High Energy Radical Chemistry Formation of HCN- rich Atmospheres on early Earth

Czech Academy of Sciences Publication Activity Database

Ferus, Martin; Kubelík, Petr; Knížek, Antonín; Pastorek, Adam; Sutherland, J.D.; Civiš, Svatopluk

2017-01-01

Roč. 7, č. 1 (2017), č. článku 6275. ISSN 2045-2322 R&D Projects: GA ČR GA17-05076S; GA MŠk(CZ) LM2015083; GA MŠk LG15013 Grant - others:Akademie věd - GA AV ČR(CZ) R200401521 Institutional support: RVO:61388955 Keywords : high-power laser * transform emission-spectroscopy * induced dielectric-breakdown * prebiotic organic-synthesis * nucleobase formation Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 4.259, year: 2016

Data-Driven Exercises for Chemistry: A New Digital Collection

Science.gov (United States)

Grubbs, W. Tandy

2007-01-01

The analysis presents a new digital collection for various data-driven exercises that are used for teaching chemistry to the students. Such methods are expected to help the students to think in a more scientific manner.

High-Energy Chemistry of Formamide: A Simpler Way for Nucleobase Formation

Czech Academy of Sciences Publication Activity Database

Ferus, Martin; Michalčíková, Regina; Shestivska, Violetta; Šponer, Jiří; Šponer, Judit E.; Civiš, Svatopluk

2014-01-01

Roč. 118, č. 4 (2014), s. 719-736 ISSN 1089-5639 R&D Projects: GA ČR GAP208/10/2302; GA MŠk LM2010014 Institutional support: RVO:61388955 ; RVO:68081707 Keywords : HIGH-POWER LASER * TRANSFORM EMISSION-SPECTROSCOPY * INDUCED DIELECTRIC-BREAKDOWN Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.693, year: 2014

COLLECTIVE ACTION AND COLLECTIVE SCHEME IN THE MOBILIZATION OF LEARNING CHEMISTRY ACCORDING TO VERGNAUD’S THEORY OF CONCEPTUAL FIELDS

Directory of Open Access Journals (Sweden)

Lucia Machado de Andrade

2017-10-01

Full Text Available This research’s aim was to analyze the mobilization in learning chemistry promoted by the collective action of three entrant students in higher education courses, in a college located in Santo André. For such, cognitive indicators mobilized by them while living individual and group situations on water’s boiling point, using Screencast video lessons as a motivational strategy, were analyzed. The fulfilment of these situations’ corresponding tasks was filmed, and the recordings were transcribed and analyzed with the help from the Transana software. The indicators used for the Discursive Textual Analysis were created by associating Vicente Talanquer’s Chemistry Knowledge Space to Gérard Vergnaud’s Theory of Conceptual Fields. The results displayed higher quantity and better quality to the indicators in situations with collective character, to the detriment to the ones with individual character. Thus, one might conclude that, under this research’s conditions, collective action, generated by a collective scheme, was capable of mobilizing the learning of chemistry.

Chemistry and climate change

International Nuclear Information System (INIS)

Bernier, Jean-Claude; Brasseur, Guy; Brechet, Yves; Candel, Sebastien; Cazenave, Anny; Courtillot, Vincent; Fontecave, Marc; Garnier, Emmanuel; Goebel, Philippe; Legrand, Jack; Legrand, Michel; Le Treut, Herve; Mauberger, Pascal; Dinh-Audouin, Minh-Thu; Olivier, Daniele; Rigny, Paul; Bigot, Bernard

2016-01-01

In its first part, this collective publication addresses the decennial and centuries-old variations of climate: perspectives and implications of climate change for the 21. century, questions remaining about the understanding of climate change from its sources to its modelling, extreme climate variations and societies during the last millennium. The contributions of the second part outline how chemistry is a tool to study climate change: ice chemistry as an archive of our past environment, observations and predictions on sea level rise, relationship between atmosphere chemistry and climate. The third set of contributions discusses the transformation of the energy system for a cleaner atmosphere and the management of the climate risk: the chemical processing of CO_2, actions of chemical companies to support the struggle against climate change, relationship between barrel price and renewable energies, relationship between grid complexity and green energy. The last part outlines the role chemistry can have to be able to do without fossil fuels: chemistry in front of challenges of transformation of the energy system, the use of micro-algae, the use of hydrogen as a vector of energy transition

Automatic Energy Schemes for High Performance Applications

Energy Technology Data Exchange (ETDEWEB)

Sundriyal, Vaibhav [Iowa State Univ., Ames, IA (United States)

2013-01-01

Although high-performance computing traditionally focuses on the efficient execution of large-scale applications, both energy and power have become critical concerns when approaching exascale. Drastic increases in the power consumption of supercomputers affect significantly their operating costs and failure rates. In modern microprocessor architectures, equipped with dynamic voltage and frequency scaling (DVFS) and CPU clock modulation (throttling), the power consumption may be controlled in software. Additionally, network interconnect, such as Infiniband, may be exploited to maximize energy savings while the application performance loss and frequency switching overheads must be carefully balanced. This work first studies two important collective communication operations, all-to-all and allgather and proposes energy saving strategies on the per-call basis. Next, it targets point-to-point communications to group them into phases and apply frequency scaling to them to save energy by exploiting the architectural and communication stalls. Finally, it proposes an automatic runtime system which combines both collective and point-to-point communications into phases, and applies throttling to them apart from DVFS to maximize energy savings. The experimental results are presented for NAS parallel benchmark problems as well as for the realistic parallel electronic structure calculations performed by the widely used quantum chemistry package GAMESS. Close to the maximum energy savings were obtained with a substantially low performance loss on the given platform.

XIX Mendeleev Congress on general and applied chemistry. Abstract book in 4 volumes. Volume 4. Chemistry aspects of modern energy and alternative energy resources. Chemistry of fossil and renewable hydrocarbon raw materials. Analytical chemistry: novel methods and devices for chemical research and analysis. Chemical education

International Nuclear Information System (INIS)

2011-01-01

The abstracts of the XIX Mendeleev Congress on general and applied chemistry held 25-30 September 2011 in Volgograd are presented. The program includes the Congress plenary and section reports, poster presentations, symposia and round tables on key areas of chemical science and technology, and chemical education. The work of the Congress was held the following sections: 1. Fundamental problems of chemical sciences; 2. Chemistry and technology of materials, including nanomaterials; 3. Physicochemical basis of metallurgical processes; 4. Current issues of chemical production, technical risk assessment; 5. Chemical aspects of modern power and alternative energy sources; 6. Chemistry of fossil and renewable hydrocarbons; 7. Analytical chemistry: new methods and instruments for chemical research and analysis; 8. Chemical education. Volume 4 includes abstracts of oral and poster presentations and presentations of correspondent participants of the sections: Chemistry aspects of modern energy and alternative energy resources; Chemistry of fossil and renewable hydrocarbon raw materials; Analytical chemistry: novel methods and devices for chemical research and analysis; Chemical education, and author index [ru

Advances in high temperature chemistry 1

CERN Document Server

Eyring, Leroy

2013-01-01

Advances in High Temperature Chemistry, Volume 1 describes the complexities and special and changing characteristics of high temperature chemistry. After providing a brief definition of high temperature chemistry, this nine-chapter book goes on describing the experiments and calculations of diatomic transition metal molecules, as well as the advances in applied wave mechanics that may contribute to an understanding of the bonding, structure, and spectra of the molecules of high temperature interest. The next chapter provides a summary of gaseous ternary compounds of the alkali metals used in

Symposium on high temperature and materials chemistry

International Nuclear Information System (INIS)

1989-10-01

This volume contains the written proceedings of the Symposium on High Temperature and Materials Chemistry held in Berkeley, California on October 24--25, 1989. The Symposium was sponsored by the Materials and Chemical Sciences Division of Lawrence Berkeley Laboratory and by the College of Chemistry of the University of California at Berkeley to discuss directions, trends, and accomplishments in the field of high temperature and materials chemistry. Its purpose was to provide a snapshot of high temperature and materials chemistry and, in so doing, to define status and directions

Symposium on high temperature and materials chemistry

Energy Technology Data Exchange (ETDEWEB)

1989-10-01

This volume contains the written proceedings of the Symposium on High Temperature and Materials Chemistry held in Berkeley, California on October 24--25, 1989. The Symposium was sponsored by the Materials and Chemical Sciences Division of Lawrence Berkeley Laboratory and by the College of Chemistry of the University of California at Berkeley to discuss directions, trends, and accomplishments in the field of high temperature and materials chemistry. Its purpose was to provide a snapshot of high temperature and materials chemistry and, in so doing, to define status and directions.

First-Year University Chemistry Textbooks' Misrepresentation of Gibbs Energy

Science.gov (United States)

Quilez, Juan

2012-01-01

This study analyzes the misrepresentation of Gibbs energy by college chemistry textbooks. The article reports the way first-year university chemistry textbooks handle the concepts of spontaneity and equilibrium. Problems with terminology are found; confusion arises in the meaning given to [delta]G, [delta][subscript r]G, [delta]G[degrees], and…

A High Five for ChemistryOpen.

Science.gov (United States)

Peralta, David; Ortúzar, Natalia

2016-02-01

Fabulous at five! When ChemistryOpen was launched in 2011, it was the first society-owned general chemistry journal to publish open-access articles exclusively. Five years down the line, it has featured excellent work in all fields of chemistry, leading to an impressive first full impact factor of 3.25. In this Editorial, read about how ChemistryOpen has grown over the past five years and made its mark as a high-quality open-access journal with impact.

Transverse momentum in high-energy nuclear collisions: Collective expansion

International Nuclear Information System (INIS)

Wang, X.; Hwa, R.C.

1987-01-01

Hadron production in the central region in high-energy nuclear collisions is investigated. The hydrodynamical expansion of a locally thermalized system is studied for both the cases with and without phase transition. The case with phase transition is considered by using a sound-velocity function c/sub s/(T) parametrized to fit the energy density determined in a lattice gauge calculation. The effect of a transverse rarefaction wave is included in the calculation of the temperature profile of the expanding fluid. The transverse-momentum distribution of hadrons is calculated by collecting all the hadrons produced when the hadron gas is cooled down to a freeze-out temperature at different times in the expansion. Fluctuation in initial temperature and radius is allowed due to variation in impact parameter. On the basis of a study of the thermalization process in the parton model we impose a constraint on the initial temperature and the thermalization time, the simultaneous variation of both of which gives rise to a relationship between the average transverse momentum and rapidity density. We have found that there is no so-called ''plateau'' region in that relationship. The implication on the diagnostics of a quark-gluon plasma is discussed

HMI scientific report - chemistry 1987

International Nuclear Information System (INIS)

1989-01-01

Results of the R and D activities of the Radiation Chemistry Department, Hahn-Meitner-Institut, are reported, primarily dealing with the following subjects: Interface processes and energy conversion, high-energy photochemistry and radiation chemistry as well as trace elements chemistry. A list of publications and lectures is added and gives a view on results obtained in research and development. (EF) [de

Technetium Chemistry in High-Level Waste

International Nuclear Information System (INIS)

Hess, Nancy J.

2006-01-01

Tc contamination is found within the DOE complex at those sites whose mission involved extraction of plutonium from irradiated uranium fuel or isotopic enrichment of uranium. At the Hanford Site, chemical separations and extraction processes generated large amounts of high level and transuranic wastes that are currently stored in underground tanks. The waste from these extraction processes is currently stored in underground High Level Waste (HLW) tanks. However, the chemistry of the HLW in any given tank is greatly complicated by repeated efforts to reduce volume and recover isotopes. These processes ultimately resulted in mixing of waste streams from different processes. As a result, the chemistry and the fate of Tc in HLW tanks are not well understood. This lack of understanding has been made evident in the failed efforts to leach Tc from sludge and to remove Tc from supernatants prior to immobilization. Although recent interest in Tc chemistry has shifted from pretreatment chemistry to waste residuals, both needs are served by a fundamental understanding of Tc chemistry

Computational Study of Nonequilibrium Chemistry in High Temperature Flows

Science.gov (United States)

Doraiswamy, Sriram

Recent experimental measurements in the reflected shock tunnel CUBRC LENS-I facility raise questions about our ability to correctly model the recombination processes in high enthalpy flows. In the carbon dioxide flow, the computed shock standoff distance over the Mars Science Laboratory (MSL) shape was less than half of the experimental result. For the oxygen flows, both pressure and heat transfer data on the double cone geometry were not correctly predicted. The objective of this work is to investigate possible reasons for these discrepancies. This process involves systematically addressing different factors that could possibly explain the differences. These factors include vibrational modeling, role of electronic states and chemistry-vibrational coupling in high enthalpy flows. A state-specific vibrational model for CO2, CO, O2 and O system is devised by taking into account the first few vibrational states of each species. All vibrational states with energies at or below 1 eV are included in the present work. Of the three modes of vibration in CO2 , the antisymmetric mode is considered separately from the symmetric stretching mode and the doubly degenerate bending modes. The symmetric and the bending modes are grouped together since the energy transfer rates between the two modes are very large due to Fermi resonance. The symmetric and bending modes are assumed to be in equilibrium with the translational and rotational modes. The kinetic rates for the vibrational-translation energy exchange reactions, and the intermolecular and intramolecular vibrational-vibrational energy exchange reactions are based on experimental data to the maximum extent possible. Extrapolation methods are employed when necessary. This vibrational model is then coupled with an axisymmetric computational fluid dynamics code to study the expansion of CO2 in a nozzle. The potential role of low lying electronic states is also investigated. Carbon dioxide has a single excited state just below

Advances in high temperature water chemistry and future issues

International Nuclear Information System (INIS)

Millett, P.J.

2005-01-01

This paper traces the development of advances in high temperature water chemistry with emphasis in the field of nuclear power. Many of the water chemistry technologies used in plants throughout the world today would not have been possible without the underlying scientific advances made in this field. In recent years, optimization of water chemistry has been accomplished by the availability of high temperature water chemistry codes such as MULTEQ. These tools have made the science of high temperature chemistry readily accessible for engineering purposes. The paper closes with a discussion of what additional scientific data and insights must be pursued in order to support the further development of water chemistry technologies for the nuclear industry. (orig.)

Chemistry, sun, energy and environment; Chimie, soleil, energie et environnement

Energy Technology Data Exchange (ETDEWEB)

Bouchy, M. [Ecole Nationale Superieure des Industries Chimiques (ENSIC), 54 - Villers-les-Nancy (France); Enea, O. [Poitiers Univ., 86 (France); Flamant, G. [IMP-Odeillo-CNRS (France)] (and others)

2000-07-01

This document provides the 35 papers presented at the 'Chemistry, Sun, Energy and Environment' meeting, held February 3-4, 2000 in Saint-Avold, France. The main studied topic was the use of solar radiation for water treatment, volatile organic compounds decomposition and in some thermochemical processes. These research subjects are tackled in a fundamental and practical point of view. (O.M.)

Non-thermally activated chemistry

International Nuclear Information System (INIS)

Stiller, W.

1987-01-01

The subject is covered under the following headings: state-of-the art of non-thermally activated chemical processes; basic phenomena in non-thermal chemistry including mechanochemistry, photochemistry, laser chemistry, electrochemistry, photo-electro chemistry, high-field chemistry, magneto chemistry, plasma chemistry, radiation chemistry, hot-atom chemistry, and positronium and muonium chemistry; elementary processes in non-thermal chemistry including nuclear chemistry, interactions of electromagnetic radiations, electrons and heavy particles with matter, ionic elementary processes, elementary processes with excited species, radicalic elementary processes, and energy-induced elementary processes on surfaces and interfaces; and comparative considerations. An appendix with historical data and a subject index is given. 44 figs., 41 tabs., and 544 refs

Characterization of secondary electron collection for energy recovery from high energy ions with a magnetic field

International Nuclear Information System (INIS)

Hagihara, Shota; Wada, Takayuki; Nakamoto, Satoshi; Takeno, Hiromasa; Yasaka, Yasuyoshi; Furuyama, Yuichi; Taniike, Akira

2015-01-01

A traveling wave direct energy converter (TWDEC) is expected to be used as an energy recovery device for fast protons produced during the D- 3 He nuclear fusion reaction. Some protons, however, are not fully decelerated and pass through the device. A secondary electron direct energy converter (SEDEC) was proposed as an additional device to recover the protons passing through a TWDEC. In our previous study, magnetic field was applied for efficient secondary electron (SE) collection, but the SEs were reflected close to the collector due to the magnetic mirror effect and the collection was degraded. Herein, a new arrangement of magnets is proposed to be set away from the collector, and experiments in various conditions are performed. An appropriate arrangement away from the collector resulted in the improvement of SE collection. (author)

Student Conceptions about Energy Transformations: Progression from General Chemistry to Biochemistry

Science.gov (United States)

Wolfson, Adele J.; Rowland, Susan L.; Lawrie, Gwendolyn A.; Wright, Anthony H.

2014-01-01

Students commencing studies in biochemistry must transfer and build on concepts they learned in chemistry and biology classes. It is well established, however, that students have difficulties in transferring critical concepts from general chemistry courses; one key concept is "energy." Most previous work on students' conception of energy…

Radiation chemistry of aqueous solutions of acetonitrile and propionitrile

International Nuclear Information System (INIS)

Shushtarian, M.J.

1975-01-01

The radiation chemistry of water and aqueous solutions is a branch of radiation chemistry dealing with chemical changes in water and aqueous solutions induced by high energy radiations. High energy radiations of interest in radiation chemistry are short-wave electromagnetic radiations (X- and γ-rays) and fast charged particles (α- and β-particles, electrons, deuterons and fission fragments). The energy of the particles and photons bringing about chemical reactions in the field of modern radiation chemistry is much higher than that of photons causing photochemical reactions

HMI scientific report - chemistry 1988

International Nuclear Information System (INIS)

1989-01-01

Results of the R and D activities are reported, dealing with the following subjects: Interface processes and energy conversion, high-energy photochemistry and radiation chemistry as well as trace elements chemistry. A list of publications and lectures is added and gives a view on results obtained in research and development. (EF) [de

A green chemistry lab course

International Nuclear Information System (INIS)

Rank, J.; Lenoir, D.; Bahadir, M.; Koning, B.

2006-01-01

The traditional course content of chemistry classes must change to achieve better awareness of the important issues of sustainability in chemistry within the next generation of professional chemists. To provide the necessary material for the organic chemistry teaching lab course, which is part of almost all study programs in chemistry, material was developed and collected (http://www.oc-praktikum.de/en) that allows students and teachers to assess reactions beyond the experimental set up, reaction mechanism and chemical yield. Additional parameters like atom economy of chemical transformations, energy efficiency, and questions of waste, renewable feed stocks, toxicity and ecotoxicity, as well as the safety measures for the chemicals used are discussed. (author)

Using high-frequency sampling to detect effects of atmospheric pollutants on stream chemistry

Science.gov (United States)

Stephen D. Sebestyen; James B. Shanley; Elizabeth W. Boyer

2009-01-01

We combined information from long-term (weekly over many years) and short-term (high-frequency during rainfall and snowmelt events) stream water sampling efforts to understand how atmospheric deposition affects stream chemistry. Water samples were collected at the Sleepers River Research Watershed, VT, a temperate upland forest site that receives elevated atmospheric...

Non-equilibrium plasma chemistry at high pressure and its applications

International Nuclear Information System (INIS)

Bai Xiyao; Zhang Zhitao; Bai Mindong; Zhu Qiaoying

2000-01-01

A review is presented of research and development of gas discharge and non-equilibrium plasma including, new ideas of non-equilibrium plasma at high gas pressure. With special technology, strong electric fields (>400 Td) can be achieved by which electrons are accelerated suddenly, becoming high energy electrons (> 10 eV) at high pressure. On impact with the electrons, the gas molecules dissociate into ions, atomic ions, atoms and free radicals, and new substances or molecules can be synthesized through custom design. Chemical reaction difficult to achieve by conventional method can be realized or accelerated. Non-equilibrium plasma chemistry at high pressure has wide application prospects

Energy Connections and Misconnections across Chemistry and Biology.

Science.gov (United States)

Kohn, Kathryn P; Underwood, Sonia M; Cooper, Melanie M

2018-01-01

Despite the number of university students who take courses in multiple science disciplines, little is known about how they connect concepts between disciplines. Energy is a concept that underlies all scientific phenomena and, as such, provides an appropriate context in which to investigate student connections and misconnections across disciplines. In this study, university students concurrently enrolled in introductory chemistry and biology were interviewed to explore their perceptions of the integration of energy both within and across the disciplines, and how they attempted to accommodate and reconcile different disciplinary approaches to energy, to inform future, interdisciplinary course reform. Findings suggest that, while students believed energy to be important to the scientific world and to the disciplines of biology and chemistry, the extent to which it was seen as central to success in their courses varied. Differences were also apparent in students' descriptions of the molecular-level mechanisms by which energy transfer occurs. These findings reveal a disconnect between how energy is understood and used in introductory science course work and uncovers opportunities to make stronger connections across the disciplines. We recommend that instructors engage in interdisciplinary conversations and consider the perspectives and goals of other disciplines when teaching introductory science courses. © 2018 K. P. Kohn 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).

Theoretical chemistry in Belgium a topical collection from theoretical chemistry accounts

CERN Document Server

Champagne, Benoît; De Proft, Frank; Leyssens, Tom

2014-01-01

Readers of this volume can take a tour around the research locations in Belgium which are active in theoretical and computational chemistry. Selected researchers from Belgium present research highlights of their work. Originally published in the journal Theoretical Chemistry Accounts, these outstanding contributions are now available in a hardcover print format. This volume will be of benefit in particular to those research groups and libraries that have chosen to have only electronic access to the journal. It also provides valuable content for all researchers in theoretical chemistry.

Students' Energy Understanding Across Biology, Chemistry, and Physics Contexts

Science.gov (United States)

Opitz, S. T.; Neumann, K.; Bernholt, S.; Harms, U.

2017-07-01

Energy is considered both as a disciplinary core idea and as a concept cutting across science disciplines. Most previous approaches studied progressing energy understanding in specific disciplinary contexts, while disregarding the relation of understanding across them. Hence, this study provides a systematic analysis of cross-disciplinary energy learning. On the basis of a cross-sectional study with n = 742 students from grades 6, 8, and 10, we analyze students' progression in understanding energy across biology, chemistry, and physics contexts. The study is guided by three hypothetical scenarios that describe how the connection between energy understanding in the three disciplinary contexts changes across grade levels. These scenarios are compared using confirmatory factor analysis (CFA). The results suggest that, from grade 6 to grade 10, energy understanding in the three disciplinary contexts is highly interrelated, thus indicating a parallel progression of energy understanding in the three disciplinary contexts. In our study, students from grade 6 onwards appeared to have few problems to apply one energy understanding across the three disciplinary contexts. These findings were unexpected, as previous research concluded that students likely face difficulties in connecting energy learning across disciplinary boundaries. Potential reasons for these results and the characteristics of the observed cross-disciplinary energy understanding are discussed in the light of earlier findings and implications for future research, and the teaching of energy as a core idea and a crosscutting concept are addressed.

AECL research programs in chemistry

International Nuclear Information System (INIS)

Crocker, I.H.; Eastwood, T.A.; Smith, D.R.; Stewart, R.B.; Tomlinson, M.; Torgerson, D.F.

1980-09-01

Fundamental or underlying research in chemistry is being done in AECL laboratories to further the understanding of processes involved in current nuclear energy systems and maintain an awareness of progress at the frontiers of chemical research so that new advances can be turned to advantage in future AECL endeavours. The report introduces the current research topics and describes them briefly under the following headings: radiation chemistry, isotope separation, high temperature solution chemistry, fuel reprocessing chemistry, and analytical chemistry. (auth)

Chemistry Division annual progress report for period ending January 31, 1984

Energy Technology Data Exchange (ETDEWEB)

1984-05-01

Progress is reported in the following fields: coal chemistry, aqueous chemistry at high temperatures and pressures, geochemistry, high-temperature chemistry and thermodynamics of structural materials, chemistry of transuranium elements and compounds, separations chemistry, elecrochemistry, catalysis, chemical physics, theoretical chemistry, nuclear waste chemistry, chemistry of hazardous chemicals, and thermal energy storage.

Critical Science Education in a Suburban High School Chemistry Class

Science.gov (United States)

Ashby, Patrick

To improve students' scientific literacy and their general perceptions of chemistry, I enacted critical chemistry education (CCE) in two "regular level" chemistry classes with a group of 25 students in a suburban, private high school as part of this study. CCE combined the efforts of critical science educators (Fusco & Calabrese Barton, 2001; Gilbert 2013) with the performance expectations of the Next Generation Science Standards (NGSS) (NGSS Lead States, 2013a) to critically transform the traditional chemistry curriculum at this setting. Essentially, CCE engages students in the critical exploration of socially situated chemistry content knowledge and requires them to demonstrate this knowledge through the practices of science. The purpose of this study was to gauge these students development of chemistry content knowledge, chemistry interest, and critical scientific literacy (CSL) as they engaged in CCE. CSL was a construct developed for this study that necessarily combined the National Research Center's (2012) definition of scientific literacy with a critical component. As such, CSL entailed demonstrating content knowledge through the practices of science as well as the ability to critically analyze the intersections between science content and socially relevant issues. A mixed methods, critical ethnographic approach framed the collection of data from open-ended questionnaires, focus group interviews, Likert surveys, pre- and post unit tests, and student artifacts. These data revealed three main findings: (1) students began to develop CSL in specific, significant ways working through the activities of CCE, (2) student participants of CCE developed a comparable level of chemistry content understanding to students who participated in a traditional chemistry curriculum, and (3) CCE developed a group of students' perceptions of interest in chemistry. In addition to being able to teach students discipline specific content knowledge, the implications of this study are

Collections for terminology in chemistry

International Nuclear Information System (INIS)

1974-08-01

This book describes terminology in chemistry, which is divided into seven chapters. The contents of this book are element name, names of an inorganic compound such as ion and radical and polyacid, an organic compound on general principle and names, general terminology 1 and 2, unit and description method on summary, unit and the symbol for unit, number and pH, Korean mark for people's name in chemistry, names of JUPAC organic compound of summary, hydrocarbons, fused polycyclic hydrocarbons, bridged hydrocarbons, cyclic hydrocarbons with side chains, terpenes hydrocarbons, fundamental heterocyclic systems and heterocyclic spiro compounds.

Sign me up! Determining motivation for high school chemistry students enrolling in a second year chemistry course

Science.gov (United States)

Camarena, Nilda N.

A sample of 108 Pre-AP Chemistry students in Texas participated in a study to determine motivational factors for enrolling in AP Chemistry and University Chemistry. The factors measured were academic attitude, perceptions of chemistry, confidence level in chemistry, and expectations/experiences in the chemistry class. Students completed two questionnaires, one at the beginning of the year and one at the end. Four high school campuses from two school districts in Texas participated. Two campuses were traditional high schools and two were smaller magnet schools. The results from this study are able to confirm that there are definite correlations between academic attitudes, perceptions, confidence level, and experiences and a student's plans to enroll in AP and University Chemistry. The type of school as well as the student's gender seemed to have an influence on a student's plan to enroll in a second year of chemistry.

Hydration energies and specific influence of oxo complexes and high coordination numbers on the predicted chemistry of superheavy elements

International Nuclear Information System (INIS)

Jorgensen, C.K.; Penneman, R.A.

1975-01-01

On the basis of an analysis of the known ionization energies of gaseous ions and aqua ions of the 3d, 4f, and 6d transition groups and the radius effects, the chemistry of the superheavy elements is predicted. The formation of aqua ion and oxo complexes in the elements with Z below 121 is considered. It is probable that the series from 123 to 140 constitute a close analogy to the lanthanides with Th-like chemistry. Above Z = 140 the elements will probably displace a transition group behavior. A brief comment is made on the analytical aspects to be expected. (U.S.)

Cosmic Chemistry: A Proactive Approach to Summer Science for High School Students

Science.gov (United States)

Parsley, Danette; Ristvey, John

2014-01-01

Though school is out for the summer, ninth- and tenth-grade students at Union Intermediate High School are burning off energy playing a game of tag on the soccer field. But that is not all they are doing. They are also synthesizing and applying key chemistry concepts they have just learned related to the conditions of the early solar system. They…

Didactical design based on sharing and jumping tasks for senior high school chemistry learning

Science.gov (United States)

Fatimah, I.; Hendayana, S.; Supriatna, A.

2018-05-01

The purpose of this research is to develop the didactical design of senior high school chemistry learning based on sharing and jumping tasks in shift equilibrium chemistry. Sharing tasks used to facilitate students slow learners with help by other students of fast learners so they engage in learning. While jumping tasks used to challenge fast learners students so they didn’t feel bored in learning. In developing the didactic design, teacher activity is not only to focus on students and learning materials but also on the relationship between students and learning materials. The results of the analysis teaching plan of shift equilibrium chemistry in attached Senior High School to Indonesia University of Education showed that the learning activities more focus on how the teacher teaches instead of how the process of students’ learning. The use of research method is didactical design research (DDR). Didactical design consisted of three steps i.e. (a) analysing didactical condition before learning, (b) analyzing metapedadidactical, and (c) analyzing retrospective. Data were collected by test, observations, interviews, documentation and recordings (audio and video).The result showed that the didactical design on shift equilibrium chemistry was valid.

Ninth international symposium on hot atom chemistry. Abstracts

International Nuclear Information System (INIS)

1977-01-01

Abstracts of the papers presented at the Symposium are compiled. The topics considered were chemical dynamics of high energy reactions, hot atom chemistry in organic compounds of tritium, nitrogen, oxygen, and halogens, theory and chemical dynamics of hot atom reactions as determined by beam studies, solid state reactions of recoil atoms and implanted ions, hot atom chemistry in energy-related research, hot atom chemistry in inorganic compounds of oxygen and tritium, hot positronium chemistry, applied hot atom chemistry in labelling, chemical effects of radioactive decay, decay-induced reactions and excitation labelling, physical methods in hot atom chemistry, and hot atom reactions in radiation and stratospheric chemistry

The Department of Energy's Atmospheric Chemistry Program: A critical review

International Nuclear Information System (INIS)

1991-01-01

In response to a request from the Department of Energy's (DOE) Office of Health and Environmental Research (OHER), the Committee on Atmospheric Chemistry has reviewed OHER's Atmospheric Chemistry Program (ACP). This report contains the committee's evaluation and critique arising from that review. The review process included a two-day symposium held at the National Academy of Sciences on September 25 and 26, 1990, that focused on presenting the ACP's current components, recent scientific accomplishments, and scientific plans. Following the symposium, committee members met in a one-day executive session to formulate and outline this report. In undertaking this review, OHER and ACP management requested that the committee attempt to answer several specific questions involving the program's technical capability and productivity, its leadership and organization, and its future direction. These questions are given in the Appendix. This report represents the committee's response to the questions posed in the Appendix. Chapter I explores the committee's view of the role that atmospheric chemistry could and should assume within the DOE and its prospective National Energy Strategy. Chapter 2 assesses the current ACP, Chapter 3 presents recommendations for revising and strengthening it, and Chapter 4 restates the committee's conclusions and recommendations

Collective Focusing of Intense Ion Beam Pulses for High-energy Density Physics Applications

International Nuclear Information System (INIS)

Dorf, Mikhail A.; Kaganovich, Igor D.; Startsev, Edward A.; Davidson, Ronald C.

2011-01-01

The collective focusing concept in which a weak magnetic lens provides strong focusing of an intense ion beam pulse carrying a neutralizing electron background is investigated by making use of advanced particle-in-cell simulations and reduced analytical models. The original analysis by Robertson Phys. Rev. Lett. 48, 149 (1982) is extended to the parameter regimes of particular importance for several high-energy density physics applications. The present paper investigates (1) the effects of non-neutral collective focusing in a moderately strong magnetic field; (2) the diamagnetic effects leading to suppression of the applied magnetic field due to the presence of the beam pulse; and (3) the influence of a finite-radius conducting wall surrounding the beam cross-section on beam neutralization. In addition, it is demonstrated that the use of the collective focusing lens can significantly simplify the technical realization of the final focusing of ion beam pulses in the Neutralized Drift Compression Experiment-I (NDCX-I), and the conceptual designs of possible experiments on NDCX-I are investigated by making use of advanced numerical simulations.

Beyond Solar Fuels: Renewable Energy-Driven Chemistry.

Science.gov (United States)

Lanzafame, Paola; Abate, Salvatare; Ampelli, Claudio; Genovese, Chiara; Passalacqua, Rosalba; Centi, Gabriele; Perathoner, Siglinda

2017-11-23

The future feasibility of decarbonized industrial chemical production based on the substitution of fossil feedstocks (FFs) with renewable energy (RE) sources is discussed. Indeed, the use of FFs as an energy source has the greatest impact on the greenhouse gas emissions of chemical production. This future scenario is indicated as "solar-driven" or "RE-driven" chemistry. Its possible implementation requires to go beyond the concept of solar fuels, in particular to address two key aspects: i) the use of RE-driven processes for the production of base raw materials, such as olefins, methanol, and ammonia, and ii) the development of novel RE-driven routes that simultaneously realize process and energy intensification, particularly in the direction of a significant reduction of the number of the process steps. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Device and method for enhanced collection and assay of chemicals with high surface area ceramic

Science.gov (United States)

Addleman, Raymond S.; Li, Xiaohong Shari; Chouyyok, Wilaiwan; Cinson, Anthony D.; Bays, John T.; Wallace, Krys

2016-02-16

A method and device for enhanced capture of target analytes is disclosed. This invention relates to collection of chemicals for separations and analysis. More specifically, this invention relates to a solid phase microextraction (SPME) device having better capability for chemical collection and analysis. This includes better physical stability, capacity for chemical collection, flexible surface chemistry and high affinity for target analyte.

Conflicts in Chemistry: The Case of Plastics, a Role-Playing Game for High School Chemistry Students

Science.gov (United States)

Cook, Deborah H.

2014-01-01

Conflicts in Chemistry: The Case of Plastics, an innovative role-playing activity for high school students, was developed by the Chemical Heritage Foundation to promote increased public understanding of chemistry. The pilot program included three high school teachers and their students at three different schools and documented implementation and…

Using Public Participation to Improve MELs Energy Data Collection

Energy Technology Data Exchange (ETDEWEB)

Cheung, Iris (Hoi Ying); Kloss, Margarita; Brown, Rich; Meier, Alan

2014-03-11

Miscellaneous Electric Loads (MELs) have proliferated in the last decade, and comprise an increasing share of building energy consumption. Because of the diversity of MELs and our lack of understanding about how people use them, large-scale data collection is needed to inform meaningful energy reduction strategies. Traditional methods of data collection, however, usually incur high labor and metering equipment expenses. As an alternative, this paper investigates the feasibility of crowdsourcing data collection to satisfy at least part of the data collection needs with acceptable accuracy. This study assessed the reliability and accuracy of crowdsourced data, by recruiting over 20 volunteers (from the 2012 Lawrence Berkeley Lab, Open House event) to test our crowdsourcing protocol. The protocol asked volunteers to perform the following tasks for three test products with increasing complexity - record power meter and product characteristics, identify all power settings available, and report the measured power. Based on our collected data and analysis, we concluded that volunteers performed reasonably well for devices with functionalities with which they are familiar, and might not produce highly accurate field measurements for complex devices. Accuracy will likely improve when participants are measuring the power used by devices in their home which they know how to operate, by providing more specific instructions including instructional videos. When integrated with existing programs such as the Home Energy Saver tool, crowdsourcing data collection from individual homeowners has the potential to generate a substantial amount of information about MELs energy use in homes.

An Investigation of the Relationships among 11th Grade Students' Attitudes toward Chemistry, Metacognition and Chemistry Achievement

OpenAIRE

KINGIR, Sevgi; AYDEMİR, Nurdane

2014-01-01

The purpose of this study was to investigate the relationships among 11th grade students' metacognition, chemistry achievement and attitudes toward chemistry. A total of 81 high school students at 11th grade participated in this study. Data were collected using Metacognitive Awareness Inventory and Attitude Scale toward Chemistry at the end of the second half of the academic year 2010â€"2011. Students' report card mean scores in chemistry course for that academic year were ...

Writing Chemistry Jingles as an Introductory Activity in a High School Chemistry Class

Science.gov (United States)

Heid, Peter F.

2011-01-01

Starting the school year in an introductory high school chemistry class can be a challenge. The topic and approach is new to the students; many of the early chapters in the texts can be a bit tedious; and for many students the activities are uninspiring. My goal in the first few weeks of school is to hook the students on chemistry by getting them…

High-energy chemistry of formamide: A unified mechanism of nucleobase formation

Czech Academy of Sciences Publication Activity Database

Ferus, M.; Nesvorný, D.; Šponer, J.; Kubelík, Petr; Michalčíková, R.; Shestivska, V.; Šponer, J.E.; Civiš, S.

2015-01-01

Roč. 112, č. 3 (2015), s. 657-662 ISSN 0027-8424 Institutional support: RVO:68378271 Keywords : origin of life * asteroid impact * biomolecules * LIDB Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 9.423, year: 2015

An Investigation of the Relationships among 11th Grade Students' Attitudes toward Chemistry, Metacognition and Chemistry Achievement

OpenAIRE

KINGIR, Sevgi; AYDEMİR, Nurdane

2012-01-01

The purpose of this study was to investigate the relationships among 11th grade students' metacognition, chemistry achievement and attitudes toward chemistry. A total of 81 high school students at 11th grade participated in this study. Data were collected using Metacognitive Awareness Inventory and Attitude Scale toward Chemistry at the end of the second half of the academic year 2010â€"2011. Students' report card mean scores in chemistry course for that academic year were used as an ind...

Lithium Ion Battery Chemistries from Renewable Energy Storage to Automotive and Back-up Power Applications

DEFF Research Database (Denmark)

Stan, Ana-Irina; Swierczynski, Maciej Jozef; Stroe, Daniel Ioan

2014-01-01

Lithium ion (Li-ion) batteries have been extensively used in consumer electronics because of their characteristics, such as high efficiency, long life, and high gravimetric and volumetric energy. In addition, Li-ion batteries are becoming the most attractive candidate as electrochemical storage...... systems for stationary applications, as well as power source for sustainable automotive and back-up power supply applications. This paper gives an overview of the Li-ion battery chemistries that are available at present in the market, and describes the three out of four main applications (except...... the consumers’ applications), grid support, automotive, and back-up power, for which the Li-ion batteries are suitable. Each of these applications has its own specifications and thus, the chemistry of the Li-ion battery should be chosen to fulfil the requirements of the corresponding application. Consequently...

Future in actinoids coordination chemistry

International Nuclear Information System (INIS)

Kitazawa, Takafumi

2006-01-01

Actinoids coordination chemistry is concerned with spent nuclear fuel reprocessing, specifically with solid-state chemistry of nuclear fuels, separation process with radioactive substances, and geological disposal of high-level radioactive substances. In the 21st century, accumulation of minor actinides, Np, Am, Cm, and others will be realized according with the present program of nuclear energy development. The present article briefly introduces general properties of actinide elements, followed by their coordination chemistry compared with rare earths coordination chemistry. Special facility needed to treat actinoids as well as their chemistry is briefly explained, together with the specific experimental apparatus such as X-ray Absorption Fine Structure (XAFS) and time-resolved laser-induced fluorescence spectrometry (TRLFS) with synchrotron radiation facilities. The effect of coordination with actinoids in the environment chemistry is important in underground disposal of high-level radioactive wastes. For theoretical analysis of the results with actinoids chemistry, relativistic calculation is needed. (S. Ohno)

Collection Development: Celebrating Chemistry, February 1, 2011

Science.gov (United States)

Hamm, Susannah

2011-01-01

A hundred years after Marie Curie received her Nobel Prize in Chemistry, this arm of science is pointing the way to a more sustainable future. Growing movements like green chemistry, which strives to create alternative and new chemical reactions that produce no harmful waste products, and molecular engineering hold great potential for industry,…

2nd Workshop on the Chemistry of Energy Conversion

CERN Document Server

2016-01-01

A sustainable energy future that does not rely on fossil fuels requires the advances of new materials design and development with efficient energy conversion. However, materials development is still at its infancy. There is an imperative to develop new energy conversion strategies. In Nature, plants harness sunlight and convert them into chemical energy. The ability to mimic Nature by combining synthetic nanoscopic and molecular components to produce chemical fuels is the Holy Grail to achieve sustainable energy production.​ The Institute of Advanced Studies (IAS) and the School of Physical and Mathematical Sciences (SPMS), NTU, are jointly organizing this workshop. We aim to create dialogues among scientists in the energy conversion field, with the ultimate goal of facilitating breakthroughs in materials design for energy conversion. It will also bring the expertise on Chemistry of Energy Conversion to the door steps of the materials research community in Singapore and also provide a platform for partic...

High temperature water chemistry monitoring

International Nuclear Information System (INIS)

Aaltonen, P.

1992-01-01

Almost all corrosion phenomena in nuclear power plants can be prevented or at least damped by water chemistry control or by the change of water chemistry control or by the change of water chemistry. Successful water chemistry control needs regular and continuous monitoring of such water chemistry parameters like dissolved oxygen content, pH, conductivity and impurity contents. Conventionally the monitoring is carried out at low pressures and temperatures, which method, however, has some shortcomings. Recently electrodes have been developed which enables the direct monitoring at operating pressures and temperatures. (author). 2 refs, 5 figs

Smart Cities Will Need Chemistry

Directory of Open Access Journals (Sweden)

Alexandru WOINAROSCHY

2016-06-01

Full Text Available A smart city is a sustainable and efficient urban centre that provides a high quality of life to its inhabitants through optimal management of its resources. Chemical industry has a key role to play in the sustainable evolution of the smart cities. Additionally, chemistry is at the heart of all modern industries, including electronics, information technology, biotechnology and nano-technology. Chemistry can make the smart cities project more sustainable, more energy efficient and more cost effective. There are six broad critical elements of any smart city: water management systems; infrastructure; transportation; energy; waste management and raw materials consumption. In all these elements chemistry and chemical engineering are deeply involved.

The status of safety in the public high school chemistry laboratories in Mississippi

Science.gov (United States)

Lacy, Sarah Louise Trotman

Since laboratory-based science courses have become an essential element of any science curriculum and are required by the Mississippi Department of Education for graduation, the chemistry laboratories in the public high schools in Mississippi must be safe. The purpose of this study was to determine: the safety characteristics of a high school chemistry laboratory; the perceived safety characteristics of the chemistry laboratories in public high schools in Mississippi; the basic safety knowledge of chemistry teachers in public high schools in Mississippi, where chemistry teachers in Mississippi gain knowledge about laboratory safety and instruction; if public high school chemistry laboratories in Mississippi adhere to recommended class size, laboratory floor space per student, safety education, safety equipment, and chemical storage; and the relationship between teacher knowledge of chemistry laboratory safety and the safety status of the laboratory in which they teach. The survey instrument was composed of three parts. Part I Teacher Knowledge consisted of 23 questions concerning high school chemistry laboratory safety. Part II Chemistry Laboratory Safety Information consisted of 40 items divided into four areas of interest concerning safety in high school chemistry laboratories. Part III Demographics consisted of 11 questions relating to teacher certification, experience, education, and safety training. The survey was mailed to a designated chemistry teacher in every public high school in Mississippi. The responses to Part I of the survey indicated that the majority of the teachers have a good understanding of knowledge about chemistry laboratory safety but need more instruction on the requirements for a safe high school chemistry laboratory. Less than 50% of the responding teachers thought they had received adequate preparation from their college classes to conduct a safe chemistry laboratory. According to the responses of the teachers, most of their high school

Fabrication and Characterization of Li-ion Electrodes for High-Power Energy Storage Devices

OpenAIRE

Lai, Chun-Han

2017-01-01

Renewable energy technologies have been a rapidly emerging option to meet future energy demand. However, their systems require stable, high-power storage devices to overcome fluctuating energy outputs for consistent distribution. Since traditional Li-ion batteries (LIB) are not considered to be capable of fast charging and discharging, we have to develop devices with new chemistry for high-power operation. This dissertation focuses on the development of supercapacitors and high-rate batteries...

Chemistry of high temperature superconductors

CERN Document Server

1991-01-01

This review volume contains the most up-to-date articles on the chemical aspects of high temperature oxide superconductors. These articles are written by some of the leading scientists in the field and includes a comprehensive list of references. This is an essential volume for researchers working in the fields of ceramics, materials science and chemistry.

Developing A Renewable Energy Awareness Scale For Pre-service Chemistry Teachers

Directory of Open Access Journals (Sweden)

Soner YAVUZ

2006-01-01

Full Text Available Developing A Renewable Energy Awareness Scale For Pre-service Chemistry Teachers Inci MORGIL Nilgün SECKEN A. Seda YUCEL Ozge OZYALCIN OSKAY Soner YAVUZ and Evrim URAL Hacettepe University, Faculty of Education, Department of Chemistry Education, 06800 Beytepe, Ankara, TURKEY ABSTRACT In times when human beings used to live in a natural environment, their needs were also provided by natural resources. With the increases in population in time, human beings started to look for new resources willing to get “the more” and “the fastest”. Just like the invention of steam, firstly, they increased the density of the resources and produced “more” energy. However, instead of working on the density of water, which spreads with the solar energy, they chose an easier way, which was fuel that produced more energy when burnt. Unfortunately, the damages these fuel products create in the atmosphere and environment shaded their benefits. It did not take so long for the earth to run out of energy resources and to threaten environmental and human health. As a result of that, new energy resources were started to be sought and the studies enlightened the concepts of sustainable, renewable energy. Renewable energy is defined as “the energy source, which continues its existence for the following days within the evolution of nature”. Educators pointed out a need in students for gaining consciousness on renewable energy resources. In the light of the importance of renewable and sustainable energy, a “Renewable Energy Awareness Scale” that questioned to what extent the individuals were aware of renewable energy was developed. The Renewable Energy Awareness Scale, which consisted of 50 items, was administered as a pilot study. The factor analysis concluded with a scale of 39 items with a reliability coefficient of 0.944 was developed.

