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1

Enrico Fermi Achieves First Self Sustain Nuclear Chain Reaction...  

National Nuclear Security Administration (NNSA)

Self Sustain Nuclear Chain Reaction Chicago, IL Metallurgical Laboratory scientists led by Enrico Fermi achieve the first self-sustained nuclear chain reaction in pile...

2

Nuclear chain reaction: forty years later  

SciTech Connect

The proceedings from a 1982 symposium 40 years after the first controlled nuclear chain reaction took place in Chicago covers four sessions and public discussion. The session covered the history of the chain reaction; peaceful uses in technology, medicine, and biological science; peaceful uses in power generation; and nuclear weapons control. Among the speakers were Eugene Wigner, Glenn Seaborg, Alvin Weinberg, and others who participated in the first chain reaction experiments. The proceedings reflect differences of opinion among the scientists as well as the general public. References, slides, and tables used to illustrate the individual talks are included with the papers.

Sachs, R.G. (ed.)

1984-01-01T23:59:59.000Z

3

Enrico Fermi Achieves First Self Sustain Nuclear Chain Reaction | National  

National Nuclear Security Administration (NNSA)

Enrico Fermi Achieves First Self Sustain Nuclear Chain Reaction | National Enrico Fermi Achieves First Self Sustain Nuclear Chain Reaction | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog Home > About Us > Our History > NNSA Timeline > Enrico Fermi Achieves First Self Sustain Nuclear ... Enrico Fermi Achieves First Self Sustain Nuclear Chain Reaction

4

Enrico Fermi and the First Self-Sustaining Nuclear Chain Reaction  

Office of Scientific and Technical Information (OSTI)

the first self-sustaining chain reaction and thereby initiated the controlled release of nuclear energy." Fermi's momentous accomplishments caused him to be recognized as one of...

5

New Nuclear Reaction  

Science Journals Connector (OSTI)

Thermonuclear-like reaction points to possibilities for better kind of nuclear energy ... FISSION can make a chain reaction take place, as can fusion. ... To these two, scientists at University of California Radiation Laboratory have added a third: a "catalyzed nuclear reaction," a reaction that yields energy and is akin to fusion (thermonuclear) reactions. ...

1957-01-14T23:59:59.000Z

6

Nuclear reactions  

Science Journals Connector (OSTI)

Much reference has been made in the last chapter to nuclear energy levels and their various properties (e.g ... ways of doing this — the use of nuclear reactions, and studies of how excited nuclei...

R. J. Blin-Stoyle FRS

1991-01-01T23:59:59.000Z

7

Lesson 5- Fission and Chain Reactions  

Energy.gov (U.S. Department of Energy (DOE))

Lesson Four showed how the nuclei of atoms store energy and how unstable atoms decay and release energy. How do nuclear engineers use this knowledge to help them harness energy to make electricity? The answer lies in being able to start a nuclear chain reaction in fuel inside a nuclear power plant and keep it going. This lesson examines nuclear reactions called fission as well as how uranium is processed from ore to fuel.

8

Theory of nuclear reactions  

SciTech Connect

The book presents a theory of nuclear reaction. An account is given of the nonrelativistic nuclear reaction theory. The R - matrix description of nuclear reactions is considered and the dispersion method is formulated. Mechanisms of nuclear reactions and their relationship are studied in detail. Attention is paid to nuclear reactions involving the compound nuclear formation and to direct nuclear processes. The optical model the diffraction approach and high - energy diffraction nuclear processes involving composite particles are discussed.

Sitenko, A.G.

1990-01-01T23:59:59.000Z

9

Nuclear Reactions in Stars  

Science Journals Connector (OSTI)

21 February 1961 research-article Nuclear Reactions in Stars T. G. Cowling Thermonuclear reactions important for the generation of stellar energy during different phases of stellar evolution are discussed. The Royal...

1961-01-01T23:59:59.000Z

10

Controlled Nuclear Fusion Reactions  

Science Journals Connector (OSTI)

... THE presentation of full and authoritative accounts of research on controlled nuclear fusion reactions was a major feature of the second Geneva Conference on the Peaceful Uses of ...

