Recalled first reactions to inhaling nicotine predict the level of physical dependence.

Science.gov (United States)

Wellman, Robert J; DiFranza, Joseph R; O'Loughlin, Jennifer

2014-10-01

The level of physical dependence is a measure of addiction that correlates highly with addiction-associated changes in brain structure. We sought to determine whether age at first inhalation and initial reactions to inhaling nicotine are related to level of physical dependence in early adulthood. Young adults (n=312; mean age=24 years; 51% female) from the Nicotine Dependence in Teens study who had smoked at least once in the preceding three months completed self-report questionnaires in 2011-12. We assessed level of physical dependence with three validated self-report items assessing 'wanting,' 'craving' and 'needing' triggered by nicotine deprivation. Survey items assessed smoking behavior, including age at first inhalation, and recalled first reactions to inhaling nicotine. After adjusting for covariates, experiencing relaxation, heart racing/pounding, rush or "buzz" (OR=1.45; 95% CI: 1.08, 1.94) and dizziness (OR=1.58; 95% CI: 1.15, 2.18) at first nicotine inhalation were associated with an increased odds of being at a higher level of physical dependence in young adulthood; the association for experiencing relaxation (OR=1.78; 95% CI: 1.20, 2.64) and heart racing/pounding (OR=1.51; 95% CI: 1.00, 2.28) persisted after additionally controlling for all other first reactions. Neither age at first inhalation nor unpleasant first reactions predicted level of physical dependence. In accordance with prior research, our findings suggest that smokers who are particularly sensitive to the pleasant, "buzz-related" and generally arousing effects of nicotine may be more likely to attain higher levels of physical dependence. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Ab initio calculation of reaction energies. III. Basis set dependence of relative energies on the FH2 and H2CO potential energy surfaces

International Nuclear Information System (INIS)

Frisch, M.J.; Binkley, J.S.; Schaefer, H.F. III

1984-01-01

The relative energies of the stationary points on the FH 2 and H 2 CO nuclear potential energy surfaces relevant to the hydrogen atom abstraction, H 2 elimination and 1,2-hydrogen shift reactions have been examined using fourth-order Moller--Plesset perturbation theory and a variety of basis sets. The theoretical absolute zero activation energy for the F+H 2 →FH+H reaction is in better agreement with experiment than previous theoretical studies, and part of the disagreement between earlier theoretical calculations and experiment is found to result from the use of assumed rather than calculated zero-point vibrational energies. The fourth-order reaction energy for the elimination of hydrogen from formaldehyde is within 2 kcal mol -1 of the experimental value using the largest basis set considered. The qualitative features of the H 2 CO surface are unchanged by expansion of the basis set beyond the polarized triple-zeta level, but diffuse functions and several sets of polarization functions are found to be necessary for quantitative accuracy in predicted reaction and activation energies. Basis sets and levels of perturbation theory which represent good compromises between computational efficiency and accuracy are recommended

The physical basis of biochemistry the foundations of molecular biophysics

CERN Document Server

Bergethon, Peter R

1998-01-01

The objective of this book is to provide a unifying approach to the study of biophysical chemistry for the advanced undergraduate who has had a year of physics, organic chem­ istry, calculus, and biology. This book began as a revised edition of Biophysical Chemistry: Molecules to Membranes, which Elizabeth Simons and I coauthored. That short volume was written in an attempt to provide a concise text for a one-semester course in biophysical chemistry at the graduate level. The experience of teaching biophysical chemistry to bi­ ologically oriented students over the last decade has made it clear that the subject requires a more fundamental text that unifies the many threads of modem science: physics, chem­ istry, biology, mathematics, and statistics. This book represents that effort. This volume is not a treatment of modem biophysical chemistry with its rich history and many contro­ versies, although a book on that topic is also needed. The Physical Basis of Biochemistry is an introduction to the philosophy...

DESIGNING ALGORITHMS FOR SOLVING PHYSICS PROBLEMS ON THE BASIS OF MIVAR APPROACH

Directory of Open Access Journals (Sweden)

Dmitry Alekseevich Chuvikov

2017-05-01

Full Text Available The paper considers the process of designing algorithms for solving physics problems on the basis of mivar approach. The work also describes general principles of mivar theory. The concepts of parameter, relation and class in mivar space are considered. There are descriptions of properties which every object in Wi!Mi model should have. An experiment in testing capabilities of the Wi!Mi software has been carried out, thus the model has been designed which solves physics problems from year 8 school course in Russia. To conduct the experiment a new version of Wi!Mi 2.1 software has been used. The physics model deals with the following areas: thermal phenomena, electric and electromagnetic phenomena, optical phenomena.

Large sodium water reaction calculations in a LMFBR steam generator

International Nuclear Information System (INIS)

Finck, P.; Lepareux, M.; Schwab, B.; Blanchet, Y.

1986-05-01

The French approach to the analysis of large and violent sodium water reactions is presented. The basis for choosing the Design Basis Accident is discussed. An energetical analysis of the physical phenomena involved stresses the specific needs for computing tools. The feature of these tools are then described, and a validation test is presented. Finally, industrial applications are described. 8 refs

Using Physical Organic Chemistry To Shape the Course of Electrochemical Reactions.

Science.gov (United States)

Moeller, Kevin D

2018-05-09

While organic electrochemistry can look quite different to a chemist not familiar with the technique, the reactions are at their core organic reactions. As such, they are developed and optimized using the same physical organic chemistry principles employed during the development of any other organic reaction. Certainly, the electron transfer that triggers the reactions can require a consideration of new "wrinkles" to those principles, but those considerations are typically minimal relative to the more traditional approaches needed to manipulate the pathways available to the reactive intermediates formed downstream of that electron transfer. In this review, three very different synthetic challenges-the generation and trapping of radical cations, the development of site-selective reactions on microelectrode arrays, and the optimization of current in a paired electrolysis-are used to illustrate this point.

On the implementation of a chain nuclear reaction of thermonuclear fusion on the basis of the p+11B process

Science.gov (United States)

Belyaev, V. S.; Krainov, V. P.; Zagreev, B. V.; Matafonov, A. P.

2015-07-01

Various theoretical and experimental schemes for implementing a thermonuclear reactor on the basis of the p+11B reaction are considered. They include beam collisions, fusion in degenerate plasmas, ignition upon plasma acceleration by ponderomotive forces, and the irradiation of a solid-state target from 11B with a proton beam under conditions of a Coulomb explosion of hydrogen microdrops. The possibility of employing ultra-short high-intensity laser pulses to initiate the p+11B reaction under conditions far from thermodynamic equilibrium is discussed. This and some other weakly radioactive thermonuclear reactions are promising owing to their ecological cleanness—there are virtually no neutrons among fusion products. Nuclear reactions that follow the p+11B reaction may generate high-energy protons, sustaining a chain reaction, and this is an advantage of the p+11B option. The approach used also makes it possible to study nuclear reactions under conditions close to those in the early Universe or in the interior of stars.

Complex Reaction Kinetics in Chemistry: A Unified Picture Suggested by Mechanics in Physics

Directory of Open Access Journals (Sweden)

Elena Agliari

2018-01-01

Full Text Available Complex biochemical pathways can be reduced to chains of elementary reactions, which can be described in terms of chemical kinetics. Among the elementary reactions so far extensively investigated, we recall the Michaelis-Menten and the Hill positive-cooperative kinetics, which apply to molecular binding and are characterized by the absence and the presence, respectively, of cooperative interactions between binding sites. However, there is evidence of reactions displaying a more complex pattern: these follow the positive-cooperative scenario at small substrate concentration, yet negative-cooperative effects emerge as the substrate concentration is increased. Here, we analyze the formal analogy between the mathematical backbone of (classical reaction kinetics in Chemistry and that of (classical mechanics in Physics. We first show that standard cooperative kinetics can be framed in terms of classical mechanics, where the emerging phenomenology can be obtained by applying the principle of least action of classical mechanics. Further, since the saturation function plays in Chemistry the same role played by velocity in Physics, we show that a relativistic scaffold naturally accounts for the kinetics of the above-mentioned complex reactions. The proposed formalism yields to a unique, consistent picture for cooperative-like reactions and to a stronger mathematical control.

Nuclear-level densities in the {sup 49}V and {sup 57}Co nuclei on the basis of evaporated-neutron spectra in (p, n) and (d, n) reactions

Energy Technology Data Exchange (ETDEWEB)

Zhuravlev, B. V., E-mail: zhurav@ippe.ru; Titarenko, N. N. [Leipunsky Institute for Physics and Power Engineering (Russian Federation)

2016-03-15

The spectra of neutrons from the reactions {sup 49}Ti(p, n){sup 49}V and {sup 57}Fe (p, n){sup 57}Co were measured in the range of proton energies between 8 and 11 MeV along with their counterparts from the reactions {sup 48}Ti(d, n){sup 49}V and {sup 56}Fe (d, n){sup 57}Co at the deuteron energies of 2.7 and 3.8 MeV. These measurements were conducted with the aid of a time-of-flight fast-neutron spectrometer on the basis of the EGP-15 pulsed tandem accelerator of the Institute for Physics and Power Engineering (IPPE, Obninsk). An analysis of measured data was performed within the statistical equilibrium and preequilibrium models of nuclear reactions. The respective calculations based on the Hauser–Feshbach formalism of statistical theory were carried out with nuclear-level densities given by the generalized superfluid model of the nucleus, the backshifted Fermi-gas model, and the Gilbert–Cameron composite formula. The nuclear-level densities of {sup 49}V and {sup 57}Co and their energy dependences were determined. The results were discussed together with available experimental data and data recommended by model systematics.

The efficiency of driving chemical reactions by a physical non-equilibrium is kinetically controlled.

Science.gov (United States)

Göppel, Tobias; Palyulin, Vladimir V; Gerland, Ulrich

2016-07-27

An out-of-equilibrium physical environment can drive chemical reactions into thermodynamically unfavorable regimes. Under prebiotic conditions such a coupling between physical and chemical non-equilibria may have enabled the spontaneous emergence of primitive evolutionary processes. Here, we study the coupling efficiency within a theoretical model that is inspired by recent laboratory experiments, but focuses on generic effects arising whenever reactant and product molecules have different transport coefficients in a flow-through system. In our model, the physical non-equilibrium is represented by a drift-diffusion process, which is a valid coarse-grained description for the interplay between thermophoresis and convection, as well as for many other molecular transport processes. As a simple chemical reaction, we consider a reversible dimerization process, which is coupled to the transport process by different drift velocities for monomers and dimers. Within this minimal model, the coupling efficiency between the non-equilibrium transport process and the chemical reaction can be analyzed in all parameter regimes. The analysis shows that the efficiency depends strongly on the Damköhler number, a parameter that measures the relative timescales associated with the transport and reaction kinetics. Our model and results will be useful for a better understanding of the conditions for which non-equilibrium environments can provide a significant driving force for chemical reactions in a prebiotic setting.

Experimental studies of keV energy neutron-induced reactions relevant to astrophysics and nuclear physics

Energy Technology Data Exchange (ETDEWEB)

Shima, T.; Kii, T.; Kikuchi, T.; Okazaki, F.; Kobayashi, T.; Baba, T.; Nagai, Y. [Tokyo Inst. of Tech. (Japan). Faculty of Science; Igashira, M.

1997-03-01

Nuclear reactions induced by keV energy neutrons provide a plenty of informations for studies of both astrophysics and nuclear physics. In this paper we will show our experimental studies of neutron- induced reactions of light nuclei in the keV energy region by means of a pulsed keV neutron beam and high-sensitivity detectors. Also we will discuss astrophysical and nuclear-physical consequences by using the obtained results. (author)

Physical Basis for Interfacial Traction-Separation Models

International Nuclear Information System (INIS)

Neville R. Moody

2002-01-01

Many weapon components contain interfaces between dissimilar materials where cracks can initiate and cause failure. In recent years many researchers in the fracture community have adopted a cohesive zone model for simulating crack propagation (based upon traction-separation relations) Sandia is implementing this model in its ASCI codes. There is, however, one important obstacle to using a cohesive zone modeling approach. At the present time traction-separation relations are chosen in an ad hoc manner. The goal of the present work is to determine a physical basis for Traction-Separation (T-U) relations. This report presents results of a program aimed at determining the dependence of such relations on adhesive and bulk properties. The work focused on epoxy/solid interfaces, although the approach is applicable to a broad range of materials. Asymmetric double cantilevered beam and free surface film nanoindentation fracture toughness tests were used to generate a unique set of data spanning length scales, applied mode mixities, and yield (plastic) zone constraint. The crucial roles of crack tip plastic zone size and interfacial adhesion were defined by varying epoxy layer thickness and using coupling agents or special self-assembled monolayers in preparing the samples. The nature of the yield zone was probed in collaborative experiments run at the Advanced Photon Source. This work provides an understanding of the major phenomena governing polymer/solid interfacial fracture and identifies the essential features that must be incorporated in a T-U based cohesive zone failure model. We believe that models using physically based T-U relations provide a more accurate and widely applicable description of interface cracking than models using ad hoc relations. Furthermore, these T-U relations provide an essential tool for using models to tailor interface properties to meet design needs

Extended differential geometry as a basis for physical field theory

International Nuclear Information System (INIS)

Bruce, M.H.

1984-01-01

An extension of Riemann differential geometry is considered as a broadened uniform basis for physical field theory. The requirements for such a theory are set and interpreted as a generalized Ricci calculus capable of supporting certain physical affine motions and metric constraints. Both tensor and spinor languages are considered and a variational calculus is formulated within the geometry. The dominant emergent feature is the replacement of ordinary derivatives by generalized differential operators involving the usual Christoffel symbols as well as more general connection parameters. Then the Euler-Lagrange equations with constraints may be regarded as a general differential geometry and an action principle is formulated to give equations of motion in terms of generalized momentum operations. A cononical momentum tensor is employed which yields, by a generalized boundary variations of the action a set of conservation laws. The formulation is then applied to such diverse topics as the generalizing of the Dirac equation, the Lorentz and radiation terms for a charged particle, the relativistic rotator, and considerations on a geometric origin for the the Einstein energy density tensor

Need for reaction coordinates to ensure a complete basis set in an adiabatic representation of ion-atom collisions

Science.gov (United States)

Rabli, Djamal; McCarroll, Ronald

2018-02-01

This review surveys the different theoretical approaches, used to describe inelastic and rearrangement processes in collisions involving atoms and ions. For a range of energies from a few meV up to about 1 keV, the adiabatic representation is expected to be valid and under these conditions, inelastic and rearrangement processes take place via a network of avoided crossings of the potential energy curves of the collision system. In general, such avoided crossings are finite in number. The non-adiabatic coupling, due to the breakdown of the Born-Oppenheimer separation of the electronic and nuclear variables, depends on the ratio of the electron mass to the nuclear mass terms in the total Hamiltonian. By limiting terms in the total Hamiltonian correct to first order in the electron to nuclear mass ratio, a system of reaction coordinates is found which allows for a correct description of both inelastic channels. The connection between the use of reaction coordinates in the quantum description and the electron translation factors of the impact parameter approach is established. A major result is that only when reaction coordinates are used, is it possible to introduce the notion of a minimal basis set. Such a set must include all avoided crossings including both radial coupling and long range Coriolis coupling. But, only when reactive coordinates are used, can such a basis set be considered as complete. In particular when the centre of nuclear mass is used as centre of coordinates, rather than the correct reaction coordinates, it is shown that erroneous results are obtained. A few results to illustrate this important point are presented: one concerning a simple two-state Landau-Zener type avoided crossing, the other concerning a network of multiple crossings in a typical electron capture process involving a highly charged ion with a neutral atom.

Physics basis for an axicell design for the end plugs of MFTF-B

International Nuclear Information System (INIS)

Baldwin, D.E.; Logan, B.G.

1982-01-01

The primary motivation for conversion of MFTF-B to an axicell configuration lies in its engineering promise as a reactor geometry based on circular high-magnetic-field coils. In comparing this configuration to the previous A-cell geometry, we find a number of differences that might significantly affect the physics performance. The purpose of the present document is to examine those features and to assess their impact on the performance of the axicell, as compared to the A-cell configuration, for MFTF-B. In so doing, we address only those issues thought to be affected by the change in geometry and refer to the original report Physics Basis for MFTF-B, for discussion of those issues thought not to be affected. In Sec. 1, we summarize these physics issues. In Sec. 2, we describe operating scenarios in the new configuration. In the Appendices, we discuss those physics issues that require more detailed treatment

Measurements of physical properties during transesterification of soybean oil to biodiesel for prediction of reaction progress

International Nuclear Information System (INIS)

Moradi, G.R.; Dehghani, S.; Ghanei, R.

2012-01-01

Highlights: ► Reaction progress in transesterification of soybean oil predicted using physical properties. ► Transesterification performed at 70 °C with Me/oil ratio 12:1 and 5 wt.% of BaO as catalyst. ► Viscosity and refractive index decreases nonlinearly during the progress of transesterification. ► Pour point increases linearly and cloud point increases nonlinearly during progress of reaction. ► Refractive index and pour point recommended for prediction transesterification progress. - Abstract: Biodiesel is a pure, non-toxic, biodegradable, clean-burning fuel and renewable alternative for fossil diesel fuel. In this work, a new method was introduced to determine reaction progress in transesterification of soybean oil to biodiesel by the use of physical property variation during reaction. Quantitative analysis stage for determination fatty acid methyl ester (FAME) which is expensive and time-consuming can be replaced by this method. To develop the method, in the first stage, transesterification of soybean oil at optimum conditions (70 °C with MeOH to oil molar ratio of 12:1 and 5 wt.% of BaO as catalyst) was carried out to determine how conversion and physical properties change with time. Then appropriate functions were fitted on the extracted data and were evaluated by comparison with GC results. Refractive index was selected as good physical property to predict reaction progress.

The physical basis for estimating wave-energy spectra with the radar ocean-wave spectrometer

Science.gov (United States)

Jackson, Frederick C.

1987-01-01

The derivation of the reflectivity modulation spectrum of the sea surface for near-nadir-viewing microwave radars using geometrical optics is described. The equations required for the derivation are presented. The derived reflectivity modulation spectrum provides data on the physical basis of the radar ocean-wave spectrometer measurements of ocean-wave directional spectra.

Collection of human reaction times and supporting health related data for analysis of cognitive and physical performance

Directory of Open Access Journals (Sweden)

Petr Brůha

2018-04-01

Full Text Available Smoking, excessive drinking, overeating and physical inactivity are well-established risk factors decreasing human physical performance. Moreover, epidemiological work has identified modifiable lifestyle factors, such as poor diet and physical and cognitive inactivity that are associated with the risk of reduced cognitive performance. Definition, collection and annotation of human reaction times and suitable health related data and metadata provides researchers with a necessary source for further analysis of human physical and cognitive performance. The collection of human reaction times and supporting health related data was obtained from two groups comprising together 349 people of all ages - the visitors of the Days of Science and Technology 2016 held on the Pilsen central square and members of the Mensa Czech Republic visiting the neuroinformatics lab at the University of West Bohemia. Each provided dataset contains a complete or partial set of data obtained from the following measurements: hands and legs reaction times, color vision, spirometry, electrocardiography, blood pressure, blood glucose, body proportions and flexibility. It also provides a sufficient set of metadata (age, gender and summary of the participant's current life style and health to allow researchers to perform further analysis. This article has two main aims. The first aim is to provide a well annotated collection of human reaction times and health related data that is suitable for further analysis of lifestyle and human cognitive and physical performance. This data collection is complemented with a preliminarily statistical evaluation. The second aim is to present a procedure of efficient acquisition of human reaction times and supporting health related data in non-lab and lab conditions. Keywords: Reaction time, Health related data, Cognitive and physical performance, Chronic disease, Data acquisition, Data collection, Software for data collection

Application of dGNSS in Alpine Ski Racing: Basis for Evaluating Physical Demands and Safety

Science.gov (United States)

Gilgien, Matthias; Kröll, Josef; Spörri, Jörg; Crivelli, Philip; Müller, Erich

2018-01-01

External forces, such as ground reaction force or air drag acting on athletes' bodies in sports, determine the sport-specific demands on athletes' physical fitness. In order to establish appropriate physical conditioning regimes, which adequately prepare athletes for the loads and physical demands occurring in their sports and help reduce the risk of injury, sport-and/or discipline-specific knowledge of the external forces is needed. However, due to methodological shortcomings in biomechanical research, data comprehensively describing the external forces that occur in alpine super-G (SG) and downhill (DH) are so far lacking. Therefore, this study applied new and accurate wearable sensor-based technology to determine the external forces acting on skiers during World Cup (WC) alpine skiing competitions in the disciplines of SG and DH and to compare these with those occurring in giant slalom (GS), for which previous research knowledge exists. External forces were determined using WC forerunners carrying a differential global navigation satellite system (dGNSS). Combining the dGNSS data with a digital terrain model of the snow surface and an air drag model, the magnitudes of ground reaction forces were computed. It was found that the applied methodology may not only be used to track physical demands and loads on athletes, but also to simultaneously investigate safety aspects, such as the effectiveness of speed control through increased air drag and ski–snow friction forces in the respective disciplines. Therefore, the component of the ground reaction force in the direction of travel (ski–snow friction) and air drag force were computed. This study showed that (1) the validity of high-end dGNSS systems allows meaningful investigations such as characterization of physical demands and effectiveness of safety measures in highly dynamic sports; (2) physical demands were substantially different between GS, SG, and DH; and (3) safety-related reduction of skiing speed might

Application of dGNSS in Alpine Ski Racing: Basis for Evaluating Physical Demands and Safety

Directory of Open Access Journals (Sweden)

Matthias Gilgien

2018-03-01

Full Text Available External forces, such as ground reaction force or air drag acting on athletes' bodies in sports, determine the sport-specific demands on athletes' physical fitness. In order to establish appropriate physical conditioning regimes, which adequately prepare athletes for the loads and physical demands occurring in their sports and help reduce the risk of injury, sport-and/or discipline-specific knowledge of the external forces is needed. However, due to methodological shortcomings in biomechanical research, data comprehensively describing the external forces that occur in alpine super-G (SG and downhill (DH are so far lacking. Therefore, this study applied new and accurate wearable sensor-based technology to determine the external forces acting on skiers during World Cup (WC alpine skiing competitions in the disciplines of SG and DH and to compare these with those occurring in giant slalom (GS, for which previous research knowledge exists. External forces were determined using WC forerunners carrying a differential global navigation satellite system (dGNSS. Combining the dGNSS data with a digital terrain model of the snow surface and an air drag model, the magnitudes of ground reaction forces were computed. It was found that the applied methodology may not only be used to track physical demands and loads on athletes, but also to simultaneously investigate safety aspects, such as the effectiveness of speed control through increased air drag and ski–snow friction forces in the respective disciplines. Therefore, the component of the ground reaction force in the direction of travel (ski–snow friction and air drag force were computed. This study showed that (1 the validity of high-end dGNSS systems allows meaningful investigations such as characterization of physical demands and effectiveness of safety measures in highly dynamic sports; (2 physical demands were substantially different between GS, SG, and DH; and (3 safety-related reduction of skiing

Application of dGNSS in Alpine Ski Racing: Basis for Evaluating Physical Demands and Safety.

Science.gov (United States)

Gilgien, Matthias; Kröll, Josef; Spörri, Jörg; Crivelli, Philip; Müller, Erich

2018-01-01

External forces, such as ground reaction force or air drag acting on athletes' bodies in sports, determine the sport-specific demands on athletes' physical fitness. In order to establish appropriate physical conditioning regimes, which adequately prepare athletes for the loads and physical demands occurring in their sports and help reduce the risk of injury, sport-and/or discipline-specific knowledge of the external forces is needed. However, due to methodological shortcomings in biomechanical research, data comprehensively describing the external forces that occur in alpine super-G (SG) and downhill (DH) are so far lacking. Therefore, this study applied new and accurate wearable sensor-based technology to determine the external forces acting on skiers during World Cup (WC) alpine skiing competitions in the disciplines of SG and DH and to compare these with those occurring in giant slalom (GS), for which previous research knowledge exists. External forces were determined using WC forerunners carrying a differential global navigation satellite system (dGNSS). Combining the dGNSS data with a digital terrain model of the snow surface and an air drag model, the magnitudes of ground reaction forces were computed. It was found that the applied methodology may not only be used to track physical demands and loads on athletes, but also to simultaneously investigate safety aspects, such as the effectiveness of speed control through increased air drag and ski-snow friction forces in the respective disciplines. Therefore, the component of the ground reaction force in the direction of travel (ski-snow friction) and air drag force were computed. This study showed that (1) the validity of high-end dGNSS systems allows meaningful investigations such as characterization of physical demands and effectiveness of safety measures in highly dynamic sports; (2) physical demands were substantially different between GS, SG, and DH; and (3) safety-related reduction of skiing speed might be

Physical basis behind achondroplasia, the most common form of human dwarfism.

Science.gov (United States)

He, Lijuan; Horton, William; Hristova, Kalina

2010-09-24

Fibroblast growth factor receptor 3 (FGFR3) is a receptor tyrosine kinase that plays an important role in long bone development. The G380R mutation in FGFR3 transmembrane domain is known as the genetic cause for achondroplasia, the most common form of human dwarfism. Despite many studies, there is no consensus about the exact mechanism underlying the pathology. To gain further understanding into the physical basis behind the disorder, here we measure the activation of wild-type and mutant FGFR3 in mammalian cells using Western blots, and we analyze the activation within the frame of a physical-chemical model describing dimerization, ligand binding, and phosphorylation probabilities within the dimers. The data analysis presented here suggests that the mutation does not increase FGFR3 dimerization, as proposed previously. Instead, FGFR3 activity in achondroplasia is increased due to increased probability for phosphorylation of the unliganded mutant dimers. This finding has implications for the design of targeted molecular treatments for achondroplasia.

Recent progress and new challenges in isospin physics with heavy-ion reactions

Energy Technology Data Exchange (ETDEWEB)

Li Baoan [Department of Physics, Texas A and M University-Commerce, Commerce, TX 75429-3011 (United States)], E-mail: Bao-An_Li@Tamu-Commerce.edu; Chen Liewen [Institute of Theoretical Physics, Shanghai Jiao Tong University, Shanghai 200240 (China)], E-mail: Lwchen@Sjtu.edu.cn; Ko, Che Ming [Cyclotron Institute and Physics Department, Texas A and M University, College Station, TX 77843-3366 (United States)], E-mail: Ko@Comp.tamu.edu

2008-08-15

The ultimate goal of studying isospin physics via heavy-ion reactions with neutron-rich, stable and/or radioactive nuclei is to explore the isospin dependence of in-medium nuclear effective interactions and the equation of state of neutron-rich nuclear matter, particularly the isospin-dependent term in the equation of state, i.e., the density dependence of the symmetry energy. Because of its great importance for understanding many phenomena in both nuclear physics and astrophysics, the study of the density dependence of the nuclear symmetry energy has been the main focus of the intermediate-energy heavy-ion physics community during the last decade, and significant progress has been achieved both experimentally and theoretically. In particular, a number of phenomena or observables have been identified as sensitive probes to the density dependence of nuclear symmetry energy. Experimental studies have confirmed some of these interesting isospin-dependent effects and allowed us to constrain relatively stringently the symmetry energy at sub-saturation densities. The impact of this constrained density dependence of the symmetry energy on the properties of neutron stars have also been studied, and they were found to be very useful for the astrophysical community. With new opportunities provided by the various radioactive beam facilities being constructed around the world, the study of isospin physics is expected to remain one of the forefront research areas in nuclear physics. In this report, we review the major progress achieved during the last decade in isospin physics with heavy ion reactions and discuss future challenges to the most important issues in this field.

Functional Basis for Efficient Physical Layer Classical Control in Quantum Processors

Science.gov (United States)

Ball, Harrison; Nguyen, Trung; Leong, Philip H. W.; Biercuk, Michael J.

2016-12-01

The rapid progress seen in the development of quantum-coherent devices for information processing has motivated serious consideration of quantum computer architecture and organization. One topic which remains open for investigation and optimization relates to the design of the classical-quantum interface, where control operations on individual qubits are applied according to higher-level algorithms; accommodating competing demands on performance and scalability remains a major outstanding challenge. In this work, we present a resource-efficient, scalable framework for the implementation of embedded physical layer classical controllers for quantum-information systems. Design drivers and key functionalities are introduced, leading to the selection of Walsh functions as an effective functional basis for both programing and controller hardware implementation. This approach leverages the simplicity of real-time Walsh-function generation in classical digital hardware, and the fact that a wide variety of physical layer controls, such as dynamic error suppression, are known to fall within the Walsh family. We experimentally implement a real-time field-programmable-gate-array-based Walsh controller producing Walsh timing signals and Walsh-synthesized analog waveforms appropriate for critical tasks in error-resistant quantum control and noise characterization. These demonstrations represent the first step towards a unified framework for the realization of physical layer controls compatible with large-scale quantum-information processing.

Quantum theory of exchange reactions: Use of nonorthogonal bases and coordinates

International Nuclear Information System (INIS)

Stechel, E.B.; Schmalz, T.G.; Light, J.C.

1979-01-01

A general approach to quantum scattering theory of exchange reactions utilizing nonorthogonal (''over-complete'') basis sets and nonorthogonal coordinates is presented. The method is shown to resolve many of the formal and practical difficulties attending earlier theories. Although the inspiration came from the early and accurate work on the collinear H+H 2 reaction by Diestler possible applications include electron transfer processes as well as chemical exchange reactions. The mathematics is formulated in detail and the solution is presented in terms of the R-matrix propagation method preserving all the symmetries of the physical process, i.e., conservation of flux and microscopic reversibility

Symmetry-adapted basis sets automatic generation for problems in chemistry and physics

CERN Document Server

Avery, John Scales; Avery, James Emil

2012-01-01

In theoretical physics, theoretical chemistry and engineering, one often wishes to solve partial differential equations subject to a set of boundary conditions. This gives rise to eigenvalue problems of which some solutions may be very difficult to find. For example, the problem of finding eigenfunctions and eigenvalues for the Hamiltonian of a many-particle system is usually so difficult that it requires approximate methods, the most common of which is expansion of the eigenfunctions in terms of basis functions that obey the boundary conditions of the problem. The computational effort needed

CHILDREN'S EDUCATION IN THE REGULAR NATIONAL BASIS: ASSUMPTIONS AND INTERFACES WITH PHYSICAL EDUCATION

Directory of Open Access Journals (Sweden)

André da Silva Mello

2016-09-01

Full Text Available This paper aims at discussing the Children's Education organization within the Regular Curricular National Basis (BNCC, focusing on the permanencies and advances taking in relation to the precedent documents, and analyzing the presence of Physical Education in Children's Education from the assumptions that guide the Base, in interface with researches about pedagogical experiences with this field of knowledge. To do so, it carries out a documental-bibliographic analysis, using as sources the BNCC, the National Curricular Referential for Children's Education, the National Curricular Guidelines for Children's Education and academic-scientific productions belonging to the Physical Education area that approach Children's Education. In the analysis process, the work establishes categories which allow the interlocution among different sources used in this study. Data analyzed offers indications that the assumption present in the BNCC dialogue, not explicitly, with the movements of the curricular component and with the Physical Education academic-scientific production regarding Children's Education.

Computational Approach to Electron Charge Transfer Reactions

DEFF Research Database (Denmark)

Jónsson, Elvar Örn

-molecular mechanics scheme, and tools to analyse statistical data and generate relative free energies and free energy surfaces. The methodology is applied to several charge transfer species and reactions in chemical environments - chemical in the sense that solvent, counter ions and substrate surfaces are taken...... in to account - which directly influence the reactants and resulting reaction through both physical and chemical interactions. All methods are though general and can be applied to different types of chemistry. First, the basis of the various theoretical tools is presented and applied to several test systems...... and asymmetric charge transfer reactions between several first-row transition metals in water. The results are compared to experiments and rationalised with classical analytic expressions. Shortcomings of the methods are accounted for with clear steps towards improved accuracy. Later the analysis is extended...

Progress in physics basis and its impact on ITER

International Nuclear Information System (INIS)

Shimada, M.; Campbell, D.; Stambaugh, R.; Ide, S.; Kamada, Y.; Leonard, A.; Polevoi, A.; Mukhovatov, V.; Costley, A.E.; Gribov, Y.; Oikawa, T.; Sugihara, M.; Asakura, N.; Donne, A.J.H.; Doyle, E.J.; Federici, G.; Kukushkin, A.S.; Gormezano, C.; Gruber, O.; Houlberg, W.; Lipschultz, B.; Medvedev, S.

2005-01-01

This paper summarises recent progress in the physics basis and its impact on the expected performance of ITER. Significant progress has been made in many outstanding issues and in the development of hybrid and steady state operation scenarios, leading to increased confidence of achieving ITER's goals. Experiments show that tailoring the current profile can improve confinement over the standard H-mode and allow an increase in beta up to the no-wall limit at safety factors ∼ 4. Extrapolation to ITER suggests that at the reduced plasma current of ∼ 12MA, high Q > 10 and long pulse (>1000 s) operation is possible with benign ELMs. Analysis of disruption scenarios has been performed based on guidelines on current quench rates and halo currents, derived from the experimental database. With conservative assumptions, estimated electromagnetic forces on the in-vessel components are below the design target values, confirming the robustness of the ITER design against disruption forces. (author)

Toward a physical basis of attention and self-regulation

Science.gov (United States)

Posner, Michael I.; Rothbart, Mary K.

2009-06-01

The concept of self-regulation is central to the understanding of human development. Self-regulation allows effective socialization and predicts both psychological pathologies and levels of achievement in schools. What has been missing are neural mechanisms to provide understanding of the cellular and molecular basis for self-regulation. We show that self-regulation can be measured during childhood by parental reports and by self-reports of adolescents and adults. These reports are summarized by a higher order factor called effortful control, which reflects perceptions about the ability of a given person to regulate their behavior in accord with cultural norms. Throughout childhood effortful control is related to children's performance in computerized conflict related tasks. Conflict tasks have been shown in neuroimaging studies to activate specific brain networks of executive attention. Several brain areas work together at rest and during cognitive tasks to regulate competing brain activity and thus control resulting behavior. The cellular structure of the anterior cingulate and insula contain cells, unique to humans and higher primates that provide strong links to remote brain areas. During conflict tasks, anterior cingulate activity is correlated with activity in remote sensory and emotional systems, depending upon the information selected for the task. During adolescence the structure and activity of the anterior cingulate has been found to be correlated with self-reports of effortful control. Studies have provided a perspective on how genes and environment act to shape the executive attention network, providing a physical basis for self-regulation. The anterior cingulate is regulated by dopamine. Genes that influence dopamine levels in the CNS have been shown to influence the efficiency of self-regulation. For example, alleles of the COMT gene that influence the efficiency of dopamine transmission are related to the ability to resolve conflict. Humans with

Paterno`-Bu¨chi Reaction as a Demonstration of Chemical Kinetics and Synthetic Photochemistry Using a Light Emitting Diode Apparatus

Science.gov (United States)

Thompson, Matthew P.; Agger, Jonathan; Wong, Lu Shin

2015-01-01

The Paterno`-Bu¨chi photocycloaddition reaction is used as the basis for physical-organic final-year undergraduate laboratory experiments designed to emphasize the multidisciplinary approach to modern-day chemical practice. These reactions are performed using commercially available LED-based light sources, which offer a convenient and safe tool…

The physical basis of thermodynamics with applications to chemistry

CERN Document Server

Richet, Pascal

2001-01-01

Given that thermodynamics books are not a rarity on the market, why would an additional one be useful? The answer is simple: at any level, thermodynamics is usually taught as a somewhat abstruse discipline where many students get lost in a maze of difficult concepts. However, thermodynamics is not as intricate a subject as most people feel. This book fills a niche between elementary textbooks and mathematically oriented treatises, and provides readers with a distinct approach to the subject. As indicated by the title, this book explains thermodynamic phenomena and concepts in physical terms before proceeding to focus on the requisite mathematical aspects. It focuses on the effects of pressure, temperature and chemical composition on thermodynamic properties and places emphasis on rapidly evolving fields such as amorphous materials, metastable phases, numerical simulations of microsystems and high-pressure thermodynamics. Topics like redox reactions are dealt with in less depth, due to the fact that there is a...

On the physical basis of pattern formation in nonlinear systems

International Nuclear Information System (INIS)

Sanduloviciu, M.; Lozneanu, E.; Popescu, S.

2003-01-01

Spatial, respectively spatiotemporal patterns appear in a gaseous conductor (plasma) when an external constraint produces a local gradient of electron kinetic energy. Under such conditions, collective quantum effects related to the spatial separation of the excitation and ionization cross-sections determine the appearance of adjacent opposite space charges. The state of the resulting space charge configuration depends on the self-enhancement process of positive ions production, which destabilizes the system. Thus, a spatial pattern in the form of a stable double layer appears after self-organization when the above gradient is smaller than that for which the double layer transits into a moving phase (spatiotemporal pattern). The proposed explanation, based on investigations performed on self-organization phenomena observed in gaseous conductors, suggests a new possibility to clarify the challenging problems concerning the actual physical basis of pattern formation in semiconductors

Lectures on the basis of physics

International Nuclear Information System (INIS)

Cook, A.

1990-09-01

The paper contains the following three lectures given by Alan Cook at ICTP Trieste in August, 1990: ''Metrology and the Structure of Physics'', ''Why does Mathematical Physics Work?'' and ''Probability, Chaos and the Environment. 9 refs

Stable evaluation methods of neutron-physical characteristics of nuclides on the basis of experimental data

International Nuclear Information System (INIS)

Volkov, N.G.; Kryanev, A.V.

1984-01-01

Technique for obtaining estimations of neutron-physical characteristics of nuclides on the basis of stable estimation methods is set forth. The technique presupposes correction of incorrectly determined errors of measurements and disclosure of systematic errors with their succeeding accountancy. A system of orthogonal polynomials is used as approximating functional dependence. The technique is also generalized at the presence of correlation between measurements

Avian magnetic compass: Its functional properties and physical basis

Directory of Open Access Journals (Sweden)

Roswitha WILTSCHKO, Wolfgang WILTSCHKO

2010-06-01

Full Text Available The avian magnetic compass was analyzed in bird species of three different orders – Passeriforms, Columbiforms and Galliforms – and in three different behavioral contexts, namely migratory orientation, homing and directional conditioning. The respective findings indicate similar functional properties: it is an inclination compass that works only within a functional window around the ambient magnetic field intensity; it tends to be lateralized in favor of the right eye, and it is wavelength-dependent, requiring light from the short-wavelength range of the spectrum. The underlying physical mechanisms have been identified as radical pair processes, spin-chemical reactions in specialized photopigments. The iron-based receptors in the upper beak do not seem to be involved. The existence of the same type of magnetic compass in only very distantly related bird species suggests that it may have been present already in the common ancestors of all modern birds, where it evolved as an all-purpose compass mechanism for orientation within the home range [Current Zoology 56 (3: 265–276, 2010].

Immunologic basis for adverse reactions to radiographic contrast media

Energy Technology Data Exchange (ETDEWEB)

Stejskal, V; Nilsson, R; Grepe, A [Astra Pharmaceuticals AB, Soedertaelje (Sweden). Lab. of Safety Assessment Stockholm Univ. (Sweden). Dept. of Genetic and Cellular Toxicology Stockholm Univ. (Sweden). Wallenberglaboratoriet Danderyds Sjukhus, Danderyd (Sweden). Radiologic Clinic

1990-11-01

The lymphocyte transformation test (LTT) was used to elucidate whether certain side effects induced by radiographic contrast media have an immunologic etiology. Groups studied were: 8 patients who had previously experienced adverse reactions in association with urography, 6 patients who underwent urography without notable side reactions, 17 occupationally exposed nurses, and 9 unexposed controls. The lymphocytes from 2 hypersensitive patients and from 11 nurses exhibited a positive proliferative response to amidotrizoate. Five nurses who had shown a positive response, had a previous history of hypersensitivity reactions when handling contrast media, whereas the remaining 6 were free of symptoms. Amidotrizoatespecific memory cells were absent in patients who underwent urography without signs of hypersensitivity and in 7/9 of unexposed control subjects. Lymphocytes from patients sensitive to amidotrizoate cross-reacted to structurally related ionic contrast media while nonionic contrast agents did not induce proliferation of the lymphocytes. Thus, ionic radiographic contrast agents have antigenic properties in man. Irradiated mixtures of radiographic contrast media and serum proteins were, in general, not effective in inducing an LTT response. (orig.).

Immunologic basis for adverse reactions to radiographic contrast media

International Nuclear Information System (INIS)

Stejskal, V.; Nilsson, R.; Grepe, A.; Stockholm Univ.; Stockholm Univ.; Danderyds Sjukhus, Danderyd

1990-01-01

The lymphocyte transformation test (LTT) was used to elucidate whether certain side effects induced by radiographic contrast media have an immunologic etiology. Groups studied were: 8 patients who had previously experienced adverse reactions in association with urography, 6 patients who underwent urography without notable side reactions, 17 occupationally exposed nurses, and 9 unexposed controls. The lymphocytes from 2 hypersensitive patients and from 11 nurses exhibited a positive proliferative response to amidotrizoate. Five nurses who had shown a positive response, had a previous history of hypersensitivity reactions when handling contrast media, whereas the remaining 6 were free of symptoms. Amidotrizoatespecific memory cells were absent in patients who underwent urography without signs of hypersensitivity and in 7/9 of unexposed control subjects. Lymphocytes from patients sensitive to amidotrizoate cross-reacted to structurally related ionic contrast media while nonionic contrast agents did not induce proliferation of the lymphocytes. Thus, ionic radiographic contrast agents have antigenic properties in man. Irradiated mixtures of radiographic contrast media and serum proteins were, in general, not effective in inducing an LTT response. (orig.)

Formation of positive motivation as the basis of students will qualities’ perfection in physical culture practicing

Directory of Open Access Journals (Sweden)

I.O. Dudnyk

2015-06-01

Full Text Available Purpose: to theoretically substantiate and test experimentally pedagogic conditions of positive motivation’s formation as the basis for students will and physical qualities’ perfection in physical culture practicing. Material: 244 first year students participated in experiment. At the beginning and at the end of experiment levels of manifestation of students’ will and physical qualities were assessed. Results: we have proved successfulness of will training if this process is naturally coincides with formation of positive motivation and perfection of motor fitness. It was found that motivation for physical culture practicing result from different demands: demand in motion, demand in fulfillment of student’s duties and demand in competition functioning. Conclusions: we have offered the following pedagogic conditions: application of game and competition methods: setting of appropriate for students tasks of training; usage of sufficient sport equipment and apparatuses; forcing of students for independent physical culture practicing through system of encouragement.

Establishing design basis threats for the physical protection of nuclear materials and facilities

International Nuclear Information System (INIS)

Chetvergov, S.

2001-01-01

In the area of nuclear energy utilization, the Republic of Kazakhstan follows the standards of international legislation and is a participant of the Nuclear Weapons Non-proliferation Treaty as a country that does not have nuclear weapons. In the framework of this treaty, Kazakhstan provides for the measures to ensure the regime of nonproliferation. The Republic signed the Agreement with the IAEA on the guarantee that was ratified by the Presidential Decree in 1995. Now the Government of the RK is considering the Convention on Physical Protection of Nuclear Materials. Kazakhstan legislation in the area of nuclear energy utilization is represented by a set of laws: the main of them is the Law of the Republic of Kazakhstan 'On the utilization of atomic energy', dated April 14, 1997. According to the Law, the issues of physical protection are regulated by interdepartmental guideline documents. Nuclear science and industry of RK include: Enterprises on uranium mining and processing; Ulba metallurgical plant, manufacturing fuel pellets of uranium dioxide for heat release assemblies of RBMK and WWR reactor types, with the enrichment on U235 1.6-4.4%; Power plant in Aktau for heat and power supply and water desalination, based on fast breeder reactor BN-350; Research reactors of National Nuclear Center: WWR-K - water-water reactor, with 10 MW power, uses highly enriched uranium (up to 36% of U-235); IVG.1M - water-water heterogeneous reactor of vessel type on thermal neutrons, maximum power is 35 MW; IGR - impulse homogeneous graphite reactor on thermal neutrons, with graphite reflector; RA - high temperature gas cooled reactor on thermal neutrons, 0.5 MW power. The establishment of design basis threats for nuclear objects in the Republic of Kazakhstan is an urgent problem because of the developing military-political situation in the region. It is necessary to specify important elements affecting the specific features of the design basis threat: military operations of

Reaction Qualifications Revisited

DEFF Research Database (Denmark)

Lippert-Rasmussen, Kasper

2009-01-01

  When, in a competitive sphere, people are selected on the basis of qualifications only, their chances of acquiring positions of advantage may seem to depend entirely upon their abilities, not discriminatory bias. However, if reaction qualifications - i.e. characteristics which contribute...... to a person's effectiveness by causing a favourable reaction in customers, co-workers etc. (for short: recipients) - are involved, this assumption is false. Building on work by Wertheimer, Mason, and Miller, this paper proposes an account of the reaction qualifications that count, from the point of view...... of merit. Specifically, it preserves symmetry between negative evaluations of antimeritocratic bases of selection and negative evaluations of qualifications rooted in comparable antimeritocratic reactions. So if employers should not select among applicants on the basis of their (the employers') racial...

Isospin dependence of physical observables in Incomplete Fusion reactions at 25 MeV/nucleon

Energy Technology Data Exchange (ETDEWEB)

Lombardo, I., E-mail: ilombardo@lns.infn.i [Dipartimento di Fisica, Universita di Catania, Catania (Italy); INFN Laboratori Nazionali del Sud, Catania (Italy); Agodi, C.; Alba, R. [INFN Laboratori Nazionali del Sud, Catania (Italy); Amorini, F. [INFN, Sezione di Catania, Catania (Italy); Dipartimento di Fisica, Universita di Catania, Catania (Italy); Anzalone, A. [INFN Laboratori Nazionali del Sud, Catania (Italy); Berceanu, I. [Institute for Physics and Nuclear Engineering, Bucharest (Romania); Cardella, G. [INFN, Sezione di Catania, Catania (Italy); Cavallaro, S. [Dipartimento di Fisica, Universita di Catania, Catania (Italy); INFN Laboratori Nazionali del Sud, Catania (Italy); Chatterjee, M.B. [Saha Institute of Nuclear Physics, Kolkata (India); Coniglione, R. [INFN Laboratori Nazionali del Sud, Catania (Italy); DeFilippo, E. [INFN, Sezione di Catania, Catania (Italy); DiPietro, A.; Figuera, P. [INFN Laboratori Nazionali del Sud, Catania (Italy); Geraci, E.; Giuliani, G.; Grassi, L. [Dipartimento di Fisica, Universita di Catania, Catania (Italy); INFN, Sezione di Catania, Catania (Italy); Grzeszczuk, A. [Institute of Physics, University of Silesia, Katowice (Poland); LaGuidara, E. [INFN, Sezione di Catania, Catania (Italy); Centro Siciliano di Fisica Nucleare e Struttura della Materia, Catania (Italy); Lanzalone, G. [INFN Laboratori Nazionali del Sud, Catania (Italy); Libera Universita Kore, Enna (Italy); LeNeindre, N. [LPC Caen, CNRS-IN2P3, ENSICAEN, Universite de Caen, Caen (France)

2010-03-01

Isospin dependence of dynamical and thermodynamical physical quantities observed in the reactions {sup 40}Ca + {sup 40,48}Ca and {sup 40}Ca + {sup 46}Ti at 25 MeV/nucleon has been analyzed by means of the CHIMERA multi-detector.

Toward a Neurobiological Basis for Understanding Learning in University Modeling Instruction Physics Courses

Directory of Open Access Journals (Sweden)

Eric Brewe

2018-05-01

Full Text Available Modeling Instruction (MI for University Physics is a curricular and pedagogical approach to active learning in introductory physics. A basic tenet of science is that it is a model-driven endeavor that involves building models, then validating, deploying, and ultimately revising them in an iterative fashion. MI was developed to provide students a facsimile in the university classroom of this foundational scientific practice. As a curriculum, MI employs conceptual scientific models as the basis for the course content, and thus learning in a MI classroom involves students appropriating scientific models for their own use. Over the last 10 years, substantial evidence has accumulated supporting MI's efficacy, including gains in conceptual understanding, odds of success, attitudes toward learning, self-efficacy, and social networks centered around physics learning. However, we still do not fully understand the mechanisms of how students learn physics and develop mental models of physical phenomena. Herein, we explore the hypothesis that the MI curriculum and pedagogy promotes student engagement via conceptual model building. This emphasis on conceptual model building, in turn, leads to improved knowledge organization and problem solving abilities that manifest as quantifiable functional brain changes that can be assessed with functional magnetic resonance imaging (fMRI. We conducted a neuroeducation study wherein students completed a physics reasoning task while undergoing fMRI scanning before (pre and after (post completing a MI introductory physics course. Preliminary results indicated that performance of the physics reasoning task was linked with increased brain activity notably in lateral prefrontal and parietal cortices that previously have been associated with attention, working memory, and problem solving, and are collectively referred to as the central executive network. Critically, assessment of changes in brain activity during the physics

Physical organic studies of organometallic reactions

Energy Technology Data Exchange (ETDEWEB)

Bergman, Robert G. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States). Dept. of Chemistry

1981-01-01

The mechanisms of reactions of organotransition metal complexes have only begun to be understood in detail during the last ten years. The complementary interaction of techniques and concepts developed earlier in studies of organic reaction mechanisms, with those commonly used in inorganic chetnistry, has played a crucial role in helping to elucidate organor.1etall.ic reaction mechanisms. A few systems in which this interaction has proved especially fruitful are discussed in this article.

Application of path integral method to heavy ion reactions, 1. General formalism

Energy Technology Data Exchange (ETDEWEB)

Fujita, J; Negishi, T [Tokyo Univ. of Education (Japan). Dept. of Physics

1976-03-01

The semiclassical approach for heavy ion reactions has become more and more important in analyzing rapidly accumulating data. The purpose of this paper is to lay a quantum-mechanical foundation of the conventional semiclassical treatments in heavy ion physics by using Feynman's path integral method on the basis of the second paper of Pechukas, and discuss simple consequences of the formalism.

Principles of modern physics

CERN Document Server

Saxena, A K

2014-01-01

Principles of Modern Physics, divided into twenty one chapters, begins with quantum ideas followed by discussions on special relativity, atomic structure, basic quantum mechanics, hydrogen atom (and Schrodinger equation) and periodic table, the three statistical distributions, X-rays, physics of solids, imperfections in crystals, magnetic properties of materials, superconductivity, Zeeman-, Stark- and Paschen Back- effects, Lasers, Nuclear physics (Yukawa's meson theory and various nuclear models), radioactivity and nuclear reactions, nuclear fission, fusion and plasma, particle accelerators and detectors, the universe, Elementary particles (classification, eight fold way and quark model, standard model and fundamental interactions), cosmic rays, deuteron problem in nuclear physics, and cathode ray oscilloscope. NEW TO THE FOURTH EDITION: The CO2 Laser Theory of magnetic moments on the basis of shell model Geological dating Laser Induced fusion and laser fusion reactor. Hawking radiation The cosmological red ...

Cofactors in allergic reactions to food : physical exercise and alcohol are the most important

NARCIS (Netherlands)

Versluis, Astrid; van Os-Medendorp, Harmieke; Kruizinga, Astrid G; Blom, W Marty; Houben, Geert F; Knulst, André C

2016-01-01

INTRODUCTION: Involvement of cofactors, like physical exercise, alcohol consumption and use of several types of medication, are associated with more severe food allergic symptoms. However, there is limited evidence on how often cofactors play a role in food allergic reactions. The study aimed to get

Breakup Reactions and Exclusive Measurements in the 6,7Li+144Sm Systems

International Nuclear Information System (INIS)

Heimann, D. Martinez; Pacheco, A. J.; Arazi, A.; Figueira, J. M.; Negri, A. E.; Capurro, O. A.; Carnelli, P.; Fimiani, L.; Grinberg, P.; Marti, G. V.; Testoni, J. E.; Monteiro, D. S.; Niello, J. O. Fernandez; Marta, H. D.