High-energy chemistry of formamide: A unified mechanism of nucleobase formation

Czech Academy of Sciences Publication Activity Database

Ferus, Martin; Nesvorný, D.; Šponer, Jiří; Kubelík, Petr; Michalčíková, Regina; Shestivska, Violetta; Šponer, Judit E.; Civiš, Svatopluk

2015-01-01

Roč. 112, č. 3 (2015), s. 657-662 ISSN 0027-8424 R&D Projects: GA MŠk LM2010014; GA ČR(CZ) GA14-12010S Institutional support: RVO:61388955 ; RVO:68081707 Keywords : origin of life * asteroid impact * biomolecules Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 9.423, year: 2015

Theoretical aspects of some collective instabilities in high-energy particle storage rings

International Nuclear Information System (INIS)

Ruggiero, F.

1986-01-01

After an introduction to single-particle dynamics, based on a unified Hamiltonian treatment of betatron and synchrotron oscillations, we consider two examples of collective instabilities which can limit the performances of high-energy storage rings: the transverse mode coupling instability, due to wake fields, and the incoherent beam-beam instability. Special emphasis is placed on the localization of the interactions between particles and surrounding structures, such as the accelerating RF cavities. We derive an exact invariant for the linearized synchrotron motion and, starting from the Vlasov equation, we discuss the coherent synchro-betatron resonances caused by localized impedance. Under suitable assumptions, we show that the effect of the beam-beam kicks in electron-positron machines can be described by new diffusive terms in a ''renormalized'' Fokker-Planck equation and is therefore equivalent to an additional source of noise for the betatron oscillations. (orig.)

Material chemistry challenges in vitrification of high level radioactive waste

International Nuclear Information System (INIS)

Kaushik, C.P.

2008-01-01

Full text: Nuclear technology with an affective environmental management plan and focused attention on safety measures is a much cleaner source of electricity generation as compared to other sources. With this perspective, India has undertaken nuclear energy program to share substantial part of future need of power. Safe containment and isolation of nuclear waste from human environment is an indispensable part of this programme. Majority of radioactivity in the entire nuclear fuel cycle is high level radioactive liquid waste (HLW), which is getting generated during reprocessing of spent nuclear fuels. A three stage strategy for management of HLW has been adopted in India. This involves (i) immobilization of waste oxides in stable and inert solid matrices, (ii) interim retrievable storage of the conditioned waste product under continuous cooling and (iii) disposal in deep geological formation. Borosilicate glass matrix has been adopted in India for immobilization of HLW. Material issue are very important during the entire process of waste immobilization. Performance of the materials used in nuclear waste management determines its safety/hazards. Material chemistry therefore has a significant bearing on immobilization science and its technological development for management of HLW. The choice of suitable waste form to deploy for nuclear waste immobilization is difficult decision and the durability of the conditioned product is not the sole criterion. In any immobilization process, where radioactive materials are involved, the process and operational conditions play an important role in final selection of a suitable glass formulation. In remotely operated vitrification process, study of chemistry of materials like glass, melter, materials of construction of other equipment under high temperature and hostile corrosive condition assume significance for safe and un-interrupted vitrification of radioactive to ensure its isolation waste from human environment. The present

A context based approach using Green Chemistry/Bio-remediation principles to enhance interest and learning of organic chemistry in a high school AP chemistry classroom

Science.gov (United States)

Miller, Tricia

The ability of our planet to sustain life and heal itself is not as predictable as it used to be. Our need for educated future scientists who know what our planet needs, and can passionately apply that knowledge to find solutions should be at the heart of science education today. This study of learning organic chemistry through the lens of the environmental problem "What should be done with our food scraps?" explores student interest, and mastery of certain concepts in organic chemistry. This Green Chemistry/ Bio-remediation context-based teaching approach utilizes the Nature MillRTM, which is an indoor food waste composting machine, to learn about organic chemistry, and how this relates to landfill reduction possibilities, and resource production. During this unit students collected food waste from their cafeteria, and used the Nature MillRTM to convert food waste into compost. The use of these hands on activities, and group discussions in a context-based environment enhanced their interest in organic chemistry, and paper chromatography. According to a one-tailed paired T-test, the result show that this context-based approach is a significant way to increase both student interest and mastery of the content.

High Energy Batteries for Hybrid Buses

Energy Technology Data Exchange (ETDEWEB)

Bruce Lu

2010-12-31

EnerDel batteries have already been employed successfully for electric vehicle (EV) applications. Compared to EV applications, hybrid electric vehicle (HEV) bus applications may be less stressful, but are still quite demanding, especially compared to battery applications for consumer products. This program evaluated EnerDel cell and pack system technologies with three different chemistries using real world HEV-Bus drive cycles recorded in three markets covering cold, hot, and mild climates. Cells were designed, developed, and fabricated using each of the following three chemistries: (1) Lithium nickel manganese cobalt oxide (NMC) - hard carbon (HC); (2) Lithium manganese oxide (LMO) - HC; and (3) LMO - lithium titanium oxide (LTO) cells. For each cell chemistry, battery pack systems integrated with an EnerDel battery management system (BMS) were successfully constructed with the following features: real time current monitoring, cell and pack voltage monitoring, cell and pack temperature monitoring, pack state of charge (SOC) reporting, cell balancing, and over voltage protection. These features are all necessary functions for real-world HEV-Bus applications. Drive cycle test data was collected for each of the three cell chemistries using real world drive profiles under hot, mild, and cold climate conditions representing cities like Houston, Seattle, and Minneapolis, respectively. We successfully tested the battery packs using real-world HEV-Bus drive profiles under these various climate conditions. The NMC-HC and LMO-HC based packs successfully completed the drive cycles, while the LMO-LTO based pack did not finish the preliminary testing for the drive cycles. It was concluded that the LMO-HC chemistry is optimal for the hot or mild climates, while the NMC-HC chemistry is optimal for the cold climate. In summary, the objectives were successfully accomplished at the conclusion of the project. This program provided technical data to DOE and the public for assessing

A topological screening heuristic for low-energy, high-index surfaces

Science.gov (United States)

Sun, Wenhao; Ceder, Gerbrand

2018-03-01

Robust ab initio investigations of nanoparticle surface properties require a method to identify candidate low-energy surface facets a priori. By assuming that low-energy surfaces are planes with high atomic density, we devise an efficient algorithm to screen for low-energy surface orientations, even if they have high (hkl) miller indices. We successfully predict the observed low-energy, high-index { 10 12 bar } and { 10 1 bar 4 } surfaces of hematite α-Fe2O3, the {311} surfaces of cuprite Cu2O, and the {112} surfaces of anatase TiO2. We further tabulate candidate low-energy surface orientations for nine of the most common binary oxide structures. Screened surfaces are found to be generally applicable across isostructural compounds with varying chemistries, although relative surface energies between facets may vary based on the preferred coordination of the surface atoms.

Scientific projection paper for radiation chemistry

International Nuclear Information System (INIS)

Simic, M.G.

1980-01-01

Together with radiation physics, an understanding of radiation chemistry is necessary for full appreciation of biological effects of high and low energy radiations, and for the development of prophylactic, therapeutic and potentiating methods and techniques in biological organisms. Areas covered in some detail in this report include: the early chemical events involved in the deposition of radiation energy; the kinetics of free radical and excited state reactions; the application of radiation chemistry to radiation biology; and the availability of instrumentation

Sparingly Solvating Electrolytes for High Energy Density Lithium-Sulfur Batteries

Energy Technology Data Exchange (ETDEWEB)

Cheng, Lei; Curtiss, Larry A.; Zavadil, Kevin R.; Gewirth, Andrew A.; Shao, Yuyan; Gallagher, Kevin

2016-07-11

Moving to lighter and less expensive battery chemistries compared to lithium-ion requires the control of energy storage mechanisms based on chemical transformations rather than intercalation. Lithium sulfur (Li/S) has tremendous theoretical specific energy, but contemporary approaches to control this solution-mediated, precipitation-dissolution chemistry requires using large excesses of electrolyte to fully solubilize the polysulfide intermediate. Achieving reversible electrochemistry under lean electrolyte operation is the only path for Li/S to move beyond niche applications to potentially transformational performance. An emerging topic for Li/S research is the use of sparingly solvating electrolytes and the creation of design rules for discovering new electrolyte systems that fundamentally decouple electrolyte volume from reaction mechanism. This perspective presents an outlook for sparingly solvating electrolytes as the key path forward for longer-lived, high-energy density Li/S batteries including an overview of this promising new concept and some strategies for accomplishing it.

A high-energy-density redox flow battery based on zinc/polyhalide chemistry.

Science.gov (United States)

Zhang, Liqun; Lai, Qinzhi; Zhang, Jianlu; Zhang, Huamin

2012-05-01

Zn and the Art of Battery Development: A zinc/polyhalide redox flow battery employs Br(-) /ClBr(2-) and Zn/Zn(2+) redox couples in its positive and negative half-cells, respectively. The performance of the battery is evaluated by charge-discharge cycling tests and reveals a high energy efficiency of 81%, based on a Coulombic efficiency of 96% and voltage efficiency of 84%. The new battery technology can provide high performance and energy density at an acceptable cost. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Treatment of Electronic Energy Level Transition and Ionization Following the Particle-Based Chemistry Model

Science.gov (United States)

Liechty, Derek S.; Lewis, Mark

2010-01-01

A new method of treating electronic energy level transitions as well as linking ionization to electronic energy levels is proposed following the particle-based chemistry model of Bird. Although the use of electronic energy levels and ionization reactions in DSMC are not new ideas, the current method of selecting what level to transition to, how to reproduce transition rates, and the linking of the electronic energy levels to ionization are, to the author s knowledge, novel concepts. The resulting equilibrium temperatures are shown to remain constant, and the electronic energy level distributions are shown to reproduce the Boltzmann distribution. The electronic energy level transition rates and ionization rates due to electron impacts are shown to reproduce theoretical and measured rates. The rates due to heavy particle impacts, while not as favorable as the electron impact rates, compare favorably to values from the literature. Thus, these new extensions to the particle-based chemistry model of Bird provide an accurate method for predicting electronic energy level transition and ionization rates in gases.

Using Public Participation to Improve MELs Energy Data Collection

Energy Technology Data Exchange (ETDEWEB)

Kloss, Margarita; Cheung, Iris [Hoi; Brown, Richard; Meier, Alan

2014-08-11

Miscellaneous and electronic loads (MELs) comprise an increasing share of building energy consumption. Large-scale data collection is needed to inform meaningful energy reduction strategies because of the diversity of MELs and our lack of understanding about how people use them. Traditional methods of data collection, however, usually incur high labor and metering equipment expenses. As an alternative, this paper investigates the feasibility of crowdsourcing data collection to satisfy at least part of the data collection needs with acceptable accuracy. We assessed the reliability and accuracy of crowd-sourced data by recruiting 18 volunteers and testing our crowdsourcing protocol. The protocol asked volunteers to perform measurement tasks for three MELs devices of increasing complexity 1) record power meter and MELs product characteristics, 2) identify and measure all power modes available, and 3) report the measured power. Volunteers performed reasonably well for devices with functionalities with which they were familiar, but many could not correctly identify all available power modes in complex devices. Accuracy may improve when participants measure the power used by familiar devices in their home, or by providing more specific instructions, e.g. videos. Furthermore, crowdsourcing data collection from individual homeowners has the potential to generate valuable information about MELs energy use in homes when integrated with existing programs such as Home Energy Saver and Building America.

Surveys of research in the Chemistry Division, Argonne National Laboratory

Energy Technology Data Exchange (ETDEWEB)

Grazis, B.M. [ed.

1992-11-01

Research reports are presented on reactive intermediates in condensed phase (radiation chemistry, photochemistry), electron transfer and energy conversion, photosynthesis and solar energy conversion, metal cluster chemistry, chemical dynamics in gas phase, photoionization-photoelectrons, characterization and reactivity of coal and coal macerals, premium coal sample program, chemical separations, heavy elements coordination chemistry, heavy elements photophysics/photochemistry, f-electron interactions, radiation chemistry of high-level wastes (gas generation in waste tanks), ultrafast molecular electronic devices, and nuclear medicine. Separate abstracts have been prepared. Accelerator activites and computer system/network services are also reported.

Surveys of research in the Chemistry Division, Argonne National Laboratory

Energy Technology Data Exchange (ETDEWEB)

Grazis, B.M. (ed.)

1992-01-01

Research reports are presented on reactive intermediates in condensed phase (radiation chemistry, photochemistry), electron transfer and energy conversion, photosynthesis and solar energy conversion, metal cluster chemistry, chemical dynamics in gas phase, photoionization-photoelectrons, characterization and reactivity of coal and coal macerals, premium coal sample program, chemical separations, heavy elements coordination chemistry, heavy elements photophysics/photochemistry, f-electron interactions, radiation chemistry of high-level wastes (gas generation in waste tanks), ultrafast molecular electronic devices, and nuclear medicine. Separate abstracts have been prepared. Accelerator activites and computer system/network services are also reported.

Charge collection characteristics of a super-thin diamond membrane detector measured with high-energy heavy ions

International Nuclear Information System (INIS)

Iwamoto, N.; Makino, T.; Onoda, S.; Ohshima, T.; Kamiya, T.; Kada, W.; Skukan, N.; Grilj, V.; Jaksic, M.; Pomorski, M.

2014-01-01

A transmission particle detector based on a super-thin diamond membrane film which can also be used simultaneously as a vacuum window for ion beam extraction has been developed. Charge collection characteristics of a μ-thick diamond membrane detector for high-energy heavy ions including 75 MeV Ne, 150 MeV Ar, 322 MeV Kr, and 454 MeV Xe have been investigated for the first time. Charge collection signals under single particle flux from the thin part are stable and are well distinguishable from background signals. This behavior suggests that the diamond membrane detector could be used for counting single ions. On the other hand, charge collection efficiency is found to decrease with increasing of charge generated in the diamond membrane detector. This suggests that the pulse height defect, which has been previously reported for Si and SiC detectors, also occurs in the diamond membrane detector. (authors)

Determination of validity and reliability of performance assessments tasks developed for selected topics in high school chemistry

Science.gov (United States)

Zichittella, Gail Eberhardt

The primary purpose of this study was to validate performance assessments, which can be used as teaching and assessment instruments in high school science classrooms. This study evaluated the classroom usability of these performance instruments and establishes the interrater reliability of the scoring rubrics when used by classroom teachers. The assessment instruments were designed to represent two levels of scientific inquiry. The high level of inquiry tasks are relatively unstructured in terms of student directions; the low inquiry tasks provided more structure for the student. The tasks cover two content topics studied in chemistry (scientific observation and density). Students from a variety of Western New York school districts who were enrolled in chemistry classes and other science courses were involved in completion of the tasks at the two levels of inquiry. The chemistry students completed the NYS Regents Examination in Chemistry. Their classroom teachers were interviewed and completed a questionnaire to aid in the establishment their epistemological view on the inclusion of inquiry based learning in the science classroom. Data showed that the performance assessment tasks were reliable, valid and helpful for obtaining a more complete picture of the students' scientific understanding. The teacher participants reported no difficulty with the usability of the task in the high school chemistry setting. Collected data gave no evidence of gender bias with reference to the performance tasks or the NYS Regents Chemistry Examination. Additionally, it was shown that the instructors' classroom practices do have an effect upon the students' achievement on the performance tasks and the NYS Regents examination. Data also showed that achievement on the performance tasks was influenced by the number of years of science instruction students had received.

Modeling of the chemistry in oxidation flow reactors with high initial NO

Science.gov (United States)

Peng, Zhe; Jimenez, Jose L.

2017-10-01

Oxidation flow reactors (OFRs) are increasingly employed in atmospheric chemistry research because of their high efficiency of OH radical production from low-pressure Hg lamp emissions at both 185 and 254 nm (OFR185) or 254 nm only (OFR254). OFRs have been thought to be limited to studying low-NO chemistry (in which peroxy radicals (RO2) react preferentially with HO2) because NO is very rapidly oxidized by the high concentrations of O3, HO2, and OH in OFRs. However, many groups are performing experiments by aging combustion exhaust with high NO levels or adding NO in the hopes of simulating high-NO chemistry (in which RO2 + NO dominates). This work systematically explores the chemistry in OFRs with high initial NO. Using box modeling, we investigate the interconversion of N-containing species and the uncertainties due to kinetic parameters. Simple initial injection of NO in OFR185 can result in more RO2 reacted with NO than with HO2 and minor non-tropospheric photolysis, but only under a very narrow set of conditions (high water mixing ratio, low UV intensity, low external OH reactivity (OHRext), and initial NO concentration (NOin) of tens to hundreds of ppb) that account for a very small fraction of the input parameter space. These conditions are generally far away from experimental conditions of published OFR studies with high initial NO. In particular, studies of aerosol formation from vehicle emissions in OFRs often used OHRext and NOin several orders of magnitude higher. Due to extremely high OHRext and NOin, some studies may have resulted in substantial non-tropospheric photolysis, strong delay to RO2 chemistry due to peroxynitrate formation, VOC reactions with NO3 dominating over those with OH, and faster reactions of OH-aromatic adducts with NO2 than those with O2, all of which are irrelevant to ambient VOC photooxidation chemistry. Some of the negative effects are the worst for alkene and aromatic precursors. To avoid undesired chemistry, vehicle emissions

From hot atom chemistry to epithermal chemistry

International Nuclear Information System (INIS)

Roessler, K.

2004-01-01

The rise and fall of hot atom chemistry (HAC) over the years from 1934 to 2004 is reviewed. Several applications are discussed, in particular to astrophysics and the interaction of energetic ions and atoms in space. Epithermal chemistry (ETC) is proposed to substitute the old name, since it better fits the energy range as well as the non-thermal and non-equilibrium character of the reactions. ETC also avoids the strong connexion of HAC to nuclear chemistry and stands for the opening of the field to physical chemistry and astrophysics. (orig.)

Strengthening High School Chemistry Education through Teacher Outreach Programs: A Workshop Summary to the Chemical Sciences Roundtable

Science.gov (United States)

Olson, Steve

2009-01-01

A strong chemical workforce in the United States will be essential to the ability to address many issues of societal concern in the future, including demand for renewable energy, more advanced materials, and more sophisticated pharmaceuticals. High school chemistry teachers have a critical role to play in engaging and supporting the chemical…

Storying energy consumption: Collective video storytelling in energy efficiency social marketing.

Science.gov (United States)

Gordon, Ross; Waitt, Gordon; Cooper, Paul; Butler, Katherine

2018-05-01

Despite calls for more socio-technical research on energy, there is little practical advice to how narratives collected through qualitative research may be melded with technical knowledge from the physical sciences such as engineering and then applied in energy efficiency social action strategies. This is despite established knowledge in the environmental management literature about domestic energy use regarding the utility of social practice theory and narrative framings that socialise everyday consumption. Storytelling is positioned in this paper both as a focus for socio-technical energy research, and as one potential practical tool that can arguably enhance energy efficiency interventions. We draw upon the literature on everyday social practices, and storytelling, to present our framework called 'collective video storytelling' that combines scientific and lay knowledge about domestic energy use to offer a practical tool for energy efficiency management. Collective video storytelling is discussed in the context of Energy+Illawarra, a 3-year cross-disciplinary collaboration between social marketers, human geographers, and engineers to target energy behavioural change within older low-income households in regional NSW, Australia. Copyright © 2018 Elsevier Ltd. All rights reserved.

Basic radiation chemistry for the ionising energy treatment of food

International Nuclear Information System (INIS)

Moore, P.W.

1985-01-01

Before we can understand the chemistry involved in the irradiation of complex substances such as food we need to have some appreciation of the reactions involved and the products formed when ionising energy interacts with the simple substances such as water and dilute solutions. Reactions involving hydrated electrons, hydrogen atoms and hydroxyl radicals are examined and methods for minimising radiolytic effects in foods are discussed

The low energy (140 MeV) chemistry facility at the 500 MeV electron accelerator MEA at Amsterdam

International Nuclear Information System (INIS)

Brinkman, G.A.; Kapteyn, J.C.; Louwrier, P.W.F.; Lindner, L.; Peelen, B.; Polak, P.; Schimmel, A.; Stock, F.R.; Veenboer, J.T.; Visser, J.

1980-01-01

The facility includes the Low Energy Chemistry (LECH) hall equipped with a beam-line for pulse-radiolysis and a second one for the production of radioisotopes and for experiments with electron-free photon beams. It also includes the Low Energy Laboratory (LELAB) containing two chemistry laboratories and a control room. These facilities are also available to outside research groups. (orig./HP)

Collective and single-particle states at high excitation energy

International Nuclear Information System (INIS)

Van den Berg, A.M.; Van der Molen, H.K.T.; Harakeh, M.N.; Akimune, H.; Daito, I.; Fujimura, H.; Fujiwara, M.; Ihara, F.; Inomata, T.

2000-01-01

Complete text of publication follows. Damping of high-lying single-particle states was investigated by the study of proton decay from high-lying states in 91 Nb, populated by the 90 Zr(α,t) reaction with E α = 180 MeV. In addition to decay to the ground state of 90 Zr, semi-direct decay was observed to the low-lying (2 + and 3 - ) phonon states, confirming the conclusion from other experiments that these phonon states play an important role in the damping process of the single-particle states. Furthermore, the population and decay of Isobaric Analogue States of 91 Zr, which are located at an excitation energy of about 10 - 12 MeV in 91 Nb, has been studied in the same reaction. (author)

HEGEMONY OF CHEMISTRY LEARNING IN SENIOR HIGH SCHOOL IN BALI PROVINCE

Directory of Open Access Journals (Sweden)

I Gusti Lanang Wiaratma

2013-09-01

Full Text Available This study was intended to explain the power and the struggle of meaning behind the hegemony taking place in the management of Chemistry learning in the senior high schools developed to be the ones with International status “rintisan sekolah bertaraf internasional” (SMA RSBI in Bali. This could be observed from the management of Chemistry learning in SMA RSBI in Bali Province which tended to develop the students’ competence in the cognitive domain. This was done to make the students able to pass the national examination and to be the winners in academic competitions. The main theory used in the present study was the theory of hegemony, eclectically supported by several other theories. The method used in the present study was the qualitative method in which the sample was purposively determined. The data were collected through observation, interview, and documentation. The instrument used was an interview guide. The data were analyzed descriptively and qualitatively. The results of the study showed that the management of Chemistry learning was not optimal yet; it tended to be partially developed. The reason was that there was hegemony of the dominating class over the dominated class, hegemony of the teachers over the students. The students did not acquire maximum learning experience as prescribed in the curriculum. What was developed was the students’ competence in the cognitive domain. This took place due to the politics of image which maintained the status quo which tended to comodify education.

2010 Gordon Research Conference On Radiation Chemistry

International Nuclear Information System (INIS)

Orlando, Thomas

2010-01-01

The 2010 Gordon Conference on Radiation Chemistry will present cutting edge research regarding the study of radiation-induced chemical transformations. Radiation Chemistry or 'high energy' chemistry is primarily initiated by ionizing radiation: i.e. photons or particles with energy sufficient to create conduction band electrons and 'holes', excitons, ionic and neutral free radicals, highly excited states, and solvated electrons. These transients often interact or 'react' to form products vastly different than those produced under thermal equilibrium conditions. The non-equilibrium, non-thermal conditions driving radiation chemistry exist in plasmas, star-forming regions, the outer solar system, nuclear reactors, nuclear waste repositories, radiation-based medical/clinical treatment centers and in radiation/materials processing facilities. The 2010 conference has a strong interdisciplinary flavor with focus areas spanning (1) the fundamental physics and chemistry involved in ultrafast (atto/femtosecond) energy deposition events, (2) radiation-induced processes in biology (particularly spatially resolved studies), (3) radiation-induced modification of materials at the nanoscale and cosmic ray/x-ray mediated processes in planetary science/astrochemistry. While the conference concentrates on fundamental science, topical applied areas covered will also include nuclear power, materials/polymer processing, and clinical/radiation treatment in medicine. The Conference will bring together investigators at the forefront of their field, and will provide opportunities for junior scientists and graduate students to present work in poster format or as contributors to the Young Investigator session. The program and format provides excellent avenues to promote cross-disciplinary collaborations.

Development of Chemistry Triangle Oriented Module on Topic of Reaction Rate for Senior High School Level Grade XI Chemistry Learning.

Science.gov (United States)

Sari, D. R.; Hardeli; Bayharti

2018-04-01

This study aims to produce chemistry triangle oriented module on topic of reaction rate, and to reveal the validity and practicality level of the generated module. The type of research used is EducationalDesign Research (EDR) with development model is Plompmodel. This model consists of three phases, which are preliminary research, prototyping phase, and assessment phase. The instrument used in this research is questionnaire validity and practicality. The data of the research were analyzed by using Kappa Cohen formula. The chemistry triangle oriented module validation sheet was given to 5 validators consisting of 3 chemistry lecturers and 2 high school chemistry teachers, while the practicality sheet was given to 2 chemistry teachers, 6 students of SMAN 10 Padang grade XII MIA 5 on the small groupevaluation and 25 students of SMAN 10 Padang grade XII MIA 6 on the field test. Based on the questionnaire validity analysis, the validity level of the module is very high with the value of kappa moment 0.87. The level of practicality based on teacher questionnaire response is very high category with a kappa moment value 0.96. Based on the questionnaire of student responses on small group evaluation, the level of practicality is very high category with a kappa moment 0.81, and the practicality is very high category with kappa moment value 0.83 based on questionnaire of student response on field test.

Development of High Temperature Chemistry Measurement System for Establishment of On-Line Water Chemistry Surveillance Network in Nuclear Power Plant

International Nuclear Information System (INIS)

Yeon, Jei Won; Kim, Won Ho; Song, Kyu Seok; Joo, Ki Soo; Choi, Ke Chon; Ha, Yeong Keong; Ahn, Hong Joo; Im, Hee Jung; Maeng, Wan Young

2010-07-01

An integrated high-temperature water chemistry sensor (pH, E redox ) was developed for the establishment of the on-line water chemistry surveillance system in nuclear power plants. The basic performance of the integrated sensor was confirmed in high-temperature (280 .deg. C, 150kg/m 2 ) lithium borate solutions by using the relationship between the concentration of lithium ion and pH-E redox values. Especially, the effects of various environmental factors such as temperature, pressure, and flow rate on YSZ-based pH electrode were evaluated for ensuring the accuracy of high-temperature pH measurement. And the relationships between each water chemistry factor (pH, redox potential, electrical conductivity) were induced for enhancing the credibility of water chemistry measurement. In addition, on the basis of the evaluation of a nuclear plant design company, we suggested potential installation positions of the measurement system in a nuclear power plant

High-temperature chemistry of HCl and Cl2

DEFF Research Database (Denmark)

Pelucchi, Matteo; Frassoldati, Alessio; Faravelli, Tiziano

2015-01-01

The high temperature chlorine chemistry was updated and the inhibition mechanisms involving HCl and Cl2 were re-examined. The thermochemistry was obtained using the Active Thermochemical Tables (ATcT) approach, resulting in improved data for chlorine-containing species of interest. The HCl/Cl2....... The validation was carried out on selected experimental data from laminar flames, shock tubes and plug flow reactors. Systems containing Cl2 showed high sensitivity to Cl2 +M⇌Cl+Cl+M; the rate constant for this reaction has a significant uncertainty and there is a need for an accurate high...... chemistry discussed in the paper was based on reference and experimental measurements of rate constants available in the literature. By coupling the new HCl/Cl2 subset with the Politecnico di Milano (POLIMI) syngas mechanism a kinetic mechanism consisting of 25 species and 102 reactions was obtained...

Experimental Investigation of Turbulence-Chemistry Interaction in High-Reynolds-Number Turbulent Partially Premixed Flames

Science.gov (United States)

2016-06-23

AFRL-AFOSR-VA-TR-2016-0277 Experimental Investigation of Turbulence-Chemistry Interaction in High- Reynolds -Number Turbulent Partially Premixed...4. TITLE AND SUBTITLE [U] Experimental investigation of turbulence-chemistry interaction in high- Reynolds -number 5a. CONTRACT NUMBER turbulent...for public release Final Report: Experimental investigation of turbulence-chemistry interaction in high- Reynolds -number turbulent partially premixed

77 FR 46089 - Agency Information Collection Activities; Proposed Collection; Comment Request; EPA's ENERGY STAR...

Science.gov (United States)

2012-08-02

... Activities; Proposed Collection; Comment Request; EPA's ENERGY STAR Program in the Commercial and Industrial... this action are participants in EPA's ENERGY STAR Program in the Commercial and Industrial Sectors. Title: Information Collection Activities Associated with EPA's ENERGY STAR Program in the Commercial and...

Quadrupole collective dynamics from energy density functionals: Collective Hamiltonian and the interacting boson model

International Nuclear Information System (INIS)

Nomura, K.; Vretenar, D.; Niksic, T.; Otsuka, T.; Shimizu, N.

2011-01-01

Microscopic energy density functionals have become a standard tool for nuclear structure calculations, providing an accurate global description of nuclear ground states and collective excitations. For spectroscopic applications, this framework has to be extended to account for collective correlations related to restoration of symmetries broken by the static mean field, and for fluctuations of collective variables. In this paper, we compare two approaches to five-dimensional quadrupole dynamics: the collective Hamiltonian for quadrupole vibrations and rotations and the interacting boson model (IBM). The two models are compared in a study of the evolution of nonaxial shapes in Pt isotopes. Starting from the binding energy surfaces of 192,194,196 Pt, calculated with a microscopic energy density functional, we analyze the resulting low-energy collective spectra obtained from the collective Hamiltonian, and the corresponding IBM Hamiltonian. The calculated excitation spectra and transition probabilities for the ground-state bands and the γ-vibration bands are compared to the corresponding sequences of experimental states.

DOUBLE SHELL TANK INTEGRITY PROJECT HIGH LEVEL WASTE CHEMISTRY OPTIMIZATION

International Nuclear Information System (INIS)

WASHENFELDER DJ

2008-01-01

The U.S. Department of Energy's Office (DOE) of River Protection (ORP) has a continuing program for chemical optimization to better characterize corrosion behavior of High-Level Waste (HLW). The DOE controls the chemistry in its HLW to minimize the propensity of localized corrosion, such as pitting, and stress corrosion cracking (SCC) in nitrate-containing solutions. By improving the control of localized corrosion and SCC, the ORP can increase the life of the Double-Shell Tank (DST) carbon steel structural components and reduce overall mission costs. The carbon steel tanks at the Hanford Site are critical to the mission of safely managing stored HLW until it can be treated for disposal. The DOE has historically used additions of sodium hydroxide to retard corrosion processes in HLW tanks. This also increases the amount of waste to be treated. The reactions with carbon dioxide from the air and solid chemical species in the tank continually deplete the hydroxide ion concentration, which then requires continued additions. The DOE can reduce overall costs for caustic addition and treatment of waste, and more effectively utilize waste storage capacity by minimizing these chemical additions. Hydroxide addition is a means to control localized and stress corrosion cracking in carbon steel by providing a passive environment. The exact mechanism that causes nitrate to drive the corrosion process is not yet clear. The SCC is less of a concern in the newer stress relieved double shell tanks due to reduced residual stress. The optimization of waste chemistry will further reduce the propensity for SCC. The corrosion testing performed to optimize waste chemistry included cyclic potentiodynamic volarization studies. slow strain rate tests. and stress intensity factor/crack growth rate determinations. Laboratory experimental evidence suggests that nitrite is a highly effective:inhibitor for pitting and SCC in alkaline nitrate environments. Revision of the corrosion control

VII Russian annual conference of young scientists and postgraduate students Physical chemistry and technology of inorganic materials. Collection of materials

International Nuclear Information System (INIS)

Tsvetkov, Yu.V.

2010-01-01

The materials of the VII Russian annual conference of young scientists and postgraduate students Physical chemistry and technology of inorganic materials, held 8-11 November 2010 in Moscow, are presented. Structure and properties of high-strength nanostructured metal and composite materials, development of research methods and simulation of the structure and properties of materials and nanomaterials, functional ceramic and composite nanomaterials - in sight of the participants. The problems of physicochemical principles and processes for new technologies and forming powder materials and nanomaterials, physicochemical bases of production and processing of advanced inorganic materials, physical chemistry and technology of energy-, resource-saving and environmentally friendly processes for ferrous, non-ferrous and rare metals are under consideration. Promising composite coatings and nanostructured films of functional purposes, physicochemical bases of new processes of shaping and forming of materials and nanomaterials are discussed [ru

ACER Chemistry Test Item Collection. ACER Chemtic Year 12.

Science.gov (United States)

Australian Council for Educational Research, Hawthorn.

The chemistry test item banks contains 225 multiple-choice questions suitable for diagnostic and achievement testing; a three-page teacher's guide; answer key with item facilities; an answer sheet; and a 45-item sample achievement test. Although written for the new grade 12 chemistry course in Victoria, Australia, the items are widely applicable.…

Proceedings of the DAE-BRNS fifth interdisciplinary symposium on materials chemistry

International Nuclear Information System (INIS)

Jafar, Mohsin; Tyagi, Adish; Tyagi, Deepak

2014-12-01

The focus of the present symposium on materials chemistry was on research areas in materials chemistry like: nuclear materials; high purity materials; nanomaterials and clusters; carbon based materials; fuel cell materials and other electro-ceramics; biomaterials; polymers and soft condensed matter; materials for energy conversion; thin films and surface chemistry; magnetic materials; catalysis; chemical sensors; organic and organometallic compounds; computational material chemistry etc. Papers relevant to INIS are indexed separately

The use of high impact practices (HIPs) on chemistry lesson design and implementation by pre-service teachers

Science.gov (United States)

Chamrat, Suthida; Apichatyotin, Nattaya; Puakanokhirun, Kittaporn

2018-01-01

The quality of lesson design is essential to learning effectiveness. Research shows some characteristics of lessons have strong effect on learning which were grouped into "High Impact Practices or HIPs. This research aims to examine the use of HIPs on chemistry lesson design as a part of Teaching Science Strand in Chemistry Concepts course. At the first round of lesson design and implementing in classroom, 14 chemistry pre-services teachers freely selected topics, designed and implemented on their own ideas. The lessons have been reflected by instructors and their peers. High Impact Practices were overtly used as the conceptual framework along with the After-Action Review and Reflection (AARR). The selected High Impact practice in this study consisted of 6 elements: well-designed lesson, vary cognitive demand/academic challenge, students center approach, opportunity of students to reflect by discussion or writing, the assignment of project based learning or task, and the lesson reflects pre-service teachers' Technological Pedagogical Content Knowledge (TPACK). The second round, pre-service teachers were encouraged to explicitly used 6 High Impact Practices in cooperated with literature review specified on focused concepts for bettering designed and implemented lessons. The data were collected from 28 lesson plans and 28 classroom observations to compare and discuss between the first and second lesson and implementation. The results indicated that High Impact Practices effect on the quality of delivered lesson. However, there are some elements that vary on changes which were detailed and discussed in this research article.

Non-equilibrium Microwave Plasma for Efficient High Temperature Chemistry.

Science.gov (United States)

van den Bekerom, Dirk; den Harder, Niek; Minea, Teofil; Gatti, Nicola; Linares, Jose Palomares; Bongers, Waldo; van de Sanden, Richard; van Rooij, Gerard

2017-08-01

A flowing microwave plasma based methodology for converting electric energy into internal and/or translational modes of stable molecules with the purpose of efficiently driving non-equilibrium chemistry is discussed. The advantage of a flowing plasma reactor is that continuous chemical processes can be driven with the flexibility of startup times in the seconds timescale. The plasma approach is generically suitable for conversion/activation of stable molecules such as CO2, N2 and CH4. Here the reduction of CO2 to CO is used as a model system: the complementary diagnostics illustrate how a baseline thermodynamic equilibrium conversion can be exceeded by the intrinsic non-equilibrium from high vibrational excitation. Laser (Rayleigh) scattering is used to measure the reactor temperature and Fourier Transform Infrared Spectroscopy (FTIR) to characterize in situ internal (vibrational) excitation as well as the effluent composition to monitor conversion and selectivity.

Recycled Thermal Energy from High Power Light Emitting Diode Light Source.

Science.gov (United States)

Ji, Jae-Hoon; Jo, GaeHun; Ha, Jae-Geun; Koo, Sang-Mo; Kamiko, Masao; Hong, JunHee; Koh, Jung-Hyuk

2018-09-01

In this research, the recycled electrical energy from wasted thermal energy in high power Light Emitting Diode (LED) system will be investigated. The luminous efficiency of lights has been improved in recent years by employing the high power LED system, therefore energy efficiency was improved compared with that of typical lighting sources. To increase energy efficiency of high power LED system further, wasted thermal energy should be re-considered. Therefore, wasted thermal energy was collected and re-used them as electrical energy. The increased electrical efficiency of high power LED devices was accomplished by considering the recycled heat energy, which is wasted thermal energy from the LED. In this work, increased electrical efficiency will be considered and investigated by employing the high power LED system, which has high thermal loss during the operating time. For this research, well designed thermoelement with heat radiation system was employed to enhance the collecting thermal energy from the LED system, and then convert it as recycled electrical energy.

New aspects of high energy density plasma

International Nuclear Information System (INIS)

Hotta, Eiki

2005-10-01

The papers presented at the symposium on 'New aspects of high energy density plasma' held at National Institute for Fusion Science are collected in this proceedings. The papers reflect the present status and recent progress in the experiments and theoretical works on high energy density plasma produced by pulsed power technology. The 13 of the presented papers are indexed individually. (J.P.N.)

Spatiotemporal dynamics of spring and stream water chemistry in a high-mountain area

International Nuclear Information System (INIS)

Zelazny, Miroslaw; Astel, Aleksander; Wolanin, Anna; Malek, Stanislaw

2011-01-01

The present study deals with the application of the self-organizing map (SOM) technique in the exploration of spatiotemporal dynamics of spring and stream water samples collected in the Chocholowski Stream Basin located in the Tatra Mountains (Poland). The SOM-based classification helped to uncover relationships between physical and chemical parameters of water samples and factors determining the quality of water in the studied high-mountain area. In the upper part of the Chocholowski Stream Basin, located on the top of the crystalline core of the Tatras, concentrations of the majority of ionic substances were the lowest due to limited leaching. Significantly higher concentration of ionic substances was detected in spring and stream samples draining sedimentary rocks. The influence of karst-type springs on the quality of stream water was also demonstrated. - Highlights: → We use SOM approach to explore physiochemical data for mountain waters. → Geologic structure and hydrological events impact water chemistry. → Limited leaching, typical of crystalline core, reflects in low water mineralization. → Sedimentary rocks are susceptible for leaching. → Eutrophication has not been shown to be a threat in the Chocholowska Valley. - Spatiotemporal dynamics of spring and stream water chemistry in unique high-mountain area was evaluated by the self-organizing map technique.

3D Printed Potential and Free Energy Surfaces for Teaching Fundamental Concepts in Physical Chemistry

Science.gov (United States)

Kaliakin, Danil S.; Zaari, Ryan R.; Varganov, Sergey A.

2015-01-01

Teaching fundamental physical chemistry concepts such as the potential energy surface, transition state, and reaction path is a challenging task. The traditionally used oversimplified 2D representation of potential and free energy surfaces makes this task even more difficult and often confuses students. We show how this 2D representation can be…

Synthesis and Characterization of Metal-Organic Frameworks (MOFs) for Photon Collection and Energy Transfer

Science.gov (United States)

So, Monica C.

. To address problem (a), we incorporated antenna molecules (i.e. perylene diimides) to expand light collection and then transfer energy to the primary chromophores. To address problem (b), we observed that excitons can achieve up to 2,025 hops in a porphyrin-based metal-organic framework (MOF) single crystal within its 3 ns lifetime. By precisely aligning the chromophores in the MOF, we showed that long-distance exciton transport (i.e. ultra-fast, sequential hopping) was consistent with the well-established Forster theory. To address problems (c) and (d), we introduced MOF components one step at a time to optimize optical path length and crystal-thickness. This allowed us to incorporate MOFs (normally bulk crystals) into a MOF film. The approach exploited both MOF chemistry and layer-by-layer (LbL) assembly of crystalline MOFs in a highly controlled fashion on functional surfaces. We also incorporated good light-harvesting molecules as struts in MOFs to increase the visible absorption. Designing MOF-based OPVs can provide insight into solar energy conversion. This can potentially lead to much higher efficiencies, based on the simultaneous resolution of the four challenges hindering OPV performance.

Non-collective oblate states in iodine isotopes at high spin

Energy Technology Data Exchange (ETDEWEB)

Paul, E S; Ali, I; Cullen, D M; Fallon, P; Forbes, S A; Hanna, F; Nolan, P J [Liverpool Univ. (United Kingdom). Oliver Lodge Lab.; Bentley, M A; Bruce, A M; Simpson, J [Daresbury Lab. (United Kingdom); Clark, R M; Regan, P H; Wadsworth, R [York Univ. (United Kingdom). Dept. of Physics; Fossan, D B; Hughes, J R; Lafosse, D R; Vaska, P; Waring, M P [Department of Physics, SUNY at Stony Brook, NY (United States); Liang, Y [Argonne National Lab., IL (United States); Ma, R [Brookhaven National Lab., Upton, NY (United States)

1992-08-01

Competition between single-particle and collective modes of excitation has been observed in the odd-A {sup 113-119}I isotopes at high spin. A maximally-aligned non-collective 43/2{sup -} configuration at {gamma}=+ 60 degrees is seen at similar excitation energies in these nuclei. 7 refs., 4 figs.

Transverse energy per charged particle in heavy-ion collisions: Role of collective flow

Science.gov (United States)

Kumar Tiwari, Swatantra; Sahoo, Raghunath

2018-03-01

The ratio of (pseudo)rapidity density of transverse energy and the (pseudo)rapidity density of charged particles, which is a measure of the mean transverse energy per particle, is an important observable in high energy heavy-ion collisions. This ratio reveals information about the mechanism of particle production and the freeze-out criteria. Its collision energy and centrality dependence is almost similar to the chemical freeze-out temperature until top Relativistic Heavy-Ion Collider (RHIC) energy. The Large Hadron Collider (LHC) measurement at √{s_{NN}} = 2.76 TeV brings up new challenges towards understanding the phenomena like gluon saturation and role of collective flow, etc. being prevalent at high energies, which could contribute to the above observable. Statistical Hadron Gas Model (SHGM) with a static fireball approximation has been successful in describing both the centrality and energy dependence until top RHIC energies. However, the SHGM predictions for higher energies lie well below the LHC data. In order to understand this, we have incorporated collective flow in an excluded-volume SHGM (EV-SHGM). Our studies suggest that the collective flow plays an important role in describing E T/ N ch and it could be one of the possible parameters to explain the rise observed in E T/ N ch from RHIC to LHC energies. Predictions are made for E T/ N ch , participant pair normalized-transverse energy per unit rapidity and the Bjorken energy density for Pb+Pb collisions at √{s_{NN}} = 5.02 TeV at the Large Hadron Collider.

New trends and developments in radiation chemistry

International Nuclear Information System (INIS)

1989-10-01

Radiation chemistry is a branch of chemistry that studies chemical transformations in materials exposed to high-energy radiations. It uses radiation as the initiator of chemical reactions. Practical applications of radiation chemistry today extend to many fields, including health care, food and agriculture, manufacturing, industrial pollution abatement, biotechnology and telecommunications. The important advantage of radiation chemistry lies in its ability to be used to produce, and study, almost any reactive atomic and molecular species playing a part in chemical reactions, synthesis, industrial processes, or in biological systems. The techniques are applicable to gaseous, liquid, solid, and heterogeneous systems. By combining different techniques of radiation chemistry with analytical chemistry, the reaction mechanism and kinetics of chemical reactions are studied. In November 1988 in Bologna, Italy, the IAEA convened an advisory group meeting to assess new trends and developments in radiation chemistry. The present publication includes most of the contributions presented at the meeting. Refs, figs and tabs

Balance Function in High-Energy Collisions

International Nuclear Information System (INIS)

Tawfik, A.; Shalaby, Asmaa G.

2015-01-01

Aspects and implications of the balance functions (BF) in high-energy physics are reviewed. The various calculations and measurements depending on different quantities, for example, system size, collisions centrality, and beam energy, are discussed. First, the different definitions including advantages and even short-comings are highlighted. It is found that BF, which are mainly presented in terms of relative rapidity, and relative azimuthal and invariant relative momentum, are sensitive to the interaction centrality but not to the beam energy and can be used in estimating the hadronization time and the hadron-quark phase transition. Furthermore, the quark chemistry can be determined. The chemical evolution of the new-state-of-matter, the quark-gluon plasma, and its temporal-spatial evolution, femtoscopy of two-particle correlations, are accessible. The production time of positive-negative pair of charges can be determined from the widths of BF. Due to the reduction in the diffusion time, narrowed widths refer to delayed hadronization. It is concluded that BF are powerful tools characterizing hadron-quark phase transition and estimating some essential properties

The New Color of Chemistry: Green Chemistry

Directory of Open Access Journals (Sweden)

Zuhal GERÇEK

2012-01-01

Full Text Available Green chemistry which is the new application of chemistry rules provides solutions to problems that mankind is faced with climate changes, sustainable agriculture, energy, toxics, depletion of natural sources e.g. designing new chemicals and processes that production and utilization of hazardous matters. So, it is the indispensible tool for sustainable development. Current and future chemists should consider the human health and ecological issues in their professional life. In order to provide a solution for this requirement, green chemistry rules and under standings should be primarily taken in the university curriculum and at all educational levels.

