabricate, and operate a membrane CO<sub>2sub> capture system to treat coal-derived flue gas containing 20 tonnes CO<sub>2sub>/day (20 TPD). Membrane Technology and Research (MTR) conducted this project in collaboration with Babcock and Wilcox (B&W), the Electric Power Research Institute (EPRI), WorleyParsons (WP), the Illinois Sustainable Technology Center (ISTC), Enerkem (EK), and the National Carbon Capture Center (NCCC). In addition to the small pilot design, build and slipstream testing at NCCC, other project efforts included laboratory membrane and module development at MTR, validation field testing on a 1 TPD membrane system at NCCC, boiler modeling and testing at B&W, a techno-economic analysis (TEA) by EPRI/WP, a case study of the membrane technology applied to a ~20 MWe power plant by ISTC, and an industrial CO<sub>2sub> capture test at an Enerkem waste-to-biofuel facility. The 20 TPD small pilot membrane system built in this project successfully completed over 1,000 hours of operation treating flue gas at NCCC. The Polaris™ membranes used on this system demonstrated stable performance, and when combined with over 10,000 hours of operation at NCCC on a 1 TPD system, the risk associated with uncertainty in the durability of postcombustion capture membranes has been greatly reduced. Moreover, next-generation Polaris membranes with higher performance and lower cost were validation tested on the 1 TPD system. The 20 TPD system also demonstrated successful operation of a new low-pressure-drop sweep module that will reduce parasitic energy losses at full scale by as much as 10 MWe. In modeling and pilot boiler testing, B&W confirmed the

  1. Effects of Multimedia and Schema Induced Analogical Reasoning on Science Learning

    Science.gov (United States)

    Zheng, R. Z.; Yang, W.; Garcia, D.; McCadden, E. P.

    2008-01-01

    The present study investigates the effects of multimedia and schema induced analogical reasoning on science learning. It involves 89 fourth grade elementary students in the north-east of the United States. Participants are randomly assigned into four conditions: (a) multimedia with analogy; (b) multimedia without analogy; (c) analogy without…

  2. Development of a Biological Science Quantitative Reasoning Exam (BioSQuaRE)

    Science.gov (United States)

    Stanhope, Liz; Ziegler, Laura; Haque, Tabassum; Le, Laura; Vinces, Marcelo; Davis, Gregory K.; Zieffler, Andrew; Brodfuehrer, Peter; Preest, Marion; Belitsky, Jason M.; Umbanhowar, Charles, Jr.; Overvoorde, Paul J.

    2017-01-01

    Multiple reports highlight the increasingly quantitative nature of biological research and the need to innovate means to ensure that students acquire quantitative skills. We present a tool to support such innovation. The Biological Science Quantitative Reasoning Exam (BioSQuaRE) is an assessment instrument designed to measure the quantitative…

  3. Determinants of adolescent pregnancy in sub-Saharan Africa: a systematic review

    OpenAIRE

    Yakubu, Ibrahim; Salisu, Waliu Jawula

    2018-01-01

    Background Adolescent pregnancy has been persistently high in sub-Saharan Africa. The objective of this review is to identify factors influencing adolescent pregnancies in sub-Saharan Africa in order to design appropriate intervention program. Methods A search in MEDLINE, Scopus, Web of science, and Google Scholar databases with the following keywords: determinants, factors, reasons, sociocultural factors, adolescent pregnancy, unintended pregnancies, and sub- Saharan Africa. Qualitative and ...

  4. Forensic science: the truth is out there

    Science.gov (United States)

    Herold, Lynne D.

    2002-06-01

    Criminalistics, one of the many sub-divisions of forensic science, is an applied science in which items of evidence are analyzed to provide investigative information and scientific evidence to be used in courts of law. Laboratories associated with governmental public agencies are typically involved in criminal cases as opposed to civil cases, and those types of cases that fall within the jurisdiction of the particular agency. Common analytical divisions within criminalistics laboratories include blood alcohol testing, toxicology, narcotics, questioned documents, biology, firearms, latent fingerprints, physical and trace evidence sections. Specialized field investigative services may be provided in the areas of clandestine drug laboratories and major crimes (firearms, biology, trace, arson/explosives). Forensic science best practice requires the use of non-destructive testing whenever reasonably possible. Several technically difficult situations (bodies and evidence encased in cement and metal) are presented as a challenge to audience.

  5. Paraconsistency, Pluralistic Models and Reasoning in Climate Science

    Directory of Open Access Journals (Sweden)

    Bryson Brown

    2018-05-01

    Full Text Available Scientific inquiry is typically focused on particular questions about particular objects and properties.  This leads to a multiplicity of models which, even when they draw on a single, consistent body of concepts and principles, often employ different methods and assumptions to model different systems.  Pluralists have remarked on how scientists draw on different assumptions to model different systems, different aspects of systems and systems under different conditions and defended the value of distinct, incompatible models within science at any given time. (Cartwright, 1999; Chang, 2012 Paraconsistentists have proposed logical strategies to avoid trivialization when inconsistencies arise by a variety of means.(Batens, 2001; Brown, 1990; Brown, 2002  Here we examine how chunk and permeate, a simple approach to paraconsistent reasoning which avoids heterodox logic by confining commitments to separate contexts in which reasoning with them is taken to be reliable while allowing ‘permeation’ of some conclusions into other contexts, can help to systematize pluralistic reasoning across the boundaries of plural contexts, using regional climate models as an example.(Benham et al., 2014; Brown & Priest 2004, 2015  The result is a kind of unity for science—but a unity achieved by the constrained exchange of specified information between different contexts, rather than the closure of all commitments under some paraconsistent consequence relation. 

  6. Construction and Evaluation of Reliability and Validity of Reasoning Ability Test

    Science.gov (United States)

    Bhat, Mehraj A.

    2014-01-01

    This paper is based on the construction and evaluation of reliability and validity of reasoning ability test at secondary school students. In this paper an attempt was made to evaluate validity, reliability and to determine the appropriate standards to interpret the results of reasoning ability test. The test includes 45 items to measure six types…

  7. Data science in R a case studies approach to computational reasoning and problem solving

    CERN Document Server

    Nolan, Deborah

    2015-01-01

    Effectively Access, Transform, Manipulate, Visualize, and Reason about Data and ComputationData Science in R: A Case Studies Approach to Computational Reasoning and Problem Solving illustrates the details involved in solving real computational problems encountered in data analysis. It reveals the dynamic and iterative process by which data analysts approach a problem and reason about different ways of implementing solutions. The book's collection of projects, comprehensive sample solutions, and follow-up exercises encompass practical topics pertaining to data processing, including: Non-standar

  8. Pilot test and optimization of plasma based DeNO{sub x}. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Stamate, E.; Chen, W.; Michelsen, P.K. (Risoe DTU. PLF, Roskilde (Denmark)); Joergensen, L.; Jensen, T.K.; Kristensen, P.G.; Tobiasen, L.; Simonsen, P. (Dansk Gasteknisk Center, Hoersholm (Denmark))

    2010-12-15

    A technique for NO{sub x} reduction for combustion processes was examined. The technique is based on injecting ozone into the NO{sub x} containing flue gas where it will react with NO{sub x}, forming an anhydride of nitric acid, N{sub 2}O{sub 5}. N{sub 2}O{sub 5} is easily removed later using a water scrubber. The technique was tested on a gas engine based CHP unit and a CHP unit based on a straw-fired boiler and a steam turbine. It was found that: 1) NO{sub x} emissions can be reduced by more than 95 % by adding ozone to the flue gas; 2) The technique is applicable on flue gas from biomass combustion despite the presence of compounds such as SO{sub 2} and HCl; 3) Reduction of NO{sub x} emissions requires approximately half as much O{sub 3} when it is applied to the natural gas fired engine unit compared to the straw-fired boiler unit; 4) The higher O{sub 3} consumption on straw-fired units is due both to higher flue gas temperature and to larger NO{sub x} fluctuations in the flue gas compared to the gas engine unit; 5) For the gas engine unit the formaldehyde emission was reduced by 60%; 6) SO{sub 2} emissions are eliminated by the deNO{sub x} unit. It can be concluded that at present the plasma deNO{sub x} process suffers from too high capital and operating costs and too low plant operating time to be an attractive alternative for gas engine CHP plants. Furthermore, there is only a small gap of approx. 25 % between the specific ozone consumption obtained at the pilot test in Ringsted and the theoretically achievable value. This difference is too small to have a major impact on process economy in case of an optimized deNO{sub x} process. At straw fired plants the technology tends to be more promising for several reasons: 1) Significant potential for optimizing specific ozone consumption. 2) Larger NO{sub x} reduction due to the fact that higher concentration levels in the flue gas generate higher income from e.g. fertilizer sales. 3) Reduced or zero SO{sub 2

  9. Integrated dry NO{sub x}/SO{sub 2} emissions control system: integrated system test report

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R.A.; Muzio, L.J. [Fossil Energy Research Corp., Laguna Hills, CA (United States); Hunt, T. [Public Service Co. of Colorado, Denver, CO (United States)

    1997-04-01

    The DOE sponsored Integrated Dry NO{sub x}/SO{sub 2} Emissions Control System Program, is a Clean Coal Technology III demonstration, being conducted by Public Service Company of Colorado. The test site is Arapahoe Generating Station Unit 4, a 100 MWe, down-fired utility boiler burning a low-sulfur Western coal. The project goal is to demonstrate up to 70 percent reductions in NO{sub x} and SO{sub 2} emissions through the integration of: (1) down-fired low NO{sub x} burners with overfire air; (2) Selective Non-Catalytic Reduction (SNCR) for additional NO{sub x} removal; and (3) Dry Sorbent Injection (DSI) and duct humidification for SO{sub 2} removal. This report documents the final phase of the test program, in which the overall performance of the integrated system was evaluated. Previous testing has shown that the goal of 70 percent NO{sub x} removal was easily achieved with the combination of low-NO{sub x} burners, overfire air, and urea-based SNCR. Similarly, the ability of the sodium-based DSI system to achieve 70 percent SO{sub 2} removal was also demonstrated previously. The integrated tests demonstrated the synergistic benefit of operating the SNCR and sodium-based DSI systems concurrently. With the automatic control system set to limit the NH{sub 3} emissions to less than 8 ppm, the NO{sub 2} emissions from the sodium-based DSI system were reduced by nominally 50 percent compared to operation with the DSI system alone. Comparably, the combined operation reduced NH{sub 3} emissions, as reflected by a higher urea injection rate for a fixed NH{sub 3} emission limit. With combined DSI and SNCR operation, an ammonia odor problem was encountered around the Unit 4 ash silo (this did not occur with the SNCR system operated alone at comparable NH{sub 3} slip levels). This odor problem is attributed to the sodium changing the rate at which NH{sub 3} is released from the ash when it is wetted for truck transport to the disposal site.

  10. Reasoning with Inductive Argument Test: A Study of Validity and Reliability

    Directory of Open Access Journals (Sweden)

    Mehmet Emrah Karadere

    2013-11-01

    Full Text Available Reasoning with Inductive Argument Test:A Study of Validity and Reliability Objective: The aim of our study is to research reliability and validity and to evaluate the usability of Turkish version of Reasoning with Inductive Argument Test (RIAT in Turkish healty population. Method: 51 healty volunteers who work in Ankara Dıskapi Yildirim Beyazit Research and Training Hospital participated in this study. Reasoning with Inductive Argument Test (RIAT was translated into Turkish by three clinical good knowledge of English. Participants were given a sociodemographic data form, and RIAT were performed by clinicians. To test the reliability of the Turkish version of RIAT, Cronbach’s alpha coefficient was calculated and the halving method was used for the test. Results: The internal consistency of the Reasoning with Inductive Argument Test (RIAT items, Cronbach’s alpha internal consistency coefficient measurements of 0.73 was found to be statistically significant. Spearman-Brown coefficient that determines the reliability of the whole test r=0.74 was found. Kurtosis values of all the items was below 1.5 and the percentages in the second evaluation were mainly lower. At the same time, both change in belief between self produced RIAT options and given RIAT options (p=0.02, z=-2296 as well as changes in beliefs between related and unrelated items for Obsessive Compulsive Disorder (OCD difference (p=0.03, z=-2.199 were significant. Conclusion: The preliminary data obtained from the study of reliability and validity of the scale shows that ‘Reasoning with Inductive Argument Test’ supports reliability and validity in Turkish population.

  11. The Priority of the Question: Focus Questions for Sustained Reasoning in Science

    Science.gov (United States)

    Lustick, David

    2010-08-01

    Science education standards place a high priority on promoting the skills and dispositions associated with inquiry at all levels of learning. Yet, the questions teachers employ to foster sustained reasoning are most likely borrowed from a textbook, lab manual, or worksheet. Such generic questions generated for a mass audience, lack authenticity and contextual cues that allow learners to immediately appreciate a question’s relevance. Teacher queries intended to motivate, guide, and foster learning through inquiry are known as focus questions. This theoretical article draws upon science education research to present a typology and conceptual framework intended to support science teacher educators as they identify, develop, and evaluate focus questions with their students.

  12. Nuclear Test-Experimental Science

    International Nuclear Information System (INIS)

    Struble, G.L.; Donohue, M.L.; Bucciarelli, G.; Hymer, J.D.; Kirvel, R.D.; Middleton, C.; Prono, J.; Reid, S.; Strack, B.

    1988-01-01

    Fiscal year 1988 has been a significant, rewarding, and exciting period for Lawrence Livermore National Laboratory's nuclear testing program. It was significant in that the Laboratory's new director chose to focus strongly on the program's activities and to commit to a revitalized emphasis on testing and the experimental science that underlies it. It was rewarding in that revolutionary new measurement techniques were fielded on recent important and highly complicated underground nuclear tests with truly incredible results. And it was exciting in that the sophisticated and fundamental problems of weapons science that are now being addressed experimentally are yielding new challenges and understanding in ways that stimulate and reward the brightest and best of scientists. During FY88 the program was reorganized to emphasize our commitment to experimental science. The name of the program was changed to reflect this commitment, becoming the Nuclear Test-Experimental Science (NTES) Program

  13. Examining the Features of Earth Science Logical Reasoning and Authentic Scientific Inquiry Demonstrated in a High School Earth Science Curriculum: A Case Study

    Science.gov (United States)

    Park, Do-Yong; Park, Mira

    2013-01-01

    The purpose of this study was to investigate the inquiry features demonstrated in the inquiry tasks of a high school Earth Science curriculum. One of the most widely used curricula, Holt Earth Science, was chosen for this case study to examine how Earth Science logical reasoning and authentic scientific inquiry were related to one another and how…

  14. The nano-science of C sub 6 0 molecule

    CERN Document Server

    Rafii-Tabar, H

    2002-01-01

    Over the past few years, nano-science and its associated nano-technology have emerged into prominence in research institutions across the world. They have brought about new scientific and engineering paradigms, allowing for the manipulation of single atoms and molecules, designing and fabricating new materials, atom-by-atom, and devices that operate on significantly reduced time and length scales. One important area of research in nano-science and nano technology is carbon-based physics in the form of fullerene physics. The C sub 6 0 molecule, and other cage-like fullerenes, together with carbon nano tubes provide objects that can be combined to generate three-dimensional functional structures for use in the anticipated nano-technology of future. The unique properties of C sub 6 0 can also be exploited in designing nano-phase thin films with applications in nano-scope device technology and processes such as nano-lithography. This requires a deep understanding of the highly complex process of adsorption of thi...

  15. High performance Li{sub 3}V{sub 2}(PO{sub 4}){sub 3}/C composite cathode material for lithium ion batteries studied in pilot scale test

    Energy Technology Data Exchange (ETDEWEB)

    Chen Zhenyu [School of Chemical Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China); Dai Changsong, E-mail: changsd@hit.edu.c [School of Chemical Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China); Wu Gang; Nelson, Mark [Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Hu Xinguo [School of Chemical Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China); Zhang Ruoxin; Liu Jiansheng; Xia Jicai [Battery Material Business Division, Guangzhou Tinci Materials Technology Co., Ltd., Guangzhou 510760 (China)

    2010-12-01

    Li{sub 3}V{sub 2}(PO{sub 4}){sub 3}/C composite cathode material was synthesized via carbothermal reduction process in a pilot scale production test using battery grade raw materials with the aim of studying the feasibility for their practical applications. XRD, FT-IR, XPS, CV, EIS and battery charge-discharge tests were used to characterize the as-prepared material. The XRD and FT-IR data suggested that the as-prepared Li{sub 3}V{sub 2}(PO{sub 4}){sub 3}/C material exhibits an orderly monoclinic structure based on the connectivity of PO{sub 4} tetrahedra and VO{sub 6} octahedra. Half cell tests indicated that an excellent high-rate cyclic performance was achieved on the Li{sub 3}V{sub 2}(PO{sub 4}){sub 3}/C cathodes in the voltage range of 3.0-4.3 V, retaining a capacity of 95% (96 mAh/g) after 100 cycles at 20C discharge rate. The low-temperature performance of the cathode was further evaluated, showing 0.5C discharge capacity of 122 and 119 mAh/g at -25 and -40 {sup o}C, respectively. The discharge capacity of graphite//Li{sub 3}V{sub 2}(PO{sub 4}){sub 3} batteries with a designed battery capacity of 14 Ah is as high as 109 mAh/g with a capacity retention of 92% after 224 cycles at 2C discharge rates. The promising high-rate and low-temperature performance observed in this work suggests that Li{sub 3}V{sub 2}(PO{sub 4}){sub 3}/C is a very strong candidate to be a cathode in a next-generation Li-ion battery for electric vehicle applications.

  16. Testing primary-school children's understanding of the nature of science.

    Science.gov (United States)

    Koerber, Susanne; Osterhaus, Christopher; Sodian, Beate

    2015-03-01

    Understanding the nature of science (NOS) is a critical aspect of scientific reasoning, yet few studies have investigated its developmental beginnings and initial structure. One contributing reason is the lack of an adequate instrument. Two studies assessed NOS understanding among third graders using a multiple-select (MS) paper-and-pencil test. Study 1 investigated the validity of the MS test by presenting the items to 68 third graders (9-year-olds) and subsequently interviewing them on their underlying NOS conception of the items. All items were significantly related between formats, indicating that the test was valid. Study 2 applied the same instrument to a larger sample of 243 third graders, and their performance was compared to a multiple-choice (MC) version of the test. Although the MC format inflated the guessing probability, there was a significant relation between the two formats. In summary, the MS format was a valid method revealing third graders' NOS understanding, thereby representing an economical test instrument. A latent class analysis identified three groups of children with expertise in qualitatively different aspects of NOS, suggesting that there is not a single common starting point for the development of NOS understanding; instead, multiple developmental pathways may exist. © 2014 The British Psychological Society.

  17. The bounds of reason game theory and the unification of the behavioral sciences

    CERN Document Server

    Gintis, Herbert

    2014-01-01

    Game theory is central to understanding human behavior and relevant to all of the behavioral sciences-from biology and economics, to anthropology and political science. However, as The Bounds of Reason demonstrates, game theory alone cannot fully explain human behavior and should instead complement other key concepts championed by the behavioral disciplines. Herbert Gintis shows that just as game theory without broader social theory is merely technical bravado, so social theory without game theory is a handicapped enterprise. This edition has been thoroughly revised and updated. Reinvigorati

  18. H{sub 2} assisted NH{sub 3}-SCR over Ag/Al{sub 2}O{sub 3} for automotive applications

    Energy Technology Data Exchange (ETDEWEB)

    Fogel, S.

    2013-05-15

    The up-coming strict emission legislation demands new and improved catalysts for diesel vehicle deNO{sub x}. The demand for low-temperature activity is especially challenging. H{sub 2}-assisted NH{sub 3}-SCR over Ag/Al{sub 2}O{sub 3} has shown a very promising low-temperature activity and a combination of Ag/Al{sub 2}O{sub 3} and Fe-BEA can give a high NO{sub x} conversion in a broad temperature window without the need to dose H{sub 2} at higher temperatures. The aim of this study has been to investigate the combined Ag/Al{sub 2}O{sub 3} and Fe-BEA catalyst system both at laboratory-scale and in full-scale engine bench testing. The catalysts were combined both in a sequential dual-bed layout and a dual-layer layout where the catalysts were coated on top of each other. The Ag/Al{sub 2}O{sub 3} catalyst was also investigated with the aim of improving the sulphur tolerance and low-temperature activity by testing different alumina-supports. A large focus of this study has been the preparation of monolithic catalyst bricks for the catalyst testing. A high SBET and higher Ag loading gave a high sulphur tolerance and activity. It was believed that the high S{sub BET} is needed to give a higher NH{sub 3} adsorption capacity, necessary for the SCR reaction. A higher Ag loading gives more Ag sites and probably a favourable Ag dispersion. Testing with sulphur gave an increased activity of the catalysts. Testing of monolithic catalysts showed a similar activity enhancement after a few standard test cycles. A change in the dispersion or state of Ag can be possible reasons for the activation seen and the activation was believed to be related to Ag and not the alumina. Small-scale laboratory testing showed that it was preferred to have Ag/Al{sub 2}O{sub 3} either upstream or as the outer layer of Fe-BEA. This was attributed to complete NH{sub 3} oxidation over Fe-BEA giving a deficit of NH{sub 3} over the Ag/Al{sub 2}O{sub 3} if it was placed downstream or as the inner layer

  19. Mechanical resistance of UO{sub 2} pellet by means of free-fall-impact testing

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Tae-sik; Lee, Seung-jae; Kim, Jae-ik; Jo, Young-ho; Park, Bo-yong; Ko, Sang-ern [KEPCO NF, Daejeon (Korea, Republic of)

    2014-10-15

    A fuel rod failed during a power transient can be seen in Fig 1. and conjunction of a chipped pellet with a cladding crack has been observed in commercial reactors through the post-irradiation examinations. It revealed that missing-pellet-surface(MPS) was one of the reasons of the fuel failure. The mechanism of this failure mode that MPS induces the asymmetry of the pellet-cladding mechanical system mainly comprises a stress concentration at the inner surface resulting in non-classical PCI. The fracture toughness is largely close to material property. It is assumed that by optimizing surface design of UO{sub 2} pellet, the strength arises because theoretical strength is considerably affected by geometry as one of a parameter of factor 'f'. Pellet research for design optimization to achieve better resistance to external load should be accompanied with volumetric approach to the improvement of mechanical behavior of pellet being still ongoing. At this work, the resistance to external load is analyzed varying with the geometry of pellets and angles of impact on UO{sub 2} pellet surface by the free-fall-impact test method. The tested specimens were equivalently produced and sintered for having the same volumetric property such as sinter density and grain size expect the surface with different geometry design at the end face and shoulder which includes dish, chamfer and land in dimension and angle. Missing-pellet-surface(MPS) on UO{sub 2} pellet is inevitable behavior during manufacturing, handling and burning in reactor and brings about non-classical PCI behavior that could damage fuel rod integrity. For this reason, the free-fall-drop tester was developed by KEPCO NF Material Development laboratory in Daejeon for quantitatively investigating the mechanical behavior of UO{sub 2}. The free-fall-impact test is performed by dropping hammer on pellet shoulder with certain impact energy and at various angles. The result is quantitatively measured with weighing

  20. Good fences make for good neighbors but bad science: a review of what improves Bayesian reasoning and why.

    Science.gov (United States)

    Brase, Gary L; Hill, W Trey

    2015-01-01

    Bayesian reasoning, defined here as the updating of a posterior probability following new information, has historically been problematic for humans. Classic psychology experiments have tested human Bayesian reasoning through the use of word problems and have evaluated each participant's performance against the normatively correct answer provided by Bayes' theorem. The standard finding is of generally poor performance. Over the past two decades, though, progress has been made on how to improve Bayesian reasoning. Most notably, research has demonstrated that the use of frequencies in a natural sampling framework-as opposed to single-event probabilities-can improve participants' Bayesian estimates. Furthermore, pictorial aids and certain individual difference factors also can play significant roles in Bayesian reasoning success. The mechanics of how to build tasks which show these improvements is not under much debate. The explanations for why naturally sampled frequencies and pictures help Bayesian reasoning remain hotly contested, however, with many researchers falling into ingrained "camps" organized around two dominant theoretical perspectives. The present paper evaluates the merits of these theoretical perspectives, including the weight of empirical evidence, theoretical coherence, and predictive power. By these criteria, the ecological rationality approach is clearly better than the heuristics and biases view. Progress in the study of Bayesian reasoning will depend on continued research that honestly, vigorously, and consistently engages across these different theoretical accounts rather than staying "siloed" within one particular perspective. The process of science requires an understanding of competing points of view, with the ultimate goal being integration.

  1. Explicitly Targeting Pre-Service Teacher Scientific Reasoning Abilities and Understanding of Nature of Science through an Introductory Science Course

    Science.gov (United States)

    Koenig, Kathleen; Schen, Melissa; Bao, Lei

    2012-01-01

    Development of a scientifically literate citizenry has become a national focus and highlights the need for K-12 students to develop a solid foundation of scientific reasoning abilities and an understanding of nature of science, along with appropriate content knowledge. This implies that teachers must also be competent in these areas; but…

  2. Software Testing as Science

    Directory of Open Access Journals (Sweden)

    Ingrid Gallesdic

    2013-06-01

    Full Text Available The most widespread opinion among people who have some connection with software testing is that this activity is an art. In fact, books have been published widely whose titles refer to it as art, role or process. But because software complexity is increasing every year, this paper proposes a new approach, conceiving the test as a science. This is because the processes by which they are applied are the steps of the scientific method: inputs, processes, outputs. The contents of this paper examines the similarities and test characteristics as science.

  3. Assessment in Science Education

    Science.gov (United States)

    Rustaman, N. Y.

    2017-09-01

    An analyses study focusing on scientific reasoning literacy was conducted to strengthen the stressing on assessment in science by combining the important of the nature of science and assessment as references, higher order thinking and scientific skills in assessing science learning as well. Having background in developing science process skills test items, inquiry in its many form, scientific and STEM literacy, it is believed that inquiry based learning should first be implemented among science educators and science learners before STEM education can successfully be developed among science teachers, prospective teachers, and students at all levels. After studying thoroughly a number of science researchers through their works, a model of scientific reasoning was proposed, and also simple rubrics and some examples of the test items were introduced in this article. As it is only the beginning, further studies will still be needed in the future with the involvement of prospective science teachers who have interests in assessment, either on authentic assessment or in test items development. In balance usage of alternative assessment rubrics, as well as valid and reliable test items (standard) will be needed in accelerating STEM education in Indonesia.

  4. Monitoring progression of clinical reasoning skills during health sciences education using the case method - a qualitative observational study.

    Science.gov (United States)

    Orban, Kristina; Ekelin, Maria; Edgren, Gudrun; Sandgren, Olof; Hovbrandt, Pia; Persson, Eva K

    2017-09-11

    Outcome- or competency-based education is well established in medical and health sciences education. Curricula are based on courses where students develop their competences and assessment is also usually course-based. Clinical reasoning is an important competence, and the aim of this study was to monitor and describe students' progression in professional clinical reasoning skills during health sciences education using observations of group discussions following the case method. In this qualitative study students from three different health education programmes were observed while discussing clinical cases in a modified Harvard case method session. A rubric with four dimensions - problem-solving process, disciplinary knowledge, character of discussion and communication - was used as an observational tool to identify clinical reasoning. A deductive content analysis was performed. The results revealed the students' transition over time from reasoning based strictly on theoretical knowledge to reasoning ability characterized by clinical considerations and experiences. Students who were approaching the end of their education immediately identified the most important problem and then focused on this in their discussion. Practice knowledge increased over time, which was seen as progression in the use of professional language, concepts, terms and the use of prior clinical experience. The character of the discussion evolved from theoretical considerations early in the education to clinical reasoning in later years. Communication within the groups was supportive and conducted with a professional tone. Our observations revealed progression in several aspects of students' clinical reasoning skills on a group level in their discussions of clinical cases. We suggest that the case method can be a useful tool in assessing quality in health sciences education.

  5. Reason, Science, Criticism. Joseph Agassi interviewed on his 90th birthday by Zuzana Parusniková

    Czech Academy of Sciences Publication Activity Database

    Parusniková, Zuzana; Agassi, J.

    2017-01-01

    Roč. 24, č. 4 (2017), s. 526-545 ISSN 1335-0668 Institutional support: RVO:67985955 Keywords : Joseph Agassi * interview Subject RIV: AA - Philosophy ; Religion http://klemens.sav.sk/fiusav/organon/?q=sk/reason- science -criticism

  6. Genetic and environmental influences on analogical and categorical verbal and spatial reasoning in 12-year old twins.

    Science.gov (United States)

    Mosing, Miriam A; Mellanby, Jane; Martin, Nicholas G; Wright, Margaret J

    2012-09-01

    Research on the genetic influences on different abstract reasoning skills (fluid intelligence) and their interrelation (especially in childhood/adolescence) has been sparse. A novel cognitive test battery, the Verbal and Spatial Reasoning test for Children (VESPARCH 1), consisting of four matched (in terms of test-procedure and design) subtests assessing verbal [analogical (VA) and categorical (VC)] and spatial [analogical (SA) and categorical (SC)] reasoning, was administered to a population based sample of 12-year old twins (169 pairs). Multivariate analysis was conducted to explore the genetic relationship between the four cognitive sub-domains. Heritabilities were 0.62 (VA), 0.49 (VC), 0.52 (SA), and 0.20 (SC). Genetic influences were due to one common factor with no specific genetic influences. This shared genetic factor also explained almost the entire covariance between the domains, as environmental variance was largely specific to each subtest. The finding of no genetic influences specific to each subtest may be due to the uniquely matched design of the VESPARCH 1, reducing confoundment of different test modalities used in conventional tests. For future research or when interpreting previous studies, our findings highlight the importance of taking such potential artefacts (i.e. different test modalities for different sub-domains) into account when exploring the relationship between cognitive sub-domains.

  7. Labelled T{sub 3}, T{sub 4} and TBP for In Vitro Testing of Thyroid Function in Man and Animals

    Energy Technology Data Exchange (ETDEWEB)

    Czerniak, P.; Boruchowski, Sabina; Shomron, I. [Dept. of Radiotherapy and Isotopes, Tel-Hashomer Hospital, Tel-Aviv University Medical School, Faculty of Continuing Medical Education, Tel-Aviv (Israel)

    1970-02-15

    Iodothyronines are bound to determined electrophoretic fractions of serum proteins - TBP (TBG, TBA, TBPA). Radioiodine labelled T{sub 3} and T{sub 4} complex the free TBP fractions until saturation. The excess of added in vitro thyronines is then absorbed by the RBC. The changes described can be detected and quantitatively determined by radioisotope tests: radioelectrophoresis - T{sub 3/4} BP test, and RBC - {sup 125}I T{sub 3} test (Hamolsky test). The in vitro tests of the thyroid function can be clinically reliable if the protein fractions are normal, and they may be altered without thyroid pathology if the TBG fractions are abnormal. The electrophoretic fractions vary quantitatively and qualitatively in animals of different classes and orders. We chose these features to study the correlation between iodothyronines, plasma proteins and the above-mentioned thyroid tests. Twenty-two animal species (arranged according to the increasing percentage of the Hamolsky test) were examined: goat (8.6%, cow, lamb, calf, man, camel, goose, hamster, rat, turkey, marmot, duck, horse, donkey, hen, dog, pigeon, rabbit, guinea-pig, mouse, fish and frog (91.5%). The following additional parameters were examined: PBI, serum quantitative electrophoresis, T{sub 3} BP studies. All the tests were performed under identical technical conditions. Results and conclusions: (1) The Hamolsky test in the examined animals ranges from 9% to 92%. It is highest in the poicolothermics, in which much prealbumin and few glubulins are found on electrophoresis. The T{sub 3} BP is low, and about a half of the added {sup 125}I T{sub 3} remains unbound. (2) T{sub 3} and T{sub 4} are complexed with T{sub 3} BP and T{sub 4} BP fractions, which correspond to prealbumin, albumin, alpha 1-2, beta and exceptionally gamma globulin. The fractions are variable but characteristic for each animal species. T{sub 3} BP does not correlate exactly with T{sub 4} BP, and seems to be distributed over more fractions

  8. Measuring Reasoning about Teaching for Graduate Admissions in Psychology and Related Disciplines

    OpenAIRE

    Robert J. Sternberg; Karin Sternberg; Rebel J. E. Todhunter

    2017-01-01

    Teaching- and teaching-evaluation skills are critically important to professional success in psychology and related disciplines. We explored the possibility of measuring reasoning-about-teaching skills as a supplementary measure for admissions in psychology and related behavioral-sciences disciplines. We tested 103 students for their reasoning about teaching and their reasoning about research, as well as for their cognitive- (abstract reasoning) and educational skills. We found that women per...

  9. Understanding the Complex Relationship between Critical Thinking and Science Reasoning among Undergraduate Thesis Writers

    Science.gov (United States)

    Dowd, Jason E.; Thompson, Robert J., Jr.; Schif, Leslie A.; Reynolds, Julie A.

    2018-01-01

    Developing critical-thinking and scientific reasoning skills are core learning objectives of science education, but little empirical evidence exists regarding the interrelationships between these constructs. Writing effectively fosters students' development of these constructs, and it offers a unique window into studying how they relate. In this…

  10. Exploring High School Students Beginning Reasoning about Significance Tests with Technology

    Science.gov (United States)

    García, Víctor N.; Sánchez, Ernesto

    2017-01-01

    In the present study we analyze how students reason about or make inferences given a particular hypothesis testing problem (without having studied formal methods of statistical inference) when using Fathom. They use Fathom to create an empirical sampling distribution through computer simulation. It is found that most student´s reasoning rely on…

  11. The Relationship between Environmental Moral Reasoning and Environmental Attitudes of Pre-Service Science Teachers

    Science.gov (United States)

    Tuncay, Busra; Yilmaz-Tuzun, Ozgul; Tuncer-Teksoz, Gaye

    2011-01-01

    The aim of the present study was to investigate the relationship between environmental moral reasoning patterns and environmental attitudes of 120 pre-service science teachers. Content analysis was carried out on participants' written statements regarding their concerns about the presented environmental problems and the statements were labeled as…

  12. The Design and Use of Planetary Science Video Games to Teach Content while Enhancing Spatial Reasoning Skills

    Science.gov (United States)

    Ziffer, Julie; Nadirli, Orkhan; Rudnick, Benjamin; Pinkham, Sunny; Montgomery, Benjamin

    2016-10-01

    Traditional teaching of Planetary Science requires students to possess well developed spatial reasoning skills (SRS). Recent research has demonstrated that SRS, long known to be crucial to math and science success, can be improved among students who lack these skills (Sorby et al., 2009). Teaching spatial reasoning is particularly valuable to women and minorities who, through societal pressure, often doubt their abilities (Hill et al., 2010). To address SRS deficiencies, our team is developing video games that embed SRS training into Planetary Science content. Our first game, on Moon Phases, addresses the two primary challenges faced by students trying to understand the Sun-Earth-Moon system: 1) visualizing the system (specifically the difference between the Sun-Earth orbital plane and the Earth-Moon orbital plane) and 2) comprehending the relationship between time and the position-phase of the Moon. In our second video game, the student varies an asteroid's rotational speed, shape, and orientation to the light source while observing how these changes effect the resulting light curve. To correctly pair objects to their light curves, students use spatial reasoning skills to imagine how light scattering off a three dimensional rotating object is imaged on a sensor plane and is then reduced to a series of points on a light curve plot. These two games represent the first of our developing suite of high-interest video games designed to teach content while increasing the student's competence in spatial reasoning.

  13. Detection Test for Leakage of CO{sub 2} into Sodium Loop

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sun Hee; Wi, Myung-Hwan; Min, Jae Hong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    This report is about the facility for the detection test for leakage of CO{sub 2} into sodium loop. The facility for the detection test for leakage of CO{sub 2} into sodium loop was introduced. The test will be carried out. Our experimental results are going to be expected to be used for approach methods to detect CO{sub 2} leaking into sodium in heat exchangers. A sodium-and-carbon dioxide (Na-CO{sub 2}) heat exchanger is one of the key components for the supercritical CO{sub 2} Brayton cycle power conversion system of sodium-cooled fast reactors (SFRs). A printed circuit heat exchanger (PCHE) is considered for the Na-CO{sub 2} heat exchanger, which is known to have potential for reducing the volume occupied by the exchangers compared to traditional shell-and-tube heat exchangers. Among various issues about the Na- CO{sub 2} exchanger, detection of CO{sub 2} leaking into sodium in the heat exchanger is most important thing for its safe operation. It is known that reaction products from sodium and CO{sub 2} such as sodium carbonate (Na{sub 2}CO{sub 3}) and amorphous carbon are hardly soluble in sodium, which cause plug sodium channels. Detection technique for Na{sub 2}CO{sub 3} in sodium loop has not been developed yet. Therefore, detection of CO{sub 2} and CO from reaction of sodium and CO{sub 2} are proper to detect CO{sub 2} leakage into sodium loop.

  14. Evolutions in clinical reasoning assessment: The Evolving Script Concordance Test.

    Science.gov (United States)

    Cooke, Suzette; Lemay, Jean-François; Beran, Tanya

    2017-08-01

    Script concordance testing (SCT) is a method of assessment of clinical reasoning. We developed a new type of SCT case design, the evolving SCT (E-SCT), whereby the patient's clinical story is "evolving" and with thoughtful integration of new information at each stage, decisions related to clinical decision-making become increasingly clear. We aimed to: (1) determine whether an E-SCT could differentiate clinical reasoning ability among junior residents (JR), senior residents (SR), and pediatricians, (2) evaluate the reliability of an E-SCT, and (3) obtain qualitative feedback from participants to help inform the potential acceptability of the E-SCT. A 12-case E-SCT, embedded within a 24-case pediatric SCT (PaedSCT), was administered to 91 pediatric residents (JR: n = 50; SR: n = 41). A total of 21 pediatricians served on the panel of experts (POE). A one-way analysis of variance (ANOVA) was conducted across the levels of experience. Participants' feedback on the E-SCT was obtained with a post-test survey and analyzed using two methods: percentage preference and thematic analysis. Statistical differences existed across levels of training: F = 19.31 (df = 2); p decision-making process. The E-SCT demonstrated very good reliability and was effective in distinguishing clinical reasoning ability across three levels of experience. Participants found the E-SCT engaging and representative of real-life clinical reasoning and decision-making processes. We suggest that further refinement and utilization of the evolving style case will enhance SCT as a robust, engaging, and relevant method for the assessment of clinical reasoning.

  15. The Quantitative Reasoning for College Science (QuaRCS) Assessment: Emerging Themes from 5 Years of Data

    Science.gov (United States)

    Follette, Katherine; Dokter, Erin; Buxner, Sanlyn

    2018-01-01

    The Quantitative Reasoning for College Science (QuaRCS) Assessment is a validated assessment instrument that was designed to measure changes in students' quantitative reasoning skills, attitudes toward mathematics, and ability to accurately assess their own quantitative abilities. It has been administered to more than 5,000 students at a variety of institutions at the start and end of a semester of general education college science instruction. I will begin by briefly summarizing our published work surrounding validation of the instrument and identification of underlying attitudinal factors (composite variables identified via factor analysis) that predict 50% of the variation in students' scores on the assessment. I will then discuss more recent unpublished work, including: (1) Development and validation of an abbreviated version of the assessment (The QuaRCS Light), which results in marked improvements in students' ability to maintain a high effort level throughout the assessment and has broad implications for quantitative reasoning assessments in general, and (2) Our efforts to revise the attitudinal portion of the assessment to better assess math anxiety level, another key factor in student performance on numerical assessments.

  16. Dual-Process Theories of Reasoning: The Test of Development

    Science.gov (United States)

    Barrouillet, Pierre

    2011-01-01

    Dual-process theories have become increasingly influential in the psychology of reasoning. Though the distinction they introduced between intuitive and reflective thinking should have strong developmental implications, the developmental approach has rarely been used to refine or test these theories. In this article, I review several contemporary…

  17. Novel Inorganic/Polymer Composite Membranes for CO<sub>2sub> Capture

    Energy Technology Data Exchange (ETDEWEB)

    Ho, W.S. Winston [The Ohio State Univ., Columbus, OH (United States). Depts. of Chemical and Biomolecular Engineering, Chemistry, and Materials Science and Engineering; Dutta, Prabir K. [The Ohio State Univ., Columbus, OH (United States). Depts. of Chemical and Biomolecular Engineering, Chemistry, and Materials Science and Engineering; Schmit, Steve J. [Gradient Technology, Elk River, MN (United States)

    2016-10-01

    The objective of this project is to develop a cost-effective design and manufacturing process for new membrane modules that capture CO<sub>2sub> from flue gas in coal-fired power plants. The membrane consisted of a thin selective layer including inorganic (zeolite) embedded in a polymer structure so that it can be made in a continuous manufacturing process. The membrane was incorporated in spiral-wound modules for the field test with actual flue gas at the National Carbon Capture Center (NCCC) in Wilsonville, AL and bench scale tests with simulated flue gas at the Ohio State University (OSU). Using the modules for post-combustion CO<sub>2sub> capture is expected to achieve the DOE target of $40/tonne CO<sub>2sub> captured (in 2007 dollar) for 2025. Membranes with the amine-containing polymer cover layer on zeolite-Y (ZY) nanoparticles deposited on the polyethersulfone (PES) substrate were successfully synthesized. The membranes showed a high CO<sub>2sub> permeance of about 1100 GPU (gas permeation unit, 1 GPU = 10-6 cm3 (STP)/(cm2 • s • cm Hg), 3000 GPU = 10-6 mol/(m2 • s • Pa)) with a high CO<sub>2sub>/N>2sub> selectivity of > 200 at the typical flue gas conditions at 57°C (about 17% water vapor in feed gas) and > 1400 GPU CO<sub>2sub> permeance with > 500 CO<sub>2sub>/N>2sub> selectivity at 102°C (~ 80% water vapor). The synthesis of ZY nanoparticles was successfully scaled up, and the pilot-scale membranes were also successfully fabricated using the continuous membrane machine at OSU. The transport performance of the pilot-scale membranes agreed reasonably well with the lab-scale membranes. The results from both the lab-scale and scale-up membranes were used for the techno-economic analysis. The scale-up membranes were fabricated into prototype spiral-wound membrane modules for continuous testing with simulated or real flue gas. For real flue gas testing, we worked with NCCC, in

  18. Tests of α{sub s} running from QCD fits to collider data

    Energy Technology Data Exchange (ETDEWEB)

    Kuprash, Oleg; Geiser, Achim [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Hamburg University, Institute of Experimental Physics, Hamburg (Germany)

    2015-07-01

    The running of the strong coupling constant, α{sub s}(μ), is tested in a QCD analysis using jet measurements at LHC, Tevatron and HERA in combination with inclusive DIS data. Here μ is associated with the energy scale in the process, typically with the jet transverse energy. For the α{sub s} running test, the parameter n{sub f} of the running, which gives the number of active quarks contributing to loop corrections of the jet and DIS cross sections, is replaced by n{sub f} + Δn{sub f} at energy scales greater than μ > μ{sub thresh}. A series of simultaneous α{sub s}(M{sub Z}) + Δn{sub f} + proton PDF fits to world collider cross section data is done at Next-to-Leading Order QCD, for μ{sub thresh} values ranging from 1 GeV to 1 TeV. The fitted Δn{sub f} is consistent with zero at all tested scales, which gives a precise quantitative confirmation of the QCD running of α{sub s} over 3 orders of magnitude in energy scale. The presented study also provides a new way for indirect searches of the physics beyond the Standard Model.

  19. Puzzling with potential: dynamic testing of analogical reasoning in children

    OpenAIRE

    Stevenson, Claire Elisabeth

    2012-01-01

    Assessment procedures are frequent in children's school careers; however, measuring potential for learning has remained a puzzle. Dynamic testing is a method to assess cognitive potential that includes training in the assessment process. The goal of this thesis project was to develop a new dynamic test of analogical reasoning for school children. The main aims were to (1) investigate factors that influence children’s differences in performance and change during dynamic testing and (2) examine...

  20. Explanatory item response modelling of an abstract reasoning assessment: A case for modern test design

    OpenAIRE

    Helland, Fredrik

    2016-01-01

    Assessment is an integral part of society and education, and for this reason it is important to know what you measure. This thesis is about explanatory item response modelling of an abstract reasoning assessment, with the objective to create a modern test design framework for automatic generation of valid and precalibrated items of abstract reasoning. Modern test design aims to strengthen the connections between the different components of a test, with a stress on strong theory, systematic it...

  1. The Quantitative Reasoning for College Science (QuaRCS) Assessment in non-Astro 101 Courses II

    Science.gov (United States)

    Kirkman, Thomas W.; Jensen, Ellen

    2017-06-01

    The Quantitative Reasoning for College Science (QuaRCS) Assessment[1] aims to measure the pre-algebra mathematical skills that are often part of "general education" science courses like Astro 101. In four majors STEM classes, we report comparisons between QuaRCS metrics, ACT math, GPAO, and the course grade. In three of four classes QuaRCS QR score and ACT math were statistically significantly correlated (with r˜.6), however in the fourth course —a senior-level microbiology course— there was no statistically significantly correlation (in fact, rPhysics courses showed fractional sigma gains in QR, self-estimated math fluency and math importance, but not all of those increases were statistically significant. Using a QuaRCS map relating the questions to skill areas, we found graph reading, percentages, and proportional reasoning to be the most misunderstood skills in all four courses.[1] QuaRCS, Follette, et al.,2015, DOI: http://dx.doi.org/10.5038/1936-4660.8.2.2

  2. Measuring Reasoning about Teaching for Graduate Admissions in Psychology and Related Disciplines

    Directory of Open Access Journals (Sweden)

    Robert J. Sternberg

    2017-11-01

    Full Text Available Teaching- and teaching-evaluation skills are critically important to professional success in psychology and related disciplines. We explored the possibility of measuring reasoning-about-teaching skills as a supplementary measure for admissions in psychology and related behavioral-sciences disciplines. We tested 103 students for their reasoning about teaching and their reasoning about research, as well as for their cognitive- (abstract reasoning and educational skills. We found that women performed better than men on our reasoning-about-teaching measure, and that factorially, our reasoning-about-teaching measure clustered with our reasoning-about-research measures but not with our measures of abstract cognitive reasoning and educational skills.

  3. Towards a Philosophically and a Pedagogically Reasonable Nature of Science Curriculum

    Science.gov (United States)

    Yacoubian, Hagop Azad

    This study, primarily theoretical in nature, explores a philosophically and pedagogically reasonable way of addressing nature of science (NOS) in school science. NOS encompasses what science is and how scientific knowledge develops. I critically evaluate consensus frameworks of NOS in school science, which converge contentious philosophical viewpoints into general NOS-related ideas. I argue that they (1) lack clarity in terms of how NOS-related ideas could be applied for various ends, (2) portray a distorted image of the substantive content of NOS and the process of its development, and (3) lack a developmental trajectory for how to address NOS at different grade levels. As a remedy to these problems, I envision a NOS curriculum that (1) explicates and targets both NOS as an educational end and NOS as a means for socioscientific decision making, (2) has critical thinking as its foundational pillar, and (3) provides a developmental pathway for NOS learning using critical thinking as a progression unit. Next, I illustrate a framework for addressing NOS in school science referred to as the critical thinking—nature of science (CT-NOS) framework. This framework brings together the first two of the three elements envisioned in the NOS curriculum. I address the third element by situating the CT-NOS framework in a developmental context, borrowing from the literature on learning progressions in science and using critical thinking as a progression unit. Finally, I present an empirical study of experienced secondary science teachers’ views of a NOS lesson prepared using the CT-NOS framework. The teachers attended a professional development workshop at which the lesson, and the characteristics of the CT-NOS framework, were presented. The analysis of the qualitative data revealed that most teachers found the lesson to be somewhat feasible for a secondary science classroom, useful or somewhat useful to their students, and interesting. The teachers focused on 14 features of

  4. Informal reasoning regarding socioscientific issues: The influence of morality and content knowledge

    Science.gov (United States)

    Sadler, Troy Dow

    This study focused on informal reasoning regarding socioscientific issues. It explored how morality and content knowledge influenced the negotiation and resolution of contentious and complex scenarios based on genetic engineering. Two hundred and sixty-nine undergraduate students completed a quantitative test of genetics concepts. A sub-set of the students (n = 30) who completed this instrument and represented divergent levels of content knowledge participated in two individual interviews, during which they discussed their ideas, reactions, and solutions to three gene therapy scenarios and three cloning scenarios. A mixed-methods approach was used to examine patterns of informal reasoning and the influence of morality, the effects of content knowledge on the use of informal reasoning patterns, and the effects of content knowledge on the quality of informal reasoning. Students demonstrated evidence of rationalistic, emotive, and intuitive forms of informal reasoning. Rationalistic informal reasoning described reason-based considerations; emotive informal reasoning described care-based considerations; and intuitive reasoning described considerations based on immediate reactions to the context of a scenario. Participants frequently relied on combinations of these reasoning patterns as they worked to resolve individual socioscientific scenarios. Most of the participants appreciated at least some of the moral implications of their decisions, and these considerations were typically interwoven within an overall pattern of informal reasoning. Although differences in content knowledge were not found to be related to modes of informal reasoning (rationalistic, emotive, and informal), data did indicate that differences in content knowledge were related to variations in informal reasoning quality. Participants, with more advanced understandings of genetics, demonstrated fewer instances of reasoning flaws, as defined by a priori criteria (intra-scenario coherence, inter

  5. Assessment Guide for Educators: A Content Comparison--2002 Series Test and the Current GED® Test

    Science.gov (United States)

    GED Testing Service, 2017

    2017-01-01

    This report provides a content comparison for the 2002 Series GED® test and the current GED® for the following test topic areas: (1) Mathematical Reasoning; (2) Reasoning through Language Arts; (3) Science; and (4) Social Studies.

  6. Estimation of post-test probabilities by residents: Bayesian reasoning versus heuristics?

    Science.gov (United States)

    Hall, Stacey; Phang, Sen Han; Schaefer, Jeffrey P; Ghali, William; Wright, Bruce; McLaughlin, Kevin

    2014-08-01

    Although the process of diagnosing invariably begins with a heuristic, we encourage our learners to support their diagnoses by analytical cognitive processes, such as Bayesian reasoning, in an attempt to mitigate the effects of heuristics on diagnosing. There are, however, limited data on the use ± impact of Bayesian reasoning on the accuracy of disease probability estimates. In this study our objective was to explore whether Internal Medicine residents use a Bayesian process to estimate disease probabilities by comparing their disease probability estimates to literature-derived Bayesian post-test probabilities. We gave 35 Internal Medicine residents four clinical vignettes in the form of a referral letter and asked them to estimate the post-test probability of the target condition in each case. We then compared these to literature-derived probabilities. For each vignette the estimated probability was significantly different from the literature-derived probability. For the two cases with low literature-derived probability our participants significantly overestimated the probability of these target conditions being the correct diagnosis, whereas for the two cases with high literature-derived probability the estimated probability was significantly lower than the calculated value. Our results suggest that residents generate inaccurate post-test probability estimates. Possible explanations for this include ineffective application of Bayesian reasoning, attribute substitution whereby a complex cognitive task is replaced by an easier one (e.g., a heuristic), or systematic rater bias, such as central tendency bias. Further studies are needed to identify the reasons for inaccuracy of disease probability estimates and to explore ways of improving accuracy.

  7. Thermal stability test of UO{sub 2}-doped pellet manufactured at INB

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Diogo R., E-mail: diogoribeiro@inb.gov.br [Indústrias Nucleares do Brasil S.A. (FCN/INB), Resende, RJ (Brazil). Fábrica de Combustível Nuclear; Freitas, Artur C., E-mail: artur.freitas@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

    2017-07-01

    The thermal stability test of UO{sub 2}-doped pellet manufactured at INB was carried out in order to analyze the resintering behavior. This analysis is fundamental for predicting dimensional behavior during irradiation. INB commonly performs resintering test to qualify its production lots, and the same methodology was applied to UO{sub 2}-doped pellets. In this preliminary study, three sets of experiments have been made: 1) without any chemical additive (Z test, the standard UO{sub 2} pellets - undoped); 2) UO{sub 2} pellets doped with 0.1, 0.2 and 0.3 wt% of Al{sub 2}O{sub 3}; and 3) 0.1, 0.2 and 0.3 wt% of Nb{sub 2}O{sub 5}. The preliminary results showed an increase in sintered density in all resintering experiments. So as to obtain the percentage increase, the theoretical densities (g/cm{sup 3} and %TD) were calculated based on the undoped UO{sub 2} pellets. All samples increased in a range of 0.27 to 0.32 %TD the out-pile densification during the resintering process. However, the Z(Nb)3 test showed the lowest value of 0.08 %TD, which is not in agreement with the INB specification limits. The sintered density of this test (0.3 wt% niobia) was 96.15% TD. This fact might be related to the competitive mechanism between Kirkendall effect, forming porosity owing to niobium solubilization on UO{sub 2} matrix, and densification process as a result of uranium diffusivity. Thus, the densification was only 0.08 %TD in Z(Nb)3 sample. All the other samples were in agreement with INB specification. (author)

  8. R<sub>5sub>T>4sub> compounds - unique multifunctional intermetallics for basic research and applications

    Energy Technology Data Exchange (ETDEWEB)

    Mudryk, Yaroslav

    2016-10-01

    The unique properties of the rare-earth elements and their alloys have brought them from relative obscurity to high profile use in common high-tech applications. The broad technological impact of these remarkable materials may have never been known by the general public if not for the supply concerns that placed the rare-earth materials on the front page of newspapers and magazines. Neodymium and dysprosium, two essential components of Nd<sub>2sub>Fe>14sub>B-based high-performance permanent magnets, have drawn much attention and have been deemed critical materials for many energy-related applications. Ironically, the notoriety of rare-earth elements and their alloys is the result of a global movement to reduce their use in industrial applications and, thus, ease concerns about their supply and ultimately to reduce their position in high-tech supply chains. Research into the applications of lanthanide alloys has been de-emphasized recently due to the perception that industry is moving away from the use of rare-earth elements in new products. While lanthanide supply challenges justify efforts to diversify the supply chain, a strategy to completely replace the materials overlooks the reasons rare earths became important in the first place -- their unique properties are too beneficial to ignore. Rare-earth alloys and compounds possess truly exciting potential for basic science exploration and application development such as solid-state caloric cooling. In this brief review, we touch upon several promising systems containing lanthanide elements that show important and interesting magnetism-related phenomena.

  9. Evidence that logical reasoning depends on conscious processing.

    Science.gov (United States)

    DeWall, C Nathan; Baumeister, Roy F; Masicampo, E J

    2008-09-01

    Humans, unlike other animals, are equipped with a powerful brain that permits conscious awareness and reflection. A growing trend in psychological science has questioned the benefits of consciousness, however. Testing a hypothesis advanced by [Lieberman, M. D., Gaunt, R., Gilbert, D. T., & Trope, Y. (2002). Reflection and reflexion: A social cognitive neuroscience approach to attributional inference. Advances in Experimental Social Psychology, 34, 199-249], four studies suggested that the conscious, reflective processing system is vital for logical reasoning. Substantial decrements in logical reasoning were found when a cognitive load manipulation preoccupied conscious processing, while hampering the nonconscious system with consciously suppressed thoughts failed to impair reasoning (Experiment 1). Nonconscious activation (priming) of the idea of logical reasoning increased the activation of logic-relevant concepts, but failed to improve logical reasoning performance (Experiments 2a-2c) unless the logical conclusions were largely intuitive and thus not reliant on logical reasoning (Experiment 3). Meanwhile, stimulating the conscious goal of reasoning well led to improvements in reasoning performance (Experiment 4). These findings offer evidence that logical reasoning is aided by the conscious, reflective processing system.

  10. Learning Scientific Reasoning Skills May Be Key to Retention in Science, Technology, Engineering, and Mathematics

    Science.gov (United States)

    Jensen, Jamie L.; Neeley, Shannon; Hatch, Jordan B.; Piorczynski, Ted

    2017-01-01

    The United States produces too few Science, Technology, Engineering, and Mathematics (STEM) graduates to meet demand. We investigated scientific reasoning ability as a possible factor in STEM retention. To do this, we classified students in introductory biology courses at a large private university as either declared STEM or non-STEM majors and…

  11. Analysis of statistical misconception in terms of statistical reasoning

    Science.gov (United States)

    Maryati, I.; Priatna, N.

    2018-05-01

    Reasoning skill is needed for everyone to face globalization era, because every person have to be able to manage and use information from all over the world which can be obtained easily. Statistical reasoning skill is the ability to collect, group, process, interpret, and draw conclusion of information. Developing this skill can be done through various levels of education. However, the skill is low because many people assume that statistics is just the ability to count and using formulas and so do students. Students still have negative attitude toward course which is related to research. The purpose of this research is analyzing students’ misconception in descriptive statistic course toward the statistical reasoning skill. The observation was done by analyzing the misconception test result and statistical reasoning skill test; observing the students’ misconception effect toward statistical reasoning skill. The sample of this research was 32 students of math education department who had taken descriptive statistic course. The mean value of misconception test was 49,7 and standard deviation was 10,6 whereas the mean value of statistical reasoning skill test was 51,8 and standard deviation was 8,5. If the minimal value is 65 to state the standard achievement of a course competence, students’ mean value is lower than the standard competence. The result of students’ misconception study emphasized on which sub discussion that should be considered. Based on the assessment result, it was found that students’ misconception happen on this: 1) writing mathematical sentence and symbol well, 2) understanding basic definitions, 3) determining concept that will be used in solving problem. In statistical reasoning skill, the assessment was done to measure reasoning from: 1) data, 2) representation, 3) statistic format, 4) probability, 5) sample, and 6) association.

  12. VUV testing of science cameras at MSFC: QE measurement of the CLASP flight cameras

    Science.gov (United States)

    Champey, P.; Kobayashi, K.; Winebarger, A.; Cirtain, J.; Hyde, D.; Robertson, B.; Beabout, B.; Beabout, D.; Stewart, M.

    2015-08-01

    The NASA Marshall Space Flight Center (MSFC) has developed a science camera suitable for sub-orbital missions for observations in the UV, EUV and soft X-ray. Six cameras were built and tested for the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP), a joint MSFC, National Astronomical Observatory of Japan (NAOJ), Instituto de Astrofisica de Canarias (IAC) and Institut D'Astrophysique Spatiale (IAS) sounding rocket mission. The CLASP camera design includes a frame-transfer e2v CCD57-10 512 × 512 detector, dual channel analog readout and an internally mounted cold block. At the flight CCD temperature of -20C, the CLASP cameras exceeded the low-noise performance requirements (UV, EUV and X-ray science cameras at MSFC.

  13. The Relationship between Environmental Moral Reasoning and Environmental Attitudes of Pre-Service Science Teachers

    OpenAIRE

    TUNCAY, Busra; YILMAZ-TUZUN, Ozgul; TUNCER-TEKSOZ, Gaye

    2011-01-01

    The aim of the present study was to investigate the relationship between environmental moral reasoning patterns and environmental attitudes of 120 pre-service science teachers. Content analysis was carried out on participants’ written statements regarding their concerns about the presented environmental problems and the statements were labeled as ecocentric, anthropocentric, and non-environmental according to their meanings. Then, descriptive and inferential analyses were conducted ...

  14. Superlattice-like SnSb{sub 4}/Ga{sub 3}Sb{sub 7} thin films for ultrafast switching phase-change memory application

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Yifeng [Tongji University, Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, Functional Materials Research Laboratory, School of Materials Science and Engineering, Shanghai (China); Jiangsu University of Technology, School of Mathematics and Physics, Changzhou (China); He, Zifang; Zhai, Jiwei [Tongji University, Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, Functional Materials Research Laboratory, School of Materials Science and Engineering, Shanghai (China); Wu, Pengzhi; Lai, Tianshu [Sun Yat-Sen University, State Key Laboratory of Optoelectronic Materials and Technology, Department of Physics, Guangzhou (China); Song, Sannian; Song, Zhitang [Chinese Academy of Sciences, State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Micro-system and Information Technology, Shanghai (China)

    2015-11-15

    The carrier concentration of Sb-rich phase SnSb{sub 4}, Ga{sub 3}Sb{sub 7} and superlattice-like [SnSb{sub 4}(3.5 nm)/Ga{sub 3}Sb{sub 7}(4 nm)]{sub 7} (SLL-7) thin films as a function of annealing temperature was investigated to explain the reason of resistance change. The activation energy for crystallization was calculated with a Kissinger equation to estimate the thermal stability. In order to illuminate the transition mechanisms, the crystallization kinetics of SLL-7 were explored by using Johnson-Mehl-Avrami theory. The obtained values of Avrami indexes indicate that a one-dimensional growth-dominated mechanism is responsible for the set transition of SLL-7 thin film. X-ray diffractometer and Raman scattering spectra were recorded to investigate the change of crystalline structure. The measurement of atomic force microscopy indicated that SLL-7 thin film has a good smooth surface. A picosecond laser pump-probe system was used to test and verify phase-change speed of the SLL-7 thin film. (orig.)

  15. Why Citizen Science Without Usability Testing Will Underperform

    Science.gov (United States)

    Romano, C.; Gay, P.; Owens, R.; Burlea, G.

    2017-12-01

    Citizen science projects must undergo usability testing and optimization if they are to meet their stated goals. This presentation will include video of usability tests conducted upon citizen science websites. Usability testing is essential to the success of online interaction, however, citizen science projects have just begun to include this critical activity. Interaction standards in citizen science lag behind those of commercial interests, and published research on this topic is limited. Since online citizen science is by definition, an exchange of information, a clear understanding of how users experience an online project is essential to informed decision-making. Usability testing provides that insight. Usability testing collects data via direct observation of a person while she interacts with a digital product, such as a citizen science website. The test participant verbalizes her thoughts while using the website or application; the moderator follows the participant and captures quantitative measurement of the participant's confidence of success as she advances through the citizen science project. Over 15 years of usability testing, we have observed that users who do not report a consistent sense of progress are likely to abandon a website after as few as three unrewarding interactions. Since citizen science is also a voluntary activity, ensuring seamless interaction for users is mandatory. Usability studies conducted on citizen science websites demonstrate that project teams frequently underestimate a user's need for context and ease of use. Without usability testing, risks to online citizen science projects include high bounce rate (users leave the website without taking any action), abandonment (of the website, tutorials, registration), misunderstanding instructions (causing disorientation and erroneous conclusions), and ultimately, underperforming projects.

  16. Development of abbreviated eight-item form of the Penn Verbal Reasoning Test.

    Science.gov (United States)

    Bilker, Warren B; Wierzbicki, Michael R; Brensinger, Colleen M; Gur, Raquel E; Gur, Ruben C

    2014-12-01

    The ability to reason with language is a highly valued cognitive capacity that correlates with IQ measures and is sensitive to damage in language areas. The Penn Verbal Reasoning Test (PVRT) is a 29-item computerized test for measuring abstract analogical reasoning abilities using language. The full test can take over half an hour to administer, which limits its applicability in large-scale studies. We previously described a procedure for abbreviating a clinical rating scale and a modified procedure for reducing tests with a large number of items. Here we describe the application of the modified method to reducing the number of items in the PVRT to a parsimonious subset of items that accurately predicts the total score. As in our previous reduction studies, a split sample is used for model fitting and validation, with cross-validation to verify results. We find that an 8-item scale predicts the total 29-item score well, achieving a correlation of .9145 for the reduced form for the model fitting sample and .8952 for the validation sample. The results indicate that a drastically abbreviated version, which cuts administration time by more than 70%, can be safely administered as a predictor of PVRT performance. © The Author(s) 2014.

  17. Development of Abbreviated Eight-Item Form of the Penn Verbal Reasoning Test

    Science.gov (United States)

    Bilker, Warren B.; Wierzbicki, Michael R.; Brensinger, Colleen M.; Gur, Raquel E.; Gur, Ruben C.

    2014-01-01

    The ability to reason with language is a highly valued cognitive capacity that correlates with IQ measures and is sensitive to damage in language areas. The Penn Verbal Reasoning Test (PVRT) is a 29-item computerized test for measuring abstract analogical reasoning abilities using language. The full test can take over half an hour to administer, which limits its applicability in large-scale studies. We previously described a procedure for abbreviating a clinical rating scale and a modified procedure for reducing tests with a large number of items. Here we describe the application of the modified method to reducing the number of items in the PVRT to a parsimonious subset of items that accurately predicts the total score. As in our previous reduction studies, a split sample is used for model fitting and validation, with cross-validation to verify results. We find that an 8-item scale predicts the total 29-item score well, achieving a correlation of .9145 for the reduced form for the model fitting sample and .8952 for the validation sample. The results indicate that a drastically abbreviated version, which cuts administration time by more than 70%, can be safely administered as a predictor of PVRT performance. PMID:24577310

  18. Can Science Test Supernatural Worldviews?

    Science.gov (United States)

    Fishman, Yonatan I.

    2009-01-01

    Several prominent scientists, philosophers, and scientific institutions have argued that science cannot test supernatural worldviews on the grounds that (1) science presupposes a naturalistic worldview (Naturalism) or that (2) claims involving supernatural phenomena are inherently beyond the scope of scientific investigation. The present paper…

  19. Preliminary Studies of Na{sub 2}CO{sub 3} Cleaning from Na-CO{sub 2} Interaction in S-CO{sub 2} Power Cycle coupled to SFR System

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Hwa-Young; Lee, Jeong Ik [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Wi, Myung-Hwan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Ahn, Hong Joo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    Once the flow channel is plugged, to replace the plugged channel, the whole system operation should be stopped or a bypass system is necessary.. Therefore, finding a material which can clean up the solid reaction products from Na-CO{sub 2} interaction and the contaminated system with little or no impact on economics can be a valuable research. Hence, a screening process of selecting candidate materials was adopted to find a potential substance which can act as a cleaning agent in the previous study. It is essential to ensure the system economics as well as safety of SFR coupled with S-CO{sub 2} Brayton power conversion system. For this reason, the experiment was conducted to see the possibility of reaction between each selected potential substance and Na{sub 2}CO{sub 3}, which is the major product of the reaction. Na{sub 2}CO{sub 3} does not melt before 856 .deg. C This study was performed with the collaboration of Korea Atomic Energy Research Institute (KAERI) and Korea Advanced Institute of Science and Technology (KAIST). Liquid sodium and CO{sub 2} gas would react then produce the solid reaction products when the pressure boundary of sodium-CO{sub 2} heat exchanger fails. The solid reaction products are possible to plug the narrow flow channel of PCHE and this concerns the system economics. Thus, it is necessary to search a method for cleaning the solid reaction products which is mainly Na{sub 2}CO{sub 3}. From the preliminary study, some sodium-based compounds were selected and the mixtures of several sodium-based compounds with Na{sub 2}CO{sub 3} were thermally analyzed by the TG/DTA studies. Unfortunately, the selected sodium-based compounds, NaBrO{sub 3}, NaClO{sub 3} and NaBF{sub 4}, decomposed before 600 .deg. C and did not react with Na{sub 2}CO{sub 3}. In the near future, further research will be performed to search other compounds for cleaning the solid reaction products.

  20. The Impact of an Interdisciplinary Learning Community Course on Pseudoscientific Reasoning in First-Year Science Students

    Science.gov (United States)

    Franz, Timothy M.; Green, Kris H.

    2013-01-01

    This case study examined the development and evaluation of an interdisciplinary first-year learning community designed to stimulate scientific reasoning and critical thinking. Designed to serve the needs of scholarship students majoring in mathematics and natural sciences, the six-credit learning community course was writing-intensive and…

  1. An Examination of the Influence of Globalisation on Science Education in Anglophone Sub-Saharan Africa

    Science.gov (United States)

    Koosimile, Anthony T.; Suping, Shanah M.

    2015-01-01

    This paper takes the view that the emergence of some trends and practices in science education mirrors the influence of the process of globalisation in Anglophone Sub-Saharan Africa. Through a literature review, an attempt is made to link science education and globalisation by answering the question: "What influence does globalisation have on…

  2. Gender-related differences in reasoning skills and learning interests of junior high school students

    Science.gov (United States)

    Shemesh, Michal

    The purpose of this study was to investigate gender-related differences in the relationship between the development of formal reasoning skills and learning interests during the early adolescent stage. For this purpose, 249 students, from seventh to ninth grade, were assessed for their level of mastery of formal reasoning skills by a test based on videotaped simple experiments. Learning interests were assessed by a written response to an open question. Results showed that adolescent boys develop patterns of formal reasoning before their girl classmates. In addition, boys tend to prefer science and technology subjects, while girls tend to prefer language, social studies, and humanities. Analysis of interactions showed that boys' tendency toward science and technology is positively correlated to their age and development of formal reasoning, while girls' tendency to the above subjects is positively related to their development of formal reasoning capacity, but inversely related to their age. Possible explanations to the above-described findings and suggestions for instructional modes that may increase girls' interest in science and technology are discussed.

  3. Scientific Reasoning and Its Relationship with Problem Solving: The Case of Upper Primary Science Teachers

    Science.gov (United States)

    Alshamali, Mahmoud A.; Daher, Wajeeh M.