2009-01-01

The breakup of the projectile-like nuclei in reactions induced by 30 MeV 6 Li and 7 Li beams on a 144 Sm target have been measured through the coincident detection of the in-plane emitted light particles. The primary ion that undergoes breakup has been identified and the physically meaningful variables that characterize the reaction have been obtained on a purely experimental basis. Distributions have been obtained for both the binary emission angle and for the breakup emission angle in the reference frame of the breakup products.

Physics basis for MFTF-B

International Nuclear Information System (INIS)

Baldwin, D.E.; Logan, B.G.; Simonen, T.C.

1980-01-01

The physics overview covers the following topics: (1) classical energetics, (2) single-particle adiabaticity and drift effects, (3) equilibrium considerations, (4) low-frequency stability, (5) microstability of plugs and barriers, and (6) electron axial thermal conduction. Operation scenarios and summaries of initial TMX results are also described

Probabilistic risk assessment for the Los Alamos Meson Physics Facility worst-case design-basis accident

International Nuclear Information System (INIS)

Sharirli, M.; Butner, J.M.; Rand, J.L.; Macek, R.J.; McKinney, S.J.; Roush, M.L.

1992-01-01

This paper presents results from a Los Alamos National Laboratory Engineering and Safety Analysis Group assessment of the worse-case design-basis accident associated with the Clinton P. Anderson Meson Physics Facility (LAMPF)/Weapons Neutron Research (WNR) Facility. The primary goal of the analysis was to quantify the accident sequences that result in personnel radiation exposure in the WNR Experimental Hall following the worst-case design-basis accident, a complete spill of the LAMPF accelerator 1L beam. This study also provides information regarding the roles of hardware systems and operators in these sequences, and insights regarding the areas where improvements can increase facility-operation safety. Results also include confidence ranges to incorporate combined effects of uncertainties in probability estimates and importance measures to determine how variations in individual events affect the frequencies in accident sequences

Formation and physical characteristics of van der Waals molecules, cations, and anions: Estimates of complete basis set values

Czech Academy of Sciences Publication Activity Database

Zahradník, Rudolf; Šroubková, Libuše

2005-01-01

Roč. 104, č. 1 (2005), s. 52-63 ISSN 0020-7608 Institutional research plan: CEZ:AV0Z40400503 Keywords : intermolecular complexes * van der Waals species * ab initio calculations * complete basis set values * estimates Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.192, year: 2005

Chapter 8: Plasma operation and control [Progress in the ITER Physics Basis (PIPB)

International Nuclear Information System (INIS)

Gribov, Y.; Humphreys, D.; Kajiwara, K.; Lazarus, E.A.; Lister, J.B.; Ozeki, T.; Portone, A.; Shimada, M.; Sips, A.C.C.; Wesley, J.C.

2007-01-01

The ITER plasma control system has the same functional scope as the control systems in present tokamaks. These are plasma operation scenario sequencing, plasma basic control (magnetic and kinetic), plasma advanced control (control of RWMs, NTMs, ELMs, error fields, etc) and plasma fast shutdown. This chapter considers only plasma initiation and plasma basic control. This chapter describes the progress achieved in these areas in the tokamak experiments since the ITER Physics Basis (1999 Nucl. Fusion 39 2577) was written and the results of assessment of ITER to provide the plasma initiation and basic control. This assessment was done for the present ITER design (15 MA machine) at a more detailed level than it was done for the ITER design 1998 (21 MA machine) described in the ITER Physics Basis (1999 Nucl. Fusion 39 2577). The experiments on plasma initiation performed in DIII-D and JT-60U, as well as the theoretical studies performed for ITER, have demonstrated that, within specified assumptions on the plasma confinement and the impurity influx, ITER can produce plasma initiation in a low toroidal electric field (0.3 V m -1 ), if it is assisted by about 2 MW of ECRF heating. The plasma basic control includes control of the plasma current, position and shape-the plasma magnetic control, as well as control of other plasma global parameters or their profiles-the plasma performance control. The magnetic control is based on more reliable and simpler models of the control objects than those available at present for the plasma kinetic control. Moreover the real time diagnostics used for the magnetic control in many cases are more precise than those used for the kinetic control. Because of these reasons, the plasma magnetic control was developed for modern tokamaks and assessed for ITER better than the kinetic control. However, significant progress has been achieved in the plasma performance control during the last few years. Although the physics basis of plasma operation

Wealth inequality: The physics basis

Science.gov (United States)

Bejan, A.; Errera, M. R.

2017-03-01

"Inequality" is a common observation about us, as members of society. In this article, we unify physics with economics by showing that the distribution of wealth is related proportionally to the movement of all the streams of a live society. The hierarchical distribution of wealth on the earth happens naturally. Hierarchy is unavoidable, with staying power, and difficult to efface. We illustrate this with two architectures, river basins and the movement of freight. The physical flow architecture that emerges is hierarchical on the surface of the earth and in everything that flows inside the live human bodies, the movement of humans and their belongings, and the engines that drive the movement. The nonuniform distribution of wealth becomes more accentuated as the economy becomes more developed, i.e., as its flow architecture becomes more complex for the purpose of covering smaller and smaller interstices of the overall (fixed) territory. It takes a relatively modest complexity for the nonuniformity in the distribution of wealth to be evident. This theory also predicts the Lorenz-type distribution of income inequality, which was adopted empirically for a century.

Nuclear physics with polarized particles

CERN Document Server

Paetz gen Schieck, Hans

2012-01-01

The measurement of spin-polarization observables in reactions of nuclei and particles is of great utility and advantage when the effects of single-spin sub-states are to be investigated. Indeed, the unpolarized differential cross-section encompasses the averaging over the spin states of the particles, and thus loses details of the interaction process. This introductory text combines, in a single volume, course-based lecture notes on spin physics and on polarized-ion sources with the aim of providing a concise yet self-contained starting point for newcomers to the field, as well as for lecturers in search of suitable material for their courses and seminars. A significant part of the book is devoted to introducing the formal theory-a description of polarization and of nuclear reactions with polarized particles. The remainder of the text describes the physical basis of methods and devices necessary to perform experiments with polarized particles and to measure polarization and polarization effects in nuclear rea...

Physical attraction to reliable, low variability nervous systems: Reaction time variability predicts attractiveness.

Science.gov (United States)

Butler, Emily E; Saville, Christopher W N; Ward, Robert; Ramsey, Richard

2017-01-01

The human face cues a range of important fitness information, which guides mate selection towards desirable others. Given humans' high investment in the central nervous system (CNS), cues to CNS function should be especially important in social selection. We tested if facial attractiveness preferences are sensitive to the reliability of human nervous system function. Several decades of research suggest an operational measure for CNS reliability is reaction time variability, which is measured by standard deviation of reaction times across trials. Across two experiments, we show that low reaction time variability is associated with facial attractiveness. Moreover, variability in performance made a unique contribution to attractiveness judgements above and beyond both physical health and sex-typicality judgements, which have previously been associated with perceptions of attractiveness. In a third experiment, we empirically estimated the distribution of attractiveness preferences expected by chance and show that the size and direction of our results in Experiments 1 and 2 are statistically unlikely without reference to reaction time variability. We conclude that an operating characteristic of the human nervous system, reliability of information processing, is signalled to others through facial appearance. Copyright © 2016 Elsevier B.V. All rights reserved.

The physical basis and future of radiation therapy.

Science.gov (United States)

Bortfeld, T; Jeraj, R

2011-06-01

The remarkable progress in radiation therapy over the last century has been largely due to our ability to more effectively focus and deliver radiation to the tumour target volume. Physics discoveries and technology inventions have been an important driving force behind this progress. However, there is still plenty of room left for future improvements through physics, for example image guidance and four-dimensional motion management and particle therapy, as well as increased efficiency of more compact and cheaper technologies. Bigger challenges lie ahead of physicists in radiation therapy beyond the dose localisation problem, for example in the areas of biological target definition, improved modelling for normal tissues and tumours, advanced multicriteria and robust optimisation, and continuous incorporation of advanced technologies such as molecular imaging. The success of physics in radiation therapy has been based on the continued "fuelling" of the field with new discoveries and inventions from physics research. A key to the success has been the application of the rigorous scientific method. In spite of the importance of physics research for radiation therapy, too few physicists are currently involved in cutting-edge research. The increased emphasis on more "professionalism" in medical physics will tip the situation even more off balance. To prevent this from happening, we argue that medical physics needs more research positions, and more and better academic programmes. Only with more emphasis on medical physics research will the future of radiation therapy and other physics-related medical specialties look as bright as the past, and medical physics will maintain a status as one of the most exciting fields of applied physics.

The physical basis and future of radiation therapy

Science.gov (United States)

Bortfeld, T; Jeraj, R

2011-01-01

The remarkable progress in radiation therapy over the last century has been largely due to our ability to more effectively focus and deliver radiation to the tumour target volume. Physics discoveries and technology inventions have been an important driving force behind this progress. However, there is still plenty of room left for future improvements through physics, for example image guidance and four-dimensional motion management and particle therapy, as well as increased efficiency of more compact and cheaper technologies. Bigger challenges lie ahead of physicists in radiation therapy beyond the dose localisation problem, for example in the areas of biological target definition, improved modelling for normal tissues and tumours, advanced multicriteria and robust optimisation, and continuous incorporation of advanced technologies such as molecular imaging. The success of physics in radiation therapy has been based on the continued “fuelling” of the field with new discoveries and inventions from physics research. A key to the success has been the application of the rigorous scientific method. In spite of the importance of physics research for radiation therapy, too few physicists are currently involved in cutting-edge research. The increased emphasis on more “professionalism” in medical physics will tip the situation even more off balance. To prevent this from happening, we argue that medical physics needs more research positions, and more and better academic programmes. Only with more emphasis on medical physics research will the future of radiation therapy and other physics-related medical specialties look as bright as the past, and medical physics will maintain a status as one of the most exciting fields of applied physics. PMID:21606068

Delayed Reaction: The Tardy Embrace of Physical Organic Chemistry by the German Chemical Community.

Science.gov (United States)

Weininger, Stephen J

2018-02-01

The emergence of physical organic chemistry, which focuses on the mechanisms and structures of organic reactions and molecules using the tools of physical chemistry, was a major development in twentieth-century chemistry. It first flourished in the interwar period, in the UK and then in the US. Germany, by contrast, did not embrace the field until almost a half century later. The great success of classical organic chemistry, especially in synthesis, encouraged indifference to the new field among German chemists, as did their inductivist research philosophy, as enunciated by Walter Hückel's ground-breaking textbook (1931). This author also resisted new concepts and representations, especially those of the American theoretician, Linus Pauling. The arrival of the Nazi regime reinforced such resistance. Postwar conditions initiated a reaction against this conservative, nationalistic attitude, especially in the American Occupation Zone. Exposure to American textbooks and visiting lecturers influenced attitudes of younger chemists. The accompanying shift towards a more explanatory, less hierarchical mode of pedagogy was consonant with larger social and political developments.

Resonant thermonuclear reaction rate

International Nuclear Information System (INIS)

Haubold, H.J.; Mathai, A.M.

1986-01-01

Basic physical principles for the resonant and nonresonant thermonuclear reaction rates are applied to find their standard representations for nuclear astrophysics. Closed-form representations for the resonant reaction rate are derived in terms of Meijer's G-function. Analytic representations of the resonant and nonresonant nuclear reaction rates are compared and the appearance of Meijer's G-function is discussed in physical terms

Effectiveness of health tourism application as the basis of health related recreational technology in primary school pupils’ physical education

Directory of Open Access Journals (Sweden)

V.O. Kashuba

2016-04-01

Full Text Available Purpose: to search effective methods of health tourism application in physical education of primary school age pupils. Матеріал: in the research 40 children participated, who were divided into control (9 boys and 11 girls and experimental (10 boys and 10 girls groups. We registered physical fitness, physical health, adaptation-reserve potentials and psychological state of primary school pupils. Results: specificities of health tourism means’ application as the basis of health-related recreational technology were determined. We found improvement of children’s health by 10%. Besides, we observed prevailing improvement of organism’s resistance to environmental unfavorable factors and indicators of psycho-emotional state. Conclusions: application of health tourism means increases organism’s functional potentials, physical health and psycho-emotional state of schoolchildren.

An electromagnetic basis for inertia and gravitation: What are the implications for 21st century physics and technology?

International Nuclear Information System (INIS)

Haisch, Bernhard; Rueda, Alfonso

1998-01-01

The basis of most modern technology is the manipulation of electromagnetic phenomena. Haisch, Rueda and Puthoff (1994a) published a controversial but substantive formulation of a concept proposing an explanation of inertia of matter as an electromagnetic phenomenon originating in the zero-point field (ZPF) of the quantum vacuum. This suggests that Newton's equation of motion can be derived from Maxwell's equations of electrodynamics, in that inertial mass is postulated to be not an intrinsic property of matter but rather a kind of electromagnetic drag force (which temporarily is a place holder for a more general quantum vacuum reaction effect) that proves to be acceleration dependent by virtue of the spectral characteristics of the ZPF. Moreover the principle of equivalence implies that in this view gravitation would also be electromagnetic in origin along the lines proposed by Sakharov (1968). A NASA-funded research effort has been underway at the Lockheed Martin Advanced Technology Center in Palo Alto and at California State University in Long Beach to develop and test these ideas. An effort to generalize the 1994 ZPF-inertia concept into a proper relativistic formulation has been successful. With regard to the goals of the NASA Breakthrough Propulsion Physics Program we can, on the basis of the ZPF-inertia concept, definitively rule out one speculatively hypothesized propulsion mechanism: matter possessing negative inertial mass, a concept originated by Bondi (1957). The existence of this is shown to be logically impossible. On the other hand, the linked ZPF-inertia and ZPF-gravity concepts open the conceptual possibility of manipulation of inertia and gravitation, since both are postulated to be electromagnetic phenomena. Whether this will translate into actual technological potential, especially with respect to spacecraft propulsion and future interstellar travel capability, is an open question. The (possibly comparable) time scale for translation of Einstein

Workshop on the next plan for the study of 'physics of fast neutron reactions and measurements'

International Nuclear Information System (INIS)

1985-03-01

A work shop titled ''Physics of fast neutron reaction and measurements'' was held on 25 December 1984, where discussions were made on the new approach and techniques for neutron measurements. The possibilities of experimental tests with AVF cyclotron was also discussed. The followings are the list of papers presented at the work shop (all papers are written in Japanese except for the abstracts). (1) Monoenergetic neutron beam in Tohoku Cyclotron. (2) Spin-dependent response probed in (p,n) and (n,p) reactions. (3) Measurement of D(n,p) 2n reaction and instrumentation for (n,x) reactions in the 40 - 80 MeV region. (4) Two comments related to the neutron reaction. (5) High energy neutron production facilities in the world and a possibility of neutron induced reaction experiments at RCNP. (6) A neutron counter by detection of recoil protons with solid state detectors and development of neutron source by heavy ions. (7) The measurement of neutrons with the recoil detector. (8) Polarization transfer measurements (Py, Dss, Ds 1 , · · ·) with fast neutron beams. (9) Neutron elastic scattering. (10) Neutron capture gamma reaction and effective charge. (11) Comparison between neutron and charged particle induced reactions. (12) Study of giant resonances by fast neutrons. (Aoki, K.)

Reaction path analysis of sodium-water reaction phenomena in support of chemical reaction model development

International Nuclear Information System (INIS)

Kikuchi, Shin; Ohshima, Hiroyuki; Hashimoto, Kenro

2011-01-01

Computational study of the sodium-water reaction at the gas (water) - liquid (sodium) interface has been carried out using ab initio (first-principle) method. A possible reaction channel has been identified for the stepwise OH bond dissociations of a single water molecule. The energetics including the binding energy of a water molecule to the sodium surface, the activation energies of the bond cleavages, and the reaction energies, have been evaluated, and the rate constants of the first and second OH bond-breakings have been compared. The results are used as the basis for constructing the chemical reaction model used in a multi-dimensional sodium-water reaction code, SERAPHIM, being developed by JAEA toward the safety assessment of the steam generator (SG) in a sodium-cooled fast reactor (SFR). (author)

The physical basis of bacterial quorum communication

CERN Document Server

2015-01-01

This book aims to educate physical scientists and quantitatively-oriented biologists on the application of physical experimentation and analysis, together with appropriate modeling, to understanding and interpreting microbial chemical communication and especially quorum sensing (QS). Quorum sensing describes a chemical communication behavior that is nearly universal among bacteria. Individual cells release a diffusible small molecule (an autoinducer) into their environment. A high concentration of this autoinducer serves as a signal of high population density, triggering new patterns of gene expression throughout the population. However QS is often much more complex than simple census-taking. Many QS bacteria produce and detect multiple autoinducers, which generate quorum signal cross talk with each other and with other bacterial species. QS gene regulatory networks operate in physically complex environments and respond to a range of inputs in addition to autoinducer signals. While many individual QS systems ...

KIT multi-physics tools for the analysis of design and beyond design basis accidents of light water reactors

International Nuclear Information System (INIS)

Sanchez, Victor Hugo; Miassoedov, Alexei; Steinbrueck, M.; Tromm, W.

2016-01-01

This paper describes the KIT numerical simulation tools under extension and validation for the analysis of design and beyond design basis accidents (DBA) of Light Water Reactors (LWR). The description of the complex thermal hydraulic, neutron kinetics and chemo-physical phenomena going on during off-normal conditions requires the development of multi-physics and multi-scale simulations tools which are fostered by the rapid increase in computer power nowadays. The KIT numerical tools for DBA and beyond DBA are validated using experimental data of KIT or from abroad. The developments, extensions, coupling approaches and validation work performed at KIT are shortly outlined and discussed in this paper.

KIT multi-physics tools for the analysis of design and beyond design basis accidents of light water reactors

Energy Technology Data Exchange (ETDEWEB)

Sanchez, Victor Hugo; Miassoedov, Alexei; Steinbrueck, M.; Tromm, W. [Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen (Germany)

2016-05-15

This paper describes the KIT numerical simulation tools under extension and validation for the analysis of design and beyond design basis accidents (DBA) of Light Water Reactors (LWR). The description of the complex thermal hydraulic, neutron kinetics and chemo-physical phenomena going on during off-normal conditions requires the development of multi-physics and multi-scale simulations tools which are fostered by the rapid increase in computer power nowadays. The KIT numerical tools for DBA and beyond DBA are validated using experimental data of KIT or from abroad. The developments, extensions, coupling approaches and validation work performed at KIT are shortly outlined and discussed in this paper.

Variationally optimal selection of slow coordinates and reaction coordinates in macromolecular systems

Science.gov (United States)

Noe, Frank

To efficiently simulate and generate understanding from simulations of complex macromolecular systems, the concept of slow collective coordinates or reaction coordinates is of fundamental importance. Here we will introduce variational approaches to approximate the slow coordinates and the reaction coordinates between selected end-states given MD simulations of the macromolecular system and a (possibly large) basis set of candidate coordinates. We will then discuss how to select physically intuitive order paremeters that are good surrogates of this variationally optimal result. These result can be used in order to construct Markov state models or other models of the stationary and kinetics properties, in order to parametrize low-dimensional / coarse-grained model of the dynamics. Deutsche Forschungsgemeinschaft, European Research Council.

The general theory of multistage geminate reactions of isolated pairs of reactants. III. Two-stage reversible dissociation in geminate reaction A + A↔C↔B + B

Energy Technology Data Exchange (ETDEWEB)

Kipriyanov, Alexey A.; Kipriyanov, Alexander A.; Doktorov, Alexander B. [Voevodsky Institute of Chemical Kinetics and Combustion, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia and Novosibirsk State University, Novosibirsk 630090 (Russian Federation)

2016-04-14

Specific two-stage reversible reaction A + A↔C↔B + B of the decay of species C reactants by two independent transition channels is considered on the basis of the general theory of multistage reactions of isolated pairs of reactants. It is assumed that at the initial instant of time, the reacting system contains only reactants C. The employed general approach has made it possible to consider, in the general case, the inhomogeneous initial distribution of reactants, and avoid application of model concepts of a reaction system structure (i.e., of the structure of reactants and their molecular mobility). Slowing of multistage reaction kinetics as compared to the kinetics of elementary stages is established and physically interpreted. To test approximations (point approximation) used to develop a universal kinetic law, a widely employed specific model of spherical particles with isotropic reactivity diffusing in solution is applied. With this particular model as an example, ultimate kinetics of chemical conversion of reactants is investigated. The question concerning the depths of chemical transformation at which long-term asymptotes are reached is studied.

Confirmation Of Super Heavy Element Production In 48Ca Induced Fusion Reactions A Handshake Of Physics And Chemistry For Element 112

International Nuclear Information System (INIS)

Hofmann, S.; Ackermann, D.; Burkhard, H. G.; Heinz, S.; Hessberger, F. P.; Khuyagbaatar, J.; Kindler, B.; Kojouharov, I.; Lommel, B.; Mann, R.; Muenzenberg, G.; Schoett, H. J.; Sulignano, B.; Antalic, S.; Saro, S.; Streicher, B.; Venhart, M.; Yeremin, A. V.; Comas, V. F.; Heredia, J. A.

2008-01-01

The production of 283 112 in 48 Ca induced nuclear reactions was investigated using physical and chemical separation techniques. In the reaction 48 Ca on 238 U, four events were registered at the SHIP velocity filter. The mean atomic mass of the evaporation residues (EVR)

The physics basis for ignition using indirect-drive targets on the National Ignition Facility

International Nuclear Information System (INIS)

Lindl, John D.; Amendt, Peter; Berger, Richard L.; Glendinning, S. Gail; Glenzer, Siegfried H.; Haan, Steven W.; Kauffman, Robert L.; Landen, Otto L.; Suter, Laurence J.

2004-01-01

drive temperature, drive symmetry, and hydrodynamic instability. This paper starts with a review of the NIF target designs that have formed the motivation for the goals of the target physics program. Following that are theoretical and experimental results from Nova and Omega relevant to the requirements of those targets. Some elements of this work were covered in a 1995 review of indirect-drive [J. D. Lindl, 'Development of the indirect-drive approach to inertial confinement fusion and the target physics basis for ignition and gain', Phys. Plasmas 2, 3933 (1995)]. In order to present as complete a picture as possible of the research that has been carried out on indirect drive, key elements of that earlier review are also covered here, along with a review of work carried out since 1995

Laser thermal effect on silicon nitride ceramic based on thermo-chemical reaction with temperature-dependent thermo-physical parameters

International Nuclear Information System (INIS)

Pan, A.F.; Wang, W.J.; Mei, X.S.; Wang, K.D.; Zhao, W.Q.; Li, T.Q.

2016-01-01

Highlights: • A two-dimensional thermo-chemical reaction model is creatively built. • Thermal conductivity and heat capacity of β-Si_3N_4 are computed accurately. • The appropriate thermo-chemical reaction rate is fitted and reaction element length is set to assure the constringency. • The deepest ablated position was not the center of the ablated area due to plasma absorption. • The simulation results demonstrate the thermo-chemical process cant be simplified to be physical phase transition. - Abstract: In this study, a two-dimensional thermo-chemical reaction model with temperature-dependent thermo-physical parameters on Si_3N_4 with 10 ns laser was developed to investigate the ablated size, volume and surface morphology after single pulse. For model parameters, thermal conductivity and heat capacity of β-Si_3N_4 were obtained from first-principles calculations. Thermal-chemical reaction rate was fitted by collision theory, and then, reaction element length was deduced using the relationship between reaction rate and temperature distribution. Furthermore, plasma absorption related to energy loss was approximated as a function of electron concentration in Si_3N_4. It turned out that theoretical ablated volume and radius increased and then remained constant with increasing laser energy, and the maximum ablated depth was not in the center of the ablated zone. Moreover, the surface maximum temperature of Si_3N_4 was verified to be above 3000 K within pulse duration, and it was much higher than its thermal decomposition temperature of 1800 K, which indicated that Si_3N_4 was not ablated directly above the thermal decomposition temperature. Meanwhile, the single pulse ablation of Si_3N_4 was performed at different powers using a TEM_0_0 10 ns pulse Nd:YAG laser to validate the model. The model showed a satisfactory consistence between the experimental data and numerical predictions, presenting a new modeling technology that may significantly increase the

Hypernuclear physics with the (π+, K+) reaction

International Nuclear Information System (INIS)

Millener, D.J.; Chrien, R.E.

1989-01-01

The study of hypernuclei affords unique insights into the nature of hadronic forces beyond those obtainable from ordinary nuclear physics research. A hypernucleus consists of one or more hyperons bound to a nuclear core. In the SU(3) classification, Λ,Σ, and Ξ hyperons occupy the same octet representation of spin-parity 1/2 + baryons as the neutron and proton, the familiar constituents of ordinary nuclei. The Λ and Σ possess strangeness S = -1 and isotopic spin I = 0, 1, respectively, while the Ξ has S = -2, I = 1/2. In the underlying quark picture, the Λ and Σ have the flavor structure s(ud) I=0, 1 , compared to the combination uud for the proton. The strange quark, s, carries the strangeness quantum number S = -1, which makes it distinguishable from the S = 0 u and d quarks. The lowest-lying hyperon is the Λ, with a mass of 1,115.6 MeV/c 2 , some 177 MeV/c 2 heavier than the proton. The study of the behavior of a hyperon embedded in the nuclear medium, through the theoretical analysis of level spectra, sheds light on the nature of the hyperon-nucleon (YN) effective interaction, i.e. on the role of the strange quark in strong interactions. This paper investigates the (π + , K + ) reactions that produce hypernuclei. 32 refs., 5 figs., 2 tabs

Engineering reactors for catalytic reactions

Indian Academy of Sciences (India)

Extensive studies have been conducted to establish sound basis for design and engineering of reactors for practising such catalytic reactions and for realizing improvements in reactor performance. In this article, application of recent (and not so recent) developments in engineering reactors for catalytic reactions is ...

Analysis of insulation material deterioration under the LOCA simulated environment on the basis of reaction kinetics

Energy Technology Data Exchange (ETDEWEB)

Okada, Sohei; Kusama, Yasuo; Ito, Masayuki; Yagi, Toshiaki; Yoshikawa, Masato (Japan Atomic Energy Research Inst., Takasaki, Gunma. Takasaki Radiation Chemistry Research Establishment)

1982-12-01

In the type test of the electric cables installed in reactor containment vessels, it is considerably difficult to perform the testing over a year once in a while to simulate the accidental environment containing radiation and high temperature steam. Two requirements which seem to be more realistic as compared with the above mentioned testing method are inconsistent with each other. To solve this problem, a general rule of deterioration or the expression by an equation is necessary, which enables the extrapolation to show that a short term testing stands on the safety side. The authors have tried to numerically analyze the change of mechanical characteristics of ethylene-propylene rubber (EPR) and Hypalon which are, important as the materials for PH cables (fire-retardant, EP rubber-insulated, chlorosulfonated polyethylene-sheathed cable), in a complex environment of radiation, steam and chemical spray simulating PWR LOCA conditions. In this report, a method is proposed to analyze and estimate the properties by the regression analysis technique on the basis of reaction kinetics, and the analyzed results are described in the order of experiment, analysis method and the results and consideration. The deterioration of the elongation P = e/esub(o) of EPR and Hypalon in the above described complex environment can be represented by the equation - dP/dt = KPsup(n). The exponent n varied in the cases when air is contained or not in that environment, suggesting that the different reactions are dominant in both conditions, respectively. For EPR, n was close to 2 if air was not contained and close to 1 if air was contained in the system.

The general theory of multistage geminate reactions of isolated pairs of reactants. III. Two-stage reversible dissociation in geminate reaction A + A ↔ C ↔ B + B.

Science.gov (United States)

Kipriyanov, Alexey A; Kipriyanov, Alexander A; Doktorov, Alexander B

2016-04-14

Specific two-stage reversible reaction A + A ↔ C ↔ B + B of the decay of species C reactants by two independent transition channels is considered on the basis of the general theory of multistage reactions of isolated pairs of reactants. It is assumed that at the initial instant of time, the reacting system contains only reactants C. The employed general approach has made it possible to consider, in the general case, the inhomogeneous initial distribution of reactants, and avoid application of model concepts of a reaction system structure (i.e., of the structure of reactants and their molecular mobility). Slowing of multistage reaction kinetics as compared to the kinetics of elementary stages is established and physically interpreted. To test approximations (point approximation) used to develop a universal kinetic law, a widely employed specific model of spherical particles with isotropic reactivity diffusing in solution is applied. With this particular model as an example, ultimate kinetics of chemical conversion of reactants is investigated. The question concerning the depths of chemical transformation at which long-term asymptotes are reached is studied.

Measurement of the Quasifree pn → dη Reaction near Threshold

International Nuclear Information System (INIS)

Calen, H.; Dyring, J.; Fransson, K.; Gustafsson, L.; Haeggstroem, S.; Hoeistad, B.; Johansson, A.; Johansson, T.; Kullander, S.; Moertsell, A.; Ruber, R.J.; Schuberth, U.; Zlomanczuk, J.; Ekstroem, C.; Kilian, K.; Oelert, W.; Renken, V.; Sefzick, T.; Bondar, A.; Kuzmin, A.; Shwartz, B.; Sidorov, V.; Sukhanov, A.; Kupsc, A.; Marciniewski, P.; Stepaniak, J.; Dunin, V.; Morosov, B.; Povtorejko, A.; Sukhanov, A.; Zernov, A.; Zabierowski, J.; Wilhelmi, Z.

1997-01-01

The quasifree p+n→d+η reaction cross section has been measured in the near-threshold region using deuterium from an internal cluster-jet target and 1350 MeV protons in the CELSIUS storage ring of the The Svedberg Laboratory, Uppsala. The energy dependence of the cross section is extracted by exploiting the Fermi momentum of the target neutron and reconstructing the kinematics on an event-by-event basis. The data cover center of mass excess energies from 16 to 113 MeV. copyright 1997 The American Physical Society

Providing the physical basis of SCS curve number method and its proportionality relationship from Richards' equation

Science.gov (United States)

Hooshyar, M.; Wang, D.

2016-12-01

The empirical proportionality relationship, which indicates that the ratio of cumulative surface runoff and infiltration to their corresponding potentials are equal, is the basis of the extensively used Soil Conservation Service Curve Number (SCS-CN) method. The objective of this paper is to provide the physical basis of the SCS-CN method and its proportionality hypothesis from the infiltration excess runoff generation perspective. To achieve this purpose, an analytical solution of Richards' equation is derived for ponded infiltration in shallow water table environment under the following boundary conditions: 1) the soil is saturated at the land surface; and 2) there is a no-flux boundary which moves downward. The solution is established based on the assumptions of negligible gravitational effect, constant soil water diffusivity, and hydrostatic soil moisture profile between the no-flux boundary and water table. Based on the derived analytical solution, the proportionality hypothesis is a reasonable approximation for rainfall partitioning at the early stage of ponded infiltration in areas with a shallow water table for coarse textured soils.

Investigating Students' Reasoning about Acid-Base Reactions

Science.gov (United States)

Cooper, Melanie M.; Kouyoumdjian, Hovig; Underwood, Sonia M.

2016-01-01

Acid-base chemistry is central to a wide range of reactions. If students are able to understand how and why acid-base reactions occur, it should provide a basis for reasoning about a host of other reactions. Here, we report the development of a method to characterize student reasoning about acid-base reactions based on their description of…

Development of D-allose sensor on the basis of three strategic enzyme reactions.

Science.gov (United States)

Miyanishi, Nobumitsu; Nakakita, Shin-Ichi; Sumiyoshi, Wataru; Okuma, Hirokazu; Izumori, Ken; Hirabayashi, Jun

2010-09-15

Rare sugars are defined as monosaccharides and their derivatives that rarely exist in nature, according to the International Society of Rare Sugars. D-Allose (3-epi d-glucose) is one of the rare sugars, for which various physiological activities have recently been found, with increasing attention to its applications to bio-industry. Until now, however, there is no convenient method of measuring these sugars in a specific manner. For detecting D-allose, three consecutive enzyme reactions were devised by fabricating of a reaction batch chamber packed with L-rhamnose isomerase (LRI), D-tagatose 3-epimerase (DTE) and a screen-printed electrode, on which D-fructose dehydrogenase (DFDH) was immobilized. To obtain a substantial sensing system, extensive experimental parameters were optimized. These included the concentration of photo-crosslinkable poly (vinyl alcohol) bearing stilbazolium groups (PVA-SbQ), reaction ratios, and temperature of the batch chamber. By adopting the three consecutive enzyme reactions, an undesirable reverse reaction was minimized. As a result, the developed sensor system exhibited a good linear response on D-allose in the range from 0.1 to 50 mM (r(2)=0.998). The system has an apparent advantage over the previous chromatography approach in terms of simplicity and inexpensiveness. Copyright 2010 Elsevier B.V. All rights reserved.

Discussion of the Investigation Method on the Reaction Kinetics of Metallurgical Reaction Engineering

Science.gov (United States)

Du, Ruiling; Wu, Keng; Zhang, Jiazhi; Zhao, Yong

Reaction kinetics of metallurgical physical chemistry which was successfully applied in metallurgy (as ferrous metallurgy, non-ferrous metallurgy) became an important theoretical foundation for subject system of traditional metallurgy. Not only the research methods were very perfect, but also the independent structures and systems of it had been formed. One of the important tasks of metallurgical reaction engineering was the simulation of metallurgical process. And then, the mechanism of reaction process and the conversion time points of different control links should be obtained accurately. Therefore, the research methods and results of reaction kinetics in metallurgical physical chemistry were not very suitable for metallurgical reaction engineering. In order to provide the definite conditions of transmission, reaction kinetics parameters and the conversion time points of different control links for solving the transmission and reaction equations in metallurgical reaction engineering, a new method for researching kinetics mechanisms in metallurgical reaction engineering was proposed, which was named stepwise attempt method. Then the comparison of results between the two methods and the further development of stepwise attempt method were discussed in this paper. As a new research method for reaction kinetics in metallurgical reaction engineering, stepwise attempt method could not only satisfy the development of metallurgical reaction engineering, but also provide necessary guarantees for establishing its independent subject system.

Sodium-concrete reaction model development

International Nuclear Information System (INIS)

Nguyen, D.H.; Muhlestein, L.D.; Postma, A.K.

1982-07-01

Major observations have been formulated after reviewing test results for over 100 sodium-concrete reaction tests. The observations form the basis for developing a mechanistic model to predict the transient behavior of sodium-concrete reactions. The major observations are listed. Mechanisms associated with sodium and water transport to the reaction zone are identified, and represented by appropriate mathematical expressions. The model attempts to explain large-scale, long-term (100 h) test results were sodium-concrete reactions terminated even in the presence of unreacted sodium and concrete

Establishing 'design basis threat' in Norway

International Nuclear Information System (INIS)

Maerli, M.B.; Naadland, E.; Reistad, O.

2002-01-01

Full text: INFCIRC 225 (Rev. 4) assumes that a state's physical protection system should be based on the state's evaluation of the threat, and that this should be reflected in the relevant legislation. Other factors should also be considered, including the state's emergency response capabilities and the existing and relevant measures of the state's system of accounting for and control of nuclear material. A design basis threat developed from an evaluation by the state of the threat of unauthorized removal of nuclear material and of sabotage of nuclear material and nuclear facilities is an essential element of a state's system of physical protection. The state should continuously review the threat, and evaluate the implications of any changes in that threat for the required levels and the methods of physical protection. As part of a national design basis threat assessment, this paper evaluates the risk of nuclear or radiological terrorism and sabotage in Norway. Possible scenarios are presented and plausible consequences are discussed with a view to characterize the risks. The need for more stringent regulatory requirements will be discussed, together with the (positive) impact of improved systems and procedures of physical protection on nuclear emergency planning. Special emphasis is placed on discussing the design basis threat for different scenarios in order to systemize regulatory efforts to update the current legislation, requirement for operators' contingency planning, response efforts and the need for emergency exercises. (author)

Propagation of neutron-reaction uncertainties through multi-physics models of novel LWR's

Directory of Open Access Journals (Sweden)

Hernandez-Solis Augusto

2017-01-01

Full Text Available The novel design of the renewable boiling water reactor (RBWR allows a breeding ratio greater than unity and thus, it aims at providing for a self-sustained fuel cycle. The neutron reactions that compose the different microscopic cross-sections and angular distributions are uncertain, so when they are employed in the determination of the spatial distribution of the neutron flux in a nuclear reactor, a methodology should be employed to account for these associated uncertainties. In this work, the Total Monte Carlo (TMC method is used to propagate the different neutron-reactions (as well as angular distributions covariances that are part of the TENDL-2014 nuclear data (ND library. The main objective is to propagate them through coupled neutronic and thermal-hydraulic models in order to assess the uncertainty of important safety parameters related to multi-physics, such as peak cladding temperature along the axial direction of an RBWR fuel assembly. The objective of this study is to quantify the impact that ND covariances of important nuclides such as U-235, U-238, Pu-239 and the thermal scattering of hydrogen in H2O have in the deterministic safety analysis of novel nuclear reactors designs.

National practices in physical protection of nuclear materials. Regulatory basis

International Nuclear Information System (INIS)

Goltsov, V.Y.

2002-01-01

Full text: The Federal law 'On The Use Of Atomic Energy' containing the section on physical protection of nuclear materials and nuclear facilities was issued in 1995 in Russian Federation. This document became the first federal level document regulating the general requirements to physical protection (PP). The federal PP rules developed on the base of this law by Minatom of Russia and other federal bodies of the Russian Federation were put in force by the government of Russia in 1997. The requirements of the convention on physical protection of nuclear materials (INFCIRC 274) and the modern IAEA recommendations (INFCIRC/225/Rev.4) are taken into account in the PP rules. Besides, while developing the PP rules the other countries' experience in this sphere has been studied and taken into account. The PP rules are action-obligatory for all juridical persons dealing with nuclear activity and also for those who are coordinating and monitoring this activity. Nuclear activity without physical protection ensured in accordance with PP rules requirements is prohibited. The requirements of PP Rules are stronger than the IAEA recommendations. The PP rules are establishing: physical protection objectives; federal executive bodies and organizations functions an implementation of physical protection; categorization of nuclear materials; requirements for nuclear materials physical protection as during use and storage as during transportation; main goals of state supervision and ministry level control for physical protection; notification order about the facts of unauthorized actions regarding nuclear materials and facilities. Besides the above mentioned documents, there were put in force president decrees, federal laws and regulations in the field of: counteraction to nuclear terrorism; interactions in physical protection systems; military and ministerial on-site guard activities; information protection. By the initiative of Minatom of Russia the corrections were put into the

Physic basis of electromagnetic induction low

Directory of Open Access Journals (Sweden)

V.J. Kutkovetskyy

2015-03-01

Full Text Available The statement on the macro level of EMF dependence on change in magnetic flux in time wrong reflects the physical phenomenon of electromagnetic induction low by Faraday, because EMF can be inducted if the magnetic flux of the circuit does not change. Changing magnetic flux of the circuit when the electromotive force arises is only a result of crossing the magnetic field lines by conductor and is an exception, which applies only to certain classes of electric machines.

Conference on Computing in High Energy Physics 21 - 25 Sep 1992

CERN Document Server

CERN. Geneva

1992-09-21

The nuclear predicament or nuclear option - Synopsis of three lectures : 1- The physical basis of nuclear technology. Physics of fission. Chain reaction in reactors and weapons. Fission fragments. Separration of isotopes. Radiochemistry. 2- Nuclear reactors with slow and fast neutrons. Power, size, fuel and waste. Plutonium production. Dose rate, shielding and health hazard. The lessons of Chernobyl. 3- Nuclear weapons. Types, energy, blast and fallout. Fusion and hydrogen bombs. What to do with nuclear weapons when you cannot use them? Testing. Nonmilittary use. Can we get rid of the nuclear weapon? Nuclear proliferation. Is there a nuclear future?

Physical Chemistry Chemical Kinetics and Reaction Mechanism

CERN Document Server

Trimm, Harold H

2011-01-01

Physical chemistry covers diverse topics, from biochemistry to materials properties to the development of quantum computers. Physical chemistry applies physics and math to problems that interest chemists, biologists, and engineers. Physical chemists use theoretical constructs and mathematical computations to understand chemical properties and describe the behavior of molecular and condensed matter. Their work involves manipulations of data as well as materials. Physical chemistry entails extensive work with sophisticated instrumentation and equipment as well as state-of-the-art computers. This

πN inelastic reaction index, 1977

International Nuclear Information System (INIS)

Kawaguchi, Masaaki; Kichimi, Hiromichi; Oyanagi, Yoshio; Sugahara, Ryuhei; Takahashi, Kasuke.

1977-08-01

This report prepared by the KEK-PDG (Particle Data Group of the National Laboratory for High Energy Physics, Ibaraki, Japan) is a document compilation which covers 298 literatures dealing with πN inelastic reactions which were published in either of the following journals in the years of 1974, 1975 and 1976: Nuovo Cimento, Nuovo Cimento Letters, Nuclear Physics, Physics Letters, Physical Review, Physical Review Letters, Soviet Journal of Nuclear Physics and JETP Letters. Five indices are also given to facilitate the use of this compilation. Almost all the pages of this report is devoted to the listing of the five indices (accelerator, detector, reaction, beam momentum, and data description indices). In the appendix, some abbreviations for accelerators, detectors, institutions, and particles are listed. The descriptors for reaction data, and for particle properties, and beam momentum designations are also listed in the appendix. (Aoki, K.)

TD-S-HF single determinantal reaction theory and the description of many-body processes, including fission

International Nuclear Information System (INIS)

Griffin, J.J.; Lichtner, P.C.; Dworzecka, M.; Kan, K.K.

1979-01-01

The restrictions implied for the time dependent many-body reaction theory by the (TDHF) single determinantal assumption are explored by constructive analysis. A restructured TD-S-HF reaction theory is modelled, not after the initial-value form of the Schroedinger reaction theory, but after the (fully equivalent) S-matrix form, under the conditions that only self-consistent TDHF solutions occur in the theory, every wave function obeys the fundamental statistical interpretation of quantum mechanics, and the theory reduces to the exact Schroedinger theory for exact solutions which are single determinantal. All of these conditions can be accomodated provided that the theory is interpreted on a time-averaged basis, i.e., physical constants of the Schroedinger theory which are time-dependent in the TDHF theory, are interpreted in TD-S-HF in terms of their time averaged values. The resulting reaction theory, although formulated heuristically, prescribes a well defined and unambiguous calculational program which, although somewhat more demanding technically than the conventional initial-value TDHF method, is nevertheless more consonant with first principles, structurally and mechanistically. For its physical predictions do not depend upon the precise location of the distant measuring apparatus, and are in no way influenced by the spurious cross channel correlations which arise whenever the description of many reaction channels is imposed upon one single-determinantal solution. For nuclear structure physics, the TDHF-eigenfunctions provide the first plausible description of exact eigenstates in the time-dependent framework; moreover, they are unencumbered by any restriction to small amplitudes. 14 references

Single-particle basis and translational invariance in microscopic nuclear calculations

International Nuclear Information System (INIS)

Ehfros, V.D.

1977-01-01

The approach to the few-body problem is considered which allows to use the simple single-particle basis without violation of the translation invariance. A method is proposed to solve the nuclear reaction problems in the single-particle basis. The method satisfies the Pauli principle and the translation invariance. Calculation of the matrix elements of operators is treated

Non extensive corrections to stellar nuclear reactions rate

Energy Technology Data Exchange (ETDEWEB)

Assuncao, M. [Universidade Federal de Sao Paulo (DCET/UNIFESP), Diadema, SP (Brazil). Dept. de Ciencias Exatas e da Terra; Silveira, F.E.M. [Universidade Federal do ABC, Santo Andre, SP (Brazil). Centro de Ciencias Naturais e Humanas; Lima, J.A.S. [Universidade de Sao Paulo (IAG/USP), SP (Brazil). Inst. de Astronomia, Geofisica e Ciencias Atmosfericas

2010-07-01

Full text: Stellar nucleosynthesis is widely accepted as the basic mechanism for creation of chemical elements in the Universe. In particular, nuclear reactions occurring in the Sun are recognized as responsible for its energy generation. The problem of to determine the energy generation mechanism in stars was firstly attacked by Gamow in the framework of his quantum mechanical theory of potential barrier penetration. According to that approach, the reactions rate is calculated by averaging the penetration factor over the velocity distribution of the plasma particles. A randomization of that distribution is expected as a consequence of the reactions. However, diffusion processes in the macroscopic environment should balance the resulting particles number depletion. Therefore, matter, energy, and momentum might steadily flow. In other words, a quasi-stationary equilibrium state must be attained. In this work, the potential barrier penetration approach to stellar nuclear reactions rate has been rediscussed with basis on Tsallis nonextensive statistics. The investigation has been restricted to non-resonant reactions, for which the S-factor can be regarded as a constant. It has been found that, within the extended formulation, the nonextensive q-parameter is constrained to a maximum value. Accordingly, the q-energy has been shown to exhibit a minimum. The q-Gamow peak has been derived and, in connection with the usual Gaussian approximation, the corresponding half q-width has been also estimated. Plots of the q-energy, q-Gamow peak and half q-width for some reactions with stellar physics interest have been produced. (author)

Gamow-Teller transitions and neutron-proton-pair transfer reactions

Science.gov (United States)

Van Isacker, P.; Macchiavelli, A. O.

2018-05-01

We propose a schematic model of nucleons moving in spin-orbit partner levels, j = l ± 1/2, to explain Gamow-Teller and two-nucleon transfer data in N = Z nuclei above 40Ca. Use of the LS coupling scheme provides a more transparent approach to interpret the structure and reaction data. We apply the model to the analysis of charge-exchange, 42Ca(3He,t)42Sc, and np-transfer, 40Ca(3He,p)42Sc, reactions data to define the elementary modes of excitation in terms of both isovector and isoscalar pairs, whose properties can be determined by adjusting the parameters of the model (spin-orbit splitting, isovector pairing strength and quadrupole matrix element) to the available data. The overall agreement with experiment suggests that the approach captures the main physics ingredients and provides the basis for a boson approximation that can be extended to heavier nuclei. Our analysis also reveals that the SU(4)-symmetry limit is not realized in 42Sc.

Reaction Qualifications Revisited

DEFF Research Database (Denmark)

Lippert-Rasmussen, Kasper

2009-01-01

to a person's effectiveness by causing a favourable reaction in customers, co-workers etc. (for short: recipients) - are involved, this assumption is false. Building on work by Wertheimer, Mason, and Miller, this paper proposes an account of the reaction qualifications that count, from the point of view...... preferences, recipients should not respond to the applicant actually hired on the basis of their (the recipients') racial preferences. My account decomposes the meritocratic ideal into four separate norms, one of which applies to recipients rather than to selectors. Finally, it defends the view that reaction...... qualifications based on antimeritocratic reactions, while not unproblematic, are not entirely irrelevant from the point of view of merit. Notably, selectors need not discount them when no one - including the targets of the objectionable preferences - is unfairly disadvantaged. Because not all problematic...

Transport description of damped nuclear reactions

International Nuclear Information System (INIS)

Randrup, J.

1984-01-01

This lecture series is concerned with the transport description of damped nuclear reactions. Part 1 is an elementary introduction to the general transport theory of nuclear dynamics. It can be read without any special knowledge of the field, although basic quantum mechanics is required for the formal derivation of the general expressions for the transport coefficients. The results can also be used in a wider context than the present one. Part 2 gives the student an up-to-date orientation about recent progress in the understanding of the angular-momentum variables in damped reactions. The emphasis is here on the qualitative understanding of the physics rather than the, at times somewhat tedious, formal derivations. More detailed presentations are due to be published soon. By necessity entire topics have been omitted. For example, no discussion is given of the calculation of the form factors, and the several instructive applications of the theory to transport of mass and change are not covered at all. For these topics they refer to the literature. It is hoped that the present notes provide a sufficient basis to make the literature on the subject accessible to the student

Soft tissue deformation modelling through neural dynamics-based reaction-diffusion mechanics.

Science.gov (United States)

Zhang, Jinao; Zhong, Yongmin; Gu, Chengfan

2018-05-30

Soft tissue deformation modelling forms the basis of development of surgical simulation, surgical planning and robotic-assisted minimally invasive surgery. This paper presents a new methodology for modelling of soft tissue deformation based on reaction-diffusion mechanics via neural dynamics. The potential energy stored in soft tissues due to a mechanical load to deform tissues away from their rest state is treated as the equivalent transmembrane potential energy, and it is distributed in the tissue masses in the manner of reaction-diffusion propagation of nonlinear electrical waves. The reaction-diffusion propagation of mechanical potential energy and nonrigid mechanics of motion are combined to model soft tissue deformation and its dynamics, both of which are further formulated as the dynamics of cellular neural networks to achieve real-time computational performance. The proposed methodology is implemented with a haptic device for interactive soft tissue deformation with force feedback. Experimental results demonstrate that the proposed methodology exhibits nonlinear force-displacement relationship for nonlinear soft tissue deformation. Homogeneous, anisotropic and heterogeneous soft tissue material properties can be modelled through the inherent physical properties of mass points. Graphical abstract Soft tissue deformation modelling with haptic feedback via neural dynamics-based reaction-diffusion mechanics.

Reaction rate distribution measurement and the core performance evaluation in the prototype FBR Monju

Energy Technology Data Exchange (ETDEWEB)

Usami, S.; Suzuoki, Z.; Deshimaru, T. [Monju Construction Office, Japan Nuclear Cycle Development Institute, Fukui-ken (Japan); Nakashima, F. [Tsuruga head Office, Japan Nuclear Cycle Development Institute, Fukui-ken (Japan)

2001-07-01

Monju is a prototype fast breeder reactor designed to have an output of 280 MW (714 MWt), fueled with mixed oxides of plutonium and uranium and cooled by liquid sodium. The principal data on plant design and performance are shown in Table 1. Monju attained initial criticality in April 1994 and the reactor physics tests were carried out from May through November 1994. The reaction rate distribution measurement by the foil activation method was one of these tests and was carried out in order to verify the core performance and to contribute to the development of the core design methods. On the basis of the reaction rate measurement data, the Monju initial core breeding ratio and the power distribution were evaluated. (author)

Reaction rate distribution measurement and the core performance evaluation in the prototype FBR Monju

International Nuclear Information System (INIS)

Usami, S.; Suzuoki, Z.; Deshimaru, T.; Nakashima, F.

2001-01-01

Monju is a prototype fast breeder reactor designed to have an output of 280 MW (714 MWt), fueled with mixed oxides of plutonium and uranium and cooled by liquid sodium. The principal data on plant design and performance are shown in Table 1. Monju attained initial criticality in April 1994 and the reactor physics tests were carried out from May through November 1994. The reaction rate distribution measurement by the foil activation method was one of these tests and was carried out in order to verify the core performance and to contribute to the development of the core design methods. On the basis of the reaction rate measurement data, the Monju initial core breeding ratio and the power distribution were evaluated. (author)

Improved predictions of nuclear reaction rates for astrophysics applications with the TALYS reaction code

International Nuclear Information System (INIS)

Goriely, S.; Hilaire, S.; Koning, A.J.

2008-01-01

Nuclear reaction rates for astrophysics applications are traditionally determined on the basis of Hauser-Feshbach reaction codes, like MOST. These codes use simplified schemes to calculate the capture reaction cross section on a given target nucleus, not only in its ground state but also on the different thermally populated states of the stellar plasma at a given temperature. Such schemes include a number of approximations that have never been tested, such as an approximate width fluctuation correction, the neglect of delayed particle emission during the electromagnetic decay cascade or the absence of the pre-equilibrium contribution at increasing incident energies. New developments have been brought to the reaction code TALYS to estimate the Maxwellian-averaged reaction rates of astrophysics relevance. These new developments give us the possibility to calculate with an improved accuracy the reaction cross sections and the corresponding astrophysics rates. The TALYS predictions for the thermonuclear rates of astrophysics relevance are presented and compared with those obtained with the MOST code on the basis of the same nuclear ingredients for nuclear structure properties, optical model potential, nuclear level densities and γ-ray strength. It is shown that, in particular, the pre-equilibrium process significantly influences the astrophysics rates of exotic neutron-rich nuclei. The reciprocity theorem traditionally used in astrophysics to determine photo-rates is also shown no to be valid for exotic nuclei. The predictions obtained with different nuclear inputs are also analyzed to provide an estimate of the theoretical uncertainties still affecting the reaction rate prediction far away from the experimentally known regions. (authors)

Explore the reaction mechanism of the Maillard reaction: a density functional theory study.