Interactions of Chemistry Teachers with Gifted Students in a Regular High-School Chemistry Classroom

Science.gov (United States)

Benny, Naama; Blonder, Ron

2018-01-01

Regular high-school chemistry teachers view gifted students as one of several types of students in a regular (mixed-ability) classroom. Gifted students have a range of unique abilities that characterize their learning process: mostly they differ in three key learning aspects: their faster learning pace, increased depth of understanding, and…

Higher-capacity lithium ion battery chemistries for improved residential energy storage with micro-cogeneration

International Nuclear Information System (INIS)

Darcovich, K.; Henquin, E.R.; Kenney, B.; Davidson, I.J.; Saldanha, N.; Beausoleil-Morrison, I.

2013-01-01

Highlights: • Characterized two novel high capacity electrode materials for Li-ion batteries. • A numerical discharge model was run to characterize Li-ion cell behavior. • Engineering model of Li-ion battery pack developed from cell fundamentals. • ESP-r model integrated micro-cogeneration and high capacity Li-ion storage. • Higher capacity batteries shown to improve micro-cogeneration systems. - Abstract: Combined heat and power on a residential scale, also known as micro-cogeneration, is currently gaining traction as an energy savings practice. The configuration of micro-cogeneration systems is highly variable, as local climate, energy supply, energy market and the feasibility of including renewable type components such as wind turbines or photovoltaic panels are all factors. Large-scale lithium ion batteries for electrical storage in this context can provide cost savings, operational flexibility, and reduced stress on the distribution grid as well as a degree of contingency for installations relying upon unsteady renewables. Concurrently, significant advances in component materials used to make lithium ion cells offer performance improvements in terms of power output, energy capacity, robustness and longevity, thereby enhancing their prospective utility in residential micro-cogeneration installations. The present study evaluates annual residential energy use for a typical Canadian home connected to the electrical grid, equipped with a micro-cogeneration system consisting of a Stirling engine for supplying heat and power, coupled with a nominal 2 kW/6 kW h lithium ion battery. Two novel battery cathode chemistries, one a new Li–NCA material, the other a high voltage Ni-doped lithium manganate, are compared in the residential micro-cogeneration context with a system equipped with the presently conventional LiMn 2 O 4 spinel-type battery

Analysis of the effect of specific vocabulary instruction on high school chemistry students' knowledge and understanding

Science.gov (United States)

Labrosse, Peggy

The purpose of this study was to analyze the effects of specific vocabulary instruction on high school chemistry students' knowledge and understanding. Students might be able to formally recite a definition for a term without actually having understood the meaning of the term and its connection to other terms or to related concepts. Researchers (Cassels & Johnstone, 1983; Gabel, 1999; Johnstone, 1991) have been studying the difficulty students have in learning science, particularly chemistry. Gabel (1999) suggests that, "while research into misconceptions (also known as alternative conceptions) and problem-solving has dominated the field for the past 25 years, we are no closer to a solution that would improve the teaching and learning of chemistry" (P. 549). Gabel (1999) relates the difficulty in learning chemistry to use of language. She refers to student difficulty both with words that have more than one meaning in English and with words that are used to mean one idea in chemistry and another idea in every day language. The Frayer Model, a research-based teaching strategy, is a graphic organizer which students use to create meaningful definitions for terms in context (Frayer, Frederick, & Klausmeier, 1969). It was used as the treatment---the specific vocabulary instruction---in this research study. The researcher collected and analyzed data to answer three research questions that focused on the effect of using the Frayer model (a graphic organizer) on high school students' knowledge and understanding of academic language used in chemistry. The research took place in a New England high school. Four intact chemistry classes provided the student participants; two classes were assigned to the treatment group (TG) and two classes were assigned to the control group (CG). The TG received vocabulary instruction on 14 chosen terms using the Frayer Model. The CG received traditional vocabulary instruction with no special attention to the 14 terms selected for this study

Sustainable technological development in chemistry. Improving the quality of life through chemistry and agriculture

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-08-01

The importance of agricultural products, their potential conversion to energy sources and their applications for fibre-reinforced construction materials is emphasized. Another potentially important technology is the conversion of sunlight into electricity such as occurs in the leaves of plants. Parallels with nature exist, even though conversions with inorganic materials have, until now, been promising. The ability to control chemical reactions is the subject throughout all the following chapters. The goal is to achieve high reaction efficiencies and to use fewer basic materials, both of which will lead to a reduction in environmental stress. Sustainable developments in chemistry can be described by two approaches: (1) Improvements in society, with challenges for chemistry; and (2) Improvement in the chemical sector itself. Both approaches are dealt with in this report. Five areas for development have been chosen in the discussions for `DTO-Chemie`: Integrated plant conversion (IPC), in particular Valorisation of plant parts for raw materials and energy; Biomass conversion (C1 Chemistry), in particular Technologies for (among others) C1-based chemicals and energy carriers; Photovoltaic cells (PSC), in particular Technologies for the conversion of solar light into electricity; Process Technology in Fine chemistry (PFC), in particular Methodology of manufacturing processes for Fine chemicals; and Sustainable Construction Materials (FRC); in particular Techniques for using fibre-reinforced composites in construction applications. These areas can be viewed as clusters of technologies, with a strong chemistry and agricultural component, which are necessary for achieving a sustainable future. Furthermore, it is important to recognise that technology requires a progressive development (technology lifecycle). The five areas of technology development are tested against a number of criteria: (1) Sustainability / leap / volume; (2) Horizon 2050; (3) Commitment from industry

CPAC: Energy-Efficient Data Collection through Adaptive Selection of Compression Algorithms for Sensor Networks

Science.gov (United States)

Lee, HyungJune; Kim, HyunSeok; Chang, Ik Joon

2014-01-01

We propose a technique to optimize the energy efficiency of data collection in sensor networks by exploiting a selective data compression. To achieve such an aim, we need to make optimal decisions regarding two aspects: (1) which sensor nodes should execute compression; and (2) which compression algorithm should be used by the selected sensor nodes. We formulate this problem into binary integer programs, which provide an energy-optimal solution under the given latency constraint. Our simulation results show that the optimization algorithm significantly reduces the overall network-wide energy consumption for data collection. In the environment having a stationary sink from stationary sensor nodes, the optimized data collection shows 47% energy savings compared to the state-of-the-art collection protocol (CTP). More importantly, we demonstrate that our optimized data collection provides the best performance in an intermittent network under high interference. In such networks, we found that the selective compression for frequent packet retransmissions saves up to 55% energy compared to the best known protocol. PMID:24721763

Chemistry Division annual progress report for period ending April 30, 1993

Energy Technology Data Exchange (ETDEWEB)

Poutsma, M.L.; Ferris, L.M.; Mesmer, R.E.

1993-08-01

The Chemistry Division conducts basic and applied chemical research on projects important to DOE`s missions in sciences, energy technologies, advanced materials, and waste management/environmental restoration; it also conducts complementary research for other sponsors. The research are arranged according to: coal chemistry, aqueous chemistry at high temperatures and pressures, geochemistry, chemistry of advanced inorganic materials, structure and dynamics of advanced polymeric materials, chemistry of transuranium elements and compounds, chemical and structural principles in solvent extraction, surface science related to heterogeneous catalysis, photolytic transformations of hazardous organics, DNA sequencing and mapping, and special topics.

Chemistry for the nuclear energy of the future

International Nuclear Information System (INIS)

Chmielewski, A.G.

2011-01-01

Chemistry - radiochemistry, radiation chemistry and nuclear chemical engineering play a very important role in the nuclear power development. Even at present, the offered technology is well developed, but still several improvements are needed and proposed. These developments concern all stages of the technology; front end, reactor operation (coolant chemistry and installation components decontamination, noble gas release control), back end of fuel cycle, etc. Chemistry for a partitioning and a transmutation is a new challenge for the chemists and chemical engineers. The IV th generation of nuclear reactors cannot be developed without chemical solutions for fuel fabrication, radiation-coolants interaction phenomena understanding and spent fuel/waste treatment technologies elaboration. Radiochemical analytical methods are fundamental for radioecological monitoring of radioisotopes of natural and anthropological origin. This paper addresses just a few subjects and is not a detailed overview of the field, however it illustrates a role of chemistry for a safe and economical nuclear power development. (author)

High fidelity chemistry and radiation modeling for oxy -- combustion scenarios

Science.gov (United States)

Abdul Sater, Hassan A.

To account for the thermal and chemical effects associated with the high CO2 concentrations in an oxy-combustion atmosphere, several refined gas-phase chemistry and radiative property models have been formulated for laminar to highly turbulent systems. This thesis examines the accuracies of several chemistry and radiative property models employed in computational fluid dynamic (CFD) simulations of laminar to transitional oxy-methane diffusion flames by comparing their predictions against experimental data. Literature review about chemistry and radiation modeling in oxy-combustion atmospheres considered turbulent systems where the predictions are impacted by the interplay and accuracies of the turbulence, radiation and chemistry models. Thus, by considering a laminar system we minimize the impact of turbulence and the uncertainties associated with turbulence models. In the first section of this thesis, an assessment and validation of gray and non-gray formulations of a recently proposed weighted-sum-of-gray gas model in oxy-combustion scenarios was undertaken. Predictions of gas, wall temperatures and flame lengths were in good agreement with experimental measurements. The temperature and flame length predictions were not sensitive to the radiative property model employed. However, there were significant variations between the gray and non-gray model radiant fraction predictions with the variations in general increasing with decrease in Reynolds numbers possibly attributed to shorter flames and steeper temperature gradients. The results of this section confirm that non-gray model predictions of radiative heat fluxes are more accurate than gray model predictions especially at steeper temperature gradients. In the second section, the accuracies of three gas-phase chemistry models were assessed by comparing their predictions against experimental measurements of temperature, species concentrations and flame lengths. The chemistry was modeled employing the Eddy

Life in the fast lane: high-throughput chemistry for lead generation and optimisation.

Science.gov (United States)

Hunter, D

2001-01-01

The pharmaceutical industry has come under increasing pressure due to regulatory restrictions on the marketing and pricing of drugs, competition, and the escalating costs of developing new drugs. These forces can be addressed by the identification of novel targets, reductions in the development time of new drugs, and increased productivity. Emphasis has been placed on identifying and validating new targets and on lead generation: the response from industry has been very evident in genomics and high throughput screening, where new technologies have been applied, usually coupled with a high degree of automation. The combination of numerous new potential biological targets and the ability to screen large numbers of compounds against many of these targets has generated the need for large diverse compound collections. To address this requirement, high-throughput chemistry has become an integral part of the drug discovery process. Copyright 2002 Wiley-Liss, Inc.

Progress in organic and physical chemistry structures and mechanisms

CERN Document Server

Zaikov, Gennady E; Lobanov, Anton V

2013-01-01

Progress in Organic and Physical Chemistry: Structures and Mechanisms provides a collection of new research in the field of organic and physical properties, including new research on: The physical principles of the conductivity of electrical conducting polymer compounds The dependence on constants of electromagnetic interactions upon electron spacial-energy characteristics Effects of chitosan molecultural weight on rehological behavior of chitosan modified nanoclay at hight hydrated state Bio-structural energy criteria of functional states in normal and pathological conditions Potentiometric study on the international between devalent cations and sodium carboxylates in aqueous solutions Structural characteristic changes in erythrocyte membranes of mice bearing Alzheimer's-like disease caused by the olfactory bulbetomy This volume is intended to provide an overview of new studies and research for engineers, faculty, researchers, and upper-level students in the field of organic and physical chemistry.

Scientific Information Analysis of Chemistry Dissertations Using Thesaurus of Chemistry

Directory of Open Access Journals (Sweden)

Taghi Rajabi

2017-09-01

Full Text Available : Concept maps of chemistry can be obtained from thesaurus of chemistry. Analysis of information in the field of chemistry is done at graduate level, based on comparing and analyzing chemistry dissertations by using these maps. Therefore, the use of thesaurus for analyzing scientific information is recommended. Major advantage of using this method, is that it is possible to obtain a detailed map of all academic researches across all branches of science. The researches analysis results in chemical science can play a key role in developing strategic research policies, educational programming, linking universities to industries and postgraduate educational programming. This paper will first introduce the concept maps of chemistry. Then, emerging patterns from the concept maps of chemistry will be used to analyze the trend in the academic dissertations in chemistry, using the data collected and stored in our database at Iranian Research Institute for Information Science and Technology (IranDoc over the past 10 years (1998-2009.

Toward Low-Cost, High-Energy Density, and High-Power Density Lithium-Ion Batteries

Science.gov (United States)

Li, Jianlin; Du, Zhijia; Ruther, Rose E.; AN, Seong Jin; David, Lamuel Abraham; Hays, Kevin; Wood, Marissa; Phillip, Nathan D.; Sheng, Yangping; Mao, Chengyu; Kalnaus, Sergiy; Daniel, Claus; Wood, David L.

2017-09-01

Reducing cost and increasing energy density are two barriers for widespread application of lithium-ion batteries in electric vehicles. Although the cost of electric vehicle batteries has been reduced by 70% from 2008 to 2015, the current battery pack cost (268/kWh in 2015) is still >2 times what the USABC targets (125/kWh). Even though many advancements in cell chemistry have been realized since the lithium-ion battery was first commercialized in 1991, few major breakthroughs have occurred in the past decade. Therefore, future cost reduction will rely on cell manufacturing and broader market acceptance. This article discusses three major aspects for cost reduction: (1) quality control to minimize scrap rate in cell manufacturing; (2) novel electrode processing and engineering to reduce processing cost and increase energy density and throughputs; and (3) material development and optimization for lithium-ion batteries with high-energy density. Insights on increasing energy and power densities of lithium-ion batteries are also addressed.

Pretreatment data is highly predictive of liver chemistry signals in clinical trials.

Science.gov (United States)

Cai, Zhaohui; Bresell, Anders; Steinberg, Mark H; Silberg, Debra G; Furlong, Stephen T

2012-01-01

The goal of this retrospective analysis was to assess how well predictive models could determine which patients would develop liver chemistry signals during clinical trials based on their pretreatment (baseline) information. Based on data from 24 late-stage clinical trials, classification models were developed to predict liver chemistry outcomes using baseline information, which included demographics, medical history, concomitant medications, and baseline laboratory results. Predictive models using baseline data predicted which patients would develop liver signals during the trials with average validation accuracy around 80%. Baseline levels of individual liver chemistry tests were most important for predicting their own elevations during the trials. High bilirubin levels at baseline were not uncommon and were associated with a high risk of developing biochemical Hy's law cases. Baseline γ-glutamyltransferase (GGT) level appeared to have some predictive value, but did not increase predictability beyond using established liver chemistry tests. It is possible to predict which patients are at a higher risk of developing liver chemistry signals using pretreatment (baseline) data. Derived knowledge from such predictions may allow proactive and targeted risk management, and the type of analysis described here could help determine whether new biomarkers offer improved performance over established ones.

A Case Study of the Common Difficulties Experienced by High School Students in Chemistry Classroom in Gilgit-Baltistan (Pakistan

Directory of Open Access Journals (Sweden)

Takbir Ali

2012-05-01

Full Text Available This article reports a research study conducted with four chemistry teachers in three high schools (two government schools and one private school in Gilgit-Baltistan region of Pakistan. The study investigated questions concerning common difficulties high school (Grades 9 and 10 students experience in chemistry classroom, the possible reasons for these difficulties, and the ways in which teachers help students overcome these difficulties. A qualitative case study method was used to investigate the questions, which used in-depth interviews with teachers, classroom observation, and postobservation discussion with the teachers, as main data collection tools. The key findings of the study allude to a huge gap between what is intended in the National Curriculum in terms of students’ learning in chemistry and what actually happens in the classroom where students learn chemistry. Promoting in-depth learning appeared to be an uphill task for the teachers. The main hurdle lies in students’ inability to demonstrate a good understanding of very basic concepts of the subject. Despite faced with such a challenge, the teachers appear to be committed to teaching their subject. The implications of the results of the study are explained in the context of schools, teachers, and other educational stakeholders by emphasizing the need for synchronization and integration of efforts on the part of schools.

How wide is the gap between high school and first-year chemistry at ...

African Journals Online (AJOL)

The aim of the study was to identify the nature and extent of the gap between high school and first-year chemistry at the University of the Witwatersrand. The investigation was done at the macro and micro levels. At the macro level high school physical science and first-year chemistry syllabuses were compared. The testing ...

The New Color of Chemistry: Green Chemistry

OpenAIRE

Zuhal GERÇEK

2012-01-01

Green chemistry which is the new application of chemistry rules provides solutions to problems that mankind is faced with climate changes, sustainable agriculture, energy, toxics, depletion of natural sources e.g. designing new chemicals and processes that production and utilization of hazardous matters. So, it is the indispensible tool for sustainable development. Current and future chemists should consider the human health and ecological issues in their professional life. In order to provid...

Conference 'Chemistry of hydrides' Proceedings

International Nuclear Information System (INIS)

1991-07-01

This collection of thesis of conference of Chemistry hydrides presents the results of investigations concerning of base questions of chemistry of nonorganic hydrides, including synthesis questions, studying of physical and chemical properties, thermodynamics, analytical chemistry, investigation of structure, equilibriums in the systems of metal-hydrogen, behaviour of nonorganic hydrides in non-water mediums and applying investigations in the chemistry area and technology of nonorganic hydrides

Multiparticle Collectivity from Initial State Correlations in High Energy Proton-Nucleus Collisions

Science.gov (United States)

Dusling, Kevin; Mace, Mark; Venugopalan, Raju

2018-01-01

Qualitative features of multiparticle correlations in light-heavy ion (p +A ) collisions at RHIC and LHC are reproduced in a simple initial state model of partons in the projectile coherently scattering off localized domains of color charge in the heavy nuclear target. These include (i) the ordering of the magnitudes of the azimuthal angle n th Fourier harmonics of two-particle correlations vn{2 }, (ii) the energy and transverse momentum dependence of the four-particle Fourier harmonic v2{4 }, and (iii) the energy dependence of four-particle symmetric cumulants measuring correlations between different Fourier harmonics. Similar patterns are seen in an Abelian version of the model, where we observe v2{2 }>v2{4 }≈v2{6 }≈v2{8 } of two, four, six, and eight particle correlations. While such patterns are often interpreted as signatures of collectivity arising from hydrodynamic flow, our results provide an alternative description of the multiparticle correlations seen in p +A collisions.

Factors Affecting Energy Barriers for Pyramidal Inversion in Amines and Phosphines: A Computational Chemistry Lab Exercise

Science.gov (United States)

Montgomery, Craig D.

2013-01-01

An undergraduate exercise in computational chemistry that investigates the energy barrier for pyramidal inversion of amines and phosphines is presented. Semiempirical calculations (PM3) of the ground-state and transition-state energies for NR[superscript 1]R[superscript 2]R[superscript 3] and PR[superscript 1]R[superscript 2]R[superscript 3] allow…

Collecting Solar Energy. Solar Energy Education Project.

Science.gov (United States)

O'Brien, Alexander

This solar energy learning module for use with junior high school students offers a list of activities, a pre-post test, job titles, basic solar energy vocabulary, and diagrams of solar energy collectors and installations. The purpose is to familiarize students with applications of solar energy and titles of jobs where this knowledge could be…

Modern trends in contemporary chemistry

International Nuclear Information System (INIS)

Javed, H.; Pervez, H.; Qadeer, R.

1993-01-01

This publication contains a collection of papers presented at symposium on M odern Trends in Contemporary Chemistry , that was held in Islamabad, Pakistan, March 6-8, 1990. The symposium was divided into five sections for presentation of about 55 scientific and technical papers and 6 review papers. The contents of these papers were of good quality in the widespread concern in new trends of chemistry. The six reviews papers covered fields of ortho metallation reactions, evaluation of heterogeneous electron transfer rate contents, macro reticular ion-exchange resins, spectrochemical analytical techniques, liquid crystal-high technology materials for practical applications and trends in advanced ceramics. (A.B.)

Joint Mobile Data Collection and Wireless Energy Transfer in Wireless Rechargeable Sensor Networks.

Science.gov (United States)

Zhong, Ping; Li, Ya-Ting; Liu, Wei-Rong; Duan, Gui-Hua; Chen, Ying-Wen; Xiong, Neal

2017-08-16

In wireless rechargeable sensor networks (WRSNs), there is a way to use mobile vehicles to charge node and collect data. It is a rational pattern to use two types of vehicles, one is for energy charging, and the other is for data collecting. These two types of vehicles, data collection vehicles (DCVs) and wireless charging vehicles (WCVs), are employed to achieve high efficiency in both data gathering and energy consumption. To handle the complex scheduling problem of multiple vehicles in large-scale networks, a twice-partition algorithm based on center points is proposed to divide the network into several parts. In addition, an anchor selection algorithm based on the tradeoff between neighbor amount and residual energy, named AS-NAE, is proposed to collect the zonal data. It can reduce the data transmission delay and the energy consumption for DCVs' movement in the zonal. Besides, we design an optimization function to achieve maximum data throughput by adjusting data rate and link rate of each node. Finally, the effectiveness of proposed algorithm is validated by numerical simulation results in WRSNs.

Development of a microlesson in teaching energy levels of atoms

Science.gov (United States)

Rodriguez, Cherilyn A.; Buan, Amelia T.

2018-01-01

Energy levels of atoms is one of the difficult topics in understanding atomic structure of matter. It appears tobe abstract, theoretical and needs visual representation and images. Hence, in this study a microlesson in teaching the high school chemistry concept on the energy levels of atoms is developed and validated. The researchers utilized backward curriculum design in planning the microlesson to meet the standards of the science K-12 curriculum. The planning process of the microlesson involved a) Identifying the learning competencies in K-12 science curriculum b) write learning objectives c) planning of assessment tools d) making a storyboard e) designing the microlesson and validate and revise the microlesson. The microlesson made use of varied resources in the internet from which the students accessed and collected information about energy levels of atoms. Working in groups, the students synthesized the information on how and why fireworks produce various colors of light through a post card. Findings of the study showed that there was an increase of achievement in learning the content and the students were highly motivated to learn chemistry. Furthermore, the students perceived that the microlesson helped them to understand the chemistry concept through the use of appropriate multimedia activities.

Mean charged hadron multiplicities in high-energy collisions

Energy Technology Data Exchange (ETDEWEB)

Albini, E [Istituto di Matematica dell' Universita Cattolica di Brescia (Italy); Capiluppi, P; Giacomelli, G; Rossi, A M [Bologna Univ. (Italy). Istituto di Fisica

1976-03-01

A collection of mean charged hadron multiplicities per inelastic collision in various high-energy processes is presented. An extensive list of fits of as a function of energy is presented and discussed. As the energy increases the multiplicities for different collisions tend to a unique curve, independent of the type of colliding particles.

Per-Olov Löwdin - father of quantum chemistry

Science.gov (United States)

Brändas, Erkki J.

2017-09-01

During 2016, we celebrate the 100th anniversary of the birth of Per-Olov Löwdin. He was appointed to the first Lehrstuhl in quantum chemistry at Uppsala University in 1960. Löwdin introduced quantum chemistry as a field in its own right by formulating its goals, establishing fundamental concepts, like the correlation energy, the method of configuration interaction, reduced density matrices, natural spin orbitals, charge and bond order matrices, symmetric orthogonalisation, and generalised self-consistent fields. His exposition of partitioning technique and perturbation theory, wave and reaction operators and associated non-linear summation techniques, introduced mathematical rigour and deductive order in the interpretative organisation of the new field. He brought the first computer to Uppsala University and pioneered the initiation of 'electronic brains' and anticipated their significance for quantum chemistry. Perhaps his single most influential contribution to the field was his education of two generations of future faculty in quantum chemistry through Summer Schools in the Scandinavian Mountains, Winter Institutes at Sanibel Island in the Gulf of Mexico. Per-Olov Löwdin founded the book series Advances in Quantum Chemistry and the International Journal of Quantum Chemistry. The evolution of quantum chemistry is appraised, starting from a collection of cross-disciplinary applications of quantum mechanics to the technologically advanced and predominant field of today, virtually used in all branches of chemistry. The scientific work of Per-Olov Löwdin has been crucial for the development of this new important province of science.

Green Chemistry with Microwave Energy

Science.gov (United States)

Green chemistry utilizes a set of 12 principles that reduces or eliminates the use or generation of hazardous substances in the design, manufacture, and applications of chemical products (1). This newer chemical approach protects the environment by inventing safer and eco-friendl...

RADIATION CHEMISTRY 2010 GORDON RESEARCH CONFERENCE JULY 18-23

Energy Technology Data Exchange (ETDEWEB)

Thomas Orlando

2010-07-23

The 2010 Gordon Conference on Radiation Chemistry will present cutting edge research regarding the study of radiation-induced chemical transformations. Radiation Chemistry or 'high energy' chemistry is primarily initiated by ionizing radiation: i.e. photons or particles with energy sufficient to create conduction band electrons and 'holes', excitons, ionic and neutral free radicals, highly excited states, and solvated electrons. These transients often interact or 'react' to form products vastly different than those produced under thermal equilibrium conditions. The non-equilibrium, non-thermal conditions driving radiation chemistry exist in plasmas, star-forming regions, the outer solar system, nuclear reactors, nuclear waste repositories, radiation-based medical/clinical treatment centers and in radiation/materials processing facilities. The 2010 conference has a strong interdisciplinary flavor with focus areas spanning (1) the fundamental physics and chemistry involved in ultrafast (atto/femtosecond) energy deposition events, (2) radiation-induced processes in biology (particularly spatially resolved studies), (3) radiation-induced modification of materials at the nanoscale and cosmic ray/x-ray mediated processes in planetary science/astrochemistry. While the conference concentrates on fundamental science, topical applied areas covered will also include nuclear power, materials/polymer processing, and clinical/radiation treatment in medicine. The Conference will bring together investigators at the forefront of their field, and will provide opportunities for junior scientists and graduate students to present work in poster format or as contributors to the Young Investigator session. The program and format provides excellent avenues to promote cross-disciplinary collaborations.

Research reactor utilization in chemistry programmes

International Nuclear Information System (INIS)

Bautista, E.

1983-01-01

The establishment and roles of the Philippines Atomic Energy Commission in promoting and regulating the use of atomic energy are explained. The research reactor, PRR-1 is being converted to TRIGA to meet the increasing demands of high-flux. The activities of PAEC in chemistry research programs utilizing reactor are discussed in detail. The current and future plans of Research and Development programs are also included. (A.J.)

Report of the joint seminar on heavy-ion nuclear physics and nuclear chemistry in the energy region of tandem accelerators (II)

International Nuclear Information System (INIS)

1986-04-01

A meeting of the second joint seminar on Heavy-Ion Nuclear Physics and Nuclear Chemistry in the Energy Region of Tandem Accelerators was held after an interval of two years at the Tokai Research Establishment of the JAERI, for three days from January 9 to 11, 1986. In the seminar, about 70 nuclear physicists and nuclear chemists of JAERI and other Institutes participated, and 38 papers were presented. These include general reviews and topical subjects which have been developed intensively in recent years, as well as the new results obtained by using the JAERI tandem accelerator. This report is a collection of the papers presented to the seminar. (author)

Symposium on the Physical Chemistry of Solar Energy Conversion, Indianapolis American Chemical Society Meetings, Fall 2013

Energy Technology Data Exchange (ETDEWEB)

Lian, Tianquan [PI, Emory Univ.

2013-09-20

The Symposium on the Physical Chemistry of Solar Energy Conversion at the Fall ACS Meeting in Indianapolis, IN (Sept. 8-12) featured the following sessions (approx. 6 speakers per session): (1) Quantum Dots and Nanorods for Solar Energy Conversion (2 half-day sessions); (2) Artificial Photosynthesis: Water Oxidation; (3) Artificial Photosynthesis: Solar Fuels (2 half-day sessions); (4) Organic Solar Cells; (5) Novel Concepts for Solar Energy Conversion (2 half-day sessions); (6) Emerging Techniques for Solar Energy Conversion; (7) Interfacial Electron Transfer

Handbook on process and chemistry on nuclear fuel reprocessing

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Atsuyuki [Tokyo Univ., Tokyo (Japan); Asakura, Toshihide; Adachi, Takeo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; and others

2001-12-01

'Wet-type' nuclear fuel reprocessing technology, based on PUREX technology, has wide applicability as the principal reprocessing technology of the first generation, and relating technologies, waste management for example, are highly developed, too. It is quite important to establish a database summarizing fundamental information about the process and the chemistry of 'wet-type' reprocessing, because it contributes to establish and develop fuel reprocessing process and nuclear fuel cycle treating high burn-up UO{sub 2} fuel and spent MOX fuel, and to utilize 'wet-type' reprocessing technology much widely. This handbook summarizes the fundamental data on process and chemistry, which was collected and examined by 'Editing Committee of Handbook on Process and Chemistry of Nuclear Fuel Reprocessing', from FY 1993 until FY 2000. (author)

Handbook on process and chemistry on nuclear fuel reprocessing

International Nuclear Information System (INIS)

Suzuki, Atsuyuki; Asakura, Toshihide; Adachi, Takeo

2001-12-01

'Wet-type' nuclear fuel reprocessing technology, based on PUREX technology, has wide applicability as the principal reprocessing technology of the first generation, and relating technologies, waste management for example, are highly developed, too. It is quite important to establish a database summarizing fundamental information about the process and the chemistry of 'wet-type' reprocessing, because it contributes to establish and develop fuel reprocessing process and nuclear fuel cycle treating high burn-up UO 2 fuel and spent MOX fuel, and to utilize 'wet-type' reprocessing technology much widely. This handbook summarizes the fundamental data on process and chemistry, which was collected and examined by 'Editing Committee of Handbook on Process and Chemistry of Nuclear Fuel Reprocessing', from FY 1993 until FY 2000. (author)

Research on data collection key technology of smart electric energy meters

Science.gov (United States)

Chen, Xiangqun; Huang, Rui; Shen, Liman; Chen, Hao; Xiong, Dezhi; Xiao, Xiangqi; Mouhailiu; Renheng, Xu

2018-02-01

In recent years, smart electric energy meters are demand at 70 million to 90 million with the strong smart grid construction every year in China. However, there are some issues in smart electric energy meters data collection such as the interference of environment, low collection efficiency and inability to work when the power is off. In order to solve these issues above, it uses the RFID communication technology to collect the numbers and electric energy information of smart electric energy meters on the basis of the existing smart electric energy meters, and the related data collection communication experiments were made. The experimental result shows that the electric information and other data batch collection of RFID smart electric energy meters are realized in power and power off. It improves the efficiency and the overall success rate is 99.2% within 2 meters. It provides a new method for smart electric energy meters data collection.

The effect of high school chemistry instruction on students' academic self-concept

Science.gov (United States)

Morgan, Peter Wallace

The purpose of this study was to investigate the effect of extended instruction in high school chemistry on the academic self-concept of students and determine what parts of the learning experience need to be addressed to make the interaction a more positive one. Fifty-seven students from three metropolitan public schools, who were enrolled in college preparatory chemistry classes, were asked to complete a written instrument, before and after extended chemistry instruction, that measures academic self-concept. Twenty-one of the students who took part in the written task volunteered to answer some in-depth interview questions concerning their academic self-concept and its relationship to chemistry instruction. Student responses, instrument scores, and student chemistry grades were analyzed for a variety of chemistry learning--academic self-concept connections and interactions. Results showed that there was a positive interaction for less than half of the students involved in the interview sessions. The results from the written instrument showed similar findings. Comparing chemistry grades and academic self-concept revealed an uncertain connection between the two, especially for students with strong academic self-concepts. Students felt that the laboratory experience was often disconnected from the remainder of chemistry instruction and recommended that the laboratory experience be integrated with classroom work. Students also expressed concerns regarding the volume of algorithmic mathematical calculations associated with college preparatory chemistry instruction. Results of this study suggest that secondary chemistry instruction must become more aware of the affective domain of learning and develop a mindful awareness of its connection to the cognitive domain if chemistry teaching and learning is going to better facilitate the intellectual growth of secondary students.

Collective properties and shapes of nuclei at very high spins

International Nuclear Information System (INIS)

Johnson, N.R.

1991-01-01

A topic which has been of major interest to us for some years now involves the evolution of nuclear collectivity at high rotational frequencies and the accompanying changes in the shapes of nuclei in these extreme conditions. We carry out these studies by determining the dynamic electromagnetic multipole moments which are a reflection of the collective aspects of the nuclear wave functions. The most direct way to get these multipole moments is by measurements of excited-state lifetimes which provide the transition matrix elements in a fairly straightforward fashion. Although the primary emphasis of this paper is on the collectivity of the high-spin states in 160 Yb and 164 Yb, it is important to review briefly some work we began about ten years ago lifetime studies of moderately high spins in nuclei near N=90 using the recoil-distance (RD) method. These nuclei are just at the onset of permanent deformation and are known to be very soft with respect to deformation changes. This softness is clearly illustrated in contour diagrams of their potential-energy surfaces. For example, the potential energy surface of 160 Yb reveals that the minimum in the potential occurs around var-epsilon ∼ 0.2 and that it is very shallow in the γ degree of freedom. Because of their γ softness, we have studied several nuclei near N=90 to assess to what extent the polarization effects induced by rotation alignment of high-j quasiparticles affect their collectivity

Canonical Pedagogical Content Knowledge by Cores for Teaching Acid-Base Chemistry at High School

Science.gov (United States)

Alvarado, Clara; Cañada, Florentina; Garritz, Andoni; Mellado, Vicente

2015-01-01

The topic of acid-base chemistry is one of the oldest in general chemistry courses and it has been almost continuously in academic discussion. The central purpose of documenting the knowledge and beliefs of a group of ten Mexican teachers with experience in teaching acid-base chemistry in high school was to know how they design, prepare and…

Presidential Green Chemistry Challenge: 2011 Greener Reaction Conditions Award

Science.gov (United States)

Presidential Green Chemistry Challenge 2011 award winner, Kraton Performance Polymers, developed halogen-free, high-flow NEXAR polymer membranes using less solvent that save energy during reverse osmosis to desalinate water.

Effective Chemistry Communication in Informal Environments

Science.gov (United States)

National Academies Press, 2016

2016-01-01

Chemistry plays a critical role in daily life, impacting areas such as medicine and health, consumer products, energy production, the ecosystem, and many other areas. Communicating about chemistry in informal environments has the potential to raise public interest and understanding of chemistry around the world. However, the chemistry community…

Use of high energy radiation in decomposition and removal of organic water pollutants

International Nuclear Information System (INIS)

Toelgyessy, P.

1990-01-01

The present review deals with the radiation chemistry of dilute aqueous solutions of organic substances emphasizing the possibility of use of high energy radiation in waste water treatment. Effects of radiation on biodegradability, toxicity to water organisms and changes in molecules of solutes showing resistance to biochemical degradation and toxicity to water organisms are discussed. (author) 31 refs

EIA's Role in Energy Data Collection, With Some Notes on Water Data

Science.gov (United States)

Leckey, T. J.

2017-12-01

The U.S. Energy Information Administration (EIA) is the statistical and analytical agency within the U.S. Department of Energy. EIA collects, analyzes, and disseminates independent and impartial energy information to promote sound policymaking, efficient markets, and public understanding of energy and its interaction with the economy and the environment. EIA conducts a comprehensive data collection program that covers the full spectrum of energy sources, end uses, and energy flows. This presentation will describe EIA's authority to collect energy data, report on the range of energy areas currently collected by EIA, discuss some areas where energy information and water issues intersect, and describe the relatively few areas where EIA does collect a small amount of water data. The presentation will conclude with some thoughts about necessary components for effective collection of water data at the federal level.

Radiation Chemistry 2008 Gordon Research Conference - July 6-11, 2008

International Nuclear Information System (INIS)

Bartels, David M.

2009-01-01

Radiation Chemistry is chemistry initiated by ionizing radiation: i.e. photons or particles with energy sufficient to create charge pairs and/or free radicals in a medium. The important transients include conduction band electrons and 'holes', excitons, ionic and neutral free radicals, highly excited states, and solvated electrons. Effects of radiation span timescales from the energy deposition in femtoseconds, through geminate recombination in picoseconds and nanoseconds, to fast radical chemistry in microseconds and milliseconds, and ultimately to processes like cancer occurring decades later. The radiation sources used to study these processes likewise run from femtosecond lasers to nanosecond accelerators to years of gamma irradiation. As a result the conference has a strong interdisciplinary flavor ranging from fundamental physics to clinical biology. While the conference focuses on fundamental science, application areas highlighted in the present conference will include nuclear power, polymer processing, and extraterrestrial chemistry.

Progress report 1981-1982. Reactor Chemistry Department

International Nuclear Information System (INIS)

1983-08-01

Review of the activities performed by the Reactor Chemistry Department of the National Atomic Energy Commission of Argentina during 1981-1982. This Department provides services and assistance in all matters related to water chemistry and nuclear reactors chemistry, in all their phases: design, construction, commissioning and decommissioning. During this period, the following tasks were performed: study of the metallic oxide-water interphases; determination of the goethite and magnetite surficial charges; synthesis of the monodispersed nickel ferrites; study of the iron oxides dissolution mechanism in presence of different complexing agents; chemical decontamination of structural metals; thermodynamics of the water-nitrogen system; physico-chemical studies of aqueous solutions at high temperatures; hydrothermal decomposition of ionic exchange resines and study of the equilibria of the anionic exchange for the chemistry of pressurized reactor's primary loops. The appendix includes information on the Reactor Chemistry Department staff, its publications, services, seminars, courses and conferences performed during 1981-1982. (R.J.S.) [es

Finding the Connections between a High-School Chemistry Curriculum and Nano-Scale Science and Technology

Science.gov (United States)

Blonder, Ron; Sakhnini, Sohair

2017-01-01

The high-school chemistry curriculum is loaded with many important chemical concepts that are taught at the high-school level and it is therefore very difficult to add modern contents to the existing curriculum. However, many studies have underscored the importance of integrating modern chemistry contents such as nanotechnology into a high-school…

Mathematical problems for chemistry students

CERN Document Server

Pota, Gyorgy

2011-01-01

Mathematical Problems for Chemistry Students has been compiled and written (a) to help chemistrystudents in their mathematical studies by providing them with mathematical problems really occurring in chemistry (b) to help practising chemists to activate their applied mathematical skills and (c) to introduce students and specialistsof the chemistry-related fields (physicists, mathematicians, biologists, etc.) intothe world of the chemical applications.Some problems of the collection are mathematical reformulations of those in the standard textbooks of chemistry, others we

78 FR 29749 - Office of Energy Efficiency and Renewable Energy; Agency Information Collection Extension

Science.gov (United States)

2013-05-21

... DEPARTMENT OF ENERGY Office of Energy Efficiency and Renewable Energy; Agency Information Collection Extension AGENCY: Office of Energy Efficiency and Renewable Energy, U.S. Department of Energy (DOE..., DC 20503 And to Mr. Dana O'Hara, Office of Energy Efficiency and Renewable Energy (EE- 2G), U.S...

Ion-molecule reactions: their role in radiation chemistry

International Nuclear Information System (INIS)

Lias, S.G.; Ausloos, P.

1975-01-01

A comprehensive review of ion--molecule reactions is presented, including information from mass spectrometric, organic chemistry, and NMR studies, from theoretical calculations, and from gas and liquid phase radiation chemistry. Special emphasis is placed on interpreting the role of ion--molecule reactions in systems under high energy irradiation. The discussion is presented under the following chapter headings: ion--molecule reactions and their role in radiation chemistry; unimolecular processes: the nature and structure of ionic intermediates in radiolysis; ion lifetimes and the fate of unreactive ions; kinetics and mechanisms of ion--molecule reactions; proton transfer reactions; negative atom and two-atom transfer reactions; condensation reactions; and, association or clustering reactions

Handbook on process and chemistry on nuclear fuel reprocessing

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Atsuyuki (ed.) [Tokyo Univ., Tokyo (Japan); Asakura, Toshihide; Adachi, Takeo (eds.) [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] [and others

2001-12-01

'Wet-type' nuclear fuel reprocessing technology, based on PUREX technology, has wide applicability as the principal reprocessing technology of the first generation, and relating technologies, waste management for example, are highly developed, too. It is quite important to establish a database summarizing fundamental information about the process and the chemistry of 'wet-type' reprocessing, because it contributes to establish and develop fuel reprocessing process and nuclear fuel cycle treating high burn-up UO{sub 2} fuel and spent MOX fuel, and to utilize 'wet-type' reprocessing technology much widely. This handbook summarizes the fundamental data on process and chemistry, which was collected and examined by 'Editing Committee of Handbook on Process and Chemistry of Nuclear Fuel Reprocessing', from FY 1993 until FY 2000. (author)

Proceedings of DAE-BRNS third international symposium on materials chemistry

International Nuclear Information System (INIS)

Tyagi, Deepak; Banerjee, Atindra Mohan; Nigam, Sandeep; Varma, Salil; Tripathi, Arvind Kumar; Bharadwaj, Shyamala Rajkumar; Das, Dasarathi

2010-12-01

The present volume consists of the proceedings of the DAE-BRNS Third International Symposium on Materials Chemistry. In order to keep pace with the advancements made in the area of materials chemistry, new topics like materials for energy conversion, biomaterials, carbon based materials, soft condensed materials, thin films, surface chemistry, polymer based materials, organic and organometallics, magnetic materials and high purity materials have been included in this symposium while topics like nuclear materials, nanomaterials and clusters, catalysis, chemical sensors, fuel cell materials and computational research in materials chemistry have been continued as important features of the symposium. Papers relevant to INIS are indexed separately

Heterogenous phase as a mean in combinatorial chemistry

International Nuclear Information System (INIS)

Abdel-Hamid, S.G.

2007-01-01

Combinatorial chemistry is a rapid and inexpensive technique for the synthesis of hundreds of thousands of organic compounds of potential medicinal activity. In the past few decades a large number of combinatorial libraries have been constructed, and significantly supplement the chemical diversity of the traditional collections of the potentially active medicinal compounds. Solid phase synthesis was used to enrich the combinatorial chemistry libraries, through the use of solid supports (resins) and their modified forms. Most of the new libraries of compounds appeared recently, were synthesized by the use of solid-phase. Solid-phase combinatorial chemistry (SPCC) is now considered as an outstanding branch in pharmaceutical chemistry research and used extensively as a tool for drug discovery within the context of high-throughput chemical synthesis. The best pure libraries synthesized by the use of solid phase combinatorial chemistry (SPCC) may well be those of intermediate complexity that are free of artifact-causing nuisance compounds. (author)

The Materials Chemistry of Atomic Oxygen with Applications to Anisotropic Etching of Submicron Structures in Microelectronics and the Surface Chemistry Engineering of Porous Solids

Science.gov (United States)

Koontz, Steve L.; Leger, Lubert J.; Wu, Corina; Cross, Jon B.; Jurgensen, Charles W.

1994-01-01

Neutral atomic oxygen is the most abundant component of the ionospheric plasma in the low Earth orbit environment (LEO; 200 to 700 kilometers altitude) and can produce significant degradation of some spacecraft materials. In order to produce a more complete understanding of the materials chemistry of atomic oxygen, the chemistry and physics of O-atom interactions with materials were determined in three radically different environments: (1) The Space Shuttle cargo bay in low Earth orbit (the EOIM-3 space flight experiment), (2) a high-velocity neutral atom beam system (HVAB) at Los Alamos National Laboratory (LANL), and (3) a microwave-plasma flowing-discharge system at JSC. The Space Shuttle and the high velocity atom beam systems produce atom-surface collision energies ranging from 0.1 to 7 eV (hyperthermal atoms) under high-vacuum conditions, while the flowing discharge system produces a 0.065 eV surface collision energy at a total pressure of 2 Torr. Data obtained in the three different O-atom environments referred to above show that the rate of O-atom reaction with polymeric materials is strongly dependent on atom kinetic energy, obeying a reactive scattering law which suggests that atom kinetic energy is directly available for overcoming activation barriers in the reaction. General relationships between polymer reactivity with O atoms and polymer composition and molecular structure have been determined. In addition, vacuum ultraviolet photochemical effects have been shown to dominate the reaction of O atoms with fluorocarbon polymers. Finally, studies of the materials chemistry of O atoms have produced results which may be of interest to technologists outside the aerospace industry. Atomic oxygen 'spin-off' or 'dual use' technologies in the areas of anisotropic etching in microelectronic materials and device processing, as well as surface chemistry engineering of porous solid materials are described.

Progress in physical chemistry

CERN Document Server

Hempelmann, Rolf

2008-01-01

Progress in Physical Chemistry is a collection of recent ""Review Articles"" published in the ""Zeitschrift für Physikalische Chemie"". The second volume of Progress in Physical Chemistry is a collection of thematically closely related minireview articles written by the members of the Collaborative Research Centre (SFB) 277 of the German Research Foundation (DFG). These articles are based on twelve years of intense coordinated research efforts. Central topics are the synthesis and the characterization of interface-dominated, i.e. nanostructured materials, mainly in the solid state but also as

Single event upset and charge collection measurements using high energy protons and neutrons

International Nuclear Information System (INIS)

Normand, E.; Oberg, D.L.; Wert, J.L.; Ness, J.D.; Majewski, P.P.; Wender, S.; Gavron, A.

