WorldWideScience

Sample records for level surface science

  1. Towards an atomic level understanding of niobia based catalysts and catalysis by combining the science of catalysis with surface science

    Directory of Open Access Journals (Sweden)

    Martin Schmal

    2009-06-01

    Full Text Available The science of catalysis and surface science have developed, independently, key information for understanding catalytic processes. One might argue: is there anything fundamental to be discovered through the interplay between catalysis and surface science? Real catalysts of monometallic and bimetallic Co/Nb2O5 and Pd-Co/Nb2O5 catalysts showed interesting selectivity results on the Fischer-Tropsch synthesis (Noronha et al. 1996, Rosenir et al. 1993. The presence of a noble metal increased the C+5 selectivity and decreased the methane formation depending of the reduction temperature. Model catalyst of Co-Pd supported on niobia and alumina were prepared and characterized at the atomic level, thus forming the basis for a comparison with "real" support materials. Growth, morphology and structure of both pure metal and alloy particles were studied. It is possible to support the strong metal support interaction suggested by studies on real catalysts via the investigation of model systems for niobia in comparison to alumina support in which this effect does not occur. Formation of Co2+ penetration into the niobia lattice was suggested on the basis of powder studies and can be fully supported on the basis of model studies. It is shown for both real catalysts and model systems that oxidation state of Co plays a key role in controlling the reactivity in Fischer-Tropsch reactions systems and that the addition of Pd is a determining factor for the stability of the catalyst. It is demonstrated that the interaction with unsaturated hydrocarbons depends strongly on the state of oxidation.As ciências da catálise e da superfície têm desenvolvido independentemente temas básicos para o entendimento de processos catalíticos. Pode-se até questionar se há ainda algo fundamental para ser descoberto através da interface entre catálise eciência da superfície? Catalisadores mono e bimetálicos de Co/Nb2O5 e Pd-Co/ Nb2O5 apresentaram resultados interessantes de

  2. Interfacial and Surface Science | Materials Science | NREL

    Science.gov (United States)

    Science group within the Material Science Center. He oversees research studies of surfaces and interfaces Interfacial and Surface Science Interfacial and Surface Science Image of irregular-outlined, light address a broad range of fundamental and applied issues in surface and interfacial science that are

  3. Biomaterials surface science

    CERN Document Server

    Taubert, Andreas; Rodriguez-Cabello, José Carlos

    2013-01-01

    The book provides an overview of the highly interdisciplinary field of surface science in the context of biological and biomedical applications. The covered topics range from micro- and nanostructuring for imparting functionality in a top-down manner to the bottom-up fabrication of gradient surfaces by self-assembly, from interfaces between biomaterials and living matter to smart, stimuli-responsive surfaces, and from cell and surface mechanics to the elucidation of cell-chip interactions in biomedical devices.

  4. Surface science and catalysis

    International Nuclear Information System (INIS)

    Somorjai, G.A.

    1985-02-01

    Modern surface science studies have explored a large number of metal catalyst systems. Three classes of catalytic reactions can be identified: (1) those that occur over the metal surface; (2) reactions that take place on top of a strongly adsorbed overlayer and (3) reactions that occur on co-adsorbate modified surfaces. Case histories for each class are presented. 44 refs., 13 figs., 3 tabs

  5. Surface science an introduction

    CERN Document Server

    Hudson, John

    1991-01-01

    The whole field of surface science is covered in this work. Starting with a description of the structure and thermodynamics of clean surfaces, the book goes on to discuss kinetic theory of gases and molecular beam formation. This is followed by a largesection on gas-surface interactions, and another major section on energetic particle-surface interactions. The final chapter provides the background to crystal nucleation and growth. The approach adopted is interdisciplinary and slanted towards theexperimental side, with practical analytical techniques being used to illustrate general princi

  6. Surface science techniques

    CERN Document Server

    Walls, JM

    2013-01-01

    This volume provides a comprehensive and up to the minute review of the techniques used to determine the nature and composition of surfaces. Originally published as a special issue of the Pergamon journal Vacuum, it comprises a carefully edited collection of chapters written by specialists in each of the techniques and includes coverage of the electron and ion spectroscopies, as well as the atom-imaging methods such as the atom probe field ion microscope and the scanning tunnelling microscope. Surface science is an important area of study since the outermost surface layers play a crucial role

  7. Surface science techniques

    CERN Document Server

    Bracco, Gianangelo

    2013-01-01

    The book describes the experimental techniques employed to study surfaces and interfaces. The emphasis is on the experimental method. Therefore all chapters start with an introduction of the scientific problem, the theory necessary to understand how the technique works and how to understand the results. Descriptions of real experimental setups, experimental results at different systems are given to show both the strength and the limits of the technique. In a final part the new developments and possible extensions of the techniques are presented. The included techniques provide microscopic as well as macroscopic information. They cover most of the techniques used in surface science.

  8. Science Curriculum Guide, Level 4.

    Science.gov (United States)

    Newark School District, DE.

    The fourth of four levels in a K-12 science curriculum is outlined. In Level 4 (grades 9-12), science areas include earth science, biology, chemistry, and physics. Six major themes provide the basis for study in all levels (K-12). These are: Change, Continuity, Diversity, Interaction, Limitation, and Organization. In Level 4, all six themes are…

  9. Solvay Conference on Surface Science

    CERN Document Server

    1988-01-01

    The articles collected in this volume give a broad overview of the current state of surface science. Pioneers in the field and researchers met together at this Solvay Conference to discuss important new developments in surface science, with an emphasis on the common area between solid state physics and physical chemistry. The contributions deal with the following subjects: structure of surfaces, surface science and catalysis, two-dimensional physics and phase transitions, scanning tunneling microscopy, surface scattering and surface dynamics, chemical reactions at surfaces, solid-solid interfaces and superlattices, and surface studies with synchrotron radiation. On each of these subjects an introductory review talk and a number of short research contributions are followed by extensive discussions, which appear in full in the text. This nineteenth Solvay Conference commemorates the 75th anniversary of the Solvay Institutes.

  10. Surface science and heterogeneous catalysis

    International Nuclear Information System (INIS)

    Somorjai, G.A.

    1980-05-01

    The catalytic reactions studied include hydrocarbon conversion over platinum, the transition metal-catalyzed hydrogenation of carbon monoxide, and the photocatalyzed dissociation of water over oxide surfaces. The method of combined surface science and catalytic studies is similar to those used in synthetic organic chemistry. The single-crystal models for the working catalyst are compared with real catalysts by comparing the rates of cyclopropane ring opening on platinum and the hydrogenation of carbon monoxide on rhodium single crystal surface with those on practical commercial catalyst systems. Excellent agreement was obtained for these reactions. This document reviews what was learned about heterogeneous catalysis from these surface science approaches over the past 15 years and present models of the active catalyst surface

  11. The surface science of enzymes

    DEFF Research Database (Denmark)

    Rod, Thomas Holm; Nørskov, Jens Kehlet

    2002-01-01

    One of the largest challenges to science in the coming years is to find the relation between enzyme structure and function. Can we predict which reactions an enzyme catalyzes from knowledge of its structure-or from its amino acid sequence? Can we use that knowledge to modify enzyme function......? To solve these problems we must understand in some detail how enzymes interact with reactants from its surroundings. These interactions take place at the surface of the enzyme and the question of enzyme function can be viewed as the surface science of enzymes. In this article we discuss how to describe...... catalysis by enzymes, and in particular the analogies between enzyme catalyzed reactions and surface catalyzed reactions. We do this by discussing two concrete examples of reactions catalyzed both in nature (by enzymes) and in industrial reactors (by inorganic materials), and show that although analogies...

  12. Modern techniques of surface science

    CERN Document Server

    Woodruff, D Phil

    2016-01-01

    This fully revised, updated and reorganised third edition provides a thorough introduction to the characterisation techniques used in surface science and nanoscience today. Each chapter brings together and compares the different techniques used to address a particular research question, including how to determine the surface composition, surface structure, surface electronic structure, surface microstructure at different length scales (down to sub-molecular), and the molecular character of adsorbates and their adsorption or reaction properties. Readers will easily understand the relative strengths and limitations of the techniques available to them and, ultimately, will be able to select the most suitable techniques for their own particular research purposes. This is an essential resource for researchers and practitioners performing materials analysis, and for senior undergraduate students looking to gain a clear understanding of the underlying principles and applications of the different characterisation tec...

  13. How old is surface science?

    International Nuclear Information System (INIS)

    Paparazzo, E.

    2004-01-01

    Philosophical and literary testimonies from the Classical World (5th century B.C. to 3rd century A.D.) involving solid surfaces are reviewed. Plato thought the surface to be a real entity, whereas Aristotle considered it to possess an unqualified existence, i.e. not to be a substance, but just an accidental entity. The Old Stoics asserted that surfaces do not possess any physical existence, although the Stoic philosopher Posidonius--apparently the only exception in his school--held them to exist both in thought and reality. While both the Atomists and the Epicureans were very little interested in them, the Sceptic philosopher Sextus Empiricus considered surfaces to be the limits of a body, although he maintained that both the view that they are corporeal or the view that they are incorporeal present unsurmountable difficulties. Among Roman authors, the testimony from Pliny the Elder is mostly concerned with metallic surfaces, chemical change occurring there, and surface treatments used in antiquity. Besides the philosophical motivations, the implications of the testimonies are discussed in the light of surface science. The purely geometrical surface of Plato is found to compare favorably to single-crystal surface, Posidonius' 'corporeal' surface is best likened to an air-oxidized, or otherwise ambient-modified surface, and ancient accounts on mixture are compared to XPS results obtained in adhesion studies of enameled steels. I argue that the long-standing dominance of Aristotle's view from antiquity onwards may have had a part in delaying theoretical speculation into solid surfaces

  14. Practical guide to surface science and spectroscopy

    CERN Document Server

    Chung, Yip-Wah

    2001-01-01

    Practical Guide to Surface Science and Spectroscopy provides a practical introduction to surface science as well as describes the basic analytical techniques that researchers use to understand what occurs at the surfaces of materials and at their interfaces. These techniques include auger electron spectroscopy, photoelectron spectroscopy, inelastic scattering of electrons and ions, low energy electron diffraction, scanning probe microscopy, and interfacial segregation. Understanding the behavior of materials at their surfaces is essential for materials scientists and engineers as they design and fabricate microelectronics and semiconductor devices. The book gives over 100 examples, discussion questions and problems with varying levels of difficulty. Included with this book is a CD-ROM, which not only contains the same information, but also provides many elements of animation and interaction that are not easily emulated on paper. In diverse subject matters ranging from the operation of ion pumps, computer-...

  15. Progress in surface and membrane science

    CERN Document Server

    Danielli, J F; Cadenhead, D A

    1973-01-01

    Progress in Surface and Membrane Science, Volume 6 covers the developments in the study of surface and membrane science. The book discusses the progress in surface and membrane science; the solid state chemistry of the silver halide surface; and the experimental and theoretical aspects of the double layer at the mercury-solution interface. The text also describes contact-angle hysteresis; ion binding and ion transport produced by neutral lipid-soluble molecules; and the biophysical interactions of blood proteins with polymeric and artificial surfaces. Physical chemists, biophysicists, and phys

  16. Progress in surface and membrane science

    CERN Document Server

    Cadenhead, D A

    1977-01-01

    Progress in Surface and Membrane Science, Volume 11 covers the advances in the study of surface and membrane science. The book discusses the quantum theory of surface phenomena; some fundamental aspects of electrocrystallization; and exoelectric emission. The text also describes the surface of titanium dioxide; and the prospects for atomic resolution electron microscopy in membranology. Chemists, physicists, and people involved in the electrochemical power laboratory will find the book useful.

  17. Surface Science Foundations of Catalysis and Nanoscience

    CERN Document Server

    Kolasinski, Kurt K

    2012-01-01

    Surface science has evolved beyond being a sub-field of chemistry or physics and has now become an underpinning science. The Third Edition of this book incorporates extensive worked solutions, as well as details on how problem solving relevant to surface science should be performed. It contextualizes the exercises and their solutions to further explicate the methods of problem solving, application of scientific principles and to deliver a deeper understanding of the field of surface science. Solutions will be accompanied by figures and/or graphs of data, as appropriate.

  18. Surface Science Foundations of Catalysis and Nanoscience

    CERN Document Server

    Kolasinski, Kurt K

    2012-01-01

    Surface science has evolved from being a sub-field of chemistry or physics, and has now established itself as an interdisciplinary topic. Knowledge has developed sufficiently that we can now understand catalysis from a surface science perspective. No-where is the underpinning nature of surface science better illustrated than with nanoscience. Now in its third edition, this successful textbook aims to provide students with an understanding of chemical transformations and the formation of structures at surfaces. The chapters build from simple to more advanced principles with each featuring exerc

  19. Progress in surface and membrane science

    CERN Document Server

    Danielli, J F; Cadenhead, D A

    1972-01-01

    Progress in Surface and Membrane Science, Volume 5 covers the developments in the study of surface and membrane science. The book discusses the Mössbauer effect in surface science; the surface functional groups on carbon and silica; and the wetting phenomena pertaining to adhesion. The text also describes the physical state of phospholipids and cholesterol in monolayers, bilayers, and membranes; the characteristics of heterocoagulation; and the effects of calcium on excitable membranes and neurotransmitter action. Chemists, physiologists, biophysicists, and civil engineers will find the book i

  20. Progress in surface and membrane science

    CERN Document Server

    Cadenhead, D A

    1979-01-01

    Progress in Surface and Membrane Science, Volume 12 covers the advances in the study of surface and membrane science. The book discusses the topographical differentiation of the cell surface; the NMR studies of model biological membrane system; and an irreversible thermodynamic approach to energy coupling in mitochondria and chloroplasts. The text also describes water at surfaces; the nature of microemulsions; and the energy principle in the stability of interfaces. Biochemists, physicists, chemical engineers, and people involved in surface and coatings research will find the book invaluable.

  1. Progress in surface and membrane science

    CERN Document Server

    Danielli, J F; Cadenhead, D A

    1971-01-01

    Progress in Surface and Membrane Science, Volume 4 covers the developments in the study of surface and membrane science. The book discusses waves at interfaces; recent investigations on the thickness of surface layers; and surface analysis by low-energy electron diffraction and Auger electron spectroscopy. The text also describes the anode electrolyte interface; the interactions of adsorbed proteins and polypeptides at interfaces; and peptide-induced ion transport in synthetic and biological membranes. The monolayer adsorption on crystalline surfaces is also considered. Chemists and metallurgi

  2. Progress in surface and membrane science

    CERN Document Server

    Cadenhead, D A; Rosenberg, M D

    1974-01-01

    Progress in Surface and Membrane Science, Volume 8 covers the developments in the study of surface and membrane science. The book discusses the applications of statistical mechanics to physical adsorption; the impact of electron spectroscopy and cognate techniques on the study of solid surfaces; and the ellipsometric studies of thin films. The text also describes the interfacial photochemistry of bilayer lipid membranes; cell junctions and their development; and the composition and function of the inner mitochondrial membrane. The role of the cell surface in contact inhibition of cell division

  3. Recent progress in surface science v.2

    CERN Document Server

    Danielli, J F; Riddiford, A C

    1964-01-01

    Recent Progress in Surface Science, Volume 2 is a 10-chapter text that covers the significant advances in some aspects of surface science, including in catalysis, genetic control of cell surface, and cell membrane. The opening chapter deals with the major factors affecting adsorption at the gas-solid interface. The subsequent chapters explore the advances in understanding of heterogeneous catalysis in terms of fundamental surface processes, as well as the concept of dynamic contact angles. These topics are followed by discussions on emulsions, flotation, and the extraordinary complexity of cel

  4. Current trends of surface science and catalysis

    CERN Document Server

    Park, Jeong Young

    2014-01-01

    Including detail on applying surface science in renewable energy conversion, this book covers the latest results on model catalysts including single crystals, bridging "materials and pressure gaps", and hot electron flows in heterogeneous catalysis.

  5. Report of the surface science workshop

    International Nuclear Information System (INIS)

    Somorjai, G.A.; Yates, J.T. Jr.; Clinton, W.

    1977-03-01

    A three-day workshop was held to review the various areas of energy development and technology in which surface science plays major roles and makes major contributions, and to identify the major surface-science-related problem areas in the fields with ERDA's mission in the fossil, nuclear, fusion, geothermal, and solar energy technologies and in the field of environmental control. The workshop activities are summarized

  6. Report of the surface science workshop

    Energy Technology Data Exchange (ETDEWEB)

    Somorjai, G.A.; Yates, J.T. Jr.; Clinton, W.

    1977-03-01

    A three-day workshop was held to review the various areas of energy development and technology in which surface science plays major roles and makes major contributions, and to identify the major surface-science-related problem areas in the fields with ERDA's mission in the fossil, nuclear, fusion, geothermal, and solar energy technologies and in the field of environmental control. The workshop activities are summarized. (GHT)

  7. Progress in surface and membrane science

    CERN Document Server

    Cadenhead, D A; Rosenberg, M D

    1975-01-01

    Progress in Surface and Membrane Science, Volume 9 covers the developments in surface and membrane science. The book discusses the physical adsorption of gases and vapors in micropores; the chemisorption theory; and the role of radioisotopes in the studies of chemisorption and catalysis. The text also describes the interaction of ions with monolayers; and the isolation and characterization of mycoplasma membranes. Chemists, physical chemists, and microbiologists will find the book useful.

  8. Surface science tools for nanomaterials characterization

    CERN Document Server

    2015-01-01

    Fourth volume of a 40volume series on nano science and nanotechnology, edited by the renowned scientist Challa S.S.R. Kumar. This handbook gives a comprehensive overview about Surface Science Tools for Nanomaterials Characterization. Modern applications and state-of-the-art techniques are covered and make this volume an essential reading for research scientists in academia and industry.

  9. Progress in surface and membrane science

    CERN Document Server

    Cadenhead, D A

    1976-01-01

    Progress in Surface and Membrane Science, Volume 10 covers the advances in surface and membrane science. The book discusses the selective changes of cellular particles influencing sedimentation properties; and the rotating disk and ring-disk electrodes in investigations of surface phenomena at the metal-electrolyte interface. The text also describes the membrane potential of phospholipid bilayer and biological membranes; the adsorption of surfactant monolayers at gas/liquid and liquid/liquid interfaces; and the enzymes immobilized on glass. Chemists and people involved in electrochemistry will

  10. Progress in surface and membrane science

    CERN Document Server

    Cadenhead, D A

    1981-01-01

    Progress in Surface and Membrane Science, Volume 14 covers the advances in the study of surface and membrane science. The book discusses statistical thermodynamics of monolayer adsorption from gas and liquid mixtures on homogeneous and heterogeneous solid surfaces; and the structure of the boundary layers of liquids and its influence on the mass transfer in fine pores. The text then describes the coupling of ionic and non-electrolyte fluxes in ion selective membranes; the electrocatalytic properties of matalloporphins at the interface; and the adsorption from binary gas and liquid phases. Phas

  11. Progress in surface and membrane science

    CERN Document Server

    Danielli, J F; Cadenhead, D A

    1973-01-01

    Progress in Surface and Membrane Science, Volume 7 covers the developments in the study of surface and membrane science. The book discusses the theoretical and experimental aspects of the van der Waals forces; the electric double layer on the semiconductor-electrolyte interface; and the long-range and short-range order in adsorbed films. The text also describes the hydrodynamical theory of surface shear viscosity; the structure and properties of monolayers of synthetic polypeptides at the air-water interface; and the structure and molecular dynamics of water. The role of glycoproteins in cell

  12. Technical activities, 1990: Surface Science Division

    International Nuclear Information System (INIS)

    Powell, C.J.

    1991-05-01

    The report summarizes technical activities and accomplishments of the NIST Surface Science Division during Fiscal Year 1990. Overviews are presented of the Division and of its three constituent groups: Surface Dynamical Processes, Thin Films and Interfaces, and Surface Spectroscopies and Standards. These overviews are followed by reports of selected technical accomplishments during the year. A summary is given of Division outputs and interactions that includes lists of publications, talks, committee assignments, seminars (including both Division seminars and Interface Science seminars arranged through the Division), conferences organized, and a standard reference material certified. Finally, lists are given of Division staff and of guest scientists who have worked in the Division during the past year

  13. Surface analysis methods in materials science

    CERN Document Server

    Sexton, Brett; Smart, Roger

    1992-01-01

    The idea for this book stemmed from a remark by Philip Jennings of Murdoch University in a discussion session following a regular meeting of the Australian Surface Science group. He observed that a text on surface analysis and applica­ tions to materials suitable for final year undergraduate and postgraduate science students was not currently available. Furthermore, the members of the Australian Surface Science group had the research experience and range of coverage of sur­ face analytical techniques and applications to provide a text for this purpose. A of techniques and applications to be included was agreed at that meeting. The list intended readership of the book has been broadened since the early discussions, particularly to encompass industrial users, but there has been no significant alter­ ation in content. The editors, in consultation with the contributors, have agreed that the book should be prepared for four major groups of readers: - senior undergraduate students in chemistry, physics, metallur...

  14. Radiation Level Changes at RAM Package Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Opperman, Erich [Washington Savannah River Company; Hawk, Mark B [ORNL; Kapoor, Ashok [U.S. Department of Energy, Office of Packaging and Transportation; Natali, Ronald [R. B. Natali Consulting, Inc.

    2010-01-01

    This paper will explore design considerations required to meet the regulations that limit radiation level variations at external surfaces of radioactive material (RAM) packages. The radiation level requirements at package surfaces (e.g. TS-R-1 paragraphs 531 and 646) invoke not only maximum radiation levels, but also strict limits on the allowable increase in the radiation level during transport. This paper will explore the regulatory requirements by quantifying the amount of near surface movement and/or payload shifting that results in a 20% increase in the radiation level at the package surface. Typical IP-2, IP-3, Type A and Type B packaging and source geometries will be illustrated. Variations in surface radiation levels are typically the result of changes in the geometry of the surface due to an impact, puncture or crush event, or shifting and settling of radioactive contents.

  15. Surface science principles and current applications

    CERN Document Server

    Taglauer, E; Wandelt, K

    1996-01-01

    Modern technologies increasingly rely on low-dimensional physics at interfaces and in thin-films and nano-structures. Surface science holds a key position in providing the experimental methods and theoretical models for a basic understanding of these effects. This book includes case studies and status reports about research topics such as: surface structure determination by tensor-LEED and surface X-ray diffraction; the preparation and detection of low-dimensional electronic surface states; quantitative surface compositional analysis; the dynamics of adsorption and reaction of adsorbates, e.g. kinetic oscillations; the characterization and control of thin-film and multilayer growth including the influence of surfactants; a critical assessment of the surface physics approach to heterogeneous catalysis.

  16. Ciencia: Nivel A (Science: Level A).

    Science.gov (United States)

    Duron, Dolores; And Others

    A teacher's manual was developed for an elementary level science course in Spanish as part of an immersion program for English speaking children. The Level A manual is designed for kindergarten and grade 1 pupils. The five units cover the basic concepts of the weather, colors, animals, plants, and the five senses. Each unit includes vocabulary,…

  17. Surface Chloride Levels in Colorado Structural Concrete

    Science.gov (United States)

    2018-01-01

    This project focused on the chloride-induced corrosion of reinforcing steel in structural concrete. The primary goal of this project is to analyze the surface chloride concentration level of the concrete bridge decks throughout Colorado. The study in...

  18. Recent progress in surface science 3

    CERN Document Server

    Danielli, J F; Rosenberg, M D

    2013-01-01

    Recent Progress in Surface Science, Volume 3 covers topics on the structure and mechanisms of the cell membranes. The book discusses the incorporation of chemisorbed species; the recent developments in the study of epitaxy; and the ""diffusion"" or ""hydride"" component of overpotential at cathodes of the ""platinum metals"". The text also describes the mechanism of hydrogen exchange in proteins; the nuclear magnetic resonance studies of lipids, lipoproteins, and cell membranes; and the monolayers of synthetic phospholipids. The formation, electrical properties, transport, and excitability cha

  19. Life Sciences Implications of Lunar Surface Operations

    Science.gov (United States)

    Chappell, Steven P.; Norcross, Jason R.; Abercromby, Andrew F.; Gernhardt, Michael L.

    2010-01-01

    The purpose of this report is to document preliminary, predicted, life sciences implications of expected operational concepts for lunar surface extravehicular activity (EVA). Algorithms developed through simulation and testing in lunar analog environments were used to predict crew metabolic rates and ground reaction forces experienced during lunar EVA. Subsequently, the total metabolic energy consumption, the daily bone load stimulus, total oxygen needed, and other variables were calculated and provided to Human Research Program and Exploration Systems Mission Directorate stakeholders. To provide context to the modeling, the report includes an overview of some scenarios that have been considered. Concise descriptions of the analog testing and development of the algorithms are also provided. This document may be updated to remain current with evolving lunar or other planetary surface operations, assumptions and concepts, and to provide additional data and analyses collected during the ongoing analog research program.

  20. Level crossing analysis of growing surfaces

    International Nuclear Information System (INIS)

    Shahbazi, F; Sobhanian, S; Tabar, M Reza Rahimi; Khorram, S; Frootan, G R; Zahed, H

    2003-01-01

    We investigate the average frequency of positive slope ν + α , crossing the height α = h - h-bar in the surface growing processes. The exact level crossing analysis of the random deposition model and the Kardar-Parisi-Zhang equation in the strong coupling limit before creation of singularities is given

  1. Surface-to-surface registration using level sets

    DEFF Research Database (Denmark)

    Hansen, Mads Fogtmann; Erbou, Søren G.; Vester-Christensen, Martin

    2007-01-01

    This paper presents a general approach for surface-to-surface registration (S2SR) with the Euclidean metric using signed distance maps. In addition, the method is symmetric such that the registration of a shape A to a shape B is identical to the registration of the shape B to the shape A. The S2SR...... problem can be approximated by the image registration (IR) problem of the signed distance maps (SDMs) of the surfaces confined to some narrow band. By shrinking the narrow bands around the zero level sets the solution to the IR problem converges towards the S2SR problem. It is our hypothesis...... that this approach is more robust and less prone to fall into local minima than ordinary surface-to-surface registration. The IR problem is solved using the inverse compositional algorithm. In this paper, a set of 40 pelvic bones of Duroc pigs are registered to each other w.r.t. the Euclidean transformation...

  2. Decommissioning high-level waste surface facilities

    International Nuclear Information System (INIS)

    1978-04-01

    The protective storage, entombment and dismantlement options of decommissioning a High-Level Waste Surface Facility (HLWSF) was investigated. A reference conceptual design for the facility was developed based on the designs of similar facilities. State-of-the-art decommissioning technologies were identified. Program plans and cost estimates for decommissioning the reference conceptual designs were developed. Good engineering design concepts were on the basis of this work identified

  3. System-level musings about system-level science (Invited)

    Science.gov (United States)

    Liu, W.

    2009-12-01

    In teleology, a system has a purpose. In physics, a system has a tendency. For example, a mechanical system has a tendency to lower its potential energy. A thermodynamic system has a tendency to increase its entropy. Therefore, if geospace is seen as a system, what is its tendency? Surprisingly or not, there is no simple answer to this question. Or, to flip the statement, the answer is complex, or complexity. We can understand generally why complexity arises, as the geospace boundary is open to influences from the solar wind and Earth’s atmosphere and components of the system couple to each other in a myriad of ways to make the systemic behavior highly nonlinear. But this still begs the question: What is the system-level approach to geospace science? A reductionist view might assert that as our understanding of a component or subsystem progresses to a certain point, we can couple some together to understand the system on a higher level. However, in practice, a subsystem can almost never been observed in isolation with others. Even if such is possible, there is no guarantee that the subsystem behavior will not change when coupled to others. Hence, there is no guarantee that a subsystem, such as the ring current, has an innate and intrinsic behavior like a hydrogen atom. An absolutist conclusion from this logic can be sobering, as one would have to trace a flash of aurora to the nucleosynthesis in the solar core. The practical answer, however, is more promising; it is a mix of the common sense we call reductionism and awareness that, especially when strongly coupled, subsystems can experience behavioral changes, breakdowns, and catastrophes. If the stock answer to the systemic tendency of geospace is complexity, the objective of the system-level approach to geospace science is to define, measure, and understand this complexity. I will use the example of magnetotail dynamics to illuminate some key points in this talk.

  4. Dynamics of gas-surface interactions atomic-level understanding of scattering processes at surfaces

    CERN Document Server

    Díez Muniño, Ricardo

    2013-01-01

    This book gives a representative survey of the state of the art of research on gas-surface interactions. It provides an overview of the current understanding of gas surface dynamics and, in particular, of the reactive and non-reactive processes of atoms and small molecules at surfaces. Leading scientists in the field, both from the theoretical and the experimental sides, write in this book about their most recent advances. Surface science grew as an interdisciplinary research area over the last decades, mostly because of new experimental technologies (ultra-high vacuum, for instance), as well as because of a novel paradigm, the ‘surface science’ approach. The book describes the second transformation which is now taking place pushed by the availability of powerful quantum-mechanical theoretical methods implemented numerically. In the book, experiment and theory progress hand in hand with an unprecedented degree of accuracy and control. The book presents how modern surface science targets the atomic-level u...

  5. Thermochemical Surface Engineering: A Playground for Science and Innovation

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lundin; Dahl, Kristian Vinter; Jellesen, Morten Stendahl

    2017-01-01

    Surface engineering by thermochemical processing is the intentional change of the composition of a material at elevated temperature with the purpose to improve materials performance. In thermochemical processing components from the starting material are essential in the development of the phases...... at the surface. Current research and innovation activities are used to exemplify thermochemical surface engineering and the interplay of science and innovation. The examples given encompass aspects of the synthesis of extremely porous materials, low temperature surface hardening of stainless steel, surface...

  6. Spin polarized electrons in surface science

    International Nuclear Information System (INIS)

    Siegmann, H.C.

    1983-01-01

    The potentialities of spin-polarised electron beams as a probe of surface magnetic properties are outlined. Elastic as well as inelastic scattering of electrons from solid surfaces are considered. (G.Q.)

  7. Surface Science at the Solid Liquid Interface

    Science.gov (United States)

    1993-10-06

    prominent experimental avenue, developed originally by Hubbard et al,_ involves emersing monocrystalline elec- As for metal surfaces in ultrahigh vacuum...reliable means of both preparing and dosateizn ordered monocrystalline metal surfaces in UHV has led to ing appropriate molecular components of...surface atoms in place of bottom panel of Fig. 2, equal intensity contours are shown 23 underlying surface atoms, the compression is 24/23 - I in the

  8. Factors Influencing Exemplary Science Teachers' Levels of Computer Use

    Science.gov (United States)

    Hakverdi, Meral; Dana, Thomas M.; Swain, Colleen

    2011-01-01

    The purpose of this study was to examine exemplary science teachers' use of technology in science instruction, factors influencing their level of computer use, their level of knowledge/skills in using specific computer applications for science instruction, their use of computer-related applications/tools during their instruction, and their…

  9. Workshop on surface and interface science at the ESRF

    Energy Technology Data Exchange (ETDEWEB)

    Norris, C.; Stierle, A.; Kasper, N.; Dosch, H.; Schmidt, S.; Hufner, S.; Moritz, W.; Fedley, Ch.S.; Rossi, G.; Durr Hermann, A.; Rohlsberger, R.; Dalmas, J.; Oughaddou, H.; Leandri, Ch.; Gay, J.M.; Treglia, G.; Le Lay, G.; Aufray, B.; Bunk, O.; Johnson, R.L.; Frenken, J.W.M.; Lucas, C.A.; Bauer, G.; Zhong, Z.; Springholz, G.; Lechner, R.; Stang, J.; Schulli, T.; Metzger, T.H.; Holy, V.; Woodruff, D.P.; Dellera, C.; Zegenhagen, J.; Robinson, I.; Malachias, A.; Schulli, T.U.; Magalhaes-Paniago, R.; Stoffel, M.; Schmidt, O.G.; Boragno, C.; Buatier de Mongeot, F.; Valbusa, U.; Felici, R.; Yacoby, Y.; Bedzyk, M.J.; Van der Veen, J.F

    2004-07-01

    The main aim of the workshop is to reflect the future of surface and interface research at the high brilliance synchrotron radiation source ESRF taking into account experimental facilities which are becoming available at new synchrotron radiation facilities in Europe. 6 sessions have been organized: 1) surface and interface research and synchrotron radiation - today and tomorrow -, 2) aspects of surface and interface research, 3) real surfaces and interfaces, 4) synchrotron techniques in surface and interface research, 5) new directions in surface and interface research, and 6) surface and interface science at ESRF. This document gathers the abstracts of the presentations.

  10. Workshop on surface and interface science at the ESRF

    International Nuclear Information System (INIS)

    Norris, C.; Stierle, A.; Kasper, N.; Dosch, H.; Schmidt, S.; Hufner, S.; Moritz, W.; Fedley, Ch.S.; Rossi, G.; Durr Hermann, A.; Rohlsberger, R.; Dalmas, J.; Oughaddou, H.; Leandri, Ch.; Gay, J.M.; Treglia, G.; Le Lay, G.; Aufray, B.; Bunk, O.; Johnson, R.L.; Frenken, J.W.M.; Lucas, C.A.; Bauer, G.; Zhong, Z.; Springholz, G.; Lechner, R.; Stang, J.; Schulli, T.; Metzger, T.H.; Holy, V.; Woodruff, D.P.; Dellera, C.; Zegenhagen, J.; Robinson, I.; Malachias, A.; Schulli, T.U.; Magalhaes-Paniago, R.; Stoffel, M.; Schmidt, O.G.; Boragno, C.; Buatier de Mongeot, F.; Valbusa, U.; Felici, R.; Yacoby, Y.; Bedzyk, M.J.; Van der Veen, J.F.

    2004-01-01

    The main aim of the workshop is to reflect the future of surface and interface research at the high brilliance synchrotron radiation source ESRF taking into account experimental facilities which are becoming available at new synchrotron radiation facilities in Europe. 6 sessions have been organized: 1) surface and interface research and synchrotron radiation - today and tomorrow -, 2) aspects of surface and interface research, 3) real surfaces and interfaces, 4) synchrotron techniques in surface and interface research, 5) new directions in surface and interface research, and 6) surface and interface science at ESRF. This document gathers the abstracts of the presentations

  11. Factors influencing exemplary science teachers' levels of computer use

    Science.gov (United States)

    Hakverdi, Meral

    This study examines exemplary science teachers' use of technology in science instruction, factors influencing their level of computer use, their level of knowledge/skills in using specific computer applications for science instruction, their use of computer-related applications/tools during their instruction, and their students' use of computer applications/tools in or for their science class. After a relevant review of the literature certain variables were selected for analysis. These variables included personal self-efficacy in teaching with computers, outcome expectancy, pupil-control ideology, level of computer use, age, gender, teaching experience, personal computer use, professional computer use and science teachers' level of knowledge/skills in using specific computer applications for science instruction. The sample for this study includes middle and high school science teachers who received the Presidential Award for Excellence in Science Teaching Award (sponsored by the White House and the National Science Foundation) between the years 1997 and 2003 from all 50 states and U.S. territories. Award-winning science teachers were contacted about the survey via e-mail or letter with an enclosed return envelope. Of the 334 award-winning science teachers, usable responses were received from 92 science teachers, which made a response rate of 27.5%. Analysis of the survey responses indicated that exemplary science teachers have a variety of knowledge/skills in using computer related applications/tools. The most commonly used computer applications/tools are information retrieval via the Internet, presentation tools, online communication, digital cameras, and data collection probes. Results of the study revealed that students' use of technology in their science classroom is highly correlated with the frequency of their science teachers' use of computer applications/tools. The results of the multiple regression analysis revealed that personal self-efficacy related to

  12. Surface science models of CoMoS hydrodesulfurisation catalysts

    NARCIS (Netherlands)

    Jong, de A.M.; Beer, de V.H.J.; Veen, van J.A.R.; Niemantsverdriet, J.W.; Froment, G.F.; Delmon, B.; Grange, P.

    1997-01-01

    Characterization of supported catalysts with surface spectroscopic techniques is often limited due to restraints imposed by the support material. The use of flat conducting substrates as a model support offers a way to apply these techniques to their full potential. Such surface science models of

  13. Inter-level relations in computer science, biology, and psychology

    NARCIS (Netherlands)

    Boogerd, F.; Bruggeman, F.; Jonker, C.M.; Looren de Jong, H.; Tamminga, A.; Treur, J.; Westerhoff, H.V.; Wijngaards, W.C.A.

    2002-01-01

    Investigations into inter-level relations in computer science, biology and psychology call for an empirical turn in the philosophy of mind. Rather than concentrate on a priori discussions of inter-level relations between 'completed' sciences, a case is made for the actual study of the way

  14. Inter-level relations in computer science, biology and psychology

    NARCIS (Netherlands)

    Boogerd, F.C.; Bruggeman, F.J.; Jonker, C.M.; Looren De Jong, H.; Tamminga, A.M.; Treur, J.; Westerhoff, H.V.; Wijngaards, W.C.A.

    2002-01-01

    Investigations into inter-level relations in computer science, biology and psychology call for an empirical turn in the philosophy of mind. Rather than concentrate on a priori discussions of inter-level relations between "completed" sciences, a case is made for the actual study of the way

  15. Inter-level relations in computer science, biology, and psychology

    NARCIS (Netherlands)

    Boogerd, Fred; Bruggeman, Frank; Jonker, Catholijn; Looren de Jong, Huib; Tamminga, Allard; Treur, Jan; Westerhoff, Hans; Wijngaards, Wouter

    2002-01-01

    Investigations into inter-level relations in computer science, biology and psychology call for an *empirical* turn in the philosophy of mind. Rather than concentrate on *a priori* discussions of inter-level relations between “completed” sciences, a case is made for the actual study of the way

  16. BEST: Bilingual environmental science training: Kindergarten level

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    This booklet is one of a series of bilingual guides to environmental-science learning activities for students to do at home. Lesson objectives, materials required, procedure, vocabulary, and subjects integrated into the lesson are described in English for each lesson. A bilingual glossary, alphabetized by English entries, with Spanish equivalents in both English and Spanish, follows the lesson descriptions, and is itself followed by a bibliography of English-language references. This booklet includes descriptions of six lessons covering the senses of touch and sight, the sense of smell, how to distinguish living and non-living things, cell structures, the skeletal system, and the significance of food groups. 8 figs.

  17. Fermi level on hydrogen terminated diamond surfaces

    Czech Academy of Sciences Publication Activity Database

    Rezek, Bohuslav; Saurer, C.; Nebel, C. E.; Stutzmann, M.; Ristein, J.; Ley, L.; Snidero, E.; Bergonzo, P.

    2003-01-01

    Roč. 82, č. 14 (2003), s. 2266-2268 ISSN 0003-6951 EU Projects: European Commission(XE) HPRN-CT-1999-00139 Grant - others:DFC(DE) NE524-2 Institutional research plan: CEZ:AV0Z1010914 Keywords : atomic force microscope (AFM) * Kelvin probe experiments * diamond surface Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 4.049, year: 2003

  18. Surface enhanced raman spectroscopy analytical, biophysical and life science applications

    CERN Document Server

    Schlücker, Sebastian

    2013-01-01

    Covering everything from the basic theoretical and practical knowledge to new exciting developments in the field with a focus on analytical and life science applications, this monograph shows how to apply surface-enhanced Raman scattering (SERS) for solving real world problems. From the contents: * Theory and practice of SERS * Analytical applications * SERS combined with other analytical techniques * Biophysical applications * Life science applications including various microscopies Aimed at analytical, surface and medicinal chemists, spectroscopists, biophysicists and materials scientists. Includes a Foreword by the renowned Raman spectroscopist Professor Wolfgang Kiefer, the former Editor-in-Chief of the Journal of Raman Spectroscopy.

  19. 7th International Summer Institute in Surface Science

    CERN Document Server

    Howe, Russell

    1986-01-01

    This volume contains review articles which were written by the invited speak­ ers of the seventh International Summer Institute in Surface Science (ISISS), held at the University of Wisconsin - Milwaukee in July 1985. The form of ISISS is a set of tutorial review lectures presented over a one-week period by internationally recognized experts on various aspects of surface science. Each speaker is asked, in addition, to write a review article on his lecture topic. No single volume in the series Chemistry and Physics of Solid Surfaces can possibly cover the entire field of modern surface science. However, the series as a whole is intended to provide experts and students alike with a comprehensive set of reviews and literature references, particularly empha­ sizing the gas-solid interface. The collected articles from previous Summer Institutes have been published under the following titles: Surface Science: Recent Progress and Perspectives, Crit. Rev. Solid State Sci. 4, 125-559 (1974) Chemistry and Physics of ...

  20. Surface science of single-site heterogeneous olefin polymerization catalysts

    OpenAIRE

    Kim, Seong H.; Somorjai, Gabor A.

    2006-01-01

    This article reviews the surface science of the heterogeneous olefin polymerization catalysts. The specific focus is on how to prepare and characterize stereochemically specific heterogeneous model catalysts for the Ziegler–Natta polymerization. Under clean, ultra-high vacuum conditions, low-energy electron irradiation during the chemical vapor deposition of model Ziegler–Natta catalysts can be used to create a “single-site” catalyst film with a surface structure that produces only isotactic ...

  1. Surface science station of the infrared beamline at SPring-8

    International Nuclear Information System (INIS)

    Sakurai, M.; Moriwaki, T.; Kimura, H.; Nishida, S.; Nanba, T.

    2001-01-01

    An experimental station for surface science has been constructed at the infrared beamline (BL43IR) of SPring-8, Japan. The station utilizes synchrotron radiation in the energy range of 100-20000 cm -1 to perform infrared reflection absorption spectroscopy (IRAS) of surfaces. It consists of an experimental section, a preparation chamber, gas handling equipment and a pair of focusing optics. In situ observation of vibrational spectra is possible using both IRAS and high-resolution electron energy loss spectroscopy

  2. Predictors of Student Success in Entry-Level Science Courses

    Science.gov (United States)

    Singh, Mamta K.

    2009-01-01

    Although the educational evaluation process is useful and valuable and is supported by the Higher Education Act, a strong research base for program evaluation of college entry-level science courses is still lacking. Studies in science disciplines such as, biology, chemistry, and physics have addressed various affective and demographic factors and…

  3. The development of surface science in China: Retrospect and prospects

    Energy Technology Data Exchange (ETDEWEB)

    Xie Xide (Fudan University, Shanghai (China))

    1994-01-01

    It is generally agreed that the year of 1977 marked the birth of surface science in China, therefore the length of its history of development is only half of that shown in the title of this volume. Since 1977 laboratories with modern facilities for surface studies have been established in various universities and research institutes. Three open laboratories better equipped than others have been set up in Beijing, Xiamen and Shanghai for surface physics, surface chemistry and applied surface physics, respectively. Five National Conferences on Physics of Surfaces and Interfaces were held in 1982, 1984, 1985, 1988 and 1991. In 1993 China is going to host the Fourth International Conference on the Structure of Surfaces in Shanghai August 16-19 which will serve as a milestone in the history of development of surface science in China. With the access to many overseas laboratories, quite a number of Chinese scientists and students have had opportunities to work and study abroad and have brought back with them experiences acquired. During the Conferences just mentioned, one could witness a number of steady progresses made over the years. In the present review, a brief description about the establishment of some major research facilities and progresses of some of the research is given with emphasis on work related to semiconductor surfaces, interfaces, superlattices, heterojunctions and quantum wells. Although the review nominally covers the development of research in surface science in China, due to the limitation of the capabilities of the author, mostly work done at Fudan University is included. For this the author would like to express her deep apology to many Chinese colleagues whose works have not been properly mentioned

  4. Molecular surface science of heterogeneous catalysis. History and perspective

    International Nuclear Information System (INIS)

    Somorjai, G.A.

    1983-08-01

    A personal account is given of how the author became involved with modern surface science and how it was employed for studies of the chemistry of surfaces and heterogeneous catalysis. New techniques were developed for studying the properties of the surface monolayers: Auger electron spectroscopy, LEED, XPS, molecular beam surface scattering, etc. An apparatus was developed and used to study hydrocarbon conversion reactions on Pt, CO hydrogenation on Rh and Fe, and NH 3 synthesis on Fe. A model has been developed for the working Pt reforming catalyst. The three molecular ingredients that control catalytic properties are atomic surface structure, an active carbonaceous deposit, and the proper oxidation state of surface atoms. 40 references, 21 figures

  5. Molecular surface science of heterogeneous catalysis. History and perspective

    Energy Technology Data Exchange (ETDEWEB)

    Somorjai, G.A.

    1983-08-01

    A personal account is given of how the author became involved with modern surface science and how it was employed for studies of the chemistry of surfaces and heterogeneous catalysis. New techniques were developed for studying the properties of the surface monolayers: Auger electron spectroscopy, LEED, XPS, molecular beam surface scattering, etc. An apparatus was developed and used to study hydrocarbon conversion reactions on Pt, CO hydrogenation on Rh and Fe, and NH/sub 3/ synthesis on Fe. A model has been developed for the working Pt reforming catalyst. The three molecular ingredients that control catalytic properties are atomic surface structure, an active carbonaceous deposit, and the proper oxidation state of surface atoms. 40 references, 21 figures. (DLC)

  6. A molecular surface science study of the structure of adsorbates on surfaces: Importance to lubrication

    International Nuclear Information System (INIS)

    Mate, C.M.

    1986-09-01

    The interaction and bonding of atoms and molecules on metal surfaces is explored under ultra-high vacuum conditions using a variety of surface science techniques: high resolution electron energy loss spectroscopy (HREELS), low energy electron diffraction (LEED), thermal desorption spectroscopy (TDS), Auger electron spectroscopy (AES), work function measurements, and second harmonic generation (SHG). 164 refs., 51 figs., 3 tabs

  7. Predictors of student success in entry-level science courses

    Science.gov (United States)

    Singh, Mamta K.

    Although the educational evaluation process is useful and valuable and is supported by the Higher Education Act, a strong research base for program evaluation of college entry-level science courses is still lacking. Studies in science disciplines such as, biology, chemistry, and physics have addressed various affective and demographic factors and their relationships to student achievement. However, the literature contains little information that specifically addresses student biology content knowledge skills (basics and higher order thinking skills) and identifies factors that affect students' success in entry-level college science courses. These gate-keeping courses require detailed evaluation if the goal of an institution is to increase students' performance and success in these courses. These factors are, in fact, a stepping stone for increasing the number of graduates in Science, Technology, Engineering, and Mathematics (STEM) majors. The present study measured students' biology content knowledge and investigated students' performance and success in college biology, chemistry, and physics entry-level courses. Seven variables---gender, ethnicity, high school Grade Point Average (GPA), high school science, college major, school financial aid support, and work hours were used as independent variables and course final performance as a dichotomous dependent variable. The sample comprised voluntary student participants in entry-level science courses. The study attempted to explore eight research questions. Content knowledge assessments, demographic information analysis, multiple regression analysis, and binary logistic regression analysis were used to address research questions. The results suggested that high school GPA was a consistently good predictor of students' performance and success in entry-level science courses. Additionally, high school chemistry was a significant predictor variable for student success in entry-level biology and chemistry courses

  8. 8th International Summer Institute in Surface Science

    CERN Document Server

    Howe, Russell

    1988-01-01

    This volume contains review articles written by the invited speakers at the eighth International Summer Institute in Surface Science (ISISS 1987), held at the University of Wisconsin-Milwaukee in August of 1987. During the course of ISISS, invited speakers, all internationally recognized experts in the various fields of surface science, present tutorial review lectures. In addition, these experts are asked to write review articles on their lecture topic. Former ISISS speakers serve as advisors concerning the selection of speakers and lecture topics. Em­ phasis is given to those areas which have not been covered in depth by recent Summer Institutes, as well as to areas which have recently gained in significance and in which important progress has been made. Because of space limitations, no individual volume of Chemistry and Physics of Solid Surfaces can possibly cover the whole area of modem surface science, or even give a complete survey of recent pro­ gress in the field. However, an attempt is made to pres...

  9. Computational techniques in tribology and material science at the atomic level

    Science.gov (United States)

    Ferrante, J.; Bozzolo, G. H.

    1992-01-01

    Computations in tribology and material science at the atomic level present considerable difficulties. Computational techniques ranging from first-principles to semi-empirical and their limitations are discussed. Example calculations of metallic surface energies using semi-empirical techniques are presented. Finally, application of the methods to calculation of adhesion and friction are presented.

  10. Revolution in Field Science: Apollo Approach to Inaccessible Surface Exploration

    Science.gov (United States)

    Clark, P. E.

    2010-07-01

    The extraordinary challenge mission designers, scientists, and engineers, faced in planning the first human expeditions to the surface of another solar system body led to the development of a distinctive and even revolutionary approach to field work. Not only were those involved required to deal effectively with the extreme limitation in resources available for and access to a target as remote as the lunar surface; they were required to developed a rigorous approach to science activities ranging from geological field work to deploying field instruments. Principal aspects and keys to the success of the field work are discussed here, including the highly integrated, intensive, and lengthy science planning, simulation, and astronaut training; the development of a systematic scheme for description and documentation of geological sites and samples; and a flexible yet disciplined methodology for site documentation and sample collection. The capability for constant communication with a ‘backroom’ of geological experts who make requests and weigh in on surface operations was innovative and very useful in encouraging rapid dissemination of information to the greater community in general. An extensive archive of the Apollo era science activity related documents provides evidence of the principal aspects and keys to the success of the field work. The Apollo Surface Journal allows analysis of the astronaut’s performance in terms of capability for traveling on foot, documentation and sampling of field stations, and manual operation of tools and instruments, all as a function of time. The application of these analysis as ‘lessons learned’ for planning the next generation of human or robotic field science activities on the Moon and elsewhere are considered here as well.

  11. A Level Set Discontinuous Galerkin Method for Free Surface Flows

    DEFF Research Database (Denmark)

    Grooss, Jesper; Hesthaven, Jan

    2006-01-01

    We present a discontinuous Galerkin method on a fully unstructured grid for the modeling of unsteady incompressible fluid flows with free surfaces. The surface is modeled by embedding and represented by a levelset. We discuss the discretization of the flow equations and the level set equation...

  12. Evaluation of the levels of phthalate ester plasticizers in surface ...

    African Journals Online (AJOL)

    Evaluation of the levels of phthalate ester plasticizers in surface water of Ethiope ... Gas chromatography (GC) coupled with mass spectrometer (MS) was used to ... with their common use in plastic materials and other industrial chemicals.

  13. EDITORIAL: Focus on Advances in Surface and Interface Science 2008 FOCUS ON ADVANCES IN SURFACE AND INTERFACE SCIENCE 2008

    Science.gov (United States)

    Scheffler, Matthias; Schneider, Wolf-Dieter

    2008-12-01

    Basic research in surface and interface science is highly interdisciplinary, covering the fields of physics, chemistry, biophysics, geo-, atmospheric and environmental sciences, material science, chemical engineering, and more. The various phenomena are interesting by themselves, and they are most important in nearly all modern technologies, as for example electronic, magnetic, and optical devices, sensors, catalysts, lubricants, hard and thermal-barrier coatings, protection against corrosion and crack formation under harsh environments. In fact, detailed understanding of the elementary processes at surfaces is necessary to support and to advance the high technology that very much founds the prosperity and lifestyle of our society. Current state-of-the-art experimental studies of elementary processes at surfaces, of surface properties and functions employ a variety of sophisticated tools. Some are capable of revealing the location and motion of individual atoms. Others measure excitations (electronic, magnetic and vibronic), employing, for example, special light sources such as synchrotrons, high magnetic fields, or free electron lasers. The surprising variety of intriguing physical phenomena at surfaces, interfaces, and nanostructures also pose a persistent challenge for the development of theoretical descriptions, methods, and even basic physical concepts. This second focus issue on the topic of 'Advances in Surface and Interface Science' in New Journal of Physics, following on from last year's successful collection, provides an exciting synoptic view on the latest pertinent developments in the field. Focus on Advances in Surface and Interface Science 2008 Contents Organic layers at metal/electrolyte interfaces: molecular structure and reactivity of viologen monolayers Stephan Breuer, Duc T Pham, Sascha Huemann, Knud Gentz, Caroline Zoerlein, Ralf Hunger, Klaus Wandelt and Peter Broekmann Spin polarized d surface resonance state of fcc Co/Cu(001) K Miyamoto, K

  14. Pre-college Science Experiences; Timing and Causes of Gender Influence Science Interest Levels

    Science.gov (United States)

    Kaplita, E.; Reed, D. E.; McKenzie, D. A.; Jones, R.; May, L. W.

    2015-12-01

    It is known that female students tend to turn away from science during their pre-college years. Experiences during this time are not limited to the classroom, as cultural influences extend beyond K-12 science education and lead to the widely studied reduction in females in STEM fields. This has a large impact on climate science because currently relatively little effort is put into K-12 climate education, yet this is when college attitudes towards science are formed. To help quantify these changes, 400 surveys were collected from 4 different colleges in Oklahoma. Student responses were compared by gender against student experiences (positive and negative), and interest in science. Results of our work show that females tend to have their first positive experience with science at a younger age with friends, family and in the classroom, and have more of an interest in science when they are younger. Males in general like experiencing science more on their own, and surpass the interest levels of females late in high school and during college. While in college, males are more comfortable with science content than females, and males enjoy math and statistics more while those aspects of science were the largest areas of dislike in females. Understanding how to keep students (particularly female) interested in science as they enter their teen years is extremely important in preventing climate misconceptions in the adult population. Potential small changes such as hosting K-12 climate outreach events and including parents, as opposed to just inviting students, could greatly improve student experiences with science and hence, their understanding of climate science. Importantly, a greater focus on female students is warranted.

  15. Advancing the Science of Community-Level Interventions

    Science.gov (United States)

    Beehler, Sarah; Deutsch, Charles; Green, Lawrence W.; Hawe, Penelope; McLeroy, Kenneth; Miller, Robin Lin; Rapkin, Bruce D.; Schensul, Jean J.; Schulz, Amy J.; Trimble, Joseph E.

    2011-01-01

    Community interventions are complex social processes that need to move beyond single interventions and outcomes at individual levels of short-term change. A scientific paradigm is emerging that supports collaborative, multilevel, culturally situated community interventions aimed at creating sustainable community-level impact. This paradigm is rooted in a deep history of ecological and collaborative thinking across public health, psychology, anthropology, and other fields of social science. The new paradigm makes a number of primary assertions that affect conceptualization of health issues, intervention design, and intervention evaluation. To elaborate the paradigm and advance the science of community intervention, we offer suggestions for promoting a scientific agenda, developing collaborations among professionals and communities, and examining the culture of science. PMID:21680923

  16. Investigation of Inquiry-based Science Pedagogy among Middle Level Science Teachers: A Qualitative Study

    Science.gov (United States)

    Weiland, Sunny Minelli

    This study implemented a qualitative approach to examine the phenomenon of "inquiry-based science pedagogy or inquiry instruction" as it has been experienced by individuals. Data was collected through online open-ended surveys, focus groups, and teacher reported self-reflections to answer the research questions: 1) How do middle level science teachers conceptualize "inquiry-based instruction?" 2) What are preferred instructional strategies for implementation in middle level science classrooms? And 3) How do middle level science teachers perceive the connection between science instruction and student learning? The participants within this research study represent 33 percent of teachers in grades 5 through 9 within six school districts in northeastern Pennsylvania. Of the 12 consent forms originally obtained, 10 teachers completed all three phases of the data collection, including the online survey, participation in focus groups, and teacher self-reflection. 60 percent of the participants taught only science, and 40 percent taught all content areas. Of the ten participants, 50 percent were certified teachers of science and 50 percent were certified as teachers of elementary education. 70 percent of the research participants reflected having obtained a master's, with 60 percent of these degrees being received in areas of education, and 10 percent in the area of science. The research participants have a total of 85 collective years of experience as professional educators, with the average years of experience being 8.5 years. Analysis of data revealed three themes related to research question #1) How do middle-level science teachers conceptualize inquiry-based instruction? and sub-question #1) How do middle-level science teachers characterize effective instruction? The themes that capture the essence of teachers' formulation of inquiry-based instruction that emerged in this study were student centered, problem solving, and hands-on . Analysis of data revealed one theme

  17. GNVQ science at advanced level: motivation and self-esteem

    Science.gov (United States)

    Solomon, J.

    1995-07-01

    An interview study carried out in the pilot year of the new GNVQ in science at A-level has shown that the use of grading criteria, which require independent learning, as a method of assessment is better for students' motivation and self-esteem.

  18. A statistical method to get surface level air-temperature from satellite observations of precipitable water

    Digital Repository Service at National Institute of Oceanography (India)

    Pankajakshan, T.; Shikauchi, A; Sugimori, Y.; Kubota, M.

    -T a and precipitable water. The rms errors of the SSMI-T a , in this case are found to be reduced to 1.0°C. 1. Introduction Satellite derived surface-level meteorological parameters are considered to be a better alternative to sparse ship... Vol. 49, pp. 551 to 558. 1993 A Statistical Method to Get Surface Level Air-Temperature from Satellite Observations of Precipitable Water PANKAJAKSHAN THADATHIL*, AKIRA SHIKAUCHI, YASUHIRO SUGIMORI and MASAHISA KUBOTA School of Marine Science...

  19. Surface science in hernioplasty: The role of plasma treatments

    Science.gov (United States)

    Nisticò, Roberto; Magnacca, Giuliana; Martorana, Selanna

    2017-10-01

    The aim of this review is to clarify the importance of surface modifications induced in biomaterials for hernia-repair application. Starting from the pioneering experiences involving proto-materials as ancient prosthesis, a historical excursus between the biomaterials used in hernioplasty was realized. Subsequently, after the revolutionary discovery of stereoregular polymerization followed by the PP application in the biomedical field performed by the surgeon F. Usher, a comparative study on different hernia-repair meshes available was realized in order to better understand all the outstanding problems and possible future developments. Furthermore, since many unsolved problems on prosthetic devices implantation are linked to phenomena occurring at the interface between the biomaterials surface and the body fluids, the importance of surface science in hernioplasty was highlighted and case studies of new surface-modified generations of prosthesis presented. The results discussed in the following evidence how the surface study are becoming increasingly important for a proper knowledge of issues related to the interaction between the living matter and the artificial prostheses.

  20. Reducing Motional Decoherence in Ion Traps with Surface Science Methods

    Science.gov (United States)

    Haeffner, Hartmut

    2014-03-01

    Many trapped ions experiments ask for low motional heating rates while trapping the ions close to trapping electrodes. However, in practice small ion-electrode distances lead to unexpected high heating rates. While the mechanisms for the heating is still unclear, it is now evident that surface contamination of the metallic electrodes is at least partially responsible for the elevated heating rates. I will discuss heating rate measurements in a microfabricated surface trap complemented with basic surface science studies. We monitor the elemental surface composition of the Cu-Al alloy trap with an Auger spectrometer. After bake-out, we find a strong Carbon and Oxygen contamination and heating rates of 200 quanta/s at 1 MHz trap frequency. After removing most of the Carbon and Oxygen with Ar-Ion sputtering, the heating rates drop to 4 quanta/s. Interestingly, we still measure the decreased heating rate even after the surface oxidized from the background gas throughout a 40-day waiting time in UHV.