Science.gov (United States)

Ren, Ge-Rui; Zhao, Li-Jiang; Sun, Qiang; Xie, Hu-Jun; Lei, Qun-Fang; Fang, Wen-Jun

2015-05-01

The mechanism of Maillard reaction has been investigated by means of density functional theory calculations in the gaseous phase and aqueous solution. The Maillard reaction is a cascade of consecutive and parallel reaction. In the present model system study, glucose and glycine were taken as the initial reactants. On the basis of previous experimental results, the mechanisms of Maillard reaction have been proposed, and the possibility for the formation of different compounds have been evaluated through calculating the relative energy changes for different steps of reaction under different pH conditions. Our calculations reveal that the TS3 in Amadori rearrangement reaction is the rate-determining step of Maillard reaction with the activation barriers of about 66.7 and 68.8 kcal mol(-1) in the gaseous phase and aqueous solution, respectively. The calculation results are in good agreement with previous studies and could provide insights into the reaction mechanism of Maillard reaction, since experimental evaluation of the role of intermediates in the Maillard reaction is quite complicated.

Molecular basis of sperm capacitation acrosome reaction and interaction with eggs

International Nuclear Information System (INIS)

Sheikhnejad, G.

1985-01-01

A phospholipase C (PLC) which can hydrolyze 14 C-phosphatidylcholine was purified from bull seminal plasma. This PLC has an optimum at pH 7.2 and its PI was about 5.0. The enzyme was inhibited by EDTA, Cd 2+ , Pb 2+ , Ni 2+ , Fe 2+ , and Zn 2+ . PLC consists of two subunits one 69,000 and the other 55,000 daltons. The purified PLC was examined for induction of capacitation and acrosome reaction of guinea pig spermatozoa. Sperm were examined for the acrosome reaction 10 min after addition of 3.4 mM Ca 2+ . Fifty percent of the sperm underwent the acrosome reaction while the control had less than 5% acrosome reacted sperm. The antiserum to the inneracrosomal membrane isolated from sperm was labeled with FITC conjugated goat anti-guinea pig IgG. The conjugated antibody was used to localize sperm antigens. The antigens located on the IAM were only fluoresced when rabbit sperm were treated with methanol and/or MgCl 2 . Therefore anti-IAM antibody did not bind to the sperm plasma membrane. In vivo capacitated rabbit sperm were incubated with anti-IAM antibody (intact IgG and F(ab') 2 fragments) for 30 min prior to addition of rabbit eggs. After 24 h the eggs were examined for cleavage. The control eggs were fertilized (90%) while the antibody completely inhibited the fertilization of ova in vitro. The eggs incubated with antibody prior to the addition of sperm were still fertilizable. Thus, anti-IAM did not have any noticeable effect on the eggs. It was also shown that antibody inhibited fertilization of zona-free rabbit eggs in vitro as well

The Oblique Basis Method from an Engineering Point of View

International Nuclear Information System (INIS)

Gueorguiev, V G

2012-01-01

The oblique basis method is reviewed from engineering point of view related to vibration and control theory. Examples are used to demonstrate and relate the oblique basis in nuclear physics to the equivalent mathematical problems in vibration theory. The mathematical techniques, such as principal coordinates and root locus, used by vibration and control theory engineers are shown to be relevant to the Richardson - Gaudin pairing-like problems in nuclear physics.

Technical basis for the ITER-FEAT outline design

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-11-01

This ITER EDA Documentation Series issue summarizes the results of the ITER Engineering Design Activities on the technical basis for the ITER-FEAT outline design. This issue also comprises some physical analysis activities as well as structure and goals of the Physics Expert Group activities.

Technical basis for the ITER-FEAT outline design

International Nuclear Information System (INIS)

2000-01-01

This ITER EDA Documentation Series issue summarizes the results of the ITER Engineering Design Activities on the technical basis for the ITER-FEAT outline design. This issue also comprises some physical analysis activities as well as structure and goals of the Physics Expert Group activities

Modeling interfacial glass-water reactions: recent advances and current limitations

International Nuclear Information System (INIS)

Pierce, Eric M.; Frugier, Pierre; Criscenti, Louise J.; Kwon, Kideok D.; Kerisit, Sebastien N.

2014-01-01

Describing the reactions that occur at the glass-water interface and control the development of the altered layer constitutes one of the main scientific challenges impeding existing models from providing accurate radionuclide release estimates. Radionuclide release estimates are a critical component of the safety basis for geologic repositories. The altered layer (i.e., amorphous hydrated surface layer and crystalline reaction products) represents a complex region, both physically and chemically, sandwiched between two distinct boundaries-pristine glass surface at the inner most interface and aqueous solution at the outer most interface. Computational models, spanning different length and timescales, are currently being developed to improve our understanding of this complex and dynamic process with the goal of accurately describing the mesoscale changes that occur as the system evolves. These modeling approaches include geochemical simulations (i.e., classical reaction path simulations and glass reactivity in allowance for alteration layer simulations), Monte Carlo simulations, and molecular dynamics methods. Discussed in this manuscript are the advances and limitations of each modeling approach placed in the context of the glass-water reaction and how collectively these approaches provide insights into the mechanisms that control the formation and evolution of altered layers. New results are presented as examples of each approach. (authors)

ITER technical basis

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-01-01

Following on from the Final Report of the EDA(DS/21), and the summary of the ITER Final Design report(DS/22), the technical basis gives further details of the design of ITER. It is in two parts. The first, the Plant Design specification, summarises the main constraints on the plant design and operation from the viewpoint of engineering and physics assumptions, compliance with safety regulations, and siting requirements and assumptions. The second, the Plant Description Document, describes the physics performance and engineering characteristics of the plant design, illustrates the potential operational consequences foe the locality of a generic site, gives the construction, commissioning, exploitation and decommissioning schedule, and reports the estimated lifetime costing based on data from the industry of the EDA parties.

ITER technical basis

International Nuclear Information System (INIS)

2002-01-01

Following on from the Final Report of the EDA(DS/21), and the summary of the ITER Final Design report(DS/22), the technical basis gives further details of the design of ITER. It is in two parts. The first, the Plant Design specification, summarises the main constraints on the plant design and operation from the viewpoint of engineering and physics assumptions, compliance with safety regulations, and siting requirements and assumptions. The second, the Plant Description Document, describes the physics performance and engineering characteristics of the plant design, illustrates the potential operational consequences foe the locality of a generic site, gives the construction, commissioning, exploitation and decommissioning schedule, and reports the estimated lifetime costing based on data from the industry of the EDA parties

Experimental and numerical reaction analysis on sodium-water chemical reaction field

International Nuclear Information System (INIS)

Deguchi, Yoshihiro; Takata, Takashi; Yamaguchi, Akira; Kikuchi, Shin; Ohshima, Hiroyuki

2015-01-01

In a sodium-cooled fast reactor (SFR), liquid sodium is used as a heat transfer fluid because of its excellent heat transport capability. On the other hand, it has strong chemical reactivity with water vapor. One of the design basis accidents of the SFR is the water leakage into the liquid sodium flow by a breach of heat transfer tubes. This process ends up damages on the heat transport equipment in the SFR. Therefore, the study on sodium-water chemical reactions is of paramount importance for security reasons. This study aims to clarify the sodium-water reaction mechanisms using an elementary reaction analysis. A quasi one-dimensional flame model is applied to a sodium-water counter-flow reaction field. The analysis contains 25 elementary reactions, which consist of 17 H_2-O_2 and 8 Na-H_2O reactions. Temperature and species concentrations in the counter-flow reaction field were measured using laser diagnostics such as LIF and CARS. The main reaction in the experimental conditions is Na+H_2O → NaOH+H and OH is produced by H_2O+H → H_2+OH. It is demonstrated that the reaction model in this study well explains the structure of the sodium-water counter-flow diffusion flame. (author)

Encouraging conceptual change: the use of bridging analogies in the teaching of action reaction forces and the `at rest' condition in physics

Science.gov (United States)

Bryce, Tom; MacMillan, Kenneth

2005-06-01

The qualitative study described in this paper examined the effectiveness of bridging analogies intended to bring about conceptual change as part of a constructivist approach to teaching about action reaction forces in the ‘at rest’ condition in physics. Twenty-one 15-year-old students were involved in the investigation with subgroups previously exposed to different information regarding forces, weight and the accepted cause of the reaction force, in simple physical arrangements, including objects on tables. In-depth ‘think aloud’ interviews were used to track each student’s conceptual status as they worked with bridging analogies and transcript coding was carried out using open and axial coding (as in a grounded theory methodology). The findings showed that the bridging analogies were effective in engaging students with the idea of action reaction forces; students were adept in mapping each of the analogies to the target concept and using them to generate and refine their causal theories for the reaction force. There was evidence to suggest that, for some students, bridging analogies were more effective in bringing about conceptual change than didactic teaching. Their use extends beyond illustrative purposes and supports the development of meta-cognitive skills.

Impact of physical exercise on reaction time in patients with Parkinson's disease-data from the Berlin BIG Study.

Science.gov (United States)

Ebersbach, Georg; Ebersbach, Almut; Gandor, Florin; Wegner, Brigitte; Wissel, Jörg; Kupsch, Andreas

2014-05-01

To determine whether physical activity may affect cognitive performance in patients with Parkinson's disease by measuring reaction times in patients participating in the Berlin BIG study. Randomized controlled trial, rater-blinded. Ambulatory care. Patients with mild to moderate Parkinson's disease (N=60) were randomly allocated to 3 treatment arms. Outcome was measured at the termination of training and at follow-up 16 weeks after baseline in 58 patients (completers). Patients received 16 hours of individual Lee Silverman Voice Treatment-BIG training (BIG; duration of treatment, 4wk), 16 hours of group training with Nordic Walking (WALK; duration of treatment, 8wk), or nonsupervised domestic exercise (HOME; duration of instruction, 1hr). Cued reaction time (cRT) and noncued reaction time (nRT). Differences between treatment groups in improvement in reaction times from baseline to intermediate and baseline to follow-up assessments were observed for cRT but not for nRT. Pairwise t test comparisons revealed differences in change in cRT at both measurements between BIG and HOME groups (intermediate: -52ms; 95% confidence interval [CI], -84/-20; P=.002; follow-up: 55ms; CI, -105/-6; P=.030) and between WALK and HOME groups (intermediate: -61ms; CI, -120/-2; P=.042; follow-up: -78ms; CI, -136/-20; P=.010). There was no difference between BIG and WALK groups (intermediate: 9ms; CI, -49/67; P=.742; follow-up: 23ms; CI, -27/72; P=.361). Supervised physical exercise with Lee Silverman Voice Treatment-BIG or Nordic Walking is associated with improvement in cognitive aspects of movement preparation. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Climate refugia: The physical, hydrologic and disturbance basis

Science.gov (United States)

Holden, Z. A.; Maneta, M. P.; Forthofer, J.

2015-12-01

Projected changes in global climate and associated shifts in vegetation have increased interest in understanding species persistence at local scales. We examine the climatic and physical factors that could mediate changes in the distribution of vegetation in regions of complex topography. Using massive networks of low-cost temperature and humidity sensors, we developed topographically-resolved daily historical gridded temperature data for the US Northern Rockies. We used the WindNinja model to create daily historical wind speed maps across the same domain. Using a spatially distributed ecohydrology model (ECH2O) we examine separately the sensitivity of modeled evapotranspiration and soil moisture to wind, radiation, soil properties, minimum temperature and humidity. A suite of physical factors including lower wind speeds, cold air drainage, solar shading and increased soil depth reduce evapotranspiration and increase late season moisture availability in valley bottoms. Evapotranspiration shows strong sensitivity to spatial variability in surface wind speed, suggesting that sheltering effects from winds may be an important factor contributing to mountain refugia. Fundamental to our understanding of patterns of vegetation change is the role of stand-replacing wildfires, which modify the physical environment and subsequent patterns of species persistence and recruitment. Using satellite-derived maps of burn severity for recent fires in the US Northern Rockies we examined relationships between wind speed, cold air drainage potential and soil depth and the occurrence of unburned and low severity fire. Severe fire is less likely to occur in areas with high cold air drainage potential and low wind speeds, suggesting that sheltered valley bottoms have mediated the severity of recent wildfires. Our finding highlight the complex physical mechanisms by which mountain weather and climate mediate fire-induced vegetation changes in the US Northern Rocky Mountains.

The Physics Basis of ITER Confinement

International Nuclear Information System (INIS)

Wagner, F.

2009-01-01

ITER will be the first fusion reactor and the 50 year old dream of fusion scientists will become reality. The quality of magnetic confinement will decide about the success of ITER, directly in the form of the confinement time and indirectly because it decides about the plasma parameters and the fluxes, which cross the separatrix and have to be handled externally by technical means. This lecture portrays some of the basic principles which govern plasma confinement, uses dimensionless scaling to set the limits for the predictions for ITER, an approach which also shows the limitations of the predictions, and describes briefly the major characteristics and physics behind the H-mode--the preferred confinement regime of ITER.

Compressed modes for variational problems in mathematical physics and compactly supported multiresolution basis for the Laplace operator

Science.gov (United States)

Ozolins, Vidvuds; Lai, Rongjie; Caflisch, Russel; Osher, Stanley

2014-03-01

We will describe a general formalism for obtaining spatially localized (``sparse'') solutions to a class of problems in mathematical physics, which can be recast as variational optimization problems, such as the important case of Schrödinger's equation in quantum mechanics. Sparsity is achieved by adding an L1 regularization term to the variational principle, which is shown to yield solutions with compact support (``compressed modes''). Linear combinations of these modes approximate the eigenvalue spectrum and eigenfunctions in a systematically improvable manner, and the localization properties of compressed modes make them an attractive choice for use with efficient numerical algorithms that scale linearly with the problem size. In addition, we introduce an L1 regularized variational framework for developing a spatially localized basis, compressed plane waves (CPWs), that spans the eigenspace of a differential operator, for instance, the Laplace operator. Our approach generalizes the concept of plane waves to an orthogonal real-space basis with multiresolution capabilities. Supported by NSF Award DMR-1106024 (VO), DOE Contract No. DE-FG02-05ER25710 (RC) and ONR Grant No. N00014-11-1-719 (SO).

The physical and radiobiological basis of the Local Effect Model (LEM) A response to the commentary by R. Katz

CERN Document Server

Scholz, M; The Physics of Quantum Electronics

2004-01-01

The physical and biological basis of our model to calculate the biological effects of charged particles, termed local effect model (LEM), has been recently questioned in a commentary by R. Katz. Major objections were related to the definition of the target size and the use of the term cross section. Here we show that the objections raised against our approach are unjustified and largely based on serious misunderstandings of the conceptual basis of the local effect model. Furthermore, we show that the approach developed by Katz and coworkers itself suffers from exactly those deficiencies, for which Katz criticises our model. The essential conceptual differences between the two models are discussed by means of some illustrative examples, based on a comparison with experimental data. For these examples, the predictions of the LEM model are fully consistent with the experimental data. Contrarily, e.g. for very heavy ions there are significant discrepancies observed for the Katz approach. These discrepancies can b...

A comprehensive survey of nuclear reactions; Panorama des reactions nucleaires

Energy Technology Data Exchange (ETDEWEB)

Cugnon, J. [Liege Univ., IFPA, AGO Dept. (Belgium)

2007-07-01

The various mechanisms of nuclear reactions are surveyed and classified in different regimes, based on the notions of coherent mechanisms and hard versus soft processes. The emphasis is put on the concepts at the basis of the understanding of these regimes and on the elements of nuclear structure which are involved in these different regimes, as well as the on the possibility of extracting this information. Due to lack of space and for pedagogical reasons, the discussion is limited to nucleon-induced and light-ion-induced reactions. However, a few remarks are given concerning some specific probes, such as weakly bound projectiles or neutron-rich nuclei. (author)

Theoretical study of the influence of chemical reactions and physical parameters on the convective dissolution of CO2 in aqueous solutions

Science.gov (United States)

Loodts, Vanessa; Rongy, Laurence; De Wit, Anne

2014-05-01

Subsurface carbon sequestration has emerged as a promising solution to the problem of increasing atmospheric carbon dioxide (CO2) levels. How does the efficiency of such a sequestration process depend on the physical and chemical characteristics of the storage site? This question is emblematic of the need to better understand the dynamics of CO2 in subsurface formations, and in particular, the properties of the convective dissolution of CO2 in the salt water of aquifers. This dissolution is known to improve the safety of the sequestration by reducing the risks of leaks of CO2 to the atmosphere. Buoyancy-driven convection makes this dissolution faster by transporting dissolved CO2 further away from the interface. Indeed, upon injection, the less dense CO2 phase rises above the aqueous layer where it starts to dissolve. The dissolved CO2 increases the density of the aqueous solution, thereby creating a layer of denser CO2-rich solution above less dense solution. This unstable density gradient in the gravity field is at the origin of convection. In this framework, we theoretically investigate the effect of CO2 pressure, salt concentration, temperature, and chemical reactions on the dissolution-driven convection of CO2 in aqueous solutions. On the basis of a linear stability analysis, we assess the stability of the time-dependent density profiles developing when CO2 dissolves in an aqueous layer below it. We predict that increasing CO2 pressure destabilizes the system with regard to buoyancy-driven convection, because it increases the density gradient at the origin of the instability. By contrast, increasing salt concentration or temperature stabilizes the system via effects on CO2 solubility, solutal expansion coefficient, diffusion coefficient and on the viscosity and density of the solution. We also show that a reaction of CO2 with chemical species dissolved in the aqueous solution can either enhance or decrease the amplitude of the convective dissolution compared

Research in theoretical nuclear physics

International Nuclear Information System (INIS)

Udagawa, T.

1993-11-01

This report describes the accomplishments in basic research in nuclear physics carried out by the theoretical nuclear physics group in the Department of Physics at the University of Texas at Austin, during the period of November 1, 1992 to October 31, 1993. The work done covers three separate areas, low-energy nuclear reactions, intermediate energy physics, and nuclear structure studies. Although the subjects are thus spread among different areas, they are based on two techniques developed in previous years. These techniques are a powerful method for continuum-random-phase-approximation (CRPA) calculations of nuclear response and the breakup-fusion (BF) approach to incomplete fusion reactions, which calculation on a single footing of various incomplete fusion reaction cross sections within the framework of direct reaction theories. The approach was developed as a part of a more general program for establishing an approach to describing all different types of nuclear reactions, i.e., complete fusion, incomplete fusion and direct reactions, in a systematic way based on single theoretical framework

Reference Cross Sections for Charged-particle Monitor Reactions

Czech Academy of Sciences Publication Activity Database

Hermanne, A.; Ignatyuk, A. V.; Capote, R.; Carlson, B. V.; Engle, J. W.; Kellett, M. A.; Kibédi, T.; Kim, G.; Kondev, F. G.; Hussain, M.; Lebeda, Ondřej; Luca, A.; Nagai, Y.; Naik, H.; Nichols, A. L.; Nortier, F. M.; Suryanarayana, S. V.; Takacs, S.; Tarkanyi, F. T.; Verpelli, M.

2018-01-01

Roč. 148, SI (2018), s. 338-382 ISSN 0090-3752 Institutional support: RVO:61389005 Keywords : deuteron induced reactions * proton induced reactions * cross sections Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders OBOR OECD: Nuclear physics Impact factor: 1.146, year: 2016

Physical Allergy

Science.gov (United States)

... Autologous Stem Cell Transplant Additional Content Medical News Physical Allergy By Peter J. Delves, PhD, Professor of ... Disorders Exercise-Induced Allergic Reactions Food Allergy Mastocytosis Physical Allergy Seasonal Allergies Year-Round Allergies A physical ...

Rate constant computation on some elementary reactions of Hg during combustion

Energy Technology Data Exchange (ETDEWEB)

Wang, Qing; Yang, Bo-wen; Bai, Jing-ru [Northeast Dianli Univ., Jilin (China). Inst. of Energy and Power Engineering

2013-07-01

The geometry optimizations of reactants, products and transition states were made by the quantum chemistry MP2 method at the SDD basis function level for Hg, and 6-311++G(3df, 3pd) for others. The properties of stable minimums were validated by vibration frequencies analysis. Furthermore, the microcosmic chemical reaction mechanisms of reactions were investigated by ab initio calculations of quantum chemistry. On the basis of the geometry optimization, reaction rate constants within 298-2,000 K are calculated neither from experimental data nor by estimated, but directly from Quantum Chemistry software-Khimera.

Introduction to nuclear reactions

International Nuclear Information System (INIS)

Satchler, G.R.

1980-01-01

This introduction to nuclear reaction phenomena is aimed primarily but not exclusively at readers at the undergraduate student level. An overview of the subject is presented in the first two chapters entitled - Some background information and Introduction to nuclear reactions. The third chapter reviews scattering theory with emphasis on the underlying physical ideas and also provides schematic entrees to the more advanced topics. The physical models which have been developed to account for the various aspects of nuclear phenomena are described in more detail in chapter 4. References and exercises are appended to each chapter. (U.K.)

Child Physical Abuse and the Related PTSD in Taiwan: The Role of Chinese Cultural Background and Victims' Subjective Reactions

Science.gov (United States)

Chou, Chia-Ying; Su, Yi-Jen; Wu, Ho-Mao; Chen, Sue-Huei

2011-01-01

Objective: This study aimed to investigate child physical abuse (CPA) while taking into account the more rigorous definitions of CPA in the Chinese societies. The prevalence of CPA and CPA-related PTSD were estimated, together with the examination of peri-traumatic subjective reactions and their impacts on PTSD. Methods: In a Taiwanese sample of…

Department of Nuclear Reactions: Overview

International Nuclear Information System (INIS)

Rusek, K.

2000-01-01

Full text: During last year the physicists of the Department of Nuclear Reactions were involved in many experiments and projects: -Low energy nuclear reactions: For the first time a heavy ion beam from the Warsaw Cyclotron C-200 was used to investigate elastic and inelastic scattering of 12 C ions from 12 C target. The experiment is a part of a long range programme devoted to study the energy dependence of the nucleus-nucleus interactions. -Multifragmentation of relativistic heavy ions: Multifragmentation reactions induced by 12 C on different heavy targets and at different energies were studied in experiments performed at Gesellschaft fuer Schwerionenforschung by the ALADIN Collaboration. These asymmetric systems were investigated in order to study the interplay between preequilibrium and equilibrium phenomena in the nuclear liquid - gas phase transition. -The structure of nucleons: A novel, two-structure description of the Roper resonance was proposed on the basis of the α-p scattering data reanalysed by means of a T-matrix formalism. -Atomic physics: Emission of the X-rays by fast heavy ions (S, Ti, Fe) as they traverse the matter (thin carbon or other light element foil) was investigated in a series of experiments performed at University of Erlangen. It was demonstrated, that the characteristic K α X-rays emitted by a heavy ion can serve as a tool for Z-value control of the ion. -Material research: Semiconductor heterostructures were investigated by means of Rutherford Back Scattering and Channeling methods using the 2 MeV α particles from the Van de Graaff accelerator ''Lech'' at the Department. The following reports present the results and major successes which were achieved in 1999. (author)

Kinematic relations in heavy-ion reactions

International Nuclear Information System (INIS)

Gippner, P.; Kalpakchieva, R.

1988-01-01

The present work gives a short overview of the non-relativistic kinematics of nuclear reactions derived on the basis of the conservation laws of energy and linear momentum. Section 2 contains kinematic relations valid for two-body reactions, sections 3 makes use of these relations to describe sequential fission as a special case of reactions with three particles in the exit channel. It is the aim of this work to comprise the kinematic formulae essential for planning of experiments, data analysis and critical examination of the obtained results. (author)

Physical basis for biological effect

International Nuclear Information System (INIS)

Goodhead, D.T.

1987-01-01

Absorbed dose, or particle fluence, alone, are poor predictors of the biological effectiveness of ionizing radiations. Various radiation 'quality' parameters have been proposed to account quantitatively for the differences due to type of radiation. These include LET, quality factor (Q), lineal energy, specific energy and Z 2 /β 2 . However, all of these have major shortcomings, largely because they fail to describe adequately the microscopic stochastic properties of radiation which are primarily responsible for their relative effectiveness. Most biophysical models of radiation action now agree that the biological effectiveness of radiations are to a large extent determined by their very localized spatial properties of energy deposition (perhaps DNA and associated structures) and that the probability of residual permanent cellular damage (after cellular repair) depends on the nature of this initial macromolecular damage. Common features of these models make it clear that major future advances in identifying critical physical parameters of radiations for general practical application, or to describe their fundamental mechanisms of action, require accurate knowledge of the spatial patterns of energy deposition down to distances of the order of nanometres. Therefore, adequate descriptions are required of the nature and spatial distribution of the initial charged particles and of the interaction-by-interaction structure of the ensuing charged particle tracks. Recent development and application of Monte Carlo track structure simulations have already made it possible to commence such analyses of radiobiological data. (author). 56 refs, 7 figs

High School Forum: "Invitations to Enquiry": The Calcite/Acid Reaction.

Science.gov (United States)

Herron, J. Dudley, Ed.; Driscoll, D. R.

1979-01-01

Describes a high school chemistry experiment which involves the reaction between calcite and hydrochloric and sulfuric acids. This reaction can be carried out as a projected demonstration and on an individual basis. (HM)

Evolution in time of an N-atom system. I. A physical basis set for the projection of the master equation

International Nuclear Information System (INIS)

Freedhoff, Helen

2004-01-01

We study an aggregate of N identical two-level atoms (TLA's) coupled by the retarded interatomic interaction, using the Lehmberg-Agarwal master equation. First, we calculate the entangled eigenstates of the system; then, we use these eigenstates as a basis set for the projection of the master equation. We demonstrate that in this basis the equations of motion for the level populations, as well as the expressions for the emission and absorption spectra, assume a simple mathematical structure and allow for a transparent physical interpretation. To illustrate the use of the general theory in emission processes, we study an isosceles triangle of atoms, and present in the long wavelength limit the (cascade) emission spectrum for a hexagon of atoms fully excited at t=0. To illustrate its use for absorption processes, we tabulate (in the same limit) the biexciton absorption frequencies, linewidths, and relative intensities for polygons consisting of N=2,...,9 TLA's

Nuclear Physics Research Activity In Vietnam During Period From 2005 To 2007

International Nuclear Information System (INIS)

Tran Duc Thiep

2008-01-01

During the recent years though the difficult conditions as the limit in research budget, the lack in experimental facilities and in manpower, the Nuclear Physics Research in Vietnam still continues to develop and has achieved promising results. This expresses the efforts from the Government as well as from the nuclear physics scientists. In this report we would like to present the Nuclear Physics Research Activity and the achieved results in Vietnam during period from 2005 to 2007 in following directions: Nuclear Reaction and Structure, Nuclear Matter and Nuclear Data, Nuclear Reactor Physics, Nuclear Physics Research based on Accelerators, Physics of Cosmic Rays, Nuclear Physics Related Researches. The report also concerns the problems of manpower, the joining of research institutes in the Country and the expansion of international collaborations in the coming period of the Nuclear Physics Research Activity. The Report was prepared mainly on the basis of the reports that will be presented at the 7th National Conference on Nuclear Science and Technology, held from 30-31 August 2007 in Danang city. (author)

An analytical solution of Richards' equation providing the physical basis of SCS curve number method and its proportionality relationship

Science.gov (United States)

Hooshyar, Milad; Wang, Dingbao

2016-08-01

The empirical proportionality relationship, which indicates that the ratio of cumulative surface runoff and infiltration to their corresponding potentials are equal, is the basis of the extensively used Soil Conservation Service Curve Number (SCS-CN) method. The objective of this paper is to provide the physical basis of the SCS-CN method and its proportionality hypothesis from the infiltration excess runoff generation perspective. To achieve this purpose, an analytical solution of Richards' equation is derived for ponded infiltration in shallow water table environment under the following boundary conditions: (1) the soil is saturated at the land surface; and (2) there is a no-flux boundary which moves downward. The solution is established based on the assumptions of negligible gravitational effect, constant soil water diffusivity, and hydrostatic soil moisture profile between the no-flux boundary and water table. Based on the derived analytical solution, the proportionality hypothesis is a reasonable approximation for rainfall partitioning at the early stage of ponded infiltration in areas with a shallow water table for coarse textured soils.

A dynamical theory of incomplete fusion reactions: The breakup-fusion reaction approach

International Nuclear Information System (INIS)

Udagawa, T.

1984-01-01

A dynamical theory of partial fusion reactions is presented, which may fill the gap between direct and compound nuclear reaction theories. With the new theory one can calculate partial fusion taking place in three-body (and many more) channels reached via direct reactions, e.g., breakup and knockout reactions. The authors present first the results for the cross section for such reactions, taking as an example breakup followed by fusion. They then discuss a physical picture which emerges from their theory, namely that the partial fusion reactions, particularly of the massive-transfer type, take place in a so-called deep peripheral region. It is also shown that the deep peripheral character of such processes diminishes as the mass of the fused system decreases, so that the reactions essentially evolve to the usual peripheral character. Finally, comparisons are made of results of numerical calculations with experimental data, taking as an example the /sup 159/Tb(/sup 14/N,α) reaction with E/sub lab/ = 95 MeV

Thermodynamics of Enzyme-Catalyzed Reactions Database

Science.gov (United States)

SRD 74 Thermodynamics of Enzyme-Catalyzed Reactions Database (Web, free access)   The Thermodynamics of Enzyme-Catalyzed Reactions Database contains thermodynamic data on enzyme-catalyzed reactions that have been recently published in the Journal of Physical and Chemical Reference Data (JPCRD). For each reaction the following information is provided: the reference for the data, the reaction studied, the name of the enzyme used and its Enzyme Commission number, the method of measurement, the data and an evaluation thereof.

Nuclear physics

International Nuclear Information System (INIS)

Patel, S.B.

1991-01-01

This book is a simple and direct introduction to the tools of modern nuclear physics, both experimental and mathematical. Emphasizes physical intuition and illuminating analogies, rather than formal mathematics. Topics covered include particle accelerators, radioactive series, types of nuclear reactions, detection of the neutrino, nuclear isomerism, binding energy of nuclei, fission chain reactions, and predictions of the shell model. Each chapter contains problems and illustrative examples. Pre-requisites are calculus and elementary vector analysis

Fluid flow and reaction fronts: characterization of physical processes at the microscale using SEM analyses

Science.gov (United States)

Beaudoin, Nicolas; Koehn, Daniel; Toussaint, Renaud; Gomez-Rivas, Enrique; Bons, Paul; Chung, Peter; Martín-Martín, Juan Diego

2014-05-01

Fluid migrations are the principal agent for mineral replacement in the upper crust, leading to dramatic changes in the porosity and permeability of rocks over several kilometers. Consequently, a better understanding of the physical parameters leading to mineral replacement is required to better understand and model fluid flow and rock reservoir properties. Large-scale dolostone bodies are one of the best and most debated examples of such fluid-related mineral replacement. These formations received a lot of attention lately, and although genetic mechanics and implications for fluid volume are understood, the mechanisms controlling the formation and propagation of the dolomitization reaction front remain unclear. This contribution aims at an improvement of the knowledge about how this replacement front propagates over space and time. We study the front sharpness on hand specimen and thin section scale and what the influence of advection versus diffusion of material is on the front development. In addition, we demonstrate how preexisting heterogeneities in the host rock affect the propagation of the reaction front. The rock is normally not homogeneous but contains grain boundaries, fractures and stylolites, and such structures are important on the scale of the front width. Using Scanning Electron Microscopy and Raman Spectroscopy we characterized the reaction front chemistry and morphology in different context. Specimens of dolomitization fronts, collected from carbonate sequences of the southern Maestrat Basin, Spain and the Southwestern Scottish Highlands suggest that the front thickness is about several mm being relatively sharp. Fluid infiltrated grain boundaries and fractures forming mm-scale transition zone. We study the structure of the reaction zone in detail and discuss implications for fluid diffusion-advection models and mineral replacement. In addition we formulate a numerical model taking into account fluid flow, diffusion and advection of the mobile

Nuclear Reaction Data Centers

International Nuclear Information System (INIS)

McLane, V.; Nordborg, C.; Lemmel, H.D.; Manokhin, V.N.

1988-01-01

The cooperating Nuclear Reaction Data Centers are involved in the compilation and exchange of nuclear reaction data for incident neutrons, charged particles and photons. Individual centers may also have services in other areas, e.g., evaluated data, nuclear structure and decay data, reactor physics, nuclear safety; some of this information may also be exchanged between interested centers. 20 refs., 1 tab

Laser spot detection based on reaction diffusion

Czech Academy of Sciences Publication Activity Database

Vázquez-Otero, Alejandro; Khikhlukha, Danila; Solano-Altamirano, J. M.; Dormido, R.; Duro, N.

2016-01-01

Roč. 16, č. 3 (2016), s. 1-11, č. článku 315. ISSN 1424-8220 R&D Projects: GA MŠk EF15_008/0000162 Grant - others:ELI Beamlines(XE) CZ.02.1.01/0.0/0.0/15_008/0000162 Institutional support: RVO:68378271 Keywords : laser spot detection * laser beam detection * reaction diffusion models * Fitzhugh-Nagumo model * reaction diffusion computation * Turing patterns Subject RIV: BL - Plasma and Gas Discharge Physics OBOR OECD: Fluids and plasma physics (including surface physics) Impact factor: 2.677, year: 2016

Developing the Physics Basis of Fast Ignition Experiments at Future Large Fusion-class lasers

International Nuclear Information System (INIS)

Mackinnon, A J; Key, M H; Hatchett, S; MacPhee, A G; Foord, M; Tabak, M; Town, R J; Patel, P K

2008-01-01

The Fast Ignition (FI) concept for Inertial Confinement Fusion (ICF) has the potential to provide a significant advance in the technical attractiveness of Inertial Fusion Energy (IFE) reactors. FI differs from conventional 'central hot spot' (CHS) target ignition by using one driver (laser, heavy ion beam or Z-pinch) to create a dense fuel and a separate ultra-short, ultra-intense laser beam to ignite the dense core. FI targets can burn with ∼ 3X lower density fuel than CHS targets, resulting in (all other things being equal) lower required compression energy, relaxed drive symmetry, relaxed target smoothness tolerances, and, importantly, higher gain. The short, intense ignition pulse that drives this process interacts with extremely high energy density plasmas; the physics that controls this interaction is only now becoming accessible in the lab, and is still not well understood. The attraction of obtaining higher gains in smaller facilities has led to a worldwide explosion of effort in the studies of FI. In particular, two new US facilities to be completed in 2009/2010, OMEGA/OMEGA EP and NIF-ARC (as well as others overseas) will include FI investigations as part of their program. These new facilities will be able to approach FI conditions much more closely than heretofore using direct drive (dd) for OMEGA/OMEGA EP and indirect drive (id) for NIF-ARC. This LDRD has provided the physics basis for the development of the detailed design for integrated Fast ignition experiments on these facilities on the 2010/2011 timescale. A strategic initiative LDRD has now been formed to carry out integrated experiments using NIF ARC beams to heat a full scale FI assembled core by the end of 2010

Integration of Computational and Preparative Techniques to Demonstrate Physical Organic Concepts in Synthetic Organic Chemistry: An Example Using Diels-Alder Reaction

Science.gov (United States)

Palmer, David R. J.

2004-01-01

The Diels-Alder reaction is used as an example for showing the integration of computational and preparative techniques, which help in demonstrating the physical organic concepts in synthetic organic chemistry. These experiments show that the students should not accept the computational results without questioning them and in many Diels-Alder…

International Thermonuclear Experimental Reactor: Physics issues, capabilities and physics program plans

International Nuclear Information System (INIS)

Wesley, J.C.

1997-01-01

Present status and understanding of the principal plasma-performance determining physics issues that affect the physics design and operational capabilities of the International Thermonuclear Experimental Reactor (ITER) [ITER EDA Agreement and Protocol 2 (International Atomic Energy Agency, Vienna, 1994)] are presented. Emphasis is placed on the five major physics-basis issues emdash energy confinement, beta limit, density limit, impurity dilution and radiation loss, and the feasibility of obtaining partial-detached divertor operation emdash that directly affect projections of ITER fusion power and burn duration performance. A summary of these projections is presented and the effect of uncertainties in the physics-basis issues is examined. ITER capabilities for experimental flexibility and plasma-performance optimization are also described, and how these capabilities may enter into the ITER physics program plan is discussed. copyright 1997 American Institute of Physics

Intermediate energy nuclear physics (Task C) and charge exchange reactions (Task W). Technical progress report, October 1, 1985-October 1, 1986

International Nuclear Information System (INIS)

Kraushaar, J.J.

1986-10-01

This report describes the experimental work in intermediate energy research carried out over the past year at the University of Colorado. The experimental program is very broad in nature, ranging from investigations in pion-nucleus interactions, nucleon charge exchange, inelastic electron scattering, and nucleon transfer reactions. The experiments were largely carried out at the Los Alamos Meson Physics Facility, but important programs were conducted at the Tri-University Meson Facility at the University of British Columbia, the Indiana University Cyclotron Facility and Netherlands Institute for Nuclear Physics Research (NIKHEF-K)

Kinetics of Single-Enzyme Reactions on Vesicles: Role of Substrate Aggregation

Science.gov (United States)

Zhdanov, Vladimir P.

2015-03-01

Enzymatic reactions occurring in vivo on lipid membranes can be influenced by various factors including macromolecular crowding in general and substrate aggregation in particular. In academic studies, the role of these factors can experimentally be clarified by tracking single-enzyme kinetics occurring on individual lipid vesicles. To extend the conceptual basis for such experiments, we analyze herein the corresponding kinetics mathematically with emphasis on the role of substrate aggregation. In general, the aggregation may occur on different length scales. Small aggregates may e.g. contain a few proteins or peptides while large aggregates may be mesoscopic as in the case of lipid domains which can be formed in the membranes composed of different lipids. We present a kinetic model describing comprehensively the effect of aggregation of the former type on the dependence of the reaction rate on substrate membrane concentration. The results obtained with physically reasonable parameters indicate that the aggregation-related deviations from the conventional Michaelis-Menten kinetics may be appreciable. Special Issue Comments: This theoretical article is focused on single-enzyme reactions occurring in parallel with substrate aggregation on individual vesicles. This subject is related to a few Special Issue articles concerning enzyme dynamics6,7 and function8 and mathematical aspects of stochastic kinetics.9

The quantum dynamics of electronically nonadiabatic chemical reactions

Science.gov (United States)

Truhlar, Donald G.

1993-01-01

Considerable progress was achieved on the quantum mechanical treatment of electronically nonadiabatic collisions involving energy transfer and chemical reaction in the collision of an electronically excited atom with a molecule. In the first step, a new diabatic representation for the coupled potential energy surfaces was created. A two-state diabatic representation was developed which was designed to realistically reproduce the two lowest adiabatic states of the valence bond model and also to have the following three desirable features: (1) it is more economical to evaluate; (2) it is more portable; and (3) all spline fits are replaced by analytic functions. The new representation consists of a set of two coupled diabatic potential energy surfaces plus a coupling surface. It is suitable for dynamics calculations on both the electronic quenching and reaction processes in collisions of Na(3p2p) with H2. The new two-state representation was obtained by a three-step process from a modified eight-state diatomics-in-molecules (DIM) representation of Blais. The second step required the development of new dynamical methods. A formalism was developed for treating reactions with very general basis functions including electronically excited states. Our formalism is based on the generalized Newton, scattered wave, and outgoing wave variational principles that were used previously for reactive collisions on a single potential energy surface, and it incorporates three new features: (1) the basis functions include electronic degrees of freedom, as required to treat reactions involving electronic excitation and two or more coupled potential energy surfaces; (2) the primitive electronic basis is assumed to be diabatic, and it is not assumed that it diagonalizes the electronic Hamiltonian even asymptotically; and (3) contracted basis functions for vibrational-rotational-orbital degrees of freedom are included in a very general way, similar to previous prescriptions for locally

Gribov's reggeon calculus: its physical basis and implications

International Nuclear Information System (INIS)

Baker, M.; Ter-Martirosyan, K.A.

1976-01-01

The equations of Gribov's Reggeon calculus and the cutting rules of Abramovskii, Gribov and Kancheli are derived from the assumption that processes involving large virtual masses are damped. The discussion is carried out entirely in the s channel and no use is made of the details of any particular field theory. Both the mathematical development and the physical picture which evolves rest on the assumed multiperipheral origin of Regge behavior. (Auth.)

Reaction theories for N* excitations in πN and γN reactions

International Nuclear Information System (INIS)

Lee, T.S.H.

1996-01-01

The importance of developing reaction theories for investigating N* physics is illustrated in an analysis of pion photoproduction on the nucleon. It is shown that the γN ↔ Δ transition amplitudes predicted by the constituent quark model are in agreement with the values extracted from the γN → πN data only when the contributions from the reaction mechanisms calculated using a dynamical approach are taken into account in the analysis

Modeling the Electrochemical Hydrogen Oxidation and Evolution Reactions on the Basis of Density Functional Theory Calculations

DEFF Research Database (Denmark)

Skulason, Egill; Tripkovic, Vladimir; Björketun, Mårten

2010-01-01

charged Pt(111) slab and solvated protons in up to three water bilayers is considered and reaction energies and activation barriers are determined by using a newly developed computational scheme where the potential can be kept constant during a charge transfer reaction. We determine the rate limiting...... reaction on Pt(111) to be Tafel−Volmer for HOR and Volmer−Tafel for HER. Calculated rates agree well with experimental data. Both the H adsorption energy and the energy barrier for the Tafel reaction are then calculated for a range of metal electrodes, including Au, Ag, Cu, Pt, Pd, Ni, Ir, Rh, Co, Ru, Re......, W, Mo, and Nb, different facets, and step of surfaces. We compare the results for different facets of the Pt electrode to experimental data. Our results suggest that the most important parameter for describing the HOR or the HER activity of an electrode is its binding free energy of H. We present...

Nuclear reaction studies: Progress report

International Nuclear Information System (INIS)

Thaler, R.M.

1986-01-01

A principal focus of recent research has been the three-body problem. A great deal of effort has been devoted to the creation of a computer program to calculate physical observables in the three body problem below 1 GeV. Successful results have been obtained for the triton. Additional work concerns scattering of K + mesons from nuclei, antinucleon physics, relativistic nuclear physics and inclusive reactions

Theoretical femtosecond physics atoms and molecules in strong laser fields

CERN Document Server

Grossmann, Frank

2013-01-01

Theoretical investigations of atoms and molecules interacting with pulsed or continuous wave lasers up to atomic field strengths on the order of 10^16 W/cm² are leading to an understanding of many challenging experimental discoveries. This book deals with the basics of femtosecond physics and goes up to the latest applications of new phenomena. The book presents an introduction to laser physics with mode-locking and pulsed laser operation. The solution of the time-dependent Schrödinger equation is discussed both analytically and numerically. The basis for the non-perturbative treatment of laser-matter interaction in the book is the numerical solution of the time-dependent Schrödinger equation. The light field is treated classically, and different possible gauges are discussed. Physical phenonema, ranging from Rabi-oscillations in two-level systems to the ionization of atoms, the generation of high harmonics, the ionization and dissociation of molecules as well as the control of chemical reactions are pre...

The pairing theory - its physical basis and its consequences

International Nuclear Information System (INIS)

Schrieffer, J.R.

1992-01-01

The key developments which set the scene for the microscopic theory of superconductivity are discussed and the physical reasoning which lead to the pairing theory is presented. Consequences of the BCS theory are reviewed. (orig.)

Theoretical physics division

International Nuclear Information System (INIS)

Anon.

The studies in 1977 are reviewed. In theoretical nuclear physics: nuclear structure, nuclear reactions, intermediate energy physics; in elementary particle physics: field theory, strong interactions dynamics, nucleon-nucleon interactions, new particles, current algebra, symmetries and quarks are studied [fr

Proceedings of the meeting on tunneling reaction and low temperature chemistry, 97 October. Tunneling reaction and quantum medium

Energy Technology Data Exchange (ETDEWEB)

Miyazaki, Tetsuo; Aratono, Yasuyuki; Ichikawa, Tsuneki; Shiotani, Masaru [eds.

1998-02-01

Present report is the proceedings of the 3rd Meeting on Tunneling Reaction and Low Temperature Chemistry held in Oct. 13 and 14, 1997. The main subject of the meeting is `Tunneling Reaction and Quantum Medium`. In the meeting, the physical and chemical phenomena in the liquid helium such as quantum nucleation, spectroscopy of atoms and molecules, and tunneling abstraction reaction of tritium atom were discussed as the main topics as well as the tunneling reactions in the solid hydrogen and organic compounds. Through the meetings held in 1995, 1996, and 1997, the tunneling phenomena proceeding at various temperatures (room temperature to mK) in the wide fields of chemistry, biology, and physics were discussed intensively and the importance of the tunneling phenomena in the science has been getting clear. The 12 of the presented papers are indexed individually. (J.P.N.)

Proceedings of the meeting on tunneling reaction and low temperature chemistry, 97 October. Tunneling reaction and quantum medium

International Nuclear Information System (INIS)

Miyazaki, Tetsuo; Aratono, Yasuyuki; Ichikawa, Tsuneki; Shiotani, Masaru

1998-02-01

Present report is the proceedings of the 3rd Meeting on Tunneling Reaction and Low Temperature Chemistry held in Oct. 13 and 14, 1997. The main subject of the meeting is 'Tunneling Reaction and Quantum Medium'. In the meeting, the physical and chemical phenomena in the liquid helium such as quantum nucleation, spectroscopy of atoms and molecules, and tunneling abstraction reaction of tritium atom were discussed as the main topics as well as the tunneling reactions in the solid hydrogen and organic compounds. Through the meetings held in 1995, 1996, and 1997, the tunneling phenomena proceeding at various temperatures (room temperature to mK) in the wide fields of chemistry, biology, and physics were discussed intensively and the importance of the tunneling phenomena in the science has been getting clear. The 12 of the presented papers are indexed individually. (J.P.N.)

Nuclear Physics Laboratory 1976 annual report. [Nuclear Physics Laboratory, Univ. of Washington

Energy Technology Data Exchange (ETDEWEB)

1976-06-01

Laboratory activities for the period spring, 1975 to spring, 1976 are described. The emphasis of the work can be discerned from the chapter headings: accelerator development; ion source development; instrumentation, detectors, research techniques; computer and computing; atomic physics; nuclear astrophysics; fundamental symmetries in nuclei; nuclear structure; radiative capture measurements and calculations; scattering and reactions; reactions with polarized protons and deuterons; heavy-ion elastic and inelastic scattering; heavy-ion deeply inelastic and fusion reactions; heavy ion transfer and intermediate structure reactions; medium-energy physics; and energy studies. Research by users and visitors is also described; and laboratory personnel, degrees granted, and publications are listed. Those summaries having significant amounts of information are indexed individually. (RWR)

Final-state interactions and relativistic effects in the quasielastic (e,e') reaction

International Nuclear Information System (INIS)

Chinn, C.R.; Physics Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545); Picklesimer, A.; Van Orden, J.W.

1989-01-01

The longitudinal and transverse response functions for the inclusive quasielastic (e,e') reaction are analyzed in detail. A microscopic theoretical framework for the many-body reaction provides a clear conceptual (nonrelativistic) basis for treating final-state interactions and goes far beyond simple plane-wave or Hermitean potential models. The many-body physics of inelastic final-state channels as described by optical and multiple scattering theories is properly included by incorporating a full complex optical potential. Explicit nonrelativistic and relativistic momentum-space calculations quantitatively demonstrate the importance of such a treatment of final-state interactions for both the transverse and longitudinal response. Nonrelativistic calculations are performed using final-state interactions based on phenomenology, local density models, and microscopic multiple scattering theory. Relativistic calculations span a similar range of models and employ Dirac bound-state wave functions. The theoretical extension to relativistic dynamics is of course not clear, but is done in obvious parallel to elastic proton scattering. Extensive calculations are performed for 40 Ca at momentum transfers of 410, 550, and 700 MeV/c. A number of interesting physical effects are observed, including significant relativistic suppressions (especially for R L ), large off-shell and virtual pair effects, enhancement of the tails of the response by the final-state interactions, and large qualitative and even shape distinctions between the predictions of the various models of the final-state interactions. None of the models is found to be able to simultaneously predict the data for both response functions. This strongly suggests that additional physical mechanisms are of qualitative importance in inclusive quasielastic electron scattering

The Importance of Physical Literacy for Physical Education and Recreation

Science.gov (United States)

Basoglu, Umut Davut

2018-01-01

As the basis of characteristics, qualifications, behaviors, awareness, knowledge and understanding of the development of healthy active living and physical recreation opportunities Physical Literacy (PL); has become a global concern in the fields of physical education and recreation since its first use as a term. Experts from different countries…

Characterization of excited-state reactions with instant spectra of fluorescence kinetics

International Nuclear Information System (INIS)

Tomin, Vladimir I.; Ushakou, Dzmitryi V.

2015-01-01

Comprehensible knowledge of the excited-state proton transfer processes in organic compounds is overwhelmingly important not only for physics, but also chemistry and Life Sciences, since they play a key role in main processes of photosynthesis and functioning of biological organisms. Moreover compounds with Excited-State Intramolecular Proton Transfer (ESIPT) are in the focus of the interest of scientists throughout the world, because dual fluorescence spectra of such objects corresponding to two forms of molecular structure (normal and photoproduct) are very sensitive to characteristics of molecular microenvironment. This property allows to use such substances as fluorescent probes for diverse applications in chemistry and Life Sciences. But at the same time studying of proton transfer processes is not simple, because this process is characterized by extremely fast times (on picoseconds time scale and less order) and very often contribution of reverse reactions is essentially complicates an interpretation of observed properties of dual fluorescence. Hence, understanding of a role of reversible reactions is crucial for a comprehensive description of all processes accompanying excited state reactions. We discuss new approach for treatment ESIPT reaction on the basis of experimentally measured instant spectra of dual fluorescence and temporal behavior of ratiometric signal of normal to tautomer form intensities. Simple analytical expressions show in transparent way how to distinguish a degree of reverse reaction contribution to ratiometric signal. A validation of the approach under consideration is fulfilled with two different flavonols – 3-hydroxyflavone and 4′-(Dimethylamino)-3-hydroxyflavone – representing two extreme cases in affecting reversible reaction on dual emission. A comparing of new approach and traditional method when we analyze kinetics of separate the N* and T* fluorescence bands decays, has been carried out. - Highlights: • The excited

Characterization of excited-state reactions with instant spectra of fluorescence kinetics

Energy Technology Data Exchange (ETDEWEB)

Tomin, Vladimir I., E-mail: tomin@apsl.edu.pl; Ushakou, Dzmitryi V.

2015-10-15

Comprehensible knowledge of the excited-state proton transfer processes in organic compounds is overwhelmingly important not only for physics, but also chemistry and Life Sciences, since they play a key role in main processes of photosynthesis and functioning of biological organisms. Moreover compounds with Excited-State Intramolecular Proton Transfer (ESIPT) are in the focus of the interest of scientists throughout the world, because dual fluorescence spectra of such objects corresponding to two forms of molecular structure (normal and photoproduct) are very sensitive to characteristics of molecular microenvironment. This property allows to use such substances as fluorescent probes for diverse applications in chemistry and Life Sciences. But at the same time studying of proton transfer processes is not simple, because this process is characterized by extremely fast times (on picoseconds time scale and less order) and very often contribution of reverse reactions is essentially complicates an interpretation of observed properties of dual fluorescence. Hence, understanding of a role of reversible reactions is crucial for a comprehensive description of all processes accompanying excited state reactions. We discuss new approach for treatment ESIPT reaction on the basis of experimentally measured instant spectra of dual fluorescence and temporal behavior of ratiometric signal of normal to tautomer form intensities. Simple analytical expressions show in transparent way how to distinguish a degree of reverse reaction contribution to ratiometric signal. A validation of the approach under consideration is fulfilled with two different flavonols – 3-hydroxyflavone and 4′-(Dimethylamino)-3-hydroxyflavone – representing two extreme cases in affecting reversible reaction on dual emission. A comparing of new approach and traditional method when we analyze kinetics of separate the N* and T* fluorescence bands decays, has been carried out. - Highlights: • The excited

Stress-associated cardiovascular reaction masks heart rate dependence on physical load in mice.