    2016-01-01

    This study aimed at identifying the levels of scientific reasoning of upper primary stage (grades 4-7) science teachers based on their use of a problem-solving strategy. The study sample (N = 138; 32 % male and 68 % female) was randomly selected using stratified sampling from an original population of 437 upper primary school teachers. The…

  4. Bench Scale Development and Testing of Aerogel Sorbents for CO<sub>2sub> Capture Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Begag, Redouane [Aspen Aerogels, Northborough, MA (United States)

    2017-03-30

    The primary objective of this project was scaling up and evaluating a novel Amine Functionalized Aerogel (AFA) sorbent in a bench scale fluidized bed reactor. The project team (Aspen Aerogels, University of Akron, ADA-ES, and Longtail Consulting) has carried out numerous tests and optimization studies to demonstrate the CO<sub>2sub> capture performance of the AFA sorbent in all its forms: powder, pellet, and bead. The CO<sub>2sub> capture target performance of the AFA sorbent (all forms) were set at > 12 wt.% and > 6 wt.% for total and working CO<sub>2sub> capacity, respectively (@ 40 °C adsorption / 100 – 120 °C desorption). The optimized AFA powders outperformed the performance targets by more than 30%, for the total CO<sub>2sub> capacity (14 - 20 wt.%), and an average of 10 % more for working CO<sub>2sub> capacity (6.6 – 7.0 wt.%, and could be as high as 9.6 wt. % when desorbed at 120 °C). The University of Akron developed binder formulations, pellet production methods, and post treatment technology for increased resistance to attrition and flue gas contaminants. In pellet form the AFA total CO<sub>2sub> capacity was ~ 12 wt.% (over 85% capacity retention of that of the powder), and there was less than 13% degradation in CO<sub>2sub> capture capacity after 20 cycles in the presence of 40 ppm SO<sub>2sub>. ADA-ES assessed the performance of the AFA powder, pellet, and bead by analyzing sorption isotherms, water uptake analysis, cycling stability, jet cup attrition and crush tests. At bench scale, the hydrodynamic and heat transfer properties of the AFA sorbent pellet in fluidized bed conditions were evaluated at Particulate Solid Research, Inc. (PSRI). After the process design requirements were completed, by Longtail Consulting LLC, a techno-economic analysis was achieved using guidance from The National Energy Technology Laboratory (NETL) report. This report provides the necessary framework to estimate costs for a temperature swing post

  5. Assessment of Scientific Reasoning as an Institutional Outcome

    Science.gov (United States)

    2016-04-01

    expertise in the outcome domain. Student achievement of the Scientific Reasoning and Principles of Science was assessed in the 2012-13 academic year by...scientific reasoning assessment. Overall, students were weakest when answering questions related to (a) proportional reasoning , (b) isolation of...variables, and (c) if-then reasoning . These findings are being incorporates into redesign of the core curriculum to enhance continuity among science courses

  6. In-pile test of Li{sub 2}TiO{sub 3} pebble bed with neutron pulse operation

    Energy Technology Data Exchange (ETDEWEB)

    Tsuchiya, K. E-mail: tsuchiya@oarai.jaeri.go.jp; Nakamichi, M.; Kikukawa, A.; Nagao, Y.; Enoeda, M.; Osaki, T.; Ioki, K.; Kawamura, H

    2002-12-01

    Lithium titanate (Li{sub 2}TiO{sub 3}) is one of the candidate materials as tritium breeder in the breeding blanket of fusion reactors, and it is necessary to show the tritium release behavior of Li{sub 2}TiO{sub 3} pebble beds. Therefore, a blanket in-pile mockup was developed and in situ tritium release experiments with the Li{sub 2}TiO{sub 3} pebble bed were carried out in the Japan Materials Testing Reactor. In this study, the relationship between tritium release behavior from Li{sub 2}TiO{sub 3} pebble beds and effects of various parameters were evaluated. The (R/G) ratio of tritium release (R) and tritium generation (G) was saturated when the temperature at the outside edge of the Li{sub 2}TiO{sub 3} pebble bed became 300 deg. C. The tritium release amount increased cycle by cycle and saturated after about 20 pulse operations.

  7. CO<sub>2sub> Storage and Enhanced Oil Recovery: Bald Unit Test Site, Mumford Hills Oil Field, Posey County, Indiana

    Energy Technology Data Exchange (ETDEWEB)

    Frailey, Scott M. [Illinois State Geological Survey, Champaign, IL (United States); Krapac, Ivan G. [Illinois State Geological Survey, Champaign, IL (United States); Damico, James R. [Illinois State Geological Survey, Champaign, IL (United States); Okwen, Roland T. [Illinois State Geological Survey, Champaign, IL (United States); McKaskle, Ray W. [Illinois State Geological Survey, Champaign, IL (United States)

    2012-03-30

    The Midwest Geological Sequestration Consortium (MGSC) carried out a small-scale carbon dioxide (CO<sub>2sub>) injection test in a sandstone within the Clore Formation (Mississippian System, Chesterian Series) in order to gauge the large-scale CO<sub>2sub> storage that might be realized from enhanced oil recovery (EOR) of mature Illinois Basin oil fields via miscible liquid CO<sub>2sub> flooding.

  8. Catalytic N<sub>2sub>O decomposition and reduction by NH<sub>3sub> over Fe/Beta and Fe/SSZ-13 catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Aiyong; Wang, Yilin; Walter, Eric D.; Kukkadapu, Ravi K.; Guo, Yanglong; Lu, Guanzhong; Weber, Robert S.; Wang, Yong; Peden, Charles H. F.; Gao, Feng

    2018-02-01

    Fe/zeolites are important N<sub>2sub>O abatement catalysts, efficient in direct N<sub>2sub>O decomposition and (selective) catalytic N<sub>2sub>O reduction. In this study, Fe/Beta and Fe/SSZ-13 were synthesized via solution ion-exchange and used to catalyze these two reactions. Nature of the Fe species was probed with UV-vis, Mössbauer and EPR spectroscopies and H2-TPR. The characterizations collectively indicate that isolated and dinuclear Fe sites dominate in Fe/SSZ-13, whereas Fe/Beta contains higher concentrations of oligomeric Fe<sub>xOy> species. H<sub>2sub>-TPR results suggest that Fe-O interactions are weaker in Fe/SSZ-13, as evidenced by the lower reduction temperatures and higher extents of autoreduction during high-temperature pretreatments in inert gas. Kinetic measurements show that Fe/SSZ-13 has higher activity in catalytic N<sub>2sub>O decomposition, thus demonstrating a positive correlation between activity and Fe-O binding, consistent with O<sub>2sub> desorption being rate-limiting for this reaction. However, Fe/Beta was found to be more active in catalyzing N<sub>2sub>O reduction by NH<sub>3sub>. This indicates that larger active ensembles (i.e., oligomers) are more active for this reaction, consistent with the fact that both N<sub>2sub>O and NH<sub>3sub> need to be activated in this case. The authors from PNNL gratefully acknowledge the US Department of Energy (DOE), Energy Efficiency and Renewable Energy, Vehicle Technologies Office for the support of this work. The research described in this paper was performed in the Environmental Molecular Sciences Laboratory (EMSL), a national scientific user facility sponsored by the DOE’s Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory (PNNL). PNNL is operated for the US DOE by Battelle. Aiyong Wang gratefully acknowledges the China Scholarship Council for the Joint-Training Scholarship Program with the Pacific

  9. Transforming Undergraduate Education Through the use of Analytical Reasoning (TUETAR)

    Science.gov (United States)

    Bishop, M. P.; Houser, C.; Lemmons, K.

    2015-12-01

    Traditional learning limits the potential for self-discovery, and the use of data and knowledge to understand Earth system relationships, processes, feedback mechanisms and system coupling. It is extremely difficult for undergraduate students to analyze, synthesize, and integrate quantitative information related to complex systems, as many concepts may not be mathematically tractable or yet to be formalized. Conceptual models have long served as a means for Earth scientists to organize their understanding of Earth's dynamics, and have served as a basis for human analytical reasoning and landscape interpretation. Consequently, we evaluated the use of conceptual modeling, knowledge representation and analytical reasoning to provide undergraduate students with an opportunity to develop and test geocomputational conceptual models based upon their understanding of Earth science concepts. This study describes the use of geospatial technologies and fuzzy cognitive maps to predict desertification across the South-Texas Sandsheet in an upper-level geomorphology course. Students developed conceptual models based on their understanding of aeolian processes from lectures, and then compared and evaluated their modeling results against an expert conceptual model and spatial predictions, and the observed distribution of dune activity in 2010. Students perceived that the analytical reasoning approach was significantly better for understanding desertification compared to traditional lecture, and promoted reflective learning, working with data, teamwork, student interaction, innovation, and creative thinking. Student evaluations support the notion that the adoption of knowledge representation and analytical reasoning in the classroom has the potential to transform undergraduate education by enabling students to formalize and test their conceptual understanding of Earth science. A model for developing and utilizing this geospatial technology approach in Earth science is presented.

  10. Relational Reasoning in Science, Medicine, and Engineering

    Science.gov (United States)

    Dumas, Denis

    2017-01-01

    This review brings together the literature that pertains to the role of relational reasoning, or the ability to discern meaningful patterns within any stream of information, in the mental work of scientists, medical doctors, and engineers. Existing studies that measure four forms of relational reasoning--analogy, anomaly, antinomy, and…

  11. Exploring the Reasons for Using Electric Books and Technologic Pedagogical and Content Knowledge of Taiwanese Elementary Mathematics and Science Teachers

    Science.gov (United States)

    Chen, Ho-Yuan; Jang, Syh-Jong

    2013-01-01

    This study highlights trends and features of E-books and their versatility of this tool in elementary educational settings. There has been little quantitative research employed to examine teachers' reasons for using or not using E-books. The purpose of this study was to examine elementary school mathematics and science teachers' reasons for using…

  12. Critical analysis of the Romanian Mathematics and Sciences school curricula based on the Romanian pupils’ results on international testing

    Directory of Open Access Journals (Sweden)

    LILIANA CIASCAI

    2009-01-01

    Full Text Available Romania occupied a back position in the international tests on Mathematics and Sciences. Teachers stress out that one possible cause of this situation could be finding on the Mathematics and Sciences curricula. This paper presents the results of the comparisons of the Romanian curricula with the curricula promoted by the international testing (PISA 2000, 2003 and 2006, and TIMSS 1995, 1999, 2003, 2007 and the curricula of the countries occupied the first places in these tests. The comparisons underline those curricula approaches, which insure success on these tests and realize the reasons of the lack of success of the Romanian pupils. These results will be presented to the curriculum makers, universities and schools, to identify the specific and transferable competencies of the pupils with success in the above-mentioned disciplines.

  13. Reasoning with Inductive Argument Test: A Study of Validity and Reliability

    Directory of Open Access Journals (Sweden)

    Mehmet Emrah Karadere

    2013-12-01

    Conclusion: The preliminary data obtained from the study of reliability and validity of the scale shows that ‘Reasoning with Inductive Argument Test’ supports reliability and validity in Turkish population. [JCBPR 2013; 2(3.000: 156-161

  14. Prediction of fracture toughness K/sub Ic/ of steel from Charpy impact test results

    Energy Technology Data Exchange (ETDEWEB)

    Iwadate, Tadao; Tanaka, Yasuhiko; Takemata, Hiroyuki; Terashima, Shuhei

    1986-08-01

    This paper presents a method to predict the fracture toughness K/sub Ic/ and/or K/sub Id/ of steels using their Charpy impact test results and tensile properties. The fracture toughness, Charpy impact and tensile properties of 2 1/4 Cr-1Mo, ASTM A508 Cl.1, A508 Cl.2 A508 Cl.3 and A533 Gr.B Cl.1 steels were measured and analysed on the basis of the excess temperature (test temperature minus FATT) and Rolfe-Novak correlation. The relationship between K/sub Ic//K/sub Ic-us/ and the excess temperature, where K/sub Ic-us/ is the upper-shelf fracture toughness K/sub Ic/ predicted by Rolfe-Novak correlation, discloses that the K/sub Ic/ transition curves of several steels are representable by only one trend curve of K/sub Ic//K/sub Ic-us/ or K/sub Id//K/sub Id-us/ versus excess temperature relation. This curve is denoted as a ''master curve''. By using this curve, the fracture toughness of steel can be predicted using Charpy impact and tensile test results. By taking account of the scattering of both the fracture toughness and Charpy impact test results, the confidence limits of the master curve were also determined. Another approach to develop more general procedure of predicting the fracture toughness K/sub Ic/ is also discussed.

  15. Climate Science for a Sustainable Energy Future Test Bed and Data Infrastructure Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Dean N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Foster, I. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Van Dam, Kerstin Kleese [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Shipman, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-05-04

    The collaborative Climate Science for a Sustainable Energy Future (CSSEF) project started in July 2011 with the goal of accelerating the development of climate model components (i.e., atmosphere, ocean and sea ice, and land surface) and enhancing their predictive capabilities while incorporating uncertainty quantification (UQ). This effort required accessing and converting observational data sets into specialized model testing and verification data sets and building a model development test bed, where model components and sub-models can be rapidly evaluated. CSSEF’s prototype test bed demonstrated, how an integrated testbed could eliminate tedious activities associated with model development and evaluation, by providing the capability to constantly compare model output—where scientists store, acquire, reformat, regrid, and analyze data sets one-by-one—to observational measurements in a controlled test bed.

  16. Bayesian Hypothesis Testing

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, Stephen A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Sigeti, David E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-11-15

    These are a set of slides about Bayesian hypothesis testing, where many hypotheses are tested. The conclusions are the following: The value of the Bayes factor obtained when using the median of the posterior marginal is almost the minimum value of the Bayes factor. The value of τ2 which minimizes the Bayes factor is a reasonable choice for this parameter. This allows a likelihood ratio to be computed with is the least favorable to H<sub>0sub>.

  17. Suppressed oxygen extraction and degradation of LiNi<sub>xMnyCozO>2sub> cathodes at high charge cut-off voltages

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Jianming; Yan, Pengfei; Zhang, Jiandong; Engelhard, Mark H.; Zhu, Zihua; Polzin, Bryant J.; Trask, Steve; Xiao, Jie; Wang, Chongmin; Zhang, Jiguang

    2017-09-01

    The capacity degradation mechanism in lithium nickel–manganese–cobalt oxide (NMC) cathodes (LiNi<sub>1/3sub>Mn>1/3sub>Co>1/3sub>O>2sub> (NMC<sub>333sub>) and LiNi<sub>0.4sub>Mn>0.4sub>Co>0.2sub>O>2sub> (NMC<sub>442sub>)) during high-voltage (cut-off of 4.8 V) operation has been investigated. In contrast to NMC<sub>442sub>, NMC<sub>333sub> exhibits rapid structural changes including severe micro-crack formation and phase transformation from a layered to a disordered rock-salt structure, as well as interfacial degradation during high-voltage cycling, leading to a rapid increase of the electrode resistance and fast capacity decline. The fundamental reason behind the poor structural and interfacial stability of NMC<sub>333sub> was found to be correlated to its high Co content and the significant overlap between the Co3+/4+ t<sub>2gsub> and O2- 2p bands, resulting in oxygen removal and consequent structural changes at high voltages. In addition, oxidation of the electrolyte solvents by the extracted oxygen species generates acidic species, which then attack the electrode surface and form highly resistive LiF. These findings highlight that both the structural and interfacial stability should be taken into account when tailoring cathode materials for high voltage battery systems.

  18. Diurnal variations in H{sub 2}O{sub 2}, O{sub 3}, PAN, HNO{sub 3} and aldehyde concentrations and NO/NO{sub 2} ratios at Rishiri Island, Japan: Potential influence from iodine chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Kanaya, Yugo [Frontier Research Center for Global Change, Japan Agency for Marine-Earth Science and Technology, 3173-25 Showa-machi, Kanazawa-ku, Yokohama, Kanagawa 236-0001 (Japan)]. E-mail: yugo@jamstec.go.jp; Tanimoto, Hiroshi [National Institute for Environmental Studies, Tsukuba (Japan); Matsumoto, Jun [Integrated Research Institute, Tokyo Institute of Technology, Yokohama (Japan); Furutani, Hiroshi [Department of Chemistry and Biochemistry, University of California, San Diego (United States); Hashimoto, Shigeru [National Institute for Environmental Studies, Tsukuba (Japan); Komazaki, Yuichi [Frontier Research Center for Global Change, Japan Agency for Marine-Earth Science and Technology, 3173-25 Showa-machi, Kanazawa-ku, Yokohama, Kanagawa 236-0001 (Japan); Tanaka, Shigeru [Department of Applied Chemistry, Keio University, Yokohama (Japan); Yokouchi, Yoko [National Institute for Environmental Studies, Tsukuba (Japan); Kato, Shungo [Department of Applied Chemistry, Graduate School of Engineering, Tokyo Metropolitan University, Hachioji (Japan); Kajii, Yoshizumi [Department of Applied Chemistry, Graduate School of Engineering, Tokyo Metropolitan University, Hachioji (Japan); Akimoto, Hajime [Frontier Research Center for Global Change, Japan Agency for Marine-Earth Science and Technology, 3173-25 Showa-machi, Kanazawa-ku, Yokohama, Kanagawa 236-0001 (Japan)

    2007-04-15

    The presence of iodine chemistry, hypothesized due to the overprediction of HO{sub 2} levels by a photochemical box model at Rishiri Island in June 2000, was quantitatively tested against the observed NO/NO{sub 2} ratios and the net production rates of ozone. The observed NO/NO{sub 2} ratios were reproduced reasonably well by considering the conversion of NO to NO{sub 2} by IO, whose amount was calculated so as to reproduce the observed HO{sub 2} levels. However, the net production rates of ozone were calculated to be negative when such high mixing ratios of IO were considered, which was inconsistent with the observed buildup of ozone during daytime. These results suggest that iodine chemistry may not be the sole mechanism for the reduced mixing ratios of HO{sub 2}, or that 'hot spots' for iodine chemistry were present. Diurnal variations in the mixing ratios of HCHO, CH{sub 3}CHO, peroxy acetyl nitrate (PAN) and HNO{sub 3} observed during the study are presented along with the simulated ones. The box model simulations suggest that the effect of iodine chemistry on these concentrations is small and that important sources of CH{sub 3}CHO and sinks of PAN are probably missing from our current understanding of the tropospheric chemistry mechanism.

  19. Consensus on measurement properties and feasibility of performance tests for the exercise and sport sciences: a Delphi study.

    Science.gov (United States)

    Robertson, Sam; Kremer, Peter; Aisbett, Brad; Tran, Jacqueline; Cerin, Ester

    2017-12-01

    Performance tests are used for multiple purposes in exercise and sport science. Ensuring that a test displays an appropriate level of measurement properties for use within a population is important to ensure confidence in test findings. The aim of this study was to obtain subject matter expert consensus on the measurement and feasibility properties that should be considered for performance tests used in the exercise and sport sciences and how these should be defined. This information was used to develop a checklist for broader dissemination. A two-round Delphi study was undertaken including 33 exercise scientists, academics and sport scientists. Participants were asked to rate the importance of a range of measurement properties relevant to performance tests in exercise and sport science. Responses were obtained in binary and Likert-scale formats, with consensus defined as achieving 67% agreement on each question. Consensus was reached on definitions and terminology for all items. Ten level 1 items (those that achieved consensus on all four questions) and nine level 2 items (those achieving consensus on ≥2 questions) were included. Both levels were included in the final checklist. The checklist developed from this study can be used to inform decision-making and test selection for practitioners and researchers in the exercise and sport sciences. This can facilitate knowledge sharing and performance comparisons across sub-disciplines, thereby improving existing field practice and research methodological quality.

  20. Validation of science virtual test to assess 8th grade students' critical thinking on living things and environmental sustainability theme

    Science.gov (United States)

    Rusyati, Lilit; Firman, Harry

    2017-05-01

    This research was motivated by the importance of multiple-choice questions that indicate the elements and sub-elements of critical thinking and implementation of computer-based test. The method used in this research was descriptive research for profiling the validation of science virtual test to measure students' critical thinking in junior high school. The participant is junior high school students of 8th grade (14 years old) while science teacher and expert as the validators. The instrument that used as a tool to capture the necessary data are sheet of an expert judgment, sheet of legibility test, and science virtual test package in multiple choice form with four possible answers. There are four steps to validate science virtual test to measure students' critical thinking on the theme of "Living Things and Environmental Sustainability" in 7th grade Junior High School. These steps are analysis of core competence and basic competence based on curriculum 2013, expert judgment, legibility test and trial test (limited and large trial test). The test item criterion based on trial test are accepted, accepted but need revision, and rejected. The reliability of the test is α = 0.747 that categorized as `high'. It means the test instruments used is reliable and high consistency. The validity of Rxy = 0.63 means that the validity of the instrument was categorized as `high' according to interpretation value of Rxy (correlation).

  1. The Linear Logistic Test Model (LLTM as the methodological foundation of item generating rules for a new verbal reasoning test

    Directory of Open Access Journals (Sweden)

    HERBERT POINSTINGL

    2009-06-01

    Full Text Available Based on the demand for new verbal reasoning tests to enrich psychological test inventory, a pilot version of a new test was analysed: the 'Family Relation Reasoning Test' (FRRT; Poinstingl, Kubinger, Skoda & Schechtner, forthcoming, in which several basic cognitive operations (logical rules have been embedded/implemented. Given family relationships of varying complexity embedded in short stories, testees had to logically conclude the correct relationship between two individuals within a family. Using empirical data, the linear logistic test model (LLTM; Fischer, 1972, a special case of the Rasch model, was used to test the construct validity of the test: The hypothetically assumed basic cognitive operations had to explain the Rasch model's item difficulty parameters. After being shaped in LLTM's matrices of weights ((qij, none of these operations were corroborated by means of the Andersen's Likelihood Ratio Test.

  2. Comparative analysis of knowledge representation and reasoning requirements across a range of life sciences textbooks.

    Science.gov (United States)

    Chaudhri, Vinay K; Elenius, Daniel; Goldenkranz, Andrew; Gong, Allison; Martone, Maryann E; Webb, William; Yorke-Smith, Neil

    2014-01-01

    Using knowledge representation for biomedical projects is now commonplace. In previous work, we represented the knowledge found in a college-level biology textbook in a fashion useful for answering questions. We showed that embedding the knowledge representation and question-answering abilities in an electronic textbook helped to engage student interest and improve learning. A natural question that arises from this success, and this paper's primary focus, is whether a similar approach is applicable across a range of life science textbooks. To answer that question, we considered four different textbooks, ranging from a below-introductory college biology text to an advanced, graduate-level neuroscience textbook. For these textbooks, we investigated the following questions: (1) To what extent is knowledge shared between the different textbooks? (2) To what extent can the same upper ontology be used to represent the knowledge found in different textbooks? (3) To what extent can the questions of interest for a range of textbooks be answered by using the same reasoning mechanisms? Our existing modeling and reasoning methods apply especially well both to a textbook that is comparable in level to the text studied in our previous work (i.e., an introductory-level text) and to a textbook at a lower level, suggesting potential for a high degree of portability. Even for the overlapping knowledge found across the textbooks, the level of detail covered in each textbook was different, which requires that the representations must be customized for each textbook. We also found that for advanced textbooks, representing models and scientific reasoning processes was particularly important. With some additional work, our representation methodology would be applicable to a range of textbooks. The requirements for knowledge representation are common across textbooks, suggesting that a shared semantic infrastructure for the life sciences is feasible. Because our representation overlaps

  3. Recognizing Mechanistic Reasoning in Student Scientific Inquiry: A Framework for Discourse Analysis Developed from Philosophy of Science

    Science.gov (United States)

    Russ, Rosemary S.; Scherr, Rachel E.; Hammer, David; Mikeska, Jamie

    2008-01-01

    Science education reform has long focused on assessing student inquiry, and there has been progress in developing tools specifically with respect to experimentation and argumentation. We suggest the need for attention to another aspect of inquiry, namely "mechanistic reasoning." Scientific inquiry focuses largely on understanding causal…

  4. Mathematics and Science Teachers' Use of and Confidence in Empirical Reasoning: Implications for STEM Teacher Preparation

    Science.gov (United States)

    Wasserman, Nicholas H.; Rossi, Dara

    2015-01-01

    The recent trend to unite mathematically related disciplines (science, technology, engineering, and mathematics) under the broader umbrella of STEM education has advantages. In this new educational context of integration, however, STEM teachers need to be able to distinguish between sufficient proof and reasoning across different disciplines,…

  5. The Life Science Exchange: a case study of a sectoral and sub-sectoral knowledge exchange programme.

    Science.gov (United States)

    Perkins, Brian Lee; Garlick, Rob; Wren, Jodie; Smart, Jon; Kennedy, Julie; Stephens, Phil; Tudor, Gwyn; Bisson, Jonathan; Ford, David V

    2016-04-27

    Local and national governments have implemented sector-specific policies to support economic development through innovation, entrepreneurship and knowledge exchange. Supported by the Welsh Government through the European Regional Development Fund, The Life Science Exchange® project was created with the aim to increase interaction between stakeholders, to develop more effective knowledge exchange mechanisms, and to stimulate the formation and maintenance of long-term collaborative relationships within the Welsh life sciences ecosystem. The Life Science Exchange allowed participants to interact with other stakeholder communities (clinical, academic, business, governmental), exchange perspectives and discover new opportunities. Six sub-sector focus groups comprising over 200 senior stakeholders from academia, industry, the Welsh Government and National Health Service were established. Over 18 months, each focus group provided input to inform healthcare innovation policy and knowledge mapping exercises of their respective sub-sectors. Collaborative projects identified during the focus groups and stakeholder engagement were further developed through sandpit events and bespoke support. Each sub-sector focus group produced a report outlining the significant strengths and opportunities in their respective areas of focus, made recommendations to overcome any 'system failures', and identified the stakeholder groups which needed to take action. A second outcome was a stakeholder-driven knowledge mapping exercise for each area of focus. Finally, the sandpit events and bespoke support resulted in participants generating more than £1.66 million in grant funding and inward investment. This article outlines four separate outcomes from the Life Science Exchange programme. The Life Science Exchange process has resulted in a multitude of collaborations, projects, inward investment opportunities and special interest group formations, in addition to securing over ten times its own

  6. Deconstructing climate misinformation to identify reasoning errors

    Science.gov (United States)

    Cook, John; Ellerton, Peter; Kinkead, David

    2018-02-01

    Misinformation can have significant societal consequences. For example, misinformation about climate change has confused the public and stalled support for mitigation policies. When people lack the expertise and skill to evaluate the science behind a claim, they typically rely on heuristics such as substituting judgment about something complex (i.e. climate science) with judgment about something simple (i.e. the character of people who speak about climate science) and are therefore vulnerable to misleading information. Inoculation theory offers one approach to effectively neutralize the influence of misinformation. Typically, inoculations convey resistance by providing people with information that counters misinformation. In contrast, we propose inoculating against misinformation by explaining the fallacious reasoning within misleading denialist claims. We offer a strategy based on critical thinking methods to analyse and detect poor reasoning within denialist claims. This strategy includes detailing argument structure, determining the truth of the premises, and checking for validity, hidden premises, or ambiguous language. Focusing on argument structure also facilitates the identification of reasoning fallacies by locating them in the reasoning process. Because this reason-based form of inoculation is based on general critical thinking methods, it offers the distinct advantage of being accessible to those who lack expertise in climate science. We applied this approach to 42 common denialist claims and find that they all demonstrate fallacious reasoning and fail to refute the scientific consensus regarding anthropogenic global warming. This comprehensive deconstruction and refutation of the most common denialist claims about climate change is designed to act as a resource for communicators and educators who teach climate science and/or critical thinking.

  7. Performance-based alternative assessments as a means of eliminating gender achievement differences on science tests

    Science.gov (United States)

    Brown, Norman Merrill

    1998-09-01

    Historically, researchers have reported an achievement difference between females and males on standardized science tests. These differences have been reported to be based upon science knowledge, abstract reasoning skills, mathematical abilities, and cultural and social phenomena. This research was designed to determine how mastery of specific science content from public school curricula might be evaluated with performance-based assessment models, without producing gender achievement differences. The assessment instruments used were Harcourt Brace Educational Measurement's GOALSsp°ler: A Performance-Based Measure of Achievement and the performance-based portion of the Stanford Achievement Testspcopyright, Ninth Edition. The identified independent variables were test, gender, ethnicity, and grade level. A 2 x 2 x 6 x 12 (test x gender x ethnicity x grade) factorial experimental design was used to organize the data. A stratified random sample (N = 2400) was selected from a national pool of norming data: N = 1200 from the GOALSsp°ler group and N = 1200 from the SAT9spcopyright group. The ANOVA analysis yielded mixed results. The factors of test, gender, ethnicity by grade, gender by grade, and gender by grade by ethnicity failed to produce significant results (alpha = 0.05). The factors yielding significant results were ethnicity, grade, and ethnicity by grade. Therefore, no significant differences were found between female and male achievement on these performance-based assessments.

  8. REASON for Europa

    Science.gov (United States)

    Moussessian, A.; Blankenship, D. D.; Plaut, J. J.; Patterson, G. W.; Gim, Y.; Schroeder, D. M.; Soderlund, K. M.; Grima, C.; Young, D. A.; Chapin, E.

    2015-12-01

    The science goal of the Europa multiple flyby mission is to "explore Europa to investigate its habitability". One of the primary instruments selected for the scientific payload is a multi-frequency, multi-channel ice penetrating radar system. This "Radar for Europa Assessment and Sounding: Ocean to Near-surface (REASON)" would revolutionize our understanding of Europa's ice shell by providing the first direct measurements of its surface character and subsurface structure. REASON addresses key questions regarding Europa's habitability, including the existence of any liquid water, through the innovative use of radar sounding, altimetry, reflectometry, and plasma/particles analyses. These investigations require a dual-frequency radar (HF and VHF frequencies) instrument with concurrent shallow and deep sounding that is designed for performance robustness in the challenging environment of Europa. The flyby-centric mission configuration is an opportunity to collect and transmit minimally processed data back to Earth and exploit advanced processing approaches developed for terrestrial airborne data sets. The observation and characterization of subsurface features beneath Europa's chaotic surface require discriminating abundant surface clutter from a relatively weak subsurface signal. Finally, the mission plan also includes using REASON as a nadir altimeter capable of measuring tides to test ice shell and ocean hypotheses as well as characterizing roughness across the surface statistically to identify potential follow-on landing sites. We will present a variety of measurement concepts for addressing these challenges.

  9. A Longitudinal Study of the Effects of Undergraduate Training on Reasoning.

    Science.gov (United States)

    Lehman, Darrin R.; Nisbett, Richard E.

    1990-01-01

    Effects of undergraduate training on inductive reasoning and logic were examined. Social science training produced significant effects on statistical and methodological reasoning. Natural science and humanities training produced significant effects on conditional logic reasoning. Results indicate that reasoning is taught and generalizable. (BC)

  10. Examining Teacher Framing, Student Reasoning, and Student Agency in School-Based Citizen Science

    Science.gov (United States)

    Harris, Emily Mae

    This dissertation presents three interrelated studies examining opportunities for student learning through contributory citizen science (CS), where students collect and contribute data to help generate new scientific knowledge. I draw on sociocultural perspectives of learning to analyze three cases where teachers integrated CS into school science, one third grade, one fourth grade, and one high school Marine Biology classroom. Chapter 2 is a conceptual investigation of the opportunities for students to engage in scientific reasoning practices during CS data collection activities. Drawing on science education literature and vignettes from case studies, I argue that the teacher plays an important role in mediating opportunities for students to engage in investigative, explanatory, and argumentative practices of science through CS. Chapter 3 focuses on teacher framing of CS, how teachers perceive what is going on (Goffman, 1974) and how they communicate that to students as they launch CS tasks. Through analysis of videos and interviews of two upper elementary school teachers, I found that teachers frame CS for different purposes. These framings were influenced by teachers' goals, orientations towards science and CS, planning for instruction, and prior knowledge and experience. Chapter 4 examines how students demonstrate agency with environmental science as they explore their personal interests across their third grade classroom, school garden, and science lab contexts, through the lens of social practice theory (Holland, Lachicotte, Skinner, & Cain, 1998). Through analysis of classroom observations, student interviews, teacher interviews and important moments for three focal students, I found that student agency was enabled and constrained by the different cultures of the classroom, garden, and science lab. Despite affordances of the garden and science lab, the teachers' epistemic authority in the classroom permeated all three contexts, constraining student agency. In

  11. The thermal conductivity of mixed fuel U<sub>xPu>1-xsub>O>2sub>: molecular dynamics simulations

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiang-Yang [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Cooper, Michael William Donald [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Stanek, Christopher Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Andersson, Anders David Ragnar [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-10-16

    Mixed oxides (MOX), in the context of nuclear fuels, are a mixture of the oxides of heavy actinide elements such as uranium, plutonium and thorium. The interest in the UO<sub>2sub>-PuO>2sub> system arises from the fact that these oxides are used both in fast breeder reactors (FBRs) as well as in pressurized water reactors (PWRs). The thermal conductivity of UO<sub>2sub> fuel is an important material property that affects fuel performance since it is the key parameter determining the temperature distribution in the fuel, thus governing, e.g., dimensional changes due to thermal expansion, fission gas release rates, etc. For this reason it is important to understand the thermal conductivity of MOX fuel and how it differs from UO<sub>2sub>. Here, molecular dynamics (MD) simulations are carried out to determine quantitatively, the effect of mixing on the thermal conductivity of U<sub>xPu>1-xsub>O>2sub>, as a function of PuO<sub>2sub> concentrations, for a range of temperatures, 300 – 1500 K. The results will be used to develop enhanced continuum thermal conductivity models for MARMOT and BISON by INL. These models express the thermal conductivity as a function of microstructure state-variables, thus enabling thermal conductivity models with closer connection to the physical state of the fuel.

  12. The development and psychometric testing of a theory-based instrument to evaluate nurses' perception of clinical reasoning competence.

    Science.gov (United States)

    Liou, Shwu-Ru; Liu, Hsiu-Chen; Tsai, Hsiu-Min; Tsai, Ying-Huang; Lin, Yu-Ching; Chang, Chia-Hao; Cheng, Ching-Yu

    2016-03-01

    The purpose of the study was to develop and psychometrically test the Nurses Clinical Reasoning Scale. Clinical reasoning is an essential skill for providing safe and quality patient care. Identifying pre-graduates' and nurses' needs and designing training courses to improve their clinical reasoning competence becomes a critical task. However, there is no instrument focusing on clinical reasoning in the nursing profession. Cross-sectional design was used. This study included the development of the scale, a pilot study that preliminary tested the readability and reliability of the developed scale and a main study that implemented and tested the psychometric properties of the developed scale. The Nurses Clinical Reasoning Scale was developed based on the Clinical Reasoning Model. The scale includes 15 items using a Likert five-point scale. Data were collected from 2013-2014. Two hundred and fifty-one participants comprising clinical nurses and nursing pre-graduates completed and returned the questionnaires in the main study. The instrument was tested for internal consistency and test-retest reliability. Its validity was tested with content, construct and known-groups validity. One factor emerged from the factor analysis. The known-groups validity was confirmed. The Cronbach's alpha for the entire instrument was 0·9. The reliability and validity of the Nurses Clinical Reasoning Scale were supported. The scale is a useful tool and can be easily administered for the self-assessment of clinical reasoning competence of clinical nurses and future baccalaureate nursing graduates. Study limitations and further recommendations are discussed. © 2015 John Wiley & Sons Ltd.

  13. Testing Augmented Reality Systems for Spotting Sub-Surface Impurities

    DEFF Research Database (Denmark)

    Hald, Kasper; Rehm, Matthias; Moeslund, Thomas B.

    2018-01-01

    This paper describes setup and procedure for testing augmented reality systems for showing sub-surface positions of foreign elements in an opaque mass. The goal is it test four types of setup in terms of user accuracy and speed, the four setups being a head-mounted see-through display, an arm...

  14. Predictions of NO{sub x} formation in an NH{sub 3}-doped syngas flame using CFD combined with a detailed reaction mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Brink, A; Norstroem, T; Kilpinen, P; Hupa, M [Aabo Akademi, Turku (Finland). Combustion Chemistry Research Group

    1998-12-31

    The formation of NO{sub x} in a CO/H{sub 2}/CH{sub 4}/NH{sub 3} jet in a co-flowing air stream was modeled by use of CFD combined with a comprehensive detailed reaction mechanism. The comprehensive mechanism involved 340 reversible elementary reactions between 55 species. Three different approaches to include the detailed reaction mechanism were tested. In approach I, all chemistry was described with the comprehensive mechanism. In approaches IIa and IIb the comprehensive mechanism was used in post-processing calculations of the nitrogen chemistry. In approach IIa, the temperatures of the reacting structures obtained in the main calculations were used, whereas in approach IIb, the inlet temperatures to the reacting structures were taken from the main calculation. In approach IIIa and IIIb, empirical reaction mechanisms describing the nitrogen chemistry were tested. The turbulence-chemistry interaction was accounted for with a new model, which combines the Eddy-Dissipation Concept with a model based on the `Exchange by Interaction with the Mean`. There was a clear difference between the computed results and the measured ones. The use of approach I resulted in an obvious overprediction of the lift-off height. The predicted molar NO{sub x} yield with the approaches IIa and IIb were 89 % and 85 %, respectively, whereas a yield of 23 % had been measured. With the empirical mechanisms used in approach IIIa, a similar NO{sub x} yield was predicted as with approaches IIa and IIb. With IIIb the predicted NO{sub x} yield was 40 %. However, in this case 67 % of the NH{sub 3} remained unreacted. The reason for the large difference between the calculated NO{sub x} yield and the measured one reported in the literature is a poor modeling of the initial part of the fuel jet. A possible reason for this is the coarse grid. (author) 15 refs.

  15. Predictions of NO{sub x} formation in an NH{sub 3}-doped syngas flame using CFD combined with a detailed reaction mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Brink, A.; Norstroem, T.; Kilpinen, P.; Hupa, M. [Aabo Akademi, Turku (Finland). Combustion Chemistry Research Group

    1997-12-31

    The formation of NO{sub x} in a CO/H{sub 2}/CH{sub 4}/NH{sub 3} jet in a co-flowing air stream was modeled by use of CFD combined with a comprehensive detailed reaction mechanism. The comprehensive mechanism involved 340 reversible elementary reactions between 55 species. Three different approaches to include the detailed reaction mechanism were tested. In approach I, all chemistry was described with the comprehensive mechanism. In approaches IIa and IIb the comprehensive mechanism was used in post-processing calculations of the nitrogen chemistry. In approach IIa, the temperatures of the reacting structures obtained in the main calculations were used, whereas in approach IIb, the inlet temperatures to the reacting structures were taken from the main calculation. In approach IIIa and IIIb, empirical reaction mechanisms describing the nitrogen chemistry were tested. The turbulence-chemistry interaction was accounted for with a new model, which combines the Eddy-Dissipation Concept with a model based on the `Exchange by Interaction with the Mean`. There was a clear difference between the computed results and the measured ones. The use of approach I resulted in an obvious overprediction of the lift-off height. The predicted molar NO{sub x} yield with the approaches IIa and IIb were 89 % and 85 %, respectively, whereas a yield of 23 % had been measured. With the empirical mechanisms used in approach IIIa, a similar NO{sub x} yield was predicted as with approaches IIa and IIb. With IIIb the predicted NO{sub x} yield was 40 %. However, in this case 67 % of the NH{sub 3} remained unreacted. The reason for the large difference between the calculated NO{sub x} yield and the measured one reported in the literature is a poor modeling of the initial part of the fuel jet. A possible reason for this is the coarse grid. (author) 15 refs.

  16. Causal reasoning in physics

    CERN Document Server

    Frisch, Mathias

    2014-01-01

    Much has been written on the role of causal notions and causal reasoning in the so-called 'special sciences' and in common sense. But does causal reasoning also play a role in physics? Mathias Frisch argues that, contrary to what influential philosophical arguments purport to show, the answer is yes. Time-asymmetric causal structures are as integral a part of the representational toolkit of physics as a theory's dynamical equations. Frisch develops his argument partly through a critique of anti-causal arguments and partly through a detailed examination of actual examples of causal notions in physics, including causal principles invoked in linear response theory and in representations of radiation phenomena. Offering a new perspective on the nature of scientific theories and causal reasoning, this book will be of interest to professional philosophers, graduate students, and anyone interested in the role of causal thinking in science.

  17. Language experience narratives and the role of autobiographical reasoning in becoming an urban science teacher

    Science.gov (United States)

    Rivera Maulucci, Maria S.

    2011-06-01

    One of the central challenges globalization and immigration present to education is how to construct school language policies, procedures, and curricula to support academic success of immigrant youth. This case-study compares and contrasts language experience narratives along Elena's developmental trajectory of becoming an urban science teacher. Elena reflects upon her early language experiences and her more recent experiences as a preservice science teacher in elementary dual language classrooms. The findings from Elena's early schooling experiences provide an analysis of the linkages between Elena's developing English proficiency, her Spanish proficiency, and her autobiographical reasoning. Elena's experiences as a preservice teacher in two elementary dual language classrooms indicates ways in which those experiences helped to reframe her views about the intersections between language learning and science learning. I propose the language experience narrative, as a subset of the life story, as a way to understand how preservice teachers reconstruct past language experiences, connect to the present, and anticipate future language practices.

  18. Integrated dry NO{sub x}/SO{sub 2} emissions control system sodium-based dry sorbent injection test report. Test period: August 4, 1993--July 29, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R.A.; Shimoto, G.H.; Muzio, L.J. [Fossil Energy Research Corp., Laguna Hills, CA (United States); Hunt, T. [Public Service Co. of Colorado, Denver, CO (United States)

    1997-04-01

    The project goal is to demonstrate up to 70% reductions in NOx and SO{sub 2} emissions through the integration of: (1) down-fired low-NOx burners with overfire air; (2) Selective Non-Catalytic Reduction (SNCR) for additional NOx removal; and (3) dry sorbent injection and duct humidification for SO{sub 2} removal. This report documents the sixth phase of the test program, where the performance of dry sorbent injection with sodium compounds was evaluated as a SO{sub 2} removal technique. Dry sorbent injection was performed in-duct downstream of the air heater (ahead of the fabric filter), as well as at a higher temperature location between the economizer and air heater. Two sodium compounds were evaluated during this phase of testing: sodium sesquicarbonate and sodium bicarbonate. In-duct sodium injection with low levels of humidification was also investigated. This sixth test phase was primarily focused on a parametric investigation of sorbent type and feed rate, although boiler load and sorbent preparation parameters were also varied.

  19. Reasons and resources for being explicit about the practices of science

    Science.gov (United States)

    Egger, A. E.

    2015-12-01

    The Next Generation Science Standards (NGSS) promote a fundamental shift in the way science is taught. The new focus is on three-dimensional learning, which brings science and engineering practices together with disciplinary core ideas and cross-cutting concepts. A key component is performance expectations rather than bullet lists of content that students should know. One of the stated goals is that "all students should have sufficient knowledge of science and engineering to engage in public discussions on related issues." While the NGSS were developed for K-12, college instructors benefit from familiarity with them in two critical ways: first, they provide a research-based and clearly articulated approach to three-dimensional learning that applies across the grade spectrum, and second, future K-12 teachers are sitting in their college-level science courses, and awareness of the skills those future teachers need can help direct course design. More specifically, while most college-level science courses make use of the science and engineering practices described in the NGSS, few offer explicit instruction in them or how they intertwine with disciplinary core ideas and cross-cutting concepts. Yet this explicit instruction is critical to building scientific literacy in future teachers—and all students. Many textbooks and laboratory courses limit a discussion of the process of science to one chapter or exercise, and expect students to be able to apply those concepts. In contrast, new resources from Visionlearning (http://www.visionlearning.com), InTeGrate (http://serc.carleton.edu/integrate), and other projects hosted at the Science Education Resource Center (http://serc.carleton.edu) were developed with explicit and pervasive integration of the nature and practices of science in mind. These freely available, classroom-tested and reviewed resources support instructors in introductory/general education courses as well as teacher preparation and more advanced courses.

  20. The Application of the Theory of Reasoned Action and Planned Behavior to Prevention Science in Counseling Psychology

    Science.gov (United States)

    Romano, John L.; Netland, Jason D.

    2008-01-01

    The theory of reasoned action and planned behavior (TRA/PB) is a model of behavior change that has been extensively studied in the health sciences but has had limited exposure in the counseling psychology literature. The model offers counseling psychologists a framework to conceptualize prevention research and practice. The model is important to…

  1. The CEA JOSEFA test facility for sub-size conductors and joints

    International Nuclear Information System (INIS)

    Decool, P.; Libeyre, P.; Van Houtte, D.; Ciazynski, D.; Zani, L.; Serries, J.P.; Cloez, H.; Bej, S.

    2003-01-01

    The JOSEFA (Joint Sub-size Experiment FAcility) experimental test facility, installed at CEA/Cadarache is devoted to perform tests at cryogenic temperature on sub-size superconducting conductor and joint samples under parallel or transverse magnetic field. This facility was built in 1993 to investigate the performances of joints of cable-in-conduit conductors at sub-size level and further upgraded in the framework of European tasks. The samples of hairpin type using sub-size ITER conductors are cooled by a circulation of supercritical helium in a temperature range from 5 to 15 K and tested at a maximum current up to 10 kA. Two different helium bath cooled magnets allow to apply DC or AC transverse magnetic field up to 3.5 T or longitudinal magnetic field up to 7.5 T. A sliding system with a 240 mm stroke on the sample cryostat allows to test separately in the same sample either the conductor or the joint performances. The paper reports on how, through the conductor and joint development tasks, the facility performances were successfully increased and tested. The ITER TFMC joints using Nb3Sn conductors were first developed on this facility. The last developments, performed on ITER PF NbTi conductors and joints proved this facility to be a versatile and useful tool for superconducting magnet developments and showed the interest of possible upgrading to finalize conductor design. (author)

  2. Verification of causal influences of reasoning skills and epistemology on physics conceptual learning

    Directory of Open Access Journals (Sweden)

    Lin Ding

    2014-07-01

    Full Text Available This study seeks to test the causal influences of reasoning skills and epistemologies on student conceptual learning in physics. A causal model, integrating multiple variables that were investigated separately in the prior literature, is proposed and tested through path analysis. These variables include student preinstructional reasoning skills measured by the Classroom Test of Scientific Reasoning, pre- and postepistemological views measured by the Colorado Learning Attitudes about Science Survey, and pre- and postperformance on Newtonian concepts measured by the Force Concept Inventory. Students from a traditionally taught calculus-based introductory mechanics course at a research university participated in the study. Results largely support the postulated causal model and reveal strong influences of reasoning skills and preinstructional epistemology on student conceptual learning gains. Interestingly enough, postinstructional epistemology does not appear to have a significant influence on student learning gains. Moreover, pre- and postinstructional epistemology, although barely different from each other on average, have little causal connection between them.

  3. Multilayered samples reconstructed by measuring K{sub α}/K{sub β} or L{sub α}/L{sub β} X-ray intensity ratios by EDXRF

    Energy Technology Data Exchange (ETDEWEB)

    Cesareo, Roberto, E-mail: cesareo@uniss.it [Istituto per lo Studio dei Materiali Nano Strutturati, CNR-Montelibretti, via Salaria km. 29.5, 00015 Monterotondo (Romania); Assis, Joaquim T. de, E-mail: joaquim.iprj@gmail.com [Universidade do Estado do Rio de Janeiro, Instituto Politécnico, P.O. Box 97282, 28625-570 Nova Friburgo, RJ (Brazil); Roldán, Clodoaldo, E-mail: Clodoaldo.Roldan@uv.es [Instituto de Ciencia de los Materiales, Universidad de Valencia, P.O. Box 22085, E46071 Valencia (Spain); Bustamante, Angel D., E-mail: angelbd1@gmail.com [Universidad Nacional Mayor de San Marcos, Lima (Peru); Brunetti, Antonio, E-mail: brunetti@uniss.it [Dipartimento di Scienze Politiche, Scienza della Comunicazione e Ingegneria dell’ Informazione, Università di Sassari, Sassari (Italy); Schiavon, Nick [Hercules Laboratory and Évora Geophysical Centre, University of Evora (Portugal)

    2013-10-01

    In this paper a general method based on energy-dispersive X-ray fluorescence (EDXRF) analysis has been tested to assess its possible use as a tool to reconstruct the structure and determine the thickness of two and/or multi-layered materials. The method utilizes the X-ray intensity ratios of K{sub α}/K{sub β} or L{sub α}/L{sub β} peaks (or the ratio of these peaks) for selected elements present in multi-layered objects of various materials (Au alloys, gilded Cu, gilded Ag, gilded Pb, Ag–Au Tumbaga, stone surfaces with protective treatments, Zn or Nickel plating on metals). Results show that, in the case of multi-layered samples, a correct calculation of the peak ratio (K{sub α} /K{sub β} and/or L{sub α}/L{sub β}) of relevant elements from energy-dispersive X-ray fluorescence spectra, can provide important information in assessing the exact location of each layer and for calculating its thickness. The methodological approach shown may have important applications not only in materials science but also when dealing with the conservation and restoration of multi-layered cultural heritage objects where the use of a Non-Destructive techniques to determine slight chemical and thickness variations in the layered structure is often of paramount importance to achieve the best results.

  4. Quantitative Reasoning in Environmental Science: Rasch Measurement to Support QR Assessment

    Directory of Open Access Journals (Sweden)

    Robert L. Mayes

    2015-07-01

    Full Text Available The ability of middle and high school students to reason quantitatively within the context of environmental science was investigated. A quantitative reasoning (QR learning progression, with associated QR assessments in the content areas of biodiversity, water, and carbon, was developed based on three QR progress variables: quantification act, quantitative interpretation, and quantitative modeling. Diagnostic instruments were developed specifically for the progress variable quantitative interpretation (QI, each consisting of 96 Likert-scale items. Each content version of the instrument focused on three scale levels (macro scale, micro scale, and landscape scale and four elements of QI identified in prior research (trend, translation, prediction, and revision. The QI assessments were completed by 362, 6th to 12th grade students in three U.S. states. Rasch (1960/1980 measurement was used to determine item and person measures for the QI instruments, both to examine validity and reliability characteristics of the instrument administration and inform the evolution of the learning progression. Rasch methods allowed identification of several QI instrument revisions, including modification of specific items, reducing number of items to avoid cognitive fatigue, reconsidering proposed item difficulty levels, and reducing Likert scale to 4 levels. Rasch diagnostics also indicated favorable levels of instrument reliability and appropriate targeting of item abilities to student abilities for the majority of participants. A revised QI instrument is available for STEM researchers and educators.

  5. Middle School Students' Use of Epistemological Resources while Reasoning about Science Performance Tasks and Media Reports of Socioscientific Issues

    Science.gov (United States)

    Buckingham, Brandy L. E.

    The goal of science education is to prepare students to make decisions about the complicated socioscientific issues that are an inescapable part of modern life, from personal medical decisions to evaluating a political candidate's environmental platform. We cannot expect adults to maintain a deep conceptual understanding of the current state of every branch of science that might prove relevant to their lives, so we must prepare them to rely on other knowledge to make these decisions. Epistemological beliefs about scientific knowledge--what it is, its purpose, how it is constructed--are one type of knowledge that could be brought to bear when evaluating scientific claims. Complicating this situation is the fact that most adults will get most of their information about these socioscientific issues from the news media. Journalists do not have the same goals or norms as scientists, and this media lens can distort scientific issues. This dissertation addresses the question of whether we can assess epistemological change in a way that gives us meaningful information about how people will apply their epistemological understanding of science when they make decisions in the real world. First, I designed a written assessment made up of performance tasks to assess middle school students' implicit epistemological beliefs, and looked at whether we can use such an assessment to see epistemological change over two years. I then gave the same students news articles about whether there is a link between vaccines and autism and looked at their reasoning about this issue and how the journalistic features of two different articles impacted their reasoning. Finally, I examined the external validity of the epistemology assessment by looking at whether it predicted anything about students' responses to the news articles. While I was able to find evidence of differences between eighth graders' and sixth graders' use of epistemological resources within the performance tasks, I found that

  6. UO{sub 2} and PuO{sub 2} utilization in high temperature engineering test reactor with helium coolant

    Energy Technology Data Exchange (ETDEWEB)

    Waris, Abdul, E-mail: awaris@fi.itb.ac.id; Novitrian,; Pramuditya, Syeilendra; Su’ud, Zaki [Nuclear Physics and Biophysics Research Division, Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung (Indonesia); Aji, Indarta K. [Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung (Indonesia)

    2016-03-11

    High temperature engineering test reactor (HTTR) is one of high temperature gas cooled reactor (HTGR) types which has been developed by Japanese Atomic Energy Research Institute (JAERI). The HTTR is a graphite moderator, helium gas coolant, 30 MW thermal output and 950 °C outlet coolant temperature for high temperature test operation. Original HTTR uses UO{sub 2} fuel. In this study, we have evaluated the use of UO{sub 2} and PuO{sub 2} in form of mixed oxide (MOX) fuel in HTTR. The reactor cell calculation was performed by using SRAC 2002 code, with nuclear data library was derived from JENDL3.2. The result shows that HTTR can obtain its criticality condition if the enrichment of {sup 235}U in loaded fuel is 18.0% or above.

  7. Testing of TAMU3: a Nb<sub>3sub>Sn Block–Coil Dipole with Stress Management

    Energy Technology Data Exchange (ETDEWEB)

    McIntyre, Peter [Texas A & M Univ., College Station, TX (United States)

    2015-09-20

    The Accelerator Research Lab (ARL) at Texas A&M has recently concluded the construction and testing of a superconducting block-coil dipole TAMU3. TAMU3 reached 85% of the resistive-onset short sample critical current (0.1 μV/cm criterion) that was measured on extracted strands at the National High Magnetic Field Lab. Peak magnet current was 6603 amps, and all with quenches originated in the vicinity of the hard-way chicane near the exit lead of the TAMU3c inner winding. Leading up to the testing we discovered that we had made two grievous mistakes in the fabrication (we mistakenly used the wrong superconducting wire for the cables of the inner windings) and the heat treatment (we used a heat treatment that was too hot and too long). We extracted strands from the leads of the inner and outer windings, and colleagues at NHMFL performed short-sample measurements upon them. The NHMFL measurements indicated RRR ~ 2-5, which gives very little stability against microquenches. The short-sample tests of the extracted strands exhibited a long resistive transition, in which there was a current I<sub>sc>(B) beyond which it became resistive, then a higher current In(B) at which it went fully normal. Using the I<sub>sc>(B) data we predicted a short-sample limit for the revised load line of TAMU3 of 7700 A (9 T) – a disappointing reduction from the 14 T objective. On those unhappy notes we undertook the testing of the dipole. The first quench occurred at 5695 A, and the dipole trained thereafter to a maximum quench current of 6600 A (7.6 T), 85% of the compromised short-sample limit. All quenches occurred at a single location, in the region of the S-bend transition and outer lead of one inner winding. Data was collected from stress transducers on the outer windings to evaluate stress management, and on the coil ends to evaluate capture of axial forces by staticfriction lock. The low field reached prevented us from extending those tests to the stress levels where they

  8. The effects of students' reasoning abilities on conceptual understandings and problem-solving skills in introductory mechanics

    International Nuclear Information System (INIS)

    Ates, S; Cataloglu, E

    2007-01-01

    The purpose of this study was to determine if there are relationships among freshmen/first year students' reasoning abilities, conceptual understandings and problem-solving skills in introductory mechanics. The sample consisted of 165 freshmen science education prospective teachers (female = 86, male = 79; age range 17-21) who were enrolled in an introductory physics course. Data collection was done during the fall semesters in two successive years. At the beginning of each semester, the force concept inventory (FCI) and the classroom test of scientific reasoning (CTSR) were administered to assess students' initial understanding of basic concepts in mechanics and reasoning levels. After completing the course, the FCI and the mechanics baseline test (MBT) were administered. The results indicated that there was a significant difference in problem-solving skill test mean scores, as measured by the MBT, among concrete, formal and postformal reasoners. There were no significant differences in conceptual understanding levels of pre- and post-test mean scores, as measured by FCI, among the groups. The Benferroni post hoc comparison test revealed which set of reasoning levels showed significant difference for the MBT scores. No statistical difference between formal and postformal reasoners' mean scores was observed, while the mean scores between concrete and formal reasoners and concrete and postformal reasoners were statistically significantly different

  9. Perception of Risk and Terrorism-Related Behavior Change: Dual Influences of Probabilistic Reasoning and Reality Testing

    Science.gov (United States)

    Denovan, Andrew; Dagnall, Neil; Drinkwater, Kenneth; Parker, Andrew; Clough, Peter

    2017-01-01

    The present study assessed the degree to which probabilistic reasoning performance and thinking style influenced perception of risk and self-reported levels of terrorism-related behavior change. A sample of 263 respondents, recruited via convenience sampling, completed a series of measures comprising probabilistic reasoning tasks (perception of randomness, base rate, probability, and conjunction fallacy), the Reality Testing subscale of the Inventory of Personality Organization (IPO-RT), the Domain-Specific Risk-Taking Scale, and a terrorism-related behavior change scale. Structural equation modeling examined three progressive models. Firstly, the Independence Model assumed that probabilistic reasoning, perception of risk and reality testing independently predicted terrorism-related behavior change. Secondly, the Mediation Model supposed that probabilistic reasoning and reality testing correlated, and indirectly predicted terrorism-related behavior change through perception of risk. Lastly, the Dual-Influence Model proposed that probabilistic reasoning indirectly predicted terrorism-related behavior change via perception of risk, independent of reality testing. Results indicated that performance on probabilistic reasoning tasks most strongly predicted perception of risk, and preference for an intuitive thinking style (measured by the IPO-RT) best explained terrorism-related behavior change. The combination of perception of risk with probabilistic reasoning ability in the Dual-Influence Model enhanced the predictive power of the analytical-rational route, with conjunction fallacy having a significant indirect effect on terrorism-related behavior change via perception of risk. The Dual-Influence Model possessed superior fit and reported similar predictive relations between intuitive-experiential and analytical-rational routes and terrorism-related behavior change. The discussion critically examines these findings in relation to dual-processing frameworks. This

  10. Perception of Risk and Terrorism-Related Behavior Change: Dual Influences of Probabilistic Reasoning and Reality Testing.

    Science.gov (United States)

    Denovan, Andrew; Dagnall, Neil; Drinkwater, Kenneth; Parker, Andrew; Clough, Peter

    2017-01-01

    The present study assessed the degree to which probabilistic reasoning performance and thinking style influenced perception of risk and self-reported levels of terrorism-related behavior change. A sample of 263 respondents, recruited via convenience sampling, completed a series of measures comprising probabilistic reasoning tasks (perception of randomness, base rate, probability, and conjunction fallacy), the Reality Testing subscale of the Inventory of Personality Organization (IPO-RT), the Domain-Specific Risk-Taking Scale, and a terrorism-related behavior change scale. Structural equation modeling examined three progressive models. Firstly, the Independence Model assumed that probabilistic reasoning, perception of risk and reality testing independently predicted terrorism-related behavior change. Secondly, the Mediation Model supposed that probabilistic reasoning and reality testing correlated, and indirectly predicted terrorism-related behavior change through perception of risk. Lastly, the Dual-Influence Model proposed that probabilistic reasoning indirectly predicted terrorism-related behavior change via perception of risk, independent of reality testing. Results indicated that performance on probabilistic reasoning tasks most strongly predicted perception of risk, and preference for an intuitive thinking style (measured by the IPO-RT) best explained terrorism-related behavior change. The combination of perception of risk with probabilistic reasoning ability in the Dual-Influence Model enhanced the predictive power of the analytical-rational route, with conjunction fallacy having a significant indirect effect on terrorism-related behavior change via perception of risk. The Dual-Influence Model possessed superior fit and reported similar predictive relations between intuitive-experiential and analytical-rational routes and terrorism-related behavior change. The discussion critically examines these findings in relation to dual-processing frameworks. This

  11. Perception of Risk and Terrorism-Related Behavior Change: Dual Influences of Probabilistic Reasoning and Reality Testing

    Directory of Open Access Journals (Sweden)

    Andrew Denovan

    2017-10-01

    Full Text Available The present study assessed the degree to which probabilistic reasoning performance and thinking style influenced perception of risk and self-reported levels of terrorism-related behavior change. A sample of 263 respondents, recruited via convenience sampling, completed a series of measures comprising probabilistic reasoning tasks (perception of randomness, base rate, probability, and conjunction fallacy, the Reality Testing subscale of the Inventory of Personality Organization (IPO-RT, the Domain-Specific Risk-Taking Scale, and a terrorism-related behavior change scale. Structural equation modeling examined three progressive models. Firstly, the Independence Model assumed that probabilistic reasoning, perception of risk and reality testing independently predicted terrorism-related behavior change. Secondly, the Mediation Model supposed that probabilistic reasoning and reality testing correlated, and indirectly predicted terrorism-related behavior change through perception of risk. Lastly, the Dual-Influence Model proposed that probabilistic reasoning indirectly predicted terrorism-related behavior change via perception of risk, independent of reality testing. Results indicated that performance on probabilistic reasoning tasks most strongly predicted perception of risk, and preference for an intuitive thinking style (measured by the IPO-RT best explained terrorism-related behavior change. The combination of perception of risk with probabilistic reasoning ability in the Dual-Influence Model enhanced the predictive power of the analytical-rational route, with conjunction fallacy having a significant indirect effect on terrorism-related behavior change via perception of risk. The Dual-Influence Model possessed superior fit and reported similar predictive relations between intuitive-experiential and analytical-rational routes and terrorism-related behavior change. The discussion critically examines these findings in relation to dual

  12. Testing of one-inch UF{sub 6} cylinder valves under simulated fire conditions

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, P.G. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

    1991-12-31

    Accurate computational models which predict the behavior of UF{sub 6} cylinders exposed to fires are required to validate existing firefighting and emergency response procedures. Since the cylinder valve is a factor in the containment provided by the UF{sub 6} cylinder, its behavior under fire conditions has been a necessary assumption in the development of such models. Consequently, test data is needed to substantiate these assumptions. Several studies cited in this document provide data related to the behavior of a 1-inch UF{sub 6} cylinder valve in fire situations. To acquire additional data, a series of tests were conducted at the Paducah Gaseous Diffusion Plant (PGDP) under a unique set of test conditions. This document describes this testing and the resulting data.

  13. Supporting Mechanistic Reasoning in Domain-Specific Contexts

    Science.gov (United States)

    Weinberg, Paul J.

    2017-01-01

    Mechanistic reasoning is an epistemic practice central within science, technology, engineering, and mathematics disciplines. Although there has been some work on mechanistic reasoning in the research literature and standards documents, much of this work targets domain-general characterizations of mechanistic reasoning; this study provides…

  14. N{sub 2}O and CH{sub 4} Emission from Wastewater Collection and Treatment Systems (GWRC). State of the Science Report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-11-15

    The Global Water Research Coalition (GWRC) is an international organisation that is dedicated to the exchange and generation of knowledge to support sustainable development and management of the urban water cycle. The research agenda is developed by the member organisations of the GWRC and reflects their priorities and recognises global trends and drivers that affect the urban water cycle. The present research agenda includes Climate Change as one of the priorities areas. This research area comprises topics related to the possible impact of climate change on the urban water sector as well as the possible contribution to climate change by the urban water sector via the direct and indirect emission of greenhouse gasses (GHG). The objective of this joint effort was to collect and develop knowledge needed to understand and manage the emission of N{sub 2}O (nitrous oxide) and CH{sub 4} (methane) by wastewater collection and treatment systems. Starting with a kick-off meeting in Vienna in September 2008, the GWRC members involved in this activity have bundled their individual research programs on this topic, aligned methodologies used and exchanged and discussed the resulting information of the programs and developed additional actions where needed. The outcomes were reviewed and discussed at a final workshop in Montreal in September 2010. These activities have resulted in two reports: this State of the Science report which presents an overview of the current knowledge and know-how regarding the emissions of N{sub 2}O and CH{sub 4} by wastewater collection and treatment systems and a Technical Report which includes all the details, facts and figures of the underlying studies used to develop the State of the Science report. For the Technical Report a separate record has been prepared.

  15. Public policy, rationality and reason

    Directory of Open Access Journals (Sweden)

    Rodolfo Canto Sáenz

    2015-07-01

    Full Text Available This work suggests the incorporation of practical reason in the design, implementation and evaluation of public policies, alongside instrumental rationality. It takes two proposals that today point in this direction: Rawls distinction between reasonable (practical reason and rational (instrumental reason and what this author calls the CI Procedure (categorical imperative procedure and Habermas model of deliberative democracy. The main conclusion is that the analysis of public policies can not be limited to rather narrow limits of science, but requires the contribution of political and moral philosophy.

  16. Insights From the Defining Issues Test on Moral Reasoning Competencies Development in Community Pharmacists.

    Science.gov (United States)

    Roche, Cicely; Thoma, Steve

    2017-10-01

    Objective. To investigate whether a profession-specific educational intervention affected the development of moral reasoning competencies in community pharmacists, as measured by the Defining Issues Test (DIT2). Methods. This research used a repeated measures pre-post educational intervention design as a quasi-randomized, controlled, crossover study to evaluate changes in the moral reasoning scores of 27 volunteer community pharmacists in Ireland. Results. Changes in pharmacists' moral reasoning competencies development, as reported by P-Scores and N2-Scores, were found to be significant. In addition, interaction effects were observed between developmental scores on the DIT2 and whether participants were determined to be consolidated in their reasoning pre- and post-engagement with the educational intervention. Conclusion. Short profession-specific educational interventions have the potential to positively affect the development of moral reasoning competencies of community pharmacists.

  17. Preliminary Test of Friction disk type turbine for S-CO{sub 2} cycle application

    Energy Technology Data Exchange (ETDEWEB)

    Baik, Seungjoon; Kim, Hyeon Tae; Lee, Jeong Ik [KAIST, Daejeon (Korea, Republic of)

    2016-05-15

    Due to the relatively mild sodium-CO{sub 2} interaction, the S-CO{sub 2} Brayton cycle can reduce the accident consequence compared to the steam Rankine cycle. Also the S-CO{sub 2} power conversion cycle can achieve high efficiency for SFR core thermal condition. Moreover, the S-CO{sub 2} power cycle can reduce the total cycle footprint due to high density of the working fluid. However, the high pressure operating condition and low viscosity of the fluid cause difficulties in designing appropriate seals and multi-stage turbo machineries. To solve the problem for designing turbo machineries in a creative way, KAIST research team tested a friction disk type turbine concept for the S-CO{sub 2} cycle application. In this paper, the investigation of the Tesla turbine and preliminary test results with compressed air are covered. The KAIST research team investigated a friction disk type turbine, named as Tesla turbine, for the S-CO{sub 2} power cycle applications. Due to the robust design of the fiction disk type, the Tesla turbine technology can be utilized not only for S-CO{sub 2} turbo machinery but also for the multi-phase or sludge flow turbo machinery. The preliminary test of lab-scale Tesla turbine with compressed air was conducted. The high pressure vessel was manufactured for the S-CO{sub 2} operating condition. The test will be concentrated on the turbine efficiency measurement under various conditions and development of the design methodology.

  18. The concept verification testing of materials science payloads

    Science.gov (United States)

    Griner, C. S.; Johnston, M. H.; Whitaker, A.

    1976-01-01

    The concept Verification Testing (CVT) project at the Marshall Space Flight Center, Alabama, is a developmental activity that supports Shuttle Payload Projects such as Spacelab. It provides an operational 1-g environment for testing NASA and other agency experiment and support systems concepts that may be used in shuttle. A dedicated Materials Science Payload was tested in the General Purpose Laboratory to assess the requirements of a space processing payload on a Spacelab type facility. Physical and functional integration of the experiments into the facility was studied, and the impact of the experiments on the facility (and vice versa) was evaluated. A follow-up test designated CVT Test IVA was also held. The purpose of this test was to repeat Test IV experiments with a crew composed of selected and trained scientists. These personnel were not required to have prior knowledge of the materials science disciplines, but were required to have a basic knowledge of science and the scientific method.

  19. Theoretical and practical significance of formal reasoning

    Science.gov (United States)

    Linn, Marcia C.

    Piaget's theory has profoundly influenced science education research. Following Piaget, researchers have focused on content-free strategies, developmentally based mechanisms, and structural models of each stage of reasoning. In practice, factors besides those considered in Piaget's theory influence whether or not a theoretically available strategy is used. Piaget's focus has minimized the research attention placed on what could be called practical factors in reasoning. Practical factors are factors that influence application of a theoretically available strategy, for example, previous experience with the task content, familiarity with task instructions, or personality style of the student. Piagetian theory has minimized the importance of practical factors and discouraged investigation of (1) the role of factual knowledge in reasoning, (2) the diagnosis of specific, task-based errors in reasoning, (3) the influence of individual aptitudes on reasoning (e.g., field dependence-independence), and (4) the effect of educational interventions designed to change reasoning. This article calls for new emphasis on practical factors in reasoning and suggests why research on practical factors in reasoning will enhance our understanding of how scientific reasoning is acquired and of how science education programs can foster it.

  20. Use of low enriched /sup 15/N/sub 2/ for symbiotic fixation tests

    Energy Technology Data Exchange (ETDEWEB)

    Victoria, R L

    1975-01-01

    Gaseous atmospheres containing /sup 15/N/sub 2/ with low enrichment were used to test symbiotic nitrogen fixation in beans (Phaseolus vulgari, L.). The tests of fixation in nodulated roots and the tests of fixation in the whole plant, in which the plants were placed inside a specially constructed growth chamber, gave positive results and suggest that the methodology used can be very helpfull in more detailed studies on symbiotic fixation. Samples of atmospheric air were purified by absorption of O/sub 2/ and CO/sub 2/ by two methods. The purified N/sub 2/ obtained was analysed and the results were compared. Samples of bean plant material were collected in natural conditions and analysed for /sup 15/N natural variation. Several samples were prepared for /sup 15/N isotopic analysis by two methods. The results obtained were compared. All samples were analysed in an Atlas-Varian Ch-4 model mass spectrometer, and the results were given in delta /sup 15/N/sub 0///sup 00/ variation in relation to a standard gas.

  1. Evolutionary Science as a Method to Facilitate Higher Level Thinking and Reasoning in Medical Training.

    Science.gov (United States)

    Graves, Joseph L; Reiber, Chris; Thanukos, Anna; Hurtado, Magdalena; Wolpaw, Terry

    2016-10-15

    Evolutionary science is indispensable for understanding biological processes. Effective medical treatment must be anchored in sound biology. However, currently the insights available from evolutionary science are not adequately incorporated in either pre-medical or medical school curricula. To illuminate how evolution may be helpful in these areas, examples in which the insights of evolutionary science are already improving medical treatment and ways in which evolutionary reasoning can be practiced in the context of medicine are provided. In order to facilitate the learning of evolutionary principles, concepts derived from evolutionary science that medical students and professionals should understand are outlined. These concepts are designed to be authoritative and at the same time easily accessible for anyone with the general biological knowledge of a first-year medical student. Thus we conclude that medical practice informed by evolutionary principles will be more effective and lead to better patient outcomes.Furthermore, it is argued that evolutionary medicine complements general medical training because it provides an additional means by which medical students can practice the critical thinking skills that will be important in their future practice. We argue that core concepts from evolutionary science have the potential to improve critical thinking and facilitate more effective learning in medical training. © The Author(s) 2016. Published by Oxford University Press on behalf of the Foundation for Evolution, Medicine, and Public Health.