R. S. PEASE

1958-10-18T23:59:59.000Z

11

Neutrino nuclear response and photo nuclear reaction  

E-Print Network (OSTI)

Photo nuclear reactions are shown to be used for studying neutrino/weak nuclear responses involved in astro-neutrino nuclear interactions and double beta decays. Charged current weak responses for ground and excited states are studied by using photo nuclear reactions through isobaric analog states of those states, while neutral current weak responses for excited states are studied by using photo nuclear reactions through the excited states. The weak interaction strengths are studied by measuring the cross sections of the photo nuclear reactions, and the spin and parity of the state are studied by measuring angular correlations of particles emitted from the photo nuclear reactions. Medium-energy polarized photons obtained from laser photons scattered off GeV electrons are very useful. Nuclear responses studied by photo nuclear reactions are used to evaluate neutrino/weak nuclear responses, i.e. nuclear beta and double beta matrix elements and neutrino nuclear interactions, and to verify theoretical calculations for them.

H. Ejiri; A. I. Titov; M. Boswell; A. Young

2013-11-10T23:59:59.000Z

12

Nuclear structure and nuclear reactions | Argonne Leadership...  

NLE Websites -- All DOE Office Websites (Extended Search)

the production Automatic Dynamic Load Balancing (ADLB) library on the BGP. Steve Pieper, Argonne National Laboratory Nuclear structure and nuclear reactions PI Name: James Vary PI...

13

A novel capillary polymerase chain reaction machine  

E-Print Network (OSTI)

I built a novel prototype capillary polymerase chain reaction machine. The purpose was to perform a single reaction as fast as possible with a reaction volume - 100 nl. The PCR mix is in the form of a 1 /1 droplet that ...

Chiou, Jeffrey Tsungshuan

2001-01-01T23:59:59.000Z

14

Nuclear Structure and Nuclear Reactions | Argonne Leadership...  

NLE Websites -- All DOE Office Websites (Extended Search)

the ab initio no-core full configuration approach," Phys. Rev. C 86, 034325 (2012) Nuclear Structure and Nuclear Reactions PI Name: James Vary PI Email: jvary@iastate.edu...

15

Nuclear Structure and Nuclear Reactions | Argonne Leadership...  

NLE Websites -- All DOE Office Websites (Extended Search)

value of 92.16 MeV and the point rms radius is 2.35 fm vs 2.33 from experiment. Nuclear Structure and Nuclear Reactions PI Name: James Vary PI Email: jvary@iastate.edu...

16

Laser induced nuclear reactions  

SciTech Connect

Dramatic improvements in laser technology since 1984 have revolutionised high power laser technology. Application of chirped-pulse amplification techniques has resulted in laser intensities in excess of 10{sup 19} W/cm{sup 2}. In the mid to late eighties, C. K. Rhodes and K. Boyer discussed the possibility of shining laser light of this intensity onto solid surfaces and to cause nuclear transitions. In particular, irradiation of a uranium target could induce electro- and photofission in the focal region of the laser. In this paper it is shown that {mu}Ci of {sup 62}Cu can be generated via the ({gamma},n) reaction by a laser with an intensity of about 10{sup 19} Wcm{sup -2}.

Ledingham, Ken; McCanny, Tom; Graham, Paul; Fang Xiao; Singhal, Ravi; Magill, Joe; Creswell, Alan; Sanderson, David; Allott, Ric; Neely, David; Norreys, Peter; Santala, Marko; Zepf, Matthew; Watts, Ian; Clark, Eugene; Krushelnick, Karl; Tatarakis, Michael; Dangor, Bucker; Machecek, Antonin; Wark, Justin [Department of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, Scotland (United Kingdom); European Commission, Institute for Transuranic Elements, Karlsruhe, Postfach 2340, D-76125 (Germany); Scottish Universities Research and Reactor Centre, East Kilbride, Glasgow G75 0QU (United Kingdom); Rutherford Appleton Laboratory, Chilton, Didcot (United Kingdom); Blackett Laboratory, Imperial College, London SW7 2BZ (United Kingdom); Clarendon Laboratory, Department of Physics, University of Oxford, OX1 3PU (United Kingdom)