Science.gov (United States)

Andreev-Andrievskiy, A A; Popova, A S; Borovik, A S; Dolgov, O N; Tsvirkun, D V; Custaud, M; Vinogradova, O L

2014-06-10

When tested on the treadmill mice do not display a graded increase of heart rate (HR), but rather a sharp shift of cardiovascular indices to high levels at the onset of locomotion. We hypothesized that under test conditions cardiovascular reaction to physical load in mice is masked with stress-associated HR increase. To test this hypothesis we monitored mean arterial pressure (MAP) and heart rate in C57BL/6 mice after exposure to stressful stimuli, during spontaneous locomotion in the open-field test, treadmill running or running in a wheel installed in the home cage. Mice were treated with β1-adrenoblocker atenolol (2mg/kg ip, A), cholinolytic ipratropium bromide (2mg/kg ip, I), combination of blockers (A+I), anxiolytic diazepam (5mg/kg ip, D) or saline (control trials, SAL). MAP and HR in mice increased sharply after handling, despite 3weeks of habituation to the procedure. Under stressful conditions of open field test cardiovascular parameters in mice were elevated and did not depend on movement speed. HR values did not differ in I and SAL groups and were reduced with A or A+I. HR was lower at rest in D pretreated mice. In the treadmill test HR increase over speeds of 6, 12 and 18m/min was roughly 1/7-1/10 of HR increase observed after placing the mice on the treadmill. HR could not be increased with cholinolytic (I), but was reduced after sympatholytic (A) or A+I treatment. Anxiolytic (D) reduced heart rate at lower speeds of movement and its overall effect was to unmask the dependency of HR on running speed. During voluntary running in non-stressful conditions of the home cage HR in mice linearly increased with increasing running speeds. We conclude that in test situations cardiovascular reactions in mice are governed predominantly by stress-associated sympathetic activation, rendering efforts to evaluate HR and MAP reactions to workload unreliable. Copyright © 2014 Elsevier Inc. All rights reserved.

Atomic nuclei and nuclear reactions. Theory and application

International Nuclear Information System (INIS)

Sitenko, A.G.; Tartakovsky, V.K.; Kenjebaev, K.K.; Shunkeyev, K.Sh.; Ismatov, E.I.; Mukhammedov, S.; Comsan, M.N.H.; Djuraev, Sh.Kh.

2004-01-01

Full text: The short description of the book preparation by the collective authors from Ukraine, Kazakhstan, Uzbekistan and Egypt is given. The present book is the expanded course of lectures on the theory of nuclei, nuclear reactions and their applications delivered by the authors for a number of years in the Ukrainian National University, Aktubinsk State University of the Kazakhstan Republic, Tashkent National University, Samarkand and Termez State Universities of Uzbekistan Republic, Egyptian National Universities (Al-Az'har, Menoufeya, Suez-Canal and Tanta) and the Institute of Nuclear Physics of the Academy of Sciences of the Republic of Uzbekistan. The lectures present foundations of the modern concepts of the structure of nuclei, on the nature of nuclear processes and nuclear transformations. Main attention in the book was paid to the presentation of the basics and some modern achievements in the field of the theory of nuclei and nuclear reactions. A number of problems was investigated in original works and were not presented in the physics textbooks. The book presents the non-relativistic theory of nuclear reactions, questions of relativistic nuclear physics were not considered here. Non-relativistic theory of nuclear reactions is based on the notions of collision matrix or S-matrix. In absence of consequent microscopic theory, the scattering matrix can be found phenomenological based on definite assumptions on the character of nuclear interactions. Modern applications of nuclear reactions for the development of nuclear methods of analysis are presented. The delayed and nuclear techniques with nuclear reactor, accelerators and radioisotopic sources are considered. The book is designed as a textbook for bachelor and postgraduate students of physical faculties of universities and engineering-physical institutions, lecturers and researchers, working in the field of nuclear physics. The book gives an up-to-date list of references on nuclear reaction theory and

Physics Basis for a Spherical Torus Power Plant

International Nuclear Information System (INIS)

Kessel, C.E.; Menard, J.; Jardin, S.C.; Mau, T.K.

1999-01-01

The spherical torus, or low-aspect-ratio tokamak, is considered as the basis for a fusion power plant. A special class of wall-stabilized high-beta high-bootstrap fraction low-aspect-ratio tokamak equilibrium are analyzed with respect to MHD stability, bootstrap current and external current drive, poloidal field system requirements, power and particle exhaust and plasma operating regime. Overall systems optimization leads to a choice of aspect ratio A = 1:6, plasma elongation kappa = 3:4, and triangularity delta = 0:64. The design value for the plasma toroidal beta is 50%, corresponding to beta N = 7:4, which is 10% below the ideal stability limit. The bootstrap fraction of 99% greatly alleviates the current drive requirements, which are met by tangential neutral beam injection. The design is such that 45% of the thermal power is radiated in the plasma by Bremsstrahlung and trace Krypton, with Neon in the scrapeoff layer radiating the remainder

On intermediate structures in heavy ion reactions

International Nuclear Information System (INIS)

Rotter, I.

1977-01-01

The conceptions of the nuclear reaction theory are reinvestigated on the basis of the continuum shell model. The correlation of the resonance states via the continuum can lead to intermediate structures in the cross section. (Auth.)

BAYESIAN ESTIMATION OF THERMONUCLEAR REACTION RATES

Energy Technology Data Exchange (ETDEWEB)

Iliadis, C.; Anderson, K. S. [Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3255 (United States); Coc, A. [Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), CNRS/IN2P3, Univ. Paris-Sud, Université Paris–Saclay, Bâtiment 104, F-91405 Orsay Campus (France); Timmes, F. X.; Starrfield, S., E-mail: iliadis@unc.edu [School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287-1504 (United States)

2016-11-01

The problem of estimating non-resonant astrophysical S -factors and thermonuclear reaction rates, based on measured nuclear cross sections, is of major interest for nuclear energy generation, neutrino physics, and element synthesis. Many different methods have been applied to this problem in the past, almost all of them based on traditional statistics. Bayesian methods, on the other hand, are now in widespread use in the physical sciences. In astronomy, for example, Bayesian statistics is applied to the observation of extrasolar planets, gravitational waves, and Type Ia supernovae. However, nuclear physics, in particular, has been slow to adopt Bayesian methods. We present astrophysical S -factors and reaction rates based on Bayesian statistics. We develop a framework that incorporates robust parameter estimation, systematic effects, and non-Gaussian uncertainties in a consistent manner. The method is applied to the reactions d(p, γ ){sup 3}He, {sup 3}He({sup 3}He,2p){sup 4}He, and {sup 3}He( α , γ ){sup 7}Be, important for deuterium burning, solar neutrinos, and Big Bang nucleosynthesis.

Resilient Control Systems Practical Metrics Basis for Defining Mission Impact

Energy Technology Data Exchange (ETDEWEB)

Craig G. Rieger

2014-08-01

"Resilience” describes how systems operate at an acceptable level of normalcy despite disturbances or threats. In this paper we first consider the cognitive, cyber-physical interdependencies inherent in critical infrastructure systems and how resilience differs from reliability to mitigate these risks. Terminology and metrics basis are provided to integrate the cognitive, cyber-physical aspects that should be considered when defining solutions for resilience. A practical approach is taken to roll this metrics basis up to system integrity and business case metrics that establish “proper operation” and “impact.” A notional chemical processing plant is the use case for demonstrating how the system integrity metrics can be applied to establish performance, and

Design basis threat analysis and implementation of the physical protection system at Nuclear Facility of BATAN Yogyakarta

International Nuclear Information System (INIS)

Syarip

2005-01-01

An analysis to determine the design basis threat (DBT) and its follow-up through the implementation of physical protection system at the nuclear facility of BATAN Yogyakarta has been done. Methodology used for the analysis is based on the IAEA guidance for the development and maintenance of a DBT. Based on the analysis results, it can be concluded that the threat motivation is influenced by political situation (related to the government policy), criminal, sabotage and theft. The characteristics of threats are: not so well organized, terror, theft of materials information, involving insider (collusion), and intimidation to workers. Potential threat could from guests/students who take a practical job or laboratory exercise. Therefore, it is necessary to be anticipated the possibility and its impact of turmoil/demonstrators such as destruction of: lighting, road, fence, sabotage on the electric and communication lines, surrounding the Yogyakarta nuclear facility

Wave Physics Oscillations - Solitons - Chaos

CERN Document Server

Nettel, Stephen

2009-01-01

This textbook is intended for those second year undergraduates in science and engineering who will later need an understanding of electromagnetic theory and quantum mechanics. The classical physics of oscillations and waves is developed at a more advanced level than has been customary for the second year, providing a basis for the quantum mechanics that follows. In this new edition the Green's function is explained, reinforcing the integration of quantum mechanics with classical physics. The text may also form the basis of an "introduction to theoretical physics" for physics majors. The concluding chapters give special attention to topics in current wave physics: nonlinear waves, solitons, and chaotic behavior.

[Physical urticaria].

Science.gov (United States)

Fleischer, M; Grabbe, J

2004-04-01

The different types of physical urticaria are triggered by mechanical and thermal stimuli, as well as electromagnetic waves. Localized forms restricted to the skin and mucous membranes are most common, but generalized urticaria with variable extracutaneous manifestations can also occur. Physical urticaria is usually sporadic but may rarely have a familial form; it is often associated with chronic urticaria. In most instances, the short time interval between the physical stimulus and reaction points to a causal relationship, but in delayed types the exact diagnosis may be missed without provocation tests. The clinical implication of physical urticaria is demonstrated by investigations showing a greater degree of disability in affected patients as compared to other types of urticaria. There is still an incomplete understanding of the crucial pathophysiological aspects; most likely inflammatory reactions involving leukocytes, endothelial cells and nerves stimulated by various mediators play an important role in this form of urticaria.

Hypernuclear physics with a neutral meson spectrometer

International Nuclear Information System (INIS)

Peng, J.C.

1993-01-01

The (K - , π degrees) reaction, which complements the (K - , π - ) and the (π + , K + ) reactions, offers another means to study hypernuclear physics. The physics motivation for measuring the (K - , π degrees) reaction is discussed. The feasibility for detecting π degrees using the LAMPF Neutral Meson Spectrometer is studied with Monte-Carlo simulations. We conclude that the (K - , π degrees) reaction can be well measured at existing kaon beam lines

Remarkable nanoconfinement effects on chemical equilibrium manifested in nucleotide dimerization and H-D exchange reactions.

Science.gov (United States)

Polak, Micha; Rubinovich, Leonid

2011-10-06

Nanoconfinement entropic effects on chemical equilibrium involving a small number of molecules, which we term NCECE, are revealed by two widely diverse types of reactions. Employing statistical-mechanical principles, we show how the NCECE effect stabilizes nucleotide dimerization observed within self-assembled molecular cages. Furthermore, the effect provides the basis for dimerization even under an aqueous environment inside the nanocage. Likewise, the NCECE effect is pertinent to a longstanding issue in astrochemistry, namely the extra deuteration commonly observed for molecules reacting on interstellar dust grain surfaces. The origin of the NCECE effect is elucidated by means of the probability distributions of the reaction extent and related variations in the reactant-product mixing entropy. Theoretical modelling beyond our previous preliminary work highlights the role of the nanospace size in addition to that of the nanosystem size, namely the limited amount of molecules in the reaction mixture. Furthermore, the NCECE effect can depend also on the reaction mechanism, and on deviations from stoichiometry. The NCECE effect, leading to enhanced, greatly variable equilibrium "constants", constitutes a unique physical-chemical phenomenon, distinguished from the usual thermodynamical properties of macroscopically large systems. Being significant particularly for weakly exothermic reactions, the effects should stabilize products in other closed nanoscale structures, and thus can have notable implications for the growing nanotechnological utilization of chemical syntheses conducted within confined nanoreactors.

Experimental technique for study on three-particle reactions in kinematically total experiments with usage of the two-processor complex on the M-400 computer basis

International Nuclear Information System (INIS)

Berezin, F.N.; Kisurin, V.A.; Nemets, O.F.; Ofengenden, R.G.; Pugach, V.M.; Pavlenko, Yu.N.; Patlan', Yu.V.; Savrasov, S.S.

1981-01-01

Experimental technique for investigation of three-particle nuclear reactions in kinematically total experiments is described. The technique provides the storage of one-dimensional and two- dimensional energy spectra from several detectors. A block diagram of the measuring system, using this technique, is presented. The measuring system consists of analog equipment for rapid-slow coincidences and of a two-processor complex on the base of the M-400 computer with a general bus. Application of a two-processor complex, each computer of which has a possibility of direct access to memory of another computer, permits to separate functions of data collection and data operational presentation and to perform necessary physical calculations. Software of the measuring complex which includes programs written using the ASSEMBLER language for the first computer and functional programs written using the BASIC language for the second computer, is considered. Software of the first computer includes the DISPETCHER dialog control program, driver package for control of external devices, of applied program package and system modules. The technique, described, is tested in experiment on investigation of d+ 10 B→α+α+α three- particle reaction at deutron energy of 13.6 MeV. The two-dimensional energy spectrum reaction obtained with the help of the technique described is presented [ru

Theoretical physics division

International Nuclear Information System (INIS)

Anon.

1980-01-01

Research activities of the theoretical physics division for 1979 are described. Short summaries are given of specific research work in the following fields: nuclear structure, nuclear reactions, intermediate energy physics, elementary particles [fr

Spallation reactions; Reactions de spallation

Energy Technology Data Exchange (ETDEWEB)

Cugon, J.

1996-12-31

Spallation reactions dominate the interactions of hadrons with nuclei in the GeV range (from {approx} 0.1 to {approx} 10 GeV). They correspond to a sometimes important ejection of light particles leaving most of the time a residue of mass commensurate with the target mass. The main features of the experimental data are briefly reviewed. The most successful theoretical model, namely the intranuclear cascade + evaporation model, is presented. Its physical content, results and possible improvements are critically discussed. Alternative approaches are shortly reviewed. (author). 84 refs.

SkyNet: Modular nuclear reaction network library

Science.gov (United States)

Lippuner, Jonas; Roberts, Luke F.

2017-10-01

The general-purpose nuclear reaction network SkyNet evolves the abundances of nuclear species under the influence of nuclear reactions. SkyNet can be used to compute the nucleosynthesis evolution in all astrophysical scenarios where nucleosynthesis occurs. Any list of isotopes can be evolved and SkyNet supports various different types of nuclear reactions. SkyNet is modular, permitting new or existing physics, such as nuclear reactions or equations of state, to be easily added or modified.

Mechanisms of inorganic and organometallic reactions

CERN Document Server

The purpose of this series is to provide a continuing critical review of the literature concerned with mechanistic aspects of inorganic and organo­ metallic reactions in solution, with coverage being complete in each volume. The papers discussed are selected on the basis of relevance to the elucidation of reaction mechanisms and many include results of a nonkinetic nature when useful mechanistic information can be deduced. The period of literature covered by this volume is July 1982 through December 1983, and in some instances papers not available for inclusion in the previous volume are also included. Numerical results are usually reported in the units used by the original authors, except where data from different papers are com­ pared and conversion to common units is necessary. As in previous volumes material included covers the major areas of redox processes, reactions of the nonmetallic elements, reaction of inert and labile metal complexes and the reactions of organometallic compounds. While m...

Estimation and prediction of convection-diffusion-reaction systems from point measurement

NARCIS (Netherlands)

Vries, D.

2008-01-01

Different procedures with respect to estimation and prediction of systems characterized by convection, diffusion and reactions on the basis of point measurement data, have been studied. Two applications of these convection-diffusion-reaction (CDR) systems have been used as a case study of the

Development of the neural net technique for particle physics. Study of the e+e- → Z0 → γH reaction

International Nuclear Information System (INIS)

Guicheney, C.

1992-01-01

This study is concerned with the application of pattern recognition methods through neural networks to High Energy physics. Two methods, Hopfield nets and multilayer nets, are analyzed and shown to have high potential for (resp.) clusterization and classification. Hopfield nets are used for the recognition of jets occurring during the fragmentation process of the e + e - reaction. Multilayer nets are used for the whole reaction analysis. Impediments are pointed out. Associated background noise is also examined. Multilayer nets may enhance the signal to noise ratio when looking for an upper limit for the production of a Higgs boson in the expected canal, and allow for the specific study of the γ b anti b

Overview of JET results in support of the ITER physics basis

International Nuclear Information System (INIS)

Gormezano, C.

2001-01-01

The JET experimental campaign has focused on studies in support of the ITER physics basis. An overview of the results obtained is given both for the reference ITER scenario, the ELMy H-mode, and for advanced scenarios which in JET are based on Internal Transport Barriers. JET studies for the ELMy H-mode have been instrumental for the definition of ITER-FEAT. Positive elongation and current scaling in the ITER scaling law have been confirmed, but the observed density scaling fits better a two term (core and edge) model. Significant progress in neo-classical tearing mode limits has been made showing that ITER operation seems to be optimised. Effective helium pumping and divertor enrichment is found to be well within ITER requirements. Target asymmetries and H-isotope retention are well simulated by modelling codes taking into account drift flows in the scrape-off plasmas. Striking improvements in fuelling effectiveness have been found with the new high field pellet launch facility. Good progress has been made on scenarios for achieving good confinement at high densities, both with RI modes and with high field side pellets. Significant development of advanced scenarios in view of their application to ITER has been achieved. Integrated advanced scenarios are in good progress with edge pressure control (impurity radiation). An access domain has been explored showing in particular that the power threshold increases with magnetic field but can be significantly reduced when Lower Hybrid current drive is used to produce target plasma with negative shear. The role of ion pressure peaking on MHD has been well documented. Lack of sufficient additional heating power and interaction with the septum at high beta prevents assessment of beta limits (steady plasmas achieved with β N up to 2.6). Plasmas with non-inductive current (I NI /Ip=60%), well aligned with plasma current, high beta and good confinement have also been obtained. (author)

Basis-Independent Analysis of the sneutrino Sector in R-Parity Violating Supersymmetry

International Nuclear Information System (INIS)

Grossman, Yuval

2000-01-01

In R-parity-violating supersymmetric models (with a conserved baryon number), there are no quantum numbers that distinguish the lepton-doublet and down-type Higgs supermultiplets. As a result, the R-parity-violating parameters depend on the basis choice for these superfields, although physical observables are independent of the choice of basis. This paper presents a basis-independent computation of the sneutrino/antisneutrino squared-mass splitting in terms of basis-independent quantities. Techniques are developed for an arbitrary number of sneutrino generations; specific results are provided for the one, two and three generation cases

Research about the Physical Reactions to Appear in Herbal Acupuncture Operating

Directory of Open Access Journals (Sweden)

Kim Young-Ho

2003-02-01

Full Text Available Objectives : This study was done to observe the physical reactions after herbal acupuncture operating, through the questionnaire. Methods : The study group was divided into six groups that were NS group(N=20, CF group(N=22, BU group(N=23, BUM(N=19, HP group(N=20 and BV group(N=19. The herbal acupuncture was injected by 0.05ml at the Fengmen(風門:B12, Feishu(肺兪:B13, Fufen(附分:B41, Pohu(魄戶:B42 4 points. Therefore suffers recorded the existence of the symptoms on questionnaire paper which we exemplified the above symptoms on that day, in the first day, in the second day and in the seventh day. Results : The following results were obtained ; 1. General symptoms which appear in the herbal acupuncture operating were following as : pain of body partially, discomfort, pain which appear in activity and fatigue. 2. The symptoms which appear in the herbal acupuncture operating were most extreme in the first day, since then those were reduced. Conclusions : By the above results, it would be needed further research about statistically comparative-study among herbal acupunctures and alternative plans which is decreased side effect.

Improved predictions of nuclear reaction rates with the TALYS reaction code for astrophysical applications

International Nuclear Information System (INIS)

Goriely, S.; Hilaire, S.; Koning, A.J

2008-01-01

Context. Nuclear reaction rates of astrophysical applications are traditionally determined on the basis of Hauser-Feshbach reaction codes. These codes adopt a number of approximations that have never been tested, such as a simplified width fluctuation correction, the neglect of delayed or multiple-particle emission during the electromagnetic decay cascade, or the absence of the pre-equilibrium contribution at increasing incident energies. Aims. The reaction code TALYS has been recently updated to estimate the Maxwellian-averaged reaction rates that are of astrophysical relevance. These new developments enable the reaction rates to be calculated with increased accuracy and reliability and the approximations of previous codes to be investigated. Methods. The TALYS predictions for the thermonuclear rates of relevance to astrophysics are detailed and compared with those derived by widely-used codes for the same nuclear ingredients. Results. It is shown that TALYS predictions may differ significantly from those of previous codes, in particular for nuclei for which no or little nuclear data is available. The pre-equilibrium process is shown to influence the astrophysics rates of exotic neutron-rich nuclei significantly. For the first time, the Maxwellian- averaged (n, 2n) reaction rate is calculated for all nuclei and its competition with the radiative capture rate is discussed. Conclusions. The TALYS code provides a new tool to estimate all nuclear reaction rates of relevance to astrophysics with improved accuracy and reliability. (authors)

Molecular basis of the fructose-2,6-bisphosphatase reaction of PFKFB3: Transition state and the C-terminal function

International Nuclear Information System (INIS)

Cavalier, Michael C.; Kim, Song-Gun; Neau, David; Lee, Yong-Hwan

2012-01-01

The molecular basis of fructose-2,6-bisphosphatase (F-2,6-P 2 ase) of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB) was investigated using the crystal structures of the human inducible form (PFKFB3) in a phospho-enzyme intermediate state (PFKFB3-P · F-6-P), in a transition state-analogous complex (PFKFB3 · AlF 4 ), and in a complex with pyrophosphate (PFKFB3 · PP i ) at resolutions of 2.45, 2.2, and 2.3 (angstrom), respectively. Trapping the PFKFB3-P · F-6-P intermediate was achieved by flash cooling the crystal during the reaction, and the PFKFB3 · AlF 4 and PFKFB3 · PP i complexes were obtained by soaking. The PFKFB3 · AlF 4 and PFKFB3 · PP i complexes resulted in removing F-6-P from the catalytic pocket. With these structures, the structures of the Michaelis complex and the transition state were extrapolated. For both the PFKFB3-P formation and break down, the phosphoryl donor and the acceptor are located within ∼5.1 (angstrom), and the pivotal point 2-P is on the same line, suggesting an 'in-line' transfer with a direct inversion of phosphate configuration. The geometry suggests that NE2 of His253 undergoes a nucleophilic attack to form a covalent N-P bond, breaking the 2O-P bond in the substrate. The resulting high reactivity of the leaving group, 2O of F-6-P, is neutralized by a proton donated by Glu322. Negative charges on the equatorial oxygen of the transient bipyramidal phosphorane formed during the transfer are stabilized by Arg252, His387, and Asn259. The C-terminal domain (residues 440-446) was rearranged in PFKFB3 · PP i , implying that this domain plays a critical role in binding of substrate to and release of product from the F-2,6-P 2 ase catalytic pocket. These findings provide a new insight into the understanding of the phosphoryl transfer reaction.

Density Functional Study of Chemical Reaction Equilibrium for Dimerization Reactions in Slit and Cylindrical Nanopores

Czech Academy of Sciences Publication Activity Database

Malijevský, Alexandr; Lísal, Martin

2009-01-01

Roč. 130, č. 16 (2009), 164713-1-24 ISSN 0021-9606 R&D Projects: GA ČR GA203/05/0725; GA AV ČR 1ET400720507; GA AV ČR KAN400720701 Institutional research plan: CEZ:AV0Z40720504 Keywords : density functional theory * reaction ensemble Monte Carlo * reaction equilibrium Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.093, year: 2009

Physics Division annual review, 1 April 1980-31 March 1981

Energy Technology Data Exchange (ETDEWEB)

1982-06-01

Progress in nuclear physics research is reported in the following areas: medium-energy physics (pion reaction mechanisms, high-resolution studies and nuclear structure, and two-nucleon physics with pions and electrons); heavy-ion research at the tandem and superconducting linear accelerator (resonant structure in heavy-ion reactions, fusion cross sections, high angular momentum states in nuclei, and reaction mechanisms and distributions of reaction strengths); charged-particle research; neutron and photonuclear physics; theoretical physics (heavy-ion direct-reaction theory, nuclear shell theory and nuclear structure, nuclear matter and nuclear forces, intermediate-energy physics, microscopic calculations of high-energy collisions of heavy ions, and light ion direct reactions); the superconducting linac; accelerator operations; and GeV electron linac. Progress in atomic and molecular physics research is reported in the following areas: dissociation and other interactions of energetic molecular ions in solid and gaseous targets, beam-foil research and collision dynamics of heavy ions, photoionization- photoelectron research, high-resolution laser rf spectroscopy with atomic and molecular beams, moessbauer effect research, and theoretical atomic physics. Studies on interactions of energetic particles with solids are also described. Publications are listed. (WHK)

Physics Division annual review, 1 April 1980-31 March 1981

International Nuclear Information System (INIS)

1982-06-01

Progress in nuclear physics research is reported in the following areas: medium-energy physics (pion reaction mechanisms, high-resolution studies and nuclear structure, and two-nucleon physics with pions and electrons); heavy-ion research at the tandem and superconducting linear accelerator (resonant structure in heavy-ion reactions, fusion cross sections, high angular momentum states in nuclei, and reaction mechanisms and distributions of reaction strengths); charged-particle research; neutron and photonuclear physics; theoretical physics (heavy-ion direct-reaction theory, nuclear shell theory and nuclear structure, nuclear matter and nuclear forces, intermediate-energy physics, microscopic calculations of high-energy collisions of heavy ions, and light ion direct reactions); the superconducting linac; accelerator operations; and GeV electron linac. Progress in atomic and molecular physics research is reported in the following areas: dissociation and other interactions of energetic molecular ions in solid and gaseous targets, beam-foil research and collision dynamics of heavy ions, photoionization- photoelectron research, high-resolution laser rf spectroscopy with atomic and molecular beams, moessbauer effect research, and theoretical atomic physics. Studies on interactions of energetic particles with solids are also described. Publications are listed

Temperature dependence on sodium-water chemical reaction

International Nuclear Information System (INIS)

Tamura, Kenta; Deguchi, Yoshihiro; Suzuki, Koichi; Takata, Takashi; Yamaguchi, Akira; Kikuchi, Shin; Ohshima, Hiroyuki

2012-01-01

In a sodium-cooled fast reactor (SFR), liquid sodium is used as a heat transfer fluid because of its excellent heat transport capability. On the other hand, it has strong chemical reactivity with water vapor. One of the design basis accidents of the SFR is the water leakage into the liquid sodium flow by a breach of heat transfer tubes. This process ends up damages on the heat transport equipment in the SFR. Therefore, the study on sodium-water chemical reactions is of paramount importance for security reasons. This study aims to clarify the sodium-water reaction mechanisms using laser diagnostics. A quasi one-dimensional flame model is also applied to a sodium-water counter-flow reaction field. Temperature, H 2 , H 2 O, OH, Na and Particulate matter were measured using laser induced fluorescence and CARS in the counter-flow reaction field. The temperature of the reaction field was also modified to reduce the condensation of Na in the reaction zone. (author)

Pore-scale studies of multiphase flow and reaction involving CO2 sequestration in geologic formations

Science.gov (United States)

Kang, Q.; Wang, M.; Lichtner, P. C.

2008-12-01

In geologic CO2 sequestration, pore-scale interfacial phenomena ultimately govern the key processes of fluid mobility, chemical transport, adsorption, and reaction. However, spatial heterogeneity at the pore scale cannot be resolved at the continuum scale, where averaging occurs over length scales much larger than typical pore sizes. Natural porous media, such as sedimentary rocks and other geological media encountered in subsurface formations, are inherently heterogeneous. This pore-scale heterogeneity can produce variabilities in flow, transport, and reaction processes that take place within a porous medium, and can result in spatial variations in fluid velocity, aqueous concentrations, and reaction rates. Consequently, the unresolved spatial heterogeneity at the pore scale may be important for reactive transport modeling at the larger scale. In addition, current continuum models of surface complexation reactions ignore a fundamental property of physical systems, namely conservation of charge. Therefore, to better understand multiphase flow and reaction involving CO2 sequestration in geologic formations, it is necessary to quantitatively investigate the influence of the pore-scale heterogeneity on the emergent behavior at the field scale. We have applied the lattice Boltzmann method to simulating the injection of CO2 saturated brine or supercritical CO2 into geological formations at the pore scale. Multiple pore-scale processes, including advection, diffusion, homogeneous reactions among multiple aqueous species, heterogeneous reactions between the aqueous solution and minerals, ion exchange and surface complexation, as well as changes in solid and pore geometry are all taken into account. The rich pore scale information will provide a basis for upscaling to the continuum scale.

Theoretical Physics Division

International Nuclear Information System (INIS)

This report is a survey of the studies done in the Theoretical Physics Division of the Nuclear Physics Institute; the subjects studied in theoretical nuclear physics were the few-nucleon problem, nuclear structure, nuclear reactions, weak interactions, intermediate energy and high energy physics. In this last field, the subjects studied were field theory, group theory, symmetry and strong interactions [fr

Some physical magnitudes of interest for nuclear reactions and their dependence on the projectile-target system

International Nuclear Information System (INIS)

Fernandez Niello, J.O.; Pacheco, A.J.

1984-01-01

The design and analysis of experiences with heavy ions requires the knwoledge of several characteristic parameters of the collision and their dependence on the reactant system. In the case of an electrostatic accelerator as the TANDAR, the bombarding energy (function of the projectile) is a direct consequence of the evolution of the charged state distribution for the projectile at the exit of the last stripper, as a function of the atomic number. The complexity resulting from this dependence originated the confection of a series of diagrams. The diagrams correpond to the different physical magnitudes of interest in the analysis of nuclear reactions as a function of the projectile-target combination for terminal tensions similar to those expected to reach at the TANDAR. In each case, the curves are refered to the following physical magnitudes: Ecm/Bc Kinetic energy in the center of the mass system and Coulomb barrier for the projectile-target system, Lgr = angular momentum corresponding to the grazing collisions. Diagrams of the average projectile energy per nucleon for the different values of the terminal tensions with one or two solid strippers are included. The use of the diagrams in some practical applications is illustrated through four examples. The diagrams may be extended, if necesary, to other physical magnitudes, at different accelerator's operating conditions. (M.E.L.) [es

Nuclear astrophysics: An application of nuclear physics

International Nuclear Information System (INIS)

Fueloep, Z.

2005-01-01

Nuclear astrophysics, a fruitful combination of nuclear physics and astrophysics can be viewed as a special application of nuclear physics where the study of nuclei and their reactions are motivated by astrophysical problems. Nuclear astrophysics is also a good example for the state of the art interdisciplinary research. The origin of elements studied by geologists is explored by astrophysicists using nuclear reaction rates provided by the nuclear physics community. Due to the high interest in the field two recent Nuclear Physics Divisional Conferences of the European Physical Society were devoted to nuclear astrophysics and a new conference series entitled 'Nuclear Physics in Astrophysics' has been established. Selected problems of nuclear astrophysics will be presented emphasizing the interplay between nuclear physics and astrophysics. As an example the role of 14 N(p,r) 15 O reaction rate in the determination of the age of globular clusters will be discussed in details

Maillard Reaction in Natural Rubber Latex: Characterization and Physical Properties of Solid Natural Rubber

Directory of Open Access Journals (Sweden)

S. Montha

2016-01-01

Full Text Available Maillard reaction in Natural Rubber (NR latex was investigated by treating fresh NR latex with glutaraldehyde (C5H8O2 in amounts of 0, 50, 100, and 200 mmol/kg of latex. Protein cross-linking in fresh NR latex and solid NR was confirmed by using sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE and attenuated total reflection infrared (ATR-IR spectroscopy, respectively. It was found that degree of protein cross-linking in NR increased with increasing C5H8O2 concentration. Physical properties of untreated and treated NR substances in terms of gel content, initial Wallace plasticity (P0, plasticity retention index (PRI, Mooney viscosity, and tensile strength were carefully explored. Results clearly showed that the Maillard cross-linking of proteins had remarkable effect on bulk NR properties, that is, solvent resistance, hardness, resistance to oxidation, rheological behavior, and resistance to stretching out.

Feynman-Kac equations for reaction and diffusion processes

Science.gov (United States)

Hou, Ru; Deng, Weihua

2018-04-01

This paper provides a theoretical framework for deriving the forward and backward Feynman-Kac equations for the distribution of functionals of the path of a particle undergoing both diffusion and reaction processes. Once given the diffusion type and reaction rate, a specific forward or backward Feynman-Kac equation can be obtained. The results in this paper include those for normal/anomalous diffusions and reactions with linear/nonlinear rates. Using the derived equations, we apply our findings to compute some physical (experimentally measurable) statistics, including the occupation time in half-space, the first passage time, and the occupation time in half-interval with an absorbing or reflecting boundary, for the physical system with anomalous diffusion and spontaneous evanescence.

The effect of menstruation on chosen physiological and biochemical reactions caused by the physical effort with the submaximal intensity

Directory of Open Access Journals (Sweden)

P Zieliński

2003-03-01

Full Text Available The aim of this work was to determine the influence of the menstruation phase on changes of respective indicators of the gas exchange and on biochemical parameters of blood during physical efforts with the sub-maximal intensity. Fifteen female students of the Academy of Physical Education took part in the study. Girls were aged from 19 to 22 years old and did not practice sports. The effort tests were conducted in the follicular and luteal phase of two succeeding menstrual cycles. As far the aerobic capacity determination is concerned, one cyclo-ergometric test with graded effort was conducted and it was performed till the “refusal”. It allowed to mark a threshold (TDMA and a maximal level of physiological and biochemical indicators. Basing on the results of the graded test individual loads were determined for every next effort trial (repeated 4 times in every phase of the two succeeding menstrual cycles. The aim of this trial was to evaluate the reaction of women’s constitution on work with the sub-maximal intensity. The above trial consisted on two 10 min efforts divided with the 2 min pause (the first effort with the intensity of 80% of the TDMA threshold, second with the intensity bigger about 30-40% of difference between TDMA and a maximal load established by the graded test. The research did not reveal statistically significant differentiation as considering effort changes of basic physiological and biochemical indicators, determining reaction of women’s organisms on work with the sub- and over- threshold intensity (TDMA. It showed that menstruation has not significant effect on the level of changes of analysed parameters caused by the physical effort with the sub-maximal intensity.

Long-run evolution of the global economy: 1. Physical basis

Science.gov (United States)

Garrett, Timothy J.

2014-04-01

Climate change is a two-way street during the Anthropocene: civilization depends upon a favorable climate at the same time that it modifies it. Yet studies that forecast economic growth employ fundamentally different equations and assumptions than those used to model Earth's physical, chemical, and biological processes. In the interest of establishing a common theoretical framework, this article treats humanity like any other physical process; that is, as an open, nonequilibrium thermodynamic system that sustains existing circulations and furthers its material growth through the consumption and dissipation of energy. The link of physical to economic quantities comes from a prior result that establishes a fixed relationship between rates of global energy consumption and a historical accumulation of global economic wealth. What follows are nonequilibrium prognostic expressions for how wealth, energy consumption, and the Gross World Product (GWP) grow with time. This paper shows that the key components that determine whether civilization "innovates" itself toward faster economic growth include energy reserve discovery, improvements to human and infrastructure longevity, and reductions in the amount of energy required to extract raw materials. Growth slows due to a combination of prior growth, energy reserve depletion, and a "fraying" of civilization networks due to natural disasters. Theoretical and numerical arguments suggest that when growth rates approach zero, civilization becomes fragile to such externalities as natural disasters, and the risk is for an accelerating collapse.

Applications in atomic and molecular physics

International Nuclear Information System (INIS)

Todd, J.F.J.

1976-01-01

Probably the most extensive area of application of quadrupole mass spectrometry has been that of atomic and molecular physics: it was for this market that the commercial instruments were first introduced and the variety of investigations which have consequently been made possible provides an obvious basis for illustrating the unique features possessed by the mass filter. The account which follows is divided into two main sections. The first deals with general applications of the quadrupole, in which the instrument is used essentially as an analyser for neutral or ionic species, e.g. the monitoring of residual gases and reaction products. The fields of vacuum technology, surface studies and gas phase studies are considered in turn. The second section is devoted to an account of the special applications of quadrupole fields in which use is made of properties such as ion containment. (Auth.)

Progress Report. Institute of Atomic Physics, Institute of Physics and Nuclear Engineering, Department of Heavy Ion Physics. 1992-1993

International Nuclear Information System (INIS)

Grama, C.; Ionescu-Bujor, M.; Poenaru, D.; Pop, A.

1994-01-01

A brief account of the research and development activities carried out in the Department of Heavy Ion Physics, Institute of Atomic Physics, Institute of Physics and Nuclear Engineering, Bucharest, during the period January 1992 to December 1993 is presented. The main topics concern nuclear structure models and methods, heavy-ion-induced reactions, and general properties of nuclei and nuclear energy levels. Also, works dealing with particle detection, measuring instruments and methods are reported. The report contains two sections. The first covers the research in progress in the fields of nuclear structure, nuclear reactions, atomic physics, accelerator, instrumentation, methods and computer codes. The second one, the appendix, contains the list of publications of the Department staff in journals and proceedings, books, and preprints, the conference contributions, the academic degrees awarded, the scientific exchanges, and the list of scientific personnel

Nuclear reactions video (knowledge base on low energy nuclear physics)

International Nuclear Information System (INIS)

Zagrebaev, V.; Kozhin, A.

1999-01-01

The NRV (nuclear reactions video) is an open and permanently extended global system of management and graphical representation of nuclear data and video-graphic computer simulation of low energy nuclear dynamics. It consists of a complete and renewed nuclear database and well known theoretical models of low energy nuclear reactions altogether forming the 'low energy nuclear knowledge base'. The NRV solves two main problems: 1) fast and visualized obtaining and processing experimental data on nuclear structure and nuclear reactions; 2) possibility for any inexperienced user to analyze experimental data within reliable commonly used models of nuclear dynamics. The system is based on the realization of the following principal things: the net and code compatibility with the main existing nuclear databases; maximal simplicity in handling: extended menu, friendly graphical interface, hypertext description of the models, and so on; maximal visualization of input data, dynamics of studied processes and final results by means of real three-dimensional images, plots, tables and formulas and a three-dimensional animation. All the codes are composed as the real Windows applications and work under Windows 95/NT

Physical chemistry of the chlorination reactions of metals and alloys

International Nuclear Information System (INIS)

De Micco, Georgina

2007-01-01

This thesis has contributed towards the knowledge of complex systems.The chlorination reactions are non-catalytic solid-gas heterogeneous reactions which, in addition to the difficulties associated with the reactions occurring in an interface, have the particular features of chlorides compounds and their interactions.The questions arising from this type of study can not be solved by the application of an individual analysis technique.From the experimental point of view it is complicated, and many instrumental techniques need to be applied in order to obtain significant results as well as meaningful interpretations.The system under study is the chlorination of ternary and binary alloys containing Al, Cu and Zn and the pure metals, as these elements belong to the spent nuclear fuel cladding.The aim of the research has been to develop a process that eliminates most of the aluminium, which is the more abundant specie. In this way, the amount of material to be conditioned (vitrified) is reduced.The objectives proposed for each system have been achieved, and the results obtained can also be applied to similar systems for metal recycling [es

Structural Basis for Target Protein Regcognition by Thiredoxin

DEFF Research Database (Denmark)

Maeda, Kenji

2007-01-01

Ser) and a mutant of an in vitro substrate alpha-amylase/subtilisin inhibitor (BASI) (Cys144Ser), as a reaction intermediate-mimic of Trx-catalyzed disulfide reduction. The resultant structure showed a sequence of BASI residues along a conserved hydrophobic groove constituted of three loop segments...... of Trx-fold proteins glutaredoxin and glutathione transferase. This study suggests that the features of main chain conformation as well as charge property around disulfide bonds in protein substrates are important factors for interaction with Trx. Moreover, this study describes a detailed structural......Thioredoxin (Trx) is an ubiquitous protein disulfide reductase that possesses two redox active cysteines in the conserved active site sequence motif, Trp-CysN-Gly/Pro-Pro-CysC situated in the so called Trx-fold. The lack of insight into the protein substrate recognition mechanism of Trx has to date...

Large local reactions to insect envenomation.

Science.gov (United States)

Carlson, John; Golden, David B K

2016-08-01

Insect stings often induce large local reactions (LLRs) that result in morbidity. These reactions do have an immunologic basis; however, patients presenting with LLRs should be managed differently than those with systemic allergic reactions, as described in this review. Morbidity results from the inflammation itself along with the iatrogenic consequences of treatment. The prescription of antihistamine medications and the use of antibiotics are generally not indicated for patients with LLRs because of the risks/side-effects of these medications and the low probability of benefit. Some patients are also concerned over the possibility that a future sting will evolve into a life-threatening reaction. Although these reactions do involve IgE, patients are not at sufficient risk to warrant prescription of autoinjectable epinephrine. Venom-specific immunotherapy can be considered when LLRs are frequent and associated with significant impairment. Clinicians can reduce morbidity from LLRs by reassuring the patients, avoiding medications that result in side-effects when they are not indicated, and referring to an allergist when there are additional concerns, such as frequent impairment.

Microscopic calculation of friction coefficients for use in heavy-ion reaction

International Nuclear Information System (INIS)

Iwamoto, A.; Harada, K.; Yoshida, S.

1981-01-01

A microscopic calculation has been done for the friction coefficient for use in the deep-inelastic collision of heavy nuclei. We adopted the formalism of the linear response theory as a basis and used the adiabatic base of the two-center shell model. Several reaction channels with the total mass numbers of 236 and 260 systems were investigated. The friction coefficients for the radial and deforming motions including the coupling term were calculated as a function of the distance between two nuclei and deformation of the two nuclei for each channel. The general feature of the friction coefficient, its strength and form factor, was clarified in this model and comparison with the results of other models were done. It was found that our model gives a physically plausible value for the friction coefficient as a whole. (orig.)

[Mechanism of reaction catalyzed by RNA-ligase from bacteriophage T4].

Science.gov (United States)

Zagrebel'nyĭ, S N; Zernov, Iu P

1987-01-01

The dissociation constants of the complexes of RNA-ligase with acceptors, donors and the adenylylated donor A(5')ppAp have been determined on the basis of the inhibition of ATP-pyrophosphate exchange reaction. The dissociation constants of the complexes of the enzyme with "poor" acceptors (oligouridilates) have been shown to be slightly different from those with "good" acceptors (oligoadenylates). The dependence of the reaction velocity of the formation of ligation products on the concentration of acceptors (pA)4, (pU)4 and the adenylylated donor A(5)ppAp has been studied. On the basis of the data obtained the conclusion about the random addition mechanism has been drawn. The reaction takes place in the steady-state conditions in the case of (pA)4 and in the equilibrium conditions--in the case of (pU)4.

Uranium Metal Reaction Behavior in Water, Sludge, and Grout Matrices

Energy Technology Data Exchange (ETDEWEB)

Delegard, Calvin H.; Schmidt, Andrew J.

2009-05-27

This report summarizes information and data on the reaction behavior of uranium metal in water, in water-saturated simulated and genuine K Basin sludge, and in grout matrices. This information and data are used to establish the technical basis for metallic uranium reaction behavior for the K Basin Sludge Treatment Project (STP). The specific objective of this report is to consolidate the various sources of information into a concise document to serve as a high-level reference and road map for customers, regulators, and interested parties outside the STP (e.g., external reviewers, other DOE sites) to clearly understand the current basis for the corrosion of uranium metal in water, sludge, and grout.

Uranium Metal Reaction Behavior in Water, Sludge, and Grout Matrices

Energy Technology Data Exchange (ETDEWEB)

Delegard, Calvin H.; Schmidt, Andrew J.

2008-09-25

This report summarizes information and data on the reaction behavior of uranium metal in water, in water-saturated simulated and genuine K Basin sludge, and in grout matrices. This information and data are used to establish the technical basis for metallic uranium reaction behavior for the K Basin Sludge Treatment Project (STP). The specific objective of this report is to consolidate the various sources of information into a concise document to serve as a high-level reference and road map for customers, regulators, and interested parties outside the STP (e.g., external reviewers, other DOE sites) to clearly understand the current basis for the corrosion of uranium metal in water, sludge, and grout.

Annual report 1977, Particle physics, Institute of Physics, University of Stockholm

International Nuclear Information System (INIS)

1978-01-01

The research in the field of elementary particle physics concerns hadronic processes at high energies, using the facilities offered by CERN and Fermilab, USA. The teams carrying out experiments with bubble chambers are mainly working at the institute, whereas the tems utilizing counter techniques spend long periods at CERN. Experiments at CERN SPS and Fermilab are in progress. The equipment for bubble chamber physics at the institute consists of five scanning tables, one manual measuring machine and the Spiral Reader measuring machine. A computer CD 6400 is available at the institute. The research program comprises study of 100 GeV/c antiproton-deuterium reactions, 12 GeV/c antiproton-deuterium reactions, 9 and 12 GeV/c antiproton-proton reactions studying all annihilation and non-annihilation processes, a detailed study of amplitudes in 4 GeV/c π - p reactions with strange particles, strange particle production in 19 GeV/c pp and study of 19 GeV/c pd. The main emphasis in the future will be on experiments with the European Hybrid Spectrometer system and the Big European Bubble Chamber at SPS. The group participates in the design work and planning for the physics experiments. Research physicists from the group participate in counter experiments at SPS studying elastic scattering at high transverse momenta, elastic scattering of π, K and p sup(+-) at PS energies and study of line reversal invariance in πp and Kp reactions. (author)

Inertial effects in diffusion-limited reactions

International Nuclear Information System (INIS)

Dorsaz, N; Foffi, G; De Michele, C; Piazza, F

2010-01-01

Diffusion-limited reactions are commonly found in biochemical processes such as enzyme catalysis, colloid and protein aggregation and binding between different macromolecules in cells. Usually, such reactions are modeled within the Smoluchowski framework by considering purely diffusive boundary problems. However, inertial effects are not always negligible in real biological or physical media on typical observation time frames. This is all the more so for non-bulk phenomena involving physical boundaries, that introduce additional time and space constraints. In this paper, we present and test a novel numerical scheme, based on event-driven Brownian dynamics, that allows us to explore a wide range of velocity relaxation times, from the purely diffusive case to the underdamped regime. We show that our algorithm perfectly reproduces the solution of the Fokker-Planck problem with absorbing boundary conditions in all the regimes considered and is thus a good tool for studying diffusion-guided reactions in complex biological environments.

Structural basis for target protein recognition by the protein disulfide reductase thioredoxin

DEFF Research Database (Denmark)

Maeda, Kenji; Hägglund, Per; Finnie, Christine

2006-01-01

Thioredoxin is ubiquitous and regulates various target proteins through disulfide bond reduction. We report the structure of thioredoxin (HvTrxh2 from barley) in a reaction intermediate complex with a protein substrate, barley alpha-amylase/subtilisin inhibitor (BASI). The crystal structure...... of this mixed disulfide shows a conserved hydrophobic motif in thioredoxin interacting with a sequence of residues from BASI through van der Waals contacts and backbone-backbone hydrogen bonds. The observed structural complementarity suggests that the recognition of features around protein disulfides plays...... a major role in the specificity and protein disulfide reductase activity of thioredoxin. This novel insight into the function of thioredoxin constitutes a basis for comprehensive understanding of its biological role. Moreover, comparison with structurally related proteins shows that thioredoxin shares...

Spallation reactions studied with 4-detector arrays

Indian Academy of Sciences (India)

Recently there has been a renewed interest in the study of spallation reactions in basic nuclear physics as well as in potential applications. Spallation reactions induced by light projectiles (protons, antiprotons, pions, etc.) in the GeV range allow the formation of hot nuclei which do not suffer the collective excitations ...

Solar nuclear reactions

Energy Technology Data Exchange (ETDEWEB)

Kocharov, G

1978-04-01

The current state of neutrino solar astrophysics is outlined, showing the contradictions between the experimental results of solar neutrino detection and the standard solar models constructed on the basis of the star structure and development theory, which give values for high-energy neutrino fluxes considerably exceeding the upper experimental limit. A number of hypotheses interpreting the experimental results are summarized. The hypotheses are critically assessed and experiments are recommended for refining or verifying experimental data. Also dealt with are nuclear reactions in the Sun, as is the attempt to interpret the anomalous by high /sup 3/He fluxes from the Sun and the relatively small amounts of solar neutrinos and gamma quanta. The importance is emphasized of the simultaneous and complex measurement of the fluxes of neutrons, gamma radiation, and isotopes of hydrogen, helium, and boron from the Sun as indicators of nuclear reactions in the Sun.

Structure of fungal oxyluciferin, the product of the bioluminescence reaction.

Science.gov (United States)

Purtov, K V; Osipova, Z M; Petushkov, V N; Rodionova, N S; Tsarkova, A S; Kotlobay, A A; Chepurnykh, T V; Gorokhovatsky, A Yu; Yampolsky, I V; Gitelson, J I

2017-11-01

The structure of fungal oxyluciferin was determined, the enzymatic bioluminescence reaction under substrate saturation conditions with discrete monitoring of formed products was conducted, and the structures of the end products of the reaction were established. On the basis of these studies, the scheme of oxyluciferin degradation to the end products was developed. The structure of fungal oxyluciferin was confirmed by counter synthesis.

Finnish Cooperating Physics Teachers' Conceptions of Physics Teachers' Teacher Knowledge

Science.gov (United States)

Asikainen, Mervi A.; Hirvonen, Pekka E.

2010-01-01

This article examines Finnish cooperating physics teachers' conceptions of teacher knowledge in physics. Six experienced teachers were interviewed. The data was analyzed to form categories concerning the basis of teacher knowledge, and the tradition of German Didaktik and Shulman's theory of teacher knowledge were used in order to understand the…

Kaon-nucleus reactions and hypernuclei

International Nuclear Information System (INIS)

Dover, C.B.

1987-01-01

Recent advances in hypernuclear physics and kaon-nucleus scattering are discussed, with emphasis on the spectroscopy of Λ single particle states in heavy systems, as revealed by the (π + ,K + ) reaction. 26 refs., 8 figs

Investigation of Na-CO2 Reaction with Initial Reaction in Various Reacting Surface

International Nuclear Information System (INIS)

Kim, Hyun Su; Park, Gunyeop; Kim, Soo Jae; Park, Hyun Sun; Kim, Moo Hwan; Wi, Myung-Hwan

2015-01-01

The reaction products that cause oxidation and erosion are threaten the heat transfer tubes so that it is necessary to investigate Na-CO 2 reaction according to various experimental parameter. Unlike SWR, Na-CO 2 reaction is more complex to deal with reaction kinetics. Since a comprehensive understanding of Na-CO 2 reaction mechanism is crucial for the safety analysis, the reaction phenomenon under the various conditions was investigated. The current issue is to make a database for developing computational code for CO 2 gas leak situation because it is experimentally difficult to analyze the actual accident situation. Most studies on Na-CO 2 interaction reports that chemical reaction is getting vigorous as temperature increased and reactivity is sensitive as temperature change between 400 .deg. C and 600 .deg. C. Therefore, temperature range is determined based on the operating condition (450 - 500 .deg. C) of KALIMER-600 employed as supercritical CO 2 brayton cycle energy conversion system for Na-CO 2 heat exchanger. And next parameter is sodium surface area which contact between sodium and CO 2 when CO 2 is injected into sodium pool in the accident situation. So, the fundamental surface reaction is experimentally studied in the range of 8 - 12cm 2 . Additionally, it has been reported in recent years that CO 2 Flow rate affects reactivity less significantly and CO 2 flow rate is assumed that 5 SLPM (standard liter per minute) is suitable as a basis for a small leakage. The finally selected control parameters is sodium temperature and reacting surface area with constant CO 2 flow rate. Na-CO 2 reaction test is performed for investigating risk of potential accident which contacts with liquid sodium and CO 2 . Amount of reaction is saturated as time passed because of kept a balance between production of solid phase reaction products and amount of diffusivity. These results contribute to make a database for the SFR safety analysis and additional experiments are needed

Reaction-rate formula in out of equilibrium quantum field theory

OpenAIRE

Niegawa, A.; Okano, K.; Ozaki, H.