  1. EDITORIAL: From reciprocal space to real space in surface science From reciprocal space to real space in surface science

    Science.gov (United States)

    Bartels, Ludwig; Ernst, Karl-Heinz

    2012-09-01

    This issue is dedicated to Karl-Heinz Rieder on the occasion of his 70th birthday. It contains contributions written by his former students and colleagues from all over the world. Experimental techniques based on free electrons, such as photoelectron spectroscopy, electron microscopy and low energy electron diffraction (LEED), were foundational to surface science. While the first revealed the band structures of materials, the second provided nanometer scale imagery and the latter elucidated the atomic scale periodicity of surfaces. All required an (ultra-)high vacuum, and LEED illustrated impressively that adsorbates, such as carbon monoxide, hydrogen or oxygen, can markedly and periodically restructure surfaces from their bulk termination, even at pressures ten orders of magnitude or more below atmospheric. Yet these techniques were not generally able to reveal atomic scale surface defects, nor could they faithfully show adsorption of light atoms such as hydrogen. Although a complete atom, helium can also be regarded as a wave with a de Broglie wavelength that allows the study of surface atomic periodicities at a delicateness and sensitivity exceeding that of electrons-based techniques. In combination, these and other techniques generated insight into the periodicity of surfaces and their vibrational properties, yet were limited to simple and periodic surface setups. All that changed with the advent of scanning tunneling microscopy (STM) roughly 30 years ago, allowing real space access to surface defects and individual adsorbates. Applied at low temperatures, not only can STM establish a height profile of surfaces, but can also perform spectroscopy and serve as an actuator capable of rearranging individual species at atomic scale resolution. The direct and intuitive manner in which STM provided access as a spectator and as an actor to the atomic scale was foundational to today's surface science and to the development of the concepts of nanoscience in general. The

  2. Surface core-level shifts for simple metals

    DEFF Research Database (Denmark)

    Aldén, Magnus; Skriver, Hans Lomholt; Johansson, Börje

    1994-01-01

    screening, whereby a SCLS becomes equivalent to the surface segregation energy of a core-ionized atom, a quantity we obtain by separate bulk and surface impurity calculations. The results are in good agreement with experiment in most of those cases where the data originates from single-crystal measurements....... We discuss the surface shifts of the electrostatic potentials and the band centers in order to trace the microscopic origin of the SCLS in the simple metals and find that the anomalous subsurface core-level shifts in beryllium are caused by charge dipoles, which persist several layers into the bulk...

  3. The Evaluation of Burnout Levels of Sports Sciences Faculty Students

    Science.gov (United States)

    Kocaeksi, Serdar

    2016-01-01

    The aim of this research is to evaluate the burnout levels of sports sciences faculty students in terms of some other variables. 46 Female (Age, M: 20.88 ± 1.86) and 107 male (Age, M: 22.15 ± 2.15) in total 153 students participated in this research. Maslach Burnout Inventory-Student Form (MBI-SF) was used for data collection. Descriptive…

  4. Surface and catalysis science in the Materials and Molecular Research Division

    International Nuclear Information System (INIS)

    1980-01-01

    Surface science studies at Lawrence Berkeley Laboratory are detailed. Subject areas include: structure of surfaces and adsorbed monolayers; reduction and oxidation of surfaces; catalytic chemistry; and structure of interfaces and thin films

  5. Automatic Measurement of Low Level Contamination on Concrete Surfaces

    International Nuclear Information System (INIS)

    Tachibana, M.; Itoh, H.; Shimada, T.; Yanagihara, S.

    2002-01-01

    Automatic measurement of radioactivity is necessary for considering cost effectiveness in final radiological survey of building structures in decommissioning nuclear facilities. The RAPID (radiation measuring pilot device for surface contamination) was developed to be applied to automatic measurement of low level contamination on concrete surfaces. The RAPID has a capability to measure contamination with detection limit of 0.14 Bq/cm2 for 60Co in 30 seconds of measurement time and its efficiency is evaluated to be 5 m2/h in a normal measurement option. It was confirmed that low level contamination on concrete surfaces could be surveyed by the RAPID efficiently compared with direct measurement by workers through its actual application

  6. Immobilized enzymes: understanding enzyme - surface interactions at the molecular level.

    Science.gov (United States)

    Hoarau, Marie; Badieyan, Somayesadat; Marsh, E Neil G

    2017-11-22

    Enzymes immobilized on solid supports have important and industrial and medical applications. However, their uses are limited by the significant reductions in activity and stability that often accompany the immobilization process. Here we review recent advances in our understanding of the molecular level interactions between proteins and supporting surfaces that contribute to changes in stability and activity. This understanding has been facilitated by the application of various surface-sensitive spectroscopic techniques that allow the structure and orientation of enzymes at the solid/liquid interface to be probed, often with monolayer sensitivity. An appreciation of the molecular interactions between enzyme and surface support has allowed the surface chemistry and method of enzyme attachement to be fine-tuned such that activity and stability can be greatly enhanced. These advances suggest that a much wider variety of enzymes may eventually be amenable to immobilization as green catalysts.

  7. Origin of metallic surface core-level shifts

    DEFF Research Database (Denmark)

    Aldén, Magnus; Skriver, Hans Lomholt; Abrikosov, I. A.

    1995-01-01

    The unique property of the open 4f energy shell in the lanthanide metals is used to show that the initial-state energy shift gives an insufficient description of surface core-level shifts. Instead a treatment, which fully includes the final-state screening, account for the experimentally observed...

  8. Surface science models of CoMoS hydrodesulfurisation catalysts

    Energy Technology Data Exchange (ETDEWEB)

    De Jong, A.M.; De Beer, V.H.J.; Van Veen, J.A.R.; Niemantsverdriet, J.W. [Schuit Institute of Catalysis, Eindhoven University of Technology, Eindhoven (Netherlands)

    1997-07-01

    Characterization of supported catalysts with surface spectroscopic techniques is often limited due to restraints imposed by the support material. The use of flat conducting substrates as a model support offers a way to apply these techniques to their full potential. Such surface science models of silica and alumina supported CoMoS catalysts have been made by impregnating thin SiO{sub 2} and Al{sub 2}O{sub 3} films with a solution of nitrilotriacetic acid (NTA) complexes of cobalt and molybdenum. X-ray Photoelectron Spectroscopy (XPS) spectra indicate that the order in which cobalt and molybdenum transfer to the sulfided state is reversed with respect to oxidic Co and Mo systems prepared by conventional methods, implying that NTA complexation retards the sulfidation of cobalt to temperatures where MoS{sub 2} is already formed. Catalytic tests show that the CoMoS model catalysts exhibit activities for thiophene desulfurisation and product distributions similar to those of their high surface area counterparts. 25 refs.

  9. Knowledge Levels of Pre-Service Science Teachers on Radioactivity

    Directory of Open Access Journals (Sweden)

    Zehra Molu

    2016-09-01

    Full Text Available This study aims to determine the knowledge levels of pre-service science teachers about radioactivity. A knowledge test was administered to 56 pre-service science teachers participated in the General Chemistry I course in the fall semester of 2014-15 academic year. Papers derived from the pre-service science teachers were read and evaluated, and the responses were classified as “accurate", "misconception", "wrong" and "empty" categories for open-ended questions and the responses to the multiple-choice questions were classified as "right" and "wrong". The pre-service science teachers’ correct response rates were between 9 % (definition of “nuclear radiation” concept, question 15 and 86 % (radioactivity uses, question 14 in open-ended questions whereas in multiple choice questions the ratio of correct answers ranged from 5 % (concept definition and nuclear reactions, questions 21, 23 and 33 to 98 % (sample of concept, question 20. Students hold misconceptions on the radioactivity, warning picture, nuclear power plant (questions 1, 13, and 16; isotopes (question 4; natural and artificial nucleus reaction (question 6; age of the rocks (question 8; atomic bomb (question 10; hydrogen bomb (question 11 and core irradiation (question 15.

  10. Hydrologic Science and Satellite Measurements of Surface Water (Invited)

    Science.gov (United States)

    Alsdorf, D. E.; Mognard, N. M.; Lettenmaier, D. P.

    2010-12-01

    While significant advances continue to be made for satellite measurements of surface waters, important science and application opportunities remain. Examples include the following: (1) Our current methods of measuring floodwater dynamics are either sparsely distributed or temporally inadequate. As an example, flood depths are measured by using high water marks, which capture only the peak of the flood wave, not its temporal variability. (2) Discharge is well measured at individual points along stream networks using in-situ gauges, but these do not capture within-reach hydraulic variability such as the water surface slope changes on the rising and falling limbs of flood waves. (3) Just a 1.0 mm/day error in ET over the Congo Basin translates to a 35,000 m3/s discharge error. Knowing the discharge of the Congo River and its many tributaries should significantly improve our understanding of the water balance throughout the basin. The Congo is exemplary of many other basins around the globe. (4) Arctic hydrology is punctuated by millions of unmeasured lakes. Globally, there might be as many as 30 million lakes larger than a hectare. Storage changes in these lakes are nearly unknown, but in the Arctic such changes are likely an indication of global warming. (5) Well over 100 rivers cross international boundaries, yet the sharing of water data is poor. Overcoming this helps to better manage the entire river basin while also providing a better assessment of potential water related disasters. The Surface Water and Ocean Topography (SWOT, http://swot.jpl.nasa.gov/) mission is designed to meet these needs by providing global measurements of surface water hydrodynamics. SWOT will allow estimates of discharge in rivers wider than 100m (50m goal) and storage changes in water bodies larger than 250m by 250m (and likely as small as one hectare).

  11. Molecular metal catalysts on supports: organometallic chemistry meets surface science.

    Science.gov (United States)

    Serna, Pedro; Gates, Bruce C

    2014-08-19

    -support bonding and structure, which identify the supports as ligands with electron-donor properties that influence reactivity and catalysis. Each of the catalyst design variables has been varied independently, illustrated by mononuclear and tetranuclear iridium on zeolite HY and on MgO and by isostructural rhodium and iridium (diethylene or dicarbonyl) complexes on these supports. The data provide examples resolving the roles of the catalyst design variables and place the catalysis science on a firm foundation of organometallic chemistry linked with surface science. Supported molecular catalysts offer the advantages of characterization in the absence of solvents and with surface-science methods that do not require ultrahigh vacuum. Families of supported metal complexes have been made by replacement of ligands with others from the gas phase. Spectroscopically identified catalytic reaction intermediates help to elucidate catalyst performance and guide design. The methods are illustrated for supported complexes and clusters of rhodium, iridium, osmium, and gold used to catalyze reactions of small molecules that facilitate identification of the ligands present during catalysis: alkene dimerization and hydrogenation, H-D exchange in the reaction of H2 with D2, and CO oxidation. The approach is illustrated with the discovery of a highly active and selective MgO-supported rhodium carbonyl dimer catalyst for hydrogenation of 1,3-butadiene to give butenes.

  12. Evaluation of hydrogen and oxygen impurity levels on silicon surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Kenny, M J; Wielunski, L S; Netterfield, R P; Martin, P J; Leistner, A [Commonwealth Scientific and Industrial Research Organisation (CSIRO), Lindfield, NSW (Australia). Div. of Applied Physics

    1997-12-31

    This paper reports on surface analytical techniques used to quantify surface concentrations of impurities such as oxygen and hydrogen. The following analytical techniques were used: Rutherford and Backscattering, elastic recoil detection, time-of-flight SIMS, spectroscopic ellipsometry, x-ray photoelectron spectroscopy. The results have shown a spread in thickness of oxide layer, ranging from unmeasurable to 1.6 nm. The data must be considered as preliminary at this stage, but give some insight into the suitability of the techniques and a general idea of the significance of impurities at the monolayer level. These measurements have been carried out on a small number of silicon surfaces both semiconductor grade <111> crystalline material and silicon which has been used in sphere fabrication. 5 refs., 1 fig.

  13. Evaluation of hydrogen and oxygen impurity levels on silicon surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Kenny, M.J.; Wielunski, L.S.; Netterfield, R.P.; Martin, P.J.; Leistner, A. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), Lindfield, NSW (Australia). Div. of Applied Physics

    1996-12-31

    This paper reports on surface analytical techniques used to quantify surface concentrations of impurities such as oxygen and hydrogen. The following analytical techniques were used: Rutherford and Backscattering, elastic recoil detection, time-of-flight SIMS, spectroscopic ellipsometry, x-ray photoelectron spectroscopy. The results have shown a spread in thickness of oxide layer, ranging from unmeasurable to 1.6 nm. The data must be considered as preliminary at this stage, but give some insight into the suitability of the techniques and a general idea of the significance of impurities at the monolayer level. These measurements have been carried out on a small number of silicon surfaces both semiconductor grade <111> crystalline material and silicon which has been used in sphere fabrication. 5 refs., 1 fig.

  14. Surface science and model catalysis with ionic liquid-modified materials.

    Science.gov (United States)

    Steinrück, H-P; Libuda, J; Wasserscheid, P; Cremer, T; Kolbeck, C; Laurin, M; Maier, F; Sobota, M; Schulz, P S; Stark, M

    2011-06-17

    Materials making use of thin ionic liquid (IL) films as support-modifying functional layer open up a variety of new possibilities in heterogeneous catalysis, which range from the tailoring of gas-surface interactions to the immobilization of molecularly defined reactive sites. The present report reviews recent progress towards an understanding of "supported ionic liquid phase (SILP)" and "solid catalysts with ionic liquid layer (SCILL)" materials at the microscopic level, using a surface science and model catalysis type of approach. Thin film IL systems can be prepared not only ex-situ, but also in-situ under ultrahigh vacuum (UHV) conditions using atomically well-defined surfaces as substrates, for example by physical vapor deposition (PVD). Due to their low vapor pressure, these systems can be studied in UHV using the full spectrum of surface science techniques. We discuss general strategies and considerations of this approach and exemplify the information available from complementary methods, specifically photoelectron spectroscopy and surface vibrational spectroscopy. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Trace-level mercury removal from surface water

    International Nuclear Information System (INIS)

    Klasson, K.T.; Bostick, D.T.

    1998-01-01

    Many sorbents have been developed for the removal of mercury and heavy metals from waters; however, most of the data published thus far do not address the removal of mercury to the target levels represented in this project. The application to which these sorbents are targeted for use is the removal of mercury from microgram-per-liter levels to low nanogram-per-liter levels. Sorbents with thiouronium, thiol, amine, sulfur, and proprietary functional groups were selected for these studies. Mercury was successfully removed from surface water via adsorption onto Ionac SR-4 and Mersorb resins to levels below the target goal of 12 ng/L in batch studies. A thiol-based resin performed the best, indicating that over 200,000 volumes of water could be treated with one volume of resin. The cost of the resin is approximately $0.24 per 1,000 gal of water

  16. Sea level: measuring the bounding surfaces of the ocean

    Science.gov (United States)

    Tamisiea, Mark E.; Hughes, Chris W.; Williams, Simon D. P.; Bingley, Richard M.

    2014-01-01

    The practical need to understand sea level along the coasts, such as for safe navigation given the spatially variable tides, has resulted in tide gauge observations having the distinction of being some of the longest instrumental ocean records. Archives of these records, along with geological constraints, have allowed us to identify the century-scale rise in global sea level. Additional data sources, particularly satellite altimetry missions, have helped us to better identify the rates and causes of sea-level rise and the mechanisms leading to spatial variability in the observed rates. Analysis of all of the data reveals the need for long-term and stable observation systems to assess accurately the regional changes as well as to improve our ability to estimate future changes in sea level. While information from many scientific disciplines is needed to understand sea-level change, this review focuses on contributions from geodesy and the role of the ocean's bounding surfaces: the sea surface and the Earth's crust. PMID:25157196

  17. Sea level: measuring the bounding surfaces of the ocean.

    Science.gov (United States)

    Tamisiea, Mark E; Hughes, Chris W; Williams, Simon D P; Bingley, Richard M

    2014-09-28

    The practical need to understand sea level along the coasts, such as for safe navigation given the spatially variable tides, has resulted in tide gauge observations having the distinction of being some of the longest instrumental ocean records. Archives of these records, along with geological constraints, have allowed us to identify the century-scale rise in global sea level. Additional data sources, particularly satellite altimetry missions, have helped us to better identify the rates and causes of sea-level rise and the mechanisms leading to spatial variability in the observed rates. Analysis of all of the data reveals the need for long-term and stable observation systems to assess accurately the regional changes as well as to improve our ability to estimate future changes in sea level. While information from many scientific disciplines is needed to understand sea-level change, this review focuses on contributions from geodesy and the role of the ocean's bounding surfaces: the sea surface and the Earth's crust. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  18. Surface drainage in leveled land: Implication of slope

    Directory of Open Access Journals (Sweden)

    Antoniony S. Winkler

    Full Text Available ABSTRACT In the lowlands of Rio Grande do Sul, land leveling is mostly carried out with no slope for the purpose of rice production. In this environment, soils with a low hydraulic conductivity are predominant owing to the presence of a practically impermeable B-horizon near the surface. Land leveling leads to soil accommodation resulting in the formation of depressions where water accumulates after heavy rainfalls, subsequently leading to problems with crops implanted in succession to rice, such as soybeans. The objective of this research was to quantify the areas and volumes of water accumulation in soil as a function of the slope of land leveling. Five typical leveled lowland areas were studied as a part of this research. The original areas presented slopes of 0, 0.20, 0.25, 0.28 and 0.40%, which were used to generate new digital elevation models with slopes between 0 and 0.5%. These newly generated digital models were used to map the depressions with surface water storage. In conclusion, land leveling with slopes higher than 0.1% is recommended to minimize problems with superficial water storage in rice fields.

  19. EDITORIAL: Three decades of scanning tunnelling microscopy that changed the course of surface science Three decades of scanning tunnelling microscopy that changed the course of surface science

    Science.gov (United States)

    Ramachandra Rao, M. S.; Margaritondo, Giorgio

    2011-11-01

    Three decades ago, with a tiny tip of platinum, the scientific world saw the real space imaging of single atoms with unprecedented spatial resolution. This signalled the birth of one of the most versatile surface probes, based on the physics of quantum mechanical tunnelling: the scanning tunnelling microscope (STM). Invented in 1981 by Gerd Binnig and Heinrich Rohrer of IBM, Zurich, it led to their award of the 1986 Nobel Prize. Atoms, once speculated to be abstract entities used by theoreticians for mere calculations, can be seen to exist for real with the nano-eye of an STM tip that also gives real-space images of molecules and adsorbed complexes on surfaces. From a very fundamental perspective, the STM changed the course of surface science and engineering. STM also emerged as a powerful tool to study various fundamental phenomena relevant to the properties of surfaces in technological applications such as tribology, medical implants, catalysis, sensors and biology—besides elucidating the importance of local bonding geometries and defects, non-periodic structures and the co-existence of nano-scale phases. Atom-level probing, once considered a dream, has seen the light with the evolution of STM. An important off-shoot of STM was the atomic force microscope (AFM) for surface mapping of insulating samples. Then followed the development of a flurry of techniques under the general name of scanning probe microscopy (SPM). These techniques (STM, AFM, MFM, PFM etc) designed for atomic-scale-resolution imaging and spectroscopy, have led to brand new developments in surface analysis. All of these novel methods enabled researchers in recent years to image and analyse complex surfaces on microscopic and nanoscopic scales. All of them utilize a small probe for sensing the surface. The invention of AFM by Gerd Binnig, Calvin Quate and Christopher Gerber opened up new opportunities for characterization of a variety of materials, and various industrial applications could be

  20. Mineral Surface Reactivity in teaching of Science Materials

    Science.gov (United States)

    Del Hoyo Martínez, Carmen

    2013-04-01

    In the last fifty years, science materials issues has required the study of air pollution, water and soil to prevent and remedy the adverse effects of waste originating from anthropogenic activity and the development of new energies and new materials. The teaching of this discipline has been marked by lectures on general lines, materials, disciplines, who explained biased objects of reality, but often forgot the task of reconstruction and integration of such visions. Moving from that model, otherwise quite static, to a dynamic relational model, would in our view, a real revolution in education. This means taking a systematic approach to complex both in interpreting reality and in favor when learning. Children relationships are as important or more than single objects, and it is to discover fundamental organizational principles of phenomena we seek to interpret or in other words, find the pattern that connects. Thus, we must work on relationships and also take into account the relation between the observer and the observed. Educate about relationships means that studies should always be considered within a framework of probabilities, not absolute certainties. This model of systemic thinking, dealing with complexity, is a possibility to bring coherence to our educational work, because the complexity is not taught, complexity is live, so that complex thinking is extended (and fed) in a form educate complex. It is the task of teaching to help people move from level to level of decision reviews. This means that systems thinking should be extended in a local action, action that engages the individual and the environment. Science Materials has emerged as a discipline of free choice for pupils attending chemical engineering which has been assigned 6.0 credits. The chemical engineer's professional profile within the current framework is defined as a professional knowledge as a specialization technical / functional, working in a learning organization and the formation of

  1. Hydrogenation of nitriles on a well-characterized nickel surface: From surface science studies to liquid phase catalytic activity measurements

    Energy Technology Data Exchange (ETDEWEB)

    Gardin, Denis Emmanuel [Univ. of California, Berkeley, CA (United States)

    1993-12-01

    Nitrile hydrogenation is the most commonly used method for preparing diverse amines. This thesis is aimed at the mechanism and factors affecting the performance of Ni-based catalysts in nitrile hydrogenations. Surface science techniques are used to study bonding of nitriles and amines to a Ni(111) surface and to identify surface intermediates. Liquid-phase hydrogenations of cyclohexene and 1-hexene on a Pt foil were carried out successfully. Finally, knowledge about the surface structure, surface chemical bond, dynamics of surface atoms (diffusion, growth), and reactivity of metal surfaces from solid-gas interface studies, is discussed.

  2. Surface physics of materials materials science and technology

    CERN Document Server

    Blakely, J M

    2013-01-01

    Surface Physics of Materials presents accounts of the physical properties of solid surfaces. The book contains selected articles that deal with research emphasizing surface properties rather than experimental techniques in the field of surface physics. Topics discussed include transport of matter at surfaces; interaction of atoms and molecules with surfaces; chemical analysis of surfaces; and adhesion and friction. Research workers, teachers and graduate students in surface physics, and materials scientist will find the book highly useful.

  3. Sea Surface Height, Absolute, Aviso, 0.25 degrees, Global, Science Quality

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Aviso Absolute Sea Surface Height is the Sea Surface Height Deviation plus the long term mean dynamic height. This is Science Quality data.

  4. Optimized surface-slab excited-state muffin-tin potential and surface core level shifts

    International Nuclear Information System (INIS)

    Rundgren, J.

    2003-01-01

    An optimized muffin-tin (MT) potential for surface slabs with preassigned surface core-level shifts (SCLS's) is presented. By using the MT radii as adjustable parameters the model is able to conserve the definition of the SCLS with respect to the bulk and concurrently to generate a potential that is continuous at the MT radii. The model is conceived for elastic electron scattering in a surface slab with exchange-correlation interaction described by the local density approximation. The model employs two data bases for the self-energy of the signal electron (after Hedin and Lundqvist or Sernelius). The potential model is discussed in detail with two surface structures Be(101-bar0), for which SCLS's are available, and Cu(111)p(2x2)Cs, in which the close-packed radii of the atoms are extremely different. It is considered plausible that tensor LEED based on an optimized MT potential can be used for determining SCLS's

  5. Ab initio surface core-level shifts and surface segregation energies

    DEFF Research Database (Denmark)

    Aldén, Magnus; Skriver, Hans Lomholt; Johansson, Börje

    1993-01-01

    We have calculated the surface core-level energy shifts of the 4d and 5d transition metals by means of local-density theory and a Green’s-function technique based on the linear muffin-tin orbitals method. Final-state effects are included by treating the core-ionized atom as an impurity located in...

  6. Staying in the science stream: patterns of participation in A-level science subjects in the UK.

    OpenAIRE

    Smith, Emma

    2011-01-01

    This paper describes patterns of participation and attainment in A-level physics, chemistry and biology from 1961 to 2009. The A-level has long been seen as an important gateway qualification for higher level study, particularly in the sciences. This long term overview examines how recruitment to these three subjects has changed in the context of numerous policies and initiatives that seek to retain more young people in the sciences. The results show that recruitment to the pure sciences has ...

  7. Science self-efficacy of African Americans enrolled in freshman level physical science courses in two historically black institutions

    Science.gov (United States)

    Prihoda, Belinda Ann

    2011-12-01

    Science education must be a priority for citizens to function and be productive in a global, technological society. African Americans receive fewer science degrees in proportion to the Caucasian population. The primary purposes of this study were to determine the difference between the pretest and posttest science self-efficacy scores of African-American nonscience majors, the difference between the pretest and posttest science self-efficacy scores of African-American science majors, the relationship between science self-efficacy and course grade, the relationship between gender and science self-efficacy score, and the relationship between science self-efficacy score and course withdrawal. This study utilized a Likert survey instrument. All participants were enrolled in freshman level courses in the physical sciences at a historically black institution: a college or university. Participants completed the pretest survey within two weeks after the 12th class day of the semester. Initially, 458 participants completed the pretest survey. The posttest was administered within two weeks before the final exam. Only 245 participants completed the posttest survey. Results indicate that there is a difference in science self-efficacy of science majors and nonscience majors. There was no significant difference between the pretest and posttest science self-efficacy scores of African-American science majors and nonscience majors. There was no significant relationship between science self-efficacy and course grade, gender and science self-efficacy score, and course withdrawal and science self-efficacy score.

  8. Retrievable surface storage: interim storage of solidified high-level waste

    International Nuclear Information System (INIS)

    LaRiviere, J.R.; Nelson, D.C.

    1976-01-01

    Studies have been conducted on retrievable-surface-storage concepts for the interim storage of solidified high-level wastes. These studies have been reviewed by the Panel on Engineered Storage, convened by the Committee on Radioactive Waste Management of the National Research Council-National Academy of Sciences. The Panel has concluded that ''retrievable surface storage is an acceptable interim stage in a comprehensive system for managing high-level radioactive wastes.'' The scaled storage cask concept, which was recommended by the Panel on Engineered Storage, consists of placing a canister of waste inside a carbon-steel cask, which in turn is placed inside a thick concrete cylinder. The waste is cooled by natural convection air flow through an annulus between the cask and the inner wall of the concrete cylinder. The complete assembly is placed above ground in an outdoor storage area

  9. Materials Science of High-Level Nuclear Waste Immobilization

    International Nuclear Information System (INIS)

    Weber, William J.; Navrotsky, Alexandra; Stefanovsky, S. V.; Vance, E. R.; Vernaz, Etienne Y.

    2009-01-01

    With the increasing demand for the development of more nuclear power comes the responsibility to address the technical challenges of immobilizing high-level nuclear wastes in stable solid forms for interim storage or disposition in geologic repositories. The immobilization of high-level nuclear wastes has been an active area of research and development for over 50 years. Borosilicate glasses and complex ceramic composites have been developed to meet many technical challenges and current needs, although regulatory issues, which vary widely from country to country, have yet to be resolved. Cooperative international programs to develop advanced proliferation-resistant nuclear technologies to close the nuclear fuel cycle and increase the efficiency of nuclear energy production might create new separation waste streams that could demand new concepts and materials for nuclear waste immobilization. This article reviews the current state-of-the-art understanding regarding the materials science of glasses and ceramics for the immobilization of high-level nuclear waste and excess nuclear materials and discusses approaches to address new waste streams

  10. Internship training in computer science: Exploring student satisfaction levels.

    Science.gov (United States)

    Jaradat, Ghaith M

    2017-08-01

    The requirement of employability in the job market prompted universities to conduct internship training as part of their study plans. There is a need to train students on important academic and professional skills related to the workplace with an IT component. This article describes a statistical study that measures satisfaction levels among students in the faculty of Information Technology and Computer Science in Jordan. The objective of this study is to explore factors that influence student satisfaction with regards to enrolling in an internship training program. The study was conducted to gather student perceptions, opinions, preferences and satisfaction levels related to the program. Data were collected via a mixed method survey (surveys and interviews) from student-respondents. The survey collects demographic and background information from students, including their perception of faculty performance in the training poised to prepare them for the job market. Findings from this study show that students expect internship training to improve their professional and personal skills as well as to increase their workplace-related satisfaction. It is concluded that improving the internship training is crucial among the students as it is expected to enrich their experiences, knowledge and skills in the personal and professional life. It is also expected to increase their level of confidence when it comes to exploring their future job opportunities in the Jordanian market. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. 3S'83 Symposium on surface science. Contributions

    International Nuclear Information System (INIS)

    Braun, P.; Betz, G.; Husinsky, W.; Soellner, E.; Stoeri, H.; Varga, P.

    1983-01-01

    This symposium included the topics: electronic structure; ion-surface-interaction; surface structure; adsorption and reactivity; surface analysis; 60 papers were presented, only part of which pertain to INIS. (G.Q.)

  12. 52nd colloid and surface science symposium. Proceedings volume

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, E.L. Jr.; Corbett, H.G.

    1978-05-01

    Abstracts are presented under the headings: cell/surface interactions, surface properties and reactions of catalysts, solution chemistry of surfactants, dynamic systems, microorganism/surface interactions, gas-solid interactions, biological surfaces, solid sorbents, lung surfactant and intestinal absorption, pigments, and liquid systems. (DLC)

  13. A Multi-Level Systems Perspective for the Science of Team Science

    Science.gov (United States)

    Börner, Katy; Contractor, Noshir; Falk-Krzesinski, Holly J.; Fiore, Stephen M.; Hall, Kara L.; Keyton, Joann; Spring, Bonnie; Stokols, Daniel; Trochim, William; Uzzi, Brian

    2012-01-01

    This Commentary describes recent research progress and professional developments in the study of scientific teamwork, an area of inquiry termed the “science of team science” (SciTS, pronounced “sahyts”). It proposes a systems perspective that incorporates a mixed-methods approach to SciTS that is commensurate with the conceptual, methodological, and translational complexities addressed within the SciTS field. The theoretically grounded and practically useful framework is intended to integrate existing and future lines of SciTS research to facilitate the field’s evolution as it addresses key challenges spanning macro, meso, and micro levels of analysis. PMID:20844283

  14. Surface-Level Diversity and Decision-Making in Groups: When Does Deep-Level Similarity Help?

    OpenAIRE

    2006-01-01

    Abstract We examined how surface-level diversity (based on race) and deep-level similarities influenced three-person decision-making groups on a hidden-profile task. Surface-level homogeneous groups perceived their information to be less unique and spent less time on the task than surface-level diverse groups. When the groups were given the opportunity to learn about their deep-level similarities prior to t...

  15. A comparison of the Web of Science with publication-level classification systems of science

    Energy Technology Data Exchange (ETDEWEB)

    Perianes-Rodriguez, A.; Ruiz-Castillo, J.

    2016-07-01

    In this paper we propose a new criterion for choosing between a pair of classification systems of science that assign publications (or journals) to a set of scientific fields. Consider the standard normalization procedure in which field mean citations are used as normalization factors. We recommend system A over system B whenever the standard normalization procedure based on A performs better than the when it is based on B. Since the evaluation can be made in terms of either system, the performance assessment requires a double test. In addition, since the assessment of two normalization procedures would be generally biased in favor of the one based on the classification system used for evaluation purposes, ideally a pair of classification systems must be compared using a third, independent classification system for evaluation purposes. We illustrate this strategy by comparing a Web of Science journal-level classification system, consisting of 236 journal subject categories, with two publication-level algorithmically constructed classification systems consisting of 1,363 (G6) and 5,119 (G8) clusters. There are two main findings. (1) The G8 system is found to dominate the G6 system. Therefore, when we have a choice between two classification systems at different granularity levels, we should use the system at the higher level because it typically exhibits a better standard normalization performance. (2) The G8 system and the Web of Science (WoS) journal-level system are found to be non-comparable. Nevertheless, the G8-normalization procedure performs better using the WoS system for evaluation purposes than the WoS-normalization procedure using the G8 system for evaluation purposes. Furthermore, when we use the G6 system for evaluation purposes, the G8-normalization procedure performs better than the WoS-normalization procedure. We conclude that algorithmically constructed classification systems constitute a credible alternative to the WoS system and, by extension, to

  16. Investigation of Primary Education Second Level Students' Motivations toward Science Learning in Terms of Various Factors

    Science.gov (United States)

    Sert Çibik, Ayse

    2014-01-01

    The purpose of this research was to investigate the primary education second level students' motivations towards science learning in terms of various factors. Within the research, the variation of the total motivational scores in science learning according to the gender, class, socio-economic levels, success in science-technology course and…

  17. Desert Research and Technology Studies (DRATS) 2010 Science Operations: Operational Approaches and Lessons Learned for Managing Science during Human Planetary Surface Missions

    Science.gov (United States)

    Eppler, Dean; Adams, Byron; Archer, Doug; Baiden, Greg; Brown, Adrian; Carey, William; Cohen, Barbara; Condit, Chris; Evans, Cindy; Fortezzo, Corey; hide

    2012-01-01

    Desert Research and Technology Studies (Desert RATS) is a multi-year series of hardware and operations tests carried out annually in the high desert of Arizona on the San Francisco Volcanic Field. These activities are designed to exercise planetary surface hardware and operations in conditions where long-distance, multi-day roving is achievable, and they allow NASA to evaluate different mission concepts and approaches in an environment less costly and more forgiving than space.The results from the RATS tests allows election of potential operational approaches to planetary surface exploration prior to making commitments to specific flight and mission hardware development. In previous RATS operations, the Science Support Room has operated largely in an advisory role, an approach that was driven by the need to provide a loose science mission framework that would underpin the engineering tests. However, the extensive nature of the traverse operations for 2010 expanded the role of the science operations and tested specific operational approaches. Science mission operations approaches from the Apollo and Mars-Phoenix missions were merged to become the baseline for this test. Six days of traverse operations were conducted during each week of the 2-week test, with three traverse days each week conducted with voice and data communications continuously available, and three traverse days conducted with only two 1-hour communications periods per day. Within this framework, the team evaluated integrated science operations management using real-time, tactical science operations to oversee daily crew activities, and strategic level evaluations of science data and daily traverse results during a post-traverse planning shift. During continuous communications, both tactical and strategic teams were employed. On days when communications were reduced to only two communications periods per day, only a strategic team was employed. The Science Operations Team found that, if

  18. Role of surface studies in science and technology

    Energy Technology Data Exchange (ETDEWEB)

    Karkhanavala, M D [Bhabha Atomic Research Centre, Bombay (India). Chemistry Div.

    1977-01-01

    Reactivity of solids is influenced by the surface properties such as structure, dislocations and composition. Corrosion and erosion are essentially surface phenomena. Surface studies, therefore, assume importance in prevention and minimization of corrosion and erosion. Discussion is illustrated with examples drawn from the field of nuclear power reactor technology.

  19. A-Level Science--What Value Practical?

    Science.gov (United States)

    McCune, Roger

    2014-01-01

    The Qualifications Regulator in England (Ofqual) has decided that with the implementation of revised (linear) science specifications, first teaching from September 2015, the assessment of practical skills will not contribute to the overall qualification grade. This could have significant implications for post-16 science teaching. The decision was…

  20. Special Project Examination in Integrated Science - Ordinary Level.

    Science.gov (United States)

    Wimpenny, David

    A science achievement test for the General Certificate of Education (GCE, England) was developed for students enrolled in the curriculum of the Schools Council Integrated Science Project. This document contains discussions of the testing program and a copy of the 1973 test. After an overview of the curriculum project and issues related to…

  1. Communicating Ocean Science at the Lower-Division Level

    Science.gov (United States)

    Coopersmith, A.

    2011-12-01

    Pacific Ocean Literacy for Youth, Publics, Professionals, and Scientists (POLYPPS) is an NSF-funded collaboration between the University of Hawai`i and the Center for Ocean Science Education Excellence (COSEE) - California, which is based at the Lawrence Hall of Science, University of California - Berkeley. One of the objectives of this project is to instutionalize ocean science communications courses at colleges and universities in Hawai`i. Although the focus of most of these communications courses has been on training graduate students and scientists, lower-division students interested in the ocean sciences are finding this background helpful. At the University of Hawai`i Maui College there are several marine science courses and certificate programs that require students to interact with the public through internships, research assistantships, and course-related service-learning projects. Oceanography 270, Communicating Ocean Science, is now offered to meet the needs of these students who engage with the public in informal educational settings. Other students who enroll in this course have a general interest in the marine environment and are considering careers in K-12 formal education. This course gives this group of students an opportunity to explore formal education by assisting classroom teachers and preparing and presenting problem-based, hands-on, inquiry activities. Employers at marine-related businesses and in the tourist industry have welcomed this course with a focus on communication skills and indicate that they prefer to hire local people with strong backgrounds in marine and natural sciences. A basic premise of POLYPPS is that science education must draw not only from the latest advances in science and technology but also from the cultural contexts in which the learners are embedded and that this will achieve increased understanding and stewardship of ocean environments. Students in Oceanography 270 integrate traditional Hawaiian knowledge into their

  2. Maximum surface level and temperature histories for Hanford waste tanks

    International Nuclear Information System (INIS)

    Flanagan, B.D.; Ha, N.D.; Huisingh, J.S.

    1994-01-01

    Radioactive defense waste resulting from the chemical processing of spent nuclear fuel has been accumulating at the Hanford Site since 1944. This waste is stored in underground waste-storage tanks. The Hanford Site Tank Farm Facilities Interim Safety Basis (ISB) provides a ready reference to the safety envelope for applicable tank farm facilities and installations. During preparation of the ISB, tank structural integrity concerns were identified as a key element in defining the safety envelope. These concerns, along with several deficiencies in the technical bases associated with the structural integrity issues and the corresponding operational limits/controls specified for conduct of normal tank farm operations are documented in the ISB. Consequently, a plan was initiated to upgrade the safety envelope technical bases by conducting Accelerated Safety Analyses-Phase 1 (ASA-Phase 1) sensitivity studies and additional structural evaluations. The purpose of this report is to facilitate the ASA-Phase 1 studies and future analyses of the single-shell tanks (SSTs) and double-shell tanks (DSTs) by compiling a quantitative summary of some of the past operating conditions the tanks have experienced during their existence. This report documents the available summaries of recorded maximum surface levels and maximum waste temperatures and references other sources for more specific data

  3. Experimental innovations in surface science a guide to practical laboratory methods and instruments

    CERN Document Server

    Yates, John T

    2015-01-01

    This book is a new edition of a classic text on experimental methods and instruments in surface science. It offers practical insight useful to chemists, physicists, and materials scientists working in experimental surface science. This enlarged second edition contains almost 300 descriptions of experimental methods. The more than 50 active areas with individual scientific and measurement concepts and activities relevant to each area are presented in this book. The key areas covered are: Vacuum System Technology, Mechanical Fabrication Techniques, Measurement Methods, Thermal Control, Delivery of Adsorbates to Surfaces, UHV Windows, Surface Preparation Methods, High Area Solids, Safety. The book is written for researchers and graduate students.

  4. Sea Surface Height Deviation, Aviso, 0.25 degrees, Global, Science Quality

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Aviso Sea Surface Height Deviation is the deviation from the mean geoid as measured from 1993 - 1995. This is Science Quality data.

  5. Is This the End of the English Tradition of Practical A-Level Science?

    Science.gov (United States)

    Carter, Ian

    2014-01-01

    From September 2015, schools in England will be teaching new A-level science specifications that have been developed by examination boards to encompass new higher levels of demand developed by the Department for Education. Integral to these new specifications is a radical change to the contribution of practical science to the A-level grade of the…

  6. The Science Advancement through Group Engagement Program: Leveling the Playing Field and Increasing Retention in Science

    Science.gov (United States)

    Hall, Donna M.; Curtin-Soydan, Amanda J.; Canelas, Dorian A.

    2014-01-01

    How can colleges and universities keep an open gateway to the science disciplines for the least experienced first-year science students while also maintaining high standards that challenge the students with the strongest possible high school backgrounds? The Science Advancement through Group Engagement (SAGE) project targets cohorts of less…

  7. Organizational health and the achievement level of students in science at the secondary-level schools in Sri Lanka

    Science.gov (United States)

    Pakkeer-Jaufar, Pakkeer Cadermohideen

    This study sought to identify those organizational health factors that might have overriding influence on the achievement level of students in science in Sri Lankan secondary schools. This study involved 752 students, 33 science teachers, and 10 principals from two different districts, Ampara and Colombo, in Sri Lanka. Ten Tamil medium, secondary level, public schools were selected to participate in this study. Data were collected using four types of instruments: a questionnaire for pupils; interview schedules for science teachers and principals; checklists for classroom/school facilities, science laboratory facilities, and science practicals; and a science achievement test. The analysis focused on the collective perceptions of students, science teachers, and principals. Regression and path analyses were used as major analysis techniques, and the qualitative data provided by science teachers and principals were considered for a crosschecking of the quantitative inferences. The researcher found teacher affiliation, academic emphasis, and instructional leadership of the principal, in descending order, were the overriding influential factors on the achievement level of students in science in Sri Lankan secondary schools. At the same time a similar descending order was found in their mean values and qualities. The researcher concluded that increasing the quality of the organizational health factors in Sri Lankan secondary schools would result in improved better achievement in science. The findings further indicate that instructional leadership of the principal had both direct and indirect effects on students' achievement in science when academic emphasis and teacher affiliation were taken into account. In addition, the resource support of the principal did not make any difference in students' science achievement and the findings stress the availability of the resources for individual students instead of assuming the general facilities of the school are available to all

  8. Proportional Reasoning Ability and Concepts of Scale: Surface Area to Volume Relationships in Science

    Science.gov (United States)

    Taylor, Amy; Jones, Gail

    2009-01-01

    The "National Science Education Standards" emphasise teaching unifying concepts and processes such as basic functions of living organisms, the living environment, and scale. Scale influences science processes and phenomena across the domains. One of the big ideas of scale is that of surface area to volume. This study explored whether or not there…

  9. Staying in the Science Stream: Patterns of Participation in A-Level Science Subjects in the UK

    Science.gov (United States)

    Smith, Emma

    2011-01-01

    This paper describes patterns of participation and attainment in A-level physics, chemistry and biology from 1961 to 2009. The A level has long been seen as an important gateway qualification for higher level study, particularly in the sciences. This long-term overview examines how recruitment to these three subjects has changed in the context of…

  10. Experimental study on source efficiencies for estimating surface contamination level

    International Nuclear Information System (INIS)

    Ichiji, Takeshi; Ogino, Haruyuki

    2008-01-01

    Source efficiency was measured experimentally for various materials, such as metals, nonmetals, flooring materials, sheet materials and other materials, contaminated by alpha and beta emitter radioactive nuclides. Five nuclides, 147 Pm, 60 Co, 137 Cs, 204 Tl and 90 Sr- 90 Y, were used as the beta emitters, and one nuclide 241 Am was used as the alpha emitter. The test samples were prepared by placing drops of the radioactive standardized solutions uniformly on the various materials using an automatic quantitative dispenser system from Musashi Engineering, Inc. After placing drops of the radioactive standardized solutions, the test materials were allowed to dry for more than 12 hours in a draft chamber with a hood. The radioactivity of each test material was about 30 Bq. Beta rays or alpha rays from the test materials were measured with a 2-pi gas flow proportional counter from Aloka Co., Ltd. The source efficiencies of the metals, nonmetals and sheet materials were higher than 0.5 in the case of contamination by the 137 Cs, 204 Tl and 90 Sr- 90 Y radioactive standardized solutions, higher than 0.4 in the case of contamination by the 60 Co radioactive standardized solution, and higher than 0.25 in the case of contamination by the alpha emitter the 241 Am radioactive standardized solution. These values were higher than those given in Japanese Industrial Standards (JIS) documents. In contrast, the source efficiencies of some permeable materials were lower than those given in JIS documents, because source efficiency varies depending on whether the materials or radioactive sources are wet or dry. This study provides basic data on source efficiency, which is useful for estimating the surface contamination level of materials. (author)

  11. CalfScience: Extension Education at Many Levels

    Science.gov (United States)

    Moore, Dale A.; Tellessen, Kathlyn; Sischo, William M.

    2010-01-01

    The issue of antimicrobial resistance in food animal agriculture was addressed by conducting clinical trials to assess alternatives to antimicrobials in dairy calf-raising and developing outreach to three different audiences. Current research was integrated into Extension programs for calf-raisers, animal science and veterinary students, and food…

  12. Density functional theory in surface science and heterogeneous catalysis

    DEFF Research Database (Denmark)

    Nørskov, Jens Kehlet; Scheffler, M.; Toulhoat, H.

    2006-01-01

    Solid surfaces are used extensively as catalysts throughout the chemical industry, in the energy sector, and in environmental protection. Recently, density functional theory has started providing new insight into the atomic-scale mechanisms of heterogeneous catalysis, helping to interpret the large...

  13. Surface science studies of ethene containing model interstellar ices

    Science.gov (United States)

    Puletti, F.; Whelan, M.; Brown, W. A.

    2011-05-01

    The formation of saturated hydrocarbons in the interstellar medium (ISM) is difficult to explain only by taking into account gas phase reactions. This is mostly due to the fact that carbonium ions only react with H_2 to make unsaturated hydrocarbons, and hence no viable route to saturated hydrocarbons has been postulated to date. It is therefore likely that saturation processes occur via surface reactions that take place on interstellar dust grains. One of the species of interest in this family of reactions is C_2H_4 (ethene) which is an intermediate in several molecular formation routes (e.g. C_2H_2 → C_2H_6). To help to understand some of the surface processes involving ethene, a study of ethene deposited on a dust grain analogue surface (highly oriented pyrolytic graphite) held under ultra-high vacuum at 20 K has been performed. The adsorption and desorption of ethene has been studied both in water-free and water-dominated model interstellar ices. A combination of temperature programmed desorption (TPD) and reflection absorption infrared spectroscopy (RAIRS) have been used to identify the adsorbed and trapped species and to determine the kinetics of the desorption processes. In all cases, ethene is found to physisorb on the carbonaceous surface. As expected water has a very strong influence on the desorption of ethene, as previously observed for other model interstellar ice systems.

  14. The influence of lithology on surface water sources | Science ...

    Science.gov (United States)

    Understanding the temporal and spatial variability of surface water sources within a basin is vital to our ability to manage the impacts of climate variability and land cover change. Water stable isotopes can be used as a tool to determine geographic and seasonal sources of water at the basin scale. Previous studies in the Coastal Range of Oregon reported that the variation in the isotopic signatures of surface water does not conform to the commonly observed “rainout effect”, which exhibits a trend of increasing isotopic depletion with rising elevation. The primary purpose of this research is to investigate the mechanisms governing seasonal and spatial variations in the isotopic signature of surface waters within the Marys River Basin, located in the leeward side of the Oregon Coastal Range. Surface water and precipitation samples were collected every 2-3 weeks for isotopic analysis of δ18O and δ2H for one year. Results indicate a significant difference in isotopic signature between watersheds underlain by basalt and sandstone. The degree of separation was the most distinct during the summer when low flows reflect deeper groundwater sources, whereas isotopic signatures during the rainy season (fall and winter) showed a greater degree of similarity between the two lithologies. This indicates that baseflow within streams drained by sandstone versus basalt is being supplied from two distinctly separate water sources. In addition, Marys River flow at the outle

  15. The effects of student-level and classroom-level factors on elementary students' science achievement in five countries

    Science.gov (United States)

    Kaya, Sibel

    The interest in raising levels of achievement in math and science has led to a focus on investigating the factors that shape achievement in these subjects (Lamb & Fullarton, 2002) as well as understanding how these factors operate across countries (Baker, Fabrega, Galindo, & Mishook, 2004). The current study examined the individual student factors and classroom factors on fourth grade science achievement within and across five countries. Guided by the previous school learning models, the elements of students' science learning were categorized as student-level and classroom-level factors. The student-level factors included gender, self-confidence in science, and home resources. The classroom-level factors included teacher characteristics, instructional variables and classroom composition. Results for the United States and four other countries, Singapore, Japan, Australia, and Scotland were reported. Multilevel effects of student and classroom variables were examined through Hierarchical Linear Modeling (HLM) using the Trends in International Mathematics and Science Study (TIMSS) 2003 fourth grade dataset. The outcome variable was the TIMSS 2003 science score. Overall, the results of this study showed that selected student background characteristics were consistently related to elementary science achievement in countries investigated. At the student-level, higher levels of home resources and self-confidence and at the classroom-level, higher levels of class mean home resources yielded higher science scores on the TIMSS 2003. In general, teacher and instructional variables were minimally related to science achievement. There was evidence of positive effects of teacher support in the U.S. and Singapore. The emphasis on science inquiry was positively related to science achievement in Singapore and negatively related in the U.S. and Australia. Experimental studies that investigate the impacts of teacher and instructional factors on elementary science achievement are

  16. Modelling episodic acidification of surface waters: the state of science.

    Science.gov (United States)

    Eshleman, K N; Wigington, P J; Davies, T D; Tranter, M

    1992-01-01

    Field studies of chemical changes in surface waters associated with rainfall and snowmelt events have provided evidence of episodic acidification of lakes and streams in Europe and North America. Modelling these chemical changes is particularly challenging because of the variability associated with hydrological transport and chemical transformation processes in catchments. This paper provides a review of mathematical models that have been applied to the problem of episodic acidification. Several empirical approaches, including regression models, mixing models and time series models, support a strong hydrological interpretation of episodic acidification. Regional application of several models has suggested that acidic episodes (in which the acid neutralizing capacity becomes negative) are relatively common in surface waters in several regions of the US that receive acid deposition. Results from physically based models have suggested a lack of understanding of hydrological flowpaths, hydraulic residence times and biogeochemical reactions, particularly those involving aluminum. The ability to better predict episodic chemical responses of surface waters is thus dependent upon elucidation of these and other physical and chemical processes.

  17. A Molecular-Level Account of the Antigenic Hantaviral Surface

    Directory of Open Access Journals (Sweden)

    Sai Li

    2016-05-01

    Full Text Available Hantaviruses, a geographically diverse group of zoonotic pathogens, initiate cell infection through the concerted action of Gn and Gc viral surface glycoproteins. Here, we describe the high-resolution crystal structure of the antigenic ectodomain of Gn from Puumala hantavirus (PUUV, a causative agent of hemorrhagic fever with renal syndrome. Fitting of PUUV Gn into an electron cryomicroscopy reconstruction of intact Gn-Gc spike complexes from the closely related but non-pathogenic Tula hantavirus localized Gn tetramers to the membrane-distal surface of the virion. The accuracy of the fitting was corroborated by epitope mapping and genetic analysis of available PUUV sequences. Interestingly, Gn exhibits greater non-synonymous sequence diversity than the less accessible Gc, supporting a role of the host humoral immune response in exerting selective pressure on the virus surface. The fold of PUUV Gn is likely to be widely conserved across hantaviruses.

  18. Surface science. Adhesion and friction in mesoscopic graphite contacts.

    Science.gov (United States)

    Koren, Elad; Lörtscher, Emanuel; Rawlings, Colin; Knoll, Armin W; Duerig, Urs

    2015-05-08

    The weak interlayer binding in two-dimensional layered materials such as graphite gives rise to poorly understood low-friction characteristics. Accurate measurements of the adhesion forces governing the overall mechanical stability have also remained elusive. We report on the direct mechanical measurement of line tension and friction forces acting in sheared mesoscale graphite structures. We show that the friction is fundamentally stochastic in nature and is attributable to the interaction between the incommensurate interface lattices. We also measured an adhesion energy of 0.227 ± 0.005 joules per square meter, in excellent agreement with theoretical models. In addition, bistable all-mechanical memory cell structures and rotational bearings have been realized by exploiting position locking, which is provided solely by the adhesion energy. Copyright © 2015, American Association for the Advancement of Science.

  19. Evaluation of the Levels of phthalate Ester Plasticizers in Surface ...

    African Journals Online (AJOL)

    ADOWIE PERE

    Gas chromatography (GC) coupled with mass ... Key words: phthalates, acid esters, plasticizers, Ethiope River, surface water, pollution ... waste and emissions arising from burning of refuse ... deepest inland waterways in Africa, is known for its ..... carbon nitride nanocomposites for the solid-phase extraction of phthalate ...

  20. The SMAP Level 4 Surface and Root-zone Soil Moisture (L4_SM) Product

    Science.gov (United States)

    Reichle, Rolf; Crow, Wade; Koster, Randal; Kimball, John

    2010-01-01

    The Soil Moisture Active and Passive (SMAP) mission is being developed by NASA for launch in 2013 as one of four first-tier missions recommended by the U.S. National Research Council Committee on Earth Science and Applications from Space in 2007. The primary science objectives of SMAP are to enhance understanding of land surface controls on the water, energy and carbon cycles, and to determine their linkages. Moreover, the high resolution soil moisture mapping provided by SMAP has practical applications in weather and seasonal climate prediction, agriculture, human health, drought and flood decision support. In this paper we describe the assimilation of SMAP observations for the generation of the planned SMAP Level 4 Surface and Root-zone Soil Moisture (L4_SM) product. The SMAP mission makes simultaneous active (radar) and passive (radiometer) measurements in the 1.26-1.43 GHz range (L-band) from a sun-synchronous low-earth orbit. Measurements will be obtained across a 1000 km wide swath using conical scanning at a constant incidence angle (40 deg). The radar resolution varies from 1-3 km over the outer 70% of the swath to about 30 km near the center of the swath. The radiometer resolution is 40 km across the entire swath. The radiometer measurements will allow high-accuracy but coarse resolution (40 km) measurements. The radar measurements will add significantly higher resolution information. The radar is however very sensitive to surface roughness and vegetation structure. The combination of the two measurements allows optimal blending of the advantages of each instrument. SMAP directly observes only surface soil moisture (in the top 5 cm of the soil column). Several of the key applications targeted by SMAP, however, require knowledge of root zone soil moisture (approximately top 1 m of the soil column), which is not directly measured by SMAP. The foremost objective of the SMAP L4_SM product is to fill this gap and provide estimates of root zone soil moisture

  1. Season Spotter: Using Citizen Science to Validate and Scale Plant Phenology from Near-Surface Remote Sensing

    Directory of Open Access Journals (Sweden)

    Margaret Kosmala

    2016-09-01

    Full Text Available The impact of a rapidly changing climate on the biosphere is an urgent area of research for mitigation policy and management. Plant phenology is a sensitive indicator of climate change and regulates the seasonality of carbon, water, and energy fluxes between the land surface and the climate system, making it an important tool for studying biosphere–atmosphere interactions. To monitor plant phenology at regional and continental scales, automated near-surface cameras are being increasingly used to supplement phenology data derived from satellite imagery and data from ground-based human observers. We used imagery from a network of phenology cameras in a citizen science project called Season Spotter to investigate whether information could be derived from these images beyond standard, color-based vegetation indices. We found that engaging citizen science volunteers resulted in useful science knowledge in three ways: first, volunteers were able to detect some, but not all, reproductive phenology events, connecting landscape-level measures with field-based measures. Second, volunteers successfully demarcated individual trees in landscape imagery, facilitating scaling of vegetation indices from organism to ecosystem. And third, volunteers’ data were used to validate phenology transition dates calculated from vegetation indices and to identify potential improvements to existing algorithms to enable better biological interpretation. As a result, the use of citizen science in combination with near-surface remote sensing of phenology can be used to link ground-based phenology observations to satellite sensor data for scaling and validation. Well-designed citizen science projects targeting improved data processing and validation of remote sensing imagery hold promise for providing the data needed to address grand challenges in environmental science and Earth observation.

  2. STS Observations of Landau Levels at Graphite Surfaces

    OpenAIRE

    Matsui, T.; Kambara, H.; Niimi, Y.; Tagami, K.; Tsukada, M.; Fukuyama, Hiroshi

    2004-01-01

    Scanning tunneling spectroscopy measurements were made on surfaces of two different kinds of graphite samples, Kish graphite and highly oriented pyrolytic graphite (HOPG), at very low temperatures and in high magnetic fields. We observed a series of peaks in the tunnel spectra, which grow with increasing field, both at positive and negative bias voltages. These are associated with Landau quantization of the quasi two-dimensional electrons and holes in graphite in magnetic fields perpendicular...

  3. CHEMICAL REACTIONS ON ADSORBING SURFACE: KINETIC LEVEL OF DESCRIPTION

    Directory of Open Access Journals (Sweden)

    P.P.Kostrobii

    2003-01-01

    Full Text Available Based on the effective Hubbard model we suggest a statistical description of reaction-diffusion processes for bimolecular chemical reactions of gas particles adsorbed on the metallic surface. The system of transport equations for description of particles diffusion as well as reactions is obtained. We carry out the analysis of the contributions of all physical processes to the formation of diffusion coefficients and chemical reactions constants.

  4. Intense positron beam and its application to surface science

    International Nuclear Information System (INIS)

    Ito, Y.; Hirose, M.; Kanazawa, I.; Sueoka, O.; Takamura, S.; Okada, S.

    1992-01-01

    Intense pulsed slow positron beam has been produced using the 100 MeV electron LINAC of JAERI · Tokai. In order to use the beam for surface studies such as positron diffraction and positron microscopy, it was transferred from the solenoid magnetic field to field free region and then was brightness-enhanced. The beam size was reduced from 10 mmφ (in the magnetic field) to 0.5 mmφ after two stages of re-moderation. Using the intense brightness-enhanced positron beam we have observed for the first time RHEPD (Reflection High-Energy Positron Diffraction) patterns. A design of re-emission positron microscopy is also described. (author)

  5. Building Surface Science Capacity to Serve the Automobile Industry in Southeastern Michigan, final report

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Weidian

    2013-09-27

    This project, “Building Surface Science Capacity to Serve the Automobile Industry in Southeastern Michigan” was carried out in two phases: (1) the 2009 – 2012 renovation of space in the new EMU Science Complex, which included the Surface Science Laboratory (SSL), a very vigorous research lab at EMU that carries on a variety of research projects to serve the auto and other industries in Michigan; and (2) the 2013 purchase of several pieces of equipment to further enhance the research capability of the SSL. The funding granted by the DoE was proposed to “renovate the space in the Science Complex to include SSL and purchase equipment for tribological and electrochemical impedance measurements in the lab, thus SSL will serve the auto and other industries in Michigan better.” We believe we have fully accomplished the mission.

  6. Structural dependence of the 5d-metal surface energies as deduced from surface core-level shift measurements

    International Nuclear Information System (INIS)

    Mrartensson, N.; Saalfeld, H.B.; Kuhlenbeck, H.; Neumann, M.

    1989-01-01

    Surface core-level shift measurements performed at the BESSY storage ring yield -0.41(2) eV for Os(0001) and 0.00(10) eV for Re(0001). An analysis of the surface shifts in the 5d transition series shows that the surface energy as a function of Z has a maximum at lower Z for the bcc phase than for the fcc-hcp phases, at W and between Re and Os, respectively

  7. The levels of edit. [technical writing in science

    Science.gov (United States)

    Vanburen, R.; Buehler, M. F.; Wallenbrock, D. (Editor)

    1976-01-01

    The editorial process is analyzed, and five levels of edit are identified. These levels represent cumulative combinations of nine types of edit: (1) coordination, (2) policy, (3) integrity, (4) screening, (5) copy clarification, (6) Mechanical Style, (7) Language, and (9) substantive. The levels and types of edit, although developed for specific use with external reports at the Jet Propulsion Laboratory, cover the general range of technical editing, especially as it applies to an in-house technical publications organization. Each type of edit is set forth in terms of groups of actions to be performed by the editor. The edit-level concept has enhanced understanding and communication among editors, authors, and publications managers concerning the specific editorial work to be done on each manuscript. It has also proved useful as a management tool for estimating and monitoring cost.