  2. Anion- or Cation-Exchange Membranes for NaBH<sub>4sub>/H>2sub>O>2 sub>Fuel Cells?

    Directory of Open Access Journals (Sweden)

    César A. C. Sequeira

    2012-07-01

    Full Text Available Direct borohydride fuel cells (DBFC, which operate on sodium borohydride (NaBH<sub>4sub> as the fuel, and hydrogen peroxide (H<sub>2sub>O>2sub> as the oxidant, are receiving increasing attention. This is due to their promising use as power sources for space and underwater applications, where air is not available and gas storage poses obvious problems. One key factor to improve the performance of DBFCs concerns the type of separator used. Both anion- and cation-exchange membranes may be considered as potential separators for DBFC. In the present paper, the effect of the membrane type on the performance of laboratory NaBH<sub>4sub>/H>2sub>O>2sub> fuel cells using Pt electrodes is studied at room temperature. Two commercial ion-exchange membranes from Membranes International Inc., an anion-exchange membrane (AMI-7001S and a cation-exchange membrane (CMI-7000S, are tested as ionic separators for the DBFC. The membranes are compared directly by the observation and analysis of the corresponding DBFC’s performance. Cell polarization, power density, stability, and durability tests are used in the membranes’ evaluation. Energy densities and specific capacities are estimated. Most tests conducted, clearly indicate a superior performance of the cation-exchange membranes over the anion-exchange membrane. The two membranes are also compared with several other previously tested commercial membranes. For long term cell operation, these membranes seem to outperform the stability of the benchmark Nafion membranes but further studies are still required to improve their instantaneous power load.

  3. Patterns of biomedical science production in a sub-Saharan research center

    Directory of Open Access Journals (Sweden)

    Agnandji Selidji T

    2012-03-01

    Full Text Available Abstract Background Research activities in sub-Saharan Africa may be limited to delegated tasks due to the strong control from Western collaborators, which could lead to scientific production of little value in terms of its impact on social and economic innovation in less developed areas. However, the current contexts of international biomedical research including the development of public-private partnerships and research institutions in Africa suggest that scientific activities are growing in sub-Saharan Africa. This study aims to describe the patterns of clinical research activities at a sub-Saharan biomedical research center. Methods In-depth interviews were conducted with a core group of researchers at the Medical Research Unit of the Albert Schweitzer Hospital from June 2009 to February 2010 in Lambaréné, Gabon. Scientific activities running at the MRU as well as the implementation of ethical and regulatory standards were covered by the interview sessions. Results The framework of clinical research includes transnational studies and research initiated locally. In transnational collaborations, a sub-Saharan research institution may be limited to producing confirmatory and late-stage data with little impact on economic and social innovation. However, ethical and regulatory guidelines are being implemented taking into consideration the local contexts. Similarly, the scientific content of studies designed by researchers at the MRU, if local needs are taken into account, may potentially contribute to a scientific production with long-term value on social and economic innovation in sub-Saharan Africa. Conclusion Further research questions and methods in social sciences should comprehensively address the construction of scientific content with the social, economic and cultural contexts surrounding research activities.

  4. Terrestrial analogs, planetary geology, and the nature of geological reasoning

    Science.gov (United States)

    Baker, Victor R.

    2014-05-01

    Analogical reasoning is critical to planetary geology, but its role can be misconstrued by those unfamiliar with the practice of that science. The methodological importance of analogy to geology lies in the formulation of genetic hypotheses, an absolutely essential component of geological reasoning that was either ignored or denigrated by most 20th century philosophers of science, who took the theoretical/ experimental methodology of physics to be the sole model for all of scientific inquiry. Following the seminal 19th century work of Grove Karl Gilbert, an early pioneer of planetary geology, it has long been recognized that broad experience with and understanding of terrestrial geological phenomena provide geologists with their most effective resource for the invention of potentially fruitful, working hypotheses. The actions of (1) forming such hypotheses, (2) following their consequences, and (3) testing those consequences comprise integral parts of effective geological practice in regard to the understanding of planetary surfaces. Nevertheless, the logical terminology and philosophical bases for such practice will be unfamiliar to most planetary scientists, both geologists and nongeologists. The invention of geological hypotheses involves both inductive inferences of the type Gilbert termed “empiric classification” and abductive inferences of a logical form made famous by the 19th century American logician Charles Sanders Peirce. The testing and corroboration of geological hypotheses relies less on the correspondence logic of theoretical/ experimental sciences, like physics, and more on the logic of consistency, coherence, and consilience that characterizes the investigative and historical sciences of interpretation exemplified by geology.

  5. Using Interactive eBooks To Educate Children About Sub-seafloor Science

    Science.gov (United States)

    Kurtz, K.

    2016-02-01

    Sub-seafloor scientific research has the power to spark the imaginations of elementary age children with its mysterious nature, cutting-edge research, and its connections to kid friendly science topics, such as volcanoes, the extinction of dinosaurs and the search for extraterrestrial life. These factors have been utilized to create two interactive eBooks for elementary students and teachers, integrating high quality science information, highly engaging and age-appropriate illustrations, and rhyming text. The first eBook introduces children to the research and discoveries of the JOIDES Resolution research vessel. The creators were able to build-on the knowledge gained in creating the first eBook to create a second eBook that focuses on the discoveries of microbial life in the sub-seafloor. The eBooks present information as traditional, linear, illustrated children's books, but the eBook format allows the book to be available online for free to anyone and allows teachers to project the book on a classroom screen so all students can easily see the illustrations. The iPad versions also provide an interactive, learner-led educational experience, where cognitively appropriate videos, photos and other forms of information can be accessed with the tap of a finger to answer reader questions and enrich their learning experience. These projects provide an example and model of the products that can result from high level and meaningful partnerships between scientists, educators, artists and writers.

  6. Design and research on the measurement platform of the effective thermal conductivity for Li{sub 4}SiO{sub 4} and Li{sub 2}TiO{sub 3} pebble bed

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yuanjie, E-mail: yuanjli@ustc.edu.cn; Yang, Wanli; Jin, Cheng; Zhao, Pinghui; Chen, Hongli

    2015-10-15

    China is carrying out the conceptual design of Chinese Fusion Engineering Testing Reactor (CFETR), and the Helium Cooled Pebble Bed (HCPB) blanket concept is one of the main choices for tritium production. Li{sub 4}SiO{sub 4} and Li{sub 2}TiO{sub 3} are the candidate breeder materials for the HCPB blanket concept. In the HCPB blanket, breeding pebbles with the diameter range of 0.6–1.2 mm are placed between two plates and the bed shall be cooled. Accordingly, effective thermal conductivity of pebble beds needs to be determined for the heat transfer calculation. Measurements of the heat transfer parameters of Li{sub 4}SiO{sub 4} and Li{sub 2}TiO{sub 3} pebble beds are being performed at the University of Science and Technology of China (USTC). Two measurement methods are being used. One is the steady state method with the use of thermocouples to measure the temperature distribution of the pebble bed. Another is transient thermal probe method using the temperature variation of the thermal probe and Monte Carlo inversion method to calculate the heat transfer parameters of the pebble bed. This paper will report on the progress of these measurement platforms.

  7. Surface Ocean CO<sub>2sub> Atlas (SOCAT) gridded data products

    Digital Repository Service at National Institute of Oceanography (India)

    Sabine, C.L.; Hankin, S.; Koyuk, H.; Bakker, D.C.E.; Pfeil, B.; Olsen, A; Metzl, N.; Kozyr, A; Fassbender, A; Manke, A; Malczyk, J.; Akl, J.; Alin, S.R.; Bellerby, R.G.J.; Borges, A; Boutin, J.; Brown, P.J.; Cai, W.-J.; Chavez, F.P.; Chen, A.; Cosca, C.; Feely, R.A.; Gonzalez-Davila, M.; Goyet, C.; Hardman-Mountford, N.; Heinze, C.; Hoppema, M.; Hunt, C.W.; Hydes, D.; Ishii, M.; Johannessen, T.; Key, R.M.; Kortzinger, A.; Landschutzer, P.; Lauvset, S.K.; Lefevre, N.; Lenton, A.; Lourantou, A.; Merlivat, L.; Midorikawa, T.; Mintrop, L.; Miyazaki, C.; Murata, A.; Nakadate, A.; Nakano, Y.; Nakaoka, S.; Nojiri, Y.; Omar, A.M.; Padin, X.A.; Park, G.-H.; Paterson, K.; Perez, F.F.; Pierrot, D.; Poisson, A.; Rios, A.F.; Salisbury, J.; Santana-Casiano, J.M.; Sarma, V.V.S.S.; et al.

    As a response to public demand for a well-documented, quality controlled, publically available, global surface ocean carbon dioxide (CO<sub>2sub>) data set, the international marine carbon science community developed the Surface Ocean CO<sub>2...

  8. Anthropic reasoning and typicality in multiverse cosmology and string theory

    Energy Technology Data Exchange (ETDEWEB)

    Weinstein, Steven [Perimeter Institute for Theoretical Physics, 31 Caroline St, Waterloo, ON N2L 2Y5 (Canada); Department of Philosophy, University of Waterloo, Waterloo, ON N2L 3G1 (Canada); Department of Physics, University of Waterloo, Waterloo, ON N2L 3G1 (Canada)

    2006-06-21

    Anthropic arguments in multiverse cosmology and string theory rely on the weak anthropic principle (WAP). We show that the principle is fundamentally ambiguous. It can be formulated in one of two ways, which we refer to as WAP{sub 1} and WAP{sub 2}. We show that WAP{sub 2}, the version most commonly used in anthropic reasoning, makes no physical predictions unless supplemented by a further assumption of 'typicality', and we argue that this assumption is both misguided and unjustified. WAP{sub 1}, however, requires no such supplementation; it directly implies that any theory that assigns a non-zero probability to our universe predicts that we will observe our universe with probability one. We argue, therefore, that WAP{sub 1} is preferable, and note that it has the benefit of avoiding the inductive overreach characteristic of much anthropic reasoning.

  9. Statistical test theory for the behavioral sciences

    CERN Document Server

    de Gruijter, Dato N M

    2007-01-01

    Since the development of the first intelligence test in the early 20th century, educational and psychological tests have become important measurement techniques to quantify human behavior. Focusing on this ubiquitous yet fruitful area of research, Statistical Test Theory for the Behavioral Sciences provides both a broad overview and a critical survey of assorted testing theories and models used in psychology, education, and other behavioral science fields. Following a logical progression from basic concepts to more advanced topics, the book first explains classical test theory, covering true score, measurement error, and reliability. It then presents generalizability theory, which provides a framework to deal with various aspects of test scores. In addition, the authors discuss the concept of validity in testing, offering a strategy for evidence-based validity. In the two chapters devoted to item response theory (IRT), the book explores item response models, such as the Rasch model, and applications, incl...

  10. Proportional Reasoning and the Visually Impaired

    Science.gov (United States)

    Hilton, Geoff; Hilton, Annette; Dole, Shelley L.; Goos, Merrilyn; O'Brien, Mia

    2012-01-01

    Proportional reasoning is an important aspect of formal thinking that is acquired during the developmental years that approximate the middle years of schooling. Students who fail to acquire sound proportional reasoning often experience difficulties in subjects that require quantitative thinking, such as science, technology, engineering, and…

  11. Connecting Mathematics Learning through Spatial Reasoning

    Science.gov (United States)

    Mulligan, Joanne; Woolcott, Geoffrey; Mitchelmore, Michael; Davis, Brent

    2018-01-01

    Spatial reasoning, an emerging transdisciplinary area of interest to mathematics education research, is proving integral to all human learning. It is particularly critical to science, technology, engineering and mathematics (STEM) fields. This project will create an innovative knowledge framework based on spatial reasoning that identifies new…

  12. Thermal expansion of superconducting phases Bi sub 2 Sr sub 2 Ca sub n-1 Cu sub n O sub 2n+2+. delta. with n=1,2,3. Termicheskoe rasshirenie sverkhprovodyashchikh faz Bi sub 2 Sr sub 2 Ca sub n-1 Cu sub n O sub 2n+2+. delta. s n=1,2,3

    Energy Technology Data Exchange (ETDEWEB)

    Zhurov, V V; Ivanov, S A [Nauchno-Issledovatel' skij Fiziko-Khimicheskij Inst., Moscow (USSR); Bush, A A; Romanov, B N [Moskovskij Inst. Radiotekhniki, Ehlektroniki i Avtomatiki, Moscow (USSR)

    1990-10-01

    Consideration is given to results of X-ray diffraction studies of temperature dependences of a{sub 0},c{sub 0} sublattice parameters of Bi{sub 2}Sr{sub 2}Ca{sub n-1}Cu{sub n}O{sub 2n+2+}{delta} superconducting phases with n=1,2,3 (2201, 2212, 2223) in 90-1000 K range. The obtained dependences are composed of some temperature linear sections, where values of thermal coefficients of linear expansion {alpha}{sub a}, {alpha}{sub c} were determined for all examined phases. During first heating of samples of 2212 phase a{sub 0}(T), c{sub 0}(T) dependences deviate in {approx equal}500-700 K range from linear ones till the occurence of a section with negative a{sub c}. After heating of 2212 phase up to T>{approx equal}700 K and cooling down to 300 K, a{sub 0},c{sub 0} parameters decrease by {approx equal}0.006 and 0.08 A respectively. Data on the effect of preparation method and thermal prehistory of 2212 samples and on relative content of calcium atoms in them for these anomalies were obtained. Some possible reasons of their occurence were analyzed.

  13. Combined effects Na and SO{sub 2} in flue gas on Mn-Ce/TiO{sub 2} catalyst for low temperature selective catalytic reduction of NO by NH{sub 3} simulated by Na{sub 2}SO{sub 4} doping

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Aiyi [Department of Environmental Science and Engineering, Nanjing Normal University, Nanjing 210023 (China); Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing 210023 (China); Yu, Danqing [School of Chemical Engineering and Technology, Wuhan University of Science and Technology, Wuhan 430081 (China); Yang, Liu [Department of Environmental Science and Engineering, Nanjing Normal University, Nanjing 210023 (China); Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing 210023 (China); Sheng, Zhongyi, E-mail: 09377@njnu.edu.cn [Department of Environmental Science and Engineering, Nanjing Normal University, Nanjing 210023 (China); Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing 210023 (China)

    2016-08-15

    Highlights: • Sodium sulfate (Na{sub 2}SO{sub 4}) was deposited on Mn-Ce/TiO{sub 2} catalyst to simulate the co-existing of sodium and SO{sub 2} in the flue gas. • Na{sub 2}SO{sub 4} had strong and fluctuant influence on Mn-Ce/TiO{sub 2} catalyst’s performance in SCR of NOx with NH{sub 3}, due to the combined effect of the deactivation of sodium salts and the enhanced performance of ceria with surface sulfation. • The changes of the surface chemical species and acid sites on the Na{sub 2}SO{sub 4} deposited catalysts could be considered as the main reasons for the fluctuation changes with the catalytic activity. - Abstract: A series of Mn-Ce/TiO{sub 2} catalysts were synthesized through an impregnation method and used for low temperature selective catalytic reduction (SCR) of NOx with ammonia (NH{sub 3}). Na{sub 2}SO{sub 4} was added into the catalyst to simulate the combined effects of alkali metal and SO{sub 2} in the flue gas. Experimental results showed that Na{sub 2}SO{sub 4} had strong and fluctuant influence on the activity of Mn-Ce/TiO{sub 2}, because the effect of Na{sub 2}SO{sub 4} included pore occlusion and sulfation effect simultaneously. When Na{sub 2}SO{sub 4} loading content increased from 0 to 1 wt.%, the SCR activities of Na{sub 2}SO{sub 4}-doped catalysts decreased greatly. With further increasing amount of Na{sub 2}SO{sub 4}, however, the catalytic activity increased gradually. XRD results showed that Na{sub 2}SO{sub 4} doping could induce the crystallization of MnOx phases, which were also confirmed by TEM and SEM results. BET results showed that the surface areas decreased and a new bimodal mesoporous structure formed gradually with the increasing amount of Na{sub 2}SO{sub 4}. XPS results indicated that part of Ce{sup 4+} and Mn{sup 3+} were transferred to Ce{sup 3+} and Mn{sup 4+} due to the sulfation after Na{sub 2}SO{sub 4} deposition on the surface of the catalysts. When the doped amounts of Na{sub 2}SO{sub 4} increased, NH{sub 3

  14. Defects spectroscopy by means of the simple trapping model of the Fe{sub 78}Si{sub 9}B{sub 13} alloy; Espectroscopia de defectos mediante el modelo de atrapamiento simple de la aleacion Fe{sub 78}Si{sub 9}B{sub 13}

    Energy Technology Data Exchange (ETDEWEB)

    Lopez M, A.; Cabral P, A.; Garcia S, S.F. [Laboratorio de Fisica Avanzada, Facultad de Ciencias, Universidad Autonoma del Estado de Mexico. El Cerillo Piedras Blancas, 50000 Toluca, Estado de Mexico (Mexico)

    2007-07-01

    In this work it is analyzed quantitatively the results of the positron annihilation in the Fe{sub 78}Si{sub 9}B{sub 13} alloy by means of the simple trapping model. From this analysis its are derived: a reason of positron trapping in the defects (K), the defects concentration (C{sub d}) and the electronic density associated to the defect (n{sub d}); both first parameters, (K, C{sub d}) its increase and n{sub d} diminishes when increasing the alloy temperature. From this analysis it is also inferred that the defect consists of a multi vacancy of between 15 and 20 mono vacancies. (Author)

  15. The Model Identification Test: A Limited Verbal Science Test

    Science.gov (United States)

    McIntyre, P. J.

    1972-01-01

    Describes the production of a test with a low verbal load for use with elementary school science students. Animated films were used to present appropriate and inappropriate models of the behavior of particles of matter. (AL)

  16. Sadhana | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    ... creep strength the sub-grain structure produced under different conditions is most important. The changes in the microstructure mean that great care is needed in the extrapolation of experimental data to obtain design values. Only data from tests with rupture times above 3,000 h provide reasonable extrapolated values.

  17. Science in an age of (non)reason

    DEFF Research Database (Denmark)

    Porter, John R; Wollenweber, Bernd

    2018-01-01

    In this chapter, we wish to reflect on some of the issues we see as affecting our work, how we see the ethos of our research institutions changing, the role of science in an age in which ‘experts’ are seen as an unnecessary luxury who stand in the way of popular and populist movements but in which......, at the same time, people crave the products invented, developed and produced by such ‘experts’. We take a structured approach that uses the norms of science defined by the social scientist Robert Merton (the so-called Mertonian norms) and examine how each of them is affected by the current climate for science...

  18. Longitudinal analysis of standardized test scores of students in the Science Writing Heuristic approach

    Science.gov (United States)

    Chanlen, Niphon

    The purpose of this study was to examine the longitudinal impacts of the Science Writing Heuristic (SWH) approach on student science achievement measured by the Iowa Test of Basic Skills (ITBS). A number of studies have reported positive impact of an inquiry-based instruction on student achievement, critical thinking skills, reasoning skills, attitude toward science, etc. So far, studies have focused on exploring how an intervention affects student achievement using teacher/researcher-generated measurement. Only a few studies have attempted to explore the long-term impacts of an intervention on student science achievement measured by standardized tests. The students' science and reading ITBS data was collected from 2000 to 2011 from a school district which had adopted the SWH approach as the main approach in science classrooms since 2002. The data consisted of 12,350 data points from 3,039 students. The multilevel model for change with discontinuity in elevation and slope technique was used to analyze changes in student science achievement growth trajectories prior and after adopting the SWH approach. The results showed that the SWH approach positively impacted students by initially raising science achievement scores. The initial impact was maintained and gradually increased when students were continuously exposed to the SWH approach. Disadvantaged students who were at risk of having low science achievement had bigger benefits from experience with the SWH approach. As a result, existing problematic achievement gaps were narrowed down. Moreover, students who started experience with the SWH approach as early as elementary school seemed to have better science achievement growth compared to students who started experiencing with the SWH approach only in high school. The results found in this study not only confirmed the positive impacts of the SWH approach on student achievement, but also demonstrated additive impacts found when students had longitudinal experiences

  19. Assessing Differential Item Functioning on the Test of Relational Reasoning

    Directory of Open Access Journals (Sweden)

    Denis Dumas

    2018-03-01

    Full Text Available The test of relational reasoning (TORR is designed to assess the ability to identify complex patterns within visuospatial stimuli. The TORR is designed for use in school and university settings, and therefore, its measurement invariance across diverse groups is critical. In this investigation, a large sample, representative of a major university on key demographic variables, was collected, and the resulting data were analyzed using a multi-group, multidimensional item-response theory model-comparison procedure. No significant differential item functioning was found on any of the TORR items across any of the demographic groups of interest. This finding is interpreted as evidence of the cultural fairness of the TORR, and potential test-development choices that may have contributed to that cultural fairness are discussed.

  20. Using Computer Simulations for Promoting Model-based Reasoning. Epistemological and Educational Dimensions

    Science.gov (United States)

    Develaki, Maria

    2017-11-01

    Scientific reasoning is particularly pertinent to science education since it is closely related to the content and methodologies of science and contributes to scientific literacy. Much of the research in science education investigates the appropriate framework and teaching methods and tools needed to promote students' ability to reason and evaluate in a scientific way. This paper aims (a) to contribute to an extended understanding of the nature and pedagogical importance of model-based reasoning and (b) to exemplify how using computer simulations can support students' model-based reasoning. We provide first a background for both scientific reasoning and computer simulations, based on the relevant philosophical views and the related educational discussion. This background suggests that the model-based framework provides an epistemologically valid and pedagogically appropriate basis for teaching scientific reasoning and for helping students develop sounder reasoning and decision-taking abilities and explains how using computer simulations can foster these abilities. We then provide some examples illustrating the use of computer simulations to support model-based reasoning and evaluation activities in the classroom. The examples reflect the procedure and criteria for evaluating models in science and demonstrate the educational advantages of their application in classroom reasoning activities.

  1. Testing of HTR UO{sub 2} TRISO fuels in AVR and in material test reactors

    Energy Technology Data Exchange (ETDEWEB)

    Kania, Michael J., E-mail: MichaelJKania@googlemail.com [Retired from Lockheed Martin Corp, 20 Beach Road, Averill Park, NY 12018 (United States); Nabielek, Heinz, E-mail: heinznabielek@me.com [Retired from Research Center Jülich, Monschauerstrasse 61, 52355 Düren (Germany); Verfondern, Karl [Research Center Juelich,Research Center Jülich, Institute of Energy and Climate Research, 52425 Jülich (Germany); Allelein, Hans-Josef [Research Center Juelich,Research Center Jülich, Institute of Energy and Climate Research, 52425 Jülich (Germany); RWTH Aachen, 52072 Aachen (Germany)

    2013-10-15

    The German High Temperature Reactor Fuel Development Program successfully developed, licensed and manufactured many thousands of spherical fuel elements that were used to power the experimental AVR reactor and the commercial THTR reactor. In the 1970s, this program extended the performance envelope of HTR fuels by developing and qualifying the TRISO-coated particle system. Irradiation testing in real-time AVR tests and accelerated MTR tests demonstrated the superior manufacturing process of this fuel and its irradiation performance. In the 1980s, another program direction change was made to a low enriched UO{sub 2} TRISO-coated particle system coupled with high-quality manufacturing specifications designed to meet new HTR plant design needs. These needs included requirements for inherent safety under normal operation and accident conditions. Again, the German fuel development program met and exceeded these challenges by manufacturing and qualifying the low-enriched UO{sub 2} TRISO-fuel system for HTR systems with steam generation, gas-turbine systems and very high temperature process heat applications. Fuel elements were manufactured in production scale facilities that contained near defect free UO{sub 2} TRISO coated particles, homogeneously distributed within a graphite matrix with very low levels of uranium contamination. Good irradiation performance for these elements was demonstrated under normal operating conditions to 12% FIMA and under accident conditions not exceeding 1600 °C.

  2. Elementary Children's Retrodictive Reasoning about Earth Science

    Science.gov (United States)

    Libarkin, Julie C.; Schneps, Matthew H.

    2012-01-01

    We report on interviews conducted with twenty-one elementary school children (grades 1-5) about a number of Earth science concepts. These interviews were undertaken as part of a teacher training video series designed specifically to assist elementary teachers in learning essential ideas in Earth science. As such, children were interviewed about a…

  3. Tracing Young Children's Scientific Reasoning

    Science.gov (United States)

    Tytler, Russell; Peterson, Suzanne

    2003-08-01

    This paper explores the scientific reasoning of 14 children across their first two years of primary school. Children's view of experimentation, their approach to exploration, and their negotiation of competing knowledge claims, are interpreted in terms of categories of epistemological reasoning. Children's epistemological reasoning is distinguished from their ability to control variables. While individual children differ substantially, they show a relatively steady growth in their reasoning, with some contextual variation. A number of these children are reasoning at a level well in advance of curriculum expectations, and it is argued that current recommended practice in primary science needs to be rethought. The data is used to explore the relationship between reasoning and knowledge, and to argue that the generation and exploration of ideas must be the key driver of scientific activity in the primary school.

  4. Physical experience enhances science learning.

    Science.gov (United States)

    Kontra, Carly; Lyons, Daniel J; Fischer, Susan M; Beilock, Sian L

    2015-06-01

    Three laboratory experiments involving students' behavior and brain imaging and one randomized field experiment in a college physics class explored the importance of physical experience in science learning. We reasoned that students' understanding of science concepts such as torque and angular momentum is aided by activation of sensorimotor brain systems that add kinetic detail and meaning to students' thinking. We tested whether physical experience with angular momentum increases involvement of sensorimotor brain systems during students' subsequent reasoning and whether this involvement aids their understanding. The physical experience, a brief exposure to forces associated with angular momentum, significantly improved quiz scores. Moreover, improved performance was explained by activation of sensorimotor brain regions when students later reasoned about angular momentum. This finding specifies a mechanism underlying the value of physical experience in science education and leads the way for classroom practices in which experience with the physical world is an integral part of learning. © The Author(s) 2015.

  5. Ultrasonic study of the charge mismatch effect in charge-ordered (Nd{sub 0.75}Na{sub 0.25}){sub x}(Nd{sub 0.5}Ca{sub 0.5}){sub 1-x}MnO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Jiang Liang; Su Jinrui; Kong Hui; Liu Yi; Zheng Shiyuan; Zhu Changfei [Laboratory of Advanced Functional Materials and Devices, Department of Materials Science and Engineering, University of Science and Technology of China, Hefei 230026 (China)

    2006-09-20

    The resistivity, magnetization and ultrasonic properties of charge-ordered polycrystalline (Nd{sub 0.75}Na{sub 0.25}){sub x}(Nd{sub 0.5}Ca{sub 0.5}){sub 1-x}MnO{sub 3} have been investigated from 50 to 300 K. A considerable velocity softening accompanied by an attenuation peak was observed around the charge-ordering transition temperature (T{sub CO}) upon cooling. The simultaneous occurrence of the charge ordering (CO) and the ultrasonic anomaly implies strong electron-phonon coupling, which originates from the cooperative Jahn-Teller effect. At very low temperature, another broad attenuation peak was observed, which is attributed to the phase separation (PS) and gives a direct evidence of spin-phonon coupling in the compound. With increasing x, T{sub CO} shifts to lower temperature, the magnetization of the system is strengthened and the PS is enhanced. The temperature dependence of the longitudinal modulus shows that the Jahn-Teller coupling energy E{sub JT} decreases with increasing Na content. The analysis suggests that the charge mismatch effect may be the main reason for the suppression of the CO and enhancement of the PS.

  6. Intermediate Scale Laboratory Testing to Understand Mechanisms of Capillary and Dissolution Trapping during Injection and Post-Injection of CO<sub>2sub> in Heterogeneous Geological Formations

    Energy Technology Data Exchange (ETDEWEB)

    Illangasekare, Tissa [Colorado School of Mines, Golden, CO (United States); Trevisan, Luca [Colorado School of Mines, Golden, CO (United States); Agartan, Elif [Colorado School of Mines, Golden, CO (United States); Mori, Hiroko [Colorado School of Mines, Golden, CO (United States); Vargas-Johnson, Javier [Colorado School of Mines, Golden, CO (United States); Gonzalez-Nicolas, Ana [Colorado School of Mines, Golden, CO (United States); Cihan, Abdullah [Colorado School of Mines, Golden, CO (United States); Birkholzer, Jens [Colorado School of Mines, Golden, CO (United States); Zhou, Quanlin [Colorado School of Mines, Golden, CO (United States)

    2015-03-31

    Carbon Capture and Storage (CCS) represents a technology aimed to reduce atmospheric loading of CO<sub>2sub> from power plants and heavy industries by injecting it into deep geological formations, such as saline aquifers. A number of trapping mechanisms contribute to effective and secure storage of the injected CO<sub>2sub> in supercritical fluid phase (scCO<sub>2sub>) in the formation over the long term. The primary trapping mechanisms are structural, residual, dissolution and mineralization. Knowledge gaps exist on how the heterogeneity of the formation manifested at all scales from the pore to the site scales affects trapping and parameterization of contributing mechanisms in models. An experimental and modeling study was conducted to fill these knowledge gaps. Experimental investigation of fundamental processes and mechanisms in field settings is not possible as it is not feasible to fully characterize the geologic heterogeneity at all relevant scales and gathering data on migration, trapping and dissolution of scCO<sub>2sub>. Laboratory experiments using scCO<sub>2sub> under ambient conditions are also not feasible as it is technically challenging and cost prohibitive to develop large, two- or three-dimensional test systems with controlled high pressures to keep the scCO<sub>2sub> as a liquid. Hence, an innovative approach that used surrogate fluids in place of scCO<sub>2sub> and formation brine in multi-scale, synthetic aquifers test systems ranging in scales from centimeter to meter scale developed used. New modeling algorithms were developed to capture the processes controlled by the formation heterogeneity, and they were tested using the data from the laboratory test systems. The results and findings are expected to contribute toward better conceptual models, future improvements to DOE numerical codes, more accurate assessment of storage capacities, and optimized placement strategies. This report presents the experimental and modeling methods

  7. Towards a General Scientific Reasoning Engine.

    Science.gov (United States)

    Carbonell, Jaime G.; And Others

    Expert reasoning in the natural sciences appears to make extensive use of a relatively small number of general principles and reasoning strategies, each associated with a larger number of more specific inference patterns. Using a dual declarative hierarchy to represent strategic and factual knowledge, a framework for a robust scientific reasoning…

  8. Explanatory Item Response Modeling of Children's Change on a Dynamic Test of Analogical Reasoning

    Science.gov (United States)

    Stevenson, Claire E.; Hickendorff, Marian; Resing, Wilma C. M.; Heiser, Willem J.; de Boeck, Paul A. L.

    2013-01-01

    Dynamic testing is an assessment method in which training is incorporated into the procedure with the aim of gauging cognitive potential. Large individual differences are present in children's ability to profit from training in analogical reasoning. The aim of this experiment was to investigate sources of these differences on a dynamic test of…

  9. Molecular CsF{sub 5} and CsF{sub 2}{sup +}

    Energy Technology Data Exchange (ETDEWEB)

    Rogachev, Andrey Yu. [Illinois Institute of Technology, IL (United States). Dept. of Biological and Chemical Sciences; Miao, Mao-sheng [California State Univ., Northridge, CA (United States). Dept. of Chemistry and Biochemistry; Beijing Computational Science Research Center (China); Merino, Gabriel [Centro de Investigacion y de Estudios Avanzados, Unidad Merida (Mexico). Dept. de Fisica Aplicada; Hoffmann, Roald [Cornell Univ., Ithaca, NY (United States). Dept. of Chemistry and Chemical Biology

    2015-07-06

    D{sub 5h} star-like CsF{sub 5}, formally isoelectronic with known XeF{sub 5}{sup -} ion, is computed to be a local minimum on the potential energy surface of CsF{sub 5}, surrounded by reasonably large activation energies for its exothermic decomposition to CsF + 2F{sub 2}, or to CsF{sub 3} (three isomeric forms) + F{sub 2}, or for rearrangement to a significantly more stable isomer, a classical Cs{sup +} complex of F{sub 5}{sup -}. Similarly the CsF{sub 2}{sup +} ion is computed to be metastable in two isomeric forms. In the more symmetrical structures of these molecules there is definite involvement in bonding of the formally core 5p levels of Cs.

  10. VUV Testing of Science Cameras at MSFC: QE Measurement of the CLASP Flight Cameras

    Science.gov (United States)

    Champey, Patrick R.; Kobayashi, Ken; Winebarger, A.; Cirtain, J.; Hyde, D.; Robertson, B.; Beabout, B.; Beabout, D.; Stewart, M.

    2015-01-01

    The NASA Marshall Space Flight Center (MSFC) has developed a science camera suitable for sub-orbital missions for observations in the UV, EUV and soft X-ray. Six cameras were built and tested for the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP), a joint National Astronomical Observatory of Japan (NAOJ) and MSFC sounding rocket mission. The CLASP camera design includes a frame-transfer e2v CCD57-10 512x512 detector, dual channel analog readout electronics and an internally mounted cold block. At the flight operating temperature of -20 C, the CLASP cameras achieved the low-noise performance requirements (less than or equal to 25 e- read noise and greater than or equal to 10 e-/sec/pix dark current), in addition to maintaining a stable gain of approximately equal to 2.0 e-/DN. The e2v CCD57-10 detectors were coated with Lumogen-E to improve quantum efficiency (QE) at the Lyman- wavelength. A vacuum ultra-violet (VUV) monochromator and a NIST calibrated photodiode were employed to measure the QE of each camera. Four flight-like cameras were tested in a high-vacuum chamber, which was configured to operate several tests intended to verify the QE, gain, read noise, dark current and residual non-linearity of the CCD. We present and discuss the QE measurements performed on the CLASP cameras. We also discuss the high-vacuum system outfitted for testing of UV and EUV science cameras at MSFC.

  11. Predictors of HIV Testing among Youth in Sub-Saharan Africa: A Cross-Sectional Study.

    Science.gov (United States)

    Asaolu, Ibitola O; Gunn, Jayleen K; Center, Katherine E; Koss, Mary P; Iwelunmor, Juliet I; Ehiri, John E

    2016-01-01

    In spite of a high prevalence of HIV infection among adolescents and young adults in sub-Saharan Africa, uptake of HIV testing and counseling among youth in the region remains sub-optimal. The objective of this study was to assess factors that influence uptake of HIV testing and counseling among youth aged 15-24 years in sub-Saharan Africa. This study used the Demographic and Health Survey (DHS) data from countries that represent four geographic regions of sub-Saharan Africa: Congo (Brazzaville), representing central Africa (DHS 2011-2012); Mozambique, representing southern Africa (DHS 2011); Nigeria, representing western Africa (DHS 2013); and Uganda, representing eastern Africa (DHS 2011). Analyses were restricted to 23,367 male and female respondents aged 15-24 years with complete data on the variables of interest. Chi-square tests and logistic regression models were used to assess predictors of HIV testing. Statistical significance was set at psub-Saharan Africa for HIV testing continues to be a challenge. Public health programs that seek to increase HIV counseling and testing among youth should pay particular attention to efforts that target high-risk subpopulations of youth. The results further suggest that these initiatives would be strengthened by including strategies to increase HIV comprehensive knowledge.

  12. Scientific Facts and Methods in Public Reason

    DEFF Research Database (Denmark)

    Jønch-Clausen, Karin; Kappel, Klemens

    2016-01-01

    Should scientific facts and methods have an epistemically privileged status in public reason? In Rawls’s public reason account he asserts what we will label the Scientific Standard Stricture: citizens engaged in public reason must be guided by non-controversial scientific methods, and public reason...... must be in line with non-controversial scientific conclusions. The Scientific Standard Stricture is meant to fulfill important tasks such as enabling the determinateness and publicity of the public reason framework. However, Rawls leaves us without elucidation with regard to when science...

  13. Ideology, motivated reasoning, and cognitive reflection

    Directory of Open Access Journals (Sweden)

    Dan M. Kahan

    2013-07-01

    Full Text Available Decision scientists have identified various plausible sources of ideological polarization over climate change, gun violence, national security, and like issues that turn on empirical evidence. This paper describes a study of three of them: the predominance of heuristic-driven information processing by members of the public; ideologically motivated reasoning; and the cognitive-style correlates of political conservativism. The study generated both observational and experimental data inconsistent with the hypothesis that political conservatism is distinctively associated with either unreflective thinking or motivated reasoning. Conservatives did no better or worse than liberals on the Cognitive Reflection Test (Frederick, 2005, an objective measure of information-processing dispositions associated with cognitive biases. In addition, the study found that ideologically motivated reasoning is not a consequence of over-reliance on heuristic or intuitive forms of reasoning generally. On the contrary, subjects who scored highest in cognitive reflection were the most likely to display ideologically motivated cognition. These findings corroborated an alternative hypothesis, which identifies ideologically motivated cognition as a form of information processing that promotes individuals' interests in forming and maintaining beliefs that signify their loyalty to important affinity groups. The paper discusses the practical significance of these findings, including the need to develop science communication strategies that shield policy-relevant facts from the influences that turn them into divisive symbols of political identity.

  14. Development of the Statistical Reasoning in Biology Concept Inventory (SRBCI).

    Science.gov (United States)

    Deane, Thomas; Nomme, Kathy; Jeffery, Erica; Pollock, Carol; Birol, Gülnur

    2016-01-01

    We followed established best practices in concept inventory design and developed a 12-item inventory to assess student ability in statistical reasoning in biology (Statistical Reasoning in Biology Concept Inventory [SRBCI]). It is important to assess student thinking in this conceptual area, because it is a fundamental requirement of being statistically literate and associated skills are needed in almost all walks of life. Despite this, previous work shows that non-expert-like thinking in statistical reasoning is common, even after instruction. As science educators, our goal should be to move students along a novice-to-expert spectrum, which could be achieved with growing experience in statistical reasoning. We used item response theory analyses (the one-parameter Rasch model and associated analyses) to assess responses gathered from biology students in two populations at a large research university in Canada in order to test SRBCI's robustness and sensitivity in capturing useful data relating to the students' conceptual ability in statistical reasoning. Our analyses indicated that SRBCI is a unidimensional construct, with items that vary widely in difficulty and provide useful information about such student ability. SRBCI should be useful as a diagnostic tool in a variety of biology settings and as a means of measuring the success of teaching interventions designed to improve statistical reasoning skills. © 2016 T. Deane et al. CBE—Life Sciences Education © 2016 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  15. Assessing clinical reasoning in optometry using the script concordance test.

    Science.gov (United States)

    Faucher, Caroline; Dufour-Guindon, Marie-Pier; Lapointe, Gabrielle; Gagnon, Robert; Charlin, Bernard

    2016-05-01

    Clinical reasoning is central to any health profession but its development among learners is difficult to assess. Over the last few decades, the script concordance test (SCT) has been developed to solve this dilemma and has been used in many health professions; however, no study has been published on the use of the script concordance test in optometry. The purpose of this study was to develop and validate a script concordance test for the field of optometry. A 101-question script concordance test (27 short clinical scenarios) was developed and administered online to a convenience sample of 23 second-year and 19 fourth-year students of optometry. It was also administered to a reference panel of 12 experienced optometrists to develop the scoring key. An item-total correlation was calculated for each question. Cronbach's alpha coefficient was used to evaluate the script concordance test reliability and a t-test compared the two groups. A final 77-question script concordance test was created by eliminating questions with low item-total correlation. Cronbach's alpha for this optimised 77-question script concordance test was 0.80. A group comparison revealed that the second-year students' scores (n = 23; mean score = 66.4 ± 7.87 per cent) were statistically lower (t = -4.141; p Optometry © 2016 Optometry Australia.

  16. Nuclear Test-Experimental Science: Annual report, fiscal year 1988

    Energy Technology Data Exchange (ETDEWEB)

    Struble, G.L.; Donohue, M.L.; Bucciarelli, G.; Hymer, J.D.; Kirvel, R.D.; Middleton, C.; Prono, J.; Reid, S.; Strack, B. (eds.)

    1988-01-01

    Fiscal year 1988 has been a significant, rewarding, and exciting period for Lawrence Livermore National Laboratory's nuclear testing program. It was significant in that the Laboratory's new director chose to focus strongly on the program's activities and to commit to a revitalized emphasis on testing and the experimental science that underlies it. It was rewarding in that revolutionary new measurement techniques were fielded on recent important and highly complicated underground nuclear tests with truly incredible results. And it was exciting in that the sophisticated and fundamental problems of weapons science that are now being addressed experimentally are yielding new challenges and understanding in ways that stimulate and reward the brightest and best of scientists. During FY88 the program was reorganized to emphasize our commitment to experimental science. The name of the program was changed to reflect this commitment, becoming the Nuclear Test-Experimental Science (NTES) Program.

  17. Forged HITEMAL: Al-based MMCs strengthened with nanometric thick Al{sub 2}O{sub 3} skeleton

    Energy Technology Data Exchange (ETDEWEB)

    Balog, Martin, E-mail: ummsbama@savba.sk [Institute of Materials and Machine Mechanics, Slovak Academy of Sciences, Racianska 75, 83102 Bratislava (Slovakia); Krizik, Peter; Nosko, Martin; Hajovska, Zuzana [Institute of Materials and Machine Mechanics, Slovak Academy of Sciences, Racianska 75, 83102 Bratislava (Slovakia); Victoria Castro Riglos, Maria [Centro Atómico Bariloche, Av. Bustillo 9.500, 8400 Bariloche, Río Negro (Argentina); Rajner, Walter [New Materials Development GmbH, Römerstrasse 28, 83410 Laufen, Leobendorf (Germany); Liu, De-Shin [National Chung Cheng University, 168 University Rd., Min-Hsiung, 62102 Chia-Yi, Taiwan (China); Simancik, Frantisek [Institute of Materials and Machine Mechanics, Slovak Academy of Sciences, Racianska 75, 83102 Bratislava (Slovakia)

    2014-09-08

    Bulk Al–Al{sub 2}O{sub 3} metal matrix composites (MMCs) named HITEMAL (high temperature aluminum) were fabricated in situ by forging compaction of five different types of gas-atomized commercial purity Al powders with a mean particle size in the range of 1–9 µm. As-forged HITEMAL consisted of (sub)micrometric Al grains (matrix) decorated with nanometric thick amorphous Al{sub 2}O{sub 3} (a-Al{sub 2}O{sub 3}) skeleton. Low-angle grain boundaries (LAGBs) free of Al{sub 2}O{sub 3} were located in the Al grain interior. The Al grain size and the portion of LAGBs increased with the increase in the relative powder surface area. As-forged HITEMAL shows excellent thermal stability up to 400 °C for 24 h. Annealing at temperatures ≥450 °C led to crystallization and morphological transformation from a-Al{sub 2}O{sub 3} skeleton to nanometric γ-Al{sub 2}O{sub 3} particles. Owing to the pinning effect of Al{sub 2}O{sub 3} phase, no Al grain growth took place during annealing up to 500 °C. HITEMAL showed attractive mechanical properties especially when tested at 300 °C (yield strength up to 220 MPa, Young's modulus up to 58 GPa). Despite the presence of a nearly continuous a-Al{sub 2}O{sub 3} skeleton along adjacent Al grains, forged HITEMAL materials had reasonable room temperature elongation of 7–26%. HITEMAL's elongation decreased as the Al grain size decreased and with increased testing temperature. The loss in elongation (uniform and total) was attributed to the inhomogeneous flow, which occurred due to high densities of high angle grain boundaries (dislocation sinks) and small content of LAGBs. The strength of HITEMAL stemmed from grain boundary mediated strengthening mechanisms. The results showed a positive deviation from the Hall–Petch plot, which is typical behavior of ultrafine-grained metals. Transformation of a-Al{sub 2}O{sub 3} skeleton to γ-Al{sub 2}O{sub 3} particles led to deterioration of the HITEMAL strength and Young's modulus.

  18. Profile of Students’ Critical Thinking Skill Measured by Science Virtual Test on Living Things and Environmental Sustainability Theme

    Science.gov (United States)

    Maulida, N. I.; Firman, H.; Rusyati, L.

    2017-02-01

    The aims of this study are: (1) to investigate the level of students’ critical thinking skill on living things and environmental sustainability theme for each Inch’ critical thinking elements and overall, (2) to investigate the level of students’ critical thinking skill on living things characteristic, biodiversity, energy resources, ecosystem, environmental pollution, and global warming topics. The research was conducted due to the important of critical thinking measurement to get the current skill description as the basic consideration for further critical thinking skill improvement in lower secondary science. The research method used was descriptive. 331 seventh grade students taken from five lower secondary schools in Cirebon were tested to get the critical thinking skill data by using Science Virtual Test as the instrument. Generally, the mean scores on eight Inch’ critical thinking elements and overall score from descriptive statistic reveals a moderate attainments level. Students’ critical thinking skill on biodiversity, energy resources, ecosystem, environmental pollution, and global warming topics are in moderate level. While students’ critical thinking skill on living things characteristic is identified as high level. Students’ experience in thinking critically during science learning process and the characteristic of the topic are emerged as the reason behind the students’ critical thinking skill level on certain science topic.

  19. Graphene supported Li{sub 2}SiO{sub 3}/Li{sub 4}Ti{sub 5}O{sub 12} nanocomposites with improved electrochemical performance as anode material for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Qiufen, E-mail: grp2009wqf@163.com; Yang, Shuai; Miao, Juan, E-mail: miaojuan@hpu.edu.cn; Lu, Mengwei; Wen, Tao; Sun, Jiufang

    2017-05-01

    Highlights: • We synthesized Graphene supported Li{sub 2}SiO{sub 3}@Li{sub 4}Ti{sub 5}O{sub 12}. • The discharge capacity is 399.2 mAh g{sup −1} at the current density of 150 mA g{sup −1} after 200 cycles. • The charge rate capacities retain 89.1% at the current density from 150 mA g{sup −1} to 750 mA g{sup −1}. • The recovery rates of the charge capacities are 91.0% when returned the current density of 150 mA g{sup −1}. - Abstract: Graphene supported Li{sub 2}SiO{sub 3}@Li{sub 4}Ti{sub 5}O{sub 12} (GE@LSO/LTO) nanocomposites have been synthesized via a hydrothermal route and following calcination. LSO/LTO nanospheres are adhered to the graphene nanosheets with the size of 50–100 nm, in which both LSO and LTO particles are attached together. When tested as the anode for lithium ion batteries, the initial discharge and charge capacities of GE@LSO/LTO are 720.6 mAh g{sup −1} and 463.4 mAh g{sup −1} at the current density of 150 mA g{sup −1}. After 200 cycles, the discharge and charge capacities can be remained of 399.2 mAh g{sup −1} and 398.9 mAh g{sup −1}, respectively. Moreover, the charge rate capacities of GE@LSO/LTO composites retain 89.1% at the range of current density from 150 mA g{sup −1} to 750 mA g{sup −1}. And its recovery rates are 91.0% when the current density back to 150 mA g{sup −1}. In addition, the reversible capacity and cycle stability of GE@LSO/LTO are better than that of LTO and LSO/LTO. The reasons can be attributed to the synergistic effect between GE and LSO/LTO as well as the features of GE supports.

  20. Temperature dependent tunneling study of CaFe{sub 1.96}Ni{sub 0.04}As{sub 2} single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, Anirban, E-mail: adatta@iitk.ac.in; Gupta, Anjan K. [Department of Physics, IIT Kanpur, Kanpur-208 016 (India); Thamizhavel, A. [Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai-400 005 (India)

    2014-04-24

    We report on temperature dependent scanning tunneling microscopy and spectroscopy studies on CaFe{sub 1.96}Ni{sub 0.04}As{sub 2} single crystals in 5.4 – 19.7 K temperature range across the normal metal - superconductor transition temperature, T{sub C} = 14K. The in-situ cleaved crystals show reasonably flat surface with signatures of atomic resolution. The tunnel spectra show significant spatial inhomogeneity below T{sub C}, which reduces significantly as the temperature goes above the T{sub C}. We discuss these results in terms of an inhomogeneous electronic phase that may exist due to the vicinity of this composition to the quantum critical point.

  1. Patterns of Reasoning about Ecological Systemic Reasoning for Early Elementary Students

    Science.gov (United States)

    Hokayem, H.

    2016-01-01

    Systems and system models are recognized as a crosscutting concept in the newly released framework for K-12 science education (NRC [National Research Council], 2012). In previous work, I developed a learning progression for systemic reasoning in ecology at the elementary level. The learning progression captured five levels of students' reasoning…

  2. The Potential of Qualitative Research for Applied Developmental Science in Sub-Saharan Africa

    DEFF Research Database (Denmark)

    Demuth, Carolin

    2017-01-01

    The present chapter addresses how qualitative research can fruitfully contribute to applied developmental science in Sub-Saharan Africa. It starts out by arguing that most research in developmental psychology has been fundamentally flawed by its neglect of the role of culture for our understanding...... procedures to be studied. Qualitative methodologies, particularly ethnographically informed discourse analysis, provide such empirical procedures and allow for a culture-sensitive developmental science. Examples from a recent study on mother-infant interactions among Cameroonian farming Nso families serve...... of healthy child development and biased by a Western notion thereof. It suggests that research in the field needs to be able to provide insights into how children’s experiences are constructed within the bounds of geographical, societal and ideological dispositions and constraints, family structures...

  3. Elevated voltage level I.sub.DDQ failure testing of integrated circuits

    Science.gov (United States)

    Righter, Alan W.

    1996-01-01

    Burn in testing of static CMOS IC's is eliminated by I.sub.DDQ testing at elevated voltage levels. These voltage levels are at least 25% higher than the normal operating voltage for the IC but are below voltage levels that would cause damage to the chip.

  4. Pending laboratory tests and the hospital discharge summary in patients discharged to sub-acute care.

    Science.gov (United States)

    Walz, Stacy E; Smith, Maureen; Cox, Elizabeth; Sattin, Justin; Kind, Amy J H

    2011-04-01

    Previous studies have noted a high (41%) prevalence and poor discharge summary communication of pending laboratory (lab) tests at the time of hospital discharge for general medical patients. However, the prevalence and communication of pending labs within a high-risk population, specifically those patients discharged to sub-acute care (i.e., skilled nursing, rehabilitation, long-term care), remains unknown. To determine the prevalence and nature of lab tests pending at hospital discharge and their inclusion within hospital discharge summaries, for common sub-acute care populations. Retrospective cohort study. Stroke, hip fracture, and cancer patients discharged from a single large academic medical center to sub-acute care, 2003-2005 (N = 564) Pending lab tests were abstracted from the laboratory information system (LIS) and from each patient's discharge summary, then grouped into 14 categories and compared. Microbiology tests were sub-divided by culture type and number of days pending prior to discharge. Of sub-acute care patients, 32% (181/564) were discharged with pending lab tests per the LIS; however, only 11% (20/181) of discharge summaries documented these. Patients most often left the hospital with pending microbiology tests (83% [150/181]), particularly blood and urine cultures, and reference lab tests (17% [30/181]). However, 82% (61/74) of patients' pending urine cultures did not have 24-hour preliminary results, and 19% (13/70) of patients' pending blood cultures did not have 48-hour preliminary results available at the time of hospital discharge. Approximately one-third of the sub-acute care patients in this study had labs pending at discharge, but few were documented within hospital discharge summaries. Even after considering the availability of preliminary microbiology results, these omissions remain common. Future studies should focus on improving the communication of pending lab tests at discharge and evaluating the impact that this improved

  5. Nuclear test-experimental science annual report, Fiscal year 1990

    International Nuclear Information System (INIS)

    Struble, G.L.; Middleton, C.; Anderson, S.E.; Cherniak, J.; Donohue, M.L.; Francke, A.; Hedman, I.; Kirvel, R.D.

    1991-01-01

    Fiscal year 1990 was another year of outstanding accomplishments for the Nuclear Test-Experimental Science (NTES) Program at Lawrence Livermore National Laboratory (LLNL). We continued to make progress to enhance the experimental science in the Weapons Program and to improve the operational efficiency and productivity of the Nuclear Test Program

  6. Enhanced visible light activity on direct contact Z-scheme g-C{sub 3}N{sub 4}-TiO{sub 2} photocatalyst

    Energy Technology Data Exchange (ETDEWEB)

    Li, Juan [National & Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials, Henan University, Kaifeng, 475004 (China); Collaborative Innovation Center of Nano Functional Materials and Applications of Henan Province, Henan University, Kaifeng, 475004 (China); College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004 (China); Zhang, Min [National & Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials, Henan University, Kaifeng, 475004 (China); Collaborative Innovation Center of Nano Functional Materials and Applications of Henan Province, Henan University, Kaifeng, 475004 (China); Li, Qiuye, E-mail: qiuyeli@henu.edu.cn [National & Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials, Henan University, Kaifeng, 475004 (China); Collaborative Innovation Center of Nano Functional Materials and Applications of Henan Province, Henan University, Kaifeng, 475004 (China); Yang, Jianjun, E-mail: yangjianjun@henu.edu.cn [National & Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials, Henan University, Kaifeng, 475004 (China); Collaborative Innovation Center of Nano Functional Materials and Applications of Henan Province, Henan University, Kaifeng, 475004 (China)

    2017-01-01

    Highlights: • The g-C{sub 3}N{sub 4}-TiO{sub 2} composites were obtained by simple solid state sintering. • The composites were direct contact Z-scheme without an electron mediator. • TiO{sub 2} with large amount of SETOV was obtained by dehydration of NTA. - Abstract: Direct contact Z-scheme g-C{sub 3}N{sub 4}-TiO{sub 2} nanocomposites without an electron mediator are prepared via simple annealing the mixture of bulk g-C{sub 3}N{sub 4} and nanotube titanic acid (NTA) in air at 600 °C for 2 h. In the process of annealing, the bulk g-C{sub 3}N{sub 4} transformed to ultra-thin g-C{sub 3}N{sub 4} nanosheets, and NTA converted to a novel anatase TiO{sub 2}, then the two components formed a close interaction. The XPS result reveals that some amount of nitrogen is doped into this novel-TiO{sub 2}, and g-C{sub 3}N{sub 4} nanosheets exist in the composites. The results of XRD, TEM and TG indicate that the thickness of g-C{sub 3}N{sub 4} nanosheets is very thin. The ESR spectrum shows the existence of Ti{sup 3+} and single-electron-trapped oxygen vacancy in the 30%g-C{sub 3}N{sub 4}-TiO{sub 2} composites. In photocatalytic activity test, the 30%g-C{sub 3}N{sub 4}-TiO{sub 2} nanocomposites showed an excellent photo-oxidation activity of propylene under visible light irradiation (λ≥ 420 nm), and the removal efficiency of propylene reached as high as 56.6%, and the activity kept nearly 82% after four consecutive recycles. Photoluminescence (PL) result using terephthalic acid (TA) as a probe molecule indicated that the g-C{sub 3}N{sub 4}-TiO{sub 2} nanocomposites displayed a Z-sheme photocatalytic reaction system and this should be the main reason for the high photocatalytic activity. A possible photocatalytic mechanism was proposed on the basis of PL result and transient photocurrent-time curves.

  7. Scientists Reflect on Why They Chose to Study Science

    Science.gov (United States)

    Venville, Grady; Rennie, Léonie; Hanbury, Colin; Longnecker, Nancy

    2013-12-01

    A concern commonly raised in literature and in media relates to the declining proportions of students who enter and remain in the `science pipeline', and whether many countries, including Australia and New Zealand, have enough budding scientists to fill research and industry positions in the coming years. In addition, there is concern that insufficient numbers of students continue in science to ensure an informed, scientifically literate citizenry. The aim of the research presented in this paper was to survey current Australian and New Zealand scientists to explore their reasons for choosing to study science. An online survey was conducted via a link to SurveyGizmo. The data presented are from 726 respondents who answered 22 forced-choice items and an open-ended question about the reasons they chose to study science. The quantitative data were analysed using t tests and analyses of variance followed by Duncan's multiple range tests, and the qualitative data were analysed thematically. The quantitative data showed that the main reasons scientists reported choosing to study science were because they were interested in science and because they were good at science. Secondary school science classes and one particular science teacher also were found to be important factors. Of much less importance were the prestige of science and financial considerations. The qualitative data expanded on these findings and showed that passion for science and/or curiosity about the world were important factors and also highlighted the importance of recreational pursuits, such as camping when a child. In the words of one respondent, `People don't go into science for the money and glory. It's passion for knowledge and science that always attracted me to the field'.

  8. Logic, Probability, and Human Reasoning

    Science.gov (United States)

    2015-01-01

    accordingly suggest a way to integrate probability and deduction. The nature of deductive reasoning To be rational is to be able to make deductions...3–6] and they underlie mathematics, science, and tech- nology [7–10]. Plato claimed that emotions upset reason- ing. However, individuals in the grip...fundamental to human rationality . So, if counterexamples to its principal predictions occur, the theory will at least explain its own refutation

  9. Elevated voltage level I{sub DDQ} failure testing of integrated circuits

    Science.gov (United States)

    Righter, A.W.

    1996-05-21

    Burn in testing of static CMOS IC`s is eliminated by I{sub DDQ} testing at elevated voltage levels. These voltage levels are at least 25% higher than the normal operating voltage for the IC but are below voltage levels that would cause damage to the chip. 4 figs.

  10. Software Sub-system in Loading Automatic Test System for the Measurement of Power Line Filters

    Directory of Open Access Journals (Sweden)

    Yu Bo

    2017-01-01

    Full Text Available The loading automatic test system for measurement of power line filters are in urgent demand. So the software sub-system of the whole test system was proposed. Methods: structured the test system based on the virtual instrument framework, which consisted of lower and up computer and adopted the top down approach of design to perform the system and its modules, according to the measurement principle of the test system. Results: The software sub-system including human machine interface, data analysis and process software, expert system, communication software, control software in lower computer, etc. had been designed. Furthermore, it had been integrated into the entire test system. Conclusion: This sub-system provided a fiendly software platform for the whole test system, and had many advantages such as strong functions, high performances, low prices. It not only raises the test efficiency of EMI filters, but also renders some creativities.

  11. Scientific reasoning skills of high school students’ relationship gender and their academic success

    OpenAIRE

    Zeynep Demirtaş

    2011-01-01

    This study is aimed to examine the relationships between scientific reasoning skills of high school students and academic success that science (Physics, Chemistry and Biology), language (Turkish Language and Literature with Foreign Language), social (History and Geograpy) and ability groups (Painting, Music and Physical Education). For this purpose a test was executed to 408 first grade students from different seven high schools in Sakarya. Data were collected by a Classroom Test of Scientifi...

  12. Landau-Ginzburg description of anomalous properties of novel room temperature multiferroics Pb(Fe{sub 1/2}Ta{sub 1/2}){sub x}(Zr{sub 0.53}Ti{sub 0.47}){sub 1-x}O{sub 3} and Pb(Fe{sub 1/2}Nb{sub 1/2}){sub x}(Zr{sub 0.53}Ti{sub 0.47}){sub 1−x}O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Glinchuk, Maya D.; Eliseev, Eugene A. [Institute for Problems of Materials Science, National Academy of Sciences of Ukraine, Krjijanovskogo 3, 03142 Kyiv (Ukraine); Morozovska, Anna N., E-mail: anna.n.morozovska@gmail.com [Institute of Physics, National Academy of Sciences of Ukraine, 46, pr. Nauky, 03028 Kyiv (Ukraine)

    2016-01-14

    Landau-Ginzburg thermodynamic formalism is used for the description of the anomalous ferroelectric, ferromagnetic, and magnetoelectric properties of Pb(Fe{sub 1/2}Ta{sub 1/2}){sub x}(Zr{sub 0.53}Ti{sub 0.47}){sub 1−x}O{sub 3} and Pb(Fe{sub 1/2}Nb{sub 1/2}){sub x}(Zr{sub 0.53}Ti{sub 0.47}){sub 1−x}O{sub 3} micro-ceramics. We calculated temperature, composition, and external field dependences of ferroelectric, ferromagnetic, and antiferromagnetic phases transition temperatures, remanent polarization, magnetization, hysteresis loops, dielectric permittivity, and magnetoelectric coupling. Special attention was paid to the comparison of developed theory with experiments. It appeared possible to describe adequately main experimental results including a reasonable agreement between the shape of calculated and measured hysteresis loops and remnant polarization. Since Landau-Ginzburg thermodynamic formalism appertains to single domain properties of a ferroic, we did not aim to describe quantitatively the coercive field under the presence of realistic poly-domain switching. Information about linear and nonlinear magnetoelectric coupling coefficients was extracted from the experimental data. From the fitting of experimental data with theoretical formula, we obtained the composition dependence of Curie-Weiss constant that is known to be inversely proportional to harmonic (linear) dielectric stiffness, as well as the strong nonlinear dependence of anharmonic parameters in free energy. Keeping in mind the essential influence of these parameters on multiferroic properties, the obtained results open the way to govern practically all the material properties with the help of suitable composition choice. A forecast of the strong enough influence of antiferrodistortive order parameter on the transition temperatures and so on the phase diagrams and properties of multiferroics are made on the basis of the developed theory.

  13. Analogical Reasoning in the Classroom: Insights from Cognitive Science

    Science.gov (United States)

    Vendetti, Michael S.; Matlen, Bryan J.; Richland, Lindsey E.; Bunge, Silvia A.

    2015-01-01

    Applying knowledge from one context to another is a notoriously difficult problem, both for children and adults, but lies at the heart of educational endeavors. Analogical reasoning is a cognitive underpinning of the ability to notice and draw similarities across contexts. Reasoning by analogy is especially challenging for students, who must…

  14. Loading clusters composed of nanoparticles on ZrO{sub 2} support via a perovskite-type oxide of La{sub 0.95}Ce{sub 0.05}Co{sub 0.7}Cu{sub 0.3}O{sub 3} for ethanol synthesis from syngas and its structure variation with reaction time

    Energy Technology Data Exchange (ETDEWEB)

    Song, Zhaoyu [Tianjin Key Laboratory of Applied Catalysis Science and Technology, School of Chemical Engineering, Tianjin University, Tianjin 300354 (China); Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300354 (China); Shi, Xiangpeng [Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300354 (China); Key Laboratory of Green Chemical Technology of Ministry of Education, School of Chemical Engineering, Tianjin University, Tianjin 300354 (China); Ning, Hongyan; Liu, Guilong; Zhong, Huixian [Tianjin Key Laboratory of Applied Catalysis Science and Technology, School of Chemical Engineering, Tianjin University, Tianjin 300354 (China); Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300354 (China); Liu, Yuan, E-mail: yuanliu@tju.edu.cn [Tianjin Key Laboratory of Applied Catalysis Science and Technology, School of Chemical Engineering, Tianjin University, Tianjin 300354 (China); Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300354 (China)

    2017-05-31

    Highlights: • La{sub 0.95}Ce{sub 0.05}Co{sub 0.7}Cu{sub 0.3}O{sub 3}/ZrO{sub 2} catalyst has showed good activity and high selectivity to ethanol. • After reaction for 1000 h, the catalyst was covered by a membrane-like coating. • Carbon deposition is the main reason for the deactivation of the catalyst. - Abstract: A new scheme was proposed to intensify interactions between copper with cobalt and between Cu−Co with the promoters, namely, the ions of copper, cobalt, lanthanum and cerium were confined into La{sub 0.95}Ce{sub 0.05}Co{sub 0.7}Cu{sub 0.3}O{sub 3} with perovskite structure and were supported on zirconia. The catalyst was prepared by impregnation method and used for ethanol synthesis (ES) from syngas and was characterized by using XRD, TG, BET, XPS, ICP-MS and TEM techniques. La{sub 0.95}Ce{sub 0.05}Co{sub 0.7}Cu{sub 0.3}O{sub 3}/ZrO{sub 2} showed very good catalytic performance with selectivity to total alcohols higher than 60% and selectivity to ethanol about 50% in the total alcohols. After reduction, clusters composed of Cu−Co alloy nanoparticles, ceria and lanthanum oxide was formed and loaded on zirconia. Investigation on the variation of the catalyst structure with reaction time showed that with the reaction going on, the clusters spread over the surface of ZrO{sub 2} and at last, all the clusters fused together to form a membrane loaded on the ZrO{sub 2} and the whole catalyst was covered by a membrane-like coating formed by Co{sub 2}C. The characterization results showed that the carbon deposition was the main reason for the deactivation of La{sub 0.95}Ce{sub 0.05}Co{sub 0.7}Cu{sub 0.3}O{sub 3}/ZrO{sub 2} catalyst. This catalyst design scheme could be extended for preparing a lot of catalyst for many reactions.

  15. Mathematical reasoning analogies, metaphors, and images

    CERN Document Server

    English, Lyn D

    2013-01-01

    How we reason with mathematical ideas continues to be a fascinating and challenging topic of research--particularly with the rapid and diverse developments in the field of cognitive science that have taken place in recent years. Because it draws on multiple disciplines, including psychology, philosophy, computer science, linguistics, and anthropology, cognitive science provides rich scope for addressing issues that are at the core of mathematical learning. Drawing upon the interdisciplinary nature of cognitive science, this book presents a broadened perspective on mathematics and mat

  16. High-Risk Behaviors among Youth and Their Reasons for Not Getting Tested for HIV

    Science.gov (United States)

    Moyer, Matthew B.; Silvestre, Anthony J.; Lombardi, Emilia L.; Taylor, Christopher A.

    2007-01-01

    Concerned about reports of a 15% decline in HIV testing among high-risk youth in an earlier study in Pittsburgh, this study was initiated to explore reasons why young people are not getting tested for HIV, while gathering data on their respective level of risk taking behaviors. A total of 580 surveys were collected from youth aged between 14 and…

  17. Elementary children’s retrodictive reasoning about earth science

    OpenAIRE

    Matthew H. Schneps; Julie C. Libarkin

    2012-01-01

    We report on interviews conducted with twenty-one elementary school children (grades 1-5) about a number of Earth science concepts. These interviews were undertaken as part of a teacher training video series designed specifically to assist elementary teachers in learning essential ideas in Earth science. As such, children were interviewed about a wide array of earth science concepts, from rock formation to the Earth’s interior. We analyzed interview data primarily to determine whether or not ...

  18. Mechanical properties of ultra-thin HfO{sub 2} films studied by nano scratches tests

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Wei-En; Chang, Yong-Qing [Center for Measurement Standards, Industrial Technology Research Institute, Room 216, Building 8, 321, Kuang Fu Road Sec. 2, Hsinchu, Taiwan (China); Chang, Chia-Wei; Yao, Chih-Kai [Department of Materials Science and Engineering, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China); Liao, Jiunn-Der, E-mail: jdliao@mail.ncku.edu.tw [Department of Materials Science and Engineering, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China); Center for Micro/Nano Science and Technology, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China)

    2013-02-01

    10-nm-thick atomic layer deposited HfO{sub 2} films were characterized in terms of wear resistance and indentation hardness to investigate the thermal annealing induced impacts on mechanical properties. The wear resistance of ultra-thin films at low loads was characterized using nano-scratch tests with an atomic force microscope. The depth of the nano-scratches decreases with increasing annealing temperature, indicating that the hardness of the annealed films increases with the annealing temperatures. Surface nanoindentation was also performed to confirm the nanoscratch test results. The hardness variation of the annealed films is due to the generation of HfSi{sub x}O{sub y} induced by the thermal annealing. X-ray photoelectron spectroscopy measurements proved that the hardness of formed HfSi{sub x}O{sub y} with increasing annealing temperatures. The existence of HfSi{sub x}O{sub y} broadens the interface, and causes the increase of the interfacial layer thickness. As a result, the surface hardness increases with the increasing HfSi{sub x}O{sub y} induced by the thermal annealing. - Highlights: ► Mechanical properties of HfO{sub 2} films were assessed by nano-scratch and indentation. ► Scratch depth of HfO{sub 2} films decreased with the increase of annealing temperatures. ► Nano-hardness of HfO{sub 2} films increased with the increase of annealing temperatures.

  19. Measurements of 222Rn, 220Rn, and CO<sub>2sub> Emissions in Natural CO<sub>2sub> Fields in Wyoming: MVA Techniques for Determining Gas Transport and Caprock Integrity

    Energy Technology Data Exchange (ETDEWEB)

    Kaszuba, John [Univ. of Wyoming, Laramie, WY (United States); Sims, Kenneth [Univ. of Wyoming, Laramie, WY (United States)

    2014-09-30

    correction factors for measuring radon in CO<sub>2sub>-rich environments. A graduate student earned a Master of Science degree for this part of the field program; she is currently employed with a geologic consulting company. Measurement of radon in springs has improved significantly since the field program first began; however, in situ measurement of 222Rn and particularly 220Rn in springs is problematic. Future refinements include simultaneous salinity measurements and systematic corrections, or adjustments to the partition coefficient as needed for more accurate radon concentration determination. A graduate student earned a Master of Science degree for this part of the field program; he is currently employed with a geologic consulting company. Both graduate students are poised to begin work in a CCS technology area. Laboratory experiments evaluated important process-level fundamentals that effect measurements of radon and CO<sub>2sub>. Laboratory tests established that fine-grained source minerals yield higher radon emissivity compared to coarser-sized source minerals; subtleties in the dataset suggest that grain size alone is not fully representative of all the processes controlling the ability of radon to escape its mineral host. Emissivity for both 222Rn and 220Rn increases linearly with temperature due to reaction of rocks with water, consistent with faster diffusion and enhanced mineral dissolution at higher temperatures. The presence of CO<sub>2sub> changes the relative importance of the factors that control release of radon. Emissivity for both 222Rn and 220Rn in CO<sub>2sub>-bearing experiments is greater at all temperatures compared to the experiments without CO<sub>2sub>, but emissivity does not increase as a simple function of temperature. Governing processes may include a balance between enhanced dissolution versus carbonate mineral formation in CO<sub>2sub>-rich waters.