1999-01-01

A complete derivation, from first principles, of the reaction-rate formula for a generic reaction taking place in an out of equilibrium quantum-field system is given. It is shown that the formula involves no finite-volume correction. Each term of the reaction-rate formula represents a set of physical processes that contribute to the reaction under consideration.

Learning to predict chemical reactions.

Science.gov (United States)

Kayala, Matthew A; Azencott, Chloé-Agathe; Chen, Jonathan H; Baldi, Pierre

2011-09-26

Being able to predict the course of arbitrary chemical reactions is essential to the theory and applications of organic chemistry. Approaches to the reaction prediction problems can be organized around three poles corresponding to: (1) physical laws; (2) rule-based expert systems; and (3) inductive machine learning. Previous approaches at these poles, respectively, are not high throughput, are not generalizable or scalable, and lack sufficient data and structure to be implemented. We propose a new approach to reaction prediction utilizing elements from each pole. Using a physically inspired conceptualization, we describe single mechanistic reactions as interactions between coarse approximations of molecular orbitals (MOs) and use topological and physicochemical attributes as descriptors. Using an existing rule-based system (Reaction Explorer), we derive a restricted chemistry data set consisting of 1630 full multistep reactions with 2358 distinct starting materials and intermediates, associated with 2989 productive mechanistic steps and 6.14 million unproductive mechanistic steps. And from machine learning, we pose identifying productive mechanistic steps as a statistical ranking, information retrieval problem: given a set of reactants and a description of conditions, learn a ranking model over potential filled-to-unfilled MO interactions such that the top-ranked mechanistic steps yield the major products. The machine learning implementation follows a two-stage approach, in which we first train atom level reactivity filters to prune 94.00% of nonproductive reactions with a 0.01% error rate. Then, we train an ensemble of ranking models on pairs of interacting MOs to learn a relative productivity function over mechanistic steps in a given system. Without the use of explicit transformation patterns, the ensemble perfectly ranks the productive mechanism at the top 89.05% of the time, rising to 99.86% of the time when the top four are considered. Furthermore, the system

Learning to Predict Chemical Reactions

Science.gov (United States)

Kayala, Matthew A.; Azencott, Chloé-Agathe; Chen, Jonathan H.

2011-01-01

Being able to predict the course of arbitrary chemical reactions is essential to the theory and applications of organic chemistry. Approaches to the reaction prediction problems can be organized around three poles corresponding to: (1) physical laws; (2) rule-based expert systems; and (3) inductive machine learning. Previous approaches at these poles respectively are not high-throughput, are not generalizable or scalable, or lack sufficient data and structure to be implemented. We propose a new approach to reaction prediction utilizing elements from each pole. Using a physically inspired conceptualization, we describe single mechanistic reactions as interactions between coarse approximations of molecular orbitals (MOs) and use topological and physicochemical attributes as descriptors. Using an existing rule-based system (Reaction Explorer), we derive a restricted chemistry dataset consisting of 1630 full multi-step reactions with 2358 distinct starting materials and intermediates, associated with 2989 productive mechanistic steps and 6.14 million unproductive mechanistic steps. And from machine learning, we pose identifying productive mechanistic steps as a statistical ranking, information retrieval, problem: given a set of reactants and a description of conditions, learn a ranking model over potential filled-to-unfilled MO interactions such that the top ranked mechanistic steps yield the major products. The machine learning implementation follows a two-stage approach, in which we first train atom level reactivity filters to prune 94.00% of non-productive reactions with a 0.01% error rate. Then, we train an ensemble of ranking models on pairs of interacting MOs to learn a relative productivity function over mechanistic steps in a given system. Without the use of explicit transformation patterns, the ensemble perfectly ranks the productive mechanism at the top 89.05% of the time, rising to 99.86% of the time when the top four are considered. Furthermore, the system

Probing reaction dynamics with GDR decay

International Nuclear Information System (INIS)

Beene, J.R.

1994-01-01

The giant dipole resonance (GDR) has been a prolific source of information on the physics of the nucleus. Mostly it has taught us about nuclear structure, but recently experiments have utilized the GDR as a probe of nuclear reaction dynamics. In this report two examples of such investigations are discussed involving very different reactions and probing time scales that differ by a factor of ∼10 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.

Bridge between bound state and reaction effective nucleon–nucleon ...

Indian Academy of Sciences (India)

Y R WAGHMARE. Department of Physics, University of Pune, Pune 411 007, India ... Effective nucleon–nucleon interactions; heavy-ion reactions; microscopic approach; fu- sion reactions. .... [2] M K Pal, private communication. [3] S Godre and ...

Nonlinear many-body reaction theories from nuclear mean field approximations

International Nuclear Information System (INIS)

Griffin, J.J.

1983-01-01

Several methods of utilizing nonlinear mean field propagation in time to describe nuclear reaction have been studied. The property of physical asymptoticity is analyzed in this paper, which guarantees that the prediction by a reaction theory for the physical measurement of internal fragment properties shall not depend upon the precise location of the measuring apparatus. The physical asymptoticity is guaranteed in the Schroedinger collision theory of a scuttering system with translationally invariant interaction by the constancy of the S-matrix elements and by the translational invariance of the internal motion for well-separated fragments. Both conditions are necessary for the physical asymptoticity. The channel asymptotic single-determinantal propagation can be described by the Dirac-TDHF (time dependent Hartree-Fock) time evolution. A new asymptotic Hartree-Fock stationary phase (AHFSP) description together with the S-matrix time-dependent Hartree-Fock (TD-S-HF) theory constitute the second example of a physically asymptotic nonlinear many-body reaction theory. A review of nonlinear mean field many-body reaction theories shows that initial value TDHF is non-asymptotic. The TD-S-HF theory is asymptotic by the construction. The gauge invariant periodic quantized solution of the exact Schroedinger problem has been considered to test whether it includes all of the exact eigenfunctions as it ought to. It did, but included as well an infinity of all spurions solutions. (Kato, T.)

Nuclear reactions. An introduction

Energy Technology Data Exchange (ETDEWEB)

Paetz gen. Schieck, Hans [Koeln Univ. (Germany). Inst. fuer Kernphysik

2014-03-01

Modern, self-contained introduction to the subject matter. Emphasizes the interplay between theory and experiment. Course-tested tutorial style, contains many derivations. Nuclei and nuclear reactions offer a unique setting for investigating three (and in some cases even all four) of the fundamental forces in nature. Nuclei have been shown - mainly by performing scattering experiments with electrons, muons, and neutrinos - to be extended objects with complex internal structures: constituent quarks; gluons, whose exchange binds the quarks together; sea-quarks, the ubiquitous virtual quark-antiquark pairs and, last but not least, clouds of virtual mesons, surrounding an inner nuclear region, their exchange being the source of the nucleon-nucleon interaction. The interplay between the (mostly attractive) hadronic nucleon-nucleon interaction and the repulsive Coulomb force is responsible for the existence of nuclei; their degree of stability, expressed in the details and limits of the chart of nuclides; their rich structure and the variety of their interactions. Despite the impressive successes of the classical nuclear models and of ab-initio approaches, there is clearly no end in sight for either theoretical or experimental developments as shown e.g. by the recent need to introduce more sophisticated three-body interactions to account for an improved picture of nuclear structure and reactions. Yet, it turns out that the internal structure of the nucleons has comparatively little influence on the behavior of the nucleons in nuclei, and nuclear physics - especially nuclear structure and reactions - is thus a field of science in its own right, without much recourse to subnuclear degrees of freedom. This book collects essential material that was presented in the form of lectures notes in nuclear physics courses for graduate students at the University of Cologne. It follows the course's approach, conveying the subject matter by combining experimental facts and

Nuclear reactions. An introduction

International Nuclear Information System (INIS)

Paetz gen. Schieck, Hans

2014-01-01

Modern, self-contained introduction to the subject matter. Emphasizes the interplay between theory and experiment. Course-tested tutorial style, contains many derivations. Nuclei and nuclear reactions offer a unique setting for investigating three (and in some cases even all four) of the fundamental forces in nature. Nuclei have been shown - mainly by performing scattering experiments with electrons, muons, and neutrinos - to be extended objects with complex internal structures: constituent quarks; gluons, whose exchange binds the quarks together; sea-quarks, the ubiquitous virtual quark-antiquark pairs and, last but not least, clouds of virtual mesons, surrounding an inner nuclear region, their exchange being the source of the nucleon-nucleon interaction. The interplay between the (mostly attractive) hadronic nucleon-nucleon interaction and the repulsive Coulomb force is responsible for the existence of nuclei; their degree of stability, expressed in the details and limits of the chart of nuclides; their rich structure and the variety of their interactions. Despite the impressive successes of the classical nuclear models and of ab-initio approaches, there is clearly no end in sight for either theoretical or experimental developments as shown e.g. by the recent need to introduce more sophisticated three-body interactions to account for an improved picture of nuclear structure and reactions. Yet, it turns out that the internal structure of the nucleons has comparatively little influence on the behavior of the nucleons in nuclei, and nuclear physics - especially nuclear structure and reactions - is thus a field of science in its own right, without much recourse to subnuclear degrees of freedom. This book collects essential material that was presented in the form of lectures notes in nuclear physics courses for graduate students at the University of Cologne. It follows the course's approach, conveying the subject matter by combining experimental facts and experimental

Polymer-silica hybrids for separation of CO2 and catalysis of organic reactions

Science.gov (United States)

Silva Mojica, Ernesto

Porous materials comprising polymeric and inorganic segments have attracted interest from the scientific community due to their unique properties and functionalities. The physical and chemical characteristics of these materials can be effectively exploited for adsorption applications. This dissertation covers the experimental techniques for fabrication of poly(vinyl alcohol) (PVA) and silica (SiO2) porous supports, and their functionalization with polyamines for developing adsorbents with potential applications in separation of CO2 and catalysis of organic reactions. The supports were synthesized by processes involving (i) covalent cross-linking of PVA, (ii) hydrolysis and poly-condensation of silica precursors (i,e,. sol-gel synthesis), and formation of porous structures via (iii) direct templating and (iv) phase inversion techniques. Their physical structure was controlled by the proper combination of the preparation procedures, which resulted in micro-structured porous materials in the form of micro-particles, membranes, and pellets. Their adsorption characteristics were tailored by functionalization with polyethyleneimine (PEI), and their physicochemical properties were characterized by vibrational spectroscopy (FTIR, UV-vis), microscopy (SEM), calorimetry (TGA, DSC), and adsorption techniques (BET, step-switch adsorption). Spectroscopic investigations of the interfacial cross-linking reactions of PEI and PVA with glutaraldehyde (GA) revealed that PEI catalyzes the cross-linking reactions of PVA in absence of external acid catalysts. In-situ IR spectroscopy coupled with a focal plane array (FPA) image detector allowed the characterization of a gradient interface on a PEI/PVA composite membrane and the investigation of the cross-linking reactions as a function of time and position. The results served as a basis to postulate possible intermediates, and propose the reaction mechanisms. The formulation of amine-functionalized CO2 capture sorbents was based on the

Statistical theory of precompound nuclear reactions

International Nuclear Information System (INIS)

Nishioka, H.

1986-01-01

The purpose of the paper is to show the application of the Grassmann-integration method (or the graded-symmetry method) to a pre-equilibrium process in nuclear reactions. The Grassmann-integration method for random systems was first introduced by Efetov and later largely extended and applied to nuclear physics by Verbaarschot, Weidenmuller and Zirnbauer (referred to as VWZ). They have applied it to the equilibrium nuclear reactions; namely; the compound-nucleus reactions. It will be shown in this paper that this method is also applicable to non-equilibrium nuclear reactions. Applying this method to precompound nuclear reactions, the authors have obtained the same expression of the cross-section as Agassi, Weidenmuller and Mantzouranis (referred to as AWM) in the weak-coupling limit. In the general case their results show an important modification to AWM

Basis of the nuclear magnetic resonance

International Nuclear Information System (INIS)

Bahceli, S.

1996-08-01

The aim of this book which is translated from English language is to explain the physical and mathematical basis of nuclear magnetic resonance (NMR). There are nine chapters covering different aspects of NMR. In the firs chapter fundamental concepts of quantum mechanics are given at a level suitable for readers to understand NMR fully. The remaining chapters discuss the magnetic properties of nucleus, the interactions between atoms and molecules, continuous wave NMR, pulsed NMR, nuclear magnetic relaxation and NMR of liquids

Solid polymer electrolyte on the basis of polyethylene carbonate-lithium perchlorate system

International Nuclear Information System (INIS)

Dukhanin, G.P.; Dumler, S.A.; Sablin, A.N.; Novakov, I.A.

2009-01-01

Reaction in the system polyethylene carbonate-lithium perchlorate was investigated by IR spectroscopy, differential thermal and X-ray structural analyses. Specific electric conductivity of the prepared composition has been measured. Solid polymer electrolytes on the basis of polyethylene carbonate have conducting properties as electrolytes on the basis of unmodified polyethylene oxide. Compositions of polyethylene carbonate : LiClO 4 =10 : 1Al 2 O 3 -ZrO 2 possess maximum value of electrical conductivity. Activation energies of the process is calculated for all investigated compositions, and dependence of these values from concentration of lithium perchlorate is established

Theoretical Study of Sodium-Water Surface Reaction Mechanism

Science.gov (United States)

Kikuchi, Shin; Kurihara, Akikazu; Ohshima, Hiroyuki; Hashimoto, Kenro

Computational study of the sodium-water reaction at the gas (water) - liquid (sodium) interface has been carried out using the ab initio (first-principle) method. A possible reaction channel has been identified for the stepwise OH bond dissociations of a single water molecule. The energetics including the binding energy of a water molecule on the sodium surface, the activation energies of the bond cleavages, and the reaction energies, have been evaluated, and the rate constants of the first and second OH bond-breakings have been compared. It was found that the estimated rate constant of the former was much larger than the latter. The results are the basis for constructing the chemical reaction model used in a multi-dimensional sodium-water reaction code, SERAPHIM, being developed by Japan Atomic Energy Agency (JAEA) toward the safety assessment of the steam generator (SG) in a sodium-cooled fast reactor (SFR).

Theoretical study of sodium-water surface reaction mechanism

International Nuclear Information System (INIS)

Kikuchi, Shin; Kurihara, Akikazu; Ohshima, Hiroyuki; Hashimoto, Kenro

2012-01-01

Computational study of the sodium-water reaction at the gas (water) - liquid (sodium) interface has been carried out using the ab initio (first-principle) method. A possible reaction channel has been identified for the stepwise OH bond dissociations of a single water molecule. The energetics including the binding energy of a water molecule on the sodium surface, the activation energies of the bond cleavages, and the reaction energies, have been evaluated, and the rate constants of the first and second OH bond-breakings have been compared. It was found that the estimated rate constant of the former was much larger than the latter. The results are the basis for constructing the chemical reaction model used in a multi-dimensional sodium-water reaction code, SERAPHIM, being developed by Japan Atomic Energy Agency (JAEA) toward the safety assessment of the steam generator (SG) in a sodium-cooled fast reactor (SFR). (author)

Nuclear Physics Department annual report

International Nuclear Information System (INIS)

1997-07-01

This annual report presents articles and abstracts published in foreign journals, covering the following subjects: nuclear structure, nuclear reactions, applied physics, instrumentation, nonlinear phenomena and high energy physics

The Physical Basis of Lg Generation by Explosion Sources

Energy Technology Data Exchange (ETDEWEB)

J. L. Stevens; G. E. Baker; H. Xu; T. J. Bennett; N. Rimer; S. D. Day

2004-12-20

The goal of this project has been to develop a quantitative predictive capability for explosion-generated Lg phases with a sound and unambiguous physical basis. The research program consisted of a theoretical investigation of explosion-generated Lg combined with an observational study. The specific question addressed by this research program is how the Lg phase is generated by underground nuclear explosions. This question is fundamental to how Lg phases are interpreted for use in explosion yield estimation and earthquake/explosion discrimination. To constrain modeling, we have extensively reviewed the existing literature and complemented that work with an examination of several explosion data sets, most notably: (1) Degelen Mountain explosions recorded between 7 and 57 km, with corresponding recordings at Borovoye, at approximately 650 km; (2) recordings from Russian deep seismic sounding experiments; (3) NTS explosion sources including the NPE and nuclear tests covering a range of source depths and media properties. A simple point explosion in an infinite medium generates no shear waves, so the Lg phase is generated entirely by non-spherical components of the source and conversions through reflections and scattering. We find that the most important contributors to the Lg phase are: (1) P to S conversion at the free surface and other near source interfaces, (2) S waves generated directly by a realistically distributed explosion source including nonlinear effects due to the free surface and gravity, and (3) Rg scattering to Lg. Additional effects that contribute significantly to Lg are scattering of converted S phases that traps more of the converted P-to-S in the crust, and randomization of the components of Lg. The pS phase from a spherically symmetric explosion source in media with P-wave velocity less than upper mantle S-wave velocity is trapped in the crust and can explain the observed radial and vertical Lg. The free surface pS converted phase from the same

New physics and paradox

International Nuclear Information System (INIS)

Van der Spuy, E.

1983-01-01

Conflict between the finite and infinite in theoretical physics often results in paradox. By measuring phenomena for which such conflict exists, physicists may be able to discover in each case the basis of the conflict and thus may eventually reformulate physical laws

Strangeness nuclear physics

International Nuclear Information System (INIS)

Imai, Kenichi

1999-01-01

A simple review of strangeness nuclear physics is stated in the order of introduction, generation, structure and decay of hyper-nucleus and S=-2 nuclear physics. Strangeness nuclear physics investigate the structure and nuclear force of new created nucleus by introducing strangeness to the nuclear matter. The fundamental problems are hyperon-nucleon and hyperon-hyperon interaction. There are many methods to generate hyper nucleus. The stopped K - reaction is the best one. Λ and S hyper and S=-2 nucleus were generated by (K - , π) and (π + , K + ) reaction, (K - , π) reaction and (K - , K + ) reaction, respectively. The elementary decay process in the nucleus is Λ - > pπ (Q=38 MeV), nπ 0 and Λp - > np (Q=176 MeV), Λn- > nn. In emulsion, mass of light nucleus less than 160 were determined. Two measurement units are stated. One of them is a double focusing type K beam line in BNL to investigate H dibaryon by (K - , K + ) reaction. The other is KEK-SKS, which is superconducting kaon spectrometer to study hyper nucleus by (π + , K + ) reaction. The various kinds of binding energy of Λ single-particle states are displayed as a function of A -2/3 . These experimental data fit well with DWIA calculation using Woods-Saxon type one-body potential. A spectrum of 12C (π + , K + ) reaction showed small peak without main two peaks, which was a hyperfine structure between the exited state of 11 C core and couple of s 1/2 Λ. Although γ-ray was detected by three nucleuses such as 4 HΛ, 7 Li Λ and 9 Be Λ , γ-ray spectrometry of hyper nucleus remains unexplored. E hyper nucleus is detected by 4He(K-, t) and not by 4 He (K - , π + ). The binding energy of 4He Σ is 4.4 + 1 MeV and the width 7.0 + 0.7 MeV. Λ hyper nucleus decay is occurred by weak interaction. The elementary processes are a mesonic decay of Λ - > pπ - and Λ - > nπ 0 and a nonmesonic decay of Λn - > nn and Λp- > np. The lifetime of hyper nucleus is shorter than free Λ. Subject of S=-2 nuclear

Proton-transfer reactions in ionized gases

International Nuclear Information System (INIS)

Stiller, W.; Schmidt, R.; Schuster, R.

1985-01-01

Ion-molecule reactions play an important role in various radiolytic processes, e.g. gas-pulse radiolysis, environmental research. For a discussion of mechanisms rate coefficients have to be assessed. Here gas-phase rate coefficients of ion-(polar) molecule reactions are calculated using the ideas of interaction potentials, reactive cross-sections and distribution functions of the translational energies of both the reactants (ions I, molecules M). The starting point of our approach, directed especially to gas-phase proton-transfer reactions, is the idea that the rate coefficient k can be calculated as an ion-molecule capture-rate coefficient multiplied by a 'steric factor' representing the probability for proton transfer. Mutual capture of the reaction partners within a possible reaction zone is caused by the physical interaction between an ion and a polar molecule. A model is discussed. Results are presented. (author)

A chemical reaction in the movie The Ten Commandments

Directory of Open Access Journals (Sweden)

López Pérez, José Pedro;

2012-04-01

Full Text Available The study of natural sciences in the second year of Secondary Education must be complemented with a visit to the laboratory, where experiments should be permormed. The curriculum emphasizes the initial basis of Chemistry and the study of reactions. In this paper we describe a laboratory experience, useful for understanding the concept of chemical change. Also, we present the hypothesis that a chemical reaction was used in the classic movie The Ten Commandments.

Asian collaboration on nuclear reaction data compilation

International Nuclear Information System (INIS)

Aikawa, Masayuki; Furutachi, Naoya; Kato, Kiyoshi; Makinaga, Ayano; Devi, Vidya; Ichinkhorloo, Dagvadorj; Odsuren, Myagmarjav; Tsubakihara, Kohsuke; Katayama, Toshiyuki; Otuka, Naohiko

2013-01-01

Nuclear reaction data are essential for research and development in nuclear engineering, radiation therapy, nuclear physics and astrophysics. Experimental data must be compiled in a database and be accessible to nuclear data users. One of the nuclear reaction databases is the EXFOR database maintained by the International Network of Nuclear Reaction Data Centres (NRDC) under the auspices of the International Atomic Energy Agency. Recently, collaboration among the Asian NRDC members is being further developed under the support of the Asia-Africa Science Platform Program of the Japan Society for the Promotion of Science. We report the activity for three years to develop the Asian collaboration on nuclear reaction data compilation. (author)

Neuromorphic elements and systems as the basis for the physical implementation of artificial intelligence technologies

Science.gov (United States)

Demin, V. A.; Emelyanov, A. V.; Lapkin, D. A.; Erokhin, V. V.; Kashkarov, P. K.; Kovalchuk, M. V.

2016-11-01

The instrumental realization of neuromorphic systems may form the basis of a radically new social and economic setup, redistributing roles between humans and complex technical aggregates. The basic elements of any neuromorphic system are neurons and synapses. New memristive elements based on both organic (polymer) and inorganic materials have been formed, and the possibilities of instrumental implementation of very simple neuromorphic systems with different architectures on the basis of these elements have been demonstrated.

Calculation of the energetics of chemical reactions

Energy Technology Data Exchange (ETDEWEB)

Dunning, T.H. Jr.; Harding, L.B.; Shepard, R.L.; Harrison, R.J.

1988-01-01

To calculate the energetics of chemical reactions we must solve the electronic Schroedinger equation for the molecular conformations of importance for the reactive encounter. Substantial changes occur in the electronic structure of a molecular system as the reaction progresses from reactants through the transition state to products. To describe these changes, our approach includes the following three elements: the use of multiconfiguration self-consistent field wave functions to provide a consistent zero-order description of the electronic structure of the reactants, transition state, and products; the use of configuration interaction techniques to describe electron correlation effects needed to provide quantitative predictions of the reaction energetics; and the use of large, optimized basis sets to provide the flexibility needed to describe the variations in the electronic distributions. With this approach we are able to study reactions involving as many as 5--6 atoms with errors of just a few kcal/mol in the predicted reaction energetics. Predictions to chemical accuracy, i.e., to 1 kcal/mol or less, are not yet feasible, although continuing improvements in both the theoretical methodology and computer technology suggest that this will soon be possible, at least for reactions involving small polyatomic species. 4 figs.

Department of Nuclear Reactions: Overview

International Nuclear Information System (INIS)

Rusek, K.

2002-01-01

Full text: Department of Nuclear Reactions has had a very productive year. We have carried out our work in close collaborations with physicists from many laboratories, home and foreign. The following reports cover three major domains of our activities: nuclear, material and atomic physics. * Nuclear physics: In collaboration with scientists from Ukraine experimental studies of nuclear reaction induced by heavy ions from the Warsaw Cyclotron have been performed. The aim of the experiments is to study nuclear reactions leading to the exotic light nuclei in exit channels and energy dependence of the nucleus - nucleus interactions. Proton induced charge-exchange reactions were investigated theoretically by means of multistep-direct model. Good agreement with the experimental data was achieved. A novel approach to the problem of the nuclear liquid → gas phase transition was proposed, based on synergetics - a domain of science dealing with self-organization in macroscopic systems. Decay properties of the Roper resonance were studied. Final analysis of the analysing powers for the polarized deuterons scattered on protons was accomplished. Experimental programme of the near-threshold meson production in proton - proton scattering has been started in collaboration with Forschungszentrum. Juelich. * Atomic physics: Spectra of the X-rays emitted by energetic sulphur ions scattered off carbon atoms were analysed in order to study the role of the multiple charge states of the inner shells in the dynamics of the collision process. Ionization probabilities in collision of oxygen ions with gold atoms were measured. The observed disagreement of the experimental data with the theoretical predictions suggest a strong effect generated by the sub-shell couplings. * Materials research: Ion channelling method was applied to investigate transformation of the defects in Al x Ga 1-x As crystalline layers. Activities of our colleagues in didactics have grown considerably. Lectures

Mixing effects on apparent reaction rates and isotope fractionation during denitrification in a heterogeneous aquifer

Science.gov (United States)

Green, Christopher T.; Böhlke, John Karl; Bekins, Barbara A.; Phillips, Steven P.

2010-01-01

Gradients in contaminant concentrations and isotopic compositions commonly are used to derive reaction parameters for natural attenuation in aquifers. Differences between field‐scale (apparent) estimated reaction rates and isotopic fractionations and local‐scale (intrinsic) effects are poorly understood for complex natural systems. For a heterogeneous alluvial fan aquifer, numerical models and field observations were used to study the effects of physical heterogeneity on reaction parameter estimates. Field measurements included major ions, age tracers, stable isotopes, and dissolved gases. Parameters were estimated for the O2 reduction rate, denitrification rate, O2 threshold for denitrification, and stable N isotope fractionation during denitrification. For multiple geostatistical realizations of the aquifer, inverse modeling was used to establish reactive transport simulations that were consistent with field observations and served as a basis for numerical experiments to compare sample‐based estimates of “apparent” parameters with “true“ (intrinsic) values. For this aquifer, non‐Gaussian dispersion reduced the magnitudes of apparent reaction rates and isotope fractionations to a greater extent than Gaussian mixing alone. Apparent and true rate constants and fractionation parameters can differ by an order of magnitude or more, especially for samples subject to slow transport, long travel times, or rapid reactions. The effect of mixing on apparent N isotope fractionation potentially explains differences between previous laboratory and field estimates. Similarly, predicted effects on apparent O2threshold values for denitrification are consistent with previous reports of higher values in aquifers than in the laboratory. These results show that hydrogeological complexity substantially influences the interpretation and prediction of reactive transport.

Kinetics of reactions of chromium, molybdenum and tungsten hexacarbonyls with hydroxylamine and trimethylamine oxide

International Nuclear Information System (INIS)

Maksakov, V.A.; Ershova, V.A.

1994-01-01

Mechanism of M(CO) 6 (M = Cr, Mo, W) reaction with hydroxylamine was studied. On the basis of kinetic data it was ascertained that as a result of the reaction CO oxidation to CO 2 and intramolecular transfer of amine formed to the central atom of metal occur. Mechanisms of M(CO) 6 reactions with hydroxylamine and trimethylamine oxide are compared

Multiphoton control of the 1,3-cyclohexadiene ring-opening reaction in the presence of competing solvent reactions.

Science.gov (United States)

Carroll, Elizabeth C; White, James L; Florean, Andrei C; Bucksbaum, Philip H; Sension, Roseanne J

2008-07-31

Although physical chemistry has often concentrated on the observation and understanding of chemical systems, the defining characteristic of chemistry remains the direction and control of chemical reactivity. Optical control of molecular dynamics, and thus of chemical reactivity provides a path to use photon energy as a smart reagent in a chemical system. In this paper, we discuss recent research in this field in the context of our studies of the multiphoton optical control of the photo-initiated ring-opening reaction of 1,3-cyclohexadiene (CHD) to form 1,3,5- cis-hexatriene (Z-HT). Closed-loop feedback and learning algorithms are able to identify pulses that increase the desired target state by as much as a factor of two. Mechanisms for control are discussed through the influence of the intensity dependence, the nonlinear power spectrum, and the projection of the pulses onto low orders of polynomial phase. Control measurements in neat solvents demonstrate that competing solvent fragmentation reactions must also be considered. In particular, multiphoton excitation of cyclohexane alone is capable of producing hexatriene. Statistical analyses of data sets obtained in learning algorithm searches in neat cyclohexane and for CHD in hexane and cyclohexane highlight the importance of linear and quadratic chirp, while demonstrating that the control features are not so easily defined. Higher order phase components are also important. On the basis of these results the involvement of low-frequency ground-state vibrational modes is proposed. When the population is transferred to the excited state, momentum along the torsional coordinate may keep the wave packet localized as it moves toward the conical intersections controlling the yield of Z-HT.

SkyNet: A Modular Nuclear Reaction Network Library

Science.gov (United States)

Lippuner, Jonas; Roberts, Luke F.

2017-12-01

Almost all of the elements heavier than hydrogen that are present in our solar system were produced by nuclear burning processes either in the early universe or at some point in the life cycle of stars. In all of these environments, there are dozens to thousands of nuclear species that interact with each other to produce successively heavier elements. In this paper, we present SkyNet, a new general-purpose nuclear reaction network that evolves the abundances of nuclear species under the influence of nuclear reactions. SkyNet can be used to compute the nucleosynthesis evolution in all astrophysical scenarios where nucleosynthesis occurs. SkyNet is free and open source, and aims to be easy to use and flexible. Any list of isotopes can be evolved, and SkyNet supports different types of nuclear reactions. SkyNet is modular so that new or existing physics, like nuclear reactions or equations of state, can easily be added or modified. Here, we present in detail the physics implemented in SkyNet with a focus on a self-consistent transition to and from nuclear statistical equilibrium to non-equilibrium nuclear burning, our implementation of electron screening, and coupling of the network to an equation of state. We also present comprehensive code tests and comparisons with existing nuclear reaction networks. We find that SkyNet agrees with published results and other codes to an accuracy of a few percent. Discrepancies, where they exist, can be traced to differences in the physics implementations.

Physics and technology of spallation neutron sources

International Nuclear Information System (INIS)

Bauer, G.S.

1998-08-01

Next to fission and fusion, spallation is an efficient process for releasing neutrons from nuclei. Unlike the other two reactions, it is an endothermal process and can, therefore, not be used per se in energy generation. In order to sustain a spallation reaction, an energetic beam of particles, most commonly protons, must be supplied onto a heavy target. Spallation can, however, play an important role as a source of neutrons whose flux can be easily controlled via the driving beam. Up to a few GeV of energy, the neutron production is roughly proportional to the beam power. Although sophisticated Monte Carlo codes exist to compute all aspects of a spallation facility, many features can be understood on the basis of simple physics arguments. Technically a spallation facility is very demanding, not only because a reliable and economic accelerator of high power is needed to drive the reaction, but also, and in particular, because high levels of radiation and heat are generated in the target which are difficult to cope with. Radiation effects in a spallation environment are different from those commonly encountered in a reactor and are probably even more temperature dependent than the latter because of the high gas production rate. A commonly favored solution is the use of molten heavy metal targets. While radiation damage is not a problem in this case, except for the container, a number of other issues are discussed. (author)

Correlates of Leisure Time Physical Inactivity in a Scandinavian Population: A Basis for Interventions.

Science.gov (United States)

Bonn, Stephanie E; Alfredsson, Lars; Saevarsdottir, Saedis; Schelin, Maria E C

2016-11-01

Effective interventions are needed to increase physical activity in the general population. To target interventions, we need knowledge of insufficiently active groups in society. This study aims to identify demographic and health-related correlates of leisure-time physical inactivity in a general Scandinavian population. Study participants comprised 5734 control subjects, age 18 to 70 years, from 2 ongoing Swedish case-control studies. Participants self-reported their leisure-time physical activity level. The odds of being physically inactive were calculated using logistic regression. A total of 42% of participants were classified as physically inactive during leisure time. A lower prevalence of inactivity was associated with middle age, higher education, having previous experience of sports participation, following a low glycemic index/Mediterranean diet and having a light physical workload. A high prevalence of inactivity was associated with greater age, high body mass index, smoking, never drinking alcohol, having children, having a weak social network or lower levels of emotional support, and a low vegetable intake. Several factors were associated with leisure-time physical inactivity. Directing interventions to target groups defined by specific factors associated with physical inactivity could be an efficient way to increase activity and improve health in the general population.

Sex Equity and Physical Activity Levels in Coeducational Physical Education: Exploring the Potential of Modified Game Forms

Science.gov (United States)

Van Acker, Ragnar; da Costa, Francisco Carreiro; De Bourdeaudhuij, Ilse; Cardon, Greet; Haerens, Leen

2010-01-01

Background: Physical education should promote an active and healthy lifestyle with an emphasis on students' preparation for lifelong physical activity. "Healthy People 2010" recommends that physical education is offered on a daily basis and that pupils engage in physical activities of moderate to vigorous intensity (MVPA) during at least…

Estimating the CCSD basis-set limit energy from small basis sets: basis-set extrapolations vs additivity schemes

Energy Technology Data Exchange (ETDEWEB)

Spackman, Peter R.; Karton, Amir, E-mail: amir.karton@uwa.edu.au [School of Chemistry and Biochemistry, The University of Western Australia, Perth, WA 6009 (Australia)

2015-05-15

Coupled cluster calculations with all single and double excitations (CCSD) converge exceedingly slowly with the size of the one-particle basis set. We assess the performance of a number of approaches for obtaining CCSD correlation energies close to the complete basis-set limit in conjunction with relatively small DZ and TZ basis sets. These include global and system-dependent extrapolations based on the A + B/L{sup α} two-point extrapolation formula, and the well-known additivity approach that uses an MP2-based basis-set-correction term. We show that the basis set convergence rate can change dramatically between different systems(e.g.it is slower for molecules with polar bonds and/or second-row elements). The system-dependent basis-set extrapolation scheme, in which unique basis-set extrapolation exponents for each system are obtained from lower-cost MP2 calculations, significantly accelerates the basis-set convergence relative to the global extrapolations. Nevertheless, we find that the simple MP2-based basis-set additivity scheme outperforms the extrapolation approaches. For example, the following root-mean-squared deviations are obtained for the 140 basis-set limit CCSD atomization energies in the W4-11 database: 9.1 (global extrapolation), 3.7 (system-dependent extrapolation), and 2.4 (additivity scheme) kJ mol{sup –1}. The CCSD energy in these approximations is obtained from basis sets of up to TZ quality and the latter two approaches require additional MP2 calculations with basis sets of up to QZ quality. We also assess the performance of the basis-set extrapolations and additivity schemes for a set of 20 basis-set limit CCSD atomization energies of larger molecules including amino acids, DNA/RNA bases, aromatic compounds, and platonic hydrocarbon cages. We obtain the following RMSDs for the above methods: 10.2 (global extrapolation), 5.7 (system-dependent extrapolation), and 2.9 (additivity scheme) kJ mol{sup –1}.

Estimating the CCSD basis-set limit energy from small basis sets: basis-set extrapolations vs additivity schemes

International Nuclear Information System (INIS)

Spackman, Peter R.; Karton, Amir

2015-01-01

Coupled cluster calculations with all single and double excitations (CCSD) converge exceedingly slowly with the size of the one-particle basis set. We assess the performance of a number of approaches for obtaining CCSD correlation energies close to the complete basis-set limit in conjunction with relatively small DZ and TZ basis sets. These include global and system-dependent extrapolations based on the A + B/L α two-point extrapolation formula, and the well-known additivity approach that uses an MP2-based basis-set-correction term. We show that the basis set convergence rate can change dramatically between different systems(e.g.it is slower for molecules with polar bonds and/or second-row elements). The system-dependent basis-set extrapolation scheme, in which unique basis-set extrapolation exponents for each system are obtained from lower-cost MP2 calculations, significantly accelerates the basis-set convergence relative to the global extrapolations. Nevertheless, we find that the simple MP2-based basis-set additivity scheme outperforms the extrapolation approaches. For example, the following root-mean-squared deviations are obtained for the 140 basis-set limit CCSD atomization energies in the W4-11 database: 9.1 (global extrapolation), 3.7 (system-dependent extrapolation), and 2.4 (additivity scheme) kJ mol –1 . The CCSD energy in these approximations is obtained from basis sets of up to TZ quality and the latter two approaches require additional MP2 calculations with basis sets of up to QZ quality. We also assess the performance of the basis-set extrapolations and additivity schemes for a set of 20 basis-set limit CCSD atomization energies of larger molecules including amino acids, DNA/RNA bases, aromatic compounds, and platonic hydrocarbon cages. We obtain the following RMSDs for the above methods: 10.2 (global extrapolation), 5.7 (system-dependent extrapolation), and 2.9 (additivity scheme) kJ mol –1

New methods in nuclear reaction theory

International Nuclear Information System (INIS)

Redish, E.F.

1979-01-01

Standard nuclear reaction methods are limited to treating problems that generalize two-body scattering. These are problems with only one continuous (vector) degree of freedom (CDOF). The difficulty in extending these methods to cases with two or more CDOFs is not just the additional numerical complexity: the mathematical problem is usually not well-posed. It is hard to guarantee that the proper boundary conditions (BCs) are satisfied. Since this is not generally known, the discussion is begun by considering the physics of this problem in the context of coupled-channel calculations. In practice, the difficulties are usually swept under the rug by the use of a highly developed phenomenology (or worse, by the failure to test a calculation for convergence). This approach limits the kind of reactions that can be handled to ones occurring on the surface of where a second CDOF can be treated perturbatively. In the past twenty years, the work of Faddeev, the quantum three-body problem has been solved. Many techniques (and codes) are now available for solving problems with two CDOFs. A method for using these techniques in the nuclear N-body problem is presented. A set of well-posed (connected kernal) equations for physical scattering operators is taken. Then it is shown how approximation schemes can be developed for a wide range of reaction mechanisms. The resulting general framework for a reaction theory can be applied to a number of nuclear problems. One result is a rigorous treatment of multistep transfer reactions with the possibility of systematically generating corrections. The application of the method to resonance reactions and knock-out is discussed. 12 figures

Nuclear reaction data and nuclear reactors

Energy Technology Data Exchange (ETDEWEB)

Paver, N [University of Trieste (Italy); Herman, M [International Atomic Energy Agency, Vienna (Austria); Gandini, A [ENEA, Rome (Italy)

2001-12-15

These two volumes contain the lecture notes of the workshop 'Nuclear Reaction Data and Nuclear Reactors: Physics, Design and Safety', which was held at the Abdus Salam ICTP in the Spring of 2000. The workshop consisted of five weeks of lecture courses followed by practical computer exercises on nuclear data treatment and design of nuclear power systems. The spectrum of topics is wide enough to timely cover the state-of-the-art and the perspectives of this broad field. The first two weeks were devoted to nuclear reaction models and nuclear data evaluation. Nuclear data processing for applications to reactor calculations was the subject of the third week. On the last two weeks reactor physics and on-going projects in nuclear power generation, waste disposal and safety were presented.

Decision making for position-dependent obstructive sleep apnea syndrome on the basis of patient information and physical examinations of the upper airway, acquired on an outpatient basis.

Science.gov (United States)

Endo, Minoru; Kondo, Takahito; Shimada, Rie; Tsukahara, Kiyoaki

2018-06-01

Patients with body mass index (BMI) position-dependent OSAS. Diagnosis of position-dependent/position-independent OSAS can be difficult in patients satisfying both 'BMI >25 kg/m 2 ' and 'any of tongue enlargement (TE), palatine tonsil hypertrophy (PTH) and obstruction by Muller's maneuver (OMM)'. Polysomnography is warranted in such patients. The objective was to retrospectively elucidate criteria for differentiating position-dependent OSAS on the basis of patient information and physical examinations of the upper airway obtainable in clinics. The 643 patients were categorized as positional patients (PPs) or non-positional patients (NPPs). The patient background factors examined were sex, age, BMI, and hypertension. TE, PTH, pharyngeal tonsil hypertrophy, and OMM were evaluated. Cross-validation was performed using even-numbered registrations as the training set group (Group A) and odd-numbered registrations as the test case group (Group B). In Group A, patients with BMI <25 kg/m 2 were clearly more frequent among PP than among NPP. In Group A with BMI ≥25 kg/m 2 , significant differences were found for TE, PTH and OMM. Significant differences were found between 0 and 1/2/3 for number of factors. Results generated from Group A were validated in Group B.

On the mechanism of photocatalytic reactions with eosin Y

Directory of Open Access Journals (Sweden)

Michal Majek

2014-04-01

Full Text Available A combined spectroscopic, synthetic, and apparative study has allowed a more detailed mechanistic rationalization of several recently reported eosin Y-catalyzed aromatic substitutions at arenediazonium salts. The operation of rapid acid–base equilibria, direct photolysis pathways, and radical chain reactions has been discussed on the basis of pH, solvent polarity, lamp type, absorption properties, and quantum yields. Determination of the latter proved to be an especially valuable tool for the distinction between radical chain and photocatalytic reactions.

The Cascade-Exciton Approach to Nuclear Reactions. (Foundation and Achievements)

International Nuclear Information System (INIS)

Mashnik, S.G.

1994-01-01

The relativistic kinetic equations describing nuclear reactions at intermediate energies are obtained on the dynamical basis. These equations are analyzed and realized in several versions of the Cascade Exciton Model (CEM). The CEM assumes that reactions occur in three stages: the intranuclear cascade, pre-equilibrium and the evaporative ones. A large variety of experimental data on hadron- and photonuclear reactions in the bombarding energy range up to several GeV are analyzed in this approach. The contributions of different pion and photon absorption mechanisms and the relative role of different particle and photon production mechanisms in these reactions are estimated. The CEM describes adequately nuclear reactions at intermediate energies and has one of the best predictive powers as compared to other available modern models. 55 refs., 10 figs., 1 tab

Accurate Conformational Energy Differences of Carbohydrates: A Complete Basis Set Extrapolation

Czech Academy of Sciences Publication Activity Database

Csonka, G. I.; Kaminský, Jakub

2011-01-01

Roč. 7, č. 4 (2011), s. 988-997 ISSN 1549-9618 Institutional research plan: CEZ:AV0Z40550506 Keywords : MP2 * basis set extrapolation * saccharides Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 5.215, year: 2011

Physics The First Science

CERN Document Server

LINDENFELD, Peter

2011-01-01

Today's physics textbooks have become encyclopedic, offering students dry discussions, rote formulas, and exercises with little relation to the real world. Physics: The First Science offers uniquely accessible, student-friendly explanations, historical and philosophical perspectives and mathematics in easy-to-comprehend dialogue. It emphasizes the unity of physics and its place as the basis for all science. With their experience instructing both students and teachers of physics for decades, Peter Lindenfeld and Suzanne White Brahmia have developed an algebra-based physics book with fea

Reaction mechanism and spectroscopy of transfer reactions induced by heavy ions

International Nuclear Information System (INIS)

Lemaire, M.-C.

1977-01-01

The specific features displayed by data on heavy ion elastic and inelastic angular distributions are discussed, and their physical origin is pointed out from semi-classical calculations in counterpart ambiguities in the phenomenological description of the optical potential appear. Two nucleon transfer reactions induced by heavy ions successfully point out important contributions of a two-step process where the transfer is proceeding via target and residual nucleus inelastic excitation. At incident energies not too high above the Coulomb barrier, such process produces clear shape changes between different final state angular distributions. At higher incident energy, the angular distributions are forward peaked and display oscillations for both mechanisms. As for four-nucleon transfer reactions, the existing data suggest that the nucleons are well transferred into a Os relative

Effect of compound nuclear reaction mechanism in 12C(6Li,d) reaction at sub-Coulomb energy

Science.gov (United States)

Mondal, Ashok; Adhikari, S.; Basu, C.

2017-09-01

The angular distribution of the 12C(6Li,d) reaction populating the 6.92 and 7.12 MeV states of 16O at sub-Coulomb energy (Ecm=3 MeV) are analysed in the framework of the Distorted Wave Born Approximation (DWBA). Recent results on excitation function measurements and backward angle angular distributions derive ANC for both the states on the basis of an alpha transfer mechanism. In the present work, we show that considering both forward and backward angle data in the analysis, the 7.12 MeV state at sub-Coulomb energy is populated from Compound nuclear process rather than transfer process. The 6.92 MeV state is however produced from direct reaction mechanism.

Matrix isolation as a tool for studying interstellar chemical reactions

Science.gov (United States)

Ball, David W.; Ortman, Bryan J.; Hauge, Robert H.; Margrave, John L.

1989-01-01

Since the identification of the OH radical as an interstellar species, over 50 molecular species were identified as interstellar denizens. While identification of new species appears straightforward, an explanation for their mechanisms of formation is not. Most astronomers concede that large bodies like interstellar dust grains are necessary for adsorption of molecules and their energies of reactions, but many of the mechanistic steps are unknown and speculative. It is proposed that data from matrix isolation experiments involving the reactions of refractory materials (especially C, Si, and Fe atoms and clusters) with small molecules (mainly H2, H2O, CO, CO2) are particularly applicable to explaining mechanistic details of likely interstellar chemical reactions. In many cases, matrix isolation techniques are the sole method of studying such reactions; also in many cases, complexations and bond rearrangements yield molecules never before observed. The study of these reactions thus provides a logical basis for the mechanisms of interstellar reactions. A list of reactions is presented that would simulate interstellar chemical reactions. These reactions were studied using FTIR-matrix isolation techniques.

Nanocrystalline spinel ferrites by solid state reaction route

Indian Academy of Sciences (India)

Wintec

Nanocrystalline spinel ferrites by solid state reaction route. T K KUNDU* and S MISHRA. Department of Physics, Visva-Bharati, Santiniketan 731 235, India. Abstract. Nanostructured NiFe2O4, MnFe2O4 and (NiZn)Fe2O4 were synthesized by aliovalent ion doping using conventional solid-state reaction route. With the ...

Relationship between physical performance and self-reported function in healthy individuals across the lifespan.

Science.gov (United States)

Baldwin, Jennifer N; McKay, Marnee J; Hiller, Claire E; Moloney, Niamh; Nightingale, Elizabeth J; Burns, Joshua

2017-08-01

Functional outcome measures in clinical trials of musculoskeletal conditions need to be meaningful to individuals. To investigate the relationship between physical performance and self/proxy-reported function in 1000 healthy children and adults. Cross-sectional observational study (1000 Norms Project). One thousand males and females aged 3-101 years, healthy by self-report and without major physical disability, were recruited. Twelve performance-based tests were analysed: vertical and long jump, two hand dexterity tests, four balance tests, stepping reaction time, 30-second chair stand, timed up-and-down stairs, and six-minute walk. Self/proxy-reported function was assessed using the Infant-Toddler Quality of Life questionnaire, Child Health Questionnaire, Assessment of Quality of Life (AQoL)-6D Adolescent, AQoL-8D, International Physical Activity Questionnaire and work ability question. Bivariate and multivariate correlational analyses were constructed for infants (3-4y), children (5-10y), adolescents (11-17y), adults (18-59y) and older adults (60+). Socio-demographic characteristics were similar to the Australian population. Among infants/children, greater jump and sit-to-stand performance correlated with higher proxy-reported function (p  0.05). Greater jump, dexterity, balance, reaction time, sit-to-stand, stair-climbing and six-minute walk performance correlated with higher self-reported function in adults (r = -0.097 to.231; p physical measures which could form the basis of age-appropriate functional scales for clinical trials of musculoskeletal conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

REFORMASI SISTEM AKUNTANSI CASH BASIS MENUJU SISTEM AKUNTANSI ACCRUAL BASIS

Directory of Open Access Journals (Sweden)

Yuri Rahayu

2016-03-01

Full Text Available Abstract –  Accounting reform movement was born with the aim of structuring the direction of improvement . This movement is characterized by the enactment of the Act of 2003 and Act 1 of 2004, which became the basis of the birth of Government Regulation No.24 of 2005 on Government Accounting Standards ( SAP . The general,  accounting is based on two systems,  the cash basis  and the accrual basis. The facts speak far students still at problem with differences to the two methods that result in a lack of understanding on the treatment system for recording. The purpose method of research is particularly relevant to student references who are learning basic accounting so that it can provide information and more meaningful understanding of the accounting method cash basis and Accrual basis. This research was conducted through a normative approach, by tracing the document that references a study/library that combines source of reference that can be believed either from books and the internet are processed with a foundation of knowledge and experience of the author. The conclusion can be drawn that basically to be able to understand the difference of the system and the Cash Basis accrual student base treatment requires an understanding of both methods. To be able to have the ability and understanding of both systems required reading exercises and reference sources.   Keywords : Reform, cash basis, accrual basis   Abstrak - Gerakan reformasi akuntansi dilahirkan dengan tujuan penataan ke arah perbaikan. Gerakan ini  ditandai dengan dikeluarkannya  Undang-Undang tahun 2003 dan Undang-Undang No.1 Tahun 2004  yang menjadi dasar lahirnya Peraturan Pemerintah No.24 Tahun 2005 tentang Standar Akuntansi Pemerintah (SAP . Pada umumnya pencatatan akuntansi di dasarkan pada dua sistem yaitu basis kas (Cash Basis dan basis akrual  (Accrual Basis. Fakta berbicara Selama ini mahasiswa masih dibinggungkan dengan perbedaan ke dua metode itu sehingga

Precompound decay models for medium energy nuclear reactions

International Nuclear Information System (INIS)

Blann, M.

1989-11-01

The formulations used for precompound decay models are presented and explained in terms of the physics of the intranuclear cascade model. Several features of spectra of medium energy (10--1000 MeV) reactions are summarized. Results of precompound plus evaporation calculations from the code ALICE are compared with a wide body of proton, alpha, and heavy ion induced reaction data to illustrate both the power and deficiencies of predicting yield of these reactions in the medium energy regime. 23 refs., 13 figs

Theory of nuclear reactions, with applications to heavy ion scattering reactions

International Nuclear Information System (INIS)

Youssef, M.S.A.

1981-01-01

Nuclear science to day, has gained its stature through the pioneer work of both theorists and experimentalists within its two main divisions, Nuclear Reaction and Nuclear Structure theories. Our main interest in this theoretical work in nuclear reaction theory is focused on three topics, come under the headings of three parts which are the constituents of the present paper. Part 1 is concerned with ''Contributions to the theory of Threshold phenomena in nuclear reactions; cluster threshold states in heavy ion reactions''. Part II is devoted to ''Hermiticity of the Laplacian operator, R-matrix theories and direct interaction theory'', while part xII is ascribed to ''Heavy ion transfer reactions and scattering''. The aforementioned selected topics are the backbones of this thesis, which starts with general introduction giving a brief account about the material included in. In each part, investiqations are given in an extended manner through several chapters. Finally, the thesis is ended eith the chapter on ''General Discussions and Conclusions''. Appendices, references, and figure captions are found at the end of each part, the matter which we believe to facilitate much the reading through of the thesis. The first two parts are based (to some extent) on the same formal background (R-matrix, Kapur-Peierls-theories) and they converge to solve some physical problems originating from flux conservation laws in nuclear reactions, while the third part is indirect related to the first two; in principle it joins the other two parts under computational aspects. All of them after all, form the solidarity of the material included in the thesis. (author)

Nuclear Physics Division biennial report 1993-1994

International Nuclear Information System (INIS)

Kumar, K.; Kataria, S.K.

1995-01-01

The activities of the Nuclear Physics Division of Bhabha Atomic Research Centre for the two year period January 1993 to December 1994 are summarised. The experimental nuclear physics research activities are centred around the 14 UD Pelletron accelerator. Instrumentation development for the research utilization of the accelerator as well as accelerator development activities connected with the superconducting LINAC booster are included. During the period the conversion of the 5.5 MV single stage Van de Graaff Accelerator into a 7 MV folded tandem accelerator for light and heavy ions, for use not only in low energy nuclear physics but also in various inter-disciplinary areas was carried out. The research activity in the field of study of heavy ion reactions involving elastic scattering, transfer reactions, fusion-fission phenomena, heavy ion resonances, high energy photons in nuclear reactions and level density determination from charged particle spectra emitted in heavy ion reactions are given. (author). refs., figs., tabs

Nuclear medical physics

International Nuclear Information System (INIS)

Williams, L.E.