1998-12-16T23:59:59.000Z

17

Nuclear Reactions & Scaling Arguments 11 October 2011  

E-Print Network (OSTI)

Nuclear Reactions & Scaling Arguments 11 October 2011 Goals · Review nuclear reaction rates · Practice using scaling arguments Nuclear Reactions 1. Consider the simple reaction A k1 ---- B k2 ---- C = 3. #12;nuclear reactions & scaling arguments 2 3. Frequently, we approximate nuclear reaction rates

Militzer, Burkhard

18

Electrochemical Branched-DNA Assay for Polymerase Chain Reaction...  

NLE Websites -- All DOE Office Websites (Extended Search)

Branched-DNA Assay for Polymerase Chain Reaction-Free Detection and Quantification of Oncogenes in Messenger RNA Electrochemical Branched-DNA Assay for Polymerase Chain...

19

Dual phase multiplex polymerase chain reaction  

DOE Patents (OSTI)

Highly specific and sensitive methods were developed for multiplex amplification of nucleic acids on supports such as microarrays. Based on a specific primer design, methods include five types of amplification that proceed in a reaction chamber simultaneously. These relate to four types of multiplex amplification of a target DNA on a solid support, directed by forward and reverse complex primers immobilized to the support and a fifth type--pseudo-monoplex polymerase chain reaction (PCR) of multiple targets in solution, directed by a single pair of unbound universal primers. The addition of the universal primers in the reaction mixture increases the yield over the traditional "bridge" amplification on a solid support by approximately ten times. Methods that provide multitarget amplification and detection of as little as 0.45-4.5.times.10.sup.-12 g (equivalent to 10.sup.2-10.sup.3 genomes) of a bacterial genomic DNA are disclosed.

Pemov, Alexander (Charlottesville, VA); Bavykin, Sergei (Darien, IL)

2008-10-07T23:59:59.000Z

20

Nuclear excitation and precompound nuclear reactions  

Science Journals Connector (OSTI)

The angular distribution of nucleons emitted in nucleon-induced precompound nuclear reactions are calculated taking into account the effect of excitation on the kinematics of nucleon-nucleon scattering inside the target-plus-projectile system. The results are compared with quantum mechanical calculations and those of reaction models based on a pure nucleon-nucleon collision picture.

Anuradha De; Siddhartha Ray; Sudip Kumar Ghosh

1988-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Securing the Sustainability of Global Medical Nuclear Supply Chains  

E-Print Network (OSTI)

Securing the Sustainability of Global Medical Nuclear Supply Chains Through Economic Cost Recovery University of Massachusetts Amherst Securing the Sustainability of Medical Nuclear Supply Chains #12 of Massachusetts Amherst Securing the Sustainability of Medical Nuclear Supply Chains #12;This presentation

Nagurney, Anna

22

Nuclear Reactions & Scaling Arguments 11 October 2011  

E-Print Network (OSTI)

Nuclear Reactions & Scaling Arguments 11 October 2011 Goals · Review nuclear reaction rates · Practice using scaling arguments Nuclear Reactions 1. Consider the simple reaction A k1 ---- B k2 ---- C rate for something like p + p D scales like n2 p. Think in microscopic terms. #12;nuclear reactions

Militzer, Burkhard

23

Integrated polymerase chain reaction/electrophoresis instrument  

DOE Patents (OSTI)

A new approach and instrument for field identification of micro-organisms and DNA fragments using a small and disposable device containing integrated polymerase chain reaction (PCR) enzymatic reaction wells, attached capillary electrophoresis (CE) channels, detectors, and read-out all on/in a small hand-held package. The analysis instrument may be made inexpensively, for example, of plastic, and thus is disposable, which minimizes cross contamination and the potential for false positive identification between samples. In addition, it is designed for multiple users with individual applications. The integrated PCR/CE is manufactured by the PCR well and CE channels are "stamped" into plastic depressions where conductive coatings are made in the wells and ends of the CE microchannels to carry voltage and current to heat the PCR reaction mixtures and simultaneously draw DNA bands up the CE channels. Light is transmitted through the instrument at appropriate points and detects PCR bands and identifies DNA fragments by size (retention time) and quantifies each by the amount of light generated as each phototransistor positioned below each CE channel detects a passing band. The instrument is so compact that at least 100 PCR/CE reactions/analyses can be performed easily on one detection device.