1994-01-01

RAMs, microcontrollers and surface barrier detectors were exposed to beams of high energy protons and neutrons to measure the induced number of upsets as well as energy deposition. The WNR facility at Los Alamos provided a neutron spectrum similar to that of the atmospheric neutrons. Its effect on devices was compared to that of protons with energies of 200, 400, 500, and 800 MeV. Measurements indicate that SEU cross sections for 400 MeV protons are similar to those induced by the atmospheric neutron spectrum

Collective processes in a tokamak with high-energy particles: general problems of the linear theory of Alfven instabilities of a tokamak with high-energy ions

International Nuclear Information System (INIS)

Mikhailovskii, A.B.

1986-01-01

Some general problems of the theory of Alfven instabilities of a tokamak with high-energy ions are considered. It is assumed that such ions are due to either ionization of fast neutral atoms, injected into the tokamak, or production of them under thermo-nuclear conditions. Small-oscillation equations are derived for the Alfven-type waves, which allow for both destabilizing effects, associated with the high-energy particles, and stabilizing ones, such as effects of shear and bulk-plasm dissipation. A high-energy ion contribution is calculated into the growth rate of the Alfven waves. The author considers the role of trapped-electron collisional dissipation

Study on high concentration solar concentrator using a Fresnel lens with a secondary concentrator; Fresnel lens to niji shukokei wo mochiita solar chemistry yo kobairitsu shukokei ni kansuru kenkyu

Energy Technology Data Exchange (ETDEWEB)

Aihara, T; Suzuki, A; Fujibayashi, K [Tokyo University of Agriculture and Technology, Tokyo (Japan)

1997-11-25

A high concentration light collection system for solar chemistry was devised by using an inexpensive Fresnel lens in a primary concentration system and a conical type concentrator in a secondary concentration system. A Fresnel lens alone would not achieve sufficiently high light collecting magnification to attain high temperatures because of restrictions in the opening angle as seen from a focus. Therefore, a secondary concentration system was installed on a focus for an attempt of stopping. Reflection plane of a three-dimensional compound parabolic concentrator (CPC) is a rotary parabolic plane, whose process is expensive because of its surface processing accuracy. Therefore, a conical type concentrator was employed as a secondary concentration system. This system may not be capable of achieving as high concentration as in the CPC, but its shape is simple and it is inexpensive. In its optimization, a complete black body surface placed in vacuum atmosphere was hypothesized as a light concentrating part for the secondary concentration system to calculate heat collecting efficiencies at respective temperature settings. Using simultaneously the secondary concentration system, rather than collecting heat by using a Fresnel lens alone, has attained as high value as from 5.99% (500 degC) to 43.47% (1400 degC). Economical high-temperature heat collection of solar chemistry level may be possible by using a Fresnel lens and a conical secondary concentration system. 1 ref., 7 figs., 2 tabs.

Zambian Pre-Service Chemistry Teachers' Views on Chemistry Education Goals and Challenges for Achieving Them in Schools

Science.gov (United States)

Banda, Asiana; Mumba, Frackson; Chabalengula, Vivien M.

2014-01-01

This study examined Zambian preservice chemistry teachers' views on the goals of chemistry education, the importance of the goals, and challenges for achieving them in schools. The study sample was comprised of 59 pre-service chemistry teachers at the University of Zambia. Data were collected using a modified Likert-scale questionnaire that was…

11th National Meeting of Organic Chemistry and 4th Meeting of Therapeutic Chemistry

Science.gov (United States)

Sousa, Maria Emília; Araújo, Maria João; do Vale, Maria Luísa; Andrade, Paula B.; Branco, Paula; Gomes, Paula; Moreira, Rui; Pinho e Melo, Teresa M.V.D.; Freitas, Victor

2016-01-01

For the first time under the auspices of Sociedade Portuguesa de Química, the competences of two important fields of Chemistry are brought together into a single event, the 11st National Organic Chemistry Meeting and the the 4th National Medicinal Chemistry Meeting, to highlight complementarities and to promote new synergies. Abstracts of plenary lectures, oral communications, and posters presented during the meeting are collected in this report. PMID:27102166

11th National Meeting of Organic Chemistry and 4th Meeting of Therapeutic Chemistry

Directory of Open Access Journals (Sweden)

Maria Emília Sousa

2016-03-01

Full Text Available For the first time under the auspices of Sociedade Portuguesa de Química, the competences of two important fields of Chemistry are brought together into a single event, the 11st National Organic Chemistry Meeting and the the 4th National Medicinal Chemistry Meeting, to highlight complementarities and to promote new synergies. Abstracts of plenary lectures, oral communications, and posters presented during the meeting are collected in this report.

Assessing Advanced High School and Undergraduate Students' Thinking Skills: The Chemistry--From the Nanoscale to Microelectronics Module

Science.gov (United States)

Dori, Yehudit Judy; Dangur, Vered; Avargil, Shirly; Peskin, Uri

2014-01-01

Chemistry students in Israel have two options for studying chemistry: basic or honors (advanced placement). For instruction in high school honors chemistry courses, we developed a module focusing on abstract topics in quantum mechanics: Chemistry--From the Nanoscale to Microelectronics. The module adopts a visual-conceptual approach, which…

Advanced radiation chemistry research: Current status

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-10-01

Radiation chemistry is a branch of chemistry that studies chemical transformations in materials exposed to high-energy radiations. It is based on the use of ionizing radiation as the initiator or catalyst in chemical reactions. The most significant advantage of radiation chemistry lies in its ability to be used in the production and study of almost any reactive atomic and molecular species playing a part in chemical reaction, synthesis, industrial processes, or in biological systems. Over the the last few years a number of meetings have taken place, under the auspices of the IAEA, in order to evaluate recent developments in radiation chemistry as well as the trends indicated by the results obtained. Radiation chemists from different countries have participated at these meetings. The present publication, a companion to the previous publication - New Trends and Development in Radiation Chemistry, IAEA-TECDOC-527 (1989) - includes some of the important contributions presented at these meetings. It is hoped that it will provide a useful overview of current activities and of emerging trends in this field, thus promoting better understanding of potential contributions of radiation chemistry to other fields of knowledge as well as to practical applications in industry, medicine and agriculture. Refs, figs and tabs.

Advanced radiation chemistry research: Current status

International Nuclear Information System (INIS)

1995-10-01

Radiation chemistry is a branch of chemistry that studies chemical transformations in materials exposed to high-energy radiations. It is based on the use of ionizing radiation as the initiator or catalyst in chemical reactions. The most significant advantage of radiation chemistry lies in its ability to be used in the production and study of almost any reactive atomic and molecular species playing a part in chemical reaction, synthesis, industrial processes, or in biological systems. Over the the last few years a number of meetings have taken place, under the auspices of the IAEA, in order to evaluate recent developments in radiation chemistry as well as the trends indicated by the results obtained. Radiation chemists from different countries have participated at these meetings. The present publication, a companion to the previous publication - New Trends and Development in Radiation Chemistry, IAEA-TECDOC-527 (1989) - includes some of the important contributions presented at these meetings. It is hoped that it will provide a useful overview of current activities and of emerging trends in this field, thus promoting better understanding of potential contributions of radiation chemistry to other fields of knowledge as well as to practical applications in industry, medicine and agriculture. Refs, figs and tabs

Using Graphs of Gibbs Energy versus Temperature in General Chemistry Discussions of Phase Changes and Colligative Properties

Science.gov (United States)

Hanson, Robert M.; Riley, Patrick; Schwinefus, Jeff; Fischer, Paul J.

2008-01-01

The use of qualitative graphs of Gibbs energy versus temperature is described in the context of chemical demonstrations involving phase changes and colligative properties at the general chemistry level. (Contains 5 figures and 1 note.)

Chemistry in protoplanetary disks

Science.gov (United States)

Semenov, D. A.

2012-01-01

In this lecture I discuss recent progress in the understanding of the chemical evolution of protoplanetary disks that resemble our Solar system during the first ten million years. At the verge of planet formation, strong variations of temperature, density, and radiation intensities in these disks lead to a layered chemical structure. In hot, dilute and heavily irradiated atmosphere only simple radicals, atoms, and atomic ions can survive, formed and destroyed by gas-phase processes. Beneath the atmosphere a partly UV-shielded, warm molecular layer is located, where high-energy radiation drives rich chemistry, both in the gas phase and on dust surfaces. In a cold, dense, dark disk midplane many molecules are frozen out, forming thick icy mantles where surface chemistry is active and where complex (organic) species are synthesized.

High energy halogen atom reactions activated by nuclear transformations. Progress report, February 15, 1978--February 14, 1979

International Nuclear Information System (INIS)

Rack, E.P.

1979-02-01

High energy reactions of halogen atoms or ions, activated by nuclear transformations, were studied in gaseous, high pressure and condensed phase saturated and unsaturated hydrocarbons, halomethanes and other organic systems in order to better understand the mechanisms and dynamics of high energy monovalent species. The experimental and theoretical program consists of six interrelated areas: (1) the reactions of iodine with alkenes and alkynes activated by radiative neutron capture and isomeric transition in low pressure gaseous systems employing additives and rare gas moderators, high pressure and liquid systems; (2) the gas to condensed state transition in halogen high chemistry, involving bromine activated by the (n,γ) and (I.T.) processes in ethane was investigated in more detail; (3) systematics of halogen hot atom reactions. The reactions of 80 Br/sup m/, 80 Br, 82 Br/sup m/ + 82 Br, 82 Br, 128 I, 130 I, and 130 I/sup m/ + 130 I activated by radiative neutron capture or isomeric transition in hydrocarbons and halo-substituted alkanes in low pressure and high pressure gaseous systems employing additives and rare gas moderators; (4) kinetic theory applications of high energy reactions and mathematical development of caging mechanisms were developed; (5) the sterochemistry of 38 Cl substitution reactions involving diastereomeric 1,2-dichloro-1,2-difluorethane in liquid mixtures was completed, suggesting that the stereochemical course of the substitution process is controlled by the properties of the solvent molecules; and (6) the applications of high energy chemistry techniques and theory to neutron activation analysis of biological systems was continued, especially involving aluminum and vanadium trace determinations

Scheme of energy collective services; Schema de services collectifs de l'energie

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

The scheme of collective energy services aims at facilitating and valorizing the contribution of the national organizations to the national energy plan and to the durable development of the country. The scheme comprises three main goals: defining the exploitation goals of local renewable energy resources and the goals of rational energy uses which can contribute to the national energy independence, to the security of supplies and to the abatement of the greenhouse effect; evaluating the foreseeable energy needs of regions and their energy production potentiality, their energy saving possibilities and their energy transportation needs; and finally, determining the conditions in which the government and the national organizations will be able to favor the energy saving actions and the production and use of renewable energies taking into account their impact on employment and their long-term financial consequences. This document is organized in five parts: 1 - status, stakes and perspectives: energy demand perspectives at the 2010-2020 vista, potentialities of energy saving and renewable energy sources development, implication of the international commitment of France in the fight against greenhouse effect; 2 - action means for new measures: buildings and accommodations, transportation sector, industry sector, mastery of electricity demand, development of renewable energy sources, decentralized energy production, energy storage, transport and distribution, economic tools and public means of sustain; 3 - follow up of the scheme of energy collective services; 4 - analysis of regional contributions; 5 - appendixes and maps. (J.S.)

High energy halogen atom reactions activated by nuclear transformations. Progress report, February 15, 1980-February 14, 1981

International Nuclear Information System (INIS)

1981-02-01

The stereochemistry of high energy 18 F, /sup 34m/Cl, and 76 Br substitution reactions involving enantiomeric molecules in the gas and condensed phase is studied. The gas to condensed state transition in halogen high energy chemistry, involving chlorine, bromine, and iodine activated by the (n,γ) and (I.T.) processes in halomethanes, saturated and unsaturated hydrocarbons is being investigated in more detail. Special attention is given to defining the nature of the enhancement yields in the condensed phase. High energy halogen reactions in liquid and frozen aqueous solutions of organic and biomolecular solutes are studied in an attempt to learn more about these reactions. The applications of high energy chemistry techniques and theory to neutron activation analysis of biological systems are being continued. Special attention is given to developing procedures for trace molecular determinations in biological systems. The applications of hot halogen atoms as indicators of solute-solute interactions in liquid and frozen aqueous solutions of halogenated bases and nucleosides are being developed. Experiments are designed to explain the mechanisms of the radioprotection offered biomolecular solutes trapped within the frozen ice lattice. Reactions of bromine and iodine activated by isomeric transition with halogenated biomolecular solutes in liquid and frozen aqueous solutions are studied. The high energy reactions of iodine with the isomers of pentene have been studied in low pressure gaseous systems employing additives and rare gas moderators and liquid systems. Reactivity of excited complex formation and structural effects of electrophilic iodine attack on the pi-bond systems are studied

High energy halogen atom reactions activated by nuclear transformations. Progress report, February 15, 1980-February 14, 1981

Energy Technology Data Exchange (ETDEWEB)

1981-02-01

The stereochemistry of high energy /sup 18/F, /sup 34m/Cl, and /sup 76/Br substitution reactions involving enantiomeric molecules in the gas and condensed phase is studied. The gas to condensed state transition in halogen high energy chemistry, involving chlorine, bromine, and iodine activated by the (n,..gamma..) and (I.T.) processes in halomethanes, saturated and unsaturated hydrocarbons is being investigated in more detail. Special attention is given to defining the nature of the enhancement yields in the condensed phase. High energy halogen reactions in liquid and frozen aqueous solutions of organic and biomolecular solutes are studied in an attempt to learn more about these reactions. The applications of high energy chemistry techniques and theory to neutron activation analysis of biological systems are being continued. Special attention is given to developing procedures for trace molecular determinations in biological systems. The applications of hot halogen atoms as indicators of solute-solute interactions in liquid and frozen aqueous solutions of halogenated bases and nucleosides are being developed. Experiments are designed to explain the mechanisms of the radioprotection offered biomolecular solutes trapped within the frozen ice lattice. Reactions of bromine and iodine activated by isomeric transition with halogenated biomolecular solutes in liquid and frozen aqueous solutions are studied. The high energy reactions of iodine with the isomers of pentene have been studied in low pressure gaseous systems employing additives and rare gas moderators and liquid systems. Reactivity of excited complex formation and structural effects of electrophilic iodine attack on the pi-bond systems are studied.

Distributed scaffolding: Wiki collaboration among Latino high school chemistry students

Science.gov (United States)

O'Sullivan, Edwin Duncan, Jr.

The primary purpose of this study was to evaluate if wiki collaboration among Latino high school chemistry students can help reduce the science achievement gap between Latino and White students. The study was a quasi-experimental pre/post control group mixed-methods design. It used three intact sections of a high school chemistry course. The first research question asked if there is a difference in academic achievement between a treatment and control group on selected concepts from the topics of bonding, physical changes, and chemical changes, when Latino high school chemistry students collaborate on a quasi-natural wiki project. Overall results for all three activities (Bonding, Physical Changes, and Chemical Changes) indicated no significant difference between the wiki and control group. However, students performing the chemical changes activity did significantly better than their respective control group. Furthermore, there was a significant association, with large effect size, between group membership and ability to overcome the misconception that aqueous ionic reactants in precipitation reactions exist as molecular pairs of ions. Qualitative analysis of classroom and computer lab dialogue, discussion board communication, student focus groups, teacher interviews, and wiki content attributes the better performance of the chemical changes wiki group to favorable differences in intersubjectivity and calibrated assistance, as well as learning about submicroscopic representations of precipitation reactions in multiple contexts. Furthermore, the nonsignificant result overall points to an aversion to peer editing as a possible cause. Drawing considerably on Vygotsky and Piaget, the results are discussed within the context of how distributed scaffolding facilitated medium levels of cognitive conflict. The second research question asked what the characteristics of distributed metacognitive scaffolding are when Latino high school chemistry students collaborate on a quasi

Techno-economic analysis of a wind-solar hybrid renewable energy system with rainwater collection feature for urban high-rise application

International Nuclear Information System (INIS)

Chong, W.T.; Naghavi, M.S.; Poh, S.C.; Mahlia, T.M.I.; Pan, K.C.

2011-01-01

Graphical abstract: This wind-solar hybrid renewable energy system is a new concept of the utilization, integration and optimization of existing renewable energy and rain water harvesting technologies. It is compact and can be built on the top of high rise buildings to provide on-site green power to that building or feed into the grid line. This system utilizes the advantages of Malaysian climate, i.e. high solar radiation and rainfall for green energy generation and free water supply. It also overcomes the inferior aspect on the low wind speed by guiding and increasing the speed of the high altitude free-stream wind from all directions radially through power-augmentation-guide-vane (PAGV) before entering the wind turbine at center portion. The PAGV is an innovative design used to guide and create venturi effect to increase the wind speed before the wind-stream enters wind turbine. The system must also be designed to provide optimum surface area for solar panel (solar thermal or photovoltaic or solar PV/T)) installation and battery compartment for power storage. In addition; rain water collection feature must be built-into the system design. The system is recommended to be sited on the top of high rise buildings or structures with its appearance or outer design can be blended into the building architecture without negative visual impact. With this system, the size of wind turbine can be reduced for a given power output and the noise is also reduced since it is contained in the PAGV. The design is also safer and suitable to be used in populated area. Mesh can be mounted at the entrance of the PAGV to prevent the bird-strike. This system can eliminate or minimize the current problems concerning public acceptance of wind energy, i.e. poor starting behavior in low wind speed, noise, visual impact, electromagnetic interference, safety and environmental factors. Highlights: → This wind, solar and rain harvester integrates existing renewable energy and rain water

Attitudes towards chemistry among engineering students

Science.gov (United States)

Olivo Delgado, Carlos J.

The attitudes towards chemistry of the engineering students enrolled in an introductory course at the Polytechnic University of Puerto Rico were explored (n = 115). A mixed methodology was used in an exploratory-oriented research approach. The first stage consisted of the administration of a Likert scale attitudinal survey which was validated during the study's design process. The survey allowed collecting information about the participant's attitudes towards their personal opinion, their perspectives about peer's or relatives' opinion, relevant aspects of the discipline, and difficulty-increasing factors in the chemistry course. The scale internal reliability was measured in a pilot study with a convenience simple, obtaining an acceptable coefficient (Cronbach alpha = 0.731). Survey results evidenced a mainly neutral attitude towards the chemistry course, not highly negative or highly positive, in contrast with other studies in this field. On the other hand, the normality hypothesis was tested for the scores obtained by participants in the survey. Although the pilot study sample had an approximately normal distribution, the scores in obtained by the participants in the survey failed the normality test criteria. The second stage of the study was accomplished using a case study. Among the survey participants, some students were invited to in-depth interviews to elucidate the reasons why they have certain attitudes towards chemistry. Study time, instructor, motivation, term of study, and course schedule are the factors that interviewees agreed as contributors to success or failure in the chemistry course. Interview's participants emphasized that study time is determinant to pass the class. This methodological approach, quantitative followed by qualitative, was useful in describing the attitudes towards chemistry among university students of engineering.

Opportunistic Sensor Data Collection with Bluetooth Low Energy.

Science.gov (United States)

Aguilar, Sergio; Vidal, Rafael; Gomez, Carles

2017-01-23

Bluetooth Low Energy (BLE) has gained very high momentum, as witnessed by its widespread presence in smartphones, wearables and other consumer electronics devices. This fact can be leveraged to carry out opportunistic sensor data collection (OSDC) in scenarios where a sensor node cannot communicate with infrastructure nodes. In such cases, a mobile entity (e.g., a pedestrian or a vehicle) equipped with a BLE-enabled device can collect the data obtained by the sensor node when both are within direct communication range. In this paper, we characterize, both analytically and experimentally, the performance and trade-offs of BLE as a technology for OSDC, for the two main identified approaches, and considering the impact of its most crucial configuration parameters. Results show that a BLE sensor node running on a coin cell battery can achieve a lifetime beyond one year while transferring around 10 Mbit/day, in realistic OSDC scenarios.

LAT Perspectives in Detection of High Energy Cosmic Ray Electrons

International Nuclear Information System (INIS)

Moiseev, Alexander; Ormes, J.F.; Funk, Stefan

2007-01-01

The LAT science objectives and capabilities in the detection of high energy electrons in the energy range from 20 GeV to ∼1.5 TeV are presented. LAT simulations are used to establish the event selections. It is found that maintaining the efficiency of electron detection at the level of 30%, the residual hadron contamination does not exceed 2-3% of the electron flux. It is expected to collect ∼ ten million of electrons with the energy above 20 GeV for one year of observation. Precise spectrum reconstruction with collected electron statistics opens the unique opportunity to investigate several important problems such as models of IC radiation, revealing the signatures of nearby sources such as high energy cutoff in the electron spectrum, testing the propagation model, and search for KKDM particles decay through their contribution to the electron spectrum

From energy-rich phosphate compounds to warfare agents: A review on the chemistry of organic phosphate compounds

Directory of Open Access Journals (Sweden)

Luciano Albino Giusti

2008-12-01

Full Text Available The chemistry of the phosphorus-oxygen bond is widely used in biological systems in many processes, such as energy transduction and the storage, transmission and expression of genetic information, which are essential to living beings in relation to a wide variety of functions. Compounds containing this bond have been designed for many purposes, ranging from agricultural defense systems, in order to increase food production, to nerve agents, for complaining use in warfare. In this review, features related to the chemistry of organic phosphate compounds are discussed, with particular emphasis on the role of phosphate compounds in biochemical events and in nerve agents. To this aim, the energy-rich phosphate compounds are focused, particularly the mode of their use as energy currency in cells. Historical and recent studies carried out by research groups have tried to elucidate the mechanism of action of enzymes responsible for energy transduction through the use of biochemical studies, enzyme models, and artificial enzymes. Finally, recent studies on the detoxification of nerve agents based on phosphorous esters are presented, and on the utilization of chromogenic and fluorogenic chemosensors for the detection of these phosphate species.

Pretreatment data is highly predictive of liver chemistry signals in clinical trials

Directory of Open Access Journals (Sweden)

Cai Z

2012-11-01

Full Text Available Zhaohui Cai,1,* Anders Bresell,2,* Mark H Steinberg,1 Debra G Silberg,1 Stephen T Furlong11AstraZeneca Pharmaceuticals, Wilmington, DE, USA; 2AstraZeneca Pharmaceuticals, Södertälje, Sweden*These authors contributed equally to this workPurpose: The goal of this retrospective analysis was to assess how well predictive models could determine which patients would develop liver chemistry signals during clinical trials based on their pretreatment (baseline information.Patients and methods: Based on data from 24 late-stage clinical trials, classification models were developed to predict liver chemistry outcomes using baseline information, which included demographics, medical history, concomitant medications, and baseline laboratory results.Results: Predictive models using baseline data predicted which patients would develop liver signals during the trials with average validation accuracy around 80%. Baseline levels of individual liver chemistry tests were most important for predicting their own elevations during the trials. High bilirubin levels at baseline were not uncommon and were associated with a high risk of developing biochemical Hy’s law cases. Baseline γ-glutamyltransferase (GGT level appeared to have some predictive value, but did not increase predictability beyond using established liver chemistry tests.Conclusion: It is possible to predict which patients are at a higher risk of developing liver chemistry signals using pretreatment (baseline data. Derived knowledge from such predictions may allow proactive and targeted risk management, and the type of analysis described here could help determine whether new biomarkers offer improved performance over established ones.Keywords: bilirubin, Hy’s Law, ALT, GGT, baseline, prediction

Progress report 1985-1986 Reactor Chemistry Department

International Nuclear Information System (INIS)

1987-12-01

The report of the activities performed by the Reactor Chemistry Department of the National Atomic Energy Commission, during the period 1985-1986, covers works of investigation, development and service related to the Argentine Nuclear Power Plants. The main subjects are the experimental and theoretical studies about physical chemistry and chemistry control at the moderators and heat transport system of the nuclear power plants. The more relevant topics are related to: 1: Behaviour of gases, electrolites and other additives for nuclear power plants, at high temperature and pressure; 2: Ionic exchangers of nuclear degree; 3: Electrochemistry studies connected with the constitutive materials' corrosion and with the nuclear power plants decontamination processes; 4: Behaviour of suspensions and colloids in nuclear power plants; 5: Use of new additives for chemistry control of the oxides which are in the circuits of nuclear power plants; 6: Research methods that allow to check reactor's control quality; 7: Study of the radiolytic behaviour of nuclear reactor's solutions. (M.E.L.) [es

Proceedings of the DAE-BRNS fourth interdisciplinary symposium on materials chemistry

International Nuclear Information System (INIS)

Tyagi, D.; Banerjee, A.M.; Bhattacharyya, K.; Nigam, S.; Varma, S.; Tripathi, A.K.; Das, D.

2012-12-01

This symposium covers almost all the contemporary research areas of materials chemistry like materials for energy conversion, biomaterials, carbon based materials, chemical sensors, fuel cell materials and other electro-ceramics, polymers and soft condensed matters, thin films and surface chemistry, organic and organometallics, high purity materials, nanomaterials and clusters to acquaint ourselves with the advancement made in these emerging areas. Topics like nuclear materials, magnetic materials, catalysis and computational materials chemistry continue to be important facet of ISMC series of symposia. Papers relevant to INIS are indexed separately

Remarkably High Stability of Late Actinide Dioxide Cations: Extending Chemistry to Pentavalent Berkelium and Californium.

Science.gov (United States)

Dau, Phuong D; Vasiliu, Monica; Peterson, Kirk A; Dixon, David A; Gibson, John K

2017-12-06

Actinyl chemistry is extended beyond Cm to BkO 2 + and CfO 2 + through transfer of an O atom from NO 2 to BkO + or CfO + , establishing a surprisingly high lower limit of 73 kcal mol -1 for the dissociation energies, D[O-(BkO + )] and D[O-(CfO + )]. CCSD(T) computations are in accord with the observed reactions, and characterize the newly observed dioxide ions as linear pentavalent actinyls; these being the first Bk and Cf species with oxidation states above IV. Computations of actinide dioxide cations AnO 2 + for An=Pa to Lr reveal an unexpected minimum for D[O-(CmO + )]. For CmO 2 + , and AnO 2 + beyond EsO 2 + , the most stable structure has side-on bonded η 2 -(O 2 ), as An III peroxides for An=Cm and Lr, and as An II superoxides for An=Fm, Md, and No. It is predicted that the most stable structure of EsO 2 + is linear [O=Es V =O] + , einsteinyl, and that FmO 2 + and MdO 2 + , like CmO 2 + , also have actinyl(V) structures as local energy minima. The results expand actinide oxidation state chemistry, the realm of the distinctive actinyl moiety, and the non-periodic character towards the end of the periodic table. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Annual report of the Osaka Laboratory for Radiation Chemistry Japan Atomic Energy Research Institute, 21

International Nuclear Information System (INIS)

1990-03-01

This report describes research activities of Osaka Laboratory for Radiation Chemistry, JAERI during one year period from April 1, 1987 through March 31, 1988. Detailed descriptions of the activities are presented in the following subjects: (i) studies on surface phenomena under electron and ion irradiations and (ii) studies on radiation chemistry of high polymers and radiation dosimetry. (J.P.N.)

Prompt High Energy Dipole γ Emission

International Nuclear Information System (INIS)

Corsi, A.; Giaz, A; Bracco, A.

2011-01-01

The study of the collective properties of a nuclear system is a powerful tool to understand the structure which lies inside the nucleus. A successful technique which has been used in this field is the measurement of the γ-decay of the highly collective Giant Dipole Resonance (GDR). In fact, GDR can be used as a probe for the internal structure of hot nuclei and, in addition, constitutes a clock for the thermalization process. Using the fusion-evaporation reaction, it has been recently possible to study (i) the yield of the high-energy γ-ray emission of the Dynamical Dipole which takes place during the fusion process and (ii) the degree of isospin mixing at high temperature in the decay of 80 Zr. In the first case it is important to stress the fact that the predictions of the theoretical models might differ depending on the type of nuclear equation of state (EOS) and on the N-N in-medium cross-section used in the calculations while, in the second physics case, the data are relative to the heaviest N = Z nucleus which has been possible to populate in the I = 0 channel using fusion-evaporation reaction. Both experiments were performed at the Laboratori Nazionali di Legnaro using the HECTOR-GARFIELD array. The high-energy γ-rays were measured in coincidence with light charged particles and fusion-evaporation residues. (author)

Energy Conversion & Storage Program, 1993 annual report

Energy Technology Data Exchange (ETDEWEB)

Cairns, E.J.

1994-06-01

The Energy Conversion and Storage Program applies chemistry and materials science principles to solve problems in: production of new synthetic fuels; development of high-performance rechargeable batteries and fuel cells; development of high-efficiency thermochemical processes for energy conversion; characterization of complex chemical processes and chemical species; and the study and application of novel materials for energy conversion and transmission. Projects focus on transport-process principles, chemical kinetics, thermodynamics, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, novel materials, and advanced methods of analysis.

Physics and applications of high energy density plasmas. Extreme state driven by pulsed electromagnetic energy

International Nuclear Information System (INIS)

Horioka, Kazuhiko

2002-06-01

The papers presented at the symposium on ''Physics and application of high energy density plasmas, held December 20-21, 2001 at NIFS'' are collected in this proceedings. The topics covered in the meeting include dense z-pinches, plasma focus, intense charged particle beams, intense radiation sources, discharge pumped X-ray lasers, their diagnostics, and applications of them. The papers reflect the present status and trends in the research field of high energy density plasmas. (author)

Constitutional dynamic chemistry: bridge from supramolecular chemistry to adaptive chemistry.

Science.gov (United States)

Lehn, Jean-Marie

2012-01-01

Supramolecular chemistry aims at implementing highly complex chemical systems from molecular components held together by non-covalent intermolecular forces and effecting molecular recognition, catalysis and transport processes. A further step consists in the investigation of chemical systems undergoing self-organization, i.e. systems capable of spontaneously generating well-defined functional supramolecular architectures by self-assembly from their components, thus behaving as programmed chemical systems. Supramolecular chemistry is intrinsically a dynamic chemistry in view of the lability of the interactions connecting the molecular components of a supramolecular entity and the resulting ability of supramolecular species to exchange their constituents. The same holds for molecular chemistry when the molecular entity contains covalent bonds that may form and break reversibility, so as to allow a continuous change in constitution by reorganization and exchange of building blocks. These features define a Constitutional Dynamic Chemistry (CDC) on both the molecular and supramolecular levels.CDC introduces a paradigm shift with respect to constitutionally static chemistry. The latter relies on design for the generation of a target entity, whereas CDC takes advantage of dynamic diversity to allow variation and selection. The implementation of selection in chemistry introduces a fundamental change in outlook. Whereas self-organization by design strives to achieve full control over the output molecular or supramolecular entity by explicit programming, self-organization with selection operates on dynamic constitutional diversity in response to either internal or external factors to achieve adaptation.The merging of the features: -information and programmability, -dynamics and reversibility, -constitution and structural diversity, points to the emergence of adaptive and evolutive chemistry, towards a chemistry of complex matter.

Network analysis reveals multiscale controls on streamwater chemistry

Science.gov (United States)

Kevin J. McGuire; Christian E. Torgersen; Gene E. Likens; Donald C. Buso; Winsor H. Lowe; Scott W. Bailey

2014-01-01

By coupling synoptic data from a basin-wide assessment of streamwater chemistry with network-based geostatistical analysis, we show that spatial processes differentially affect biogeochemical condition and pattern across a headwater stream network. We analyzed a high-resolution dataset consisting of 664 water samples collected every 100 m throughout 32 tributaries in...

Analytical Chemistry Laboratory. Progress report for FY 1996

Energy Technology Data Exchange (ETDEWEB)

Green, D.W.; Boparai, A.S.; Bowers, D.L.

1996-12-01

The purpose of this report is to summarize the activities of the Analytical Chemistry Laboratory (ACL) at Argonne National Laboratory (ANL) for Fiscal Year (FY) 1996. This annual report is the thirteenth for the ACL. It describes effort on continuing and new projects and contributions of the ACL staff to various programs at ANL. The ACL operates in the ANL system as a full-cost-recovery service center, but has a mission that includes a complementary research and development component: The Analytical Chemistry Laboratory will provide high-quality, cost-effective chemical analysis and related technical support to solve research problems of our clients -- Argonne National Laboratory, the Department of Energy, and others -- and will conduct world-class research and development in analytical chemistry and its applications. Because of the diversity of research and development work at ANL, the ACL handles a wide range of analytical chemistry problems. Some routine or standard analyses are done, but the ACL usually works with commercial laboratories if our clients require high-volume, production-type analyses. It is common for ANL programs to generate unique problems that require significant development of methods and adaption of techniques to obtain useful analytical data. Thus, much of the support work done by the ACL is very similar to our applied analytical chemistry research.

An overview of the teaching of nuclear chemistry

International Nuclear Information System (INIS)

Seaborg, G.I.

1990-01-01

Otto Hahn's book, Applied Radiochemistry, published in 1936, marked the author's entry into this field. Notes concerning a lecture course, An Introduction to Nuclear Chemistry, given during the summer of 1942 at the University of Chicago, as an introduction to the Plutonium Project of the Manhattan District, were widely distributed for use by participants in the Project. Nuclear chemistry courses, undergraduate and graduate, instigated at Berkeley in 1946, were taken by large numbers of students many of who became pioneers in the field. Noteworthy is Friedlander's and Kennedy's 1949 textbook, Introduction to Radiochemistry (and subsequent revisions). These courses and this book serve as typical examples, many other such courses were taught and books published during the intervening years. More recently the Department of Energy Summer School in Nuclear Chemistry (for high school students) at San Jose State University has helped to revive student interest in nuclear chemistry

Opportunistic Sensor Data Collection with Bluetooth Low Energy

Directory of Open Access Journals (Sweden)

Sergio Aguilar

2017-01-01

Full Text Available Bluetooth Low Energy (BLE has gained very high momentum, as witnessed by its widespread presence in smartphones, wearables and other consumer electronics devices. This fact can be leveraged to carry out opportunistic sensor data collection (OSDC in scenarios where a sensor node cannot communicate with infrastructure nodes. In such cases, a mobile entity (e.g., a pedestrian or a vehicle equipped with a BLE-enabled device can collect the data obtained by the sensor node when both are within direct communication range. In this paper, we characterize, both analytically and experimentally, the performance and trade-offs of BLE as a technology for OSDC, for the two main identified approaches, and considering the impact of its most crucial configuration parameters. Results show that a BLE sensor node running on a coin cell battery can achieve a lifetime beyond one year while transferring around 10 Mbit/day, in realistic OSDC scenarios.

High pressure in solid state chemistry: Combined experimental and modeling approaches for assessing and predicting properties

Science.gov (United States)

Etourneau, Jean; Matar, Samir F.

2018-06-01

The thermodynamic pressure parameter has been thoroughly used with mastership by Gérard Demazeau throughout his rich career in solid state chemistry and materials sciences and more recently in biosciences. After a review of such works, focus is made in this topical article on his contribution together with his team in the field of hard materials based on light elements B, C, N with a proposition of a new ultra-hard carbon nitride C2N on one hand and on the structural transformations under high pressures of perovskite into postperovskite with a change of dimensionality from 3D to 2D and related oxides, regarding the arrangement of octahedra, on the other hand. Investigation and concepts first arising from experimental observables are shown to be aided and accelerated via first principles calculations of energy and energy-related quantities.

Complex fluids, divided solids and their interfaces: Open scientific questions addressed at the Institute of Separation Chemistry of Marcoule for a sustainable nuclear energy

International Nuclear Information System (INIS)

Leroy, M.; Henge-Napoli, M.H.; Zemb, Th.

2007-01-01

Key issues in radiochemistry, physical chemistry of separation and chemistry of materials needed for a sustainable nuclear energy production are described. These driving questions are at the origin of the creation of the Institute of Separation Chemistry at Marcoule. Each of the domains has been described extensively in recent reports for science and technology of the French academy of Science. (authors)

Chemistry Teachers' Views of Creativity

Science.gov (United States)

Akkanat, Çigdem; Gökdere, Murat

2015-01-01

The purpose of this study was to determine chemistry teachers' views of creativity. In this study, phenomenology method, one of the qualitative research patterns, was used. The participants of this study were 13 chemistry teachers working in Amasya. A semi-structured interview form was used for data collection. By using NVivo 9 qualitative…

Chemistry management system for nuclear power plants

International Nuclear Information System (INIS)

Nagasawa, Katsumi; Maeda, Katsuji

1998-01-01

Recently, the chemistry management in the nuclear power plants has been changing from the problem solution to the predictive diagnosis and maintenance. It is important to maintain the integrity of plant operation by an adequate chemistry control. For these reasons, many plant operation data and chemistry analysis data should be collected and treated effectively to evaluate chemistry condition of the nuclear power plants. When some indications of chemistry anomalies occur, quick and effective root cause evaluation and countermeasures should be required. The chemistry management system has been developed as to provide sophisticate chemistry management in the nuclear power plants. This paper introduces the concept and functions of the chemistry management system for the nuclear power plants. (author)

A high-speed beam of lithium droplets for collecting diverted energy and particles in ITER [International Thermonuclear Experimental Reactor

International Nuclear Information System (INIS)

Werley, K.A.

1989-01-01

A high-speed (160m/s) beam (0.14 x 0.86m) of liquid-lithium droplets passing through the divertor region(s) below (and above) the main plasma has the potential to replace and out-perform ''conventional'' solid divertor plates in both heat and particle removal. In addition to superior heat-collection properties, the lithium beam would: remove impurities; require low power to circulate the lithium; exhibit low-recycle divertor operation compatible with lower-hybrid current drive, H-mode plasma confinement, and no flow reversal in the edge plasma; be insensitive to plasma shifts; and finally protect solid structures from the plasma thermal energy for those disruptions that deposit energy preferentially into the divertor while simultaneously being rapidly re-established after a major disruption. Scoping calculations identifying the beam configuration and the droplet dynamics, including formation, MHD effects, gravitational effects, thermal response and hydrodynamics, are presented. Limitations and uncertainties are also discussed. 20 refs., 6 figs., 3 tabs

Primary processes in radiation chemistry. LET (Linear Energy Transfer) effect in water radiolysis

International Nuclear Information System (INIS)

Trupin-Wasselin, V.

2000-01-01

The effect of ionizing radiations on aqueous solutions leads to water ionization and then to the formation of radical species and molecular products (e - aq , H . , OH . , H 2 O 2 , H 2 ). It has been shown that the stopping power, characterized by the LET value (Linear Energy Transfer) becomes different when the nature of the ionizing radiations is different. Few data are nowadays available for high LET radiations such as protons and high energy heavy ions. These particles have been used to better understand the primary processes in radiation chemistry. The yield of a chemical dosimeter (the Fricke dosimeter) and those of the hydrogen peroxide have been determined for different LET. The effect of the dose rate on the Fricke dosimeter yield and on the H 2 O 2 yield has been studied too. When the dose rate increases, an increase of the molecular products yield is observed. At very high dose rate, this yield decreases on account of the attack of the molecular products by radicals. The H 2 O 2 yield in alkaline medium decreases when the pH reaches 12. This decrease can be explained by a slowing down of the H 2 O 2 formation velocity in alkaline medium. Superoxide radical has also been studied in this work. A new detection method: the time-resolved chemiluminescence has been perfected for this radical. This technique is more sensitive than the absorption spectroscopy. Experiments with heavy ions have allowed to determine the O 2 .- yield directly in the irradiation cell. The experimental results have been compared with those obtained with a Monte Carlo simulation code. (O.M.)

Mass spectrometry applied to high temperature chemistry, (2)

International Nuclear Information System (INIS)

Asano, Mitsuru; Kato, Eiichi; Sata, Toshiyuki.

1980-01-01

The application of mass spectrometry to high temperature chemistry is reviewed. As a blanket material for fusion reactors, the behavior of lithium has been investigated by using mass analysers. The enthalpies of the chemical reactions of metallic lithium were obtained. The enthalpies of isomolecular exchange reactions and the derived atomization energies of LiD, Li 2 D and Li 2 D 2 were also obtained by mass spectrometry. The thermomechanical character of lithium oxide was studied. The vaporization behaviors of LiCrO 2 and Li 5 FeO 4 were studied with a quadrupole mass analyser. The vaporization of cobalt from nickel alloy was studied. The evaporated ions were analysed with a mass analyser. The measurement of the vaporized molecules of metals and fused silicate was made by mass spectrometry. The activities of Fe-V system were determined by measuring the ion current ratio. The activities of Fe-V-Cr system were also obtained. The vapor pressure of phosphor from Fe-P alloys can be measured. The activity coefficients and interaction parameters for the dilute solutions of elements, such as Mn, Al, Cu, Cr, Co, Ni, Si, Ti, V, B, Zr, Mo, C, S, and P, dissolved in liquid iron are shown in a table. The activities of NaCl-KCl system were derived by measuring the ion current ratio and by monomer-dimer method. (Kato, T.)

Reticular Chemistry and Metal-Organic Frameworks: Design and Synthesis of Functional Materials for Clean Energy Applications

KAUST Repository

Alezi, Dalal A.

2017-06-01

Gaining control over the assembly of crystalline solid-state materials has been significantly advanced through the field of reticular chemistry and metal organic frameworks (MOFs). MOFs have emerged as a unique modular class of porous materials amenable to a rational design with targeted properties for given applications. Several design approaches have been deployed to construct targeted functional MOFs, where desired structural and geometrical attributes are incorporated in preselected building units prior to the assembly process. This dissertation illustrates the merit of the molecular building block approach (MBB) for the rational construction and discovery of stable and highly porous MOFs, and their exploration as potential gas storage medium for sustainable and clean energy applications. Specifically, emphasis was placed on gaining insights into the structure-property relationships that impact the methane (CH4) storage in MOFs and its subsequent delivery. The foreseen gained understanding is essential for the design of new adsorbent materials or adjusting existing MOF platforms to encompass the desired features that subsequently afford meeting the challenging targets for methane storage in mobile and stationary applications.In this context, we report the successful use of the MBB approach for the design and deliberate construction of a series of novel isoreticular, highly porous and stable, aluminum based MOFs with the square-octahedral (soc) underlying net topology. From this platform, Al-soc-MOF-1, with more than 6000 m2/g apparent Langmuir specific surface area, exhibits outstanding gravimetric CH4 uptake (total and working capacities). It is shown experimentally, for the first time, that the Al-soc-MOF platform can address the U.S. Department of Energy (DOE) challenging gravimetric and volumetric targets for the CH4 working capacity for on-board CH4 storage. Furthermore, Al-soc-MOF-1 exhibits the highest total gravimetric and volumetric uptake for carbon

Chemistry, the Central Science? The History of the High School Science Sequence

Science.gov (United States)

Sheppard, Keith; Robbins, Dennis M.

2005-01-01

Chemistry became the ''central science'' not by design but by accident in the US high schools. The three important factors, which had their influence on the high school science, are sequenced and their impact on the development of US science education, are mentioned.

Physics and applications of high energy density plasmas. Extreme state driven by pulsed electromagnetic energy

Energy Technology Data Exchange (ETDEWEB)

Horioka, Kazuhiko (ed.)

2002-06-01

The papers presented at the symposium on ''Physics and application of high energy density plasmas, held December 20-21, 2001 at NIFS'' are collected in this proceedings. The topics covered in the meeting include dense z-pinches, plasma focus, intense charged particle beams, intense radiation sources, discharge pumped X-ray lasers, their diagnostics, and applications of them. The papers reflect the present status and trends in the research field of high energy density plasmas. (author)

Chemistry teachers’ understanding of science process skills in relation of science process skills assessment in chemistry learning

Science.gov (United States)

Hikmah, N.; Yamtinah, S.; Ashadi; Indriyanti, N. Y.

2018-05-01

A Science process skill (SPS) is a fundamental scientific method to achieve good knowledge. SPS can be categorized into two levels: basic and integrated. Learning SPS helps children to grow as individuals who can access knowledge and know how to acquire it. The primary outcomes of the scientific process in learning are the application of scientific processes, scientific reasoning, accurate knowledge, problem-solving, and understanding of the relationship between science, technology, society, and everyday life’s events. Teachers’ understanding of SPS is central to the application of SPS in a learning process. Following this point, this study aims to investigate the high school chemistry teachers’ understanding of SPS pertains to their assessment of SPS in chemistry learning. The understanding of SPS is measured from the conceptual and operational aspects of SPS. This research uses qualitative analysis method, and the sample consists of eight chemistry teachers selected by random sampling. A semi-structured interview procedure is used to collect the data. The result of the analysis shows that teachers’ conceptual and operational understanding of SPS is weak. It affects the accuracy and appropriateness of the teacher’s selection of SPS assessment in chemistry learning.

Nuclear chemistry 1

International Nuclear Information System (INIS)

Macasek, F.