1987-01-01

This three-volume set covers the physical basis of nuclear medicine, and is intended as a source of data for practicing scientists and physicians as well as those beginning their careers or simply studying nuclear medical physics. It leads the reader from quantum theory to the production and attenuation of ionizing radiation; considers dosimetry and the most recent assessment of biological effects of such particles; describes in detail detector materials, signal analysis, and gamma cameras; includes extensive discussions of bone mineral measurement as well as magnetic resonance imaging; covers limited angle, rotating camera, and positron tomography; presents quality assurance and statistical theory with an eye toward enhanced departmental operations; and features descriptions of functional imaging and the psychophysical basis of diagnosis

Accurate Determination of the Values of Fundamental Physical Constants: The Basis of the New "Quantum" SI Units

Science.gov (United States)

Karshenboim, S. G.

2018-03-01

The metric system appeared as the system of units designed for macroscopic (laboratory scale) measurements. The progress in accurate determination of the values of quantum constants (such as the Planck constant) in SI units shows that the capabilities in high-precision measurement of microscopic and macroscopic quantities in terms of the same units have increased substantially recently. At the same time, relative microscopic measurements (for example, the comparison of atomic transition frequencies or atomic masses) are often much more accurate than relative measurements of macroscopic quantities. This is the basis for the strategy to define units in microscopic phenomena and then use them on the laboratory scale, which plays a crucial role in practical methodological applications determined by everyday life and technologies. The international CODATA task group on fundamental constants regularly performs an overall analysis of the precision world data (the so-called Adjustment of the Fundamental Constants) and publishes their recommended values. The most recent evaluation was based on the data published by the end of 2014; here, we review the corresponding data and results. The accuracy in determination of the Boltzmann constant has increased, the consistency of the data on determination of the Planck constant has improved; it is these two dimensional constants that will be used in near future as the basis for the new definition of the kelvin and kilogram, respectively. The contradictions in determination of the Rydberg constant and the proton charge radius remain. The accuracy of determination of the fine structure constant and relative atomic weight of the electron has improved. Overall, we give a detailed review of the state of the art in precision determination of the values of fundamental constants. The mathematical procedure of the Adjustment, the new data and results are considered in detail. The limitations due to macroscopic properties of material

A reaction-based paradigm to model reactive chemical transport in groundwater with general kinetic and equilibrium reactions

International Nuclear Information System (INIS)

Zhang, Fan; Yeh, Gour-Tsyh; Parker, Jack C.; Brooks, Scott C; Pace, Molly; Kim, Young Jin; Jardine, Philip M.; Watson, David B.

2007-01-01

This paper presents a reaction-based water quality transport model in subsurface flow systems. Transport of chemical species with a variety of chemical and physical processes is mathematically described by M. partial differential equations (PDEs). Decomposition via Gauss-Jordan column reduction of the reaction network transforms M. species reactive transport equations into two sets of equations: a set of thermodynamic equilibrium equations representing NE equilibrium reactions and a set of reactive transport equations of M-NE kinetic-variables involving no equilibrium reactions (a kinetic-variable is a linear combination of species). The elimination of equilibrium reactions from reactive transport equations allows robust and efficient numerical integration. The model solves the PDEs of kinetic-variables rather than individual chemical species, which reduces the number of reactive transport equations and simplifies the reaction terms in the equations. A variety of numerical methods are investigated for solving the coupled transport and reaction equations. Simulation comparisons with exact solutions were performed to verify numerical accuracy and assess the effectiveness of various numerical strategies to deal with different application circumstances. Two validation examples involving simulations of uranium transport in soil columns are presented to evaluate the ability of the model to simulate reactive transport with complex reaction networks involving both kinetic and equilibrium reactions

A reaction-based paradigm to model reactive chemical transport in groundwater with general kinetic and equilibrium reactions.

Science.gov (United States)

Zhang, Fan; Yeh, Gour-Tsyh; Parker, Jack C; Brooks, Scott C; Pace, Molly N; Kim, Young-Jin; Jardine, Philip M; Watson, David B

2007-06-16

This paper presents a reaction-based water quality transport model in subsurface flow systems. Transport of chemical species with a variety of chemical and physical processes is mathematically described by M partial differential equations (PDEs). Decomposition via Gauss-Jordan column reduction of the reaction network transforms M species reactive transport equations into two sets of equations: a set of thermodynamic equilibrium equations representing N(E) equilibrium reactions and a set of reactive transport equations of M-N(E) kinetic-variables involving no equilibrium reactions (a kinetic-variable is a linear combination of species). The elimination of equilibrium reactions from reactive transport equations allows robust and efficient numerical integration. The model solves the PDEs of kinetic-variables rather than individual chemical species, which reduces the number of reactive transport equations and simplifies the reaction terms in the equations. A variety of numerical methods are investigated for solving the coupled transport and reaction equations. Simulation comparisons with exact solutions were performed to verify numerical accuracy and assess the effectiveness of various numerical strategies to deal with different application circumstances. Two validation examples involving simulations of uranium transport in soil columns are presented to evaluate the ability of the model to simulate reactive transport with complex reaction networks involving both kinetic and equilibrium reactions.

Inverse-Electron-Demand Diels-Alder Reactions: Principles and Applications.

Science.gov (United States)

Png, Zhuang Mao; Zeng, Huining; Ye, Qun; Xu, Jianwei

2017-09-05

Inverse-electron-demand Diels-Alder (iEDDA) reactions are an intriguing class of cycloaddition reactions that have attracted increasing attention for their application in bioorthogonal chemistry, the total synthesis of natural products, and materials science. In many cases, the application of the iEDDA reaction has been demonstrated as an innovative approach to achieve target structures. The theoretical aspects of this class of reactions are of particular interest for scientists as a means to understand the various factors, such as steric strain and electron density of the attached groups, that govern the reaction and thus to elucidate the reaction mechanism. This review aims to summarize both theoretical investigations and application-driven research work on the iEDDA reaction. First, the historical aspects and the theoretical basis of the reaction, especially recent advances in time-dependent density functional theory (TD-DFT) calculations, as well as catalysis strategies will be highlighted and discussed. Second, the applications of this novel reaction in the context of materials science, bioorthogonal chemistry, and total synthesis of natural products will be elaborated with selected recent examples. The challenges and opportunities of the iEDDA reaction will be highlighted to give more insight into its potential applications in many other research areas. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Physics in Africa

Energy Technology Data Exchange (ETDEWEB)

Allotey, F K.A.

1996-09-01

The paper discusses the role of basic sciences in the development of technology. This is then tied up with the broader issue of the importance of scientific and technological knowledge in the socio-economic development of a country. Physics forms the basis for most of the natural and applied sciences and technology. The state of physics in Africa is reviewed. The need for regional and international cooperation in physics education and research in Africa is stressed. (author). 13 refs, 2 tabs.

Physics in Africa

International Nuclear Information System (INIS)

Allotey, F.K.A.

1996-09-01

The paper discusses the role of basic sciences in the development of technology. This is then tied up with the broader issue of the importance of scientific and technological knowledge in the socio-economic development of a country. Physics forms the basis for most of the natural and applied sciences and technology. The state of physics in Africa is reviewed. The need for regional and international cooperation in physics education and research in Africa is stressed. (author). 13 refs, 2 tabs

Problems of improving physical training at this stage of the transformation of the system of physical education

Directory of Open Access Journals (Sweden)

Oleksandr Aghyppo

2016-02-01

Full Text Available Purpose: building a system of recreational physical culture on the basis of taking into account the individual characteristics of physical development and physical condition of the local population. Material & Methods: analytical review of the scientific literature on the issue of the research; use the results of previous studies carried out in KSAFC in this area and published in «Slobozhanskyi science and sport bulletin» during 2015 year; the use methods of similarity and analogy, also signs semantic spaces. Results: insolubility of the problem individual approach in organizing recreational physical culture in the previous period explained lack of representation of the content of individual of norm in the assessment of physical development and methods of comparison measure the differences being compared multicomponent objects. In held scientific research were developed signs semantic spaces with the introducted in its a single measure of comparable signs it possible to establish the qualitative structure of objects to be compared with any number of comparable parameters. Obtained methods separation of equifinality results into its component quality components. It is possible to obtain methods of estimating the biological age with the establishment of the individual characteristics of its course; divide the physical condition of its component parts; obtain methods for determining the available physical preparedness depending on the characteristics of the flow of biological age and current physical condition. Conclusions: Obtained results of the research make it possible to proceed to the development of monitoring physical development, physical preparedness and physical condition of the various population groups and on this basis to create a scientifically based of system improving physical training on the basis of which to develop a complex of "ready to work and defense of the fatherland".

Investigation of Na-CO{sub 2} Reaction with Initial Reaction in Various Reacting Surface

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyun Su; Park, Gunyeop; Kim, Soo Jae; Park, Hyun Sun; Kim, Moo Hwan [POSTECH, Pohang (Korea, Republic of); Wi, Myung-Hwan [KAERI, Daejeon (Korea, Republic of)

2015-10-15

The reaction products that cause oxidation and erosion are threaten the heat transfer tubes so that it is necessary to investigate Na-CO{sub 2} reaction according to various experimental parameter. Unlike SWR, Na-CO{sub 2} reaction is more complex to deal with reaction kinetics. Since a comprehensive understanding of Na-CO{sub 2} reaction mechanism is crucial for the safety analysis, the reaction phenomenon under the various conditions was investigated. The current issue is to make a database for developing computational code for CO{sub 2} gas leak situation because it is experimentally difficult to analyze the actual accident situation. Most studies on Na-CO{sub 2} interaction reports that chemical reaction is getting vigorous as temperature increased and reactivity is sensitive as temperature change between 400 .deg. C and 600 .deg. C. Therefore, temperature range is determined based on the operating condition (450 - 500 .deg. C) of KALIMER-600 employed as supercritical CO{sub 2} brayton cycle energy conversion system for Na-CO{sub 2} heat exchanger. And next parameter is sodium surface area which contact between sodium and CO{sub 2} when CO{sub 2} is injected into sodium pool in the accident situation. So, the fundamental surface reaction is experimentally studied in the range of 8 - 12cm{sup 2}. Additionally, it has been reported in recent years that CO{sub 2} Flow rate affects reactivity less significantly and CO{sub 2} flow rate is assumed that 5 SLPM (standard liter per minute) is suitable as a basis for a small leakage. The finally selected control parameters is sodium temperature and reacting surface area with constant CO{sub 2} flow rate. Na-CO{sub 2} reaction test is performed for investigating risk of potential accident which contacts with liquid sodium and CO{sub 2}. Amount of reaction is saturated as time passed because of kept a balance between production of solid phase reaction products and amount of diffusivity. These results contribute to make a

Reactivity and selectivity of arenes in reactions with ozone

International Nuclear Information System (INIS)

Vysotskii, Yu.B.; Mestechkin, M.M.; Sivyakova, L.N.; Tyupalo, N.F.

1987-01-01

The reactions of arenes with ozone, distinguished by the variety of products (quinones, aldehydes, acids), are of interest not only from the theoretical standpoint but also are of preparative value in the case of polycyclic hydrocarbons. In this work a quantitative treatment of this reaction is given on the basis of direct kinetic measurements and simple quantum chemical means, permitting its rate constants and the yield of the products to be related to the elements of electronic structure readily subject to quantum mechanical calculation

Advanced Test Reactor Safety Basis Upgrade Lessons Learned Relative to Design Basis Verification and Safety Basis Management

International Nuclear Information System (INIS)

G. L. Sharp; R. T. McCracken

2004-01-01

The Advanced Test Reactor (ATR) is a pressurized light-water reactor with a design thermal power of 250 MW. The principal function of the ATR is to provide a high neutron flux for testing reactor fuels and other materials. The reactor also provides other irradiation services such as radioisotope production. The ATR and its support facilities are located at the Test Reactor Area of the Idaho National Engineering and Environmental Laboratory (INEEL). An audit conducted by the Department of Energy's Office of Independent Oversight and Performance Assurance (DOE OA) raised concerns that design conditions at the ATR were not adequately analyzed in the safety analysis and that legacy design basis management practices had the potential to further impact safe operation of the facility.1 The concerns identified by the audit team, and issues raised during additional reviews performed by ATR safety analysts, were evaluated through the unreviewed safety question process resulting in shutdown of the ATR for more than three months while these concerns were resolved. Past management of the ATR safety basis, relative to facility design basis management and change control, led to concerns that discrepancies in the safety basis may have developed. Although not required by DOE orders or regulations, not performing design basis verification in conjunction with development of the 10 CFR 830 Subpart B upgraded safety basis allowed these potential weaknesses to be carried forward. Configuration management and a clear definition of the existing facility design basis have a direct relation to developing and maintaining a high quality safety basis which properly identifies and mitigates all hazards and postulated accident conditions. These relations and the impact of past safety basis management practices have been reviewed in order to identify lessons learned from the safety basis upgrade process and appropriate actions to resolve possible concerns with respect to the current ATR safety

Reaction cross section calculation of some alkaline earth elements

Science.gov (United States)

Tel, Eyyup; Kavun, Yusuf; Sarpün, Ismail Hakki

2017-09-01

Reaction cross section knowledge is crucial to application nuclear physics such as medical imaging, radiation shielding and material evaluations. Nuclear reaction codes can be used if the experimental data are unavailable or are improbably to be produced because of the experimental trouble. In this study, there action cross sections of some target alkaline earth elements have been calculated by using pre-equilibrium and equilibrium nuclear reaction models for nucleon induced reactions. While these calculations, the Hybrid Model, the Geometry Dependent Hybrid Model, the Full Exciton Model, the Cascade Exciton Model for pre-equilibrium reactions and the Weisskopf-Ewing Model for equilibrium reactions have been used. The calculated cross sections have been discussed and compared with the experimental data taken from Experimental Nuclear Reaction Data library.

Developing physics basis for the snowflake divertor in the DIII-D tokamak

Science.gov (United States)

Soukhanovskii, V. A.; Allen, S. L.; Fenstermacher, M. E.; Lasnier, C. J.; Makowski, M. A.; McLean, A. G.; Meyer, W. H.; Ryutov, D. D.; Kolemen, E.; Groebner, R. J.; Hyatt, A. W.; Leonard, A. W.; Osborne, T. H.; Petrie, T. W.; Watkins, J.

2018-03-01

divertor was found. The results complement the initial SF divertor studies conducted in high-power H-mode discharges in the NSTX and DIII-D tokamaks, and, along with snowflake divertor results from TCV and other tokamaks, contribute to the physics basis of the SF divertor as a power exhaust concept for future high power density tokamaks.

Associations of workplace bullying and harassment with stress reactions: a two-year follow-up study

Science.gov (United States)

TANIGUCHI, Toshiyo; TAKAKI, Jiro; HIROKAWA, Kumi; FUJII, Yasuhito; HARANO, Kaori

2015-01-01

The purpose of this prospective study was to investigate the effect of the patterning of workplace bullying and harassment over two time points (chronic, remission, onset, and never) on psychological and physical stress reactions. The subjects were 543 workers at welfare facilities for the elderly in Japan who completed a self-administered questionnaire at Time 1 (from August to September, 2009) and at Time 2 (from September to October, 2011). Workplace bullying and harassment were assessed using the Negative Acts Questionnaire (NAQ). Stress reactions were assessed using the Brief Job Stress Questionnaire. In the multiple logistic regression analyses, onset of person-related bullying was significantly (ppsychological and physical stress reactions at Time 2. Chronic form of person-related bullying was significantly (ppsychological stress reaction at Time 2. Onset of sexual harassment was significantly (psexual harassment was significantly (psexual harassment can cause stress reactions. Remission of sexual harassment can terminate physical stress reaction. PMID:26537998

Multilayer Network Analysis of Nuclear Reactions

Science.gov (United States)

Zhu, Liang; Ma, Yu-Gang; Chen, Qu; Han, Ding-Ding

2016-08-01

The nuclear reaction network is usually studied via precise calculation of differential equation sets, and much research interest has been focused on the characteristics of nuclides, such as half-life and size limit. In this paper, however, we adopt the methods from both multilayer and reaction networks, and obtain a distinctive view by mapping all the nuclear reactions in JINA REACLIB database into a directed network with 4 layers: neutron, proton, 4He and the remainder. The layer names correspond to reaction types decided by the currency particles consumed. This combined approach reveals that, in the remainder layer, the β-stability has high correlation with node degree difference and overlapping coefficient. Moreover, when reaction rates are considered as node strength, we find that, at lower temperatures, nuclide half-life scales reciprocally with its out-strength. The connection between physical properties and topological characteristics may help to explore the boundary of the nuclide chart.

Investigating Ionic Effects Applied to Water Based Organocatalysed Aldol Reactions

Directory of Open Access Journals (Sweden)

Joshua P. Delaney

2011-12-01

Full Text Available Saturated aqueous solutions of various common salts were examined for their effect on aqueous aldol reactions catalysted by a highly active C2-symmetric diprolinamide organocatalyst developed in our laboratory. With respect to the aldol reaction between cyclohexanone and 4-nitrobenzaldehyde, deionised water was always a superior medium to salt solutions though some correlation to increasing anion size and depression in enantiomeric excess could be observed. Additionally, the complete inhibition of catalyst activity observed when employing tap water could be alleviated by the inclusion of ethylenediaminetetraacetate (EDTA into the aqueous media prior to reaction initiation. Extension of these reaction conditions demonstrated that these ionic effects vary on a case-to-case basis depending on the ketone/aldehyde combination.

The HERA physics programme

International Nuclear Information System (INIS)

Saxon, D.H.

1991-09-01

The construction of the HERA accelerator and its detectors H1 and ZEUS opens up new physic regimes to explore at high-Q 2 and low-x. The physics interest and methods of exploration are described, starting from the environment provided by the accelerator and the reaction kinematics. (orig.)

The reactions of oxygen and hydrogen with liquid sodium

International Nuclear Information System (INIS)

Ullmann, H.

1981-01-01

Results so far available as to the reactions and chemical equilibrium of oxygen and hydrogen with liquid sodium have been analyzed critically. The enthalpy values of the reactions have been discussed and supplemented on the basis of corresponding BORN-HABER cycles. The concentration and temperature functions of the hydrogen equilibrium pressure were deduced from experimental results. In relation to the solubility data the solid phases coexisting with liquid sodium in the ternary system Na-O-H have been discussed. The reaction of oxygen with hydrogen in diluted solution in liquid sodium has been investigated in more detail. Interaction coefficients, and the temperature functions of the free energy of formation and the equilibrium constant have been determined. (orig.)

Design Basis Threat (DBT) Approach for the First NPP Security System in Indonesia

International Nuclear Information System (INIS)

Ign Djoko Irianto

2004-01-01

Design Basis Threat (DBT) is one of the main factors to be taken into account in the design of physical protection system of nuclear facility. In accordance with IAEA's recommendations outlined in INFCIRC/225/Rev.4 (Corrected), DBT is defined as: attributes and characteristics of potential insider and/or external adversaries, who might attempt unauthorized removal of nuclear material or sabotage against the nuclear facilities. There are three types of adversary that must be considered in DBT, such as adversary who comes from the outside (external adversary), adversary who comes from the inside (internal adversary), and adversary who comes from outside and colludes with insiders. Current situation in Indonesia, where many bomb attacks occurred, requires serious attention on DBT in the physical protection design of NPP which is to be built in Indonesia. This paper is intended to describe the methodology on how to create and implement a Design Basis Threat in the design process of NPP physical protection in Indonesia. (author)

Theses of reports 'V Conference of high energy physics, nuclear physics and accelerators'

International Nuclear Information System (INIS)

Dovbnya, A.N.

2007-01-01

Nucleus structure study in the reactions on the charged particles; application of the nuclear and physical methods in the adjacent science fields; study and development of accelerators and accumulators of charged particles; basic research in an effort to develop the nuclear and physical methods for the nuclear power needs, medicine and industry; computed engineering in the physical studies; basic research of interaction processes of ultrarelativistic particles with monocrystals and substance; physics of detectors are submitted in proceedings of V Conference on High Energy Physics

Application of laser diagnostics to sodium-water chemical reaction field

International Nuclear Information System (INIS)

Deguchi, Yoshihiro; Tamura, Kenta; Muranaka, Ryota; Kusano, Koji; Kikuchi, Shin; Kurihara, Akikazu

2013-01-01

In a sodium-cooled fast reactor (SFR), liquid sodium is used as a heat transfer fluid because of its excellent heat transport capability. On the other hand, it has strong chemical reactivity with water vapor. One of the design basis accidents of the SFR is the water leakage into the liquid sodium flow by a breach of heat transfer tubes in a steam generator. Therefore the study on sodium-water chemical reactions is of paramount importance for safety reasons. This study aims to clarify the sodium-water reaction mechanisms using laser diagnostics. The sodium-water counter-flow reactions were measured using laser diagnostics such as laser induced fluorescence, CARS, Raman scattering and photo-fragmentation. The measurement results show that the sodium-water reaction proceeds mainly by the reaction Na + H 2 O → NaOH + H and the main product is NaOH in this reaction. Its forward and backward reaction rates tend to balance with each other and the whole reaction rate reduces as temperature increases. (author)

Textbook of physical chemistry

International Nuclear Information System (INIS)

Wedler, G.

1982-01-01

The textbook presents an introduction to physical-chemical fundamentals and working methods, deals with the chemical thermodynamics, structure of matter, the statistical theory of matter, and transport phenomena. The kinetics are presented by means of experimental methods and the evaluation of kinetic measurements; furtheron formal kinetic of more complicated reactions, reaction mechanisms, the theory of kinetics, the kinetics of reactions in solution, of heterogeneous reactions of electrode processes, and the catalysis are described. A mathematical appendix (determinants, vectors, operators, series, integrals, differential equations, Schroedinger equation, wave functions) and the solutions of the numerical calculation examples complete this book. (HK) [de

Nonlinear variational models for reaction and diffusion systems

International Nuclear Information System (INIS)

Tanyi, G.E.

1983-08-01

There exists a natural metric w.r.t. which the density dependent diffusion operator is harmonic in the sense of Eells and Sampson. A physical corollary of this statement is the property that any two regular points on the orbit of a reaction or diffusion operator can be connected by a path along which the reaction rate is constant. (author)

A simple recipe for modeling reaction-rate in flows with turbulent-combustion

Science.gov (United States)

Girimaji, Sharath S.

1991-01-01

A computationally viable scheme to account for chemical reaction in turbulent flows is presented. The multivariate beta-pdf model for multiple scalar mixing forms the basis of this scheme. Using the model scalar joint pdf and a general form of the instantaneous reaction-rate, the unclosed chemical reaction terms are expressed as simple functions of scalar means and the turbulent scalar energy. The calculation procedure requires that the mean scalar equations and only one other transport equation - for the turbulent scalar energy - be solved.

Systematics of the (n, t) reaction cross sections at 14 MeV

International Nuclear Information System (INIS)

Yao Lishan

1992-01-01

The systematic behaviour of the (n, t) reaction cross sections have been studied for medium and heavy mass nuclei at 14 MeV. An analysis of the gross trend, the isotope and odd-even effects are given. Possible reaction mechanisms are also discussed. A set of the systematics parameters have been extracted on the basis of the analyzing and fitting of the available data. The (n, t) reaction cross sections of some nuclei have been predicted and a good agreement with the measured data has been obtained

Annual report on nuclear physics activities

International Nuclear Information System (INIS)

Borie, E.; Doll, P.; Rebel, H.

1982-11-01

This report surveys the activities in fundamental research from July 1, 1981 to June 30, 1982 at the three institutes of the KfK which are concerned with nuclear physics. The research program comprises laser spectroscopy, nuclear reactions with light ions, neutron physics, neutrino physics and physics at medium and higher energies. (orig.) [de

Periodic-orbit formula for quantum reactions through transition states

NARCIS (Netherlands)

Schubert, Roman; Waalkens, Holger; Goussev, Arseni; Wiggins, Stephen

2010-01-01

Transition state theory forms the basis of computing reaction rates in chemical and other systems. Recently, it has been shown how transition state theory can rigorously be realized in phase space by using an explicit algorithm. The quantization has been demonstrated to lead to an efficient

Duff reaction on phenols: Characterization of non steam volatile products

Digital Repository Service at National Institute of Oceanography (India)

Wahidullah, S.; DeSouza, L.; Bhattacharya, J.

New products having structures 1 and 2 have been characterized in the Duff reaction thymol arid carvacrol. These products have been identified as 2.6'-dithymylmethane 1 and 5.5' -dicarvacryl methane 2 respectively on the basis of spectral data...

Physics of positronium acceptor complex formation reactions

International Nuclear Information System (INIS)

Gangopadhyay, Debarshi; Ganguly, Bichitra Nandi; Mukherjee, Tapas; Dutta-Roy, Binayak

2002-01-01

Positronium (P s ) reaction rates (κ) with weak Acceptors (Ac) leading to the formation of Ps-Ac complexes show several interesting features: non-monotonic temperature dependence of κ(departing from the usual Arrhenius behaviour), considerable variability of κ with respect to different solvents, and anomalies in response to external pressure at ambient temperature. The object of this work is to explain all these phenomena using a remarkably simple bubble model (the widely used model for the pick-off component of ortho-positronium decay in liquids), which has been revisited several times in the context and as a result smooth diffuse boundary of the bubble was suggested that yields reasonable agreement of the experimental data. The contractile force on the bubble relies much on the surface tension of the liquid, through our calculation the notion of critical surface tension emerges and enables us to explain the experimental observations satisfactorily. (author)

Institute of physics

International Nuclear Information System (INIS)

Anon.

1975-01-01

A survey is given of the personnel and activities of the Institute of Physics. Research by staff of the Nuclear Physics Group includes mainly work on heavy ion reactions and investigations of rare earth nuclei. The Elementary Particle Group has studied antineutron and antiproton annihilations, neutral current pions minus and has used the CERN ISRs. The Cosmic Physics Group has used rockets, satellite data and balloons to study the electron and proton precipitation in the upper atmosphere and magnetosphere, and aurorae. (JIW)

REACLIB: A Reaction Rate Library for the Era of Collaborative Science

Science.gov (United States)

Meisel, Zachary

2008-10-01

Thermonuclear reaction rates and weak decay rates are of great importance to modern nuclear astrophysics. They are critical in the study of many topics such as Big Bang Nucleosynthesis, X-ray bursts, Supernovae, and S-process element formation, among others. The Joint Institute for Nuclear Astrophysics (JINA) has been created to increase connectivity amongst nuclear astrophysicists in our modern age of highly collaborative science. Within JINA there has been an effort to create a frequently updated and readily accessible database of thermonuclear reactions and weak decay rates. This database is the REACLIB library, which can be accessed at the web address: http://www.nscl.msu.edu/˜nero/db/. Here I will discuss the JINA REACLIB Project, including a new procedure to fit reaction rates as a function of temperature that takes full advantage of physicality. With these updated reaction rates, astrophysical modelers will no longer have to worry about the adverse effects of using obsolete reaction rate libraries lacking physical behavior.

Classical simulations of heavy-ion fusion reactions and weakly ...

Indian Academy of Sciences (India)

82, No. 5. — journal of. May 2014 physics pp. 879–891. Classical simulations of heavy-ion fusion reactions and weakly-bound projectile breakup reactions ... on the collision energy and the moment of inertia of the deformed nucleus. ... where each individual nucleus consists of a number of protons and neutrons, in some.

Spin polarization and magnetic effects in radical reactions

International Nuclear Information System (INIS)

Salikhov, K.M.; Molin, Yu.N.; Sagdeev, R.Z.; Buchachenko, A.L.

1984-01-01

Studies on the effects of chemically induced dynamic nuclear and electron polarizations (CIDNP and CIDEP), and magnetic effects in radical reactions, have given rise to a new rapidly-progressing field of chemical physics. It came into being about ten years ago and has been attracting the ever-growing attention of researchers in related areas. The present book is a fairly all-embracing review of the state of affairs in this field. The book presents the physical background (both theoretical and experimental) of CIDNP and CIDEP, of the effects of an external magnetic field and magnetic nuclear moment (magnetic isotope effects) on radical reactions in solutions. Great attention has been paid to the application of chemical spin polarization and magnetic effects to solving various problems of chemical kinetics, structural chemistry, molecular physics, magnetobiology, and radiospectroscopy. The book will be useful for physicists, chemists and biologists employing CIDNP, CIDEP and magnetic effects in their investigations, as well as for researchers in related fields of chemical physics. The book can be also recommended for postgraduates and senior undergraduate students. (Auth.)

Annual report on nuclear physics activities

International Nuclear Information System (INIS)

Heeringa, W.; Voss, F.

1988-02-01

This report surveys the activities in basic research from July 1, 1986 to June 30, 1987 at the Institute for Nuclear Physics (IK) of the Nuclear Research Center Karlsruhe. The research program of this institute comprises laser spectroscopy, nuclear reactions with light ions, neutron physics, neutrino physics and high energy physics, as well as detector technology. (orig.) [de

The formation reaction of calcium hexa-aluminate

International Nuclear Information System (INIS)

Tuganova, S.Kh.; Sirajiddinov, N.A.

1990-01-01

The formation reaction of CaAl 12 O 19 at interaction of calcium oxide and aluminium in solid form has been studied. Some physical-chemical characteristics of calcium hexa-aluminate are given. (author)

Assessing physical function and physical activity in patients with CKD.

Science.gov (United States)

Painter, Patricia; Marcus, Robin L

2013-05-01

Patients with CKD are characterized by low levels of physical functioning, which, along with low physical activity, predict poor outcomes in those treated with dialysis. The hallmark of clinical care in geriatric practice and geriatric research is the orientation to and assessment of physical function and functional limitations. Although there is increasing interest in physical function and physical activity in patients with CKD, the nephrology field has not focused on this aspect of care. This paper provides an in-depth review of the measurement of physical function and physical activity. It focuses on physiologic impairments and physical performance limitations (impaired mobility and functional limitations). The review is based on established frameworks of physical impairment and functional limitations that have guided research in physical function in the aging population. Definitions and measures for physiologic impairments, physical performance limitations, self-reported function, and physical activity are presented. On the basis of the information presented, recommendations for incorporating routine assessment of physical function and encouragement for physical activity in clinical care are provided.

Charged-particle thermonuclear reaction rates: IV. Comparison to previous work

International Nuclear Information System (INIS)

Iliadis, C.; Longland, R.; Champagne, A.E.; Coc, A.

2010-01-01

We compare our Monte Carlo reaction rates (see Paper II of this issue) to previous results that were obtained by using the classical method of computing thermonuclear reaction rates. For each reaction, the comparison is presented using two types of graphs: the first shows the change in reaction rate uncertainties, while the second displays our new results normalized to the previously recommended reaction rate. We find that the rates have changed significantly for almost all reactions considered here. The changes are caused by (i) our new Monte Carlo method of computing reaction rates (see Paper I of this issue), and (ii) newly available nuclear physics information (see Paper III of this issue).

Physical and technical basis of positron emission tomography (PET)

International Nuclear Information System (INIS)

Bauer, R.

1994-01-01

Positron emission tomography utilizes the annihilation of positrons, generating pairs of gamma quanta which are emitted in opposing directions. 'Electronic collimation' is performed by coincident detection of both quanta. Thus, there is no need for mechanical collimators and no limiting connection between sensitivity and spatial resolution. Transversal tomograms are reconstructed from the projection data by means of highly sophisticated data processing. The half life of the most positron emitters used in medical applications is short and of the order of some minutes. Therefore, many positron emitters have to be produced on-side by means of a cyclotron. PET is superior to SPECT with respect to physical and technical aspects, but the high costs of PET limit its wide-spread use up to now. (orig.) [de

Reaction cross section calculation of some alkaline earth elements

Directory of Open Access Journals (Sweden)

Tel Eyyup

2017-01-01

Full Text Available Reaction cross section knowledge is crucial to application nuclear physics such as medical imaging, radiation shielding and material evaluations. Nuclear reaction codes can be used if the experimental data are unavailable or are improbably to be produced because of the experimental trouble. In this study, there action cross sections of some target alkaline earth elements have been calculated by using pre-equilibrium and equilibrium nuclear reaction models for nucleon induced reactions. While these calculations, the Hybrid Model, the Geometry Dependent Hybrid Model, the Full Exciton Model, the Cascade Exciton Model for pre-equilibrium reactions and the Weisskopf-Ewing Model for equilibrium reactions have been used. The calculated cross sections have been discussed and compared with the experimental data taken from Experimental Nuclear Reaction Data library.

Radiation reaction force and unification of electromagnetic and gravitational fields

International Nuclear Information System (INIS)

Lo, C.Y.; Goldstein, G.R.; Napier, A.

1981-04-01

A unified theory of electromagnetic and gravitational fields should modify classical electrodynamics such that the radiation reaction force is accounted for. The analysis leads to a five-dimensional unified theory of five variables. The theory is supported by showing that, for the case of a charged particle moving in a constant magnetic field, the radiation reaction force is indeed included. Moreover, this example shows explicitly that physical changes are associated with the fifth variable. Thus, the notion of a physical five-dimensional space should be seriously taken into consideration

Immediate allergic and nonallergic reactions to Christmas and Easter cacti

DEFF Research Database (Denmark)

Andersen, F; Bindslev-Jensen, C; Stahl Skov, P

1999-01-01

BACKGROUND: Occupational exposure to Christmas cacti has been reported as a cause of type I allergy. Therefore, the prevalence of immediate-type mucosal and skin reactions related to cactus exposure was studied in 103 employees in a cactus nursery. METHODS: The study was based on a questionnaire ...... and mucosal symptoms. CONCLUSIONS: Christmas and Easter cacti seemed to be able to induce contact urticaria and rhinoconjunctivitis on both an immunologic and a nonimmunologic basis. Personal atopy was associated with positive reactions to cacti....

Model for transport and reaction of defects and carriers within displacement cascades in gallium arsenide

International Nuclear Information System (INIS)

Wampler, William R.; Myers, Samuel M.

2015-01-01

A model is presented for recombination of charge carriers at evolving displacement damage in gallium arsenide, which includes clustering of the defects in atomic displacement cascades produced by neutron or ion irradiation. The carrier recombination model is based on an atomistic description of capture and emission of carriers by the defects with time evolution resulting from the migration and reaction of the defects. The physics and equations on which the model is based are presented, along with the details of the numerical methods used for their solution. The model uses a continuum description of diffusion, field-drift and reaction of carriers, and defects within a representative spherically symmetric cluster of defects. The initial radial defect profiles within the cluster were determined through pair-correlation-function analysis of the spatial distribution of defects obtained from the binary-collision code MARLOWE, using recoil energies for fission neutrons. Properties of the defects are discussed and values for their parameters are given, many of which were obtained from density functional theory. The model provides a basis for predicting the transient response of III-V heterojunction bipolar transistors to displacement damage from energetic particle irradiation

Crystalline state photoreactions direct observation of reaction processes and metastable intermediates

CERN Document Server

Ohashi, Yuji

2014-01-01

Offering some 300 references, this book focuses on chemical reactions in the crystalline state. The reactions span many fields in inorganic and organic chemistry, making this a useful resource for inorganic, organic and physical chemists and graduate students.

The theoretical basis of formation mental health of students on physical education

Directory of Open Access Journals (Sweden)

N.N. Muhamediarov

2013-06-01

Full Text Available It is determined socio-cultural component of the definition “mental health”. The theoretical approaches to the interpretation of “health” and “mental health”: philosophical, pedagogical, psychological, medical. It is highlighted the social aspect of these definitions. It is substantiated the relationship of mental health with physical. It is analyzed the impact of mental health on the future professional success. The ways of forming the mental health of students in the physical education are identified. Proposed introduction of alternative health methods for efficient formation of mental health, the creation of a data bank on the activities of association recreational subjects: fitness centers, swimming pools, skating rinks, gyms.

Developments in ITER physics R and D

International Nuclear Information System (INIS)

Aymar, R.

1999-01-01

The monograph details how by restructuring the ITER Physics Experts Groups the physics basis for the design effort can be improved while aiming for options for cost reduction. Tables with the new expert group structure are given together with tables of urgent physics research areas and personnel listings of the physics expert groups

Heavy-ion induced multinucleon transfer reactions in the 2s--1d shell

International Nuclear Information System (INIS)

Olmer, C.

1975-01-01

In order to investigate whether new nuclear structure information can be obtained from studying the direct transfer of more than two nucleons using heavy-ion projectiles, we have investigated the 28 Si( 16 O, 12 C) 32 S and 12 C( 14 N,d) 24 Mg reactions as candidates for the direct transfer of four- and twelve-nucleons, respectively. The counter telescope-position sensitive detector kinematic coincidence method--both angular distributions (22 0 less than theta/sub L/ less than 95 0 , E/sub L/ = 55.54 MeV) and excitation functions (theta/sub L/ = 26 0 , 50 less than E/sub L/ less than 63 MeV) were obtained for strongly excited states below 10 MeV in excitation in the first reaction. For the 12 C + 14 N interaction, a measurement of the angular distributions (25 0 less than theta/sub L/ less than 140 0 , E/sub L/ = 20,25 MeV) for proton, deuteron and alpha-particle emission to many low-lying states sufficed for the present purposes. Comparison of Hauser-Feshbach statistical model calculations with these data indicated that the light-particle production from the 12 C + 14 N interaction as investigated here is predominantly compound nuclear in nature. The selectively strong population of a few states in 32 S by the 28 Si-( 16 O, 12 C) 32 S reaction is primarily direct. The structure of these states was deduced from available light-ion-induced transfer reaction studies and shell model calculations; the importance of shell model configurations is indicated, and an alpha-particle transfer model can not account for the observed selectivity. Calculations of the 28 Si( 16 O, 12 C) 32 S reaction with a microscopic multinucleon transfer code indicate selectivities consistent with the present results. Moreover, the calculations suggest the presence of other, unexpected selectivities, all of which may be understood on a physical basis, and some of which appear as an extension of a similar effect seen in two-nucleon transfer reactions

The (n,p) reaction as a probe of nuclear structure

International Nuclear Information System (INIS)

Jackson, K.P.; Celler, A.

1988-08-01

An account is given of some results of studies of the (n,p) reaction on nuclear targets at TRIUMF. The (n,p) reaction, inducing spin flip transitions in isospin space, appears to exhibit a unique sensitivity to certain aspects of nuclear structure. The TRIUMF facility is the first to exploit the (n,p) reaction as a detailed probe of nuclear structure at energies above 65 MeV. In the (n,p) reaction Fermi transitions are absent, but there is a dramatic impact on Gamow-Teller and other collective transactions. Some nuclear transition matrix elements can be estimated on the basis of (n,p) measurements. Experiments have been carried out at TRIUMF on Li 6 , Fe 5 4, and Zr 9 0 targets. The calibration of the (n,p) reaction as a probe of the Gamow-Teller strength B + GT has been achieved for three targets. (L.L.) (45 refs., 10 figs.)

Nuclear Physics Division, Institute of Experimental Physics, Warsaw University Annual Report 1996

Energy Technology Data Exchange (ETDEWEB)

Szeflinski, Z.; Popkiewicz, M. [eds.

1997-12-31

In the presented report the research activities of Nuclear Physics Division (NPD) of the Institute of Experimental Physics (Warsaw University) in year 1996 are described. The report is divided into three parts: Reaction mechanisms and nuclear structure; Experimental methods and instrumentation and the third part contains the list of personnel, seminars held at the Nuclear Physics Division and published papers. A summary of the (NPD) activities are briefly presented in ``Preface`` by NPD director prof. Ch. Droste.

Nuclear Physics Division, Institute of Experimental Physics, Warsaw University annual report 1997

Energy Technology Data Exchange (ETDEWEB)

Szeflinski, Z.; Kirejczyk, M.; Popkiewicz, M. [eds.

1998-08-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Institute of Experimental Physics (Warsaw University) in year 1997 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one contain the lists of personnel, seminars held at the Nuclear Physics Division and published papers. A summary of the (NPD) activities are briefly presented in ``Preface`` written by NDP director prof. K. Siwek-Wilczynska

Nuclear Physics Division, Institute of Experimental Physics, Warsaw University annual report 1997

International Nuclear Information System (INIS)

Szeflinski, Z.; Kirejczyk, M.; Popkiewicz, M.

1998-01-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Institute of Experimental Physics (Warsaw University) in year 1997 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one contain the lists of personnel, seminars held at the Nuclear Physics Division and published papers. A summary of the (NPD) activities are briefly presented in ''Preface'' written by NDP director prof. K. Siwek-Wilczynska

Nuclear Physics Division, Institute of Experimental Physics, Warsaw University Annual Report 1996

International Nuclear Information System (INIS)

Szeflinski, Z.; Popkiewicz, M.

1997-01-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Institute of Experimental Physics (Warsaw University) in year 1996 are described. The report is divided into three parts: Reaction mechanisms and nuclear structure; Experimental methods and instrumentation and the third part contains the list of personnel, seminars held at the Nuclear Physics Division and published papers. A summary of the (NPD) activities are briefly presented in ''Preface'' by NPD director prof. Ch. Droste

Nuclear physics and neutronics

International Nuclear Information System (INIS)

Paya, D.

1997-01-01

After a brief review of the beginnings of the nuclear reaction physics in France in the 40's and 50's, the experimentation neutronics and nuclear physics studies are related and their uses presented, which aims were to provide data for the study of the various reactor concepts and to study fundamental physics. Progressively, pure nuclear physics lost its links with neutronics, and its influence decreases more or less. Long life radioactive waste reprocessing is an important domain where it could regain its contribution

Symmetry, Wigner functions and particle reactions

International Nuclear Information System (INIS)

Chavlejshvili, M.P.

1994-01-01

We consider the great principle of physics - symmetry - and some ideas, connected with it, suggested by a great physicist Eugene Wigner. We will discuss the concept of symmetry and spin, study the problem of separation of kinematics and dynamics in particle reactions. Using Wigner rotation functions (reflecting symmetry properties) in helicity amplitude decomposition and crossing-symmetry between helicity amplitudes (which contains the same Wigner functions) we get convenient general formalism for description of reactions between particles with any masses and spins. We also consider some applications of the formalism. 17 refs., 1 tab

Scatterings and reactions by means of polarized neutron beam

International Nuclear Information System (INIS)

Koori, N.

1989-01-01

A high resolution polarized neutron beam should be prepared for nuclear physics, which will be planned with the new ring cyclotron at RCNP. Studies on scatterings and reactions by means of polarized neutron beams are reviewed briefly. Beam lines for polarized neutrons are summarized. An example of high resolution measurements of neutron induced reactions is described. (author)

Enhancement Mechanisms of Low Energy Nuclear Reactions

OpenAIRE

Gareev, F. A.; Zhidkova, I. E.

2005-01-01

The review of possible stimulation mechanisms of LENR (low energy nuclear reaction) is represented. We have concluded that transmutation of nuclei at low energies and excess heat are possible in the framework of the modern physical theory - the universal resonance synchronization principle [1] and based on its different enhancement mechanisms of reaction rates are responsible for these processes [2]. The excitation and ionization of atoms may play role as a trigger for LENR. Superlow energy o...

Development, use and maintenance of the design basis threat. Implementing guide

International Nuclear Information System (INIS)

2009-01-01

threat to those assets. As described in this publication, an understanding of the threat can lead to a detailed description of potential adversaries (the design basis threat), which, in turn, is the basis of an appropriately designed physical protection system. This direct link gives confidence that protection would be effective against an adversary attack. International experience in using a design basis threat to protect assets of high consequence is largely based on the protection of nuclear material and facilities. Furthermore, the nuclear security documents defining and recommending that physical protection be based upon the threat - The Physical Protection Objectives and Fundamental Principles (GOV/2001/41/ Attachment), the Recommendations on the Physical Protection of Nuclear Facilities and Nuclear Material (INFCIRC/225/Rev. 4 (corrected)), and the Convention on Physical Protection of Nuclear Facilities and Nuclear Material as Amended (INFCIRC/274) (adopted on 8 July 2005; (GOV/2005/57)) - do so exclusively for the protection of nuclear material and facilities. Given the historical background, and its continuing contemporary relevance, it has been necessary to draw on that nuclear protection experience in developing this publication. However, the general approach can also be applied to protecting other assets that require a high degree of confidence in the effectiveness of their protection, such as high-activity radioactive material. Specialists from France, Germany, Japan, the Russian Federation, Spain, the United Kingdom, and the United States of America assisted the IAEA in preparing this publication. A draft was presented to an open-ended technical meeting in December 2006, and subsequently circulated for comment to all Member States. This publication is consistent with The Physical Protection Objectives and Fundamental Principles; the Convention on Physical Protection of Nuclear Facilities and Nuclear Material as Amended; and the Recommendations on the

Coupled modelling (transport-reaction) of the fluid-clay interactions and their feed back on the physical properties of the bentonite engineered clay barrier system

International Nuclear Information System (INIS)

Marty, N.

2006-11-01

The originality of this work is to process feed back effects of mineralogical and chemical modifications of clays, in storage conditions, on their physical properties and therefore on their transport characteristics (porosity, molecular diffusion, permeability). These feed back effects are modelled using the KIRMAT code (Kinetic of Reaction and MAss Transfer) developed from the kinetic code KINDIS by adding the effect of water renewal in the mineral-solution reactive cells. KIRMAT resolves mass balance equations associated with mass transport together with the geochemical reactions in a 1D approach. After 100 000 years of simulated interaction at 100 C, with the fluid of the Callovo-Oxfordian geological level (COX) and with iron provided by the steel overpack corrosion, the montmorillonite of the clay barrier is only partially transformed (into illite, chlorite, saponite...). Only outer parts of the modelled profile seem to be significantly affected by smectite dissolution processes, mainly at the interface with the geological environment. The modifications of physical properties show a closure of the porosity at the boundaries of the barrier, by creating a decrease of mass transport by molecular diffusion, essentially at the interface with the iron. Permeability laws applied to this system show a decrease of the hydraulic conductivity correlated with the porosity evolution. Near the COX, the swelling pressure of the clays from the barrier decreases. In the major part of the modelled profile, the engineered clay barrier system seems to keep its initial physical properties (porosity, molecular diffusion, permeability, swelling pressure) and functionalities. (author)

The 1989 annual report: Nuclear Physics Institute

International Nuclear Information System (INIS)

1989-01-01

The 1988 annual report of the Nuclear Physics Institute (Orsay, France) is presented. The results concerning exotic nuclei and structure studies by means of nuclear reactions are summarized. Research works involving the inertial fusion and the actinides are discussed. Theoretical and experimental work on the following fields is also included: high excitation energy nuclear states, heavy ion collision, intermediate energy nuclear physics, transfer reactions, dibaryonic resonances, thermodiffusion, management of radioactive wastes [fr

Charged-particle thermonuclear reaction rates: II. Tables and graphs of reaction rates and probability density functions

International Nuclear Information System (INIS)

Iliadis, C.; Longland, R.; Champagne, A.E.; Coc, A.; Fitzgerald, R.

2010-01-01

Numerical values of charged-particle thermonuclear reaction rates for nuclei in the A=14 to 40 region are tabulated. The results are obtained using a method, based on Monte Carlo techniques, that has been described in the preceding paper of this issue (Paper I). We present a low rate, median rate and high rate which correspond to the 0.16, 0.50 and 0.84 quantiles, respectively, of the cumulative reaction rate distribution. The meaning of these quantities is in general different from the commonly reported, but statistically meaningless expressions, 'lower limit', 'nominal value' and 'upper limit' of the total reaction rate. In addition, we approximate the Monte Carlo probability density function of the total reaction rate by a lognormal distribution and tabulate the lognormal parameters μ and σ at each temperature. We also provide a quantitative measure (Anderson-Darling test statistic) for the reliability of the lognormal approximation. The user can implement the approximate lognormal reaction rate probability density functions directly in a stellar model code for studies of stellar energy generation and nucleosynthesis. For each reaction, the Monte Carlo reaction rate probability density functions, together with their lognormal approximations, are displayed graphically for selected temperatures in order to provide a visual impression. Our new reaction rates are appropriate for bare nuclei in the laboratory. The nuclear physics input used to derive our reaction rates is presented in the subsequent paper of this issue (Paper III). In the fourth paper of this issue (Paper IV) we compare our new reaction rates to previous results.

3. Theoretical Physics Division

International Nuclear Information System (INIS)

For the period September 1980 - Aug 1981, the studies in theoretical physics divisions have been compiled under the following headings: in nuclear physics, nuclear structure, nuclear reactions and intermediate energies; in particle physics, NN and NantiN interactions, dual topological unitarization, quark model and quantum chromodynamics, classical and quantum field theories, non linear integrable equations and topological preons and Grand unified theories. A list of publications, lectures and meetings is included [fr

Combustion physics

Science.gov (United States)

Jones, A. R.

1985-11-01

Over 90% of our energy comes from combustion. By the year 2000 the figure will still be 80%, even allowing for nuclear and alternative energy sources. There are many familiar examples of combustion use, both domestic and industrial. These range from the Bunsen burner to large flares, from small combustion chambers, such as those in car engines, to industrial furnaces for steel manufacture or the generation of megawatts of electricity. There are also fires and explosions. The bountiful energy release from combustion, however, brings its problems, prominent among which are diminishing fuel resources and pollution. Combustion science is directed towards finding ways of improving efficiency and reducing pollution. One may ask, since combustion is a chemical reaction, why physics is involved: the answer is in three parts. First, chemicals cannot react unless they come together. In most flames the fuel and air are initially separate. The chemical reaction in the gas phase is very fast compared with the rate of mixing. Thus, once the fuel and air are mixed the reaction can be considered to occur instantaneously and fluid mechanics limits the rate of burning. Secondly, thermodynamics and heat transfer determine the thermal properties of the combustion products. Heat transfer also plays a role by preheating the reactants and is essential to extracting useful work. Fluid mechanics is relevant if work is to be performed directly, as in a turbine. Finally, physical methods, including electric probes, acoustics, optics, spectroscopy and pyrometry, are used to examine flames. The article is concerned mainly with how physics is used to improve the efficiency of combustion.

Kinetic modeling of reactions in Foods

NARCIS (Netherlands)

Boekel, van M.A.J.S.

2008-01-01

The level of quality that food maintains as it travels down the production-to-consumption path is largely determined by the chemical, biochemical, physical, and microbiological changes that take place during its processing and storage. Kinetic Modeling of Reactions in Foods demonstrates how to

Theoretical physics

International Nuclear Information System (INIS)

Anon.

1980-01-01

The nuclear theory program deals with the properties of nuclei and with the reactions and interactions between nuclei and a variety of projectiles. The main areas of concentration are: heavy-ion direct reactions at nonrelativistic energies; nuclear shell theory and nuclear structure; nuclear matter and nuclear forces;intermediate-energy physics and pion-nucleus interactions; and high-energy collisions of heavy ions. Recent progress and plans for future work in these five main areas of concentration and a summary of other theoretical studies currently in progress or recently completed are presented

Pramana – Journal of Physics | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Pramana – Journal of Physics. S Kailas. Articles written in Pramana – Journal of Physics. Volume 57 Issue 1 July 2001 pp 75-84 Invited Papers : Nuclear reactions. Light charged particle emission in heavy-ion reactions – What have we learnt? S Kailas · More Details Abstract Fulltext PDF. Light charged ...

Analysis of Cutaneous Adverse Drug Reactions at a Tertiary Care ...

African Journals Online (AJOL)

Erah

drug reactions (ADRs) reported at Civil Hospital, Ahmedabad, India. Methods: A prospective ... cost of ADRs was calculated on the basis of hospital expenditure per patient and the amount spent by patients ... drug control mechanisms, patient education regarding self-medication and maintenance of prescription records.