Andresen, Brian D. (Livermore, CA)

2000-01-01T23:59:59.000Z

24

Nuclear Reactions at High Energy  

Science Journals Connector (OSTI)

In the quark model, nuclei (B?2) have exotic quantum numbers. Given a nuclear reaction in which certain quantum numbers are exchanged, what is the scattering amplitude at high energies, in the GeV region? Does it have Regge behavior? Is it dual? Are there multibaryon resonances? In this context we present a general survey of all high-energy nuclear reactions - mainly those involving light nuclei. For B=0 exchange reactions, like ?d??d and ?-h??0t (h?He3, t=H3), there is the impulse and rescattering (Glauber) model. For B=1 exchange we discuss the one-pion-exchange (OPE) model for pp?d?+, pd?dp, and ?d?pn, and the "knock-on" model for pd??+t, dd?tp, dh?hd, ?h?pd, and ???pt. In the case of B=2 exchange we examine the impulse and rescattering diagrams for ?d?d?, ?d?d?0, and ?d?d?, and use the OPE model to calculate cross sections for pd?t?, pt?tp, and ph?hp. Briefly considered are: (1) backward elastic scattering from heavy nuclei (pA?Ap) and (2) inclusive nuclear reactions such as N14+A?Li6+anything and pA?d¯+anything. We postulate that in general nuclear reactions have Regge behavior, but are not dual, because so far there are no exotic multibaryon resonances. Nuclear reactions appear to be completely dominated by anomalous singularities, whereas ordinary nonexotic hadron reactions appear to be dominated by normal singularities and poles.

George W. Barry

1973-03-01T23:59:59.000Z

25

Nuclear Structure and Simple Nuclear Reactions  

Science Journals Connector (OSTI)

Recently it has become increasingly evident that some assumptions in the nuclear model used for the Monte Carlo calculations yield cross section values which are not in accord with experiment. In particular, calculations of (p, pn)-reaction cross sections in the Bev energy range give values which are low by factors of two to nine when compared to experimental values. The calculated cross sections also show a smooth variation with the target atomic weight whereas the experimental values show quite an erratic variation. Reasons which have been advanced to account for this lack of agreement are the lack of a nuclear surface and failure to account for shell effects in the nuclear model used.In this work a theory is developed to take account of surface and shell effects and thereby describe the observed magnitude and variation of the cross sections for simple nuclear reactions as exemplified by the (p, pn) reaction. At multi-Bev energies to which this treatment is restricted, the main contribution to the (p, pn)-reaction cross section comes from inelastic collisions between the incident protons and target neutrons, with all the p-n collision products escaping without further interaction. Approximations and assumptions used include the impulse approximation, 0° lab scattering angle for the inelastic p-n collision products, classical trajectories for the incident and scattered particles, and a quantum-mechanical treatment for the target nucleons. The multi-Bev, n-p, cloud-chamber data was used to determine the average total exit cross section for the inelastically scattered particles. The only neutron shells in the target nucleus contributing to the (p, pn) reaction are those for which the instantaneous knocking out of a neutron creates a product-neutron hole state stable to particle emission. The combination of these assumptions gives integral expressions which, when evaluated on the IBM-701 computer for the independent particle harmonic-oscillator shell model, give the (p, pn) reaction cross sections as a function of the nuclear density distribution and the number of available shells.For the low Z nuclei where the available shells can be unambiguously determined, the results give a half-central-density radius parameter, r0, (r0=R12A13), of about 1.2 fermis compared to 1.03 fermis for the charge half radius from the electron-scattering work. Use of reasonable limits on the value of r0 allows one to set the minimum number of shells available for some targets. For example, the Zn64, Cu65, and Cu63 (p, pn) cross sections require that a large part or all the 1f72 neutrons be available, or, equivalently, that a 1f72 neutron hole state (across a major shell) in the product nucleus have less than 8- to 9-Mev excitation energy. The results also show that the energy associated with nuclear rearrangement to particle-stable product states must be less than 8 to 9 Mev. In several cases, the upper limit can be lowered considerably (to 1.5 Mev and 0 Mev in the cases of O16 and N14, respectively).