  20. Multiple perspectives on students’ scientific communication & reasoning in chemistry education [VISIONS 2011: Teaching

    Directory of Open Access Journals (Sweden)

    Maik Walpuski

    2012-07-01

    Full Text Available Both students and teachers need different competences for scientific reasoning. Apart from the required content knowledge and the ability of using it adequately, both groups need elaborated knowledge of strategies for decision-making and argumentation. These competences concerning decision-making are highly dependent on how frequently students are given the chance to argue in science classes. This article pools the results of three different research projects in chemistry education which focus on these three aspects: Students’ competences, the classroom situation with regard to communication and reasoning and teachers’ competences. Students’ skills needed for discussing chemistry content and for decision-making in scientific contexts are analyzed first. Following this, the opportunities for improving these skills during science lessons are researched and related to results from a study of teachers’ pedagogical content knowledge (PCK in this domain. The analysis of students’ and teachers’ communication skills is conducted in two different ways which are paper-pencil tests and video analysis. Paper-pencil tests are used to assess students’ performance in reasoning. The test items deal with chemistry-specific situations, including opportunities for decision-making, which are typical of socio-scientific issues (study 1. The study shows that students’ decision-making skills are poor when the topics deal with scientific contexts, but that students perform better when dealing with everyday-life contexts. One reason might be the lack of reasoning in chemistry lessons, as shown by a video study conducted in chemistry classes. Students’ and teachers’ in-class behavior and communication patterns are analyzed with regard to students’ and teachers’ contributions (study 2. The amount and the quality of students’ and teachers’ statements as well as the interactions, especially teachers’ reactions to students’ statements are

  1. A [Mo{sub 2}O{sub 2}S{sub 2}]-based ring system incorporating tartrate as the bridging ligand. Synthesis, structure and catalytic activity of Cs{sub 4}[Mo{sub 2}O{sub 2}(μ-S){sub 2}]{sub 2}(μ{sub 4}-tart){sub 2} (tart=[C{sub 4}H{sub 2}O{sub 6}]{sup 4-})

    Energy Technology Data Exchange (ETDEWEB)

    Qian, Ting-Ting; Cui, Yu-Jie; Xin, Zhifeng; Jia, Ai-Quan; Zhang, Qian-Feng [Anhui Univ. of Technology, Anhui (China). Inst. of Molecular Engineering and Applied Chemistry and Anhui Province Key Lab. of Metallurgy Engineering and Resources Recycling

    2017-08-01

    Treatment of [Mo{sub 2}S{sub 2}O{sub 2}(H{sub 2}O){sub 6}]{sup 2+} with racemic tartaric acid (tartH{sub 4}) in the presence of sodium hydroxide and cesium chloride in aqueous solution led to the isolation of a new tetra-molybdenum ring cluster Cs{sub 4}[Mo{sub 2}O{sub 2}(μ-S){sub 2}]{sub 2}(μ{sub 4}-tart){sub 2}. The cyclic cluster polyanion consists of two dinuclear [Mo{sub 2}O{sub 2}(μ-S){sub 2}]{sup 2+} moieties and two bridging tart{sup 4-} ligands. The cyclic polyoxothiomolybdate cluster, supported on the mesoporous silica SBA-15, was tested for heterogenerous catalysis in thiophene hydrodesulfurization.

  2. Statistical Analysis of CO<sub>2sub> Exposed Wells to Predict Long Term Leakage through the Development of an Integrated Neural-Genetic Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Boyun [Univ. of Louisiana, Lafayette, LA (United States); Duguid, Andrew [Battelle, Columbus, OH (United States); Nygaard, Ronar [Missouri Univ. of Science and Technology, Rolla, MO (United States)

    2017-08-05

    The objective of this project is to develop a computerized statistical model with the Integrated Neural-Genetic Algorithm (INGA) for predicting the probability of long-term leak of wells in CO<sub>2sub> sequestration operations. This object has been accomplished by conducting research in three phases: 1) data mining of CO<sub>2sub>-explosed wells, 2) INGA computer model development, and 3) evaluation of the predictive performance of the computer model with data from field tests. Data mining was conducted for 510 wells in two CO<sub>2sub> sequestration projects in the Texas Gulf Coast region. They are the Hasting West field and Oyster Bayou field in the Southern Texas. Missing wellbore integrity data were estimated using an analytical and Finite Element Method (FEM) model. The INGA was first tested for performances of convergence and computing efficiency with the obtained data set of high dimension. It was concluded that the INGA can handle the gathered data set with good accuracy and reasonable computing time after a reduction of dimension with a grouping mechanism. A computerized statistical model with the INGA was then developed based on data pre-processing and grouping. Comprehensive training and testing of the model were carried out to ensure that the model is accurate and efficient enough for predicting the probability of long-term leak of wells in CO<sub>2sub> sequestration operations. The Cranfield in the southern Mississippi was select as the test site. Observation wells CFU31F2 and CFU31F3 were used for pressure-testing, formation-logging, and cement-sampling. Tools run in the wells include Isolation Scanner, Slim Cement Mapping Tool (SCMT), Cased Hole Formation Dynamics Tester (CHDT), and Mechanical Sidewall Coring Tool (MSCT). Analyses of the obtained data indicate no leak of CO<sub>2sub> cross the cap zone while it is evident that the well cement sheath was invaded by the CO<sub>2sub> from the storage zone. This observation is consistent

  3. How to Reason with Economic Concepts: Cognitive Process of Japanese Undergraduate Students Solving Test Items

    Science.gov (United States)

    Asano, Tadayoshi; Yamaoka, Michio

    2015-01-01

    The authors administered a Japanese version of the Test of Understanding in College Economics, the fourth edition (TUCE-4) to assess the economic literacy of Japanese undergraduate students in 2006 and 2009. These two test results were combined to investigate students' cognitive process or reasoning with specific economic concepts and principles…

  4. Testing CP in K/sub μ/3 decays

    International Nuclear Information System (INIS)

    Leurer, M.

    1989-01-01

    K factories will open the way for high-precision CP tests in K/sub μ/ 3 decays. The standard model does not predict CP breaking in this process. We consider here the effects of nonstandard interactions mediated by vector and scalar particles and by leptoquarks. We show that, for the only experimentally measurable quantity, vector particles alone never induce CP violation, and give a general expression for the CP breaking induced by scalars and leptoquarks

  5. Reactivity feedback coefficients of a material test research reactor fueled with high-density U{sub 3}Si{sub 2} dispersion fuels

    Energy Technology Data Exchange (ETDEWEB)

    Muhammad, Farhan [Department of Nuclear Engineering, Pakistan Institute of Engineering and Applied Sciences, Nilore, Islamabad 45650 (Pakistan)], E-mail: farhan73@hotmail.com; Majid, Asad [Department of Nuclear Engineering, Pakistan Institute of Engineering and Applied Sciences, Nilore, Islamabad 45650 (Pakistan)

    2008-10-15

    The reactivity feedback coefficients of a material test research reactor fueled with high-density U{sub 3}Si{sub 2} dispersion fuels were calculated. For this purpose, the low-density LEU fuel of an MTR was replaced with high-density U{sub 3}Si{sub 2} LEU fuels currently being developed under the RERTR program. Calculations were carried out to find the fuel temperature reactivity coefficient, moderator temperature reactivity coefficient and moderator density reactivity coefficient. Nuclear reactor analysis codes including WIMS-D4 and CITATION were employed to carry out these calculations. It is observed that the average values of fuel temperature reactivity feedback coefficient, moderator temperature reactivity coefficient and moderator density reactivity coefficient from 20 deg. C to 100 deg. C, at the beginning of life, followed the relationships (in units of {delta}k/k x 10{sup -5} K{sup -1}) -2.116 - 0.118 {rho}{sub U}, 0.713 - 37.309/{rho}{sub U} and -12.765 - 34.309/{rho}{sub U}, respectively for 4.0 {<=} {rho}{sub U} (g/cm{sup 3}) {<=} 6.0.

  6. Nano Fe{sub 2}O{sub 3,} clinoptilolite and H{sub 3}PW{sub 12}O{sub 40} as efficient catalysts for solvent-free synthesis of 5(4H)-isoxazolone under microwave irradiation conditions

    Energy Technology Data Exchange (ETDEWEB)

    Fozooni, Samieh, E-mail: samieh.fozooni@uk.ac.ir, E-mail: s_fozooni@yahoo.com [Shahid Bahonar University, Kerman (Iran, Islamic Republic of). Mining Engineering Department. Zarand High Education Center; Hosseinzadeh, Nasrin Gholam; Akhgar, Mohammad Reza [Islamic Azad University, Kerman (Iran, Islamic Republic of). Department of Chemistry; Hamidian, Hooshang [Payame Noor University (PNU), Tehran (Iran, Islamic Republic of). Department of Chemistry

    2013-10-15

    A quick and solvent-free approach involving the exposure of neat reactants to microwave irradiation in conjunction with the use of clinoptilolite, H{sub 3}PW{sub 12}O{sub 40} and Fe{sub 2}O{sub 3} nanoparticle catalysts is described. In this work, condensation of hydroxylamine hydrochloride, sodium acetate, acetoacetic or benzoyl acetic ethyl ester and appropriate aldehydes by employing catalysts gave 5(4H)-isoxazolone only in one step. Catalyst amount, temperature effects and catalysts reusability were monitored. Among the catalysts, Fe{sub 2}O{sub 3} nanoparticles had better performance than other catalysts from viewpoint of yield and reaction time. The present protocol offers several advantages, such as short reaction time, reasonable yield, mild reaction condition and recycling catalysts with a very easy workup. (author)

  7. Precise tests of low energy QCD from K{sub e4} decay properties

    Energy Technology Data Exchange (ETDEWEB)

    Batley, J.R.; Kalmus, G.; Munday, D.J.; Wotton, S.A. [University of Cambridge, Cavendish Laboratory, Cambridge (United Kingdom); Lazzeroni, C.; Slater, M.W. [University of Cambridge, Cavendish Laboratory, Cambridge (United Kingdom); University of Birmingham, Birmingham (United Kingdom); Arcidiacono, R.; Clemencic, M. [CERN, Geneve 23 (Switzerland); Dipartimento di Fisica Sperimentale dell' Universita e Sezione dell' INFN di Torino, Torino (Italy); Bocquet, G.; Ceccucci, A.; Falaleev, V.; Fidecaro, M.; Gatignon, L.; Gonidec, A.; Kubischta, W.; Maier, A.; Peters, A. [CERN, Geneve 23 (Switzerland); Cabibbo, N. [CERN, Geneve 23 (Switzerland); Universita di Roma ' La Sapienza' e Sezzione dell' INFN di Roma, Roma (Italy); Cundy, D. [CERN, Geneve 23 (Switzerland); Istituto di Cosmogeofisica del CNR di Torino, Torino (Italy); Norton, A.; Fiorini, M. [CERN, Geneve 23 (Switzerland); Dipartimento di Fisica dell' Universita e Sezione dell' INFN di Ferrara, Ferrara (Italy); Patel, M. [CERN, Geneve 23 (Switzerland); Imperial College, Department of Physics, London (United Kingdom); Balev, S.; Hristov, P. [CERN, Geneve 23 (Switzerland); Joint Institute for Nuclear Research, Dubna (Russian Federation); Frabetti, P.L.; Kekelidze, V.; Madigozhin, D.; Molokanova, N.; Polenkevich, I.; Potrebenikov, Yu.; Zinchenko, A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Goudzovski, E. [Joint Institute for Nuclear Research, Dubna (Russian Federation); University of Birmingham, Birmingham (United Kingdom); Kozhuharov, V.; Litov, L. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Univ. of Sofia ' St. Kl. Ohridski' , Faculty of Physics, Sofia (Bulgaria); Marinova, E. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Sezione dell' INFN di Perugia, Perugia (Italy); Stoynev, S. [Joint Inst. for Nuclear Research, Dubna (Russian Federation); Northwestern Univ., Dept. of Physics and Astronomy, Evanston, IL (United States)] (and others)

    2010-12-15

    We report results from the analysis of the K{sup {+-}}{yields}{pi}{sup +}{pi}{sup -}e{sup {+-}}{nu} (K{sub e4}) decay by the NA48/2 collaboration at the CERN SPS, based on the total statistics of 1.13 million decays collected in 2003-2004. The hadronic form factors in the S- and P-wave and their variation with energy are obtained. The phase difference between the S- and P-wave states of the {pi}{pi} system is accurately measured and allows a precise determination of a{sub 0}{sup 0} and a{sub 0}{sup 2}, the I=0 and I=2 S-wave {pi}{pi} scattering lengths: a{sub 0}{sup 0}=0.2220 {+-}0.0128 {sub stat}{+-}0.0050{sub syst}{+-}0.0037{sub th}, a{sub 0}{sup 2}=-0.0432{+-}0.0086{sub stat}{+-}0.0034{sub syst}{+-}0.0028{sub th}. Combination of this result with the other NA48/2 measurement obtained in the study of K{sup {+-}}{yields}{pi}{sup 0}{pi}{sup 0}{pi}{sup {+-}} decays brings an improved determination of a{sub 0}{sup 0} and the first precise experimental measurement of a{sub 0}{sup 2}, providing a stringent test of Chiral Perturbation Theory predictions and lattice QCD calculations. Using constraints based on analyticity and chiral symmetry, even more precise values are obtained: a{sub 0}{sup 0}=0.2196{+-}0.0028{sub stat}{+-}0.0020{sub syst} and a{sub 0}{sup 2}=-0.0444{+-}0.0007{sub stat}{+-}0.0005{sub syst}{+-}0.0008{sub ChPT}. (orig.)

  8. Post-irradiation examinations and high-temperature tests on undoped large-grain UO{sub 2} discs

    Energy Technology Data Exchange (ETDEWEB)

    Noirot, J., E-mail: jean.noirot@cea.fr [CEA, DEN, DEC, Cadarache, F-13108 St. Paul Lez Durance (France); Pontillon, Y. [CEA, DEN, DEC, Cadarache, F-13108 St. Paul Lez Durance (France); Yagnik, S. [EPRI, P.O. Box 10412, Palo Alto, CA 94303-0813 (United States); Turnbull, J.A. [Independent Consultant (United Kingdom)

    2015-07-15

    Within the Nuclear Fuel Industry Research (NFIR) programme, several fuel variants –in the form of thin circular discs – were irradiated in the Halden Boiling Water Reactor (HBWR) at burn-ups up to ∼100 GWd/t{sub HM}. The design of the fuel assembly was similar to that used in other HBWR programmes: the assembly contained several rods with fuel discs sandwiched between Mo discs, which limited temperature differences within each fuel disc. One such variant was made of large-grain UO{sub 2} discs (3D grain size = ∼45 μm) which were subjected to three burn-ups: 42, 72 and 96 GWd/t{sub HM}. Detailed characterizations of some of these irradiated large-grain UO{sub 2} discs were performed in the CEA Cadarache LECA-STAR hot laboratory. The techniques used included electron probe microanalysis (EPMA), scanning electron microscopy (SEM) and secondary ion mass spectrometry (SIMS). Comparisons were then carried out with more standard grain size UO{sub 2} discs irradiated under the same conditions. Examination of the high burn-up large-grain UO{sub 2} discs revealed the limited formation of a high burn-up structure (HBS) when compared with the standard-grain UO{sub 2} discs at similar burn-up. High burn-up discs were submitted to temperature transients up to 1200 °C in the heating test device called Merarg at a relatively low temperature ramp rate (0.2 °C/s). In addition to the total gas release during these tests, the release peaks throughout the temperature ramp were monitored. Tests at 1600 °C were also conducted on the 42 GWd/t{sub HM} discs. The fuels were then characterized with the same microanalysis techniques as those used before the tests, to investigate the effects of these tests on the fuel’s microstructure and on the fission gas behaviour. This paper outlines the high resistance of this fuel to gas precipitation at high temperature and to HBS formation at high burn-up. It also shows the similarity of the positions, within the grains, where HBS forms

  9. Development of a highly efficient conversion electron Moessbauer spectroscopy (CEMS) detector for low temperature (<20 K) measurements and tests on Fe / (Eu{sub x}Pb{sub 1-x})Te bilayers; Desenvolvimento de um detector de alta eficiencia para espectroscopia Moessbauer de eletrons de conversao (CEMS) a baixas temperaturas (<20K) e testes em bicamadas Fe / (Eu{sub x}Pb{sub 1-x})Te

    Energy Technology Data Exchange (ETDEWEB)

    Pombo, Carlos Jose da Silva Matos

    2006-07-01

    The {sup 57}Fe Moessbauer spectroscopy is a nuclear, non-destructive technique used for the investigation of structural, magnetic and hyperfine properties of several materials. It is a powerful tool in characterizing materials in physics, metallurgy, geology and biology field areas, especially magnetic materials, alloys and minerals containing Fe. Lately, the Conversion Electron Moessbauer Spectroscopy (CEMS) is widely used in making studies on ultra-thin magnetic films, as well as other nanostructured materials. In case of magnetic nanostructures, low temperature (LT) studies are especially important due to the possibility of dealing with superparamagnetic effects. In this work it was developed a CEMS measurement system for low temperatures (<20 K) based on a solid-state electron multiplier (Channeltron{sup R}) and an optical cryostat (Model SVT-400, Janis Research Co, USA), from which the project was originally conceived at the Applied Physics / Moessbauer spectroscopy Department from University of Duisburg-Essen, Germany. The LT-CEMS system was fully built, tested and successfully applied in a preliminary characterization of Fe/(Eu{sub x}Pb{sub 1-x})Te(111) bilayers with use of a 15 angstrom, {sup 57} Fe probe layer, with reasonable results at sample temperatures as low as 8 K. (author)

  10. Protonation and structural/chemical stability of Ln{sub 2}NiO{sub 4+δ} ceramics vs. H{sub 2}O/CO{sub 2}: High temperature/water pressure ageing tests

    Energy Technology Data Exchange (ETDEWEB)

    Upasen, S. [Sorbonne Universités, UPMC Univ Paris 06, UMR 8233, MONARIS, 75005 Paris (France); CNRS-IP2CT, UMR 8233, MONARIS, F-75005 Paris (France); Batocchi, P.; Mauvy, F. [ICMCB, ICMCB-CNRS-IUT-Université de Bordeaux, 33608 Pessac Cedex (France); Slodczyk, A. [Sorbonne Universités, UPMC Univ Paris 06, UMR 8233, MONARIS, 75005 Paris (France); CNRS-IP2CT, UMR 8233, MONARIS, F-75005 Paris (France); Colomban, Ph., E-mail: philippe.colomban@upmc.fr [Sorbonne Universités, UPMC Univ Paris 06, UMR 8233, MONARIS, 75005 Paris (France); CNRS-IP2CT, UMR 8233, MONARIS, F-75005 Paris (France)

    2015-02-15

    Highlights: • High temperature/water pressure autoclave is used to study the reaction/corrosion at SOFC/HTSE electrode. • High stability of Pr{sub 2}NiO{sub 4+δ} (PNO) and Nd{sub 2}NiO{sub 4+δ} (NNO) dense ceramics vs. water pressure is demonstrated. • Protonated rare-earth nickelates retain the perovskite-type structure and their H-content is determined. • Very low laser illumination power is required to avoid RE nickelate phase transition. • Nickelates show increasing stability from La to Pr/Nd vs. CO{sub 2}-rich high temperature water vapor. - Abstract: Mixed ionic-electronic conductors (MIEC) such as rare-earth nickelates with a general formula Ln{sub 2}NiO{sub 4+δ} (Ln = La, Pr, Nd) appear as potential for energy production and storage systems: fuel cells, electrolysers and CO{sub 2} converters. Since a good electrode material should exhibit important stability in operating conditions, the structural and chemical stability of different nickelate-based, well-densified ceramics have been studied using various techniques: TGA, dilatometry, XRD, Raman scattering and IR spectroscopy. Consequently, La{sub 2}NiO{sub 4+δ} (LNO), Pr{sub 2}NiO{sub 4+δ} (PNO) and Nd{sub 2}NiO{sub 4+δ} (NNO) have been exposed during 5 days to high water vapor pressure (40 bar) at intermediate temperature (550 °C) in an autoclave device, the used water being almost free or saturated with CO{sub 2}. Such protonation process offers an accelerating stability test and allows the choice of the most pertinent composition for industrial applications requiring a selected material with important life-time. In order to understand any eventual change of crystal structure, the ceramics were investigated in as-prepared, pristine state as well as after protonation and deprotonation (due to thermal treatment till 1000 °C under dry atmosphere). The results show the presence of traces or second phases originating from undesirable hydroxylation and carbonation, detected in the near

  11. Effect of Al doping on structural and magnetic properties of Ni{sub 50}Mn{sub 37}Al{sub x}Sb{sub 13−x} alloy

    Energy Technology Data Exchange (ETDEWEB)

    Ray, Mayukh K.; Bagani, K. [Surface Physics Division, Saha Institute of Nuclear Physics, Kolkata 700064 (India); Singh, R.K.; Majumdar, B. [Defense Metrological Research Laboratory, Hyderabad 500058 (India); Banerjee, S., E-mail: sangam.banerjee@saha.ac.in [Surface Physics Division, Saha Institute of Nuclear Physics, Kolkata 700064 (India)

    2014-09-01

    The Ni{sub 50}Mn{sub 37}Al{sub x}Sb{sub 13−x} (x=0, 1, 3 and 5) alloys were prepared by tri-arc melting technique. The replacement of Sb by Al increases the martensitic transformation temperature (T{sub M}) as well as ferromagnetic to paramagnetic transformation temperature (T{sub C}{sup A}) within the austenite phase. The increase in T{sub M} is found to due to the enhancement of hybridization between 3d states of Ni and Mn atoms. We also observed a large exchange bias field (H{sub EB}) of 470 Oe for x=0 and it decreases with the Al concentration for field cooled (FC) magnetic hysteresis loop. A large magnetic entropy change (ΔS{sub M}) of 10 J/kg-K is found for x=1 alloy under a field change (ΔH) of 50 kOe and it decreased for further higher concentration of Al doping. The possible reasons for observed behaviors are discussed.

  12. Fuel Retrieval Sub-Project (FRS) Stuck Fuel Station Performance Test Data Report

    International Nuclear Information System (INIS)

    THIELGES, J.R.

    2000-01-01

    This document provides the test data report for Stuck Fuel Station Performance Testing in support of the Fuel Retrieval Sub-Project. The stuck fuel station was designed to provide a means of cutting open a canister barrel to release fuel elements, etc

  13. Influence of the pressure and power on the non-equilibrium plasma chemistry of C{sub 2}, C{sub 2}H, C{sub 2}H{sub 2}, CH{sub 3} and CH{sub 4} affecting the synthesis of nanodiamond thin films from C{sub 2}H{sub 2} (1%)/H{sub 2}/Ar-rich plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Gordillo-Vazquez, F J [Instituto de Optica, C.S.I.C., Serrano 121, 28006 Madrid (Spain); Albella, J M [Instituto de Materiales de Madrid, C.S.I.C., Cantoblanco, 28049 Madrid (Spain)

    2004-02-01

    We have used a kinetic model to investigate the influence of changing the pressure (0.1-0.8 Torr) and power (100-300 W) on the non-equilibrium plasma chemistry of RF (13.56 MHz) produced C{sub 2}H{sub 2} (1%)/H{sub 2}/Ar plasmas of interest for the synthesis of nanodiamond thin films. We found that the concentrations of the species C{sub 2}(X{sup 1}SIGMA{sup +}{sub g}), C{sub 2}(a{sup 3}PI{sub u}) and C{sub 2}H are not sensitive to variations in the power but they exhibit a significant increase when the pressure decreases at high argon content in the plasma. In addition, the concentrations of C{sub 2}H{sub 2}, CH{sub 4} and CH{sub 3} exhibit a slight (case of C{sub 2}H{sub 2}) or negligible (case of CH{sub 3} and CH{sub 4}) power-dependence although they decrease (case of C{sub 2}H{sub 2} and CH{sub 4}) or remain almost constant (case of CH{sub 3}) as the pressure decreases. A reasonable agreement is found when comparing the model predictions with available experimental results. These findings provide a basic understanding of the plasma chemistry of hydrocarbon/Ar-rich plasma environments and, at the same time, can be of interest to optimize the processing conditions of nanodiamond films from medium pressure RF hydrocarbon/Ar-rich plasmas.

  14. Improved accuracy in quantitative laser-induced breakdown spectroscopy using sub-models

    Science.gov (United States)

    Anderson, Ryan; Clegg, Samuel M.; Frydenvang, Jens; Wiens, Roger C.; McLennan, Scott M.; Morris, Richard V.; Ehlmann, Bethany L.; Dyar, M. Darby

    2017-01-01

    Accurate quantitative analysis of diverse geologic materials is one of the primary challenges faced by the Laser-Induced Breakdown Spectroscopy (LIBS)-based ChemCam instrument on the Mars Science Laboratory (MSL) rover. The SuperCam instrument on the Mars 2020 rover, as well as other LIBS instruments developed for geochemical analysis on Earth or other planets, will face the same challenge. Consequently, part of the ChemCam science team has focused on the development of improved multivariate analysis calibrations methods. Developing a single regression model capable of accurately determining the composition of very different target materials is difficult because the response of an element’s emission lines in LIBS spectra can vary with the concentration of other elements. We demonstrate a conceptually simple “sub-model” method for improving the accuracy of quantitative LIBS analysis of diverse target materials. The method is based on training several regression models on sets of targets with limited composition ranges and then “blending” these “sub-models” into a single final result. Tests of the sub-model method show improvement in test set root mean squared error of prediction (RMSEP) for almost all cases. The sub-model method, using partial least squares regression (PLS), is being used as part of the current ChemCam quantitative calibration, but the sub-model method is applicable to any multivariate regression method and may yield similar improvements.

  15. Confronting Science: The Dilemma of Genetic Testing.

    Science.gov (United States)

    Zallen, Doris T.

    1997-01-01

    Considers the opportunities and ethical issues involved in genetic testing. Reviews the history of genetics from the first discoveries of Gregor Mendel, through the spurious pseudo-science of eugenics, and up to the discovery of DNA by James Watson and Francis Crick. Explains how genetic tests are done. (MJP)

  16. Subtask 2.18 - Advancing CO<sub>2sub> Capture Technology: Partnership for CO<sub>2sub> Capture (PCO<sub>2sub>C) Phase III

    Energy Technology Data Exchange (ETDEWEB)

    Kay, John; Azenkeng, Alexander; Fiala, Nathan; Jensen, Melanie; Laumb, Jason; Leroux, Kerryanne; McCollor, Donald; Stanislowski, Joshua; Tolbert, Scott; Curran, Tyler

    2016-03-31

    Industries and utilities continue to investigate ways to decrease their carbon footprint. Carbon capture and storage (CCS) can enable existing power generation facilities to meet the current national CO<sub>2sub> reduction goals. The Partnership for CO2 Capture Phase III focused on several important research areas in an effort to find ways to decrease the cost of capture across both precombustion and postcombustion platforms. Two flue gas pretreatment technologies for postcombustion capture, an SO<sub>2sub> reduction scrubbing technology from Cansolv Technologies Inc. and the Tri-Mer filtration technology that combines particulate, NOx, and SO<sub>2sub> control, were evaluated on the Energy & Environmental Research Center’s (EERC’s) pilot-scale test system. Pretreating the flue gas should enable more efficient, and therefore less expensive, CO<sub>2sub> capture. Both technologies were found to be effective in pretreating flue gas prior to CO<sub>2sub> capture. Two new postcombustion capture solvents were tested, one from the Korea Carbon Capture and Sequestration R&D Center (KCRC) and one from CO<sub>2sub> Solutions Incorporated. Both of these solvents showed the ability to capture CO<sub>2sub> while requiring less regeneration energy, which would reduce the cost of capture. Hydrogen separation membranes from Commonwealth Scientific and Industrial Research Organisation were evaluated through precombustion testing. They are composed of vanadium alloy, which is less expensive than the palladium alloys that are typically used. Their performance was comparable to that of other membranes that have been tested at the EERC. Aspen Plus® software was used to model the KCRC and CO<sub>2sub> Solutions solvents and found that they would result in significantly improved overall plant performance. The modeling effort also showed that the parasitic steam load at partial capture of 45% is less than half that of 90% overall capture, indicating savings that

  17. Predictors of HIV Testing among Youth in Sub-Saharan Africa: A Cross-Sectional Study.

    Directory of Open Access Journals (Sweden)

    Ibitola O Asaolu

    Full Text Available In spite of a high prevalence of HIV infection among adolescents and young adults in sub-Saharan Africa, uptake of HIV testing and counseling among youth in the region remains sub-optimal. The objective of this study was to assess factors that influence uptake of HIV testing and counseling among youth aged 15-24 years in sub-Saharan Africa.This study used the Demographic and Health Survey (DHS data from countries that represent four geographic regions of sub-Saharan Africa: Congo (Brazzaville, representing central Africa (DHS 2011-2012; Mozambique, representing southern Africa (DHS 2011; Nigeria, representing western Africa (DHS 2013; and Uganda, representing eastern Africa (DHS 2011. Analyses were restricted to 23,367 male and female respondents aged 15-24 years with complete data on the variables of interest. Chi-square tests and logistic regression models were used to assess predictors of HIV testing. Statistical significance was set at p< 0.01.The analysis revealed that a majority of the respondents were female (78.1% and aged 20-24-years (60.7%. Only a limited proportion of respondents (36.5% had ever tested for HIV and even fewer (25.7% demonstrated comprehensive knowledge of HIV/AIDS. There was a significant association between HIV testing and respondents' gender, age, age at sexual debut, and comprehensive knowledge of HIV in the pooled sample. Older youth (adjusted OR (aOR = 2.19; 99% CI = 1.99-2.40 and those with comprehensive knowledge of HIV (aOR = 1.98; 1.76-2.22 had significantly higher odds of ever being tested for HIV than younger respondents and those with limited HIV/AIDS knowledge respectively. Furthermore, men had lower odds of HIV testing than women (aOR = 0.32; 0.28-0.37.Reaching youth in sub-Saharan Africa for HIV testing continues to be a challenge. Public health programs that seek to increase HIV counseling and testing among youth should pay particular attention to efforts that target high-risk subpopulations of youth

  18. Alkali/TX[sub 2] catalysts for CO/H[sub 2] conversion to C[sub 1]-C[sub 4] alcohols

    Energy Technology Data Exchange (ETDEWEB)

    Klier, K.; Herman, R.G.; Bastian, R.D.; Flanagan, K.L.

    1989-01-01

    Ruthenium disulfide catalysts have been synthesized, tested, and characterized during this period of research. It was observed that both the undoped and Cs-doped RuS[sub 2] catalysts produced alcohols and lower amounts of hydrocarbons from H[sub 2]/CO = 1.0 synthesis gas at temperatures above 300[degree]C. Calcination and catalytic testing resulted in partial reduction of the RuS[sub 2] to Ru[sup o]. Calcination under H[sub 2]S prevented the partial reduction of the RuS[sub 2] catalyst, but subsequent catalytic testing again resulted in the formation of a quantity of Ru[sup o]. A Cs-doped RuS[sub 2] catalyst was prepared, but it might have had too high of a loading of Cs. Upon testing, a lower activity was observed for the doped catalyst compared with the undoped catalyst, but the alcohol selectivity was the same for the two catalysts.

  19. Stabilization/Solidification of radioactive molten salt waste by using xSiO{sub 2}-yAl{sub 2}O{sub 3}-zP{sub 2}O{sub 5} material

    Energy Technology Data Exchange (ETDEWEB)

    Hwan-Seo Park; In-Tae Kim; Yong-Zun Cho; Seong-Won Park; Eung-Ho Kim [Korea Atomic Energy Research Institute: 150 Deokjin-dong, Yuseong, Daejeon, 305-353 (Korea, Republic of)

    2008-07-01

    Molten salt waste generated from the electro metallurgical process to recover uranium and transuranic elements is considered as one of problematic wastes to be difficult to immobilize into a durable for final disposal. As an alternative, this study suggested a new method performed at molten state, where dechlorination was achieved with a new inorganic material containing SiO{sub 2}, Al{sub 2}O{sub 3} and P{sub 2}O{sub 5} (SAP). The SAP as a reactive material to molten salt was prepared by a conventional sol-gel process. The prepared SAPs were reacted with each metal chloride, LiCl, CsCl, SrCl{sub 2} and CeCl{sub 3} at 650 deg. C for 6 hours and also were reacted with simulated salt waste consisting of 90 wt% LiCl, 6.8 wt% CsCl and 3.2 wt% SrCl{sub 2} at different waste loading. All the reactions were carried out in oxidative atmosphere and metal chlorides were effectively converted into stable products under a reasonable reaction ratio.

  20. Young Children's Analogical Reasoning in Science Domains

    Science.gov (United States)

    Haglund, Jesper; Jeppsson, Fredrik; Andersson, Johanna

    2012-01-01

    This exploratory study in a classroom setting investigates first graders' (age 7-8 years, N = 25) ability to perform analogical reasoning and create their own analogies for two irreversible natural phenomena: mixing and heat transfer. We found that the children who contributed actively to a full-class discussion were consistently successful at…

  1. Alkali/TX sub 2 catalysts for CO/H sub 2 conversion to C sub 1 -C sub 4 alcohols

    Energy Technology Data Exchange (ETDEWEB)

    Klier, K.; Herman, R. G.; Bastian, R.

    1990-01-01

    The objective of this research is to investigate and develop novel catalysts for the conversion of coal-derived synthesis gas into C{sub 1}-C{sub 4} alcohols by a highly selective process. Therefore, the variations of catalyst activity and selectivity for the synthesis of alcohols from H{sub 2}/CO {le}1 synthesis gas for a series of A/TX{sub 2} compounds, where A is a surface alkali dopant, T is a transition metal, and X ia a S, Se, or Te, will be determined. This quarter, a fresh batch of MoS{sub 2} was synthesized, and new Cs/MoS{sub 2} catalysts were prepared by alkali doping and were tested to demonstrate that the preparation and testing procedures were reproducible by different personnel. Preparations of RuS{sub 2} and Cs/RuS{sub 2} catalysts were initiated, and the preparations and testing of these catalysts will be described in the next quarterly report. 2 refs., 1 fig., 1 tab.

  2. L(sub 1) Adaptive Control Design for NASA AirSTAR Flight Test Vehicle

    Science.gov (United States)

    Gregory, Irene M.; Cao, Chengyu; Hovakimyan, Naira; Zou, Xiaotian

    2009-01-01

    In this paper we present a new L(sub 1) adaptive control architecture that directly compensates for matched as well as unmatched system uncertainty. To evaluate the L(sub 1) adaptive controller, we take advantage of the flexible research environment with rapid prototyping and testing of control laws in the Airborne Subscale Transport Aircraft Research system at the NASA Langley Research Center. We apply the L(sub 1) adaptive control laws to the subscale turbine powered Generic Transport Model. The presented results are from a full nonlinear simulation of the Generic Transport Model and some preliminary pilot evaluations of the L(sub 1) adaptive control law.

  3. people who inject drugs, HIV risk, and HIV testing uptake in sub-Saharan Africa.

    Science.gov (United States)

    Asher, Alice K; Hahn, Judith A; Couture, Marie-Claude; Maher, Kelsey; Page, Kimberly

    2013-01-01

    Dramatic rises in injection drug use (IDU) in sub-Saharan Africa account for increasingly more infections in a region already overwhelmed by the HIV epidemic. There is no known estimate of the number of people who inject drugs (PWID) in the region, or the associated HIV prevalence in PWID. We reviewed literature with the goal of describing high-risk practices and exposures in PWID in sub-Saharan Africa, as well as current HIV prevention activities aimed at drug use. The literature search looked for articles related to HIV risk, injection drug users, stigma, and HIV testing in sub-Saharan Africa. This review found evidence demonstrating high rates of HIV in IDU populations in sub-Saharan Africa, high-risk behaviors of the populations, lack of knowledge regarding HIV, and low HIV testing uptake. There is an urgent need for action to address IDU in order to maintain recent decreases in the spread of HIV in sub-Saharan Africa. Copyright © 2013 Association of Nurses in AIDS Care. Published by Elsevier Inc. All rights reserved.

  4. Valence behavior of Eu-ions in intermetallic compound Ce{sub 0.5}Eu{sub 0.5}Pd{sub 3}B{sub 0.5}

    Energy Technology Data Exchange (ETDEWEB)

    Pandey, Abhishek, E-mail: apandey@ameslab.gov [Experimental Condensed Matter Physics Division, Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata 700064 (India); S.N. Bose National Centre for Basic Sciences, Block-JD, Sector-III, Salt Lake, Kolkata 700098 (India); Mazumdar, Chandan, E-mail: chandan.mazumdar@saha.ac.in [S.N. Bose National Centre for Basic Sciences, Block-JD, Sector-III, Salt Lake, Kolkata 700098 (India); Ranganathan, R. [S.N. Bose National Centre for Basic Sciences, Block-JD, Sector-III, Salt Lake, Kolkata 700098 (India); Raghavendra Reddy, V.; Gupta, Ajay [UGC-DAE Consortium for Scientific Research, University Campus, Khandawa Road, Indore (India)

    2011-12-15

    We have studied the valence behavior of rare-earth ions, in particular Eu-ions, in a cubic intermetallic compound Ce{sub 0.5}Eu{sub 0.5}Pd{sub 3}B{sub 0.5} which is a homogeneous solid solution of two mixed-valent compounds CePd{sub 3} and EuPd{sub 3}B. Results of {sup 151}Eu Moessbauer spectroscopic measurements show that two different valence states, i.e., divalent- and trivalent-like states of Eu-ions exist in the compound. The possible reason for the observed heterogeneous valency vis-a-vis the variation in the chemical environment and the number of nearest-neighbor B atoms surrounding the Eu-ions has been discussed. Our results demonstrate that B incorporation in such Eu-based cubic intermetallic compounds leads to a situation where heterogeneous-valence state of Eu-ions is an energetically favorable ground state. - Highlights: > Intermetallic compound Ce{sub 0.5}Eu{sub 0.5}Pd{sub 3}B{sub 0.5} crystallizes in a single phase. > Eu-ions in Ce{sub 0.5}Eu{sub 0.5}Pd{sub 3}B{sub 0.5} are charge-ordered compared to +2.3 valency in Ce{sub 0.5}Eu{sub 0.5}Pd{sub 3}. > B incorporation makes charge-ordered state of Eu-ions energetically more favorable. > Nearest-neighbor chemical environment affects the Eu valency.

  5. Neutron diffraction studies of the Na-ion battery electrode materials NaCoCr{sub 2}(PO{sub 4}){sub 3}, NaNiCr{sub 2}(PO{sub 4}){sub 3}, and Na{sub 2}Ni{sub 2}Cr(PO{sub 4}){sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Yahia, H. Ben [Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, P.O. Box 5825 Doha (Qatar); Essehli, R., E-mail: ressehli@qf.org.qa [Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, P.O. Box 5825 Doha (Qatar); Avdeev, M. [Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights NSW 2234 (Australia); Park, J-B.; Sun, Y-K. [Department of Energy Engineering Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of); Al-Maadeed, M.A. [Center for Advanced Materials (CAM), Qatar University, 2713 Doha (Qatar); Belharouak, I., E-mail: ibelharouak@qf.org.qa [Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, P.O. Box 5825 Doha (Qatar)

    2016-06-15

    The new compounds NaCoCr{sub 2}(PO{sub 4}){sub 3}, NaNiCr{sub 2}(PO{sub 4}){sub 3}, and Na{sub 2}Ni{sub 2}Cr(PO{sub 4}){sub 3} were synthesized by sol-gel method and their crystal structures were determined by using neutron powder diffraction data. These compounds were characterized by galvanometric cycling and cyclic voltammetry. NaCoCr{sub 2}(PO{sub 4}){sub 3}, NaNiCr{sub 2}(PO{sub 4}){sub 3}, and Na{sub 2}Ni{sub 2}Cr(PO{sub 4}){sub 3} crystallize with a stuffed α-CrPO{sub 4}-type structure. The structure consists of a 3D-framework made of octahedra and tetrahedra that are sharing corners and/or edges generating channels along [100] and [010], in which the sodium atoms are located. Of significance, in the structures of NaNiCr{sub 2}(PO{sub 4}){sub 3}, and Na{sub 2}Ni{sub 2}Cr(PO{sub 4}){sub 3} a statistical disorder Ni{sup 2+}/Cr{sup 3+} was observed on both the 8g and 4a atomic positions, whereas in NaCoCr{sub 2}(PO{sub 4}){sub 3} the statistical disorder Co{sup 2+}/Cr{sup 3+} was only observed on the 8g atomic position. When tested as negative electrode materials, NaCoCr{sub 2}(PO{sub 4}){sub 3}, NaNiCr{sub 2}(PO{sub 4}){sub 3}, and Na{sub 2}Ni{sub 2}Cr(PO{sub 4}){sub 3} delivered specific capacities of 352, 385, and 368 mA h g{sup −1}, respectively, which attests to the electrochemical activity of sodium in these compounds. - Highlights: • NaCoCr{sub 2}(PO{sub 4}){sub 3}, NaNiCr{sub 2}(PO{sub 4}){sub 3}, and Na{sub 2}Ni{sub 2}Cr(PO{sub 4}){sub 3} were synthesized by sol-gel method. • The crystal structures were determined by using neutron powder diffraction data. • The three compounds crystallize with a stuffed α-CrPO{sub 4}-type structure. • The three compounds were tested as anodes in sodium-ion batteries. • Relatively high specific capacities were obtained for these compounds.

  6. Explanatory item response modeling of children's change on a dynamic test of analogical reasoning

    NARCIS (Netherlands)

    Stevenson, C.E.; Hickendorff, M.; Resing, W.C.M.; Heiser, W.J.; de Boeck, P.A.L.

    Dynamic testing is an assessment method in which training is incorporated into the procedure with the aim of gauging cognitive potential. Large individual differences are present in children's ability to profit from training in analogical reasoning. The aim of this experiment was to investigate

  7. Fabrication of a direct Z-scheme type WO{sub 3}/Ag{sub 3}PO{sub 4} composite photocatalyst with enhanced visible-light photocatalytic performances

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Jinsuo, E-mail: lujinsuo@xauat.edu.cn [School of Environmental and Municipal Engineering, Xi’an University of Architecture and Technology, Xi’an 710055 (China); Wang, Yujing [School of Materials and Chemical Engineering, Xi’an Technological University, Xi’an, Shaanxi 710032 (China); Liu, Fei [School of Environmental and Municipal Engineering, Xi’an University of Architecture and Technology, Xi’an 710055 (China); Zhang, Liang [College of Sciences, Xi’an University of Architecture and Technology, Xi’an 710055 (China); Chai, Shouning, E-mail: s.n.chai@xauat.edu.cn [College of Sciences, Xi’an University of Architecture and Technology, Xi’an 710055 (China)

    2017-01-30

    Highlights: • A solid direct Z-scheme type photocatalyst WO{sub 3}/Ag{sub 3}PO{sub 4} was synthesized. • The WO{sub 3}/Ag{sub 3}PO{sub 4} composite showed enhanced photocatalytic activity and stability. • Nearly complete removal of organic dyes was achieved in a short time. • The reasonable Z-scheme mechanism of WO{sub 3}/Ag{sub 3}PO{sub 4} composite was proposed. - Abstract: A direct Z-scheme type photocatalyst WO{sub 3}/Ag{sub 3}PO{sub 4} composite (molar ration 1:1, 1W/1Ag) was prepared by hydrothermal method. The 1W/1Ag was characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), UV–vis diffuse reflection spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), and photoluminescence emission spectroscopy (PL) etc. technologies. The photocatalytic performances were evaluated by degradation of methylene blue (MB) and methyl orange (MO), and their removal rates were up to 95% after 60 min and 90% after 180 min, respectively. The prepared 1W/1Ag exhibits a much higher photocatalytic activity than pure Ag{sub 3}PO{sub 4} and pure WO{sub 3} under visible light irradiation. The apparent rate constants of MB and MO degradation on 1W/1Ag are about 2.4 and 2.5 times that of pure Ag{sub 3}PO{sub 4}, respectively. The enhanced performance of the 1W/1Ag is attributed to a synergistic effect including relatively high surface area, strong light absorption, matched energy band structure, and the improved separation of photogenerated charge carriers between the two components. A reasonable Z-scheme mechanism referring to directed migration of photoinduced carriers was proposed. Thus, it can be suggested that the 1W/1Ag can serve as a promising photocatalyst for environmental purification and clean energy utilization.

  8. Optimizing Blue Persistent Luminescence in (Sr <sub>1-δsub> Ba <sub>δ> ) <sub>2sub> MgSi <sub>2sub> O <sub>7:sub> Eu 2+ ,Dy 3+ via Solid Solution for Use in Point-of-Care Diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Finley, Erin; Cobb, Angelica; Duke, Anna; Paterson, Andrew; Brgoch, Jakoah (Luminostics); (Houston)

    2016-11-04

    Inorganic persistent luminescent phosphors are an excellent class of optical reporters for enabling sensitive point-of-care diagnostics, particularly with smartphone-based biosensing devices in testing formats such as the lateral flow assay (LFA). Here, the development of persistent phosphors for this application is focused on the solid solution (Sr<sub>1-δsub>Baδ)>2sub>MgSi>2sub>O>7sub>:Eu2+,Dy3+ (δ = 0, 0.125, 0.25, 0.375), which is prepared using a high-temperature solid-state reaction as confirmed by synchrotron X-ray powder diffraction. The substitution of barium for strontium enables control over the Eu2+ 5d-orbital crystal field splitting (CFS) as a tool for tuning the emission wavelength while maintaining luminescence lifetimes >9 min across the composition range. Thermoluminescence measurements of the solid solution provide evidence that trap states contribute to the persistent lifetimes with the trap depths also remaining constant as a function of composition. Time-gated luminescence images of these compounds are captured on a smartphone arranged in a layout to mimic a point-of-care test and demonstrate the viability of using these materials as optical reporters. Moreover, comparing the blue-emitting (Sr<sub>0.625sub>Ba>0.375sub>)>2sub>MgSi>2sub>O>7sub>:Eu2+,Dy3+ and the green-emitting SrAl<sub>2sub>O>4:sub>Eu2+,Dy3+ in a single LFA-type format shows these two compounds can be detected and resolved simultaneously, thereby permitting the development of a multiplexed LFA.

  9. Recent advances with quiescent power supply current (I(sub DDQ)) testing at Sandia using the HP82000

    Science.gov (United States)

    Righter, A. W.; Leong, D. J.; Cox, L. B.

    Last year at the HP82000 Users Group Meeting, Sandia National Laboratories gave a presentation on I(sub DDQ) testing. This year, some advances are presented on this testing including DUT board fixturing, external DC PMU measurement, and automatic IDD-All circuit calibration. Implementation is examined more than theory, with results presented from Sandia tests. After a brief summary I(sub DDQ) theory and testing concepts, how the break (hold state) vector and data formatting present a test vector generation concern for the HP82000 is described. Fixturing of the DUT board for both types of I(sub DDQ) measurement is then discussed, along with how the continuity test and test vector generation must be taken into account. Results of a test including continuity, IDD-All and I(sub DDQ) Value measurements is shown. Next, measurement of low current using an external PMU is discussed, including noise considerations, implementation and some test results showing nA-range measurements. A method is presented for automatic calibration of the IDD-All analog comparator circuit using RM BASIC on the HP82000, with implementation and measurement results. Finally, future directions for research in this area is explored.

  10. Continuous bench-scale slurry catalyst testing direct coal liquefaction rawhide sub-bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Bauman, R.F.; Coless, L.A.; Davis, S.M. [and others

    1995-12-31

    In 1992, the Department of Energy (DOE) sponsored research to demonstrate a dispersed catalyst system using a combination of molybdenum and iron precursors for direct coal liquefaction. This dispersed catalyst system was successfully demonstrated using Black Thunder sub-bituminous coal at Wilsonville, Alabama by Southern Electric International, Inc. The DOE sponsored research continues at Exxon Research and Development Laboratories (ERDL). A six month continuous bench-scale program using ERDL`s Recycle Coal Liquefaction Unit (RCLU) is planned, three months in 1994 and three months in 1995. The initial conditions in RCLU reflect experience gained from the Wilsonville facility in their Test Run 263. Rawhide sub-bituminous coal which is similar to the Black Thunder coal tested at Wilsonville was used as the feed coal. A slate of five dispersed catalysts for direct coal liquefaction of Rawhide sub-bituminous coal has been tested. Throughout the experiments, the molybdenum addition rate was held constant at 100 wppm while the iron oxide addition rate was varied from 0.25 to 1.0 weight percent (dry coal basis). This report covers the 1994 operations and accomplishments.

  11. University Programme Preferences of High School Science Students in Singapore and Reasons that Matter in their Preferences: A Rasch analysis

    Science.gov (United States)

    Oon, Pey-Tee; Subramaniam, R.

    2015-01-01

    This study explored an under-researched area in science education-the university programmes preferred by high school students who take physical science subjects and the reasons that matter in their preferences. A total of 1,071 upper secondary and pre-university students in Singapore, who take physical science subjects among their range of subjects, participated in this study. A survey method was adopted and the Rasch model was used to analyse the data. Overall, Business Studies was ranked as the predominant choice; nonetheless, scientific programmes such as Science, Engineering, and Mathematics are generally still well liked by the students. When gender differences were examined, we found that students largely followed gender-typical programme preferences, in which males tend to incline towards Engineering while females tend to incline towards Arts and Social Sciences. Students prefer a university programme based on their individual interest and ability, with career aspiration and remuneration coming next. Interestingly, females place greater emphasis on career aspiration than males. Some implications of the study are discussed.

  12. Yo-Yo IR2 testing of elite and sub-elite soccer players

    DEFF Research Database (Denmark)

    Ingebrigtsen, Jørgen; Bendiksen, Mads; Randers, Morten Bredsgaard

    2012-01-01

    Abstract We examined performance, heart rate response and construct validity of the Yo-Yo IR2 test by testing 111 elite and 92 sub-elite soccer players from Norway and Denmark. VO(2)max, Yo-Yo IR1 and repeated sprint tests (RSA) (n = 51) and match-analyses (n = 39) were also performed. Yo-Yo IR2...

  13. Fidelity of test development process within a national science grant

    Science.gov (United States)

    Brumfield, Teresa E.

    In 2002, a math-science partnership (MSP) program was initiated by a national science grant. The purpose of the MSP program was to promote the development, implementation, and sustainability of promising partnerships among institutions of higher education, K-12 schools and school systems, as well as other important stakeholders. One of the funded projects included a teacher-scientist collaborative that instituted a professional development system to prepare teachers to use inquiry-based instructional modules. The MSP program mandated evaluations of its funded projects. One of the teacher-scientist collaborative project's outcomes specifically focused on teacher and student science content and process skills. In order to provide annual evidence of progress and to measure the impact of the project's efforts, and because no appropriate science tests were available to measure improvements in content knowledge of participating teachers and their students, the project contracted for the development of science tests. This dissertation focused on the process of test development within an evaluation and examined planned (i.e., expected) and actual (i.e., observed) test development, specifically concentrating on the factors that affected the actual test development process. Planned test development was defined as the process of creating tests according to the well-established test development procedures recommended by the AERA/APA/NCME 1999 Standards for Educational and Psychological Testing. Actual test development was defined as the process of creating tests as it actually took place. Because case study provides an in-depth, longitudinal examination of an event (i.e., case) in a naturalistic setting, it was selected as the appropriate methodology to examine the difference between planned and actual test development. The case (or unit of analysis) was the test development task, a task that was bounded by the context in which it occurred---and over which this researcher had

  14. Improved flux-pinning properties of REBa{sub 2}Cu{sub 3}O{sub 7-z} films by low-level Co doping

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wentao; Pu, Minghua; Wang, Weiwei; Lei, Ming [Key Laboratory of Magnetic Levitation and Maglev Trains, Ministry of Education of China, Superconductivity R and D Centre (SRDC), Southwest Jiaotong University, Erhuanlu Beiyiduan 111, 610031 Chengdu (China); Cheng, Cuihua [Superconductivity Research Group, School of Materials Science and Engineering, University of New South Wales, 2052 NSW, Sydney (Australia); Zhao, Yong [Key Laboratory of Magnetic Levitation and Maglev Trains, Ministry of Education of China, Superconductivity R and D Centre (SRDC), Southwest Jiaotong University, Erhuanlu Beiyiduan 111, 610031 Chengdu (China); Superconductivity Research Group, School of Materials Science and Engineering, University of New South Wales, 2052 NSW, Sydney (Australia)

    2011-09-15

    Biaxially textured REBa{sub 2}Cu{sub 3-x}Co{sub x}O{sub 7-z} (RE = Gd,Y) films were prepared on (00l) LaAlO{sub 3} substrate using self-developed fluorine-free chemical solution deposition (CSD) approach. The in-field J{sub c} values are significantly improved for REBa{sub 2}Cu{sub 3-x}Co{sub x}O{sub 7-z} films through low-level Co doping. Co-doped GdBa{sub 2}Cu{sub 3}O{sub 7-z} film shows the highest J{sub c} values at higher temperatures and fields, whereas the J{sub c} values of Co-doped YBa{sub 2}Cu{sub 3}O{sub 7-z} film surpass that of other films at lower temperatures and fields. In addition, the volume pinning force densities of films with Co doping have been distinctly enhanced in the applied fields, indicating improved flux-pinning properties. The possible reasons are discussed in detail. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  15. Science Library of Test Items. Volume Three. Mastery Testing Programme. Introduction and Manual.

    Science.gov (United States)

    New South Wales Dept. of Education, Sydney (Australia).

    A set of short tests aimed at measuring student mastery of specific skills in the natural sciences are presented with a description of the mastery program's purposes, development, and methods. Mastery learning, criterion-referenced testing, and the scope of skills to be tested are defined. Each of the multiple choice tests for grades 7 through 10…

  16. Foundations of the Formal Sciences VI: Probabilistic reasoning and reasoning with probabilities

    NARCIS (Netherlands)

    Löwe, B.; Pacuit, E.; Romeijn, J.W.

    2009-01-01

    Probabilistic methods are increasingly becoming an important tool in a variety of disciplines including computer science, mathematics, artificial intelligence, epistemology, game and decision theory and linguistics. In addition to the discussion on applications of probabilistic methods there is an

  17. Single crystal Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8} structures as THz-emitters

    Energy Technology Data Exchange (ETDEWEB)

    Wieland, Raphael; Rudau, Fabian; Langer, Julian; Koelle, Dieter; Kleiner, Reinhold [Physikalisches Institut and Center for Collective Quantum Phenomena in LISA+, Universitaet Tuebingen, Tuebingen (Germany); Kinev, Nickolay; Koshelets, Valery [Kotel' nikov Institute of Radio Engineering and Electronics, Moscow (Russian Federation); Yuan, Jie; Ishii, Akira; Hatano, Takeshi [National Institute for Materials Science, Tsukuba (Japan); Huang, Ya; Ji, Min; Zhou, Xianjing; Wang, Huabing [National Institute for Materials Science, Tsukuba (Japan); Research Institute of Superconductor Electronics, Nanjing University, Nanjing (China); Wu, Peiheng [Research Institute of Superconductor Electronics, Nanjing University, Nanjing (China)

    2016-07-01

    By means of Josephson Junctions (JJs) one can easily convert a dc voltage into high-frequency electromagnetic radiation. The high-Tc superconductor Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8} (BSCCO) has a layered crystal structure in such a way that JJs form intrinsically. This allows to fabricate hundreds of stacked junctions with reasonable effort. Terahertz emission can be observed at relatively low bias currents but also at higher input power. Emission frequencies from 0.4 to 2.4 THz have been measured. A hot spot forms at high bias currents with effect on both intensity and linewidth of the THz emission.BSCCO mesas probably act as a cavity for electromagnetic standing waves that synchronize all junctions in the stack. We investigated hotspot formation and THz emission using a combination of transport measurements, low temperature scanning laser microscopy and electromagnetic wave detection via a superconducting receiver.

  18. Analysis of ({sup 7}F{sub 0}){gamma}{sub 1g}{yields}({sup 5}D{sub 2}){gamma}{sub 5g}, {gamma}{sub 3g} and ({sup 7}F{sub 0}){gamma}{sub 1g}{yields}({sup 5}L{sub 6}){gamma}{sub 1g}, a{gamma}{sub 5g} two-photon absorption spectra of Cs{sub 2}NaYF{sub 6}:Eu{sup 3+}

    Energy Technology Data Exchange (ETDEWEB)

    Ning Lixin; Wang Dianyuan; Xia Shangda [Structure Research Laboratory, Academica Sinica, Department of Physics, University of Science and Technology of China, Heifei, Anhui (China); Thorne, Jonathan R.G. [Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford (United Kingdom); Tanner, Peter A. [Department of Biology and Chemistry, City University of Hong Kong, Kowloon (China)

    2002-04-15

    The direct calculation of transition line strengths and relative intensities is presented for two intraconfigurational two-photon absorption (TPA) transitions of Eu{sup 3+} in the cubic Cs{sub 2}NaYF{sub 6} host. Crystal field wavefunctions were utilized for the initial and final f{sup N}-electron states and various approaches were used in constructing all the 4f{sup N-1} 5d{sup 1} intermediate-state wavefunctions. The calculated relative intensities of the ({sup 7}F{sub 0}) {gamma}{sub 1g}{yields}({sup 5}D{sub 2}){gamma}{sub 5g}, {gamma}{sub 3g} TPA transitions are in reasonable agreement with experiment. The neglect of J-mixing in the initial state has only a small effect upon the calculation, whereas the neglect of spin-orbit couplings within the initial and terminal states drastically reduces the calculated transition linestrengths, but does not markedly change the intensity ratios. In the case of the ({sup 7}F{sub 0}){gamma}{sub 1g}{yields}({sup 5}L{sub 6}){gamma}{sub 1g}, a{gamma}{sub 5g} transitions, serious discrepancies between experiment and theory are found if the intermediate states are constructed from a 4f{sup 5} core comprising free ion states and the 5d{sup 1} crystal field states. Satisfactory agreement is, however, found when the 4f{sup 5} crystal field states are utilized in constructing the intermediate states. The contributions to the transition moment have been evaluated for various Hamiltonian terms and the results are discussed. (author)

  19. Test-enhanced learning: the potential for testing to promote greater learning in undergraduate science courses.

    Science.gov (United States)

    Brame, Cynthia J; Biel, Rachel

    2015-01-01

    Testing within the science classroom is commonly used for both formative and summative assessment purposes to let the student and the instructor gauge progress toward learning goals. Research within cognitive science suggests, however, that testing can also be a learning event. We present summaries of studies that suggest that repeated retrieval can enhance long-term learning in a laboratory setting; various testing formats can promote learning; feedback enhances the benefits of testing; testing can potentiate further study; and benefits of testing are not limited to rote memory. Most of these studies were performed in a laboratory environment, so we also present summaries of experiments suggesting that the benefits of testing can extend to the classroom. Finally, we suggest opportunities that these observations raise for the classroom and for further research. © 2015 C. J. Brame and R. Biel. CBE—Life Sciences Education © 2015 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  20. Crystallization of Zr<sub>2sub>PdxCu>1-xsub> and Zr<sub>2sub>NixCu>1-xsub> Metallic Glass

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Min [Iowa State Univ., Ames, IA (United States)

    2008-01-01

    One interesting aspect of rretallic glasses is the numerous instances of the deviation of the phase selection from the amorphous state to thermodynamically stable phases during the crystallization process. Their devitrification pathways allow us to study the relationship between the original amorphous structure and their crystalline counter parts. Among the various factors of phase selections, size and electronic effects have been most extensively studied. Elucidating the phase selection process of a glassy alloy will be helpful to fill in the puzzle of the changes from disordered to ordered structures. In this thesis, Two model Zr<sub>2sub>PdxCu>1-xsub> and Zr<sub>2sub>NixCu>1-xsub> (x = 0, 0.25, 0.5, 0.75 and 1) glassy systems were investigated since: (1) All of the samples can be made into a homogenous metallic glass; (2) The atomic radii differ from Pd to Cu is by 11%, while Ni has nearly the identical atomic size compare to Cu. Moreover, Pd and Ni differ by only one valence electron from Cu. Thus, these systems are ideal to test the idea of the effects of electronic structure and size factors; (3) The small number of components in these pseudo binary systems readily lend themselves to theoretical modeling. Using high temperature X-ray diffraction (HTXRD) and thermal analysis, topological, size, electronic, bond and chemical distribution factors on crystallization selections in Zr<sub>2sub>PdxCu>1-xsub> and Zr<sub>2sub>NixCu>1-xsub> metallic glass have been explored. All Zr<sub>2sub>PdxCu>1-xsub> compositions share the same Cu11b phase with different pathways of meta-stable, icosahedral quasicrystalline phase (i-phase), and C16 phase formations. The quasicrystal phase formation is topologically related to the increasing icosahedral short range order (SRO) with Pd content in Zr<sub>2sub>PdxCu>1-xsub> system. Meta-stable C16 phase is competitive with

  1. Quaternary equilibrium diagrams ZrO{sub 2}-Al{sub 2}O{sub 3}-SiO{sub 2}-(CaO, MgO, TiO{sub 2}). A powerful tool for the development of new materials by reaction sintering; Diagramas de equilibrio cuaternarios ZrO{sub 2}-Al{sub 2}O{sub 3}-SiO{sub 2}- (CaO, MgO, TiO{sub 2}). Una poderosa herramienta para el desarrollo de nuevos materiales por sinterizacion reactiva

    Energy Technology Data Exchange (ETDEWEB)

    Moya, J. S.; Bartolome, J. F.; Pena, P.

    2011-07-01

    In this paper we set out, discuss and evaluate the work on Mullite-zirconia composites obtained by reaction sintering led and inspired by Salvador de Aza on the basis of ZrO{sub 2}-Al{sub 2}O{sub 3}-SiO{sub 2}-(CaO, MgO, TiO{sub 2}) multicomponent phase equilibrium diagrams. We analyze their impact on different areas of ceramic science and technology such as refractory grogs, aluminum industry, etc. The possible fields of future applications such as dental prosthesis replacing partially stabilized zirconia materials with rare earths are also reported. (Author) 42 refs.

  2. Science Library of Test Items. Volume Nine. Mastery Testing Programme. [Mastery Tests Series 1.] Tests M1-M13.

    Science.gov (United States)

    New South Wales Dept. of Education, Sydney (Australia).

    As part of a series of tests to measure mastery of specific skills in the natural sciences, copies of the first 13 tests are provided. Skills to be tested include: (1) reading a table; (2) using a biological key; (3) identifying chemical symbols; (4) identifying parts of a human body; (5) reading a line graph; (6) identifying electronic and…

  3. Reasoning robots the art and science of programming robotic agents

    CERN Document Server

    Thielscher, Michael

    2005-01-01

    The book provides an in-depth and uniform treatment of a mathematical model for reasoning robotic agents. The book also contains an introduction to a programming method and system based on this model. The mathematical model, known as the "Fluent Calculus,'' describes how to use classical first-order logic to set up symbolic models of dynamic worlds and to represent knowledge of actions and their effects. Robotic agents use this knowledge and their reasoning facilities to make decisions when following high-level, long-term strategies. The book covers the issues of reasoning about sensor input, acting under incomplete knowledge and uncertainty, planning, intelligent troubleshooting, and many other topics. The mathematical model is supplemented by a programming method which allows readers to design their own reasoning robotic agents. The usage of this method, called "FLUX,'' is illustrated by many example programs. The book includes the details of an implementation of FLUX using the standard programming language...

  4. Donut-shaped Co{sub 3}O{sub 4} nanoflakes grown on nickel foam with enhanced supercapacitive performances

    Energy Technology Data Exchange (ETDEWEB)

    Han, Zhicheng; Zheng, Xin; Yao, Shunyu; Xiao, Huanhao; Qu, Fengyu; Wu, Xiang, E-mail: wuxiang05@163.com

    2016-03-01

    Graphical abstract: The as-synthesized product exhibits a high initial discharge capacitance of 518 mF/cm{sup 2} at a current density of 1 mA cm{sup −2} and can maintain 75% capacitance retention even after 6000 charge–discharge cycles. Electrochemical results revealed that the prepared Co{sub 3}O{sub 4} nanoflakes possess a remarkable performance in supercapacitor applications. - Highlights: • Donut-shaped Co{sub 3}O{sub 4} nanoflakes were first fabricated by a solution approach. • The tests show high discharge areal capacitance and long cycle life stability. • Co{sub 3}O{sub 4} nanoflakes might be promising supercapacitor electrode materials. - Abstract: Donut-shaped Co{sub 3}O{sub 4} nanoflakes grown on nickel foam were successfully fabricated by a simple one-pot hydrothermal approach. The prepared products were functionalized as the supercapacitors electrodes. Electrochemical performance of the as-prepared products demonstrated high specific capacitance (518 mF cm{sup −2}) and excellent cycling stability (∼25% loss) after 6000 repetitive cycles at a charge–discharge current density of 1 mA cm{sup −2}. The superior electrochemical performance may be ascribed into two reasons: one is the unique spatial structures which possess many active sites and provide enhanced combination between the electrode and nickel foam to support fast ion and electron transfer, the other is that donut-shaped Co{sub 3}O{sub 4} nanoflakes electrodes show relatively lower resistances. It is expected that the as-obtained donut-shaped Co{sub 3}O{sub 4} nanoflakes could have potential applications in portable electronics and electrical vehicles.

  5. Operation Test of the Supercritical CO{sub 2} Compressor Supported with Active Magnetic Bearing

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Jae Eun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Cho, Seong Kuk; Lee, Jeong IK [KAIST, Daejeon (Korea, Republic of)

    2016-10-15

    In this paper, the operation test status of the SCIEL sCO{sub 2} AMB Compressor is briefly described. The Supercritical CO{sub 2} Brayton Cycle Integral Experiment Loop (SCIEL) has been installed in Korea Atomic Energy Research Institute (KAERI) to develop the element technologies for the sCO{sub 2} cycle power generation system. The operation of the SCIEL has mainly focused on sCO{sub 2} compressor development and establishing sCO{sub 2} system control logic. The installation of the SCIEL low compression loop was finished in December 2014 and research team succeeded in generating electric power on the supercritical state of the CO{sub 2} in May 2015. The SCIEL has been built in KAERI to develop the element technologies and the system control logics for the sCO{sub 2} cycle power conversion unit of the next generation reactor. For the stable operation of the sCO{sub 2} compressor under high rotational speed, the AMB sCO{sub 2} compressor was developed and achieved the maximum 40,000 rpm.

  6. Pedagogy of Science Teaching Tests: Formative assessments of science teaching orientations

    Science.gov (United States)

    Cobern, William W.; Schuster, David; Adams, Betty; Skjold, Brandy Ann; Zeynep Muğaloğlu, Ebru; Bentz, Amy; Sparks, Kelly

    2014-09-01

    A critical aspect of teacher education is gaining pedagogical content knowledge of how to teach science for conceptual understanding. Given the time limitations of college methods courses, it is difficult to touch on more than a fraction of the science topics potentially taught across grades K-8, particularly in the context of relevant pedagogies. This research and development work centers on constructing a formative assessment resource to help expose pre-service teachers to a greater number of science topics within teaching episodes using various modes of instruction. To this end, 100 problem-based, science pedagogy assessment items were developed via expert group discussions and pilot testing. Each item contains a classroom vignette followed by response choices carefully crafted to include four basic pedagogies (didactic direct, active direct, guided inquiry, and open inquiry). The brief but numerous items allow a substantial increase in the number of science topics that pre-service students may consider. The intention is that students and teachers will be able to share and discuss particular responses to individual items, or else record their responses to collections of items and thereby create a snapshot profile of their teaching orientations. Subsets of items were piloted with students in pre-service science methods courses, and the quantitative results of student responses were spread sufficiently to suggest that the items can be effective for their intended purpose.

  7. Mathematical Description and Mechanistic Reasoning: A Pathway toward STEM Integration

    Science.gov (United States)

    Weinberg, Paul J.

    2017-01-01

    Because reasoning about mechanism is critical to disciplined inquiry in science, technology, engineering, and mathematics (STEM) domains, this study focuses on ways to support the development of this form of reasoning. This study attends to how mechanistic reasoning is constituted through mathematical description. This study draws upon Smith's…

  8. LiCl+CaCl/sub 2//H/sub 2/O pair

    Energy Technology Data Exchange (ETDEWEB)

    Isshiki, N; Kamoshida, J

    1985-01-01

    Absorption heat pump is very useful for the utilization of new energy of low temperature difference by the following four view points. (a) possibility of using any kind of heat source of low temperature difference natural energy and industrial waste heat. (b) Possibility of being used for either of both generation of heat and power (co-generation), (c) good for long term storage and distance transportation of energy. (d) Possibility of applying any kind of chemical pair which have reversible thermo-chemical reaction with a lot of varieties. Among many thermo-chemical pairs, the pair of LiCl + CaCl/sub 2//H/sub 2/O has been selected and investigated in the R and D of developing power generation system. The reason of this selection is that this pair have been thought to be most practical, inexpensive, and powerful for our purpose. The system of heat and power cogeneration system has been selected as the object of application of the absorption system, and especially power generation has been studied. Then, in order to inquire the possibility of power generation and energy storage, a four wheeled vehicle driven by the power of the pair of L1Cl = CaCl/sub 2//H/sub 2/O has been assembled and tested with success. In this paper the general aspects of this study is reported briefly, and the future possibility of the absorption heat pump and power generation is discussed.

  9. Final Research Performance Report - Small Molecular Associative Carbon Dioxide (CO<sub>2sub>) Thickeners for Improved Mobility Control

    Energy Technology Data Exchange (ETDEWEB)

    Enick, Robert M. [Univ. of Pittsburgh, PA (United States)

    2017-12-31

    dissolved in the CO<sub>2sub>2. Our team also planned thickener concentrations and compositions at Pitt for the core tests that were conducted at Special Core Analysis Laboratories, Inc., (SCAL) in Midland, TX, where the ability for PFA to reduce CO<sub>2sub> mobility in a core was then tested. During the beginning of these tests, the PFA polymer was then shown to impart reasonable improvements in mobility control during the SCAL core tests; as the CO<sub>2sub>-PFA solution displaced CO<sub>2sub> from the core at a constant volumetric flow rate, the pressure drop increased as expected. However, as the test progressed, there was clear and surprising evidence of dramatic reductions in core permeability due to PFA adsorption, especially for sandstones. For example, as the CO<sub>2sub>-PFA solution displaced pure CO<sub>2sub> from sandstone and limestone cores, the pressure drop increased by factors of multiple hundreds to over a thousand. It was subsequently demonstrated that the PFA injected into the core either (a) adsorbed strongly and irreversibly onto the rock surfaces, (b) deposited/precipitated within the rock, thereby blocking pores in a manner that could be dislodged by large changes in flow rate or flow direction, or (c) remained in solution and passed completely through the core. The loss of PFA to the porous media and the unacceptably large increases in pressure drop both indicated that PFA was inappropriate for CO<sub>2sub> EOR mobility control, where thickener adsorption must be minimized and mobility reductions of only 10-100-fold are typically required. However, we realized that because the CO<sub>2sub>-PFA solution could greatly reduce the permeability of porous media, it could serve as a near wellbore conformance control agent for blocking “thief zones”, where adsorption is acceptable and dramatic increases in pressure drop are desirable. These effects were more dramatic for sandstone than for limestone. Therefore, these PFA fluoroacrylate

  10. Structure of the new Tl(Ba sub 1.0 Sr sub 1.0) PrCu sub 2 O sub 7-x by Rietveld analysis

    International Nuclear Information System (INIS)

    Yang, P.; Fun, H. K.; Lee, T.J.; Ku, H.C.; Lai, C.C.