Temperamental Traits Versus Individual Physical Fitness Components and a Physical Activity Level

Directory of Open Access Journals (Sweden)

Bernatowicz Dominik

2015-06-01

Full Text Available The main aim of the study was to examine whether relationships exist between particular temperamental traits within the concept of Regulative Theory of Temperament and components of physical fitness, that are most crucial for success in sport. The research involved 108 individuals including 63 men (age 21.1 ± 1.6 yrs and 45 women (age 20.7 ± 1.3 yrs. None of the respondents were professionally engaged in sport. Components of physical fitness included: aerobic capacity, strength, agility, static-dynamic balance and reaction time. The respondents also completed two questionnaires: the Formal Characteristics of Behaviour – Temperament Inventory and the International Physical Activity Questionnaire. The results indicate that the temperamental traits had average to poor correlations with the components of physical fitness, whereas more statistically significant correlations were observed in women. Negative correlations were obtained between emotional reactivity and agility, which was a result confirmed by previous research. All temperamental traits related with the energetic aspects of behaviour correlated with simple reaction time in women. Physical activity and aerobic capacity did not correlate with any of the studied traits. The results do not allow for any general conclusions to be drawn, but can serve as a reference point for future research on temperamental traits as delineated by Regulative Theory of Temperament and their relationship with the components of physical fitness.

η production in proton-nucleus reactions

International Nuclear Information System (INIS)

Cassing, W.; Batko, G.; Vetter, T.; Wolf, G.

1991-01-01

The production of η-mesons in proton-nucleus reactions is analysed with respect to primary nucleon-nucleon (NN→NN η ) and secondary pion-nucleon (πN→ηN) production processes on the basis of Hartree-Fock groundstate momentum distributions and free on-shell production processes. The folding model adopted compares well for meson production with more involved simulations based on VUU transport equations. Similar to K + production in proton-nucleus reactions the η-mesons are primarily produced by the πN→ηN channel. However, η-mesons are absorbed in nuclei via excitation of the N * (1535) resonance which leads to strong distortions of the primordial spectra. On the other hand, the experimental mass dependence of the differential cross sections might yield information about the in-medium properties of this resonance. (orig.)

Chemical Reaction Equilibrium in Nanoporous Materials: NO Dimerization Reaction in Carbon Slit Nanopores

Czech Academy of Sciences Publication Activity Database

Lísal, Martin; Brennan, J.K.; Smith, W.R.

2006-01-01

Roč. 124, č. 6 (2006), s. 64712.1-64712.14 ISSN 0021-9606 R&D Projects: GA ČR(CZ) GA203/05/0725; GA AV ČR(CZ) 1ET400720507; GA AV ČR(CZ) 1ET400720409 Institutional research plan: CEZ:AV0Z40720504 Keywords : nanopore * NO dimerization * reaction Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.166, year: 2006

Effects on nuclear fusion reaction on diffusion and thermal conduction in a magnetoplasma

International Nuclear Information System (INIS)

Sakai, Kazuo; Aono, Osamu.

1976-12-01

In spite of the well spread belief in the field of irreversible thermodynamics, vectorial phenomena couple thermodynamically with the scalar phenomena. Transport coefficients concerning the diffusion and the thermal conduction across a strong magnetic field are calculated in the presence of the deuteron-triton fusion reaction on the basis of the gas kinetic theory. When the reaction takes place, the diffusion increases and the thermal conduction decreases. Effects of the reaction exceed those of the Coulomb collision as the temperature is high enough. (auth.)

Relative mobility of 1-H atoms of carbohydrates in heterogeneous isotope exchange reactions

International Nuclear Information System (INIS)

Akulov, G.P.; Snetkova, E.V.; Kayumov, V.G.; Kaminskii, Yu.L.

1988-01-01

The method of competitive reactions was used to determine the relative mobilities of the 1-H atoms of carbohydrates in reactions of heterogeneous isotope exchange, using various reference standards, catalysts, and buffer systems. On the basis of the results obtained, the investigated carbohydrates are ranged in a series of decreasing mobility of the hydrogen atoms exchanged in heterogeneous isotope exchange reactions. It was demonstrated that the mobility of the 1-H atoms is related to the concentration of the acyclic forms of the carbohydrates

Is Information a Sufficient Basis for Cognition? Part 2: Physical Foundations

Directory of Open Access Journals (Sweden)

José María Díaz Nafría

2011-10-01

Full Text Available In this second part of our inquiry into the relation between information and cognition, we delve into the physical limits of the manifestation of an arbitrary object first with independence of any observer, then considering the nature of perception. The analysis of the manifestations of an object in a homogeneous environment by means of wave phenomena shows that the information carried by such manifestations offers a constitutive fuzziness and ambiguity of the observed object. On the one hand, the details that can be specified concerning the object are strictly limited by the wave length; on the other hand, the volumetric details of the object (i.e. its bowls are outlawed to the observer, not in virtue of the object opacity, but to the very dimension or complexity of the wave phenomenon in the space surrounding the object. The analysis of perception, considering this physical boundary and the specificity of the animal sensitivity, shows the combined role of other concurrent or previous percept and some a priori knowledge in the perception and awareness of reality.

AN INVESTIGATION ON THE EFFECT OF FUNCTIONALISED GRAPHENE COMPOSITED WITH NCNT AND FE-NCNT ON THE OXYGEN REDUCTION REACTION VIA PHYSICAL MIXING METHOD

Directory of Open Access Journals (Sweden)

CHONG W.Z.

2016-02-01

Full Text Available Oxygen reduction reaction plays a major role in fuel cell applications to generate electricity by an electrochemical reaction. In this study, functionalised graphene composited with Fe-NCNT or NCNT were investigated on its ORR activity using a physical mixing method. Initially, functionalised graphene was produced via oxidation of graphene. NCNT and Fe-NCNT was obtained from the previously prepared samples using chemical vapour deposition technique and electrochemical reduction method for Fe-NCNT. The physical mixing between functionalised graphene and NCNT or Fe-NCNT was performed using sonication with the presence of pyrrole to produce the desired nanocatalyst. The surface morphologies and microstructures of the synthesised nanocatalysts were studied using field emission scanning electron microscopy. Surface chemical functionality of the nanocatalysts was investigated using X-ray photoelectron microscopy. Meanwhile, the ORR performance of nanocatalysts in a half cell were investigated using cyclic voltammetry techniques in both alkaline and acidic electrolytes. From this study, agglomeration of functionalised graphene (f-graphene was observed on the Fe-NCNTs indicating a hindrance in transfer of electrons within the catalyst surface. NCNT/f-graphene showed to contain higher percentage of pyridinic-N which claimed to have favored the catalytic activity compared to Fe-NCNT/f-graphene. Likewise, a higher onset potential was recorded for NCNT/f-graphene which indicated a higher ORR activity than the Fe-NCNT/f-graphene.

Higgs Physics

CERN Document Server

Pomarol, Alex

2016-01-01

With the discovery of the Higgs, we have access to a plethora of new physical processes that allow us to further test the SM and beyond. We show a convenient way to parametrize these physics using an effective theory for Higgs couplings, discussing the importance of the basis selection, predictions from a SM effective field theory, and possible ways to measure these couplings with special attention to the high-energy regime. Predictions from the MSSM and MCHM, with the comparison with data, are also provided.

Nuclear Physics Laboratory 1980 annual report

International Nuclear Information System (INIS)

Adelberger, E.G.

1980-09-01

Research progress is reported in the following areas: astrophysics and cosmology, fundamental symmetries, nuclear structure and reactions, radiative capture, medium energy physics, heavy ion reactions, research by outside users, accelerators and ion sources, instrumentation and experimental techniques, and computers and computing. Publications are listed

Nuclear Physics Laboratory 1980 annual report

Energy Technology Data Exchange (ETDEWEB)

Adelberger, E.G. (ed.)

1980-09-01

Research progress is reported in the following areas: astrophysics and cosmology, fundamental symmetries, nuclear structure and reactions, radiative capture, medium energy physics, heavy ion reactions, research by outside users, accelerators and ion sources, instrumentation and experimental techniques, and computers and computing. Publications are listed. (WHK)

On the mechanism of effective chemical reactions with turbulent mixing of reactants and finite rate of molecular reactions

Energy Technology Data Exchange (ETDEWEB)

Vorotilin, V. P., E-mail: VPVorotilin@yandex.ru [Russian Academy of Sciences, Institute of Applied Mechanics (Russian Federation)

2017-01-15

A generalization of the theory of chemical transformation processes under turbulent mixing of reactants and arbitrary values of the rate of molecular reactions is presented that was previously developed for the variant of an instantaneous reaction [13]. The use of the features of instantaneous reactions when considering the general case, namely, the introduction of the concept of effective reaction for the reactant volumes and writing a closing conservation equation for these volumes, became possible due to the partition of the whole amount of reactants into “active” and “passive” classes; the reactants of the first class are not mixed and react by the mechanism of instantaneous reactions, while the reactants of the second class approach each other only through molecular diffusion, and therefore their contribution to the reaction process can be neglected. The physical mechanism of reaction for the limit regime of an ideal mixing reactor (IMR) is revealed and described. Although formally the reaction rate in this regime depends on the concentration of passive fractions of the reactants, according to the theory presented, the true (hidden) mechanism of the reaction is associated only with the reaction of the active fractions of the reactants with vanishingly small concentration in the volume of the reactor. It is shown that the rate constant of fast chemical reactions can be evaluated when the mixing intensity of reactants is much less than that needed to reach the mixing conditions in an IMR.

Instantaneous formation of SiOx nanocomposite for high capacity lithium ion batteries by enhanced disproportionation reaction during plasma spray physical vapor deposition.

Science.gov (United States)

Tashiro, Tohru; Dougakiuchi, Masashi; Kambara, Makoto

2016-01-01

Nanocomposite SiO x particles have been produced by a single step plasma spray physical vapor deposition (PS-PVD) through rapid condensation of SiO vapors and the subsequent disproportionation reaction. Core-shell nanoparticles, in which 15 nm crystalline Si is embedded within the amorphous SiO x matrix, form under typical PS-PVD conditions, while 10 nm amorphous particles are formed when processed with an increased degree of non-equilibrium effect. Addition of CH 4 promotes reduction in the oxygen content x of SiO x , and thereby increases the Si volume in a nanocomposite particle. As a result, core-shell nanoparticles with x  = 0.46 as anode exhibit increased initial efficiency and the capacity of lithium ion batteries while maintaining cyclability. Furthermore, it is revealed that the disproportionation reaction of SiO is promoted in nanosized particles attaining increased Si diffusivity by two orders of magnitude compared to that in bulk, which facilitates instantaneous composite nanoparticle formation during PS-PVD.

Pathways for the OH + Br2 → HOBr + Br and HOBr + Br → HBr + BrO Reactions.

Science.gov (United States)

Wang, Hongyan; Qiu, Yudong; Schaefer, Henry F

2016-02-11

The OH radical reaction with Br2 and the subsequent reaction HOBr + Br are of exceptional importance to atmospheric chemistry and environmental chemistry. The entrance complex, transition state, and exit complex for both reactions have been determined using the coupled-cluster method with single, double, and perturbative triple excitations CCSD(T) with correlation consistent basis sets up to size cc-pV5Z and cc-pV5Z-PP. Coupled cluster effects with full triples (CCSDT) and full quadruples (CCSDTQ) are explicitly investigated. Scalar relativistic effects, spin-orbit coupling, and zero-point vibrational energy corrections are evaluated. The results from the all-electron basis sets are compared with those from the effective core potential (ECP) pseudopotential (PP) basis sets. The results are consistent. The OH + Br2 reaction is predicted to be exothermic 4.1 ± 0.5 kcal/mol, compared to experiment, 3.9 ± 0.2 kcal/mol. The entrance complex HO···BrBr is bound by 2.2 ± 0.2 kcal/mol. The transition state lies similarly well below the reactants OH + Br2. The exit complex HOBr···Br is bound by 2.7 ± 0.6 kcal/mol relative to separated HOBr + Br. The endothermicity of the reaction HOBr + Br → HBr + BrO is 9.6 ± 0.7 kcal/mol, compared with experiment 8.7 ± 0.3 kcal/mol. For the more important reverse (exothermic) HBr + BrO reaction, the entrance complex BrO···HBr is bound by 1.8 ± 0.6 kcal/mol. The barrier for the HBr + BrO reaction is 6.8 ± 0.9 kcal/mol. The exit complex (Br···HOBr) for the HBr + BrO reaction is bound by 1.9 ± 0.2 kcal/mol with respect to the products HOBr + Br.

Nuclear Physics Division - Inst. of Experimental Physics - Warsaw University - Annual Report 2003

International Nuclear Information System (INIS)

Kirejczyk, M.; Skwira, I.; Grodner, E.

2004-01-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Warsaw University Institute of Experimental Physics in year of 2003 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one contain the lists of personnel, seminars held at the Nuclear Physics Division and list of published papers. A summary of the (NPD) activities are briefly presented in ''Preface'' written by NPD director prof. K. Siwek-Wilczynska

Nuclear Physics Division - Inst. of Experimental Physics - Warsaw University - Annual Report 1998

International Nuclear Information System (INIS)

Kirejczyk, M.; Szeflinski, Z.

1999-01-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Warsaw University Institute of Experimental Physics in year of 1998 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one contains the lists of personnel, seminars held at the Nuclear Physics Division and list of published papers. A summary of the (NPD) activities are briefly presented in ''Preface'' written by NDP director prof. K. Siwek-Wilczynska

Nuclear Physics Division - Inst. of Experimental Physics - Warsaw University - Annual Report 2004

International Nuclear Information System (INIS)

Kirejczyk, M.K.

2005-01-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Warsaw University Institute of Experimental Physics in year of 2004 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one contains the lists of personnel, seminars held at the Nuclear Physics Division and list of published papers. A summary of the (NPD) activities are briefly presented in ''Preface'' written by NDP director prof. K. Siwek-Wilczynska

Nuclear Physics Division - Inst. of Experimental Physics - Warsaw University - Annual Report 1998

Energy Technology Data Exchange (ETDEWEB)

Kirejczyk, M.; Szeflinski, Z. [eds.

1999-08-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Warsaw University Institute of Experimental Physics in year of 1998 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one contains the lists of personnel, seminars held at the Nuclear Physics Division and list of published papers. A summary of the (NPD) activities are briefly presented in ``Preface`` written by NDP director prof. K. Siwek-Wilczynska

Nuclear Physics Division - Inst. of Experimental Physics - Warsaw University - Annual Report 2000

International Nuclear Information System (INIS)

Kirejczyk, M.

2001-01-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Warsaw University Institute of Experimental Physics in year of 2000 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one contain the lists of personnel, seminars held at the Nuclear Physics Division and list of published papers. A summary of the (NPD) activities are briefly presented in 'Preface' written by NDP director prof. K. Siwek-Wilczynska

Nuclear Physics Division - Inst. of Experimental Physics - Warsaw University - Annual Report 2001

International Nuclear Information System (INIS)

Kirejczyk, M.

2001-01-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Warsaw University Institute of Experimental Physics in year of 2001 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one which contain the lists of personnel, seminars held at the Nuclear Physics Division and list of published papers. A summary of the (NPD) activities are briefly presented in ''Preface'' written by NPD director prof. K. Siwek-Wilczynska

Nuclear Physics Division - Inst. of Experimental Physics - Warsaw University - Annual Report 1999

International Nuclear Information System (INIS)

Kirejczyk, M.

2000-01-01

In the presented report the research activities of Nuclear Physics Division (NPD) of the Warsaw University Institute of Experimental Physics in year of 1999 are described. The report is divided into three parts: Reaction Mechanisms and Nuclear Structure, Experimental Methods and Instrumentation and the third one contain the lists of personnel, seminars held at the Nuclear Physics Division and list of published papers. A summary of the (NPD) activities are briefly presented in ''Preface'' written by NDP director prof. K. Siwek-Wilczynska

Exploratory study of nuclear reaction data utility framework of Japan charged particle reaction data group (JCPRG)

International Nuclear Information System (INIS)

Masui, Hiroshi; Ohnishi, Akira; Kato, Kiyoshi; Ohbayasi, Yosihide; Aoyama, Shigeyoshi; Chiba, Masaki

2002-01-01

Compilation, evaluation and dissemination are essential pieces of work for the nuclear data activities. We, Japan charged particle data group, have researched the utility framework for the nuclear reaction data on the basis of recent progress of computer and network technologies. These technologies will be not only for the data dissemination but for the compilation and evaluation assistance among the many corresponding researchers of all over the world. In this paper, current progress of our research and development is shown. (author)

Gas-Phase Reaction Pathways and Rate Coefficients for the Dichlorosilane-Hydrogen and Trichlorosilane-Hydrogen Systems

Science.gov (United States)

Dateo, Christopher E.; Walch, Stephen P.

2002-01-01

As part of NASA Ames Research Center's Integrated Process Team on Device/Process Modeling and Nanotechnology our goal is to create/contribute to a gas-phase chemical database for use in modeling microelectronics devices. In particular, we use ab initio methods to determine chemical reaction pathways and to evaluate reaction rate coefficients. Our initial studies concern reactions involved in the dichlorosilane-hydrogen (SiCl2H2--H2) and trichlorosilane-hydrogen (SiCl2H-H2) systems. Reactant, saddle point (transition state), and product geometries and their vibrational harmonic frequencies are determined using the complete-active-space self-consistent-field (CASSCF) electronic structure method with the correlation consistent polarized valence double-zeta basis set (cc-pVDZ). Reaction pathways are constructed by following the imaginary frequency mode of the saddle point to both the reactant and product. Accurate energetics are determined using the singles and doubles coupled-cluster method that includes a perturbational estimate of the effects of connected triple excitations (CCSD(T)) extrapolated to the complete basis set limit. Using the data from the electronic structure calculations, reaction rate coefficients are obtained using conventional and variational transition state and RRKM theories.

Polymerase chain reaction for the detection of Mycobacterium leprae

NARCIS (Netherlands)

Hartskeerl, R. A.; de Wit, M. Y.; Klatser, P. R.

1989-01-01

A polymerase chain reaction (PCR) using heat-stable Taq polymerase is described for the specific detection of Mycobacterium leprae, the causative agent of leprosy. A set of primers was selected on the basis of the nucleotide sequence of a gene encoding the 36 kDa antigen of M. leprae. With this set

Heavy-ion reactions and new trends of nuclear Physics

International Nuclear Information System (INIS)

Bernas, M.

1987-06-01

On the chart of the nuclei, there are still areas which would deserve to be explored like the Nickel hole on the neutron rich side. We shall illustrate here the progress recently accomplished along this line and compare resulting datas with Hartree Fock Bogoliubov (H.F.B.) calculations performed on those isotopes. It is shown how well-known production reactions like quasi elastic transfer or neutron induced fission have been pushed toward their limits, thanks to improvements in experimental devices, to be usable further apart from stability

Effect of projectile on incomplete fusion reactions at low energies

Directory of Open Access Journals (Sweden)

Sharma Vijay R.

2017-01-01

Full Text Available Present work deals with the experimental studies of incomplete fusion reaction dynamics at energies as low as ≈ 4 - 7 MeV/A. Excitation functions populated via complete fusion and/or incomplete fusion processes in 12C+175Lu, and 13C+169Tm systems have been measured within the framework of PACE4 code. Data of excitation function measurements on comparison with different projectile-target combinations suggest the existence of ICF even at slightly above barrier energies where complete fusion (CF is supposed to be the sole contributor, and further demonstrates strong projectile structure dependence of ICF. The incomplete fusion strength functions for 12C+175Lu, and 13C+169Tm systems are analyzed as a function of various physical parameters at a constant vrel ≈ 0.053c. It has been found that one neutron (1n excess projectile 13C (as compared to 12C results in less incomplete fusion contribution due to its relatively large negative α-Q-value, hence, α Q-value seems to be a reliable parameter to understand the ICF dynamics at low energies. In order to explore the reaction modes on the basis of their entry state spin population, the spin distribution of residues populated via CF and/or ICF in 16O+159Tb system has been done using particle-γ coincidence technique. CF-α and ICF-α channels have been identified from backward (B and forward (F α-gated γspectra, respectively. Reaction dependent decay patterns have been observed in different α emitting channels. The CF channels are found to be fed over a broad spin range, however, ICF-α channels was observed only for high-spin states. Further, the existence of incomplete fusion at low bombarding energies indicates the possibility to populate high spin states

Effect of projectile on incomplete fusion reactions at low energies

Science.gov (United States)

Sharma, Vijay R.; Shuaib, Mohd.; Yadav, Abhishek; Singh, Pushpendra P.; Sharma, Manoj K.; Kumar, R.; Singh, Devendra P.; Singh, B. P.; Muralithar, S.; Singh, R. P.; Bhowmik, R. K.; Prasad, R.

2017-11-01

Present work deals with the experimental studies of incomplete fusion reaction dynamics at energies as low as ≈ 4 - 7 MeV/A. Excitation functions populated via complete fusion and/or incomplete fusion processes in 12C+175Lu, and 13C+169Tm systems have been measured within the framework of PACE4 code. Data of excitation function measurements on comparison with different projectile-target combinations suggest the existence of ICF even at slightly above barrier energies where complete fusion (CF) is supposed to be the sole contributor, and further demonstrates strong projectile structure dependence of ICF. The incomplete fusion strength functions for 12C+175Lu, and 13C+169Tm systems are analyzed as a function of various physical parameters at a constant vrel ≈ 0.053c. It has been found that one neutron (1n) excess projectile 13C (as compared to 12C) results in less incomplete fusion contribution due to its relatively large negative α-Q-value, hence, α Q-value seems to be a reliable parameter to understand the ICF dynamics at low energies. In order to explore the reaction modes on the basis of their entry state spin population, the spin distribution of residues populated via CF and/or ICF in 16O+159Tb system has been done using particle-γ coincidence technique. CF-α and ICF-α channels have been identified from backward (B) and forward (F) α-gated γspectra, respectively. Reaction dependent decay patterns have been observed in different α emitting channels. The CF channels are found to be fed over a broad spin range, however, ICF-α channels was observed only for high-spin states. Further, the existence of incomplete fusion at low bombarding energies indicates the possibility to populate high spin states

The 8Li(α,n)11B reaction and primordial nucleosynthesis

International Nuclear Information System (INIS)

Boyd, R.N.

1992-01-01

The cross section for the 8 Li(α,n) 11 B reaction, of importance to synthesis of 11 B and heavier nuclides following the big bang, has been measured using the radioactive beam facility of The Institute of Physical and Chemical Reasearch (RIKEN). The reaction cross section was found to be about five times larger than that estimated from the time reversed reaction cross section. (author)

Child physical abuse and the related PTSD in Taiwan: The role of Chinese cultural background and victims' subjective reactions.

Science.gov (United States)

Chou, Chia-Ying; Su, Yi-Jen; Wu, Ho-Mao; Chen, Sue-Huei

2011-01-01

This study aimed to investigate child physical abuse (CPA) while taking into account the more rigorous definitions of CPA in the Chinese societies. The prevalence of CPA and CPA-related PTSD were estimated, together with the examination of peri-traumatic subjective reactions and their impacts on PTSD. In a Taiwanese sample of 1966 4th to 8th graders, the Chinese version of UCLA PTSD Reaction Index for DSM-IV (Steinberg, Brymer, Decker, & Pynoos, 2004) was used to investigate the lifetime exposure to CPA. A sub-sample of 236 traumatized CPA victims was examined with respect to related PTSD symptoms. Thirty-four percent of the children had been exposed to CPA. The estimated current prevalence of full and partial PTSD was 13.6% and 16.9%, respectively. The current CPA prevalence was found to be higher than the Western countries, but lower than the previous findings in other East Asian societies. The full PTSD prevalence was close to the findings in the Western countries, whereas sub-clinical PTSD was less observed in Taiwan. Peri-traumatic subjective reactions, that is, Criterion A2 and perceived threat, were shown to be major predictors of PTSD symptom severity. The role of attitudes of child discipline in the Chinese societies in the prevalence of CPA and CPA-related PTSD is discussed. By providing explicit epidemiological information of CPA and CPA-related PTSD in Taiwan, the current study extends our understanding of CPA and CPA-related PTSD more broadly from Western countries to the Eastern societies. By separately investigating CPA relating to different perpetrators, cross-study comparison is enhanced. In the current study, the significance of considering cultural background in defining CPA and examining CPA-related PTSD was pointed out. Meanwhile, the role of victims' subjective reactions in the psychopathology of PTSD is highlighted. The findings and discussions could contribute for generating a more sophisticated clinical practice, especially with Asian or

Simulation of Chemical Reaction Equilibria by the Reaction Ensemble Monte Carlo Method:

Czech Academy of Sciences Publication Activity Database

Turner, C.H.; Brennan, J.K.; Lísal, Martin; Smith, W.R.; Johnson, J. K.; Gubbins, K.E.

2008-01-01

Roč. 34, č. 2 (2008), s. 119-146 ISSN 0892-7022 R&D Projects: GA AV ČR KAN400720701; GA ČR GA203/05/0725; GA AV ČR IAA400720710; GA AV ČR 1ET400720507 Grant - others:NRCC(CA) OGP1041 Institutional research plan: CEZ:AV0Z40720504 Keywords : simulation * review * reaction equilibria Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.325, year: 2008

Stellar evolution and the triple-α reactions

International Nuclear Information System (INIS)

Suda, Takuma

2014-01-01

Nuclear reaction rates play a crucial role in the evolution of stars. For low-mass stars, the triple-α reaction controls the helium burning stars in the red giant and asymptotic giant branch (AGB) phase. More importantly, the cross section of the triple-α reaction has a great impact on the helium ignition at the center of the electron degenerate helium core of red giants and on the helium shell flashes of AGB stars. It is to be noted that stellar evolution models are influenced not only by the value of the cross section, but also by the temperature dependence of the reaction rate. In this paper, I present the impact of the triple-α reaction rates on the evolution of low-mass metal-free stars and intermediate-mass AGB stars. According to the previous study, the constraint on the triple-α reaction rate is derived based on stellar evolution theory. It is found that the recent revisions of the rate proposed by nuclear physics calculations satisfy the condition for the ignition of the helium core flash in low-mass stars

Physics Division annual review, 1 April 1978-31 March 1979

Energy Technology Data Exchange (ETDEWEB)

None

1979-01-01

A broad review is presented of work in the areas of nuclear physics research (the superconducting linac; medium-energy physics; heavy-ion research at the tandem and superconducting linac accelerators - resonant structures in heavy-ion reactions, fusion cross sections, high-angular-momentum-states in nuclei; charged-particle research; accelerator operations and development; neutron and photonuclear physics; theoretical physics - heavy-ion direct reactions, nuclear shell theory and nuclear structure, nuclear matter, intermediate-energy physics, dense nuclear matter and classical calculations of the high-energy collisions of heavy ions; radiative transitions and nuclear resonance reactions experimental atomic and molecular physics research (dissociation and other interactions of energetic molecular ions in solid and gaseous targets, beam-foil research and collision dynamics of heavy ions, photoionization-photon-electron research, spectroscopy of free atoms, Moessbauer effect research, monochromatic x-ray beam project); and applied physics (interaction of energetic particles with solids scanning secondary-ion microprobe). Most of the reports are quite brief (about a page); 24 pages of references are included. 21 items with significant amounts of information are abstracted individually. (RWR)

Department of Nuclear Reactions: Overview

International Nuclear Information System (INIS)

Rusek, K.

2003-01-01

Full text: In 2002, the Department has been involved in two new experimental programmes. Our colleagues led by Prof. Pawel Zupranski joined a large international collaboration HERMES and took part in experiments at DESY devoted to the study of the spin structure of the nucleon. Another group directed by Associate Prof. Bogdan Zwieglinski has worked on a conceptual design of a new generation detector PANDA (Proton-Antiproton Detection) which will be used in future experiments at GSI. Moreover, the experimental programmes covering three major domains of our scientific activities: nuclear physics, materials research and atomic physics were continued. - Nuclear physics: Experimental studies of nuclear reactions induced by heavy ions provided by the Warsaw U-200P Cyclotron were performed in collaboration with scientists from the Institute for Nuclear Studies in Kiev, Ukraine. The aim of the experiments was to investigate isotopic effects in the scattering of 11 B from carbon nuclides. Also, excited states of 6 Li predicted theoretically but never seen in experiments were investigated by means of one-neutron transfer reactions. Proton induced reactions were investigated theoretically by means of the multistep-direct model. Good agreement with the experimental data was achieved. The mechanism of fragments production in collisions of 197 Au with a gold target in the wide range of energies was studied by ALADIN and INDRA Collaborations. The production of η mesons from proton - proton collisions was investigated experimentally at the Juelich Cooler Synchrotron COSY. - Atomic physics: The ionisation of Au, Bi, Th and U atoms by Si ions was investigated in collaboration with the Swietokrzyska Academy, Kielce, and the University of Erlangen-Nuernberg. - Materials research: The sensitivity of the Solid State Nuclear Track PM-355 detectors was tested against intensive gamma and electron radiation. Moreover, using a monoenergetic sulphur ion beam from the Warsaw Cyclotron, the

Physical and economical aspects of Pu multiple recycling on the basis of REMIX reprocessing technology in thermal reactors

International Nuclear Information System (INIS)

Teplov, P.S.; Alekseev, P.N.; Bobrov, E.A.; Chibinyaev, A.V.

2016-01-01

The basic strategy of Russian nuclear energy is propagation of a closed fuel cycle on the basis of fast breeder and thermal reactors, as well as the solution of the spent nuclear fuel accumulation and resource problems. The 3 variants of multiple Pu and U recycling in Russian pressurized water reactor concept reactors on the basis of Regenerated Mixture of U, Pu oxides (REMIX) reprocessing technology are considered in this work. The REMIX fuel is fabricated from an un-separated mixture of uranium and plutonium obtained during spent fuel reprocessing with further makeup by enriched natural U or reactor grade Pu. This makes it possible to recycle several times the total amount of Pu obtained from the spent fuel. The main difference in Pu recycling is the concept of 100% or partial fuel loading of the core. The third variant is heterogeneous composition of enriched uranium and uranium-plutonium mixed oxide fuel pins in one fuel assembly. It should be noted that all fuel assemblies with Pu require the involvement of expensive technologies during manufacturing. These 3 variants of the full core loadings can be balanced on zero Pu accumulation in the cycle. The various physical and economical aspects of Pu and U multiple recycling in selected variants are presented in the given work. The better results in natural uranium savings can be achieved for the standard REMIX(UOX) approach. The usage of regenerated materials in thermal power reactors gives not more than 30% saving of natural uranium consumption. It is important to note that the use of REMIX technology in the closed fuel cycle is more expensive than the open fuel cycle with direct spent fuel disposal. It is also important to see that uranium multiple recycling in the REMIX fuel form or using the re-enrichment process leads to the degradation of the uranium isotope composition. The "2"3"6U and "2"3"2U concentrations in the fuel are increasing and the regenerated uranium treatment becomes more complicated

Physics Division annual review, 1 April 1983-31 March 1984

International Nuclear Information System (INIS)

1984-08-01

A broad but necessarily incomplete review of the research activities within the Division is presented. Activities in medium-energy physics research include studies of pion reaction mechanisms, nuclear structure studies, two-nucleon physics with pions and electrons, weak interactions and particle searches. Research at the Superconducting Linac Accelerator includes studies on quasi-elastic processes and reaction strengths, heavy-ion fusion reactions, high angular momentum states in nuclei, accelerator mass spectrometry and equipment development at the Tandem-Linac Facility. Theoretical nuclear physics studies reviewed are grouped in the areas: nuclear forces and subnucleon degrees of freedom, variational calculation of finite many-body systems, nuclear shell theory and nuclear structure, intermediate energy physics, heavy-ion reactions and other theoretical studies. The status of the superconducting linac program is detailed, and operation and development of the tandem-linac accelerator and the Dynamitron Facility are described. The atomic and molecular physics research is detailed in the five ongoing programs: photoionization-photoelectron research, high-resolution laser-rf spectroscopy with atomic and molecular beams, photon interactions involving fast ions, interactions of fast atomic and molecular ions with solid and gaseous targets, and theoretical atomic physics. A complete list of publications and the Division roster are included

Physics with energetic radioactive ion beams

International Nuclear Information System (INIS)

Henning, W.F.

1996-01-01

Beams of short-lived, unstable nuclei have opened new dimensions in studies of nuclear structure and reactions. Such beams also provide key information on reactions that take place in our sun and other stars. Status and prospects of the physics with energetic radioactive beams are summarized

Real-time virtual EAST physical experiment system

Energy Technology Data Exchange (ETDEWEB)

Li, Dan, E-mail: lidan@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui (China); Xiao, B.J., E-mail: bjxiao@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui (China); School of Nuclear Science and Technology, University of Science and Technology of China, Hefei, Anhui (China); Xia, J.Y., E-mail: jyxia@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui (China); Yang, Fei, E-mail: fyang@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui (China); Department of Computer Science, Anhui Medical University, Hefei, Anhui (China)

2014-05-15

Graphical abstract: - Highlights: • 3D model of experimental advanced superconducting tokamak is established. • Interaction behavior is created that the users can get information from database. • The system integrates data acquisition, plasma shape visualization and simulation. • Browser-oriented system is web-based and more interactive, immersive and convenient. • The system provides the framework for virtual physical experimental environment. - Abstract: As a large fusion reaction device, experimental advanced superconducting tokamak (EAST)’s internal structure is complicated and not easily accessible. Moreover, various diagnostic systems and complicated configuration bring about the inconveniency to the scientists who are unfamiliar with the system but interested in the data. We propose a virtual system to display the 3D model of EAST facility and enable people to view its inner structure and get access to the information of its components in various view sights. We would also provide most of the diagnostic configuration details together with their signal names and physical properties. Compared to the previous ways of viewing information by reference to collected drawings and videos, virtual EAST system is more interactive and immersive. We constructed the browser-oriented virtual EAST physical experiment system, integrated real-time experiment data acquisition, plasma shape visualization and experiment result simulation in order to reproduce physical experiments in a web browser. This system used B/S (Browser/Server) structure in combination with the technology of virtual reality – VRML (Virtual Reality Modeling Language) and Java 3D. In order to avoid the bandwidth limit across internet, we balanced the rendering speed and the precision of the virtual model components. Any registered user can view the experimental information visually and efficiently by logining the system through a web browser. The establishment of the system provides the

Real-time virtual EAST physical experiment system

International Nuclear Information System (INIS)

Li, Dan; Xiao, B.J.; Xia, J.Y.; Yang, Fei

2014-01-01

Graphical abstract: - Highlights: • 3D model of experimental advanced superconducting tokamak is established. • Interaction behavior is created that the users can get information from database. • The system integrates data acquisition, plasma shape visualization and simulation. • Browser-oriented system is web-based and more interactive, immersive and convenient. • The system provides the framework for virtual physical experimental environment. - Abstract: As a large fusion reaction device, experimental advanced superconducting tokamak (EAST)’s internal structure is complicated and not easily accessible. Moreover, various diagnostic systems and complicated configuration bring about the inconveniency to the scientists who are unfamiliar with the system but interested in the data. We propose a virtual system to display the 3D model of EAST facility and enable people to view its inner structure and get access to the information of its components in various view sights. We would also provide most of the diagnostic configuration details together with their signal names and physical properties. Compared to the previous ways of viewing information by reference to collected drawings and videos, virtual EAST system is more interactive and immersive. We constructed the browser-oriented virtual EAST physical experiment system, integrated real-time experiment data acquisition, plasma shape visualization and experiment result simulation in order to reproduce physical experiments in a web browser. This system used B/S (Browser/Server) structure in combination with the technology of virtual reality – VRML (Virtual Reality Modeling Language) and Java 3D. In order to avoid the bandwidth limit across internet, we balanced the rendering speed and the precision of the virtual model components. Any registered user can view the experimental information visually and efficiently by logining the system through a web browser. The establishment of the system provides the

PHYSICS

CERN Multimedia

J. Incandela

The all-plenary format of the CMS week in Cyprus gave the opportunity to the conveners of the physics groups to present the plans of each physics analysis group for tackling early physics analyses. The presentations were complete, so all are encouraged to browse through them on the Web. There is a wealth of information on what is going on, by whom and on what basis and priority. The CMS week was followed by two CMS “physics events”, the ICHEP08 days and the physics days in July. These were two weeks dedicated to either the approval of all the results that would be presented at ICHEP08, or to the review of all the other Monte-Carlo based analyses that were carried out in the context of our preparations for analysis with the early LHC data (the so-called “2008 analyses”). All this was planned in the context of the beginning of a ramp down of these Monte Carlo efforts, in anticipation of data.  The ICHEP days are described below (agenda and talks at: http://indic...

Physical basis of coastal productivity: The SEEP and MASAR experiments

Science.gov (United States)

Csanady, G. T.

Two major cooperative experiments, code-named Shelf Edge Exchange Processes (SEEP) I and II, were carried out on the northeast U.S. continental shelf and slope by an interdisciplinary group of scientists in the past decade. The work, supported by the Department of Energy, Office of Health and Environmental Research, had the broad aim of determining whether or to what extent energy-related human activities interfere with the high biological productivity of coastal waters. Much of SEEP I work was reported in a dedicated issue of Continental Shelf Research, including a summary article on the experiment as a whole [Walsh et al., 1988[. A parallel experiment, supported by the Minerals Management Service and code-named Mid Atlantic Slope and Rise (MASAR), had the objective of exploring physical processes over the continental slope and rise, including especially currents in the upper part of the water column. A good deal of MASAR work was also reported in the SEEP issue just mentioned, mainly in an article by Csanady and Hamilton (1988). There have been other papers and publications on these experiments, and more are forthcoming. While many questions remain, our horizons have broadened considerably after a decade of work on this problem, as if our aeroplane had just emerged from clouds to expose an interesting landscape. In this article I shall try to describe the physical (-oceanographic) features of that landscape, not in the chronological order in which we have espied them, but as the logic of the subject dictates.

METHODOLOGICAL BASIS FOR CREATING AN ELECTRONIC APPLICATION TO THE TEXTBOOK "PHYSICS 9"

OpenAIRE

L.U. Blagodarenko

2010-01-01

The results of the analysis of educational software that exist on the Ukrainian market are presented. The structure, functions and advantages of the electronic application to the textbook "Physics 9" are defined.

Experimental nuclear physics in Vietnam - recent status

International Nuclear Information System (INIS)

Tran Thanh Minh

1995-01-01

Status of research works on experimental nuclear physics in Vietnam is reviewed. Vietnam institutions and main instruments for nuclear research are listed. The results on physics and technology of nuclear reactor, neutron physics, nuclear reactions, radiological safety are mentioned. (N.H.A). 6 tabs, 4 figs

Stringed converters on a basis of Ge1-xSix monocrystals

International Nuclear Information System (INIS)

Abbasov, Sh.M.; Abbasov, Sh. I.; Baytsar, R.I

2003-01-01

Full Text: The representing electromechanical resonator on elastic vibrations of monocrystal strings from semiconductor materials rather simple in manufacturing of stringed tenzoconverter on the basis of Ge-Si monocrystals was described. The examples os such class of converters using in concrete designs of devices for measurement of various physical parameters were reported

Multistage reaction pathways in detonating high explosives

International Nuclear Information System (INIS)

Li, Ying; Kalia, Rajiv K.; Nakano, Aiichiro; Nomura, Ken-ichi; Vashishta, Priya

2014-01-01

Atomistic mechanisms underlying the reaction time and intermediate reaction products of detonating high explosives far from equilibrium have been elusive. This is because detonation is one of the hardest multiscale physics problems, in which diverse length and time scales play important roles. Here, large spatiotemporal-scale reactive molecular dynamics simulations validated by quantum molecular dynamics simulations reveal a two-stage reaction mechanism during the detonation of cyclotrimethylenetrinitramine crystal. Rapid production of N 2 and H 2 O within ∼10 ps is followed by delayed production of CO molecules beyond ns. We found that further decomposition towards the final products is inhibited by the formation of large metastable carbon- and oxygen-rich clusters with fractal geometry. In addition, we found distinct unimolecular and intermolecular reaction pathways, respectively, for the rapid N 2 and H 2 O productions

Multistage reaction pathways in detonating high explosives

Energy Technology Data Exchange (ETDEWEB)

Li, Ying [Collaboratory for Advanced Computing and Simulations, Department of Physics and Astronomy, Department of Computer Science, and Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089-0242 (United States); Argonne Leadership Computing Facility, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Kalia, Rajiv K.; Nakano, Aiichiro; Nomura, Ken-ichi; Vashishta, Priya [Collaboratory for Advanced Computing and Simulations, Department of Physics and Astronomy, Department of Computer Science, and Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089-0242 (United States)

2014-11-17

Atomistic mechanisms underlying the reaction time and intermediate reaction products of detonating high explosives far from equilibrium have been elusive. This is because detonation is one of the hardest multiscale physics problems, in which diverse length and time scales play important roles. Here, large spatiotemporal-scale reactive molecular dynamics simulations validated by quantum molecular dynamics simulations reveal a two-stage reaction mechanism during the detonation of cyclotrimethylenetrinitramine crystal. Rapid production of N{sub 2} and H{sub 2}O within ∼10 ps is followed by delayed production of CO molecules beyond ns. We found that further decomposition towards the final products is inhibited by the formation of large metastable carbon- and oxygen-rich clusters with fractal geometry. In addition, we found distinct unimolecular and intermolecular reaction pathways, respectively, for the rapid N{sub 2} and H{sub 2}O productions.

Interim safety basis compliance matrix for Trenches 31 and 34

International Nuclear Information System (INIS)

Ames, R.R.

1994-01-01

The tables provided in this document identify the specific requirements and basis for the administrative controls established in the Westinghouse Hanford Company (WHC) Solid Waste Burial Ground (SWBG) Interim Safety Basis (ISB) for operation of the Project W-025, Mixed Waste Lined Landfill (Trenches 31 and 34). The tables document the necessary controls and implementing procedures to ensure compliance with the requirements of the ISB. These requirements provide a basis for future Unreviewed Safety Questions (USQ) screening of applicable procedure changes, proposed physical modifications, tests, experiments, and occurrences. Table 1 provides the SWBG interim Operational Safety Requirements administrative controls matrix. The specific assumptions and commitments used in the safety analysis documents applicable to disposal of mixed wastes in Trenches 31 and 34 are provided in Table 2. Table 3 is provided to document the potential engineered and administrative mitigating features identified in the Preliminary Hazard Analysis (PHA) for disposal of mixed waste

Thermal reactions of some calcium, strontium, and barium chromates

International Nuclear Information System (INIS)

Piekarska-Piesse, B.; Gontarz, Z.; Ostrowski, A.; Kucharski, R.

2000-01-01

Thermal decomposition of calcium chromates and solid state reactions of barium and strontium chromates(VI) with barium and strontium hydroxides and carbonates, as well as the reduction of chromates by carbon and hydrogen, have been investigated. The mechanisms of individual stages of the thermal decomposition have been proposed on the basis of morphological classification. (author)

Subpicosecond pulse radiolysis studies on spur reactions and nanotechnology

International Nuclear Information System (INIS)

Tagawa, S.

2003-01-01

Recently we developed a subpicosecond pulse radiolysis system, although the time resolution of pulse radiolysis had remained about 30 ps for these 30 years. Time resolution and S/N ratio have been improved dramatically. The subpicosecond pulse radiolysis is a very powerful method to detect and observe transient phenomena in radiation chemistry and physics within 30 ps. By using the subpicosecond pulse radiolysis, many researches have been carried out on ultrafast phenomena in radiation chemistry, physics, biology and applied fields such as material science.Especially the spur reaction, which is one of the most important reactions in radiation chemistry, physics and biology, has been studied in the very wide time range from subpicosecond to several hundred nanoseconds by very high S/N ratio. These experimental results were analyzed theoretically and applied to the basic data for nanofabrication, which are very important in both next generation lithography and nanotechnology

Charge-Transfer Reaction of Cediranib with 2,3-Dichloro- 3,5 ...

African Journals Online (AJOL)

5, 6- dicyano -1, 4 - benzoquinone (DDQ) and employment of the reaction as a basis for the development of a ... association constant of the complex was 0.5 × 103 L mol−1 in 2-propanol. ..... some substituted naphthoquinones. Bull Chem Soc.

Teachers' and students' reactions to the Revised Nuffield A-Level Physics Course (RNAP)

Science.gov (United States)

Sela, David

1990-07-01

difficult to achieve (understanding the nature of physical inquiry, learning to inquire, and being aware of the social significance of physics). An aim like `Developing practical skills' was highly rated by teachers but seemed to be much less important to students. Also the investigation was referred to much more positively by teachers than by the upper sixthform students (who had already experienced it). A suggested reason for this can be that teachers judged the investigation on its ideological basis, valuing its importance in scientific research, while the students were influenced by their actual results which were not always successful. We are not sure that these aims are treated better in another course. but taking into account some of these comments can improve the teaching of the course. In future it might also lead to a better version of RNAP which would be based more on real school situations, the influence of the GCSE and the teacher-student expectations.

Synthesis and Reactions of Five-Membered Heterocycles Using Phase Transfer Catalyst (PTC Techniques

Directory of Open Access Journals (Sweden)

Ahmed M. El-Sayed

2014-01-01

Full Text Available Phase transfer catalysts (PTCs have been widely used for the synthesis of organic compounds particularly in both liquid-liquid and solid-liquid heterogeneous reaction mixtures. They are known to accelerate reaction rates by facilitating formation of interphase transfer of species and making reactions between reagents in two immiscible phases possible. Application of PTC instead of traditional technologies for industrial processes of organic synthesis provides substantial benefits for the environment. On the basis of numerous reports it is evident that phase-transfer catalysis is the most efficient way for generation and reactions of many active intermediates. In this review we report various uses of PTC in syntheses and reactions of five-membered heterocycles compounds and their multifused rings.

Stability and dynamics of reactors with heterogeneously catalyzed reactions

Energy Technology Data Exchange (ETDEWEB)

Eigenberger, G [BASF A.G., Ludwigshafen am Rhein (Germany, F.R.)

1978-12-01

Our knowledge of causes and consequences of problems arising from instability and dynamic effects in reactors with heterogeneously catalyzed reactions has increased remarkably in recent years. Especially thermal effects, caused by the self-acceleration of an exothermic reaction in combination with heat and mass transport, are now well understood. In addition, kinetic effects, i.e. phenomena which have to be explained by the kinetic peculiarities of surface reactions, have attracted increasing interest. For both cases the state of the art will be reviewed, highlighting the physical and chemical causes of the observed phenomena.

METHODOLOGICAL BASIS FOR CREATING AN ELECTRONIC APPLICATION TO THE TEXTBOOK "PHYSICS 9"

Directory of Open Access Journals (Sweden)

L.U. Blagodarenko

2010-11-01

Full Text Available The results of the analysis of educational software that exist on the Ukrainian market are presented. The structure, functions and advantages of the electronic application to the textbook "Physics 9" are defined.

System requirements and design description for the document basis database interface (DocBasis)

International Nuclear Information System (INIS)

Lehman, W.J.

1997-01-01

This document describes system requirements and the design description for the Document Basis Database Interface (DocBasis). The DocBasis application is used to manage procedures used within the tank farms. The application maintains information in a small database to track the document basis for a procedure, as well as the current version/modification level and the basis for the procedure. The basis for each procedure is substantiated by Administrative, Technical, Procedural, and Regulatory requirements. The DocBasis user interface was developed by Science Applications International Corporation (SAIC)

Technical Basis for Physical Fidelity of NRC Control Room Training Simulators for Advanced Reactors

Energy Technology Data Exchange (ETDEWEB)

Minsk, Brian S.; Branch, Kristi M.; Bates, Edward K.; Mitchell, Mark R.; Gore, Bryan F.; Faris, Drury K.

2009-10-09

The objective of this study is to determine how simulator physical fidelity influences the effectiveness of training the regulatory personnel responsible for examination and oversight of operating personnel and inspection of technical systems at nuclear power reactors. It seeks to contribute to the U.S. Nuclear Regulatory Commission’s (NRC’s) understanding of the physical fidelity requirements of training simulators. The goal of the study is to provide an analytic framework, data, and analyses that inform NRC decisions about the physical fidelity requirements of the simulators it will need to train its staff for assignment at advanced reactors. These staff are expected to come from increasingly diverse educational and experiential backgrounds.

Prospects of hadron and quark physics with electromagnetic probes. Proceedings of the second ELFE workshop on Hadronic Physics

International Nuclear Information System (INIS)

D'Hose, N.; Frois, B.; Guichon, P.A.M.; Pire, B.; Van de Wiele, J.

1996-01-01

The last three days of the second ELFE workshop on confinement physics were devoted to the results of the work during the past year on the update and improvement of the physics case, the feasibility of the ELFE at DESY project (which combines the HERA ring used as a stretcher and a low duty factor 25 GeV electron linac which could be either a section of the TESLA collider or the injector of the foreseen short wave length free electron laser) as well as the development of the detectors. The participations have been decided into 5 copies: inclusive and semi-inclusive reactions; real photon physics, exclusive reactions; color transparency; detectors. (author)

Prospects of hadron and quark physics with electromagnetic probes. Proceedings of the second ELFE workshop on Hadronic Physics

Energy Technology Data Exchange (ETDEWEB)

D' Hose, N; Frois, B; Guichon, P A.M. [CEA Saclay, 91 - Gif-sur-Yvette (France). Dept. d' Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l' Instrumentation Associee; Pire, B [Ecole Polytechnique, 91 - Palaiseau (France). Centre de Physique Theorique; Van de Wiele, J [Institut de Physique Nucleaire, 91 - Orsay (France). Division de Recherche Experimentale

1996-07-01

The last three days of the second ELFE workshop on confinement physics were devoted to the results of the work during the past year on the update and improvement of the physics case, the feasibility of the ELFE at DESY project(which combines the HERA ring used as a stretcher and a low duty factor 25 GeV electron linac which could be either a section of the TESLA collider or the injector of the foreseen short wave length free electron laser) as well as the development of the detectors. The participations have been decided into 5 copies: inclusive and semi-inclusive reactions; real photon physics, exclusive reactions; color transparency; detectors. (author)

Thermodynamic analysis of dust sulphation reactions

Energy Technology Data Exchange (ETDEWEB)

Yang Yongxiang; Jokilaakso, A.

1997-12-31

Sulphation reactions of metal oxides with SO{sub 2} and O. or SO{sub 3} play significant roles in sulphation roasting of sulphide and oxide minerals as well as in desulphurisation process of combustion gases. In metallurgical waste-heat boilers for sulphide smelting, the sulphation of the oxidic flue dust in the atmosphere containing sulphur oxides is an unavoidable process, and the sulphation reactions have to be guided in a controlled way in the proper parts of the gas handling equipment. In this report, some thermodynamic analyses were conducted for the oxide sulphation reactions in relation to sulphide smelting processes. The phase stability of Me-S-O systems especially for oxides - sulphates equilibrium was studied under different thermodynamic conditions of gas compositions and temperatures. The sulphate stability was analysed for an example of gas compositions in the copper flash smelter of Outokumpu Harjavalta Metals Oy, in relation to temperature. In the report, most of the information was from literature. Moreover, a number of thermodynamic computations were carried out with the HSC program, and the constructed phase stability diagrams were compared with those from the literature whenever possible. The maximum temperatures for stable sulphates under normal operating conditions of the waste-heat boilers in sulphide smelting processes were obtained. This report will serve as the basis for the kinetic studies of the sulphation reactions and the sulphation reaction modelling in pyrometallurgical processes. (orig.) SULA 2 Programme. 36 refs.

New High-Precision Measurement of the Reaction Rate of the O-18(p, alpha)N-15 Reaction via THM

Czech Academy of Sciences Publication Activity Database

La Cognata, M.; Spitaleri, C.; Mukhamedzhanov, A. M.; Irgaziev, B.; Tribble, R. E.; Banu, A.; Cherubini, S.; Coc, A.; Crucilla, V.; Goldberg, V. Z.; Gulino, M.; Kiss, G. G.; Lamia, L.; Chengbo, L.; Mrázek, Jaromír; Pizzone, R. G.; Puglia, S. M. R.; Rapisarda, G. G.; Romano, S.; Sergi, M. L.; Tabacaru, G.; Trache, L.; Trzaska, W.; Tumino, A.

2009-01-01

Roč. 26, č. 3 (2009), s. 237-242 ISSN 1323-3580 Institutional research plan: CEZ:AV0Z10480505 Keywords : nuclear reactions * nucleosynthesis * abundances Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 3.786, year: 2009

Health physics aspects of the 1.5M cyclotron

International Nuclear Information System (INIS)

Song, W.J.; Du, H.L.; Wei, Z.Q.; Xia, X.S.; Zheng, H.Z.; Jiang, G.F.; Liu, Y.Y.