Paul A. Benioff

1960-07-01T23:59:59.000Z

26

Nuclear Recoil and Simple Nuclear Reactions  

Science Journals Connector (OSTI)

The nuclear-recoil properties of simple nuclear reactions are studied in the distorted-wave impulse approximation. Calculations of the differential recoil cross section d2?d?KdTK, and the recoil angular distribution d?d?K, for the C12(p, pn)C11 and Ni58(p, pn)Ni57 reactions at 450 MeV are presented and discussed. Relativistic kinematics are used and the calculations are not limited to coplanar events: they are valid for any type of kinematically allowed event. Harmonic-oscillator and exponential radial wave functions are used along with a complex, energy-dependent, Woods-Saxon optical potential. The calculations show appreciable differences between the exponential and harmonic-oscillator forms and also between distorted- and plane-wave calculations. In general, curves of d2?d?KdTK plotted as a function of TK for fixed ?K, show steeper narrower peaks and larger flatter tails at ?K=90° than at ?K=0° or 180°. Comparison of the recoil angular distribution for outlying target neutron shells (1p in C12 and 2p in Ni58) and interior shells (1s in C12 and 1f in Ni58) shows a definite sideways peaking for the outlying shells which is lacking for the interior shells. This effect is explained as being a result of the equatorial localization of reaction sites which is greater for outer shells than for inner shells. Comparison with the small number of experimental data available indicates satisfactory agreement, except possibly for sideways recoil angles where, according to Remsberg, another reaction mechanism may be contributing.

Paul A. Benioff and Lucy Wu Person

1965-11-22T23:59:59.000Z

27

Securing the Sustainability of Global Medical Nuclear Supply Chains  

E-Print Network (OSTI)

Securing the Sustainability of Global Medical Nuclear Supply Chains Through Economic Cost Recovery-17, 2012 University of Massachusetts Amherst Securing the Sustainability of Medical Nuclear Supply Chains-2013. University of Massachusetts Amherst Securing the Sustainability of Medical Nuclear Supply Chains #12;This

Nagurney, Anna

28

Mo Supply Chain for Nuclear Medicine Ladimer S. Nagurney  

E-Print Network (OSTI)

The 99 Mo Supply Chain for Nuclear Medicine Ladimer S. Nagurney Department of Electrical November 13, 2012 #12;Nuclear Medicine: Meeting Patient Needs with 99 Mo Ladimer S. Nagurney The 99 Mo Supply Chain #12;Background and Motivation Study of Nuclear Medicine Supply Chains is a combination

Nagurney, Anna

29

Astronomy with Radioactivities: Chapter 9, Nuclear Reactions  

E-Print Network (OSTI)

Nuclear reaction rates determine the abundances of isotopes in stellar burning processes. A multitude of reactions determine the reaction flow pattern which is described in terms of reaction network simulations. The reaction rates are determined by laboratory experiments supplemented by nuclear reaction and structure theory. We will discuss the experimental approach as well as the theoretical tools for obtaining the stellar reaction rates. A detailed analysis of a reaction is only possible for a few selected cases which will be highlighted in this section. The bulk of nuclear reaction processes is however described in terms of a statistical model approach, which relies on global nuclear structure and reaction parameters such as level density and mass and barrier penetration, respectively. We will discuss a variety of experimental facilities and techniques used in the field, this includes low energy stable beam experiments, measurements at radioactive beam accelerators, and neutron beam facilities.