2009-01-01

This text-book (electronic book - multi-media CD-ROM) constitutes a course-book - author's collection of lectures. It consists of 9 lectures in which the reader acquaints with the basis of nuclear chemistry and radiochemistry: History of nucleus; Atomic nuclei; Radioactivity; Nuclear reactions and nucleogenesis; Isotopism; Ionizing radiation; Radiation measurement; Nuclear energetics; Isotopic indicators. This course-book may be interesting for students, post-graduate students of chemistry, biology, physics, medicine a s well as for teachers, scientific workers and physicians. (author)

The application analysis of high energy electron accelerator in food irradiation processing

International Nuclear Information System (INIS)

Deng Wenmin; Chen Hao; Feng Lei; Zhang Yaqun; Chen Xun; Li Wenjun; Xiang Chengfen; Pei Ying; Wang Zhidong

2012-01-01

Irradiation technology of high energy electron accelerator has been highly concerned in food processing industry with its fast development, especially in the field of food irradiation processing. In this paper, equipment and research situation of high energy electron accelerator were collected, meanwhile, the similarities and differences between high energy electron beam and 60 Co γ-rays were discussed. In order to provide more references of high energy electron beam irradiation, the usages of high energy electron in food irradiation processing was prospected. These information would promote the development of domestic food irradiation industry and give a useful message to irradiation enterprises and researchers. (authors)

Handbook on process and chemistry of nuclear fuel reprocessing version 2

International Nuclear Information System (INIS)

2008-10-01

Aqueous nuclear fuel reprocessing technology, based on PUREX technology, has wide applicability as the principal reprocessing technology of the first generation, and relating technologies, waste management for example, are highly developed, too. It is quite important to establish a database summarizing fundamental information about the process and the chemistry of aqueous reprocessing, because it contributes to establish and develop fuel reprocessing technology and nuclear fuel cycle treating high burn-up UO 2 fuel and spent MOX fuel, and to utilize aqueous reprocessing technology much widely. This handbook is the second edition of the first report, which summarizes the fundamental data on process and chemistry, which was collected and examined by 'Editing Committee of Handbook on Process and Chemistry of Nuclear Fuel Reprocessing' from FY 1993 until FY 2000. (author)

Gas phase ion chemistry

CERN Document Server

Bowers, Michael T

1979-01-01

Gas Phase Ion Chemistry, Volume 1 covers papers on the advances of gas phase ion chemistry. The book discusses the advances in flow tubes and the measurement of ion-molecule rate coefficients and product distributions; the ion chemistry of the earth's atmosphere; and the classical ion-molecule collision theory. The text also describes statistical methods in reaction dynamics; the state selection by photoion-photoelectron coincidence; and the effects of temperature and pressure in the kinetics of ion-molecule reactions. The energy distribution in the unimolecular decomposition of ions, as well

High Structure Active Learning Pedagogy for the Teaching of Organic Chemistry: Assessing the Impact on Academic Outcomes

Science.gov (United States)

Crimmins, Michael T.; Midkiff, Brooke

2017-01-01

Organic Chemistry is a required course for programs in chemistry, biology, and many health science careers. It has historically been considered a highly challenging course with significant failure rates. As with many science disciplines, the teaching of Organic Chemistry has traditionally focused on unstructured exposition-centered delivery of…

Report of the Subpanel on High Energy Physics Manpower of the High Energy Physics Advisory Panel

International Nuclear Information System (INIS)

1978-06-01

A report of a study by a Subpanel which was appointed by the High Energy Physics Advisory Panel (HEPAP) to examine the production in recent years of new researchers in high energy physics and the rate at which they have moved into short term and permanent positions in the field. The Subpanel made use of the 1973 and 1975 ERDA Census data, statistics collected by others, as well as a number of surveys conducted by the Subpanel itself. Even though many uncertainties and gaps exist in the available data, several important points are presented. (1) New Ph.D. production in high energy physics has decreased in recent years even more rapidly than in physics as a whole. (2) New Ph.D.'s in experimental and theoretical high energy physics have been produced for many years in roughly equal numbers in spite of the fact that employment in the field at all levels shows a ratio of experiment-to-theory approaching two-to-one. (3) A very large fraction of the approximately 1700 Ph.D.'s in high energy physics (employed at 78 universities and 5 national laboratories) hold tenured positions (383 theorists and 640 experimentalists). (4) The age distribution of those in the tenured ranks reveals that the number of retirements will be extremely small during the next decade but will then start to have a significant impact on the opportunities for those who are seeking careers in the field. (5) Promotions to tenure at the universities during the 4 year interval AY72/73-AY76/77 have averaged about 10 per year in experiment and 10 per year in theory

Water-chemistry data collected in and near Kaloko-Honokohau National Historical Park, Hawaii, 2012–2014

Science.gov (United States)

Tillman, Fred D.; Oki, Delwyn S.; Johnson, Adam G.

2014-01-01

Kaloko-Honokōhau National Historical Park (KAHO) on western Hawaiʻi was established in 1978 to preserve, interpret, and perpetuate traditional Native Hawaiian culture and activities, including the preservation of a variety of culturally and ecologically significant water resources that are vital to this mission. KAHO water bodies provide habitat for 1 threatened, 11 endangered, and 3 candidate threatened or endangered species. These habitats are sustained by, and in the case of ʻAimakapā Fishpond and the anchialine pools, entirely dependent on, groundwater from the Keauhou aquifer system. Development of inland impounded groundwater in the Keauhou aquifer system may affect the coastal freshwater-lens system on which KAHO depends, if the inland impounded-groundwater and coastal freshwater-lens systems are hydrologically connected. This report documents water-chemistry results from a U.S. Geological Survey study that collected and analyzed water samples from 2012 to 2014 from 25 sites in and near KAHO to investigate potential geochemical indicators in water that might indicate the presence or absence of a hydrologic connection between the inland impounded-groundwater and coastal freshwater-lens systems in the area. Samples were collected under high-tide and low-tide conditions for KAHO sites, and in dry-season and wet-season conditions for all sites. Samples were collected from two ocean sites, two fishponds, three anchialine pools, and three monitoring wells within KAHO. Two additional nearshore wells were sampled on property adjacent to and north of KAHO. Additional samples from the freshwater-lens system were collected from six inland wells located upslope from KAHO, including three production wells. Seven production wells in the inland impounded-groundwater system also were sampled. Water samples were analyzed for major ions, selected trace elements, rare-earth elements, strontium-isotope ratio, and stable isotopes of water. Precipitation samples from five

Flexible Aqueous Li-Ion Battery with High Energy and Power Densities.

Science.gov (United States)

Yang, Chongyin; Ji, Xiao; Fan, Xiulin; Gao, Tao; Suo, Liumin; Wang, Fei; Sun, Wei; Chen, Ji; Chen, Long; Han, Fudong; Miao, Ling; Xu, Kang; Gerasopoulos, Konstantinos; Wang, Chunsheng

2017-11-01

A flexible and wearable aqueous symmetrical lithium-ion battery is developed using a single LiVPO 4 F material as both cathode and anode in a "water-in-salt" gel polymer electrolyte. The symmetric lithium-ion chemistry exhibits high energy and power density and long cycle life, due to the formation of a robust solid electrolyte interphase consisting of Li 2 CO 3 -LiF, which enables fast Li-ion transport. Energy densities of 141 Wh kg -1 , power densities of 20 600 W kg -1 , and output voltage of 2.4 V can be delivered during >4000 cycles, which is far superior to reported aqueous energy storage devices at the same power level. Moreover, the full cell shows unprecedented tolerance to mechanical stress such as bending and cutting, where it not only does not catastrophically fail, as most nonaqueous cells would, but also maintains cell performance and continues to operate in ambient environment, a unique feature apparently derived from the high stability of the "water-in-salt" gel polymer electrolyte. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The radiation chemistry of macromolecules

CERN Document Server

1973-01-01

The Radiation Chemistry of Macromolecules, Volume II is a collection of papers that discusses radiation chemistry of specific systems. Part 1 deals with radiation chemistry of substituted vinyl polymers, particularly polypropylene (PP) as its structure is intermediate between polyethylene and polyisobutylene. This part also discusses polypropylene oxide (PPOx) for it can be prepared in the atactic, isotactic, and optically active forms. One paper focuses on the fundamental chemical processes and the changes in physical properties that give rise to many different applications of polystyrene. An

A case study of the effects of social experiences on the science identity formation of Mexican American females in high school chemistry

Science.gov (United States)

Beeton, Renee P.

Mexican Americans are a rapidly growing ethnic group in the United States. However, they are noticeably absent from physical science fields. Little research has explored the experiences of Mexican American girls in high school chemistry. The theories of identity based on communities of practice and multicultural feminism framed this year-long case study of nine Mexican American girls in a high school chemistry course. This study explored the social encounters and experiences that shaped the participants' identities and how their views of themselves affected their attitudes towards high school chemistry and future science careers. Data collection included a focus group and in-depth interviews with the participants, classroom observations, and teacher interviews. Five main identities influenced the participants' potential to become a scientist: ethnic, gender, science, student, and college. Mexican ethnic identity was the overarching identity; however gender also influenced the participants' other identities. The participants were aware of ethnic gender stereotypes that might hinder them from being successful in science. Also, ethnic factors, such as citizenship and abilities to receive financial aid limited their views of themselves as chemists. Participatory science, student, and school identities were all needed in order for the participants to be potential scientists. Family expectations, authentic relationships with teachers, and personal connections were important factors in the development of these participatory identities.

Radiation chemistry of water at low dose rates with emphasis on the energy balance

International Nuclear Information System (INIS)

Fletcher, J.W.

1982-09-01

There has been considerable interest in absorbed dose water calorimetry. In order to accurately relate the temperature change to the absorbed dose, the energy balance of the overall chemistry of the system must be known. The radiolytic products and their yields are affected by dose rate, dose and added solutes. The yields of the radiolytic products have been calculated using a computer program developed at Atomic Energy of Canada. The chemical energy balance was determined as a function of dose for various dose rates and initial concentrations of hydrogen (H 2 ), oxygen (O 2 ), and hydrogen peroxide (H 2 O 2 ). In solutions containing H 2 O 2 or O 2 and H 2 the chemical reactions were exothermic; in other cases they were endothermic. Approach to equilibrium and equilbrium conditions are discussed

Transactinide nuclear chemistry at JAERI

International Nuclear Information System (INIS)

Nagame, Y.; Haba, H.; Tsukada, K.

2002-01-01

Nuclear chemistry study of trans actinide elements in Japan is currently being in progress at JAERI (Japan Atomic Energy Research Institute). We have developed new experimental apparatuses: a beam-line safety system for the usage of the gas-jet coupled radioactive 248 Cm target chamber, a rotating wheel catcher apparatus for the measurement of α and spontaneous fission decay of the transactinides, MANON (Measurement system for Alpha particles and spontaneous fission events ON line), and an automated rapid chemical separation apparatus based on the high performance liquid chromatography, AIDA (Automated Ion exchange separation system coupled with the Detection apparatus for Alpha spectroscopy). The transactinide nuclei, 261 Rf and 262 Db, have been successfully produced via the reactions of 248 Cm( 18 O,5n) and 248 Cm( 19 F,5n), respectively, and the excitation functions for each reaction have been measured to evaluate the optimum irradiation condition for the production of these nuclei. The maximum cross sections in each reaction were 13 nb at the 18 O beam energy of 94-MeV and 1.5 Nb at the 103-MeV 19 F beam energy. On-line ion exchange experiments of Rf together with the lighter homologues Zr and Hf in the HCl, HNO 3 and HF solutions with AIDA have been carried out, and the results clearly show that the behavior of Rf is typical of the group-4 element. Relativistic molecular orbital calculations of the chloride and nitrate complexes of tetravalent Rf are also being performed to gain an understanding of the complex chemistry. Prospects and some recent experimental results for the nuclear chemistry study of the transactinide elements at JAERI are discussed. (author)

Excitation in the radiation chemistry of inorganic gases

International Nuclear Information System (INIS)

Willis, C.; Boyd, A.W.

1976-01-01

Gas phase radiation chemistry yield data and electron impact cross-section data are used to derive excitation mechanisms and to discuss the role of excited states in the radiation chemistry of O 2 , N 2 , N 2 O, CO, CO 2 , H 2 S, H 2 O and NH 3 . For each of these systems available cross-sections for ionization and neutral excitation are listed, together with relevant reaction rate data and a summary of the radiation chemistry studies at both high and low dose rates. In general, fairly complete mechanisms are derived and further tested by energy balance calculations. In order to present as complete a picture as possible, a summary of rates and products of ion-neutralization reactions is given at the end of the paper. (author)

Radiation chemistry of biologically compatible polymers

International Nuclear Information System (INIS)

Hill, D.J. T.; Pomery, P.J.; Saadat, G.; Whittaker, A.K.

1996-01-01

Full text: Poly (2-hydroxy ethyl methacrylate) [PHEMA] and poly (2-ethoxy ethyl methacrylate) [PEEMA] are of biomedical and industrial interest due to their biocompatibility with living tissue. In this paper the effect of high energy radiation on these polymers is reported. PHEMA and PEEMA have similar molecular structures to poly (methyl methacrylate)[PMMA], and the γ irradiation of this polymer is well understood. Hence the radiation chemistry of PMMA is used as model system for the the analysis of the radiation chemistry of these polymers. The mechanism of the radiation induced chemistry of the polymers has been investigated using a range of techniques including electron spin resonance spectroscopy (ESR) to establish free radical pathways, GC to identify small molecule volatile products, NMR to identify small molecule radiation products and Gel Permeation Chromatography (GPC) to determine molecular weight changes. Whilst much of the major part of the radiation chemistry can be attributed to similar reactions which can be observed in PMMA, there are a number of new radicals which are present as a result of the influence of the side chain interactions which reduces the mobility of the polymer chain

Low-energy physics of high-temperature superconductors

International Nuclear Information System (INIS)

Emery, V.J.; Kivelson, S.A.

1992-01-01

It is argued that the low-energy properties of high temperature superconductors are dominated by the interaction between the mobile holes and a particular class of collective modes, corresponding to local large-amplitude low-energy fluctuations in the hole density. The latter are a consequence of the competition between the effects of long-range Coulomb interactions and the tendency of a low concentration of holes in an antiferromagnet to phase separate. The low-energy behavior of the system is governed by the same fixed point as the two-channel Kondo problem, which accounts for the ''universality'' of the properties of the cuprate superconductors. Predictions of the optical properties and the spin dynamics are compared with experiment. The pairing resonance of the two Kondo problem gives a mechanism of high temperature superconductivity with an unconventional symmetry of the order parameter

Progress report 1987-1988. Reactor Chemistry Department

International Nuclear Information System (INIS)

1988-01-01

Review of the activities performed by the Reactor Chemistry Department of the National Atomic Energy Commission of Argentina during 1987-1988. This department provides services and assistance in all matters related to water chemistry and nuclear reactors chemistry, in all their phases: design, construction, commissioning and decommissioning. The appendix includes information on the Reactor Chemistry Department staff, its publications, services, seminars, courses and conferences performed during 1987-1988. (Author) [es

Solar system for exploitation of the whole collected energy

Science.gov (United States)

Ciamberlini, C.; Francini, F.; Longobardi, G.; Piattelli, M.; Sansoni, P.

2003-09-01

An innovative architecture for the exploitation of the whole collected solar energy is described. A sun pointing optical concentrator focuses the received energy, containing the part of the required solar spectrum, in a low loss optical fibre transmission line. The optical panel is small in size and able to follow the sun in order to collect the maximum of its energy. The support is flat, 5 mm thick and includes four optical concentrators. The efficiency of the optical system depends on the optical configuration and on the material utilised for the optical components. Single commercial connector to the fixed fibres connects the fibre optics' four free ends. The energy is therefore properly transported to any user's end with an easy installation. The system was experimented for lightening, during the day, dissipated in a dark load in order to produce heat in some equipment and for photovoltaic applications. The total efficiency of the system was between 68% and 72%. Once the solar energy reaches the end of the transmission line, it can be addressed to the required utilisation by means of an optical switch, which redirects the sunlight towards the desired applicator. This procedure allows utilising the 100% of the sun-collected energy. Since the size of the panel was small, it can be placed, on the roof, on the garden, on the window-sill, on the field and on all sides exposed to sunlight.

Systems chemistry: All in a spin

Science.gov (United States)

Clark, Lucy; Lightfoot, Philip

2016-05-01

A fundamental challenge in systems chemistry is to engineer the emergence of complex behaviour. The collective structures of metal cyanide chains have now been interpreted in the same manner as the myriad of magnetic phases displayed by frustrated spin systems, highlighting a symbiotic approach between systems chemistry and magnetism.

Sodium and cover gas chemistry in the high temperature sodium facility

International Nuclear Information System (INIS)

McCown, J.J.; Duncan, H.C.

1976-01-01

The equipment and procedures used in following sodium and cover gas chemistry changes in the High Temperature Sodium Facility are presented. The methods of analysis and results obtained are given. Impurity trends which have been measured during the facility operations are discussed

High-Energy-Density Metal-Oxygen Batteries: Lithium-Oxygen Batteries vs Sodium-Oxygen Batteries.

Science.gov (United States)

Song, Kyeongse; Agyeman, Daniel Adjei; Park, Mihui; Yang, Junghoon; Kang, Yong-Mook

2017-12-01

The development of next-generation energy-storage devices with high power, high energy density, and safety is critical for the success of large-scale energy-storage systems (ESSs), such as electric vehicles. Rechargeable sodium-oxygen (Na-O 2 ) batteries offer a new and promising opportunity for low-cost, high-energy-density, and relatively efficient electrochemical systems. Although the specific energy density of the Na-O 2 battery is lower than that of the lithium-oxygen (Li-O 2 ) battery, the abundance and low cost of sodium resources offer major advantages for its practical application in the near future. However, little has so far been reported regarding the cell chemistry, to explain the rate-limiting parameters and the corresponding low round-trip efficiency and cycle degradation. Consequently, an elucidation of the reaction mechanism is needed for both lithium-oxygen and sodium-oxygen cells. An in-depth understanding of the differences and similarities between Li-O 2 and Na-O 2 battery systems, in terms of thermodynamics and a structural viewpoint, will be meaningful to promote the development of advanced metal-oxygen batteries. State-of-the-art battery design principles for high-energy-density lithium-oxygen and sodium-oxygen batteries are thus reviewed in depth here. Major drawbacks, reaction mechanisms, and recent strategies to improve performance are also summarized. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Research needs and opportunities in radiation chemistry workshop

Energy Technology Data Exchange (ETDEWEB)

Barbara, Paul F

1998-04-19

There is a growing urgency for forefront basic research on ionizing radiation-induced chemical reactions, due to the relevance of these reactions in such areas of critical national need as environmental waste management, environmental remediation, nuclear energy production, and medical diagnosis and radiation therapy. Fortunately, the emergence of new theoretical and experimental tools for the study of radiation-induced chemical and physical processes, i.e. Radiation Chemistry, makes future progress quite promising. Nevertheless, a recent decline in he number of young investigators in radiation chemistry, as well as a natural obsolescence of large research facilities in radiation chemistry are serious obstacles to further progress. Understanding radiation-induced processes is of vital significance in such diverse fields as waste remediation in environmental cleanup, radiation processing of polymers and food, medical diagnosis and therapy, catalysis of chemical reactions, environmentally benign synthesis, and nuclear energy production. Radiation chemistry provides for these fields fundamental quantitative data, such as reaction rate coefficients, diffusion coefficients, radiation chemical yields, etc. As well as providing useful quantitative information of technological and medical importance, radiation chemistry is also a valuable tool for solving fundamental problems in chemistry and in material sciences. Exploiting the many facets of radiation chemistry requires a thorough and comprehensive understanding of the underlying chemical and physical processes. An understanding of the structure and dynamics of “tracks” produced by ionizing radiation is a central issue in the field. There is a continuing need to study the ultrafast processes that link the chemistry and physics of radiation-induced phenomena. This is especially true for practically important, but less well understood, nonstandard environments such as interfacial systems, supercritical media, and

Directory of energy data collection forms. Forms in use as of October 1995

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-01-01

This is an authoritative listing of selected public use forms currently used as basic energy information gathering tools by the Department of Energy (DOE). This directory provides an overview of DOE`s energy information collection programs for decisionmakers in Government and industry. Forms designed to collect energy information and used by the Energy Information Administration (EIA) as of October 1995 are included in this directory. For each form listed in this directory, an abstract is included that describes the form`s uses, its respondents, and the data collected. For the reader`s convenience in finding specific types of collections, several indices have been provided in this directory. A listing of the forms grouped by energy source and function begins on page 26. Beginning on page 38 are the publications derived from the collections, and on page 50, are the forms linked to general respondent categories.

Ionic Liquids as a Basis Context for Developing High school Chemistry Teaching Materials

Science.gov (United States)

Hernani; Mudzakir, A.; Sumarna, O.

2017-02-01

This research aims to produce a map of connectedness highschool chemical content with the context of the modern chemical materials applications based on ionic liquids. The research method is content analysis of journal articles related to the ionic liquid materials and the textbooks of high school chemistry and textbooks of general chemistry at the university. The instrument used is the development format of basic text that connect and combine content and context. The results showed the connectedness between: (1) the context lubricants ionic liquid with the content of ionic bonding, covalent bonding, metal bonding, interaction between the particles of matter, the elements of main group, the elements of transition group, and the classification of macromolecules; (2) the context of fuel cell electrolite with the content of ionic bonding, covalent bonding, metal bonding, interaction between the particles of matter, Volta cell, and electrolysis cell; (3) the contect of nanocellulose with the content of ionic bonding, covalent bonding, metal bonding, interaction between the particles of matter, colloid, carbon compound, and the classification of macromolecules; and (4) the context of artificial muscle system with the content of ionic bond, covalent bond, metal bonding, interaction between the particles of matter, hydrocarbons, electrolytes and non-electrolytes, and the classification of macromolecules. Based on the result of this content analysis, the context of ionic liquid is predicted can be utilized for the enrichment of high school chemistry and has the potential to become teaching material’s context of high school chemistry in the future.

High-School Chemistry Teaching through Environmentally Oriented Curricula

Science.gov (United States)

Mandler, Daphna; Mamlok-Naaman, Rachel; Blonder, Ron; Yayon, Malka; Hofstein, Avi

2012-01-01

Discussions held in the chemical education community have generated a variety of reports and recommendations for reforming the chemistry curriculum. The recommendations refer to teaching chemistry in the context of real-world issues. This has been suggested as a way to enhance students' motivation. It is suggested that real-world problems…

Influence of Aquifer Thermal Energy Storage (ATES) on groundwater chemistry: an overview of several cases in Belgium

Science.gov (United States)

Possemiers, Mathias; Huysmans, Marijke; Batelaan, Okke

2013-04-01

Environmental concerns and an increasing pressure on fossil fuels cause a rapidly growing interest in renewable energy. An interesting provider of such renewable energy is Aquifer Thermal Energy Storage (ATES), where groundwater in the aquifer is used as storage medium for summer heat and winter cold. The number of ATES systems has been continually increasing over the last years and will continue to increase in the future. Because ATES is often applied in aquifers also used for the production of drinking water, drinking water companies and environmental agencies are concerned about the impact of all these ATES systems on the groundwater quality in the long term. Because most ATES systems operate at relatively small temperature differences, ranging to several °C above and below the natural groundwater temperature, several studies show that the temperature influence on the groundwater quality is negligible. Mixing of the water column, on the other hand, possibly affects groundwater quality. The water is often extracted over a large portion of the aquifer in order to come to the desired flow rates. The composition of the groundwater on this interval may, however, differ from the top to the bottom by interaction with the surrounding aquifer material. The aim of this study is to evaluate the influence that Aquifer Thermal Energy Storage may have on the groundwater quality. Therefore the groundwater chemistry around seven ATES installations in the north of Belgium (Flanders) is evaluated. The selected ATES systems are located in several aquifers, which have major groundwater resources. The warm and cold wells of the different ATES installations were sampled and analyzed for the main chemical constituents during 4 to 7 years. The time series of the different chemical compounds are investigated per ATES well and compared with time series of several monitoring wells in the exploited aquifer. Results confirm that the temperatures occurring in the ATES systems do not affect

Introducing Relativity into Quantum Chemistry

Science.gov (United States)

Li, Wai-Kee; Blinder, S. M.

2011-01-01

It is not often realized by chemists that the special theory of relativity is behind several aspects of quantum chemistry. The Schrdinger equation itself is based on relations between space-time and energy-momentum four vectors. Electron spin is, of course, the most obvious manifestation of relativity. The chemistry of some heavy elements is…

First picosecond in radiation chemistry

International Nuclear Information System (INIS)

Bednar, J.

1983-01-01

The early processes of absorption by matter of ionizing radiation are discussed on the level of collision processes of electrons of the degradation spectrum of radiation with molecules of the medium. A short survey of the processes of initial excitations, superexcitations and ionizations is given occurring during absorption and relaxation processes. Collisions of fast charged particles with atoms and molecules are discussed within the first Bethe-Born approximation. A short theoretical description is given of the basic radiation chemical quantities, such as primary radiation chemical yield g and total absorbed energy Q/sub tot/ due to energy absorption from the totality of fast and slow electrons of the degradation spectrum. A short survey of current chemical and physical models of the track of a fast electron in condensed media is given together with some comments on the effect of the chemical composition of the medium on its initial radiation chemical decomposition. The model of the molecule in a high Rydberg state is sketched briefly together with some implications for radiation chemistry of formation and decay of this kind of highly excited matter. In conclusion, a survey of the initial yields of products in gases and track entities in liquids is presented and a few remarks are made concerning the intrinsic problems of radiation sciences, i.e. radiation physics, chemistry, dosimetry and biology

Progress report 1983-1984 Reactor Chemistry Department

International Nuclear Information System (INIS)

1985-11-01

Description of the activity developed by the Reactor Chemistry Department of the National Atomic Energy Commission during the period 1983-1984 in its four divisions: Chemical Control; Moderator and Refrigerant Chemistry; Radiation Chemistry and Nuclear Power Plant's Service. A list of the publications made by the personnel during this period is also included. (M.E.L.) [es

Ultrashort particle sources: innovating advances for chemistry and trans-disciplinary domains

International Nuclear Information System (INIS)

Malka, V.; Faure, J.; Glinec, Y.; Gauduel, Y.A.

2005-01-01

High-energy laser interaction with matter (gaseous and solid targets) provides electric fields going beyond the limit of one tera-volt per meter (1 TV = 10 12 V) and permit efficient acceleration of particles in the relativistic regime, typically with MeV energy. Exceptional properties of these new particle sources (shortness, charge, emittance) may conjecture trans-disciplinary researches such as physics' accelerators, pre-thermal reactivity in soft matter, radiobiology and radiotherapy, imaging. The challenge of high-energy femto-chemistry is broached in the framework of water, 'the life's solvent'. (authors)

Green chemistry by nano-catalysis

KAUST Repository

Polshettiwar, Vivek

2010-01-01

Nano-materials are important in many diverse areas, from basic research to various applications in electronics, biochemical sensors, catalysis and energy. They have emerged as sustainable alternatives to conventional materials, as robust high surface area heterogeneous catalysts and catalyst supports. The nano-sized particles increase the exposed surface area of the active component of the catalyst, thereby enhancing the contact between reactants and catalyst dramatically and mimicking the homogeneous catalysts. This review focuses on the use of nano-catalysis for green chemistry development including the strategy of using microwave heating with nano-catalysis in benign aqueous reaction media which offers an extraordinary synergistic effect with greater potential than these three components in isolation. To illustrate the proof-of-concept of this "green and sustainable" approach, representative examples are discussed in this article. © 2010 The Royal Society of Chemistry.

The Contribution of Constructivist Instruction Accompanied by Concept Mapping in Enhancing Pre-Service Chemistry Teachers' Conceptual Understanding of Chemistry in the Laboratory Course

Science.gov (United States)

Aydin, Sevgi; Aydemir, Nurdane; Boz, Yezdan; Cetin-Dindar, Ayla; Bektas, Oktay

2009-01-01

The present study aimed to evaluate whether a chemistry laboratory course called "Laboratory Experiments in Science Education" based on constructivist instruction accompanied with concept mapping enhanced pre-service chemistry teachers' conceptual understanding. Data were collected from five pre-service chemistry teachers at a university…

The Importance of Computer Based Active Learning for Basic Chemistry in Vocational High Schools

Directory of Open Access Journals (Sweden)

Tuğçe GÜNTER

2011-01-01

Full Text Available Chemistry is a very comprehensive discipline that researches atoms; molecules; the structure of matter in the form of element or compound; combinations, and physical and chemical properties of matter; macroscopic and microscopic transformations of matters; the energy and entropy released or absorbed in the course of these transformations; the structures and functions of carbohydrates, lipids, proteins, enzymes, vitamins and minerals in the body. This discipline includes numerous reactions at the macroscopic, microscopic and particulate levels, abstract concepts, three-dimensional structure of molecules, mathematics, and graphics. It is important for students to be trained as scientists to internalize -with meaningful learning - chemistry having much abstract concepts. Especially for students in associate degree programs in Vocational High Schools, taking this integrated course will provide them to be more creative in their future professional work; to cope with and overcome analytical problems; to be self-learners; to fill the gaps concerning chemical analysis originated from secondary education; and to gain critical thinking and self-evaluation skills regarding chemical problems. In the age of developing science and technology, “Computer-Based Active Learning Method” emerged with the introduction of multi-media into education and training. In this context, students will learn difficult and complex mathematical operations and graphics interpretations more meaningfully with computer-based simulations and analogies.

The Use of Online Modules and the Effect on Student Outcomes in a High School Chemistry Class

Science.gov (United States)

Lamb, Richard L.; Annetta, Len

2013-10-01

The purpose of the study was to review the efficacy of online chemistry simulations in a high school chemistry class and provide discussion of the factors that may affect student learning. The sample consisted of 351 high school students exposed to online simulations. Researchers administered a pretest, intermediate test and posttest to measure chemistry content knowledge acquired during the use of online chemistry laboratory simulations. The authors also analyzed student journal entries as an attitudinal measure of chemistry during the simulation experience. The four analyses conducted were Repeated Time Measures Analysis of Variance, a three-way Analysis of Variance, Logistic Regression and Multiple Analysis of Variance. Each of these analyses provides for a slightly different aspect of factors regarding student attitudes and outcomes. Results indicate that there is a statistically significant main effect across grouping type (experimental versus control, p = 0.042, α = 0.05). Analysis of student journal entries suggests that attitudinal factors may affect student outcomes concerning the use of online supplemental instruction. Implications for this study show that the use of online simulations promotes increased understanding of chemistry content through open-ended and interactive questioning.

BWR and PWR chemistry operating experience and perspectives

International Nuclear Information System (INIS)

Fruzzetti, K.; Garcia, S.; Lynch, N.; Reid, R.

2014-01-01

It is well recognized that proper control of water chemistry plays a critical role in ensuring the safe and reliable operation of Boiling Water Reactors (BWRs) and Pressurized Water Reactors (PWRs). State-of-the-art water chemistry programs reduce general and localized corrosion of reactor coolant system, steam cycle equipment, and fuel cladding materials; ensure continued integrity of cycle components; and reduce radiation fields. Once a particular nuclear plant component has been installed or plant system constructed, proper water chemistry provides a global tool to mitigate materials degradation problems, thereby reducing the need for costly repairs or replacements. Recognizing the importance of proper chemistry control and the value in understanding the relationship between chemistry guidance and actual operating experience, EPRI continues to collect, monitor, and evaluate operating data from BWRs and PWRs around the world. More than 900 cycles of valuable BWR and PWR operating chemistry data has been collected, including online, startup and shutdown chemistry data over more than 10 years (> 20 years for BWRs). This paper will provide an overview of current trends in BWR and PWR chemistry, focusing on plants in the U.S.. Important chemistry parameters will be highlighted and discussed in the context of the EPRI Water Chemistry Guidelines requirements (i.e., those parameters considered to be of key importance as related to the major goals identified in the EPRI Guidelines: materials integrity; fuel integrity; and minimizing plant radiation fields). Perspectives will be provided in light of recent industry initiatives and changes in the EPRI BWR and PWR Water Chemistry Guidelines. (author)

High Collection Nonimaging Optics

Science.gov (United States)

Winston, Roland

1989-07-01

Nonimaging optics departs from the methods of traditional optical design to develop instead techniques for maximizing the collecting power of concentrating elements and systems. Designs which exceed the concentration attainable with focusing techniques by factors of four or more and approach the theoretical limit are possible (ideal concentrators). The methodology for designing high collection nonirnaging systems is described.

The Doctorate in Chemistry. Carnegie Essays on the Doctorate: Chemistry.

Science.gov (United States)

Breslow, Ronald

The Carnegie Foundation commissioned a collection of essays as part of the Carnegie Initiative on the Doctorate (CID). Essays and essayists represent six disciplines that are part of the CID: chemistry, education, English, history, mathematics, and neuroscience. Intended to engender conversation about the conceptual foundation of doctoral…

Measurements of local chemistry and structure in Ni(O)-YSZ composites during reduction using energy-filtered environmental TEM

DEFF Research Database (Denmark)

Jeangros, Quentin; Hansen, Thomas Willum; Wagner, Jakob Birkedal

2014-01-01

Energy-filtered transmission electron microscopy images are acquired during the reduction of a NiO-YSZ composite in H-2 up to 600 degrees C. Temperature-resolved quantitative information about both chemistry and structure is extracted with nm spatial resolution from the data, paving the way...

Thermal solar energy. Collective domestic hot water installations

International Nuclear Information System (INIS)

Garnier, Cedric; Chauvet, Chrystele; Fourrier, Pascal

2016-01-01

This brochure, edited by ADEME, the French office for energy management and sustainable development, gives a basic outlook on the way to complete the installation of a collective domestic water solar heating system. After some recall of what is solar energy, the thermal solar technology and the energy savings it may induce, this document presents the main hydraulic configurations of a solar heating system with water storage, the dimensioning of a solar water heating system and its cost estimation, the installation and the commissioning of the system, the monitoring and maintenance operations

The Professional Development of High School Chemistry Coordinators

Science.gov (United States)

Hofstein, Avi; Carmeli, Miriam; Shore, Relly

2004-02-01

The implementation of new content and pedagogical standards in science education necessitates intensive, long-term professional development of science teachers. In this paper, we describe the rationale and structure of a comprehensive and intensive professional development program of school-based leaders, namely school chemistry coordinators. The year-long program was designed so that the chemistry teachers who enrolled in the program were able to develop in three interrelated aspects: content knowledge, pedagogical content knowledge, and leadership ability. Several strategies for the development of these aspects were adopted from Loucks-Horsley, Hewson, Love, & Stiles (1998). The evaluation of the program focused on the changes that participating teachers underwent regarding their personal beliefs and their functioning as school chemistry coordinators in their schools.

Computer code validation by high temperature chemistry

International Nuclear Information System (INIS)

Alexander, C.A.; Ogden, J.S.

1988-01-01

At least five of the computer codes utilized in analysis of severe fuel damage-type events are directly dependent upon or can be verified by high temperature chemistry. These codes are ORIGEN, CORSOR, CORCON, VICTORIA, and VANESA. With the exemption of CORCON and VANESA, it is necessary that verification experiments be performed on real irradiated fuel. For ORIGEN, the familiar knudsen effusion cell is the best choice and a small piece of known mass and known burn-up is selected and volatilized completely into the mass spectrometer. The mass spectrometer is used in the integral mode to integrate the entire signal from preselected radionuclides, and from this integrated signal the total mass of the respective nuclides can be determined. For CORSOR and VICTORIA, experiments with flowing high pressure hydrogen/steam must flow over the irradiated fuel and then enter the mass spectrometer. For these experiments, a high pressure-high temperature molecular beam inlet must be employed. Finally, in support of VANESA-CORCON, the very highest temperature and molten fuels must be contained and analyzed. Results from all types of experiments will be discussed and their applicability to present and future code development will also be covered

Enhancing first year chemistry student's participation in practical ...

African Journals Online (AJOL)

In this study, enhancing student's participation in practical analytical ... The data were collected from I year chemistry undergraduate students of class size 56 of ... learning practical Chemistry were mainly due to problems in preparing a flow ...

CMOS monolithic active pixel sensors for high energy physics

Energy Technology Data Exchange (ETDEWEB)

Snoeys, W., E-mail: walter.snoeys@cern.ch

2014-11-21

Monolithic pixel detectors integrating sensor matrix and readout in one piece of silicon are only now starting to make their way into high energy physics. Two major requirements are radiation tolerance and low power consumption. For the most extreme radiation levels, signal charge has to be collected by drift from a depletion layer onto a designated collection electrode without losing the signal charge elsewhere in the in-pixel circuit. Low power consumption requires an optimization of Q/C, the ratio of the collected signal charge over the input capacitance [1]. Some solutions to combine sufficient Q/C and collection by drift require exotic fabrication steps. More conventional solutions up to now require a simple in-pixel readout circuit. Both high voltage CMOS technologies and Monolithic Active Pixel Sensors (MAPS) technologies with high resistivity epitaxial layers offer high voltage diodes. The choice between the two is not fundamental but more a question of how much depletion can be reached and also of availability and cost. This paper tries to give an overview.

The evolution of high energy accelerators

International Nuclear Information System (INIS)

Courant, E.D.

1994-01-01

Accelerators have been devised and built for two reasons: In the first place, by physicists who needed high energy particles in order to have a means to explore the interactions between particles that probe the fundamental elementary forces of nature. And conversely, sometimes accelerator builders produce new machines for higher energy than ever before just because it can be done, and then challenge potential users to make new discoveries with the new means at hand. These two approaches or motivations have gone hand in hand. This lecture traces how high energy particle accelerators have grown from tools used for esoteric small-scale experiments to the gigantic projects of today. So far all the really high-energy machines built and planned in the world--except the SLC--have been ring accelerators and storage rings using the strong-focusing method. But this method has not removed the energy limit, it has only pushed it higher. It would seem unlikely that one can go beyond the Large Hadron Collider (LHC)--but in fact a workshop was held in Sicily in November 1991, concerned with the question of extrapolating to 100 TeV. Other acceleration and beam-forming methods are now being discussed--collective fields, laser acceleration, wake-field accelerators etc., all aimed primarily at making linear colliders possible and more attractive than with present radiofrequency methods. So far it is not entirely clear which of these schemes will dominate particle physics in the future--maybe something that has not been thought of as yet

Can radiation chemistry supply a highly efficient AO(R)P process for organics removal from drinking and waste water? A review.

Science.gov (United States)

Trojanowicz, Marek; Bojanowska-Czajka, Anna; Capodaglio, Andrea G

2017-09-01

The increasing role of chemistry in industrial production and its direct and indirect impacts in everyday life create the need for continuous search and efficiency improvement of new methods for decomposition/removal of different classes of waterborne anthropogenic pollutants. This review paper addresses a highly promising class of water treatment solutions, aimed at tackling the pressing problem of emerging contaminants in natural and drinking waters and wastewater discharges. Radiation processing, a technology originating from radiation chemistry studies, has shown encouraging results in the treatment of (mainly) organic water pollution. Radiation ("high energy") processing is an additive-free technology using short-lived reactive species formed by the radiolysis of water, both oxidative and reducing, to carry out decomposition of organic pollutants. The paper illustrates the basic principles of radiolytic treatment of organic pollutants in water and wastewaters and specifically of one of its most practical implementations (electron beam processing). Application examples, highlighting the technology's strong points and operational conditions are described, and a discussion on the possible future of this technology follows.

Kinetic energy in the collective quadrupole Hamiltonian from the experimental data

Energy Technology Data Exchange (ETDEWEB)

Jolos, R.V., E-mail: jolos@theor.jinr.ru [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Dubna State University, 141980 Dubna (Russian Federation); Kolganova, E.A. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Dubna State University, 141980 Dubna (Russian Federation)

2017-06-10

Dependence of the kinetic energy term of the collective nuclear Hamiltonian on collective momentum is considered. It is shown that the fourth order in collective momentum term of the collective quadrupole Hamiltonian generates a sizable effect on the excitation energies and the matrix elements of the quadrupole moment operator. It is demonstrated that the results of calculation are sensitive to the values of some matrix elements of the quadrupole moment. It stresses the importance for a concrete nucleus to have the experimental data for the reduced matrix elements of the quadrupole moment operator taken between all low lying states with the angular momenta not exceeding 4.

The High Energy Detector of Simbol-X

Science.gov (United States)

Meuris, A.; Limousin, O.; Lugiez, F.; Gevin, O.; Blondel, C.; Le Mer, I.; Pinsard, F.; Cara, C.; Goetschy, A.; Martignac, J.; Tauzin, G.; Hervé, S.; Laurent, P.; Chipaux, R.; Rio, Y.; Fontignie, J.; Horeau, B.; Authier, M.; Ferrando, P.

2009-05-01

The High Energy Detector (HED) is one of the three detection units on board the Simbol-X detector spacecraft. It is placed below the Low Energy Detector so as to collect focused photons in the energy range from 8 to 80 keV. It consists of a mosaic of 64 independent cameras, divided in 8 sectors. Each elementary detection unit, called Caliste, is the hybridization of a 256-pixel Cadmium Telluride (CdTe) detector with full custom front-end electronics into a unique component. The status of the HED design will be reported. The promising results obtained from the first micro-camera prototypes called Caliste 64 and Caliste 256 will be presented to illustrate the expected performance of the instrument.

The High Energy Detector of Simbol-X

International Nuclear Information System (INIS)

Meuris, A.; Limousin, O.; Blondel, C.; Le Mer, I.; Pinsard, F.; Cara, C.; Goetschy, A.; Martignac, J.; Laurent, P.; Chipaux, R.; Rio, Y.; Fontignie, J.; Horeau, B.; Ferrando, P.; Lugiez, F.; Gevin, O.; Tauzin, G.; Herve, S.; Authier, M.

2009-01-01

The High Energy Detector (HED) is one of the three detection units on board the Simbol-X detector spacecraft. It is placed below the Low Energy Detector so as to collect focused photons in the energy range from 8 to 80 keV. It consists of a mosaic of 64 independent cameras, divided in 8 sectors. Each elementary detection unit, called Caliste, is the hybridization of a 256-pixel Cadmium Telluride (CdTe) detector with full custom front-end electronics into a unique component. The status of the HED design will be reported. The promising results obtained from the first micro-camera prototypes called Caliste 64 and Caliste 256 will be presented to illustrate the expected performance of the instrument.

The effectiveness of process oriented guided inquiry learning to reduce alternate conceptions in secondary chemistry

Science.gov (United States)

Barthlow, Michelle J.

2011-12-01

A nonequivalent, control group, pretest-posttest design was used to investigate student achievement in secondary chemistry. This study investigated the effect of process oriented guided inquiry learning (POGIL) in high school chemistry to reduce alternate conceptions related to the particulate nature of matter versus traditional lecture pedagogy. Data were collected from chemistry students in four large high schools and analyzed using ANCOVA. The results show that POGIL pedagogy, as opposed to traditional lecture pedagogy, resulted in fewer alternate conceptions related to the particulate nature of matter. Male and female students in the POGIL group posted better posttest scores than their traditional group peers. African-American and Hispanic students in the POGIL group exhibited achievement gains consistent with Caucasian and Asian students. Further studies are needed to determine the value of POGIL to address achievement gap concerns in chemistry.

Chemistry of sustainable energy

CERN Document Server

Carpenter, Nancy E

2014-01-01

Energy BasicsWhat Is Energy?Energy, Technology, and SustainabilityEnergy Units, Terms, and AbbreviationsElectricity Generation and StorageOther ResourcesReferencesFossil FuelsFormation of Oil and GasExtraction of Fossil FuelsRefiningCarbon Capture and StorageSummaryOther ResourcesOnline Resources Related to Carbon Capture andSequestrationReferencesThermodynamicsIntroductionThe First Law of ThermodynamicsThe Second Law and Thermodynamic Cycles: the Carnot EfficiencyExerg

Stepwise Inquiry into Hard Water in a High School Chemistry Laboratory

Science.gov (United States)

Kakisako, Mami; Nishikawa, Kazuyuki; Nakano, Masayoshi; Harada, Kana S.; Tatsuoka, Tomoyuki; Koga, Nobuyoshi

2016-01-01

This study focuses on the design of a learning program to introduce complexometric titration as a method for determining water hardness in a high school chemistry laboratory. Students are introduced to the different properties and reactions of hard water in a stepwise manner so that they gain the necessary chemical knowledge and conceptual…

Advanced chemistry management system for nuclear power plants

International Nuclear Information System (INIS)

Maeda, Katsuji; Kobayashi, Yasuhiro; Nagasawa, Katsumi

2000-01-01

Chemistry control in a boiling water reactor (BWR) plant has a close relationship with radiation field buildup, fuel reliability, integrity of plant components and materials, performance of the water treatment systems and radioactive waste generation. Chemistry management in BWR plants has become more important in order to maintain and enhance plant reliability. Adequate chemistry control and management are also essential to establish, maintain, and enhance plant availability. For these reasons, we have developed the advanced chemistry management system for nuclear power plants in order to effectively collect and evaluate a large number of plant operating and chemistry data. (author)

Biodiesel and Integrated STEM: Vertical Alignment of High School Biology/Biochemistry and Chemistry

Science.gov (United States)

Burrows, Andrea C.; Breiner, Jonathan M.; Keiner, Jennifer; Behm, Chris

2014-01-01

This article explores the vertical alignment of two high school classes, biology and chemistry, around the core concept of biodiesel fuel production. High school teachers and university faculty members investigated biodiesel as it relates to societal impact through a National Science Foundation Research Experience for Teachers. Using an action…

Multivariate Statistical Analysis of Water Chemistry in Evaluating the Origin of Contamination in Many Devils Wash, Shiprock, New Mexico

International Nuclear Information System (INIS)

2012-01-01

This report evaluates the chemistry of seep water occurring in three desert drainages near Shiprock, New Mexico: Many Devils Wash, Salt Creek Wash, and Eagle Nest Arroyo. Through the use of geochemical plotting tools and multivariate statistical analysis techniques, analytical results of samples collected from the three drainages are compared with the groundwater chemistry at a former uranium mill in the Shiprock area (the Shiprock site), managed by the U.S. Department of Energy Office of Legacy Management. The objective of this study was to determine, based on the water chemistry of the samples, if statistically significant patterns or groupings are apparent between the sample populations and, if so, whether there are any reasonable explanations for those groupings.