  8. GHRSST Level 4 DMI_OI Global Foundation Sea Surface Temperature Analysis (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis by the Danish...

  9. GHRSST Level 4 MUR North America Regional Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced as a retrospective dataset at the JPL Physical...

  10. GHRSST Level 4 OSPO Global Nighttime Foundation Sea Surface Temperature Analysis (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the Office of...

  11. GHRSST Level 4 AVHRR_AMSR_OI Global Blended Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) global Level 4 sea surface temperature analysis produced daily on a 0.25 degree grid at the NOAA...

  12. GHRSST Level 4 ODYSSEA Mediterranean Sea Regional Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at Ifremer/CERSAT...

  13. GHRSST Level 4 G1SST Global Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis by the JPL OurOcean...

  14. GHRSST Level 4 MW_OI Global Foundation Sea Surface Temperature analysis (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) global Level 4 sea surface temperature analysis produced daily on a 0.25 degree grid at Remote Sensing...

  15. GHRSST Level 4 K10_SST Global 1 meter Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the Naval...

  16. GHRSST Level 4 EUR Mediterranean Sea Regional Foundation Sea Surface Temperature Analysis (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily by Ifremer/CERSAT (France) using optimal...

  17. GHRSST Level 4 ODYSSEA Eastern Central Pacific Regional Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at Ifremer/CERSAT...

  18. GHRSST Level 4 ODYSSEA Global Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at Ifremer/CERSAT...

  19. GHRSST Level 4 OSPO Global Foundation Sea Surface Temperature Analysis (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the Office of...

  20. GHRSST Level 4 GAMSSA Global Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the Australian Bureau...

  1. GHRSST Level 4 RAMSSA Australian Regional Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the Australian Bureau...

  2. GHRSST Level 4 OSTIA Global Foundation Sea Surface Temperature Analysis (GDS versions 1 and 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the UK Met Office...

  3. Radioactivity levels in surface water of lakes around Izmir / Turkey

    International Nuclear Information System (INIS)

    Doyurum, S.; Turkozu, D. A.; Aslani, M. A. A.; Aytas, S.; Eral, M.; Kaygun, A. K.

    2006-01-01

    Radioactivity presents in surface continental waters is mainly due to the presence of radioactive elements in the earth's crust, other artificial radionuclides have appeared due to such human activities as nuclear power plants, nuclear weapons testing and manufacture and use of radioactive sources It is well known that natural radionuclides can be effective as tracers for the different processes controlling the distribution of elements among dissolved and particulate phases in aquatic systems. The detection of high radionuclide concentrations was proposed as a public health problem in several areas and consequently studies into the risks of radionuclides were started in the 2000s. Especially, these radioactive substances in groundwater are an unwanted and involuntary risk factor from natural sources, not artificial sources. These radioactive substances include uranium, radon found in uranium series, and other radioactive substances such as radium and gross alpha. Uranium present in rock, soil, and natural materials, and is found in small quantities in air, water, and food that people always contact. In this project, lake water samples were collected from three lakes around Izmir-Turkey. In surface lake water samples, pH, mV and conductivity values were measured and alkaline content was determined titrimetrically. The uranium concentrations in the lake water samples were measured using uranium analyzer. The radioactivity concentrations related to gross radium isotopes, gross-? and gross-? activities in the surface lake water were determined. The correlation among some parameters for water samples and concentrations of uranium, activity concentration of gross radium isotopes, gross alpha and gross beta radioactivity are also discussed

  4. FJ-2207 measuring instrument detection pipe surface a level of pollution method

    International Nuclear Information System (INIS)

    Wang Jiangong

    2010-01-01

    On the pipe surface contamination were detected α level of pollution is a frequently encountered dose-detection work. Because the pipeline surface arc, while the measuring probe for the plane, which for accurate measurement difficult. In this paper, on the FJ-2207-type pipe surface contamination measuring instrument measuring pollution levels in the α method was studied. Introduced the FJ-2207 measuring instrument detection pipe surface α pollution levels. Studied this measuring instrument on the same sources of surface, plane α level of radioactivity measured differences in the results obtained control of the apparatus when the direct measurement of the surface correction factor, and gives 32-216 specifications commonly used pipe direct measurement of the amendment factor. Convenient method, test results are reliable for the accurate measurement of pipe pollution levels in the surface of α as a reference and learning. (authors)

  5. Surface finishing and levelling of thermomechanically hardened rolled steel

    International Nuclear Information System (INIS)

    Grosval'd, V.G.; Bashchenko, A.P.; Grishkov, A.I.; Gutnik, M.V.; Kanevskij, B.L.; Nikozov, A.I.; Sedov, N.D.; Prosin, K.A.; Safonov, L.I.

    1975-01-01

    The finishing of high-strength merchant shapes from alloy steel was tried out under industrial conditions with the equipment of metallurgical plants. After thermomechanical hardening in the production line of the rolling mill, 30KhGSN2A and 40Kh1NVA steel rounds 32 and 31 mm in diameter were straightened on a two-roller straightening machine designed by the All-Union Scientific Research Institute for Metallurgical Machinery (VNII Metmash). This made possible subsequent turning and grinding of the rods. The conditions of straightening, turning and grinding have been worked so as to obtain thermomechanically strengthened and ground rolled products approximating the gauged and ground metal in shape geometry and surface finish. It is shown that the labour-consuming operation of turning can be eliminated by reducing the machining pass of the rolled product, and this lowers the labour required for the finishing operations by 75%. After grinding with 40- and 25-grain abrasive wheels, high strength rolled shapes were obtained with a diameter of 30-0.20 mm and a surface finish of class 6-5 satisfying the technical specifications. (author)

  6. Surface science study of selective ethylene epoxidation catalyzed by the Ag(110) surface: Structural sensitivity

    International Nuclear Information System (INIS)

    Campbell, C.T.

    1984-01-01

    The selective oxidation of ethylene to ethylene epoxide (C 2 H 4 +1/2O 2 →C 2 H 4 O) over Ag is the simplest example of kinetically controlled, selective heterogeneous catalysis. We have studied the steady-state kinetics and selectivity of this reaction for the first time on a clean, well-characterized Ag(110) surface by using a special apparatus which allows rapid (approx.20 s) transfer between a high-pressure catalytic microreactor and an ultrahigh vacuum surface analysis (AES, XPS, LEED, TDS) chamber. The effects of temperature and reactant pressures upon the rate and selectivity are virtually identical on Ag(110) and supported, high surface area Ag catalysts. The absolute specific rate (per Ag surface atom) is, however, some 100-fold higher for Ag(110) than for high surface area catalysts. This is related to the well-known structural sensitivity of this reaction. It is postulated that a small percentage of (110) planes (or [110]-like sites) are responsible for most of the catalytic activity of high surface area catalysts. The high activity of the (110) plane is attributed to its high sticking probability for dissociative oxygen adsorption, since the rate of ethylene epoxidation is shown in a related work [Ref. 1: C. T. Campbell and M. T. Paffett, Surf. Sci. (in press)] to be proportional to the coverage of atomically adsorbed oxygen at constant temperature and ethylene pressure

  7. Composite Fermi surface in the half-filled Landau level with anisotropic electron mass

    Science.gov (United States)

    Ippoliti, Matteo; Geraedts, Scott; Bhatt, Ravindra

    We study the problem of interacting electrons in the lowest Landau level at half filling in the quantum Hall regime, when the electron dispersion is given by an anisotropic mass tensor. Based on experimental observations and theoretical arguments, the ground state of the system is expected to consist of composite Fermions filling an elliptical Fermi sea, with the anisotropy of the ellipse determined by the competing effects of the isotropic Coulomb interaction and anisotropic electron mass tensor. We test this idea quantitatively by using a numerical density matrix renormalization group method for quantum Hall systems on an infinitely long cylinder. Singularities in the structure factor allow us to map the Fermi surface of the composite Fermions. We compute the composite Fermi surface anisotropy for several values of the electron mass anisotropy which allow us to deduce the functional dependence of the former on the latter. This research was supported by Department of Energy Office of Basic Energy Sciences through Grant No. DE-SC0002140.

  8. Uncertainty Quantification for Ice Sheet Science and Sea Level Projections

    Science.gov (United States)

    Boening, C.; Schlegel, N.; Limonadi, D.; Schodlok, M.; Seroussi, H. L.; Larour, E. Y.; Watkins, M. M.

    2017-12-01

    In order to better quantify uncertainties in global mean sea level rise projections and in particular upper bounds, we aim at systematically evaluating the contributions from ice sheets and potential for extreme sea level rise due to sudden ice mass loss. Here, we take advantage of established uncertainty quantification tools embedded within the Ice Sheet System Model (ISSM) as well as sensitivities to ice/ocean interactions using melt rates and melt potential derived from MITgcm/ECCO2. With the use of these tools, we conduct Monte-Carlo style sampling experiments on forward simulations of the Antarctic ice sheet, by varying internal parameters and boundary conditions of the system over both extreme and credible worst-case ranges. Uncertainty bounds for climate forcing are informed by CMIP5 ensemble precipitation and ice melt estimates for year 2100, and uncertainty bounds for ocean melt rates are derived from a suite of regional sensitivity experiments using MITgcm. Resulting statistics allow us to assess how regional uncertainty in various parameters affect model estimates of century-scale sea level rise projections. The results inform efforts to a) isolate the processes and inputs that are most responsible for determining ice sheet contribution to sea level; b) redefine uncertainty brackets for century-scale projections; and c) provide a prioritized list of measurements, along with quantitative information on spatial and temporal resolution, required for reducing uncertainty in future sea level rise projections. Results indicate that ice sheet mass loss is dependent on the spatial resolution of key boundary conditions - such as bedrock topography and melt rates at the ice-ocean interface. This work is performed at and supported by the California Institute of Technology's Jet Propulsion Laboratory. Supercomputing time is also supported through a contract with the National Aeronautics and Space Administration's Cryosphere program.

  9. Laser surface processing with controlled nitrogen-argon concentration levels for regulated surface life time

    Science.gov (United States)

    Obeidi, M. Ahmed; McCarthy, E.; Brabazon, D.

    2018-03-01

    Laser surface modification can be used to enhance the mechanical properties of a material, such as hardness, toughness, fatigue strength, and corrosion resistance. Surface nitriding is a widely used thermochemical method of surface modification, in which nitrogen is introduced into a metal or other material at an elevated temperature within a furnace. It is used on parts where there is a need for increased wear resistance, corrosion resistance, fatigue life, and hardness. Laser nitriding is a novel method of nitriding where the surface is heated locally by a laser, either in an atmosphere of nitrogen or with a jet of nitrogen delivered to the laser heated site. It combines the benefits of laser modification with those of nitriding. Recent work on high toughness tool steel samples has shown promising results due to the increased nitrogen gas impingement onto the laser heated region. Increased surface activity and nitrogen adsorption was achieved which resulted in a deeper and harder surface compared to conventional hardening methods. In this work, the effects of the laser power, pulse repetition frequency, and overlap percentage on laser surface treatment of 316 L SST steel samples with an argon-nitrogen jet will be presented. Resulting microstructure, phase type, microhardness, and wear resistance are presented.

  10. An Examination of High School Social Science Students' Levels Motivation towards Learning Geography

    Science.gov (United States)

    Yildirim, Tahsin

    2017-01-01

    This aim of this research was to examine the levels of motivation among high school social science students towards learning geography. The study group consisted of 397 students from different classes at Aksaray Ahmet Cevdet Pasa High School in the College of Social Science. The research was carried out with a scanning model, with data obtained…

  11. Conceptual Demand of Science Curricula: A Study at the Middle School Level

    Science.gov (United States)

    Calado, Sílvia; Neves, Isabel P.; Morais, Ana M.

    2013-01-01

    This article addresses the issue of the level of conceptual demand of science curricula by analysing the case of the current Portuguese Natural Sciences curriculum for middle school. Conceptual demand is seen in terms of the complexity of cognitive skills, the complexity of scientific knowledge and the intra-disciplinary relations between distinct…

  12. Environmental Studies and Environmental Science at GCE '0' and 'A' Level.

    Science.gov (United States)

    Gayford, Christopher G.

    1983-01-01

    Reports on environmental studies/science at General Certificate of Examination (GCE) ordinary ("0") and advanced ("A") levels. Questionnaires were used to survey teachers (focusing on their professional training and why they teach environmental studies/science courses) and to determine the relationship between environmental…

  13. An investigation of children's levels of inquiry in an informal science setting

    Science.gov (United States)

    Clark-Thomas, Beth Anne

    Elementary school students' understanding of both science content and processes are enhanced by the higher level thinking associated with inquiry-based science investigations. Informal science setting personnel, elementary school teachers, and curriculum specialists charged with designing inquiry-based investigations would be well served by an understanding of the varying influence of certain present factors upon the students' willingness and ability to delve into such higher level inquiries. This study examined young children's use of inquiry-based materials and factors which may influence the level of inquiry they engaged in during informal science activities. An informal science setting was selected as the context for the examination of student inquiry behaviors because of the rich inquiry-based environment present at the site and the benefits previously noted in the research regarding the impact of informal science settings upon the construction of knowledge in science. The study revealed several patterns of behavior among children when they are engaged in inquiry-based activities at informal science exhibits. These repeated behaviors varied in the children's apparent purposeful use of the materials at the exhibits. These levels of inquiry behavior were taxonomically defined as high/medium/low within this study utilizing a researcher-developed tool. Furthermore, in this study adult interventions, questions, or prompting were found to impact the level of inquiry engaged in by the children. This study revealed that higher levels of inquiry were preceded by task directed and physical feature prompts. Moreover, the levels of inquiry behaviors were haltered, even lowered, when preceded by a prompt that focused on a science content or concept question. Results of this study have implications for the enhancement of inquiry-based science activities in elementary schools as well as in informal science settings. These findings have significance for all science educators

  14. Evaluation of the Level of ICT Integration in Sciences Subjects at the ...

    African Journals Online (AJOL)

    Evaluation of the Level of ICT Integration in Sciences Subjects at the Namibian ... The study was informed by Rogers' theory of diffusion and adopted a qualitative ... A semi- structured interview guide and an observation schedule were used to ...

  15. Evaluation of constructivist pedagogy: Influence on critical thinking skills, science fair participation and level of performance

    Science.gov (United States)

    Foxx, Robbie Evelyn

    Science education reform, driven by a rapidly advancing technological society, demands the attention of both elementary and middle school curriculum-developers. Science education training in current standards (National Research Council [NRC] Standards 1996) emphasize inquiry, which is reported to be a basic tenet of the theory known as constructivism (NAASP, 1996; Cohen, 1988; Conley, 1993; Friedman, 1999; Newman, Marks, & Gamoran, 1996; Smerdon & Burkam 1999; Sizer 1992; Talbert & McLaughlin 1993; Tobin & Gallagher, 1987; Yager, 1991, 2000). Pedagogy focusing on the tenets of constructivist theory, at the intermediate level, can address current science standards. Many science educators believe participation in science fairs helps students develop the attitudes, skills, and knowledge that will help them to be comfortable and successful in the scientific and technological society (Czerniak, 1996). Competing in science fairs is one vehicle which allows students to apply science to societal issues, solve problems and model those things scientists do. Moreover, constructing a science fair project is suggested as being an excellent means to foster the development of concepts necessary in promoting scientific literacy (Czerniak, 1996). Research further suggests that through science fairs or other inquiry activities, students construct their knowledge with fewer misconceptions as they explore and discover the nature of science (NRC 1996). Tohn 's study (as cited in Bellipanni, 1994) stated that science fairs are a major campaign to increase student skills and to allow students a chance to have fun with science. The purpose of this research was twofold: (1) to assess science problem solving skills of students instructed using constructivist pedagogy, and (2) to explore the effects of constructivist pedagogy's influence(s) on science fair participation/placement. Students' attitudes resulting from these experiences were examined as well.

  16. New Material Development for Surface Layer and Surface Technology in Tribology Science to Improve Energy Efficiency

    International Nuclear Information System (INIS)

    Ismail, R.; Tauviqirrahman, M.; Jamari; Schipper, D. J.

    2009-01-01

    This paper reviews the development of new material and surface technology in tribology and its contribution to energy efficiency. Two examples of the economic benefits, resulted from the optimum tribology in the transportation sector and the manufacturing industry are discussed. The new materials are proposed to modify the surface property by laminating the bulk material with thin layer/coating. Under a suitable condition, the thin layer on a surface can provide a combination of good wear, a low friction and corrosion resistance for the mechanical components. The innovation in layer technology results molybdenum disulfide (MoS2), diamond like carbon (DLC), cubic boron nitride (CBN) and diamond which perform satisfactory outcome. The application of the metallic coatings to carbon fibre reinforced polymer matrix composites (CFRP) has the capacity to provide considerable weight and power savings for many engineering components. The green material for lubricant and additives such as the use of sunflower oil which possesses good oxidation resistance and the use of mallee leaves as bio‐degradable solvent are used to answer the demand of the environmentally friendly material with good performance. The tribology research implementation for energy efficiency also touches the simple things around us such as: erasing the laser‐print in a paper with different abrasion techniques. For the technology in the engineering surface, the consideration for generating the suitable surface of the components in running‐in period has been discussed in order to prolong the components life and reduce the machine downtime. The conclusion, tribology can result in reducing manufacturing time, reducing the maintenance requirements, prolonging the service interval, improving durability, reliability and mechanical components life, and reducing harmful exhaust emission and waste. All of these advantages will increase the energy efficiency and the economic benefits.

  17. New Material Development for Surface Layer and Surface Technology in Tribology Science to Improve Energy Efficiency

    Science.gov (United States)

    Ismail, R.; Tauviqirrahman, M.; Jamari, Jamari; Schipper, D. J.

    2009-09-01

    This paper reviews the development of new material and surface technology in tribology and its contribution to energy efficiency. Two examples of the economic benefits, resulted from the optimum tribology in the transportation sector and the manufacturing industry are discussed. The new materials are proposed to modify the surface property by laminating the bulk material with thin layer/coating. Under a suitable condition, the thin layer on a surface can provide a combination of good wear, a low friction and corrosion resistance for the mechanical components. The innovation in layer technology results molybdenum disulfide (MoS2), diamond like carbon (DLC), cubic boron nitride (CBN) and diamond which perform satisfactory outcome. The application of the metallic coatings to carbon fibre reinforced polymer matrix composites (CFRP) has the capacity to provide considerable weight and power savings for many engineering components. The green material for lubricant and additives such as the use of sunflower oil which possesses good oxidation resistance and the use of mallee leaves as bio-degradable solvent are used to answer the demand of the environmentally friendly material with good performance. The tribology research implementation for energy efficiency also touches the simple things around us such as: erasing the laser-print in a paper with different abrasion techniques. For the technology in the engineering surface, the consideration for generating the suitable surface of the components in running-in period has been discussed in order to prolong the components life and reduce the machine downtime. The conclusion, tribology can result in reducing manufacturing time, reducing the maintenance requirements, prolonging the service interval, improving durability, reliability and mechanical components life, and reducing harmful exhaust emission and waste. All of these advantages will increase the energy efficiency and the economic benefits.

  18. Mars' surface radiation environment measured with the Mars science laboratory's curiosity rover

    NARCIS (Netherlands)

    Hassler, D.M.; Zeitlin, C.; Wimmer-Schweingruber, R.F.; Ehresmann, B.; Rafkin, S.; Eigenbrode, J.L.; Brinza, D.E.; Weigle, G.; Böttcher, S.; Böhm, E.; Burmeister, S.; Guo, J.; Köhler, J.; Martin, C.; Reitz, G.; Cucinotta, F.A.; Kim, M.-H.; Grinspoon, D.; Bullock, M.A.; Posner, A.; Gómez-Elvira, J.; Vasavada, A.; Grotzinger, J.P.; MSL Science Team, the|info:eu-repo/dai/nl/292012217

    2014-01-01

    The Radiation Assessment Detector (RAD) on the Mars Science Laboratory’s Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose

  19. Chemical bonding of water to metal surfaces studied with core-level spectroscopies

    DEFF Research Database (Denmark)

    Schiros, T.; Andersson, Klas Jerker; Pettersson, L.G.M.

    2010-01-01

    The nature of the contact layer of water on surfaces is of relevance for many practical fields, including corrosion, electrochemistry, environmental science and heterogeneous catalysis. Here we focus on the geometric and electronic structure of the water contact layer on transition metal surfaces......-specific information on the partial local density of states, local atomic structure, geometrical parameters and molecular orientation, allowing general principles for water-metal interaction to be derived....

  20. Nutrition sciences as part of school education on secondary level

    Directory of Open Access Journals (Sweden)

    Christiane Hillger

    2008-03-01

    Full Text Available

    Background: The following article focuses on nutrition related topics that had been implemented in the curricula of secondary level schools in Saxony, Germany, during their reorganisation. The overall aim was to make children and adolescents more sensitive to nutrition related topics in their daily lives. Thus, the lesson plans that have been created for the teachers will be introduced and a preview of further steps will be given.

    Methods: For the subject economics-technology-household exemplary lesson plans within the framework of the Saxon curricula were created for secondary level schools from grades eight to ten. Furthermore, conceptions for project days and different kinds of courses were prepared for nutrition related topics. After the lesson plans were tested and three teachers were consulted, feedback from all of the subject teachers was obtained via interview for qualitative analysis. Fifty-two pupils were asked to answer a questionnaire. The responses according to the lessons were taken partially standardised and were evaluated.

    Results: Teachers as well as pupils appreciated the complex lesson plans and materials on scientific basis.The consulted subject teachers emphasised that the lesson plans can be regarded as a fundamental preparation for their further work. If necessary they need to be adapted to the teacher’s ideas and special circumstances in school.

    Conclusions: With the preparation of the lesson plans important steps were realised within the restructuring process of Saxon curricula. Thus, the implementation of nutrition related topics in school curricula could be achieved.

  1. Mineral Surface-Templated Self-Assembling Systems: Case Studies from Nanoscience and Surface Science towards Origins of Life Research

    Directory of Open Access Journals (Sweden)

    Richard J. Gillams

    2018-05-01

    Full Text Available An increasing body of evidence relates the wide range of benefits mineral surfaces offer for the development of early living systems, including adsorption of small molecules from the aqueous phase, formation of monomeric subunits and their subsequent polymerization, and supramolecular assembly of biopolymers and other biomolecules. Each of these processes was likely a necessary stage in the emergence of life on Earth. Here, we compile evidence that templating and enhancement of prebiotically-relevant self-assembling systems by mineral surfaces offers a route to increased structural, functional, and/or chemical complexity. This increase in complexity could have been achieved by early living systems before the advent of evolvable systems and would not have required the generally energetically unfavorable formation of covalent bonds such as phosphodiester or peptide bonds. In this review we will focus on various case studies of prebiotically-relevant mineral-templated self-assembling systems, including supramolecular assemblies of peptides and nucleic acids, from nanoscience and surface science. These fields contain valuable information that is not yet fully being utilized by the origins of life and astrobiology research communities. Some of the self-assemblies that we present can promote the formation of new mineral surfaces, similar to biomineralization, which can then catalyze more essential prebiotic reactions; this could have resulted in a symbiotic feedback loop by which geology and primitive pre-living systems were closely linked to one another even before life’s origin. We hope that the ideas presented herein will seed some interesting discussions and new collaborations between nanoscience/surface science researchers and origins of life/astrobiology researchers.

  2. Mineral Surface-Templated Self-Assembling Systems: Case Studies from Nanoscience and Surface Science towards Origins of Life Research.

    Science.gov (United States)

    Gillams, Richard J; Jia, Tony Z

    2018-05-08

    An increasing body of evidence relates the wide range of benefits mineral surfaces offer for the development of early living systems, including adsorption of small molecules from the aqueous phase, formation of monomeric subunits and their subsequent polymerization, and supramolecular assembly of biopolymers and other biomolecules. Each of these processes was likely a necessary stage in the emergence of life on Earth. Here, we compile evidence that templating and enhancement of prebiotically-relevant self-assembling systems by mineral surfaces offers a route to increased structural, functional, and/or chemical complexity. This increase in complexity could have been achieved by early living systems before the advent of evolvable systems and would not have required the generally energetically unfavorable formation of covalent bonds such as phosphodiester or peptide bonds. In this review we will focus on various case studies of prebiotically-relevant mineral-templated self-assembling systems, including supramolecular assemblies of peptides and nucleic acids, from nanoscience and surface science. These fields contain valuable information that is not yet fully being utilized by the origins of life and astrobiology research communities. Some of the self-assemblies that we present can promote the formation of new mineral surfaces, similar to biomineralization, which can then catalyze more essential prebiotic reactions; this could have resulted in a symbiotic feedback loop by which geology and primitive pre-living systems were closely linked to one another even before life’s origin. We hope that the ideas presented herein will seed some interesting discussions and new collaborations between nanoscience/surface science researchers and origins of life/astrobiology researchers.

  3. Earth System Science at NASA: Teleconnections Between Sea Surface Temperature and Epidemics in Africa

    Science.gov (United States)

    Meeson, Blanche W.

    2000-01-01

    The research carried out in the Earth Sciences in NASA and at NASA's Goddard Space Flight Center will be the focus of the presentations. In addition, one research project that links sea surface temperature to epidemics in Africa will be highlighted. At GSFC research interests span the full breath of disciplines in Earth Science. Branches and research groups focus on areas as diverse as planetary geomagnetics and atmospheric chemistry. These organizations focus on atmospheric sciences (atmospheric chemistry, climate and radiation, regional processes, atmospheric modeling), hydrological sciences (snow, ice, oceans, and seasonal-to-interannual prediction), terrestrial physics (geology, terrestrial biology, land-atmosphere interactions, geophysics), climate modeling (global warming, greenhouse gases, climate change), on sensor development especially using lidar and microwave technologies, and on information technologies, that enable support of scientific and technical research.

  4. Acidic deposition: State of science and technology. Report 15. Liming acidic surface waters. Final report

    International Nuclear Information System (INIS)

    Olem, H.; Thornelof, E.; Sandoy, S.; Schreiber, R.K.

    1990-09-01

    The document describes the science and technology of aquatic liming--a method for improving the water quality of acidic surface waters to restore or enhance fisheries. The report is a comprehensive compilation of years of research in North America and Europe by dozens of scientists. Several mitigation technologies--including those that have only been proposed--are critically evaluated along with the effects of liming on water chemistry and aquatic biota. Through these evaluations, the state of the science and technology of aquatic liming is identified for the reader. Whole-lake liming is now recognized as a valuable management tool for acidic surface waters and their fisheries. However, some liming technologies are considered experimental and will need further evaluation. Distinctions between technologies are included--as is the distinction between liming acidic surface waters and reducing acidifying emissions

  5. Document Type Profiles in Nature, Science, and PNAS: Journal and Country Level

    Directory of Open Access Journals (Sweden)

    Jielan Ding

    2016-09-01

    Full Text Available Purpose: In this contribution, we want to detect the document type profiles of the three prestigious journals Nature, Science, and Proceedings of the National Academy of Sciences of the United States (PNAS with regard to two levels: journal and country. Design/methodology/approach: Using relative values based on fractional counting, we investigate the distribution of publications across document types at both the journal and country level, and we use (cosine document type profile similarity values to compare pairs of publication years within countries. Findings: Nature and Science mainly publish Editorial Material, Article, News Item and Letter, whereas the publications of PNAS are heavily concentrated on Article. The shares of Article for Nature and Science are decreasing slightly from 1999 to 2014, while the corresponding shares of Editorial Material are increasing. Most studied countries focus on Article and Letter in Nature, but on Letter in Science and PNAS. The document type profiles of some of the studied countries change to a relatively large extent over publication years. Research limitations: The main limitation of this research concerns the Web of Science classification of publications into document types. Since the analysis of the paper is based on document types of Web of Science, the classification in question is not free from errors, and the accuracy of the analysis might be affected. Practical implications: Results show that Nature and Science are quite diversified with regard to document types. In bibliometric assessments, where publications in Nature and Science play a role, other document types than Article and Review might therefore be taken into account. Originality/value: Results highlight the importance of other document types than Article and Review in Nature and Science. Large differences are also found when comparing the country document type profiles of the three journals with the corresponding profiles in all Web of

  6. Predictors of cultural capital on science academic achievement at the 8th grade level

    Science.gov (United States)

    Misner, Johnathan Scott

    The purpose of the study was to determine if students' cultural capital is a significant predictor of 8th grade science achievement test scores in urban locales. Cultural capital refers to the knowledge used and gained by the dominant class, which allows social and economic mobility. Cultural capital variables include magazines at home and parental education level. Other variables analyzed include socioeconomic status (SES), gender, and English language learners (ELL). This non-experimental study analyzed the results of the 2011 Eighth Grade Science National Assessment of Educational Progress (NAEP). The researcher analyzed the data using a multivariate stepwise regression analysis. The researcher concluded that the addition of cultural capital factors significantly increased the predictive power of the model where magazines in home, gender, student classified as ELL, parental education level, and SES were the independent variables and science achievement was the dependent variable. For alpha=0.05, the overall test for the model produced a R2 value of 0.232; therefore the model predicted 23.2% of variance in science achievement results. Other major findings include: higher measures of home resources predicted higher 2011 NAEP eighth grade science achievement; males were predicted to have higher 2011 NAEP 8 th grade science achievement; classified ELL students were predicted to score lower on the NAEP eight grade science achievement; higher parent education predicted higher NAEP eighth grade science achievement; lower measures of SES predicted lower 2011 NAEP eighth grade science achievement. This study contributed to the research in this field by identifying cultural capital factors that have been found to have statistical significance on predicting eighth grade science achievement results, which can lead to strategies to help improve science academic achievement among underserved populations.

  7. From inside the black box: Teacher perceptions of science instruction at the elementary level

    Science.gov (United States)

    Ferrini, Cynthia D.

    Science education reform projects aimed at elementary school children arose in the 1960's. The most prevalent of these reforms utilized the inquiry, or hands-on, science method. Billions of dollars have been invested in these reforms. Yet, reports indicate that science is not being taught at the level one might expect in elementary schools. This research was an analysis of the problems and concerns teachers at one school district faced as they tried to implement and sustain elementary inquiry science instruction. The district chosen was a large suburban district in the Western United States. The population was ninety percent Caucasian with a slightly more ethnically diverse school population. This district was chosen because it had an elementary science program for over twenty years and had received national acclaim for that program. The district had a stable and homogeneous staff there was a low administrator and teacher turnover rate and the elementary teaching population was ninety percent Caucasian and ninety percent female. Interviews with administrators and teachers were conducted. Data were collected from focus groups of teachers and science partners. Observations of elementary science classroom instruction and professional development sessions were made. Results of this research indicated that one important key to elementary science reform rests in the hands of teachers. Once the door to the classroom is closed, the teacher can decide to teach or not to teach science. The findings of this research illustrate that teachers hold ideas about science and science instruction that are antithetical to some tenets of inquiry science. Until these ideas are addressed it will be difficult, if not impossible, to implement a systemic elementary inquiry science program. This study demonstrates that professional development for elementary teachers in science needs to change from a focus on the mechanical usage of individual units to a focus on teacher expectations for

  8. Effects of Brain-Based Learning Approach on Students' Motivation and Attitudes Levels in Science Class

    Science.gov (United States)

    Akyurek, Erkan; Afacan, Ozlem

    2013-01-01

    The purpose of the study was to examine the effect of brain-based learning approach on attitudes and motivation levels in 8th grade students' science classes. The main reason for examining attitudes and motivation levels, the effect of the short-term motivation, attitude shows the long-term effect. The pre/post-test control group research model…

  9. TPACK Levels of Physics and Science Teacher Candidates: Problems and Possible Solutions

    Science.gov (United States)

    Bozkurt, Ersin

    2014-01-01

    This research examined whether the technological pedagogical content knowledge (TPACK) of physics and science teachers is at a sufficient level and whether the TPACK level affected the academic achievements of the students. In the research, a mixed method was used quantitatively and qualitatively. In the quantitative part of the research, Provus'…

  10. Sea level and turbidity controls on mangrove soil surface elevation change

    Science.gov (United States)

    Lovelock, Catherine E.; Fernanda Adame, Maria; Bennion, Vicki; Hayes, Matthew; Reef, Ruth; Santini, Nadia; Cahoon, Donald R.

    2015-01-01

    Increases in sea level are a threat to seaward fringing mangrove forests if levels of inundation exceed the physiological tolerance of the trees; however, tidal wetlands can keep pace with sea level rise if soil surface elevations can increase at the same pace as sea level rise. Sediment accretion on the soil surface and belowground production of roots are proposed to increase with increasing sea level, enabling intertidal habitats to maintain their position relative to mean sea level, but there are few tests of these predictions in mangrove forests. Here we used variation in sea level and the availability of sediments caused by seasonal and inter-annual variation in the intensity of La Nina-El Nino to assess the effects of increasing sea level on surface elevation gains and contributing processes (accretion on the surface, subsidence and root growth) in mangrove forests. We found that soil surface elevation increased with mean sea level (which varied over 250 mm during the study) and with turbidity at sites where fine sediment in the water column is abundant. In contrast, where sediments were sandy, rates of surface elevation gain were high, but not significantly related to variation in turbidity, and were likely to be influenced by other factors that deliver sand to the mangrove forest. Root growth was not linked to soil surface elevation gains, although it was associated with reduced shallow subsidence, and therefore may contribute to the capacity of mangroves to keep pace with sea level rise. Our results indicate both surface (sedimentation) and subsurface (root growth) processes can influence mangrove capacity to keep pace with sea level rise within the same geographic location, and that current models of tidal marsh responses to sea level rise capture the major feature of the response of mangroves where fine, but not coarse, sediments are abundant.

  11. Assessment of surface contamination level in an operating uranium ore processing facility of Jaduguda, India

    International Nuclear Information System (INIS)

    Meena, J.S.; Patnaik, R.L.; Jha, V.N.; Sahoo, S.K.; Ravi, P.M.; Tripathi, R.M.

    2014-01-01

    Radiological concern of the occupational workers and the area is given priority over other safety issue in confirmation with the stipulated guideline of national regulatory agency (AERB/FEFCF/SG-2, 2007). The key concern from the radiological hazard evaluation point of view is air activity, external gamma level and surface contamination. Present investigations was carried out to ascertain the surface contamination level of uranium ore processing facility at Jaduguda, Jharkhand. For a low grade uranium ore processing industry surface contamination is a major concern in product precipitation and recovery section. In view of this, the ore processing plant can broadly be classified into three areas i.e. ion exchange area, precipitation and product recovery section and other areas. The monitoring results incorporate the level of surface contamination of the plant during the last five years. The geometric mean activity of surface contamination level was 31.1, 34.5 and 9.8 Bq dm -2 in ion exchange, product precipitation and recovery and other areas with GSD of 2, 2.5 and 1.9. In most of the cases the surface contamination level was well within the recommended limit of 100 Bq dm -2 for M class uranium compound. Occasional cases of surface contamination levels exceeding the recommended limit were addressed and areas were decontaminated. Based on the study, modification in the design feature of the surface of the finished product section was also suggested so that the decontamination procedure can be more effectively implemented

  12. An Investigation of Intrinsic Job Satisfaction Levels of Science and Technology Teachers Regarding Some Variables

    Directory of Open Access Journals (Sweden)

    Zafer ADIGÜZEL

    2013-10-01

    Full Text Available In this study, it is aimed to identify intrinsic job satisfaction levels of science and technology teachers. This study had a correlational and comparative survey design and random sampling was employed in this study. The sample consisted of 204 science and technology teachers teaching in Istanbul. The Personal Information Form and the Minnesota Job Satisfaction Questionnaire were used to collect the data. Significant differences were found for the school type, belongings (car, house, presence of another teacher in the family, graduate education, and advice for becoming a science teacher. On the contrary, nonsignificant differences were found for gender, age, marital status, presence of children, the number of children, teaching except science, teaching experience, in-service training, the number of schools served for, administrative duty, extra job, the type of extra job, level of extra income.

  13. Grade Level Differences in High School Students' Conceptions of and Motives for Learning Science

    Science.gov (United States)

    Wang, Ya-Ling; Tsai, Chin-Chung

    2017-08-01

    Students' conceptions of learning science and their relations with motive for learning may vary as the education level increases. This study aimed to compare the quantitative patterns in students' conceptions of learning science (COLS) and motives for learning science (MLS) across grade levels by adopting two survey instruments. A total of 768 high school students were surveyed in Taiwan, including 204 eighth graders, 262 tenth graders, and 302 12th graders. In the current research, memorizing, testing, and calculating and practicing were categorized as reproductive conceptions of learning science, while increase of knowledge, applying, understanding and seeing-in-a-new-way were regarded as constructivist conceptions. The results of multivariate analyses of variance (MANOVA) revealed that conceptions of learning science are more constructivist as education level increases. Both tenth graders and 12th graders endorsed understanding, seeing-in-a-new-way, and the constructivist COLS composite more strongly than the eighth graders did. In addition, the results of multigroup structural equation modeling (SEM) analysis indicated that the positive relations between testing and reproductive COLS were stronger as the grade level increased, while the negative relations between reproductive COLS and deep motive were tighter with the increase in grade level.

  14. Strategies to Support PGCE Mathematics and Science Students Preparing for Assignments at Masters Level

    OpenAIRE

    Tas, Maarten; Forsythe, Sue

    2010-01-01

    The main aim of this study was to analyse and evaluate the effectiveness of support strategies being put into place for students who need to write assignments at Masters Level. In preparation for writing a 5000 word assignment on an aspect of teaching Mathematics or Science, 57 Science and Mathematics PGCE students were asked to write a 500 word synopsis which included an introduction, description of the main focus, questions that the assignment would address and possible strategies for teach...

  15. Beam line 4: A dedicated surface science facility at Daresbury Laboratory

    International Nuclear Information System (INIS)

    Dhanak, V.R.; Robinson, A.W.; van der Laan, G.; Thornton, G.

    1992-01-01

    We describe a beam line currently under construction at the Daresbury Laboratory which forms part of a surface science research facility for the Interdisciplinary Research Centre in Surface Science. The beam line has three branches, two of which are described here. The first branch covers the high-energy range 640 eV≤hν≤10 keV, being equipped with a double-crystal monochromator and a novel multicoated premirror system. The second branch line is optimized for the energy range 15≤hν≤250 eV, using cylindrical focusing mirrors, a spherical diffraction grating and an ellipsoidal refocusing mirror to achieve high resolution with a small spot size

  16. On the implications of the Surface Water and Ocean Topography (SWOT) mission for hydrologic science and applications (Invited)

    Science.gov (United States)

    Lettenmaier, D. P.

    2010-12-01

    The SWOT mission will provide surface water elevation and extent information with unprecedented accuracy and spatial resolution globally. All of the implications of thedata that SWOT will produce for the hydrologic science and applications communities are not yet apparent. The SWOT data will, however, certainly offer groundbreaking opportunities for estimation of two key terms in the land surface water budget: surface water storage (in almost all water bodies with surface area exceeding about 1 km2) and derived discharge for many of the world’s large rivers (widths greater than roughly 100-250 m). Among just a few of the science questions that the observations should allow us to address are a) what are the dynamics of floods and overbank flows in large rivers? b) what is the contribution of long-term, seasonal, and interannual storage in reservoirs, lakes, and wetlands to sea level? c) what is the magnitude of surface water storage changes at seasonal to decadal time scales and continental spatial scales relative to soil moisture and groundwater? d) what will be the implications of SWOT-based estimates of reservoir storage and storage change to the management of transboundary rivers? These quite likely are among just a few of the questions that SWOT will help elucidate. Others no doubt will arise from creative analyses of SWOT data in combination with data from other missions I conclude with a discussion of mechanisms that will help foster a community to investigate these and other questions, and the implications of a SWOT data policy.

  17. Electron mobility on the surface of liquid Helium: influence of surface level atoms and depopulation of lowest subbands

    International Nuclear Information System (INIS)

    Grigoriev, P. D.; Dyugaev, A. M.; Lebedeva, E. V.

    2008-01-01

    The temperature dependence of electron mobility is examined. We calculate the contribution to the electron scattering rate from the surface level atoms (SLAs), proposed in [10]. This contribution is substantial at low temperatures T < 0.5, when the He vapor concentration is exponentially small. We also study the effect of depopulation of the lowest energy subband, which leads to an increase in the electron mobility at high temperature. The results explain certain long-standing discrepancies between the existing theory and experiment on electron mobility on the surface of liquid helium

  18. Levels of prospective science teachers’ ability to structure 5E model

    Directory of Open Access Journals (Sweden)

    Kaçan Sibel Demir

    2017-01-01

    Full Text Available The research was conducted with 3rd year prospective science students, who study at the science teaching department of a university in Istanbul province. For that purpose, 34 prospective science teachers cooperated and participated in the study. In the study, the prospective teachers were asked to select a certain subject and plan that subject in accordance with the 5E model. Therefore, the objective of the study is to determine the levels of prospective science teachers’ ability to structure the 5E model. The data retrieved from the study were analyzed ad compared through content analysis and percentages. The results of the study suggest that some prospective teachers are not sufficient at each phase of the 5E model, thereby the researchers made suggestions for that situation.

  19. The New Horizons Radio Science Experiment: Expected Performance in Measurements of Pluto's Atmospheric Structure, Surface Pressure, and Surface Temperature

    Science.gov (United States)

    Hinson, D. P.; Linscott, I.; Woods, W. W.; Tyler, G. L.; Bird, M. K.; Paetzold, M.; Strobel, D. F.

    2014-12-01

    The New Horizons (NH) payload includes a Radio Science Experiment (REX) for investigating key characteristics of Pluto and Charon during the upcoming flyby in July 2015. REX flight equipment augments the NH radio transceiver used for spacecraft communications and tracking. The REX hardware implementation requires 1.6 W and 160 g. This presentation will focus on the final design and the predicted performance of two high-priority observations. First, REX will receive signals from a pair of 70-m antennas on Earth - each transmitting 20 kW at 4.2-cm wavelength - during a diametric radio occultation by Pluto. The data recorded by REX will reveal the surface pressure, the temperature structure of the lower atmosphere, and the surface radius. Second, REX will measure the thermal emission from Pluto at 4.2-cm wavelength during two linear scans across the disk at close range when both the dayside and the nightside are visible, allowing the surface temperature and its spatial variations to be determined. Both scans extend from limb to limb with a resolution of about 10 pixels; one bisects Pluto whereas the second crosses the winter pole. We will illustrate the capabilities of REX by reviewing the method of analysis and the precision achieved in a lunar occultation observed by New Horizons in May 2011. Re-analysis of radio occultation measurements by Voyager 2 at Triton is also under way. More generally, REX objectives include a radio occultation search for Pluto's ionosphere; examination of Charon through both radio occultation and radiometry; a search for a radar echo from Pluto's surface; and improved knowledge of the Pluto system mass and the Pluto-Charon mass ratio from a combination of two-way and one-way Doppler frequency measurements.

  20. Assessment of environments for Mars Science Laboratory entry, descent, and surface operations

    Science.gov (United States)

    Vasavada, Ashwin R.; Chen, Allen; Barnes, Jeffrey R.; Burkhart, P. Daniel; Cantor, Bruce A.; Dwyer-Cianciolo, Alicia M.; Fergason, Robini L.; Hinson, David P.; Justh, Hilary L.; Kass, David M.; Lewis, Stephen R.; Mischna, Michael A.; Murphy, James R.; Rafkin, Scot C.R.; Tyler, Daniel; Withers, Paul G.

    2012-01-01

    The Mars Science Laboratory mission aims to land a car-sized rover on Mars' surface and operate it for at least one Mars year in order to assess whether its field area was ever capable of supporting microbial life. Here we describe the approach used to identify, characterize, and assess environmental risks to the landing and rover surface operations. Novel entry, descent, and landing approaches will be used to accurately deliver the 900-kg rover, including the ability to sense and "fly out" deviations from a best-estimate atmospheric state. A joint engineering and science team developed methods to estimate the range of potential atmospheric states at the time of arrival and to quantitatively assess the spacecraft's performance and risk given its particular sensitivities to atmospheric conditions. Numerical models are used to calculate the atmospheric parameters, with observations used to define model cases, tune model parameters, and validate results. This joint program has resulted in a spacecraft capable of accessing, with minimal risk, the four finalist sites chosen for their scientific merit. The capability to operate the landed rover over the latitude range of candidate landing sites, and for all seasons, was verified against an analysis of surface environmental conditions described here. These results, from orbital and model data sets, also drive engineering simulations of the rover's thermal state that are used to plan surface operations.

  1. Mars' Surface Radiation Environment Measured with the Mars Science Laboratory's Curiosity Rover

    Science.gov (United States)

    Hassler, Donald M.; Zeitlin, Cary; Wimmer-Schweingruber, Robert F.; Ehresmann, Bent; Rafkin, Scot; Eigenbrode, Jennifer L.; Brinza, David E.; Weigle, Gerald; Böttcher, Stephan; Böhm, Eckart; Burmeister, Soenke; Guo, Jingnan; Köhler, Jan; Martin, Cesar; Reitz, Guenther; Cucinotta, Francis A.; Kim, Myung-Hee; Grinspoon, David; Bullock, Mark A.; Posner, Arik; Gómez-Elvira, Javier; Vasavada, Ashwin; Grotzinger, John P.; MSL Science Team; Kemppinen, Osku; Cremers, David; Bell, James F.; Edgar, Lauren; Farmer, Jack; Godber, Austin; Wadhwa, Meenakshi; Wellington, Danika; McEwan, Ian; Newman, Claire; Richardson, Mark; Charpentier, Antoine; Peret, Laurent; King, Penelope; Blank, Jennifer; Schmidt, Mariek; Li, Shuai; Milliken, Ralph; Robertson, Kevin; Sun, Vivian; Baker, Michael; Edwards, Christopher; Ehlmann, Bethany; Farley, Kenneth; Griffes, Jennifer; Miller, Hayden; Newcombe, Megan; Pilorget, Cedric; Rice, Melissa; Siebach, Kirsten; Stack, Katie; Stolper, Edward; Brunet, Claude; Hipkin, Victoria; Léveillé, Richard; Marchand, Geneviève; Sánchez, Pablo Sobrón; Favot, Laurent; Cody, George; Steele, Andrew; Flückiger, Lorenzo; Lees, David; Nefian, Ara; Martin, Mildred; Gailhanou, Marc; Westall, Frances; Israël, Guy; Agard, Christophe; Baroukh, Julien; Donny, Christophe; Gaboriaud, Alain; Guillemot, Philippe; Lafaille, Vivian; Lorigny, Eric; Paillet, Alexis; Pérez, René; Saccoccio, Muriel; Yana, Charles; Armiens-Aparicio, Carlos; Rodríguez, Javier Caride; Blázquez, Isaías Carrasco; Gómez, Felipe Gómez; Hettrich, Sebastian; Malvitte, Alain Lepinette; Jiménez, Mercedes Marín; Martínez-Frías, Jesús; Martín-Soler, Javier; Martín-Torres, F. Javier; Jurado, Antonio Molina; Mora-Sotomayor, Luis; Caro, Guillermo Muñoz; López, Sara Navarro; Peinado-González, Verónica; Pla-García, Jorge; Manfredi, José Antonio Rodriguez; Romeral-Planelló, Julio José; Fuentes, Sara Alejandra Sans; Martinez, Eduardo Sebastian; Redondo, Josefina Torres; Urqui-O'Callaghan, Roser; Mier, María-Paz Zorzano; Chipera, Steve; Lacour, Jean-Luc; Mauchien, Patrick; Sirven, Jean-Baptiste; Manning, Heidi; Fairén, Alberto; Hayes, Alexander; Joseph, Jonathan; Squyres, Steven; Sullivan, Robert; Thomas, Peter; Dupont, Audrey; Lundberg, Angela; Melikechi, Noureddine; Mezzacappa, Alissa; Berger, Thomas; Matthia, Daniel; Prats, Benito; Atlaskin, Evgeny; Genzer, Maria; Harri, Ari-Matti; Haukka, Harri; Kahanpää, Henrik; Kauhanen, Janne; Kemppinen, Osku; Paton, Mark; Polkko, Jouni; Schmidt, Walter; Siili, Tero; Fabre, Cécile; Wray, James; Wilhelm, Mary Beth; Poitrasson, Franck; Patel, Kiran; Gorevan, Stephen; Indyk, Stephen; Paulsen, Gale; Gupta, Sanjeev; Bish, David; Schieber, Juergen; Gondet, Brigitte; Langevin, Yves; Geffroy, Claude; Baratoux, David; Berger, Gilles; Cros, Alain; d'Uston, Claude; Forni, Olivier; Gasnault, Olivier; Lasue, Jérémie; Lee, Qiu-Mei; Maurice, Sylvestre; Meslin, Pierre-Yves; Pallier, Etienne; Parot, Yann; Pinet, Patrick; Schröder, Susanne; Toplis, Mike; Lewin, Éric; Brunner, Will; Heydari, Ezat; Achilles, Cherie; Oehler, Dorothy; Sutter, Brad; Cabane, Michel; Coscia, David; Israël, Guy; Szopa, Cyril; Dromart, Gilles; Robert, François; Sautter, Violaine; Le Mouélic, Stéphane; Mangold, Nicolas; Nachon, Marion; Buch, Arnaud; Stalport, Fabien; Coll, Patrice; François, Pascaline; Raulin, François; Teinturier, Samuel; Cameron, James; Clegg, Sam; Cousin, Agnès; DeLapp, Dorothea; Dingler, Robert; Jackson, Ryan Steele; Johnstone, Stephen; Lanza, Nina; Little, Cynthia; Nelson, Tony; Wiens, Roger C.; Williams, Richard B.; Jones, Andrea; Kirkland, Laurel; Treiman, Allan; Baker, Burt; Cantor, Bruce; Caplinger, Michael; Davis, Scott; Duston, Brian; Edgett, Kenneth; Fay, Donald; Hardgrove, Craig; Harker, David; Herrera, Paul; Jensen, Elsa; Kennedy, Megan R.; Krezoski, Gillian; Krysak, Daniel; Lipkaman, Leslie; Malin, Michael; McCartney, Elaina; McNair, Sean; Nixon, Brian; Posiolova, Liliya; Ravine, Michael; Salamon, Andrew; Saper, Lee; Stoiber, Kevin; Supulver, Kimberley; Van Beek, Jason; Van Beek, Tessa; Zimdar, Robert; French, Katherine Louise; Iagnemma, Karl; Miller, Kristen; Summons, Roger; Goesmann, Fred; Goetz, Walter; Hviid, Stubbe; Johnson, Micah; Lefavor, Matthew; Lyness, Eric; Breves, Elly; Dyar, M. Darby; Fassett, Caleb; Blake, David F.; Bristow, Thomas; DesMarais, David; Edwards, Laurence; Haberle, Robert; Hoehler, Tori; Hollingsworth, Jeff; Kahre, Melinda; Keely, Leslie; McKay, Christopher; Wilhelm, Mary Beth; Bleacher, Lora; Brinckerhoff, William; Choi, David; Conrad, Pamela; Dworkin, Jason P.; Floyd, Melissa; Freissinet, Caroline; Garvin, James; Glavin, Daniel; Harpold, Daniel; Jones, Andrea; Mahaffy, Paul; Martin, David K.; McAdam, Amy; Pavlov, Alexander; Raaen, Eric; Smith, Michael D.; Stern, Jennifer; Tan, Florence; Trainer, Melissa; Meyer, Michael; Voytek, Mary; Anderson, Robert C.; Aubrey, Andrew; Beegle, Luther W.; Behar, Alberto; Blaney, Diana; Calef, Fred; Christensen, Lance; Crisp, Joy A.; DeFlores, Lauren; Ehlmann, Bethany; Feldman, Jason; Feldman, Sabrina; Flesch, Gregory; Hurowitz, Joel; Jun, Insoo; Keymeulen, Didier; Maki, Justin; Mischna, Michael; Morookian, John Michael; Parker, Timothy; Pavri, Betina; Schoppers, Marcel; Sengstacken, Aaron; Simmonds, John J.; Spanovich, Nicole; Juarez, Manuel de la Torre; Webster, Christopher R.; Yen, Albert; Archer, Paul Douglas; Jones, John H.; Ming, Douglas; Morris, Richard V.; Niles, Paul; Rampe, Elizabeth; Nolan, Thomas; Fisk, Martin; Radziemski, Leon; Barraclough, Bruce; Bender, Steve; Berman, Daniel; Dobrea, Eldar Noe; Tokar, Robert; Vaniman, David; Williams, Rebecca M. E.; Yingst, Aileen; Lewis, Kevin; Leshin, Laurie; Cleghorn, Timothy; Huntress, Wesley; Manhès, Gérard; Hudgins, Judy; Olson, Timothy; Stewart, Noel; Sarrazin, Philippe; Grant, John; Vicenzi, Edward; Wilson, Sharon A.; Hamilton, Victoria; Peterson, Joseph; Fedosov, Fedor; Golovin, Dmitry; Karpushkina, Natalya; Kozyrev, Alexander; Litvak, Maxim; Malakhov, Alexey; Mitrofanov, Igor; Mokrousov, Maxim; Nikiforov, Sergey; Prokhorov, Vasily; Sanin, Anton; Tretyakov, Vladislav; Varenikov, Alexey; Vostrukhin, Andrey; Kuzmin, Ruslan; Clark, Benton; Wolff, Michael; McLennan, Scott; Botta, Oliver; Drake, Darrell; Bean, Keri; Lemmon, Mark; Schwenzer, Susanne P.; Anderson, Ryan B.; Herkenhoff, Kenneth; Lee, Ella Mae; Sucharski, Robert; Hernández, Miguel Ángel de Pablo; Ávalos, Juan José Blanco; Ramos, Miguel; Malespin, Charles; Plante, Ianik; Muller, Jan-Peter; Navarro-González, Rafael; Ewing, Ryan; Boynton, William; Downs, Robert; Fitzgibbon, Mike; Harshman, Karl; Morrison, Shaunna; Dietrich, William; Kortmann, Onno; Palucis, Marisa; Sumner, Dawn Y.; Williams, Amy; Lugmair, Günter; Wilson, Michael A.; Rubin, David; Jakosky, Bruce; Balic-Zunic, Tonci; Frydenvang, Jens; Jensen, Jaqueline Kløvgaard; Kinch, Kjartan; Koefoed, Asmus; Madsen, Morten Bo; Stipp, Susan Louise Svane; Boyd, Nick; Campbell, John L.; Gellert, Ralf; Perrett, Glynis; Pradler, Irina; VanBommel, Scott; Jacob, Samantha; Owen, Tobias; Rowland, Scott; Atlaskin, Evgeny; Savijärvi, Hannu; García, César Martín; Mueller-Mellin, Reinhold; Bridges, John C.; McConnochie, Timothy; Benna, Mehdi; Franz, Heather; Bower, Hannah; Brunner, Anna; Blau, Hannah; Boucher, Thomas; Carmosino, Marco; Atreya, Sushil; Elliott, Harvey; Halleaux, Douglas; Rennó, Nilton; Wong, Michael; Pepin, Robert; Elliott, Beverley; Spray, John; Thompson, Lucy; Gordon, Suzanne; Newsom, Horton; Ollila, Ann; Williams, Joshua; Vasconcelos, Paulo; Bentz, Jennifer; Nealson, Kenneth; Popa, Radu; Kah, Linda C.; Moersch, Jeffrey; Tate, Christopher; Day, Mackenzie; Kocurek, Gary; Hallet, Bernard; Sletten, Ronald; Francis, Raymond; McCullough, Emily; Cloutis, Ed; ten Kate, Inge Loes; Kuzmin, Ruslan; Arvidson, Raymond; Fraeman, Abigail; Scholes, Daniel; Slavney, Susan; Stein, Thomas; Ward, Jennifer; Berger, Jeffrey; Moores, John E.

    2014-01-01

    The Radiation Assessment Detector (RAD) on the Mars Science Laboratory's Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose equivalent from galactic cosmic rays and solar energetic particles on the martian surface for ~300 days of observations during the current solar maximum. These measurements provide insight into the radiation hazards associated with a human mission to the surface of Mars and provide an anchor point with which to model the subsurface radiation environment, with implications for microbial survival times of any possible extant or past life, as well as for the preservation of potential organic biosignatures of the ancient martian environment.

  2. Mars' surface radiation environment measured with the Mars Science Laboratory's Curiosity rover.

    Science.gov (United States)

    Hassler, Donald M; Zeitlin, Cary; Wimmer-Schweingruber, Robert F; Ehresmann, Bent; Rafkin, Scot; Eigenbrode, Jennifer L; Brinza, David E; Weigle, Gerald; Böttcher, Stephan; Böhm, Eckart; Burmeister, Soenke; Guo, Jingnan; Köhler, Jan; Martin, Cesar; Reitz, Guenther; Cucinotta, Francis A; Kim, Myung-Hee; Grinspoon, David; Bullock, Mark A; Posner, Arik; Gómez-Elvira, Javier; Vasavada, Ashwin; Grotzinger, John P

    2014-01-24

    The Radiation Assessment Detector (RAD) on the Mars Science Laboratory's Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose equivalent from galactic cosmic rays and solar energetic particles on the martian surface for ~300 days of observations during the current solar maximum. These measurements provide insight into the radiation hazards associated with a human mission to the surface of Mars and provide an anchor point with which to model the subsurface radiation environment, with implications for microbial survival times of any possible extant or past life, as well as for the preservation of potential organic biosignatures of the ancient martian environment.

  3. Levels of surface contamination with radioactive materials at workplaces of nuclear research centre at Rez

    International Nuclear Information System (INIS)

    Hoelgye, Z.; Nemcova, I.; Kasikova, M.; Popper, J.; Chysky, J.

    1983-01-01

    A hygiene supervision unit at workplaces of the nuclear Research Institute in Rez monitored on a long-term basis surface contamination with radioactive substances. Surface contamination was found at workplaces with open sources. Of the 4343 monitored places action levels were only exceeded in 13 cases. The obtained data were used for typifying workplaces with the highest level of surface contamination, to determine in certain instances the mechanism of the escape of radioactive substances from insulating facilities and to determine the rate of the spread of the radioactive substance into adjacent non-active workplaces. (author)

  4. Behavior of Rydberg atoms at surfaces: energy level shifts and ionization

    Energy Technology Data Exchange (ETDEWEB)

    Dunning, F.B. E-mail: fbd@rice.edu; Dunham, H.R.; Oubre, C.; Nordlander, P

    2003-04-01

    The ionization of xenon atoms excited to the extreme red and blue states in high-lying Xe(n) Stark manifolds at a metal surface is investigated. The data show that, despite their very different initial spatial characteristics, the extreme members of a given Stark manifold ionize at similar atom/surface separations. This is explained, with the aid of complex scaling calculations, in terms of the strong perturbations in the energies and structure of the atomic states induced by the presence of the surface which lead to avoided crossings between neighboring levels as the surface is approached.