M. Wiescher; T. Rauscher

2010-11-01T23:59:59.000Z

30

First-Hand Recollections of the First Self-Sustaining Chain Reaction |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

First-Hand Recollections of the First Self-Sustaining Chain First-Hand Recollections of the First Self-Sustaining Chain Reaction First-Hand Recollections of the First Self-Sustaining Chain Reaction August 3, 2012 - 4:53pm Addthis On December 2, 1942, 49 scientists, led by Enrico Fermi, made history when Chicago Pile 1 (CP-1) went critical and produced the world's first self-sustaining, controlled nuclear chain reaction. Seventy years later, two of the last surviving CP-1 pioneers, Harold Agnew and Warren Nyer, recall that historic day. Michael Hess Michael Hess Former Digital Communications Specialist, Office of Public Affairs How were the natives? A small graphite block from the pile is on display at the Museum of Science and Industry in Chicago; another can be seen at the Bradbury Science Museum in Los Alamos, NM.

31

Low-Energy Nuclear Reactions in Metals  

Science Journals Connector (OSTI)

......research-article Articles Low-Energy Nuclear Reactions in Metals Jirohta Kasagi...reactions in Pd and Au for bombarding energies between 30 and 75 keV. These...measurements clearly showed that the low energy nuclear reactions are strongly affected......

Jirohta Kasagi

2004-02-01T23:59:59.000Z

32

Medical Nuclear Supply Chain Design: A Tractable Network Model and Computational  

E-Print Network (OSTI)

Medical Nuclear Supply Chain Design: A Tractable Network Model and Computational Approach Anna Medical Nuclear Supply Chain Design #12;Outline Background and Motivation Supply Chain Challenges The Medical Nuclear Supply Chain Network Design Model The Computational Approach Summary and Suggestions

Nagurney, Anna

33

Nuclear theory for high-energy nuclear reactions of biomedical relevance  

Science Journals Connector (OSTI)

......Presentations Nuclear theory for high-energy nuclear reactions of biomedical relevance...Nuclear Data Needs for Generation IV Nuclear Energy Systems, April 5-7, 2005...2005. Nuclear theory for high-energy nuclear reactions of biomedical relevance......

A. J. Koning; M. C. Duijvestijn

2007-08-01T23:59:59.000Z

34

The Polymerase Chain Reaction and Branching Processes Fengzhu Sun  

E-Print Network (OSTI)

The Polymerase Chain Reaction and Branching Processes Fengzhu Sun Department of Mathematics, DRB is studied. We also study the distribution of the Hamming distance between two randomly chosen sequences long. The double-stranded DNA molecules are heated to near boiling temperature so that the double

Sun, Fengzhu - Sun, Fengzhu

35

Polymerase chain reaction: detection of varicella-zoster virus.  

Science Journals Connector (OSTI)

...detection of varicella-zoster virus. T Fenner A Kropec J Hubner Polymerase chain reaction...viral diagnostic tool. REFERENCES 1. Fenner, T., J. Garweg, F. Hufert, M...Clin. Microbiol. 29:76-79. Thomas Fenner Andrea Kropec Johannes Hubner Department...

T Fenner; A Kropec; J Hübner

1993-02-01T23:59:59.000Z

36

Towards Quantum Transport for Nuclear Reactions  

E-Print Network (OSTI)

Nonequilibrium Green's functions represent a promising tool for describing central nuclear reactions. Even at the single-particle level, though, the Green's functions contain more information that computers may handle in the foreseeable future. In this study, we investigate whether all the information contained in the Green's functions is necessarily relevant when describing the time evolution of nuclear reactions. For this, we carry out mean-field calculations of slab collisions in one dimension.