Multivariate Statistical Analysis of Water Chemistry in Evaluating the Origin of Contamination in Many Devils Wash, Shiprock, New Mexico

Energy Technology Data Exchange (ETDEWEB)

None, None

2012-12-31

This report evaluates the chemistry of seep water occurring in three desert drainages near Shiprock, New Mexico: Many Devils Wash, Salt Creek Wash, and Eagle Nest Arroyo. Through the use of geochemical plotting tools and multivariate statistical analysis techniques, analytical results of samples collected from the three drainages are compared with the groundwater chemistry at a former uranium mill in the Shiprock area (the Shiprock site), managed by the U.S. Department of Energy Office of Legacy Management. The objective of this study was to determine, based on the water chemistry of the samples, if statistically significant patterns or groupings are apparent between the sample populations and, if so, whether there are any reasonable explanations for those groupings.

Chemistry and nuclear technology

International Nuclear Information System (INIS)

De Wet, W.J.

1977-01-01

The underlying principles of nuclear sciece and technology as based on the two basic phenomena, namely, radioactivity and nuclear reactions, with their relatively large associated energy changes, are outlined. The most important contributions by chemists in the overall historical development are mentioned and the strong position chemistry has attained in these fields is indicated. It is concluded that chemistry as well as many other scientific discplines (apart from general benefits) have largely benefitted from these nuclear developments [af

Development and Implementation of Inquiry-Based and Computerized-Based Laboratories: Reforming High School Chemistry in Israel

Science.gov (United States)

Barnea, Nitza; Dori, Yehudit Judy; Hofstein, Avi

2010-01-01

Reforms in science education in general and in chemistry education in particular have been introduced in many countries since the beginning of the 21st Century. Similarly, at this time in Israel both the content and pedagogy of the chemistry curriculum in high schools were reformed. New content and pedagogical standards emerged, fostering…

Designing an educative curriculum unit for teaching molecular geometry in high school chemistry

Science.gov (United States)

Makarious, Nader N.

Chemistry is a highly abstract discipline that is taught and learned with the aid of various models. Among the most challenging, yet a fundamental topic in general chemistry at the high school level, is molecular geometry. This study focused on developing exemplary educative curriculum materials pertaining to the topic of molecular geometry. The methodology used in this study consisted of several steps. First, a diverse set of models were analyzed to determine to what extent each model serves its purpose in teaching molecular geometry. Second, a number of high school teachers and college chemistry professors were asked to share their experiences on using models in teaching molecular geometry through an online questionnaire. Third, findings from the comparative analysis of models, teachers’ experiences, literature review on models and students’ misconceptions, the curriculum expectations of the Next Generation Science Standards and their emphasis on three-dimensional learning and nature of science (NOS) contributed to the development of the molecular geometry unit. Fourth, the developed unit was reviewed by fellow teachers and doctoral-level science education experts and was revised to further improve its coherence and clarity in support of teaching and learning of the molecular geometry concepts. The produced educative curriculum materials focus on the scientific practice of developing and using models as promoted in the Next Generations Science Standards (NGSS) while also addressing nature of science (NOS) goals. The educative features of the newly developed unit support teachers’ pedagogical knowledge (PK) and pedagogical content knowledge (PCK). The unit includes an overview, teacher’s guide, and eight detailed lesson plans with inquiry oriented modeling activities replete with models and suggestions for teachers, as well as formative and summative assessment tasks. The unit design process serves as a model for redesigning other instructional units in

Current status of high energy nucleon-meson transport code

Energy Technology Data Exchange (ETDEWEB)

Takada, Hiroshi; Sasa, Toshinobu [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1998-03-01

Current status of design code of accelerator (NMTC/JAERI code), outline of physical model and evaluation of accuracy of code were reported. To evaluate the nuclear performance of accelerator and strong spallation neutron origin, the nuclear reaction between high energy proton and target nuclide and behaviors of various produced particles are necessary. The nuclear design of spallation neutron system used a calculation code system connected the high energy nucleon{center_dot}meson transport code and the neutron{center_dot}photon transport code. NMTC/JAERI is described by the particle evaporation process under consideration of competition reaction of intranuclear cascade and fission process. Particle transport calculation was carried out for proton, neutron, {pi}- and {mu}-meson. To verify and improve accuracy of high energy nucleon-meson transport code, data of spallation and spallation neutron fragment by the integral experiment were collected. (S.Y.)

Lessons learned from a rigorous peer-review process for building the Climate Literacy and Energy Awareness (CLEAN) collection of high-quality digital teaching materials

Science.gov (United States)

Gold, A. U.; Ledley, T. S.; McCaffrey, M. S.; Buhr, S. M.; Manduca, C. A.; Niepold, F.; Fox, S.; Howell, C. D.; Lynds, S. E.

2010-12-01

The topic of climate change permeates all aspects of our society: the news, household debates, scientific conferences, etc. To provide students with accurate information about climate science and energy awareness, educators require scientifically and pedagogically robust teaching materials. To address this need, the NSF-funded Climate Literacy & Energy Awareness Network (CLEAN) Pathway has assembled a new peer-reviewed digital collection as part of the National Science Digital Library (NSDL) featuring teaching materials centered on climate and energy science for grades 6 through 16. The scope and framework of the collection is defined by the Essential Principles of Climate Science (CCSP 2009) and a set of energy awareness principles developed in the project. The collection provides trustworthy teaching materials on these socially relevant topics and prepares students to become responsible decision-makers. While a peer-review process is desirable for curriculum developer as well as collection builder to ensure quality, its implementation is non-trivial. We have designed a rigorous and transparent peer-review process for the CLEAN collection, and our experiences provide general guidelines that can be used to judge the quality of digital teaching materials across disciplines. Our multi-stage review process ensures that only resources with teaching goals relevant to developing climate literacy and energy awareness are considered. Each relevant resource is reviewed by two individuals to assess the i) scientific accuracy, ii) pedagogic effectiveness, and iii) usability/technical quality. A science review by an expert ensures the scientific quality and accuracy. Resources that pass all review steps are forwarded to a review panel of educators and scientists who make a final decision regarding inclusion of the materials in the CLEAN collection. Results from the first panel review show that about 20% (~100) of the resources that were initially considered for inclusion

Chemistry of Technetium

International Nuclear Information System (INIS)

Omori, Takashi

2001-01-01

Since the late 1970's the coordination chemistry of technetium has been developed remarkably. The background of the development is obviously related to the use of technetium radiopharmaceuticals for diagnosis in nuclear medicine. Much attention has also been denoted to the chemical behavior of environmental 99 Tc released from reprocessing plants. This review covers the several aspects of technetium chemistry, including production of radioisotopes, analytical chemistry and coordination chemistry. In the analytical chemistry, separation of technetium, emphasizing chromatography and solvent extraction, is described together with spectrophotometric determination of technetium. In the coordination chemistry of technetium, a characteristic feature of the chemistry of Tc(V) complexes is referred from the view point of the formation of a wide variety of highly stable complexes containing the Tc=O or Tc≡N bond. Kinetic studies of the preparation of Tc(III) complexes using hexakis (thiourea) technetium(III) ion as a starting material are summarized, together with the base hydrolysis reactions of Tc(III), Tc(IV) and Tc(V) complexes. (author)

Remote-controlling chemical reactions by light: towards chemistry with high spatio-temporal resolution.

Science.gov (United States)

Göstl, Robert; Senf, Antti; Hecht, Stefan

2014-03-21

The foundation of the chemical enterprise has always been the creation of new molecular entities, such as pharmaceuticals or polymeric materials. Over the past decades, this continuing effort of designing compounds with improved properties has been complemented by a strong effort to render their preparation (more) sustainable by implementing atom as well as energy economic strategies. Therefore, synthetic chemistry is typically concerned with making specific bonds and connections in a highly selective and efficient manner. However, to increase the degree of sophistication and expand the scope of our work, we argue that the modern aspiring chemist should in addition be concerned with attaining (better) control over when and where chemical bonds are being made or broken. For this purpose, photoswitchable molecular systems, which allow for external modulation of chemical reactions by light, are being developed and in this review we are covering the current state of the art of this exciting new field. These "remote-controlled synthetic tools" provide a remarkable opportunity to perform chemical transformations with high spatial and temporal resolution and should therefore allow regulating biological processes as well as material and device performance.

Radiation applications of physical chemistry

International Nuclear Information System (INIS)

Talrose, V.L.

1993-01-01

Many chemical energy problems have a physical chemistry nature connected with chemical kinetics and thermodynamics. In our country, the development in this field is associated with the name N.N. Semenov, who was involved in a large number of fundamental and applied physical chemistry problems.Energy development during the last decades created or sharpened new problems. Our new Institute, the Institute of Energy problems of Chemical Physics, USSR Academy of Sciences, is dealing with some of them. The present article is an overview of our work on radiation applications. Examples of the use of radiation in power industry (such as coal gasification), tire production, mechanical joints, metal powder production and sterilization of pharmaceutical products are given. Methods and problems involved in these applications are discussed and the great potential for vast utilization is demonstrated. (authors)

Nuclear chemistry progress report

International Nuclear Information System (INIS)

1984-09-01

The activities of the nuclear chemistry group at Indiana University during the period September 1, 1983 to August 31, 1984, are summarized. The primary thrust of our research program has continued to be the investigation of damped collision mechanisms at near-barrier energies and of linear momentum and energy transfer in the low-to-intermediate energy regime. In addition, during the past year we have initiated studies of complex fragment emission from highly excited nuclei and have also completed measurements relevant to understanding the origin and propagation of galactic cosmic rays. Equipment development efforts have resulted in significantly improving the resolution and solid-angle acceptance of our detector systems. The experimental program has been carried out at several accelerators including the Indiana University Cyclotron Facility, the Lawrence Berkeley Laboratory SuperHILAC, the Holifield Heavy-Ion Research Facility and the National Superconducting Cyclotron Laboratory at Michigan State University. Publications and activities are listed

Very high temperature chemistry: Science justification for containerless experimentation in space

Science.gov (United States)

Hofmeister, William H.; Nordine, Paul

1990-01-01

A summary is presented of the justification for application of containerless processing in space to high temperature science. Low earth orbit offers a gravitational environment that allows samples to be positioned in an experimental apparatus by very small forces. Well controlled experiments become possible on reactive materials at high temperatures in a reasonably quiescent state and without container contamination. This provides an opportunity to advance the science of high temperature chemistry that can only be realized with a commitment by NASA to provide advanced facilities for in-space containerless study of materials at very high temperature.

Reaction chemistry in rechargeable Li-O2 batteries.

Science.gov (United States)

Lim, Hee-Dae; Lee, Byungju; Bae, Youngjoon; Park, Hyeokjun; Ko, Youngmin; Kim, Haegyeom; Kim, Jinsoo; Kang, Kisuk

2017-05-22

The seemingly simple reaction of Li-O 2 batteries involving lithium and oxygen makes this chemistry attractive for high-energy-density storage systems; however, achieving this reaction in practical rechargeable Li-O 2 batteries has proven difficult. The reaction paths leading to the final Li 2 O 2 discharge products can be greatly affected by the operating conditions or environment, which often results in major side reactions. Recent research findings have begun to reveal how the reaction paths may be affected by the surrounding conditions and to uncover the factors contributing to the difficulty in achieving the reactions of lithium and oxygen. This progress report describes the current state of understanding of the electrode reaction mechanisms in Li-O 2 batteries; the factors that affect reaction pathways; and the effect of cell components such as solvents, salts, additives, and catalysts on the discharge product and its decomposition during charging. This comprehensive review of the recent progress in understanding the reaction chemistry of the Li-O 2 system will serve as guidelines for future research and aid in the development of reliable high-energy-density rechargeable Li-O 2 batteries.

Nanostructured energetic materials derived from sol-gel chemistry

International Nuclear Information System (INIS)

Simpson, R L; Tillotson, T M; Hrubesh, L W; Gash, A E

2000-01-01

Initiation and detonation properties are dramatically affected by an energetic material's microstructural properties. Sol-gel chemistry allows intimacy of mixing to be controlled and dramatically improved over existing methodologies. One material goal is to create very high power energetic materials which also have high energy densities. Using sol-gel chemistry we have made a nanostructured composite energetic material. Here a solid skeleton of fuel, based on resorcinol-formaldehyde, has nanocrystalline ammonium perchlorate, the oxidizer, trapped within its pores. At optimum stoichiometry it has approximately the energy density of HMX. Transmission electron microscopy indicated no ammonium perchlorate crystallites larger than 20 nm while near-edge soft x-ray absorption microscopy showed that nitrogen was uniformly distributed, at least on the scale of less than 80 nm. Small-angle neutron scattering studies were conducted on the material. Those results were consistent with historical ones for this class of nanostructured materials. The average skeletal primary particle size was on the order of 2.7 nm, while the nanocomposite showed the growth of small 1 nm size crystals of ammonium perchlorate with some clustering to form particles greater than 10 nm

Energetic M1 transitions as a probe of nuclear collectivity at high temperatures

International Nuclear Information System (INIS)

Baktash, C.

1987-01-01

At ORNL, we have recently utilized the Spin Spectrometer setup to investigate the differential effects of increasing spin and excitation energy on nuclear shape and collectivity in 158 Yb. Along the yrast line of this and other N = 88 nuclei, weakly prolate shapes gradually give way to triaxial, and then finally to non-collective oblate shapes as the spin approaches 40 h-bar. However, above the yrast line, large deformation and collectivity once again sets in. This is evidenced by the emergence of a broad quadrupole structure (E/sub γ/ ≅ 1.2 MeV) in the continuum gamma-ray spectra that grows with increasing temperature. The short (sub ps) lifetimes of these transitions attest to the collective nature of these structures. The emergence and growth of the quadrupole structure at high excitation energies is closely correlated with the appearance of energetic (E/sub γ/ ≅ 2.5 MeV), fast M1 transitions which form another broad structure in the continuum spectra. From the centroid of the M1 bump, a quadrupole deformation parameter of 0.35 is inferred. Because of this sensitivity, these energetic M1 transitions provide a unique probe of nuclear shape in the excitation energy range of ≅ 3 to 10 MeV. 6 refs., 2 figs

Balancing collective and individual interests in transactive energy management of interconnected micro-grid clusters

International Nuclear Information System (INIS)

Chen, Yang; Hu, Mengqi

2016-01-01

The emerging technology, transactive energy network, can allow multiple interconnected micro-grids (a.k.a. micro-grid clusters) to exchange energy for greater energy efficiency. Existing research has demonstrated that the micro-grid clusters can achieve some collective interests (e.g., minimizing total energy cost). However, some micro-grids may have to make sacrifices of their individual interests (e.g., increasing cost) for collective interests of the clusters. To bridge these research gaps, we propose four different transactive energy management models for micro-grid clusters where each micro-grid is allowed to have energy transactions with others. The first model focuses on maximizing collective interests, both the collective and individual interests are considered in the second model, and the last two models aim to maximize both the collective and individual interests. The performances of the proposed models are evaluated using a cluster of sixteen micro-grids with different energy profiles. It is demonstrated that 1) all of the four models can maximize the collective interests, 2) the third model can maximize the relative individual interests where each micro-grid can achieve the same percentage of cost savings as the clusters, and 3) the fourth model can maximize the absolute individual interests where each micro-grid can achieve the same amount of cost savings. - Highlights: • A modeling framework is developed for transactive energy management of the micro-grid clusters. • Four operation decision models are developed to balance the collective and individual interests. • The prices of local energy transaction are modeled. • The micro-grid clusters can achieve 15.34% energy cost savings.

Influence of centrifugation conditions on the results of 77 routine clinical chemistry analytes using standard vacuum blood collection tubes and the new BD-Barricor tubes.

Science.gov (United States)

Cadamuro, Janne; Mrazek, Cornelia; Leichtle, Alexander B; Kipman, Ulrike; Felder, Thomas K; Wiedemann, Helmut; Oberkofler, Hannes; Fiedler, Georg M; Haschke-Becher, Elisabeth

2018-02-15

Although centrifugation is performed in almost every blood sample, recommendations on duration and g-force are heterogeneous and mostly based on expert opinions. In order to unify this step in a fully automated laboratory, we aimed to evaluate different centrifugation settings and their influence on the results of routine clinical chemistry analytes. We collected blood from 41 healthy volunteers into BD Vacutainer PST II-heparin-gel- (LiHepGel), BD Vacutainer SST II-serum-, and BD Vacutainer Barricor heparin-tubes with a mechanical separator (LiHepBar). Tubes were centrifuged at 2000xg for 10 minutes and 3000xg for 7 and 5 minutes, respectively. Subsequently 60 and 21 clinical chemistry analytes were measured in plasma and serum samples, respectively, using a Roche COBAS instrument. High sensitive Troponin T, pregnancy-associated plasma protein A, ß human chorionic gonadotropin and rheumatoid factor had to be excluded from statistical evaluation as many of the respective results were below the measuring range. Except of free haemoglobin (fHb) measurements, no analyte result was altered by the use of shorter centrifugation times at higher g-forces. Comparing LiHepBar to LiHepGel tubes at different centrifugation setting, we found higher lactate-dehydrogenase (LD) (P = 0.003 to centrifuged at higher speed (3000xg) for a shorter amount of time (5 minutes) without alteration of the analytes tested in this study. When using LiHepBar tubes for blood collection, a separate LD reference value might be needed.

Why high energy physics

International Nuclear Information System (INIS)

Diddens, A.N.; Van de Walle, R.T.

1981-01-01

An argument is presented for high energy physics from the point of view of the practitioners. Three different angles are presented: The cultural consequence and scientific significance of practising high energy physics, the potential application of the results and the discovery of high energy physics, and the technical spin-offs from the techniques and methods used in high energy physics. (C.F.)

Correlative degree and collective side ward flow of final state particles in high energy heavy ion collisions

International Nuclear Information System (INIS)

Zhang Weigang

1999-01-01

A concept of correlative degree is proposed. Using the method of particle-group correlation's function, the effects of the particles with different correlative degrees on collective side ward flow are studied for 1.2A GeV Ar + Bal 2 collisions at the Bevalac stream chamber. The studies indicate that correlative degree is an important parameter on describing collective side ward flow properties. The minority of correlative particles (or fragments) with larger correlative degrees can produce the effect arising from the collective side ward flow, but the effect arising from high-order collective flow correlations can not be dominated by these minority of particles (or fragments). It is results from the collective contribution of the majority of collective particles (or fragments) with various correlative degrees

Ecology of subtropical, shallow water environments: chemistry of copper and chlorine introduced into marine systems during energy production

International Nuclear Information System (INIS)

1980-01-01

During the last three contract years, we have been involved in the study of the chemistry of the copper binding compounds occurring in coastal seawater. Initially our efforts were oriented towards the study of the complexing capacity of waters collected at various locations in the Miami, Florida area. Our study then shifted towards the concentration and the elucidation of these chelators

Creating a Context for Chemistry

Science.gov (United States)

Truman Schwartz, A.

Until relatively recently, the teaching of chemistry at the college and university level in the United States has been quite traditional and oriented primarily toward the preparation of chemists. Students not concentrating in the sciences have often been poorly served by existing courses. Chemistry in Context: Applying Chemistry to Society, a textbook for nonscience majors developed under the sponsorship of the American Chemical Society, is an effort to address the needs and interests of this audience. The book introduces the phenomena and principles of chemistry within the context of socially significant issues such as global warming, ozone depletion, alternate energy sources, nutrition, and genetic engineering. The chemistry is presented as needed to inform an understanding of the central topics, and the text features student-centered activities designed to promote critical thinking and risk-benefit analysis as well as an understanding of chemical principles. This paper summarizes the origin, development, content, pedagogy, evaluation, and influence of Chemistry in Context and considers its potential implications for other disciplines and the instruction of science majors.

Data Preservation in High Energy Physics

CERN Document Server

Mount, Richard; Le Diberder, Francois; Dubois-Felsmann, Gregory; Neal, Homer; Bellis, Matt; Boehnlein, Amber; Votava, Margaret; White, Vicky; Wolbers, Stephen; Konigsberg, Jacobo; Roser, Robert; Snider, Rick; Lucchesi, Donatella; Denisov, Dmitri; Soldner-Rembold, Stefan; Li, Qizhong; Varnes, Erich; Jonckheere, Alan; Gasthuber, Martin; Gülzow, Volker; Kemp, Yves; Ozerov, Dmitri; Diaconu, Cristinel; South, David; Lobodzinski, Bogdan; Olsson, Jan; Haas, Tobias; Wrona, Krzysztof; Szuba, Janusz; Schnell, Gunar; Sasaki, Takashi; Katayama, Nobu; Hernandez, Fabio; Mele, Salvatore; Holzner, Andre; Hemmer, Frederic; Schroeder, Matthias; Barring, Olof; Brun, Rene; Maggi, Marcello; Igo-Kemenes, Peter; Van Wezel, Jos; Heiss, Andreas; Chen, Gang; Wang, Yifang; Asner, David; Riley, Daniel; Corney, David; Gordon, John

2009-01-01

Data from high-energy physics (HEP) experiments are collected with significant financial and human effort and are mostly unique. At the same time, HEP has no coherent strategy for data preservation and re-use. An inter-experimental Study Group on HEP data preservation and long-term analysis was convened at the end of 2008 and held two workshops, at DESY (January 2009) and SLAC (May 2009). This document is an intermediate report to the International Committee for Future Accelerators (ICFA) of the reflections of this Study Group.

Light Collection in the High Energy X-ray Detector with the Pixelated CdWO4 Scintillator using Monte Carlo Method

Energy Technology Data Exchange (ETDEWEB)

Lim, Chang Hwy; Moon, Myung-Kook; Lee, Suhyun; Kim, Jongyul; Kim, Jeongho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Park, Jong Won [Korea Research Institute of Ships and Ocean Engineering, Daejeon (Korea, Republic of)

2015-05-15

The performance of indirect detectors, which use the scintillator as CdWO{sub 4}, BGO, CsI, NaI, etc., are effected by optical properties of scintillator and geometrical condition of scintillator. Some of generated lights by interaction between x-ray photons and scintillator are collected at the photo-sensor and others are absorbed in scintillator or escape out of detector. In order to make the high performance image detector, detector should be able to gather the generated lights as much as possible. To minimize the loss of generated lights, thickness of scintillator is to be chosen appropriately. Therefore, the quality of the image detector using the pixelated scintillator is determined by scintillator size, reflectance of scintillator surface, electric noise, etc. In this study, we carried out a study the correlation between the number of collected light and the change of thickness of scintillator using Monte Carlo method. As shown in results, the optimal thickness of a scintillator should be properly selected depending on the incident x-ray energy. In case of without reflector, the scintillator thickness range for x-ray detection is thinner than other cases (with reflector). In the case of a scintillator with reflector, number of collected light and the optima thickness of a scintillator is higher and thicker than scintillator without reflector.

American Chemical Society, Division of Environmental Chemistry

International Nuclear Information System (INIS)

Anon.

1991-01-01

Separate abstracts were prepared for 161 papers of this divisional meeting for the US Department of Energy's Database. Main topics discussed included: acid rain mitigation - liming technologies and environmental considerations; biotechnology for wastewater treatment; environmental chemistry of lakes and reservoirs and pollution prevention and process analytical chemistry

Very High Specific Energy, Medium Power Li/CFx Primary Battery for Launchers and Space Probes

Science.gov (United States)

Brochard, Paul; Godillot, Gerome; Peres, Jean Paul; Corbin, Julien; Espinosa, Amaya

2014-08-01

Benchmark with existing technologies shows the advantages of the lithium-fluorinated carbon (Li/CFx) technology for use aboard future launchers in terms of a low Total Cost of Ownership (TCO), especially for high energy demanding missions such as re-ignitable upper stages for long GTO+ missions and probes for deep space exploration.This paper presents the new results obtained on this chemistry in terms of electrical and climatic performances, abuse tests and life tests. Studies - co-financed between CNES and Saft - looked at a pure CFx version with a specific energy up to 500 Wh/kg along with a medium power of 80 to 100 W/kg.

Solar chemistry / hydrogen - Summary report on the research programme 2002; Forschungsprogramm Solarchemie / Wasserstoff

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

This summary report for the Swiss Federal Office of Energy (SFOE) on the solar chemistry / hydrogen research programme presents an overview of work done in these fields in Switzerland in 2002. It includes an overview of work done on 12 research and development projects and 9 pilot and demonstration projects. The volume is completed with a selection of 13 annual reports on particular topics, including transformation and storage of energy by photo-chemical, photo-electrochemical and photovoltaic means, generation of hydrogen using water splitting, solar production of zinc and calcium, catalytic synthesis, redox processes for the production of hydrogen and compressed air as a means of storing energy. Also covered are the topics of how solar chemistry can help reduce CO{sub 2} emissions and the management of the International Energy Agency's hydrogen annex 14. Further reports look at the destabilisation of metal hydride compounds, materials for sustainable energy technologies and diffusion barriers for high-pressure hydrogen tanks.

The 1991 Japan Solar Energy Society. Japan Wind Energy Association Joint Conference

Science.gov (United States)

1991-09-01

Thie paper summarizes the lectures presented at the research presentation conference held by the Japan Solar Energy Society and the Japan Wind Energy Association. The contents include a lecture relating to photovoltaic cells intended for efficiency improvement; a lecture relating to a light power generation system including the field test reports, improvements on peripheral devices and output characteristics; a lecture relating to optical chemistry; a lecture relating to heat pumps utilizing solar heat and well water; a lecture relating air conditioning utilizing photovoltaic cells; a lecture relating to heat systems utilizing solar heat directly; a lecture relating to heat collection; a lecture relating to cold heat for cooling using earth tubes; a lecture relating to direct utilization of ground water heat and solar heat; a lecture relating to underground heat storage; a lecture relating to accumulation of cold heat and hot heat; a lecture relating to insolation on the amount of insolation and spectroscopy; a lecture relating to light collection intended of energy saving; a lecture relating to improving materials including light collecting plates and thin films; a lecture relating to development and characteristics of solar cars; and a lecture relating to wind energy.

Mendeleev-2013. VII All-Russian conference of young scientists, postgraduate students and students with international participation on chemistry and nanomaterials. Book of abstracts. Section 4. Organic chemistry

International Nuclear Information System (INIS)

2013-01-01

VII All-Russian conference of young scientists, postgraduate students and students with international participation on chemistry and nanomaterials was conducted on the Chemistry department of Saint-Petersburg University on April, 2-5, 2013. In the conference participants from 14 countries took part. There were five sections: Nanochemistry and nanomaterials, Analytic chemistry, Inorganic chemistry, Organic chemistry, Physical chemistry. In the collection (Section 2 - Organic chemistry) there are the abstracts concerning different aspects of organic chemistry: synthesis and study of properties of heterocyclic, organometallic, biologically active, medicinal compounds, new ion exchange materials, reagents for analytic chemistry, etc [ru

Promoting sustainability through green chemistry

Energy Technology Data Exchange (ETDEWEB)

Kirchhoff, Mary M. [American Chemical Society, 1155 Sixteenth Street, NW, Washington, DC 20036 (United States)

2005-06-15

Green chemistry is an important tool in achieving sustainability. The implementation of green chemistry, the design of chemical products and processes that reduce or eliminate the use and generation of hazardous substances, is essential if the expanding global population is to enjoy an increased standard of living without having a negative impact on the health of the planet. Cleaner technologies will allow the chemical enterprise to provide society with the goods and services on which it depends in an environmentally responsible manner. Green chemistry provides solutions to such global challenges as climate change, sustainable agriculture, energy, toxics in the environment, and the depletion of natural resources. A collaborative effort by industry, academia, and government is needed to promote the adoption of the green chemistry technologies necessary to achieve a sustainable society.

Baseline prostatic specific antigen does not predict the outcome of high energy transurethral microwave thermotherapy

NARCIS (Netherlands)

Laguna, M. Pilar; Kiemeney, Lambertus A.; Debruyne, Frans M. J.; de La Rosette, Jean J. M. C. H.

2002-01-01

PURPOSE: We assessed the prognostic value of baseline prostate specific antigen (PSA) for outcome after high energy transurethral thermotherapy in patients with lower urinary tract symptoms. MATERIAL AND METHODS: Data were collected prospectively in 404 consecutive patients treated with high energy

Aspects of chemistry in management of radioactive liquid wastes from nuclear installations

International Nuclear Information System (INIS)

Yeotikar, R.G.

2007-01-01

Nuclear energy is the only source available to the mankind to fulfill the continuous and ever increasing demand of energy. The public acceptance and popularity of nuclear energy depends to a large extent on management of radioactive waste. The nuclear waste management demands eco-friendly process/systems. This article highlights the sources of different types of radioactive liquid wastes generated in the nuclear installation and their treatment process. The radioactive liquid waste is classified mainly into three categories based on activity levels e.g. low, intermediate and high level. The management of radioactive liquid waste is very critical because of its 'mobility and liquid' nature. Secondly the liquid wastes have wide range of activity and chemistry spectrum and their volumes are also different. Hence the methods for management of different types of liquid wastes are also different. Mostly the treatment and conditioning processes are chemical processes. The chemistry involved in the treatment and conditioning of these wastes, problems related with chemistry for each processes and efforts to solve these problems, aspects of adoption on plant scale, etc., have been discussed in this article. (author)

Solutions to selected exercise problems in quantum chemistry and spectroscopy

DEFF Research Database (Denmark)

Spanget-Larsen, Jens

2016-01-01

Suggested solutions to a number of problems from the collection "Exercise Problems in Quantum Chemistry and Spectroscopy", previously published on ResearchGate (DOI: 10.13140/RG.2.1.4024.8162).......Suggested solutions to a number of problems from the collection "Exercise Problems in Quantum Chemistry and Spectroscopy", previously published on ResearchGate (DOI: 10.13140/RG.2.1.4024.8162)....

Laboratory Activity Worksheet to Train High Order Thinking Skill of Student on Surface Chemistry Lecture

Science.gov (United States)

Yonata, B.; Nasrudin, H.

2018-01-01

A worksheet has to be a set with activity which is help students to arrange their own experiments. For this reason, this research is focused on how to train students’ higher order thinking skills in laboratory activity by developing laboratory activity worksheet on surface chemistry lecture. To ensure that the laboratory activity worksheet already contains aspects of the higher order thinking skill, it requires theoretical and empirical validation. From the data analysis results, it shows that the developed worksheet worth to use. The worksheet is worthy of theoretical and empirical feasibility. This conclusion is based on the findings: 1) Assessment from the validators about the theoretical feasibility aspects in the category is very feasible with an assessment range of 95.24% to 97.92%. 2) students’ higher thinking skill from N Gain values ranges from 0.50 (enough) to 1.00 (high) so it can be concluded that the laboratory activity worksheet on surface chemistry lecture is empirical in terms of worth. The empirical feasibility is supported by the responses of the students in very reasonable categories. It is expected that the laboratory activity worksheet on surface chemistry lecture can train students’ high order thinking skills for students who program surface chemistry lecture.

Recoil 18F-chemistry in fluoroalkanes

International Nuclear Information System (INIS)

Linde, K.D. van der.

1982-01-01

This thesis describes the study of the chemical reactions of recoil 18 F-atoms in gaseous fluoromethanes and fluoroethanes. A brief survey of the organic hot atom chemistry is given in Chapter I. Chapter II deals with the experimental procedures used in this investigation. The irradiation facilities, the vapour phase radio-chromatography and the identification, including the synthesis of some fluorocarbons, are described in detail. Chapter III consists of a study on the applicability of perfluoropropene, C 3 F 6 , as scavenger for thermal 18 F-atoms and radicals. Chapters IV, V, VI and VII deal with 18 F-recoil chemistry in gaseous fluoroethanes, using H 2 S as scavenger. Chapter VIII is a short discussion on the hot 18 F-atom based production of 18 F-labeled organic compounds via decay of the intermediate 18 Ne. A target system is proposed for production of this isotope in high energy and ultra high flux particle beams, which possibly would become available in fast breeders and fusion reactors. (Auth.)

Antiparallel Dynamic Covalent Chemistries.

Science.gov (United States)

Matysiak, Bartosz M; Nowak, Piotr; Cvrtila, Ivica; Pappas, Charalampos G; Liu, Bin; Komáromy, Dávid; Otto, Sijbren

2017-05-17

The ability to design reaction networks with high, but addressable complexity is a necessary prerequisite to make advanced functional chemical systems. Dynamic combinatorial chemistry has proven to be a useful tool in achieving complexity, however with some limitations in controlling it. Herein we introduce the concept of antiparallel chemistries, in which the same functional group can be channeled into one of two reversible chemistries depending on a controllable parameter. Such systems allow both for achieving complexity, by combinatorial chemistry, and addressing it, by switching from one chemistry to another by controlling an external parameter. In our design the two antiparallel chemistries are thiol-disulfide exchange and thio-Michael addition, sharing the thiol as the common building block. By means of oxidation and reduction the system can be reversibly switched from predominantly thio-Michael chemistry to predominantly disulfide chemistry, as well as to any intermediate state. Both chemistries operate in water, at room temperature, and at mildly basic pH, which makes them a suitable platform for further development of systems chemistry.

Development and Implementation of High School Chemistry Modules Using Touch-Screen Technologies

Science.gov (United States)

Lewis, Maurica S.; Zhao, Jinhui; Montclare, Jin Kim

2012-01-01

Technology was employed to motivate and captivate students while enriching their in-class education. An outreach program is described that involved college mentors introducing touch-screen technology into a high school chemistry classroom. Three modules were developed, with two of them specifically tailored to encourage comprehension of molecular…

Does Teaching Sequence Matter When Teaching High School Chemistry with Scientific Visualisations?

Science.gov (United States)

Fogarty, Ian; Geelan, David; Mukherjee, Michelle

2012-01-01

Five Canadian high school Chemistry classes in one school, taught by three different teachers, studied the concepts of dynamic chemical equilibria and Le Chatelier's Principle. Some students received traditional teacher-led explanations of the concept first and used an interactive scientific visualisation second, while others worked with the…

Energy-Neutral Data Collection Rate Control for IoT Animal Behavior Monitors

Directory of Open Access Journals (Sweden)

Jay Wilhelm

2017-11-01

Full Text Available Energy-neutral operation (ENO is a major concern for Internet of things (IoT sensor systems. Animals can be tagged with IoT sensors to monitor their movement and behavior. These sensors wirelessly upload collected data and can receive parameters to change their operation. Typically, the behavior monitors are powered by a battery where the system relies upon harvesting solar radiation for sustainable operation. Solar panels typically are used as the harvesting mechanism and can have a level of uncertainty regarding consistent energy delivery due to factors such as adverse weather, foliage, time of day, and individual animal behavior. The variability of available energy inevitably creates a trade-off in the rate at which data can be collected with respect to incoming and stored energy. The objective of this research was to investigate and simulate methods and parameters that can control the data collection rate of an IoT behavior monitor to achieve sustained operation with unknown and random energy harvesting. Analysis and development of a control system were performed by creating a software model of energy consumption and then simulating using different initial conditions and random energy harvesting rates for evaluation. The contribution of this effort was the exploration into the usage of a discrete-time gain scheduled Proportional–Integral–Derivative (PID that was tuned to a specific device configuration, using battery state of charge as an input, and found to maintain a battery level set-point, reject small solar harvesting energy disturbances, and maintain a consistent data collection rate throughout the day.

Optimisation of logistics processes of energy grass collection

Science.gov (United States)

Bányai, Tamás.

2010-05-01

The collection of energy grass is a logistics-intensive process [1]. The optimal design and control of transportation and collection subprocesses is a critical point of the supply chain. To avoid irresponsible decisions by right of experience and intuition, the optimisation and analysis of collection processes based on mathematical models and methods is the scientific suggestible way. Within the frame of this work, the author focuses on the optimisation possibilities of the collection processes, especially from the point of view transportation and related warehousing operations. However the developed optimisation methods in the literature [2] take into account the harvesting processes, county-specific yields, transportation distances, erosion constraints, machinery specifications, and other key variables, but the possibility of more collection points and the multi-level collection were not taken into consideration. The possible areas of using energy grass is very wide (energetically use, biogas and bio alcohol production, paper and textile industry, industrial fibre material, foddering purposes, biological soil protection [3], etc.), so not only a single level but also a multi-level collection system with more collection and production facilities has to be taken into consideration. The input parameters of the optimisation problem are the followings: total amount of energy grass to be harvested in each region; specific facility costs of collection, warehousing and production units; specific costs of transportation resources; pre-scheduling of harvesting process; specific transportation and warehousing costs; pre-scheduling of processing of energy grass at each facility (exclusive warehousing). The model take into consideration the following assumptions: (1) cooperative relation among processing and production facilties, (2) capacity constraints are not ignored, (3) the cost function of transportation is non-linear, (4) the drivers conditions are ignored. The

Dynamic combinatorial chemistry to identify binders of ThiT, an S-component of the energy-coupling factor transporter for thiamine

NARCIS (Netherlands)

Monjas, Leticia; Swier, Lotteke J Y M; Setyawati, Inda; Slotboom, Dirk Jan; Hirsch, Anna Katharina Herta

2017-01-01

We applied dynamic combinatorial chemistry (DCC) to identify ligands of ThiT, the S-component of the energy-coupling factor (ECF) transporter for thiamine in Lactococcus lactis. We used a pre-equilibrated dynamic combinatorial library (DCL) and saturation-transfer difference (STD) NMR spectroscopy

Metal-air batteries with high energy density: Li-air versus Zn-air

Energy Technology Data Exchange (ETDEWEB)

Lee, Jang-Soo; Sun, Tai Kim; Cao, Ruiguo; Choi, Nam-Soon; Lee, Kyu Tae; Cho, Jaephil [Interdisciplinary School of Green Energy, Ulsan National Institute of Science and Technology (UNIST), Ulsan (Korea, Republic of); Liu, Meilin [School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA (United States)

2011-01-01

In the past decade, there have been exciting developments in the field of lithium ion batteries as energy storage devices, resulting in the application of lithium ion batteries in areas ranging from small portable electric devices to large power systems such as hybrid electric vehicles. However, the maximum energy density of current lithium ion batteries having topatactic chemistry is not sufficient to meet the demands of new markets in such areas as electric vehicles. Therefore, new electrochemical systems with higher energy densities are being sought, and metal-air batteries with conversion chemistry are considered a promising candidate. More recently, promising electrochemical performance has driven much research interest in Li-air and Zn-air batteries. This review provides an overview of the fundamentals and recent progress in the area of Li-air and Zn-air batteries, with the aim of providing a better understanding of the new electrochemical systems. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Fluorescence resonance energy transfer (FRET) in chemistry and ...

Indian Academy of Sciences (India)

Förster distance dependence of the FRET rate. SANGEETA SAINI,1 HARJINDER SINGH2 and BIMAN BAGCHI1,*. 1Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012. 2Permanent address: Department of ...

Reflections on Doctoral Education in Chemistry. Carnegie Essays on the Doctorate: Chemistry.

Science.gov (United States)

Kwiram, Alvin L.

The Carnegie Foundation commissioned a collection of essays as part of the Carnegie Initiative on the Doctorate (CID). Essays and essayists represent six disciplines that are part of the CID: chemistry, education, English, history, mathematics, and neuroscience. Intended to engender conversation about the conceptual foundation of doctoral…

Environmental chemistry of the actinide elements

International Nuclear Information System (INIS)

Rao Linfeng

1986-01-01

The environmental chemistry of the actinide elements is a new branch of science developing with the application of nuclear energy on a larger and larger scale. Various aspects of the environmental chemistry of the actinide elements are briefly reviewed in this paper, such as its significance in the nuclear waste disposal, its coverage of research fields and possible directions for future study

Big Data Meets Quantum Chemistry Approximations: The Δ-Machine Learning Approach.

Science.gov (United States)

Ramakrishnan, Raghunathan; Dral, Pavlo O; Rupp, Matthias; von Lilienfeld, O Anatole

2015-05-12

Chemically accurate and comprehensive studies of the virtual space of all possible molecules are severely limited by the computational cost of quantum chemistry. We introduce a composite strategy that adds machine learning corrections to computationally inexpensive approximate legacy quantum methods. After training, highly accurate predictions of enthalpies, free energies, entropies, and electron correlation energies are possible, for significantly larger molecular sets than used for training. For thermochemical properties of up to 16k isomers of C7H10O2 we present numerical evidence that chemical accuracy can be reached. We also predict electron correlation energy in post Hartree-Fock methods, at the computational cost of Hartree-Fock, and we establish a qualitative relationship between molecular entropy and electron correlation. The transferability of our approach is demonstrated, using semiempirical quantum chemistry and machine learning models trained on 1 and 10% of 134k organic molecules, to reproduce enthalpies of all remaining molecules at density functional theory level of accuracy.

Australian Chemistry Test Item Bank: Years 11 & 12. Volume 1.

Science.gov (United States)

Commons, C., Ed.; Martin, P., Ed.

Volume 1 of the Australian Chemistry Test Item Bank, consisting of two volumes, contains nearly 2000 multiple-choice items related to the chemistry taught in Year 11 and Year 12 courses in Australia. Items which were written during 1979 and 1980 were initially published in the "ACER Chemistry Test Item Collection" and in the "ACER…

Exploring Different Types of Assessment Items to Measure Linguistically Diverse Students' Understanding of Energy and Matter in Chemistry

Science.gov (United States)

Ryoo, Kihyun; Toutkoushian, Emily; Bedell, Kristin

2018-01-01

Energy and matter are fundamental, yet challenging concepts in middle school chemistry due to their abstract, unobservable nature. Although it is important for science teachers to elicit a range of students' ideas to design and revise their instruction, capturing such varied ideas using traditional assessments consisting of multiple-choice items…

Radical Rearrangement Chemistry in Ultraviolet Photodissociation of Iodotyrosine Systems: Insights from Metastable Dissociation, Infrared Ion Spectroscopy, and Reaction Pathway Calculations.

Science.gov (United States)

Ranka, Karnamohit; Zhao, Ning; Yu, Long; Stanton, John F; Polfer, Nicolas C

2018-05-29

We report on the ultraviolet photodissociation (UVPD) chemistry of protonated tyrosine, iodotyrosine, and diiodotyrosine. Distonic loss of the iodine creates a high-energy radical at the aromatic ring that engages in hydrogen/proton rearrangement chemistry. Based on UVPD kinetics measurements, the appearance of this radical is coincident with the UV irradiation pulse (8 ns). Conversely, sequential UVPD product ions exhibit metastable decay on ca. 100 ns timescales. Infrared ion spectroscopy is capable of confirming putative structures of the rearrangement products as proton transfers from the imine and β-carbon hydrogens. Potential energy surfaces for the various reaction pathways indicate that the rearrangement chemistry is highly complex, compatible with a cascade of rearrangements, and that there is no preferred rearrangement pathway even in small molecular systems like these. Graphical Abstract.

Chemistry and radioactivity: a century after Marie Curie

International Nuclear Information System (INIS)

Guillaumont, R.