  5. Behavior of Rydberg atoms at surfaces: energy level shifts and ionization

    CERN Document Server

    Dunning, F B; Oubre, C D; Nordlander, P

    2003-01-01

    The ionization of xenon atoms excited to the extreme red and blue states in high-lying Xe(n) Stark manifolds at a metal surface is investigated. The data show that, despite their very different initial spatial characteristics, the extreme members of a given Stark manifold ionize at similar atom/surface separations. This is explained, with the aid of complex scaling calculations, in terms of the strong perturbations in the energies and structure of the atomic states induced by the presence of the surface which lead to avoided crossings between neighboring levels as the surface is approached.

  6. The role of surface and subsurface processes in keeping pace with sea level rise in intertidal wetlands of Moreton Bay, Queensland, Australia

    Science.gov (United States)

    Lovelock, Catherine E.; Bennion, Vicki; Grinham, Alistair; Cahoon, Donald R.

    2011-01-01

    Increases in the elevation of the soil surfaces of mangroves and salt marshes are key to the maintenance of these habitats with accelerating sea level rise. Understanding the processes that give rise to increases in soil surface elevation provides science for management of landscapes for sustainable coastal wetlands. Here, we tested whether the soil surface elevation of mangroves and salt marshes in Moreton Bay is keeping up with local rates of sea level rise (2.358 mm y-1) and whether accretion on the soil surface was the most important process for keeping up with sea level rise. We found variability in surface elevation gains, with sandy areas in the eastern bay having the highest surface elevation gains in both mangrove and salt marsh (5.9 and 1.9 mm y-1) whereas in the muddier western bay rates of surface elevation gain were lower (1.4 and -0.3 mm y-1 in mangrove and salt marsh, respectively). Both sides of the bay had similar rates of surface accretion (~7–9 mm y-1 in the mangrove and 1–3 mm y-1 in the salt marsh), but mangrove soils in the western bay were subsiding at a rate of approximately 8 mm y-1, possibly due to compaction of organic sediments. Over the study surface elevation increments were sensitive to position in the intertidal zone (higher when lower in the intertidal) and also to variation in mean sea level (higher at high sea level). Although surface accretion was the most important process for keeping up with sea level rise in the eastern bay, subsidence largely negated gains made through surface accretion in the western bay indicating a high vulnerability to sea level rise in these forests.

  7. Predictors of gender achievement in physical science at the secondary level

    Science.gov (United States)

    Kozlenko, Brittany Hunter

    This study used the 2009 National Assessment of Educational Progress (NAEP) science restricted data-set for twelfth graders. The NAEP data used in this research study is derived from a sample group of 11,100 twelfth grade students that represented a national population of over 3,000,000 twelfth grade students enrolled in science in the United States in 2009. The researcher chose the NAEP data set because it provided a national sample using uniform questions. This study investigated how the factors of socioeconomic status (SES), parental education level, mode of instruction, and affective disposition affect twelfth grade students' physical science achievement levels in school for the sample population and subgroups for gender. The factors mode of instruction and affective disposition were built through factor analysis based on available questions from the student surveys. All four factors were found to be significant predictors of physical science achievement for the sample population. NAEP exams are administered to a national sample that represents the population of American students enrolled in public and private schools. This was a non-experimental study that adds to the literature on factors that impact physical science for both genders. A gender gap is essentially nonexistent at the fourth grade level but appears at the eighth grade level in science based on information from NAEP (NCES, 1997). The results of the study can be used to make recommendation for policy change to diminish this gender gap in the future. Educators need to be using research to make instructional decisions; research-based instruction helps all students.

  8. Probing the Natural World, Level III, Teacher's Edition: Investigating Variation. Intermediate Science Curriculum Study.

    Science.gov (United States)

    Bonar, John R., Ed.; Hathway, James A., Ed.

    This is the teacher's edition of one of the eight units of the Intermediate Science Curriculum Study (ISCS) for level III students (grade 9). This unit focuses on diversity in human populations, measurement, and data collection. Optional excursions are described for students who wish to study a topic in greater depth. An introduction describes…

  9. Probing the Natural World, Level III, Student Guide: Investigating Variation. Intermediate Science Curriculum Study.

    Science.gov (United States)

    Bonar, John R., Ed.; Hathway, James A., Ed.

    This is the student's text of one unit of the Intermediate Science Curriculum Study (ISCS) for level III students (grade 9). This unit focuses on diversity in human populations, measurement, and data collection. Numerous activities are given and optional excursions encourage students to pursue a topic in greater depth. Data tables within the…

  10. Endorsing the Practical Endorsement? OCR's Approach to Practical Assessment in Science A-Levels

    Science.gov (United States)

    Evans, Steve; Wade, Neil

    2015-01-01

    This article summarises the practical requirements for new science A-levels in biology, chemistry and physics for first teaching from September 2015. It discusses the background to how the new approach was reached and how OCR has seen this taking shape in our assessment models. The opportunities presented by this new approach to practical…

  11. Pre-Service Teachers' Knowledge and Teaching Comfort Levels for Agricultural Science and Technology Objectives

    Science.gov (United States)

    Wingenbach, Gary J.; White, Judith McIntosh; Degenhart, Shannon; Pannkuk, Tim; Kujawski, Jenna

    2007-01-01

    Self-efficacy beliefs are defined as context-specific assessments of one's competence to perform specific tasks, influence one's efforts, persistence, and resilience to succeed in a given task. Such beliefs are important determinants when considering agricultural science teachers' subject matter knowledge, teaching comfort levels, and their…

  12. The Level and Quality of Accountability Talk in the Science Lessons

    Science.gov (United States)

    Motlhabane, Abraham

    2016-01-01

    Teachers are actively encouraged to plan their lessons such that there is maximum classroom talk, namely accountability talk. However, many lessons do not display sufficient accountability talk. This study attempted to better understand the level and quality of accountability talk in six science lessons. The study aimed to provide teachers with…

  13. Swiss and Turkish Pre-Service Science Teachers' Anxiety Levels for Educational Technology

    Science.gov (United States)

    Efe, Hulya Aslan; Efe, Rifat

    2016-01-01

    This study aims to culturally explain pre-service science teachers' instructional technology-related anxiety levels by analyzing the variables of their instructional technology using experiences, frequency of using instructional technologies, access to instructional technologies, instructional technology-related attitude and their instructional…

  14. Applied Math & Science Levels Utilized in Selected Trade & Industrial Vocational Education. Final Report.

    Science.gov (United States)

    Gray, James R.

    Research identified and evaluated the level of applied mathematics and science used in selected trade and industrial (T&I) subjects taught in the Kentucky Vocational Education System. The random sample was composed of 52 programs: 21 carpentry, 20 electricity/electronics, and 11 machine shop. The 96 math content items that were identified as…

  15. Validating Performance Level Descriptors (PLDs) for the AP® Environmental Science Exam

    Science.gov (United States)

    Reshetar, Rosemary; Kaliski, Pamela; Chajewski, Michael; Lionberger, Karen

    2012-01-01

    This presentation summarizes a pilot study conducted after the May 2011 administration of the AP Environmental Science Exam. The study used analytical methods based on scaled anchoring as input to a Performance Level Descriptor validation process that solicited systematic input from subject matter experts.

  16. Combining Geography, Math, and Science to Teach Climate Change and Sea Level Rise

    Science.gov (United States)

    Oldakowski, Ray; Johnson, Ashley

    2018-01-01

    This study examines the effectiveness of integrating geography into existing math and science curriculum to teach climate change and sea level rise. The desired outcome is to improve student performance in all three subjects. A sample of 120 fifth graders from three schools were taught the integrated curriculum over a period of two to three weeks.…

  17. Probing the Natural World, Level III, Student Guide: What's Up? Intermediate Science Curriculum Study.

    Science.gov (United States)

    Bonar, John R., Ed.; Hathway, James A., Ed.

    This is the student's text of one unit of the Intermediate Science Curriculum Study (ISCS) for level III students (grade 9). The chapters contain basic information about rockets, space, and principles of physics, as well as activities related to the subject and optional excursions. A section of introductory notes to the student discusses how the…

  18. The New Horizons Radio Science Experiment: Performance and Measurements of Pluto's Atmospheric Structure, Surface Pressure, and Surface Temperature

    Science.gov (United States)

    Linscott, I.; Hinson, D. P.; Bird, M. K.; Stern, A.; Weaver, H. A., Jr.; Olkin, C.; Young, L. A.; Ennico Smith, K.

    2015-12-01

    The New Horizons (NH) spacecraft payload contained the Radio Science Experiment (REX) for determining key characteristics of Pluto and Charon during the July 14, 2015, flyby of the Pluto/Charon system. The REX flight equipment augments the NH X-band radio transceiver by providing a high precision, narrow band recording of high power uplink transmissions from Earth stations, as well as a record of broadband radiometric power. This presentation will review the performance and initial results of two high- priority observations. First, REX received two pair of 20-kW signals, one pair per polarization, transmitted from the DSN at 4.2-cm wavelength during a diametric radio occultation by Pluto. REX recorded these uplink signals and determined precise measurement of the surface pressure, the temperature structure of the lower atmosphere, and the surface radius of Pluto. The ingress portion of one polarization was played back from the spacecraft in July and processed to obtain the pressure and temperature structure of Pluto's atmosphere. Second, REX measured the thermal emission from Pluto at 4.2- cm wavelength during two linear scans across the disk at close range when both the dayside and the night side are visible. Both scans extend from limb to limb with a resolution of one-tenth Pluto's disk and temperature resolution of 0.1 K. Occultation and radiometric temperature results presented here will encompass additional data scheduled for playback in September.

  19. Using a dynamic, introductory-level volcanoes class as a means to introduce non-science majors to the geosciences

    Science.gov (United States)

    Cook, G. W.

    2012-12-01

    itself—I take the opportunity in the first two weeks to introduce students to basic geology, including tectonics, earth materials, surface processes, and geologic time. In fact, this is a vital segment of the class, as the students need this background for the latter portions of the class. A side benefit is that students are provided with a "mini" education in geology whether they know it or not and take this knowledge with them into other classes, and ultimately, their futures. Student satisfaction is uniformly very high with this class. 100% of students agreed that the course material was intellectually stimulating; 95% of students agreed that they learned a great deal from the course; 100% of students stated that they would recommend the class to other students. Overall, the class highlights the role that non-major introductory-level geoscience classes, in particular ones with interesting topics, can serve in educating college-level students about Earth Science. They may also serve as a gateway into the Earth Sciences for students who previously had no such inclination.

  20. Molecular-level chemistry of model single-crystal oxide surfaces with model halogenated compounds

    Science.gov (United States)

    Adib, Kaveh

    Synchrotron-based X-ray photoelectron spectroscopy (XPS), temperature-programmed desorption (TPD) and low energy electron diffraction (LEED) have been used to investigate, at a molecular level, the chemistry of different terminations of single crystal iron-oxide surfaces with probe molecules (CCl4 and D2O). Comparisons of the reactivity of these surfaces towards CCl4, indicate that the presence of an uncapped surface Fe cation (strong Lewis acid site) and an adjacent oxygen site capped by that cation can effect the C-Cl bond cleavage in CCl4, resulting in dissociatively adsorbed Cl-adatoms and carbon-containing fragments. If in addition to these sites, an uncapped surface oxygen (Lewis base) site is also available, the carbon-containing moiety can then move that site, coordinate itself with that uncapped oxygen, and stabilize itself. At a later step, the carbon-containing fragment may form a strong covalent bond with the uncapped oxygen and may even abstract that surface oxygen. On the other hand, if an uncapped oxygen is not available to stabilize the carbon-containing fragment, the surface coordination will not occur and upon the subsequent thermal annealing of the surface the Cl-adatoms and the carbon-containing fragments will recombine and desorb as CCl4. Finally, the presence of surface deuteroxyls blocking the strong Lewis acid and base sites of the reactive surface, passivates this surface. Such a deuteroxylated surface will be unreactive towards CCl 4. Such a molecular level understanding of the surface chemistry of metal-oxides will have applications in the areas of selective catalysis, including environmental catalysis, and chemical sensor technology.

  1. Monitoring sea level and sea surface temperature trends from ERS satellites

    DEFF Research Database (Denmark)

    Andersen, Ole Baltazar; Knudsen, Per; Beckley, B.

    2002-01-01

    Data from the two ESA satellites ERS-1 and ERS-2 are used in global and regional analysis of sea level and sea surface temperature trends over the last, 7.8 years. T he ERS satellites and in the future the ENVISAT satellite provide unique opportunity for monitoring both changes in sea level and sea...

  2. Increasing Resilience Through Engagement In Sea Level Rise Community Science Initiatives.

    Science.gov (United States)

    Chilton, L. A.; Rindge, H.

    2017-12-01

    Science literate and engaged members of the public, including students, are critical to building climate resilient communities. USC Sea Grant facilitates programs that work to build and strengthen these connections. The Urban Tides Community Science Initiative (Urban Tides) and the Youth Exploring Sea Level Rise Science Program (YESS) engage communities across the boundaries of public engagement, K-12 education, and informal education. YESS is an experiential sea level rise education program that combines classroom learning, field investigations and public presentations. Students explore sea level rise using a new curricula, collect their own data on sea level rise, develop communication products, and present their findings to city governments, researchers, and others. Urban Tides engages community members, informal education centers, K-12 students, and local government leaders in a citizen science program photo- documenting extreme high tides, erosion and coastal flooding in Southern California. Images provide critical information to help calibrate scientific models used to identify locations vulnerable to damage from future sea level rise. These tools and information enable community leaders and local governments to set priorities, guidelines, and update policies as they plan strategies that will help the region adapt. The program includes a mobile app for data collection, an open database to view photos, a lesson plan, and community beach walks. Urban Tides has led to an increase in data and data-gathering capacity for regional scientists, an increase in public participation in science, and an increase in ocean and climate literacy among initiative participants. Both of these programs bring informed and diverse voices into the discussion of how to adapt and build climate resilient communities. USC Sea Grant will share impacts and lessons learned from these two unique programs.

  3. Conceptualizing Student Affect for Science and Technology at the Middle School Level: Development and Implementation of a Measure of Affect in Science and Technology (MAST)

    Science.gov (United States)

    Romine, William L.; Sadler, Troy D.; Wulff, Eric P.

    2017-10-01

    We describe the development of the Measure of Affect in Science and Technology (MAST), and study its usefulness for measuring science affect in middle school students via both classical and Rasch measurement perspectives. We then proceed to utilize the measurement structure of the MAST to understand how middle school students at varying levels of affect express their interest and attitudes toward science and technology and gender differences in how students express their affect. We found that affect in science and technology comprises a main dimension, science interest, and four peripheral dimensions: interest in careers in science and technology, attitudes toward science, and interest in attending science class. Of these, careers in science and technology carry the highest affective demand. While males showed higher levels of personal and situational interest in science, a greater interest in careers in science and technology was the biggest contributor to males' higher affect toward science and technology. We argue that whether the MAST is used as a measure of a single construct or multiple subconstructs depends upon specific research or evaluation goals; however, both uses of the MAST yield measures which produce valid inferences for student affect.

  4. Lake Storage Measurements For Water Resources Management: Combining Remotely Sensed Water Levels and Surface Areas

    Science.gov (United States)

    Brakenridge, G. R.; Birkett, C. M.

    2013-12-01

    Presently operating satellite-based radar altimeters have the ability to monitor variations in surface water height for large lakes and reservoirs, and future sensors will expand observational capabilities to many smaller water bodies. Such remote sensing provides objective, independent information where in situ data are lacking or access is restricted. A USDA/NASA (http://www.pecad.fas.usda.gov/cropexplorer/global_reservoir/) program is performing operational altimetric monitoring of the largest lakes and reservoirs around the world using data from the NASA/CNES, NRL, and ESA missions. Public lake-level products from the Global Reservoir and Lake Monitor (GRLM) are a combination of archived and near real time information. The USDA/FAS utilizes the products for assessing international irrigation potential and for crop production estimates; other end-users study climate trends, observe anthropogenic effects, and/or are are involved in other water resources management and regional water security issues. At the same time, the Dartmouth Flood Observatory (http://floodobservatory.colorado.edu/), its NASA GSFC partners (http://oas.gsfc.nasa.gov/floodmap/home.html), and associated MODIS data and automated processing algorithms are providing public access to a growing GIS record of the Earth's changing surface water extent, including changes related to floods and droughts. The Observatory's web site also provide both archival and near real time information, and is based mainly on the highest spatial resolution (250 m) MODIS bands. Therefore, it is now possible to provide on an international basis reservoir and lake storage change measurements entirely from remote sensing, on a frequently updating basis. The volume change values are based on standard numerical procedures used for many decades for analysis of coeval lake area and height data. We provide first results of this combination, including prototype displays for public access and data retrieval of water storage

  5. Surface core level shifts of clean and oxygen covered Ir(111)

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, M; Cassese, D; Cavallin, A; Comin, R; Orlando, F; Postregna, L [Universita degli Studi di Trieste, Via A Valerio 2, 34127, Trieste (Italy); Golfetto, E; Baraldi, A [Dipartimento di Fisica e CENMAT, Universita degli Studi di Trieste, Via A Valerio 2, 34127, Trieste (Italy); Lizzit, S [Sincrotrone Trieste S.C.p.A., S.S. 14 Km 163.5, 34012 Trieste (Italy)], E-mail: alessandro.baraldi@elettra.trieste.it

    2009-06-15

    We present the results of high resolution core level photoelectron spectroscopy employed to investigate the electronic structure of clean and oxygen covered Ir(111) surface. Ir 4f{sub 7/2} core level spectra are shown to be very sensitive to the local atomic environment. For the clean surface we detected two distinct components shifted by 550 meV, originated by surface and bulk atoms. The larger Gaussian width of the bulk component is explained as due to experimentally unresolved subsurface components. In order to determine the relevance of the phonon contribution we examined the thermal behaviour of the core level lineshape using the Hedin-Rosengren theory. From the phonon-induced spectral broadening we found the Debye temperature of bulk and surface atoms to be 298 and 181 K, respectively, which confirms the softening of the vibrational modes at the surface. Oxygen adsorption leads to the appearance of new surface core level components at -200 meV and +230 meV, which are interpreted as due to first-layer Ir atoms differently coordinated with oxygen. The coverage dependence of these components demonstrates that the oxygen saturation corresponds to 0.38 ML, in good agreement with recent density functional theory calculations.

  6. Research on near-surface disposal of very low level radioactive waste

    International Nuclear Information System (INIS)

    Wang Shaowei; Yue Huiguo; Hou Jie; Chen Haiying; Zuo Rui; Wang Jinsheng

    2012-01-01

    Radioactive waste disposal is one of the most sensitive environmental problems to control and solve. As the arriving of decommissioning of early period nuclear facilities in China, large amounts of very low level radioactive waste will be produced inevitably. The domestic and abroad definitions about very low level radioactive waste and its disposal were introduced, and then siting principles of near-surface disposal of very low level radioactive waste were discussed. The near- surface disposal siting methods of very low level radioactive waste were analyzed from natural and geographical conditions assessment, geological conditions analysis, hydrogeological conditions analysis, geological hazard assessment and radioactive background investigation; the near-surface disposal sites'natural barriers of very low level radioactive waste were analyzed from the crustal structure and physico-chemical characteristics, the dynamics characteristics of groundwater, the radionuclide adsorption characteristics of natural barriers and so on; the near-surface disposal sites' engineered barriers of very low level radioactive waste were analyzed from the repository design, the repository barrier materials selection and so on. Finally, the improving direction of very low level radioactive waste disposal was proposed. (authors)

  7. Two-Level Solutions to Exponentially Complex Problems in Glass Science

    DEFF Research Database (Denmark)

    Mauro, John C.; Smedskjær, Morten Mattrup

    Glass poses an especially challenging problem for physicists. The key to making progress in theoretical glass science is to extract the key physics governing properties of practical interest. In this spirit, we discuss several two-level solutions to exponentially complex problems in glass science....... Topological constraint theory, originally developed by J.C. Phillips, is based on a two-level description of rigid and floppy modes in a glass network and can be used to derive quantitatively accurate and analytically solvable models for a variety of macroscopic properties. The temperature dependence...... that captures both primary and secondary relaxation modes. Such a model also offers the ability to calculate the distinguishability of particles during glass transition and relaxation processes. Two-level models can also be used to capture the distribution of various network-forming species in mixed...

  8. Manufacturing microsystems-on-a-chip with 5-level surface micromachining technology

    Energy Technology Data Exchange (ETDEWEB)

    Sniegowski, J.; Rodgers, M.S.

    1998-05-01

    An agile microsystem manufacturing technology has been developed that provides unprecedented 5 levels of independent polysilicon surface-micromachine films for the designer. Typical surface-micromachining processes offer a maximum of 3 levels, making this the most complex surface-micromachining process technology developed to date. Leveraged from the extensive infrastructure present in the microelectronics industry, the manufacturing method of polysilicon surface-micromachining offers similar advantages of high-volume, high-reliability, and batch-fabrication to microelectromechanical systems (MEMS) as has been accomplished with integrated circuits (ICs). These systems, comprised of microscopic-sized mechanical elements, are laying the foundation for a rapidly expanding, multi-billion dollar industry 2 which impacts the automotive, consumer product, and medical industries to name only a few.

  9. A Science Faculty's Transformation of Nature of Science Understanding into His Teaching Graduate Level Chemistry Course

    Science.gov (United States)

    Aydin, Sevgi

    2015-01-01

    This is an interpretive case study to examine the teaching of an experienced science faculty who had a strong interest in teaching undergraduate and graduate science courses and nature of science specifically. It was interested in how he transformed knowledge from his experience as a scientist and his ideas about nature of science into forms…

  10. On the Application of Science Systems Engineering and Uncertainty Quantification for Ice Sheet Science and Sea Level Projections

    Science.gov (United States)

    Schlegel, Nicole-Jeanne; Boening, Carmen; Larour, Eric; Limonadi, Daniel; Schodlok, Michael; Seroussi, Helene; Watkins, Michael

    2017-04-01

    Research and development activities at the Jet Propulsion Laboratory (JPL) currently support the creation of a framework to formally evaluate the observational needs within earth system science. One of the pilot projects of this effort aims to quantify uncertainties in global mean sea level rise projections, due to contributions from the continental ice sheets. Here, we take advantage of established uncertainty quantification tools embedded within the JPL-University of California at Irvine Ice Sheet System Model (ISSM). We conduct sensitivity and Monte-Carlo style sampling experiments on forward simulations of the Greenland and Antarctic ice sheets. By varying internal parameters and boundary conditions of the system over both extreme and credible worst-case ranges, we assess the impact of the different parameter ranges on century-scale sea level rise projections. The results inform efforts to a) isolate the processes and inputs that are most responsible for determining ice sheet contribution to sea level; b) redefine uncertainty brackets for century-scale projections; and c) provide a prioritized list of measurements, along with quantitative information on spatial and temporal resolution, required for reducing uncertainty in future sea level rise projections. Results indicate that ice sheet mass loss is dependent on the spatial resolution of key boundary conditions - such as bedrock topography and melt rates at the ice-ocean interface. This work is performed at and supported by the California Institute of Technology's Jet Propulsion Laboratory. Supercomputing time is also supported through a contract with the National Aeronautics and Space Administration's Cryosphere program.

  11. The level of new science leadership behaviors of school principals: A scale development

    Directory of Open Access Journals (Sweden)

    Akpil Şerife

    2016-01-01

    Full Text Available Einstein’s theory of relativity and quantum physics opened Newton physics up for discussion, thus triggering the new science at the beginning of the 20th century. Philosophy of science, which was named as the new science in the 20th century, caused fundamental changes in research methods and paradigms. The methods and set of values brought by the new science affected social sciences as well. In conjunction with this mentioned change and development, the field of education and the view of schools were influenced. In the same vein, identifying the thoughts of school principals on leadership styles based on new science was considered as a primary need and set the objective of this research. In this regard, a “The Levels of New Science Leadership Behaviors of School Principals Scale” was developed. Following the literature review, the scale with 54 items was prepared and underwent expert review. Finally it was applied to 200 school principals who were working in primary and secondary schools in the Anatolian side of Istanbul. The data acquired were analyzed through SPSS 15.0 and Lisrel 8.51 programs. The results of the analysis revealed that the scale was comprised of a total of 27 items and had 5 factors (dimensions. The reliability analysis indicated internal consistency value (Cronbach Alpha as .94. Confirmatory factor analysis was carried out in Lisrel program. According to results of confirmatory factor analysis, the X2/df ratio was calculated as 2, 24 which showed that the measurement model was in accord with the data.

  12. Density functionals for surface science: Exchange-correlation model development with Bayesian error estimation

    DEFF Research Database (Denmark)

    Wellendorff, Jess; Lundgård, Keld Troen; Møgelhøj, Andreas

    2012-01-01

    A methodology for semiempirical density functional optimization, using regularization and cross-validation methods from machine learning, is developed. We demonstrate that such methods enable well-behaved exchange-correlation approximations in very flexible model spaces, thus avoiding the overfit......A methodology for semiempirical density functional optimization, using regularization and cross-validation methods from machine learning, is developed. We demonstrate that such methods enable well-behaved exchange-correlation approximations in very flexible model spaces, thus avoiding...... the energetics of intramolecular and intermolecular, bulk solid, and surface chemical bonding, and the developed optimization method explicitly handles making the compromise based on the directions in model space favored by different materials properties. The approach is applied to designing the Bayesian error...... sets validates the applicability of BEEF-vdW to studies in chemistry and condensed matter physics. Applications of the approximation and its Bayesian ensemble error estimate to two intricate surface science problems support this....

  13. Influence of surface pre-treatment on the electronic levels in silicon MaWCE nanowires.

    Science.gov (United States)

    Venturi, Giulia; Castaldini, Antonio; Schleusener, Alexander; Sivakov, Vladimir; Cavallini, Anna

    2015-05-15

    Deep level transient spectroscopy (DLTS) was performed on n-doped silicon nanowires grown by metal-assisted wet chemical etching (MaWCE) with gold as the catalyst in order to investigate the energetic scheme inside the bandgap. To observe the possible dependence of the level scheme on the processing temperature, DLTS measurements were performed on the nanowires grown on a non-treated Au/Si surface and on a thermally pre-treated Au/Si surface. A noticeable modification of the configuration of the energy levels was observed, induced by the annealing process. Based on our results on these MaWCE nanowires and on literature data about deep levels in bulk silicon, some hypotheses were advanced regarding the identification of the defects responsible of the energy levels revealed.

  14. Evidence of The Importance of Philosophy of Science Course On Undergraduate Level

    Science.gov (United States)

    Suyono

    2018-01-01

    This study aimed to describe academic impact of Philosophy of Science course in change of students’ conceptions on the Nature of science (NOS) before and after attending the course. This study followed one group pretest-posttest design. Treatment in this study was Philosophy of Science course for one semester. Misconception diagnostic tests of the NOS had been developed by Suyono et al. (2015) equipped with Certainty of Response Index (CRI). It consists of 15 concept questions about the NOS. The number of students who were tested on Chemistry Education Program (CEP) and Chemistry Program (CP) respectively 42 and 45 students. This study shows that after the learning of Philosophy of Science course happened: (1) the decrease of the number of misconception students on the NOS from 47.47 to 19.20% in CEP and from 47.47 to 18.18% in CP and (2) the decrease in the number of concepts that understood as misconception by the large number of students from 11 to 2 concepts on the CEP and from 10 to 2 concepts on CP. Therefore, the existence of Philosophy of Science course has a positive academic impact on students from both programs on undergraduate level.

  15. Classroom-based science research at the introductory level: changes in career choices and attitude.

    Science.gov (United States)

    Harrison, Melinda; Dunbar, David; Ratmansky, Lisa; Boyd, Kimberly; Lopatto, David

    2011-01-01

    Our study, focused on classroom-based research at the introductory level and using the Phage Genomics course as the model, shows evidence that first-year students doing research learn the process of science as well as how scientists practice science. A preliminary but notable outcome of our work, which is based on a small sample, is the change in student interest in considering different career choices such as graduate education and science in general. This is particularly notable, as previous research has described research internships as clarifying or confirming rather than changing undergraduates' decisions to pursue graduate education. We hypothesize that our results differ from previous studies of the impact of engaging in research because the students in our study are still in the early stages of their undergraduate careers. Our work builds upon the classroom-based research movement and should be viewed as encouraging to the Vision and Change in Undergraduate Biology Education movement advocated by the American Association for the Advancement of Science, the National Science Foundation, and other undergraduate education stakeholders.

  16. Gait Characteristics Associated with Trip-Induced Falls on Level and Sloped Irregular Surfaces

    Directory of Open Access Journals (Sweden)

    Andrew Merryweather

    2011-11-01

    Full Text Available Same level falls continue to contribute to an alarming number of slip/trip/fall injuries in the mining workforce. The objective of this study was to investigate how walking on different surface types and transverse slopes influences gait parameters that may be associated with a trip event. Gait analysis was performed for ten subjects on two orientations (level and sloped on smooth, hard surface (control and irregular (gravel, larger rocks surfaces. Walking on irregular surfaces significantly increased toe clearance compared to walking on the smooth surface. There was a significant (p < 0.05 decrease in cadence (steps/min, stride length (m, and speed (m/s from control to gravel to larger rocks. Significant changes in external rotation and increased knee flexion while walking on irregular surfaces were observed. Toe and heel clearance requirements increased on irregular surfaces, which may provide an explanation for trip-induced falls; however, the gait alterations observed in the experienced workers used as subjects would likely improve stability and recovery from a trip.

  17. Probability distribution for the Gaussian curvature of the zero level surface of a random function

    Science.gov (United States)

    Hannay, J. H.

    2018-04-01

    A rather natural construction for a smooth random surface in space is the level surface of value zero, or ‘nodal’ surface f(x,y,z)  =  0, of a (real) random function f; the interface between positive and negative regions of the function. A physically significant local attribute at a point of a curved surface is its Gaussian curvature (the product of its principal curvatures) because, when integrated over the surface it gives the Euler characteristic. Here the probability distribution for the Gaussian curvature at a random point on the nodal surface f  =  0 is calculated for a statistically homogeneous (‘stationary’) and isotropic zero mean Gaussian random function f. Capitalizing on the isotropy, a ‘fixer’ device for axes supplies the probability distribution directly as a multiple integral. Its evaluation yields an explicit algebraic function with a simple average. Indeed, this average Gaussian curvature has long been known. For a non-zero level surface instead of the nodal one, the probability distribution is not fully tractable, but is supplied as an integral expression.

  18. Correlation of Cell Surface Biomarker Expression Levels with Adhesion Contact Angle Measured by Lateral Microscopy.

    Science.gov (United States)

    Walz, Jenna A; Mace, Charles R

    2018-06-05

    Immunophenotyping is typically achieved using flow cytometry, but any influence a biomarker may have on adhesion or surface recognition cannot be determined concurrently. In this manuscript, we demonstrate the utility of lateral microscopy for correlating cell surface biomarker expression levels with quantitative descriptions of cell morphology. With our imaging system, we observed single cells from two T cell lines and two B cell lines adhere to antibody-coated substrates and quantified this adhesion using contact angle measurements. We found that SUP-T1 and CEM CD4+ cells, both of which express similar levels of CD4, experienced average changes in contact angle that were not statistically different from one another on surfaces coated in anti-CD4. However, MAVER-1 and BJAB K20 cells, both of which express different levels of CD20, underwent average changes in contact angle that were significantly different from one another on surfaces coated in anti-CD20. Our results indicate that changes in cell contact angles on antibody-coated substrates reflect the expression levels of corresponding antigens on the surfaces of cells as determined by flow cytometry. Our lateral microscopy approach offers a more reproducible and quantitative alternative to evaluate adhesion compared to commonly used wash assays and can be extended to many additional immunophenotyping applications to identify cells of interest within heterogeneous populations.

  19. Spatially-varying surface roughness and ground-level air quality in an operational dispersion model

    International Nuclear Information System (INIS)

    Barnes, M.J.; Brade, T.K.; MacKenzie, A.R.; Whyatt, J.D.; Carruthers, D.J.; Stocker, J.; Cai, X.; Hewitt, C.N.

    2014-01-01

    Urban form controls the overall aerodynamic roughness of a city, and hence plays a significant role in how air flow interacts with the urban landscape. This paper reports improved model performance resulting from the introduction of variable surface roughness in the operational air-quality model ADMS-Urban (v3.1). We then assess to what extent pollutant concentrations can be reduced solely through local reductions in roughness. The model results suggest that reducing surface roughness in a city centre can increase ground-level pollutant concentrations, both locally in the area of reduced roughness and downwind of that area. The unexpected simulation of increased ground-level pollutant concentrations implies that this type of modelling should be used with caution for urban planning and design studies looking at ventilation of pollution. We expect the results from this study to be relevant for all atmospheric dispersion models with urban-surface parameterisations based on roughness. -- Highlights: • Spatially variable roughness improved performance of an operational model. • Scenario modelling explored effect of reduced roughness on air pollution. • Reducing surface roughness can increase modelled ground-level pollution. • Damped vertical mixing outweighs increased horizontal advection in model study. • Result should hold for any model with a land-surface coupling based on roughness. -- Spatially varying roughness improves model simulations of urban air pollutant dispersion. Reducing roughness does not always decrease ground-level pollution concentrations

  20. Exploring the Self-Reported ICT Skill Levels of Undergraduate Science Students

    Directory of Open Access Journals (Sweden)

    Jef C. Verhoeven

    2015-12-01

    Full Text Available Computers have taken an important place in the training of science students and in the professional life of scientists. It is often taken for granted that most students have mastered basic Information and Communication Technologies (ICT skills; however, it has been shown that not all students are equally proficient in this regard. Starting from theories of socialization and technology acceptance we report how we constructed a structural equation model (SEM to explore the variance in the basic ICT skill levels of science students. We also present the results of a test of this model with university bachelor’s science students. Basic ICT skills were measured using a new, elaborate instrument allowing students to rate their skills in detail. Our results show that science students score high on basic ICT skills and that our SEM explains a large part of the variation in the ICT skill levels of these students. The most explanatory power is coming from four variables: the perceived ease of use and the perceived usefulness of a personal computer, the anxiety for using a personal computer, and students’ belief that ICT is necessary for scientific research.

  1. INTEGRATION OF BUSINESS, EDUCATION AND SCIENCE AT THE REGIONAL LEVEL FOR IMPLEMENTING THE NATIONAL TECHNOLOGICAL INITIATIVE

    Directory of Open Access Journals (Sweden)

    Innara Lyapina

    2018-01-01

    Full Text Available Current world affairs show that the post-industrial stage of development of all mature world powers’ economies is followed by creation of a new development paradigm, which is based on the economy of knowledge, science achievements, innovations, global information and communication systems, and which leads to innovative economy formation. In the context of the national innovation economy formation in the Russian Federation, prerequisites are created for integrating the efforts of business, science and education representatives to develop, produce and market high-tech products which have significant economic or social potential. And this is not only the task announced by the Russian government, but also a natural process in the country’s economy, which contributes to the increase in the integration participants’ efficiency. The result of such integrated interaction of education, science and business consists in a synergistic effect through formation of an interactive cooperation model that involves the active use of combined knowledge, ideas, technologies and other resources during innovative projects implementation. At the same time, integration processes are diverse, complex and occur in each case taking into account the integrating parties’ activity specifics. Within this framework, the goal of the research is to characterize the impact of the education, science and business integration process, on the national technological initiative implementation in the country on the whole and to study the integrating experience of these entities at the regional level. In the course of the research, the stages of the Russian national innovation economy formation process have been studied; the role of education, science and business in the National Technological Initiative implementation has been characterized; it’s been proved that educational institutions are the key link in the integration process in the chain “education – science

  2. Linguistic Resources Used in Grade 8 Students' Submicro Level Explanations—Science Items from TIMSS 2007

    Science.gov (United States)

    Frändberg, Birgitta; Lincoln, Per; Wallin, Anita

    2013-12-01

    Explanations involving submicro levels of representation are central to science education, but known to be difficult for students in secondary school. This study examines students' written explanations of physical and chemical phenomena regarding matter and changes in matter, in a large-scale test. This is done in order to understand linguistic challenges in constructing submicro level explanations involving the particle model of matter. Drawing from systemic functional linguistics, the lexicogrammatics used in explanations for realising experiential meaning in student explanations were analysed. We used answers to two partly constructed response items from the Swedish part of Trends in International Mathematics and Science Studies 2007, grade 8, to sort out explanations referring to the particle model of matter. These answers (86 from 954) were analysed regarding choices of vocabulary and grammar to distinguish between macro and submicro level of representation. The results show that students use a wide variety of lexicogrammatical resources to realise what happens on both macro and submicro level of representation, with greater diversity of verbs on the submicro level of explanation. The results suggest an uncertainty about the distinction between macro and submicro level of explanation.

  3. Atomic-level spatial distributions of dopants on silicon surfaces: toward a microscopic understanding of surface chemical reactivity

    Science.gov (United States)

    Hamers, Robert J.; Wang, Yajun; Shan, Jun

    1996-11-01

    We have investigated the interaction of phosphine (PH 3) and diborane (B 2H 6) with the Si(001) surface using scanning tunneling microscopy, infrared spectroscopy, and ab initio molecular orbital calculations. Experiment and theory show that the formation of PSi heterodimers is energetically favorable compared with formation of PP dimers. The stability of the heterodimers arises from a large strain energy associated with formation of PP dimers. At moderate P coverages, the formation of PSi heterodimers leaves the surface with few locations where there are two adjacent reactive sites. This in turn modifies the chemical reactivity toward species such as PH 3, which require only one site to adsorb but require two adjacent sites to dissociate. Boron on Si(001) strongly segregates into localized regions of high boron concentration, separated by large regions of clean Si. This leads to a spatially-modulated chemical reactivity which during subsequent growth by chemical vapor deposition (CVD) leads to formation of a rough surface. The implications of the atomic-level spatial distribution of dopants on the rates and mechanisms of CVD growth processes are discussed.

  4. Statistical analysis of global surface air temperature and sea level using cointegration methods

    DEFF Research Database (Denmark)

    Schmith, Torben; Johansen, Søren; Thejll, Peter

    Global sea levels are rising which is widely understood as a consequence of thermal expansion and melting of glaciers and land-based ice caps. Due to physically-based models being unable to simulate observed sea level trends, semi-empirical models have been applied as an alternative for projecting...... of future sea levels. There is in this, however, potential pitfalls due to the trending nature of the time series. We apply a statistical method called cointegration analysis to observed global sea level and surface air temperature, capable of handling such peculiarities. We find a relationship between sea...... level and temperature and find that temperature causally depends on the sea level, which can be understood as a consequence of the large heat capacity of the ocean. We further find that the warming episode in the 1940s is exceptional in the sense that sea level and warming deviates from the expected...

  5. Soil Moisture Active Passive (SMAP) Mission Level 4 Surface and Root Zone Soil Moisture (L4_SM) Product Specification Document

    Science.gov (United States)

    Reichle, Rolf H.; Ardizzone, Joseph V.; Kim, Gi-Kong; Lucchesi, Robert A.; Smith, Edmond B.; Weiss, Barry H.

    2015-01-01

    This is the Product Specification Document (PSD) for Level 4 Surface and Root Zone Soil Moisture (L4_SM) data for the Science Data System (SDS) of the Soil Moisture Active Passive (SMAP) project. The L4_SM data product provides estimates of land surface conditions based on the assimilation of SMAP observations into a customized version of the NASA Goddard Earth Observing System, Version 5 (GEOS-5) land data assimilation system (LDAS). This document applies to any standard L4_SM data product generated by the SMAP Project. The Soil Moisture Active Passive (SMAP) mission will enhance the accuracy and the resolution of space-based measurements of terrestrial soil moisture and freeze-thaw state. SMAP data products will have a noteworthy impact on multiple relevant and current Earth Science endeavors. These include: Understanding of the processes that link the terrestrial water, the energy and the carbon cycles, Estimations of global water and energy fluxes over the land surfaces, Quantification of the net carbon flux in boreal landscapes Forecast skill of both weather and climate, Predictions and monitoring of natural disasters including floods, landslides and droughts, and Predictions of agricultural productivity. To provide these data, the SMAP mission will deploy a satellite observatory in a near polar, sun synchronous orbit. The observatory will house an L-band radiometer that operates at 1.40 GHz and an L-band radar that operates at 1.26 GHz. The instruments will share a rotating reflector antenna with a 6 meter aperture that scans over a 1000 km swath.

  6. The Level of Utilizing Blended Learning in Teaching Science from the Point of View of Science Teachers in Private Schools of Ajman Educational Zone

    Science.gov (United States)

    Al-Derbashi, Khaled Y.; Abed, Osama H.

    2017-01-01

    This study aims to define the level of utilizing blended learning in teaching science from the point of view of science teachers (85 male and female teachers) who are working in private schools of Ajman Educational Zone. The study also aims to find if there are significant differences according to gender, years of experience, or the fact that…

  7. Conceptualizing Student Affect for Science and Technology at the Middle School Level: Development and Implementation of a Measure of Affect in Science and Technology (MAST)

    Science.gov (United States)

    Romine, William L.; Sadler, Troy D.; Wulff, Eric P.

    2017-01-01

    We describe the development of the Measure of Affect in Science and Technology (MAST), and study its usefulness for measuring science affect in middle school students via both classical and Rasch measurement perspectives. We then proceed to utilize the measurement structure of the MAST to understand how middle school students at varying levels of…

  8. The need for national diagnostic reference levels: entrance surface dose measurement in intraoral radiography

    International Nuclear Information System (INIS)

    Mortazavi, S. M. J.; Shareghi, A.; Kavousi, A.; Ghiassi-Nejad, M.; Jafari-Zadeh, M.; Nazeri, F.; Mozdarani, H.

    2004-01-01

    Background: Intraoral radiographies are the most frequent X-ray examinations in humans. According to International Commission on Radiation Protection recommendations, the selection of a diagnostic reference level should be specific to a country or region. Critical organs such as thyroid gland are exposed to X-rays in intraoral radiography and these exposures should be kept as low as reasonably achievable. To assist the development of DRLs for intraoral radiography, a National Radiation Protection Department-sponsored pilot study was carried out. Materials and methods: thermoluminescent dosimetry is widely acknowledged to be the recommended method for measuring entrance surface doses. In this study, entrance surface doses was measured using LiF thermoluminescent dosimeters on the skin (either mandibular or maxillary arcs) of 40 patients. Three thermoluminescent dosimetry chips were placed on the skin of each patient. The doses were averaged for each radiography and mean entrance surface doses of all patients calculated. Results: the mean ±SD entrance surface dose at the center of the beam on the patient's skin in intraoral radiography was 1.173 ±0.606 mGy (ranged from 0.01 o 0.40 m Gy). The mean entrance surface doses for male and female patients were 1.380± 0.823, and 1.004± 0.258 respectively. No statistically significant difference was found between these means. Despite its necessity , in national level , there is no published data on the diagnostic reference levels for intraoral radiography. However, the results obtained in this study are lower than those reported by investigators in other countries. Conclusion: in IR Iran , due to lack of large scale studies, no diagnostic reference levels have been set for X-ray diagnostic procedures. Due to lack of national diagnostic reference levels, it is not possible to clarify whether in intraoral radiographies any dose reduction techniques are needed. We intend to perform similar nationwide studies to set the

  9. Calculation of reasonable exemption levels for surface contamination by measuring overall gamma ray

    International Nuclear Information System (INIS)

    Ogino, Haruyuki; Hattori, Takatoshi

    2008-01-01

    The present regulation on surface contamination [Bq/cm 2 ] is determined from a simple radiological model for the most hazardous radionuclides (Pu-239 for alpha emitters and Sr-90 for beta emitters) and its extremely conservative model is applied for all other alpha and beta emitters. In this study, reasonable exemption levels for surface contamination are calculated for each radionuclide by adopting an original radiological dose evaluation method for surface contamination that can be applied in radiation safety, transport safety and waste safety. Furthermore, a new concept of judging the exemption by estimating the overall contamination [Bq] on the objects from the measurement of gamma ray has been designed and a reasonable value was derived. We conclude that the overall exemption levels obtained by gamma ray measurement can be one order smaller than those obtained by the conventional method for some radionuclides, such as Mn-54, Co-60, Nb-94, Cs-134, Cs-137, Eu-152 and Eu-154. (author)

  10. Alkyl-terminated Si(111) surfaces: A high-resolution, core level photoelectron spectroscopy study

    Energy Technology Data Exchange (ETDEWEB)

    Terry, J.; Linford, M.R.; Wigren, C.; Cao, R.; Pianetta, P.; Chidsey, C.E. [Stanford University, Stanford, California 94309 (United States)

    1999-01-01

    The bonding of alkyl monolayers to Si(111) surfaces has been studied with high-resolution core level photoelectron spectroscopy (PES). Two very different wet-chemical methods have been used to prepare the alkyl monolayers: (i) Olefin insertion into the H{endash}Si bond of the H{endash}Si(111) surface, and (ii) replacement of Cl on the Cl{endash}Si(111) surface by an alkyl group from an alkyllithium reagent. In both cases, PES has revealed a C 1s component shifted to lower binding energy and a Si 2p component shifted to higher binding energy. Both components are attributed to the presence of a C{endash}Si bond at the interface. Along with photoelectron diffraction data [Appl. Phys. Lett. {bold 71}, 1056, (1997)], these data are used to show that these two synthetic methods can be used to functionalize the Si(111) surface. {copyright} {ital 1999 American Institute of Physics.}

  11. The impact of accelerometer mounting methods on the level of vibrations recorded at ground surface

    Directory of Open Access Journals (Sweden)

    Krzysztof Czech

    2014-08-01

    Full Text Available The paper presents the results of field research based on the measurements of accelerations recorded at ground surface. The source of the vibration characterized by high repetition rate of pulse parameters was light falling weight deflectometer ZFG-01. Measurements of vibrations have been carried out using top quality high-precision measuring system produced by Brüel&Kiær. Accelerometers were mounted on a sandy soil surface at the measuring points located radially at 5-m and 10-m distances from the source of vibration. The paper analyses the impact that the method of mounting accelerometers on the ground has on the level of the recorded values of accelerations of vibrations. It has been shown that the method of attaching the sensor to the surface of the ground is crucial for the credibility of the performed measurements.[b]Keywords[/b]: geotechnics, surface vibrations, ground, vibration measurement

  12. Monitoring the variability of sea level and surface circulation with satellite altimetry

    NARCIS (Netherlands)

    Volkov, Denis L. "Jr"

    2004-01-01

    Variability in the ocean plays an important role in determining global weather and climate conditions. The advent of satellite altimetry has significantly facilitated the study of the variability of sea level and surface circulation. Satellites provide high-quality regular and nearly global

  13. Deep layer-resolved core-level shifts in the beryllium surface

    DEFF Research Database (Denmark)

    Aldén, Magnus; Skriver, Hans Lomholt; Johansson, Börje

    1993-01-01

    Core-level energy shifts for the beryllium surface region are calculated by means of a Green’s function technique within the tight-binding linear muffin-tin orbitals method. Both initial- and final-state effects in the core-ionization process are fully accounted for. Anomalously large energy shifts...

  14. Levels of Cd, Hg and Zn in some surface waters from the Eastern ...

    African Journals Online (AJOL)

    Total trace metals levels - Cd, Hg and Zn, which may affect human health and the "health" of the aquatic ecosystem, were determined in the Umtata, Buffalo, Keiskamma and Tyume Rivers and in the Sandile and Umtata Dams. These elements were also determined in sediment samples from some of these surface waters.

  15. Multiple-Choice Exams: An Obstacle for Higher-Level Thinking in Introductory Science Classes

    Science.gov (United States)

    Stanger-Hall, Kathrin F.

    2012-01-01

    Learning science requires higher-level (critical) thinking skills that need to be practiced in science classes. This study tested the effect of exam format on critical-thinking skills. Multiple-choice (MC) testing is common in introductory science courses, and students in these classes tend to associate memorization with MC questions and may not see the need to modify their study strategies for critical thinking, because the MC exam format has not changed. To test the effect of exam format, I used two sections of an introductory biology class. One section was assessed with exams in the traditional MC format, the other section was assessed with both MC and constructed-response (CR) questions. The mixed exam format was correlated with significantly more cognitively active study behaviors and a significantly better performance on the cumulative final exam (after accounting for grade point average and gender). There was also less gender-bias in the CR answers. This suggests that the MC-only exam format indeed hinders critical thinking in introductory science classes. Introducing CR questions encouraged students to learn more and to be better critical thinkers and reduced gender bias. However, student resistance increased as students adjusted their perceptions of their own critical-thinking abilities. PMID:22949426

  16. Statistical analysis of global surface temperature and sea level using cointegration methods

    DEFF Research Database (Denmark)

    Schmidt, Torben; Johansen, Søren; Thejll, Peter

    2012-01-01

    Global sea levels are rising which is widely understood as a consequence of thermal expansion and melting of glaciers and land-based ice caps. Due to the lack of representation of ice-sheet dynamics in present-day physically-based climate models being unable to simulate observed sea level trends......, semi-empirical models have been applied as an alternative for projecting of future sea levels. There is in this, however, potential pitfalls due to the trending nature of the time series. We apply a statistical method called cointegration analysis to observed global sea level and land-ocean surface air...... temperature, capable of handling such peculiarities. We find a relationship between sea level and temperature and find that temperature causally depends on the sea level, which can be understood as a consequence of the large heat capacity of the ocean. We further find that the warming episode in the 1940s...

  17. Serum levels of vitamin A, visual function and ocular surface after bariatric surgery

    Directory of Open Access Journals (Sweden)

    Luana Paula Nogueira de Araújo BRANDÃO

    Full Text Available ABSTRACT BACKGROUND Bariatric surgery is the most effective treatment for severe obesity, but the surgery increases the risk of developing nutritional deficiencies, such as vitamin A deficiency. In human metabolism, vitamin A plays a role in vision. OBJECTIVE To evaluate serum vitamin A, visual function and ocular surface of patients undergoing bariatric surgery. METHODS A cross-sectional and analytical study was conduced with 28 patients undergoing bariatric surgery for at least 6 months. Ophthalmologic evaluation was done through color vision test, contrast sensitivity test, ocular surface tests and confocal microscopy, as well as vitamin A serum measurement. RESULTS Vertical sleeve gastrectomy was performed in seven (25.0% patients and Roux -en-Y gastric by-pass in 21 (75.0%. Mean serum vitamin A level was 1.7±0.5 µmoL/L. Most patients (60.7% had symptoms of dry eye. Five (17.9% patients had contrast sensitivity impairment and 18 (64.3% color vision changes. In the group of patients undergoing Roux -en-Y gastric by-pass , mean vitamin A levels were 1.8±0.6 µmoL/L, whereas they were 1.7±0.5 µmoL/L in patients submitted to the restrictive technique vertical sleeve gastrectomy . The analysis of the influence of serum levels of vitamin A in the visual function and ocular surface was performed by Pearson correlation test and there was no significant correlation between any of the variables and vitamin A. CONCLUSION There was no influence of the bariatric surgery technique used on serum vitamin A levels, on the visual function or on the ocular surface. Moreover, there was no correlation between serum levels of vitamin A and the visual function or the ocular surface changes.

  18. Mars in Motion: An online Citizen Science platform looking for changes on the surface of Mars

    Science.gov (United States)

    Sprinks, James Christopher; Wardlaw, Jessica; Houghton, Robert; Bamford, Steven; Marsh, Stuart

    2016-10-01

    The European FP7 iMars project has developed tools and 3D models of the Martian surface through the co-registration of NASA and ESA mission data dating from the Viking missions of the 1970s to the present day, for a much more comprehensive interpretation of the geomorphological and climatic processes that have taken and do take place. We present the Citizen Science component of the project, 'Mars in Motion', created through the Zooniverse's Panoptes framework to allow volunteers to look for and identify changes on the surface of Mars over time. 'Mars in Motion', as with many other current citizen science platforms of a planetary or other disciplinary focus, has been developed to compliment the results of automated data mining analysis software, both by validation through the creation of training data and by adding context - gathering more in-depth data on the type and metrics of change initially detected.Through the analysis of initial volunteer results collected in the second half of 2016, the accuracy and ability of untrained participants to identify geomorphological changes is considered, as well as the impact of their position in the system. Volunteer contribution, either as a filter for poor quality imagery pre-algorithm, validation of algorithmic analysis, or adding context to pre-detected change, and their awareness and interpretation of its importance, can directly influence engagement with the platform and therefore ultimately its success. Understanding the effect of the volunteer and software's role in the system on both the results of and engagement with planetary science citizen science platforms will be an important lesson for the future, especially as the next generation of planetary missions will likely collect data orders of magnitude greater in volume. To deal with the data overload, it is likely that human or software solutions alone will not be sufficient, and that a combination of the two working together in a complimentary system that combines

  19. Preferences of lame cows for type of surface and level of social contact in hospital pens

    DEFF Research Database (Denmark)

    Jensen, Margit Bak; Herskin, Mette S; Thomsen, Peter T.

    2015-01-01

    To investigate preferences of lame cows for flooring and level of social contact, 37 lame, lactating dairy cows (diagnosed with sole ulcer or white line disease) were housed individually for 6 d in experimental hospital pens, where they could choose between 2 equally sized areas (6m × 4.5m......) with either deep-bedded sand or a rubber surface. On both surfaces, cows could choose between 2 equally sized areas either near or away from heifers in a neighboring group pen. Cows spent more time lying on the deep-bedded sand than on the rubber surface (870 vs. 71min/d), whereas they spent less time upright...... (standing or walking) on the sand than on the rubber surface (180 vs. 319min/d). In addition, cows spent less time self-grooming on the sand than on the rubber surface (2.2 vs. 4.7% of time spent upright). With regard to level of social contact, cows spent more time near the neighboring heifers than away...

  20. Severity of MIH findings at tooth surface level among German school children.

    Science.gov (United States)

    Petrou, M A; Giraki, M; Bissar, A-R; Wempe, C; Schäfer, M; Schiffner, U; Beikler, T; Schulte, A G; Splieth, C H

    2015-06-01

    This study was to investigate the distribution and clinical characteristics of teeth diagnosed with MIH at surface and defect type level in a cohort of German children. The study cohort included 242 children diagnosed with MIH which had been recorded during the compulsory dental school examinations of 20 German primary schools. The subjects had been enrolled by cluster sampling. All children attended the second to fourth grade (age 7-10 years, mean 8.1 ± 0.8). The children were examined by five calibrated examiners (kappa = 0.9) after tooth brushing. The recording comprised teeth, surfaces, type and severity of MIH defects and was conducted using a portable light, mirrors and cotton rolls. MIH was registered according to the EAPD criteria. Defects MIH defects at various surfaces of the same tooth were common. The number of affected tooth surfaces was positively correlated with the severity of MIH at child (p MIH teeth. The knowledge of the intra-oral distribution and severity of MIH findings at the enamel surface level is important for assessing the treatment needs.

  1. Developing science policy capacity at the state government level: Planning a science and technology policy fellowship program for Colorado and beyond

    Science.gov (United States)

    Druckenmiller, M. L.

    2017-12-01

    There is growing recognition of the potential to advance science policy capacity within state legislatures, where there is most often a shortage of professional backgrounds in the natural sciences, technology, engineering, and medicine. Developing such capacity at the state level should be considered a vital component of any comprehensive national scale strategy to strengthen science informed governance. Toward this goal, the Center for Science and Technology Policy Research at the University of Colorado Boulder is leading a strategic planning process for a Science and Technology Policy Fellowship Program within the Colorado state legislature and executive branch agencies. The intended program will place PhD-level scientists and engineers in one-year placements with decision-makers to provide an in-house resource for targeted policy-relevant research. Fellows will learn the intricacies of the state policymaking process, be exposed to opportunities for science to inform decisions, and develop a deeper understanding of key science and technology topics in Colorado, including water resources, wildfire management, and energy. The program's ultimate goals are to help foster a decision-making arena informed by evidence-based information, to develop new leaders adept at bridging science and policymaking realms, and to foster governance that champions the role of science in society. Parallel to efforts in Colorado, groups from nine other states are preparing similar plans, providing opportunities to share approaches across states and to set the stage for increased science and technology input to state legislative agendas nationwide. Importantly, highly successful and sustainable models exist; the American Association for the Advancement of Science (AAAS) has implemented a federally based fellowship program for over 43 years and the California Council for Science and Technology (CCST) has directed a fellowship program for their state's legislature since 2009. AAAS and CCST

  2. Country, School and Students Factors Associated with Extreme Levels of Science Literacy Across 25 Countries

    Science.gov (United States)

    Alivernini, F.; Manganelli, S.

    2015-08-01

    A huge gap in science literacy is between students who do not show the competencies that are necessary to participate effectively in life situations related to science and technology and students who have the skills which would give them the potential to create new technology. The objective of this paper is to identify, for 25 countries, distinct subgroups of students with characteristics that appear to be associated with this proficiency gap. Data were based on the answers of 46,131 PISA 2006 students with scores classified below level 2 or above level 4, as well as the answers of their principals to school questionnaire and the OECD indicators of the financial and human resources invested in education at the national level for secondary school. The dependent variable of the analysis was a dichotomous variable the values of which represent the two different groups of students. The independent variables were the OECD indicators, and the items and indices derived from the student and school questionnaires. The analysis was based on classification trees and the findings were replicated and extended by the means of a multilevel logistic regression model. The results show that very specific levels of teachers' salaries, parental pressure on schools, school size, awareness of environmental issues, science self-efficacy and socio-economic status have a very important role in predicting whether 15 year olds in OECD countries will belong to the lower or the highest proficiency groups as regards their aptitude in the context of life situations involving problems of a scientific nature.

  3. Mapping Hydrophobicity on the Protein Molecular Surface at Atom-Level Resolution

    Science.gov (United States)

    Nicolau Jr., Dan V.; Paszek, Ewa; Fulga, Florin; Nicolau, Dan V.

    2014-01-01

    A precise representation of the spatial distribution of hydrophobicity, hydrophilicity and charges on the molecular surface of proteins is critical for the understanding of the interaction with small molecules and larger systems. The representation of hydrophobicity is rarely done at atom-level, as this property is generally assigned to residues. A new methodology for the derivation of atomic hydrophobicity from any amino acid-based hydrophobicity scale was used to derive 8 sets of atomic hydrophobicities, one of which was used to generate the molecular surfaces for 35 proteins with convex structures, 5 of which, i.e., lysozyme, ribonuclease, hemoglobin, albumin and IgG, have been analyzed in more detail. Sets of the molecular surfaces of the model proteins have been constructed using spherical probes with increasingly large radii, from 1.4 to 20 Å, followed by the quantification of (i) the surface hydrophobicity; (ii) their respective molecular surface areas, i.e., total, hydrophilic and hydrophobic area; and (iii) their relative densities, i.e., divided by the total molecular area; or specific densities, i.e., divided by property-specific area. Compared with the amino acid-based formalism, the atom-level description reveals molecular surfaces which (i) present an approximately two times more hydrophilic areas; with (ii) less extended, but between 2 to 5 times more intense hydrophilic patches; and (iii) 3 to 20 times more extended hydrophobic areas. The hydrophobic areas are also approximately 2 times more hydrophobicity-intense. This, more pronounced “leopard skin”-like, design of the protein molecular surface has been confirmed by comparing the results for a restricted set of homologous proteins, i.e., hemoglobins diverging by only one residue (Trp37). These results suggest that the representation of hydrophobicity on the protein molecular surfaces at atom-level resolution, coupled with the probing of the molecular surface at different geometric resolutions

  4. Application of surface science to the study of the corrosion of PWR primary circuit materials

    International Nuclear Information System (INIS)

    Harris, S.J.