    1994-01-01

    The crystalline structure of Tl(Ba sub 1.0 Sr sub 1.0)PrCu sub 2 O sub 7-x was obtained at room temperature from x-ray powder diffraction with CuK sub α radiation using Rietveld analysis. Tl(Ba sub 1.0 Sr sub 1.0)PrCu sub 2 O sub 7-x isomorphous at both room temperature (300 K) and low temperature (100 K) with TlBa sub 2 ca Cu sub 2 O sub 7-x type (1212) structure, crystallized with space group P4/mmm and one formula in the unit cell. At 300 K, cell parameters a=3.8892(2) A, c=12.3099(6) A, the structure was refined with 25 parameters to R sub WP = 6.30%, R sub P = 4.38% for 3551 step intensities and R sub b = 5.01%, R sub f = 4.20% for 156 reflections. The goodness of fitting S=3.18. At 100K, cell parameters a=3.8866(4) A, c= 12.289(1) A, the structure was refined with 26 parameters to R sub WP = 8.42%, R sub P = 6.21% for 2676 step intensities and R sub b = 6.72%, R sub f = 5.28% for 120 reflections. The goodness of fitting S=2.32. Reasonable anisotropic thermal parameters were obtained. The compositions of Ba and Sr atoms were refined to about Ba sub 1.1 Sr sub 0.9 compared with the stoichiometric Ba sub 1.0 Sr sub 1.0

  11. AmO<sub>2sub> Analysis for Analytical Method Testing and Assessment: Analysis Support for AmO<sub>2sub> Production

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, Kevin John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bland, Galey Jean [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Fulwyler, James Brent [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Garduno, Katherine [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Keller, Russell C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Klundt, Dylan James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lujan, Elmer J. W [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mark, Zoe Francoise Elise [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mathew, Kattathu Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ortega, Laura Claire [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ottenfeld, Chelsea Faith [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Porterfield, Donivan R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rearick, Michael Sean [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rim, Jung Ho [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Schake, Ann Rene [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Schappert, Michael Francis [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Stanley, Floyd E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Thomas, Mariam R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wylie, Ernest Miller II [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Xu, Ning [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tandon, Lav [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-09-08

    Americium oxide samples will be measured for various analytes to support AmO<sub>2sub> production. The key analytes that are currently requested by the Am production customer at LANL include total Am content, Am isotopics, Pu assay, Pu isotopics, and trace element content including 237Np content. Multiple analytical methods will be utilized depending on the sensitivity, accuracy and precision needs of the Am matrix. Traceability to the National Institute of Standards and Technology (NIST) will be achieved, where applicable, by running NIST traceable quality control materials. This given that there are no suitable AmO<sub>2sub> reference materials currently available for requested analytes. The primary objective is to demonstrate the suitability of actinide analytical chemistry methods to support AmO<sub>2sub> production operations.

  12. Measurement of nu/sub e/ and anti nu/sub e/ elastic scattering as a test of the standard model

    International Nuclear Information System (INIS)

    Abe, K.; Taylor, F.E.; White, D.H.

    1982-01-01

    Various tests of standard SU(2) x U(1) model of weak interactions which can be performed by measurements of electron and muon neutrino-electron elastic scattering are reviewed. Electron neutrino-electron elastic scattering has both a neutral current part as well as a charged current part, and therefore offers a unique place to measure the interference of these two amplitudes. A measurement of the y-dependence of neutrino-electron elastic scattering can separately measure g/sub V/ and g/sub A/ as well as test for the presence of S, P, or T terms. Several measurable quantities involving cross sections and the interference term are derived from the standard model. Various design considerations for an experiment to determine the NC-CC interference term and the y-dependence of muon neutrino-electron elastic scattering are discussed

  13. V/V/sub max/ test for QSOs: comments on the paper by Hawkins and Stewart

    International Nuclear Information System (INIS)

    Wills, D.

    1983-01-01

    Hawkins and Stewart's interpretation of the results of the V/V/sub max/ test for QSO samples is shown to be invalid. Their suggestion that the high values of V/V/sub max/ at small redshifts result from the exclusion of nearby QSOs from the samples is examined quantitatively for the well-studied 3CR sample, and shown to have a negligible effect on the results. Their claim that the values of V/V/sub max/ at larger redshifts indicate a uniform space density of QSOs is not true after an error in their calculations is corrected. Although the V/V/sub max/ test is less sensitive to space density evolution at large redshifts, current results are in good agreement with the hypothesis that a single density evolution law describes the observations out to a redshift of at least 2.5

  14. Development of the Statistical Reasoning in Biology Concept Inventory (SRBCI)

    Science.gov (United States)

    Deane, Thomas; Nomme, Kathy; Jeffery, Erica; Pollock, Carol; Birol, Gülnur

    2016-01-01

    We followed established best practices in concept inventory design and developed a 12-item inventory to assess student ability in statistical reasoning in biology (Statistical Reasoning in Biology Concept Inventory [SRBCI]). It is important to assess student thinking in this conceptual area, because it is a fundamental requirement of being statistically literate and associated skills are needed in almost all walks of life. Despite this, previous work shows that non–expert-like thinking in statistical reasoning is common, even after instruction. As science educators, our goal should be to move students along a novice-to-expert spectrum, which could be achieved with growing experience in statistical reasoning. We used item response theory analyses (the one-parameter Rasch model and associated analyses) to assess responses gathered from biology students in two populations at a large research university in Canada in order to test SRBCI’s robustness and sensitivity in capturing useful data relating to the students’ conceptual ability in statistical reasoning. Our analyses indicated that SRBCI is a unidimensional construct, with items that vary widely in difficulty and provide useful information about such student ability. SRBCI should be useful as a diagnostic tool in a variety of biology settings and as a means of measuring the success of teaching interventions designed to improve statistical reasoning skills. PMID:26903497

  15. Using a Concept Inventory to Assess the Reasoning Component of Citizen-Level Science Literacy: Results from a 17,000-Student Study.

    Science.gov (United States)

    Nuhfer, Edward B; Cogan, Christopher B; Kloock, Carl; Wood, Gregory G; Goodman, Anya; Delgado, Natalie Zayas; Wheeler, Christopher W

    2016-03-01

    After articulating 12 concepts for the reasoning component of citizen-level science literacy and restating these as assessable student learning outcomes (SLOs), we developed a valid and reliable assessment instrument for addressing the outcomes with a brief 25-item science literacy concept inventory (SLCI). In this paper, we report the results that we obtained from assessing the citizen-level science literacy of 17,382 undergraduate students, 149 graduate students, and 181 professors. We address only findings at or above the 99.9% confidence level. We found that general education (GE) science courses do not significantly advance understanding of science as a way of knowing. However, the understanding of science's way of knowing does increase through academic ranks, indicating that the extended overall academic experience better accounts for increasing such thinking capacity than do science courses alone. Higher mean institutional SLCI scores correlate closely with increased institutional selectivity, as measured by the institutions' higher mean SAT and ACT scores. Socioeconomic factors of a) first-generation student, b) English as a native language, and c) interest in commitment to a science major are unequally distributed across ethnic groups. These factors proved powerful in accounting for the variations in SLCI scores across ethnicities and genders.

  16. Long-term corrosion tests of Ti{sub 3}SiC{sub 2} and Ti{sub 2}AlC in oxygen containing LBE at temperatures up to 700 °C

    Energy Technology Data Exchange (ETDEWEB)

    Heinzel, A., E-mail: Annette.heinzel@kit.edu; Weisenburger, A.; Müller, G.

    2016-12-15

    Two MAX-phase materials, Ti{sub 3}SiC and Ti{sub 2}AlC, were tested at 550 °C, 650 °C and 700 °C up to 10 000 h in LBE (lead-bismuth-eutectic) containing of 10{sup −6} and 10{sup −8} wt% oxygen. It was found that secondary phases have a strong influence on corrosion effects. Ti{sub 3}SiC showed a surface disintegration at 550°C/10{sup −6} wt% oxygen after longer exposure, while a 4–7 μm thick TiO{sub 2} layer with Pb-Bi inclusions was detected on Ti{sub 2}AlC. However, Ti{sub 3}SiC is protected by a double layered oxide with an outer part of TiO{sub 2} and a mixed inner layer of SiO{sub 2} and TiO{sub 2} at the higher temperatures. Ti{sub 2}AlC formed a TiO{sub 2} surface layer containing Al{sub 2}O{sub 3}. Some defects could be observed on the Ti{sub 3}SiC surface in LBE containing 10{sup −8} wt% oxygen at 550 °C and 650 °C. The secondary phases between the Ti{sub 3}SiC grains showed strong oxidation at 700 °C. Due to the high Al solubility in LBE, Ti{sub 2}AlC experienced strong dissolution attack after longer exposure times at 650 and 700 °C.

  17. Internal Structure and Partial Invariance across Gender in the Spanish Version of the Reasoning Test Battery.

    Science.gov (United States)

    Elosua, Paula; Mujika, Josu

    2015-10-13

    The Reasoning Test Battery (BPR) is an instrument built on theories of the hierarchical organization of cognitive abilities and therefore consists of different tasks related with abstract, numerical, verbal, practical, spatial and mechanical reasoning. It was originally created in Belgium and later adapted to Portuguese. There are three forms of the battery consisting of different items and scales which cover an age range from 9 to 22. This paper focuses on the adaptation of the BPR to Spanish, and analyzes different aspects of its internal structure: (a) exploratory item factor analysis was applied to assess the presence of a dominant factor for each partial scale; (b) the general underlined model was evaluated through confirmatory factor analysis, and (c) factorial invariance across gender was studied. The sample consisted of 2624 Spanish students. The results concluded the presence of a general factor beyond the scales, with equivalent values for men and women, and gender differences in the factorial structure which affect the numerical reasoning, abstract reasoning and mechanical reasoning scales.

  18. The script concordance test as a tool to evaluate clinical reasoning in neonatology.

    Science.gov (United States)

    Ben Hamida, Emira; Ayadi, Imen; Marrakchi, Zahra; Quinton, André

    2017-05-01

    Script concordance test aims to evaluate knowledge organization, which represents an essential component of the clinical competence. To build a script concordance test and demonstrate its relevance in the evaluation of Neonatology skills. A script concordance test including 20 vignettes and 20 items, was provided to 52 fourth year medical students and 11 family medicine interns. Script concordance test scores obtained by experts were higher then those obtained by students and family medicine interns. The scores (out of 100) were 82.52 ± 7.35 CI95% [77.26-87.78] for the experts, 58.52 ± 9.72 CI95% [55.82-61.23] for the students, and 63.17±11.36 IC95%  [55.53-70.81] (p<0.0001) for the interns. Our data suggest that script concordance tests could be used to assess the acquisition of clinical reasoning among fourth year medical students in neonatolgy.

  19. Why Students Answer TIMSS Science Test Items the Way They Do

    Science.gov (United States)

    Harlow, Ann; Jones, Alister

    2004-04-01

    The purpose of this study was to explore how Year 8 students answered Third International Mathematics and Science Study (TIMSS) questions and whether the test questions represented the scientific understanding of these students. One hundred and seventy-seven students were tested using written test questions taken from the science test used in the Third International Mathematics and Science Study. The degree to which a sample of 38 children represented their understanding of the topics in a written test compared to the level of understanding that could be elicited by an interview is presented in this paper. In exploring student responses in the interview situation this study hoped to gain some insight into the science knowledge that students held and whether or not the test items had been able to elicit this knowledge successfully. We question the usefulness and quality of data from large-scale summative assessments on their own to represent student scientific understanding and conclude that large scale written test items, such as TIMSS, on their own are not a valid way of exploring students'' understanding of scientific concepts. Considerable caution is therefore needed in exploiting the outcomes of international achievement testing when considering educational policy changes or using TIMSS data on their own to represent student understanding.

  20. Testing the E(sub peak)-E(sub iso) Relation for GRBs Detected by Swift and Suzaku-WAM

    Science.gov (United States)

    Krimm, H. A.; Yamaoka, K.; Sugita, S.; Ohno, M.; Sakamoto, T.; Barthelmy, S. D.; Gehrels, N.; Hara, R.; Onda, K.; Sato, G.; hide

    2009-01-01

    One of the most prominent, yet controversial associations derived from the ensemble of prompt-phase observations of gamma-ray bursts (GRBs) is the apparent correlation in the source frame between the peak energy (E(sub peak)) of the nuF(nu) spectrum and the isotropic radiated energy, E(sub iso). Since most gamma-ray bursts (GRBs) have E(sub peak) above the energy range (15-150 keV) of the Burst Alert Telescope (BAT) on Swift, determining accurate E(sub peak) values for large numbers of Swift bursts has been difficult. However, by combining data from Swift/BAT and the Suzaku Wide-band All-Sky Monitor (WAM), which covers the energy range from 50-5000 keV, for bursts which are simultaneously detected ; one can accurately fit E(sub peak) and E(sub iso) and test the relationship between them for the Swift sample. Between the launch of Suzaku in July 2005 and the end of March 2009, there were 45 gamma-ray bursts (GRBs) which triggered both Swift/BAT and WAM and an additional 47 bursts which triggered Swift and were detected by WAM, but did not trigger. A BAT-WAM team has cross-calibrated the two instruments using GRBs, and we are now able to perform joint fits on these bursts to determine spectral parameters. For those bursts with spectroscopic redshifts.. we can also calculate the isotropic energy. Here we present the results of joint Swift/BAT-Suzaku/WAM spectral fits for 86 of the bursts detected by the two instruments. We show that the distribution of spectral fit parameters is consistent with distributions from earlier missions and confirm that Swift, bursts are consistent with earlier reported relationships between Epeak and isotropic energy. We show through time-resolved spectroscopy that individual burst pulses are also consistent with this relationship.

  1. RELATION BETWEEN EMOTIONAL INTELLIGENCE AND REASONING ABILITY OF HIGHER SECONDARY STUDENTS

    OpenAIRE

    C. Daisy Nambikkai; Dr. A.Veliappan

    2017-01-01

    The present study aims to find out the relationship between emotional intelligence and reasoning ability of the higher secondary students. Among the population, 724 samples of higher secondary students were selected randomly from Puducherry region. Findings of the study were i) significant difference is found between male and female higher secondary students in their reasoning ability in science on analogical reasoning, classification as reasoning, eclectic reasoning, deductive reasoning and ...

  2. CO{sub 2} Capture by Sub-ambient Membrane Operation

    Energy Technology Data Exchange (ETDEWEB)

    Kulkarni, S.; Hasse, D.; Sanders, E.; Chaubey, T.

    2012-11-30

    The main objective of the project was to develop a CO{sub 2} capture process based on sub-ambient temperature operation of a hollow fiber membrane. The program aims to reach the eventual DOE program goal of > 90% CO{sub 2} capture from existing PC fired power plants with < 35% increase in the cost of electricity. The project involves closed-loop testing of commercial fiber bundles under simulated process conditions to test the mechanical integrity and operability of membrane module structural component under sub ambient temperature. A commercial MEDAL 12” bundle exhibited excellent mechanical integrity for 2 months. However, selectivity was ~25% lower than expected at sub-ambient conditions. This could be attributed to a small feed to permeate leak or bundle non-ideality. To investigate further, and due to compressor flow limitations, the 12” bundle was replaced with a 6” bundle to conduct tests with lower permeate/feed ratios, as originally planned. The commercial 6” bundle was used for both parametric testing as well as long-term stability testing at sub-ambient conditions. Parametric studies were carried out both near the start and end of the long-term test. The parametric studies characterized membrane performance over a broad range of feed conditions: temperature (-25°C to -45°C), pressure (160 psig to 200 psig), and CO{sub 2} feed concentration (18% to 12%). Performance of the membrane bundle was markedly better at lower temperature (-45ºC), higher pressure (200 psig) and higher CO{sub 2} feed concentration (18%). The long-term test was conducted at these experimentally determined “optimum” feed conditions. Membrane performance was stable over 8 months at sub-ambient temperature operation. The experimentally measured high performance of the membrane bundle at sub-ambient operating conditions provides justification for interest in sub-ambient membrane processing of flue gas. In a parallel activity, the impact of contaminants (100 ppm SOx and NOx

  3. Improvement of photoluminescence properties and thermal stability of Y{sub 2.9}Ce{sub 0.1}Al{sub 5−x}Si{sub x}O{sub 12} phosphors with Si{sub 3}N{sub 4} addition

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fangfang [College of Electronic Information and Engineering, Hangzhou Dianzi University, Hangzhou 310018 (China); Song, Kaixin, E-mail: kxsong@hdu.edu.cn [College of Electronic Information and Engineering, Hangzhou Dianzi University, Hangzhou 310018 (China); Jiang, Jun [Ningbo Institute of Materials Technologies and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Wu, Song; Zheng, Peng [College of Electronic Information and Engineering, Hangzhou Dianzi University, Hangzhou 310018 (China); Huang, Qingming [Instrument Analysis and Testing Center, Fuzhou University, Fuzhou 350002 (China); Xu, Junming; Qin, Huibin [College of Electronic Information and Engineering, Hangzhou Dianzi University, Hangzhou 310018 (China)

    2014-12-05

    Highlights: • Y{sub 2.9}Ce{sub 0.1}Al{sub 5−x}Si{sub x}O{sub 12} phosphors were prepared by solid-state reaction in reduced air ambience. • Si{sup 4+} could be incorporated into the host lattice of Y{sub 3}Al{sub 5}O{sub 12} through partial occupation of the Al{sup 3+} sites. • Si{sub 3}N{sub 4} addition can improve photoluminescence efficiency and thermal stability of Y{sub 3}Al{sub 5}O{sub 12}:Ce. - Abstract: A series of Si{sub 3}N{sub 4} doping Y{sub 2.9}Ce{sub 0.1}Al{sub 5−x}Si{sub x}O{sub 12−3x/2}N{sub 4x/3} phosphors were prepared by solid-state reaction in 95%N{sub 2}–5%H{sub 2} reduced air ambience. The XRD characteristics plus Rietveld refinement results shows that the as-sintered powders are unique crystal phase with the same crystal structure of Y{sub 3}Al{sub 5}O{sub 12} (PDF No. 79-1891). The N element was not detected by the analysis of X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectrum (EDS). The photoluminescence spectra (PL and PLE) tests show that the exciting and emitting intensity of PLE and PL gradually increase due to the increase of Si{sub 3}N{sub 4} concentration. Meanwhile, the phosphorescence decay times are prolonged from 45 ns (x = 0) to 78 ns (x = 0.3), under the monitor of 530 nm wavelength. The thermoluminescence tests (TL) confirm the thermal stability of as-phosphors with Si{sub 3}N{sub 4} addition is much better than that of the pristine Y{sub 2.9}Ce{sub 0.1}Al{sub 5}O{sub 12} phosphors.

  4. In{sub 2}O{sub 3}/Bi{sub 2}Sn{sub 2}O{sub 7} heterostructured nanoparticles with enhanced photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Xing, Yonglei [Electronic Materials Research Laboratory, International Center for Dielectric Research, Key Laboratory of the Ministry of Education, School of Electronic and Information Engineering, State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, Shaanxi (China); Que, Wenxiu, E-mail: wxque@mail.xjtu.edu.cn [Electronic Materials Research Laboratory, International Center for Dielectric Research, Key Laboratory of the Ministry of Education, School of Electronic and Information Engineering, State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, Shaanxi (China); Yin, Xingtian; He, Zuoli; Liu, Xiaobin; Yang, Yawei; Shao, Jinyou [Electronic Materials Research Laboratory, International Center for Dielectric Research, Key Laboratory of the Ministry of Education, School of Electronic and Information Engineering, State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, Shaanxi (China); Kong, Ling Bing, E-mail: ELBKong@ntu.edu.sg [School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore)

    2016-11-30

    Highlights: • Visible-light photocatalytic activities of the nanostructured In{sub 2}O{sub 3}/Bi{sub 2}Sn{sub 2}O{sub 7} heterostructures were studied. • Effect of In{sub 2}O{sub 3} content on the photocatalytic activity of the In{sub 2}O{sub 3}/Bi{sub 2}Sn{sub 2}O{sub 7} heterostructure was evaluated. • 0.1In{sub 2}O{sub 3}/Bi{sub 2}Sn{sub 2}O{sub 7} heterostructure photocatalyst shows a superior photocatalytic activity. • Based on Mott-Schottky analysis and active species detection, a mechanism for the separation of photogenerated carriers is proposed. • The effective separation process of the photogenerated electron-hole pairs was testified by photocurrent test. - Abstract: In{sub 2}O{sub 3}/Bi{sub 2}Sn{sub 2}O{sub 7} composite photocatalysts with various contents of cubic In{sub 2}O{sub 3} nanoparticles were fabricated by using impregnation method. A thriving modification of Bi{sub 2}Sn{sub 2}O{sub 7} by an introduction of In{sub 2}O{sub 3} was confirmed by using X-ray diffraction, UV–vis diffuse reflectance spectrometry, transmission electron microscopy, high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy. The samples composed of hybrids of In{sub 2}O{sub 3} and Bi{sub 2}Sn{sub 2}O{sub 7} exhibited a much higher photocatalytic activity for the degradation of Rhodamine B under visible light, as compared with pure In{sub 2}O{sub 3} and Bi{sub 2}Sn{sub 2}O{sub 7} nanoparticles. Optimized composition of the composite photocatalysts was 0.1In{sub 2}O{sub 3}/Bi{sub 2}Sn{sub 2}O{sub 7}, which shows a rate constant higher than those of pure In{sub 2}O{sub 3} and Bi{sub 2}Sn{sub 2}O{sub 7} by 4.06 and 3.21 times, respectively. Based on Mott-Schottky analysis and active species detection, the photoexcited electrons in the conduction band of In{sub 2}O{sub 3} and the holes in the valence band of Bi{sub 2}Sn{sub 2}O{sub 7} participated in reduction and oxidation reactions, respectively. Hence, ·OH, ·O{sub 2}{sup −} and h

  5. Connecting mathematics learning through spatial reasoning

    Science.gov (United States)

    Mulligan, Joanne; Woolcott, Geoffrey; Mitchelmore, Michael; Davis, Brent

    2018-03-01

    Spatial reasoning, an emerging transdisciplinary area of interest to mathematics education research, is proving integral to all human learning. It is particularly critical to science, technology, engineering and mathematics (STEM) fields. This project will create an innovative knowledge framework based on spatial reasoning that identifies new pathways for mathematics learning, pedagogy and curriculum. Novel analytical tools will map the unknown complex systems linking spatial and mathematical concepts. It will involve the design, implementation and evaluation of a Spatial Reasoning Mathematics Program (SRMP) in Grades 3 to 5. Benefits will be seen through development of critical spatial skills for students, increased teacher capability and informed policy and curriculum across STEM education.

  6. Electrochemical behavior of [(Mn(Bpy))(VO{sub 3}){sub 2}]≈(H{sub 2}O){sub 1.24} and [(Mn(Bpy){sub 0.5})(VO{sub 3}){sub 2}]≈(H{sub 2}O){sub 0.62} inorganic–organic Brannerites in lithium and sodium cells

    Energy Technology Data Exchange (ETDEWEB)

    Fernández de Luis, Roberto, E-mail: roberto.fernandez@ehu.es [Departamento de Mineralogía y Petrología, Facultad de Ciencia y Tecnología, Universidad del País Vasco, UPV/EHU, Apdo. 644, E-48080 Bilbao (Spain); Ponrouch, Alexandre, E-mail: aponrouch@icmab.es [Institut de Ciència de Materials de Barcelona (CSIC) Campus UAB, E-08193, Bellaterra, Catalonia (Spain); Rosa Palacín, M., E-mail: rosa.palacin@icmab.es [Institut de Ciència de Materials de Barcelona (CSIC) Campus UAB, E-08193, Bellaterra, Catalonia (Spain); Karmele Urtiaga, M., E-mail: karmele.urtiaga@ehu.es [Departamento de Mineralogía y Petrología, Facultad de Ciencia y Tecnología, Universidad del País Vasco, UPV/EHU, Apdo. 644, E-48080 Bilbao (Spain); Arriortua, María I., E-mail: maribel.arriortua@ehu.es [Departamento de Mineralogía y Petrología, Facultad de Ciencia y Tecnología, Universidad del País Vasco, UPV/EHU, Apdo. 644, E-48080 Bilbao (Spain)

    2014-04-01

    The performance of MnV{sub 2}O{sub 6} (MnV) and its [(Mn(Bpy))(VO{sub 3}){sub 2}]≈(H{sub 2}O){sub 1.16} (MnBpy) and [(Mn(Bpy){sub 0.5})(VO{sub 3}){sub 2}]≈(H{sub 2}O){sub 0.62}(MnBpy0.5) hybrid derivative compounds was investigated against sodium and lithium counter electrodes. For MnV{sub 2}O{sub 6} stable capacities of 850 mAh/g were achieved in lithium cells, the best value reported so far. The whole capacity is ascribed to a conversion reaction in which the amorphization of the compounds takes place. No significant differences in the capacities for the inorganic compound and the hybrid ones were observed. Interestingly, the potential hysteresis decreases in the hybrid compounds. The difference between Li and Na cell capacity most probably comes from the difference of standard potential of the two redox couples Li{sup +}/Li and Na{sup +}/Na of about ca. 0.3 V leading to an incomplete conversion reaction and thus lowers capacity in the case of Na cells. The Raman and IR ex-situ experiments after cycling indicate that the bipyridine organic ligands are completely decomposed during the electrochemical testing. The IR studies in MnV inorganic and MnBpy and MnBpy0.5 hybrid electrodes after the electrochemical cycling, suggest that the SEI formation and bipyridine degradation give rise to different aliphatic compounds. - Graphical abstract: The electrochemical performance of [(Mn(Bpy))(VO{sub 3}){sub 2}]≈(H{sub 2}O){sub 1.16} and [(Mn(Bpy){sub 0.5})(VO{sub 3}){sub 2}]≈(H{sub 2}O){sub 0.62} against sodium and lithium counter electrodes give rise to the structural collapse of the initial compounds. The IR and Raman studies show that the Bpy organic ligand is completely decomposed during the during the electrochemical testing. However, after the amorphization stable capacities as high as 850 mAh/g for lithium cells were achieved. - Highlights: • We test the lithium and sodium insertion in hybrid brannerites. • Capacities as large as 850 mAh/g were obtained

  7. UF{sub 6} cylinder fire test

    Energy Technology Data Exchange (ETDEWEB)

    Park, S.H. [Oak Ridge K-25 Site, Oak Ridge, TN (United States)

    1991-12-31

    With the increasing number of nuclear reactors for power generation, there is a comparable increase in the amount of UF{sub 6} being transported. Likewise, the probability of having an accident involving UF{sub 6}-filled cylinders also increases. Accident scenarios which have been difficult to assess are those involving a filled UF{sub 6} cylinder subjected to fire. A study is underway at the Oak Ridge K-25 Site, as part of the US DOE Enrichment Program, to provide empirical data and a computer model that can be used to evaluate various cylinder-in-fire scenarios. It is expected that the results will provide information leading to better handling of possible fire accidents as well as show whether changes should be made to provide different physical protection during shipment. The computer model being developed will be capable of predicting the rupture of various cylinder sizes and designs as well as the amount of UF{sub 6}, its distribution in the cylinder, and the conditions of the fire.

  8. On Line Enrichment Monitor (OLEM) UF<sub>6sub> Tests for 1.5" Sch40 SS Pipe, Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    March-Leuba, José A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Garner, Jim [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Younkin, Jim [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Simmons, Darrell W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-01-01

    sub> gas within the unit header pipe as a function of time. The OLEM components have been tested on ORNL UF<sub>6sub> flow loop. Data were collected at five different enrichment levels (0.71%, 2.97%, 4.62%, 6.0%, and 93.7%) at several pressure conditions. The test data were collected in the standard OLEM N.4242 file format for each of the conditions with a 10-minute sampling period and then averaged over the span of constant pressures. Analysis of the collected data has provided enrichment constants that can be used for 1.5” stainless steel schedule 40 pipe measurement sites. The enrichment constant is consistent among all the wide range of enrichment levels and pressures used.

  9. Using a Concept Inventory to Assess the Reasoning Component of Citizen-Level Science Literacy: Results from a 17,000-Student Study

    Directory of Open Access Journals (Sweden)

    Edward B. Nuhfer

    2015-12-01

    Full Text Available After articulating 12 concepts for the reasoning component of citizen-level science literacy and restating these as assessable student learning outcomes (SLOs, we developed a valid and reliable assessment instrument for addressing the outcomes with a brief 25-item science literacy concept inventory (SLCI. In this paper, we report the results that we obtained from assessing the citizen-level science literacy of 17,382 undergraduate students, 149 graduate students, and 181 professors. We address only findings at or above the 99.9% confidence level. We found that general education (GE science courses do not significantly advance understanding of science as a way of knowing. However, the understanding of science’s way of knowing does increase through academic ranks, indicating that the extended overall academic experience better accounts for increasing such thinking capacity than do science courses alone. Higher mean institutional SLCI scores correlate closely with increased institutional selectivity, as measured by the institutions’ higher mean SAT and ACT scores. Socioeconomic factors of a first-generation student, b English as a native language, and c interest in commitment to a science major are unequally distributed across ethnic groups. These factors proved powerful in accounting for the variations in SLCI scores across ethnicities and genders.

  10. Using a Concept Inventory to Assess the Reasoning Component of Citizen-Level Science Literacy: Results from a 17,000-Student Study†

    Science.gov (United States)

    Nuhfer, Edward B.; Cogan, Christopher B.; Kloock, Carl; Wood, Gregory G.; Goodman, Anya; Delgado, Natalie Zayas; Wheeler, Christopher W.

    2016-01-01

    After articulating 12 concepts for the reasoning component of citizen-level science literacy and restating these as assessable student learning outcomes (SLOs), we developed a valid and reliable assessment instrument for addressing the outcomes with a brief 25-item science literacy concept inventory (SLCI). In this paper, we report the results that we obtained from assessing the citizen-level science literacy of 17,382 undergraduate students, 149 graduate students, and 181 professors. We address only findings at or above the 99.9% confidence level. We found that general education (GE) science courses do not significantly advance understanding of science as a way of knowing. However, the understanding of science’s way of knowing does increase through academic ranks, indicating that the extended overall academic experience better accounts for increasing such thinking capacity than do science courses alone. Higher mean institutional SLCI scores correlate closely with increased institutional selectivity, as measured by the institutions’ higher mean SAT and ACT scores. Socioeconomic factors of a) first-generation student, b) English as a native language, and c) interest in commitment to a science major are unequally distributed across ethnic groups. These factors proved powerful in accounting for the variations in SLCI scores across ethnicities and genders. PMID:27047612

  11. Model-independent test of the FLRW metric, the flatness of the Universe, and non-local estimation of H {sub 0} r {sub d}

    Energy Technology Data Exchange (ETDEWEB)

    L' Huillier, Benjamin; Shafieloo, Arman, E-mail: benjamin@kasi.re.kr, E-mail: shafieloo@kasi.re.kr [Korea Astronomy and Space Science Institute, Yuseong-gu, 776 Daedeok daero, Daejeon (Korea, Republic of)

    2017-01-01

    Using measurements of H ( z ) and d {sub A}( z ) from the Baryon Oscillation Spectroscopic Survey (BOSS) DR12 and luminosity distances from the Joint Lightcurve Analysis (JLA) compilation of supernovae (SN), we measure H {sub 0} {sub r} {sub d} without any model assumption. Our measurement of H {sub 0} r {sub d} = (10033.20{sup +333.10}{sub −371.81} (SN) ± 128.19 (BAO)) km s{sup −1} is consistent with Planck constrains for the flat ΛCDM model. We also report that higher expansion history rates h ( z ) (among the possibilities) as well as lower-bound values of H {sub 0} r {sub d} result in better internal consistency among the independent data ( H ( z ) r {sub d} and d {sub A}( z )/ r {sub d} from BAO at z =0.32 and z =0.57 and d {sub L} from JLA) we used in this work. This can be interpreted as an interesting and independent support of Planck cosmology without using any cosmic microwave background data. We then combine these observables to test the Friedmann-Lemaȋtre-Robertson-Walker (FLRW) metric and the flatness of the Universe in a model-independent way at two redshifts, namely 0.32 and 0.57, by introducing a new diagnostic for flat-FLRW, Θ( z ), which only depends on observables of BAO and SN data. Our results are consistent with a flat-FLRW Universe within 2σ.

  12. 3081//sub E/ processor

    International Nuclear Information System (INIS)

    Kunz, P.F.; Gravina, M.; Oxoby, G.; Trang, Q.; Fucci, A.; Jacobs, D.; Martin, B.; Storr, K.

    1983-03-01

    Since the introduction of the 168//sub E/, emulating processors have been successful over an amazingly wide range of applications. This paper will describe a second generation processor, the 3081//sub E/. This new processor, which is being developed as a collaboration between SLAC and CERN, goes beyond just fixing the obvious faults of the 168//sub E/. Not only will the 3081//sub E/ have much more memory space, incorporate many more IBM instructions, and have much more memory space, incorporate many more IBM instructions, and have full double precision floating point arithmetic, but it will also have faster execution times and be much simpler to build, debug, and maintain. The simple interface and reasonable cost of the 168//sub E/ will be maintained for the 3081//sub E/

  13. Science Library of Test Items. Volume Eleven. Mastery Testing Programme. [Mastery Tests Series 3.] Tests M27-M38.

    Science.gov (United States)

    New South Wales Dept. of Education, Sydney (Australia).

    As part of a series of tests to measure mastery of specific skills in the natural sciences, copies of tests 27 through 38 include: (27) reading a grid plan; (28) identifying common invertebrates; (29) characteristics of invertebrates; (30) identifying elements; (31) using scientific notation part I; (32) classifying minerals; (33) predicting the…

  14. Does the Cognitive Reflection Test actually capture heuristic versus analytic reasoning styles in older adults?

    Science.gov (United States)

    Hertzog, Christopher; Smith, R Marit; Ariel, Robert

    2018-01-01

    Background/Study Context: This study evaluated adult age differences in the original three-item Cognitive Reflection Test (CRT; Frederick, 2005, The Journal of Economic Perspectives, 19, 25-42) and an expanded seven-item version of that test (Toplak et al., 2013, Thinking and Reasoning, 20, 147-168). The CRT is a numerical problem-solving test thought to capture a disposition towards either rapid, intuition-based problem solving (Type I reasoning) or a more thoughtful, analytical problem-solving approach (Type II reasoning). Test items are designed to induce heuristically guided errors that can be avoided if using an appropriate numerical representation of the test problems. We evaluated differences between young adults and old adults in CRT performance and correlates of CRT performance. Older adults (ages 60 to 80) were paid volunteers who participated in experiments assessing age differences in self-regulated learning. Young adults (ages 17 to 35) were students participating for pay as part of a project assessing measures of critical thinking skills or as a young comparison group in the self-regulated learning study. There were age differences in the number of CRT correct responses in two independent samples. Results with the original three-item CRT found older adults to have a greater relative proportion of errors based on providing the intuitive lure. However, younger adults actually had a greater proportion of intuitive errors on the long version of the CRT, relative to older adults. Item analysis indicated a much lower internal consistency of CRT items for older adults. These outcomes do not offer full support for the argument that older adults are higher in the use of a "Type I" cognitive style. The evidence was also consistent with an alternative hypothesis that age differences were due to lower levels of numeracy in the older samples. Alternative process-oriented evaluations of how older adults solve CRT items will probably be needed to determine

  15. David Lukens Reasoner (1941-1992)

    Science.gov (United States)

    Chappell, Rick

    David Lukens Reasoner, former head of NASA's Ionospheric Physics branch, died on April 21, 1992. Reasoner was born July 1, 1941. He worked tirelessly to expand NASA's Space Physics Division, bringing his deep experience and personal expertise to bear on the challenges of growth.During the magical period of the late 1950s and early 1960s when America turned its eyes toward space and the Moon, David Lukens Reasoner journeyed north from the nearby Texas town of Dickinson to Rice University with an idea of getting involved in exploring the frontiers of space. He pursued a course of study in electrical engineering and received a bachelor's degree in 1963 and a master's degree in 1964. In the early 1960s, the Space Science Department at Rice was formed, and President John Kennedy visited to say that America chose to go to space not because it is easy but because it is hard and because it would require the very best talents of our nation to succeed. Dave Reasoner was one of those talented people. His excellence in electrical engineering and physics, combined with his natural abilities in the laboratory, suited him ideally for building the machines of space. As a student, he built sounding rocket payloads and multiple instruments for satellites and experiment packages that were placed on the Moon by the Apollo astronauts. He completed his doctoral degree in space science in 1968. It was in these early thrilling days of space exploration that I first met Dave, beginning a friendship and collegial relationship that was to last 27 years.

  16. Atmospheric Fluidized Bed Combustion testing of North Dakota lignite

    Energy Technology Data Exchange (ETDEWEB)

    Goblirsch, G; Vander Molen, R H; Wilson, K; Hajicek, D

    1980-05-01

    The sulfur retention by the inherent alkali, and added limestone sorbent, perform about the same and are reasonably predictable within a range of about +-10% retention by application of alkali to sulfur ratio. Temperature has a substantial effect on the retention of sulfur by the inherent alkali or limestone. The temperature effect is not yet fully understood but it appears to be different for different coals and operational conditions. The emission of SO/sub 2/ from the fluid bed burning the Beulah lignite sample used for these tests can be controlled to meet or better the current emission standards. The injection of limestone to an alkali-to-sulfur molar ratio of 1.5 to 1, should lower the SO/sub 2/ emissions below the current requirement of 0.6 lb SO/sub 2//10/sup 6/ Btu to 0.4 lb SO/sub 2//10/sup 6/ Btu, a safe 33% below the standard. Agglomeration of bed material, and consequent loss of fluidization quality can be a problem when burning high sodium lignite in a silica bed. There appears, however, to be several ways of controlling the problem including the injection of calcium compounds, and careful control of operating conditions. The heat transfer coefficients measured in the CPC and GFETC tests are comparable to data obtained by other researchers, and agree reasonably well with empirical conditions. The NO/sub x/ emissions measured in all of the tests on Beulah lignite are below the current New Source Performance Standard of 0.5 lb NO/sub 2//10/sup 6/ Btu input. Combustion efficiencies for the Beulah lignite are generally quite high when ash recycle is being used. Efficiencies in the range of 98% to 99%+ have been measured in all tests using this fuel.

  17. Mechanism of thermal decomposition of K{sub 2}FeO{sub 4} and BaFeO{sub 4}: A review

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Virender K., E-mail: vsharma@sph.tamhsc.edu [Texas A& M University, Department of Environmental and Occupational Health, School of Public Health (United States); Machala, Libor [Palacky University, Regional Centre of Advanced Technologies and Materials, Departments of Experimental Physics and Physical Chemistry, Faculty of Science (Czech Republic)

    2016-12-15

    This paper presents thermal decomposition of potassium ferrate(VI) (K{sub 2}FeO{sub 4}) and barium ferrate(VI) (BaFeO{sub 4}) in air and nitrogen atmosphere. Mössbauer spectroscopy and nuclear forward scattering (NFS) synchrotron radiation approaches are reviewed to advance understanding of electron-transfer processes involved in reduction of ferrate(VI) to Fe(III) phases. Direct evidences of Fe {sup V} and Fe {sup IV} as intermediate iron species using the applied techniques are given. Thermal decomposition of K{sub 2}FeO{sub 4} involved Fe {sup V}, Fe {sup IV}, and K{sub 3}FeO{sub 3} as intermediate species while BaFeO{sub 3} (i.e. Fe {sup IV}) was the only intermediate species during the decomposition of BaFeO{sub 4}. Nature of ferrite species, formed as final Fe(III) species, of thermal decomposition of K{sub 2}FeO{sub 4} and BaFeO{sub 4} under different conditions are evaluated. Steps of the mechanisms of thermal decomposition of ferrate(VI), which reasonably explained experimental observations of applied approaches in conjunction with thermal and surface techniques, are summarized.

  18. Note on a simple test method for estimaing J/sub Ic/

    International Nuclear Information System (INIS)

    Whipple, T.A.; McHenry, H.I.

    1980-01-01

    Fracture toughness testing is generally a time-consuming and expensive procedure; therefore, there has been a significant amount of effort directed toward developing an inexpensive and rapid method of estimating the fracture toughness of materials. In this paper, a simple method for estimating J/sub Ic/ through the use of small, notched, bend bars is evaluated. The test only involves the measurement of the energy necessary to fracture the sample. Initial tests on Fe-18Cr-3Ni-13Mn and 304L stainless steel at 76 and 4 0 K have yielded results consistent with other fracture toughness tests, for materials in the low- to medium-toughness range

  19. Testing the efficiency of rover science protocols for robotic sample selection: A GeoHeuristic Operational Strategies Test

    Science.gov (United States)

    Yingst, R. A.; Bartley, J. K.; Chidsey, T. C.; Cohen, B. A.; Gilleaudeau, G. J.; Hynek, B. M.; Kah, L. C.; Minitti, M. E.; Williams, R. M. E.; Black, S.; Gemperline, J.; Schaufler, R.; Thomas, R. J.

    2018-05-01

    The GHOST field tests are designed to isolate and test science-driven rover operations protocols, to determine best practices. During a recent field test at a potential Mars 2020 landing site analog, we tested two Mars Science Laboratory data-acquisition and decision-making methods to assess resulting science return and sample quality: a linear method, where sites of interest are studied in the order encountered, and a "walkabout-first" method, where sites of interest are examined remotely before down-selecting to a subset of sites that are interrogated with more resource-intensive instruments. The walkabout method cost less time and fewer resources, while increasing confidence in interpretations. Contextual data critical to evaluating site geology was acquired earlier than for the linear method, and given a higher priority, which resulted in development of more mature hypotheses earlier in the analysis process. Combined, this saved time and energy in the collection of data with more limited spatial coverage. Based on these results, we suggest that the walkabout method be used where doing so would provide early context and time for the science team to develop hypotheses-critical tests; and that in gathering context, coverage may be more important than higher resolution.

  20. Modeling mental spatial reasoning about cardinal directions.

    Science.gov (United States)

    Schultheis, Holger; Bertel, Sven; Barkowsky, Thomas

    2014-01-01

    This article presents research into human mental spatial reasoning with orientation knowledge. In particular, we look at reasoning problems about cardinal directions that possess multiple valid solutions (i.e., are spatially underdetermined), at human preferences for some of these solutions, and at representational and procedural factors that lead to such preferences. The article presents, first, a discussion of existing, related conceptual and computational approaches; second, results of empirical research into the solution preferences that human reasoners actually have; and, third, a novel computational model that relies on a parsimonious and flexible spatio-analogical knowledge representation structure to robustly reproduce the behavior observed with human reasoners. Copyright © 2014 Cognitive Science Society, Inc.

  1. Study of microstructure and correlative magnetic property in bulk Fe{sub 61}Nd{sub 10}B{sub 25}Nb{sub 4} permanent magnet

    Energy Technology Data Exchange (ETDEWEB)

    Man, H.; Xu, H. [Laboratory for Microstructures, Shanghai University, Shanghai 200444 (China); Liu, H.W. [The Australian Centre for Microscopy and Microanalysis, The University of Sydney, NSW 2006 (Australia); Tan, X.H., E-mail: tanxiaohua123@163.com [Laboratory for Microstructures, Shanghai University, Shanghai 200444 (China); Peng, J.C.; Bai, Q. [Laboratory for Microstructures, Shanghai University, Shanghai 200444 (China)

    2012-11-01

    Highlights: Black-Right-Pointing-Pointer A fully dense bulk Fe{sub 61}Nd{sub 10}B{sub 25}Nb{sub 4} permanent magnet was obtained by the simple process of copper mold casting and subsequent annealed at 943 K. Black-Right-Pointing-Pointer The relationship between microstructures and correlative magnetic property of Fe{sub 61}Nd{sub 10}B{sub 25}Nb{sub 4} alloy was investigated. Black-Right-Pointing-Pointer The high value of intrinsic coercivity of 1191 kA/m was obtained due to the existence of hard magnetic Nd{sub 2}Fe{sub 14}B phase. - Abstract: The correlation between microstructure and magnetic property of a bulk Fe{sub 61}Nd{sub 10}B{sub 25}Nb{sub 4} alloy are investigated. The microstructure of the as-cast Fe{sub 61}Nd{sub 10}B{sub 25}Nb{sub 4} alloy shows a small amount of NbFeB phase with a grain size of 500 nm embedded in an amorphous matrix. The as-cast sample shows soft magnetic behavior at room temperature, after a heat treatment the hard magnetic properties are observed. A fully dense bulk Fe{sub 61}Nd{sub 10}B{sub 25}Nb{sub 4} permanent magnet is obtained with an intrinsic coercivity ({sub i}H{sub c}) of 1191 kA/m and a maximum energy product ((BH){sub max}) of 31.7 kJ/m{sup 3} after annealing at 943 K for 20 min. The corresponding microstructure consists of Nd{sub 2}Fe{sub 14}B, NdFe{sub 4}B{sub 4} and NbFeB phases. The existence of the hard magnetic Nd{sub 2}Fe{sub 14}B phase is the reason resulting in a high value of {sub i}H{sub c}. On the other hand, the influences of NdFe{sub 4}B{sub 4} and NbFeB phases in the annealed specimen on the magnetic properties are also discussed.

  2. Academic Achievement in Physics-Chemistry: The Predictive Effect of Attitudes and Reasoning Abilities

    Directory of Open Access Journals (Sweden)

    Paulo N. Vilia

    2017-06-01

    Full Text Available Science education plays a critical role as political priority due to its fundamental importance in engaging students to pursue technological careers considered essential in modern societies, in order to face scientific development challenges. High-level achievement on science education and positive attitudes toward science constitutes a crucial challenge for formal education. Several studies indicate close relationships between students’ attitudes, cognitive abilities, and academic achievement. The main purpose of this study is to analyze the impact of student’s attitudes toward the school discipline of Physics and Chemistry and their reasoning abilities on academic achievement on that school subject, among Portuguese 9th grade students using the data collected during the Project Academic Performance and Development: a longitudinal study on the effects of school transitions in Portuguese students (PTDC/CPE-CED/104884/2008. The participants were 470 students (267 girls – 56.8% and 203 boys – 43.2%, aged 14–16 years old (μ = 14.3 ± 0.58. The attitude data were collected using the Attitude toward Physics-Chemistry Questionnaire (ATPCQ and, the Reasoning Test Battery (RTB was used to assess the students reasoning abilities. Achievement was measured using the students’ quarterly (9-week grades in the physics and chemistry subject. The relationships between the attitude dimensions toward Physics-chemistry and the reasoning dimensions and achievement in each of the three school terms were assessed by multiple regression stepwise analyses and standardized regression coefficients (β, calculated with IBM SPSS Statistics 21 software. Both variables studied proved to be significant predictor variables of school achievement. The models obtained from the use of both variables were always stronger accounting for higher proportions of student’s grade variations. The results show that ATPCQ and RTB had a significantly positive relationship with

  3. Science Library of Test Items. Volume Ten. Mastery Testing Programme. [Mastery Tests Series 2.] Tests M14-M26.

    Science.gov (United States)

    New South Wales Dept. of Education, Sydney (Australia).

    As part of a series of tests to measure mastery of specific skills in the natural sciences, copies of tests 14 through 26 include: (14) calculating an average; (15) identifying parts of the scientific method; (16) reading a geological map; (17) identifying elements, mixtures and compounds; (18) using Ohm's law in calculation; (19) interpreting…

  4. Study on the thyroid function of thoroughbred horses by means of 'in vitro' /sup 125/I-T/sub 3/ modified and /sup 125/I-T/sub 4/ tests

    Energy Technology Data Exchange (ETDEWEB)

    de Martin, B W [Sao Paulo Univ. (Brazil). Faculdade de Medicina Veterinaria e Zootecnia

    1975-01-01

    Sera of 71 animals, divided in groups of males and females, in repose and after activity were studied. The method to establish the percentage of the /sup 125/I-lyothyronine retention in resin (Test /sup 125/I-T/sub 3/ or T/sub 3/) was modified by the use of 0.2 ml of serum on the resin column, after addition of the marked hormone. This modification served to prove that thoroughbred equines show binding of the I-lyothyronine to the serum four times reduced, indicating, therefore, that these animals have four times more ligation sites of triidothyronin saturation in the serum, when compared with the results obtained from human beings. The variance analysis applied to the T/sub 3/ Test showed no significant results at the 95% level as regards to activity. For the 71 animals, the author has found an average of 50.30% of the /sup 125/I-Lyothyronine in resin retention, being the confidence interval for this group between 48.75% and 51.85% to a 95% confidence coefficient. Evaluating the results of the T/sub 4/ Test by means of the variance analysis, we noticed that the male and female groups in repose differed statistically from the groups after activity to a 95% confidence coefficient. The author has grouped the results of the T/sub 4/ Test of 32 equines, 18 males and 14 females, in repose, obtaining an average of 0.61 mcg and 0.51 mcg and 0.71 mcg T/sub 4//100 ml as confidence interval to a 95% confidence coefficient. We have listed 39 results of T/sub 4/ Test, being 23 males and 61 Females, after activity, obtaining an average of 2.01 mcg of thyroxin by 100 ml of serum and 1.72 mcg and 2.30 T/sub 4//100 ml as confidence interval to a 95% confidence coefficient.

  5. Science Library of Test Items. Volume Thirteen. Mastery Testing Program. [Mastery Tests Series 5.] Tests M51-M65.

    Science.gov (United States)

    New South Wales Dept. of Education, Sydney (Australia).

    As part of a series of tests to measure mastery of specific skills in the natural sciences, copies of tests 51 through 65 include: (51) interpreting atomic and mass numbers; (52) extrapolating from a geological map; (53) matching geological sections and maps; (54) identifying parts of the human eye; (55) identifying the functions of parts of a…

  6. Patterns of informal reasoning in the context of socioscientific decision making

    Science.gov (United States)

    Sadler, Troy D.; Zeidler, Dana L.

    2005-01-01

    The purpose of this study is to contribute to a theoretical knowledge base through research by examining factors salient to science education reform and practice in the context of socioscientific issues. The study explores how individuals negotiate and resolve genetic engineering dilemmas. A qualitative approach was used to examine patterns of informal reasoning and the role of morality in these processes. Thirty college students participated individually in two semistructured interviews designed to explore their informal reasoning in response to six genetic engineering scenarios. Students demonstrated evidence of rationalistic, emotive, and intuitive forms of informal reasoning. Rationalistic informal reasoning described reason-based considerations; emotive informal reasoning described care-based considerations; and intuitive reasoning described considerations based on immediate reactions to the context of a scenario. Participants frequently relied on combinations of these reasoning patterns as they worked to resolve individual socioscientific scenarios. Most of the participants appreciated at least some of the moral implications of their decisions, and these considerations were typically interwoven within an overall pattern of informal reasoning. These results highlight the need to ensure that science classrooms are environments in which intuition and emotion in addition to reason are valued. Implications and recommendations for future research are discussed.

  7. Thermodynamic study of NaFe complex oxides. High temperature properties of Na sub 5 FeO sub 4 and Na sub 3 FeO sub 3

    CERN Document Server

    Furukawa, T

    2002-01-01

    In order to contribute the investigation into corrosion mechanism of the structural materials by leakage sodium, thermodynamic study of Na-Fe complex oxides formed by the reactions was carried out. Na sub 5 FeO sub 4 and Na sub 3 FeO sub 3 were used as the sample. Its high temperature properties (i.e. melting, solidification and transformation) were observed by Differential Scanning Calorimetry, DSC. Moreover, the original test named 'melting point confirmation test' was performed for the observation of traces of melting and solidification after the tests. Following contents have been obtained by this study. (1) Na sub 5 FeO sub 4 was stably as the solid without phase transformation and melting until 800degC. However, the compound was showing a tendency to change into Na sub 4 FeO sub 3 with temperature increasing under the low oxygen potential. (2) The stability of Na sub 3 FeO sub 3 is the same as that of Na sub 5 FeO sub 4 until 700degC. Over the temperature, the compound was changed differential compound ...

  8. Scientific reasoning abilities of nonscience majors in physics-based courses

    Science.gov (United States)

    Moore, J. Christopher; Rubbo, Louis J.

    2012-06-01

    We have found that non-STEM (science, technology, engineering, and mathematics) majors taking either a conceptual physics or astronomy course at two regional comprehensive institutions score significantly lower preinstruction on the Lawson’s Classroom Test of Scientific Reasoning (LCTSR) in comparison to national average STEM majors. Based on LCTSR score, the majority of non-STEM students can be classified as either concrete operational or transitional reasoners in Piaget’s theory of cognitive development, whereas in the STEM population formal operational reasoners are far more prevalent. In particular, non-STEM students demonstrate significant difficulty with proportional and hypothetico-deductive reasoning. Prescores on the LCTSR are correlated with normalized learning gains on various concept inventories. The correlation is strongest for content that can be categorized as mostly theoretical, meaning a lack of directly observable exemplars, and weakest for content categorized as mostly descriptive, where directly observable exemplars are abundant. Although the implementation of research-verified, interactive engagement pedagogy can lead to gains in content knowledge, significant gains in theoretical content (such as force and energy) are more difficult with non-STEM students. We also observe no significant gains on the LCTSR without explicit instruction in scientific reasoning patterns. These results further demonstrate that differences in student populations are important when comparing normalized gains on concept inventories, and the achievement of significant gains in scientific reasoning requires a reevaluation of the traditional approach to physics for non-STEM students.

  9. Scientific reasoning abilities of nonscience majors in physics-based courses

    Directory of Open Access Journals (Sweden)

    J. Christopher Moore

    2012-02-01

    Full Text Available We have found that non-STEM (science, technology, engineering, and mathematics majors taking either a conceptual physics or astronomy course at two regional comprehensive institutions score significantly lower preinstruction on the Lawson’s Classroom Test of Scientific Reasoning (LCTSR in comparison to national average STEM majors. Based on LCTSR score, the majority of non-STEM students can be classified as either concrete operational or transitional reasoners in Piaget’s theory of cognitive development, whereas in the STEM population formal operational reasoners are far more prevalent. In particular, non-STEM students demonstrate significant difficulty with proportional and hypothetico-deductive reasoning. Prescores on the LCTSR are correlated with normalized learning gains on various concept inventories. The correlation is strongest for content that can be categorized as mostly theoretical, meaning a lack of directly observable exemplars, and weakest for content categorized as mostly descriptive, where directly observable exemplars are abundant. Although the implementation of research-verified, interactive engagement pedagogy can lead to gains in content knowledge, significant gains in theoretical content (such as force and energy are more difficult with non-STEM students. We also observe no significant gains on the LCTSR without explicit instruction in scientific reasoning patterns. These results further demonstrate that differences in student populations are important when comparing normalized gains on concept inventories, and the achievement of significant gains in scientific reasoning requires a reevaluation of the traditional approach to physics for non-STEM students.

  10. Effects of junction resistance and counterelectrode material on point-contact tunneling into single- and polycrystalline YBa/sub 2/Cu/sub 3/O/sub 7-y/

    Energy Technology Data Exchange (ETDEWEB)

    Moog, E.R.; Hawley, M.E.; Gray, K.E.; Liu, J.Z.; Hinks, D.G.; Capone, D.W. II; Downey, J.

    1988-06-01

    The effects of junction resistance and counterelectrode material on the results of point-contact tunneling studies into single- and polycrystalline YBa/sub 2/Cu/sub 3/O/sub 7-y/ are illustrated. Although reasonably symmetric I(V) curves predominantly indicate energy gap values /Delta/ /approx/ 20 meV, large asymmetries are often found for high-resistance junctions. Very low-resistance junctions show the expected behavior of pure metallic bridge and indicate /Delta/ /approx/ 25-30 meV.

  11. Abstract Spatial Reasoning as an Autistic Strength

    Science.gov (United States)

    Stevenson, Jennifer L.; Gernsbacher, Morton Ann

    2013-01-01

    Autistic individuals typically excel on spatial tests that measure abstract reasoning, such as the Block Design subtest on intelligence test batteries and the Raven’s Progressive Matrices nonverbal test of intelligence. Such well-replicated findings suggest that abstract spatial processing is a relative and perhaps absolute strength of autistic individuals. However, previous studies have not systematically varied reasoning level – concrete vs. abstract – and test domain – spatial vs. numerical vs. verbal, which the current study did. Autistic participants (N = 72) and non-autistic participants (N = 72) completed a battery of 12 tests that varied by reasoning level (concrete vs. abstract) and domain (spatial vs. numerical vs. verbal). Autistic participants outperformed non-autistic participants on abstract spatial tests. Non-autistic participants did not outperform autistic participants on any of the three domains (spatial, numerical, and verbal) or at either of the two reasoning levels (concrete and abstract), suggesting similarity in abilities between autistic and non-autistic individuals, with abstract spatial reasoning as an autistic strength. PMID:23533615

  12. Improvement of the thermoplastic formability of Zr{sub 65}Cu{sub 17.5}Ni{sub 10}Al{sub 7.5} bulk metallic glass by minor addition of Erbium

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Q. [Shenzhen Key Laboratory of Special Functional Materials, College of Materials Science and Engineering, Shenzhen 518060 (China); Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060 (China); Zeng, X.R., E-mail: zengxier@szu.edu.cn [Shenzhen Key Laboratory of Special Functional Materials, College of Materials Science and Engineering, Shenzhen 518060 (China); Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060 (China); JANUS Precision Components Co., LTD., Dongguan 523000 (China); Fu, M.W., E-mail: mmmwfu@polyu.edu.hk [Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China); Chen, S.S. [Shenzhen Key Laboratory of Special Functional Materials, College of Materials Science and Engineering, Shenzhen 518060 (China); Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060 (China); Jiang, J. [Institute of Applied Physics, Jiangxi Academy of Sciences, Nanchang 330029 (China)

    2016-12-01

    The softness of Zr{sub 65}Cu{sub 17.5}Ni{sub 10}Al{sub 7.5} bulk metallic glass (BMG) in the super-cooled liquid range (SCLR) is obviously improved by minor addition of 2% Er, which makes (Zr{sub 65}Cu{sub 17.5}Ni{sub 10}Al{sub 7.5}){sub 98}Er{sub 2} (Zr65Er2) to be a very formable Be-free Zr-based BMG. It is found the lower glass transition temperature of Zr65Er2 has an important contribution to the improvement of formability, which is contrary to the general understanding that the larger fragility and wider super-cooled liquid region (SCLR) are the major reasons for better thermoplastic formability. This finding is well explained by using the linear simplification of the SCLR in Angell plot. Zr65Er2 also has lower crystallization temperature and melting temperature, which is believed to be related to the formation of short-range ordering with lower transition energy rather than the composition shift to near eutectic. The above results help understand the effect of minor addition of rare-earth to the formability of Zr-based bulk metallic glasses.

  13. Triple energy correlations: A new method of α/sub S//sub x/ determination in high energy e/sup +/e/sup -/ annihilation

    International Nuclear Information System (INIS)

    Csikor, F.; Eszes, G.; Garrido, L.; Pocsik, G.

    1987-01-01

    Reasons why planar triple energy correlation measurement may serve as an appropriate method of α/sub S/ determination are reviewed. The new MARKJ results on α/sub S/ determination are briefly summarized

  14. Study on service test procedure for SMES systems

    Energy Technology Data Exchange (ETDEWEB)

    Ren, L., E-mail: rl8868@126.co [R and D Center of Applied Superconductivity, Huazhong University of Science and Technology, Wuhan 430074 (China); Tang, Y.; Li, J.; Shi, J. [R and D Center of Applied Superconductivity, Huazhong University of Science and Technology, Wuhan 430074 (China); Hu, Y. [State Grid Electric Power Research Institute, Wuhan 430074 (China); Guo, F.; Chen, L.; Cheng, S. [R and D Center of Applied Superconductivity, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2009-10-15

    Some superconducting magnetic energy storage (SMES) systems have been developed successfully, and the function of them was verified by experiment. Considering the impact on the system security and stability when they are connected to the power system, it is important to build a standard test procedure and propose the main experimental contents for some representative superconducting devices. Based on the experimental results of a 35 kJ/7 kW conduction-cooled high-T{sub c} SMES system, which was developed by Huazhong University of Science and Technology, the test items and methods for a conduction-cooled high-T{sub c} SMES system are studied. For performance evaluation of this high-T{sub c} SMES, three superconducting magnet performance tests, power conditioning characteristic test and dynamic experiment in a simulated power system were fulfilled.

  15. Lattice parameters and Raman-active phonon modes of β-(Al{sub x}Ga{sub 1−x}){sub 2}O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Kranert, Christian, E-mail: christian.kranert@uni-leipzig.de; Jenderka, Marcus; Lenzner, Jörg; Lorenz, Michael; Wenckstern, Holger von; Schmidt-Grund, Rüdiger; Grundmann, Marius [Institut für Experimentelle Physik II, Universität Leipzig, Halbleiterphysik, Linnéstr. 5, 04103 Leipzig (Germany)

    2015-03-28

    We present X-ray diffraction and Raman spectroscopy investigations of a (100)-oriented (Al{sub x}Ga{sub 1–x}){sub 2}O{sub 3} thin film on MgO (100) and bulk-like ceramics in dependence on their composition. The thin film grown by pulsed laser deposition has a continuous lateral composition spread allowing to determine precisely the dependence of the phonon mode properties and lattice parameters on the chemical composition. For x < 0.4, we observe the single-phase β-modification. Its lattice parameters and phonon energies depend linearly on the composition. We determined the slopes of these dependencies for the individual lattice parameters and for nine Raman lines, respectively. While the lattice parameters of the ceramics follow Vegard's rule, deviations are observed for the thin film. This deviation has only a small effect on the phonon energies, which show a reasonably good agreement between thin film and ceramics.

  16. AOI [3] High-Temperature Nano-Derived Micro-H<sub>2sub> and - H<sub>2sub>S Sensors

    Energy Technology Data Exchange (ETDEWEB)

    Sabolsky, Edward M. [West Virginia Univ., Morgantown, WV (United States)

    2014-08-01

    Tech assisted in the testing of the sensors in syngas with contaminate levels of H<sub>2sub>S. The idea of including nanomaterials as the sensing material within resistive-type chemical sensor platforms was to increase the sensitivity (as shown for room temperature applications). Unfortunately, nanomaterials are not stable at high temperatures due to sintering and coarsening processes that are driven by their high surface to volume ratio. Therefore, new hydrogen and sulfur selective nanomaterial systems with high selectivity and stability properties in the proposed harsh environment were investigated. Different nano-morphologies of zirconate, molybdate, and tungstate compounds were investigated. The fabrication of the microsensors consisted of the deposition of the selective nanomaterial systems over metal based interconnects on an inert substrate. This work utilized the chemi-resistive (resistive- type) microsensor architecture where the chemically and structurally stable, high temperature compatible electrodes were sputtered onto a ceramic substrate. The nanomaterial sensing systems were deposited over the electrodes using a lost mold method patterned by conventional optical lithography. The microsensor configuration with optimized nanomaterial system was tested and compared to a millimeter-size sensor e outcomes of this research will contribute to the economical application of sensor arrays for simultaneous sensing of H<sub>2sub>, H<sub>2sub>S, and SO<sub>2sub>.

  17. MnCo{sub 2}O{sub 4} spinel chromium barrier coatings for SOFC interconnect by HVOF

    Energy Technology Data Exchange (ETDEWEB)

    Lagerbom, J.; Varis, T.; Pihlatie, M.; Himanen, O.; Saarinen, V.; Kiviaho, J.; Turunen, E. [VTT Technical Research Centre of Finland, Espoo (Finland); Puranen, J. [Tampere Univ. of Technology (Finland). Inst. of Materials Science

    2010-07-01

    Chromia released from steel parts used for interconnect plates by evaporation and condensation can quickly degrade the cell (cathode) performance in solid oxide fuel cell SOFC. Coatings on top of the IC plate can work as a chromium evaporation barrier. The coating material should have good electrical conductivity, high temperature stability and nearly the same coefficient of thermal expansion as the cell materials. One candidate for the coating material is MnCo{sub 2}O{sub 4} spinel because of its suitable properties. High velocity oxy fuel (HVOF) spraying was used for the coating application on Crofer 22 APU steel samples. Using commercial and self made spray dried powders together with an HV2000 spray gun it was possible to successfully manufacture, well adhering, dense and reasonably uniform coatings. The samples were tested in oxidation exposure tests in air followed by post analysis in SEM. Powders and coatings microstructures are presented here, both before and after exposure. It was found out that together with spraying parameters the powder characteristics used influence clearly to the coating quality. Especially as very thin coatings was aimed with dense structure fine powders was found to be essential. (orig.)

  18. Fake gaps in AdS{sub 3}/CFT{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Belin, Alexandre [Department of Physics, Stanford University,Stanford, CA 94305-4060 (United States); Castro, Alejandra [Institute for Theoretical Physics, University of Amsterdam,Science Park 904, Postbus 94485, 1090 GL Amsterdam (Netherlands); Hung, Ling-Yan [Department of Physics and Center for Field Theory and Particle Physics, Fudan University,220 Handan Road, 200433 Shanghai (China); Collaborative Innovation Center of Advanced Microstructures, Fudan University,220 Handan Road, 200433 Shanghai (China)

    2015-11-23

    We discuss properties of interpolating geometries in three dimensional gravity in the presence of a chiral anomaly. This anomaly, which introduces an unbalance between left and right central charges, is protected under RG flows. For this simple reason it is impossible to gap a system with such an anomaly. Our goal is to discuss how holography captures this basic and robust feature. We demonstrate the absence of a mass gap by analysing the linearized spectrum and holographic entanglement entropy of these backgrounds in the context of AdS{sub 3}/CFT{sub 2}.

  19. Science Library of Test Items. Volume Twelve. Mastery Testing Programme. [Mastery Tests Series 4.] Tests M39-M50.

    Science.gov (United States)

    New South Wales Dept. of Education, Sydney (Australia).

    As part of a series of tests to measure mastery of specific skills in the natural sciences, copies of tests 39 through 50 include: (39) using a code; (40) naming the parts of a microscope; (41) calculating density and predicting flotation; (42) estimating metric length; (43) using SI symbols; (44) using s=vt; (45) applying a novel theory; (46)…

  20. Electronic and structural properties of {beta}-Be{sub 3}N{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Mokhtari, A.; Akbarzadeh, H

    2002-12-01

    We report the results of a theoretical study of the electronic and structural properties of the hexagonal beryllium nitride, using first principle pseudopotential plane wave (PP-PW) as well as full potential linearized augmented plane wave (FP-LAPW) methods within density functional theory. In the case of PP-PW we generated the pseudopotential by the highly optimized Q{sub c}-tuning method and used the local density approximation and generalized gradient approximation (GGA) for the exchange-correlation potential. We applied pressure on the unit cell by the Wentzcovitch and traditional methods. In the FP-LAPW approach only the GGA was used for the exchange-correlation potential. Our calculated values for structural properties, based on both approaches are in reasonable agreement with experimental and other theoretical (Hartree Fock) results. By applying the above two approaches and also the Tight Binding Linear Muffin Thin Orbital method, the ground state Kohn-Sham eigenvalues were calculated. The energy bands in three cases were similar and except for the energy gap values they were in good agreement with other theoretical results. Various versions of GGA functionals are usually obtained by optimizing the exchange correlation energy E{sub XC} rather than the corresponding potential V{sub XC}. As these functionals are not able to simultaneously reproduce E{sub XC} and V{sub XC}, hence they cannot obtain an accurate value for the band gap which mainly depends on the potential. Engel and Vosko (Phys. Rev. B 47 (1993) 13164) have proposed an alternate form of GGA which is based on optimizing V{sub XC} instead of the integral quantity E{sub XC}. We used this functional to calculate the band gap and the result seems to be more reasonable. Finally the total and partial densities of states were calculated for each atom.

  1. What Role Do Masculine Norms Play in Men's HIV Testing in Sub-Saharan Africa?: A Scoping Review.

    Science.gov (United States)

    Sileo, Katelyn M; Fielding-Miller, Rebecca; Dworkin, Shari L; Fleming, Paul J

    2018-05-18

    Men living with HIV/AIDS in sub-Saharan Africa are less likely to test for HIV than women. We conducted a scoping review in May of 2016 to identify how masculine norms influence men's HIV testing in sub-Saharan Africa. Our review yielded a total of 13 qualitative studies from 8 countries. Masculine norms create both barriers and facilitators to HIV testing. Barriers included emotional inexpression, gendered communication, social pressures to be strong and self-reliant, and the fear that an HIV positive result would threaten traditional social roles (i.e., husband, father, provider, worker) and reduce sexual success with women. Facilitators included perceptions that HIV testing could restore masculinity through regained physical strength and the ability to re-assume the provider role after accessing treatment. Across sub-Saharan Africa, masculinity appears to play an important role in men's decision to test for HIV and further research and interventions are needed to address this link.

  2. A critical narrative review of transfer of basic science knowledge in health professions education.

    Science.gov (United States)

    Castillo, Jean-Marie; Park, Yoon Soo; Harris, Ilene; Cheung, Jeffrey J H; Sood, Lonika; Clark, Maureen D; Kulasegaram, Kulamakan; Brydges, Ryan; Norman, Geoffrey; Woods, Nicole

    2018-02-08

    'Transfer' is the application of a previously learned concept to solve a new problem in another context. Transfer is essential for basic science education because, to be valuable, basic science knowledge must be transferred to clinical problem solving. Therefore, better understanding of interventions that enhance the transfer of basic science knowledge to clinical reasoning is essential. This review systematically identifies interventions described in the health professions education (HPE) literature that document the transfer of basic science knowledge to clinical reasoning, and considers teaching and assessment strategies. A systematic search of the literature was conducted. Articles related to basic science teaching at the undergraduate level in HPE were analysed using a 'transfer out'/'transfer in' conceptual framework. 'Transfer out' refers to the application of knowledge developed in one learning situation to the solving of a new problem. 'Transfer in' refers to the use of previously acquired knowledge to learn from new problems or learning situations. Of 9803 articles initially identified, 627 studies were retrieved for full text evaluation; 15 were included in the literature review. A total of 93% explored 'transfer out' to clinical reasoning and 7% (one article) explored 'transfer in'. Measures of 'transfer out' fostered by basic science knowledge included diagnostic accuracy over time and in new clinical cases. Basic science knowledge supported learning - 'transfer in' - of new related content and ultimately the 'transfer out' to diagnostic reasoning. Successful teaching strategies included the making of connections between basic and clinical sciences, the use of commonsense analogies, and the study of multiple clinical problems in multiple contexts. Performance on recall tests did not reflect the transfer of basic science knowledge to clinical reasoning. Transfer of basic science knowledge to clinical reasoning is an essential component of HPE that

  3. Scientific reasoning skills development in the introductory biology courses for undergraduates

    Science.gov (United States)

    Schen, Melissa S.