2011-01-01

Coupling chemistry and radioactivity has led to radiochemistry, the part of chemistry dealing with the behaviour of radioactive materials. Many activities are of concern, as well in basic research as in the fields of health and energy. They call researches going from the study of the extremely diluted radioactive material (environment) until that of the most man-made radioactive material ever produced (spent nuclear fuel from reactors). When radiochemistry is not the mirror of the traditional chemistry, it uses in radioactive surroundings its own methods based on the measurement of the emitted rays. Radiochemistry will have in the next decades a major input to prepare the nuclear energy of the future. (author)

Final Report: Main Group Element Chemistry in Service of Hydrogen Storage and Activation

Energy Technology Data Exchange (ETDEWEB)

David A. Dixon; Anthony J. Arduengo, III

2010-09-30

Replacing combustion of carbon-based fuels with alternative energy sources that have minimal environmental impact is one of the grand scientific and technological challenges of the early 21st century. Not only is it critical to capture energy from new, renewable sources, it is also necessary to store the captured energy efficiently and effectively for use at the point of service when and where it is needed, which may not be collocated with the collection site. There are many potential storage media but we focus on the storage of energy in chemical bonds. It is more efficient to store energy on a per weight basis in chemical bonds. This is because it is hard to pack electrons into small volumes with low weight without the use of chemical bonds. The focus of the project was the development of new chemistries to enable DOE to meet its technical objectives for hydrogen storage using chemical hydrogen storage systems. We provided computational chemistry support in terms of thermodynamics, kinetics, and properties prediction in support of the experimental efforts of the DOE Center of Excellence for Chemical Hydrogen Storage. The goal of the Center is to store energy in chemical bonds involving hydrogen atoms. Once the hydrogen is stored in a set of X-H/Y-H bonds, the hydrogen has to be easily released and the depleted fuel regenerated very efficiently. This differs substantially from our current use of fossil fuel energy sources where the reactant is converted to energy plus CO2 (coal) or CO2 and H2O (gasoline, natural gas), which are released into the atmosphere. In future energy storage scenarios, the spent fuel will be captured and the energy storage medium regenerated. This places substantial additional constraints on the chemistry. The goal of the computational chemistry work was to reduce the time to design new materials and develop materials that meet the 2010 and 2015 DOE objectives in terms of weight percent, volume, release time, and regeneration ability. This

Main Group Element Chemistry in Service of Hydrogen Storage and Activation. Final report

International Nuclear Information System (INIS)

Dixon, David A.; Arduengo, Anthony J. III

2010-01-01

Replacing combustion of carbon-based fuels with alternative energy sources that have minimal environmental impact is one of the grand scientific and technological challenges of the early 21st century. Not only is it critical to capture energy from new, renewable sources, it is also necessary to store the captured energy efficiently and effectively for use at the point of service when and where it is needed, which may not be collocated with the collection site. There are many potential storage media but we focus on the storage of energy in chemical bonds. It is more efficient to store energy on a per weight basis in chemical bonds. This is because it is hard to pack electrons into small volumes with low weight without the use of chemical bonds. The focus of the project was the development of new chemistries to enable DOE to meet its technical objectives for hydrogen storage using chemical hydrogen storage systems. We provided computational chemistry support in terms of thermodynamics, kinetics, and properties prediction in support of the experimental efforts of the DOE Center of Excellence for Chemical Hydrogen Storage. The goal of the Center is to store energy in chemical bonds involving hydrogen atoms. Once the hydrogen is stored in a set of X-H/Y-H bonds, the hydrogen has to be easily released and the depleted fuel regenerated very efficiently. This differs substantially from our current use of fossil fuel energy sources where the reactant is converted to energy plus CO 2 (coal) or CO 2 and H 2 O (gasoline, natural gas), which are released into the atmosphere. In future energy storage scenarios, the spent fuel will be captured and the energy storage medium regenerated. This places substantial additional constraints on the chemistry. The goal of the computational chemistry work was to reduce the time to design new materials and develop materials that meet the 2010 and 2015 DOE objectives in terms of weight percent, volume, release time, and regeneration ability

Detection systems for high energy particle producing gaseous ionization

International Nuclear Information System (INIS)

Duran, I.; Martinez, L.

1985-01-01

This report contains a review on the most used detectors based on the collection of the ionization produced by high energy particles: proportional counters, multiwire proportional chambers, Geiger-Mueller counters and drift chambers. In six sections, the fundamental principles, the field configuration and useful gas mixtures are discussed, most relevant devices are reported. (author)

Oxygen chemistry in biology: Vibrational spectroscopy, stable isotopes, and future applications

Energy Technology Data Exchange (ETDEWEB)

Babcock, G.T. [Michigan State Univ., East Lansing, MI (United States)

1994-12-01

Dioxygen is an ideally suited substrate for enzymatic manipulation in oxidation-reduction chemistry and in substrate transformation. It is a powerful oxidant with a midpoint potential of 0.815 at neutral pH; at the same time, however, it exists in a triplet state in its most stable electronic configuration. This latter property confers kinetic inertness as a result of spin-conservation restrictions on reaction chemistry. If these restrictions can be overcome and controlled, dioxygen`s high redox potential can be used to maximize efficiency in free-energy conversion processes and to effect activation of relatively inert substrates.

Species‐ and habitat‐specific otolith chemistry patterns inform riverine fisheries management

Science.gov (United States)

Radigan, William; Carlson, Andrew K.; Kientz, Jeremy; Chipps, Steven R.; Fincel, Mark J.; Graeb, Brian D. S.

2018-01-01

Geology and hydrology are drivers of water chemistry and thus important considerations for fish otolith chemistry research. However, other factors such as species and habitat identity may have predictive ability, enabling selection of appropriate elemental signatures prior to costly, perhaps unnecessary water/age‐0 fish sampling. The goal of this study was to develop a predictive methodology for using species and habitat identity to design efficient otolith chemistry studies. Duplicate water samples and age‐0 fish were collected from 61 sites in 4 Missouri River reservoirs for walleye Sander vitreus and one impoundment (Lake Sharpe, South Dakota) for other fishes (bluegill Lepomis macrochirus, black crappie Pomoxis nigromaculatus, gizzard shad Dorosoma cepedianum, largemouth bass Micropterus salmoides, smallmouth bass M. dolomieu, white bass Morone chrysops, white crappie P. annularis, and yellow perch Perca flavescens). Water chemistry (barium:calcium [Ba:Ca], strontium:calcium [Sr:Ca]) was temporally stable, spatially variable, and highly correlated with otolith chemistry for all species except yellow perch. Classification accuracies based on bivariate Ba:Ca and Sr:Ca signatures were high (84% across species) yet varied between floodplain and main‐channel habitats in a species‐specific manner. Thus, to maximize the reliability of otolith chemistry, researchers can use species classifications presented herein to inform habitat selection (e.g., study reservoir‐oriented species such as white bass in main‐channel environments) and habitat‐based classifications to inform species selection (e.g., focus floodplain studies on littoral species such as largemouth bass). Overall, species and habitat identity are important considerations for efficient, effective otolith chemistry studies that inform and advance fisheries and aquatic resource management.

New ideas for the design of optical devices with applications in solar energy collection

Energy Technology Data Exchange (ETDEWEB)

Chaves, Julio; Pereira, Manuel Collares

2001-07-01

New ideas for the design of optical devices and some applications to solar energy collection are presented. These are mainly solar concentrators resulting from the combination of known anidoloc (nonimaging) optics devices and known curves such as parabolic, elliptical, hyperbolic, circular arcs or flat mirrors. Other tailored curves are also used in some cases. Two possible applications are in compact high concentration devices for solar energy and ideal concentrators having a gap between the optics and the receiver. Only two dimensional solutions are explored in these cases. Due to the high number of internal reflections, the use of high reflectivity mirrors is mandatory or, alternatively, the use of total internal reflection. Combinations of 3D CPCs and torus are also presented. The obtained devices allow tracking of the sun without the need to move the receiver. An application to solar cooking is presented.

Annual Report (No. 2) of Center for Advanced Research of Energy Technology, Hokkaido University; Hokkaido Daigaku energy sentan kogaku kenkyu center nenpo dai 2 go

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-03-01

Compiled into this report are the activities and achievements of the center in fiscal 1995. Under study in the field of carbonaceous resources conversion reaction are the high-molecular coagulation structure, pyrolysis and carbonization, ignition, complex conversion of resources together with other resources, etc. Under study in the field of carbonaceous resources assessment are catalytic chemistry, organic chemistry, physical chemistry, and analytical chemistry. Under study in the field of the control of energy conversion are the generation of high-temperature thermal energy and its conversion into electromagnetic energy. In the study of ultimate materials engineering, materials are studied for use under hostile conditions such as in a nuclear fusion reactor. As for papers published in fiscal 1995, there are 9 in the field of carbonaceous resources conversion reaction, 11 in the field of carbonaceous resources assessment, 7 in the field of energy conversion control, 10 in the field of ultimate materials engineering, and 4 in other fields. Published also are 9 articles covering general remarks, interpretations, and reviews. As for academic lectures, 13 are given in the field of carbonaceous resources conversion reaction, 14 in the field of carbonaceous resources assessment, 27 in the field of energy conversion control, and 39 in the field of ultimate materials engineering. (NEDO)

Annual Report (No. 3) of Center for Advanced Research of Energy Technology, Hokkaido University; Hokkaido Daigaku energy sentan kogaku kenkyu center nenpo dai 3 go

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

Compiled into this report are the activities and achievements of the center in fiscal 1996. Its studies in the field of carbonaceous resources conversion reaction involve the high-molecular coagulation structure, pyrolysis and carbonization, ignition, complex conversion of resources together with other resources, etc.Under study in the field of carbonaceous resources evaluation are catalytic chemistry, organic chemistry, physical chemistry, and analytical chemistry. Under study in the field of the control of energy conversion are the generation of high-temperature thermal energy and its conversion into electromagnetic energy. In the study of ultimate materials engineering, materials are studied for use under hostile conditions such as in a nuclear fusion reactor, atomic reactor, and combustion plasma. As for papers published in fiscal 1996, there are 19 in the field of carbonaceous resources conversion reaction, 17 in the field of carbonaceous resources assessment, 6 in the field of energy conversion control, and 26 in the field of ultimate materials engineering. Published also are 8 articles covering general remarks, interpretations, and reviews. As for academic lectures, 31 are given in the field of carbonaceous resources conversion reaction, 20 in the field of carbonaceous resources assessment, 30 in the field of energy conversion control, and 38 in the field of ultimate materials engineering. (NEDO)

Annual Report (No. 4) of Center for Advanced Research of Energy Technology, Hokkaido University; Hokkaido Daigaku energy sentan kogaku kenkyu center nenpo dai 4 go

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-03-01

Compiled into this report are the activities and achievements of the center in fiscal 1997. Under study in the field of carbonaceous resources conversion reaction are the high-molecular coagulation structure, pyrolysis and carbonization, ignition, complex conversion of resources together with other resources, etc. Under study in the field of carbonaceous resources assessment are catalytic chemistry, organic chemistry, physical chemistry, and analytical chemistry. Under study in the field of the control of energy conversion are the generation of high-temperature thermal energy and its conversion into electromagnetic energy. In the study of ultimate materials engineering, materials are studied for use under hostile conditions such as in a nuclear fusion reactor. As for papers published in fiscal 1997, there are 18 in the field of carbonaceous resources conversion reaction, 10 in the field of carbonaceous resources assessment, 13 in the field of energy conversion control, and 17 in the field of ultimate materials engineering. Published also are 10 articles covering general remarks, interpretations, and reviews. As for academic lectures, 26 are given in the field of carbonaceous resources conversion reaction, 13 in the field of carbonaceous resources assessment, 29 in the field of energy conversion control, and 45 in the field of ultimate materials engineering. (NEDO)

Annual Report (No. 5) of Center for Advanced Research of Energy Technology, Hokkaido University; Hokkaido Daigaku energy sentan kogaku kenkyu center nenpo dai 5 go

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

Compiled into this report are the activities and achievements of the center in fiscal 1998. Under study in the field of carbonaceous resources conversion reaction are the high-molecular coagulation structure, pyrolysis and carbonization, ignition, complex conversion of resources together with other resources, etc. Under study in the field of carbonaceous resources assessment are catalytic chemistry, organic chemistry, physical chemistry, and analytical chemistry. Under study in the field of the control of energy conversion are the generation of high-temperature thermal energy and its conversion into electromagnetic energy. In the study of ultimate materials engineering, materials are studied for use under hostile conditions such as in a nuclear fusion reactor. As for papers published in fiscal 1998, there are 24 in the field of carbonaceous resources conversion reaction, 8 in the field of carbonaceous resources assessment, 10 in the field of energy conversion control, and 17 in the field of ultimate materials engineering. Published also are 4 articles covering general remarks, interpretations, and reviews. As for academic lectures, 21 are given in the field of carbonaceous resources conversion reaction, 25 in the field of carbonaceous resources assessment, 23 in the field of energy conversion control, and 47 in the field of ultimate materials engineering. (NEDO)

Annual progress report of the physical chemistry department. Basic research 1987

International Nuclear Information System (INIS)

1988-01-01

Basic research for 1987 in physical chemistry of the French Atomic Energy Commission are reviewed. Topics include molecular chemistry, isotopic geochemistry, molecular photophysics, laser photochemistry, solid and surface physical chemistry. A list of publications and thesis is given [fr

Computational Chemistry Comparison and Benchmark Database

Science.gov (United States)

SRD 101 NIST Computational Chemistry Comparison and Benchmark Database (Web, free access)   The NIST Computational Chemistry Comparison and Benchmark Database is a collection of experimental and ab initio thermochemical properties for a selected set of molecules. The goals are to provide a benchmark set of molecules for the evaluation of ab initio computational methods and allow the comparison between different ab initio computational methods for the prediction of thermochemical properties.

Metal-organic frameworks for analytical chemistry: from sample collection to chromatographic separation.

Science.gov (United States)

Gu, Zhi-Yuan; Yang, Cheng-Xiong; Chang, Na; Yan, Xiu-Ping

2012-05-15

In modern analytical chemistry researchers pursue novel materials to meet analytical challenges such as improvements in sensitivity, selectivity, and detection limit. Metal-organic frameworks (MOFs) are an emerging class of microporous materials, and their unusual properties such as high surface area, good thermal stability, uniform structured nanoscale cavities, and the availability of in-pore functionality and outer-surface modification are attractive for diverse analytical applications. This Account summarizes our research on the analytical applications of MOFs ranging from sampling to chromatographic separation. MOFs have been either directly used or engineered to meet the demands of various analytical applications. Bulk MOFs with microsized crystals are convenient sorbents for direct application to in-field sampling and solid-phase extraction. Quartz tubes packed with MOF-5 have shown excellent stability, adsorption efficiency, and reproducibility for in-field sampling and trapping of atmospheric formaldehyde. The 2D copper(II) isonicotinate packed microcolumn has demonstrated large enhancement factors and good shape- and size-selectivity when applied to on-line solid-phase extraction of polycyclic aromatic hydrocarbons in water samples. We have explored the molecular sieving effect of MOFs for the efficient enrichment of peptides with simultaneous exclusion of proteins from biological fluids. These results show promise for the future of MOFs in peptidomics research. Moreover, nanosized MOFs and engineered thin films of MOFs are promising materials as novel coatings for solid-phase microextraction. We have developed an in situ hydrothermal growth approach to fabricate thin films of MOF-199 on etched stainless steel wire for solid-phase microextraction of volatile benzene homologues with large enhancement factors and wide linearity. Their high thermal stability and easy-to-engineer nanocrystals make MOFs attractive as new stationary phases to fabricate MOF

Chemistry in water reactors

International Nuclear Information System (INIS)

Hermansson, H.P.; Norring, K.

1994-01-01

The international conference Chemistry in Water Reactors was arranged in Nice 24-27/04/1994 by the French Nuclear Energy Society. Examples of technical program areas were primary chemistry, operational experience, fundamental studies and new technology. Furthermore there were sessions about radiation field build-up, hydrogen chemistry, electro-chemistry, condensate polishing, decontamination and chemical cleaning. The conference gave the impression that there are some areas that are going to be more important than others during the next few years to come. Cladding integrity: Professor Ishigure from Japan emphasized that cladding integrity is a subject of great concern, especially with respect to waterside corrosion, deposition and release of crud. Chemistry control: The control of the iron/nickel concentration quotient seems to be not as important as previously considered. The future operation of a nuclear power plant is going to require a better control of the water chemistry than achievable today. One example of this is solubility control via regulation in BWR. Trends in USA: means an increasing use of hydrogen, minimization of SCC/IASCC, minimization of radiation fields by thorough chemistry control, guarding fuel integrity by minimization of cladding corrosion and minimization of flow assisted corrosion. Stellite replacement: The search for replacement materials will continue. Secondary side crevice chemistry: Modeling and practical studies are required to increase knowledge about the crevice chemistry and how it develops under plant operation conditions. Inhibitors: Inhibitors for IGSCC and IGA as well for the primary- (zinc) as for the secondary side (Ti) should be studied. The effects and mode of operation of the inhibitors should be documented. Chemical cleaning: of heat transfer surfaces will be an important subject. Prophylactic cleaning at regular intervals could be one mode of operation

Theoretical evaluation of high-energy lithium metal phosphate cathode materials in Li-ion batteries

Science.gov (United States)

Howard, Wilmont F.; Spotnitz, Robert M.

Lithium metal phosphates (olivines) are emerging as long-lived, safe cathode materials in Li-ion batteries. Nano-LiFePO 4 already appears in high-power applications, and LiMnPO 4 development is underway. Current and emerging Fe- and Mn-based intercalants, however, are low-energy producers compared to Ni and Co compounds. LiNiPO 4, a high voltage olivine, has the potential for superior energy output (>10.7 Wh in 18650 batteries), compared with commercial Li(Co,Ni)O 2 derivatives (up to 9.9 Wh). Speculative Co and Ni olivine cathode materials charged to above 4.5 V will require significant advances in electrolyte compositions and nanotechnology before commercialization. The major drivers toward 5 V battery chemistries are the inherent abuse tolerance of phosphates and the economic benefit of LiNiPO 4: it can produce 34% greater energy per dollar of cell material cost than LiAl 0.05Co 0.15Ni 0.8O 2, today's "standard" cathode intercalant in Li-ion batteries.

Frontiers of particle beam and high energy density plasma science using pulse power technology

International Nuclear Information System (INIS)

Masugata, Katsumi

2011-04-01

The papers presented at the symposium on “Frontiers of Particle Beam and High Energy Density Plasma Science using Pulse Power Technology” held in November 20-21, 2009 at National Institute for Fusion Science are collected. The papers reflect the present status and resent progress in the experiment and theoretical works on high power particle beams and high energy density plasmas produced by pulsed power technology. (author)

Beam Commissioning of the PEP-II High Energy Ring

International Nuclear Information System (INIS)

Wienands, U.; Anderson, S.; Assmann, R.; Bharadwaj, V.; Cai, Y.; Clendenin, J.; Corredoura, P.; Decker, F.J.; Donald, M.; Ecklund, S.; Emma, P.; Erickson, R.; Fox, J.; Fieguth, T.; Fisher, A.; Heifets, S.; Hill, A.; Himel, T.; Iverson, R.; Johnson, R.; Judkins, J.; Krejcik, P.; Kulikov, A.; Lee, M.; Mattison, T.; Minty, M.; Nosochkov, Y.; Phinney, N.; Placidi, M.; Prabhakar, S.; Ross, M.; Smith, S.; Schwarz, H.; Stanek, M.; Teytelman, D.; Traller, R.; Turner, J.; Zimmermann, F.; Barry, W.; Chattopadhyay, S.; Corlett, J.; Decking, W.; Furman, M.; Nishimura, H.; Portmann, G.; Rimmer, R.; Zholents, A.; Zisman, M.; Kozanecki, W.; Hofmann, A.; Zotter, B.; Steier, C.; Bialowons, W.; Lomperski, M.; Lumpkin, A.; Reichel, I.; Safranek, J.; Smith, V.; Tighe, R.; Sullivan, M.; Byrd, J.; Li, D.

1998-01-01

The PEP-II High Energy Ring (HER), a 9 GeV electron storage ring, has been in commissioning since spring 1997. Initial beam commissioning activities focused on systems checkout and commissioning and on determining the behavior of the machine systems at high beam currents. This phase culminated with the accumulation of 0.75 A of stored beam-sufficient to achieve design luminosity--in January 1998 after 3.5 months of beam time. Collisions with the 3 GeV positron beam of the Low Energy Ring (LER) were achieved in Summer of 1998. At high beam currents, collective instabilities have been seen. Since then, commissioning activities for the HER have shifted in focus towards characterization of the machine and a rigorous program to understand the machine and the beam dynamics is presently underway

Environmental Chemistry Compound Identification Using High ...

Science.gov (United States)

There is a growing need for rapid chemical screening and prioritization to inform regulatory decision-making on thousands of chemicals in the environment. We have previously used high-resolution mass spectrometry to examine household vacuum dust samples using liquid chromatography time-of-flight mass spectrometry (LC-TOF/MS). Using a combination of exact mass, isotope distribution, and isotope spacing, molecular features were matched with a list of chemical formulas from the EPA’s Distributed Structure-Searchable Toxicity (DSSTox) database. This has further developed our understanding of how openly available chemical databases, together with the appropriate searches, could be used for the purpose of compound identification. We report here on the utility of the EPA’s iCSS Chemistry Dashboard for the purpose of compound identification using searches against a database of over 720,000 chemicals. We also examine the benefits of QSAR prediction for the purpose of retention time prediction to allow for alignment of both chromatographic and mass spectral properties. This abstract does not reflect U.S. EPA policy presentation at the Eastern Analytical Symposium.

Review of high energy heavy ion experiments

International Nuclear Information System (INIS)

Miake, Yasuo

2000-01-01

It has been proposed that in high energy heavy ion collisions a physical conditions similar to the early stage of the Universe can be established in the laboratory. New phase of matter expected to be created is called the quark gluon plasma (QGP). Based on the motivation to create the QGP in the laboratory, heavy ion beams have been accelerated at AGS of Brookhaven National Laboratory and also at CERN-SPS. Several interesting features of the data have been reported, among which are: the suppression of J/ψ production in Pb+Pb collisions, the enhancement of low mass lepton pairs, and the collective behavior of hadron production. These features are reviewed under the key words of Deconfinement, Chiral Restoration and Collectivity in the lecture. (author)

Operational data collection and analysis for nuclear plant life extension

International Nuclear Information System (INIS)

DuCharme, A.R.; Berg, R.M.; Bailey, T.L.

1989-01-01

This paper describes initial work undertaken by the US Department of Energy, through Sandia National Laboratories in Albuquerque, New Mexico, to define the operational data necessary for support of nuclear plant life extension (PLEX) programs. This work is being performed in coordination with the Working Group on Plant Life Extension of the US Nuclear Management and Resources Council. The intent of the effort is to use results gained initially from pilot PLEX programs a US BWR and a US PWR to build towards the use of ''PLEX indicators'' by which a plant's readiness for successful life extension can be measured. Another objective of the study was to examine chemistry data in detail to determine how well US plants are collecting, preserving, and trending the chemistry data that is important to PLEX. The methods used to disseminate this data to outside agencies and other utilities were studied. Finally, an analysis was made to determine additional chemistry data needed to support PLEX

High energy neutron radiography

International Nuclear Information System (INIS)

Gavron, A.; Morley, K.; Morris, C.; Seestrom, S.; Ullmann, J.; Yates, G.; Zumbro, J.

1996-01-01

High-energy spallation neutron sources are now being considered in the US and elsewhere as a replacement for neutron beams produced by reactors. High-energy and high intensity neutron beams, produced by unmoderated spallation sources, open potential new vistas of neutron radiography. The authors discuss the basic advantages and disadvantages of high-energy neutron radiography, and consider some experimental results obtained at the Weapons Neutron Research (WNR) facility at Los Alamos

Machine learning of single molecule free energy surfaces and the impact of chemistry and environment upon structure and dynamics.

Science.gov (United States)

Mansbach, Rachael A; Ferguson, Andrew L

2015-03-14

The conformational states explored by polymers and proteins can be controlled by environmental conditions (e.g., temperature, pressure, and solvent) and molecular chemistry (e.g., molecular weight and side chain identity). We introduce an approach employing the diffusion map nonlinear machine learning technique to recover single molecule free energy landscapes from molecular simulations, quantify changes to the landscape as a function of external conditions and molecular chemistry, and relate these changes to modifications of molecular structure and dynamics. In an application to an n-eicosane chain, we quantify the thermally accessible chain configurations as a function of temperature and solvent conditions. In an application to a family of polyglutamate-derivative homopeptides, we quantify helical stability as a function of side chain length, resolve the critical side chain length for the helix-coil transition, and expose the molecular mechanisms underpinning side chain-mediated helix stability. By quantifying single molecule responses through perturbations to the underlying free energy surface, our approach provides a quantitative bridge between experimentally controllable variables and microscopic molecular behavior, guiding and informing rational engineering of desirable molecular structure and function.

International Congress on Analytical Chemistry. Abstracts. V. 1

International Nuclear Information System (INIS)

1997-01-01

The collection of materials of the international congress on analytical chemistry taken place in Moscow in June 1997. The main directs of investigations in such regions of analytical chemistry as quantitative and qualitative analysis, microanalysis, sample preparation and preconcentration, analytical reagents, chromatography and related techniques, flow analysis, electroanalytical and kinetic methods sensors are elucidated

Technetium Chemistry in HLW

International Nuclear Information System (INIS)

Hess, Nancy J.; Felmy, Andrew R.; Rosso, Kevin M.; Xia Yuanxian

2005-01-01

Tc contamination is found within the DOE complex at those sites whose mission involved extraction of plutonium from irradiated uranium fuel or isotopic enrichment of uranium. At the Hanford Site, chemical separations and extraction processes generated large amounts of high level and transuranic wastes that are currently stored in underground tanks. The waste from these extraction processes is currently stored in underground High Level Waste (HLW) tanks. However, the chemistry of the HLW in any given tank is greatly complicated by repeated efforts to reduce volume and recover isotopes. These processes ultimately resulted in mixing of waste streams from different processes. As a result, the chemistry and the fate of Tc in HLW tanks are not well understood. This lack of understanding has been made evident in the failed efforts to leach Tc from sludge and to remove Tc from supernatants prior to immobilization. Although recent interest in Tc chemistry has shifted from pretreatment chemistry to waste residuals, both needs are served by a fundamental understanding of Tc chemistry

Green Chemistry Challenge: 2017 Small Business Award

Science.gov (United States)

Green Chemistry Challenge 2017 award winner, UniEnergy,improved a vanadium redox flow battery to double the energy density, have a broader operating temperature range, a smaller footprint, reduced chemical usage, and very little capacity degradation.

The Living Textbook of Nuclear Chemistry

International Nuclear Information System (INIS)

Loveland, W.; Gallant, A.; Joiner, C.

2005-01-01

The Living Textbook of Nuclear Chemistry (http://livingtextbook.orst.edu) is a website, which is a collection of supplemental materials for the teaching of nuclear and radiochemistry. It contains audio-video presentations of the history of nuclear chemistry, tutorial lectures by recognized experts on advanced topics in nuclear and radiochemistry, links to data compilations, articles, and monographs, an audio course on radiochemistry, on-line editions of textbooks, training videos, etc. All content has been refereed. (author)

SPECIAL ISSUE DEDICATED TO THE 10TH ANNIVERSARY OF THE CHEMISTRY JOURNAL OF MOLDOVA. GENERAL, INDUSTRIAL AND ECOLOGICAL CHEMISTRY

OpenAIRE

Gheorghe DUCA

2016-01-01

Ten years ago, in 2006, CHEMISTRY JOURNAL OF MOLDOVA. General, Industrial and Ecological Chemistry was founded by the Institute of Chemistry of Academy of Sciences of Moldova and Moldova State University. Chemistry Journal of Moldova is an open access, international indexed and peer-reviewed journal that publishes papers of high quality containing original results in the areas of Chemical Sciences, such as analytical chemistry, ecological chemistry, food chemistry, industrial chem...

Undergraduate students' goals for chemistry laboratory coursework

Science.gov (United States)

DeKorver, Brittland K.

Chemistry laboratory coursework has the potential to offer many benefits to students, yet few of these learning goals are realized in practice. Therefore, this study seeks to characterize undergraduate students' learning goals for their chemistry laboratory coursework. Data were collected by recording video of students completing laboratory experiments and conducting interviews with the students about their experiences that were analyzed utilizing the frameworks of Human Constructivism and Self-Regulated Learning. A cross-sectional sampling of students allowed comparisons to be made among students with varying levels of chemistry experience and interest in chemistry. The student goals identified by this study were compared to previously described laboratory learning goals of the faculty who instruct these courses in an effort to identify potential avenues to improve laboratory learning.

What matters? Assessing and developing inquiry and multivariable reasoning skills in high school chemistry

Science.gov (United States)

Daftedar Abdelhadi, Raghda Mohamed

Although the Next Generation Science Standards (NGSS) present a detailed set of Science and Engineering Practices, a finer grained representation of the underlying skills is lacking in the standards document. Therefore, it has been reported that teachers are facing challenges deciphering and effectively implementing the standards, especially with regards to the Practices. This analytical study assessed the development of high school chemistry students' (N = 41) inquiry, multivariable causal reasoning skills, and metacognition as a mediator for their development. Inquiry tasks based on concepts of element properties of the periodic table as well as reaction kinetics required students to conduct controlled thought experiments, make inferences, and declare predictions of the level of the outcome variable by coordinating the effects of multiple variables. An embedded mixed methods design was utilized for depth and breadth of understanding. Various sources of data were collected including students' written artifacts, audio recordings of in-depth observational groups and interviews. Data analysis was informed by a conceptual framework formulated around the concepts of coordinating theory and evidence, metacognition, and mental models of multivariable causal reasoning. Results of the study indicated positive change towards conducting controlled experimentation, making valid inferences and justifications. Additionally, significant positive correlation between metastrategic and metacognitive competencies, and sophistication of experimental strategies, signified the central role metacognition played. Finally, lack of consistency in indicating effective variables during the multivariable prediction task pointed towards the fragile mental models of multivariable causal reasoning the students had. Implications for teacher education, science education policy as well as classroom research methods are discussed. Finally, recommendations for developing reform-based chemistry

Truncation of CPC solar collectors and its effect on energy collection

Science.gov (United States)

Carvalho, M. J.; Collares-Pereira, M.; Gordon, J. M.; Rabl, A.

1985-01-01

Analytic expressions are derived for the angular acceptance function of two-dimensional compound parabolic concentrator solar collectors (CPC's) of arbitrary degree of truncation. Taking into account the effect of truncation on both optical and thermal losses in real collectors, the increase in monthly and yearly collectible energy is also evaluated. Prior analyses that have ignored the correct behavior of the angular acceptance function at large angles for truncated collectors are shown to be in error by 0-2 percent in calculations of yearly collectible energy for stationary collectors.

International Congress on Analytical Chemistry. Abstracts. V. 2

International Nuclear Information System (INIS)

1997-01-01

The collection of materials of the international congress on analytical chemistry taken place in Moscow in June 1997 is presented. The main directs of investigations are elucidated in such regions of analytical chemistry as quantitative and qualitative chemical analysis, sample preparation, express test methods of environmental and biological materials, clinical analysis, analysis of food and agricultural products

International Congress on Analytical Chemistry. Abstracts. V. 2

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-12-31

The collection of materials of the international congress on analytical chemistry taken place in Moscow in June 1997 is presented. The main directs of investigations are elucidated in such regions of analytical chemistry as quantitative and qualitative chemical analysis, sample preparation, express test methods of environmental and biological materials, clinical analysis, analysis of food and agricultural products

Handbook of hot atom chemistry

International Nuclear Information System (INIS)

Adloff, J.P.; Matsuura, Tatsuo; Yoshihara, Kenji

1992-01-01

Hot atom chemistry is an increasingly important field, which has contributed significantly to our understanding of many fundamental processes and reactions. Its techniques have become firmly entrenched in numerous disciplines, such as applied physics, biomedical research, and all fields of chemistry. Written by leading experts, this comprehensive handbook encompasses a broad range of topics. Each chapter comprises a collection of stimulating essays, given an in-depth account of the state-of-the-art of the field, and stressing opportunities for future work. An extensive introduction to the whole area, this book provides unique insight into a vast subject, and a clear delineation of its goals, techniques, and recent findings. It also contains detailed discussions of applications in fields as diverse as nuclear medicine, geochemistry, reactor technology, and the chemistry of comets and interstellar grains. (orig.)

Collective mass and zero-point energy in the generator-coordinate method

International Nuclear Information System (INIS)

Fiolhais, C.

1982-01-01

The aim of the present thesis if the study of the collective mass parameters and the zero-point energies in the GCM framework with special regards to the fission process. After the derivation of the collective Schroedinger equation in the framework of the Gaussian overlap approximation the inertia parameters are compared with those of the adiabatic time-dependent Hartree-Fock method. Then the kinetic and the potential zero-point energy occurring in this formulation are studied. Thereafter the practical application of the described formalism is discussed. Then a numerical calculation of the GCM mass parameter and the zero-point energy for the fission process on the base of a two-center shell model with a pairing force in the BCS approximation is presented. (HSI) [de

Australian Chemistry Test Item Bank: Years 11 and 12. Volume 2.

Science.gov (United States)

Commons, C., Ed.; Martin, P., Ed.

The second volume of the Australian Chemistry Test Item Bank, consisting of two volumes, contains nearly 2000 multiple-choice items related to the chemistry taught in Year 11 and Year 12 courses in Australia. Items which were written during 1979 and 1980 were initially published in the "ACER Chemistry Test Item Collection" and in the…

Main concerns of CFTC about sustainable development applied to energy; Preoccupations essentielles de la CFTC sur le developpement durable applique a l'energie

Energy Technology Data Exchange (ETDEWEB)

Laffitte, O.

2003-07-01

In the framework of the French national debate on energies, this paper presents the main recommendations of the trade union for chemistry, mining, textile industry and energy industry of the French syndicate CFTC about the application of the sustainable development principles to the energy domain: the energy right for everyone, the importance of individual and collective liabilities in the domain of energy production and consumption, the necessity of an urgent legislative evolution at the European level, a sustainable policy of energy production, the problem of the energy consumption in transportation systems, the problem of security and safety in energy industries, the industrial strategy of companies in the energy sector. (J.S.)

Pre-Service Physics and Chemistry Teachers' Conceptual Integration of Physics and Chemistry Concepts

Science.gov (United States)

Tuysuz, Mustafa; Bektas, Oktay; Geban, Omer; Ozturk, Gokhan; Yalvac, Bugrahan

2016-01-01

This study examines the pre-service teachers' opinions about conceptual integration (CI) and their understanding of it. A qualitative phenomenology design was used in the study. Data was collected through in-depth semi-structured interviews comprising ten guiding questions. Three pre-service physics and three pre-service chemistry teachers…

Mendeleev-2013. VII All-Russian conference of young scientists, postgraduate students and students with international participation on chemistry and nanomaterials. Book of abstracts. Section 2. Analytic chemistry

International Nuclear Information System (INIS)

2013-01-01

VII All-Russian conference of young scientists, postgraduate students and students with international participation on chemistry and nanomaterials was conducted on the Chemistry department of Saint-Petersburg University on April, 2-5, 2013. In the conference participants from 14 countries took part. There were five sections: Nanochemistry and nanomaterials, Analytic chemistry, Inorganic chemistry, Organic chemistry, Physical chemistry. In the collection (Section 2 - Analytic chemistry) there are the abstracts concerning determination of heavy metals in environmental samples, petroleum products, different biological active and toxic substances in human tissues, food products and water; usage of nanoparticles for modification of electrodes for electrochemical methods of analysis, etc [ru

Final results of the FY'78 chemistry and materials science research program review

International Nuclear Information System (INIS)

Frazer, J.W.

1977-01-01

18 projects which were selected to be sponsored by ''Chemistry Research Program'' are summarized. These include: lasers for chemical analysis; multi-element analysis systems; spectroscopic analysis of surface passivation; non-aqueous titrimetry; materials damage prediction for fiber composites; safe high energy explosives; single photon absorption reaction chemistry; reaction in shock waves; cryogenic heavy hydrogen technology; acoustic emission; metallic alloy glasses; basic study of toughness in steel; static equation-of-state at 100 GPa; transuranium element research; nuclear structure research; neutron capture gamma measurements; x-ray fluorescence analysis; and pyrochemical investigation

High to ultra-high power electrical energy storage.

Science.gov (United States)

Sherrill, Stefanie A; Banerjee, Parag; Rubloff, Gary W; Lee, Sang Bok

2011-12-14

High power electrical energy storage systems are becoming critical devices for advanced energy storage technology. This is true in part due to their high rate capabilities and moderate energy densities which allow them to capture power efficiently from evanescent, renewable energy sources. High power systems include both electrochemical capacitors and electrostatic capacitors. These devices have fast charging and discharging rates, supplying energy within seconds or less. Recent research has focused on increasing power and energy density of the devices using advanced materials and novel architectural design. An increase in understanding of structure-property relationships in nanomaterials and interfaces and the ability to control nanostructures precisely has led to an immense improvement in the performance characteristics of these devices. In this review, we discuss the recent advances for both electrochemical and electrostatic capacitors as high power electrical energy storage systems, and propose directions and challenges for the future. We asses the opportunities in nanostructure-based high power electrical energy storage devices and include electrochemical and electrostatic capacitors for their potential to open the door to a new regime of power energy.

Detection systems for high energy particle producing gaseous ionization

International Nuclear Information System (INIS)

Martinez, L.; Duran, I.

1985-01-01

This report contains a review on the most used detectors based on the collection of the ionization produced by high energy particles: proportional counters, multiwire proportional chambers, Geiger-Muller counters and drift chambers. In six sections, the fundamental principles, the field configuration and useful gas mixtures, are discussed, most relevant devices are reported along 90 pages with 98 references. (Author) 98 refs

Low-Achieving Students' Attitudes towards Learning Chemistry and Chemistry Teaching Methods

Science.gov (United States)

Kousa, P.; Kavonius, R.; Aksela, M.

2018-01-01

The aims of this study were to determine low-achieving students' attitudes towards chemistry and how the attitudes differ within a low achieving group. The most preferred teaching methods were also defined. Empirical data (n = 2949) were collected by stratified sampling from fifteen-year-old Finnish lower-secondary school students as part of a…

High-energy detector

Science.gov (United States)

Bolotnikov, Aleksey E [South Setauket, NY; Camarda, Giuseppe [Farmingville, NY; Cui, Yonggang [Upton, NY; James, Ralph B [Ridge, NY

2011-11-22

The preferred embodiments are directed to a high-energy detector that is electrically shielded using an anode, a cathode, and a conducting shield to substantially reduce or eliminate electrically unshielded area. The anode and the cathode are disposed at opposite ends of the detector and the conducting shield substantially surrounds at least a portion of the longitudinal surface of the detector. The conducting shield extends longitudinally to the anode end of the detector and substantially surrounds at least a portion of the detector. Signals read from one or more of the anode, cathode, and conducting shield can be used to determine the number of electrons that are liberated as a result of high-energy particles impinge on the detector. A correction technique can be implemented to correct for liberated electron that become trapped to improve the energy resolution of the high-energy detectors disclosed herein.

Energy Systems High-Pressure Test Laboratory | Energy Systems Integration

Science.gov (United States)

Facility | NREL Energy Systems High-Pressure Test Laboratory Energy Systems High-Pressure Test Laboratory In the Energy Systems Integration Facility's High-Pressure Test Laboratory, researchers can safely test high-pressure hydrogen components. Photo of researchers running an experiment with a hydrogen fuel

Proton radioactivity at non-collective prolate shape in high spin state of 94Ag

International Nuclear Information System (INIS)

Aggarwal, Mamta

2010-01-01

We predict proton radioactivity and structural transitions in high spin state of an excited exotic nucleus near proton drip line in a theoretical framework and investigate the nature and the consequences of the structural transitions on separation energy as a function of temperature and spin. It reveals that the rotation of the excited exotic nucleus 94 Ag at excitation energies around 6.7 MeV and angular momentum near 21h generates a rarely seen prolate non-collective shape and proton separation energy becomes negative which indicates proton radioactivity in agreement with the experimental results of Mukha et al. for 94 Ag.

Substantial difference in target surface chemistry between reactive dc and high power impulse magnetron sputtering

Science.gov (United States)

Greczynski, G.; Mráz, S.; Schneider, J. M.; Hultman, L.

2018-02-01

The nitride layer formed in the target race track during the deposition of stoichiometric TiN thin films is a factor 2.5 thicker for high power impulse magnetron sputtering (HIPIMS), compared to conventional dc processing (DCMS). The phenomenon is explained using x-ray photoelectron spectroscopy analysis of the as-operated Ti target surface chemistry supported by sputter depth profiles, dynamic Monte Carlo simulations employing the TRIDYN code, and plasma chemical investigations by ion mass spectrometry. The target chemistry and the thickness of the nitride layer are found to be determined by the implantation of nitrogen ions, predominantly N+ and N2+ for HIPIMS and DCMS, respectively. Knowledge of this method-inherent difference enables robust processing of high quality functional coatings.

High-speed and high-fidelity system and method for collecting network traffic

Science.gov (United States)

Weigle, Eric H [Los Alamos, NM

2010-08-24

A system is provided for the high-speed and high-fidelity collection of network traffic. The system can collect traffic at gigabit-per-second (Gbps) speeds, scale to terabit-per-second (Tbps) speeds, and support additional functions such as real-time network intrusion detection. The present system uses a dedicated operating system for traffic collection to maximize efficiency, scalability, and performance. A scalable infrastructure and apparatus for the present system is provided by splitting the work performed on one host onto multiple hosts. The present system simultaneously addresses the issues of scalability, performance, cost, and adaptability with respect to network monitoring, collection, and other network tasks. In addition to high-speed and high-fidelity network collection, the present system provides a flexible infrastructure to perform virtually any function at high speeds such as real-time network intrusion detection and wide-area network emulation for research purposes.

High energy lithium-oxygen batteries - Transport barriers and thermodynamics

KAUST Repository

Das, Shyamal K.

2012-01-01

We show that it is possible to achieve higher energy density lithium-oxygen batteries by simultaneously lowering the discharge overpotential and increasing the discharge capacity via thermodynamic variables alone. By assessing the relative effects of temperature and pressure on the cell discharge profiles, we characterize and diagnose the critical roles played by multiple dynamic processes that have hindered implementation of the lithium-oxygen battery. © 2012 The Royal Society of Chemistry.

Nuclear chemistry research for the safe disposal of nuclear waste

International Nuclear Information System (INIS)

Fanghaenel, Thomas

2011-01-01

The safe disposal of high-level nuclear waste and spent nuclear fuel is of key importance for the future sustainable development of nuclear energy. Concepts foresee the isolation of the nuclear waste in deep geological formations. The long-term radiotoxicity of nuclear waste is dominated by plutonium and the minor actinides. Hence it is essential for the performance assessment of a nuclear waste disposal to understand the chemical behaviour of actinides in a repository system. The aqueous chemistry and thermodynamics of actinides is rather complex in particular due to their very rich redox chemistry. Recent results of our detailed study of the Plutonium and Neptunium redox - and complexation behaviour are presented and discussed. (author)

A New Vision for Chemistry Education Students: Environmental Education

Science.gov (United States)

Teksoz, Gaye; Sahin, Elvan; Ertepinar, Hamide

2010-01-01

The present study aimed to determine level of pre-service chemistry teachers' environmental literacy and their perceptions on environmental education. This study was realized during the fall semester of 2006-2007 academic year with the participation of 60 students enrolled in five-year chemistry teacher education program. The data collected by…

Electron energy distributions and excitation rates in high-frequency argon discharges

International Nuclear Information System (INIS)

Ferreira, C.M.; Loureiro, J.

1983-06-01

The electron energy distribution functions and rate coefficients for excitation and ionisation in argon under the action of an uniform high-frequency electric field were calculated by numerically solving the homogeneous Boltzmann equation. Analytic calculations in the limiting cases ω>>νsub(c) and ω<<νsub(c), where ω is the wave angular frequency and νsub(c) is the electron-neutral collision frequency for momentum transfer, are also presented and shown to be in very good agreement with the numerical computations. The results reported here are relevant for the modelling of high-frequency discharges in argon and, in particular, for improving recent theoretical descriptions of a plasma column sustained by surface microwaves. The properties of surface wave produced plasmas make them interesting as possible substitutes for other more conventional plasma sources for such important applications as plasma chemistry laser excitation, plasma etching spectroscopic sources etc...

High Returns, Low Attention, Slow Implementation: The Policy Paradoxes of India's Clean Energy Development

International Nuclear Information System (INIS)

Charnoz, Olivier; Swain, Ashwini

2012-07-01

India claims to be undertaking a thorough transition to low-carbon electricity, stepping up renewable energy and energy efficiency efforts. Yet, two puzzling paradoxes weigh upon this dynamic. First, although energy efficiency measures offer high collective returns, at least as high as those for renewable energy, the energy efficiency agenda is receiving a lot less attention and priority, even though it would require significantly less investment. Second, within the energy efficiency domain, implementation is lower and slower in sectors where the savings potential is the highest, notably among agricultural and domestic (household) consumers. Drawing on a range of interviews, documentary analysis and policy observations, this paper helps to shed light on this conundrum. In particular, it points out the discrepancy between individual and collective incentives in promoting energy efficiency, the biases and weaknesses of Indian governance at both the central and state levels, the influence of lobbies, the weight of parallel governmental agendas, and the built-in preference of the government, as well as international donors, for a technological rather than a governance focus. Nonetheless, striking a new balance between energy efficiency and renewable energy as complementary agendas is of crucial importance if India is to achieve its developmental, social, environmental and energy security goals. (authors)

The Separate and Collective Effects of Personalization, Personification, and Gender on Learning with Multimedia Chemistry Instructional Materials

Science.gov (United States)

Halkyard, Shannon

2012-01-01

Chemistry is a difficult subject to learn and teach for students in general. Additionally, female students are under-represented in chemistry and the physical sciences. Within chemistry, atomic and electronic structure is a key concept and several recommendations in the literature describe how this topic can be taught better. These recommendations…

Very high energy colliders

International Nuclear Information System (INIS)

Richter, B.

1986-03-01

The luminosity and energy requirements are considered for both proton colliders and electron-positron colliders. Some of the basic design equations for high energy linear electron colliders are summarized, as well as design constraints. A few examples are given of parameters for very high energy machines. 4 refs., 6 figs

Critical Chemistry Education in a Private, Suburban High School

Science.gov (United States)

Ashby, Patrick; Mensah, Felicia Moore

2018-01-01

This critical ethnography documents how a group of 25 students and their teacher/researcher in a suburban, private school setting, the vast majority from the dominant cultural background, engaged with and enacted a critical chemistry education together. Critical chemistry education contextualizes chemistry in socially relevant issues and problematizes participants' conceptual frameworks for understanding the intersections between chemistry and our capitalist society by identifying the shortcomings of traditional scientific language to sufficiently interrogate privilege and oppression. Qualitative data from teacher/researcher field notes and journal, classroom video transcripts, questionnaires, focus group interviews, and student artifacts document that while it is difficult for the teacher/researcher and the students of this setting to reflect upon their own positions of privilege, together they interpreted and made meaning of their experience by (1) developing the ability to critically analyze the products of science for the potential of oppression, (2) developing an understanding of inequity in science, and (3) evaluating and respecting diverse knowledge bases. Based on the findings, we suggest students should be encouraged to problematize socially situated science issues related to settings close to their own communities, students should participate in structured and purposeful journaling to improve their metacognition and critical reflexivity, and critical pedagogues must be explicit with students in their Marxist-based interpretation of the global capitalist super structure.