    1989-04-01

    This thesis describes a study of the corrosion and oxidation of PWR primary circuit materials using surface sensitive spectroscopic techniques. An X-ray photoemission spectroscopy (XPS) study of a number of mixed oxides of known composition is described and the information obtained is related to XPS measurements made on the surface of iron and nickel based alloys oxidised under controlled conditions. A secondary ion mass spectroscopy (SIMA) study on these mixed transition metal oxides is also described. The gaseous oxidation of stainless steel 3041 and Inconel-690 is examined. Both alloys were oxidised at 600K in air with the composition of the oxide films formed studied by a range of surface spectroscopic methods. Further experimental work was performed on Inconel-690 to examine the effects of surface pretreatment and the effects of low oxygen partial pressures on the formation of oxide films at 600 K. The incorporation of the radionuclide, cobalt-60, into the oxide films formed on structural components of a PWR, result in the build up of radiation fields. A method of pretreating the surface of the alloy stainless steel 3041, in order to reduce the level of cobalt adsorbed into the oxide film formed under simulated primary coolant conditions is examined and contrasts with treatments which have been developed to release cobalt adsorbed in existing oxide layers under reactor conditions are discussed. (author)

  5. Estimation of surface UV levels based on Meteor-3/TOMS ozone data

    Energy Technology Data Exchange (ETDEWEB)

    Borisov, Y A [Central Aerological Observatory, Moscow (Russian Federation); Geogdzhaev, I V [Moscow Inst. of Physics and Technology, Moscow (Russian Federation); Khattatov, V U [Central Aerological Observatory, Moscow (Russian Federation)

    1996-12-31

    The major consequence of ozone layer depletion for the environment is an increase of harmful ultraviolet (UV) radiation on the Earth surface and in the upper ocean. This implies the importance of environmental UV monitoring. Since the direct global monitoring is not currently possible, indirect estimations of surface UV levels may be used based on satellite ozone data (Madronich, S. 1992). Total Ozone Mapping Spectrometer (TOMS) on board the METEOR-3 satellite provided regular set of data for such estimates. During the time of its operation (August, 1991 - December, 1994) the instrument registered several ozone hole events over Antarctica, when ozone levels dropped by as much as 60 % from their unperturbed values. Probably even more alarming ozone depletions were observed over highly populated regions of middle latitudes of northern hemisphere. Radiative transfer modeling was used to convert METEOR-3/TOMS daily ozone values into regional and global maps of biologically active UV. Calculations demonstrate the effect on surface UV levels produced by ozone hole over Antarctica and ozone depletions over the territory of Russia (March, 1994). UV contour lines deviate from the normal appearance which is determined by growing southward solar elevation. UV contour lines are almost perpendicular to the ozone ones in the ozone depletions areas. The 30 % ozone depletion, over Siberia caused more than 30 % increase in noontime erythemal UV levels, which is equivalent to 10-15 degrees southward latitude displacement. Higher UV radiation increases were found in ozone hole over South America (October 1992) equivalent to about 20 degrees southward displacement

  6. Two Surface-Tension Formulations For The Level Set Interface-Tracking Method

    International Nuclear Information System (INIS)

    Shepel, S.V.; Smith, B.L.

    2005-01-01

    The paper describes a comparative study of two surface-tension models for the Level Set interface tracking method. In both models, the surface tension is represented as a body force, concentrated near the interface, but the technical implementation of the two options is different. The first is based on a traditional Level Set approach, in which the surface tension is distributed over a narrow band around the interface using a smoothed Delta function. In the second model, which is based on the integral form of the fluid-flow equations, the force is imposed only in those computational cells through which the interface passes. Both models have been incorporated into the Finite-Element/Finite-Volume Level Set method, previously implemented into the commercial Computational Fluid Dynamics (CFD) code CFX-4. A critical evaluation of the two models, undertaken in the context of four standard Level Set benchmark problems, shows that the first model, based on the smoothed Delta function approach, is the more general, and more robust, of the two. (author)

  7. Estimation of surface UV levels based on Meteor-3/TOMS ozone data

    Energy Technology Data Exchange (ETDEWEB)

    Borisov, Y.A. [Central Aerological Observatory, Moscow (Russian Federation); Geogdzhaev, I.V. [Moscow Inst. of Physics and Technology, Moscow (Russian Federation); Khattatov, V.U. [Central Aerological Observatory, Moscow (Russian Federation)

    1995-12-31

    The major consequence of ozone layer depletion for the environment is an increase of harmful ultraviolet (UV) radiation on the Earth surface and in the upper ocean. This implies the importance of environmental UV monitoring. Since the direct global monitoring is not currently possible, indirect estimations of surface UV levels may be used based on satellite ozone data (Madronich, S. 1992). Total Ozone Mapping Spectrometer (TOMS) on board the METEOR-3 satellite provided regular set of data for such estimates. During the time of its operation (August, 1991 - December, 1994) the instrument registered several ozone hole events over Antarctica, when ozone levels dropped by as much as 60 % from their unperturbed values. Probably even more alarming ozone depletions were observed over highly populated regions of middle latitudes of northern hemisphere. Radiative transfer modeling was used to convert METEOR-3/TOMS daily ozone values into regional and global maps of biologically active UV. Calculations demonstrate the effect on surface UV levels produced by ozone hole over Antarctica and ozone depletions over the territory of Russia (March, 1994). UV contour lines deviate from the normal appearance which is determined by growing southward solar elevation. UV contour lines are almost perpendicular to the ozone ones in the ozone depletions areas. The 30 % ozone depletion, over Siberia caused more than 30 % increase in noontime erythemal UV levels, which is equivalent to 10-15 degrees southward latitude displacement. Higher UV radiation increases were found in ozone hole over South America (October 1992) equivalent to about 20 degrees southward displacement

  8. The Effect of Three Levels of Inquiry on the Improvement of Science Concept Understanding of Elementary School Teacher Candidates

    Science.gov (United States)

    Artayasa, I. Putu; Susilo, Herawati; Lestari, Umie; Indriwati, Sri Endah

    2018-01-01

    This research aims to compare the effect of the implementation of three levels of inquiry: level 2 (structured inquiry), level 3 (guided inquiry), and level 4 (open inquiry) toward science concept understanding of elementary school teacher candidates. This is a quasi experiment research with pre-test post-test nonequivalent control group design.…

  9. Occupational exposure to beryllium in French enterprises: a survey of airborne exposure and surface levels.

    Science.gov (United States)

    Vincent, Raymond; Catani, Jacques; Créau, Yvon; Frocaut, Anne-Marie; Good, Andrée; Goutet, Pierre; Hou, Alain; Leray, Fabrice; André-Lesage, Marie-Ange; Soyez, Alain

    2009-06-01

    An assessment survey of occupational exposure to beryllium (Be) was conducted in France between late 2004 and the end of 2006. Exposure estimates were based on the analytical results of samples collected from workplace air and from work surfaces in 95 facilities belonging to 37 sectors of activity. The results of this study indicated airborne Be concentrations in excess of the occupational exposure limit value of 2 microg m(-3) recommended in France. Metallurgy and electronic component manufacturing represented the activities and occupations where workers had the highest arithmetic mean exposures to Be. Surface contamination levels were also high and frequently exceeded thresholds recommended by different bodies. These results should prompt the development of prevention programmes that include Be substitution, process control and surface decontamination, in conjunction with suitable medical surveillance.

  10. Hydraulics and drones: observations of water level, bathymetry and water surface velocity from Unmanned Aerial Vehicles

    DEFF Research Database (Denmark)

    Bandini, Filippo

    -navigable rivers and overpass obstacles (e.g. river structures). Computer vision, autopilot system and beyond visual line-of-sight (BVLOS) flights will ensure the possibility to retrieve hyper-spatial observations of water depth, without requiring the operator to access the area. Surface water speed can......The planet faces several water-related threats, including water scarcity, floods, and pollution. Satellite and airborne sensing technology is rapidly evolving to improve the observation and prediction of surface water and thus prevent natural disasters. While technological developments require....... Although UAV-borne measurements of surface water speed have already been documented in the literature, a novel approach was developed to avoid GCPs. This research is the first demonstration that orthometric water level can be measured from UAVs with a radar system and a GNSS (Global Navigation Satellite...

  11. GHRSST Level 4 MUR Global Foundation Sea Surface Temperature Analysis (v4.1) (GDS versions 1 and 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced as a retrospective dataset (four day latency) and...

  12. GHRSST Level 4 RTO Terra MODIS-AMSRE Day North America Regional Blended Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the JPL Physical...

  13. GHRSST Level 4 RTO Terra MODIS-AMSRE Night North America Regional Blended Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the JPL Physical...

  14. GHRSST Level 4 ODYSSEA North-Western Europe Regional Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at Ifremer/CERSAT...

  15. GHRSST Level 4 DMI_OI North Sea and Baltic Sea Regional Foundation Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis by the Danish...

  16. GHRSST Level 4 RTO Aqua MODIS-AMSRE Night North America Regional Blended Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the JPL Physical...

  17. GHRSST Level 4 RTO Aqua MODIS-AMSRE Day North America Regional Blended Sea Surface Temperature Analysis (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature analysis produced daily on an operational basis at the JPL Physical...

  18. GHRSST Level 4 CMC0.1deg Global Foundation Sea Surface Temperature Analysis (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature (SST) analysis produced daily on an operational basis at the Canadian...

  19. GHRSST Level 4 REMO_OI_SST_5km Regional Foundation Sea Surface Temperature Analysis (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature (SST) analysis produced daily on an operational basis by the...

  20. GHRSST Level 4 CMC0.2deg Global Foundation Sea Surface Temperature Analysis (GDS version 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) Level 4 sea surface temperature (SST) analysis produced daily on an operational basis at the Canadian...

  1. GHRSST Level 4 MW_IR_OI Global Foundation Sea Surface Temperature analysis (GDS versions 1 and 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) global Level 4 sea surface temperature analysis produced daily on a 0.81 degree grid at Remote Sensing...

  2. Sensitive determination of dopamine levels via surface-enhanced Raman scattering of Ag nanoparticle dimers.

    Science.gov (United States)

    Yu, Xiantong; He, XiaoXiao; Yang, Taiqun; Zhao, Litao; Chen, Qichen; Zhang, Sanjun; Chen, Jinquan; Xu, Jianhua

    2018-01-01

    Dopamine (DA) is an important neurotransmitter in the hypothalamus and pituitary gland, which can produce a direct influence on mammals' emotions in midbrain. Additionally, the level of DA is highly related with some important neurologic diseases such as schizophrenia, Parkinson, and Huntington's diseases, etc. In light of the important roles that DA plays in the disease modulation, it is of considerable significance to develop a sensitive and reproducible approach for monitoring DA. The objective of this study was to develop an efficient approach to quantitatively monitor the level of DA using Ag nanoparticle (NP) dimers and enhanced Raman spectroscopy. Ag NP dimers were synthesized for the sensitive detection of DA via surface-enhanced Raman scattering (SERS). Citrate was used as both the capping agent of NPs and sensing agent to DA, which is self-assembled on the surface of Ag NP dimers by reacting with the surface carboxyl group to form a stable amide bond. To improve accuracy and precision, the multiplicative effects model for surface-enhanced Raman spectroscopy was utilized to analyze the SERS assays. A low limits of detection (LOD) of 20 pM and a wide linear response range from 30 pM to 300 nM were obtained for DA quantitative detection. The SERS enhancement factor was theoretically valued at approximately 10 7 by discrete dipole approximation. DA was self-assembled on the citrate capped surface of Ag NPs dimers through the amide bond. The adsorption energy was estimated to be 256 KJ/mol using the Langmuir isotherm model. The density functional theory was used to simulate the spectral characteristics of SERS during the adsorption of DA on the surface of the Ag dimers. Furthermore, to improve the accuracy and precision of quantitative analysis of SERS assays with a multiplicative effects model for surface-enhanced Raman spectroscopy. A LOD of 20 pM DA-level was obtained, and the linear response ranged from 30 pM to 300 nM for quantitative DA detection. The

  3. The Science-Policy Link: Stakeholder Reactions to the Uncertainties of Future Sea Level Rise

    Science.gov (United States)

    Plag, H.; Bye, B.

    2011-12-01

    Policy makers and stakeholders in the coastal zone are equally challenged by the risk of an anticipated rise of coastal Local Sea Level (LSL) as a consequence of future global warming. Many low-lying and often densely populated coastal areas are under risk of increased inundation. More than 40% of the global population is living in or near the coastal zone and this fraction is steadily increasing. A rise in LSL will increase the vulnerability of coastal infrastructure and population dramatically, with potentially devastating consequences for the global economy, society, and environment. Policy makers are faced with a trade-off between imposing today the often very high costs of coastal protection and adaptation upon national economies and leaving the costs of potential major disasters to future generations. They are in need of actionable information that provides guidance for the development of coastal zones resilient to future sea level changes. Part of this actionable information comes from risk and vulnerability assessments, which require information on future LSL changes as input. In most cases, a deterministic approach has been applied based on predictions of the plausible range of future LSL trajectories as input. However, there is little consensus in the scientific community on how these trajectories should be determined, and what the boundaries of the plausible range are. Over the last few years, many publications in Science, Nature and other peer-reviewed scientific journals have revealed a broad range of possible futures and significant epistemic uncertainties and gaps concerning LSL changes. Based on the somewhat diffuse science input, policy and decision makers have made rather different choices for mitigation and adaptation in cases such as Venice, The Netherlands, New York City, and the San Francisco Bay area. Replacing the deterministic, prediction-based approach with a statistical one that fully accounts for the uncertainties and epistemic gaps

  4. Surface shift of the occupied and unoccupied 4f levels of the rare-earth metals

    DEFF Research Database (Denmark)

    Aldén, Magnus; Johansson, Börje; Skriver, Hans Lomholt

    1995-01-01

    The surface energy shifts of the occupied and unoccupied 4f levels for the lanthanide metals have been calculated from first principles by means of a Green’s-function technique within the tight-binding linear muffin-tin orbitals method. We use the concept of complete screening to identify...... the occupied and unoccupied 4f energy level shifts as the surface segregation energy of a 4fn-1 and 4fn+1 impurity atom, respectively, in a 4fn host metal. The calculations include both initial- and final-state effects and give values that are considerably lower than those measured on polycrystalline samples...... as well as those found in previous initial-state model calculations. The present theory agrees well with very recent high-resolution, single-crystal film measurements for Gd, Tb, Dy, Ho, Er, Tm, and Lu. We furthermore utilize the unique possibility offered by the lanthanide metals to clarify the roles...

  5. Technology Readiness Level Assessment Process as Applied to NASA Earth Science Missions

    Science.gov (United States)

    Leete, Stephen J.; Romero, Raul A.; Dempsey, James A.; Carey, John P.; Cline, Helmut P.; Lively, Carey F.

    2015-01-01

    Technology assessments of fourteen science instruments were conducted within NASA using the NASA Technology Readiness Level (TRL) Metric. The instruments were part of three NASA Earth Science Decadal Survey missions in pre-formulation. The Earth Systematic Missions Program (ESMP) Systems Engineering Working Group (SEWG), composed of members of three NASA Centers, provided a newly modified electronic workbook to be completed, with instructions. Each instrument development team performed an internal assessment of its technology status, prepared an overview of its instrument, and completed the workbook with the results of its assessment. A team from the ESMP SEWG met with each instrument team and provided feedback. The instrument teams then reported through the Program Scientist for their respective missions to NASA's Earth Science Division (ESD) on technology readiness, taking the SEWG input into account. The instruments were found to have a range of TRL from 4 to 7. Lessons Learned are presented; however, due to the competition-sensitive nature of the assessments, the results for specific missions are not presented. The assessments were generally successful, and produced useful results for the agency. The SEWG team identified a number of potential improvements to the process. Particular focus was on ensuring traceability to guiding NASA documents, including the NASA Systems Engineering Handbook. The TRL Workbook has been substantially modified, and the revised workbook is described.

  6. Adhesion, friction, wear, and lubrication research by modern surface science techniques.

    Science.gov (United States)

    Keller, D. V., Jr.

    1972-01-01

    The field of surface science has undergone intense revitalization with the introduction of low-energy electron diffraction, Auger electron spectroscopy, ellipsometry, and other surface analytical techniques which have been sophisticated within the last decade. These developments have permitted submono- and monolayer structure analysis as well as chemical identification and quantitative analysis. The application of a number of these techniques to the solution of problems in the fields of friction, lubrication, and wear are examined in detail for the particular case of iron; and in general to illustrate how the accumulation of pure data will contribute toward the establishment of physiochemical concepts which are required to understand the mechanisms that are operational in friction systems. In the case of iron, LEED, Auger and microcontact studies have established that hydrogen and light-saturated organic vapors do not establish interfaces which prevent iron from welding, whereas oxygen and some oxygen and sulfur compounds do reduce welding as well as the coefficient of friction. Interpretation of these data suggests a mechanism of sulfur interaction in lubricating systems.

  7. Surface and interface sciences of Li-ion batteries. -Research progress in electrode-electrolyte interface-

    Science.gov (United States)

    Minato, Taketoshi; Abe, Takeshi

    2017-12-01

    The application potential of Li-ion batteries is growing as demand increases in different fields at various stages in energy systems, in addition to their conventional role as power sources for portable devices. In particular, applications in electric vehicles and renewable energy storage are increasing for Li-ion batteries. For these applications, improvements in battery performance are necessary. The Li-ion battery produces and stores electric power from the electrochemical redox reactions between the electrode materials. The interface between the electrodes and electrolyte strongly affects the battery performance because the charge transfer causing the electrode redox reaction begins at this interface. Understanding of the surface structure, electronic structure, and chemical reactions at the electrode-electrolyte interface is necessary to improve battery performance. However, the interface is located between the electrode and electrolyte materials, hindering the experimental analysis of the interface; thus, the physical properties and chemical processes have remained poorly understood until recently. Investigations of the physical properties and chemical processes at the interface have been performed using advanced surface science techniques. In this review, current knowledge and future research prospects regarding the electrode-electrolyte interface are described for the further development of Li-ion batteries.

  8. Innovations from the “ivory tower”: Wilhelm Barthlott and the paradigm shift in surface science

    Directory of Open Access Journals (Sweden)

    Christoph Neinhuis

    2017-02-01

    Full Text Available This article is mainly about borders that have tremendous influence on our daily life, although many of them exist and act mostly unrecognized. In this article the first objective will be to address more generally the relation between university and society or industry, borders within universities, borders in thinking and the huge amount of misunderstandings and losses resulting from these obvious or hidden borders. In the second part and in more detail, the article will highlight the impact of the research conducted by Wilhelm Barthlott throughout his scientific career during which not only one border was removed, shifted or became more penetrable. Among the various fields of interest not mentioned here (e.g., systematics of Cactaceae, diversity and evolution of epiphytes, the unique natural history of isolated rocky outcrops called inselbergs, or the global distribution of biodiversity, plant surfaces and especially the tremendous diversity of minute structures on leaves, fruits, seeds and other parts of plants represent a common thread through 40 years of scientific career of Wilhelm Barthlott. Based on research that was regarded already old-fashioned in the 1970s and 1980s, systematic botany, results and knowledge were accumulated that, some 20 years later, initiated a fundamental turnover in how surfaces were recognized not only in biology, but even more evident in materials science.

  9. Surface science approach to Pt/carbon model catalysts: XPS, STM and microreactor studies

    Science.gov (United States)

    Motin, Abdul Md.; Haunold, Thomas; Bukhtiyarov, Andrey V.; Bera, Abhijit; Rameshan, Christoph; Rupprechter, Günther

    2018-05-01

    Pt nanoparticles supported on carbon are an important technological catalyst. A corresponding model catalyst was prepared by physical vapor deposition (PVD) of Pt on sputtered HOPG (highly oriented pyrolytic graphite). The carbon substrate before and after sputtering as well as the Pt/HOPG system before and after Pt deposition and annealing were examined by XPS and STM. This yielded information on the surface density of defects, which serve as nucleation centres for Pt, and on the size distribution (mean size/height) of the Pt nanoparticles. Two different model catalysts were prepared with mean sizes of 2.0 and 3.6 nm, both turned out to be stable upon UHV-annealing to 300 °C. After transfer into a UHV-compatible flow microreactor and subsequent cleaning in UHV and under mbar pressure, the catalytic activity of the Pt/HOPG model system for ethylene hydrogenation was examined under atmospheric pressure flow conditions. This enabled to determine temperature-dependent conversion rates, turnover frequencies (TOFs) and activation energies. The catalytic results obtained are in line with the characteristics of technological Pt/C, demonstrating the validity of the current surface science based model catalyst approach.

  10. Site characterization field manual for near surface geologic disposal of low-level radioactive waste

    International Nuclear Information System (INIS)

    McCray, J.G.; Nowatzki, E.A.

    1985-01-01

    This field manual has been developed to aid states and regions to do a detailed characterization of a proposed near-surface low-level waste disposal site. The field manual is directed at planners, staff personnel and experts in one discipline to acquaint them with the requirements of other disciplines involved in site characterization. While it can provide a good review, it is not designed to tell experts how to do their job within their own discipline

  11. Polarization-induced renormalization of molecular levels at metallic and semiconducting surfaces

    DEFF Research Database (Denmark)

    García Lastra, Juan Maria; Rostgaard, Carsten; Rubio, A.

    2009-01-01

    On the basis of first-principles G0W0 calculations we systematically study how the electronic levels of a benzene molecule are renormalized by substrate polarization when physisorbed on different metallic and semiconducting surfaces. The polarization-induced reduction in the energy gap between oc...... find that error cancellations lead to remarkably good agreement between the G0W0 and Kohn-Sham energies for the occupied orbitals of the adsorbed molecule....

  12. Radiation levels in the poll surface of IEA-R1 reactor

    International Nuclear Information System (INIS)

    Pasqualetto, H.

    1978-01-01

    A theoretical model for the calculation of the radioactivity level in the pool surface of the research reactor IEA-RI (INSTITUTO DE ENERGIA ATOMICA, BRAZIL) is developed. The radioactivity is caused by radionuclides (Mainly 24 Na and 27 Mg) produced by nuclear reactions of neutrons with: a) oxygen of the water b); gaseous elements dissolved in water (Ar,N); c) structural materials of the fuel can. Considerations about expected radiation level after eventual increase of reactor power from 2 MW to 10 MW are also presented [pt

  13. Iterative algorithm for reconstructing rotationally asymmetric surface deviation with pixel-level spatial resolution

    Science.gov (United States)

    Quan, Haiyang; Wu, Fan; Hou, Xi

    2015-10-01

    New method for reconstructing rotationally asymmetric surface deviation with pixel-level spatial resolution is proposed. It is based on basic iterative scheme and accelerates the Gauss-Seidel method by introducing an acceleration parameter. This modified Successive Over-relaxation (SOR) is effective for solving the rotationally asymmetric components with pixel-level spatial resolution, without the usage of a fitting procedure. Compared to the Jacobi and Gauss-Seidel method, the modified SOR method with an optimal relaxation factor converges much faster and saves more computational costs and memory space without reducing accuracy. It has been proved by real experimental results.

  14. The Teaching Processes of Prospective Science Teachers with Different Levels of Science-Teaching Self-Efficacy Belief

    Science.gov (United States)

    Saka, Mehpare; Bayram, Hale; Kabapinar, Filiz

    2016-01-01

    The concept of self-efficacy, which is an important variable in the teaching process, and how it reflects on teaching have recently been the focus of attention. Therefore, this study deals with the relationship between the science-teaching self-efficacy beliefs of prospective science teachers and their teaching practices. It was conducted with…

  15. Determination of Pre-Service Science Teachers' Level of Awareness of Environmental Ethics in Relation to Different Variables

    Science.gov (United States)

    Keles, Özgül; Özer, Nilgün

    2016-01-01

    The purpose of the current study is to determine the pre-service science teachers' awareness levels of environmental ethics in relation to different variables. The sampling of the present study is comprised of 1,023 third and fourth year pre-service science teachers selected from 12 different universities in the spring term of 2013-2014 academic…

  16. A Balancing Act in the Third Space: Graduate-Level Earth Science in an Urban Teacher-Residency Program

    Science.gov (United States)

    Zirakparvar, N. Alex

    2015-01-01

    This article describes a museum-based urban teacher-residency (UTR) program's approach to building subject-specific content knowledge and research experience in Earth Science teacher candidates. In the museum-based program, graduate-level science courses and research experiences are designed and implemented specifically for the UTR by active Earth…

  17. Strategic Alliance to Advanced Technological Education through Enhanced Mathematics, Science, Technology, and English Education at the Secondary Level

    Science.gov (United States)

    Scarborough, Jule Dee

    2004-01-01

    This document (book) reports on the Strategic Alliance to Advance Technological Education through Enhanced Mathematics, Science, Technology, and English Education at the Secondary Level, funded by National Science Foundation. It was a collaborative partnership involving the Rockford Public Schools, Rock Valley College, and Northern Illinois…

  18. Regression Levels of Selected Affective Factors on Science Achievement: A Structural Equation Model with TIMSS 2011 Data

    Science.gov (United States)

    Akilli, Mustafa

    2015-01-01

    The aim of this study is to demonstrate the science success regression levels of chosen emotional features of 8th grade students using Structural Equation Model. The study was conducted by the analysis of students' questionnaires and science success in TIMSS 2011 data using SEM. Initially, the factors that are thought to have an effect on science…

  19. Investigation of Entrepreneurship Trends and General Competency Levels of University Students Studying at Faculty of Sports Sciences

    Science.gov (United States)

    Karabulut, Ebru Olcay; Dogan, Pinar Karacan

    2018-01-01

    The aim of this study is to determine the general competency beliefs and entrepreneurial levels of undergraduate students studying at faculty of sports sciences by different demographic variables. The sample group consists of total 1230 students, 541 women and 689 men, who have been educated in the sport sciences of five different universities and…

  20. Wetland Ecohydrology: stochastic description of water level fluctuations across the soil surface

    Science.gov (United States)

    Tamea, S.; Muneepeerakul, R.; Laio, F.; Ridolfi, L.; Rodriguez-Iturbe, I.

    2009-12-01

    Wetlands provide a suite of social and ecological critical functions such as being habitats of disease-carrying vectors, providing buffer zones against hurricanes, controlling sediment transport, filtering nutrients and contaminants, and a repository of great biological diversity. More recently, wetlands have also been recognized as crucial for carbon storage in the context of global climate change. Despite such importance, quantitative approaches to many aspects of wetlands are far from adequate. Therefore, improving our quantitative understanding of wetlands is necessary to our ability to maintain, manage, and restore these invaluable environments. In wetlands, hydrologic factors and ecosystem processes interplay and generate unique characteristics and a delicate balance between biotic and abiotic elements. The main hydrologic driver of wetland ecosystems is the position of the water level that, being above or below ground, determines the submergence or exposure of soil. When the water level is above the soil surface, soil saturation and lack of oxygen causes hypoxia, anaerobic functioning of microorganisms and anoxic stress in plants, that might lead to the death of non-adapted organisms. When the water level lies below the soil surface, the ecosystem becomes groundwater-dependent, and pedological and physiological aspects play their role in the soil water balance. We propose here a quantitative description of wetland ecohydrology, through a stochastic process-based water balance, driven by a marked compound Poisson noise representing rainfall events. The model includes processes such as rainfall infiltration, evapotranspiration, capillary rise, and the contribution of external water bodies, which are quantified in a simple yet realistic way. The semi-analytical steady-state probability distributions of water level spanning across the soil surface are validated with data from the Everglades (Florida, USA). The model and its results allow for a quantitative

  1. Participatory System Science: Multi-Level Comprehension Through a Game-like Process

    Science.gov (United States)

    Fatland, D. R.; Kuntz, L.

    2012-12-01

    Participatory System Science: Multi-Level Comprehension Through a Game-like Process We built a time-series game that permits the player to make water management decisions concerning the Skagit River (north-central Washington state) every five years for 60 years. This work was inspired by the integrative efforts of the Skagit Climate Science Consortium and the Climate Impacts Group at the University of Washington. Our principle guiding concepts have been - Construct a reasonable system description with -- wherever possible -- Events / Consequences rendered both visually and in terms of financial impact. - Base the system description on peer reviewed publications - Emphasize both connection and absence of connection between player Actions and subsequent Consequences in the catchment basin. Player choices center around dam flow levels and steps to mitigate negative impacts of sediment transport into the lower (populated) reaches of the Skagit River and into Puget Sound (levees, new dams, estuary restoration, etcetera). With this work we hope to explore scientific results in public awareness by engaging the game Player as a problem solver.

  2. Measuring Student Improvement in Lower- and Upper-Level University Climate Science Courses

    Science.gov (United States)

    Harris, S. E.; Taylor, S. V.; Schoonmaker, J. E.; Lane, E.; Francois, R. H.; Austin, P.

    2011-12-01

    What do university students know about climate? What do they learn in a climate course? On the second-to-last day of a course about global climate change, only 48% of our upper-level science students correctly answered a multiple-choice question about the greenhouse effect. The good news: improvement. Only 16% had answered correctly on the first day of class. The bad news: the learning opportunities we've provided appear to have missed more than half the class on a fundamental climate concept. To evaluate the effectiveness of instruction on student learning about climate, we have developed a prototype assessment tool, designed to be deployed as a low-stakes pre-post test. The items included were validated through student interviews to ensure that students interpret the wording and answer choices in the way we intend. This type of validated assessment, administered both at the beginning and end of term, with matched individuals, provides insight regarding the baseline knowledge with which our students enter a course, and the impact of that course on their learning. We administered test items to students in (1) an upper-level climate course for science majors and (2) a lower-level climate course open to all students. Some items were given to both groups, others to only one of the groups. Both courses use evidence-based pedagogy with active student engagement (clickers, small group activities, regular pre-class preparation). Our results with upper-level students show strong gains in student thinking (>70% of students who missed a question on the pre-test answered correctly on the post-test) about stock-and-flow (box model) problems, annual cycles in the Keeling curve, ice-albedo feedbacks, and isotopic fractionation. On different questions, lower-level students showed strong gains regarding albedo and blackbody emission spectra. Both groups show similar baseline knowledge and lower-than-expected gains on greenhouse effect fundamentals, and zero gain regarding the

  3. Hierarchical Effects of School-, Classroom-, and Student-Level Factors on the Science Performance of Eighth-Grade Taiwanese Students

    Science.gov (United States)

    Tsai, Liang-Ting; Yang, Chih-Chien

    2015-05-01

    This study was conducted to understand the effect of student-, classroom-, and school-level factors on the science performance of 8th-grade Taiwanese students in the Trends in International Mathematics and Science Study (TIMSS) 2011 by using multilevel analysis. A total of 5,042 students from 153 classrooms of 150 schools participated in the TIMSS 2011 study, in which they were required to complete questionnaires. A 3-level multilevel analysis was used to assess the influence of factors at 3 levels on the science performance of 8th-grade Taiwanese students. The results showed that the provision of education resources at home, teachers' level of education, and school climate were the strongest predictor of science performance at the student, classroom, and school level, respectively. It was concluded that the science performance of 8th-grade Taiwanese students is driven largely by individual factors. Classroom-level factors accounted for a smaller proportion of the total variance in science performance than did school-level factors.

  4. Development, Characterization, and Optimization of Protein Level in Date Bars Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Muhammad Nadeem

    2012-01-01

    Full Text Available This project was designed to produce a nourishing date bar with commercial value especially for school going children to meet their body development requirements. Protein level of date bars was optimized using response surface methodology (RSM. Economical and underutilized sources, that is, whey protein concentrate and vetch protein isolates, were explored for protein supplementation. Fourteen date bar treatments were produced using a central composite design (CCD with 2 variables and 3 levels for each variable. Date bars were then analyzed for nutritional profile. Proximate composition revealed that addition of whey protein concentrate and vetch protein isolates improved the nutritional profile of date bars. Protein level, texture, and taste were considerably improved by incorporating 6.05% whey protein concentrate and 4.35% vetch protein isolates in date bar without affecting any sensory characteristics during storage. Response surface methodology was observed as an economical and effective tool to optimize the ingredient level and to discriminate the interactive effects of independent variables.

  5. Project-Based Learning as a Vehicle for Teaching Science at the University Level

    Science.gov (United States)

    Courtney, A. R.; Wade, P.

    2012-12-01

    In a typical science course learning is teacher directed. Students are presented with knowledge and concepts via textbooks and lecture and then given the opportunity to apply them. Project-based learning (PBL) creates a context and reason to learn information and concepts. In PBL, learning is student directed and teacher facilitated. Students take ownership of their learning by finding, evaluating and synthesizing information from a variety of resources and via interaction between each other. In PBL, the project is central rather than peripheral to the curriculum. It is not just an activity that provides examples, additional practice or applications of the course content, but rather, the vehicle through which major concepts are discovered. The PBL process requires students to do revision and reflection encouraging them to think about what and how they are learning. PBL projects also allow students to develop important life-work skills such as collaboration, communication and critical thinking within the discipline. We have employed PBL in both Liberal Arts courses for non-science majors and upper division courses for science students. Three examples will be discussed. The first will be the production of video documentaries in a non-science major course; the second, a student generated electronic textbook in a 300-level energy course for science students; and lastly, a student designed analysis project in a chemistry major capstone laboratory course. The product in each of these examples was used to deliver knowledge to others in the class as well as members of the public providing motivation for students to do high-quality work. In our examples, student documentaries are publicly screened as part of a university-wide Academic Excellence Showcase; the student generated electronic textbook is available for public use on the internet; and the results of the student designed analysis were communicated to the real-world clients via letters and reports. We will discuss

  6. Surface-type repository for low and intermediate level radioactive waste in the Republic of Croatia

    International Nuclear Information System (INIS)

    Kucar-Dragicevic, S.; Zarkovic, V.; Subasic, D.

    1995-01-01

    The low-level intermediate-level (LL/IL) radioactive waste repository siting and construction project is one of the activities related to establishing the rad waste management system in the Republic of Croatia. The repository project design is one in an array of project activities which also include the site selection procedure and public attitude issues. The prepared design documentation gives technical, safety and financial background relevant for making a final decision on the waste disposal type, and it includes the technological, mechanical, civil and financial documentation on the preliminary/basic design level. During the last few years, the preliminary design has been prepared and safety assessment conducted for the tunnel-type LL/IL rad waste repository. As the surface-type repository is one of alternatives for final disposal the design documentation for that repository type was prepared during 1994. (author)

  7. Evaluation of bubbler/diaphragm techniques to measure surface level in the waste storage tanks

    International Nuclear Information System (INIS)

    Peters, T.J.; Hickman, B.J.; Colson, J.B.

    1993-10-01

    This report describes the results of tests conducted at the Pacific Northwest Laboratory (PNL) to determine if a bubbler technique can be used to determine the surface level in the waste tanks. Two techniques were evaluated. The first technique is a standard bubbler system in which a tube is placed below the surface of the liquid to be measured and air pressure inside a tube is increased until bubbles begin to become emitted from the tube. The air pressure then is a function of the pressure at the bottom of the tube. The second technique involves a system similar to the standard bubbler technique, but instead of bubbles being released into the material to be gauged, air pressure is increased against a diaphragm until enough pressure is applied to overcome the pressure of the liquid at the given depth, at which time the air then flows in a return loop back to a vent. The advantage of the diaphragm system is that it is a sealed system; thus no air is released into the waste tank materials, and it is not possible for the waste tank materials to get into the air flow. Based on the results of the tests conducted in this program, it appears that the bubbler and diaphragm systems that were tested could not be used for accurate measurements of the level in the waste tanks. Both exhibited deposits of simulated waste tank material at the end of the devices which affected the ability of the gauge to accurately determine changes in the surface level even though the measured value of the level was inaccurate. Further investigations into the cause of this inaccuracy may be warranted. Alternate diaphragm materials may improve the performance of this gauge

  8. Surface shift of the occupied and unoccupied 4f levels of the rare-earth metals

    Science.gov (United States)

    Aldén, M.; Johansson, B.; Skriver, H. L.

    1995-02-01

    The surface energy shifts of the occupied and unoccupied 4f levels for the lanthanide metals have been calculated from first principles by means of a Green's-function technique within the tight-binding linear muffin-tin orbitals method. We use the concept of complete screening to identify the occupied and unoccupied 4f energy level shifts as the surface segregation energy of a 4fn-1 and 4fn+1 impurity atom, respectively, in a 4fn host metal. The calculations include both initial- and final-state effects and give values that are considerably lower than those measured on polycrystalline samples as well as those found in previous initial-state model calculations. The present theory agrees well with very recent high-resolution, single-crystal film measurements for Gd, Tb, Dy, Ho, Er, Tm, and Lu. We furthermore utilize the unique possibility offered by the lanthanide metals to clarify the roles played by the initial and the different final states of the core-excitation process, permitted by the fact that the so-called initial-state effect is identical upon 4f removal and 4f addition. Surface energy and work function calculations are also reported.

  9. Exceptionally crystalline and conducting acid doped polyaniline films by level surface assisted solution casting approach

    Energy Technology Data Exchange (ETDEWEB)

    Puthirath, Anand B.; Varma, Sreekanth J.; Jayalekshmi, S., E-mail: jayalekshmi@cusat.ac.in [Division for Research in Advanced Materials, Department of Physics, Cochin University of Science and Technology, Cochin, Kerala 682022 (India); Methattel Raman, Shijeesh [Nanophotonic and Optoelectronic Devices Laboratory, Department of Physics, Cochin University of Science and Technology, Cochin, Kerala 682022 (India)

    2016-04-18

    Emeraldine salt form of polyaniline (PANI) was synthesized by chemical oxidative polymerisation method using ammonium persulfate as oxidant. Resultant emeraldine salt form of PANI was dedoped using ammonia solution and then re-doped with camphor sulphonic acid (CSA), naphthaline sulphonic acid (NSA), hydrochloric acid (HCl), and m-cresol. Thin films of these doped PANI samples were deposited on glass substrates using solution casting method with m-cresol as solvent. A level surface was employed to get homogeneous thin films of uniform thickness. Detailed X-ray diffraction studies have shown that the films are exceptionally crystalline. The crystalline peaks observed in the XRD spectra can be indexed to simple monoclinic structure. FTIR and Raman spectroscopy studies provide convincing explanation for the exceptional crystallinity observed in these polymer films. FESEM and AFM images give better details of surface morphology of doped PANI films. The DC electrical conductivity of the samples was measured using four point probe technique. It is seen that the samples also exhibit quite high DC electrical conductivity, about 287 S/cm for CSA doped PANI, 67 S/cm for NSA doped PANI 65 S/cm for HCl doped PANI, and just below 1 S/cm for m-cresol doped PANI. Effect of using the level surface for solution casting is studied and correlated with the observed crystallinity.

  10. Reduction of Fermi level pinning and recombination at polycrystalline CdTe surfaces by laser irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Simonds, Brian J. [Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah 84112 (United States); Kheraj, Vipul [Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah 84112 (United States); Department of Applied Physics, S. V. National Institute of Technology, Surat 395 007 (India); Palekis, Vasilios; Ferekides, Christos [Electrical Engineering, University of South Florida, Tampa, Florida 33620 (United States); Scarpulla, Michael A., E-mail: scarpulla@eng.utah.edu [Electrical and Computer Engineering, University of Utah, Salt Lake City, Utah 84112 (United States); Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112 (United States)

    2015-06-14

    Laser processing of polycrystalline CdTe is a promising approach that could potentially increase module manufacturing throughput while reducing capital expenditure costs. For these benefits to be realized, the basic effects of laser irradiation on CdTe must be ascertained. In this study, we utilize surface photovoltage spectroscopy (SPS) to investigate the changes to the electronic properties of the surface of polycrystalline CdTe solar cell stacks induced by continuous-wave laser annealing. The experimental data explained within a model consisting of two space charge regions, one at the CdTe/air interface and one at the CdTe/CdS junction, are used to interpret our SPS results. The frequency dependence and phase spectra of the SPS signal are also discussed. To support the SPS findings, low-temperature spectrally-resolved photoluminescence and time-resolved photoluminescence were also measured. The data show that a modest laser treatment of 250 W/cm{sup 2} with a dwell time of 20 s is sufficient to reduce the effects of Fermi level pinning at the surface due to surface defects.

  11. Should applicants to Nottingham University Medical School study a non-science A-level?: a cohort study

    OpenAIRE

    Yates, Janet; Smith, Jennifer; James, David; Ferguson, Eamonn

    2009-01-01

    Abstract Background It has been suggested that studying non-science subjects at A-level should be compulsory for medical students. Our admissions criteria specify only Biology, Chemistry and one or more additional subjects. This study aimed to determine whether studying a non-science subject for A-level is an independent predictor of achievement on the undergraduate medical course. Methods The subjects of this retrospective cohort study were 164 students from one entry-year group (October 200...

  12. Integrating Hands-On Undergraduate Research in an Applied Spatial Science Senior Level Capstone Course

    Science.gov (United States)

    Kulhavy, David L.; Unger, Daniel R.; Hung, I-Kuai; Douglass, David

    2015-01-01

    A senior within a spatial science Ecological Planning capstone course designed an undergraduate research project to increase his spatial science expertise and to assess the hands-on instruction methodology employed within the Bachelor of Science in Spatial Science program at Stephen F Austin State University. The height of 30 building features…

  13. Relict benthic foraminifera in surface sediments off central east coast of India as indicator of sea level changes

    Digital Repository Service at National Institute of Oceanography (India)

    Rana, S.S.; Nigam, R.; Panchang, R.

    surface samples is characteristic of coral reef environment and has been inferred as evidence for past low sea levels. Based on extrapolation of previously published radiocarbon dates from the region, we propose a pliable sea level curve for the period...

  14. Examination of the Life Satisfactions Levels of Students Receiving Education in Sports Sciences

    Directory of Open Access Journals (Sweden)

    Abdullah Bora ÖZKARA

    2015-07-01

    Full Text Available The aim of this study is to examine of life satisfaction levels of students receiving education in sports science according to some variabl es. To this aim, individual info form and Turkish form of life satisfaction questionnaire , developed by Diener, Emmos, Larsen and Griffin (1985 and adapted to Turkish by Kokler (1991 4, were administered ,as a online, to 25 4 students from Ağrı İbrahim Çeçen University, Afyon Kocatepe University, Dumlupınar University and Karadeniz Technical University with voluntary participation. Depending on the data on gender, smoking, universities,alchool using and family income were app lied Kolmogorov - Smirnov normality test. The tests results indicated that the data are not normally distributed. Depending on the data; for gender, smoking, alchool using Mann - Whitney U test, for universities and family income Kruskal - Wallis tests were use d at the level of α=0.05 significance.The result showed that there was no significant differences on genders ((Z 0.05 ; - 1,616; P>0.05, smoking (Z 0.05 ; - 1,556; P>0.05 and universities (X 2 (3; 0,.370; P>0.05 according to life satisfaction levels. On the o ther hand; alchool using (Z 0.05 ; - 2,008; P<0.05 and family income (X 2 (3; 10,257; P<0.05 scores were found significant depending on life satisfaction levels .

  15. Past and future sea-level change from the surface mass balance of glaciers

    Directory of Open Access Journals (Sweden)

    B. Marzeion

    2012-11-01

    Full Text Available We present estimates of sea-level change caused by the global surface mass balance of glaciers, based on the reconstruction and projection of the surface mass balance of all the individual glaciers of the world, excluding the ice sheets in Greenland and Antarctica. The model is validated using a leave-one-glacier-out cross-validation scheme against 3997 observed surface mass balances of 255 glaciers, and against 756 geodetically observed, temporally integrated volume and surface area changes of 341 glaciers. When forced with observed monthly precipitation and temperature data, the glaciers of the world are reconstructed to have lost mass corresponding to 114 ± 5 mm sea-level equivalent (SLE between 1902 and 2009. Using projected temperature and precipitation anomalies from 15 coupled general circulation models from the Coupled Model Intercomparison Project phase 5 (CMIP5 ensemble, they are projected to lose an additional 148 ± 35 mm SLE (scenario RCP26, 166 ± 42 mm SLE (scenario RCP45, 175 ± 40 mm SLE (scenario RCP60, or 217 ± 47 mm SLE (scenario RCP85 during the 21st century. Based on the extended RCP scenarios, glaciers are projected to approach a new equilibrium towards the end of the 23rd century, after having lost either 248 ± 66 mm SLE (scenario RCP26, 313 ± 50 mm SLE (scenario RCP45, or 424 ± 46 mm SLE (scenario RCP85. Up until approximately 2100, ensemble uncertainty within each scenario is the biggest source of uncertainty for the future glacier mass loss; after that, the difference between the scenarios takes over as the biggest source of uncertainty. Ice mass loss rates are projected to peak 2040 ∼ 2050 (RCP26, 2050 ∼ 2060 (RCP45, 2070 ∼ 2090 (RCP60, or 2070 ∼ 2100 (RCP85.

  16. Two-Level Micro-to-Nanoscale Hierarchical TiO2 Nanolayers on Titanium Surface

    Directory of Open Access Journals (Sweden)

    Elena G. Zemtsova

    2016-12-01

    Full Text Available Joint replacement is being actively developed within modern orthopedics. One novel material providing fast implantation is bioactive coatings. The synthesis of targeted nanocoatings on metallic nanotitanium surface is reported in this paper. TiO2-based micro- and nanocoatings were produced by sol-gel synthesis using dip-coating technology with subsequent fast (shock drying in hot plate mode at 400 °C. As a result of shock drying, the two-level hierarchical TiO2 nanolayer on the nanotitanium was obtained. This two-level hierarchy includes nanorelief of porous xerogel and microrelief of the micron-sized “defect” network (a crack network. The thickness of TiO2 nanolayers was controlled by repeating dip-coating process the necessary number of times after the first layer deposition. The state of the MS3T3-E1 osteoblast cell line (young cells that form bone tissue on the two-level hierarchical surface has been studied. Particularly, adhesion character, adhesion time and morphology have been studied. The reported results may serve the starting point for the development of novel bioactive coatings for bone and teeth implants.

  17. Surface Water Connectivity, Flow Pathways and Water Level Fluctuation in a Cold Region Deltaic Ecosystem

    Science.gov (United States)

    Peters, D. L.; Niemann, O.; Skelly, R.; Monk, W. A.; Baird, D. J.

    2017-12-01

    The Peace-Athabasca Delta (PAD) is a 6000 km2 deltaic floodplain ecosystem of international importance (Wood Buffalo National Park, Ramsar Convention, UNESCO World Heritage, and SWOT satellite water level calibration/validation site). The low-relief floodplain formed at the confluence of the Peace, Athabasca and Birch rivers with Lake Athabasca. More than 1000 wetland and lake basins have varying degrees of connectivity to the main flow system. Hydroperiod and water storage is influenced by ice-jam and open-water inundations and prevailing semi-arid climate that control water drawdown. Prior studies have identified pathways of river-to-wetland floodwater connection and historical water level fluctuation/trends as a key knowledge gaps, limiting our knowledge of deltaic ecosystem status and potential hydroecological responses to climate change and upstream water alterations to flow contributions. To address this knowledge gap, surface elevation mapping of the PAD has been conducted since 2012 using aerial remote sensing Light Detection and Ranging (LiDAR), plus thousands of ground based surface and bathymetric survey points tied to Global Positioning System (GPS) were obtained. The elevation information was used to develop a high resolution digital terrain model to simulate and investigate surface water connectivity. Importantly, the surveyed areas contain a set of wetland monitoring sites where ground-based surface water connectivity, water level/depth, water quality, and aquatic ecology (eg, vegetation, macroinvertebrate and muskrat) have been examined. The goal of this presentation is to present an assessment of: i) surface water fluctuation and connectivity for PAD wetland sites; ii) 40+ year inter-annual hydroperiod reconstruction for a perched basin using a combination of field measurements, remote sensing estimates, and historical documents; and iii) outline an approach to integrate newly available hydro-bio-geophysical information into a novel, multi

  18. On-Orbit Planetary Science Laboratories for Simulating Surface Conditions of Planets and Small Bodies

    Science.gov (United States)

    Thangavelautham, J.; Asphaug, E.; Schwartz, S.

    2017-02-01

    Our work has identified the use of on-orbit centrifuge science laboratories as a key enabler towards low-cost, fast-track physical simulation of off-world environments for future planetary science missions.

  19. Water Adsorption on Clean and Defective Anatase TiO2 (001) Nanotube Surfaces: A Surface Science Approach.

    Science.gov (United States)

    Kenmoe, Stephane; Lisovski, Oleg; Piskunov, Sergei; Bocharov, Dmitry; Zhukovskii, Yuri F; Spohr, Eckhard

    2018-04-11

    We use ab initio molecular dynamics simulations to study the adsorption of thin water films with 1 and 2 ML coverage on anatase TiO 2 (001) nanotubes. The nanotubes are modeled as 2D slabs, which consist of partially constrained and partially relaxed structural motifs from nanotubes. The effect of anion doping on the adsorption is investigated by substituting O atoms with N and S impurities on the nanotube slab surface. Due to strain-induced curvature effects, water adsorbs molecularly on defect-free surfaces via weak bonds on Ti sites and H bonds to surface oxygens. While the introduction of an S atom weakens the interaction of the surface with water, which adsorbs molecularly, the presence of an N impurity renders the surface more reactive to water, with a proton transfer from the water film and the formation of an NH group at the N site. At 2 ML coverage, a further surface-assisted proton transfer takes place in the water film, resulting in the formation of an OH - group and an NH 2 + cationic site on the surface.

  20. Two sides of the coin. Part 2. Colloid and surface science meets real biointerfaces.

    Science.gov (United States)

    Ninham, Barry W; Larsson, Kåre; Lo Nostro, Pierandrea

    2017-11-01

    Part 1 revisited developments in lipid and surfactant self assembly over the past 40 years [1]. New concepts emerged. Here we explore how these developments can be used to make sense of and bring order to a range of complex biological phenomena. Together with Part 1, this contribution is a fundamental revision of intuition at the boundaries of Colloid Science and Biological interfaces from a perspective of nearly 50 years. We offer new insights on a unified treatment of self assembly of lipids, surfactants and proteins in the light of developments presented in Part 1. These were in the enabling disciplines in molecular forces, hydration, oil and electrolyte specificity; and in the role of non Euclidean geometries-across the whole gammut of physical, colloid and surface chemistry, biophysics and membrane biology and medicine. It is where the early founders of the cell theory of biology and the physiologists expected advances to occur as D'Arcy Thompson predicted us 100 years ago. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. The New Horizons Bistatic Radio Science Experiment to Measure Pluto's Surface Properties

    Science.gov (United States)

    Linscott, I.; Hinson, D. P.; Tyler, G. L.; Vincent, M.

    2014-12-01

    The New Horizons (NH) payload includes a Radio Science Experiment (REX) for principally occultation and radiometric measurement of Pluto and Charon during the flyby in July 2015. The REX subsystem is contained, together with the NH X-Band radio, in the Integrated Electronics Module (IEM) in the New Horizons spacecraft. REX samples and records in two polarizations both total RF power in a 4.5 MHz bandwidth, and radio signal waveforms in a narrow, 1.25 kHz band. During the encounter, and at closest approach to Pluto, the spacecraft's high gain antenna (HGA) will scan Pluto's equatorial latitudes, intercepting the specular zone, a region near Pluto's limb that geometrically favors reflection from the earth's direction. At the same time, a powerful 80 kW uplink beacon will have been transmitted from earth by the DSN to arrive at Pluto during spacecraft closest approach. Reflection from the specular zone is expected to be sufficiently strong to observe the bistatic uplink in the REX narrowband record. Measurements in both polarizations will then be combined to yield surface reflectivity, roughness and limits on the dielectric constant in the specular zone.

  2. Actionable Science for Sea Level Rise and Coastal Flooding to Help Avoid Maladaptation

    Science.gov (United States)

    Buchanan, M. K.

    2017-12-01

    Rising sea levels increase the frequency of flooding at all levels, from nuisance to extreme, along coastlines across the world. Although recent flooding has increased the saliency of sea level rise (SLR) and the risks it presents to governments and communities, the effect of SLR on coastal hazards is complex and filled with uncertainty that is often uncomfortable for decision-makers. Although it is certain that SLR is occurring and will continue, its rate remains ambiguous. Because extreme flooding is by definition rare, there is also uncertainty in the effect of natural variability on flood frequency. These uncertainties pose methodological obstacles for integrating SLR into flood hazard projections and risk management. A major challenge is how to distill this complexity into information geared towards public sectors to help inform adaptation decision-making. Because policy windows are limited, budgets are tight, and decisions may have long-term consequences, it is especially important that this information accounts for uncertainty to help avoid damage and maladaptation. The U.S. Global Research Program, and others, describe this type of science—data and tools that help decision-makers plan for climate change impacts—as actionable [1]. We produce actionable science to support decision-making for adaptation to coastal impacts, despite uncertainty in projections of SLR and flood frequency. We found that SLR will boost the occurrence of minor rather than severe flooding in some regions of the U.S., while in other regions the reverse is true. For many cities, the current ten-year flood level will become a regular occurrence as the century progresses and by 2100 will occur every few days for some cities. This creates a mismatch with current planning in some cases. For example, a costly storm surge barrier may be built to protect parts of New York City from extreme flood levels but these are not often used because they are expensive to operate and obstructive to

  3. Developing models to predict 8th grade students' achievement levels on timss science based on opportunity-to-learn variables

    Science.gov (United States)

    Whitford, Melinda M.

    Science educational reforms have placed major emphasis on improving science classroom instruction and it is therefore vital to study opportunity-to-learn (OTL) variables related to student science learning experiences and teacher teaching practices. This study will identify relationships between OTL and student science achievement and will identify OTL predictors of students' attainment at various distinct achievement levels (low/intermediate/high/advanced). Specifically, the study (a) address limitations of previous studies by examining a large number of independent and control variables that may impact students' science achievement and (b) it will test hypotheses of structural relations to how the identified predictors and mediating factors impact on student achievement levels. The study will follow a multi-stage and integrated bottom-up and top-down approach to identify predictors of students' achievement levels on standardized tests using TIMSS 2011 dataset. Data mining or pattern recognition, a bottom-up approach will identify the most prevalent association patterns between different student achievement levels and variables related to student science learning experiences, teacher teaching practices and home and school environments. The second stage is a top-down approach, testing structural equation models of relations between the significant predictors and students' achievement levels according.

  4. A Model for Teaching a Climate Change Elective Science Course at the Community College Level

    Science.gov (United States)

    Mandia, S. A.

    2012-12-01

    The impact of global climate change is far-reaching, both for humanity and for the environment. It is essential that our students be provided a strong scientific background for the role of natural and human caused climate change so that they are better prepared to become involved in the discussion. Here the author reveals a successful model designed for use with a diverse student body at the community college level. Teaching strategies beyond the traditional lecture and exam style include: web-based resources such as static websites along with dynamic blogging tools, post-lecture cooperative learning review sessions, weekly current event research projects, use of rubrics to assist students in their own project evaluation before submission, and a research paper utilizing the Skeptical Science website to examine the validity of the most common climate change myths.

  5. Learner Inclinations to Study Computer Science or Information Systems at Tertiary Level

    Directory of Open Access Journals (Sweden)

    C Jacobs

    2010-07-01

    Full Text Available After the so‐called “dot‐com crash” of the Internet in the early 2000s, tertiary level student enrolments in IT‐related subjects began to experience a significant decline both in international countries and South Africa. The paper replicates research done in the Western Cape, South Africa, by Seymour et al. (2005 [20], in which grade 12 learner inclinations to study Computer Science (CS and Information Systems (IS at tertiary level were analysed and underlying factors affecting their interest in the subjects were determined. The study analyses the “misguided” perceptions that learners and students have of these subjects; the implications of the decline in enrolments on students, educational sectors and industry; and determines a set of underlying factors that influence learners in their attitudes toward further degrees in IT, starting from the secondary level of education. The research compares South African Eastern Cape learner perceptions with those from the Western Cape study and establishes three to four years later, that the reasons behind the decline in IT enrolments are still influenced by an underlying demographic and digital divide.

  6. Learner Inclinations to Study Computer Science or Information Systems at Tertiary Level

    Directory of Open Access Journals (Sweden)

    C Jacobs

    2010-08-01

    Full Text Available After the so-called “dot-com crash” of the Internet in the early 2000s, tertiary level student enrolments in IT-related subjects began to experience a significant decline both in international countries and South Africa. The paper replicates research done in the Western Cape, South Africa, by Seymour et al. (2005 [20], in which grade 12 learner inclinations to study Computer Science (CS and Information Systems (IS at tertiary level were analysed and underlying factors affecting their interest in the subjects were determined. The study analyses the “misguided” perceptions that learners and students have of these subjects; the implications of the decline in enrolments on students, educational sectors and industry; and determines a set of underlying factors that influence learners in their attitudes toward further degrees in IT, starting from the secondary level of education. The research compares South African Eastern Cape learner perceptions with those from the Western Cape study and establishes three to four years later, that the reasons behind the decline in IT enrolments are still influenced by an underlying demographic and digital divide.

  7. Survey of Anxiety Levels and Its Relation to Students Demographic of Alborz University of Medical Sciences

    Directory of Open Access Journals (Sweden)

    R. Norouzinia

    2012-10-01

    Full Text Available Background: Today, changing lifestyles, social relations and the advancement of technology causes fear, threats and concerns of different groups in society, especially students. Adverse impact of Anxiety on the efficacy and talents, personality and social identity formation of students, threat to achieve the goals of academic achievement and mental health. The present study was conducted to determine level of anxiety and some of their demographic correlates in the Alborz University of Medical Sciences in 1390. Methods: This study is a descriptive cross sectional study. The study population included all students of the Alborz university. 305 students were selected by stratified random sampling method. The data collection instrument was a demographic questionnaire and standardized Spielberger Anxiety Inventory. Data were analyzed using descriptive and inferential statistical methods. Results: Based on our results, 64 percent of students were anxious. Anxiety levels were significantly higher in men than women (p=0.049. The level of anxiety and interesting in medical course (p<0.001, non-academic study (p=0.007 and a major physical illness (p=0.009 had significant correlations with together. Conclusion: Results showed a high percentage of students anxious. Regarding the relation between anxiety and other problems such as depression and other disorders including failure in educational function, social relationships and lifestyle, Training courses on coping skills for anxiety and stress as well as consulting services and further guidance is recommended for them.