    Scientific reasoning is a skill of critical importance to those students who seek to become professional scientists. Yet, there is little research on the development of such reasoning in science majors. In addition, scientific reasoning is often investigated as two separate entities: hypothetico-deductive reasoning and argumentation, even though these skills may be linked. With regard to argumentation, most investigations look at its use in discussing socioscientific issues, not in analyzing scientific data. As scientists often use the same argumentation skills to develop and support conclusions, this avenue needs to be investigated. This study seeks to address these issues and establish a baseline of both hypothetico-deductive reasoning and argumentation of scientific data of biology majors through their engagement in introductory biology coursework. This descriptive study investigated the development of undergraduates' scientific reasoning skills by assessing them multiple times throughout a two-quarter introductory biology course sequence for majors. Participants were assessed at the beginning of the first quarter, end of the first quarter, and end of the second quarter. A split-half version of the revised Lawson Classroom Test of Scientific Reasoning (LCTSR) and a paper and pencil argumentation instrument developed for this study were utilized to assess student hypothetico-deductive reasoning and argumentation skills, respectively. To identify factors that may influence scientific reasoning development, demographic information regarding age, gender, science coursework completed, and future plans was collected. Evidence for course emphasis on scientific reasoning was found in lecture notes, assignments, and laboratory exercises. This study did not find any trends of improvement in the students' hypothetico-deductive reasoning or argumentation skills either during the first quarter or over both quarters. Specific difficulties in the control of variables and

  4. The script concordance test in radiation oncology: validation study of a new tool to assess clinical reasoning

    International Nuclear Information System (INIS)

    Lambert, Carole; Gagnon, Robert; Nguyen, David; Charlin, Bernard

    2009-01-01

    The Script Concordance test (SCT) is a reliable and valid tool to evaluate clinical reasoning in complex situations where experts' opinions may be divided. Scores reflect the degree of concordance between the performance of examinees and that of a reference panel of experienced physicians. The purpose of this study is to demonstrate SCT's usefulness in radiation oncology. A 90 items radiation oncology SCT was administered to 155 participants. Three levels of experience were tested: medical students (n = 70), radiation oncology residents (n = 38) and radiation oncologists (n = 47). Statistical tests were performed to assess reliability and to document validity. After item optimization, the test comprised 30 cases and 70 questions. Cronbach alpha was 0.90. Mean scores were 51.62 (± 8.19) for students, 71.20 (± 9.45) for residents and 76.67 (± 6.14) for radiation oncologists. The difference between the three groups was statistically significant when compared by the Kruskall-Wallis test (p < 0.001). The SCT is reliable and useful to discriminate among participants according to their level of experience in radiation oncology. It appears as a useful tool to document the progression of reasoning during residency training

  5. How People Reason: A Grounded Theory Study of Scientific Reasoning about Global Climate Change

    Science.gov (United States)

    Liu, Shiyu

    Scientific reasoning is crucial in both scientific inquiry and everyday life. While the majority of researchers have studied "how people reason" by focusing on their cognitive processes, factors related to the underpinnings of scientific reasoning are still under-researched. The present study aimed to develop a grounded theory that captures not only the cognitive processes during reasoning but also their underpinnings. In particular, the grounded theory and phenomenographic methodologies were integrated to explore how undergraduate students reason about competing theories and evidence on global climate change. Twenty-six undergraduate students were recruited through theoretical sampling. Constant comparative analysis of responses from interviews and written assessments revealed that participants were mostly drawn to the surface features when reasoning about evidence. While prior knowledge might not directly contribute to participants' performance on evidence evaluation, it affected their level of engagement when reading and evaluating competing arguments on climate issues. More importantly, even though all participants acknowledged the relative correctness of multiple perspectives, they predominantly favored arguments that supported their own beliefs with weak scientific reasoning about the opposing arguments. Additionally, factors such as personal interests, religious beliefs, and reading capacity were also found to have bearings on the way participants evaluated evidence and arguments. In all, this work contributes to the current endeavors in exploring the nature of scientific reasoning. Taking a holistic perspective, it provides an in-depth discussion of factors that may affect or relate to scientific reasoning processes. Furthermore, in comparison with traditional methods used in the literature, the methodological approach employed in this work brought an innovative insight into the investigation of scientific reasoning. Last but not least, this research may

  6. Hall mobilities in GaN{sub x}As{sub 1-x}

    Energy Technology Data Exchange (ETDEWEB)

    Olea, Javier; Gonzalez-Diaz, German [Dpto. de Fisica Aplicada III, Facultad de Ciencias Fisicas, Universidad Complutense de Madrid, Madrid 28040 (Spain); Yu, Kin Man; Walukiewicz, Wladek [Materials Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720-8197 (United States)

    2010-07-15

    In this work we report a systematic study of the electron and hole mobilities of GaN{sub x}As{sub 1-x} alloys with different dopants (Zn, Te) and carrier concentrations (10{sup 17}-10{sup 19} cm{sup -3}). We found a very slight reduction of the hole mobility in p-GaN{sub x}As{sub 1-x} compared to p-GaAs, indicating that for small N contents ({proportional_to}1.6%) the valence band is not affected by the N incorporation. In a striking contrast, incorporation of even small amounts of N leads to an abrupt reduction of the electron mobility in n-GaN{sub x}As{sub 1-x}. We further show that the processes that limit the mobility in GaN{sub x}As{sub 1-x} can be explained by the band broadening and the random field scatterings. Considering these two scattering mechanisms we calculated the dependence of electron mobilities on electron concentration as well as on N composition in GaN{sub x}As{sub 1-x}. The calculations agree reasonably well with experiment data of maximum electron mobilities with alloy composition. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  7. A new magnet material with ThMn{sub 12} structure: (Nd{sub 1−x}Zr{sub x})(Fe{sub 1−y}Co{sub y}){sub 11+z}Ti{sub 1−z}N{sub α} (α=0.6–1.3)

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, S.; Kuno, T.; Urushibata, K. [Shizuoka Institute of Science and Technology, 2200-2 Toyosawa, Fukuroi, Shizuoka 437-8555 (Japan); Kobayashi, K., E-mail: koba@ms.sist.ac.jp [Shizuoka Institute of Science and Technology, 2200-2 Toyosawa, Fukuroi, Shizuoka 437-8555 (Japan); Sakuma, N.; Washio, K.; Yano, M.; Kato, A.; Manabe, A. [Toyota Mortor Corporation, 1 Toyota-cho, Toyota 471-8572, Aichi (Japan)

    2016-03-01

    We previously reported a new compound for permanent magnets, (Nd{sub 0.7}Zr{sub 0.3})(Fe{sub 0.75}Co{sub 0.25}){sub 11.5}Ti{sub 0.5}N{sub 0.56}, which has a high saturation polarization (J{sub s}) of 1.68 T and a high magnetocrystalline anisotropy field (H{sub a}) of 2.88–4.0 MA/m. Here, we examined the effects of substituting Co and Ti at the Fe sites and Zr at the Nd sites. J{sub s} increased with Co substitution at the Fe sites, and higher Fe and Co content could be achieved by decreasing the Ti content to −Ti{sub 0.5}. The ThMn{sub 12} structure with high Fe and Co content (i.e. low Ti content) was stabilized mainly by −Zr{sub 0.3} substitution at the Nd sites. The Zr substitution resolves the local mismatch in atomic size in the structure. Specifically, the atomic radius of Zr is about 88% that of Nd, so the local structure surrounding Nd (2a site) shrinks as a result of the substitution and resolves the size mismatch in the three types of local Fe six-fold symmetric hexagons in the structure. The effect of the α-(Fe, Co) phase on J{sub s} was evaluated from the phase's volume fraction measurement of 7.7% (8.1 wt%) by electron backscatter diffraction. Nitrogenation of the starting alloy also resulted in augmentation of the c-axis magnetocrystalline anisotropy. Finally, we confirmed a high J{sub s}(−N{sub 1.3}) of 1.71T (=1.67 T, −0.04 T for the α-(Fe, Co) phase) and H{sub a} of 2.9–5.25 MA/m (H{sub a}(−N{sub 1.3})=5.25 MA/m) in the (Nd{sub 0.7}Zr{sub 0.3})(Fe{sub 0.75}Co{sub 0.25}){sub 11.5}Ti{sub 0.5}N{sub α} (α=0.60–1.30) compounds. - Highlights: • We found a new compound of composition of (Nd,Zr)(Fe,Co){sub 11.5}Ti{sub 0.5}N{sub x} (x=0.6–1.3). • The compound shows high saturation polarization of 1.67T. • The Curie temperature of compound is above 840K, and anisotropy field is nearly 6.6 T. • The basic physical properties such as inner fields of each Fe site were measured. • The reasons of stabilization of 1–12

  8. Preparation and characterization of Au/CeO{sub 2}-Al{sub 2}O{sub 3} monoliths

    Energy Technology Data Exchange (ETDEWEB)

    Gawel, Bartlomiej; Lambrechts, Kalle [Ugelstad Laboratory, Department of Chemical Engineering, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim (Norway); Oye, Gisle, E-mail: gisle.oye@chemeng.ntnu.no [Ugelstad Laboratory, Department of Chemical Engineering, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim (Norway)

    2012-05-15

    Highlights: Black-Right-Pointing-Pointer A facile method for preparing Au/CeO{sub 2}-Al{sub 2}O{sub 3} monoliths with hierarchical porosity. Black-Right-Pointing-Pointer Continuous-flow testing of the monoliths in liquid-phase oxidation of glucose. Black-Right-Pointing-Pointer Increased catalytic activity in the presence of cerium oxide (stirred-batch tests). - Abstract: Porous CeO{sub 2}-Al{sub 2}O{sub 3} monoliths with hierarchical pore structure were prepared by mixing boehmite particles with solutions containing different amounts of cerium chloride and aluminum nitrate. The monoliths were functionalized with gold nanoparticles using the incipient wetness method. The resulting materials were characterized by X-ray diffraction, nitrogen sorption, mercury porosimetry, UV-vis spectroscopy and transmission electron microscopy. The catalysts were tested in liquid phase glucose oxidation, comparing continuously stirred batch reactor and continuous-flow fix-bed reactor setups.

  9. Systematic Testing should not be a Topic in the Computer Science Curriculum!

    DEFF Research Database (Denmark)

    Christensen, Henrik Bærbak

    2003-01-01

    In this paper we argue that treating "testing" as an isolated topic is a wrong approach in computer science and software engineering teaching. Instead testing should pervade practical topics and exercises in the computer science curriculum to teach students the importance of producing software...

  10. Superconducting properties of Ca{sub 1−x}RE{sub x}Fe{sub 2}As{sub 2} (RE: Rare Earths)

    Energy Technology Data Exchange (ETDEWEB)

    Tamegai, T., E-mail: tamegai@ap.t.u-tokyo.ac.jp [Department of Applied Physics, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); JST, Transformative Research-Project on Iron Pnictides (TRIP), Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Ding, Q.P. [Department of Applied Physics, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); JST, Transformative Research-Project on Iron Pnictides (TRIP), Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Ishibashi, T. [Department of Applied Physics, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Nakajima, Y. [Department of Applied Physics, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); JST, Transformative Research-Project on Iron Pnictides (TRIP), Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)

    2013-01-15

    Highlights: ► Superconducting properties in rare-earth doped CaFe{sub 2}As{sub 2} single crystals are characterized. ► Sharp resistive transitions with small anisotropy parameter of ∼1.75 are observed. ► Average critical current density is much smaller than other iron-based superconductors. ► Magneto-optical imaging confirms very inhomogeneous superconducting state. -- Abstract: We have grown rare-earth doped CaFe{sub 2}As{sub 2} single crystals and characterized their normal and superconducting properties. Temperature dependence of resistivity and its absolute value suggest good metallic conduction, suppressing antiferromagnetic (AF) transition in the undoped sample. Hall coefficient shows little temperature dependence, consistent with the suppression AF state. Superconducting transitions characterized by resistivity drops in magnetic fields for both parallel to c-axis and ab-plane are reasonably sharp with a weak anisotropy parameter ∼1.75. Despite these observations, average critical current density estimated from the bulk magnetization is orders of magnitude smaller than other typical iron-based superconductors. Magneto-optical imaging confirms very inhomogeneous superconducting state.

  11. Beyond ‘test and treat’ – malaria diagnosis for improved pediatric fever management in sub-Saharan Africa

    Science.gov (United States)

    Johansson, Emily White

    2016-01-01

    Background Malaria rapid diagnostic tests (RDTs) have great potential to improve quality care and rational drug use in malaria-endemic settings although studies have shown common RDT non-compliance. Yet, evidence has largely been derived from limited hospital settings in few countries. This article reviews a PhD thesis that analyzed national surveys from multiple sub-Saharan African countries to generate large-scale evidence of malaria diagnosis practices and its determinants across different contexts. Design A mixed-methods approach was used across four studies that included quantitative analysis of national household and facility surveys conducted in multiple sub-Saharan African countries at the outset of new guidelines (Demographic and Health Surveys and Service Provision Assessments). Qualitative methods were used to explore reasons for quantitative findings in select settings. Results There was low (17%) and inequitable test uptake across 13 countries in 2009–2011/12, with greater testing at hospitals than at peripheral clinics (odds ratio [OR]: 0.62, 95% confidence interval [CI]: 0.56–0.69) or community health workers (OR: 0.31, 95% CI: 0.23–0.43) (Study I). Significant variation was found in the effect of diagnosis on antimalarial use at the population level across countries (Uganda OR: 0.84, 95% CI: 0.66–1.06; Mozambique OR: 3.54, 95% CI: 2.33–5.39) (Study II). A Malawi national facility census indicated common compliance to malaria treatment guidelines (85% clients with RDT-confirmed malaria prescribed first-line treatment), although other fever assessments were not often conducted and there was poor antibiotic targeting (59% clients inappropriately prescribed antibiotics). RDT-negative patients had 16.8 (95% CI: 8.6–32.7) times higher odds of antibiotic overtreatment than RDT-positive patients conditioned by cough or difficult breathing complaints (Study III). In Mbarara (Uganda), health workers reportedly prescribed antimalarials to RDT

  12. Beyond ‘test and treat’ – malaria diagnosis for improved pediatric fever management in sub-Saharan Africa

    Directory of Open Access Journals (Sweden)

    Emily White Johansson

    2016-12-01

    Full Text Available Background: Malaria rapid diagnostic tests (RDTs have great potential to improve quality care and rational drug use in malaria-endemic settings although studies have shown common RDT non-compliance. Yet, evidence has largely been derived from limited hospital settings in few countries. This article reviews a PhD thesis that analyzed national surveys from multiple sub-Saharan African countries to generate large-scale evidence of malaria diagnosis practices and its determinants across different contexts. Design: A mixed-methods approach was used across four studies that included quantitative analysis of national household and facility surveys conducted in multiple sub-Saharan African countries at the outset of new guidelines (Demographic and Health Surveys and Service Provision Assessments. Qualitative methods were used to explore reasons for quantitative findings in select settings. Results: There was low (17% and inequitable test uptake across 13 countries in 2009–2011/12, with greater testing at hospitals than at peripheral clinics (odds ratio [OR]: 0.62, 95% confidence interval [CI]: 0.56–0.69 or community health workers (OR: 0.31, 95% CI: 0.23–0.43 (Study I. Significant variation was found in the effect of diagnosis on antimalarial use at the population level across countries (Uganda OR: 0.84, 95% CI: 0.66–1.06; Mozambique OR: 3.54, 95% CI: 2.33–5.39 (Study II. A Malawi national facility census indicated common compliance to malaria treatment guidelines (85% clients with RDT-confirmed malaria prescribed first-line treatment, although other fever assessments were not often conducted and there was poor antibiotic targeting (59% clients inappropriately prescribed antibiotics. RDT-negative patients had 16.8 (95% CI: 8.6–32.7 times higher odds of antibiotic overtreatment than RDT-positive patients conditioned by cough or difficult breathing complaints (Study III. In Mbarara (Uganda, health workers reportedly prescribed antimalarials to

  13. A neural model of rule generation in inductive reasoning.

    Science.gov (United States)

    Rasmussen, Daniel; Eliasmith, Chris

    2011-01-01

    Inductive reasoning is a fundamental and complex aspect of human intelligence. In particular, how do subjects, given a set of particular examples, generate general descriptions of the rules governing that set? We present a biologically plausible method for accomplishing this task and implement it in a spiking neuron model. We demonstrate the success of this model by applying it to the problem domain of Raven's Progressive Matrices, a widely used tool in the field of intelligence testing. The model is able to generate the rules necessary to correctly solve Raven's items, as well as recreate many of the experimental effects observed in human subjects. Copyright © 2011 Cognitive Science Society, Inc.

  14. Mn-Na{sub 2}WO{sub 4}/SiO{sub 2}. An industrial catalyst for methane coupling?

    Energy Technology Data Exchange (ETDEWEB)

    Yildiz, M.; Arndt, S.; Otremba, T.; Thomas, A.; Schomaeker, R. [Technische Univ. Berlin (Germany). Dept. of Chemistry; Simon, U.; Berthold, A.; Goerke, O.; Schubert, H. [Technische Univ. Berlin (Germany). Dept. of Materials Science; Aksu, Y. [Akdeniz Univ. (Turkey). Dept. of Material Science and Engineering

    2012-07-01

    The oxidative coupling of methane (OCM) is one of the best reactions for the direct conversion of methane. Despite all efforts, a suitable OCM process has not been put into practice yet, due to a lack of active, selective and stable catalyst. Mn-Na{sub 2}WO{sub 4}/SiO{sub 2} has attracted great interest because of its proven long term stability and its highly suitable catalytic performance. In spite of the large number of studies on this catalyst, structural characterizations are very difficult due to its complex trimetallic and multiphase nature. Previously, we studied a broad variety of support materials for the Mn-Na{sub 2}WO{sub 4}/SiO{sub 2} catalyst, e.g. Al{sub 2}O{sub 3}, TiO{sub 2}, ZrO{sub 2} and MgO. We found that SiO{sub 2} is the most suitable support material. A variation of the SiO{sub 2} materials showed that the catalytic performance does not differ substantially. However, the performance of SBA-15 supported Mn-Na{sub 2}WO{sub 4} catalyst was outstanding in comparison to all other silica supported catalysts. The reason of this substantial increase in the activity could be the ordered mesoporous structure of its support material. To understand the reaction mechanism, the kinetic isotope effect (KIE) with CD{sub 4} over Mn-Na{sub 2}WO{sub 4}/SiO{sub 2} was studied, we found that the consecutive oxidation of the C{sub 2} products is an important constraint as described in the literature for other catalysts. In order to apply this catalyst in a miniplant, we developed an upscaled preparation procedure via a fluidized bed granulation, allowing the preparation of large amounts of this catalyst. (orig.)

  15. Alkali/TX{sub 2} catalysts for CO/H{sub 2} conversion to C{sub 1}-C{sub 4} alcohols. Technical progress report, March 1989--August 1989

    Energy Technology Data Exchange (ETDEWEB)

    Klier, K.; Herman, R.G.; Bastian, R.D.; Flanagan, K.L.

    1989-12-31

    Ruthenium disulfide catalysts have been synthesized, tested, and characterized during this period of research. It was observed that both the undoped and Cs-doped RuS{sub 2} catalysts produced alcohols and lower amounts of hydrocarbons from H{sub 2}/CO = 1.0 synthesis gas at temperatures above 300{degree}C. Calcination and catalytic testing resulted in partial reduction of the RuS{sub 2} to Ru{sup o}. Calcination under H{sub 2}S prevented the partial reduction of the RuS{sub 2} catalyst, but subsequent catalytic testing again resulted in the formation of a quantity of Ru{sup o}. A Cs-doped RuS{sub 2} catalyst was prepared, but it might have had too high of a loading of Cs. Upon testing, a lower activity was observed for the doped catalyst compared with the undoped catalyst, but the alcohol selectivity was the same for the two catalysts.

  16. What is the role of induction and deduction in reasoning and scientific inquiry?

    Science.gov (United States)

    Lawson, Anton E.

    2005-08-01

    A long-standing and continuing controversy exists regarding the role of induction and deduction in reasoning and in scientific inquiry. Given the inherent difficulty in reconstructing reasoning patterns based on personal and historical accounts, evidence about the nature of human reasoning in scientific inquiry has been sought from a controlled experiment designed to identify the role played by enumerative induction and deduction in cognition as well as from the relatively new field of neural modeling. Both experimental results and the neurological models imply that induction across a limited set of observations plays no role in task performance and in reasoning. Therefore, support has been obtained for Popper's hypothesis that enumerative induction does not exist as a psychological process. Instead, people appear to process information in terms of increasingly abstract cycles of hypothetico-deductive reasoning. Consequently, science instruction should provide students with opportunities to generate and test increasingly complex and abstract hypotheses and theories in a hypothetico-deductive manner. In this way students can be expected to become increasingly conscious of their underlying hypothetico-deductive thought processes, increasingly skilled in their application, and hence increasingly scientifically literate.

  17. Sampling, Probability Models and Statistical Reasoning Statistical

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 5. Sampling, Probability Models and Statistical Reasoning Statistical Inference. Mohan Delampady V R Padmawar. General Article Volume 1 Issue 5 May 1996 pp 49-58 ...

  18. Similarities of theoretical and practical reasoning processes : behavioral and brain imaging evidences

    OpenAIRE

    Wiedenmann, Patrick

    2009-01-01

    For hundreds of years, philosophers explored how humans reason and what reasoning abilities humans possess. They were also interested at how these reasoning abilities could and should be applied to reach a peaceful and flourishing coexistence. The two sub-disciplines investigating these issues are theoretical and practical philosophy. Epistemology is the main research domain of the former, whereas morals and ethics represent the main research field of the latter. Philosophers like Kant often ...

  19. Preparation of transparent Cu{sub 2}Y{sub 2}O{sub 5} thin films by RF magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Chiu, Te-Wei, E-mail: tewei@ntut.edu.tw; Chang, Chih-Hao; Yang, Li-Wei; Wang, Yung-Po

    2015-11-01

    Highlights: • Cu{sub 2}Y{sub 2}O{sub 5} thin films were prepared by RF magnetron sputtering. • Cu{sub 2}Y{sub 2}O{sub 5} thin films have high transmittance and antibacterial properties. • Mechanical properties of Cu{sub 2}Y{sub 2}O{sub 5} thin films were investigated. - Abstract: Cu{sub 2}Y{sub 2}O{sub 5} thin films were deposited on non-alkali glass substrates by RF magnetron sputtering. Its crystal structure, microstructure, optical property, mechanical property, and antibacterial activity were investigated by grazing-incidence X-ray diffraction, transmittance spectra, nanoindenter, and antibiotics test, respectively. A single-phase of Cu{sub 2}Y{sub 2}O{sub 5} was obtained while annealing at 700 °C in air and its optical transparency was >80% in the visible region. The hardness and elastic modulus of the film were 6.7 GPa and 82 GPa, respectively. Antibiotics testing result revealed that Cu{sub 2}Y{sub 2}O{sub 5} surface had a superior antibacterial performance even at a dark environment. Therefore, Cu{sub 2}Y{sub 2}O{sub 5} is a promising novel transparent antibacterial hard coating material.

  20. First-principles investigations on the electronic structures of U{sub 3}Si{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Tong [College of Information & Communication, Harbin Engineering University, Harbin, 150001 (China); Qiu, Nianxiang [Engineering Laboratory of Specialty Fibers and Nuclear Energy Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang, 315201 (China); Wen, Xiaodong [State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, P.O. Box 165, Taiyuan, Shanxi, 030001 (China); Synfuels China, 100195 (China); Tian, Yonghui [College of Life Science, Sichuan University, Chengdu, Sichuan, 610064 (China); He, Jian [Center for Translational Medicine, Department of Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023 (China); Luo, Kan; Zha, Xianhu; Zhou, Yuhong; Huang, Qing; Lang, Jiajian [Engineering Laboratory of Specialty Fibers and Nuclear Energy Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang, 315201 (China); Du, Shiyu, E-mail: dushiyu@nimte.ac.cn [Engineering Laboratory of Specialty Fibers and Nuclear Energy Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang, 315201 (China)

    2016-02-15

    U{sub 3}Si{sub 2} has been widely utilized as a high-power uranium fuel for research reactors due to its high density of uranium. However, theoretical investigations on this material are still scarce up to now. For this reason, the computational study via density functional theory (DFT) is performed on the U{sub 3}Si{sub 2} compound in this work. The properties of U{sub 3}Si{sub 2}, such as stable crystalline structures, density of states, charge distributions, formation energy of defects, as well as the mechanical properties are explored. The calculation results show that the U{sub 3}Si{sub 2} material is metallic and brittle, which is in good agreement with the previous experimental observations. The formation energy of uranium vacancy defect is predicted to be the lowest, similar with that of UN. The theoretical investigation of this work is expected to provide new insight of uranium silicide fuels.

  1. Teaching Photosynthesis in a Compulsory School Context. Students’ Reasoning, Understanding and Interactions.

    Directory of Open Access Journals (Sweden)

    Helena Näs

    2011-02-01

    Full Text Available According to previous research, students show difficulties in understanding photosynthesis and respiration, and basic ecological concepts like energy flow in ecosystems. There are successful teaching units accomplished in this area and many of them can be described as inquiry-based teaching. One definition of inquiry-based teaching is that it involves everything from finding problems, investigating them, debating with peers and trying to explain and give solutions. Accordingly students need to be confronted with challenging questions and empirical data to reason about and teachers need to implement student-generated inquiry discussion since students often stay silent and do not express their thoughts during science lessons. This thesis will focus on young peoples’ understanding of the functioning of plants, students’ participation during biology lessons, and how biology teaching is accomplished in primary and secondary school.Two school classroom projects focusing on teaching about plants and ecology are described. Four teachers and their 4th, 5th and 6th grade classes plus two science teachers and their three 8th grade classes collaborated. Photosynthesis and respiration were made concrete by using tasks where plants, plant cells, germs, seeds and the gas exchange were used. The aim was to listen to students’ reasoning in both teaching and interview situations. Learning outcome, as described by students’ reasoning in the classrooms and in individual interviews but also by their test results, is especially focused. Student-student and student-teacher interactions have been analysed with an ethnographic approach in the classroom context.The plant tasks encouraged the students’ in primary school to develop scientific reasoning and the interviews confirmed that the students had learned about photosynthesis. The ecology teaching in secondary school showed a substantial understanding confirmed both by students’ oral and written

  2. Aging phenomena in Cu{sub 0.1}Ni{sub 0.8}Co{sub 0.2}Mn{sub 1.9}O{sub 4} NTC ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Shpotyuk, O.; Vakiv, M.; Mrooz, O. [Scientific Research Co. ' ' Carat' ' , Lviv (Ukraine); Hadzaman, I. [Scientific Research Co. ' ' Carat' ' , Lviv (Ukraine); Drohobych State Pedagogical Univ., Drohobych (Ukraine); Plewa, J.; Uphoff, H.; Altenburg, H. [Fachhochschule Muenster, Steinfurt (Germany)

    2002-07-01

    Aging effects in Cu{sub 0.1}Ni{sub 0.8}Co{sub 0.2}Mn{sub 1.9}O{sub 4} NTC ceramics were studied for the first time by electrical and microstructural measurements. The increase in resistivity induced by aging tests at 125 and 170 C during 1000 h was observed. The changes of the electrical properties of the investigated NTC thermistors were explained, using the results of ceramics microstructural characterization, thermogravimetry, optical and electron microscopy techniques. (orig.)

  3. Hydrogen storage and microstructure investigations of La{sub 0.7-x}Mg{sub 0.3}Pr{sub x}Al{sub 0.3}Mn{sub 0.4}Co{sub 0.5}Ni{sub 3.8} alloys

    Energy Technology Data Exchange (ETDEWEB)

    Galdino, G.S.; Casini, J.C.S.; Ferreira, E.A.; Faria, R.N.; Takiishi, H., E-mail: agsgaldino@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (DM/IPEN-CNEN/SP), Sao Paulo, SP (Brazil). Dept. de Metalurgia

    2010-07-01

    The effects of substitution of Pr for La in the hydrogen storage capacity and microstructures of La{sub 0.7-x}Pr{sub x}Mg{sub 0.3}Al{sub 0.3}Mn{sub 0.4}Co{sub 0.5}Ni{sub 3.8} (x=0, 0.1, 0.3, 0.5, 0.7) alloys electrodes have been studied. X-ray diffraction (XRD), scanning electron microscopy, energy dispersive spectrometry (EDS) and electrical tests were carried out in a the alloys and electrodes. Cycles of charge and discharge have also been carried out in the Ni/MH (Metal hydride) batteries based on the alloys negative electrodes. (author)

  4. The Comparison of the Inquiry Behavior of ISCS and Non-ISCS Science Students as Measured by the Tab Science Test

    Science.gov (United States)

    Stallings, Everett S.; Snyder, William R.

    1977-01-01

    Studies of a group of seventh-grade students who were tested for inquiry skills using the TAB Science Test showed no significant differences between those students who had studied the Intermediate Science Curriculum Study (ISCS) and those who studied another curriculum. (MLH)

  5. Validity of a new assessment rubric for a short-answer test of clinical reasoning.

    Science.gov (United States)

    Yeung, Euson; Kulasagarem, Kulamakan; Woods, Nicole; Dubrowski, Adam; Hodges, Brian; Carnahan, Heather

    2016-07-26

    The validity of high-stakes decisions derived from assessment results is of primary concern to candidates and certifying institutions in the health professions. In the field of orthopaedic manual physical therapy (OMPT), there is a dearth of documented validity evidence to support the certification process particularly for short-answer tests. To address this need, we examined the internal structure of the Case History Assessment Tool (CHAT); this is a new assessment rubric developed to appraise written responses to a short-answer test of clinical reasoning in post-graduate OMPT certification in Canada. Fourteen physical therapy students (novices) and 16 physical therapists (PT) with minimal and substantial OMPT training respectively completed a mock examination. Four pairs of examiners (n = 8) participated in appraising written responses using the CHAT. We conducted separate generalizability studies (G studies) for all participants and also by level of OMPT training. Internal consistency was calculated for test questions with more than 2 assessment items. Decision studies were also conducted to determine optimal application of the CHAT for OMPT certification. The overall reliability of CHAT scores was found to be moderate; however, reliability estimates for the novice group suggest that the scale was incapable of accommodating for scores of novices. Internal consistency estimates indicate item redundancies for several test questions which will require further investigation. Future validity studies should consider discriminating the clinical reasoning competence of OMPT trainees strictly at the post-graduate level. Although rater variance was low, the large variance attributed to error sources not incorporated in our G studies warrant further investigations into other threats to validity. Future examination of examiner stringency is also warranted.

  6. Big Bang nucleosynthesis: Accelerator tests and can Ω/sub B/ really be large

    International Nuclear Information System (INIS)

    Schramm, D.N.

    1987-10-01

    The first collider tests of cosmological theory are now underway. The number of neutrino families in nature, N/sub nu/, plays a key role in elementary particle physics as well as in the synthesis of the light elements during the early evolution of the Universe. Standard Big Bang Nucleosynthesis argues for N/sub nu/ = 3 +- 1. Current limits on N/sub nu/ from the CERN anti pp collider and e + e - colliders are presented and compared to the cosmological bound. Supernova SN 1987A is also shown to give a limit on N/sub nu/ comparable to current accelerator bounds. All numbers are found to be small thus verifying the Big Bang model at an earlier epoch than is possible by traditional astronomical observations. Future measurements at SLC and LEP will further tighten this argument. Another key prediction of the standard Big Bang Nucleosynthesis is that the baryon density must be small (Ω/sub B/ ≤ 0.1). Recent attempts to try to subvert this argument using homogeneities of various types are shown to run afoul of the 7 Li abundance which has now become a rather firm constraint. 18 refs., 2 figs

  7. Reasoning=working Memoryattention

    Science.gov (United States)

    Buehner, M.; Krumm, S.; Pick, M.

    2005-01-01

    The purpose of this study was to clarify the relationship between attention, components of working memory, and reasoning. Therefore, twenty working memory tests, two attention tests, and nine intelligence subtests were administered to 135 students. Using structural equation modeling, we were able to replicate a functional model of working memory…

  8. Normal Science in a Multiverse

    Science.gov (United States)

    Carroll, Sean

    2016-06-01

    A number of theories in contemporary physics and cosmology place an emphasis on features that are hard, and arguably impossible, to test. These include the cosmological multiverse as well as some approaches to quantum gravity. Worries have been raised that these models attempt to sidestep the purportedly crucial principle of falsifiability. Proponents of these theories sometimes suggest that we are seeing a new approach to science, while opponents fear that we are abandoning science altogether. I will argue that in fact these theories are straightforwardly scientific and can be evaluated in absolutely conventional ways, based on empiricism, abduction (inference to the best explanation), and Bayesian reasoning. The integrity of science remains intact.

  9. Science Literacy: How do High School Students Solve PISA Test Items?

    Science.gov (United States)

    Wati, F.; Sinaga, P.; Priyandoko, D.

    2017-09-01

    The Programme for International Students Assessment (PISA) does assess students’ science literacy in a real-life contexts and wide variety of situation. Therefore, the results do not provide adequate information for the teacher to excavate students’ science literacy because the range of materials taught at schools depends on the curriculum used. This study aims to investigate the way how junior high school students in Indonesia solve PISA test items. Data was collected by using PISA test items in greenhouse unit employed to 36 students of 9th grade. Students’ answer was analyzed qualitatively for each item based on competence tested in the problem. The way how students answer the problem exhibits their ability in particular competence which is influenced by a number of factors. Those are students’ unfamiliarity with test construction, low performance on reading, low in connecting available information and question, and limitation on expressing their ideas effectively and easy-read. As the effort, selected PISA test items can be used in accordance teaching topic taught to familiarize students with science literacy.

  10. Relational Reasoning in STEM Domains: A Foundation for Academic Development

    Science.gov (United States)

    Alexander, Patricia A.

    2017-01-01

    What is relational reasoning? Why is it critical to consider the role of relational reasoning in students learning and development in science, technology, engineering, and mathematics (STEM)? Moreover, how do the particular contributions populating this special issue address the pressing societal needs and offer guidance to researchers and…

  11. Preparation and photocatalytic activity of ZnO/Fe{sub 2}O{sub 3} nanotube composites

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yanjun; Sun, Li; Wu, Jiagen; Fang, Ting; Cai, Ran; Wei, Ang, E-mail: wei1177@126.com

    2015-04-15

    Highlights: • ZnO/Fe{sub 2}O{sub 3} tubular structure was prepared via photochemical deposition at RT. • The composites show a great improvement in photocatalytic characteristics. • The possible reasons of photocatalytic performance of composites were researched. • The formation mechanism of ZnO/Fe{sub 2}O{sub 3} tubular structure was discussed. - Abstract: Fe{sub 2}O{sub 3} nanoparticles were grown on ZnO nanorods (NRs) to form ZnO/Fe{sub 2}O{sub 3} nanotube (NT) composites via photochemical deposition under ultraviolet light irradiation at a room temperature. Fe{sup 3+} ions in the solution preferentially adhere to the metastable Zn-rich (0 0 0 1) polar surfaces in ZnO NRs, which leading to the formation of ZnO/Fe{sub 2}O{sub 3} NTs. ZnO/Fe{sub 2}O{sub 3} NT nanocomposites show a great improvement in photocatalytic characteristics compared with the bare ZnO NRs. It can be inferred that the enhanced photocatalytic performance of ZnO/Fe{sub 2}O{sub 3} is benefit from the synergistic effect of ZnO and Fe{sub 2}O{sub 3} semiconductors.

  12. "Why should I have come here?"--A qualitative investigation of migration reasons and experiences of health workers from sub-Saharan Africa in Austria.

    Science.gov (United States)

    Jirovsky, Elena; Hoffmann, Kathryn; Maier, Manfred; Kutalek, Ruth

    2015-02-26

    There are many health professionals from abroad working in the European Union and in Austria. The situation of sub-Saharan health workers in particular has now been studied for the first time. The objective was to explore their reasons for migration to Austria, as well as their personal experiences concerning the living and working situation in Austria. We conducted semi-structured, qualitative interviews with African health workers. They were approached via professional networks and a snowball system. The interviews were transcribed and analysed using atlas.ti. For most of our participants, the decision to migrate was not professional but situation dependent. Austria was not their first choice as a destination country. Several study participants left their countries to improve their overall working situation. The main motivation for migrating to Austria was partnership with an Austrian citizen. Other immigrants were refugees. Most of the immigrants found the accreditation process to work as a health professional to be difficult and hindering. This resulted in some participants not being able to work in their profession, while others were successful in their profession or in related fields. There have been experiences of discrimination, but also positive support. Austria is not an explicit target country for health workers from sub-Saharan Africa. Most of the study participants experienced bad work and study conditions in their home countries, but they are in Austria mostly because of personal connections. The competencies of those who are here are not fully utilised. The major reason is Austria's current resident and work permit regulations concerning African citizens. In addition, the accreditation process and the German language appear to be barriers.

  13. Reasoning by analogy: rational foundation of natural analogue studies

    International Nuclear Information System (INIS)

    Petit, J.-C.

    1992-01-01

    Long-term extrapolations concerning the safety of a nuclear waste repository cannot be satisfactorily made on the sole basis of short-term laboratory investigations. Most nuclear countries have hence developed an approach relying on the following research directions: 1. laboratory experiments; 2. in situ testing; 3. modeling; and 4. natural analogues, which are the only means by which very slow mechanisms can be identified and by which long-term predictions of models can be tested for pertinence (if not truly validated). Although the field of natural analogues has grown very rapidly in recent years, receiving support from varied specialists and institutions involved in radioactive waste disposal, there is not yet a full consensus on their actual usefulness. More problematic is the criticism sometimes made that analogical reasoning is not ''true science'' and that information retrieved from the study of natural analogues will always remain questionable. The present paper gives some clues about the exact status of reasoning by analogy, compared to more ''scientific'' ways of deriving information from investigated systems. It is not a thorough discussion of this very complex, and by far too philosophical issue but we hope, at least, to present to readers of papers devoted to natural analogue studies arguments showing that this approach has some sound foundation. (author)

  14. Elementary Science Indoors and Out: Teachers, Time, and Testing

    Science.gov (United States)

    Carrier, Sarah J.; Tugurian, Linda P.; Thomson, Margareta M.

    2013-10-01

    In this article, we present the results from a mixed-methods research study aimed to document indoor and outdoor fifth grade science experiences in one school in the USA in the context of accountability and standardized testing. We used quantitative measures to explore students' science knowledge, environmental attitudes, and outdoor comfort levels, and via qualitative measures, we examined views on science education and environmental issues from multiple sources, including the school's principal, teachers, and students. Students' science knowledge in each of the four objectives specified for grade 5 significantly improved during the school year. Qualitative data collected through interviews and observations found limited impressions of outdoor science. Findings revealed that, despite best intentions and a school culture that supported outdoor learning, it was very difficult in practice for teachers to supplement their classroom science instruction with outdoor activities. They felt constrained by time and heavy content demands and decided that the most efficient way of delivering science instruction was through traditional methods. Researchers discuss potentials and obstacles for the science community to consider in supporting teachers and preparing elementary school teachers to provide students with authentic experiential learning opportunities. We further confront teachers' and students' perceptions that science is always best and most efficiently learned inside the classroom through traditional text-driven instruction.

  15. Heuristics Reasoning in Diagnostic Judgment.

    Science.gov (United States)

    O'Neill, Eileen S.

    1995-01-01

    Describes three heuristics--short-cut mental strategies that streamline information--relevant to diagnostic reasoning: accessibility, similarity, and anchoring and adjustment. Analyzes factors thought to influence heuristic reasoning and presents interventions to be tested for nursing practice and education. (JOW)

  16. Management of Holding and Evaluating Comprehensive System of Electronic Clinical Reasoning Exams (Sajab in the Sixth Nationwide Medical Sciences Students Olympiad

    Directory of Open Access Journals (Sweden)

    Manouchehr Khoshbaten

    2015-12-01

    Full Text Available Introduction: The Nationwide Medical Sciences Students purpose of the Olympiad is to discover student’s talents and encourage them to study. It seems that holding regional Olympiad exams to select students for the National Olympiad can help us to maintain fairness. The aim of this study is Management of Holding and Evaluating Clinical Reasoning Exams Using a Comprehensive System of Electronic Clinical Reasoning Exams. Methods: Study was carried out in 2013 at the University of Medical Sciences on 750 students, 250 question designers, 37 responsibles. The nationwide universities held regional exams for the Student Olympiad in the area of clinical reasoning on specific dates and times. A quality review of the exams was done to study the strengths and weaknesses and to eliminate shortcomings and problems. Therefore, a researcher created a questionnaire with a reliability of R= 0.86 and validity was confirmed by experts, which was then loaded into the system. The collected data were analyzed using SPSS and descriptive statistics (Percent, Average, standard deviation. Results: The multimedia educational quality of the system, with an average of 69.36 ±22.79, the students and faculty members evaluated as good, with averages of 64.30 ±23.48 and 67.28 ± 22.43, respectively. The quality of the exam was evaluated as excellent by faculty members, with an average of 94.63 ±16.60 and 59.52 ±27.46, by the students. Conclusion: Evaluating the quality of the system’s performance and its ability to assess students will lead to a clarification of its strengths and weaknesses. Finally, result in the creation of a high quality evaluation system.

  17. Sintering behaviour and phase relationships of Si[sub 3]N[sub 4] ceramics in the Si[sub 3]N[sub 4]-SiO[sub 2]-MgO-Y[sub 2]O[sub 3] system. Sinterverhalten und Phasenbeziehungen von Si[sub 3]N[sub 4]-Keramiken im System Si[sub 3]N[sub 4]-SiO[sub 2]-MgO-Y[sub 2]O[sub 3

    Energy Technology Data Exchange (ETDEWEB)

    Mahoney, F.M.

    1992-10-12

    The aim of this work is the investigation of the sintering or crystallisation behaviour of Si[sub 3]N[sub 4] ceramics depending on the additive composition in the Si[sub 3]N[sub 4]-SiO[sub 2]-MgO-Y[sub 2]O[sub 3] system. With regard to the complicated manufacturing process of sintered and heat-treated Si[sub 3]N[sub 4] ceramics, one should first determine which additive compositions make complete compression possible. The effect of the composition on the volume and the viscosity of the melting phase should be cleared up, where determining the Si[sub 3]N[sub 4] solubility relative to the additive composition is of special importance. The phase relationships between Si[sub 3]N[sub 4] and the possible crystalline secondary phases should be determined for the crystallisation behaviour. Due to the very fine distribution of only a 5-15% proportion of additive in conventional Si[sub 3]N[sub 4] samples, a characterisation of the secondary phases is difficult to carry out with X-ray or REM/EDX analysis. Therefore, experiments with oxy-nitridic model samples were carried out in this work, which have the same phase relationships as conventional Si[sub 3]N[sub 4] compositions, but with an appreciably higher proportion of additive. The possibility of transferring the results of the model samples were tested on examples of three Si[sub 3]N[sub 4] ceramics. (orig.)

  18. High school Physical Sciences teachers' competence in some basic cognitive skills

    OpenAIRE

    Selvaratnam, Mailoo

    2011-01-01

    The successful implementation of the national high school Physical Sciences curriculum in South Africa, which places strong emphasis on critical thinking and reasoning abilities of students, would need teachers who are competent in cognitive skills and strategies. The main objectives of this study were to test South African high school Physical Sciences teachers' competence in the cognitive skills and strategies needed for studying Physical Sciences effectively and also to identify possible r...

  19. Comparing the luminescence processes of YVO{sub 4}:Eu and core-shell YVO{sub 4}@YF{sub 3} nanocrystals with bulk-YVO{sub 4}:Eu

    Energy Technology Data Exchange (ETDEWEB)

    Shirmane, L., E-mail: liana.shirmane@gmail.com [Institute of Solid State Physics, University of Latvia, 8 Kengaraga iela, LV-1063 Riga (Latvia); Feldmann, C. [Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstrasse 15, D-76131 Karlsruhe (Germany); Pankratov, V., E-mail: vladimirs.pankratovs@oulu.fi [Institute of Solid State Physics, University of Latvia, 8 Kengaraga iela, LV-1063 Riga (Latvia); MAX IV Laboratory, Box 118, S-221 00 Lund (Sweden); Research Center of Molecular Materials, University of Oulu, P.O. Box 3000, FIN-90014 Oulu (Finland)

    2017-01-01

    Comparative analysis of bulk, non-coated and core-shelled nanocrystalline YVO{sub 4}:Eu was performed by means of time-resolved luminescence and VUV excitation luminescence spectroscopy techniques. Nanocrystalline YVO{sub 4}:Eu samples – both as-prepared and YF{sub 3} core-shelled – have been synthesized by means of a microwave-assisted synthesis in ionic liquids, which allows to obtain 10–12 nm nanoparticles with high crystallinity. The results show noticeable differences between bulk and nanocrystalline YVO{sub 4}:Eu in photoluminescence experimental data, which explains by influence of the nanocrystal surface. A YF{sub 3} core-shell layer around YVO{sub 4}:Eu nanoparticles partially recovers the intensity of the Eu{sup 3+} emission. It is demonstrated that the Eu{sup 3+} luminescence recovery is achieved at the expense of the suppression of the intrinsic emission but not due to the passivation of surface loss centers in core-shelled nanocrystals. It is also shown that surface loss processes are the reason of the degradation of energy transfer efficiency from the host lattice to Eu{sup 3+} under high-energy excitations in vacuum ultraviolet spectral range.

  20. Glass formation ability, structure and magnetocaloric effect of a heavy rare-earth bulk metallic glassy Gd{sub 55}Co{sub 20}Fe{sub 5}Al{sub 20} alloy

    Energy Technology Data Exchange (ETDEWEB)

    Jo, C.-L. [Shanghai University, School of Materials Science and Engineering, Yanchang Road 149, Zhabei District, 200072 Shanghai (China)], E-mail: jochollong@163.com; Xia Lei; Ding Ding; Dong Yuanda; Gracien, Ekoko [Shanghai University, School of Materials Science and Engineering, Yanchang Road 149, Zhabei District, 200072 Shanghai (China)

    2008-06-30

    The glass formation ability, the structure and the magnetocaloric effect of the bulk metallic glassy Gd{sub 55}Co{sub 20}Fe{sub 5}Al{sub 20} alloy were investigated. Bulk metallic glassy (BMGs) alloys were prepared by a copper-mold casting method. The glass forming ability and their structure were studied by using X-ray diffraction (XRD) and differential scanning calorimeter (DSC). The XRD analysis revealed that the as-cast cylinder of Gd{sub 55}Co{sub 20}Fe{sub 5}Al{sub 20} alloy showed fully amorphous structure in 2 mm diameter. The DSC revealed that the bulk cylinder of the Gd{sub 55}Co{sub 20}Fe{sub 5}Al{sub 20} alloy showed a distinct glass transition temperature and a relatively wide supercooled liquid region before crystallization. SQUID investigated the magnetic properties and the entropy changes. The Curie temperature of Gd{sub 55}Co{sub 20}Fe{sub 5}Al{sub 20} BMGs alloy was about 130 K, but the maximum magnetic entropy changes(-{delta}S{sub M}) showed at about 125 K, a little lower than the Curie temperature 130 K. The reason could probably be due to the presence of a little amount of nanocrystalline particles between amorphous phases. The BMG alloy has the characteristic of second-order transition (SOT) on Arrott plots. The results showed that the amorphous sample had a relatively improved magnetocaloric effect, indicating that the amorphous alloy could be considered as a candidate for magnetic refrigeration applications in the temperature interval range of 100-200 K.

  1. Simplified Predictive Models for CO<sub>2sub> Sequestration Performance Assessment: Research Topical Report on Task #4 - Reduced-Order Method (ROM) Based Models

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Srikanta; Jin, Larry; He, Jincong; Durlofsky, Louis

    2015-06-30

    Reduced-order models provide a means for greatly accelerating the detailed simulations that will be required to manage CO<sub>2sub> storage operations. In this work, we investigate the use of one such method, POD-TPWL, which has previously been shown to be effective in oil reservoir simulation problems. This method combines trajectory piecewise linearization (TPWL), in which the solution to a new (test) problem is represented through a linearization around the solution to a previously-simulated (training) problem, with proper orthogonal decomposition (POD), which enables solution states to be expressed in terms of a relatively small number of parameters. We describe the application of POD-TPWL for CO<sub>2sub>-water systems simulated using a compositional procedure. Stanford’s Automatic Differentiation-based General Purpose Research Simulator (AD-GPRS) performs the full-order training simulations and provides the output (derivative matrices and system states) required by the POD-TPWL method. A new POD-TPWL capability introduced in this work is the use of horizontal injection wells that operate under rate (rather than bottom-hole pressure) control. Simulation results are presented for CO<sub>2sub> injection into a synthetic aquifer and into a simplified model of the Mount Simon formation. Test cases involve the use of time-varying well controls that differ from those used in training runs. Results of reasonable accuracy are consistently achieved for relevant well quantities. Runtime speedups of around a factor of 370 relative to full- order AD-GPRS simulations are achieved, though the preprocessing needed for POD-TPWL model construction corresponds to the computational requirements for about 2.3 full-order simulation runs. A preliminary treatment for POD-TPWL modeling in which test cases differ from training runs in terms of geological parameters (rather than well controls) is also presented. Results in this case involve only small differences between

  2. Where The Wild Seafloor Scientists Are: Using Interactive Picture Books To Educate Children About Sub-seafloor Science

    Science.gov (United States)

    Kurtz, K.

    2015-12-01

    Sub-seafloor scientific research has the power to spark the imaginations of elementary age children with its mysterious nature, cutting-edge research, and its connections to kid friendly science topics, such as volcanoes, the extinction of dinosaurs and the search for extraterrestrial life. These factors have been utilized to create two interactive eBooks for elementary students and teachers, integrating high quality science information, highly engaging and age-appropriate illustrations, and rhyming text. One book introduces children to the research and discoveries of the JOIDES Resolution research vessel. The second focuses on the discoveries of microbial life in the sub-seafloor. The eBooks present information as traditional, linear, illustrated children's books, but the eBook format allows the book to be available online for free to anyone and allows teachers to project the book on a classroom screen so all students can easily see the illustrations. The iPad versions also provide an interactive, learner-led educational experience, where cognitively appropriate videos, photos and other forms of information can be accessed with the tap of a finger to answer reader questions and enrich their learning experience. These projects provide an example and model of the products that can result from high level and meaningful partnerships between scientists, educators, artists and writers.

  3. The legal reasoning skills. Theoretical considerations

    Directory of Open Access Journals (Sweden)

    Lisett D. Páez Cuba

    2014-06-01

    Full Text Available This research analyzes the legal reasoning as essential skills to the teaching - learning process of law. This approach is based on a theoretical systematization of the Theory of Legal Argumentation (TLA that allows the conception of law as an argumentative act itself. It also determines, as a new element, the inclusion of legal argumentation as the final phase of the law cycle, which has particular impact on the teaching of this science. In this regard, the proposal of three skills of legal reasoning is made: interpreting the law, enforce the rule of law and legally argue the legal decision.

  4. Controlled synthesis and photoluminescence properties of In{sub 2}O{sub 3} rods with dodecahedron In{sub 2}O{sub 3} microcrystals on top

    Energy Technology Data Exchange (ETDEWEB)

    Ouacha, Hassan [King Abdullah Institute for Nanotechnology, King Saud University, Riyadh (Saudi Arabia); Hendaoui, Ali [Department of Physics, College of Science and General Studies, Alfaisal University, Riyadh (Saudi Arabia); Kleineberg, Ulf [Faculty of Physics, Ludwig Maximilian University of Munich, Garching (Germany); Albrithen, Hamad; Azzeer, Abdallah [Physics and Astronomy Department, King Saud University, Riyadh (Saudi Arabia)

    2017-10-15

    In{sub 2}O{sub 3} rods with dodecahedron In{sub 2}O{sub 3} microcrystals on top were synthesized in an electrical furnace via Au-catalyzed vapor transport process. A catalyst-assisted selective vapor-solid (VS) growth was proposed to explain the formation of the dodecahedron In{sub 2}O{sub 3} microcrystal, while the self-catalytic VS growth mechanism dominated the subsequent one-dimensional (1D) growth of the In{sub 2}O{sub 3} rod underneath the In{sub 2}O{sub 3} microcrystal. The structural evolution of these structures was carefully examined during the synthesis process by controlling the growth parameters. The morphologies, crystalline structures and surface chemistry were characterized by scanning electron microscopy (SEM), X-ray diffraction technique (XRD), and X-ray photoelectron spectroscopy (XPS), respectively. The photoluminescence (PL) spectrum at room temperature of the as-grown In{sub 2}O{sub 3} structures exhibited both UV and blue luminescence emission under one excitation at 260 nm, which may be related to the existence of oxygen vacancies. The synthesized multifaceted In{sub 2}O{sub 3} microcrystal has shown to contain a large number of vertices and may find many applications in developing three-dimensional (3D) resonators. This work will not only enrich the synthesis science but also will open doors for applications of such structures in optical devices. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Computer-Based Assessment of School Readiness and Early Reasoning

    Science.gov (United States)

    Csapó, Beno; Molnár, Gyöngyvér; Nagy, József

    2014-01-01

    This study explores the potential of using online tests for the assessment of school readiness and for monitoring early reasoning. Four tests of a face-to-face-administered school readiness test battery (speech sound discrimination, relational reasoning, counting and basic numeracy, and deductive reasoning) and a paper-and-pencil inductive…

  6. A concept analysis of abductive reasoning.

    Science.gov (United States)

    Mirza, Noeman A; Akhtar-Danesh, Noori; Noesgaard, Charlotte; Martin, Lynn; Staples, Eric

    2014-09-01

    To describe an analysis of the concept of abductive reasoning. In the discipline of nursing, abductive reasoning has received only philosophical attention and remains a vague concept. In addition to deductive and inductive reasoning, abductive reasoning is not recognized even in prominent nursing knowledge development literature. Therefore, what abductive reasoning is and how it can inform nursing practice and education was explored. Concept analysis. Combinations of specific keywords were searched in Web of Science, CINAHL, PsychINFO, PubMed, Medline and EMBASE. The analysis was conducted in June 2012 and only literature before this period was included. No time limits were set. Rodger's evolutionary method for conducting concept analysis was used. Twelve records were included in the analysis. The most common surrogate term was retroduction, whereas related terms included intuition and pattern and similarity recognition. Antecedents consisted of a complex, puzzling situation and a clinician with creativity, experience and knowledge. Consequences included the formation of broad hypotheses that enhance understanding of care situations. Overall, abductive reasoning was described as the process of hypothesis or theory generation and evaluation. It was also viewed as inference to the best explanation. As a new approach, abductive reasoning could enhance reasoning abilities of novice clinicians. It can not only incorporate various ways of knowing but also its holistic approach to learning appears to be promising in problem-based learning. As nursing literature on abductive reasoning is predominantly philosophical, practical consequences of abductive reasoning warrant further research. © 2014 John Wiley & Sons Ltd.

  7. Influence of ''inert'' diluent gases on the rate of carbon gasification. [Effect of N/sub 2/, Ar, or He diluent on reaction with O/sub 2/ or CO/sub 2/

    Energy Technology Data Exchange (ETDEWEB)

    Walker, P.L. Jr.; Pentz, L.; Biederman, D.L.; Vastola, F.J.

    1977-01-01

    The effect of diluent gases on gasification rates of the C--O/sub 2/ and C--CO/sub 2/ reactions has been studied. At equal starting pressures of reactant and diluent, rates for both reactions are: N/sub 2/ > Ar > He. For the C--CO/sub 2/ reaction, the presence of a diluent results in higher gasification rates than when no diluent is present in the order: Xe > N/sub 2/ > Ar. Possible reasons for the diluent effects are discussed.

  8. Prueba de Ciencia Primer Grado (Science Test for the First Grade). [In Spanish

    Science.gov (United States)

    Puerto Rico State Dept. of Education, Hato Rey.

    This document consists of three parts: (1) a manual for administering the science test to first graders (in Spanish), (2) a copy of the test itself (pictorial), and (3) a list of expected competencies in science for the first three grades (in English). The test consists of 25, four-choice items. For each item, the administrator reads a statement…

  9. Reasoning with alternative explanations in physics: The cognitive accessibility rule

    Science.gov (United States)

    Heckler, Andrew F.; Bogdan, Abigail M.

    2018-06-01

    A critical component of scientific reasoning is the consideration of alternative explanations. Recognizing that decades of cognitive psychology research have demonstrated that relative cognitive accessibility, or "what comes to mind," strongly affects how people reason in a given context, we articulate a simple "cognitive accessibility rule", namely that alternative explanations are considered less frequently when an explanation with relatively high accessibility is offered first. In a series of four experiments, we test the cognitive accessibility rule in the context of consideration of alternative explanations for six physical scenarios commonly found in introductory physics curricula. First, we administer free recall and recognition tasks to operationally establish and distinguish between the relative accessibility and availability of common explanations for the physical scenarios. Then, we offer either high or low accessibility explanations for the physical scenarios and determine the extent to which students consider alternatives to the given explanations. We find two main results consistent across algebra- and calculus-based university level introductory physics students for multiple answer formats. First, we find evidence that, at least for some contexts, most explanatory factors are cognitively available to students but not cognitively accessible. Second, we empirically verify the cognitive accessibility rule and demonstrate that the rule is strongly predictive, accounting for up to 70% of the variance of the average student consideration of alternative explanations across scenarios. Overall, we find that cognitive accessibility can help to explain biases in the consideration of alternatives in reasoning about simple physical scenarios, and these findings lend support to the growing number of science education studies demonstrating that tasks relevant to science education curricula often involve rapid, automatic, and potentially predictable processes and

  10. Competence of matric physical science teachers in some basic problem-solving strategies

    Directory of Open Access Journals (Sweden)

    Mailoo Selvaratnam

    2011-01-01

    Full Text Available The National Curriculum Statement for matric physical science places strong emphasis on the development of critical thinking and reasoning abilities of pupils. The successful implementation of this curriculum therefore requires teachers who are competent in the cognitive (intellectual skills and strategies needed for learning science effectively. Testing of teachers’ competence in this aspect is therefore important. I therefore analysed teachers’ answers to questions that were carefully designed to test competence in some basic intellectual strategies that are important for problem solving in physical science courses. A total of 73 matric physical science teachers, from about 50 Dinaledi schools in the North West and KwaZulu-Natal provinces in South Africa, were tested in five intellectual strategies: clear representation of problems, identifying and focusing on the goal, identification and use of relevant principles, use of equations for deductions and proceeding step-by-step with the solution. The teachers’ competence was poor in all the intellectual strategies tested. About 60% (the average performance in all 13 questions used for testing of teachers tested were unable to solve the questions correctly. An important objective of the curriculum is the development of critical thinking, scientific reasoning and strategies of pupils. This study shows that the achievement of this objective will be seriously handicapped because of the lack of competence of many teachers in intellectual strategies. There is therefore a need to train teachers in order to increase their competence in this aspect.

  11. Engineering of mixed pairing and non-Abelian Majorana states in chiral p-wave superconductor Sr<sub>2sub>RuO>4sub> and other materials

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ying [Pennsylvania State Univ., University Park, PA (United States). Dept. of Physics

    2015-11-30

    This project deals with odd-parity superconductor Sr<sub>2sub>RuO>4sub> and related material systems, aiming at understanding the unconventional nature of superconductivity in this material. An odd-parity superconductor is expected to feature a novel topological object, the half-flux-quantum vortex that hosts a Majorana anyons. Majorana anyons carry non-Abelian statistics that can be used as the building block for constructing a fault-tolerated topological quantum computer. Half-flux-quantum vortices form in an odd-parity superconductor because of the availability of charge neutral spin supercurrent in addition to the normal supercurrent. Half-height magnetization steps were found in a cantilever magnetometry measurement of doubly connected mesoscopic samples of Sr<sub>2sub>RuO>4sub> in the presence of an in-plane magnetic field (J. Jang, D. G. Ferguson, V. Vakaryuk, R. Budakian, S. B. Chung, P. M. Goldbart, and Y. Maeno, Science 331, 186 (2011)), which suggests the presence of a half-flux-quantum (Φ<sub>0sub>/2 = h/4e) state. Evidence for half flux quantum states, which can be viewed as coreless half vortices, was obtained in mesoscopic samples of Sr<sub>2sub>RuO>4sub> in the torque magnetomitry measurements. However, the existence of such an important property has not been confirmed by any other independent measurement.

  12. Reasoning and change management in modular ontologies

    NARCIS (Netherlands)

    Stuckenschmidt, Heiner; Klein, Michel

    2007-01-01

    The benefits of modular representations are well known from many areas of computer science. While in software engineering modularization is mainly a vehicle for supporting distributed development and re-use, in knowledge representation, the main goal of modularization is efficiency of reasoning. In

  13. Implementation science: a role for parallel dual processing models of reasoning?

    Science.gov (United States)

    Sladek, Ruth M; Phillips, Paddy A; Bond, Malcolm J

    2006-05-25

    A better theoretical base for understanding professional behaviour change is needed to support evidence-based changes in medical practice. Traditionally strategies to encourage changes in clinical practices have been guided empirically, without explicit consideration of underlying theoretical rationales for such strategies. This paper considers a theoretical framework for reasoning from within psychology for identifying individual differences in cognitive processing between doctors that could moderate the decision to incorporate new evidence into their clinical decision-making. Parallel dual processing models of reasoning posit two cognitive modes of information processing that are in constant operation as humans reason. One mode has been described as experiential, fast and heuristic; the other as rational, conscious and rule based. Within such models, the uptake of new research evidence can be represented by the latter mode; it is reflective, explicit and intentional. On the other hand, well practiced clinical judgments can be positioned in the experiential mode, being automatic, reflexive and swift. Research suggests that individual differences between people in both cognitive capacity (e.g., intelligence) and cognitive processing (e.g., thinking styles) influence how both reasoning modes interact. This being so, it is proposed that these same differences between doctors may moderate the uptake of new research evidence. Such dispositional characteristics have largely been ignored in research investigating effective strategies in implementing research evidence. Whilst medical decision-making occurs in a complex social environment with multiple influences and decision makers, it remains true that an individual doctor's judgment still retains a key position in terms of diagnostic and treatment decisions for individual patients. This paper argues therefore, that individual differences between doctors in terms of reasoning are important considerations in any

  14. Structural study of (N{sub 2}H{sub 5},H){sub 2.9}U{sub 1.1}Ce{sub 0.9}(C{sub 2}O{sub 4}){sub 5}·10H{sub 2}O from a conventional X-ray diffraction diagram obtained on a powder synthesized by a fast vortex process

    Energy Technology Data Exchange (ETDEWEB)

    Brackx, E., E-mail: Emmanuelle.brackx@cea.fr [CEA, DEN, DTEC, SGCS, LMAC, Marcoule, 30207 Bagnols sur Cèze (France); Laval, J.P. [Centre Européen de la Céramique, SPCTS, UMR-CNRS 7315, Université de Limoges, Faculté des Sciences, 12 rue Atlantis, 87068 Limoges (France); Dugne, O. [CEA, DEN, DTEC, SGCS, LMAC, Marcoule, 30207 Bagnols sur Cèze (France); Feraud, J.P. [CEA, DEN, DTEC, SGCS, LGCI, Marcoule, 30207 Bagnols sur Cèze (France); Arab-Chapelet, B. [CEA, DEN, DRCP, SCPS, LC2A, Marcoule, 30207 Bagnols sur Cèze (France)

    2015-01-15

    In the context of research on U/minor actinides for nuclear fuel reprocessing in the transmutation process, developments are first studied with surrogates containing uranium and lanthanides to facilitate testing. The tests consist of precipitating and calcining a hydrazinium uranium/cerium oxalate. The structure of this oxalate had not been previously determined, but was necessary to validate the physicochemical mechanisms involved. The present study, firstly demonstrates the structural similarity of the U/Ce oxalate phase (N{sub 2}H{sub 5},H){sub 2.9}U{sub 1.1}Ce{sub 0.9}(C{sub 2}O{sub 4}){sub 5}·10H{sub 2}O, synthesized using a vortex precipitator for continuous synthesis of actinide oxalates, with previously known oxalates, crystallizing in P6{sub 3}/mmc symmetry, obtained by more classical methods. This fast precipitation process induces massive nucleation of fine powders. Their structural and microstructural determination confirms that the raw and dried phases belong to the same structural family as (NH{sub 4}){sub 2}U{sub 2}(C{sub 2}O{sub 4}){sub 5}·0.7H{sub 2}O whose structure was described by Chapelet-Arab in P6{sub 3}/mmc symmetry, using single crystal data. However, they present an extended disorder inside the tunnels of the structure, even after drying at 100 °C, between water and hydrazinium ions. This disorder is directly related to the fast vortex method. This structure determination can be used as a basis for further semi-quantitative analysis on the U/minor actinides products formed under various experimental conditions. - Highlights: • Uranium cerium oxalate precipitate characterization by X-ray powder diffraction. • Morphology characterization by SEM analysis. • Structure determination by unit cell Rietveld refinement.

  15. Bloodstains on Leather: Examination of False Negatives in Presumptive Test and Human Hemoglobin Test.

    Science.gov (United States)

    Castelló, Ana; Francès, Francesc; Verdú, Fernando

    2017-09-01

    Presumptive tests for blood are very simple and sensitive tests used in the search for evidence. They also provide initial information on the nature of stains. A second test can confirm their nature. However, these tests can present false-negative results for different reasons. Some of those reasons have been studied, while others, those caused by the substrate material that contains the stain, are less well known. This work studies the effect of one component of a leather substrate-quebracho extract-on presumptive and human hemoglobin blood tests. Assays were performed using samples of blood dilutions contaminated with quebracho extract and others formed on a substrate containing the contaminant. Results show an undoubted interference that causes false negatives and even visible to the naked eye stains and also indicate that some tests (phenolphthalein) are more affected than others. Examiners should be taken into account when working on this kind of substrates. © 2017 American Academy of Forensic Sciences.

  16. Synthesis and characterization of In{sub 2}O{sub 3} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Ayeshamariam, A. [KhadirMohideen College, Adirampattinam (India); Kashif, M. [Universiti Malaysia Perlis, Perlis (Malaysia); Raja, S. Muthu [Vellore Institute of Technology, Vellore (India); Sivaranjani, S. [SBM College of Engineering and technology, Dindigul (India); Sanjeeviraja, C. [Alagappa University, Karaikudi (India); Bououdina, M. [University of Bahrain, Bahrain (Bahrain)

    2014-01-15

    Metal-oxide nanostructures have elicited increasing interest in both fundamental and applied sciences. Among metal oxide nanostructures, In{sub 2}O{sub 3} has the potential for use asa semiconductor material. This article provides details on studies carried out thus far for the synthesis and the characterization of In{sub 2}O{sub 3} nanostructures. In this research, various techniques were investigated for the fabrication of diverse and fascinating spherical shaped In{sub 2}O{sub 3} nanostructures. BrunauerEmmett-Teller (BET) analyses of the In{sub 2}O{sub 3} nanostructures through detailed refinements of the structure of the In{sub 2}O{sub 3} nanoparticles by using the Rietveld method, followed by microstructural analyses using scanning electron microscopy/ transmission electron microscopy (SEM/TEM) and a chemical composition analysis are presented and discussed. Decreasing crystallinity with an improvement in specific surface area was observed from the structural characterization. The energy dispersive analysis results showed that the as-prepared In{sub 2}O{sub 3} powder sample was stoichiometric, containing almost equal proportions of indium and oxygen. The microstructural analysis (TEM and SEM) demonstrated precise control over the diameters of the nanoparticles, which is an important advantage of the solution combustion approach.

  17. Preparation, crystallography, magnetic and magnetothermal properties of Ce<sub>5sub>SixGe>4-xsub> alloys

    Energy Technology Data Exchange (ETDEWEB)

    Vijayaraghavan, Rangarajan [Iowa State Univ., Ames, IA (United States)

    2005-01-01

    An investigation of the crystal structure and the phase relationships in the Ce<sub>5sub>Si>4-xsub>Gex> system has been carried out. The crystal structures of the single phase intermetallics were characterized using X-ray powder diffraction and subsequent refinement employing the Rietveld analysis technique was performed. The intermetallic system was found to crystallize in three distinct crystal structures. The Ce<sub>5sub>Si>4sub>-based solid solution extends from x = 0 to x = 2.15 and it was found to crystallize in the well-known Zr<sub>5sub>Si>4sub>-type tetragonal structure. The germanium rich alloys, where 3.1 ≤} x ≤ 4, crystallized in the Sm<sub>5sub>Ge>4sub>-type orthorhombic structure. The crystal structure of the intermediate phase, when 2.35 ≤ x ≤ 2.8, was found out to be of the Gd<sub>5sub>Si>2sub>Ge>2sub>-type monoclinic structure. Microhardness tests were conducted on the samples in order to probe the trend in mechanical properties in this alloy system as a function of Ge concentration. The magnetic, thermal and magnetocaloric properties of the Ce<sub>5sub>Si>4-xsub>Gex> alloy system have been investigated for x = 0, 1.0, 1.8, 2.5, 2.8, 3.5, 3.8 and 4.0. The phases with x = 0, 1.0 and 1.8 crystallize in the tetragonal Zr<sub>5sub>Si>4sub> structure and those with x = 2.5, 2.8 form in the Gd<sub>5sub>Si>2sub>Ge>2sub>-type monoclinic structure. The alloys with x = 3.5, 3.8 and 4.0 crystallize in the Sm<sub>5sub>Ge>4sub>-type orthorhombic structure. The Curie temperature of the tetragonal phases increases with increasing Ge content. The ordering temperatures of the monoclinic and orthorhombic phases remain nearly unaffected by the composition, with the Curie temperatures of the latter slightly higher than those of the former. All the alloys display evidence of antiferromagnetic interactions in the ground state. The orthorhombic and the

  18. LOGICAL REASONING ABILITY AND STUDENT PERFORMANCE IN GENERAL CHEMISTRY.

    Science.gov (United States)

    Bird, Lillian

    2010-03-01

    Logical reasoning skills of students enrolled in General Chemistry at the University of Puerto Rico in Río Piedras were measured using the Group Assessment of Logical Thinking (GALT) test. The results were used to determine the students' cognitive level (concrete, transitional, formal) as well as their level of performance by logical reasoning mode (mass/volume conservation, proportional reasoning, correlational reasoning, experimental variable control, probabilistic reasoning and combinatorial reasoning). This information was used to identify particular deficiencies and gender effects, and to determine which logical reasoning modes were the best predictors of student performance in the general chemistry course. Statistical tests to analyze the relation between (a) operational level and final grade in both semesters of the course; (b) GALT test results and performance in the ACS General Chemistry Examination; and (c) operational level and student approach (algorithmic or conceptual) towards a test question that may be answered correctly using either strategy, were also performed.