The link between physics and chemistry in track modelling

International Nuclear Information System (INIS)

Green, N.J.B.; Bolton, C.E.; Spencer-Smith, R.D.

1999-01-01

The physical structure of a radiation track provides the initial conditions for the modelling of radiation chemistry. These initial conditions are not perfectly understood, because there are important gaps between what is provided by a typical track structure model and what is required to start the chemical model. This paper addresses the links between the physics and chemistry of tracks, with the intention of identifying those problems that need to be solved in order to obtain an accurate picture of the initial conditions for the purposes of modelling chemistry. These problems include the reasons for the increased yield of ionisation relative to homolytic bond breaking in comparison with the gas phase. A second area of great importance is the physical behaviour of low-energy electrons in condensed matter (including thermolisation and solvation). Many of these processes are not well understood, but they can have profound effects on the transient chemistry in the track. Several phenomena are discussed, including the short distance between adjacent energy loss events, the molecular nature of the underlying medium, dissociative attachment resonances and the ability of low-energy electrons to excite optically forbidden molecular states. Each of these phenomena has the potential to modify the transient chemistry substantially and must therefore be properly characterised before the physical model of the track can be considered to be complete. (orig.)

Actinide separation chemistry in nuclear waste streams and materials

International Nuclear Information System (INIS)

1997-12-01

The separation of actinide elements from various waste materials, produced either in nuclear fuel cycles or in past nuclear weapons production, represents a significant issue facing developed countries. Improvements in the efficiencies of the separation processes can be expected to occur as a result of better knowledge of the elements in these complex matrices. The Nuclear Science Committee of the OECD/NEA has established a task force of experts in actinide separation chemistry to review current and developing separation techniques and chemical processes. The report consist of eight chapters. In Chapter 1 the importance of actinide separation chemistry in the fields of waste management and its background are summarized.In Chapter 2 the types of waste streams are classified according to their relative importance, by physical form and by source of actinides. The basic data of actinide chemical thermodynamics, such as oxidation states, hydrolysis, complexation, sorption, Gibbs energies of formation, and volatility, were collected and are presented in Chapter 3. Actinide analyses related to separation processes are also mentioned in this chapter. The state of the art of actinide separation chemistry is classified in three groups, including hydrometallurgy, pyrochemical process and process based on fields, and is described in Chapter 4 along with the relationship of kinetics to separations. In Chapter 5 basic chemistry research needs and the inherent limitation on separation processes are discussed. Prioritization of research and development is discussed in Chapter 6 in the context of several attributes of waste management problems. These attributes include: mass or volume of waste; concentration of the actinide in the waste; expected difficulty of treating the wastes; short-term hazard of the waste; long-term hazard of the waste; projected cost of treatment; amount of secondary waste. Based on the priority, recommendations were made for the direction of future research

Actinide separation chemistry in nuclear waste streams and materials

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-12-01

The separation of actinide elements from various waste materials, produced either in nuclear fuel cycles or in past nuclear weapons production, represents a significant issue facing developed countries. Improvements in the efficiencies of the separation processes can be expected to occur as a result of better knowledge of the elements in these complex matrices. The Nuclear Science Committee of the OECD/NEA has established a task force of experts in actinide separation chemistry to review current and developing separation techniques and chemical processes. The report consist of eight chapters. In Chapter 1 the importance of actinide separation chemistry in the fields of waste management and its background are summarized.In Chapter 2 the types of waste streams are classified according to their relative importance, by physical form and by source of actinides. The basic data of actinide chemical thermodynamics, such as oxidation states, hydrolysis, complexation, sorption, Gibbs energies of formation, and volatility, were collected and are presented in Chapter 3. Actinide analyses related to separation processes are also mentioned in this chapter. The state of the art of actinide separation chemistry is classified in three groups, including hydrometallurgy, pyrochemical process and process based on fields, and is described in Chapter 4 along with the relationship of kinetics to separations. In Chapter 5 basic chemistry research needs and the inherent limitation on separation processes are discussed. Prioritization of research and development is discussed in Chapter 6 in the context of several attributes of waste management problems. These attributes include: mass or volume of waste; concentration of the actinide in the waste; expected difficulty of treating the wastes; short-term hazard of the waste; long-term hazard of the waste; projected cost of treatment; amount of secondary waste. Based on the priority, recommendations were made for the direction of future research

Detecting ultra high energy neutrinos with LOFAR

International Nuclear Information System (INIS)

Mevius, M.; Buitink, S.; Falcke, H.; Hörandel, J.; James, C.W.; McFadden, R.; Scholten, O.; Singh, K.; Stappers, B.; Veen, S. ter

2012-01-01

The NuMoon project aims to detect signals of Ultra High Energy (UHE) Cosmic Rays with radio telescopes on Earth using the Lunar Cherenkov technique at low frequencies (∼150MHz). The advantage of using low frequencies is the much larger effective detecting volume, with as trade-off the cut-off in sensitivity at lower energies. A first upper limit on the UHE neutrino flux from data of the Westerbork Radio Telescope (WSRT) has been published, while a second experiment, using the new LOFAR telescope, is in preparation. The advantages of LOFAR over WSRT are the larger collecting area, the better pointing accuracy and the use of ring buffers, which allow the implementation of a sophisticated self-trigger algorithm. The expected sensitivity of LOFAR reaches flux limits within the range of some theoretical production models.

Reversible aqueous zinc/manganese oxide energy storage from conversion reactions

Energy Technology Data Exchange (ETDEWEB)

Pan, Huilin; Shao, Yuyan; Yan, Pengfei; Cheng, Yingwen; Han, Kee Sung; Nie, Zimin; Wang, Chongmin; Yang, Jihui; Li, Xiaolin; Bhattacharya, Priyanka; Mueller, Karl T.; Liu, Jun

2016-04-18

Rechargeable aqueous batteries are attracting growing interest for energy storage due to their low cost and high safety. Fundamental understanding of highly reversible aqueous reactions is critical for building high-performance batteries. Herein, we studied the reversibility of Zn/MnO2 battery chemistry in mild aqueous MnSO4 electrolytes. α-MnO2 nanofibers were used as a high performance cathode. Our study provides good evidence for a conversion reaction mechanism through reversible formation of short nanorods and nanoparticle aggregates. This reversible conversion reaction provides an operating voltage of 1.44 V, high capacity of 285 mAh g-1, excellent rate and capacity retention of 92% after 5000 cycles. Zn metal anode also shows high reversibility in the mild aqueous MnSO4 electrolytes. The highly reversible and stable chemistries in aqueous Zn/MnO2 batteries open new opportunity for energy storage technologies with potentially high energy density, high safety, and low cost.

Linking the microscopic view of chemistry to real-life experiences: Intertextuality in a high-school science classroom

Science.gov (United States)

Wu, Hsin-Kai

2003-11-01

Chemistry learning involves establishing conceptual relationships among macroscopic, microscopic, and symbolic representations. Employing the notion of intertextuality to conceptualize these relationships, this study investigates how class members interactionally construct meanings of chemical representations by connecting them to real-life experiences and how the teachers' content knowledge shapes their ways to coconstruct intertextual links with students. Multiple sources of data were collected over 7 weeks with a participation of 25 eleventh graders, an experienced teacher, and a student teacher. An examination of classroom discourse shows that the intertextual links between the microscopic view of chemistry and students' real-life experiences could be initiated by students and instigated by the teachers. The teachers applied several discursive strategies to scaffold students building meaningful links based on their prior knowledge and experiences. Additionally, the experienced teacher with stronger content knowledge tended to present links in both dialogic and monologic discourses. Yet, the relatively limited content knowledge did not necessarily constrain the student teacher's interactions with students. The findings of this study provide a backdrop for further research to explore how chemistry is learned and taught in a class through the social constructivist lens.

A qualitative inquiry into the effects of visualization on high school chemistry students' learning process of molecular structure

Science.gov (United States)

Deratzou, Susan

This research studies the process of high school chemistry students visualizing chemical structures and its role in learning chemical bonding and molecular structure. Minimal research exists with high school chemistry students and more research is necessary (Gabel & Sherwood, 1980; Seddon & Moore, 1986; Seddon, Tariq, & Dos Santos Veiga, 1984). Using visualization tests (Ekstrom, French, Harman, & Dermen, 1990a), a learning style inventory (Brown & Cooper, 1999), and observations through a case study design, this study found visual learners performed better, but needed more practice and training. Statistically, all five pre- and post-test visualization test comparisons were highly significant in the two-tailed t-test (p > .01). The research findings are: (1) Students who tested high in the Visual (Language and/or Numerical) and Tactile Learning Styles (and Social Learning) had an advantage. Students who learned the chemistry concepts more effectively were better at visualizing structures and using molecular models to enhance their knowledge. (2) Students showed improvement in learning after visualization practice. Training in visualization would improve students' visualization abilities and provide them with a way to think about these concepts. (3) Conceptualization of concepts indicated that visualizing ability was critical and that it could be acquired. Support for this finding was provided by pre- and post-Visualization Test data with a highly significant t-test. (4) Various molecular animation programs and websites were found to be effective. (5) Visualization and modeling of structures encompassed both two- and three-dimensional space. The Visualization Test findings suggested that the students performed better with basic rotation of structures as compared to two- and three-dimensional objects. (6) Data from observations suggest that teaching style was an important factor in student learning of molecular structure. (7) Students did learn the chemistry concepts

Directory of Energy Data Collection Forms: Forms in use as of October 1996

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-12-01

This is the twentieth edition of the Directory of Energy Collection Data Forms, an authoritative listing of selected public use forms currently used as basic energy information gathering tools by the Department of Energy.

Solvothermal method as a green chemistry solution for micro-encapsulation of phase change materials for high temperature thermal energy storage

Directory of Open Access Journals (Sweden)

Tudor Albert Ioan

2018-01-01

Full Text Available Thermal energy storage systems using phase change materials (PCMs as latent heat storage are one of the main challenges at European level in improving the performances and efficiency of concentrated solar power energy generation due to their high energy density. PCM with high working temperatures in the temperature range 300–500 °C are required for these purposes. However their use is still limited due to the problems raised by the corrosion of the majority of high temperature PCMs and lower thermal transfer properties. Micro-encapsulation was proposed as one method to overcome these problems. Different micro-encapsulation methods proposed in the literature are presented and discussed. An original process for the micro-encapsulation of potassium nitrate as PCM in inorganic zinc oxide shells based on a solvothermal method followed by spray drying to produce microcapsules with controlled phase composition and distribution is proposed and their transformation temperatures and enthalpies measured by differential scanning calorimetry are presented.

Solvothermal method as a green chemistry solution for micro-encapsulation of phase change materials for high temperature thermal energy storage

Science.gov (United States)

Tudor, Albert Ioan; Motoc, Adrian Mihail; Ciobota, Cristina Florentina; Ciobota, Dan. Nastase; Piticescu, Radu Robert; Romero-Sanchez, Maria Dolores

2018-05-01

Thermal energy storage systems using phase change materials (PCMs) as latent heat storage are one of the main challenges at European level in improving the performances and efficiency of concentrated solar power energy generation due to their high energy density. PCM with high working temperatures in the temperature range 300-500 °C are required for these purposes. However their use is still limited due to the problems raised by the corrosion of the majority of high temperature PCMs and lower thermal transfer properties. Micro-encapsulation was proposed as one method to overcome these problems. Different micro-encapsulation methods proposed in the literature are presented and discussed. An original process for the micro-encapsulation of potassium nitrate as PCM in inorganic zinc oxide shells based on a solvothermal method followed by spray drying to produce microcapsules with controlled phase composition and distribution is proposed and their transformation temperatures and enthalpies measured by differential scanning calorimetry are presented.

Real time water chemistry monitoring and diagnostics

International Nuclear Information System (INIS)

Gaudreau, T.M.; Choi, S.S.

2002-01-01

EPRI has produced a real time water chemistry monitoring and diagnostic system. This system is called SMART ChemWorks and is based on the EPRI ChemWorks codes. System models, chemistry parameter relationships and diagnostic approaches from these codes are integrated with real time data collection, an intelligence engine and Internet technologies to allow for automated analysis of system chemistry. Significant data management capabilities are also included which allow the user to evaluate data and create automated reporting. Additional features have been added to the system in recent years including tracking and evaluation of primary chemistry as well as the calculation and tracking of primary to secondary leakage in PWRs. This system performs virtual sensing, identifies normal and upset conditions, and evaluates the consistency of on-line monitor and grab sample readings. The system also makes use of virtual fingerprinting to identify the cause of any chemistry upsets. This technology employs plant-specific data and models to determine the chemical state of the steam cycle. (authors)

Error identification in a high-volume clinical chemistry laboratory: Five-year experience.

Science.gov (United States)

Jafri, Lena; Khan, Aysha Habib; Ghani, Farooq; Shakeel, Shahid; Raheem, Ahmed; Siddiqui, Imran

2015-07-01

Quality indicators for assessing the performance of a laboratory require a systematic and continuous approach in collecting and analyzing data. The aim of this study was to determine the frequency of errors utilizing the quality indicators in a clinical chemistry laboratory and to convert errors to the Sigma scale. Five-year quality indicator data of a clinical chemistry laboratory was evaluated to describe the frequency of errors. An 'error' was defined as a defect during the entire testing process from the time requisition was raised and phlebotomy was done until the result dispatch. An indicator with a Sigma value of 4 was considered good but a process for which the Sigma value was 5 (i.e. 99.977% error-free) was considered well controlled. In the five-year period, a total of 6,792,020 specimens were received in the laboratory. Among a total of 17,631,834 analyses, 15.5% were from within hospital. Total error rate was 0.45% and of all the quality indicators used in this study the average Sigma level was 5.2. Three indicators - visible hemolysis, failure of proficiency testing and delay in stat tests - were below 5 on the Sigma scale and highlight the need to rigorously monitor these processes. Using Six Sigma metrics quality in a clinical laboratory can be monitored more effectively and it can set benchmarks for improving efficiency.

78 FR 59661 - Revision of a Currently Approved Information Collection for the State Energy Program

Science.gov (United States)

2013-09-27

... the final version of the information collection request. The Department of Energy (DOE) invites public... information collection requests a revision and three-year extension of its State Energy Program, OMB Control...

Energy-delay trade-off of wireless data collection in the plane

NARCIS (Netherlands)

Mitici, M.A.; Goseling, Jasper; de Graaf, Maurits; Boucherie, Richardus J.

2014-01-01

We analyze the Pareto front of the delay of collecting data from wireless devices located in the plane according to a Poisson process and the energy needed by the devices to transmit their observations. Fundamental bounds on the energy-delay trade-off over the space of all achievable scheduling

Free Energy Minimization Calculation of Complex Chemical Equilibria. Reduction of Silicon Dioxide with Carbon at High Temperature.

Science.gov (United States)

Wai, C. M.; Hutchinson, S. G.

1989-01-01

Discusses the calculation of free energy in reactions between silicon dioxide and carbon. Describes several computer programs for calculating the free energy minimization and their uses in chemistry classrooms. Lists 16 references. (YP)

Mechanistic aspects of polymer chemistry for radiation curing

International Nuclear Information System (INIS)

Dickson, Lawrence W.

1988-01-01

The chemistry of polymer production has been reviewed for the purpose of identifying suitable uses for high-energy electron accelerators in the plastics industry. High-energy radiation produces free radicals, electrons and ions in irradiated materials. These species initiate polymerization and cross-linking reactions in a manner analogous to that of chemical agents. The chemical mechanisms of radiation-induced polymerization, co-polymerization and cross-linking are compared with those of chemical and thermal initiation. Radiation polymerization can be a very fast process, but the polymerization reactions are quite exothermic, and temperature increases of up to 400 degrees Celcius may result if insufficient cooling is provided. Several approaches to reducing the temperature increase during radiation curing are presented. Chemical kinetic simulations of the radiation-induced cationic polymerization of styrene have shown that the effect of water inhibition on the rate of polymerization may be eliminated at the high dose rates available from high power accelerators. 25 refs

Hispanic-American Students' Attitudes toward Enrolling in High School Chemistry: A Study of Planned Behavior and Belief-Based Change.

Science.gov (United States)

Crawley, Frank E.; Koballa, Thomas R., Jr.

The study sought to: (1) identify the determinants that motivate Hispanic-American students to enroll in high school chemistry; and (2) determine if providing belief-based information to students and their parents/guardians increases chemistry registration. The Theory of Planned Behavior (TPB) and Elaboration Likelihood Model (ELM) guided the…

Interfacing detectors and collecting data for large-scale experiments in high energy physics using COTS technology

International Nuclear Information System (INIS)

Schumacher, Joern

2017-01-01

Data-acquisition systems for high-energy physics experiments like the ATLAS experiment at the European particle-physics research institute CERN are used to record experimental physics data and are essential for the effective operation of an experiment. Located in underground facilities with limited space, power, cooling, and exposed to ionizing radiation and strong magnetic fields, data-acquisition systems have unique requirements and are challenging to design and build. Traditionally, these systems have been composed of custom-designed electronic components to be able to cope with the large data volumes that high-energy physics experiments generate and at the same time meet technological and environmental requirements. Custom-designed electronics is costly to develop,effortful to maintain and typically not very flexible. This thesis explores an alternative architecture for data-acquisition systems based on commercial off-the-shelf (COTS) components. A COTS-based data distribution device called FELIX that will be integrated in ATLAS is presented. The hardware and software implementation of this device is discussed, with a specific focus on performance, heterogenity of systems and traffic patterns. The COTS-based readout approach is evaluated in the context of the future requirements of the ATLAS experiment. The main contributions of the thesis are an analysis of the ATLAS data-acquisition system with a focus on the readout system, a software architecture for the main application on FELIX hosts, a performance analysis and tuning based on computer science methods for central FELIX software components with respect to the requirements of the ATLAS experiment, a network communication library with a high-level software interface to utilize high-performance computing network technology for the purpose of data-acquisition systems, and an evaluation and discussion of ATLAS data-acquisition using FELIX systems as a case study for COTS-based data-acquisition in high-energy

Interfacing detectors and collecting data for large-scale experiments in high energy physics using COTS technology

Energy Technology Data Exchange (ETDEWEB)

Schumacher, Joern

2017-07-01

Data-acquisition systems for high-energy physics experiments like the ATLAS experiment at the European particle-physics research institute CERN are used to record experimental physics data and are essential for the effective operation of an experiment. Located in underground facilities with limited space, power, cooling, and exposed to ionizing radiation and strong magnetic fields, data-acquisition systems have unique requirements and are challenging to design and build. Traditionally, these systems have been composed of custom-designed electronic components to be able to cope with the large data volumes that high-energy physics experiments generate and at the same time meet technological and environmental requirements. Custom-designed electronics is costly to develop,effortful to maintain and typically not very flexible. This thesis explores an alternative architecture for data-acquisition systems based on commercial off-the-shelf (COTS) components. A COTS-based data distribution device called FELIX that will be integrated in ATLAS is presented. The hardware and software implementation of this device is discussed, with a specific focus on performance, heterogenity of systems and traffic patterns. The COTS-based readout approach is evaluated in the context of the future requirements of the ATLAS experiment. The main contributions of the thesis are an analysis of the ATLAS data-acquisition system with a focus on the readout system, a software architecture for the main application on FELIX hosts, a performance analysis and tuning based on computer science methods for central FELIX software components with respect to the requirements of the ATLAS experiment, a network communication library with a high-level software interface to utilize high-performance computing network technology for the purpose of data-acquisition systems, and an evaluation and discussion of ATLAS data-acquisition using FELIX systems as a case study for COTS-based data-acquisition in high-energy

Nanostructured energy devices equilibrium concepts and kinetics

CERN Document Server

Bisquert, Juan

2014-01-01

Due to the pressing needs of society, low cost materials for energy devices have experienced an outstanding development in recent times. In this highly multidisciplinary area, chemistry, material science, physics, and electrochemistry meet to develop new materials and devices that perform required energy conversion and storage processes with high efficiency, adequate capabilities for required applications, and low production cost. Nanostructured Energy Devices: Equilibrium Concepts and Kinetics introduces the main physicochemical principles that govern the operation of energy devices. It inclu

High energy physics advisory panel's subpanel on vision for the future of high-energy physics

International Nuclear Information System (INIS)

1994-05-01

This report was requested by the Secretary of Energy to (1) define a long-term program for pursuing the most important high-energy physics goals since the termination of the Superconducting Super Collider (SSC) project, (2) assess the current US high-energy physics program, and (3) make recommendations regarding the future of the field. Subjects on which recommendations were sought and which the report addresses were: high-energy physics funding priorities; facilitating international collaboration for future construction of large high-energy physics facilities; optimizing uses of the investment made in the SSC; how to encourage displaced scientists and engineers to remain in high-energy physics and to attract young scientists to enter the field in the future. The report includes a description of the state of high-energy physics research in the context of history, a summary of the SSC project, and documentation of the report's own origins and development

High energy halogen atom reactions activated by nuclear transformations. Progress report, February 15-December 31, 1984

International Nuclear Information System (INIS)

1985-01-01

Energetic halogen atoms or ions, activated by various nuclear transformations are studied in gas, high pressure and condensed phase saturated and unsaturated hydrocarbons, halomethanes, and liquid and solid aqueous solutions of biomolecular and organic solutes in order to understand better the mechanisms and dynamics of high energy monovalent species. The experimental program and its goals remain the same, consisting of four interrelated areas: (1) The stereochemistry of energetic 18 F, /sup 34m/Cl, and 38 Cl substitution reactions with chiral molecules in the gas and condensed phase is studied. (2) The gas to condensed state transition in halogen high energy chemistry, involving energetic chlorine, bromine, and iodine reactions in halomethanes, saturated and unsaturated hydrocarbons and aqueous solutions of biomolecules and alkyl halides is being investigated in more detail. Current attention is given to defining the nature of the enhancement yields in the condensed phase. Specifically, energetic halogen reactions in liquid and frozen aqueous solutions or organic and biomolecular solutes are studied. (3) Reactions of bromine and iodine activated by isomeric transition with halogenated biomolecular and organic solutes in liquid and frozen aqueous solutions are being studied in an attempt to learn more about the activation events in the condensed phase. (4) The applications of hot chemistry techniques and theory to neutron activation analysis of biological systems are being continued. Current attention is given to developing procedures for trace molecular determinations in biological systems. The applications of hot halogen atoms as site indicators in liquid and frozen aqueous solutions of halogenated bases and nucleosides are currently being developed. 14 references

Facile synthesis of polyaniline nanotubes using reactive oxide templates for high energy density pseudocapacitors

KAUST Repository

Chen, Wei

2013-01-01

A remarkable energy density of 84 W h kg(cell) -1 and a power density of 182 kW kg(cell) -1 have been achieved for full-cell pseudocapacitors using conducting polymer nanotubes (polyaniline) as electrode materials and ionic liquid as electrolytes. The polyaniline nanotubes were synthesized by a one-step in situ chemical polymerization process utilizing MnO2 nanotubes as sacrificial templates. The polyaniline-nanotube pseudocapacitors exhibit much better electrochemical performance than the polyaniline-nanofiber pseudocapacitors in both acidic aqueous and ionic liquid electrolytes. Importantly, the incorporation of ionic liquid with polyaniline-nanotubes has drastically improved the energy storage capacity of the PAni-nanotube pseudocapacitors by a factor of ∼5 times compared to that of the PAni-nanotube pseudocapacitors in the acidic aqueous electrolyte. Furthermore, even after 10000 cycles, the PAni-nanotube pseudocapacitors in the ionic liquid electrolyte maintain sufficient high energy density and can light LEDs for several minutes, with only 30 s quick charge. © 2013 The Royal Society of Chemistry.

Solid state chemistry and its applications

CERN Document Server

West, Anthony R

2013-01-01

Solid State Chemistry and its Applications, 2nd Edition: Student Edition is an extensive update and sequel to the bestselling textbook Basic Solid State Chemistry, the classic text for undergraduate teaching in solid state chemistry worldwide. Solid state chemistry lies at the heart of many significant scientific advances from recent decades, including the discovery of high-temperature superconductors, new forms of carbon and countless other developments in the synthesis, characterisation and applications of inorganic materials. Looking forward, solid state chemistry will be crucial for the

Frontiers in Atmospheric Chemistry Modelling

Science.gov (United States)

Colette, Augustin; Bessagnet, Bertrand; Meleux, Frederik; Rouïl, Laurence

2013-04-01

The first pan-European kilometre-scale atmospheric chemistry simulation is introduced. The continental-scale air pollution episode of January 2009 is modelled with the CHIMERE offline chemistry-transport model with a massive grid of 2 million horizontal points, performed on 2000 CPU of a high performance computing system hosted by the Research and Technology Computing Center at the French Alternative Energies and Atomic Energy Commission (CCRT/CEA). Besides the technical challenge, which demonstrated the robustness of the selected air quality model, we discuss the added value in terms of air pollution modelling and decision support. The comparison with in-situ observations shows that model biases are significantly improved despite some spurious added spatial variability attributed to shortcomings in the emission downscaling process and coarse resolution of the meteorological fields. The increased spatial resolution is clearly beneficial for the detection of exceedances and exposure modelling. We reveal small scale air pollution patterns that highlight the contribution of city plumes to background air pollution levels. Up to a factor 5 underestimation of the fraction of population exposed to detrimental levels of pollution can be obtained with a coarse simulation if subgrid scale correction such as urban increments are ignored. This experiment opens new perspectives for environmental decision making. After two decades of efforts to reduce air pollutant emissions across Europe, the challenge is now to find the optimal trade-off between national and local air quality management strategies. While the first approach is based on sectoral strategies and energy policies, the later builds upon new alternatives such as urban development. The strategies, the decision pathways and the involvement of individual citizen differ, and a compromise based on cost and efficiency must be found. We illustrated how high performance computing in atmospheric science can contribute to this

Dietary patterns of obese high school girls: snack consumption and energy intake

OpenAIRE

Yoon, Jin-Sook; Lee, Nan-Jo

2010-01-01

In order to develop an obesity management program for teenagers, we compared obese and non-obese girls attending high schools in terms of their dietary practices related to snack consumption. Dietary records were collected for 7 days. No significant differences were found for the average daily energy intake between obese and non-obese girls. However, the highest energy intake was greater for obese girls while not much difference was found for the lowest amount of energy intake. Obese girls ha...

Characterisation of the inorganic chemistry of surface waters in ...

African Journals Online (AJOL)

The main purpose of this study was to determine a simple inorganic chemistry index that can be used for all surface waters in South Africa, in order to characterise the inorganic chemistry of surface waters. Water quality data collected up until 1999 from all sample monitoring stations (2 068 monitoring stations, 364 659 ...

Institute for Sustainable Energy

Energy Technology Data Exchange (ETDEWEB)

Agrawal, Ajay [Univ. of Alabama, Tuscaloosa, AL (United States)

2016-03-28

Alternate fuels offer unique challenges and opportunities as energy source for power generation, vehicular transportation, and industrial applications. Institute for Sustainable Energy (ISE) at UA conducts innovative research to utilize the complex mix of domestically-produced alternate fuels to achieve low-emissions, high energy-efficiency, and fuel-flexibility. ISE also provides educational and advancement opportunities to students and researchers in the energy field. Basic research probing the physics and chemistry of alternative fuels has generated practical concepts investigated in a burner and engine test platforms.

Collective space of high-rise housing complex

Directory of Open Access Journals (Sweden)

Bakaeva Tatyana

2018-01-01

Full Text Available The article considers the problems of support of citizens a comfortable living environment in the conditions of the limited territory of the megalopolis, the typological principles of formation of space-planning structure high-rise residence complexes with public space. The collective space for residents of high-rise housing estates on the example of international experience of design and construction is in detail considered. The collective space and the area of the standard apartment are analysed on comfort classes: a social - complex Pinnacle @ Duxton, a business - Monde Condos and an elite - Hamilton Scotts. Interdependence the area of the standard flat and the total area of housing collective space, in addiction on the comfort level, is revealed. In the conditions of high-density urban development, the collective space allows to form the comfortable environment for accommodation. The recommendations for achievement of integrity and improvement of quality of the city environment are made. The convenient collective space makes a contribution to civil policy, it creates the socializing sense of interaction of residents, coagulates social effect.

Collective space of high-rise housing complex

Science.gov (United States)

Bakaeva, Tatyana

2018-03-01

The article considers the problems of support of citizens a comfortable living environment in the conditions of the limited territory of the megalopolis, the typological principles of formation of space-planning structure high-rise residence complexes with public space. The collective space for residents of high-rise housing estates on the example of international experience of design and construction is in detail considered. The collective space and the area of the standard apartment are analysed on comfort classes: a social - complex Pinnacle @ Duxton, a business - Monde Condos and an elite - Hamilton Scotts. Interdependence the area of the standard flat and the total area of housing collective space, in addiction on the comfort level, is revealed. In the conditions of high-density urban development, the collective space allows to form the comfortable environment for accommodation. The recommendations for achievement of integrity and improvement of quality of the city environment are made. The convenient collective space makes a contribution to civil policy, it creates the socializing sense of interaction of residents, coagulates social effect.

Grid Computing in High Energy Physics

International Nuclear Information System (INIS)

Avery, Paul

2004-01-01

Over the next two decades, major high energy physics (HEP) experiments, particularly at the Large Hadron Collider, will face unprecedented challenges to achieving their scientific potential. These challenges arise primarily from the rapidly increasing size and complexity of HEP datasets that will be collected and the enormous computational, storage and networking resources that will be deployed by global collaborations in order to process, distribute and analyze them.Coupling such vast information technology resources to globally distributed collaborations of several thousand physicists requires extremely capable computing infrastructures supporting several key areas: (1) computing (providing sufficient computational and storage resources for all processing, simulation and analysis tasks undertaken by the collaborations); (2) networking (deploying high speed networks to transport data quickly between institutions around the world); (3) software (supporting simple and transparent access to data and software resources, regardless of location); (4) collaboration (providing tools that allow members full and fair access to all collaboration resources and enable distributed teams to work effectively, irrespective of location); and (5) education, training and outreach (providing resources and mechanisms for training students and for communicating important information to the public).It is believed that computing infrastructures based on Data Grids and optical networks can meet these challenges and can offer data intensive enterprises in high energy physics and elsewhere a comprehensive, scalable framework for collaboration and resource sharing. A number of Data Grid projects have been underway since 1999. Interestingly, the most exciting and far ranging of these projects are led by collaborations of high energy physicists, computer scientists and scientists from other disciplines in support of experiments with massive, near-term data needs. I review progress in this

Scientific projection paper for radiation chemistry

International Nuclear Information System (INIS)

Powers, E.L.

1980-01-01

Among all the environmental hazards to which man is exposed, ionizing radiation is the most thoroughly investigated and the most responsibly monitored and controlled. Nevertheless, because of the importance of radiation in modern society from both the hazard as well as the utilitarian standpoints, much more information concerning the biological effects induced and their modification and reversal is required. Together with radiation physics, an understanding of radiation chemistry is necessary for full appreciation of biological effects of high and low energy radiations, and for the development of prophylactic, therapeutic and potentiating methods and techniques in biological organisms

Chemistry in high temperature aqueous solutions application to the power industry

International Nuclear Information System (INIS)

Cohen, P.

1990-01-01

The power industry utilizes water (aqueous solutions) for two main functions: as a medium for heat transfer and transport and as a thermodynamic working fluid. These functions are performed in systems fabricated from a wide variety of materials, over a wide range of thermal and hydraulic conditions, and at medium temperatures and densities which determine the significant chemical properties. The major chemical interest is in the concentrated solutions derived from the dilute working fluid at selected sites defined by the physical arrangement and temperature and in their consequential effects on heat transfer and corrosion. Examples of these sites for typical fossil fired and nuclear steam generating equipment are described, as well as the extent and limit of the concentration process. The history of steam power plant water chemistry is discussed from the point of view of the chemical processes involved. The period covered is from the 1920s to the present state of the art, which is a major application of the subject of this symposium--chemistry in high temperature aqueous solution

Computational chemistry

Science.gov (United States)

Arnold, J. O.

1987-01-01

With the advent of supercomputers, modern computational chemistry algorithms and codes, a powerful tool was created to help fill NASA's continuing need for information on the properties of matter in hostile or unusual environments. Computational resources provided under the National Aerodynamics Simulator (NAS) program were a cornerstone for recent advancements in this field. Properties of gases, materials, and their interactions can be determined from solutions of the governing equations. In the case of gases, for example, radiative transition probabilites per particle, bond-dissociation energies, and rates of simple chemical reactions can be determined computationally as reliably as from experiment. The data are proving to be quite valuable in providing inputs to real-gas flow simulation codes used to compute aerothermodynamic loads on NASA's aeroassist orbital transfer vehicles and a host of problems related to the National Aerospace Plane Program. Although more approximate, similar solutions can be obtained for ensembles of atoms simulating small particles of materials with and without the presence of gases. Computational chemistry has application in studying catalysis, properties of polymers, all of interest to various NASA missions, including those previously mentioned. In addition to discussing these applications of computational chemistry within NASA, the governing equations and the need for supercomputers for their solution is outlined.

Radiation chemistry in nuclear technology

International Nuclear Information System (INIS)

Katsumura, Yosuke

2006-01-01

The importance of radiation chemistry in the field of nuclear technology including reactor chemistry, spent fuel reprocessing and radioactive high level waste repository, is summarized and, in parallel, our research activity will be briefly presented. (author)

Some aspects of the organic, biological and inorganic chemistry of astatine

International Nuclear Information System (INIS)

Visser, G.W.M.

1982-01-01

Astatine has no stable isotopes and the radioactive isotopes with half-lives sufficiently long for chemical experiments ( 209 At, 210 At, 211 At) must be produced artificially with a cyclotron or with a high energy accelerator by spallation of Th. This thesis deals with the synthesis and chemistry of At-compounds and the determination of some of their properties. (C.F.)

Improving chemistry performance in CANDU plants

International Nuclear Information System (INIS)

Turner, C.; Guzonas, D.

2010-01-01

There is a strong interplay between coolant chemistry and materials selection in any nuclear power plant system. To achieve the design life of reactor components it is necessary to monitor and control relevant chemistry parameters, such as ionic conductivity, pH, concentrations of dissolved ions and redox species (e.g., hydrogen, hydrazine, oxygen) and the concentrations of suspended corrosion products. Chemistry specifications are set to achieve a balance between the sometimes conflicting requirements to minimize corrosion and radiological dose and to minimize operating and maintenance costs over the lifetime of the plant. For the past decade, Atomic Energy of Canada Limited (AECL) has taken a rigorous and disciplined approach to reviewing and updating all aspects of chemistry control in the CANDU® nuclear power plant (NPP). This approach has included proactively reviewing chemistry operating experience from existing CANDU® and other water-cooled NPPs worldwide to identify and address emerging issues, updating all of our chemistry control documentation to ensure that each chemistry parameter is linked to a specific requirement (e.g., reduce activity transport, monitor for condenser leak) and incorporating the latest results from our Research and Development (R and D) programs to ensure that all chemistry specifications are supported by a sound rationale. The results of this review and update have been incorporated into updated chemistry specifications and, in some cases, modified operating procedures for new and existing plants. In addition, recommendations have been made for design modifications to improve chemistry control in new build plants, especially during periods of shutdown and startup when chemistry control has traditionally been more challenging. Chemistry control in new-build CANDU® plants will rely increasingly on the use of on-line instrumentation interfaced directly to AECL's state-of-the-art chemistry monitoring, diagnostics and analysis

High-energy test of proton radiography concepts

International Nuclear Information System (INIS)

Amann, J.F.; Atencio, L.G.; Espinoza, C.J.

1997-01-01

This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goal of this work was to demonstrate the use of high energy protons to produce radiographs of heavy metal test objects. The authors executed a proof-of-principle experiment using GeV proton beams available at the Brookhaven National Laboratory Alternating Gradient Synchrotron (AGS). The experiment produced proton radiographs of a suitably dense, unclassified test object. The experiment tested capabilities in data collection, image reconstruction, and hydro-code simulation and validated models of high-energy proton radiography. A lens was designed using existing quadrupole magnets, constructed on the A1 beam line of the AGS and used to image 10-GeV protons. The results include: (1) images made with an integrating detector, (2) measurements of the background and measurements of the resolution functions, and (3) forward model fits to the transmission data. In all cases the results agree with initial estimates and provide strong support for the utility of proton radiography as a new hydrotest diagnostic

NCAW feed chemistry: Effect of starting chemistry on melter offgas and iron redox

International Nuclear Information System (INIS)

Smith, P.A.; Vienna, J.D.; Merz, M.D.

1995-03-01

The Pacific Northwest Laboratory (PNL) Vitrification Technology Development (PVTD) program has been established to develop technology to support immobilization of selected Hanford wastes. The effort of the PVTD program is directed by the U.S. Department of Energy (DOE). This report is part of the effort and focuses on the effect of starting waste chemistry on the vitrification process. The objective of the investigation was the evaluation of the effect of starting chemistry on the cold cap behavior in the vitrification of simulated neutralized current acid waste (NCAW). In addition this investigation provides an initial laboratory investigation of the cold cap and method for evaluation of alternate reductants

Nuclear chemistry and Radiochemistry in the USA

International Nuclear Information System (INIS)

Kronenberg, A.

2004-01-01

Nuclear chemistry and radiochemistry are very young sciences which developed at an extremely brisk pace within a very short period of time after the discovery of nuclear fission in 1938, and caused profound societal changes. In the United States, nuclear chemistry developed very differently from Germany, where nuclear research initially had been banned after the Second World War. The prime mover in the development in the United States was the Manhattan Project, the construction of the atomic bomb. The counteract the impending shortage of qualified personnel, important institutions have begun to establish training and support programs in the field. The National Laboratories in the United States introduced a National Security Internship Program, while the U.S. Department of Energy (DOE) tries to promote cooperation, and thus the training of personnel, by launching programs of its own. Yet, a greater shortage of qualified personnel is becoming apparent. The situation of nuclear chemistry and radiochemistry in the United States can be summarized in the finding that research at the National Laboratories is very wide ranging. It receives sufficient funds from the DOE. However, the National Laboratories show a very high proportion of elderly personnel, a problem which will have to be corrected in the years to come. This may be helped by the Summer Schools financed by the DOE, though a summer school of six weeks cannot replace a sound training in nuclear chemistry of the kind still to be found in Germany. (orig.) [de

Structure and chemistry of epitaxial ceria thin films on yttria-stabilized zirconia substrates, studied by high resolution electron microscopy

Energy Technology Data Exchange (ETDEWEB)

Sinclair, Robert, E-mail: bobsinc@stanford.edu [Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305 (United States); Lee, Sang Chul, E-mail: sclee99@stanford.edu [Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305 (United States); Shi, Yezhou; Chueh, William C. [Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305 (United States); Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States); Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States)

2017-05-15

We have applied aberration-corrected transmission electron microscopy (TEM) imaging and electron energy loss spectroscopy (EELS) to study the structure and chemistry of epitaxial ceria thin films, grown by pulsed laser deposition onto (001) yttria-stabilized zirconia (YSZ) substrates. There are few observable defects apart from the expected mismatch interfacial dislocations and so the films would be expected to have good potential for applications. Under high electron beam dose rate (above about 6000 e{sup -}/Å{sup 2}s) domains of an ordered structure appear and these are interpreted as being created by oxygen vacancy ordering. The ordered structure does not appear at lower lose rates (ca. 2600 e{sup -}/Å{sup 2}s) and can be removed by imaging under 1 mbar oxygen gas in an environmental TEM. EELS confirms that there is both oxygen deficiency and the associated increase in Ce{sup 3+} versus Ce{sup 4+} cations in the ordered domains. In situ high resolution TEM recordings show the formation of the ordered domains as well as atomic migration along the ceria thin film (001) surface. - Highlights: • The local structure and chemistry of ceria can be studied by TEM combined with EELS. • At lower electron, there are no observable changes in the ceria thin films. • At higher dose rates, an ordered phase is created due to oxygen vacancy ordering. • In situ HRTEM shows the oxygen vacancy ordering and the movement of surface atoms.

The separate and collective effects of personalization, personification, and gender on learning with multimedia chemistry instructional materials

Science.gov (United States)

Halkyard, Shannon

Chemistry is a difficult subject to learn and teach for students in general. Additionally, female students are under-represented in chemistry and the physical sciences. Within chemistry, atomic and electronic structure is a key concept and several recommendations in the literature describe how this topic can be taught better. These recommendations can be employed in multimedia instructional materials designed following principles understood through the Cognitive Theory of Multimedia Learning. Additionally, these materials can expand the known use of principles like personalization (addressing the learner as "you") and test prospective design principles like personification (referring to abstract objects like atoms as "she" or "he"). The purpose of this study was to use the recommendations on teaching atomic and electronic structure along with known multimedia design principles to create multimedia chemistry learning materials that can be used to test the use of personalization and personification both separately and together. The study also investigated how learning with these materials might be different for male and female students. A sample of 329 students from private northern California high schools were given an atomic structure pre-test, watched a multimedia chemistry instructional video, and took a post-test on atomic structure. Students were randomly assigned to watch one of six versions of the instructional video. Students in the six groups were compared using ANOVA procedures and no significant differences were found. Males were compared to females for the six different treatment conditions and the most significant difference was for the treatment that combined personalization (you) and female personification (she), with a medium effect size (Cohen's d=0.65). Males and females were then compared separately across the six groups using ANOVA procedures and t-tests. A significant difference was found for female students using the treatment that combined

Radial collective flow in heavy-ion collisions at intermediate energies

International Nuclear Information System (INIS)

Borderie, B.

1996-11-01

The production of radial collective flow is associated with collisions leading to sources which undergo multifragmentation/explosion processes. After a theoretical survey of possible causes of production of radial flow, methods used to derive experimental values are discussed. Finally, a large set of data is presented which can be used to study and disentangle the different effects leading to radial collective flow. The dominant role of compression in the lower energy domain is emphasized. (author)

Physics and chemistry of niobium materials in the context of superconducting RF cavity applications

International Nuclear Information System (INIS)

Roy, S.B.

2016-01-01

Superconducting radio frequency (SCRF) cavities excel over the normal conducting RF cavities in the long pulse or continuous wave high energy particle accelerations, and niobium (Nb) is currently the material of choice for fabrication of such SCRF cavities. However the accelerating gradients attained in the Nb SCRF cavities deployed in various high energy particle accelerators are significantly below the theoretical limit predicted by the superconducting properties of Nb. Thus it is very important to understand the physics and chemistry of Nb materials in some details so as to maximize the SCRF cavity performance. This abstract will discuss some issues which help in the development of high gradient and energy efficient Nb SCRF cavities in a cost effective manner. (author)

Hydroxyl and Hydroperoxy Radical Chemistry during the MCMA-2006 Field Campaign: Measurement and Model Comparison

Science.gov (United States)

Dusanter, S.; Vimal, D.; Stevens, P. S.; Volkamer, R.; Molina, L. T.

2007-12-01

The Mexico City Metropolitan Area (MCMA) field campaign, held in March 2006, was a unique opportunity to collect data in one of the most polluted megacities in the world. Such environments exhibit a complex oxidation chemistry involving a strong coupling between odd hydrogen radicals (HOX=OH+HO2) and nitrogen oxides species (NOX=NO+NO2). High levels of volatile organic compounds (VOCs) and NOX control the HOX budget and lead to elevated tropospheric ozone formation. The HOX-NOX coupling can be investigated by comparing measured and model-predicted HOx concentrations. Atmospheric HOX concentrations were measured by the Indiana University laser-induced fluorescence instrument and data were collected at the Instituto Mexicano del Petroleo between 14 and 31 March. Measured hydroxyl radical (OH) concentrations are comparable to that measured in less polluted urban environments and suggest that the OH concentrations are highly buffered under high NOX conditions. In contrast, hydroperoxy radical (HO2) concentrations are more sensitive to the NOX levels and are highly variable between different urban sites. Enhanced levels of OH and HO2 radicals were observed on several days between 9h30-11h00 AM and suggest an additional HOX source for the morning hours and/or a fast HOX cycling under the high NOX conditions of the MCMA. A preliminary investigation of the HOX chemistry occurring in the MCMA urban atmosphere was performed using a photochemical box model based on the Regional Atmospheric Chemistry Mechanism (RACM). Model comparisons will be presented and the agreement between measured and predicted HOX concentrations will be discussed.

Grid computing in high energy physics

CERN Document Server

Avery, P

2004-01-01

Over the next two decades, major high energy physics (HEP) experiments, particularly at the Large Hadron Collider, will face unprecedented challenges to achieving their scientific potential. These challenges arise primarily from the rapidly increasing size and complexity of HEP datasets that will be collected and the enormous computational, storage and networking resources that will be deployed by global collaborations in order to process, distribute and analyze them. Coupling such vast information technology resources to globally distributed collaborations of several thousand physicists requires extremely capable computing infrastructures supporting several key areas: (1) computing (providing sufficient computational and storage resources for all processing, simulation and analysis tasks undertaken by the collaborations); (2) networking (deploying high speed networks to transport data quickly between institutions around the world); (3) software (supporting simple and transparent access to data and software r...

Marcoule institute for separation chemistry - ICSM. Scientific report 2007 - 2010