  8. An investigation of factors affecting elementary female student teachers' choice of science as a major at college level in Zimbabwe

    Science.gov (United States)

    Mlenga, Francis Howard

    The purpose of the study was to determine factors affecting elementary female student teachers' choice of science as a major at college level in Zimbabwe. The study was conducted at one of the Primary School Teachers' Colleges in Zimbabwe. A sample of two hundred and thirty-eight female student teachers was used in the study. Of these one hundred and forty-two were non-science majors who had been randomly selected, forty-one were science majors and forty-five were math majors. Both science and math majors were a convenient sample because the total enrollment of the two groups was small. All the subjects completed a survey questionnaire that had sixty-eight items. Ten students from the non-science majors were selected for individual interviews and the same was done for the science majors. A further eighteen were selected from the non-science majors and divided into three groups of six each for focus group interviews. The same was done for the science majors. The interviews were audio taped and transcribed. Data from the survey questionnaires were analyzed using Binary Logistic Regression which predicted factors that affected students' choice of science as a major. The transcribed interview data were analyzed used using domain, taxonomic and componential analyses. Results of the study indicated that elementary female students' choice of science as a major at college level is affected by students' attitudes toward science, teacher behavior, out-of-school experiences, role models, gender stereotyping, parental influence, peer influence, in-school experiences, and societal expectations, namely cultural and social expectations.

  9. Project of the Year Submittal SY-101 Surface Level Rise Remediation Project

    International Nuclear Information System (INIS)

    BAUER, R.E.

    2001-01-01

    CH2M HILL Hanford Group is pleased to nominate the SY-101 Surface Level Rise Remediation Project (SLRRP) for the Project Management Institute's consideration as International Project of the Year for 2001. We selected this project as being our best recent example of effective project management, having achieved and exceeded our client's expectations in resolving urgent safety issues related to the storage of high level nuclear waste. In reflection, we consider the SY-101 SLRRP to be a prime example of safe and effective project delivery. The pages that follow present the tools and techniques employed to manage this complex and technically challenging project. Our objective in submitting this nomination is twofold--to share the lessons we have learned with other organizations, and to honor the men and women who contributed to this endeavor. It was by their diligent effort that the successes we relate here were accomplished 10 months ahead of schedule and one million dollars below the authorized budget

  10. Effect of age and gender on the surface electromyogram during various levels of isometric contraction.

    Science.gov (United States)

    Arjunan, Sridhar; Kumar, Dinesh; Kalra, Chandan; Burne, John; Bastos, Teodiano

    2011-01-01

    This study reports the effects of age and gender on the surface electromyogram while performing isometric contraction. Experiments were conducted with two age groups--Young (Age: 20-29) and Old (Age: 60-69) where they performed sustained isometric contractions at various force levels (50%, 75%, 100% of maximum voluntary contraction). Traditional features such as root mean square (RMS) and median frequency (MDF) were computed from the recorded sEMG. The result indicates that the MDF of sEMG was not significantly affected by age, but was impacted by gender in both age groups. Also there was a significant change in the RMS of sEMG with age and gender at all levels of contraction. The results also indicate a large inter-subject variation. This study will provide an understanding of the underlying physiological effects of muscle contraction and muscle fatigue in different cohorts.

  11. Comparison pesticide residue levels in the surface of Bertam River in Cameron Highlands, Pahang

    Energy Technology Data Exchange (ETDEWEB)

    Haron, S. H., E-mail: ismail@ukm.edu.my; Ismail, B. S., E-mail: sthumaira@yahoo.com [School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia 43600 UKM, Bangi, Selangor (Malaysia)

    2015-09-25

    The presence of pesticide residues in the surface water of Bertam River in the agricultural areas of Cameron Highlands in Pahang, Malaysia was monitored from May to October 2014. The sampling sites were located at 10 sampling points along the Bertam River in the vegetable planting areas. The extraction method of the pesticide (organophosphate/pyrethroid) from the river samples used solid phase extraction followed by gas chromatography (with electron capture detector, ECD). Insecticides, cypermethrin and chlorpyrifos were found in the surface water of Bertam River. High level concentrations of those insecticides in the river were observed during the period from May to October 2014, a period which included both seasons (wet and dry seasons). The highest concentration of 2.66 µg/mL and 1.23 µg/mL of cypermethrin was observed during the wet and dry seasons respectively. This could be due to the frequent usage of the above-mentioned insecticides coupled with contamination that could have originated from the application sites. Meanwhile, the lowest concentration detected in the surface water was chlorpyrifos (0.11 µg/mL and 0.17 µg/mL) during the dry and wet seasons, respectively.

  12. Comparison pesticide residue levels in the surface of Bertam River in Cameron Highlands, Pahang

    International Nuclear Information System (INIS)

    Haron, S. H.; Ismail, B. S.

    2015-01-01

    The presence of pesticide residues in the surface water of Bertam River in the agricultural areas of Cameron Highlands in Pahang, Malaysia was monitored from May to October 2014. The sampling sites were located at 10 sampling points along the Bertam River in the vegetable planting areas. The extraction method of the pesticide (organophosphate/pyrethroid) from the river samples used solid phase extraction followed by gas chromatography (with electron capture detector, ECD). Insecticides, cypermethrin and chlorpyrifos were found in the surface water of Bertam River. High level concentrations of those insecticides in the river were observed during the period from May to October 2014, a period which included both seasons (wet and dry seasons). The highest concentration of 2.66 µg/mL and 1.23 µg/mL of cypermethrin was observed during the wet and dry seasons respectively. This could be due to the frequent usage of the above-mentioned insecticides coupled with contamination that could have originated from the application sites. Meanwhile, the lowest concentration detected in the surface water was chlorpyrifos (0.11 µg/mL and 0.17 µg/mL) during the dry and wet seasons, respectively

  13. A surface science compatible epifluorescence microscope for inspection of samples under ultra high vacuum and cryogenic conditions.

    Science.gov (United States)

    Marquardt, Christian; Paulheim, Alexander; Rohbohm, Nils; Merkel, Rudolf; Sokolowski, Moritz

    2017-08-01

    We modified an epi-illumination light microscope and mounted it on an ultra high vacuum chamber for investigating samples used in a surface science experiment. For easy access and bake out, all optical components are placed outside the vacuum and the sample is imaged through a glass window. The microscope can be operated in reflection brightfield or epifluorescence mode to image the sample surface or fluorescent dye molecules adsorbed on it. The homemade sample mounting was made compatible for the use under the microscope; sample temperatures as low as 6 K can be achieved. The performance of the microscope is demonstrated on two model samples: Brightfield-images of a well-prepared Ag(100) surface show a macroscopic corrugation of the surface, although low energy electron diffraction data indicate a highly ordered crystalline surface. The surface shows macroscopic protrusions with flat regions, about 20-200 μm in diameter, in between. Fluorescence images of diluted 3,4,9,10-perylene tetracarboxylicacid dianhydride (PTCDA) molecules adsorbed on an ultrathin epitaxial KCl film on the Ag(100) surface show a shading effect at surface protrusions due to an inclined angle of incidence of the PTCDA beam during deposition. For some preparations, the distribution of the fluorescence intensity is inhomogeneous and shows a dense network of bright patches about 5 μm in diameter related to the macroscopic corrugation of the surface. We propose that such a light microscope can aid many surface science experiments, especially those dealing with epitaxial growth or fluorescent materials.

  14. Self-consistent Green’s-function technique for bulk and surface impurity calculations: Surface core-level shifts by complete screening

    DEFF Research Database (Denmark)

    Aldén, M.; Abrikosov, I. A.; Johansson, B.

    1994-01-01

    of the frozen-core and atomic-sphere approximation but, in addition, includes the dipole contribution to the intersphere potential. Within the concept of complete screening, we identify the surface core-level binding-energy shift with the surface segregation energy of a core-ionized atom and use the Green......'s-function impurity technique in a comprehensive study of the surface core-level shifts (SCLS) of the 4d and 5d transition metals. In those cases, where observed data refer to single crystals, we obtain good agreement with experiment, whereas the calculations typically underestimate the measured shift obtained from...

  15. Robust space-time extraction of ventricular surface evolution using multiphase level sets

    Science.gov (United States)

    Drapaca, Corina S.; Cardenas, Valerie; Studholme, Colin

    2004-05-01

    This paper focuses on the problem of accurately extracting the CSF-tissue boundary, particularly around the ventricular surface, from serial structural MRI of the brain acquired in imaging studies of aging and dementia. This is a challenging problem because of the common occurrence of peri-ventricular lesions which locally alter the appearance of white matter. We examine a level set approach which evolves a four dimensional description of the ventricular surface over time. This has the advantage of allowing constraints on the contour in the temporal dimension, improving the consistency of the extracted object over time. We follow the approach proposed by Chan and Vese which is based on the Mumford and Shah model and implemented using the Osher and Sethian level set method. We have extended this to the 4 dimensional case to propagate a 4D contour toward the tissue boundaries through the evolution of a 5D implicit function. For convergence we use region-based information provided by the image rather than the gradient of the image. This is adapted to allow intensity contrast changes between time frames in the MRI sequence. Results on time sequences of 3D brain MR images are presented and discussed.

  16. Low-Cost Alternative for the Measurement of Water Levels in Surface Water Streams

    Directory of Open Access Journals (Sweden)

    Luis E. PEÑA

    2017-11-01

    Full Text Available Flood risk management and water resources planning involve a deep knowledge of surface streams so that mitigation strategies and climate change adaptations can be implemented. Commercially, there is a wide range of technologies for the measurement of hydroclimatic variables; however, many of these technologies may not be affordable for institutions with limited budgets. This paper has two main objectives: 1 Present the design of an ultrasound-based water level measurement system, and 2 Propose a methodological alternative for the development of instruments, according to the needs of institutions conducting monitoring of surface waterbodies. To that end, the proposed methodology is based on selection processes defined according to the specific needs of each waterbody. The prototype was tested in real-world scale, with the potential to obtain accurate measurements. Lastly, we present the design of the ultrasound-based water level measurement instrument, which can be built at a low cost. Low-cost instruments can potentially contribute to the sustainable instrumental autonomy of environmental entities and help define measurement and data transmission standards based on the specific requirements of the monitoring.

  17. Fabrication of Surface Level Cu/Si Cp Nano composites by Friction Stir Processing Route

    International Nuclear Information System (INIS)

    Srinivasan, R. C.; Karunanithi, M.

    2015-01-01

    Friction stir processing (FSP) technique has been successfully employed as low energy consumption route to prepare copper based surface level nano composites reinforced with nano sized silicon carbide particles (Si Cp). The effect of FSP parameters such as tool rotational speed, processing speed, and tool tilt angle on microstructure and microhardness was investigated. Single pass FSP was performed based on Box-Behnken design at three factors in three levels. A cluster of blind holes 2 mm in diameter and 3 mm in depth was used as particulate deposition technique in order to reduce the agglomeration problem during composite fabrication. K-type thermocouples were used to measure temperature histories during FSP. The results suggest that the heat generation during FSP plays a significant role in deciding the microstructure and microhardness of the surface composites. Microstructural observations revealed a uniform dispersion of nano sized Si Cp without any agglomeration problem and well bonded with copper matrix at different process parameter combinations. X-ray diffraction study shows that no intermetallic compound was produced after processing. The microhardness of nano composites was remarkably enhanced and about 95% more than that of copper matrix

  18. Fabrication of Surface Level Cu/SiCp Nanocomposites by Friction Stir Processing Route

    Directory of Open Access Journals (Sweden)

    Cartigueyen Srinivasan

    2015-01-01

    Full Text Available Friction stir processing (FSP technique has been successfully employed as low energy consumption route to prepare copper based surface level nanocomposites reinforced with nanosized silicon carbide particles (SiCp. The effect of FSP parameters such as tool rotational speed, processing speed, and tool tilt angle on microstructure and microhardness was investigated. Single pass FSP was performed based on Box-Behnken design at three factors in three levels. A cluster of blind holes 2 mm in diameter and 3 mm in depth was used as particulate deposition technique in order to reduce the agglomeration problem during composite fabrication. K-type thermocouples were used to measure temperature histories during FSP. The results suggest that the heat generation during FSP plays a significant role in deciding the microstructure and microhardness of the surface composites. Microstructural observations revealed a uniform dispersion of nanosized SiCp without any agglomeration problem and well bonded with copper matrix at different process parameter combinations. X-ray diffraction study shows that no intermetallic compound was produced after processing. The microhardness of nanocomposites was remarkably enhanced and about 95% more than that of copper matrix.

  19. Reduction Expansion Synthesis as Strategy to Control Nitrogen Doping Level and Surface Area in Graphene

    Directory of Open Access Journals (Sweden)

    Russell Canty

    2015-10-01

    Full Text Available Graphene sheets doped with nitrogen were produced by the reduction-expansion (RES method utilizing graphite oxide (GO and urea as precursor materials. The simultaneous graphene generation and nitrogen insertion reactions are based on the fact that urea decomposes upon heating to release reducing gases. The volatile byproducts perform two primary functions: (i promoting the reduction of the GO and (ii providing the nitrogen to be inserted in situ as the graphene structure is created. Samples with diverse urea/GO mass ratios were treated at 800 °C in inert atmosphere to generate graphene with diverse microstructural characteristics and levels of nitrogen doping. Scanning electron microscopy (SEM and transmission electron microscopy (TEM were used to study the microstructural features of the products. The effects of doping on the samples structure and surface area were studied by X-ray diffraction (XRD, Raman Spectroscopy, and Brunauer Emmet Teller (BET. The GO and urea decomposition-reduction process as well as nitrogen-doped graphene stability were studied by thermogravimetric analysis (TGA coupled with mass spectroscopy (MS analysis of the evolved gases. Results show that the proposed method offers a high level of control over the amount of nitrogen inserted in the graphene and may be used alternatively to control its surface area. To demonstrate the practical relevance of these findings, as-produced samples were used as electrodes in supercapacitor and battery devices and compared with conventional, thermally exfoliated graphene.

  20. PHOTOMETRIC STEREO SHAPE-AND-ALBEDO-FROM-SHADING FOR PIXEL-LEVEL RESOLUTION LUNAR SURFACE RECONSTRUCTION

    Directory of Open Access Journals (Sweden)

    W. C. Liu

    2017-07-01

    Full Text Available Shape and Albedo from Shading (SAfS techniques recover pixel-wise surface details based on the relationship between terrain slopes, illumination and imaging geometry, and the energy response (i.e., image intensity captured by the sensing system. Multiple images with different illumination geometries (i.e., photometric stereo can provide better SAfS surface reconstruction due to the increase in observations. Photometric stereo SAfS is suitable for detailed surface reconstruction of the Moon and other extra-terrestrial bodies due to the availability of photometric stereo and the less complex surface reflecting properties (i.e., albedo of the target bodies as compared to the Earth. Considering only one photometric stereo pair (i.e., two images, pixel-variant albedo is still a major obstacle to satisfactory reconstruction and it needs to be regulated by the SAfS algorithm. The illumination directional difference between the two images also becomes an important factor affecting the reconstruction quality. This paper presents a photometric stereo SAfS algorithm for pixel-level resolution lunar surface reconstruction. The algorithm includes a hierarchical optimization architecture for handling pixel-variant albedo and improving performance. With the use of Lunar Reconnaissance Orbiter Camera - Narrow Angle Camera (LROC NAC photometric stereo images, the reconstructed topography (i.e., the DEM is compared with the DEM produced independently by photogrammetric methods. This paper also addresses the effect of illumination directional difference in between one photometric stereo pair on the reconstruction quality of the proposed algorithm by both mathematical and experimental analysis. In this case, LROC NAC images under multiple illumination directions are utilized by the proposed algorithm for experimental comparison. The mathematical derivation suggests an illumination azimuthal difference of 90 degrees between two images is recommended to achieve

  1. The Development of the Nature of Science View Scale (NOSvs) at University Level

    Science.gov (United States)

    Temel, Senar; Sen, Senol; Özcan, Özgür

    2018-01-01

    Background: Determining individuals' views of the nature of science is quite important for researchers since it is both a component of scientific literacy and a fundamental aim of science education. Purpose: This study aims to develop a NOSvs for assessing prospective teachers' views of the nature of science and to analyse their psychometric…

  2. A high resolution photoemission study of surface core-level shifts in clean and oxygen-covered Ir(2 1 0) surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Gladys, M.J.; Ermanoski, I.; Jackson, G.; Quinton, J.S.; Rowe, J.E.; Madey, T.E. E-mail: madey@physics.rutgers.edu

    2004-04-01

    High resolution soft X-ray photoemission electron spectroscopy (SXPS), using synchrotron radiation, is employed to investigate 4f core-level features of four differently-prepared Ir(2 1 0) surfaces: clean planar, oxygen-covered planar, oxygen-induced faceted, and clean faceted surfaces. Surface and bulk peak identifications are supported by measurements at different photon energies (thus probing different electron escape depths) and variable emission angles. Iridium 4f{sub 7/2} photoemission spectra are fitted with Doniach-Sunjic lineshapes. The surface components are identified with core levels positioned at lower binding energies than the bulk components, in contrast to previous reports of binding energy inversion on Ir(1 0 0) (1x1) and (5x1) surfaces. For clean planar Ir(2 1 0) three surface Ir 4f{sub 7/2} features are observed with core-level shifts of -765, -529, and -281 meV, with respect to the bulk; these are associated with the first, second and third layers of atoms, respectively, for atomically rough Ir(2 1 0). Adsorption of oxygen onto the planar Ir(2 1 0) surface is found to cause a suppression and shift of the surface features to higher binding energies. Annealing at T{>=}600 K in oxygen produces a faceted surface as verified by low energy electron diffraction (LEED). A comparison of planar and faceted oxygen-covered surfaces reveals minor differences in the normal emission SXPS spectra, while grazing emission spectra exhibit differences. The SXPS spectrum of the clean, faceted Ir(2 1 0) exhibits small differences in comparison to the clean planar case, with surface features having binding energy shifts of -710, -450, and -230 meV.

  3. A Two-Ocean Bouillabaisse: Science, Politics, and the Central American Sea-Level Canal Controversy.

    Science.gov (United States)

    Keiner, Christine

    2017-11-01

    As the Panama Canal approached its fiftieth anniversary in the mid-1960s, U.S. officials concerned about the costs of modernization welcomed the technology of peaceful nuclear excavation to create a new waterway at sea level. Biologists seeking a share of the funds slated for radiological-safety studies called attention to another potential effect which they deemed of far greater ecological and evolutionary magnitude - marine species exchange, an obscure environmental issue that required the expertise of underresourced life scientists. An enterprising endeavor to support Smithsonian naturalists, especially marine biologists at the Smithsonian Tropical Research Institute in Panama, wound up sparking heated debates - between biologists and engineers about the oceans' biological integrity and among scientists about whether the megaproject represented a research opportunity or environmental threat. A National Academy of Sciences panel chaired by Ernst Mayr failed to attract congressional funding for its 10-year baseline research program, but did create a stir in the scientific and mainstream press about the ecological threats that the sea-level canal might unleash upon the Atlantic and Pacific. This paper examines how the proposed megaproject sparked a scientific and political conversation about the risks of mixing the oceans at a time when many members of the scientific and engineering communities still viewed the seas as impervious to human-facilitated change.

  4. Student-Life Stress Level and its Related Factors among Medical Students of Hamadan University of Medical Sciences in 2015

    OpenAIRE

    Roya Nikanjam; Majid Barati; Saeed Bashirian*; Mohammad Babamiri; Ali Fattahi; Alireza Soltanian

    2016-01-01

    Background and Objectives: Student-life stress can lead to various negative consequences such as physical illness, mental disorders or exhaustion. The present study was conducted to evaluate the level of student life stress and its related factors among medical students of Hamadan University of Medical Sciences. Materials and Methods: This cross-sectional study applied multistage random sampling to select 500university students at Hamadan University of Medical Sciences during 2015. The dat...

  5. Beyond The Prime Directive: The MAST Discovery Portal and High Level Science Products

    Science.gov (United States)

    Fleming, Scott W.; Abney, Faith; Donaldson, Tom; Dower, Theresa; Fraquelli, Dorothy A.; Koekemoer, Anton M.; Levay, Karen; Matuskey, Jacob; McLean, Brian; Quick, Lee; Rogers, Anthony; Shiao, Bernie; Thompson, Randy; Tseng, Shui-Ay; Wallace, Geoff; White, Richard L.

    2015-01-01

    The Mikulski Archive for Space Telescopes (MAST) is a NASA-funded archive for a wide range of astronomical missions, primarily supporting space-based UV and optical telescopes. What is less well-known is that MAST provides much more than just a final resting place for primary data products and documentation from these missions. The MAST Discovery Portal is our new search interface that integrates all the missions that MAST supports into a single interface, allowing users to discover (and retrieve) data from other missions that overlap with your targets of interest. In addition to searching MAST, the Portal allows users to search the Virtual Observatory, granting access to data from thousands of collections registered with the VO, including large missions spanning the electromagnetic spectrum (e.g., Chandra, SDSS, Spitzer, 2MASS, WISE). The Portal features table import/export, coordinate-based cross-matching, dynamic chart plotting, and the AstroView sky viewer with footprint overlays. We highlight some of these capabilities with science-driven examples. MAST also accepts High Level Science Products (HLSPs) from the community. These HLSPs are user-generated data products that can be related to a MAST-supported mission. MAST provides a permanent archive for these data with linked references, and integrates it within MAST infrastructure and services. We highlight some of the most recent HLSPs MAST has released, including the HST Frontier Fields, GALEX All-Sky Diffuse Radiation Mapping, a survey of the intergalactic medium with HST-COS, and one of the most complete line lists ever derived for a white dwarf using FUSE AND HST-STIS. These HLSPs generate substantial interest from the community, and are an excellent way to increase visibility and ensure the longevity of your data.

  6. Observations of the structure and evolution of surface and flight-level wind asymmetries in Hurricane Rita (2005)

    Science.gov (United States)

    Rogers, Robert; Uhlhorn, Eric

    2008-11-01

    Knowledge of the magnitude and distribution of surface winds, including the structure of azimuthal asymmetries in the wind field, are important factors for tropical cyclone forecasting. With its ability to remotely measure surface wind speeds, the stepped frequency microwave radiometer (SFMR) has assumed a prominent role for the operational tropical cyclone forecasting community. An example of this instrument's utility is presented here, where concurrent measurements of aircraft flight-level and SFMR surface winds are used to document the wind field evolution over three days in Hurricane Rita (2005). The amplitude and azimuthal location (phase) of the wavenumber-1 asymmetry in the storm-relative winds varied at both levels over time. The peak was found to the right of storm track at both levels on the first day. By the third day, the peak in flight-level storm-relative winds remained to the right of storm track, but it shifted to left of storm track at the surface, resulting in a 60-degree shift between the surface and flight-level and azimuthal variations in the ratio of surface to flight-level winds. The asymmetric differences between the surface and flight-level maximum wind radii also varied, indicating a vortex whose tilt was increasing.

  7. Statistical characterization of global Sea Surface Salinity for SMOS level 3 and 4 products

    Science.gov (United States)

    Gourrion, J.; Aretxabaleta, A. L.; Ballabrera, J.; Mourre, B.

    2009-04-01

    The Soil Moisture and Ocean Salinity (SMOS) mission of the European Space Agency will soon provide sea surface salinity (SSS) estimates to the scientific community. Because of the numerous geophysical contamination sources and the instrument complexity, the salinity products will have a low signal to noise ratio at level 2 (individual estimates??) that is expected to increase up to mission requirements (0.1 psu) at level 3 (global maps with regular distribution) after spatio-temporal accumulation of the observations. Geostatistical methods such as Optimal Interpolation are being implemented at the level 3/4 production centers to operate this noise reduction step. The methodologies require auxiliary information about SSS statistics that, under Gaussian assumption, consist in the mean field and the covariance of the departures from it. The present study is a contribution to the definition of the best estimates for mean field and covariances to be used in the near-future SMOS level 3 and 4 products. We use complementary information from sparse in-situ observations and imperfect outputs from state-of-art model simulations. Various estimates of the mean field are compared. An alternative is the use of a SSS climatology such as the one provided by the World Ocean Atlas 2005. An historical SSS dataset from the World Ocean Database 2005 is reanalyzed and combined with the recent global observations obtained by the Array for Real-Time Geostrophic Oceanography (ARGO). Regional tendencies in the long-term temporal evolution of the near-surface ocean salinity are evident, suggesting that the use of a SSS climatology to describe the current mean field may introduce biases of magnitude similar to the precision goal. Consequently, a recent SSS dataset may be preferred to define the mean field needed for SMOS level 3 and 4 production. The in-situ observation network allows a global mapping of the low frequency component of the variability, i.e. decadal, interannual and seasonal

  8. Functional levels of floor surface roughness for the prevention of slips and falls: clean-and-dry and soapsuds-covered wet surfaces.

    Science.gov (United States)

    Kim, In-Ju; Hsiao, Hongwei; Simeonov, Peter

    2013-01-01

    Literature has shown a general trend that slip resistance performance improves with floor surface roughness. However, whether slip resistance properties are linearly correlated with surface topographies of the floors or what roughness levels are required for effective slip resistance performance still remain to be answered. This pilot study aimed to investigate slip resistance properties and identify functional levels of floor surface roughness for practical design applications in reducing the risk of slip and fall incidents. A theory model was proposed to characterize functional levels of surface roughness of floor surfaces by introducing a new concept of three distinctive zones. A series of dynamic friction tests were conducted using 3 shoes and 9 floor specimens under clean-and-dry as well as soapsuds-covered slippery wet environments. The results showed that all the tested floor-shoe combinations provided sufficient slip resistances performance under the clean-and-dry condition. A significant effect of floor type (surface roughness) on dynamic friction coefficient (DFC) was found in the soapsuds-covered wet condition. As compared to the surface roughness effects, the shoe-type effects were relatively small. Under the soapsuds-covered wet condition, floors with 50 μm in Ra roughness scale seemed to represent an upper bound in the functional range of floor surface roughness for slip resistance because further increase of surface roughness provided no additional benefit. A lower bound of the functional range for slip resistance under the soapsuds-covered wet condition was estimated from the requirement of DFC > 0.4 at Ra ≅ 17 μm. Findings from this study may have potential safety implications in the floor surface design for reducing slip and fall hazards. Published by Elsevier Ltd.

  9. Ethers on Si(001): A prime example for the common ground between surface science and molecular organic chemistry

    KAUST Repository

    Pecher, Lisa

    2017-09-15

    Using computational chemistry, we show that the adsorption of ether molecules on Si(001) under ultra-high vacuum conditions can be understood with textbook organic chemistry. The two-step reaction mechanism of (1) dative bond formation between the ether oxygen and a Lewis acidic surface atom and (2) a nucleophilic attack of a nearby Lewis basic surface atom is analysed in detail and found to mirror the acid-catalysed ether cleavage in solution. The O-Si dative bond is found to be the strongest of its kind and reactivity from this state defies the Bell-Evans-Polanyi principle. Electron rearrangement during the C-O bond cleavage is visualized using a newly developed bonding analysis method, which shows that the mechanism of nucleophilic substitutions on semiconductor surfaces is identical to molecular chemistry SN2 reactions. Our findings thus illustrate how the fields of surface science and molecular chemistry can mutually benefit and unexpected insight can be gained.

  10. Ethers on Si(001): A prime example for the common ground between surface science and molecular organic chemistry

    KAUST Repository

    Pecher, Lisa; Laref, Slimane; Raupach, Marc; Tonner, Ralf Ewald

    2017-01-01

    Using computational chemistry, we show that the adsorption of ether molecules on Si(001) under ultra-high vacuum conditions can be understood with textbook organic chemistry. The two-step reaction mechanism of (1) dative bond formation between the ether oxygen and a Lewis acidic surface atom and (2) a nucleophilic attack of a nearby Lewis basic surface atom is analysed in detail and found to mirror the acid-catalysed ether cleavage in solution. The O-Si dative bond is found to be the strongest of its kind and reactivity from this state defies the Bell-Evans-Polanyi principle. Electron rearrangement during the C-O bond cleavage is visualized using a newly developed bonding analysis method, which shows that the mechanism of nucleophilic substitutions on semiconductor surfaces is identical to molecular chemistry SN2 reactions. Our findings thus illustrate how the fields of surface science and molecular chemistry can mutually benefit and unexpected insight can be gained.

  11. Improving Limit Surface Search Algorithms in RAVEN Using Acceleration Schemes: Level II Milestone

    Energy Technology Data Exchange (ETDEWEB)

    Alfonsi, Andrea [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Rabiti, Cristian [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Mandelli, Diego [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Cogliati, Joshua Joseph [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Sen, Ramazan Sonat [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Smith, Curtis Lee [Idaho National Laboratory (INL), Idaho Falls, ID (United States)

    2015-07-01

    , subject of the analysis. These methodologies are named, in the RAVEN environment, adaptive sampling strategies. These methodologies infer system responses from surrogate models constructed from already existing samples (produced using high fidelity simulations) and suggest the most relevant location (coordinate in the input space) of the next sampling point to be explored in the uncertain/parametric domain. When using those methodologies, it is possible to understand features of the system response with a small number of carefully selected samples. This report focuses on the development and improvement of the limit surface search. The limit surface is an important concept in system reliability analysis. Without going into the details, which will be covered later in the report, the limit surface could be briefly described as an hyper-surface in the system uncertainty/parametric space separating the regions leading to a prescribed system outcome. For example, if the uncertainty/parametric space is the one generated by the reactor power level and the duration of the batteries, the system is a nuclear power plant and the system outcome discriminating variable is the clad failure in a station blackout scenario, then the limit surface separates the combinations of reactor power level and battery duration that lead to clad failure from the ones that do not.

  12. Facet personality and surface-level diversity as team mental model antecedents: implications for implicit coordination.

    Science.gov (United States)

    Fisher, David M; Bell, Suzanne T; Dierdorff, Erich C; Belohlav, James A

    2012-07-01

    Team mental models (TMMs) have received much attention as important drivers of effective team processes and performance. Less is known about the factors that give rise to these shared cognitive structures. We examined potential antecedents of TMMs, with a specific focus on team composition variables, including various facets of personality and surface-level diversity. Further, we examined implicit coordination as an important outcome of TMMs. Results suggest that team composition in terms of the cooperation facet of agreeableness and racial diversity were significantly related to team-focused TMM similarity. TMM similarity was also positively predictive of implicit coordination, which mediated the relationship between TMM similarity and team performance. Post hoc analyses revealed a significant interaction between the trust facet of agreeableness and racial diversity in predicting TMM similarity. Results are discussed in terms of facilitating the emergence of TMMs and corresponding implications for team-related human resource practices. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

  13. Selection of replacement material for the failed surface level gauge wire in Hanford waste tanks

    International Nuclear Information System (INIS)

    Anantatmula, R.P.; Pitman, S.G.; Lund, A.L.

    1995-10-01

    Surface level gauges fabricated from AISI Type 316 stainless steel (316) wire failed after only a few weeks of operation in underground storage tanks at the Hanford Site. The wire failure was determined to be due to chloride ion assisted corrosion of the 316 wire. Radiation-induced breakdown of the polyvinyl chloride (PVC) riser liners is suspected to be the primary source of the chloride ions. An extensive literature search followed by expert concurrence was undertaken to select a replacement material for the wire. Platinum (Pt)-20 % Iridium (Ir) alloy was selected as the replacement material from tile candidate materials, P-20% Ir, Pt-1O% Rhodium (Rh), Pt-20%Rh and Hastelloy C-22. The selection was made on the basis of the alloy's immunity towards acidic and basic environments as well as its adequate tensile properties in the fully annealed state

  14. Energy pumping analysis of skating motion in a half pipe and on a level surface

    Science.gov (United States)

    Feng, Z. C.; Xin, Ming

    2015-01-01

    In this paper, an energy pumping mechanism for locomotion is analysed. The pumping is accomplished by exerting forces perpendicular to the direction of motion. The paper attempts to demonstrate an interesting application of the classical mechanics to two sporting events: a person skating in a half pipe and a person travelling on a level surface on a skateboard. The equations of motion based on simplified mechanical models are derived using the Lagrange mechanics. The energy-pumping phenomenon is revealed through numerical simulations with simple pumping actions. The result presented in this paper can be used as an interesting class project in undergraduate mechanics or physics courses. It also motivates potential new applications of energy pumping in many engineering fields.

  15. Energy pumping analysis of skating motion in a half pipe and on a level surface

    International Nuclear Information System (INIS)

    Feng, Z C; Xin, Ming

    2015-01-01

    In this paper, an energy pumping mechanism for locomotion is analysed. The pumping is accomplished by exerting forces perpendicular to the direction of motion. The paper attempts to demonstrate an interesting application of the classical mechanics to two sporting events: a person skating in a half pipe and a person travelling on a level surface on a skateboard. The equations of motion based on simplified mechanical models are derived using the Lagrange mechanics. The energy-pumping phenomenon is revealed through numerical simulations with simple pumping actions. The result presented in this paper can be used as an interesting class project in undergraduate mechanics or physics courses. It also motivates potential new applications of energy pumping in many engineering fields. (paper)

  16. Low level chemiluminescence measurement of the binding of 8-methoxypsoralen to proteins and lymphocytic surfaces

    International Nuclear Information System (INIS)

    Lange, B.

    1980-01-01

    Photochemotherapy with 8-methoxypsoralen (8-MOP) and longwave ultraviolet light is beneficial in such different disorders like psoriasis, lichen planus, and mykosis fungoides. In contrast to a widely accepted hypothesis 8-MOP does not solely bind to nucleic acid, but also to certain proteins. The mechanism of this binding as well as the precise binding area are unknown. Therefore the UV-provoked reactions of 8-MOP with a lipid mixture, a glucosaminoglycan solution, a protein solution, and lymphocyte suspensions, respectively were investigated using low level chemiluminescence (LLCL). It was found an 8-MOP concentration-dependent decrease of LLCL intensity in the lymphocyte suspensions (10 3 to 10 4 cells/μl). This effect is result of the diminution of the photoactive 8-MOP content of the solution. 8-MOP binds quickly and in the course of a free radical reaction to lymphocytic surfaces and coincidentally loses its potency to start LLCL-detectable free radical chain responses. (author)

  17. Scientific and technical basis for the near surface disposal of low and intermediate level waste

    International Nuclear Information System (INIS)

    2002-01-01

    This report presents an overview of the scientific and technical basis for the disposal of low- and intermediate-level radioactive waste in near surface repositories. The focus is on basic principles, approaches, methodologies and technical criteria that can be used to develop and assess the performance of a disposal facility, and for building confidence in repository safety. This includes consideration of the multiple barrier concept, the performance of engineered barriers, the role of natural barriers and the development of a safety case. The emphasis is on defining the conditions relevant to the containment of the radionuclides in the repository and the processes that may affect the integrity of the engineered barriers. Both generic and specific data requirements for repository development and the assurance of safety are addressed. A large number of bibliographical references are given to support the information provided in this report

  18. Evaluation of pressure transducers to measure surface level in the waste storage tanks

    International Nuclear Information System (INIS)

    Peters, T.J.; Colson, J.B.

    1994-06-01

    This report describes the results of tests conducted at the Pacific Northwest Laboratory (PNL) to determine if pressure transducers can be used to measure the surface level in the waste tanks. A survey was first conducted to evaluate which, if any, commercially available pressure transducers were available that could meet the requirements for use in the waste tanks. More than 35 companies were contacted to determine if they manufactured a pressure transducer that could be used in the 101-SY waste tank. The three basic requirements for a pressure transducer for this application were that they were radiation-hardened, could withstand a caustic environment, and were certified to be intrinsically safe. No manufacturer was able to meet all three of these requirements with a commercially available product. Seven companies were able to meet the requirements for being radiation-hardened and being able to withstand the caustic environment. However, only two of the nine companies were willing to supply a pressure transducer for laboratory testing. The two pressure transducers that were tested in this program were the VEGA D36-38 from HiTech Technologies, Inc., and the KP-1911-A from Kaman Instrumentation Corporation. Pressure transducers operate on the principle that the pressure at the location of a sensor increases directly with the depth of the liquid above it. A liquid is required in order for these devices to operate. For these tests, water was first used to determine the ideal operation of the devices, then the devices were placed in a 101-SY waste tank simulant. The simulant had a specific gravity of 1.96 and had the consistency similar to the convective layer in the 101-SY waste tank. In order to determine the surface level with pressure transducers, the density of the material needs to be known

  19. Near-surface storage facilities for vitrified high-level wastes

    International Nuclear Information System (INIS)

    Kondrat'ev, A.N.; Kulichenko, V.V.; Kryukov, I.I.; Krylova, N.V.; Paramoshkin, V.I.; Strakhov, M.V.

    1980-01-01

    Concurrently with the development of methods for solidifying liquid radioactive wastes, reliable and safe methods for the storage and disposal of solidified wastes are being devised in the USSR and other countries. One of the main factors affecting the choice of storage conditions for solidified wastes originating from the vitrification of high-level liquid wastes from fuel reprocessing plants is the problem of removing the heat produced by radioactive decay. In order to prevent the temperature of solidified wastes from exceeding the maximum permissible level for the material concerned, it is necessary to limit either the capacity of waste containers or the specific heat release of the wastes themselves. In order that disposal of high-level wastes in geological formations should be reliable and economic, solidified wastes undergo interim storage in near-surface storage facilities with engineered cooling systems. The paper demonstrates the relative influences of specific heat release, of the maximum permissible storage temperature for vitrified wastes and of the methods chosen for cooling wastes in order for the dimensions of waste containers to be reduced to the extent required. The effect of concentrating wastes to a given level in the vitrification process on the cost of storage in different types of storage facility is also examined. Calculations were performed for the amount of vitrified wastes produced by a reprocessing plant with a capacity of five tonnes of uranium per 24 hours. Fuel elements from reactors of the water-cooled, water-moderated type are sent for reprocessing after having been held for about two years. The dimensions of the storage facility are calculated on the assumption that it will take five years to fill

  20. The teacher's role in college level classes for non-science majors: A constructivist approach for teaching prospective science teachers

    Science.gov (United States)

    Abbas, Abdullah Othman

    1997-12-01

    This interpretive research set out to investigate the characteristics of an exemplary college science instructor who endeavors to improve teaching and learning in a physical science course for prospective teachers. The course was innovative in the sense that it was designed to meet the specific needs of prospective elementary teachers who needed to have models of how to teach science in a way that employed materials and small group activities. The central purpose for this study is to understand the metaphors that Mark (a pseudonym), the chemistry instructor in the course, used as referents to conceptualize his roles and frame actions and interactions in the classroom. Within the theoretical frame of constructivism, human cognitive interests, and co-participation theories, an ethnographic research design, described by Erickson (1986), Guba and Lincoln (1989), and Gallagher (1991), was employed in the study. The main sources of data for this study were field notes, transcript analysis of interviews with the instructor and students, and analyses of videotaped excerpts. Additional data sources, such as student journals and the results of students' responses to the University/Community College Student Questionnaire which was developed by a group science education researchers at Florida State University, were employed to maximize that the assertions I constructed were consistent with the variety of data. Data analyses and interpretation in the study focused on identifying the aspects which the instructor and the researcher might find useful in reflecting to understand what was happening and why that was happening in the classroom. The analysis reveals how the instructor used constructivism as a referent for his teaching and the learning of his students. To be consistent with his beliefs and goals that prospective teachers should enjoy their journey of learning chemistry, Mark, the driver in the journey, used the roles of controller, facilitator, learner, and entertainer

  1. Effects of multisensory resources on the achievement and science attitudes of seventh-grade suburban students taught science concepts on and above grade level

    Science.gov (United States)

    Roberts, Patrice Helen

    This research was designed to determine the relationships among students' achievement scores on grade-level science content, on science content that was three years above-grade level, on attitudes toward instructional approaches, and learning-styles perceptual preferences when instructional approaches were multisensory versus traditional. The dependent variables for this investigation were scores on achievement posttests and scores on the attitude survey. The independent variables were the instructional strategy and students' perceptual preferences. The sample consisted of 74 educationally oriented seventh-grade students. The Learning Styles Inventory (LSI) (Dunn, Dunn, & Price, 1990) was administered to determine perceptual preferences. The control group was taught seventh-grade and tenth-grade science units using a traditional approach and the experimental group was instructed on the same units using multisensory instructional resources. The Semantic Differential Scale (SDS) (Pizzo, 1981) was administered to reveal attitudinal differences. The traditional unit included oral reading from the textbook, completing outlines, labeling diagrams, and correcting the outlines and diagrams as a class. The multisensory unit included five instructional stations established in different sections of the classroom to allow students to learn by: (a) manipulating Flip Chutes, (b) using Electroboards, (c) assembling Task Cards, (d) playing a kinesthetic Floor Game, and (e) reading an individual Programmed Learning Sequence. Audio tapes and scripts were provided at each location. Students circulated in groups of four from station to station. The data subjected to statistical analyses supported the use of a multisensory, rather than a traditional approach, for teaching science content that is above-grade level. T-tests revealed a positive and significant impact on achievement scores (p < 0.0007). No significance was detected on grade-level achievement nor on the perceptual

  2. Web Monitoring of EOS Front-End Ground Operations, Science Downlinks and Level 0 Processing

    Science.gov (United States)

    Cordier, Guy R.; Wilkinson, Chris; McLemore, Bruce

    2008-01-01

    This paper addresses the efforts undertaken and the technology deployed to aggregate and distribute the metadata characterizing the real-time operations associated with NASA Earth Observing Systems (EOS) high-rate front-end systems and the science data collected at multiple ground stations and forwarded to the Goddard Space Flight Center for level 0 processing. Station operators, mission project management personnel, spacecraft flight operations personnel and data end-users for various EOS missions can retrieve the information at any time from any location having access to the internet. The users are distributed and the EOS systems are distributed but the centralized metadata accessed via an external web server provide an effective global and detailed view of the enterprise-wide events as they are happening. The data-driven architecture and the implementation of applied middleware technology, open source database, open source monitoring tools, and external web server converge nicely to fulfill the various needs of the enterprise. The timeliness and content of the information provided are key to making timely and correct decisions which reduce project risk and enhance overall customer satisfaction. The authors discuss security measures employed to limit access of data to authorized users only.

  3. Effect of levels of inquiry model of science teaching on scientific literacy domain attitudes

    Science.gov (United States)

    Achmad, Maulana; Suhandi, Andi

    2017-05-01

    The aim of this research was to obtain an overview of the increase scientific literacy attitudes domain in high school students as the effects of the Levels of Inquiry (LOI) model of science teaching. This research using a quasi-experimental methods and randomizedpretest-posttest control group design. The subject of this research was students of grade X in a senior high school in Purwakarta and it consists of two classes who were divided into experimental class (30 students) and control class (30 students). While experimental class was taught LOIand control class was taught Interactive Lecture Demonstration (ILD). Data were collected using an attitude scale scientific literacy test which is based on the Likert scale. Data were analyzed using normality test, homogeneity test, and t-test to the value of N-gain attitude of scientific literacy scale test. The result of percentage average N-gain experimental class and control are 49 and 31 that classified into medium improvement category. Based on the results of hypothesis testing on the N-gain value obtained by the Sig.(One-tailed) 0.000 < 0.050, it means that H1 was accepted. The results showed that scientific literacy domain attitude of students who got learning by LOI is higher than students who got learning by ILD. It can be concluded that the effect of LOI is better to improve scientific literacy domain attitudes significantly.

  4. Assessment of the SMAP Level-4 Surface and Root-Zone Soil Moisture Product Using In Situ Measurements

    NARCIS (Netherlands)

    Reichle, Rolf H.; De Lannoy, Gabrielle J. M.; Liu, Qing; Ardizzone, Joseph V.; Colliander, Andreas; Conaty, Austin; Crow, Wade; Jackson, Thomas J.; Jones, Lucas A.; Kimball, John S.; Koster, Randal D.; Mahanama, Sarith P.; Smith, Edmond B.; Berg, Aaron; Bircher, Simone; Bosch, David; Caldwell, Todd G.; Cosh, Michael; Holifield Collins, Chandra D.; Jensen, Karsten H.; Livingston, Stan; Lopez-baeza, Ernesto; Martínez-fernández, José; Mcnairn, Heather; Moghaddam, Mahta; Pacheco, Anna; Pellarin, Thierry; Prueger, John; Rowlandson, Tracy; Seyfried, Mark; Starks, Patrick; Su, Bob; Thibeault, Marc; Van Der Velde, Rogier; Walker, Jeffrey; Wu, Xiaoling; Zeng, Yijian

    2017-01-01

    The Soil Moisture Active Passive (SMAP) mission Level-4 Surface and Root-Zone Soil Moisture (L4_SM) data product is generated by assimilating SMAP L-band brightness temperature observations into the NASA Catchment land surface model. The L4_SM product is available from 31 March 2015 to present

  5. OMI/Aura Surface Reflectance Climatology Level 3 Global 0.5deg Lat/Lon Grid V003

    Data.gov (United States)

    National Aeronautics and Space Administration — The OMI Earth Surface Reflectance Climatology product, OMLER (Global 0.5deg Lat/Lon grid) which is based on Version 003 Level-1B top of atmosphere upwelling radiance...

  6. Genus- and species-level identification of dermatophyte fungi by surface-enhanced Raman spectroscopy

    Science.gov (United States)

    Witkowska, Evelin; Jagielski, Tomasz; Kamińska, Agnieszka

    2018-03-01

    This paper demonstrates that surface-enhanced Raman spectroscopy (SERS) coupled with principal component analysis (PCA) can serve as a fast and reliable technique for detection and identification of dermatophyte fungi at both genus and species level. Dermatophyte infections are the most common mycotic diseases worldwide, affecting a quarter of the human population. Currently, there is no optimal method for detection and identification of fungal diseases, as each has certain limitations. Here, for the first time, we have achieved with a high accuracy, differentiation of dermatophytes representing three major genera, i.e. Trichophyton, Microsporum, and Epidermophyton. Two first principal components (PC), namely PC-1 and PC-2, gave together 97% of total variance. Additionally, species-level identification within the Trichophyton genus has been performed. PC-1 and PC-2, which are the most diagnostically significant, explain 98% of the variance in the data obtained from spectra of: Trichophyton rubrum, Trichophyton menatgrophytes, Trichophyton interdigitale and Trichophyton tonsurans. This study offers a new diagnostic approach for the identification of dermatophytes. Being fast, reliable and cost-effective, it has the potential to be incorporated in the clinical practice to improve diagnostics of medically important fungi.

  7. A Continuous Liquid-Level Sensor for Fuel Tanks Based on Surface Plasmon Resonance

    Directory of Open Access Journals (Sweden)

    Antonio M. Pozo

    2016-05-01

    Full Text Available A standard problem in large tanks at oil refineries and petrol stations is that water and fuel usually occupy the same tank. This is undesirable and causes problems such as corrosion in the tanks. Normally, the water level in tanks is unknown, with the problems that this entails. We propose herein a method based on surface plasmon resonance (SPR to detect in real time the interfaces in a tank which can simultaneously contain water, gasoline (or diesel and air. The plasmonic sensor is composed of a hemispherical glass prism, a magnesium fluoride layer, and a gold layer. We have optimized the structural parameters of the sensor from the theoretical modeling of the reflectance curve. The sensor detects water-fuel and fuel-air interfaces and measures the level of each liquid in real time. This sensor is recommended for inflammable liquids because inside the tank there are no electrical or electronic signals which could cause explosions. The sensor proposed has a sensitivity of between 1.2 and 3.5 RIU−1 and a resolution of between 5.7 × 10−4 and 16.5 × 10−4 RIU.

  8. Seventh BES [Basic Energy Sciences] catalysis and surface chemistry research conference

    International Nuclear Information System (INIS)

    1990-03-01

    Research programs on catalysis and surface chemistry are presented. A total of fifty-seven topics are included. Areas of research include heterogeneous catalysis; catalysis in hydrogenation, desulfurization, gasification, and redox reactions; studies of surface properties and surface active sites; catalyst supports; chemical activation, deactivation; selectivity, chemical preparation; molecular structure studies; sorption and dissociation. Individual projects are processed separately for the data bases

  9. Seventh BES (Basic Energy Sciences) catalysis and surface chemistry research conference

    Energy Technology Data Exchange (ETDEWEB)

    1990-03-01

    Research programs on catalysis and surface chemistry are presented. A total of fifty-seven topics are included. Areas of research include heterogeneous catalysis; catalysis in hydrogenation, desulfurization, gasification, and redox reactions; studies of surface properties and surface active sites; catalyst supports; chemical activation, deactivation; selectivity, chemical preparation; molecular structure studies; sorption and dissociation. Individual projects are processed separately for the data bases. (CBS)

  10. Constraining the JULES land-surface model for different land-use types using citizen-science generated hydrological data

    Science.gov (United States)

    Chou, H. K.; Ochoa-Tocachi, B. F.; Buytaert, W.

    2017-12-01

    Community land surface models such as JULES are increasingly used for hydrological assessment because of their state-of-the-art representation of land-surface processes. However, a major weakness of JULES and other land surface models is the limited number of land surface parameterizations that is available. Therefore, this study explores the use of data from a network of catchments under homogeneous land-use to generate parameter "libraries" to extent the land surface parameterizations of JULES. The network (called iMHEA) is part of a grassroots initiative to characterise the hydrological response of different Andean ecosystems, and collects data on streamflow, precipitation, and several weather variables at a high temporal resolution. The tropical Andes are a useful case study because of the complexity of meteorological and geographical conditions combined with extremely heterogeneous land-use that result in a wide range of hydrological responses. We then calibrated JULES for each land-use represented in the iMHEA dataset. For the individual land-use types, the results show improved simulations of streamflow when using the calibrated parameters with respect to default values. In particular, the partitioning between surface and subsurface flows can be improved. But also, on a regional scale, hydrological modelling was greatly benefitted from constraining parameters using such distributed citizen-science generated streamflow data. This study demonstrates the modelling and prediction on regional hydrology by integrating citizen science and land surface model. In the context of hydrological study, the limitation of data scarcity could be solved indeed by using this framework. Improved predictions of such impacts could be leveraged by catchment managers to guide watershed interventions, to evaluate their effectiveness, and to minimize risks.

  11. Comparisons of predicted steady-state levels in rooms with extended- and local-reaction bounding surfaces

    Science.gov (United States)

    Hodgson, Murray; Wareing, Andrew

    2008-01-01

    A combined beam-tracing and transfer-matrix model for predicting steady-state sound-pressure levels in rooms with multilayer bounding surfaces was used to compare the effect of extended- and local-reaction surfaces, and the accuracy of the local-reaction approximation. Three rooms—an office, a corridor and a workshop—with one or more multilayer test surfaces were considered. The test surfaces were a single-glass panel, a double-drywall panel, a carpeted floor, a suspended-acoustical ceiling, a double-steel panel, and glass fibre on a hard backing. Each test surface was modeled as of extended or of local reaction. Sound-pressure levels were predicted and compared to determine the significance of the surface-reaction assumption. The main conclusions were that the difference between modeling a room surface as of extended or of local reaction is not significant when the surface is a single plate or a single layer of material (solid or porous) with a hard backing. The difference is significant when the surface consists of multilayers of solid or porous material and includes a layer of fluid with a large thickness relative to the other layers. The results are partially explained by considering the surface-reflection coefficients at the first-reflection angles.

  12. Occurrence and levels of polybrominated diphenyl ethers in surface sediments from the Yellow River Estuary, China.

    Science.gov (United States)

    Yuan, Zijiao; Liu, Guijian; Lam, Michael Hon Wah; Liu, Houqi; Da, Chunnian

    2016-05-01

    A total of 21 surface sediments collected from the Yellow River Estuary, China were analyzed for 40 kinds of polybrominated diphenyl ethers (PBDEs) using gas chromatography-mass spectrometry (GC-MS). Their levels, spatial distribution, congener profiles and possible sources were investigated. Only ten congeners were detected in the sediments. The total concentrations of the lower brominated BDEs (∑PBDEslow, PBDEs excluding BDE 209) and BDE 209 ranged from 0.482 ng/g to 1.07 ng/g and 1.16-5.40 ng/g, with an average value of 0.690 and 2.79 ng/g, respectively, which were both at the low end of the global contamination level. The congener profiles were dominated by BDE 209, with the average value accounting for 79.2% of the total PBDEs in the sediment samples. Among the nine lower brominated BDE congeners, BDE 47, 99 and 183 had high abundances. Although the commercial Penta/Octa-BDE products have been banned in most countries, the residual commercial Penta/Octa/Deca-BDE products and the debromination of highly brominated BDE compounds such as BDE 209 were still found to be the possible sources for the trace level of PBDEs in the present study area. In spite of the gradual removal of the commercial PBDEs in the world, the present research results further suggested that scientific attention should not be reduced on the issue of environmental contamination caused by these outdated chemical compounds. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Science Seeker: A New Model for Teaching Information Literacy to Entry-Level Biology Undergraduates

    Science.gov (United States)

    Petzold, Jacquelyn; Winterman, Brian; Montooth, Kristi

    2010-01-01

    In order to integrate library instruction seamlessly into an introductory biology course, two librarians collaborated with a biology faculty member to create a three-part series of instruction sessions known as the Science Seeker. The Science Seeker taught students about the structure of scientific information by tracing the path that discoveries…

  14. Powerful Partnerships: The Worth of Embedding Masters Level Library Science Students in Undergraduate Classes

    Science.gov (United States)

    Becnel, Kim; Moeller, Robin A.; Pope, Jon C.

    2016-01-01

    While experiential learning is recognized as an important pedagogical approach in Library and Information Science education, logistical hurdles can make implementing meaningful experiential projects challenging, especially in online courses. This paper will describe a project in which Library Science instructors were able to overcome common…

  15. Classroom management at the university level: lessons from a former high school earth science teacher

    Science.gov (United States)

    Lazar, C.

    2009-12-01

    Just a few days before my career as a fledgling science teacher began in a large public high school in New York City, a mentor suggested I might get some ideas about how to run a classroom from a book called The First Days Of School by Harry Wong. Although the book seemed to concentrate more on elementary students, I found that many of the principles in the book worked well for high school students. Even as I have begun to teach at the university level, many of Wong’s themes have persisted in my teaching style. Wong’s central thesis is that for learning to occur, a teacher must create the proper environment. In education jargon, a good climate for learning is generated via classroom management, an array of methods used by elementary and secondary school teachers to provide structure and routine to a class period via a seamless flow of complementary activities. Many college professors would likely consider classroom management to be chiefly a set of rules to maintain discipline and order among an otherwise unruly herd of schoolchildren, and therefore not a useful concept for mature university students. However, classroom management is much deeper than mere rules for behavior; it is an approach to instructional design that considers the classroom experience holistically. A typical professorial management style is to lecture for an hour or so and ask students to demonstrate learning via examinations several times in a semester. In contrast, a good high school teacher will manage a class from bell-to-bell to create a natural order and flow to a given lesson. In this presentation, I will argue for an approach to college lesson design similar to the classroom management style commonly employed by high school and elementary school teachers. I will suggest some simple, practical techniques learned during my high school experience that work just as well in college: warm-up and practice problems, time management, group activities, bulletin boards, learning environment

  16. Population-level assessments should be emphasized over community/ecosystem-level assessments. Environmental Sciences Division Publication No. 1535

    International Nuclear Information System (INIS)

    Van Winkle, W.

    1980-01-01

    Arguments are presented in favor of emphasizing population-level assessments over community/ecosystem-level assessments. The two approaches are compared on each of four issues: (1) the nature of entrainment/impingement impacts; (2) the ability to forecast reliably for a single fish population as contrasted to the ability to forecast for an aquatic community or ecosystem; (3) practical considerations involving money, manpower, time, and the need to make decisions; and (4) the nature of societal and economic concerns. The conclusion on each of these four issues is that population-level assessments provide the optimal approach for evaluating the effects of entrainment and impingement mortality

  17. Comments from the Science Education Directorate, National Science Foundation: CAUSE, ISEP, and LOCI: Three-Program Approach to College-Level Science Improvement. II. Patterns and Problems.

    Science.gov (United States)

    Erickson, Judith B.; And Others

    1980-01-01

    Discusses patterns resulting from the monitor of science education proposals which may reflect problems or differing perceptions of NSF. Discusses these areas: proposal submissions from two-year institutions and social and behavioral scientists, trends in project content at the academic-industrial interface and in computer technology, and…

  18. Prospective Turkish Elementary Science Teachers' Knowledge Level about the Greenhouse Effect and Their Views on Environmental Education in University

    Science.gov (United States)

    Kisoglu, Mustafa; Gürbüz, Hasan; Erkol, Mehmet; Akar, Muhammed Said; Akilli, Mustafa

    2010-01-01

    The fundamental factor of environmental education is teachers who are well-informed about environmental issues. This research aimed to determine prospective Turkish elementary science teachers' knowledge level about causes, consequences and reducing of the greenhouse effect and to investigate the effect of gender, information source and membership…

  19. The Materials Used and the Pupils Involved in Environmental Studies and Environmental Science at GCE 'O' and 'A' Level.

    Science.gov (United States)

    Gayford, Christopher

    1984-01-01

    Discusses types of students and materials and resources used in O- and A-level environmental studies and environmental science courses. Indicates that these subjects are very susceptable to the attitudes of teachers (as shown by their willingness to produce satisfactory materials) and by the motivation of students. (JN)

  20. Should applicants to Nottingham University Medical School study a non-science A-level? A cohort study.

    Science.gov (United States)

    Yates, Janet; Smith, Jennifer; James, David; Ferguson, Eamonn

    2009-01-21

    It has been suggested that studying non-science subjects at A-level should be compulsory for medical students. Our admissions criteria specify only Biology, Chemistry and one or more additional subjects. This study aimed to determine whether studying a non-science subject for A-level is an independent predictor of achievement on the undergraduate medical course. The subjects of this retrospective cohort study were 164 students from one entry-year group (October 2000), who progressed normally on the 5-year undergraduate medical course at Nottingham. Pre-admission academic and socio-demographic data and undergraduate course marks were obtained. T-test and hierarchical multiple linear regression analyses were undertaken to identify independent predictors of five course outcomes at different stages throughout the course. There was no evidence that the choice of science or non-science as the third or fourth A-level subject had any influence on course performance. Demographic variables (age group, sex, and fee status) had some predictive value but ethnicity did not. Pre-clinical course performance was the strongest predictor in the clinical phases (pre-clinical Themes A&B (knowledge) predicted Clinical Knowledge, p A-level requirements should specify the choice of third or fourth subject.

  1. Strong compensation hinders the p-type doping of ZnO: a glance over surface defect levels

    Science.gov (United States)

    Huang, B.

    2016-07-01

    We propose a surface doping model of ZnO to elucidate the p-type doping and compensations in ZnO nanomaterials. With an N-dopant, the effects of N on the ZnO surface demonstrate a relatively shallow acceptor level in the band gap. As the dimension of the ZnO materials decreases, the quantum confinement effects will increase and render the charge transfer on surface to influence the shifting of Fermi level, by evidence of transition level changes of the N-dopant. We report that this can overwhelm the intrinsic p-type conductivity and transport of the ZnO bulk system. This may provide a possible route of using surface doping to modify the electronic transport and conductivity of ZnO nanomaterials.