1987-01-01

The 1.5m cyclotron in Institute of Modern Physics, Academia Sinica had operated for about 20 years until 1984 then converted to 1.7m sector focusing cyclotron. In this period it mainly used for fast neutron physics, light ion induced nucleus reactions, radioisotope production and heavy ion reactions. The health physics performed on this cyclotron including personnel dose monitoring, area monitoring (radiation field, radioactive aerosol, surface contamination and activated components etc.), maintenance inspection, environment survey and waste disposal is presented in this paper

Open quantum system approach to the modeling of spin recombination reactions.

Science.gov (United States)

Tiersch, M; Steiner, U E; Popescu, S; Briegel, H J

2012-04-26

In theories of spin-dependent radical pair reactions, the time evolution of the radical pair, including the effect of the chemical kinetics, is described by a master equation in the Liouville formalism. For the description of the chemical kinetics, a number of possible reaction operators have been formulated in the literature. In this work, we present a framework that allows for a unified description of the various proposed mechanisms and the forms of reaction operators for the spin-selective recombination processes. On the basis of the concept that master equations can be derived from a microscopic description of the spin system interacting with external degrees of freedom, it is possible to gain insight into the underlying microscopic processes and develop a systematic approach toward determining the specific form of the reaction operator in concrete scenarios.

The Status of Physical Activity Opportunities in Idaho Schools

Science.gov (United States)

Berei, Catherine P.; Karp, Grace Goc; Kauffman, Katie

2018-01-01

Recent literature indicates that low percentages of Idaho adolescents report being physically active on a daily basis. Research examines school PA, however, little focuses on Comprehensive School Physical Activity Programs (CSPAPs) from the perspectives of physical educators. This study explored Idaho physical educators' perceptions and…

Waste-rock interactions and bedrock reactions

International Nuclear Information System (INIS)

White, W.B.

1977-01-01

The experimental program is designed to discover possible reactions between shale repository rocks and radioactive wastes. The canister can be regarded in three ways: (a) As a source of heat that modifies the mineralogy and therefore the physical properties of the surrounding rock (dry heat). (b) As a source of heat that activates reactions between minerals in the surrounding rock and slowly percolating ground water. (c) As a source of reaction materials of different composition from the surrounding rock and which therefore may react to form completely new ''minerals'' in a contact aureole around the canister. The matrix of interactions contains two composition axes. The waste compositions are defined by the various prototype waste forms usually investigated: glass, calcine, ''spent fuel'' and the ceramic supercalcine. The temperatures and pressures at which these reactions take place must be investigated. Thus each node on the ''wiring diagram'' is itself a matrix of experiments in which the T and to some extent P are varied. Experiments at higher pressure and temperature allow reactions to take place on a laboratory time scale and thus identify what could happen. These reactions are then followed downward in temperature to determine both phase boundaries and kinetic cut-offs below which equilibrium cannot be achieved on a laboratory time scale

Beam-hardening correction in CT based on basis image and TV model

International Nuclear Information System (INIS)

Li Qingliang; Yan Bin; Li Lei; Sun Hongsheng; Zhang Feng

2012-01-01

In X-ray computed tomography, the beam hardening leads to artifacts and reduces the image quality. It analyzes how beam hardening influences on original projection. According, it puts forward a kind of new beam-hardening correction method based on the basis images and TV model. Firstly, according to physical characteristics of the beam hardening an preliminary correction model with adjustable parameters is set up. Secondly, using different parameters, original projections are operated by the correction model. Thirdly, the projections are reconstructed to obtain a series of basis images. Finally, the linear combination of basis images is the final reconstruction image. Here, with total variation for the final reconstruction image as the cost function, the linear combination coefficients for the basis images are determined according to iterative method. To verify the effectiveness of the proposed method, the experiments are carried out on real phantom and industrial part. The results show that the algorithm significantly inhibits cup and strip artifacts in CT image. (authors)

Electromagnetic radiation reaction force and radiation potential in general five-dimensional relativity

International Nuclear Information System (INIS)

Lo, C.Y.; Goldstein, G.R.; Napier, A.

1989-01-01

A unified theory of electromagnetic and gravitational fields should modify classical electrodynamics to account for the radiation reaction force. A conjecture that the radiation reaction force and the Lorentz force should be distinct, but in unified forms, results in a five-dimensional unified theory of five variables. It is found that a semicylindrical condition can reconcile the apparent differences between a five-dimensional physical space and our four-dimensional perceptions. Analysis of the geodesic equations results in the notion of gauge dynamics which manifests the influence of the unrestricted fifth variable. The element g 55 of the five-dimensional metric is identified as the radiation potential, which can directly determine the radiation reaction force. This gives a distinct physical origin for the radiation process in classical theory. The potential suggests that the electron can have excited states in quantum electrodynamics. This theory is supported with calculations which demonstrate that the motion of the fifth variable directly causes physical changes in the four-dimensional subspace

Applications of the absolute reaction rate theory to biological responses in electric and magnetic fields

International Nuclear Information System (INIS)

Brannen, J.P.; Wayland, J.R.

1976-01-01

This paper develops a theoretical foundation for the study of biological responses of electric and magnetic fields. The basis of the development is the absolute reaction rate theory and the effects of fields on reaction rates. A simple application to the response of Bacillus subtilis var niger in a microwave field is made. Potential areas of application are discussed

Chemical reaction networks as a model to describe UVC- and radiolytically-induced reactions of simple compounds.

Science.gov (United States)

Dondi, Daniele; Merli, Daniele; Albini, Angelo; Zeffiro, Alberto; Serpone, Nick

2012-05-01

When a chemical system is submitted to high energy sources (UV, ionizing radiation, plasma sparks, etc.), as is expected to be the case of prebiotic chemistry studies, a plethora of reactive intermediates could form. If oxygen is present in excess, carbon dioxide and water are the major products. More interesting is the case of reducing conditions where synthetic pathways are also possible. This article examines the theoretical modeling of such systems with random-generated chemical networks. Four types of random-generated chemical networks were considered that originated from a combination of two connection topologies (viz., Poisson and scale-free) with reversible and irreversible chemical reactions. The results were analyzed taking into account the number of the most abundant products required for reaching 50% of the total number of moles of compounds at equilibrium, as this may be related to an actual problem of complex mixture analysis. The model accounts for multi-component reaction systems with no a priori knowledge of reacting species and the intermediates involved if system components are sufficiently interconnected. The approach taken is relevant to an earlier study on reactions that may have occurred in prebiotic systems where only a few compounds were detected. A validation of the model was attained on the basis of results of UVC and radiolytic reactions of prebiotic mixtures of low molecular weight compounds likely present on the primeval Earth.

Overview of physics results from MAST

NARCIS (Netherlands)

Lloyd, B.; Akers, R. J.; Alladio, F.; Allan, S.; Appel, L. C.; Barnes, M.; Barratt, N. C.; N. Ben Ayed,; Breizman, B. N.; Cecconello, M.; Challis, C. D.; Chapman, I.T.; Ciric, D.; Colyer, G.; Connor, J. W.; Conway, N. J.; Cox, M.; Cowley, S. C.; Cunningham, G.; Darke, A.; De Bock, M.; Delchambre, E.; De Temmerman, G.; Dendy, R. O.; Denner, P.; Driscoll, M. D.; Dudson, B.; Dunai, D.; Dunstan, M.; Elmore, S.; Field, A. R.; Fishpool, G.; Freethy, S.; Garzotti, L.; Gibson, K. J.; Gryaznevich, M. P.; Guttenfelder, W.; Harrison, J.; Hastie, R. J.; Hawkes, N. C.; Hender, T. C.; Hnat, B.; Howell, D. F.; Hua, M. D.; Hubbard, A.; Huysmans, G.; Keeling, D.; Kim, Y. C.; Kirk, A.; Liang, Y.; Lilley, M. K.; Lisak, M.; Lisgo, S.; Liu, Y. Q.; Maddison, G. P.; Maingi, R.; Manhood, S. J.; Martin, R.; McArdle, G. J.; McCone, J.; Meyer, H.; Michael, C.; Mordijck, S.; Morgan, T.; Morris, A. W.; Muir, D. G.; Nardon, E.; Naylor, G.; O' Brien, M. R.; O' Gorman, T.; Palenik, J.; Patel, A.; Pinches, S. D.; Price, M. N.; Roach, C. M.; Rozhansky, V.; Saarelma, S.; Sabbagh, S. A.; Saveliev, A.; Scannell, R.; Sharapov, S. E.; Shevchenko, V.; Shibaev, S.; Stork, D.; Storrs, J.; Suttrop, W.; Sykes, A.; Tamain, P.; Taylor, D.; Temple, D.; Thomas-Davies, N.; Thornton, A.; Turnyanskiy, M. R.; Valovic, M.; Vann, R. G. L.; Voss, G.; Walsh, M. J.; Warder, S. E. V.; Wilson, H. R.; Windridge, M.; Wisse, M.; Zoletnik, S.

2011-01-01

Major developments on the Mega Amp Spherical Tokamak (MAST) have enabled important advances in support of ITER and the physics basis of a spherical tokamak (ST) based component test facility (CTF), as well as providing new insight into underlying tokamak physics. For example, L-H transition studies

Physical education of students from sports-oriented technologies

Directory of Open Access Journals (Sweden)

U.A. Dolinnyj

2013-10-01

Full Text Available In theory grounded and experimentally tested the efficiency of employments on physical education of students on the basis of sporting oriented technologies. In experiment participated 30 students of 3 courses. The improvement of growth of most physical indexes rate is marked: speed qualities (at run on 100 m, power (bending, unbending of hands in support lying, speed-power (broad jump from a place, flexibility (inclination in before from position sitting on the floor. Recommendations are resulted on education of student youth a sense of collectivism; to the persistence, decision, purposefulness; attention and speed of thought; perfections of ability to manage the emotions, to development of physical qualities. It is proved that physical education of students on the basis of sporting oriented technologies positively influences on development of physical qualities, skills and abilities that is necessary for the future specialist.

Physical and biological basis of hadron radiotherapy. Book of abstracts

International Nuclear Information System (INIS)

2011-09-01

The Workshop was a satellite event of the 14 th International Congress of Radiation Research (ICRR-2011). It was held in Cracow, Poland, on the 2 and 3 September 2011, at the Collegium Novum of the Jagiellonian University. The Workshop organized, jointly by the Institute of Nuclear Physics of the Polish Academy of Sciences and the Polish Radiation Research Society, would provide its participants with an opportunity to discuss current topics in proton and carbon radiotherapy, clinical aspects of ion radiotherapy, ion beam dosimetry, unwanted patient exposure, radiobiology for ion radiotherapy and other relevant subjects. Book of Abstracts contains abstracts of 33 oral presentations and 12 posters.

Procedure for taking physical inventories

International Nuclear Information System (INIS)

Boston, R.A.

1984-01-01

Physical inventories are taken periodically to meet Company, State and IAEA requirements. Those physical inventories may be verified by IAEA and/or State inspectors. This presentation describes in an introductory but detailed manner the approaches and procedures used in planning, preparing, conducting, reconciling and reporting physical inventories for the Model Plant. Physical inventories are taken for plant accounting purposes to provide an accurate basis for starting and closing the plant material balance. Physical inventories are also taken for safeguards purposes to provide positive assurance that the nuclear materials of concern are indeed present and accounted for

(e,2e) reactions on atoms and molecules

International Nuclear Information System (INIS)

McCarthy, I.E.

1984-01-01

At high enough incident energy and for high enough momentum transfer an incident electron interacts with a single electron of a target atom or molecule, cleanly removing it and leaving the residual ion in one of its spectrum of quantum states. Under these conditions the dynamics of the reaction simply involves a two-electron collision, the target electron having a momentum given by the structure of the target and ion, and equal and opposite to the recoil momentum of the ion. Since two-electron collisions are well understood (Mott scattering) the reaction is the basis of the understanding of the energy and momentum structure of the target and ion known as electron momentum spectroscopy

Theoretical study of the Diels-Alder reaction between o-benzoquinone and norbornadiene

Science.gov (United States)

Quijano-Quiñones, Ramiro F.; Quesadas-Rojas, M.; Cuevas, Gabriel; Mena-Rejón, Gonzalo J.

2013-06-01

The reaction between norbornadiene and o-benzoquinone is an important step in polyalicyclic rigid structures synthesis. It has been considered that this reaction is an example of Diels-Alder (DA) and hetero-Diels-Alder (HDA) cycloadditions with o-benzoquinone acting as diene (forming C-C bonds) and heterodiene (forming O-C bonds). We have performed a Density Functional Theory study of this reaction, employing B3LYP, mPW1PW91, and B1B95 functionals and 6-31G(d,p) and 6-31+G(d,p) Gaussian type basis sets. The results indicate that Diels-Alder is a feasible mechanism for both reactions, but should not be the main route to the formation of products with C-C bonds.

Theoretical study of the Diels-Alder reaction between o-benzoquinone and norbornadiene

International Nuclear Information System (INIS)

Quijano-Quiñones, Ramiro F; Quesadas-Rojas, M; Mena-Rejón, Gonzalo J; Cuevas, Gabriel

2013-01-01

The reaction between norbornadiene and o-benzoquinone is an important step in polyalicyclic rigid structures synthesis. It has been considered that this reaction is an example of Diels-Alder (DA) and hetero-Diels-Alder (HDA) cycloadditions with o-benzoquinone acting as diene (forming C-C bonds) and heterodiene (forming O-C bonds). We have performed a Density Functional Theory study of this reaction, employing B3LYP, mPW1PW91, and B1B95 functionals and 6-31G(d,p) and 6-31+G(d,p) Gaussian type basis sets. The results indicate that Diels-Alder is a feasible mechanism for both reactions, but should not be the main route to the formation of products with C-C bonds.

Soft matter physics

CERN Document Server

Doi, Masao

2013-01-01

Soft matter (polymers, colloids, surfactants and liquid crystals) are an important class of materials in modern technology. They also form the basis of many future technologies, for example in medical and environmental applications. Soft matter shows complex behaviour between fluids and solids, and used to be a synonym of complex materials. Due to the developments of the past two decades, soft condensed matter can now be discussed on the same sound physical basis as solid condensedmatter. The purpose of this book is to provide an overview of soft matter for undergraduate and graduate students

Computed Potential Energy Surfaces and Minimum Energy Pathway for Chemical Reactions

Science.gov (United States)

Walch, Stephen P.; Langhoff, S. R. (Technical Monitor)

1994-01-01

Computed potential energy surfaces are often required for computation of such observables as rate constants as a function of temperature, product branching ratios, and other detailed properties. We have found that computation of the stationary points/reaction pathways using CASSCF/derivative methods, followed by use of the internally contracted CI method with the Dunning correlation consistent basis sets to obtain accurate energetics, gives useful results for a number of chemically important systems. Applications to complex reactions leading to NO and soot formation in hydrocarbon combustion are discussed.

Research in theoretical nuclear physics. Final report, April 1, 1993 - March 31, 1996

International Nuclear Information System (INIS)

Udagawa, Takeshi

1997-08-01

This report describes the accomplishments in basic research in nuclear physics carried out by the theoretical nuclear physics group in the Department of Physics at the University of Texas at Austin, during the period of April 1, 1993 to March 31, 1996. The work done covers three separate areas, low energy nuclear reactions, intermediate energy physics, and nuclear structure studies. Although the various subjects are spread among different areas, they are all based on two techniques that they have developed in previous years. These techniques are: (a) a powerful method for continuum-random-phase-approximation (CRPA) calculations of the nuclear response; and, (b) the direct reaction approach to complete and incomplete fusion reactions, which enables them to describe on a single footing all the different types of nuclear reactions, i.e., complete fusion, incomplete fusion and direct reactions, in a systematic way based on a single theoretical framework. In this report, the authors first summarize their achievements in these three areas, and then present final remarks

Diets formulated on total or digestible amino acid basis with different energy levels and physical form on broiler performance

Directory of Open Access Journals (Sweden)

A Maiorka

2005-03-01

Full Text Available We studied the effects of two different systems of expressing amino acid requirements (total - TAA or digestible - DAA, two energy levels (2,900 or 3,200 kcal of ME/kg and two physical forms (mash or pellet on the performance of male broilers from 21 to 42 d of age. Diets formulated on DAA basis improved feed conversion (p<0.001 and the conversion of consumed ME into body weight gain (p<0.001. Birds fed 3,200 kcal ME/kg presented better feed conversion (p<0.001, higher abdominal fat deposition (p<0.001 and worse conversion of consumed ME into body weight gain (p<0.001 as compared to birds fed 2,900 kcal ME/kg. Birds fed pelleted feed had higher feed intake (p<0.001, higher weight gain (p<0.001, better feed conversion (p<0.001, better conversion of consumed ME into body weight gain (p<0.001 and higher abdominal fat deposition (p<0.001. The results obtained in the present study suggest that feed formulation based on DAA is required when diets contain protein sources which amino acid digestibility is unreliable. Besides, pelleted feed improves performance parameters of broilers.

Basis for calculations in the topological expansion

International Nuclear Information System (INIS)

Levinson, M.A.

1982-12-01

Investigations aimed at putting the topological theory of particles on a more quantitative basis are described. First, the incorporation of spin into the topological structure is discussed and shown to successfully reproduce the observed lowest mass hadron spectrum. The absence of parity-doubled states represents a significant improvement over previous efforts in similar directions. This theory is applied to the lowest order calculation of elementary hadron coupling constant ratios. SU(6)/sub W/ symmetry is maintained and extended via the notions of topological supersymmetry and universality. Finally, efforts to discover a perturbative basis for the topological expansion are described. This has led to the formulation of off-shell Feynman-like rules which provide a calculational scheme for the strong interaction components of the topological expansion once the zero-entropy connected parts are known. These rules are shown to imply a topological asymptotic freedom. Even though the nonlinear zero-entropy problem cannot itself be treated perturbatively, plausible general assumptions about zero-entropy amplitudes allow immediate qualitative inferences concerning physical hadrons. In particular, scenarios for mass splittings beyond the supersymmetric level are described

TRIMOLECULAR REACTIONS OF URANIUM HEXAFLUORIDE WITH WATER

Energy Technology Data Exchange (ETDEWEB)

Westbrook, M.; Becnel, J.; Garrison, S.

2010-02-25

The hydrolysis reaction of uranium hexafluoride (UF{sub 6}) is a key step in the synthesis of uranium dioxide (UO{sub 2}) powder for nuclear fuels. Mechanisms for the hydrolysis reactions are studied here with density functional theory and the Stuttgart small-core scalar relativistic pseudopotential and associated basis set for uranium. The reaction of a single UF{sub 6} molecule with a water molecule in the gas phase has been previously predicted to proceed over a relatively sizeable barrier of 78.2 kJ {center_dot} mol{sup -1}, indicating this reaction is only feasible at elevated temperatures. Given the observed formation of a second morphology for the UO{sub 2} product coupled with the observations of rapid, spontaneous hydrolysis at ambient conditions, an alternate reaction pathway must exist. In the present work, two trimolecular hydrolysis mechanisms are studied with density functional theory: (1) the reaction between two UF{sub 6} molecules and one water molecule, and (2) the reaction of two water molecules with a single UF{sub 6} molecule. The predicted reaction of two UF{sub 6} molecules with one water molecule displays an interesting 'fluorine-shuttle' mechanism, a significant energy barrier of 69.0 kJ {center_dot} mol{sup -1} to the formation of UF{sub 5}OH, and an enthalpy of reaction ({Delta}H{sub 298}) of +17.9 kJ {center_dot} mol{sup -1}. The reaction of a single UF{sub 6} molecule with two water molecules displays a 'proton-shuttle' mechanism, and is more favorable, having a slightly lower computed energy barrier of 58.9 kJ {center_dot} mol{sup -1} and an exothermic enthalpy of reaction ({Delta}H{sub 298}) of -13.9 kJ {center_dot} mol{sup -1}. The exothermic nature of the overall UF{sub 6} + 2 {center_dot} H{sub 2}O trimolecular reaction and the lowering of the barrier height with respect to the bimolecular reaction are encouraging; however, the sizable energy barrier indicates further study of the UF{sub 6} hydrolysis reaction

Solid state physics for metallurgists

CERN Document Server

Weiss, Richard J

2013-01-01

Metal Physics and Physical Metallurgy, Volume 6: Solid State Physics for Metallurgists provides an introduction to the basic understanding of the properties that make materials useful to mankind. This book discusses the electronic structure of matter, which is the domain of solid state physics.Organized into 12 chapters, this volume begins with an overview of the electronic structure of free atoms and the electronic structure of solids. This text then examines the basis of the Bloch theorem, which is the exact periodicity of the potential. Other chapters consider the fundamental assumption in

Physical Attractiveness, Age, and Sex as Determinants of Reactions to Resumes.

Science.gov (United States)

Quereshi, M. Y.; Kay, Janet P.

1986-01-01

Physical attractiveness, age, and sex were manipulated to determine their effect on the evaluation of 54 hypothetical applicants' resumes for three different jobs by 60 Master's in Business Administration students. Physical attractiveness favorably influenced the suitability ratings for all jobs; raters' sex and age were not significant but…

Physics Division annual review, 1 April 1982-31 March 1983

International Nuclear Information System (INIS)

Gemmell, D.S.

1983-06-01

Nuclear, atomic, and molecular physics research activities at ANL are described. Progress summaries are given under general headings: medium-energy physics research (nuclear structure, two-nucleon physics with pions and electrons, weak interactions, particle searches, measurement of the electric dipole moment of the neutron, and GeV electron microtron); research at the tandem and superconducting linac (high angular momentum states in nuclei, fusion of heavy ions, reaction mechanisms and distribution of reaction strengths, accelerator mass spectrometry, selected nuclear spectroscopy at the tandem-linac, and equipment development at the tandem-linac facility); theoretical nuclear physics (nuclear forces and subnucleon degrees of freedom, variational calculations of finite many-body systems, nuclear shell theory and nuclear structure, intermediate energy physics, and heavy-ion reactions); the superconducting linac; accelerator operations (tandem-linac and the Dynamitron facility); and data acquisition and analysis systems. Atomic and molecular physics research is reported under the following broad headings: photoionization-photoelectron research, high-resolution laser-rf spectroscopy, beam-foil research and collision dynamics of heavy ions, interactions of fast atomic and molecular ions with solid and gaseous targets, theoretical atomic physics, and electron spectroscopy with fast atomic and molecular-ion beams. Publications are listed

[Experimental and theoretical nuclear physics]: 1988 Annual report

International Nuclear Information System (INIS)

1988-05-01

This paper describes the highlights of the past year of the Nuclear Physics Laboratory at the University of Washington. Particular topics discussed are: astrophysics, giant resonance, heavy ion induced reactions, fundamental symmetries, nuclear reactions, medium energy reactions, accelerator mass spectrometry, Van de Graaf and ion sources, the booster linac project, instrumentation and computer systems

26 CFR 1.1014-4 - Uniformity of basis; adjustment to basis.

Science.gov (United States)

2010-04-01

...) INCOME TAX (CONTINUED) INCOME TAXES Basis Rules of General Application § 1.1014-4 Uniformity of basis... to property acquired by bequest, devise, or inheritance relate back to the death of the decedent... prescribing a general uniform basis rule for property acquired from a decedent is, on the one hand, to tax the...

Nuclear physics and fundamental physics explored with neutrons

International Nuclear Information System (INIS)

Masuda, Yasuhiro

1995-08-01

This Japan Hadron Project workshop was held on May 19 and 20, 1995, at Institute for Nuclear Study, University of Tokyo. The Neutron Arena planned in JHP is the facility that uses the spallation neutrons generated by high energy protons, and its utilization is planned in wide research fields. On the other hand, in the neutron scattering facility in the booster utilization facility of National Laboratory for High Energy Physics, the researches of verifying parity nonconservation and time reversal break have been carried out so far. It is necessary to accurately measure the reaction cross section of neutrons in low energy region. This workshop was planned for examining the Neutron Arena by the researchers related to elementary particles and atomic nuclei. In the workshop, lectures were given on the break of the reversal symmetry of time and space in neutron-atomic nucleus reaction, neutrino physics, neutron capture and celestial nuclear physics, neutron-induced nucleosynthesis, development and utilization of very cold neutron interferometer using multi-layer film mirror, research on gravity using neutron interferometer, electric polarizability of neutrons, β decay of neutrons, possibility of research on basic symmetry problem at E-arena, β decay in storage ring, neutron electric dipole moment using ultracold neutrons, magnetic confinement and control of ultracold neutrons, and outline of JHP neutron source. (K.I.)

Back reaction of excitations on a vortex

International Nuclear Information System (INIS)

Arodz, H.; Hadasz, L.

1997-01-01

Excitations of a vortex are usually considered in a linear approximation neglecting their back reaction on the vortex. In the present paper we investigate back reaction of Proca-type excitations on a straight linear vortex in the Abelian Higgs model. We propose an exact ansatz for fields of the excited vortex. From an initial set of six nonlinear field equations we obtain (in a limit of weak excitations) two linear wave equations for the back reaction corrections. Their approximate solutions are found in the cases of plane wave and wave-packet-type excitations. We find that the excited vortex radiates the vector field and that the Higgs field has a very broad oscillating component. copyright 1997 The American Physical Society

BOOK REVIEW: The Physical Basis of the Direction of Time

Science.gov (United States)

Giulini, Domenico

2008-10-01

This is the fifth edition of H Dieter Zeh's classic text on the physical foundations of time-irreversibility in the phenomena. A forerunner of this book was the 1984 German text 'Die Physik der Zeitrichtung' of about 80 pages, which appeared as volume 200 in the Springer series Lecture Notes in Physics. It was soon followed by a largely revised and extended English edition of about twice the length. Since then each new edition has been thoroughly revised and, edition by edition, new topics and chapters have been added. As the author says in the introduction: 'The prime intention of this book is to discuss the relations between various arrows of time, and to search for a universal master arrow'. Correspondingly, after a short chapter on 'the physical concept of time', the author systematically discusses in the remaining five chapters the time arrows in electromagnetic radiation theory, in thermodynamics, in quantum mechanics, in black-hole physics and cosmology, and in quantum cosmology. The chapters on thermodynamics and quantum mechanics slightly outweigh the others in terms of length. The fifth edition now includes two new section on 'cosmic probabilities and history' and 'quantum computers', and the section on the 'expansion of the universe' has been restructured and extended. Other changes concentrate on the sections on radiation damping, decoherence, interpretation of quantum theory, and quantum cosmology. It should also be mentioned that the author maintains a regularly updated website for the book at www.time-direction.de. The reading is always highly stimulating and uses results and ideas from a very broad range of physics, with interspersed historical and philosophical comments. Somehow outstanding and of particular interest is the chapter on quantum cosmology, which raises novel interpretational issues that cannot be found in any other textbook I know of on time asymmetry. As regards the mathematical prerequisites, the reader is assumed to have some

Biophysical basis of low-power-laser effects

Science.gov (United States)

Karu, Tiina I.

1996-06-01

Biological responses of cells to visible and near IR (laser) radiation occur due to physical and/or chemical changes in photoacceptor molecules, components of respiratory chains (cyt a/a3 in mitochondria). As a result of the photoexcitation of electronic states, the following physical and/or chemical changes can occur: alteration of redox properties and acceleration of electron transfer, changes in biochemical activity due to local transient heating of chromophores, one-electron auto-oxidation and O2- production, and photodynamic action and 1O2 production. Different reaction channels can be activated to achieve the photobiological macroeffect. The primary physical and/or chemical changes induced by light in photoacceptor molecules are followed by a cascade of biochemical reactions in the cell that do not need further light activation and occur in the dark (photosignal transduction and amplification chains). These actions are connected with changes in cellular homeostasis parameters. The crucial step here is thought to be an alteration of the cellular redox state: a shift towards oxidation is associated with stimulation of cellular vitality, and a shift towards reduction is linked to inhibition. Cells with a lower than normal pH, where the redox state is shifted in the reduced direction, are considered to be more sensitive to the stimulative action of light than those with the respective parameters being optimal or near optimal. This circumstance explains the possible variations in observed magnitudes of low-power laser effects. Light action on the redox state of a cell via the respiratory chain also explains the diversity of low-power laser effects. Beside explaining many controversies in the field of low-power laser effects (i.e., the diversity of effects, the variable magnitude or absence of effects in certain studies), the proposed redox-regulation mechanism may be a fundamental explanation for some clinical effects of irradiation, for example the positive

From simple to complex and backwards. Chemical reactions under very high pressure

International Nuclear Information System (INIS)

Bini, Roberto; Ceppatelli, Matteo; Citroni, Margherita; Schettino, Vincenzo

2012-01-01

Highlights: ► High pressure reactivity of several molecular systems. ► Reaction kinetics and dynamics in high density conditions. ► Key role of optical pumping and electronic excitation. ► Perspectives for the synthesis of hydrogen. - Abstract: High pressure chemical reactions of molecular systems are discussed considering the various factors that can affect the reactivity. These include steric hindrance and geometrical constraints in the confined environment of crystals at high pressure, changes of the free energy landscape with pressure, photoactivation by two-photon absorption, local and collective effects. A classification of the chemical reactions at high pressure is attempted on the basis of the prevailing factors.

Investigations in atomic physics by heavy ion projectiles

International Nuclear Information System (INIS)

Berenyi, D.

1983-01-01

The utilization of heavy ion reactions in atomic physics is surveyed. The basic collision mechanisms and their consequences in atomic physics are summarized. The atomic and electronic processes during and after heavy ion collisions are reviewed as functions of the projectile energy. The main detection and measuring methods are described. Reviews of new information about the structure of electronic cloud and about fundamental processes based on the analysis of heavy ion reaction data are given. (D.Gy.)

Systematic trends in photonic reagent induced reactions in a homologous chemical family.

Science.gov (United States)

Tibbetts, Katharine Moore; Xing, Xi; Rabitz, Herschel

2013-08-29

The growing use of ultrafast laser pulses to induce chemical reactions prompts consideration of these pulses as "photonic reagents" in analogy to chemical reagents. This work explores the prospect that photonic reagents may affect systematic trends in dissociative ionization reactions of a homologous family of halomethanes, much as systematic outcomes are often observed for reactions between homologous families of chemical reagents and chemical substrates. The experiments in this work with photonic reagents of varying pulse energy and linear spectral chirp reveal systematic correlations between observable ion yields and the following set of natural variables describing the substrate molecules: the ionization energy of the parent molecule, the appearance energy of each fragment ion, and the relative strength of carbon-halogen bonds in molecules containing two different halogens. The results suggest that reactions induced by photonic reagents exhibit systematic behavior analogous to that observed in reactions driven by chemical reagents, which provides a basis to consider empirical "rules" for predicting the outcomes of photonic reagent induced reactions.

Electromagnetic Basis of Metabolism and Heredity

Science.gov (United States)

Freund, Friedemann; Stolc, Viktor

2016-01-01

Living organisms control their cellular biological clocks to maintain functional oscillation of the redox cycle, also called the "metabolic cycle" or "respiratory cycle". Organization of cellular processes requires parallel processing on a synchronized time-base. These clocks coordinate the timing of all biochemical processes in the cell, including energy production, DNA replication, and RNA transcription. When this universal time keeping function is perturbed by exogenous induction of reactive oxygen species (ROS), the rate of metabolism changes. This causes oxidative stress, aging and mutations. Therefore, good temporal coordination of the redox cycle not only actively prevents chemical conflict between the reductive and oxidative partial reactions; it also maintains genome integrity and lifespan. Moreover, this universal biochemical rhythm can be disrupted by ROS induction in vivo. This in turn can be achieved by blocking the electron transport chain either endogenously or exogenously by various metabolites, e.g. hydrogen sulfide (H2S), highly diffusible drugs, and carbon monoxide (CO). Alternatively, the electron transport in vivo can be attenuated via a coherent or interfering transfer of energy from exogenous ultralow frequency (ULF) and extremely low frequency (ELF) electromagnetic (EM) fields, suggesting that-on Earth-such ambient fields are an omnipresent (and probably crucially important) factor for the time-setting basis of universal biochemical reactions in living cells. Our work demonstrated previously un-described evidence for quantum effects in biology by electromagnetic coupling below thermal noise at the universal electron transport chain (ETC) in vivo.

Department of Nuclear Reactions: Overview

International Nuclear Information System (INIS)

Rusek, K.

1999-01-01

Full text: The Department of Nuclear Reactions had a very productive year. The following reports cover three major domains of our activities: nuclear, material and atomic physics. One of the current questions in modern nuclear physics is question of the phase transitions in nuclear matter. Our physicists, the members of the ALADIN Collaboration at Gesellschaft fuer Schwerionenforschung, participated in new experiments exploring properties of highly excited nuclear matter and the phenomenon of the liquid - gas phase transition. The experiments yielded a number of important results. Details can be found in the three short reports presented in this volume. Structure of a nucleon is another important subject of nuclear science research. In the last year energy region of Δ resonance has been investigated by means of charge exchange reaction. The experiment was performed at Laboratory National Saturne in Saclay by SPESIV-π collaboration consisting of physicist from Institute of Nuclear Physics Orsay, Niels Bohr Institute Copenhagen and from our Department. The main achievement of the experiment was evidence for a Δ - hole attraction in the spin longitudinal channel. Reactions induced by radioactive ion beams such as 6 He recently attract a lot of interest. There exist some evidences that the 6 He nucleus has a two-neutron halo structure similar to that well established for 11 Li. An analysis of 6 He + 4 He scattering data reported in this volume revealed some similarities between the loosely bound 6 Li nucleus and the neutron rich 6 He. Research in material physics has focused on two basic topics: a crystallographic model of uranium dioxide, a material currently used as a nuclear fuel and transformations of defects in GaAs crystals at low temperature. The investigations have been carried out in a wide collaboration with scientists from the University of Jena, Research Center Karlsruhe and Centre de Spectrometrie Nucleaire Orsay. Some experiments have been performed at

Progress report 1986-1987 Department of Physics

International Nuclear Information System (INIS)

1988-01-01

This progress report 1986-1987 deals with the first two years operation of the TANDAR electrostatic accelerator and also describes the research work in the following fields: nuclear physics (nuclear structure, nuclear reactions, intermediate energies, applied nuclear physics); solid state physics (crystallography and phase transitions, Mossbauer spectroscopy, condensed matter theory, crystals growth, instrumentation); atomic physics and computational physics. Finally, the staff, a list of publications and activities related to international agencies is included [es

Health physics

International Nuclear Information System (INIS)

Poston, J.W.

1974-01-01

In a series of eight lectures the following topics are dealt with: 1) interaction of radiation with matter; 2) radiation quantities and units; 3) the physical basis of radiation dosimetry; 4) detection and measurement of radiation; 5) mixed radiation dosimetry; 6) special methods in radiation dosimetry; 7) dose from electrons and beta rays; and 8) introduction to radiation biology

Insights into the mechanisms on chemical reactions: reaction paths for chemical reactions

International Nuclear Information System (INIS)

Dunning, T.H. Jr.; Rosen, E.; Eades, R.A.

1987-01-01

We report reaction paths for two prototypical chemical reactions: Li + HF, an electron transfer reaction, and OH + H 2 , an abstraction reaction. In the first reaction we consider the connection between the energetic terms in the reaction path Hamiltonian and the electronic changes which occur upon reaction. In the second reaction we consider the treatment of vibrational effects in chemical reactions in the reaction path formalism. 30 refs., 9 figs

Randomness in multi-step direct reactions

International Nuclear Information System (INIS)

Koning, A.J.; Akkermans, J.M.

1991-01-01

The authors propose a quantum-statistical framework that provides an integrated perspective on the differences and similarities between the many current models for multi-step direct reactions in the continuum. It is argued that to obtain a statistical theory two physically different approaches are conceivable to postulate randomness, respectively called leading-particle statistics and residual-system statistics. They present a new leading-particle statistics theory for multi-step direct reactions. It is shown that the model of Feshbach et al. can be derived as a simplification of this theory and thus can be founded solely upon leading-particle statistics. The models developed by Tamura et al. and Nishioka et al. are based upon residual-system statistics and hence fall into a physically different class of multi-step direct theories, although the resulting cross-section formulae for the important first step are shown to be the same. The widely used semi-classical models such as the generalized exciton model can be interpreted as further phenomenological simplification of the leading-particle statistics theory

New Insights into the Diels-Alder Reaction of Graphene Oxide.

Science.gov (United States)

Brisebois, Patrick P; Kuss, Christian; Schougaard, Steen B; Izquierdo, Ricardo; Siaj, Mohamed

2016-04-18

Graphene oxide is regarded as a major precursor for graphene-based materials. The development of graphene oxide based derivatives with new functionalities requires a thorough understanding of its chemical reactivity, especially for canonical synthetic methods such as the Diels-Alder cycloaddition. The Diels-Alder reaction has been successfully extended with graphene oxide as a source of diene by using maleic anhydride as a dienophile, thereby outlining the presence of the cis diene present in the graphene oxide framework. This reaction provides fundamental information for understanding the exact structure and chemical nature of graphene oxide. On the basis of high-resolution (13) C-SS NMR spectra, we show evidence for the formation of new sp(3) carbon centers covalently bonded to graphene oxide following hydrolysis of the reaction product. DFT calculations are also used to show that the presence of a cis dihydroxyl and C vacancy on the surface of graphene oxide are promoting the reaction with significant negative reaction enthalpies. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Attributions of responsibility and affective reactions to decision outcomes.

Science.gov (United States)

Zeelenberg, M; van der Pligt, J; de Vries, N K

2000-06-01

Immediate affective reactions to outcomes are more intense following decisions to act than following decisions not to act. This finding holds for both positive and negative outcomes. We relate this "actor-effect" to attribution theory and argue that decision makers are seen as more responsible for outcomes when these are the result of a decision to act as compared to a decision not to act. Experiment 1 (N = 80) tests the main assumption underlying our reasoning and shows that affective reactions to decision outcomes are indeed more intense when the decision maker is seen as more responsible. Experiment 2 (N = 40) tests whether the actor effect can be predicted on the basis of differential attributions following action and inaction. Participants read vignettes in which active and passive actors obtained a positive or negative outcome. Action resulted in more intense affect than inaction, and positive outcomes resulted in more intense affect than negative outcomes. Experiment 2 further shows that responsibility attributions and affective reactions to outcomes are highly correlated; that is, more extreme affective reactions are associated with more internal attributions. We discuss the implications for research on post-decisional reactions.

State-Transition Structures in Physics and in Computation

Science.gov (United States)

Petri, C. A.

1982-12-01

In order to establish close connections between physical and computational processes, it is assumed that the concepts of “state” and of “transition” are acceptable both to physicists and to computer scientists, at least in an informal way. The aim of this paper is to propose formal definitions of state and transition elements on the basis of very low level physical concepts in such a way that (1) all physically possible computations can be described as embedded in physical processes; (2) the computational aspects of physical processes can be described on a well-defined level of abstraction; (3) the gulf between the continuous models of physics and the discrete models of computer science can be bridged by simple mathematical constructs which may be given a physical interpretation; (4) a combinatorial, nonstatistical definition of “information” can be given on low levels of abstraction which may serve as a basis to derive higher-level concepts of information, e.g., by a statistical or probabilistic approach. Conceivable practical consequences are discussed.

(p, α) reactions: knock-on(out) or pick-up

International Nuclear Information System (INIS)

Gadioli, E.

1983-01-01

Nothwithstanding the great lot of data collected starting from the beginning of fifties, it cannot be said that a good degree of knowledge about the (p, α) reaction mechanism has been reached. Experimental data are usually interpreted or on the basis of a pure pick-up or knock-on(out) mechanism, though many results suggest the importance of both mechanism

[Intermediate energy nuclear physics

International Nuclear Information System (INIS)

1989-01-01

This report summarizes work in experimental Intermediate Energy Nuclear Physics carried out between October 1, 1988 and October 1, 1989 at the Nuclear Physics Laboratory of the University of Colorado, Boulder, under grant DE-FG02-86ER-40269 with the United States Department of Energy. The experimental program is very broadly based, including pion-nucleon studies at TRIUMF, inelastic pion scattering and charge exchange reactions at LAMPF, and nucleon charge exchange at LAMPF/WNR. In addition, a number of other topics related to accelerator physics are described in this report

Safety Basis Report

International Nuclear Information System (INIS)

R.J. Garrett

2002-01-01

As part of the internal Integrated Safety Management Assessment verification process, it was determined that there was a lack of documentation that summarizes the safety basis of the current Yucca Mountain Project (YMP) site characterization activities. It was noted that a safety basis would make it possible to establish a technically justifiable graded approach to the implementation of the requirements identified in the Standards/Requirements Identification Document. The Standards/Requirements Identification Documents commit a facility to compliance with specific requirements and, together with the hazard baseline documentation, provide a technical basis for ensuring that the public and workers are protected. This Safety Basis Report has been developed to establish and document the safety basis of the current site characterization activities, establish and document the hazard baseline, and provide the technical basis for identifying structures, systems, and components (SSCs) that perform functions necessary to protect the public, the worker, and the environment from hazards unique to the YMP site characterization activities. This technical basis for identifying SSCs serves as a grading process for the implementation of programs such as Conduct of Operations (DOE Order 5480.19) and the Suspect/Counterfeit Items Program. In addition, this report provides a consolidated summary of the hazards analyses processes developed to support the design, construction, and operation of the YMP site characterization facilities and, therefore, provides a tool for evaluating the safety impacts of changes to the design and operation of the YMP site characterization activities

Safety Basis Report

Energy Technology Data Exchange (ETDEWEB)

R.J. Garrett

2002-01-14

As part of the internal Integrated Safety Management Assessment verification process, it was determined that there was a lack of documentation that summarizes the safety basis of the current Yucca Mountain Project (YMP) site characterization activities. It was noted that a safety basis would make it possible to establish a technically justifiable graded approach to the implementation of the requirements identified in the Standards/Requirements Identification Document. The Standards/Requirements Identification Documents commit a facility to compliance with specific requirements and, together with the hazard baseline documentation, provide a technical basis for ensuring that the public and workers are protected. This Safety Basis Report has been developed to establish and document the safety basis of the current site characterization activities, establish and document the hazard baseline, and provide the technical basis for identifying structures, systems, and components (SSCs) that perform functions necessary to protect the public, the worker, and the environment from hazards unique to the YMP site characterization activities. This technical basis for identifying SSCs serves as a grading process for the implementation of programs such as Conduct of Operations (DOE Order 5480.19) and the Suspect/Counterfeit Items Program. In addition, this report provides a consolidated summary of the hazards analyses processes developed to support the design, construction, and operation of the YMP site characterization facilities and, therefore, provides a tool for evaluating the safety impacts of changes to the design and operation of the YMP site characterization activities.

Department of Nuclear Reaction - Overview

International Nuclear Information System (INIS)

Budzanowski, A.

2000-01-01

Full text: This year 1999 can be considered as very successful. Not only that we have published 33 papers in journals listed by the Philadelphia Institute of Science but because our hard work allowed us to obtain new and exciting results. A group of theoretical papers concerned with application of correlation among random matrices elements developed for statistical aspects of nuclear coupling into continuum to study of the collective effects in brain activity and stock market dynamics. These papers arose quite an interest and got several citations. Studies of the nonpartonic components in the nucleon structure function led to better understanding of the higher-twist effects. It was shown that inclusion of the terms of the order of 1/Q 4 improves fits to the experimental data. A review paper summarizing results on the role of the leading baryon in high energy reactions appeared in Progress on Nuclear and Particle Physics. Studies on multistep transfer reactions of light heavy ions in collaboration with the Institute of Nuclear Physics of the Ukrainian Academy of Sciences in Kiev have explained angular distributions of many reactions using the coupled channel theory. We have shown that it is possible to determine energy dependence of the optical model potential for such unstable nuclei like 8 Be. Further studies of mechanism of near threshold light meson production in collaboration with Juelich and Jagiellonian University were performed. Within COSY 10 and COSY 11 collaborations new data on the isospin symmetry breaking in pionic reactions and strange meson accompanied by hyperons emission were obtained. Together with colleagues from the Flerov Nuclear Reaction Laboratory we have started experiments with radioactive beams. Using magnetic separator COMBAS velocity distributions of isotopes with 2 ≤Z≤11 in reactions induced by 16 O on 9 Be were obtained. At the high resolution radioactive beam channel ACCULINA reactions induced by 6 He and 8 He nuclei were studied

Physics with primary beams of the KEK-PS

International Nuclear Information System (INIS)

Tanaka, Kazuhiro; Yoshii, Masahito

1993-08-01

The 12-GeV Proton Synchrotron (PS) at the National Laboratory for High Energy Physics (KEK) has provided great opportunities to high-energy-physics and related communities as a unique high-energy hadron machine, since its operation in 1976. Activities of the KEK-PS are indispensable for the rapid development in the field. Six experimental subjects are proposed in this Report; (1) media effects in φ meson decay, (2) multifragmentation in high-energy reactions, (3) mechanism of high-energy reactions by means of radio-chemical methods, (4) physics with polarized high-energy neutrons, (5) physics with polarized high-energy deuterons, and (6) hypernucleus with high-energy heavy-ion beams. As a summary, new facilities (a new injector, a new beamline and a new experimental area) and physics programs with primary beams, proposed in this Report are themselves unique and valuable. Moreover, technical developments and physics outcomes stimulated with those new facilities are indispensable for future plans of the KEK-PS. (J.P.N.)

Forecasting report. Particle physics

International Nuclear Information System (INIS)

The present status of nuclear physics is examined. The various nuclear models, and theories for nuclear structure, nuclear reactions and nucleon-nucleon forces between free nucleons and nucleon inside nuclei are briefly presented. A new future towards exotic and superheavy nuclei is outlined, with nuclear macrophysics, and complex excitations. Nuclear physics connections with other fields and society are also examined and the tools of the physicists briefly surveyed [fr

Identification of Physical Parameters for A Hydraulic Robot

DEFF Research Database (Denmark)

Madsen, Henrik; Zhou, Jianjun; Hansen, Lars Henrik

1997-01-01

This paper describes a case study of identifying the physical model of a hydraulic test robot. The obtained model is intended to provide a basis for model-based control of the robot. The physical model is formulated in continuous time and is derived by application of the laws of physics...

Theoretical investigation of reactions between ammonia and precursors from the ozonolysis of ethene

Energy Technology Data Exchange (ETDEWEB)

Jorgensen, Solvejg, E-mail: solvejg@kemi.ku.dk [Copenhagen Center of Atmospheric Research, Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen O (Denmark); Gross, Allan, E-mail: agr@dmi.dk [Research Department, Danish Meteorological Institute, Lyngbyvej 100, DK-2100 Copenhagen O (Denmark)

2009-07-30

The reaction mechanisms between ammonia and two secondary organic aerosol (SOA) precursors from ozonolysis of alkenes - namely the secondary ozonide (SOZ) and hydroxyl substituted ester (HSE) have been investigated using quantum mechanics calculations. For the reaction between ammonia and SOZ, three reaction channels were found (i) an aldehyde, a hydrogen peroxide and an imine, (ii) two aldehydes and a hydroxylamine, (iii) a hydroxyalkyl hydroperoxide and an imine. For the reaction involving the HSE the reaction products are an aldehyde, carboxylic acid and ammonia. The B3LYP method with 6-311++G(2d,2p) basis set was employed for the geometry optimisation of the stationary points. Gaussian 2 and Gaussian 3 levels of theory have been used to optimise and refine the energy. From an energetic point of view, it is concluded that the reaction between ammonia and HSE is in favour compared to the one with the SOZ.

Improved techniques for outgoing wave variational principle calculations of converged state-to-state transition probabilities for chemical reactions

Science.gov (United States)

Mielke, Steven L.; Truhlar, Donald G.; Schwenke, David W.

1991-01-01

Improved techniques and well-optimized basis sets are presented for application of the outgoing wave variational principle to calculate converged quantum mechanical reaction probabilities. They are illustrated with calculations for the reactions D + H2 yields HD + H with total angular momentum J = 3 and F + H2 yields HF + H with J = 0 and 3. The optimization involves the choice of distortion potential, the grid for calculating half-integrated Green's functions, the placement, width, and number of primitive distributed Gaussians, and the computationally most efficient partition between dynamically adapted and primitive basis functions. Benchmark calculations with 224-1064 channels are presented.

[Experimental nuclear physics]. Annual report 1989

Energy Technology Data Exchange (ETDEWEB)

NONE

1989-04-01

This is the April 1989 annual report of the Nuclear Physics Labortaory of the University of Washington. It contains chapters on astrophysics, giant resonances, heavy ion induced reactions, fundamental symmetries, polarization in nuclear reactions, medium energy reactions, accelerator mass spectrometry (AMS), research by outside users, Van de Graaff and ion sources, computer systems, instrumentation, and the Laboratory`s booster linac work. An appendix lists Laboratory personnel, Ph.D. degrees granted in the 1988-1989 academic year, and publications. Refs., 23 figs., 3 tabs.

Reaction-Diffusion Automata Phenomenology, Localisations, Computation

CERN Document Server

Adamatzky, Andrew

2013-01-01

Reaction-diffusion and excitable media are amongst most intriguing substrates. Despite apparent simplicity of the physical processes involved the media exhibit a wide range of amazing patterns: from target and spiral waves to travelling localisations and stationary breathing patterns. These media are at the heart of most natural processes, including morphogenesis of living beings, geological formations, nervous and muscular activity, and socio-economic developments.   This book explores a minimalist paradigm of studying reaction-diffusion and excitable media using locally-connected networks of finite-state machines: cellular automata and automata on proximity graphs. Cellular automata are marvellous objects per se because they show us how to generate and manage complexity using very simple rules of dynamical transitions. When combined with the reaction-diffusion paradigm the cellular automata become an essential user-friendly tool for modelling natural systems and designing future and emergent computing arch...

Reactions of psychiatric patients to telepsychiatry

Directory of Open Access Journals (Sweden)

Robbie Campbell

2015-10-01

Full Text Available Telepsychiatry could offer a viable medical service to remote or isolated social communities if it does not generate adverse reactions such as delusional ideation, particularly in patients in settlements without adequate exposure to mainstream culture and internet. We examined subjective reactions to telepsychiatry of randomly selected 84 psychiatric patients from remote locations in Ontario, Canada. They rated the quality of their teleconferencing sessions via 10 item questionnaire and were asked about advantages and disadvantages of telepsychiatry. The majority of patients indicated that they were able to communicate as if physically present (92.9% and were comfortable with telepsychiatric service (95.2%. They found the sessions as beneficial as direct meetings with their psychiatrist (84.5% and would use this service again (98.8%. There were no instances of telepsychiatry being associated with adverse reactions in patients from remote communities with inadequate exposure to modern mainstream culture and internet.

Physical properties

International Nuclear Information System (INIS)

Anon.

1976-01-01

Research activities into the physical properties of metals and ceramics at Lawrence Berkeley Laboratory during 1976 are reported. Topics covered include: high field superconductivity; microstructure and mechanical behavior of ceramics, glass-metal, and ceramic-metal systems; high temperature reactions; relation of microstructure to properties in ceramics; and structure and properties of carbon materials and composite materials

Annual report on nuclear physics activities

International Nuclear Information System (INIS)

Beck, R.; Bueche, G.; Fluegge, G.

1982-02-01

This report surveys the activities in fundamental research from July 1, 1980 to June 30, 1981 at the three institutes of the KfK which are concerned with nuclear physics. The research program comprises laser spectroscopy, nuclear reactions with light ions and physics at medium and higher energies. (orig.) [de

Nuclear physics laboratory

International Nuclear Information System (INIS)

Deruytter, A.J.

1978-01-01

The report summarizes the main activities of the Linear Electron Accelerator Section of the Physics Laboratory of the State University of Ghent. The research fields are relative to: 1. Nuclear fission. 2. Photonuclear reactions. 3. Nuclear spectroscopy and positron annihilation. 4. Dosimetry. 5. Theoretical studies. (MDC)

Nuclear physics laboratory

International Nuclear Information System (INIS)

Deruytter, A.J.

1979-01-01

The report summarizes the main activities of the Linear Electron Accelerator Section of the Physics Laboratory of the State University of Ghent. The research fields are relative to: 1. Nuclear fission. 2. Photonuclear reactions. 3. Nuclear spectroscopy and positron annihilation. 4. Dosimetry. 5. Theoretical studies. (MDC)