  19. Temporal Reasoning and Default Logics.

    Science.gov (United States)

    1985-10-01

    Aritificial Intelligence ", Computer Science Research Report, Yale University, forthcoming (1985). . 74 .-, A Axioms for Describing Persistences and Clipping...34Circumscription - A Form of Non-Monotonic Reasoning", Artificial Intelligence , vol. 13 (1980), pp. 27-39. [13] McCarthy, John, "Applications of...and P. J. Hayes, "Some philosophical problems from the standpoint of artificial intelligence ", in: B. Meltzer and D. Michie (eds.), Machine

  20. Facile synthesis technology of Li{sub 3}V{sub 2}(PO{sub 4}){sub 3}/C adding H{sub 2}O{sub 2} in ball mill process

    Energy Technology Data Exchange (ETDEWEB)

    Min, Xiujuan [MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, Harbin Institute of Technology, School of Chemistry and Chemical Engineering, Harbin 150001 (China); Mu, Deying [MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, Harbin Institute of Technology, School of Chemistry and Chemical Engineering, Harbin 150001 (China); Department of Environmental Engineering, Harbin University of Commerce, Harbin 150076 (China); Li, Ruhong [MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, Harbin Institute of Technology, School of Chemistry and Chemical Engineering, Harbin 150001 (China); Dai, Changsong, E-mail: changsd@hit.edu.cn [MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, Harbin Institute of Technology, School of Chemistry and Chemical Engineering, Harbin 150001 (China)

    2016-11-15

    Highlights: • Sintering time of Li{sub 3}V{sub 2}(PO{sub 4}){sub 3} reduced to 6 hours by adding hydrogen peroxide. • Electrochemical performance of Li{sub 3}V{sub 2}(PO{sub 4}){sub 3} was improved by reducing sintering time. • The Li{sub 3}V{sub 2}(PO{sub 4}){sub 3} production process was simplified during material synthesis stage. - Abstract: Li{sub 3}V{sub 2}(PO{sub 4}){sub 3}/C has stable structure, high theory specific capacity and good safety performance, therefore it has become the research focus of lithium-ion batteries in recent years. The facile synthesis technology of Li{sub 3}V{sub 2}(PO{sub 4}){sub 3}/C was characterized by adding different amounts of H{sub 2}O{sub 2}. Structure and morphology characteristics were examined by XRD, TG, Raman Spectroscopy, XPS and SEM. Electrochemical performance was investigated by constant current charging and discharging test. The results revealed that the Li{sub 3}V{sub 2}(PO{sub 4}){sub 3}/C electrochemical performance of adding 15 mL H{sub 2}O{sub 2} was better after sintering during 6 h. At the charge cut-off voltage of 4.3 V, the first discharge capacity at 0.2 C rate reached 127 mAh g{sup −1}. Because of adding H{sub 2}O{sub 2} in the ball-mill dispersant, the vanadium pentoxide formed the wet sol. The molecular-leveled mixture increased the homogeneity of raw materials. Therefore, the addition of H{sub 2}O{sub 2} shortened the sintering time and significantly improved the electrochemical performance of Li{sub 3}V{sub 2}(PO{sub 4}){sub 3}/C.

  1. Cryo Testing of tbe James Webb Space Telescope's Integrated Science Instrument Module

    Science.gov (United States)

    VanCampen, Julie

    2004-01-01

    The Integrated Science Instrument Module (ISIM) of the James Webb Space Telescope will be integrated and tested at the Environmental Test Facilities at Goddard Space Flight Center (GSFC). The cryogenic thermal vacuum testing of the ISIM will be the most difficult and problematic portion of the GSFC Integration and Test flow. The test is to validate the coupled interface of the science instruments and the ISIM structure and to sufficiently stress that interface while validating image quality of the science instruments. The instruments and the structure are not made from the same materials and have different CTE. Test objectives and verification rationale are currently being evaluated in Phase B of the project plan. The test program will encounter engineering challenges and limitations, which are derived by cost and technology many of which can be mitigated by facility upgrades, creative GSE, and thorough forethought. The cryogenic testing of the ISIM will involve a number of risks such as the implementation of unique metrology techniques, mechanical, electrical and optical simulators housed within the cryogenic vacuum environment. These potential risks are investigated and possible solutions are proposed.

  2. Sub-clinical mastitis prevalent in dairy cows in Chittagong district of Bangladesh: detection by different screening tests

    Directory of Open Access Journals (Sweden)

    Mukti Barua

    2014-07-01

    Full Text Available Aim: Mastitis is recognized as one of the most costly health disorder affecting dairy cows. An epidemiological study was carried out at some selected farms in Chittagong district of Bangladesh to determine the prevalence and risk factors of sub-clinical mastitis (SCM in dairy cows. Materials and Methods: For conducting the study, some dairy farms of Chittagong were selected from urban and periurban areas by stratified random sampling. A total of 444 quarter samples of 111 (56 from commercial dairy farms and 55 from backyards lactating dairy cows were considered. Sub-clinical mastitis (SCM was determined using three different indirect screening tests: California Mastitis Test (CMT, White Slide Test (WST and Surf Field Mastitis Test (SFMT. Sensitivity and specificity were also determined to measure the accuracy of those tests. Results: The prevalence of SCM by CMT, WST and SFMT were 32.43% (n=144, 33.56% (n=149 and 31.53% (n=140, respectively. Distribution of SCM in relation to different variables at quarter level and animal level was also recorded. The prevalence of SCM was significantly (P4 than others at quarter level. No significant difference (P>0.05 was found in relation to breed. Using CMT as a gold standard, sensitivity and specificity of WST and SFMT were also calculated at 95% confidence interval. The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, positive predictive value, negative predictive value and disease prevalence by WST and SFMT were comparable. Conclusion: This study recommends that regular screening of sub-clinical mastitis will reduce the prevalence of sub-clinical mastitis. The most effective way to control sub-clinical mastitis is to take preventive measures such as regular cleaning of the floor, keeping the udder clean, milkman's cleanliness, dry cow therapy specially in high yielding dairy cows.

  3. Increased Specificity of Wechsler Adult Intelligence Scale-Third Edition Matrix Reasoning Test Instructions and Time Limits

    Science.gov (United States)

    Callens, Andy M.; Atchison, Timothy B.; Engler, Rachel R.

    2009-01-01

    Instructions for the Matrix Reasoning Test (MRT) of the Wechsler Adult Intelligence Scale-Third Edition were modified by explicitly stating that the subtest was untimed or that a per-item time limit would be imposed. The MRT was administered within one of four conditions: with (a) standard administration instructions, (b) explicit instructions…

  4. SCRY: Enabling quantitative reasoning in SPARQL queries

    NARCIS (Netherlands)

    Meroño-Peñuela, A.; Stringer, Bas; Loizou, Antonis; Abeln, Sanne; Heringa, Jaap

    2015-01-01

    The inability to include quantitative reasoning in SPARQL queries slows down the application of Semantic Web technology in the life sciences. SCRY, our SPARQL compatible service layer, improves this by executing services at query time and making their outputs query-accessible, generating RDF data on

  5. Engineering, technology and science disciplines and gender difference: a case study among Indian students

    Science.gov (United States)

    Cheruvalath, Reena

    2018-01-01

    It is proposed to examine the argument that females cannot perform better in engineering and science fields because of their poor mathematical or logical reasoning. The major reason for the reduced number of females in the above fields in India is the socio-cultural aversion towards females choosing the field and restriction in providing higher education for them by their parents. The present study shows that the females who get the opportunity to study engineering and science perform equal to or better than their male counterparts. An analysis of CGPA (Cumulative Grade Point Average) of 2631 students who have completed their engineering or science programme in one of the top engineering colleges in India for five years shows that female academic performance is equal to or better than that of males. Mathematical, logical, verbal and mechanical reasoning are tested while calculating CGPA.

  6. Tunable luminescence properties and energy transfer in Ba{sub 3}Lu(PO{sub 4}){sub 3}:Ce{sup 3+},Tb{sup 3+} phosphors

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Cheng [Department of Physics and Electronic Engineering, Baoding University, Baoding 071002 (China); Ma, Hengxin [College of Science, Agricultural University of Hebei, Baoding 071002 (China); Liu, Yufeng, E-mail: liuyufeng4@126.com [State Key Lab of Power Systems, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China); Liu, Qingbo [Department of Physics and Electronic Engineering, Baoding University, Baoding 071002 (China); Dong, Guoyi [College of Physics Science and Technology, Hebei University, Baoding 071002 (China); Yu, Quanmao [Institute of Functional Materials, Jiangxi University of Finance and Economics, Nanchang 330013 (China)

    2014-11-15

    Highlights: • Effective energy transfer from Ce{sup 3+} to Tb{sup 3+} in Ba{sub 3}Lu(PO{sub 4}){sub 3} was confirmed. • The reason of energy transfer from Ce{sup 3+} to Tb{sup 3+} was investigated in detail. • Ba{sub 3}Lu(PO{sub 4}){sub 3}:Ce{sup 3+}, Tb{sup 3+} can be a potential green-emitting phosphor for UV LEDs. - Abstract: A series of novel color-tunable phosphors Ba{sub 3}Lu(PO{sub 4}){sub 3}:Ce{sup 3+},Tb{sup 3+} have been synthesized by solid-state reaction. X-ray diffraction, photoluminescence emission and excitation spectra, lifetime, as well as the effect of Tb{sup 3+} concentration were employed to characterize the resulting samples. The emission spectra of Ba{sub 3}Lu(PO{sub 4}){sub 3}:Ce{sup 3+},Tb{sup 3+} phosphor contains both the asymmetric broad-band Ce{sup 3+} ion emission and the line-type Tb{sup 3+} ion emission. Under ultraviolet light excitation, Ba{sub 3}Lu(PO{sub 4}){sub 3}:Ce{sup 3+},Tb{sup 3+} can achieve tunable emission from deep blue to yellowish-green by changing the concentration of Tb{sup 3+}. The results indicated that these phosphors could be considered as double emission phosphors for field emission displays.

  7. Fe-substituted (La,Sr)TiO{sub 3} as potential electrodes for symmetrical fuel cells (SFCs)

    Energy Technology Data Exchange (ETDEWEB)

    Canales-Vazquez, Jesus [Renewable Energy Research Institute, University of Castilla la Mancha, 02006 Albacete (Spain); Instituto de Ciencia de los Materiales de Barcelona, ICMAB-CSIC, 01893 Bellaterra (Spain); Ruiz-Morales, Juan Carlos; Marrero-Lopez, David; Pena-Martinez, Juan; Nunez, Pedro [Dpto. Quimica Inorganica, Universidad de La Laguna, Avda. Francisco Sanchez s/n, 38200 Tenerife, Canary Islands (Spain); Gomez-Romero, Pedro [Instituto de Ciencia de los Materiales de Barcelona, ICMAB-CSIC, 01893 Bellaterra (Spain)

    2007-09-27

    In the work presented herein, the potential use of La{sub 4}Sr{sub 8}Ti{sub 12-x}Fe{sub x}O{sub 38-{delta}} (LSTF) materials as electrodes for a new concept of solid oxide fuel cells, symmetrical fuel cells (SFCs), is considered. Such fuel cells use simultaneously the same material as anode and cathode, which notably simplifies the assembly and further maintenance of the cells. Therefore, we search for materials showing high conductivity in a wide range of oxygen partial pressures in addition to certain degree of catalytic activity for the oxidation of the fuel and reduction of the oxidant, respectively. The preliminary electrochemical experiments performed reveal that the overall conductivity increases notably upon Fe substitution, being the main contribution electronic n-type. The fuel cell tests indicate that LSTF composites with YSZ and CeO{sub 2} perform reasonably well under H{sub 2} conditions, although the performance in methane is rather modest and require further optimisation. (author)

  8. UF/sub 6/ test loop for evaluation and implementation of international enrichment plant safeguards

    International Nuclear Information System (INIS)

    Cooley, J.N.; Fields, L.W.; Swindle, D.W. Jr.

    1987-01-01

    A functional test loop capable of simulating UF/sub 6/ flows, pressures, and pipe deposits characteristic of gas centrifuge enrichment plant piping has been designed and fabricated by the Enrichment Safeguards Program of Martin Marietta Energy Systems, Inc., for use by the International Atomic Energy Agency (IAEA) at its Safeguards Analytical Laboratory in Seibersdorf, Austria. The purpose of the test loop is twofold: (1) to enable the IAEA to evaluate and to calibrate enrichment safeguards measurement instrumentation to be used in limited frequency-unannounced access (LFUA) inspection strategy measurements at gas centrifuge enrichment plants and (2) to train IAEA inspectors in the use of such instrumentation. The test loop incorporates actual sections of cascade header pipes from the centrifuge enrichment plants subject to IAEA inspections. The test loop is described, applications for its use by the IAEA are detailed, and results from an initial demonstration session using the test loop are summarized. By giving the IAEA the in-house capability to evaluate LFUA inspection strategy approaches, to develop inspection procedures, to calibrate instrumentation, and to train inspectors, the UF/sub 6/ cascade header pipe test loop will contribute to the IAEA's success in implementing LFUA strategy inspections at gas centrifuge enrichment facilities subject to international safeguards inspections

  9. What variables can influence clinical reasoning?

    Directory of Open Access Journals (Sweden)

    Vahid Ashoorion

    2012-01-01

    Full Text Available Background: Clinical reasoning is one of the most important competencies that a physician should achieve. Many medical schools and licensing bodies try to predict it based on some general measures such as critical thinking, personality, and emotional intelligence. This study aimed at providing a model to design the relationship between the constructs. Materials and Methods: Sixty-nine medical students participated in this study. A battery test devised that consist four parts: Clinical reasoning measures, personality NEO inventory, Bar-On EQ inventory, and California critical thinking questionnaire. All participants completed the tests. Correlation and multiple regression analysis consumed for data analysis. Results: There is low to moderate correlations between clinical reasoning and other variables. Emotional intelligence is the only variable that contributes clinical reasoning construct (r=0.17-0.34 (R 2 chnage = 0.46, P Value = 0.000. Conclusion: Although, clinical reasoning can be considered as a kind of thinking, no significant correlation detected between it and other constructs. Emotional intelligence (and its subscales is the only variable that can be used for clinical reasoning prediction.

  10. What variables can influence clinical reasoning?

    Science.gov (United States)

    Ashoorion, Vahid; Liaghatdar, Mohammad Javad; Adibi, Peyman

    2012-12-01

    Clinical reasoning is one of the most important competencies that a physician should achieve. Many medical schools and licensing bodies try to predict it based on some general measures such as critical thinking, personality, and emotional intelligence. This study aimed at providing a model to design the relationship between the constructs. Sixty-nine medical students participated in this study. A battery test devised that consist four parts: Clinical reasoning measures, personality NEO inventory, Bar-On EQ inventory, and California critical thinking questionnaire. All participants completed the tests. Correlation and multiple regression analysis consumed for data analysis. There is low to moderate correlations between clinical reasoning and other variables. Emotional intelligence is the only variable that contributes clinical reasoning construct (r=0.17-0.34) (R(2) chnage = 0.46, P Value = 0.000). Although, clinical reasoning can be considered as a kind of thinking, no significant correlation detected between it and other constructs. Emotional intelligence (and its subscales) is the only variable that can be used for clinical reasoning prediction.

  11. Correlation of irradiation-induced transition temperature increases from C sub v and K sub Jc /K sub Ic data

    Energy Technology Data Exchange (ETDEWEB)

    Hiser, A.L. (Materials Engineering Associates, Inc., Lanham, MD (USA))

    1990-03-01

    Reactor pressure vessel (RPV) surveillance capsules contain Charpy-V (C{sub v}) specimens, but many do not contain fracture toughness specimens; accordingly, the radiation-induced shift (increase) in the brittle-to-ductile transition region ({Delta}T) is based upon the {Delta}T determined from notch ductility (C{sub v}) tests. Since the ASME K{sub Ic} and K{sub IR} reference fracture toughness curves are shifted by the {Delta}T from C{sub v}, assurance that this {Delta}T does not underestimate {Delta}T associated with the actual irradiated fracture toughness is required to provide confidence that safety margins do not fall below assumed levels. To assess this behavior, comparisons of {Delta}T's defined by elastic-plastic fracture toughness and C{sub v} tests have been made using data from RPV base and weld metals in which irradiations were made under test reactor conditions. Using as-measure'' fracture toughness values (K{sub Jc}), average comparisons between {Delta}T(C{sub v}) and {Delta}T(K{sub Jc}) are: (a) All data: {Delta}T(K{sub Jc} 100 MPa{radical}{bar m}) = {Delta}T(C{sub v} 41 J) +10{degree}C; (b) Plates only: {Delta}T(K{sub Jc} 100 MPa{radical}{bar m}) = {Delta}T(C{sub v} 41 J) +15{degree}C; and (c) Welds only: {Delta}T(K{sub Jc} 100 MPa{radical}{bar m}) = {Delta}T(C{sub v} 41 J) {minus}1{degree}C. Fluence rate is found to have no significant effect on the relationship between {Delta}T(C{sub v}) and {Delta}T(K{sub Jc}). 12 refs., 12 figs., 5 tabs.

  12. Attitudes toward Science: Measurement and Psychometric Properties of the Test of Science-Related Attitudes for Its Use in Spanish-Speaking Classrooms

    Science.gov (United States)

    Navarro, Marianela; Förster, Carla; González, Caterina; González-Pose, Paulina

    2016-01-01

    Understanding attitudes toward science and measuring them remain two major challenges for science teaching. This article reviews the concept of attitudes toward science and their measurement. It subsequently analyzes the psychometric properties of the "Test of Science-Related Attitudes" (TOSRA), such as its construct validity, its…

  13. Experimental Study of Codeposition Electrochemistry Using Mixtures of ScCl<sub>3sub> and YCl<sub>3sub> in LiCl-KCl Eutectic Salt at 500°C

    Energy Technology Data Exchange (ETDEWEB)

    Shaltry, Michael R. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Yoo, Tae-Sic [Idaho National Lab. (INL), Idaho Falls, ID (United States); Fredrickson, Guy L. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-09-12

    Cyclic voltammetry and chronopotentiometry tests were applied to molten LiCl-KCl eutectic at 500 °C including amounts of ScCl<sub>3sub> and YCl<sub>3sub>. The purpose of the testing was to observe the effect of applied electrical current on the codeposition of scandium and yttrium, which were chosen as surrogate elements for uranium and plutonium, respectively. Features of the work were to vary the concentration of ScCl<sub>3sub> (at relatively low concentrations) as well as varying the applied current, all with a fixed concentration of YCl<sub>3sub>. Results of the experiments could provide insight of uranium electrorefining and may provide evidence, which suggests the electrorefiner could be operated at lower UCl<sub>3sub> concentration whereby codeposition (U and Pu) could be more effectively controlled.

  14. Women?s Reasons for Leaving the Engineering Field

    OpenAIRE

    Fouad, Nadya A.; Chang, Wen-Hsin; Wan, Min; Singh, Romila

    2017-01-01

    Among the different Science, Technology, Engineering, and Math fields, engineering continues to have one of the highest rates of attrition (Hewlett et al., 2008). The turnover rate for women engineers from engineering fields is even higher than for men (Frehill, 2010). Despite increased efforts from researchers, there are still large gaps in our understanding of the reasons that women leave engineering. This study aims to address this gap by examining the reasons why women leave engineering. ...

  15. Spatial Reasoning and Understanding the Particulate Nature of Matter: A Middle School Perspective

    Science.gov (United States)

    Cole, Merryn L.

    This dissertation employed a mixed-methods approach to examine the relationship between spatial reasoning ability and understanding of chemistry content for both middle school students and their science teachers. Spatial reasoning has been linked to success in learning STEM subjects (Wai, Lubinski, & Benbow, 2009). Previous studies have shown a correlation between understanding of chemistry content and spatial reasoning ability (e.g., Pribyl & Bodner, 1987; Wu & Shah, 2003: Stieff, 2013), raising the importance of developing the spatial reasoning ability of both teachers and students. Few studies examine middle school students' or in-service middle school teachers' understanding of chemistry concepts or its relation to spatial reasoning ability. The first paper in this dissertation addresses the quantitative relationship between mental rotation, a type of spatial reasoning ability, and understanding a fundamental concept in chemistry, the particulate nature of matter. The data showed a significant, positive correlation between scores on the Purdue Spatial Visualization Test of Rotations (PSVT; Bodner & Guay, 1997) and the Particulate Nature of Matter Assessment (ParNoMA; Yezierski, 2003) for middle school students prior to and after chemistry instruction. A significant difference in spatial ability among students choosing different answer choices on ParNoMA questions was also found. The second paper examined the ways in which students of different spatial abilities talked about matter and chemicals differently. Students with higher spatial ability tended to provide more of an explanation, though not necessarily in an articulate matter. In contrast, lower spatial ability students tended to use any keywords that seemed relevant, but provided little or no explanation. The third paper examined the relationship between mental reasoning and understanding chemistry for middle school science teachers. Similar to their students, a significant, positive correlation between

  16. Science and Religion in Liberal Democracy

    DEFF Research Database (Denmark)

    Jønch-Clausen, Karin

    The dissertation explores the role of scientific rationality and religious reasoning in democratic law and policymaking. How does legitimate law and policymaking proceed in light of disagreements on science and religion? This question is addressed within the framework of public reason. Roughly pu...... concerning the role science and religion in political deliberation challenge the public reason framework as viable vehicle for pursuing democratic legitimacy? The dissertation discusses these and other questions related to the special role of science and religion in liberal democracy....

  17. Implementation science: a role for parallel dual processing models of reasoning?

    Directory of Open Access Journals (Sweden)

    Phillips Paddy A

    2006-05-01

    Full Text Available Abstract Background A better theoretical base for understanding professional behaviour change is needed to support evidence-based changes in medical practice. Traditionally strategies to encourage changes in clinical practices have been guided empirically, without explicit consideration of underlying theoretical rationales for such strategies. This paper considers a theoretical framework for reasoning from within psychology for identifying individual differences in cognitive processing between doctors that could moderate the decision to incorporate new evidence into their clinical decision-making. Discussion Parallel dual processing models of reasoning posit two cognitive modes of information processing that are in constant operation as humans reason. One mode has been described as experiential, fast and heuristic; the other as rational, conscious and rule based. Within such models, the uptake of new research evidence can be represented by the latter mode; it is reflective, explicit and intentional. On the other hand, well practiced clinical judgments can be positioned in the experiential mode, being automatic, reflexive and swift. Research suggests that individual differences between people in both cognitive capacity (e.g., intelligence and cognitive processing (e.g., thinking styles influence how both reasoning modes interact. This being so, it is proposed that these same differences between doctors may moderate the uptake of new research evidence. Such dispositional characteristics have largely been ignored in research investigating effective strategies in implementing research evidence. Whilst medical decision-making occurs in a complex social environment with multiple influences and decision makers, it remains true that an individual doctor's judgment still retains a key position in terms of diagnostic and treatment decisions for individual patients. This paper argues therefore, that individual differences between doctors in terms of

  18. B<sub>12sub>P>2sub>: Improved Epitaxial Growth and Evaluation of Alpha Irradiation on its Electrical Transport Properties

    Energy Technology Data Exchange (ETDEWEB)

    Frye, Clint D. [Kansas State Univ., Manhattan, KS (United States)

    2016-10-17

    The wide bandgap (3.35 eV) semiconductor icosahedral boron phosphide (B<sub>12sub>P>2sub>) has been reported to self-heal from radiation damage from β particles (electrons) with energies up to 400 keV by demonstrating no lattice damage using transmission electron microscopy. This property could be exploited to create radioisotope batteries–semiconductor devices that directly convert the decay energy from a radioisotope to electricity. Such devices potentially have enormous power densities and decades-long lifetimes. To date, the radiation hardness of B<sub>12sub>P>2sub> has not been characterized by electrical measurements nor have B<sub>12sub>P>2sub> radioisotope batteries been realized. Therefore, this study was undertaken to evaluate the radiation hardness of B<sub>12sub>P>2sub> after improving its epitaxial growth, developing ohmic electrical contacts, and reducing the residual impurities. Subsequently, the effects of radiation from a radioisotope on the electrical transport properties of B<sub>12sub>P>2sub> were tested.

  19. Imminent: Irradiation Testing of (Th,Pu)O{sub 2} Fuel - 13560

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, Julian F. [Thor Energy AS, Sommerrogaten 13-15, Oslo 0255 (Norway); Franceschini, Fausto [Westinghouse Electric Company LLC, 1000 Cranberry Woods Drive, Cranberry Township, PA 16066 (United States)

    2013-07-01

    Commercial-prototype thorium-plutonium oxide (Th-MOX) fuel pellets have been loaded into the material test reactor in Halden, Norway. The fuel is being operated at full power - with instrumentation - in simulated LWR / PHWR conditions and its behaviour is measured 'on-line' as it operates to high burn-up. This is a vital test on the commercialization pathway for this robust new thoria-based fuel. The performance data that is collected will support a fuel modeling effort to support its safety qualification. Several different samples of Th-MOX fuel will be tested, thereby collecting information on ceramic behaviours and their microstructure dependency. The fuel-cycle reasoning underpinning the test campaign is that commercial Th- MOX fuels are an achievable intermediate / near-term SNF management strategy that integrates well with a fast reactor future. (authors)

  20. Intertwining evidence- and model-based reasoning in physics sensemaking: An example from electrostatics

    Science.gov (United States)

    Russ, Rosemary S.; Odden, Tor Ole B.

    2017-12-01

    Our field has long valued the goal of teaching students not just the facts of physics, but also the thinking and reasoning skills of professional physicists. The complexity inherent in scientific reasoning demands that we think carefully about how we conceptualize for ourselves, enact in our classes, and encourage in our students the relationship between the multifaceted practices of professional science. The current study draws on existing research in the philosophy of science and psychology to advocate for intertwining two important aspects of scientific reasoning: using evidence from experimentation and modeling. We present a case from an undergraduate physics course to illustrate how these aspects can be intertwined productively and describe specific ways in which these aspects of reasoning can mutually reinforce one another in student learning. We end by discussing implications for this work for instruction in introductory physics courses and for research on scientific reasoning at the undergraduate level.

  1. MnFe{sub 2}O{sub 4} as a gas sensor towards SO{sub 2} and NO{sub 2} gases

    Energy Technology Data Exchange (ETDEWEB)

    Rathore, Deepshikha, E-mail: deep.nano@gmail.com; Mitra, Supratim [Department of Natural Sciences, NIIT University, Neemrana, Rajasthan 301705 (India)

    2016-05-06

    The chemical co-precipitation method was used to synthesize MnFe{sub 2}O{sub 4} nanoparticles. Single cubic phase formation of nanoparticles was confirmed by X-ray diffraction technique. The average particle size of MnFe{sub 2}O{sub 4} nanoparticles was found to be 10.7 nm using Scherrer formula. The ultrafine powder of MnFe{sub 2}O{sub 4} nanoparticles was pressed to design pellet of 10 mm diameter and 1mm thickness. Copper electrodes have been deposited on the surface of pellet using silver paste in the form of capacitor. Fabricated gas sensing device of MnFe{sub 2}O{sub 4} nanoparticles was tested towards SO{sub 2} and NO{sub 2} gases. Cole-Cole plot of MnFe{sub 2}O{sub 4} was investigated with the help of electrochemical workstation. The performance of the sensors including sensitivity, response and recovery time was also determined. It was observed that the MnFe{sub 2}O{sub 4} nanoparticles are more sensible for NO{sub 2} gas as compared to SO{sub 2} gas.

  2. Thermal properties of GdSr{sub 2}RuCu{sub 2}O{sub 8-{delta}} based mixtures in the GdSr{sub 2}RuO{sub 6}-CuO pseudo-binary system

    Energy Technology Data Exchange (ETDEWEB)

    Gombos, Marcello [Laboratorio Regionale Supermat CNR-INFM Via Salvador Allende, I-84081 Baronissi (Italy); Dipartimento di Fisica ' E.R.Caianiello' , Universita di Salerno, Via Salvador Allende, I-84081 Baronissi (Italy)], E-mail: gombos@sa.infn.it; Ciancio, Regina; Vecchione, Antonio; Pace, Sandro [Laboratorio Regionale Supermat CNR-INFM Via Salvador Allende, I-84081 Baronissi (Italy); Dipartimento di Fisica ' E.R.Caianiello' , Universita di Salerno, Via Salvador Allende, I-84081 Baronissi (Italy)

    2007-09-01

    GdSr{sub 2}RuCu{sub 2}O{sub 8-{delta}} (Gd1212) rutheno-cuprate compound is widely studied because it shows the coexistence of superconductivity and highly anisotropic magnetic ordering in the same cell. Anyway the nature of the magnetic ordering is still debated and the fabrication of macroscopic samples oriented along a crystallographic axis, that could help to clarify its details, appears to be quite difficult. For this reason, accurate investigation on Gd1212 incongruent melting reaction, producing liquid copper oxide and the solid GdSr{sub 2}RuO{sub 6} (Gd1210), appears to be necessary to improve the fabrication of crystallographically oriented bulk superconducting samples. Thermo-gravimetric and differential thermal measurements were performed to analyse the thermal behaviour up to 1200 deg. C and the melting temperatures of different mixtures of Gd1212 with Gd1210 or CuO, in view to perform a scan of the whole CuO-Gd1212-Gd1210 coexistence line of the Gd-Sr-Ru-Cu-O phase diagram. Dependence on the atmosphere and the formation of different spurious phases was also studied.

  3. Secondary School Students' Understanding of Science and Their Socioscientific Reasoning

    Science.gov (United States)

    Karahan, Engin; Roehrig, Gillian

    2017-01-01

    Research in socioscientific issue (SSI)-based interventions is relatively new (Sadler in "Journal of Research in Science Teaching" 41:513-536, 2004; Zeidler et al. in "Journal of Research in Science Teaching" 46:74-101, 2009), and there is a need for understanding more about the effects of SSI-based learning environments…

  4. Performance-based assessment of scientific reasoning in children

    NARCIS (Netherlands)

    Lazonder, A.W.; Janssen, N.

    2017-01-01

    Recent longitudinal and cross-sectional studies have examined how scientific reasoning skills such as experimenting, making inferences and evaluating evidence develop in young science learners. Results, although informative, likely underestimate children’s true capabilities because data in these

  5. Rational construction of Z-scheme Ag{sub 2}CrO{sub 4}/g-C{sub 3}N{sub 4} composites with enhanced visible-light photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Jin, E-mail: lj328520504@126.com; Zhou, Xiaosong; Ma, Lin; Xu, Xuyao

    2016-12-30

    Highlights: • Novel visible-light driven Ag{sub 2}CrO{sub 4}/g-C{sub 3}N{sub 4} composites were synthesized. • Ag{sub 2}CrO{sub 4}/g-C{sub 3}N{sub 4} exhibited enhanced visible-light photocatalytic activity. • The reasons for the enhanced photocatalytic activity were revealed. - Abstract: Novel visible-light driven Z-scheme Ag{sub 2}CrO{sub 4}/g-C{sub 3}N{sub 4} composites with different contents of Ag{sub 2}CrO{sub 4} were fabricated by a facile chemical precipitation method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV–vis diffuse reflectance spectroscopy (UV-vis DRS), photoluminescence (PL) spectroscopy and photoelectrochemical measurements. Compared with individual g-C{sub 3}N{sub 4} and Ag{sub 2}CrO{sub 4}, the Ag{sub 2}CrO{sub 4}/g-C{sub 3}N{sub 4} composites displayed much larger photocatalytic activities for the photocatalytic degradation of methyl orange (MO) solution at room temperature under visible light irradiation (λ > 420 nm). Importantly, the optimum photodegradation rate constant of the Ag{sub 2}CrO{sub 4}/g-C{sub 3}N{sub 4} composite at a theoretical weight content of 8.0% Ag{sub 2}CrO{sub 4} for the photodegradation of MO was 0.0068 min{sup −1}, which was 5.7 and 4.3 times higher than that of pure g-C{sub 3}N{sub 4} and Ag{sub 2}CrO{sub 4}, respectively. Such enormous enhancement in photocatalytic performance was predominantly ascribed to the efficient separation and transfer of photogenerated electrons and holes at the Ag{sub 2}CrO{sub 4}/g-C{sub 3}N{sub 4} interface imparted through the Z-scheme electron transfer. Furthermore, radical trap experiments depicted that both the holes and superoxide radical anions were thought to dominate oxidative species of the Ag{sub 2}CrO{sub 4}/g-C{sub 3}N{sub 4} composite for MO degradation under visible light irradiation. Ultimately, a tentative Z-scheme photodegradation mechanism

  6. The English Proficiency Test of the Iranian Ministry of Science, Research, and Technology: A Review

    Directory of Open Access Journals (Sweden)

    Mahdieh Noori

    2017-08-01

    Full Text Available One of the serious decisions which every administrator may need to make during his/her professional career is to select or reject applicants based on their general language skills or competence. These significant decisions, which may be of serious consequences not only for the individuals but also for the society in general, are occasionally made based on norm-referenced proficiency tests. Out of internationally available proficiency tests such as the TOEFL test, those which fit the specific local cultural and academic contexts seem of greater prominence. One such test, which has been specifically designed for the Iranian EFL context by the Ministry of Science, Research, and Technology, is the MSRT proficiency test. While a few studies have been conducted on the analysis of the reliability and validity of the mentioned test, no study has yet reviewed the test and its component parts. Therefore, the current study aimed at considering the strengths and weaknesses of the test in general and its component items in particular. The results implicated that the MSRT benefits from more efficient general reliability and validity, well planned language items, practicality, ease of administration, objective scoring, ease of accessibility, as well as reasonable fees, while it needs to be more substantiated in terms of the inclusion of the speaking skill assessment, the computerized adaptive assessment procedures, and the correction factor for guessing. In addition, the use of the individual-based listening apparatus for testing listening comprehension as well as the consideration of the integrative communicative tests for its concurrent validity purposes can contribute to more appropriate distinction of proficient and non-proficient applicants.

  7. Theoretical studies of the local structure and electron paramagnetic resonance parameters for tetragonal VO{sup 2+} in C{sub 6}H{sub 7}KO{sub 7}

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Ping [Chongqing Jiaotong Univ. (China). School of Science; Li, Ling [Sichuan University of Arts and Science, Dazhou (China). Dept. of Maths and Finance-Economics

    2015-07-01

    The optical spectra, electron paramagnetic resonance parameters (i.e., the spin Hamiltonian parameters, including paramagnetic g factors and the hyperfine structure constants A{sub i}) and the local distortion structure for the tetragonal VO{sup 2+} in C{sub 6}H{sub 7}KO{sub 7} are theoretically studied based on the crystal-field theory and three-order perturbation formulas of a 3d{sup 1} centre in tetragonal site. The magnitude of orbital reduction factor, core polarisation constant κ, and local structure parameters are obtained by fitting the calculated optical spectra and electron paramagnetic resonance parameters to the experimental values. The theoretical results are in reasonable agreement with the experimental values.

  8. Characterisation of Pb(Mn{sub 1/3}Nb{sub 2/3})O{sub 3} ceramics by SEM, XRD, XPS and dielectric permittivity tests

    Energy Technology Data Exchange (ETDEWEB)

    Molak, A. [Institute of Physics, University of Silesia, Ul. Uniwersytecka 4, PL-40-007 Katowice (Poland)]. E-mail: molak@us.edu.pl; Talik, E. [Institute of Physics, University of Silesia, Ul. Uniwersytecka 4, PL-40-007 Katowice (Poland); Kruczek, M. [Institute of Physics, University of Silesia, Ul. Uniwersytecka 4, PL-40-007 Katowice (Poland); Paluch, M. [Institute of Physics, University of Silesia, Ul. Uniwersytecka 4, PL-40-007 Katowice (Poland); Ratuszna, A. [Institute of Physics, University of Silesia, Ul. Uniwersytecka 4, PL-40-007 Katowice (Poland); Ujma, Z. [Institute of Physics, University of Silesia, Ul. Uniwersytecka 4, PL-40-007 Katowice (Poland)

    2006-03-15

    The Pb(Mn{sub 1/3}Nb{sub 2/3})O{sub 3} ceramics has been obtained from oxides by sintering in air, using a two-stage process with precursor columbite-like (Mn{sub 0.5}Nb)O{sub 3} phase. The PbO oxide was added in the second stage. Analysis of the X-ray diffraction pattern shows that the ceramics consist of 91% of major perovskite phase. A monoclinic distortion of the perovskite structure was found. The cell parameters are a = 12.193(3) A, b = 11.966(6) A, c 12.144(2) A, {beta} = 90{sup o}10.7'. The microanalysis made with SEM exhibited fluctuation in chemical composition of the perovskite phase. Precipitation of MnO{sub 2}, PbO and the Pb-Mn-Nb-O phase different from perovskite was found. The X-ray photoelectron spectroscopy was used to study the electronic structure of the Pb(Mn{sub 1/3}Nb{sub 2/3})O{sub 3} ceramics. The core levels of lead, manganese, niobium and oxygen were measured. The shape of valence band ridge is influenced by Mn 3d states. The real average chemical composition obtained from the XPS measurement is Pb{sub 0.99}(Mn{sub 0.42}Nb{sub 0.67})O{sub 2.92}. Broadband dielectric measurement was carried out in 10{sup -2} to 10{sup 6} Hz and within 80-700 K ranges. The dominant relaxation process exhibits characteristic times typical for ionic processes {tau} {sub 0,H} = 1 x 10{sup -11} s for the higher temperature range and, {tau} {sub 0,L} = 1 x 10{sup -9} s for lower temperatures. The activation energy of relaxation process, E {sub M,H} = 0.43 eV and E {sub M,L} = 0.34 eV corresponds to activation energy of electric conductivity. The dielectric relaxation is ascribed to dipoles created by oxygen vacancies and/or Mn-V {sub O} complexes.

  9. Determinants of the accuracy of nursing diagnoses: influence of ready knowledge, knowledge sources, disposition toward critical thinking, and reasoning skills.

    Science.gov (United States)

    Paans, Wolter; Sermeus, Walter; Nieweg, Roos; van der Schans, Cees

    2010-01-01

    The purpose of this study was to determine how knowledge sources, ready knowledge, and disposition toward critical thinking and reasoning skills influence the accuracy of student nurses' diagnoses. A randomized controlled trial was conducted to determine the influence of knowledge sources. We used the following questionnaires: (a) knowledge inventory, (b) California Critical Thinking Disposition Inventory, and (c) Health Science Reasoning Test (HSRT). The use of knowledge sources had very little influence on the accuracy of nursing diagnoses. Accuracy was significantly related to the analysis domain of the HSRT. Students were unable to operationalize knowledge sources to derive accurate diagnoses and did not effectively use reasoning skills. Copyright 2010 Elsevier Inc. All rights reserved.

  10. Scaffolding Student Learning in the Discipline-Specific Knowledge through Contemporary Science Practices: Developing High-School Students' Epidemiologic Reasoning through Data Analysis

    Science.gov (United States)

    Oura, Hiroki

    Science is a disciplined practice about knowing puzzling observations and unknown phenomena. Scientific knowledge of the product is applied to develop technological artifacts and solve complex problems in society. Scientific practices are undeniably relevant to our economy, civic activity, and personal lives, and thus public education should help children acquire scientific knowledge and recognize the values in relation to their own lives and civil society. Likewise, developing scientific thinking skills is valuable not only for becoming a scientist, but also for becoming a citizen who is able to critically evaluate everyday information, select and apply only the trustworthy, and make wise judgments in their personal and cultural goals as well as for obtaining jobs that require complex problem solving and creative working in the current knowledge-based economy and rapid-changing world. To develop students' scientific thinking, science instruction should focus not only on scientific knowledge and inquiry processes, but also on its epistemological aspects including the forms of causal explanations and methodological choices along with epistemic aims and values under the social circumstances in focal practices. In this perspective, disciplinary knowledge involves heterogeneous elements including material, cognitive, social, and cultural ones and the formation differs across practices. Without developing such discipline-specific knowledge, students cannot enough deeply engage in scientific "practices" and understand the true values of scientific enterprises. In this interest, this dissertation explores instructional approaches to make student engagement in scientific investigations more authentic or disciplinary. The present dissertation work is comprised of three research questions as stand-alone studies written for separate publication. All of the studies discuss different theoretical aspects related to disciplinary engagement in epidemiologic inquiry and student

  11. Control of Sulfidogenesis Through Bio-oxidation of H<sub>2sub>S Coupled to (per)chlorate Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Gregoire, Patrick [Univ. of California, Berkeley, CA (United States); Engelbrektson, Anna [Univ. of California, Berkeley, CA (United States); Hubbard, Christopher G. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Metlagel, Zoltan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Csencsits, Roseann [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Auer, Manfred [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Conrad, Mark E. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Thieme, Jurgen [Brookhaven National Lab. (BNL), Upton, NY (United States); Northrup, Paul [Brookhaven National Lab. (BNL), Upton, NY (United States); Coates, John D. [Univ. of California, Berkeley, CA (United States)

    2014-04-04

    Here, we investigate H<sub>2sub>S attenuation by dissimilatory perchlorate-reducing bacteria (DPRB). All DPRB tested oxidized H<sub>2sub>S coupled to (per)chlorate reduction without sustaining growth. H<sub>2sub>S was preferentially utilized over organic electron donors resulting in an enriched (34S)-elemental sulfur product. Electron microscopy revealed elemental sulfur production in the cytoplasm and on the cell surface of the DPRB Azospira suillum. We also propose a novel hybrid enzymatic-abiotic mechanism for H<sub>2sub>S oxidation similar to that recently proposed for nitrate-dependent Fe(II) oxidation. The results of this study have implications for the control of biosouring and biocorrosion in a range of industrial environments.

  12. Preparation of nanocrystalline Ce{sub 1−x}Sm{sub x}(Fe,Co){sub 11}Ti by melt spinning and mechanical alloying

    Energy Technology Data Exchange (ETDEWEB)

    Wuest, H., E-mail: holger.wuest@de.bosch.com [Robert Bosch GmbH, Postfach 10 60 50, 70049 Stuttgart (Germany); Bommer, L., E-mail: lars.bommer@de.bosch.com [Robert Bosch GmbH, Postfach 10 60 50, 70049 Stuttgart (Germany); Huber, A.M., E-mail: arne.huber@de.bosch.com [Robert Bosch GmbH, Postfach 10 60 50, 70049 Stuttgart (Germany); Goll, D., E-mail: dagmar.goll@htw-aalen.de [Aalen University, Materials Research Institute, Beethovenstr. 1, 73430 Aalen (Germany); Weissgaerber, T., E-mail: thomas.weissgaerber@ifam-dd.fraunhofer.de [Fraunhofer Institute for Manufacturing Technology and Advanced Materials (IFAM), Branch Lab Dresden, Winterbergstraße 28, 01277 Dresden (Germany); Kieback, B., E-mail: bernd.kieback@ifam-dd.fraunhofer.de [Fraunhofer Institute for Manufacturing Technology and Advanced Materials (IFAM), Branch Lab Dresden, Winterbergstraße 28, 01277 Dresden (Germany); Technische Universität Dresden, Institute for Materials Science, Helmholtzstraße 7, 01069 Dresden (Germany)

    2017-04-15

    Permanent magnetic materials based on Ce(Fe, Co){sub 12−x}Ti{sub x} with the ThMn{sub 12} structure are promising candidates for replacing NdFeB magnets. Its intrinsic magnetic properties are not far below the values of Nd{sub 2}Fe{sub 14}B, and the high amount of Fe and the fact that Ce is much more abundant and less expensive than Nd encourages the reasonable interest in these compounds. Nanocrystalline magnetic material of the composition Ce{sub 1−x}Sm{sub x}Fe{sub 11−y}Co{sub y}Ti (x=0−1 and y=0; 1.95) has been produced by both melt spinning and mechanical alloying. Alloys containing only Ce as rare earth element (x=0) show coercivities below 77 kA/m, while for x=1 H{sub c,J} values up to 392 kA/m are reached. Coercivity shows rather an exponential than a linear dependence on the gradual substitution of Ce by Sm. - Highlights: • CeFe{sub 11}Ti nanocrystalline samples demonstrate values of H{sub c,J} up to 77 kA/m. • SmFe{sub 11}Ti nanocrystalline samples demonstrate values of H{sub c,J} up to 392 kA/m. • Dependence of H{sub c,J} on x in Ce{sub 1−x}Sm{sub x(}Fe, Co){sub 11}Ti obeys non-linear dependence. • Optimum annealing shifts to from 800 °C for CeFe{sub 11}Ti to 900 °C for SmFe{sub 11}Ti.

  13. Performance Test of the Salt transfer and Pellet fabrication of UCl{sub 3} Making Equipment for Electrorefining

    Energy Technology Data Exchange (ETDEWEB)

    Woo, M. S.; Jin, H. J.; Park, G. I.; Park, S. B. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    The process to produce a uranium chloride salt includes two steps: a reaction process of gaseous chlorine with liquid cadmium to form the CdCl{sub 2} occurring in a Cd layer, followed by a process to produce UCl{sub 3} by the reaction of U in the LiCl-KCl eutectic salt and CdCl{sub 2}. Chemical reaction is next chlorination reaction; - Cd chlorination : Cd + Cl2 → CdCl{sub 2} - U chlorination : 3CdCl2 + 2U → 3Cd + 2UCl{sub 3} The apparatus for producing UCl{sub 3} consists of a chlorine gas generator, a uranium chlorinator, a Cd distiller, the pelletizer, a off-gas wet scrubber and a dry scrubber. Salt transfer system set among reactors to transfer salt at 500 .deg. C. The temperature of the reactants is maintained at about 600 .deg. C. After the reaction is completed in the uranium chlorinator, The Salt product is transferred to the Cd distiller to decrease residual Cd concentration in the salts, and then salt is transferred to the mould of pelletizer by a transfer system to fabricate pellet type salt. Performance test of the salt transfer and pellet fabrication of its equipment was tested in this work. Performance test of the salt transfer and pellet fabrication of UCl3 making equipment for Electrorefining carried out in this work. The result of equipment test is that melted salt at 600 .deg. C was easy transferred by salt transfer equipment heated at 500 .deg. C. In this time, salt transfer was carried out by argon gas pressurization at 3bar. When velocity of salt transfer was controlled under reduce pressure, velocity of salt transfer was difficult to control. And when salt pellet was fabricated by the mold of pelletizer heated at 90 .deg. C better than mold of pelletizer heated at 200 .deg. C because salt melted prevent leakage from mold of pelletizer.

  14. Testing for structural changes in large portfolios

    OpenAIRE

    Posch, Peter N.; Ullmann, Daniel; Wied, Dominik

    2015-01-01

    Model free tests for constant parameters often fail to detect structural changes in high dimensions. In practice, this corresponds to a portfolio with many assets and a reasonable long time series. We reduce the dimensionality of the problem by looking a compressed panel of time series obtained by cluster analysis and the principal components of the data. Using our methodology we are able to extend a test for a constant correlation matrix from a sub portfolio to whole indices a...

  15. The Application of Supercritical CO{sub 2} Power Cycle to Various Nuclear Systems

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Ik [KAIST, Daejeon (Korea, Republic of)

    2015-10-15

    The main reason why the S-CO{sub 2} Brayton cycle has these advantages is that the compressor operates near the critical point of CO{sub 2} (30.98 .deg. C, 7.38MPa) to reduce the compression work significantly compared to the other Brayton cycles. In this paper, various applications of supercritical CO{sub 2} power cycle to nuclear systems will be presented and summarized. The S-CO{sub 2} cycle can achieve relatively high efficiency within the mild turbine inlet temperature range (450 - 850 .deg. C) compared with other power conversion systems. The main benefit of the S-CO{sub 2} cycle is the small size of the overall system and its application includes not only the next generation nuclear reactors but also conventional water-cooled reactors too. Various layouts were compared and the recompression cycle shows the best efficiency. The layout is suitable for application to advanced nuclear reactor systems. To evaluate the S-CO{sub 2} cycle performance, various countries constructed and demonstrated S-CO{sub 2} integral system test loops and similar research works are ongoing in Korea as well. However, to evaluate the commercial S-CO{sub 2} power systems, development of a large scale (> 10 MW) prototype S-CO{sub 2} system is necessary.

  16. Measuring CO <sub>2sub> and N <sub>2sub> O Mass Transfer into GAP-1 CO <sub>2sub> –Capture Solvents at Varied Water Loadings

    Energy Technology Data Exchange (ETDEWEB)

    Whyatt, Greg A.; Zwoster, Andy; Zheng, Feng; Perry, Robert J.; Wood, Benjamin R.; Spiry, Irina; Freeman, Charles J.; Heldebrant, David J.

    2017-04-12

    This paper investigates the CO<sub>2sub> and N<sub>2sub> O absorption behavior in the water-lean gamma amino propyl (GAP)-1/TEG solvent system using a wetted-wall contactor. Testing was performed on a blend of GAP-1 aminosilicone in triethylene glycol at varied water loadings in the solvent. Measurements were made with CO<sub>2sub> and N<sub>2sub> O at representative lean (0.04 mol CO<sub>2sub>/mol alkalinity), middle (0.13 mol CO<sub>2sub> /mol alkalinity) and rich (0.46 mol CO<sub>2sub> /mol alkalinity) solvent loadings at 0, 5, 10 and 15 wt% water loadings at 40, 60 and 80C° and N<sub>2sub> O at (0.08-0.09 mol CO<sub>2sub> /mol alkalinity) at 5 wt% water at 40, 60 and 80C°. CO<sub>2sub> flux was found to be non-linear with respect to log mean pressure driving force (LMPD). Liquid-film mass transfer coefficients (k'g) were calculated by subtracting the gas film resistance (determined from a correlation from literature) from the overall mass transfer measurement. The resulting k'g values for CO<sub>2sub> and N<sub>2sub> O in GAP-1/TEG mixtures were found to be higher than that of 5M aqueous monoethanolamine under comparable driving force albeit at higher solvent viscosities. The k'g values for CO<sub>2sub> were also found to decrease with increasing solvent water content and increase with a decrease in temperature. These observations indicate that mass transfer of CO<sub>2sub> in GAP-1/TEG is linked to the physical solubility of CO<sub>2sub> , which is higher in organic solvents compared to water. This paper expands on the understanding of the unique mass transfer behavior and kinetics of CO<sub>2sub> capture in water-lean solvents.

  17. Testing Measurement Invariance of the Students' Affective Characteristics Model across Gender Sub-Groups

    Science.gov (United States)

    Demir, Ergül

    2017-01-01

    In this study, the aim was to construct a significant structural measurement model comparing students' affective characteristics with their mathematic achievement. According to this model, the aim was to test the measurement invariances between gender sub-groups hierarchically. This study was conducted as basic and descriptive research. Secondary…

  18. Electrochemical properties of LaNi{sub 4.2}Co{sub 0.4}Zn{sub 0.1}Al{sub 0.3} and LaNi{sub 4.3}Co{sub 0.4}Zn{sub 0.1}Al{sub 0.2} alloys as anode materials for Ni-MH batteries

    Energy Technology Data Exchange (ETDEWEB)

    Giza, Krystyna [Czestochowa Univ. of Technology (Poland). Faculty of Production Engineering and Materials Technology

    2017-07-01

    The galvanostatic charge and discharge technique was used for the evaluation of the changes in electrochemical parameters of the tested metal hydride electrodes during the repeated hydrogen absorption and desorption processes. Higher development of the effective surface area during hydrogenation has been obtained for LaNi{sub 4.3}Co{sub 0.4}Zn{sub 0.1}Al{sub 0.2} composite electrode. For the conditions of current ± 0.5 C, the discharge capacities of LaNi{sub 4.2}Co{sub 0.4}Zn{sub 0.1}Al{sub 0.3} and LaNi{sub 4.3}Co{sub 0.4}Zn{sub 0.1}Al{sub 0.2} alloys are 240 and 316 mAh x g{sup -1}, respectively. From the point of view of improving the kinetics of the process of charge transfer at the electrode/electrolyte interface as well as a resistance to self-discharging, a partial substitution of nickel with zinc in the LaNi{sub 4.3}Co{sub 0.4}Al{sub 0.3} alloy is not favorable.

  19. New transcritical CO{sub 2} compressor series; Neue transkritische CO{sub 2}-Verdichterbaureihe

    Energy Technology Data Exchange (ETDEWEB)

    Froeschle, Manuel [GEA Bock GmbH, Frickenhausen (Germany)

    2011-10-15

    The use of natural refrigerants that is recently discussed, is not a new development, but has grown in importance in the last few years. Particularly in the supermarket- and heat pump area, a growing demand in CO{sub 2}-systems for subcritical and transcritical applications could be observed. An extension of the CO{sub 2} components in this area is therefore absolutely necessary. For this reason a completely new transcritical compressor series for maximum pressures of up to 150 bar and extended capacity stages was developed especially. (orig.)

  20. Facile one-pot construction of α-Fe{sub 2}O{sub 3}/g-C{sub 3}N{sub 4} heterojunction for arsenic removal by synchronous visible light catalysis oxidation and adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Suwen; Ji, Chunnuan, E-mail: 1842355613@qq.com; Wu, Lingling; Chi, Shenghua; Qu, Rongjun; Li, Yan; Lu, Yangxiao; Sun, Changmei; Xue, Zhongxin

    2017-06-15

    α-Fe{sub 2}O{sub 3}/g-C{sub 3}N{sub 4} composites with heterojunction were prepared by facile one-pot synthesis using ferric chloride and dicyandiamide as precursors. The newly formed composites were applied to remove arsenic from aqueous solution for the first time through synchronous visible light catalysis oxidation and adsorption. α-Fe{sub 2}O{sub 3}/g-C{sub 3}N{sub 4} composites were characterized by wide-angle X-ray powder diffraction, transmission electron microscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, UV–Vis diffuse reflectance spectroscopy, and BET surface analysis. Under visible light irradiation, As(III) was oxidized to As(V) efficiently on the surface of α-Fe{sub 2}O{sub 3}/g-C{sub 3}N{sub 4}. In addition, the oxidized arsenic could be adsorbed in situ, resulting in the effective arsenic removal. The enhancement of photocatalytic activity the composites was attributed to the construction of heterojunction between α-Fe{sub 2}O{sub 3} and g-C{sub 3}N{sub 4}. A possible oxidation mechanism of the as-composites for As(III) under visible light irradiation was also elucidated. - Highlights: • α-Fe{sub 2}O{sub 3}/g-C{sub 3}N{sub 4} composites with heterojunction was prepared by facile one-pot synthesis. • The photocatalytic activity of α-Fe{sub 2}O{sub 3}/g-C{sub 3}N{sub 4} composites under visible light irradiation for As(III) was evaluated. • Synchronous visible light catalysis oxidation and adsorption were achieved for the removal of arsenic. • The reasonable oxidation mechanism of the composites for As(III) under visible light irradiation was investigated.

  1. Women's Reasons for Leaving the Engineering Field.

    Science.gov (United States)

    Fouad, Nadya A; Chang, Wen-Hsin; Wan, Min; Singh, Romila

    2017-01-01

    Among the different Science, Technology, Engineering, and Math fields, engineering continues to have one of the highest rates of attrition (Hewlett et al., 2008). The turnover rate for women engineers from engineering fields is even higher than for men (Frehill, 2010). Despite increased efforts from researchers, there are still large gaps in our understanding of the reasons that women leave engineering. This study aims to address this gap by examining the reasons why women leave engineering. Specifically, we analyze the reasons for departure given by national sample of 1,464 women engineers who left the profession after having worked in the engineering field. We applied a person-environment fit theoretical lens, in particular, the Theory of Work Adjustment (TWA) (Dawis and Lofquist, 1984) to understand and categorize the reasons for leaving the engineering field. According to the TWA, occupations have different "reinforcer patterns," reflected in six occupational values, and a mismatch between the reinforcers provided by the work environment and individuals' needs may trigger departure from the environment. Given the paucity of literature in this area, we posed research questions to explore the reinforcer pattern of values implicated in women's decisions to leave the engineering field. We used qualitative analyses to understand, categorize, and code the 1,863 statements that offered a glimpse into the myriad reasons that women offered in describing their decisions to leave the engineering profession. Our results revealed the top three sets of reasons underlying women's decision to leave the jobs and engineering field were related to: first, poor and/or inequitable compensation, poor working conditions, inflexible and demanding work environment that made work-family balance difficult; second, unmet achievement needs that reflected a dissatisfaction with effective utilization of their math and science skills, and third, unmet needs with regard to lack of recognition

  2. BiI<sub>3sub> Crystals for High Energy Resolution Gamma-Ray Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Nino, Juan C. [Univ. of Florida, Gainesville, FL (United States); Baciak, James [Univ. of Florida, Gainesville, FL (United States); Johns, Paul [Univ. of Florida, Gainesville, FL (United States); Sulekar, Soumitra [Univ. of Florida, Gainesville, FL (United States); Totten, James [Univ. of Florida, Gainesville, FL (United States); Nimmagadda, Jyothir [Univ. of Florida, Gainesville, FL (United States)

    2017-04-12

    BiI<sub>3sub> had been investigated for its unique properties as a layered compound semiconductor for many decades. However, despite the exceptional atomic, physical, and electronic properties of this material, good resolution gamma ray spectra had never been reported for BiI<sub>3sub>. The shortcomings that previously prevented BiI<sub>3sub> from reaching success as a gamma ray sensor were, through this project, identified and suppressed to unlock the performance of this promising compound. Included in this work were studies on a number of methods which have, for the first time, enabled BiI<sub>3sub> to exhibit spectral performance rivaling many other candidate semiconductors for room temperature gamma ray sensors. New approaches to crystal growth were explored that allow BiI<sub>3sub> spectrometers to be fabricated with up to 2.2% spectral resolution at 662 keV. Fundamental studies on trap states, dopant incorporation, and polarization were performed to enhance performance of this compound. Additionally, advanced detection techniques were applied to display the capabilities of high quality BiI<sub>3sub> spectrometers. Overall, through this work, BiI<sub>3sub> has been revealed as a potentially transformative material for nuclear security and radiation detection sciences.

  3. Growth mechanisms for spherical mixed hydroxide agglomerates prepared by co-precipitation method: A case of Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3}(OH){sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yue [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Xu, Shengming, E-mail: smxu@stinghua.edu.cn [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Xie, Ming [The State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Precious Metals, Kunming 650106 (China); He, Yinghe, E-mail: yinghe.he@jcu.edu.au [School of Engineering and Physical Sciences, James Cook University, Douglas, Queensland 4811 (Australia); Huang, Guoyong [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Yang, Youcai [The State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Precious Metals, Kunming 650106 (China)

    2015-01-15

    Highlights: • Anisotropic growth of Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3}(OH){sub 2} along the [0 0 1] direction was revealed. • DFT calculation results show crystal surface energies of (0 0 1) plane is highest. • A new model was proposed to explain the formation of spherical agglomerates. - Abstract: Spherical Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3}(OH){sub 2} agglomerates were synthesized by the co-precipitation method in the presence of ammonia. The results show that the growth mechanism of spherical agglomerates follows three-stages, i.e. nucleation and anisotropic growth of single crystals; agglomeration of polycrystalline crystallites agglomerated by single crystal grains as primary particles to form embryonic agglomerates; formation, growth and consolidation of spherical agglomerates or particles by agglomeration of embryonic agglomerates, continued growth of individual crystals in the agglomerates and further attachment of primary particles. The first two stages are very fast while the last stage takes almost the entire process to complete. The main reason for the anisotropic growth of Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3}(OH){sub 2} crystal is that crystal surface energy of E{sub (001)}, E{sub (100)}, E{sub (101)} and E{sub (102)} is different with E{sub (001)} being the highest. The morphology of the final spherical agglomerates is explained by partial re-crystallization of contacting primary particles. The growth process of spherical agglomerates was examined by X-ray diffraction, scanning electron microscope, transmission electron microscope and calculation of crystal surface energy using density function theory.

  4. Giant electrical conductivity enhancement in BaO-V{sub 2}O{sub 5}-Bi{sub 2}O{sub 3} glass by nanocrystallization

    Energy Technology Data Exchange (ETDEWEB)

    El-Desoky, M.M., E-mail: mmdesoky@gmail.com [Department of Physics, Faculty of Education, Suez Canal University, Al-Arish (Egypt)

    2010-02-15

    The effects of the annealing of 20BaO-30V{sub 2}O{sub 5}-50Bi{sub 2}O{sub 3} glass on the structural and electrical properties were studied by scanning electron micrographs (SEM), X-ray diffraction (XRD), differential scanning calorimeter (DSC) density (d) and dc conductivity ({sigma}). The XRD and SEM observations have shown that the sample under study undergoes structural changes: from amorphous at the beginning, to partly crystalline after nanocrystallization at crystallization temperature (T{sub c}) for 1 h and to colossal crystallization after the annealing at the same temperature for 24 h. The average size of these grains after nanocrystallization at T{sub c} for 1 h was estimated to be about 25-35 nm. However, the glass heat treated at T{sub c} = 580 deg. C for 24 h the microstructure changes considerably. The nanomaterials obtained by nanocrystallization at T{sub c} for 1 h exhibit giant improvement of electrical conductivity up to four order of magnitude and better thermal stability than the as-received glass. The major role in the conductivity enhancement of this nanomaterial is played by the developed interfacial regions 'conduction tissue' between crystalline and amorphous phases, in which the concentration of V{sup 4+}-V{sup 5+} pairs responsible for electron hopping is higher than inside the glassy matrix. The annealing at T{sub c} for 24 h leads to decrease of the electronic conductivity. This phenomena lead to disappearance of the abovementioned 'conduction tissue' for electrons and substantial reduction of electronic conductivity. The high temperature (above {theta}/2) dependence of conductivity could be qualitatively explained by the small polaron hopping (SPH) model. The physical parameters obtained from the best fits of this model are found reasonable and consistent with the glass compositions.

  5. Correlation, necessity, and sufficiency: Common errors in the scientific reasoning of undergraduate students for interpreting experiments.

    Science.gov (United States)

    Coleman, Aaron B; Lam, Diane P; Soowal, Lara N

    2015-01-01

    Gaining an understanding of how science works is central to an undergraduate education in biology and biochemistry. The reasoning required to design or interpret experiments that ask specific questions does not come naturally, and is an essential part of the science process skills that must be learned for an understanding of how scientists conduct research. Gaps in these reasoning skills make it difficult for students to become proficient in reading primary scientific literature. In this study, we assessed the ability of students in an upper-division biochemistry laboratory class to use the concepts of correlation, necessity, and sufficiency in interpreting experiments presented in a format and context that is similar to what they would encounter when reading a journal article. The students were assessed before and after completion of a laboratory module where necessary vs. sufficient reasoning was used to design and interpret experiments. The assessment identified two types of errors that were commonly committed by students when interpreting experimental data. When presented with an experiment that only establishes a correlation between a potential intermediate and a known effect, students frequently interpreted the intermediate as being sufficient (causative) for the effect. Also, when presented with an experiment that tests only necessity for an intermediate, they frequently made unsupported conclusions about sufficiency, and vice versa. Completion of the laboratory module and instruction in necessary vs. sufficient reasoning showed some promise for addressing these common errors. © 2015 The International Union of Biochemistry and Molecular Biology.

  6. Surface modification of η-Al{sub 2}O{sub 3} by SiO{sub 2} impregnation to enhance methanol dehydration activity

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Ho Yong; Park, Jin Won [Dept. of Chemistry and Biomolecular Engineering, Yonsei University, Seoul (Korea, Republic of); Jung, Heon; Jung, Kwang Deog [Clean Energy Research Center, Korea Institute of Science and Technology, Seoul (Korea, Republic of)

    2017-03-15

    Silica impregnated η-Al{sub 2}O{sub 3} catalysts (Si(number)Al) were prepared for methanol dehydration, with the number indicating the Si wt % added to η-Al{sub 2}O{sub 3}. The Si(0.25)Al and Si(0.50)Al catalysts with the greatest number of acid sites had the highest methanol dehydration activities among the prepared catalysts. Si addition up to 0.5 wt % increased the number of the acid sites, which was slightly decreased by further Si addition. The number of weak acid sites correlated well with the catalytic activity for methanol dehydration, but was not enough to explain the higher activity of the catalysts containing silica compared with η-Al{sub 2}O{sub 3}. The acid sites of the Si(1.0)Al catalyst were less than those of the η-Al{sub 2}O{sub 3} catalyst but the two had similar activity. Si addition primarily increased the Lewis acid sites, although it generated a few new BrO. With Strokensted acid sites and chemical hydrogen bonded sites. Nonetheless, it was apparent that the increase of Lewis acid sites was the main reason for the enhancement of η-Al{sub 2}O{sub 3} activity by SiO{sub 2} addition. On the other hand, the new BrO. With Strokensted and Lewis acid sites and the chemical hydrogen bonded sites created by Si addition should not be neglected.

  7. Relational Reasoning in Word and in Figure

    Science.gov (United States)

    Alexander, Patricia A.; Singer, Lauren M.; Jablansky, Sophie; Hattan, Courtney

    2016-01-01

    This study investigated the relational reasoning capabilities of older adolescents and young adults when the focal assessment was a verbal and more schooled measure than 1 that was figural and more novel in its configuration. To achieve this end, the verbal test of relational reasoning (vTORR) was constructed to parallel the test of relational…

  8. Reason and ethos: Consequences of their separation and necessity of their unity

    Directory of Open Access Journals (Sweden)

    Marković Mihailo

    2003-01-01

    Full Text Available Although the concept of "reason" acquired a precise meaning and clearly defined field of validity only in Kant's critical philosophy, the term has a long genesis in European intellectual history. The roots of the concept lie in the Greek concept of the logos and may be reduced to six basic meanings. The earliest Greek thinkers used the word logos to denote the logical structure of the human thought and the rational structure of the world. Anaxagoras considered the all-embracing spiritual principle of the nous the source of overall rationality. In the philosophy of the Stoa the term - logos spermaticos is the active principle acting on passive matter in order to create the world. For the Stoics, the concept of logos is the fundamental principle of entire morality. In Christian theology, the God is logos, Holy Spirit - pneuma the soul. In modern philosophy the basic meanings of the Greek logos were taken over by Latin terms "intellectus" and "ratio". These concepts chart quite clearly two basic lines of European thought, one characterized by immediate and the other by mediated discursive understanding of the truth. Kant was the first in the history of philosophy to introduce the essential distinction between understanding and reason (Verstand and Vernunft. According to this distinction, understanding is analytical and abstract, while reason is the source of apriori principles connecting and grounding the whole of our knowledge and volition. Therefore Kant distinguishes theoretical from practical reason. Though practical reason applies the concepts and principles of theoretical reason, it has priority over the latter because it bestows practical reality also on what is theoretically unknowable (freedom, God, immortality of the soul. The primacy of practical reason was especially emphasized by Fichte in his Doctrine of Science. Reason is for him a purely purposeful activity. The idea of reason attains full articulation in Hegel's philosophy of the

  9. Estimation of Post-Test Probabilities by Residents: Bayesian Reasoning versus Heuristics?

    Science.gov (United States)

    Hall, Stacey; Phang, Sen Han; Schaefer, Jeffrey P.; Ghali, William; Wright, Bruce; McLaughlin, Kevin

    2014-01-01

    Although the process of diagnosing invariably begins with a heuristic, we encourage our learners to support their diagnoses by analytical cognitive processes, such as Bayesian reasoning, in an attempt to mitigate the effects of heuristics on diagnosing. There are, however, limited data on the use ± impact of Bayesian reasoning on the accuracy of…

  10. CO{sub 2} regulation. The case of Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Tinggaard Svendsen, G. [Faculty of Business Administration, Dept. of Economics (Denmark)

    1996-12-31

    For economic, political, and administrative reasons, a mixed design of permit market, bubble and tax is preferable for CO{sub 2} regulation in Denmark. A CO{sub 2} market should be introduced for the private manufacturing sector in Denmark and an administratively set CO{sub 2} bubble should be introduced for the public electricity sector. Permits are then to be devaluated in year 2005 by 20%. A CO{sub 2} tax should be correctly set at a US dollar 50 level in year 2005 for households, transportation sector and private firms not participating in the CO{sub 2} market. (au) 49 p.

  11. Assessing model-based reasoning using evidence-centered design a suite of research-based design patterns

    CERN Document Server

    Mislevy, Robert J; Riconscente, Michelle; Wise Rutstein, Daisy; Ziker, Cindy

    2017-01-01

    This Springer Brief provides theory, practical guidance, and support tools to help designers create complex, valid assessment tasks for hard-to-measure, yet crucial, science education standards. Understanding, exploring, and interacting with the world through models characterizes science in all its branches and at all levels of education. Model-based reasoning is central to science education and thus science assessment. Current interest in developing and using models has increased with the release of the Next Generation Science Standards, which identified this as one of the eight practices of science and engineering. However, the interactive, complex, and often technology-based tasks that are needed to assess model-based reasoning in its fullest forms are difficult to develop. Building on research in assessment, science education, and learning science, this Brief describes a suite of design patterns that can help assessment designers, researchers, and teachers create tasks for assessing aspects of model-based...

  12. Hot-forging of YBa/sub 2/Cu/sub 3/O/sub y/ powder

    Energy Technology Data Exchange (ETDEWEB)

    Nishida, Toshihiko; Shiono, Takeshi; Fujioka, Hideaki; Nishikawa, Tomozo

    1988-07-25

    Ceramic superconductor of YBa/sub 2/Cu/sub 3/O/sub y/ with a unidirectionally oriented (00l) face of crystal was prepared by sintering for decreasing the intergranular effect on the conducting channel. It was expected that the current density of the superconductor would be high. The effect of the short compression molding process or the particle orientation of YBa/sub 2/Cu/sub 3/O/sub y/ was examined by the high-temperature uniaxial compression test. Powder of rhombic YBa/sub 2/Cu/sub 3/O/sub y/ ceramic alone was put in a metallic mold and uniaxially compressed at 950/sup 0/C for approximately eight minutes. The sectional areas of the material sintered in a disk shape in the mold perpendicular and parallel to the compression axis were measured by X-ray refractometry. The result indicates that the (00l) face of crystal is remarkably oriented to the direction perpendicular to the compression axis. (4 figs, 1 tab, 2 photos, 9 refs)

  13. Learning Science Through Visualization

    Science.gov (United States)

    Chaudhury, S. Raj

    2005-01-01

    In the context of an introductory physical science course for non-science majors, I have been trying to understand how scientific visualizations of natural phenomena can constructively impact student learning. I have also necessarily been concerned with the instructional and assessment approaches that need to be considered when focusing on learning science through visually rich information sources. The overall project can be broken down into three distinct segments : (i) comparing students' abilities to demonstrate proportional reasoning competency on visual and verbal tasks (ii) decoding and deconstructing visualizations of an object falling under gravity (iii) the role of directed instruction to elicit alternate, valid scientific visualizations of the structure of the solar system. Evidence of student learning was collected in multiple forms for this project - quantitative analysis of student performance on written, graded assessments (tests and quizzes); qualitative analysis of videos of student 'think aloud' sessions. The results indicate that there are significant barriers for non-science majors to succeed in mastering the content of science courses, but with informed approaches to instruction and assessment, these barriers can be overcome.