  2. Thirty Years of Social Science Research on High-Level Nuclear Waste: Achievements and Future Challenges

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, Barry D. (Dept. of Social Sciences, Michigan Technological Univ., Houghton (United States)), e-mail: bdsolomo@mtu.edu; Andren, Mats; Strandberg, Urban (Center for Public Sector Research, Univ. of Goeteborg, Goeteborg (Sweden))

    2010-09-15

    Research on high-level nuclear waste management has focused on technical and scientific issues since the U.S. National Academy of Sciences first studied the problem in the mid 1950s and recommended long-term disposal in deep salt formations. In this review, we trace the development of the problem's definition and its associated research since socioeconomic, political and policy issues were first given consideration and nuclear waste management became recognized as more than a technical issue. Three time periods are identified. First, from the mid 1970s to early 1980s, initial research explored institutional dimensions of nuclear waste, including ethics. The second period began in the early 1980s with a concerted effort to solve the problem and site nuclear waste repositories, and ended in the mid 1990s with minimal progress in the U.S. and general stalemate in Asia and Europe (with the notable exception of Sweden). This phase accelerated research on risk perception and stigma of nuclear waste, and elevated a focus on public trust. Great attention was given to repository siting conflicts, while minimal attention was placed on ethics, equity, political systems, and public participation. The last period, since the mid 1990s, has been characterized by continuing political stalemate and increased attention to public participation, political systems and international solutions. Questions of ethics have been given renewed attention, while research on risk perceptions and siting conflicts continues. We frame these periods in a broader context of the shifting role of applied social scientists. The paper concludes with a general discussion of this research area and prospects for future research

  3. Thirty Years of Social Science Research on High-Level Nuclear Waste: Achievements and Future Challenges

    International Nuclear Information System (INIS)

    Solomon, Barry D.; Andren, Mats; Strandberg, Urban

    2010-09-01

    Research on high-level nuclear waste management has focused on technical and scientific issues since the U.S. National Academy of Sciences first studied the problem in the mid 1950s and recommended long-term disposal in deep salt formations. In this review, we trace the development of the problem's definition and its associated research since socioeconomic, political and policy issues were first given consideration and nuclear waste management became recognized as more than a technical issue. Three time periods are identified. First, from the mid 1970s to early 1980s, initial research explored institutional dimensions of nuclear waste, including ethics. The second period began in the early 1980s with a concerted effort to solve the problem and site nuclear waste repositories, and ended in the mid 1990s with minimal progress in the U.S. and general stalemate in Asia and Europe (with the notable exception of Sweden). This phase accelerated research on risk perception and stigma of nuclear waste, and elevated a focus on public trust. Great attention was given to repository siting conflicts, while minimal attention was placed on ethics, equity, political systems, and public participation. The last period, since the mid 1990s, has been characterized by continuing political stalemate and increased attention to public participation, political systems and international solutions. Questions of ethics have been given renewed attention, while research on risk perceptions and siting conflicts continues. We frame these periods in a broader context of the shifting role of applied social scientists. The paper concludes with a general discussion of this research area and prospects for future research

  4. Developing partnerships for implementing continental-scale citizen science programs at the local-level

    Science.gov (United States)

    Newman, S. J.; Henderson, S.; Ward, D.

    2012-12-01

    Project BudBurst is a citizen science project focused on monitoring plant phenology that resides at the National Ecological Observatory Network (NEON, Inc). A central question for Project BudBurst and other national outreach programs is: what are the most effective means of engaging and connecting with diverse communities throughout the country? How can continental scale programs like NEON's Project BudBurst engage audiences in such a way as to be relevant at both the local and continental scales? Staff with Project BudBurst pursued partnerships with several continental scale organizations: the National Wildlife Refuge System, the National Park Service, and botanic gardens to address these questions. The distributed nature of wildlife refuges, national parks, and botanic gardens around the country provided the opportunity to connect with participants locally while working with leadership at multiple scales. Project BudBurst staff talked with hundreds of staff and volunteers prior to setting a goal of obtaining and developing resources for several Refuge Partners, a pilot National Park partner, and an existing botanic garden partner during 2011. We were especially interested in learning best practices for future partnerships. The partnership efforts resulted in resource development for 12 Refuge partners, a pilot National Park partner, and 2 botanic garden partners. Early on, the importance of working with national level leaders to develop ownership of the partner program and input about resource needs became apparent. Once a framework for the partnership program was laid out, it became critical to work closely with staff and volunteers on the ground to ensure needs were met. In 2012 we began to develop an online assessment to allow our current and potential partners to provide feedback about whether or not the partnership program was meeting their needs and how the program could be improved. As the year progressed, the timeline for resource development became more

  5. Investigation of siting parameters for near surface disposal of low-level nuclear waste. Final report

    International Nuclear Information System (INIS)

    Schell, W.R.; Sanchez, A.L.; Thomas, E.D.

    1985-01-01

    A study was initiated in April 1984 to evaluate actual problems associated with and to recommend improvements for near surface disposal of low-level radioactive wastes in the State of Pennsylvania and the humid Northeast. The results of field measurements showed some vertical transport of 137 Cs and other fallout radionuclides in 210 Pb dated peat cores from the unsaturated zone. Under the natural acid rain conditions (pH 4.0), the most mobile radionuclide, 137 Cs, gave diffusion coefficients of 10 -7 to 10 -9 cm 2 /sec in the different organic rich soils. Both the upward and downward migration of radionuclides resulted from the hydrological cycle of evapotranspiration and precipitation which gave diffusive mixing of mobile radionuclides. The distribution coefficient, K/sub d/ values, for several radionuclides in the organic rich soils were found to be equal to or greater than those measured previously for inorganic clay and sediment matrices. To insure that radionuclides do not enter water supplies in the humid Northeast where pH 4.0 rain is encountered, a peat liner should be considered in the multibarrier design of repositories. 32 refs., 16 figs., 8 tabs

  6. Ocean Surface Topography Mission (OSTM) /Jason-2: Level-2 Geophysical Data Records (GDR) (NODC Accession 0043269)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — OSTM/JASON-2 is a follow-on mission continuing the TOPEX/Poseidon and Jason-1, and is designed to ensure continuity of high quality measurements for ocean science...

  7. Master's Level Graduate Training in Medical Physics at the University of Colorado Health Sciences Center.

    Science.gov (United States)

    Ibbott, Geoffrey S.; Hendee, William R.

    1980-01-01

    Describes the master's degree program in medical physics developed at the University of Colorado Health Sciences Center. Required courses for the program, and requirements for admission are included in the appendices. (HM)

  8. Occurrence and levels of polybrominated diphenyl ethers in surface sediments from the Yellow River Estuary, China

    International Nuclear Information System (INIS)

    Yuan, Zijiao; Liu, Guijian; Lam, Michael Hon Wah; Liu, Houqi; Da, Chunnian

    2016-01-01

    A total of 21 surface sediments collected from the Yellow River Estuary, China were analyzed for 40 kinds of polybrominated diphenyl ethers (PBDEs) using gas chromatography-mass spectrometry (GC–MS). Their levels, spatial distribution, congener profiles and possible sources were investigated. Only ten congeners were detected in the sediments. The total concentrations of the lower brominated BDEs (∑PBDEs_l_o_w_, PBDEs excluding BDE 209) and BDE 209 ranged from 0.482 ng/g to 1.07 ng/g and 1.16–5.40 ng/g, with an average value of 0.690 and 2.79 ng/g, respectively, which were both at the low end of the global contamination level. The congener profiles were dominated by BDE 209, with the average value accounting for 79.2% of the total PBDEs in the sediment samples. Among the nine lower brominated BDE congeners, BDE 47, 99 and 183 had high abundances. Although the commercial Penta/Octa-BDE products have been banned in most countries, the residual commercial Penta/Octa/Deca-BDE products and the debromination of highly brominated BDE compounds such as BDE 209 were still found to be the possible sources for the trace level of PBDEs in the present study area. In spite of the gradual removal of the commercial PBDEs in the world, the present research results further suggested that scientific attention should not be reduced on the issue of environmental contamination caused by these outdated chemical compounds. - Highlights: • This is the first study concentrating specifically on PBDEs in the study area. • The commercial Penta/Octa/Deca-BDE products were the possible sources. • The debromination of highly brominated PBDEs were also found to be the sources. • Scientific attention should not be reduced on these outdated chemical compounds. - The commercial Penta/Octa/Deca-BDE products and the debromination of highly brominated BDE compounds were found to be the possible sources.

  9. Science and engineering of nanodiamond particle surfaces for biological applications (Review).

    Science.gov (United States)

    Shenderova, Olga A; McGuire, Gary E

    2015-09-05

    Diamond has outstanding bulk properties such as super hardness, chemical inertness, biocompatibility, luminescence, to name just a few. In the nanoworld, in order to exploit these outstanding bulk properties, the surfaces of nanodiamond (ND) particles must be accordingly engineered for specific applications. Modification of functional groups on the ND's surface and the corresponding electrostatic properties determine their colloidal stability in solvents, formation of photonic crystals, controlled adsorption and release of cargo molecules, conjugation with biomolecules and polymers, and cellular uptake. The optical activity of the luminescent color centers in NDs depends on their proximity to the ND's surface and surface termination. In order to engineer the ND surface, a fundamental understanding of the specific structural features and sp(3)-sp(2) phase transformations on the surface of ND particles is required. In the case of ND particles produced by detonation of carbon containing explosives (detonation ND), it should also be taken into account that its structure depends on the synthesis parameters and subsequent processing. Thus, for development of a strategy of surface modification of detonation ND, it is imperative to know details of its production. In this review, the authors discuss ND particles structure, strategies for surface modification, electrokinetic properties of NDs in suspensions, and conclude with a brief overview of the relevant bioapplications.

  10. Surface enhanced Raman spectroscopy: A review of recent applications in forensic science

    Science.gov (United States)

    Fikiet, Marisia A.; Khandasammy, Shelby R.; Mistek, Ewelina; Ahmed, Yasmine; Halámková, Lenka; Bueno, Justin; Lednev, Igor K.

    2018-05-01

    Surface enhanced Raman spectroscopy has many advantages over its parent technique of Raman spectroscopy. Some of these advantages such as increased sensitivity and selectivity and therefore the possibility of small sample sizes and detection of small concentrations are invaluable in the field of forensics. A variety of new SERS surfaces and novel approaches are presented here on a wide range of forensically relevant topics.

  11. Investigation of Anti-Relaxation Coatings for Alkali-Metal Vapor Cells using Surface Science Techniques

    Science.gov (United States)

    2011-02-01

    addition to the inside surface of the cells. In order to avoid exposure to air, the cells were broken open inside a glovebag containing an argon ...unsaturated bonds increase the polar- izability of the surface, and effective coatings have long been assumed to require low polarizability to enable

  12. Improvements to the swath-level near-surface atmospheric state parameter retrievals within the NRL Ocean Surface Flux System (NFLUX)

    Science.gov (United States)

    May, J. C.; Rowley, C. D.; Meyer, H.

    2017-12-01

    The Naval Research Laboratory (NRL) Ocean Surface Flux System (NFLUX) is an end-to-end data processing and assimilation system used to provide near-real-time satellite-based surface heat flux fields over the global ocean. The first component of NFLUX produces near-real-time swath-level estimates of surface state parameters and downwelling radiative fluxes. The focus here will be on the satellite swath-level state parameter retrievals, namely surface air temperature, surface specific humidity, and surface scalar wind speed over the ocean. Swath-level state parameter retrievals are produced from satellite sensor data records (SDRs) from four passive microwave sensors onboard 10 platforms: the Special Sensor Microwave Imager/Sounder (SSMIS) sensor onboard the DMSP F16, F17, and F18 platforms; the Advanced Microwave Sounding Unit-A (AMSU-A) sensor onboard the NOAA-15, NOAA-18, NOAA-19, Metop-A, and Metop-B platforms; the Advanced Technology Microwave Sounder (ATMS) sensor onboard the S-NPP platform; and the Advanced Microwave Scannin Radiometer 2 (AMSR2) sensor onboard the GCOM-W1 platform. The satellite SDRs are translated into state parameter estimates using multiple polynomial regression algorithms. The coefficients to the algorithms are obtained using a bootstrapping technique with all available brightness temperature channels for a given sensor, in addition to a SST field. For each retrieved parameter for each sensor-platform combination, unique algorithms are developed for ascending and descending orbits, as well as clear vs cloudy conditions. Each of the sensors produces surface air temperature and surface specific humidity retrievals. The SSMIS and AMSR2 sensors also produce surface scalar wind speed retrievals. Improvement is seen in the SSMIS retrievals when separate algorithms are used for the even and odd scans, with the odd scans performing better than the even scans. Currently, NFLUX treats all SSMIS scans as even scans. Additional improvement in all of

  13. Formation of halo-structures in oxygen isotopes through change of occupancy of levels near Fermi surface

    International Nuclear Information System (INIS)

    Bhattacharya, Rupayan

    2000-01-01

    Recently a new parametrisation of Skyrme interaction has been formulated in order to study the level inversions of A=9 isobars. The role of occupancy of 2s 1/2 level in determining the halo structures of O, N, C, B and Be nuclei was shown. A thorough investigation on the binding energies, rms charge, neutron and matter distribution and occupation probabilities of levels near the Fermi surface has been done in the present work

  14. Spectral Feature Analysis of Minerals and Planetary Surfaces in an Introductory Planetary Science Course

    Science.gov (United States)

    Urban, Michael J.

    2013-01-01

    Using an ALTA II reflectance spectrometer, the USGS digital spectral library, graphs of planetary spectra, and a few mineral hand samples, one can teach how light can be used to study planets and moons. The author created the hands-on, inquiry-based activity for an undergraduate planetary science course consisting of freshman to senior level…

  15. science

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

    David Spurgeon

    Give us the tools: science and technology for development. Ottawa, ...... altered technical rela- tionships among the factors used in the process of production, and the en- .... to ourselves only the rights of audit and periodic substantive review." If a ...... and destroying scarce water reserves, recreational areas and a generally.

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

    Science.gov (United States)

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

    2016-10-15

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

  17. Urbanization increased metal levels in lake surface sediment and catchment topsoil of waterscape parks

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hong-Bo [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Yu, Shen, E-mail: syu@iue.ac.cn [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Li, Gui-Lin [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Liu, Yi; Yu, Guang-Bin [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Deng, Hong [Department of Environmental Sciences, Tiantong National Station of Forest Ecosystem, Key Laboratory of Urbanization and Ecological Restoration, East China Normal University, Shanghai 200062 (China); Wu, Sheng-Chun [State Key Laboratory in Marine Pollution, Biology and Chemistry Department, City University of Hong Kong, Hong Kong (China); Wong, Ming-Hung [Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Hong Kong (China)

    2012-08-15

    Lake surface sediment is mainly derived from topsoil in its catchment. We hypothesized that distribution of anthropogenic metals would be homogenous in lake surface sediment and the lake's catchment topsoil. Anthropogenic metal distributions (cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn)) in fourteen waterscape parks were investigated in surface sediments and catchment topsoils and possible source homogeneity was tested using stable Pb isotopic ratio analysis. The parks were located along an urbanization gradient consisting of suburban (SU), developing urban (DIU), developed urban (DDU), and central urban core (CUC) areas in Shanghai, China. Results indicated that surface lake sediments and catchment topsoils in the CUC parks were highly contaminated by the investigated anthropogenic metals. Total metal contents in surface sediment and topsoil gradually increased along the urbanization gradient from the SU to CUC areas. Generally, the surface sediments had greater total metal contents than their catchment topsoils. These results suggest that urbanization drives the anthropogenic metal enrichment in both surface sediment and its catchment topsoil in the waterscape parks. Soil fine particles (< 63 {mu}m) and surface sediments had similar enrichment ratios of metals, suggesting that surface runoff might act as a carrier for metals transporting from catchment to lake. Stable Pb isotope ratio analysis revealed that the major anthropogenic Pb source in surface sediment was coal combustion as in the catchment topsoil. Urbanization also correlated with chemical fractionation of metals in both surface sediment and catchment topsoil. From the SU to the CUC parks, amounts of labile metal fractions increased while the residual fraction of those metals remained rather constant. In short, urbanization in Shanghai drives anthropogenic metal distribution in environmental matrices and the sources were homogenous. -- Highlights: Black-Right-Pointing-Pointer Obvious

  18. Urbanization increased metal levels in lake surface sediment and catchment topsoil of waterscape parks

    International Nuclear Information System (INIS)

    Li, Hong-Bo; Yu, Shen; Li, Gui-Lin; Liu, Yi; Yu, Guang-Bin; Deng, Hong; Wu, Sheng-Chun; Wong, Ming-Hung

    2012-01-01

    Lake surface sediment is mainly derived from topsoil in its catchment. We hypothesized that distribution of anthropogenic metals would be homogenous in lake surface sediment and the lake's catchment topsoil. Anthropogenic metal distributions (cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn)) in fourteen waterscape parks were investigated in surface sediments and catchment topsoils and possible source homogeneity was tested using stable Pb isotopic ratio analysis. The parks were located along an urbanization gradient consisting of suburban (SU), developing urban (DIU), developed urban (DDU), and central urban core (CUC) areas in Shanghai, China. Results indicated that surface lake sediments and catchment topsoils in the CUC parks were highly contaminated by the investigated anthropogenic metals. Total metal contents in surface sediment and topsoil gradually increased along the urbanization gradient from the SU to CUC areas. Generally, the surface sediments had greater total metal contents than their catchment topsoils. These results suggest that urbanization drives the anthropogenic metal enrichment in both surface sediment and its catchment topsoil in the waterscape parks. Soil fine particles (< 63 μm) and surface sediments had similar enrichment ratios of metals, suggesting that surface runoff might act as a carrier for metals transporting from catchment to lake. Stable Pb isotope ratio analysis revealed that the major anthropogenic Pb source in surface sediment was coal combustion as in the catchment topsoil. Urbanization also correlated with chemical fractionation of metals in both surface sediment and catchment topsoil. From the SU to the CUC parks, amounts of labile metal fractions increased while the residual fraction of those metals remained rather constant. In short, urbanization in Shanghai drives anthropogenic metal distribution in environmental matrices and the sources were homogenous. -- Highlights: ► Obvious urbanization effect on metal

  19. One-level modeling for diagnosing surface winds over complex terrain. II - Applicability to short-range forecasting

    Science.gov (United States)

    Alpert, P.; Getenio, B.; Zak-Rosenthal, R.

    1988-01-01

    The Alpert and Getenio (1988) modification of the Mass and Dempsey (1985) one-level sigma-surface model was used to study four synoptic events that included two winter cases (a Cyprus low and a Siberian high) and two summer cases. Results of statistical verification showed that the model is not only capable of diagnosing many details of surface mesoscale flow, but might also be useful for various applications which require operative short-range prediction of the diurnal changes of high-resolution surface flow over complex terrain, for example, in locating wildland fires, determining the dispersion of air pollutants, and predicting changes in wind energy or of surface wind for low-level air flights.

  20. Radionuclide transport modelling for a buried near surface low level radioactive waste

    International Nuclear Information System (INIS)

    Terzi, R.

    2004-01-01

    The disposal of radioactive waste, which is the last step of any radioactive waste management policy, has not yet been developed in Turkey. The existing legislation states only the discharge limits for the radioactive wastes to be discharged to the environment. The objective of this modelling study is to assist in safety assessment and selecting disposal site for gradually increasing non-nuclear radioactive wastes. This mathematical model has been developed for the environmental radiological assessment of near surface disposal sites for the low and intermediate level radioactive wastes. The model comprised of three main components: source term, geosphere transport and radiological assessment. Radiation dose for the babies (1 years age) and adults (≥17 years age) have been computed for the radionuclides Cesium 137 (Cs-137) and Strontium 90 (Sr-90), having the activity of 1.10 12 Becquerel(Bq), in radioactive waste through transport of radionuclide in liquid phase with the various pathways. The model consisted of first order ordinary differential equations was coded as a TCODE file in MATLAB program. The radiation dose to man for the realist case and low probability case have been calculated by using Runge-Kutta solution method in MATLAB programme for radionuclide transport from repository to soil layer and then to the ground water(saturated zone) through drinking water directly and consuming agricultural and animal products pathways in one year period. Also, the fatal cancer risk assessment has been made by taking into account the annual dose received by people. Various dose values for both radionuclides have been found which depended on distribution coefficient, retardation factor and dose conversion factors. The most important critical parameters on radiological safety assessment are the distribution coefficient in soil layer, seepage velocity in unsaturated zone and thickness of the unsaturated zone (soil zone). The highest radiation dose and average dose to

  1. Process-oriented guided inquiry learning strategy enhances students' higher level thinking skills in a pharmaceutical sciences course.

    Science.gov (United States)

    Soltis, Robert; Verlinden, Nathan; Kruger, Nicholas; Carroll, Ailey; Trumbo, Tiffany

    2015-02-17

    To determine if the process-oriented guided inquiry learning (POGIL) teaching strategy improves student performance and engages higher-level thinking skills of first-year pharmacy students in an Introduction to Pharmaceutical Sciences course. Overall examination scores and scores on questions categorized as requiring either higher-level or lower-level thinking skills were compared in the same course taught over 3 years using traditional lecture methods vs the POGIL strategy. Student perceptions of the latter teaching strategy were also evaluated. Overall mean examination scores increased significantly when POGIL was implemented. Performance on questions requiring higher-level thinking skills was significantly higher, whereas performance on questions requiring lower-level thinking skills was unchanged when the POGIL strategy was used. Student feedback on use of this teaching strategy was positive. The use of the POGIL strategy increased student overall performance on examinations, improved higher-level thinking skills, and provided an interactive class setting.

  2. Village-level supply reliability of surface water irrigation in rural China: effects of climate change

    Science.gov (United States)

    Li, Yanrong; Wang, Jinxia

    2018-06-01

    Surface water, as the largest part of water resources, plays an important role on China's agricultural production and food security. And surface water is vulnerable to climate change. This paper aims to examine the status of the supply reliability of surface water irrigation, and discusses how it is affected by climate change in rural China. The field data we used in this study was collected from a nine-province field survey during 2012 and 2013. Climate data are offered by China's National Meteorological Information Center which contains temperature and precipitation in the past 30 years. A Tobit model (or censored regression model) was used to estimate the influence of climate change on supply reliability of surface water irrigation. Descriptive results showed that, surface water supply reliability was 74 % in the past 3 years. Econometric results revealed that climate variables significantly influenced the supply reliability of surface water irrigation. Specifically, temperature is negatively related with the supply reliability of surface water irrigation; but precipitation positively influences the supply reliability of surface water irrigation. Besides, climate influence differs by seasons. In a word, this paper improves our understanding of the impact of climate change on agriculture irrigation and water supply reliability in the micro scale, and provides a scientific basis for relevant policy making.

  3. Mathematical estimation of the level of microbial contamination on spacecraft surfaces by volumetric air sampling

    Science.gov (United States)

    Oxborrow, G. S.; Roark, A. L.; Fields, N. D.; Puleo, J. R.

    1974-01-01

    Microbiological sampling methods presently used for enumeration of microorganisms on spacecraft surfaces require contact with easily damaged components. Estimation of viable particles on surfaces using air sampling methods in conjunction with a mathematical model would be desirable. Parameters necessary for the mathematical model are the effect of angled surfaces on viable particle collection and the number of viable cells per viable particle. Deposition of viable particles on angled surfaces closely followed a cosine function, and the number of viable cells per viable particle was consistent with a Poisson distribution. Other parameters considered by the mathematical model included deposition rate and fractional removal per unit time. A close nonlinear correlation between volumetric air sampling and airborne fallout on surfaces was established with all fallout data points falling within the 95% confidence limits as determined by the mathematical model.

  4. Journal of Earth System Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 120; Issue 4 ... DEM; cell size; sink; fractal dimension; entropy; semivariogram. ... These methods were applied to determine the level artifacts (interpolation error) in DEM surface as ...

  5. Measuring Changes in Interest in Science and Technology at the College Level in Response to Two Instructional Interventions

    Science.gov (United States)

    Romine, William L.; Sadler, Troy D.

    2016-06-01

    Improving interest in science, technology, engineering, and mathematics (STEM) is crucial to widening participation and success in STEM studies at the college level. To understand how classroom and extracurricular interventions affect interest, it is necessary to have appropriate measurement tools. We describe the adaptation and revalidation of a previously existing multidimensional instrument to the end of measuring interest in environmental science and technology in college nonscience majors. We demonstrate the revised instrument's ability to detect change in this group over an 8-week time period. While collection of demographic information was not part of the study design, participating students were similar in that they hailed from three environmental science nonmajor classes sharing a common syllabus and instructional delivery method. Change in interest was measured in response to two types of scientific literature-based learning approaches: a scientific practice approach and a traditional, quiz-driven approach. We found that both approaches led to moderate gains in interest in learning environmental science and careers in environmental science across an 8-week time period. Interest in using technology for learning increased among students using the scientific practice approach; in contrast, the same measure decreased among students using the reading/quiz approach. This result invites the possibility that interest in using technology as a learning tool may relate to technological literacy, which must be taught explicitly in the context of authentic inquiry experiences.

  6. Core journals in library and information science: measuring the level of specialization over time

    DEFF Research Database (Denmark)

    Nicolaisen, J.; Frandsen, T. F.

    2013-01-01

    years. The method is applied to a selection of core journals in library and information science (1990-2012). The reference lists of each journal are compared year by year, and the percentage of re-citations is calculated by dividing the number of re-citations with the total number of citations each year......Introduction. Specialization in science is a process that occurs over time. The present paper presents a bibliometric method for measuring the degree of specialization over time. Methods. The method is based on bibliographic coupling, and counts the percentage of recitations given in subsequent...

  7. Content, format, gender and grade level differences in elementary students' ability to read science materials as measured by the cloze procedure

    Science.gov (United States)

    Williams, Richard L.; Yore, Larry D.

    Present instructional trends in science indicate a need to reexamine a traditional concern in science education: the readability of science textbooks. An area of reading research not well documented is the effect of color, visuals, and page layout on readability of science materials. Using the cloze readability method, the present study explored the relationships between page format, grade level, sex, content, and elementary school students ability to read science material. Significant relationships were found between cloze scores and both grade level and content, and there was a significant interaction effect between grade and sex in favor of older males. No significant relationships could be attributed to page format and sex. In the area of science content, biological materials were most difficult in terms of readability followed by earth science and physical science. Grade level data indicated that grade five materials were more difficult for that level than either grade four or grade six materials were for students at each respective level. In eight of nine cases, the science text materials would be classified at or near the frustration level of readability. The implications for textbook writers and publishers are that science reading materials need to be produced with greater attention to readability and known design principles regarding visual supplements. The implication for teachers is that students need direct instruction in using visual materials to increase their learning from text material. Present visual materials appear to neither help nor hinder the student to gain information from text material.

  8. Core Principles and Test Item Development for Advanced High School and Introductory University Level Food Science

    Science.gov (United States)

    Laing-Kean, Claudine A. M.

    2010-01-01

    Programs supported by the Carl D. Perkins Act of 2006 are required to operate under the state or national content standards, and are expected to carry out evaluation procedures that address accountability. The Indiana high school course, "Advanced Life Science: Foods" ("ALS: Foods") operates under the auspices of the Perkins…

  9. Department-Level Representations: A New Approach to the Study of Science Teacher Cognition

    Science.gov (United States)

    Hutner, Todd L.; Markman, Arthur B.

    2016-01-01

    Research on science teacher cognition is important as findings from this research can be used to improve teacher training, leading to improved classroom practice. Previous research has often relied on two underlying assumptions: Cognition is an individual process, and these processes are detailed and introspective. In this paper, we put forth a…

  10. Interdisciplinarity at the journal and specialty level: the changing knowledge bases of the journal Cognitive Science

    NARCIS (Netherlands)

    Leydesdorff, L.; Goldstone, R.L.

    2014-01-01

    Using the referencing patterns in articles in Cognitive Science over three decades, we analyze the knowledge base of this literature in terms of its changing disciplinary composition. Three periods are distinguished: (A) construction of the interdisciplinary space in the 1980s, (B) development of an

  11. A Diagnosis of the Levels of Information Literacy Competency among Social Sciences Undergraduates

    Science.gov (United States)

    Pinto, María; Fernández-Pascual, Rosaura

    2017-01-01

    Restricted to five Spanish public universities, this paper examines knowledge about information literacy competencies--that is, the objective dimension--among a population of social sciences students, as well as two subjective dimensions: students' belief in the importance of information literacy, hereafter called "belief-in-importance",…

  12. Comparing Panelists' Understanding of Standard Setting across Multiple Levels of an Alternate Science Assessment

    Science.gov (United States)

    Hansen, Mary A.; Lyon, Steven R.; Heh, Peter; Zigmond, Naomi

    2013-01-01

    Large-scale assessment programs, including alternate assessments based on alternate achievement standards (AA-AAS), must provide evidence of technical quality and validity. This study provides information about the technical quality of one AA-AAS by evaluating the standard setting for the science component. The assessment was designed to have…

  13. Exploring the Self-Reported ICT Skill Levels of Undergraduate Science Students

    Science.gov (United States)

    Heerwegh, Dirk; De Wit, Kurt; Verhoeven, Jef C.

    2016-01-01

    Computers have taken an important place in the training of science students and in the professional life of scientists. It is often taken for granted that most students have mastered basic Information and Communication Technologies (ICT) skills; however, it has been shown that not all students are equally proficient in this regard. Starting from…

  14. Ethers on Si(001): A Prime Example for the Common Ground between Surface Science and Molecular Organic Chemistry.

    Science.gov (United States)

    Pecher, Lisa; Laref, Slimane; Raupach, Marc; Tonner, Ralf

    2017-11-20

    By using computational chemistry it has been shown that the adsorption of ether molecules on Si(001) under ultrahigh vacuum conditions can be understood with classical concepts of organic chemistry. Detailed analysis of the two-step reaction mechanism-1) formation of a dative bond between the ether oxygen atom and a Lewis acidic surface atom and 2) nucleophilic attack of a nearby Lewis basic surface atom-shows that it mirrors acid-catalyzed ether cleavage in solution. The O-Si dative bond is the strongest of its kind, and the reactivity in step 2 defies the Bell-Evans-Polanyi principle. Electron rearrangement during C-O bond cleavage has been visualized with a newly developed method for analyzing bonding, which shows that the mechanism of nucleophilic substitutions on semiconductor surfaces is identical to molecular S N 2 reactions. Our findings illustrate how surface science and molecular chemistry can mutually benefit from each other and unexpected insight can be gained. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. [Progress in the application of laser ablation ICP-MS to surface microanalysis in material science].

    Science.gov (United States)

    Zhang, Yong; Jia, Yun-hai; Chen, Ji-wen; Shen, Xue-jing; Liu, Ying; Zhao, Leiz; Li, Dong-ling; Hang, Peng-cheng; Zhao, Zhen; Fan, Wan-lun; Wang, Hai-zhou

    2014-08-01

    In the present paper, apparatus and theory of surface analysis is introduced, and the progress in the application of laser ablation ICP-MS to microanalysis in ferrous, nonferrous and semiconductor field is reviewed in detail. Compared with traditional surface analytical tools, such as SEM/EDS (scanning electron microscopy/energy dispersive spectrum), EPMA (electron probe microanalysis analysis), AES (auger energy spectrum), etc. the advantage is little or no sample preparation, adjustable spatial resolution according to analytical demand, multi-element analysis and high sensitivity. It is now a powerful complementary method to traditional surface analytical tool. With the development of LA-ICP-MS technology maturing, more and more analytical workers will use this powerful tool in the future, and LA-ICP-MS will be a super star in elemental analysis field just like LIBS (Laser-induced breakdown spectroscopy).

  16. Surface science analysis of GaAs photocathodes following sustained electron beam delivery

    Directory of Open Access Journals (Sweden)

    V. Shutthanandan

    2012-06-01

    Full Text Available Degradation of the photocathode materials employed in photoinjectors represents a challenge for sustained operation of nuclear physics accelerators and high power free electron lasers (FEL. Photocathode quantum efficiency degradation is due to residual gases in the electron source vacuum system being ionized and accelerated back to the photocathode. These investigations are a first attempt to characterize the nature of the photocathode degradation, and employ multiple surface and bulk analysis techniques to investigate damage mechanisms including sputtering of the Cs-oxidant surface monolayer, other surface chemistry effects, and ion implantation. Surface and bulk analysis studies were conducted on two GaAs photocathodes, which were removed from the JLab FEL DC photoemission gun after delivering electron beam, and two control samples. The analysis techniques include helium ion microscopy, Rutherford backscattering spectrometry (RBS, atomic force microscopy, and secondary ion mass spectrometry (SIMS. In addition, two high-polarization strained superlattice GaAs photocathode samples, one removed from the continuous electron beam accelerator facility (CEBAF photoinjector and one unused, were also analyzed using transmission electron microscopy (TEM and SIMS. It was found that heat cleaning the FEL GaAs wafer introduces surface roughness, which seems to be reduced by prolonged use. The bulk GaAs samples retained a fairly well organized crystalline structure after delivering beam but show evidence of Cs depletion on the surface. Within the precision of the SIMS and RBS measurements, the data showed no indication of hydrogen implantation or lattice damage from ion back bombardment in the bulk GaAs wafers. In contrast, SIMS and TEM measurements of the strained superlattice photocathode show clear crystal damage in the wafer from ion back bombardment.

  17. Lunar and planetary surface conditions advances in space science and technology

    CERN Document Server

    Weil, Nicholas A

    1965-01-01

    Lunar and Planetary Surface Conditions considers the inferential knowledge concerning the surfaces of the Moon and the planetary companions in the Solar System. The information presented in this four-chapter book is based on remote observations and measurements from the vantage point of Earth and on the results obtained from accelerated space program of the United States and U.S.S.R. Chapter 1 presents the prevalent hypotheses on the origin and age of the Solar System, followed by a brief description of the methods and feasibility of information acquisition concerning lunar and planetary data,

  18. Derivation of Waste Acceptance Criteria for Low and Intermediate Level Waste in Surface Disposal Facility

    International Nuclear Information System (INIS)

    Gagner, L.; Voinis, S.

    2000-01-01

    In France, low- and intermediate-level radioactive wastes are disposed in a near-surface facility, at Centre de l'Aube disposal facility. This facility, which was commissioned in 1992, has a disposal capacity of one million cubic meters, and will be operated up to about 2050. It took over the job from Centre de la Manche, which was commissioned in 1969 and shut down in 1994, after having received about 520,000 cubic meters of wastes. The Centre de l'Aube disposal facility is designed to receive a many types of waste produced by nuclear power plants, reprocessing, decommissioning, as well as by the industry, hospitals and armed forces. The limitation of radioactive transfer to man and the limitation of personnel exposure in all situations considered plausible require limiting the total activity of the waste disposed in the facility as well as the activity of each package. The paper presents how ANDRA has derived the activity-related acceptance criteria, based on the safety analysis. In the French methodology, activity is considered as end-point for deriving the concentration limits per package, whereas it is the starting point for deriving the total activity limits. For the concentration limits (called here LMA) the approach consists of five steps: the determination of radionuclides important for safety with regards to operational and long-term safety, the use of relevant safety scenarios as a tool to derive quantitative limits, the setting of dose constraint per situation associated with scenarios, the setting of contribution factor per radionuclide, and the calculation of concentration activity limits. An exhaustive survey has been performed and has shown that the totality of waste packages which should be delivered by waste generators are acceptable in terms of activity limits in the Centre de l'Aube. Examples of concentration activity limits derived from this methodology are presented. Furthermore those limits have been accepted by the French regulatory body and

  19. Contamination levels of human pharmaceutical compounds in French surface and drinking water.

    Science.gov (United States)

    Mompelat, S; Thomas, O; Le Bot, B

    2011-10-01

    The occurrence of 20 human pharmaceutical compounds and metabolites from 10 representative therapeutic classes was analysed from resource and drinking water in two catchment basins located in north-west France. 98 samples were analysed from 63 stations (surface water and drinking water produced from surface water). Of the 20 human pharmaceutical compounds selected, 16 were quantified in both the surface water and drinking water, with 22% of the values above the limit of quantification for surface water and 14% for drinking water). Psychostimulants, non-steroidal anti-inflammatory drugs, iodinated contrast media and anxiolytic drugs were the main therapeutic classes of human pharmaceutical compounds detected in the surface water and drinking water. The results for surface water were close to results from previous studies in spite of differences in prescription rates of human pharmaceutical compounds in different countries. The removal rate of human pharmaceutical compounds at 11 water treatment units was also determined. Only caffeine proved to be resistant to drinking water treatment processes (with a minimum rate of 5%). Other human pharmaceutical compounds seemed to be removed more efficiently (average elimination rate of over 50%) by adsorption onto activated carbon and oxidation/disinfection with ozone or chlorine (not taking account of the disinfection by-products). These results add to the increasing evidence of the occurrence of human pharmaceutical compounds in drinking water that may represent a threat to human beings exposed to a cocktail of human pharmaceutical compounds and related metabolites and by-products in drinking water.

  20. Prospective Turkish elementary science teachers’ knowledge level about the greenhouse effect and their views on environmental education in university

    OpenAIRE

    Mustafa Kışoğlu; Hasan Gürbüz; Mehmet Erkol; Muhammed Said Akar; Mustafa Akıllı

    2010-01-01

    The fundamental factor of environmental education is teachers who are well-informed about environmental issues. This research aimed to determine prospective Turkish elementary science teachers’ knowledge level about causes, consequences and reducing of the greenhouse effect and to investigate the effect of gender, information source and membership in the environmental foundations on their knowledge. We also aimed to learn their views on environmental education given in universi...

  1. The Next Generation of Scientists: Examining the Experiences of Graduate Students in Network-Level Social-Ecological Science

    Directory of Open Access Journals (Sweden)

    Michele Romolini

    2013-09-01

    Full Text Available By integrating the research and resources of hundreds of scientists from dozens of institutions, network-level science is fast becoming one scientific model of choice to address complex problems. In the pursuit to confront pressing environmental issues such as climate change, many scientists, practitioners, policy makers, and institutions are promoting network-level research that integrates the social and ecological sciences. To understand how this scientific trend is unfolding among rising scientists, we examined how graduate students experienced one such emergent social-ecological research initiative, Integrated Science for Society and Environment, within the large-scale, geographically distributed Long Term Ecological Research (LTER Network. Through workshops, surveys, and interviews, we found that graduate students faced challenges in how they conceptualized and practiced social-ecological research within the LTER Network. We have presented these conceptual challenges at three scales: the individual/project, the LTER site, and the LTER Network. The level of student engagement with and knowledge of the LTER Network was varied, and students faced different institutional, cultural, and logistic barriers to practicing social-ecological research. These types of challenges are unlikely to be unique to LTER graduate students; thus, our findings are relevant to other scientific networks implementing new social-ecological research initiatives.

  2. Electron paramagnetic resonance and dynamic nuclear polarization of char suspensions: surface science and oximetry

    DEFF Research Database (Denmark)

    Clarkson, R B; Odintsov, B M; Ceroke, P J

    1998-01-01

    ; they can be calibrated and used for oximetry. Biological stability and low toxicity make chars good sensors for in vivo measurements. Scalar and dipolar interactions of water protons at the surfaces of chars may be utilized to produce dynamic nuclear polarization (DNP) of the nuclear spin population...

  3. The application of surface science in the solution of aircraft materials problems

    International Nuclear Information System (INIS)

    Arnott, D.R.

    1999-01-01

    Full text: There is now a tendency for both commercial and military aircraft to be maintained and operated for several decades. Indeed some of our front-line defence aircraft have programme withdrawal lives approaching half a century. This places significant demands on the materials used in engines and airframes. The properties and performance of the materials can degrade with time leading to an increase in the importance of repair and maintenance technologies. As most materials problems start at a surface or an interface, it is not surprising that surface sensitive tools are used to resolve many degradation problems. In some cases, the resolution of problems can lead to life-enhancing improvements for the aircraft. This paper will examine some of the practical issues in the use of surface analytical tools for the examination and resolution of practical aircraft problems. Illustrations will be drawn from the application of surface analysis in the areas of corrosion, fracture and adhesive bonding. Copyright (1999) Australian X-ray Analytical Association Inc

  4. Teeth and bones: applications of surface science to dental materials and related biomaterials

    Science.gov (United States)

    Jones, F. H.

    2001-05-01

    Recent years have seen a considerable upsurge in publications concerning the surface structure and chemistry of materials with biological or biomedical applications. Within the body, gas-solid interactions become relatively less significant and solid-liquid or solid-solid interfaces dominate, providing new challenges for the surface scientist. The current paper aims to provide a timely review of the use of surface analysis and modification techniques within the biomaterials field. A broad overview of applications in a number of related areas is given with particular attention focusing on those materials commonly encountered in dentistry and oral or maxillofacial implantology. Several specific issues of current interest are discussed. The interaction between synthetic and natural solids, both in the oral environment and elsewhere in the body is important in terms of adhesion, related stresses and strains and ultimately the longevity of a dental restoration, biomedical implant, or indeed the surrounding tissue. Exposure to body fluids, of course, can also affect stability, leading to the degradation or corrosion of materials within the body. Whilst this could potentially be harmful, e.g., if cytotoxic elements are released, it may alternatively provide a route to the preferential release of beneficial substances. Furthermore, in some cases, the controlled disintegration of a biomaterial is desirable, allowing the removal of an implant, e.g., without the need for further surgery. The presence of cells in the immediate bioenvironment additionally complicates the situation. A considerable amount of current research activity is targeted at the development of coatings or surface treatments to encourage tissue growth. If this is to be achieved by stimulating enhanced cell productivity, determination of the relationship between cell function and surface composition is essential.

  5. Questions of qualification exam for non-destructive testing and materials science - the first level

    International Nuclear Information System (INIS)

    Shaaban, H.I.; Addarwish, J.M.A.

    2013-01-01

    The book contains seven chapters: Questions of qualification for magnetic particles testing method - Questions of qualification for liquids penetrant testing method - Questions of qualification for the visual inspection testing method - Questions of qualification for the ultrasonic testing method - Questions of qualification for the eddy current testing method - Questions of rehabilitation for industrial radiographic testing method - Qualification questions about materials science and manufacturing defects of castings and welding and comparison between non-destructive testing methods.

  6. Levels of use of an elementary school inquiry-based instructional innovation among a selected group of teacher participants in the Delaware Elementary Science Initiative

    Science.gov (United States)

    Bouchelle, Henry Ellsworth Wirt, III

    Science education in Delaware's public elementary and middle schools has experienced much change in recent years as a result of the adoption of state standards and, in particular, the adoption by school districts of the Smithsonian/National Science Resources Council-sponsored inquiry-based instruction modules as part of the "Elementary Science Initiative." As part of this adoption process, each participating elementary teacher and middle school science teacher receives extensive training in the use of several discrete science kits. The trainings include reinforcement and development of content knowledge, in addition to the modeling of and practice with complementary pedagogy. One measure of the effectiveness of the science kit training process (and perhaps the Initiative itself) is the teachers' levels of use of the Initiative. The purpose of this study was to determine the participating teachers' use of the science kit innovation through the use of the Concerns-based Adoption Model Levels of Use Questionnaire. Eight K--5 elementary classroom teachers who had completed at least three science kit trainings participated. The results of this study indicate that on the Overall Level of Use Rating Scale, teachers who had completed training in at least three science kits generally scored at the Routine (IVA) level. All of the teachers, regardless of the wide range in the number of years of experience, had achieved the Mechanical Use level in Overall (III) LoU, and 6 of the 8 participants (75%) were operating at no less than the Refinement (IVA) Overall LoU level.

  7. Exploring How Second Grade Elementary Teachers Translate Their Nature of Science Views into Classroom Practice After a Graduate Level Nature of Science Course

    Science.gov (United States)

    Deniz, Hasan; Adibelli, Elif

    2015-12-01

    The main purpose of this study was to explore the factors mediating the translation of second grade teachers' nature of science (NOS) views into classroom practice after completing a graduate level NOS course. Four second grade in-service elementary teachers comprised the sample of this study. Data were collected from several sources during the course of this study. The primary data sources were (a) assessment of the elementary teachers' NOS views before and after the graduate level NOS course using the Views of Nature of Science Questionnaire Version B (VNOS-B) (Lederman et al., 2002) coupled with interviews, and (b) a classroom observation and videotaped recording of the elementary teachers' best NOS lessons coupled with interview. We identified three distinct but related factors that mediated the translation of NOS views into classroom practice: the teachers' perspectives about the developmental appropriateness of the NOS aspect, the teachers' selection of target NOS aspects, and the relative importance placed by teachers on each NOS aspect.

  8. A method for the experimental determination of surface photoemission core-level shifts for 3d transition metals

    NARCIS (Netherlands)

    Shamsutdinov, N.R.; Sloof, W.G.; Böttger, A.J.

    2005-01-01

    A method is presented to determine the photoelectron surface core-level shift (SCLS) of 3d transition metals using x-ray photoelectron spectroscopy. The experimental difficulties arising from the relatively large broadening of photoemission lines in the 3d transition series can be overcome by the

  9. Student-Life Stress Level and its Related Factors among Medical Students of Hamadan University of Medical Sciences in 2015

    Directory of Open Access Journals (Sweden)

    Roya Nikanjam

    2016-03-01

    Full Text Available Background and Objectives: Student-life stress can lead to various negative consequences such as physical illness, mental disorders or exhaustion. The present study was conducted to evaluate the level of student life stress and its related factors among medical students of Hamadan University of Medical Sciences. Materials and Methods: This cross-sectional study applied multistage random sampling to select 500university students at Hamadan University of Medical Sciences during 2015. The data collection tool used in this study was a self-report questionnaire containing two parts: a section on subjects' demographic details and another section for Student-Life Stress Inventory (SLSI. Data were analyzed in SPSS20-using descriptive and inferential statistics, such as independent t-test, Pearson’s correlation test and one-way ANOVA. Results: This study revealed that %57of the students had moderate levels of stress. The most important stressors included self-impose and pressure, and also the most important reactions to stressors included cognitive appraisal and emotional reactions, respectively. There was a significant association between exam stressors and branch, educational level, and mother's and father's education level (P< 0.05. Conclusions: According to the high level of stress in students and the recognition of demographic factors, effective educational interventions can be conducted to reduce stress.

  10. Monitoring surface water quality using social media in the context of citizen science

    Science.gov (United States)

    Zheng, Hang; Hong, Yang; Long, Di; Jing, Hua

    2017-02-01

    Surface water quality monitoring (SWQM) provides essential information for water environmental protection. However, SWQM is costly and limited in terms of equipment and sites. The global popularity of social media and intelligent mobile devices with GPS and photography functions allows citizens to monitor surface water quality. This study aims to propose a method for SWQM using social media platforms. Specifically, a WeChat-based application platform is built to collect water quality reports from volunteers, which have been proven valuable for water quality monitoring. The methods for data screening and volunteer recruitment are discussed based on the collected reports. The proposed methods provide a framework for collecting water quality data from citizens and offer a primary foundation for big data analysis in future research.

  11. Investigation of the Effect of Water Removal from Wells Surrounding Parishan Lake on Groundwater and Surface Water Levels

    International Nuclear Information System (INIS)

    Shafiei, M.; Raini Sarjaz, M.; Fazloli, R.; Gholami Sefidkouhi, M. A.

    2017-01-01

    In recent decades the human impacts on global warming and, its consequences, climate change, stirred up earth ecosystems balance and has created many problems all over the world. Unauthorized underground water removal, especially in arid and semi-arid regions of Iran, along with recent decade drought occurrences significantly lowered underground and surface water levels. To investigate the impacts of water removal from surrounding wells in Parishan Lake water level, during 1996 to 2009 interval, 8 buffer layers surrounding the lake were mapped in ArcGIS 9.3 environment. Each buffer layer wells and their total annual discharges were determined. Using SPSS 16 software, the regression equations between wells water levels and water discharges were computed. By employing Thiessen function and creating Thiessen network (TIN) around observation wells, decline of groundwater levels was evaluated. Finally regression equations between wells discharges and groundwater level declines were created. The findings showed that there are highly significant correlations (p ≤ 0.01), in all buffer layers, between water levels and wells discharges. Investigation of the observation wells surrounding lake showed that severe groundwater level declines has been started since the beginning of the first decade of the 21st century. Using satellite images in ArcGIS 9.3 environment it was confirmed that lake’s area has been reduced significantly. In conclusion, it is obvious that human interferences on lake’s natural ecosystem by digging unauthorized wells and removing underground water more than annual recharges significantly impacted surface and groundwater levels.

  12. Perceptions of Climate Change, Sea Level Rise, and Possible Consequences Relate Mainly to Self-Valuation of Science Knowledge.

    Science.gov (United States)

    Burger, Joanna; Gochfeld, Michael; Pittfield, Taryn; Jeitner, Christian

    2016-05-01

    This study examines perceptions of climate change and sea level rise in New Jersey residents in 2012 and 2014. Different surveys have shown declines in interest and concern about climate change and sea level rise. Climate change and increasing temperatures have an anthropogenic cause, which relates to energy use, making it important to examine whether people believe that it is occurring. In late 2012 New Jersey experienced Super storm Sandy, one of the worst hurricanes in its history, followed by public discussion and media coverage of stronger more frequent storms due to climate change. Using structured interviews, we tested the null hypotheses that there were no differences in perceptions of 1260 interviewees as a function of year of the survey, age, gender, years of education, and self-evaluation of science knowledge (on a scale of 1 to 5). In 2012 460 of 639 (72%) rated "global warming occurring" as "certain" (#4) or "very certain" (#5) compared with 453 of 621 (73%) in 2014. For "due to human activities" the numbers of "certain" or "very certain" were 71% in 2012, and 67% in 2014 and for sea level rise the numbers were 64% and 70%. There were some inconsistent between-year differences with higher ratings in 2012 for 3 outcomes and higher ratings in 2014 for 5 outcomes. However, for 25 questions relative to climate change, sea level rise, and the personal and ecological effects of sea level rise, self-evaluation of science knowledge, independent of years of education, was the factor that entered 23 of the models, accounting for the most variability in ratings. People who believed they had a "high knowledge" (#4) or "very high knowledge" (#5) of science rated all issues as more important than did those people who rated their own scientific knowledge as average or below average.

  13. Molecular-level removal of proteinaceous contamination from model surfaces and biomedical device materials by air plasma treatment.

    Science.gov (United States)

    Banerjee, K K; Kumar, S; Bremmell, K E; Griesser, H J

    2010-11-01

    Established methods for cleaning and sterilising biomedical devices may achieve removal of bioburden only at the macroscopic level while leaving behind molecular levels of contamination (mainly proteinaceous). This is of particular concern if the residue might contain prions. We investigated at the molecular level the removal of model and real-life proteinaceous contamination from model and practical surfaces by air plasma (ionised air) treatment. The surface-sensitive technique of X-ray photoelectron spectroscopy (XPS) was used to assess the removal of proteinaceous contamination, with the nitrogen (N1s) photoelectron signal as its marker. Model proteinaceous contamination (bovine serum albumin) adsorbed on to a model surface (silicon wafer) and the residual proteinaceous contamination resulting from incubating surgical stainless steel (a practical biomaterial) in whole human blood exhibited strong N1s signals [16.8 and 18.5 atomic percent (at.%), respectively] after thorough washing. After 5min air plasma treatment, XPS detected no nitrogen on the sample surfaces, indicating complete removal of proteinaceous contamination, down to the estimated XPS detection limit 10ng/cm(2). Applying the same plasma treatment, the 7.7at.% nitrogen observed on a clinically cleaned dental bur was reduced to a level reflective of new, as-received burs. Contact angle measurements and atomic force microscopy also indicated complete molecular-level removal of the proteinaceous contamination upon air plasma treatment. This study demonstrates the effectiveness of air plasma treatment for removing proteinaceous contamination from both model and practical surfaces and offers a method for ensuring that no molecular residual contamination such as prions is transferred upon re-use of surgical and dental instruments. Crown Copyright © 2010. Published by Elsevier Ltd. All rights reserved.

  14. Microplastic distribution in global marine surface waters: results of an extensive citizen science study

    Science.gov (United States)

    Barrows, A.; Petersen, C.

    2017-12-01

    Plastic is a major pollutant throughout the world. The majority of the 322 million tons produced annually is used for single-use packaging. What makes plastic an attractive packaging material: cheap, light-weight and durable are also the features that help make it a common and persistent pollutant. There is a growing body of research on microplastic, particles less than 5 mm in size. Microfibers are the most common microplastic in the marine environment. Global estimates of marine microplastic surface concentrations are based on relatively small sample sizes when compared to the vast geographic scale of the ocean. Microplastic residence time and movement along the coast and sea surface outside of the gyres is still not well researched. This five-year project utilized global citizen scientists to collect 1,628 1-liter surface grab samples in every major ocean. The Artic and Southern oceans contained highest average of particles per liter of surface water. Open ocean samples (further than 12 nm from land, n = 686) contained a higher particle average (17 pieces L-1) than coastal samples (n = 723) 6 pieces L-1. Particles were predominantly 100 µm- 1.5 mm in length (77%), smaller than what has been captured in the majority of surface studies. Utilization of citizen scientists to collect data both in fairly accessible regions of the world as well as from areas hard to reach and therefore under sampled, provides us with a wider perspective of global microplastics occurrence. Our findings confirm global microplastic accumulation zone model predictions. The open ocean and poles have sequestered and trapped plastic for over half a century, and show that not only plastics, but anthropogenic fibers are polluting the environment. Continuing to fill knowledge gaps on microplastic shape, size and color in remote ocean areas will drive more accurate oceanographic models of plastic accumulation zones. Incorporation of smaller-sized particles in these models, which has previously

  15. Water level observations from Unmanned Aerial Vehicles for improving estimates of surface water-groundwater interaction

    DEFF Research Database (Denmark)

    Bandini, Filippo; Butts, Michael; Vammen Jacobsen, Torsten

    2017-01-01

    spatial resolution; ii) spatially continuous profiles along or across the water body; iii) flexible timing of sampling. A semi-synthetic study was conducted to analyse the value of the new UAV-borne datatype for improving hydrological models, in particular estimates of GW (Groundwater)- SW (Surface Water...

  16. Rover exploration on the lunar surface; a science proposal for SELENE-B mission

    Science.gov (United States)

    Sasaki, S.; Kubota, T.; Akiyama, H.; Hirata, N.; Kunii, Y.; Matsumoto, K.; Okada, T.; Otake, M.; Saiki, K.; Sugihara, T.

    LUNARSURFACE:ASCIENCES. Sasaki (1), T. Kubota (2) , H. Akiyama (1) , N. Hirata (3), Y. Kunii (4), K. Matsumoto (5), T. Okada (2), M. Otake (3), K. Saiki (6), T. Sugihara (3) (1) Department of Earth and Planetary Science, Univ. Tokyo, (2) Institute of Space and Astronautical Sciences, (3) National Space Development Agency of Japan, (4) Department of Electrical and Electronic Engineering, Chuo Univ., (5) National Aerospace Laboratory of Japan, (6) Research Institute of Materials and Resources, Akita Univ. sho@eps.s.u -tokyo.ac.jp/Fax:+81-3-5841-4569 A new lunar landing mission (SELENE-B) is now in consideration in Japan. Scientific investigation plans using a rover are proposed. To clarify the origin and evolution of the moon, the early crustal formation and later mare volcanic processes are still unveiled. We proposed two geological investigation plans: exploration of a crater central peak to discover subsurface materials and exploration of dome-cone structures on young mare region. We propose multi-band macro/micro camera using AOTF, X-ray spectrometer/diffractometer and gamma ray spectrometer. Since observation of rock fragments in brecciaed rocks is necessary, the rover should have cutting or scraping mechanism of rocks. In our current scenario, landing should be performed about 500m from the main target (foot of a crater central peak or a cone/dome). After the spectral survey by multi-band camera on the lander, the rover should be deployed for geological investigation. The rover should make a short (a few tens meter) round trip at first, then it should perform traverse observation toward the main target. Some technological investigations on SELENE-B project will be also presented.

  17. Comparing levels of school performance to science teachers' reports on knowledge/skills, instructional use and student use of computers

    Science.gov (United States)

    Kerr, Rebecca

    The purpose of this descriptive quantitative and basic qualitative study was to examine fifth and eighth grade science teachers' responses, perceptions of the role of technology in the classroom, and how they felt that computer applications, tools, and the Internet influence student understanding. The purposeful sample included survey and interview responses from fifth grade and eighth grade general and physical science teachers. Even though they may not be generalizable to other teachers or classrooms due to a low response rate, findings from this study indicated teachers with fewer years of teaching science had a higher level of computer use but less computer access, especially for students, in the classroom. Furthermore, teachers' choice of professional development moderated the relationship between the level of school performance and teachers' knowledge/skills, with the most positive relationship being with workshops that occurred outside of the school. Eighteen interviews revealed that teachers perceived the role of technology in classroom instruction mainly as teacher-centered and supplemental, rather than student-centered activities.

  18. How Shall We Tell Our People? The Art and Science of Communicating Sea-Level Rise to Coastal Audiences (Invited)

    Science.gov (United States)

    Moser, S. C.

    2010-12-01

    Improved sea-level rise projections and translation into decision-relevant information (e.g., changed flood frequencies and elevations, increased rates in coastal erosion, salinity changes in coastal aquifers) are critical for coastal managers, planners, and local elected officials to feel more confident in bringing climate change and its related coastal impacts to the attention of their communities. Those who have done so or are considering doing so, however, are not just concerned with “getting the science right” or getting the most credible and relevant information. They immediately, and sometimes primarily, are concerned with the reactions of coastal residents, developers, and business interests to the prospects of potentially difficult and substantial changes in coastal land use, their property rights, and the potential loss of their homes and establishments. How to engage the public constructively in developing adaptation strategies is a largely unmet challenge for most coastal managers. Similarly, they have not been trained in how to effectively communicate an issue that is ripe with the potential for loss, danger, and social and legal conflict - more so than they already face. Better physical science on sea-level rise alone will not meet these needs. Meanwhile, the social sciences have only begun to study public attitudes toward local impacts and adaptation responses. This paper will summarize key insights available at this time and point to important research and education/training needs to better assist practitioners faced with developing and implementing coastal adaptation strategies.

  19. A Comparative Study of the Quality of Teaching Learning Process at Post Graduate Level in the Faculty of Science and Social Science

    Science.gov (United States)

    Shahzadi, Uzma; Shaheen, Gulnaz; Shah, Ashfaque Ahmed

    2012-01-01

    The study was intended to compare the quality of teaching learning process in the faculty of social science and science at University of Sargodha. This study was descriptive and quantitative in nature. The objectives of the study were to compare the quality of teaching learning process in the faculty of social science and science at University of…

  20. Time lag between the tropopause height and the levels of 7Be concentration in near surface air

    Science.gov (United States)

    Ioannidou, A.; Vasileiadis, A.; Melas, D.

    2012-04-01

    The concentration of 7Be at near surface air has been determined over 2009, a year of a deep solar minimum, in the region of Thessaloniki, Greece at 40°62' N, 22°95'E. In geomagnetic latitudes over 40° N, the elevation of the tropopause during the warm summer months and the vertical exchange of air masses within the troposphere cause greater mixture of the air masses resulting in higher concentration levels for 7Be in surface air. The positive correlation between the monthly activity concentration of 7Be and the tropopause height (0.94, p rate of vertical transport within the troposphere, especially during warmer summer months, has as a result the descent to surface of air masses enriched in 7Be. However, the 7Be concentration levels in near surface air are not expected to respond immediately to the change of elevation of the tropopause. It was found that there's a time lag of ~ 3 days between the change in the daily surface concentrations of 7Be the change in the elevation of the tropopause.

  1. Microbiological levels of randomly selected food contact surfaces in hotels located in Spain during 2007-2009.

    Science.gov (United States)

    Doménech-Sánchez, Antonio; Laso, Elena; Pérez, María José; Berrocal, Clara Isabel

    2011-09-01

    The aim of this study was to survey the microbial levels of food contact surfaces in hotels. Microbiological levels of 4611 surfaces (chopping machines, kitchenware, knives, worktops, and cutting boards) from 280 different facilities in Spain were determined in a 3-year period. The contact-plate technique was used throughout the survey. Overall, the mean of the log of total aerobic count cm(-2) was 0.62, better than those reported for child-care and assisted living facilities. Significant differences were detected among different types of surfaces, time of sampling, season, and year. The majority (74%) of food contact surfaces sampled in Spanish hotels was within the recommended standard of <1.3 log CFU cm(-2), and differences depend on several factors. Our results set a representative picture of the actual situation in our resorts and establish the basis for the development of educational programs to improve food handlers' knowledge of foodborne diseases and their transmission via food contact surfaces.

  2. Time lag between the tropopause height and the levels of 7Be concentration in near surface air

    Directory of Open Access Journals (Sweden)

    Melas D.

    2012-04-01

    Full Text Available The concentration of 7Be at near surface air has been determined over 2009, a year of a deep solar minimum, in the region of Thessaloniki, Greece at 40°62′ N, 22°95'E. In geomagnetic latitudes over 40° N, the elevation of the tropopause during the warm summer months and the vertical exchange of air masses within the troposphere cause greater mixture of the air masses resulting in higher concentration levels for 7Be in surface air. The positive correlation between the monthly activity concentration of 7Be and the tropopause height (0.94, p < 0.0001, and also between 7Be concentration and the temperature T (°C (R = 0.97, p < 0.001, confirm that the increased rate of vertical transport within the troposphere, especially during warmer summer months, has as a result the descent to surface of air masses enriched in 7Be. However, the 7Be concentration levels in near surface air are not expected to respond immediately to the change of elevation of the tropopause. It was found that there's a time lag of ~ 3 days between the change in the daily surface concentrations of 7Be the change in the elevation of the tropopause.

  3. Food formulation and not processing level: Conceptual divergences between public health and food science and technology sectors.

    Science.gov (United States)

    Botelho, R; Araújo, W; Pineli, L

    2018-03-04

    Observed changes in eating and drinking behaviors in economically developing countries are associated with increase of obesity and related chronic diseases. Researchers from field of public health (PH) have attributed this problem to food processing and have created new food classification systems to support their thesis. These classifications conceptually differ from processing level concepts in food science, and state to people that food processing is directly related to nutritional impact of food. Our work aims to compare the concept of food processing from the standpoint of food science and technology (FST) and public health and to discuss differences related to formulation or level of processing of products and their impact on nutritional quality. There is a misconception between food processing/unit operation/food technology and formulation or recipes. For the public health approach, classification is based on food products selection and the use of ingredients that results in higher consumption of sugar, sodium, fat, and additives, whereas in FST, processing level is based on the intensity and amount of unit operations to enhance shelf life, food safety, food quality, and availability of edible parts of raw materials. Nutritional quality of a product or preparation is associated with formulation/recipe and not with the level of processing, with few exceptions. The impact of these recommendations on the actual comprehension of food processing and quality must be considered by the population.

  4. Surface Science in an MOCVD Environment: Arsenic on Vicinal Ge(100)

    International Nuclear Information System (INIS)

    Olson, J.M.; McMahon, W.E.

    1998-01-01

    Scanning tunneling microscope (STM) images of arsine-exposed vicinal Ge(100) surfaces show that most As/Ge steps are reconstructed, and that a variety of different step structures exist. The entire family of reconstructed As/Ge steps can be divided into two types, which we have chosen to call ''single-row'' steps and ''double-row'' steps. In this paper we propose a model for a double-row step created by annealing a vicinal Ge(100) substrate under an arsine flux in a metal-organic chemical vapor deposition (MOCVD) chamber

  5. What Are Normal Metal Ion Levels After Total Hip Arthroplasty? A Serologic Analysis of Four Bearing Surfaces.

    Science.gov (United States)

    Barlow, Brian T; Ortiz, Philippe A; Boles, John W; Lee, Yuo-Yu; Padgett, Douglas E; Westrich, Geoffrey H

    2017-05-01

    The recent experiences with adverse local tissue reactions have highlighted the need to establish what are normal serum levels of cobalt (Co), chromium (Cr), and titanium (Ti) after hip arthroplasty. Serum Co, Cr, and Ti levels were measured in 80 nonconsecutive patients with well-functioning unilateral total hip arthroplasty and compared among 4 bearing surfaces: ceramic-on-ceramic (CoC); ceramic-on-polyethylene (CoP); metal-on-polyethylene (MoP), and dual mobility (DM). The preoperative and most recent University of California, Los Angeles (UCLA) and Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores were compared among the different bearing surfaces. No significant difference was found among serum Co and Cr levels between the 4 bearing surface groups (P = .0609 and P = .1577). Secondary analysis comparing metal and ceramic femoral heads demonstrated that the metal group (MoP, modular dual mobility (Stryker Orthopedics, Mahwah, NJ) [metal]) had significant higher serum Co levels compared with the ceramic group (CoC, CoP, MDM [ceramic]) (1.05 mg/L ± 1.25 vs 0.59 mg/L ± 0.24; P = .0411). Spearman coefficient identified no correlation between metal ion levels and patient-reported outcome scores. No serum metal ion level differences were found among well-functioning total hip arthroplasty with modern bearing couples. Significantly higher serum Co levels were seen when comparing metal vs ceramic femoral heads in this study and warrants further investigation. Metal ion levels did not correlate with patient-reported outcome measures. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. A process-level attribution of the annual cycle of surface temperature over the Maritime Continent

    Science.gov (United States)

    Li, Yana; Yang, Song; Deng, Yi; Hu, Xiaoming; Cai, Ming

    2017-12-01

    The annual cycle of the surface temperature over the Maritime Continent (MC) is characterized by two periods of rapid warming in March-April and September-October, respectively, and a period of rapid cooling in June-July. Based upon an analysis of energy balance within individual atmosphere-surface columns, the seasonal variations of surface temperature in the MC are partitioned into partial temperature changes associated with various radiative and non-radiative (dynamical) processes. The seasonal variations in direct solar forcing and surface latent heat flux show the largest positive contributions to the annual cycle of MC surface temperature while the changes in oceanic dynamics (including ocean heat content change) work against the temperature changes related to the annual cycle. The rapid warming in March-April is mainly a result of the changes in atmospheric quick processes and ocean-atmosphere coupling such as water vapor, surface latent heat flux, clouds, and atmospheric dynamics while the contributions from direct solar forcing and oceanic dynamics are negative. This feature is in contrast to that associated with the warming in September-October, which is driven mainly by the changes in solar forcing with a certain amount of contributions from water vapor and latent heat flux change. More contribution from atmospheric quick processes and ocean-atmosphere coupling in March-April coincides with the sudden northward movement of deep convection belt, while less contribution from these quick processes and coupling is accompanied with the convection belt slowly moving southward. The main contributors to the rapid cooling in June-July are the same as those to the rapid warming in March-April, and the cooling is also negatively contributed by direct solar forcing and oceanic dynamics. The changes in water vapor in all three periods contribute positively to the change in total temperature and they are associated with the change in the location of the center of

  7. Tank 241-SY-101 surface level rise remediation test and evaluation plan for transfer system

    International Nuclear Information System (INIS)

    BAUER, R.E.

    1999-01-01

    The purpose of this testing and evaluation plan (TEP) is to provide the high level guidance on testing requirements for ensuring that the equipment and systems to be implemented for remediation of the SY-101 waste level rise USQ are effective

  8. Preservice Science Teachers’ Levels of Associating The Concept of Gas Pressure with Everyday Life

    Directory of Open Access Journals (Sweden)

    Aybüke Pabuçcu

    2016-10-01

    Full Text Available Through this research, it was aimed to investigate how pre-service science teachers’ use their knowledge about the concept of gas pressure in explaining some examples from everyday life. The research was carried out with 33 freshmen pre-service science teachers. The data in the research were collected through five formative assessment probes. The students were asked to work in small groups to complete the questions. Groups’ discussions were recorded. Groups’ written responses were classified in five different categories: sound understanding, partial understanding, specific misconception, no understanding, and no response. Data under these categories were given as percentages in a table. The sum of students’ responses in sound understanding and partial understanding are in the range of 37.5% and 62.5%. Results revealed that students had difficulty in understanding the gases concepts and associating these concepts with everyday life events. Moreover, many misconceptions and misuse of the ideal gas equation were determined in the students’ explanations.

  9. Planetary Sciences practical experiences at the Master level with small telescopes

    Science.gov (United States)

    Sanchez-Lavega, A.; Perez-Hoyos, S.; del Rio-Gaztelurrutia, T.; Hueso, R.; Ordonez Etxeberria, I.; Rojas, J. F.

    2016-12-01

    The Master in Space Science and Technology of the Basque Country University UPV/EHU in Bilbao (Spain) has been taught during 7 years (A. Sanchez-Lavega et al., Eur. J. of Eng. Education. 2014). Along the different courses, a series of practical observations and studies of planetary sciences have been conducted with Master students, using telescopes with diameters in the range 28-50 cm pertaining to the Aula EspaZio Gela Observatory (http://www.ehu.eus/aula-espazio/presentacion.html). Simple instrumentation (cameras and a spectrograph) have been employed to study planetary atmospheres (dynamics and cloud structure) and orbital mechanics using the Galilean satellites. Here we present a sample of these studies, which have lead to publications in refereed journals and have been presented at different meetings with the coauthoring of the students. Plans for the future include involving the master students in high-resolution observations of Solar System planets using a remote controlled 36 cm telescope at the Calar Alto observatory in Southern Spain (separated 1000 km from the teaching facilities in Bilbao).

  10. Nitrogen cycle: approach in Science textbooks for the junior Higt Level 1

    Directory of Open Access Journals (Sweden)

    Angela Fernandes Campos

    2008-01-01

    Full Text Available This paper features as its theme the approach to Nitrogen Cycle in textbooks. The goal is to tell whether the Science textbooks focus on an adequate approach to such a cycle, so that it meets the teacher`s needs. This content was defined because we understand that its study is of the utmost importance, due to the fact that on such a cycle depend nature`s energetic balance, the preservation of the richness of the soil in nutrients and the formation of the nitrogenous compounds which are vital to the organism of all living beings. The research work was carried out by means of the analysis of the Science textbooks recommended by The Textbook Guide 2005, taking into account that, supposedly, upon being approved and suggested by PNLD, they are already qualified to be adopted by teachers. With this research, we came to the conclusion that there are different limits when the Nitrogen Cycle is approached in textbooks. Such finding is not enough for the solution to a real problem; it is believed, however, that perceiving the existence of that problem and understanding what causes is to happen tends to make a possible answer to such a question less distant and conflicting.

  11. The Effect of Technology-Based Altered Readability Levels on Struggling Readers' Science Comprehension

    Science.gov (United States)

    Marino, Matthew T.; Coyne, Michael; Dunn, Michael

    2010-01-01

    This article reports findings from a study examining how altered readability levels affected struggling readers' (N = 288) comprehension of scientific concepts and vocabulary. Specifically, the researchers were interested in learning what effect altered readability levels have when low ability readers participate in a technology-based science…

  12. An Overview of Some Natural Products with Two A-Level Science Club Natural Products Experiments

    Science.gov (United States)

    Sosabowski, Michael Hal; Olivier, George W. J.; Jawad, Hala; Maatta, Sieja

    2017-01-01

    Natural products are ubiquitous in nature but do not form a large proportion of the A-level syllabuses in the UK. In this article we briefly discuss a small selection of natural products, focusing on alcohols, aldehydes and ketones, and alkaloids. We then outline two natural product experiments that are suitable for A-level chemistry clubs or…

  13. Martian Surface Boundary Layer Characterization: Enabling Environmental Data for Science, Engineering and Human Exploration

    Science.gov (United States)

    England, C.

    2000-01-01

    For human or large robotic exploration of Mars, engineering devices such as power sources will be utilized that interact closely with the Martian environment. Heat sources for power production, for example, will use the low ambient temperature for efficient heat rejection. The Martian ambient, however, is highly variable, and will have a first order influence on the efficiency and operation of all large-scale equipment. Diurnal changes in temperature, for example, can vary the theoretical efficiency of power production by 15% and affect the choice of equipment, working fluids, and operating parameters. As part of the Mars Exploration program, missions must acquire the environmental data needed for design, operation and maintenance of engineering equipment including the transportation devices. The information should focus on the variability of the environment, and on the differences among locations including latitudes, altitudes, and seasons. This paper outlines some of the WHY's, WHAT's and WHERE's of the needed data, as well as some examples of how this data will be used. Environmental data for engineering design should be considered a priority in Mars Exploration planning. The Mars Thermal Environment Radiator Characterization (MTERC), and Dust Accumulation and Removal Technology (DART) experiments planned for early Mars landers are examples of information needed for even small robotic missions. Large missions will require proportionately more accurate data that encompass larger samples of the Martian surface conditions. In achieving this goal, the Mars Exploration program will also acquire primary data needed for understanding Martian weather, surface evolution, and ground-atmosphere interrelationships.

  14. Metal/metal-oxide interfaces: A surface science approach to the study of adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Peden, C.H.F.; Kidd, K.B.; Shinn, N.D. (Sandia National Laboratories, Albuquerque, New Mexico 87185-5800 (USA))

    1991-05-01

    Metal-oxide/metal interfaces play an important role, for example, in the joining of an oxide ceramic to a metal for sealing applications. In order to probe the chemical and physical properties of such an interface, we have performed Auger electron spectroscopic (AES) and temperature programed desorption (TPD) experiments on a model system composed of very thin films of Cr, Fe, Ni, or Cu evaporated onto a very thin thermally grown oxide on a W single crystal. Monolayer films of Fe and Cr were found (by AES) to completely wet the oxide surface upon deposition, and were stable up to temperatures at which the films desorbed ({approx}1300 K). In contrast, monolayer Ni and Cu films formed three-dimensional islands exposing the oxidized W surface either upon annealing (Ni) or even upon room-temperature deposition (Cu). The relative interfacial interaction between the overlayer metal and the oxide, as assessed by TPD, increases in the series Cu{lt}Ni{lt}Fe{lt}Cr. This trend follows the heats of formation of the various oxides of these metals.

  15. Investigation of anti-Relaxation coatings for alkali-metal vapor cells using surface science techniques

    Energy Technology Data Exchange (ETDEWEB)

    Seltzer, S. J.; Michalak, D. J.; Donaldson, M. H.; Balabas, M. V.; Barber, S. K.; Bernasek, S. L.; Bouchiat, M.-A.; Hexemer, A.; Hibberd, A. M.; Jackson Kimball, D. F.; Jaye, C.; Karaulanov, T.; Narducci, F. A.; Rangwala, S. A.; Robinson, H. G.; Shmakov, A. K.; Voronov, D. L.; Yashchuk, V. V.; Pines, A.; Budker, D.

    2010-10-11

    Many technologies based on cells containing alkali-metal atomic vapor benefit from the use of antirelaxation surface coatings in order to preserve atomic spin polarization. In particular, paraffin has been used for this purpose for several decades and has been demonstrated to allow an atom to experience up to 10?000 collisions with the walls of its container without depolarizing, but the details of its operation remain poorly understood. We apply modern surface and bulk techniques to the study of paraffin coatings in order to characterize the properties that enable the effective preservation of alkali spin polarization. These methods include Fourier transform infrared spectroscopy, differential scanning calorimetry, atomic force microscopy, near-edge x-ray absorption fine structure spectroscopy, and x-ray photoelectron spectroscopy. We also compare the light-induced atomic desorption yields of several different paraffin materials. Experimental results include the determination that crystallinity of the coating material is unnecessary, and the detection of C=C double bonds present within a particular class of effective paraffin coatings. Further study should lead to the development of more robust paraffin antirelaxation coatings, as well as the design and synthesis of new classes of coating materials.

  16. Distribution of energy levels of quantum free particle on the Liouville surface and trace formulae

    International Nuclear Information System (INIS)

    Bleher, P.M.; Kosygin, D.V.; Sinai, Y.G.

    1995-01-01

    We consider the Weyl asymptotic formula [{E n ≤R 2 }=Area Q.R 2 /(4π)+n(R), for eigenvalues of the Laplace-Beltrami operator on a two-dimensional torus Q with a Liouville metric which is in a sense the most general case of an integrable metric. We prove that if the surface Q is non-degenerate then the remainder term n(R) has the form n(R)=R 1/2 θ(R), where θ(R) is an almost periodic function of the Besicovitch class B 1 , and the Fourier amplitudes and the Fourier frequencies of θ(R) can be expressed via lengths of closed geodesics on Q and other simple geometric characteristics of these geodesics. We prove then that if the surface Q is generic then the limit distribution of θ(R) has a density p(t), which is an entire function of t possessing an asymptotics on a real line, logp(t)∝-C ± t 4 as t→±∞. An explicit expression for the Fourier transform of p(t) via Fourier amplitudes of θ(R) is also given. We obtain the analogue of the Guillemin-Duistermaat trace formula for the Liouville surfaces and discuss its accuracy. (orig.)

  17. Electron/positron measurements obtained with the Mars Science Laboratory Radiation Assessment Detector on the surface of Mars

    Energy Technology Data Exchange (ETDEWEB)

    Koehler, J.; Wimmer-Schweingruber, R.F.; Appel, J. [Kiel Univ. (Germany). Inst. of Experimental and Applied Physics; and others

    2016-04-01

    The Radiation Assessment Detector (RAD), on board the Mars Science Laboratory (MSL) rover Curiosity, measures the energetic charged and neutral particles and the radiation dose rate on the surface of Mars. Although charged and neutral particle spectra have been investigated in detail, the electron and positron spectra have not been investigated yet. The reason for that is that they are difficult to separate from each other and because of the technical challenges involved in extracting energy spectra from the raw data. We use GEANT4 to model the behavior of the RAD instrument for electron/positron measurements.We compare Planetocosmics predictions for different atmospheric pressures and different modulation parameters Φ with the obtained RAD electron/positron measurements.We find that the RAD electron/positron measurements agree well with the spectra predicted by Planetocosmics. Both RAD measurements and Planetocosmics simulation show a dependence of the electron/positron fluxes on both atmospheric pressure and solar modulation potential.

  18. Science education through open and distance learning at Higher Education level

    Directory of Open Access Journals (Sweden)

    Amrita NIGAM

    2007-10-01

    Full Text Available Abstract The changes faced by the society in the past few decades brought revolution in all areas. The job requirements have undergone change tremendously. The emergence of e-culture, e-education, e-governance, e-training, e-work sites and so on questioned the capacity of conventional face to face education in catering to all and relevance of existing job related skills to a great extent in the emerging global society. Today, every one has to update his/her educational and/or professional skills and competencies to cope up with the emerging work challenges. This is more so in the field of science and technology. At the same time, it is impossible to cater to educational and training opportunities to one and all those who aspire for it through the conventional set up. The distance and open learning (ODL seems to be one of the viable alternatives. Today, the success and viability of ODL is accepted globally. Coulter (1989, through a study demonstrated that ODL is a cost-effective medium in providing educational opportunities. Similarly Holmberg (1981 also mentioned ODL as a systematic teaching-learning medium by using variety of medium for imparting learning. The present study is an attempt to study the experiences of the open science learners of IGNOU on different aspect of the science higher education. Here a questionnaire was used to collect the data and responses from 81 students enrolled for B. Sc. from IGNOU were collected. The findings of the study reported that society has undergone drastic changes in the last few decades. The revolution led due to Information and Communication Technologies (ICTs have widely affected all aspects of society. The emerging jobs require entirely new skills and competencies i.e., employment in BPOs or switching over to e-governance, e-Banking and e- based sectors. Even e-learning has made numerous expectations from teachers and other personnel. The use of ICTs in almost every field needs adequately trained

  19. Dynamic factor modeling of ground and surface water levels in an agricultural area adjacent to Everglades National Park

    Science.gov (United States)

    Ritter, A.; Muñoz-Carpena, R.

    2006-02-01

    The extensive eastern boundary of Everglades National Park (ENP) in south Florida (USA) is subject to one the most expensive and ambitious environmental restoration projects in history. Understanding and predicting the interaction between the shallow aquifer and surface water is a key component for fine-tuning the process. The Frog Pond is an intensively instrumented agricultural 2023 ha area adjacent to ENP. The interactions among 21 multivariate daily time series (ground and surface water elevations, rainfall and evapotranspiration) available from this area were studied by means of dynamic factor analysis, a novel technique in the field of hydrology. This method is designed to determine latent or background effects governing variability or fluctuations in non-stationary time series. Water levels in 16 wells and two drainage ditch locations inside the area were selected as response variables, and canal levels and net recharge as explanatory variables. Elevations in the two canals delimiting the Frog Pond area were found to be the main factors explaining the response variables. This influence of canal elevations on water levels inside the area was complementary and inversely related to the distance between the observation point and each canal. Rainfall events do not affect daily water levels significantly but are responsible for instantaneous or localized groundwater responses that in some cases can be directly associated with the risk of flooding. This close coupling between surface and groundwater levels, that corroborates that found by other authors using different methods, could hinder on-going environmental restoration efforts in the area by bypassing the function of wetlands and other surface features. An empirical model with a reduced set of parameters was successfully developed and validated in the area by interpolating the results from the dynamic factor analysis across the spatial domain (coefficient of efficiency across the domain: 0.66-0.99). Although

  20. Low energy level density and surface instabilities in heavy transition nuclei

    International Nuclear Information System (INIS)

    Wieclawik, W. de; Foucher, R.; Dionisio, J.S.; Vieu, C.; Hoglund, A.; Watzig, W.

    1975-01-01

    A statistical analysis of Au, Pt, Hg nuclear levels was performed with Ericson's method. The odd mass gold experimental number of levels distributions are compared to the theoretical distributions corresponding to vibrational (Alaga and Kisslinger-Sorensen) and rotational (Stephens, Meyer-ter-Vehn) models. The Alaga model gives the most complete description of 193 Au, 195 Au levels and fits the lowest part of Gilbert-Cameron high energy distributions (deduced from the statistical model and neutron capture data). The Ericson's method shows other interesting features of Pt and Hg isotopes (i.e. level density dependence on nuclear shape and pairing correlations, evidence for phase transitions). Consequently, this method is a useful tool for guiding experimental as well as theoretical investigations of transition nuclei [fr

  1. Interpreting Changes in Surface EMG Amplitude During High-Level Fatiguing Contractions of the Brachioradialis

    National Research Council Canada - National Science Library

    Lowery, M

    2001-01-01

    .... It is proposed that using these relationships, under conditions where motor unit recruitment and synchronization can be assumed to be negligible, such as at high force levels or in smaller muscles...

  2. Biomimetics Bioinspired Hierarchical-Structured Surfaces for Green Science and Technology

    CERN Document Server

    Bhushan, Bharat

    2012-01-01

    This book presents an overview of the general field of biomimetics - lessons from nature. It presents various examples of biomimetics, including roughness-induced superomniphobic surfaces which provide functionality of commercial interest. The major focus in the book is on lotus effect, rose petal effect, shark skin effect, and gecko adhesion.  For each example, the book first presents characterization of an object to understand how a natural object provides functionality, followed by modeling and then fabrication of structures in the lab using nature’s route to verify one’s understanding of nature and provide guidance for development of optimum structures. Once it is understood how nature does it, examples of fabrication of optimum structures using smart materials and fabrication techniques, are presented. Examples of nature inspired objects are also presented throughout.

  3. Electron paramagnetic resonance and dynamic nuclear polarization of char suspensions: surface science and oximetry

    International Nuclear Information System (INIS)

    Clarkson, R.B.; Odintsov, B.M.; Ceroke, P.J.; Ardenkjaer-Larsen, J.H.; Fruianu, M.; Belford, R.L.

    1998-01-01

    Carbon chars have been synthesized in our laboratory from a variety of starting materials, by means of a highly controlled pyrolysis technique. These chars exhibit electron paramagnetic resonance (EPR) line shapes which change with the local oxygen concentration in a reproducible and stable fashion; they can be calibrated and used for oximetry. Biological stability and low toxicity make chars good sensors for in vivo measurements. Scalar and dipolar interactions of water protons at the surfaces of chars may be utilized to produce dynamic nuclear polarization (DNP) of the 1 H nuclear spin population in conjunction with electron Zeeman pumping. Low-frequency EPR, DNP and DNP-enhanced MRI all show promise as oximetry methods when used with carbon chars. (author)

  4. Journal of Earth System Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science. Bhawanisingh G Desai. Articles written in Journal of Earth System Science. Volume 120 Issue 4 August 2011 pp 723-734. Discontinuity surfaces and event stratigraphy of Okha Shell Limestone Member: Implications for Holocene sea level changes, western India.

  5. Cell surface N-glycans influence the level of functional E-cadherin at the cell–cell border

    Directory of Open Access Journals (Sweden)

    M. Kristen Hall

    2014-01-01

    Full Text Available E-cadherin is crucial for adhesion of cells to each other and thereby development and maintenance of tissue. While it is has been established that N-glycans inside the cell impact the level of E-cadherin at the cell surface of epithelial-derived cells, it is unclear whether N-glycans outside the cell control the clustering of E-cadherin at the cell–cell border. Here, we demonstrate reduction of N-glycans at the cell surface weakened the recruitment and retention of E-cadherin at the cell–cell border, and consequently reduced the strength of cell–cell interactions. We conclude that N-glycans at the cell surface are tightly linked to the placement of E-cadherin at the cell–cell border and thereby control E-cadherin mediated cell–cell adhesion.

  6. Relative impacts of worldwide tropospheric ozone changes and regional emission modifications on European surface-ozone levels

    International Nuclear Information System (INIS)

    Szopa, S.; Hauglustaine, D.A.

    2007-01-01

    Multi-scale models were applied to assess the surface ozone changes in 2030. Several emission scenarios are considered, ranging from (a) a pessimistic anthropogenic emission increase to (b) an optimistic decrease of emissions, and including (c) a realistic scenario that assumes the implementation of control legislations [CLE]. The two extreme scenarios lead respectively to homogeneous global increase and decrease of surface ozone, whereas low and inhomogeneous changes associated with a slight global increase of ozone are found for the CLE scenario. Over western Europe, for the CLE scenario, the benefit of European emission reduction is significantly counterbalanced by increasing global ozone levels. Considering warmer conditions over Europe and future emission modifications, the human health exposure to surface ozone is found to be significantly worsened. (authors)

  7. GHRSST Level 2P Atlantic Regional Bulk Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-16 satellite (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A regional Level 2P Group for High Resolution Sea Surface Temperature (GHRSST) dataset for the Atlantic Ocean and nearby regions based on multi-channel sea surface...

  8. GHRSST Level 2P Global Bulk Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-17 satellite produced by NAVO (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A global Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  9. GHRSST Level 2P Global Bulk Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-17 satellite (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A global Level 2P Group for High Resolution Sea Surface Temperature (GHRSST) dataset based on multi-channel sea surface temperature (SST) retrievals from the...

  10. GHRSST Level 4 AVHRR_OI Global Blended Sea Surface Temperature Analysis (GDS version 2) from NCEI (GDS versions 1 and 2)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Group for High Resolution Sea Surface Temperature (GHRSST) global Level 4 sea surface temperature analysis produced daily on a 0.25 degree grid at the NOAA...

  11. GHRSST Level 2P Global Bulk Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-16 satellite (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A global Level 2P Group for High Resolution Sea Surface Temperature (GHRSST) dataset based on multi-channel sea surface temperature (SST) retrievals from the...

  12. GHRSST Level 2P Regional Bulk Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-18 satellite produced by NAVO (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A regional Group for High Resolution Sea Surface Temperature (GHRSST) Level 2P dataset based on multi-channel sea surface temperature (SST) retrievals generated in...

  13. GHRSST Level 2P Atlantic Regional Bulk Sea Surface Temperature from the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-17 satellite (GDS version 1)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A regional Level 2P Group for High Resolution Sea Surface Temperature (GHRSST) dataset for the Atlantic Ocean and nearby regions based on multi-channel sea surface...

  14. Implications of long-term surface or near-surface storage of intermediate and low-level wastes in the UK

    International Nuclear Information System (INIS)

    Murray, N.; Vande Putte, D.; Ware, R.J.

    1986-02-01

    Various options for 200 year-long storage of all Low- and Intermediate-Level wastes generated to the year 2030 are considered. On-site storage and centralised storage have been examined and compared. The feasibility of storing some of the wastes in underground facilities that are convertible to repositories has been demonstrated, but it is shown that centralised, surface storage of wastes would be more economical. There appears to be little merit in storing Intermediate Level wastes in separate facilities that could be converted to repositories. Storage is shown to be more expensive than direct disposal, except if future costs are discounted by more than about 10%. With carefully designed stores and remote handling, the collective dose to operators could be limited to about 20-40 man Sv over the whole period of storage. (author)

  15. High resolution spectroscopy on adsorbed molecules on a Ni (110)-surface: vibrational states and electronic levels

    International Nuclear Information System (INIS)

    Kardinal, I.

    1998-01-01

    The complementary techniques of HR-XPS and HREELS have been applied to two distinct problems. The first studies adsorption and dissociation of C 2 N 2 on Ni (110) at room temperature (RT) and at 90 K and its co-adsorption with CO. At RT C 2 N 2 dissociates and forms a c(2x2)-CN structure. The resulting CN is found to be bound in the grooves of the (110) surface yielding the lowest C-N vibrational energy yet observed. C 2 N 2 was found to dissociate even at 90 K however the resulting CN overlayer after warming to RT showed remarkable differences to that of the RT adsorption. As well as the in-groove species a number of adsorption sites on the ridges with a bond order higher have been identified. Preadsorbed CO is completely driven of the Ni (110) surface by co-adsorption of CN at RT. HREELS indicates that first CO is desorbed from the on-top-sites and then from the bridge-sites of the (110)-ridges involving a considerable increase of the HREELS cross section for the CO on the bridge-sites. Also the signal intensity of the coadsorbed CN is suppressed by the CO present on the surface. The second study investigated the adsorption of bithiophene (BiT) on clean Ni (110) and the S-modified c(2x2)-S-Ni (110) and p(4x1)-S-Ni (110). The latter provided a strongly structured substrate which forced the assembly of the adsorbed BiT-molecules. The high degree of order of this adsorbate/substrate system was obvious in both the HR-XPS results and the BREELS results with strong azimuthal anisotropy. This system was used to asses the ability to use the HREELS impact selection rules to determine molecular orientation of a reasonably complex adsorbate overlayer. (author)

  16. Investigating oligonucleotide hybridization at subnanomolar level by surface plasmon resonance biosensor method

    Czech Academy of Sciences Publication Activity Database

    Vaisocherová, Hana; Zítová, Alice; Lachmanová, Markéta; Štepánek, J.; Králíková, Šárka; Liboska, Radek; Rejman, Dominik; Rosenberg, Ivan; Homola, Jiří

    2006-01-01

    Roč. 82, č. 4 (2006), s. 394-398 ISSN 0006-3525. [European Conference on the Spectroscopy of Biological Molecules - ECSBM 2005 /11./. Aschaffenburg, 03.09.2005-08.09.2005] R&D Projects: GA ČR(CZ) GA303/03/0249; GA ČR(CZ) GA102/03/0633; GA ČR(CZ) GA202/05/0628 Institutional research plan: CEZ:AV0Z20670512; CEZ:AV0Z40550506 Keywords : surface plasmon resonance * biosensors * optical sensors Subject RIV: BO - Biophysics Impact factor: 2.480, year: 2006

  17. Concentration of sunlight to solar-surface levels using non-imaging optics

    Science.gov (United States)

    Gleckman, Philip; O'Gallagher, Joseph; Winston, Roland

    1989-05-01

    An account is given of the design and operational principles of a solar concentrator that employs nonimaging optics to achieve a solar flux equal to 56,000 times that of ambient sunlight, yielding temperatures comparable to, and with further development of the device, exceeding those of the solar surface. In this scheme, a parabolic mirror primary concentrator is followed by a secondary concentrator, designed according to the edge-ray method, which is filled with a transparent oil. The device may be used in materials-processing, waste-disposal, and solar-pumped laser applications.

  18. The high-level error bound for shifted surface spline interpolation

    OpenAIRE

    Luh, Lin-Tian

    2006-01-01

    Radial function interpolation of scattered data is a frequently used method for multivariate data fitting. One of the most frequently used radial functions is called shifted surface spline, introduced by Dyn, Levin and Rippa in \\cite{Dy1} for $R^{2}$. Then it's extended to $R^{n}$ for $n\\geq 1$. Many articles have studied its properties, as can be seen in \\cite{Bu,Du,Dy2,Po,Ri,Yo1,Yo2,Yo3,Yo4}. When dealing with this function, the most commonly used error bounds are the one raised by Wu and S...

  19. Polymer and Surface Science in Europe, Israel, and Egypt: Some Observations,

    Science.gov (United States)

    1981-11-25

    scientist funding a university colleague to work jointly on some specific topic of mutual interest. The concept of a contract manager monitoring a...de Documentation du Verre Textile et des Plastiques Renforc’s, Paris, on 28 March 1979 (ESN 33-9:368 (19791 I had a qlimpse of the level of industrial...The University of Alexandria Research Center (UNARC) was started with considerable financial help from UNESCO. The concept and formation of UNARC

  20. The impact of an introductory college-level biology class on biology self-efficacy and attitude towards science

    Science.gov (United States)

    Thomas, Megan Elizabeth

    Self-efficacy theory was first introduced in a seminal article by Albert Bandura in 1977 entitled "Self-efficacy: Toward a unifying theory of behavioral change". Since its original introduction, self-efficacy has been a major focus of academic performance, anxiety, career development, and teacher retention research. Self-efficacy can be defined as the belief an individual possesses about their ability to perform a given task. Bandura proposed that self-efficacy should be measured at the highest level of specificity due to the fact that different people are efficacious in different areas. Interested in students' efficacy toward biology, Ebert-May, Baldwin, & Allred (1997) created and validated a survey to measure students' biology self-efficacy. Their survey was modeled after the guidelines for science literacy, and loaded to three sub-factors; methods of biology, generalization to other science courses, and application of the concepts. As self-efficacy theory has been related to effort expenditure and persistence (Bandura, 1977; 1997), one might think it would have some effect on students' attitudes toward the topic at hand. The current research investigated what changes in biology self-efficacy occurred after an introductory biology course with an inquiry based laboratory learning environment. In addition, changes in students' attitudes towards science were explored and how self-efficacy might affect them.

  1. The concept of landscape education at school level with respect to the directions of the science of landscape

    Science.gov (United States)

    Szczęsna, Joanna

    2010-01-01

    School education is both a starting point for the development of various scientific disciplines (school educates future researchers) and the result of science. The landscape research is conducted within many scientific disciplines and has a long tradition. Lanscape education, which is the result of a scientific dimension, is implemented in primary school under the nature subject. Primary school education is the only level at which the geographical contents are carried out on landscape. The landscape is of interest to many disciplines: geography, architecture, social sciences and the arts. In recent years, there were many studies which contained an overview of the main strands of the science of landscape, presented the differences in the meaning of the concept and objectives of individual research disciplines. These studies have become the ground for the characterization of the concept of landscape education implemented in Polish school and its evaluation in terms of scientific achievements. A review of educational purposes, the basic content of education and achievements of students, demonstrate the influence of multiple scientific disciplines in school landscape education. The most significant share of the course content are achievements of geography disciplines, particularly: physical geography, environmental protection and landscape ecology. Other scientific fields: literature, art, psychology, sociology, and architecture do not have any impact on the school landscape education or their impact remains marginal.

  2. Control of water infiltration into near surface LLW [low-level radioactive waste] disposal units

    International Nuclear Information System (INIS)

    Schulz, R.K.; Ridky, R.W.; O'Donnell, E.O.

    1990-12-01

    Three kinds of waste disposal unit covers a barriers to water infiltration are being investigated. They are: (1) resistive layer barrier, (2) conductive layer barrier, and (3) bioengineering management. The resistive layer barrier consists of compacted earthen material (e.g. clay). The conductive layer barrier consists of a conductive layer in conjunction with a capillary break. As long as unsaturated flow conditions are maintained the conductive layer will wick water around the capillary break. Below grade layered covers such as (1) and (2) will fail if there is appreciable subsidence of the cover. Remedial action for this kind of failure will be difficult. A surface cover, called bioengineering management, is meant to overcome this problem. The bioengineering management surface barrier is easily repairable if damaged by subsidence; therefore, it could be the system of choice under active subsidence conditions. The bioengineering management procedure also has been shown to be effective in dewatering saturated trenches and could be used for remedial action efforts. After cessation of subsidence, that procedure could be replaced by a resistive layer barrier, or perhaps even better, a resistive layer barrier/conductive layer barrier system. This latter system would then give long-term effective protection against water entry to waste and without institutional care. These various concepts are being assessed in six large (70ft x 45ft x 10ft each) lysimeters at Beltsville, Maryland. 6 refs., 20 figs.,

  3. Trans fatty acids and cholesterol levels: An evidence map of the available science.

    Science.gov (United States)

    Liska, DeAnn J; Cook, Chad M; Wang, Ding Ding; Gaine, P Courtney; Baer, David J

    2016-12-01

    High intakes of industrial trans fatty acids (iTFA) increase circulating low density lipoprotein cholesterol (LDL-C) levels, which has implicated iTFA in coronary heart disease (CHD) risk. Published data on iTFA and LDL-C, however, represent higher intake levels than the U.S. population currently consume. This study used state-of-the-art evidence mapping approaches to characterize the full body of literature on LDL-C and iTFA at low intake levels. A total of 32 independent clinical trials that included at least one intervention or control group with iTFA at ≤3%en were found. Findings indicated that a wide range of oils and interventions were used, limiting the ability to determine an isolated effect of iTFA intake. Few data points were found for iTFA at available to assess the relationship of low levels of iTFA, particularly from PHO exposure, and LDL-C. Therefore, limited evidence is available to determine the effect of iTFA at current consumption levels on CHD risk. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Preterm labor--modeling the uterine electrical activity from cellular level to surface recording.

    Science.gov (United States)

    Rihana, S; Marque, C

    2008-01-01

    Uterine electrical activity is correlated to the appearance of uterine contractions. forceful contractions appear at the end of term. Therefore, understanding the genesis and the propagation of uterine electrical activity may provide an efficient tool to diagnose preterm labor. Moreover, the control of uterine excitability seems to have important consequences in the control of preterm labor. Modeling the electrical activity in uterine tissue is thus an important step in understanding physiological uterine contractile mechanisms and to permit uterine EMG simulation. Our model presented in this paper, incorporates ion channel models at the cell level, the reaction diffusion equations at the tissue level and the spatiotemporal integration at the uterine EMG reconstructed level. This model validates some key physiological observation hypotheses concerning uterine excitability and propagation.

  5. Process-Oriented Guided Inquiry Learning Strategy Enhances Students’ Higher Level Thinking Skills in a Pharmaceutical Sciences Course

    Science.gov (United States)

    Verlinden, Nathan; Kruger, Nicholas; Carroll, Ailey; Trumbo, Tiffany

    2015-01-01

    Objective. To determine if the process-oriented guided inquiry learning (POGIL) teaching strategy improves student performance and engages higher-level thinking skills of first-year pharmacy students in an Introduction to Pharmaceutical Sciences course. Design. Overall examination scores and scores on questions categorized as requiring either higher-level or lower-level thinking skills were compared in the same course taught over 3 years using traditional lecture methods vs the POGIL strategy. Student perceptions of the latter teaching strategy were also evaluated. Assessment. Overall mean examination scores increased significantly when POGIL was implemented. Performance on questions requiring higher-level thinking skills was significantly higher, whereas performance on questions requiring lower-level thinking skills was unchanged when the POGIL strategy was used. Student feedback on use of this teaching strategy was positive. Conclusion. The use of the POGIL strategy increased student overall performance on examinations, improved higher-level thinking skills, and provided an interactive class setting. PMID:25741027

  6. Optical properties and defect levels in a surface layer found on CuInSe{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Abulfotuh, F.; Wangensteen, T.; Ahrenkiel, R.; Kazmerski, L.L. [National Renewable Energy Lab., Golden, CO (United States)

    1996-05-01

    In this paper the authors have used photoluminescence (PL) and wavelength scanning ellipsometry (WSE) to clarify the relationship among the electro-optical properties of copper indium diselenide (CIS) thin films, the type and origin of dominant defect states, and device performance. The PL study has revealed several shallow acceptor and donor levels dominating the semiconductor. PL emission from points at different depths from the surface of the CIS sample has been obtained by changing the angle of incidence of the excitation laser beam. The resulting data were used to determine the dominant defect states as a function of composition gradient at the surface of the chalcopyrite compound. The significance of this type of measurement is that it allowed the detection of a very thin layer with a larger bandgap (1.15-1.26 eV) than the CIS present on the surface of the CIS thin films. The presence of this layer has been correlated by several groups to improvement of the CIS cell performance. An important need that results from detecting this layer on the surface of the CIS semiconductor is the determination of its thickness and optical constants (n, k) as a function of wavelength. The thickness of this surface layer is about 500 {Angstrom}.

  7. NASA's MODIS/VIIRS Land Surface Temperature and Emissivity Products: Asssessment of Accuracy, Continuity and Science Uses

    Science.gov (United States)

    Hulley, G. C.; Malakar, N.; Islam, T.

    2017-12-01

    Land Surface Temperature and Emissivity (LST&E) are an important Earth System Data Record (ESDR) and Environmental Climate Variable (ECV) defined by NASA and GCOS respectively. LST&E data are key variables used in land cover/land use change studies, in surface energy balance and atmospheric water vapor retrieval models and retrievals, and in climate research. LST&E products are currently produced on a routine basis using data from the MODIS instruments on the NASA EOS platforms and by the VIIRS instrument on the Suomi-NPP platform that serves as a bridge between NASA EOS and the next-generation JPSS platforms. Two new NASA LST&E products for MODIS (MxD21) and VIIRS (VNP21) are being produced during 2017 using a new approach that addresses discrepancies in accuracy and consistency between the current suite of split-window based LST products. The new approach uses a Temperature Emissivity Separation (TES) algorithm, originally developed for the ASTER instrument, to physically retrieve both LST and spectral emissivity consistently for both sensors with high accuracy and well defined uncertainties. This study provides a rigorous assessment of accuracy of the MxD21/VNP21 products using temperature- and radiance-based validation strategies and demonstrates continuity between the products using collocated matchups over CONUS. We will further demonstrate potential science use of the new products with studies related to heat waves, monitoring snow melt dynamics, and land cover/land use change.

  8. Cometary science. The organic-rich surface of comet 67P/Churyumov-Gerasimenko as seen by VIRTIS/Rosetta.

    Science.gov (United States)

    Capaccioni, F; Coradini, A; Filacchione, G; Erard, S; Arnold, G; Drossart, P; De Sanctis, M C; Bockelee-Morvan, D; Capria, M T; Tosi, F; Leyrat, C; Schmitt, B; Quirico, E; Cerroni, P; Mennella, V; Raponi, A; Ciarniello, M; McCord, T; Moroz, L; Palomba, E; Ammannito, E; Barucci, M A; Bellucci, G; Benkhoff, J; Bibring, J P; Blanco, A; Blecka, M; Carlson, R; Carsenty, U; Colangeli, L; Combes, M; Combi, M; Crovisier, J; Encrenaz, T; Federico, C; Fink, U; Fonti, S; Ip, W H; Irwin, P; Jaumann, R; Kuehrt, E; Langevin, Y; Magni, G; Mottola, S; Orofino, V; Palumbo, P; Piccioni, G; Schade, U; Taylor, F; Tiphene, D; Tozzi, G P; Beck, P; Biver, N; Bonal, L; Combe, J-Ph; Despan, D; Flamini, E; Fornasier, S; Frigeri, A; Grassi, D; Gudipati, M; Longobardo, A; Markus, K; Merlin, F; Orosei, R; Rinaldi, G; Stephan, K; Cartacci, M; Cicchetti, A; Giuppi, S; Hello, Y; Henry, F; Jacquinod, S; Noschese, R; Peter, G; Politi, R; Reess, J M; Semery, A

    2015-01-23

    The VIRTIS (Visible, Infrared and Thermal Imaging Spectrometer) instrument on board the Rosetta spacecraft has provided evidence of carbon-bearing compounds on the nucleus of the comet 67P/Churyumov-Gerasimenko. The very low reflectance of the nucleus (normal albedo of 0.060 ± 0.003 at 0.55 micrometers), the spectral slopes in visible and infrared ranges (5 to 25 and 1.5 to 5% kÅ(-1)), and the broad absorption feature in the 2.9-to-3.6-micrometer range present across the entire illuminated surface are compatible with opaque minerals associated with nonvolatile organic macromolecular materials: a complex mixture of various types of carbon-hydrogen and/or oxygen-hydrogen chemical groups, with little contribution of nitrogen-hydrogen groups. In active areas, the changes in spectral slope and absorption feature width may suggest small amounts of water-ice. However, no ice-rich patches are observed, indicating a generally dehydrated nature for the surface currently illuminated by the Sun. Copyright © 2015, American Association for the Advancement of Science.

  9. Determination of low-level tritium concentrations in surface water and precipitation in the Czech Republic

    International Nuclear Information System (INIS)

    Maresova, Diana; Hanslik, Eduard; Sedlarova, Barbora; Juranova, Eva; Charles University, Prague

    2017-01-01

    Past tests of nuclear weapons in the atmosphere, nuclear energy facilities and tritium of natural origin are main sources of tritium in the environment. Thanks to its presence in environment and its favourable properties, tritium is used as a radiotracer. Since stopping of atmospheric nuclear tests, tritium in precipitation has been decreasing towards natural levels below 1 Bq l -1 and precise analyses of low level tritium activities are necessary. This paper focuses on tritium development at sites not influenced by any technogenic release of tritium in Elbe River basin (Bohemia) in the Czech Republic using liquid scintillation measurement with electrolytic enrichment. (author)

  10. MO-C-18C-01: Radiation Risks at Level of Few CT Scans: How Real?- Science to Practice

    International Nuclear Information System (INIS)

    Rehani, M; Samei, E; Morgan, W; Goske, M; Shore, R

    2014-01-01

    There are controversies surrounding radiation effects in human population in the range of radiation doses encountered by patients resulting from one to several CT scans. While it is understandable why the effects from low levels of diagnostic radiation are controversial, the situation is complicated by the media which may distort the known facts. There is need to understand the state of science regarding low-level radiation effects and also to understand how to communicate the potential risk with patients, the public and media. This session will seek to come to a consensus in order to speak with one voice to the media and the public. This session will review radiation effects known so far from a variety of exposed groups since the nuclear holocaust, provide clarification where effects are certain and where they are not, at what level extrapolation is the only way and at what level there is weak but agreeable acceptance. We will depict where and why there is agreement among organizations responsible for studying radiation effects, and how to deal with situations where effects are uncertain. Specific focus on radiation effects in children will be provided.Finally, the session will attempt to bridge the communication gap from the science to how to be an effective communicator with patients, parents, and media about ionizing radiation. Learning Objectives: To have a clear understanding about certainties and uncertainties of radiation effects at the level of a few CT scans To understand the results and limitations from 3 major pediatric CT scientific studies on childhood exposures published recently. To understand successful strategies used in risk communication

  11. MO-C-18C-01: Radiation Risks at Level of Few CT Scans: How Real?- Science to Practice

    Energy Technology Data Exchange (ETDEWEB)

    Rehani, M [International Atomic Energy Agency, Vienna (Austria); Samei, E [Duke University Medical Center, Durham, NC (United States); Morgan, W [Pacific Northwest National Laboratory, Richland, WA (United States); Goske, M [Cincinnati Childrens Hospital, Cincinnati, OH (United States); Shore, R

    2014-06-15

    There are controversies surrounding radiation effects in human population in the range of radiation doses encountered by patients resulting from one to several CT scans. While it is understandable why the effects from low levels of diagnostic radiation are controversial, the situation is complicated by the media which may distort the known facts. There is need to understand the state of science regarding low-level radiation effects and also to understand how to communicate the potential risk with patients, the public and media. This session will seek to come to a consensus in order to speak with one voice to the media and the public. This session will review radiation effects known so far from a variety of exposed groups since the nuclear holocaust, provide clarification where effects are certain and where they are not, at what level extrapolation is the only way and at what level there is weak but agreeable acceptance. We will depict where and why there is agreement among organizations responsible for studying radiation effects, and how to deal with situations where effects are uncertain. Specific focus on radiation effects in children will be provided.Finally, the session will attempt to bridge the communication gap from the science to how to be an effective communicator with patients, parents, and media about ionizing radiation. Learning Objectives: To have a clear understanding about certainties and uncertainties of radiation effects at the level of a few CT scans To understand the results and limitations from 3 major pediatric CT scientific studies on childhood exposures published recently. To understand successful strategies used in risk communication.

  12. Design and operational considerations of United States commercial nea-surface low-level radioactive waste disposal facilities

    International Nuclear Information System (INIS)

    Birk, Sandra M.

    1997-01-01

    Low-level radioactive waste disposal standards and techniques in the United States have evolved significantly since the early 1960's. Six commercial LLW disposal facilities(Barnwell, Richland, Ward Valley, Sierra Blanca, Wake County and Boyd County) operated and proposed between 1962 and 1997. This report summarizes each site's design and operational considerations for near-surface disposal of low-level radioactive waste. These new standards and mitigating efforts at closed facilities (Sheffield, Maxey Flats, Beatty and West Valley) have helped to ensure that the public has been safely protected from LLW. 15 refs

  13. Sensitivity analysis for near-surface disposal in argillaceous media using NAMMU-HYROCOIN Level 3-Test case 1

    International Nuclear Information System (INIS)

    Miller, D.R.; Paige, R.W.

    1988-07-01

    HYDROCOIN is an international project for comparing groundwater flow models and modelling strategies. Level 3 of the project concerns the application of groundwater flow models to repository performance assessment with emphasis on the treatment of sensitivity and uncertainty in models and data. Level 3, test case 1 concerns sensitivity analysis of the groundwater flow around a radioactive waste repository situated in a near surface argillaceous formation. Work on this test case has been carried out by Harwell and will be reported in full in the near future. This report presents the results obtained using the computer program NAMMU. (author)

  14. An acceleration of the characteristics by a space-angle two-level method using surface discontinuity factors

    Energy Technology Data Exchange (ETDEWEB)

    Grassi, G. [Commissariat a l' Energie Atomique, CEA de Saclay, DM2S/SERMA/LENR, 91191, Gif-sur-Yvette (France)

    2006-07-01

    We present a non-linear space-angle two-level acceleration scheme for the method of the characteristics (MOC). To the fine level on which the MOC transport calculation is performed, we associate a more coarsely discretized phase space in which a low-order problem is solved as an acceleration step. Cross sections on the coarse level are obtained by a flux-volume homogenisation technique, which entails the non-linearity of the acceleration. Discontinuity factors per surface are introduced as additional degrees of freedom on the coarse level in order to ensure the equivalence of the heterogeneous and the homogenised problem. After each fine transport iteration, a low-order transport problem is iteratively solved on the homogenised grid. The solution of this problem is then used to correct the angular moments of the flux resulting from the previous free transport sweep. Numerical tests for a given benchmark have been performed. Results are discussed. (authors)

  15. An acceleration of the characteristics by a space-angle two-level method using surface discontinuity factors

    International Nuclear Information System (INIS)

    Grassi, G.

    2006-01-01

    We present a non-linear space-angle two-level acceleration scheme for the method of the characteristics (MOC). To the fine level on which the MOC transport calculation is performed, we associate a more coarsely discretized phase space in which a low-order problem is solved as an acceleration step. Cross sections on the coarse level are obtained by a flux-volume homogenisation technique, which entails the non-linearity of the acceleration. Discontinuity factors per surface are introduced as additional degrees of freedom on the coarse level in order to ensure the equivalence of the heterogeneous and the homogenised problem. After each fine transport iteration, a low-order transport problem is iteratively solved on the homogenised grid. The solution of this problem is then used to correct the angular moments of the flux resulting from the previous free transport sweep. Numerical tests for a given benchmark have been performed. Results are discussed. (authors)

  16. Created mangrove wetlands store belowground carbon and surface elevation change enables them to adjust to sea-level rise

    Science.gov (United States)

    Krauss, Ken W.; Cormier, Nicole; Osland, Michael J.; Kirwan, Matthew L.; Stagg, Camille L.; Nestlerode, Janet A.; Russell, Marc J.; From, Andrew; Spivak, Amanda C.; Dantin, Darrin D.; Harvey, James E.; Almario, Alejandro E.

    2017-01-01

    Mangrove wetlands provide ecosystem services for millions of people, most prominently by providing storm protection, food and fodder. Mangrove wetlands are also valuable ecosystems for promoting carbon (C) sequestration and storage. However, loss of mangrove wetlands and these ecosystem services are a global concern, prompting the restoration and creation of mangrove wetlands as a potential solution. Here, we investigate soil surface elevation change, and its components, in created mangrove wetlands over a 25 year developmental gradient. All created mangrove wetlands were exceeding current relative sea-level rise rates (2.6 mm yr−1), with surface elevation change of 4.2–11.0 mm yr−1 compared with 1.5–7.2 mm yr−1 for nearby reference mangroves. While mangrove wetlands store C persistently in roots/soils, storage capacity is most valuable if maintained with future sea-level rise. Through empirical modeling, we discovered that properly designed creation projects may not only yield enhanced C storage, but also can facilitate wetland persistence perennially under current rates of sea-level rise and, for most sites, for over a century with projected medium accelerations in sea-level rise (IPCC RCP 6.0). Only the fastest projected accelerations in sea-level rise (IPCC RCP 8.5) led to widespread submergence and potential loss of stored C for created mangrove wetlands before 2100.

  17. Created mangrove wetlands store belowground carbon and surface elevation change enables them to adjust to sea-level rise.

    Science.gov (United States)

    Krauss, Ken W; Cormier, Nicole; Osland, Michael J; Kirwan, Matthew L; Stagg, Camille L; Nestlerode, Janet A; Russell, Marc J; From, Andrew S; Spivak, Amanda C; Dantin, Darrin D; Harvey, James E; Almario, Alejandro E

    2017-04-21

    Mangrove wetlands provide ecosystem services for millions of people, most prominently by providing storm protection, food and fodder. Mangrove wetlands are also valuable ecosystems for promoting carbon (C) sequestration and storage. However, loss of mangrove wetlands and these ecosystem services are a global concern, prompting the restoration and creation of mangrove wetlands as a potential solution. Here, we investigate soil surface elevation change, and its components, in created mangrove wetlands over a 25 year developmental gradient. All created mangrove wetlands were exceeding current relative sea-level rise rates (2.6 mm yr -1 ), with surface elevation change of 4.2-11.0 mm yr -1 compared with 1.5-7.2 mm yr -1 for nearby reference mangroves. While mangrove wetlands store C persistently in roots/soils, storage capacity is most valuable if maintained with future sea-level rise. Through empirical modeling, we discovered that properly designed creation projects may not only yield enhanced C storage, but also can facilitate wetland persistence perennially under current rates of sea-level rise and, for most sites, for over a century with projected medium accelerations in sea-level rise (IPCC RCP 6.0). Only the fastest projected accelerations in sea-level rise (IPCC RCP 8.5) led to widespread submergence and potential loss of stored C for created mangrove wetlands before 2100.

  18. Analysing the impact of reflectance distributions and well geometries on vertical surface daylight levels in atria for overcast skies

    Energy Technology Data Exchange (ETDEWEB)

    Du, Jiangtao; Sharples, Steve [School of Architecture, University of Sheffield, Crookesmoor Building, Conduit Road, Sheffield S10 1FL (United Kingdom)

    2010-07-15

    This study investigated the impacts of different diffuse reflectance distributions and well geometries on vertical daylight factors and vertical internally reflected components in atria. Two forms of reflectance distribution patterns of wall surface were examined: horizontal and vertical reflectance band variation. The square atrium models studied have a broader WI range of 0.25-2.0, which represent shallow, medium and high atria. Radiance, a powerful package based on backward ray tracing technique, was used for the simulations of vertical daylight levels. The results show that different reflectance distributions of square atrium walls do have an impact on the vertical daylight factors and vertical internally reflected components under overcast sky condition. The impact relates to the orientation of the band with different reflectance distributions on the wall. Compared with the vertical band surface, the horizontal band surface has a much more complicated effect. The horizontal distributions of the reflectances significantly affects the vertical daylight levels at the locations more than 30% atrium height on the wall. For an atrium with a height more than 1/2 the width, the effect tends to increase with the increasing well index. The vertical distributions of the reflectance, nevertheless, do not substantially take effect on the vertical daylight levels in atria except for some special reflectance distribution patterns. (author)

  19. Using seismology to raise science awareness in kindergarten and elementary levels, with the help of high school students

    Science.gov (United States)

    Rocha, F. L.; Silveira, G. M.; Moreira, G.; Afonso, I. P.; Maciel, B. A. P. C.; Melo, M. O.; Neto, R. P.; Gonçalves, M.; Marques, G.; Hartmann, R. P.

    2014-12-01

    Teaching students, aged from 4 up to 18 years old, is a challenging task. It continuously implies new strategies and new subjects adapted to all of them. This is even more evident, when we have to teach natural-hazards scientific aspects and safe attitudes toward risk. We often see that most of the high-school students (16 -18 years old) are not motivated for extra-curricular activities implying science and/or behaviours changes. But, they have a very positive response when we give them some responsibility. On top of that, we also realised that young children are quite receptive to the involvement of older students in the school environment Taking this into consideration, our project use the k12 students to prepare scientific activities and subjects, based in questions, which they need to answer themselves. The students need to answer those questions and, only then, adapt and teach the right answers to the different school-levels. With this approach, we challenged the students to solve three questions: How to use a SEP seismometer at school, and its data? How to set up a shaking table? How to introduce waves and vibrations contents to all ages of students? During the project they developed many science skills, and worked in straight cooperation with teachers, the parents association and the seismology research group at Instituto Dom Luíz. As a result, it was possible to reach all school students with the help of the k-12 ones. This is an outcome of the project W-Shake, a Parents-in-Science Initiative to promote the study of seismology and related subjects. This project, supported by the Portuguese "Ciência Viva" program, results from a direct cooperation between the parents association, science school-teachers and the seismology research group at Instituto Dom Luíz.

  20. Contamination problems from glass beaker inner surface in low level Po-210 analysis

    Czech Academy of Sciences Publication Activity Database

    Kameník, Jan; Hölgye, Z.

    2010-01-01

    Roč. 283, č. 2 (2010), s. 493-495 ISSN 0236-5731 Institutional research plan: CEZ:AV0Z10480505 Keywords : Po-210 * Low-level analysis * Contamination Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.777, year: 2010