  14. What Kills Science in School?: Lessons from Pre-Service Teachers' Responses to Urban children's Science Inquiries.

    Science.gov (United States)

    Matusov, Eugene

    2018-06-01

    This opportunistic case-study highlights striking differences in 6 urban children's and 12 preservice suburban middle-class teachers' perception of science and discuss consequences of science education and beyond. I found that all of the interviewed urban children demonstrated scientific inquiries and interests outside of the school science education that can be characterized by diverse simultaneous discourses from diverse practices, i.e., "heterodiscoursia" (Matusov in Culture & Psychology, 17(1), 99-119, 2011b), despite their diverse, positive and negative, attitudes toward school science. In contrast to the urban children's mixed attitudes to science, the preservice teachers view science negatively. They could not see science inquiries in the videotaped interviews of the urban children. There seemed to be many reasons for that. One of the possible reasons for that was that the preservice teachers tried to purify the science practice. Another reason was that they did not see a necessity to be interested and engaged in the curriculum that they are going to teach in future. The pedagogical consequences and remedies are discussed.

  15. The Development of Analogical Reasoning Processes.

    Science.gov (United States)

    Sternberg, Robert J.; Rifkin, Bathsheva

    1979-01-01

    Two experiments were conducted to test the generalizability to children of a theory of analogical reasoning processes, originally proposed for adults, and to examine the development of analogical reasoning processes in terms of five proposed sources of cognitive development. (MP)

  16. Common Variance Among Three Measures of Nonverbal Cognitive Ability: WISC-R Performance Scale, WJPB-TCA Reasoning Cluster, and Halstead Category Test.

    Science.gov (United States)

    Telzrow, Cathy F.; Harr, Gale A.

    1987-01-01

    Examined the relationships among two psychometric measures of nonverbal cognitive ability - The Wechsler Intelligence Scale for Children-Revised (WISC-R) and the Woodcock-Johnson Psychoeducational Battery-Tests of Cognitive Ability (WJPB-TCA) and a neuropsychological test of abstract reasoning and concept formation (Halstead Category Test) in 25…

  17. From Ba{sub 3}Ta{sub 5}O{sub 14}N to LaBa{sub 2}Ta{sub 5}O{sub 13}N{sub 2}: Decreasing the optical band gap of a photocatalyst

    Energy Technology Data Exchange (ETDEWEB)

    Anke, B. [Institut für Chemie, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin (Germany); Bredow, T. [Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie, Universität Bonn, Beringstr. 4, 53115 Bonn (Germany); Pilarski, M.; Wark, M. [Institut für Chemie, Carl von Ossietzky Universität Oldenburg, Carl-von-Ossietzky-Str. 9-11, 26129 Oldenburg (Germany); Lerch, M., E-mail: martin.lerch@tu-berlin.de [Institut für Chemie, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin (Germany)

    2017-02-15

    Yellow LaBa{sub 2}Ta{sub 5}O{sub 13}N{sub 2} was successfully synthesized as phase-pure material crystallizing isostructurally to previously reported Ba{sub 3}Ta{sub 5}O{sub 14}N and mixed-valence Ba{sub 3}Ta{sup V}{sub 4}Ta{sup IV}O{sub 15}. The electronic structure of LaBa{sub 2}Ta{sub 5}O{sub 13}N{sub 2} was studied theoretically with the range-separated hybrid method HSE06. The most stable structure was obtained when lanthanum was placed on 2a and nitrogen on 4h sites confirming Pauling's second rule. By incorporating nitrogen, the measured band gap decreases from ∼3.8 eV for the oxide via 2.74 eV for Ba{sub 3}Ta{sub 5}O{sub 14}N to 2.63 eV for the new oxide nitride, giving rise to an absorption band well in the visible-light region. Calculated fundamental band gaps confirm the experimental trend. The atom-projected density of states has large contributions from N2p orbitals close to the valence band edge. These are responsible for the observed band gap reduction. Photocatalytic hydrogen formation was investigated and compared with that of Ba{sub 3}Ta{sub 5}O{sub 14}N revealing significantly higher activity for LaBa{sub 2}Ta{sub 5}O{sub 13}N{sub 2} under UV-light. - Graphical abstract: X-ray powder diffraction pattern of LaBa{sub 2}Ta{sub 5}O{sub 13}N{sub 2} with the results of the Rietveld refinements. Inset: Unit cell of LaBa{sub 2}Ta{sub 5}O{sub 13}N{sub 2} and polyhedral representation of the crystal structure. - Highlights: • Synthesis of a new oxide nitride LaBa{sub 2}Ta{sub 5}O{sub 13}N{sub 2}. • Refinement of the crystal structure. • Quantum chemical calculations provided band gap close to the measured value. • New phase shows a higher photocatalytic H{sub 2} evolution rate compared to prior tested Ba{sub 3}Ta{sub 5}O{sub 14}N.

  18. Application of Ce{sub x}Zr{sub 1-x}O{sub 2} catalysts for the synthesis of diethyl carbonate from ethanol and carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Prymak, I.; Kalevaru, V.N.; Kollmorgen, P.; Wohlrab, S. [Leibniz-Institut fuer Katalyse e.V. an der Universitaet Rostock (Germany); Martin, A.

    2013-11-01

    The direct synthesis of diethyl carbonate (DEC) from ethanol and CO{sub 2} is indeed an attractive approach from both academic and commercial points of view. In the present study, we report on the synthesis, characterization and catalytic evaluation of Ce-Zr-O solids with varying Ce/Zr ratios. The catalysts were prepared by citrate complexation method, and characterized by various techniques such as N{sub 2} adsorption (BET-SA), XRD, H{sub 2}-TPR, NH{sub 3}-TPD etc. The catalytic performance of these catalysts was evaluated towards the synthesis of DEC from ethanol and CO{sub 2} under suitable reaction conditions. According to thermodynamic data, the reaction is favorable at low reaction temperatures and high reaction pressures. Thus, the catalytic experiments were carried out in a continuous mode using a plug-flow reactor that was operated up to 200 bar and ca. 200 C. The effect of the reaction temperature (30-180 C) and pressure (80-180 bar) on the yield of DEC was investigated. Among various catalysts tested, Ce-Zr-O catalyst with 80 mol% Ce content has exhibited a relatively better performance compared to all other Ce-Zr-O catalysts. DEC yield increased with increasing reaction temperature up to 140 C. The highest yield of DEC obtained from the best case was 0.7 % at 140 C and at 140 bars. Further increase in temperature to 180 C caused a decrease in the DEC formation due to thermodynamic reasons as mentioned above. The ceria proportion has shown a considerable influence on the BET surface areas and thereby catalytic activity as well. The results revealed that the redox properties as well as acidity characteristics of the solids are strongly influenced by the content of Ce in the catalysts, which in turn showed a clear impact on the catalytic performance. (orig.)

  19. Integrated Data Collection Analysis (IDCA) program--KClO<sub>4sub>/Dodecane Mixture

    Energy Technology Data Exchange (ETDEWEB)

    Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Sorensen, Daniel N. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Shelley, Timothy J. [Air Force Research Lab. (AFRL), Tyndall AFB, FL (United States); Reyes, Jose A. [Applied Research Associates, Tyndall AFB, FL (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2012-05-11

    The Integrated Data Collection Analysis (IDCA) program is conducting a proficiency study for Small- Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the results for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis of a mixture of KClO<sub>4sub> and dodecane—KClO<sub>4sub>/dodecane mixture. This material was selected because of the challenge of performing SSST testing of a mixture of solid and liquid materials. The mixture was found to: 1) be less sensitive to impact than RDX, and PETN, 2) less sensitive to friction than RDX and PETN, and 3) less sensitive to spark than RDX and PETN. The thermal analysis showed little or no exothermic features suggesting that the dodecane volatilized at low temperatures. A prominent endothermic feature was observed and assigned to a phase transition of KClO<sub>4sub>. This effort, funded by the Department of Homeland Security (DHS), ultimately will put the issues of safe handling of these materials in perspective with standard military explosives. The study is adding SSST testing results for a broad suite of different HMEs to the literature. Ultimately the study has the potential to suggest new guidelines and methods and possibly establish the SSST testing accuracies needed to develop safe handling practices for HMEs. Each participating testing laboratory uses identical test materials and preparation methods wherever possible. Note, however, the test procedures differ among the laboratories. The results are compared among the laboratories and then compared to historical data from various sources. The testing performers involved for the KClO<sub>4sub>/dodecane mixture are Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Indian Head Division, Naval Surface Warfare Center, (NSWC IHD), and Air Force Research Laboratory (AFRL/RXQL). These tests are conducted as a proficiency study in order to establish some

  20. Varieties of noise: analogical reasoning in synthetic biology.

    Science.gov (United States)

    Knuuttila, Tarja; Loettgers, Andrea

    2014-12-01

    The picture of synthetic biology as a kind of engineering science has largely created the public understanding of this novel field, covering both its promises and risks. In this paper, we will argue that the actual situation is more nuanced and complex. Synthetic biology is a highly interdisciplinary field of research located at the interface of physics, chemistry, biology, and computational science. All of these fields provide concepts, metaphors, mathematical tools, and models, which are typically utilized by synthetic biologists by drawing analogies between the different fields of inquiry. We will study analogical reasoning in synthetic biology through the emergence of the functional meaning of noise, which marks an important shift in how engineering concepts are employed in this field. The notion of noise serves also to highlight the differences between the two branches of synthetic biology: the basic science-oriented branch and the engineering-oriented branch, which differ from each other in the way they draw analogies to various other fields of study. Moreover, we show that fixing the mapping between a source domain and the target domain seems not to be the goal of analogical reasoning in actual scientific practice.

  1. Comparative study of perovskite Pr{sub (1-x)}Ca{sub x}CoO{sub 3} e Gd{sub (1-x)}Ca{sub x}CoO{sub 3} (x=0,2) synthesized by gelatin modified route for application in automotive catalysis; Estudo comparativo das perovsquitas Pr{sub (1-x)}Ca{sub x}CoO{sub 3} e Gd{sub (1-x)}Ca{sub x}CoO{sub 3} (x=0,2) sintetizadas pela rota modificada gelatina para aplicacao em catalise automotiva

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, E.M. de; Medeiros, M.R.A.; Paiva, A.K.O.; Borges, F.M.M., E-mail: eduardamedeirosdearaujo@gmail.com [Universidade Federal do Rio Grande do Norte (UFRN), RN (Brazil); Ruiz, J.A.C. [Centro de Tecnologia do Gas e Energias Renovaveis (CTGAS-ER), RN (Brazil)

    2016-07-01

    Increased air pollution intensified the search for materials that could convert pollutant gases into less harmful substances. Thus, mixed oxides with perovskite structure began to be developed for presenting important features for the automotive catalysis. In this study has been compared the chemical composition of the materials with Pr{sub (1-x)}Ca{sub x}CoO{sub 3} and Gd{sub (1-x)}Ca{sub x}CoO{sub 3} (x = 0.2) synthesized by the method gelatine. The samples were characterized by techniques: Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-Ray Diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray fluorescence (XRF) and subjected to the catalytic test in methane combustion reaction. The evaluation of the catalytic activity showed that gadolinium catalyst is more efficient compared with the praseodymium catalyst, although they have similar maximum conversion of methane at high temperature, during the catalytic test the material with gadolinium showed higher catalytic activity and stability. (author)

  2. Magnetoresistance and spin frustration at low temperature in LaMn sub 1 sub - sub x Ni sub x O sub 3 sub + subdelta (0 <= x <= 0.1)

    CERN Document Server

    Yamamoto, A

    2003-01-01

    This paper investigates the relation between the temperature dependence of magnetoresistance (MR) and spin frustration in LaMnO sub 3 sub + subdelta when Ni is doped into the Mn site. The specimens experience magnetic frustration introduced by the competition between antiferromagnetic (AFM) and ferromagnetic (FM) interactions. According to the temperature dependence of magnetization after cooling the specimen in zero field and non-zero field, Ni-doped specimens behave like cluster glasses. This magnetic frustration at the low temperature is believed to result from the disordered spin structure between AFM and FM phases in these specimens. When the structural symmetry in the specimen is higher, the FM arrangement increases by double the exchange interaction. However, MR decreases in the same temperature region for the same reason. We suggest that the temperature dependence of MR below the Curie temperature in the Ni-doped specimen is controlled by the change of magnetization that occurs with structural change.

  3. Formation mechanism of precipitate T{sub 1} in AlCuLi alloys

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Z. [Center for High-Resolution Electron Microscopy, College of Materials Science and Engineering, Hunan University, Changsha, Hunan 410082 (China); Liu, J.Z., E-mail: jzliu123@hnu.edu.cn [Center for High-Resolution Electron Microscopy, College of Materials Science and Engineering, Hunan University, Changsha, Hunan 410082 (China); Hunan Province Key Laboratory for Spray Deposition Technology and Application, Hunan University, Changsha, Hunan 410082 (China); Chen, J.H., E-mail: jhchen123@hnu.edu.cn [Center for High-Resolution Electron Microscopy, College of Materials Science and Engineering, Hunan University, Changsha, Hunan 410082 (China); Hunan Province Key Laboratory for Spray Deposition Technology and Application, Hunan University, Changsha, Hunan 410082 (China); Duan, S.Y.; Liu, Z.R.; Ming, W.Q.; Wu, C.L. [Center for High-Resolution Electron Microscopy, College of Materials Science and Engineering, Hunan University, Changsha, Hunan 410082 (China)

    2015-03-05

    Highlights: • We found that T{sub 1}-precipitates nucleate directly from GP{sub T1} zones. • We found that T{sub 1}-precipitates grow thicker in two possible paths. • We determined the structure of GP{sub T1} zones by advanced atomic imaging techniques. • We suggested a possible structural evolution from GP{sub T1} zones to precipitate T{sub 1}. • The suggested structural evolution was proved to be energetically reasonable. - Abstract: The formation mechanism of the plate-like strengthening T{sub 1}-phase in an Al–4.15Cu–1.15Li (wt.%) alloy has been revealed by means of advanced imaging techniques and the first-principle calculations. It is shown that T{sub 1}-precipitates nucleate directly from their own GP{sub T1} zones and grow thicker in two possible paths. One is regular by repeating T{sub 1}-cells, and the other is abnormal via T{sub 1}-variants. Structural model of GP{sub T1} zones has been suggested, and refined by image simulation. A possible structural evolution from GP{sub T1} zones to precipitate T{sub 1} at atomic level is suggested and proved to be energetically reasonable.

  4. Enhanced visible light photocatalytic H{sub 2} evolution of metal-free g-C{sub 3}N{sub 4}/SiC heterostructured photocatalysts

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Biao, E-mail: wangbiao@fjirsm.ac.cn [Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); University of the Chinese Academy of Sciences, Beijing 100049 (China); Zhang, Jingtao, E-mail: zhangjtao@mail.sysu.edu.cn [State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510006 (China); Huang, Feng, E-mail: huangfeng@mail.sysu.edu.cn [Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510006 (China)

    2017-01-01

    Highlights: • Novel g-C{sub 3}N{sub 4}/SiC composite was prepared by synthesizing g-C{sub 3}N{sub 4} on the surface of SiC. • g-C{sub 3}N{sub 4}/SiC composites exhibit much higher H{sub 2} production activity than pure g-C{sub 3}N{sub 4}. • The g-C{sub 3}N{sub 4}/SiC heterojunction mainly accounts for improved photocatalytic activity. - Abstract: g-C{sub 3}N{sub 4} has been attracting much attention for application in visible light photocatalytic water splitting due to its suitable band structure, and high thermal and chemical stability. However, the rapid recombination of photogenerated carriers has inhibited its wide use. For this reason, novel g-C{sub 3}N{sub 4}/SiC composites were prepared via in situ synthesis of g-C{sub 3}N{sub 4} on the surface of SiC, with which g-C{sub 3}N{sub 4} shows tight interaction (chemical bonding). The g-C{sub 3}N{sub 4}/SiC composites exhibit high stability in H{sub 2} production under irradiation with visible light (λ ≥ 420 nm), demonstrating a maximum of 182 μmol g{sup −1} h{sup −1}, being 3.4 times higher than that of pure g-C{sub 3}N{sub 4}. The enhanced photocatalytic H{sub 2} production ability for g-C{sub 3}N{sub 4}/SiC photocatalysts is primarily ascribed to the combined effects of enhanced separation of photogenerated carriers through efficient migration of electron and enlarged surface areas, in addition to the possible contributions of increased hydrophilicity of SiC and polymerization degree of g-C{sub 3}N{sub 4}. This study may provide new insights into the development of g-C{sub 3}N{sub 4}-based composites as stable and efficient photocatalysts for H{sub 2} production from water splitting.

  5. Study on the thyroid function of thoroughbred females in varying stages of pregnancy using 'in vitro' tests /sup 125/I-T/sub 3/ and /sup 125/I-T/sub 4/

    Energy Technology Data Exchange (ETDEWEB)

    de Martin, B W [Sao Paulo Univ. (Brazil). Faculdade de Medicina Veterinaria e Zootecnia

    1975-01-01

    A study is made on the thyroid function of thoroughbred female equines, aged between five through twelve years, in varying stages of pregnancy, using 'in vitro' tests /sup 125/I.T/sub 3/ and /sup 125/I-T/sub 4/.

  6. Overview of the testing activities on ITER sub-scale pre-compression rings

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, Paolo, E-mail: paolo.rossi@enea.it [Associazione EURATOM-ENEA sulla Fusione, C.R. Frascati, C.P. 65, 00044 Frascati, Rome (Italy); Capobianchi, Mario; Crescenzi, Fabio; Massimi, Alberto; Mugnaini, Giampiero; Pizzuto, Aldo [Associazione EURATOM-ENEA sulla Fusione, C.R. Frascati, C.P. 65, 00044 Frascati, Rome (Italy); Knaster, Juan [ITER Organisation, Route de Vinon sur Verdon, 13115, St. Paul lez Durance (France); Rajainmaki, Hannu [FUSION FOR ENERGY, Josep Pla no. 2, Torres Diagonal Litoral Edificio B3, 08019 Barcelona (Spain)

    2012-08-15

    Highlights: Black-Right-Pointing-Pointer ENEA developed a high strength glass fiber-epoxy composite for ITER pre-compression rings. Black-Right-Pointing-Pointer High UTS values were obtained at RT on linear specimens (2200 MPa) and on scaled ring mock-ups (1550 MPa). Black-Right-Pointing-Pointer Creep tests showed very low creep strain and creep rates. Black-Right-Pointing-Pointer Long term tests showed no significant stress relaxation on the ring mock-ups. - Abstract: After a first R and D and testing activity to develop and characterize by tensile and creep tests a high strength glass fiber-epoxy composite as reference material for the manufacture of ITER pre-compression rings, ENEA designed and manufactured a dedicated testing facility and different sub-scale composite ring mock-ups in order to characterize their mechanical properties. The paper reports the results of the overall testing activities performed during the last years on a total number of eleven sub-scale pre-compression ring mock-ups manufactured by winding S2 glass fibers on a diameter of 1 m (1/5 of the full scale) both by vacuum pressure epoxy impregnation (VPI) and filament wet winding techniques (WW). The first three rings were manufactured by ENEA Frascati thanks to a particular VPI technique; one of them was used as base composite material to manufacture different sets of specimens for shear, compression and non destructive tests (NDT). Then, five other mock-ups were manufactured following ENEA VPI process and three using WW technique by two different industrial companies. The rings were tested in ENEA Frascati in a dedicated hydraulic testing machine consisting of 18 radial actuators working in position control with a total load capability of 1000 tons. The complete testing campaign consisted of six ultimate tensile strength (UTS) tests and four stress relaxation (SR) tests. The tests demonstrated that the composite (S2 glass-epoxy) is a valid and viable solution for the ITER pre

  7. Art-science, beauty-reason and holography

    International Nuclear Information System (INIS)

    Jeong, T H

    2013-01-01

    Display holography holds a distinction that makes it appealing to a wide audience. It can be appreciated at a deep level by people of all ages and in all fields of endeavor. It provides a unique opportunity for us to gather in an intimate location to learn, enjoy, and enlighten one another. This paper offers demonstrations to explore the relationships between art and science, esthetics and mathematics, and the dualities that exist in nature. On the practical level, a visual model for deep understanding of holography and a proposal for 'making holograms that sell' will be presented. In writing this article, the author acknowledges the fact that for this symposium, a Proceeding will be published as well as a set of audio-visual recordings. With that in mind, this article represents largely the printable contents, leaving the audio-visual part as 'performance' to be electronically recorded.

  8. SPE5 Sub-Scale Test Series Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Vandersall, Kevin S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reeves, Robert V. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); DeHaven, Martin R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Strickland, Shawn L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-01-14

    A series of 2 SPE5 sub-scale tests were performed to experimentally confirm that a booster system designed and evaluated in prior tests would properly initiate the PBXN-110 case charge fill. To conduct the experiments, a canister was designed to contain the nominally 50 mm diameter booster tube with an outer fill of approximately 150 mm diameter by 150 mm in length. The canisters were filled with PBXN-110 at NAWS-China Lake and shipped back to LLNL for testing in the High Explosives Applications Facility (HEAF). Piezoelectric crystal pins were placed on the outside of the booster tube before filling, and a series of piezoelectric crystal pins along with Photonic Doppler Velocimetry (PDV) probes were placed on the outer surface of the canister to measure the relative timing and magnitude of the detonation. The 2 piezoelectric crystal pins integral to the booster design were also utilized along with a series of either piezoelectric crystal pins or piezoelectric polymer pads on the top of the canister or outside case that utilized direct contact, gaps, or different thicknesses of RTV cushions to obtain time of arrival data to evaluate the response in preparation for the large-scale SPE5 test. To further quantify the margin of the booster operation, the 1st test (SPE5SS1) was functioned with both detonators and the 2nd test (SPE5SS2) was functioned with only 1 detonator. A full detonation of the material was observed in both experiments as observed by the pin timing and PDV signals. The piezoelectric pads were found to provide a greater measured signal magnitude during the testing with an RTV layer present, and the improved response is due to the larger measurement surface area of the pad. This report will detail the experiment design, canister assembly for filling, final assembly, experiment firing, presentation of the diagnostic results, and a discussion of the results.

  9. Sex Differences in Fluid Reasoning: Manifest and Latent Estimates from the Cognitive Abilities Test

    Directory of Open Access Journals (Sweden)

    Joni M. Lakin

    2014-06-01

    Full Text Available The size and nature of sex differences in cognitive ability continues to be a source of controversy. Conflicting findings result from the selection of measures, samples, and methods used to estimate sex differences. Existing sex differences work on the Cognitive Abilities Test (CogAT has analyzed manifest variables, leaving open questions about sex differences in latent narrow cognitive abilities and the underlying broad ability of fluid reasoning (Gf. This study attempted to address these questions. A confirmatory bifactor model was used to estimate Gf and three residual narrow ability factors (verbal, quantitative, and figural. We found that latent mean differences were larger than manifest estimates for all three narrow abilities. However, mean differences in Gf were trivial, consistent with previous research. In estimating group variances, the Gf factor showed substantially greater male variability (around 20% greater. The narrow abilities varied: verbal reasoning showed small variability differences while quantitative and figural showed substantial differences in variance (up to 60% greater. These results add precision and nuance to the study of the variability and masking hypothesis.

  10. The Impact of Data-Based Science Instruction on Standardized Test Performance

    Science.gov (United States)

    Herrington, Tia W.

    Increased teacher accountability efforts have resulted in the use of data to improve student achievement. This study addressed teachers' inconsistent use of data-driven instruction in middle school science. Evidence of the impact of data-based instruction on student achievement and school and district practices has been well documented by researchers. In science, less information has been available on teachers' use of data for classroom instruction. Drawing on data-driven decision making theory, the purpose of this study was to examine whether data-based instruction impacted performance on the science Criterion Referenced Competency Test (CRCT) and to explore the factors that impeded its use by a purposeful sample of 12 science teachers at a data-driven school. The research questions addressed in this study included understanding: (a) the association between student performance on the science portion of the CRCT and data-driven instruction professional development, (b) middle school science teachers' perception of the usefulness of data, and (c) the factors that hindered the use of data for science instruction. This study employed a mixed methods sequential explanatory design. Data collected included 8th grade CRCT data, survey responses, and individual teacher interviews. A chi-square test revealed no improvement in the CRCT scores following the implementation of professional development on data-driven instruction (chi 2 (1) = .183, p = .67). Results from surveys and interviews revealed that teachers used data to inform their instruction, indicating time as the major hindrance to their use. Implications for social change include the development of lesson plans that will empower science teachers to deliver data-based instruction and students to achieve identified academic goals.

  11.  Evaluation of the reasons for the extraction among patients referred to the Oral Surgery Department,Faculty of Dentistry, Tehran University of Medical Sciences

    Directory of Open Access Journals (Sweden)

    Ramezanian M.

    2004-06-01

    Full Text Available Statement of Problem: Tooth extraction is always considered as the final treatment option in dentistry."nConsidering the numerous advances in dentistry, nowadays the preservation of the permanent teeth until old"nage is common. However, in most economically poor countries or those without security service insurance,"nthe high rate of extraction, particularly among restorable teeth, is regrettable."nPurpose: The aim of the present study was to determine the reasons for tooth extraction among patients"nreferred to the faculty of Dentistry, Tehran University of Medical Sciences in 2002."nMaterials and Methods: This descriptive and cross-sectional study was conducted on 320 patients. The"ninformation about patient's general knowledge, oral health status, tooth location and causes of extraction were"ncollected and recorded in a questionnaire. The data were submitted to statistical Chi-Square test."nResults: No statistically significant difference was found between two genders in their mentioned causes for"nextraction. The most prevalent reasons were as follows: Caries (50%, Periodontal diseases (16.6%. Absence"nof an acceptable occlusion, prosthetic problems, patient's request, etc... make up the remaining 33.4% of the"nreasons."nConclusion: According to this study, it is suggested to investigate extraction etiology at the society level and"nif similar results are obtained, necessary steps should be taken to prevent caries and periodontal problems as"nthe major mentioned causes for tooth extraction.

  12. Analyzing Sub-Threshold Bitcell Topologies and the Effects of Assist Methods on SRAM V<sub>MIN>

    Directory of Open Access Journals (Sweden)

    James Boley

    2012-04-01

    Full Text Available The need for ultra low power circuits has forced circuit designers to scale voltage supplies into the sub-threshold region where energy per operation is minimized [1]. The problem with this is that the traditional 6T SRAM bitcell, used for data storage, becomes unreliable at voltages below about 700 mV due to process variations and decreased device drive strength [2]. In order to achieve reliable operation, new bitcell topologies and assist methods have been proposed. This paper provides a comparison of four different bitcell topologies using read and write V<sub>MIN> as the metrics for evaluation. In addition, read and write assist methods were tested using the periphery voltage scaling techniques discussed in [4–13]. Measurements taken from a 180 nm test chip show read functionality (without assist methods down to 500 mV and write functionality down to 600 mV. Using assist methods can reduce both read and write V<sub>MIN> by 100 mV over the unassisted test case.

  13. The responses of endothelial cells to Zr{sub 61}Ti{sub 2}Cu{sub 25}Al{sub 12} metallic glass in vitro and in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jing, E-mail: monkeys0109@sina.com; Ai, Hong-jun

    2014-07-01

    The goal of this study was to evaluate the biocompatibility of newly developed Zr{sub 61}Ti{sub 2}Cu{sub 25}Al{sub 12} metallic glass (denoted ZT1) and its parallel material, commercially pure titanium (CP-Ti), as dental implants. To this end, we evaluated their cytotoxicity in vitro using human umbilical vein endothelial cells (HUVECs) and in vivo by performing an oral mucosa irritation test in hamsters. Specifically, cytotoxicity was determined in HUVECs by evaluating their cell morphology using scanning electron microscopy (SEM) and their cell viability using CCK-8 assays. Moreover, we examined the mRNA levels of vascular endothelial growth factor and von Willebrand factor by quantitative PCR (qPCR). In the early stages of proliferation and differentiation, no differences were observed between HUVECs inoculated on ZT1 compared to those on CP-Ti. However, in the later stages of proliferation and differentiation, the HUVECs inoculated on ZT1 were significantly better than the cells cultured on CP-Ti. In the oral mucosa irritation test, we sutured sample discs into the cheek pouch of hamsters. After 2, 3, and 4 weeks, we harvested the corresponding mucosal tissues, stained them with hematoxylin and eosin, obtained blood samples for biochemical analysis, and finally, observed the topography of the sample discs by SEM. Immunohistochemistry and hematology analyses showed no differences in the biocompatibility of ZT1 and CP-Ti, and neither of these compounds caused irritation of the mucosa. In addition, SEM images showed that no pitting occurred on the sample discs. Together, these data indicate that ZT1 may be a good candidate for dental implants and should be further studied. - Graphical abstract: The results of blood analysis. (a) WBC, (b) Mon %, (c) Neu %, and (d) Eos %. - Highlights: • We used HUVECs to evaluate the cytotoxicity of Zr{sub 61}Ti{sub 2}Cu{sub 25}Al{sub 12} BMG. • We are the first to evaluate Zr{sub 61}Ti{sub 2}Cu{sub 25}Al{sub 12} BMG using an

  14. Sub-arc narrow gap welding of Atucha 2 RPV closure head

    International Nuclear Information System (INIS)

    Hantsch, H.; Million, K.; Zimmermann, H.

    1982-01-01

    Narrow gap technology was used for reasons of design and fabrication when welding the closure-head dome to its flange. Preliminary tests had yielded the necessary improvements of the well-proven sub-arc practice. New facilities had to be developed for welding proper and for the accompanying machining work (finishing in the narrow gap). Special measures were adopted for monitoring the welding process and for recording the welding parameters. The new method was tried out on several large test coupons before welding of the final product was started. No difficulties were encountered during the welding job. Fabrication of the closure head is shown in a short film sequence. (orig.)

  15. Impedance spectroscopy of p-ZnGa{sub 2}Te{sub 4}/n-Si nano-HJD

    Energy Technology Data Exchange (ETDEWEB)

    Fouad, S.S. [Thin film Laboratory, Department of Physics, Faculty of Education, Ain Shams University, Roxy, Cairo (Egypt); Sakr, G.B. [Nano-Science Laboratory, Physics Department, Faculty of Education, Ain Shams University, Roxy, Cairo (Egypt); Yahia, I.S., E-mail: dr_isyahia@yahoo.com [Nano-Science Laboratory, Physics Department, Faculty of Education, Ain Shams University, Roxy, Cairo (Egypt); Semiconductor Laboratory, Physics Department, Faculty of Education, Ain Shams University, Roxy, Cairo (Egypt); Department of Physics, Faculty of Science, King Khalid University, P.O. Box 9004, Abha (Saudi Arabia); Abdel-Basset, D.M. [Nano-Science Laboratory, Physics Department, Faculty of Education, Ain Shams University, Roxy, Cairo (Egypt); Yakuphanoglu, F. [Department of Physics, Faculty of Science, Firat University, Elazig (Turkey)

    2013-04-15

    The dielectric relaxation and alternating current mechanisms of nano-crystalline p-ZnGa{sub 2}Te{sub 4}/n-Si heterojunction diode (HJD) were investigated by complex impedance spectroscopy over a wide range of temperature (297–473 K) and a frequency range (42 Hz–5 MHz). The bulk resistance R{sub b} as well as the bulk capacitance C{sub b} were found to increase with increasing temperature. The dc conductivity exhibits a typical Arrhenius behavior. The electrical activation energy ΔE{sub σ} was determined to be (0.28 eV). The ac conductivity spectrum was found to obey Jonscher's universal power law. The frequency exponent s decreases slightly with increasing temperature. The temperature dependence of ac conductivity can be reasonably interpreted in terms of the correlated barrier hopping (CBH) model. The dielectric constant ε{sub 1}(ω) and dielectric loss ε{sub 2}(ω) were found to decrease with increasing frequency and to increase with increasing temperature. The mean value of the exponent m decreases with increasing temperature. The dielectric analysis is described by non-Debye type behavior.

  16. Synthesis and characterization of Mn{sub 0.5}Zn{sub 0.5}Fe{sub 2}O{sub 4} and Fe{sub 3}O{sub 4} nanoparticle ferrofluids for thermo-electric conversion

    Energy Technology Data Exchange (ETDEWEB)

    Sansom, C.L., E-mail: c.l.sansom@cranfield.ac.uk [Cranfield University, Cranfield MK43 0AL (United Kingdom); Jones, P.; Dorey, R.A.; Beck, C.; Stanhope-Bosumpim, A. [Cranfield University, Cranfield MK43 0AL (United Kingdom); Peterson, J. [Peterson Dynamics Ltd., 9 Nant y Gamar Road, Craig y Don LL30 1YE (United Kingdom)

    2013-06-15

    Ferrofluids containing nanoparticles of Mn{sub 0.5}Zn{sub 0.5}Fe{sub 2}O{sub 4} (MZ5) and Fe{sub 3}O{sub 4} (magnetite) have been examined as potential thermal transport media and energy harvesting materials. The ferrofluids were synthesized by chemical co-precipitation and characterized by EDX to determine composition and by TEM to determine particle size and agglomeration. A range of particle coatings and carrier fluids were used to complete the fluid preparation. Commercially available ferrofluids were tested in custom built rigs to demonstrate both thermal pumping (for waste heat removal applications) and power induction (for power conversion and energy harvesting applications). The results indicate that simple ferrofluids possess the necessary properties to remove waste heat, either into thermal storage or for conversion to electrical power. - Highlights: ► The synthesis of nanoparticle ferrofluids based on Mn{sub 0.5}Zn{sub 0.5}Fe{sub 2}O{sub 4} and Fe{sub 3}O{sub 4} is reported. ► The thermal properties of the ferrofluids creates a novel pump with no moving parts. ► Thermal energy harvesting for conversion into electrical power is demonstrated.

  17. Substrate-dependent Au{sub x} cluster: A new insight into Au{sub x}/CeO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Kong-Jie; Yang, Yan-Ju [School of Chemistry and Life Science, Zhejiang Normal University, Jinhua 321004 (China); Lang, Jia-Jian [School of Chemistry and Life Science, Zhejiang Normal University, Jinhua 321004 (China); Engineering Laboratory of Specialty Fibers and Nuclear Energy Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201 (China); Teng, Bo-Tao, E-mail: tbt@zjnu.cn [School of Chemistry and Life Science, Zhejiang Normal University, Jinhua 321004 (China); Wu, Feng-Min [School of Chemistry and Life Science, Zhejiang Normal University, Jinhua 321004 (China); Du, Shi-Yu [Engineering Laboratory of Specialty Fibers and Nuclear Energy Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201 (China); Wen, Xiao-Dong, E-mail: wxd@sxicc.ac.cn [State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001 (China)

    2016-11-30

    Graphical abstract: 2D Au{sub x} (x < 10) on CeO{sub 2}(110) are more stable than 3D ones, while the stability trend changes for x ≥ 10; Au{sub x} (x ≤ 4) prefer to monatomically disperse on CeO{sub 2}(100) and aggregate to 3D clusters for x > 4. - Highlights: • The stable structures of Au{sub x}/CeO{sub 2} are dependent of index surfaces of CeO{sub 2}. • Au{sub x} prefers to monatomically disperse on CeO{sub 2}(100) at low coverage. • Au{sub x} aggregates to 3D clusters on CeO{sub 2}(100) at high coverage. • 2D Au{sub x} (x < 10) are more stable than the 3D ones on CeO{sub 2}(110). • The effects on the stability of Au{sub x}/CeO{sub 2} are systematically discussed. - Abstract: To theoretically study the structures of metal clusters on oxides is very important and becomes one of the most challenging works in computational heterogeneous catalysis since many factors affect their structures and lead to various possibilities. In this work, it is very interesting to find that the stable structures and stability evolution of Au{sub x} clusters on ceria are varied with different index surfaces of CeO{sub 2}. The corresponding reasons in chemical, geometric and electronic properties are systematically explored. Au{sub x} (x = 1–4) clusters prefer to separately disperse at the O-O bridge sites on CeO{sub 2}(100) due to the low coordination number of surface O; while aggregate due to the strong Au–Au attractions when x is larger than 4. Owing to the uniform distribution of O-O bridge sites on CeO{sub 2}(111) and (100), the most stable configurations of Au{sub x} are 3D structures with bottom atoms more than top ones when x is larger than 4. However, 2D configurations of Au{sub x}/CeO{sub 2}(110) (x < 10) are more stable than the corresponding 3D structures due to the particular O-O arrangement on CeO{sub 2}(110). 3D Au{sub x} clusters across O-O-Y lines are suggested as the most stable configurations for Au{sub x}/CeO{sub 2}(110) (x ≥ 10). The present

  18. Integrated Data Collection Analysis (IDCA) Program - KClO<sub>3sub>/Dodecane Mixture

    Energy Technology Data Exchange (ETDEWEB)

    Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Sorenson, Daniel N. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Shelley, Timothy J. [Air Force Research Lab. (AFRL), Tyndall AFB, FL (United States); Whinnery, LeRoy L. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2011-05-23

    The Integrated Data Collection Analysis (IDCA) program is conducting a proficiency study for Small-Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the results for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis of a mixture of KClO<sub>3sub> and dodecane—KClO<sub>3sub>/dodecane mixture. This material was selected because of the challenge of performing SSST testing of a mixture of solid and liquid materials. The mixture was found to: 1) be more sensitive to impact than RDX, and PETN, 2) less sensitive to friction than PETN, and 3) less sensitive to spark than RDX. The thermal analysis showed little or no exothermic features suggesting that the dodecane volatilized at low temperatures. A prominent endothermic feature was observed assigned to melting of KClO<sub>3sub>. This effort, funded by the Department of Homeland Security (DHS), ultimately will put the issues of safe handling of these materials in perspective with standard military explosives. The study is adding SSST testing results for a broad suite of different HMEs to the literature. Ultimately the study has the potential to suggest new guidelines and methods and possibly establish the SSST testing accuracies needed to develop safe handling practices for HMEs. Each participating testing laboratory uses identical test materials and preparation methods wherever possible. Note, however, the test procedures differ among the laboratories. The results are compared among the laboratories and then compared to historical data from various sources. The testing performers involved for the KClO<sub>3sub>/dodecane mixture are Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), and Indian Head Division, Naval Surface Warfare Center, (NSWC IHD). These tests are conducted as a proficiency study in order to establish some consistency in test protocols, procedures, and experiments and to understand

  19. Integrating Intelligent Systems Domain Knowledge Into the Earth Science Curricula

    Science.gov (United States)

    Güereque, M.; Pennington, D. D.; Pierce, S. A.

    2017-12-01

    High-volume heterogeneous datasets are becoming ubiquitous, migrating to center stage over the last ten years and transcending the boundaries of computationally intensive disciplines into the mainstream, becoming a fundamental part of every science discipline. Despite the fact that large datasets are now pervasive across industries and academic disciplines, the array of skills is generally absent from earth science programs. This has left the bulk of the student population without access to curricula that systematically teach appropriate intelligent-systems skills, creating a void for skill sets that should be universal given their need and marketability. While some guidance regarding appropriate computational thinking and pedagogy is appearing, there exist few examples where these have been specifically designed and tested within the earth science domain. Furthermore, best practices from learning science have not yet been widely tested for developing intelligent systems-thinking skills. This research developed and tested evidence based computational skill modules that target this deficit with the intention of informing the earth science community as it continues to incorporate intelligent systems techniques and reasoning into its research and classrooms.

  20. Design of Composite Structures Using Knowledge-Based and Case Based Reasoning

    Science.gov (United States)

    Lambright, Jonathan Paul

    1996-01-01

    A method of using knowledge based and case based reasoning to assist designers during conceptual design tasks of composite structures was proposed. The cooperative use of heuristics, procedural knowledge, and previous similar design cases suggests a potential reduction in design cycle time and ultimately product lead time. The hypothesis of this work is that the design process of composite structures can be improved by using Case-Based Reasoning (CBR) and Knowledge-Based (KB) reasoning in the early design stages. The technique of using knowledge-based and case-based reasoning facilitates the gathering of disparate information into one location that is easily and readily available. The method suggests that the inclusion of downstream life-cycle issues into the conceptual design phase reduces potential of defective, and sub-optimal composite structures. Three industry experts were interviewed extensively. The experts provided design rules, previous design cases, and test problems. A Knowledge Based Reasoning system was developed using the CLIPS (C Language Interpretive Procedural System) environment and a Case Based Reasoning System was developed using the Design Memory Utility For Sharing Experiences (MUSE) xviii environment. A Design Characteristic State (DCS) was used to document the design specifications, constraints, and problem areas using attribute-value pair relationships. The DCS provided consistent design information between the knowledge base and case base. Results indicated that the use of knowledge based and case based reasoning provided a robust design environment for composite structures. The knowledge base provided design guidance from well defined rules and procedural knowledge. The case base provided suggestions on design and manufacturing techniques based on previous similar designs and warnings of potential problems and pitfalls. The case base complemented the knowledge base and extended the problem solving capability beyond the existence of

  1. Integrated Data Collection Analysis (IDCA) Program - KClO<sub>4sub>/Aluminum Mixture

    Energy Technology Data Exchange (ETDEWEB)

    Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (NSWC IHD), Indian Head, MD (United States). Indian Head Division; Sorensen, Daniel N. [Naval Surface Warfare Center (NSWC IHD), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (NSWC IHD), Indian Head, MD (United States). Indian Head Division; Whinnery, LeRoy L. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Shelley, Timothy J. [Air Force Research Lab. (AFRL), Tyndall AFB, FL (United States); Reyes, Jose A. [Applied Research Associates (ARA), Tyndall AFB, FL (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2012-01-17

    The Integrated Data Collection Analysis (IDCA) program is conducting a Proficiency Test for Small-Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the results for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis of a mixture of KClO<sub>4sub> and aluminum—KClO<sub>4sub>/Al mixture. This material was selected because of the challenge of performing SSST testing of a mixture of two solids. The mixture was found to be: 1) much less sensitive to impact than RDX, (LLNL being the exception) and PETN, 2) more sensitive to friction than RDX and PETN, and 3) extremely sensitive to spark. The thermal analysis showed little or no exothermic character. One prominent endothermic feature was observed in the temperature range studied and identified as a phase transition of KClO<sub>4sub>.

  2. Description and crystal structure of albrechtschraufite, MgCa{sub 4}F{sub 2}[UO{sub 2}(CO{sub 3}){sub 3}]{sub 2}.17-18H{sub 2}O

    Energy Technology Data Exchange (ETDEWEB)

    Mereiter, K. [Vienna Univ. of Technology (Austria). Inst. of Chemical Technologies and Analytics

    2013-04-15

    Albrechtschraufite, MgCa{sub 4}F{sub 2}[UO{sub 2}(CO{sub 3}){sub 3}]{sub 2}.17-18H{sub 2}O, triclinic, space group P anti 1, a = 13.569(2), b = 13.419(2), c = 11.622(2) Aa, α = 115.82(1), β = 107.61(1), γ = 92.84(1) (structural unit cell, not reduced), V = 1774.6(5) Aa{sup 3}, Z = 2, Dc = 2.69 g/cm{sup 3} (for 17.5 H{sub 2}O), is a mineral that was found in small amounts with schroeckingerite, NaCa{sub 3}F[UO{sub 2}(CO{sub 3}){sub 3}](SO{sub 4}).10H{sub 2}O, on a museum specimen of uranium ore from Joachimsthal (Jachymov), Czech Republic. The mineral forms small grain-like subhedral crystals (= 0.2 mm) that resemble in appearance liebigite, Ca{sub 2}[UO{sub 2}(CO{sub 3}){sub 3}]. ∝ 11H{sub 2}O. Colour pale yellow-green, luster vitreous, transparent, pale bluish green fluorescence under ultraviolet light. Optical data: Biaxial negative, nX = 1.511(2), nY = 1.550(2), nZ = 1.566(2), 2V = 65(1) (λ = 589 nm), r < v weak. After qualitative tests had shown the presence of Ca, U, Mg, CO{sub 2} and H{sub 2}O, the chemical formula was determined by a crystal structure analysis based on X-ray four-circle diffractometer data. The structure was later on refined with data from a CCD diffractometer to R1 = 0.0206 and wR2 = 0.0429 for 9,236 independent observed reflections. The crystal structure contains two independent [UO{sub 2}(CO{sub 3}){sub 3}]{sup 4-} anions of which one is bonded to two Mg and six Ca while the second is bonded to only one Mg and three Ca. Magnesium forms a MgF{sub 2}(O{sub carbonate}){sub 3}(H{sub 2}O) octahedron that is linked via the F atoms with three Ca atoms so as to provide each F atom with a flat pyramidal coordination by one Mg and two Ca. Calcium is 7- and 8-coordinate forming CaFO{sub 6}, CaF{sub 2}O{sub 2}(H{sub 2}O){sub 4}, CaFO{sub 3}(H{sub 2}O){sub 4} and CaO{sub 2}(H{sub 2}O){sub 6} coordination polyhedra. The crystal structure is built up from MgCa{sub 3}F{sub 2}[UO{sub 2}(CO{sub 3}){sub 3}].8H{sub 2}O layers parallel to (001) which

  3. Fabrication and tests of anode supported solid oxide fuel cell; Fabricacao e testes de celula a combustivel de oxido solido suportada no anodo

    Energy Technology Data Exchange (ETDEWEB)

    Florio, D.Z. de [UNESP, Araraquara, SP (Brazil)], e-mail: dzflorio@ipen.br; Fonseca, F.C.; Franca, Y.V.; Muccillo, E.N.S.; Muccillo, R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Berton, M.A.C.; Garcia, C.M. [LACTEC - Instituto de Tecnologia para o Desenvolvimento, Curitiba, PR (Brazil)

    2006-07-01

    A laboratory setup was designed and put into operation for the development of solid oxide fuel cells (SOFCs). Ceramic single cells were fabricated by low-cost methods, and emphasis was given to the use of ready available raw materials. The whole project consisted of the preparation of the component materials - anode, cathode, and electrolyte - and the buildup of a hydrogen leaking-free sample chamber with platinum leads and current collectors for measuring the electrochemical properties of single SOFCs. Anode-supported single SOFCs of the type (ZrO{sub 2}:Y{sub 2}O{sub 3} + NiO) anode / (ZrO{sub 2}:Y{sub 2}O{sub 3}) electrolyte / (La{sub 0.65}Sr{sub 0.35}MnO{sub 3} + ZrO{sub 2}:Y{sub 2}O{sub 3}) cathode have been prepared and tested at 700 deg C and 800 deg C after in situ H{sub 2} anode reduction. The main results show that the slurry coating method resulted in single-cells with good reproducibility and reasonable performance, suggesting that this method can be considered for fabrication of SOFCs. (author)

  4. Students' reasons for preferring teleological explanations

    Science.gov (United States)

    Trommler, Friederike; Gresch, Helge; Hammann, Marcus

    2018-01-01

    The teleological bias, a major learning obstacle, involves explaining biological phenomena in terms of purposes and goals. To probe the teleological bias, researchers have used acceptance judgement tasks and preference judgement tasks. In the present study, such tasks were used with German high school students (N = 353) for 10 phenomena from human biology, that were explained both teleologically and causally. A sub-sample (n = 26) was interviewed about the reasons for their preferences. The results showed that the students favoured teleological explanations over causal explanations. Although the students explained their preference judgements etiologically (i.e. teleologically and causally), they also referred to a wide range of non-etiological criteria (i.e. familiarity, complexity, relevance and five more criteria). When elaborating on their preference for causal explanations, the students often focused not on the causality of the phenomenon, but on mechanisms whose complexity they found attractive. When explaining their preference for teleological explanations, they often focused not teleologically on purposes and goals, but rather on functions, which they found familiar and relevant. Generally, students' preference judgements rarely allowed for making inferences about causal reasoning and teleological reasoning, an issue that is controversial in the literature. Given that students were largely unaware of causality and teleology, their attention must be directed towards distinguishing between etiological and non-etiological reasoning. Implications for educational practice as well as for future research are discussed.

  5. Using Analogy to Improve Abstract Conditional Reasoning in Adolescents: Not as Easy as It Looks

    Science.gov (United States)

    Markovits, Henry; Doyon, Celine

    2011-01-01

    Abstract reasoning refers to the ability to reason logically with premises that do not allow reference to knowledge about the real world. This form of reasoning is complex and difficult, and at the same time, it is critical for understanding science and mathematics. Two studies examined the use of analogy as a method to bridge reasoning with…

  6. V/V/sub m/ test for quasars: A new interpretation

    International Nuclear Information System (INIS)

    Hawkins, M.R.S.; Stewart, N.J.

    1981-01-01

    The V/V/sub m/ test is discussed, and it is suggested that if certain problem of misidentification are not taken into account, the expected value for without evolution is not 1/2 , but depends on the quasar luminosity function and is compatible with currently observed values of about 0.68. A complete sample of quasars is examined, and it appears that beyond a redshift of about 0.5, the evidence for evolution is not strong. Differences in the value of for steep and flat spectrum quasars can be simply explained as differences in luminosity function

  7. Measuring scientific reasoning through behavioral analysis in a computer-based problem solving exercise

    Science.gov (United States)

    Mead, C.; Horodyskyj, L.; Buxner, S.; Semken, S. C.; Anbar, A. D.

    2016-12-01

    Developing scientific reasoning skills is a common learning objective for general-education science courses. However, effective assessments for such skills typically involve open-ended questions or tasks, which must be hand-scored and may not be usable online. Using computer-based learning environments, reasoning can be assessed automatically by analyzing student actions within the learning environment. We describe such an assessment under development and present pilot results. In our content-neutral instrument, students solve a problem by collecting and interpreting data in a logical, systematic manner. We then infer reasoning skill automatically based on student actions. Specifically, students investigate why Earth has seasons, a scientifically simple but commonly misunderstood topic. Students are given three possible explanations and asked to select a set of locations on a world map from which to collect temperature data. They then explain how the data support or refute each explanation. The best approaches will use locations in both the Northern and Southern hemispheres to argue that the contrasting seasonality of the hemispheres supports only the correct explanation. We administered a pilot version to students at the beginning of an online, introductory science course (n = 223) as an optional extra credit exercise. We were able to categorize students' data collection decisions as more and less logically sound. Students who choose the most logical measurement locations earned higher course grades, but not significantly higher. This result is encouraging, but not definitive. In the future, we will clarify our results in two ways. First, we plan to incorporate more open-ended interactions into the assessment to improve the resolving power of this tool. Second, to avoid relying on course grades, we will independently measure reasoning skill with one of the existing hand-scored assessments (e.g., Critical Thinking Assessment Test) to cross-validate our new

  8. Bio diesel synthesis from pongamia pinnata oil over modified CeO{sub 2} catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Venkatesh; Sathgatta Z, M. S.; Manjunatha, S.; Thammannigowda V, V., E-mail: mohamed.shamshuddin@gmail.com [HMS Institute of Technology, Chemistry Research Laboratory, NH4, Kyathsandra, Tumkur, 572104 Karnataka (India)

    2014-07-01

    This study investigates the use of CeO{sub 2}, ZrO{sub 2}, Mg O and CeO{sub 2}-ZrO{sub 2}, CeO{sub 2}-Mg O, CeO{sub 2}-ZrO{sub 2}-Mg O mixed oxides as solid base catalysts for the transesterification of Pongamia pinnata oil with methanol to produce bio diesel. SO{sub 4}{sup 2-}/CeO{sub 2} and SO{sub 4}{sup 2-}/CeO{sub 2}-ZrO{sub 2} were also prepared and used as solid acid catalysts for esterification of Pongamia pinnata oil (P-oil) to reduce the % of free fatty acid (FFA) in P-oil. The oxide catalysts were prepared by an incipient wetness impregnation method and characterized by techniques such as NH{sub 3}-Tpd for surface acidity, CO{sub 2}-Tpd for surface basicity and powder X-ray diffraction for crystallinity. The effect of nature of the catalyst, methanol to P-oil molar ratio and reaction time in esterification as well as in transesterification was investigated. The catalytic materials were reactive d and reused for five reaction cycles and the results showed that the ceria based catalysts have reasonably good reusability both in esterification and transesterification reaction. The test results also revealed that the CeO{sub 2}-ZrO{sub 2} modified with Mg O could have potential for use in the large scale bio diesel production. (Author)

  9. Bioactivity studies on TiO{sub 2}-bearing Na{sub 2}O–CaO–SiO{sub 2}–B{sub 2}O{sub 3} glasses

    Energy Technology Data Exchange (ETDEWEB)

    Jagan Mohini, G. [Department of Physics, Andhra Loyola College, Vijayawada 520 008, Andhra Pradesh (India); Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar 522 510, A.P. (India); Sahaya Baskaran, G. [Department of Physics, Andhra Loyola College, Vijayawada 520 008, Andhra Pradesh (India); Ravi Kumar, V. [Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar 522 510, A.P. (India); Piasecki, M. [Institute of Physics, J. Dlugosz University, Al. Armii Krajowej 13/15, Czestochowa (Poland); Veeraiah, N., E-mail: nvr8@rediffmail.com [Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar 522 510, A.P. (India)

    2015-12-01

    Soda lime silica borate glasses mixed with different concentrations of TiO{sub 2} are synthesized by the melt-quenching technique. As a part of study on bioactivity of these glasses, the samples were immersed in simulated body fluid (SBF) solution for prolonged times (~ 21 days) during which weight loss along with pH measurements is carried out at specific intervals of time. The XRD and SEM analyses of post-immersed samples confirm the formation of crystalline hydroxyapatite layer (HA) on the surface of the samples. To assess the role of TiO{sub 2} on the formation of HA layer and degradability of the samples the spectroscopic studies viz. optical absorption and IR spectral studies on post- and pre-immersed samples have been carried out. The analysis of the results of degradability together with spectroscopic studies as a function of TiO{sub 2} concentration indicated that about 6.0 mol% of TiO{sub 2} is the optimal concentration for achieving better bioactivity of these glasses. The presence of the maximal concentration octahedral titanium ions in this glass that facilitates the formation of HA layer is found to be the reason for such a higher bioactivity. - Highlights: • Soda lime silica borate glasses mixed with TiO{sub 2} are synthesized. • Bioactivity of the glasses is studied by immersing them in SBF solution. • XRD and SEM studies indicated the formation of hydroxyapatite layer on the surface. • Quantum of degradability is the highest in the glasses mixed with 6.0 mol% of TiO{sub 2.} • The results are analyzed using IR and optical absorption studies.

  10. Recovery Act: Web-based CO{sub 2} Subsurface Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Paolini, Christopher; Castillo, Jose

    2012-11-30

    The Web-based CO{sub 2} Subsurface Modeling project focused primarily on extending an existing text-only, command-line driven, isothermal and isobaric, geochemical reaction-transport simulation code, developed and donated by Sienna Geodynamics, into an easier-to-use Web-based application for simulating long-term storage of CO{sub 2} in geologic reservoirs. The Web-based interface developed through this project, publically accessible via URL http://symc.sdsu.edu/, enables rapid prototyping of CO{sub 2} injection scenarios and allows students without advanced knowledge of geochemistry to setup a typical sequestration scenario, invoke a simulation, analyze results, and then vary one or more problem parameters and quickly re-run a simulation to answer what-if questions. symc.sdsu.edu has 2x12 core AMD Opteron™ 6174 2.20GHz processors and 16GB RAM. The Web-based application was used to develop a new computational science course at San Diego State University, COMP 670: Numerical Simulation of CO{sub 2} Sequestration, which was taught during the fall semester of 2012. The purpose of the class was to introduce graduate students to Carbon Capture, Use and Storage (CCUS) through numerical modeling and simulation, and to teach students how to interpret simulation results to make predictions about long-term CO{sub 2} storage capacity in deep brine reservoirs. In addition to the training and education component of the project, significant software development efforts took place. Two computational science doctoral and one geological science masters student, under the direction of the PIs, extended the original code developed by Sienna Geodynamics, named Sym.8. New capabilities were added to Sym.8 to simulate non-isothermal and non-isobaric flows of charged aqueous solutes in porous media, in addition to incorporating HPC support into the code for execution on many-core XSEDE clusters. A successful outcome of this project was the funding and training of three new computational

  11. Inductive Reasoning in Patients with Paranoid Type Schizophrenia

    OpenAIRE

    Mehmet Emrah Karadere; Yasir Safak; Halime Seyma Ozcelik; Emre Demir; Mehmet Hakan Turkcapar

    2017-01-01

    The goal of our study is to evaluate the decision making and reasoning of the paranoid type schizophrenic patients, and their confidence in reasoning and perseverance in keeping to their decisions via using Reasoning with Inductive Argument Test (RIAT). Thirty-two delusional patients and 30 healthy volunteers were included in the study. After the diagnostic interview was conducted by SCID-I to the patients who were asked to participate in the study, RIAT test was applied by the interviewe...

  12. Scientific reasoning abilities in kindergarten: dynamic assessment of the control of variables strategy

    NARCIS (Netherlands)

    Graaf, J. van der; Segers, P.C.J.; Verhoeven, L.T.W.

    2015-01-01

    A dynamic assessment tool was developed and validated using Mokken scale analysis to assess the extent to which kindergartners are able to construct unconfounded experiments, an essential part of scientific reasoning. Scientific reasoning is one of the learning processes happening within science

  13. CO<sub>2sub> Binding Organic Liquids Gas Capture with Polarity Swing Assisted Regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Heldebrant, David [Battelle Memorial Institute, Columbus, OH (United States)

    2014-05-31

    This report outlines the comprehensive bench-scale testing of the CO<sub>2sub>-binding organic liquids (CO<sub>2sub>BOLs) solvent platform and its unique Polarity Swing Assisted Regeneration (PSAR). This study outlines all efforts on a candidate CO<sub>2sub>BOL solvent molecule, including solvent synthesis, material characterization, preliminary toxicology studies, and measurement of all physical, thermodynamic and kinetic data, including bench-scale testing. Equilibrium and kinetic models and analysis were made using Aspen Plus™. Preliminary process configurations, a technoeconomic assessment and solvent performance projections for separating CO<sub>2sub> from a subcritical coal-fired power plant are compared to the U.S. Department of Energy's Case 10 monoethanolamine baseline.

  14. Performance of La{sub 0.75}Sr{sub 0.25}Cr{sub 0.5}Mn{sub 0.5}O{sub 3-{delta}} perovskite-structure anode material at lanthanum gallate electrolyte for IT-SOFC running on ethanol fuel

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Bo; Wang, S.R.; Liu, R.Z.; Ye, X.F.; Nie, H.W.; Sun, X.F.; Wen, T.L. [Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS), 1295 Dingxi Road, Shanghai 200050 (China)

    2007-05-01

    Perovskite-structure La{sub 0.75}Sr{sub 0.25}Cr{sub 0.5}Mn{sub 0.5}O{sub 3-{delta}} (LSCM) powders were prepared using a simple combustion process. Thermal analysis was carried out on the perovskite precursor to investigate the oxide-phase formation. The structural phase of the powders was determined by X-ray diffraction. These results showed that the decomposition of the precursors occurs in a two-step reaction and temperatures higher than 1100 C are required for these decomposition reactions. For the electrochemical characterization, LSCM anode materials and (Pr{sub 0.7}Ca{sub 0.3}){sub 0.9}MnO{sub 3} (PCM) cathode materials were screen-printed on two sides of dense La{sub 0.8}Sr{sub 0.2}Ga{sub 0.8}Mg{sub 0.2}O{sub 3} (LSGM) electrolyte layers prepared by tape casting with a thickness of about 600 {mu}m, respectively. The morphology of the screen-printed La{sub 0.75}Sr{sub 0.25}Cr{sub 0.5}Mn{sub 0.5}O{sub 3-{delta}} perovskite thick films (65 {mu}m) was investigated by field emission scanning electron microscope and showed a porous microstructure. In addition, fuel cell tests were carried out using humidified hydrogen or ethanol stream as fuel and oxygen as oxidant. The performance of the conventional electrolyte-supported cell LSCM/LSGM/PCM while operating on humidified hydrogen was modest with a maximum power density of 165, 99 and 62 mW cm{sup -2} at 850, 800 and 750 C, respectively, the corresponding values for the cell while operating on ethanol stream was 160, 101 and 58 mW cm{sup -2}, respectively. Cell stability tests indicate no significant degradation in performance has been observed after 60 h of cell testing when LSCM anode was exposed to ethanol steam at 750 C, suggesting that carbon deposition was limited during cell operation. (author)

  15. Assessment of Factors Influencing Effective CO<sub>2sub> Storage Capacity and Injectivity in Eastern Gas Shales

    Energy Technology Data Exchange (ETDEWEB)

    Godec, Michael [Advanced Resources International, Inc., Arlington, VA (United States)

    2013-06-30

    Building upon advances in technology, production of natural gas from organic-rich shales is rapidly developing as a major hydrocarbon supply option in North America and around the world. The same technology advances that have facilitated this revolution - dense well spacing, horizontal drilling, and hydraulic fracturing - may help to facilitate enhanced gas recovery (EGR) and carbon dioxide (CO<sub>2sub>) storage in these formations. The potential storage of CO<sub>2sub> in shales is attracting increasing interest, especially in Appalachian Basin states that have extensive shale deposits, but limited CO<sub>2sub> storage capacity in conventional reservoirs. The goal of this cooperative research project was to build upon previous and on-going work to assess key factors that could influence effective EGR, CO<sub>2sub> storage capacity, and injectivity in selected Eastern gas shales, including the Devonian Marcellus Shale, the Devonian Ohio Shale, the Ordovician Utica and Point Pleasant shale and equivalent formations, and the late Devonian-age Antrim Shale. The project had the following objectives: (1) Analyze and synthesize geologic information and reservoir data through collaboration with selected State geological surveys, universities, and oil and gas operators; (2) improve reservoir models to perform reservoir simulations to better understand the shale characteristics that impact EGR, storage capacity and CO<sub>2sub> injectivity in the targeted shales; (3) Analyze results of a targeted, highly monitored, small-scale CO<sub>2sub> injection test and incorporate into ongoing characterization and simulation work; (4) Test and model a smart particle early warning concept that can potentially be used to inject water with uniquely labeled particles before the start of CO<sub>2sub> injection; (5) Identify and evaluate potential constraints to economic CO<sub>2sub> storage in gas shales, and propose development approaches that overcome these constraints

  16. Li{sub 4}SiO{sub 4} based breeder ceramics with Li{sub 2}TiO{sub 3}, LiAlO{sub 2} and Li{sub X}La{sub Y}TiO{sub 3} additions, part II: Pebble properties

    Energy Technology Data Exchange (ETDEWEB)

    Kolb, M.H.H., E-mail: Matthias.kolb@kit.edu [Karlsruhe Institute of Technology, Institute for Applied Materials, PO Box 3640, 76021, Karlsruhe (Germany); Knitter, R. [Karlsruhe Institute of Technology, Institute for Applied Materials, PO Box 3640, 76021, Karlsruhe (Germany); Hoshino, T. [Breeding Functional Materials Development Group, Department of Blanket Systems Research, Rokkasho Fusion Institute, Fusion Energy Research and Development Directorate, National Institutes for Quantum and Radiological Science and Technology (QST) (Japan)

    2017-02-15

    Highlights: • The mechanical strength of Li{sub 4}SiO{sub 4}-based breeder pebbles can be improved by adding either LMT, LAO or LLTO as second phase. • The increase in strength is closely linked to a reduction of the open porosity of the pebbles. • All fabricated pebbles show a highly homogenous microstructure with mostly low closed porosity. • Adding LLTO, although it decomposes during sintering, greatly improves the strength of the pebbles. - Abstract: The pebble properties of novel two-phase Li{sub 4}SiO{sub 4} pebbles of 1 mm diameter with additions of Li{sub 2}TiO{sub 3}, LiAlO{sub 2} or Li{sub x}La{sub y}TiO{sub 3} are evaluated in this work as a function of the second phase concentration and the microstructure of the pebbles. The characterization focused on the mechanical strength, microstructure and open as well as closed porosity. Therefore crush load tests, SEM analyses as well as helium pycnometry and optical image analysis were performed, respectively. This work shows that generally additions of a second phase to Li{sub 4}SiO{sub 4} considerably improve the mechanical strength. It also shows that the fabrication processes have to be well-controlled to achieve high mechanical strengths. When Li{sub 2}TiO{sub 3} is added in different concentrations, the determinant for the crush load seems to be the open porosity of the pebbles. The strengthening effect of LiAlO{sub 2} compared to Li{sub 2}TiO{sub 3} is similar, while additions of Li{sub x}La{sub y}TiO{sub 3} increase the mechanical strength much more. Yet, Li{sub 4}SiO{sub 4} and Li{sub x}La{sub y}TiO{sub 3} react with each other to a number of different phases upon sintering. In general the pebble properties of all samples are favorable for use within a fusion breeder blanket.

  17. Integrated Data Collection Analysis (IDCA) Program - KClO<sub>4sub>/Carbon Mixture

    Energy Technology Data Exchange (ETDEWEB)

    Sandstrom, Mary M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brown, Geoffrey W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Preston, Daniel N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pollard, Colin J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Warner, Kirstin F. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Sorensen, Daniel N. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Remmers, Daniel L. [Naval Surface Warfare Center (NSWC), Indian Head, MD (United States). Indian Head Division; Shelley, Timothy J. [Air Force Research Lab. (AFRL), Tyndall AFB, FL (United States); Reyes, Jose A. [Applied Research Associates, Tyndall AFB, FL (United States); Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2013-01-31

    The Integrated Data Collection Analysis (IDCA) program is conducting a proficiency study for Small- Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the results for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis of a mixture of KClO<sub>4sub> and activated carbon—KClO<sub>4sub>/C mixture. This material was selected because of the challenge of performing SSST testing of a mixture of two solids. The mixture was found to be insensitive to impact, friction, and thermal stimulus, and somewhat sensitive to spark discharge. This effort, funded by the Department of Homeland Security (DHS), ultimately will put the issues of safe handling of these materials in perspective with standard military explosives. The study is adding SSST testing results for a broad suite of different HMEs to the literature. Ultimately the study has the potential to suggest new guidelines and methods and possibly establish the SSST testing accuracies needed to develop safe handling practices for HMEs. Each participating testing laboratory uses identical test materials and preparation methods wherever possible. Note, however, the test procedures differ among the laboratories. The results are compared among the laboratories and then compared to historical data from various sources. The testing performers involved for the KClO<sub>4sub>/carbon mixture are Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Indian Head Division, Naval Surface Warfare Center, (NSWC IHD), and Air Force Research Laboratory (AFRL/RXQL). These tests are conducted as a proficiency study in order to establish some consistency in test protocols, procedures, and experiments and to understand how to compare results when these testing variables cannot be made consistent.

  18. Heuristic reasoning

    CERN Document Server

    2015-01-01

    How can we advance knowledge? Which methods do we need in order to make new discoveries? How can we rationally evaluate, reconstruct and offer discoveries as a means of improving the ‘method’ of discovery itself? And how can we use findings about scientific discovery to boost funding policies, thus fostering a deeper impact of scientific discovery itself? The respective chapters in this book provide readers with answers to these questions. They focus on a set of issues that are essential to the development of types of reasoning for advancing knowledge, such as models for both revolutionary findings and paradigm shifts; ways of rationally addressing scientific disagreement, e.g. when a revolutionary discovery sparks considerable disagreement inside the scientific community; frameworks for both discovery and inference methods; and heuristics for economics and the social sciences.

  19. Effect of Fe{sub 2}O{sub 3} addition in Yttria-stabilized zirconia properties; Efeito da adicao de Fe{sub 2}O{sub 3} nas propriedades da zirconia estabilizada com itria

    Energy Technology Data Exchange (ETDEWEB)

    Mendes, Pedro de Freitas Castro; Elias, Carlos Nelson; Santos, Heraldo Elias Salomao dos, E-mail: elias@ime.eb.br [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Secao de Engenharia Mecanica e de Materiais. Laboratorio de Biomateriais

    2017-04-15

    The zirconium oxide (ZrO{sub 2}) polycrystalline partially stabilized by yttrium oxide (Y{sub 2}O{sub 3}) at 3mol%, 3Y-TZP, has its use been increased as a biomaterial. However, as dental prosthetics, its indication is still limited because of its white color and high opacity. Seeking improvements regarding aesthetics without compromising its functional performance, oxides such as iron oxide (Fe{sub 2}O{sub 3}) has been added to the microstructure of zirconia in order to provide a yellow-brownish color similar to natural teeth. This study evaluated the effect of adding Fe{sub 2}O{sub 3} on the microstructure and mechanical and optical properties of 3Y-TZP. Five groups were investigated containing different concentrations of Fe{sub 2}O{sub 3}. Firstly, a chemical characterization of each group was carried out through X-ray fluorescence test (XRF). Microstructural characterization was performed by density and average grain size measurements. Mechanical properties were evaluated by performing hardness and four points flexural strength tests. Quantitative analysis of phase transformation was done using the Rietveld method, for each group submitted to the test of X-ray diffraction (XRD). Fractography by SEM analysis were also made on the fracture surface of the samples from tensile test. The results showed that the Fe{sub 2}O{sub 3} addition influenced the phase transformation process, and proportionally increased the samples hardness and flexural strength when their concentrations varied from 0.02% to 0.17% of the total weight. Above this range, the samples showed losses in their mechanical performance. The Fe{sub 2}O{sub 3} additions showed no significant changes in the density and average grain size of 3Y-TZP. (author)

  20. Motivated Reasoning, Political Information, and Information Literacy Education

    Science.gov (United States)

    Lenker, Mark

    2016-01-01

    Research in psychology and political science has identified motivated reasoning as a set of biases that inhibit a person's ability to process political information objectively. This research has important implications for the information literacy movement's aims of fostering lifelong learning and informed citizenship. This essay argues that…