Danielewicz, Pawel; Barker, Brent

2009-01-01T23:59:59.000Z

37

Towards Quantum Transport for Nuclear Reactions  

E-Print Network (OSTI)

Nonequilibrium Green's functions represent a promising tool for describing central nuclear reactions. Even at the single-particle level, though, the Green's functions contain more information that computers may handle in the foreseeable future. In this study, we investigate whether all the information contained in the Green's functions is necessarily relevant when describing the time evolution of nuclear reactions. For this, we carry out mean-field calculations of slab collisions in one dimension.

Pawel Danielewicz; Arnau Rios; Brent Barker

2009-06-26T23:59:59.000Z

38

Polymerase chain reaction system using magnetic beads for analyzing a sample that includes nucleic acid  

DOE Patents (OSTI)

A polymerase chain reaction system for analyzing a sample containing nucleic acid includes providing magnetic beads; providing a flow channel having a polymerase chain reaction chamber, a pre polymerase chain reaction magnet position adjacent the polymerase chain reaction chamber, and a post pre polymerase magnet position adjacent the polymerase chain reaction chamber. The nucleic acid is bound to the magnetic beads. The magnetic beads with the nucleic acid flow to the pre polymerase chain reaction magnet position in the flow channel. The magnetic beads and the nucleic acid are washed with ethanol. The nucleic acid in the polymerase chain reaction chamber is amplified. The magnetic beads and the nucleic acid are separated into a waste stream containing the magnetic beads and a post polymerase chain reaction mix containing the nucleic acid. The reaction mix containing the nucleic acid flows to an analysis unit in the channel for analysis.

Nasarabadi, Shanavaz (Livermore, CA)

2011-01-11T23:59:59.000Z

39

Effect of Uncertainties in Nuclear Reaction Rate on Nucleosynthesis Paths  

Science Journals Connector (OSTI)

......of Theoretical Physics, Vol. 123, No...Nuclear Reaction Rate on Nucleosynthesis...Nuclear Astro- physics Compilation of Reaction Rates (NACRE),2...synthesis paths pass through 20Ne or...18O reaction rate is larger than......

Kazuyuki Yamamoto; Kiyoshi Kato; Takahiro Wada; Masahisa Ohta

2010-06-01T23:59:59.000Z

40

Nuclear structure and reactions with stored nuclei  

SciTech Connect

The use of ion-storage rings is discussed for studies of nuclear reactions and structure, with emphasis on energetic beams of short- lived, radioactive nuclei. Aspects of internal versus external luminosity are considered as well as other issues connected with the inverse kinematics of reactions induced by a circulating beam of complex nuclei. Some of the physics motivation that is driving studies with radioactive beams is described.

Henning, W.

1996-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Medical Nuclear Supply Chain Design: A Tractable Network Model and Computational  

E-Print Network (OSTI)

Medical Nuclear Supply Chain Design: A Tractable Network Model and Computational Approach Anna Chain Challenges The Medical Nuclear Supply Chain Network Design Model The Computational Approach Medical Nuclear Supply Chain Design #12;This presentation is based on the paper, "Medical Nuclear Supply

Nagurney, Anna

42

nuclear reactor  

Science Journals Connector (OSTI)

...a complex atomic apparatus used to obtain energy from nuclear fission chain reaction. Used to produce nuclear energy, radioactive isotopes, and artificial elements.... atomic pile ...

2009-01-01T23:59:59.000Z

43

Nuclear Reactions Used For Superheavy Element Research  

SciTech Connect

Some of the most fascinating questions about the limits of nuclear stability are confronted in the heaviest nuclei. How many more new elements can be synthesized? What are the nuclear and chemical properties of these exotic nuclei? Does the 'Island of Stability' exist and can we ever explore the isotopes inhabiting that nuclear region? This paper will focus on the current experimental research on the synthesis and characterization of superheavy nuclei with Z>112 from the Dubna/Livermore collaboration. Reactions using {sup 48}Ca projectiles from the U400 cyclotron and actinide targets ({sup 233,238}U, {sup 237}Np, {sup 242,244}Pu, {sup 243}Am, {sup 245,248}Cm, {sup 249}Cf) have been investigated using the Dubna Gas Filled Recoil Separator in Dubna over the last 8 years. In addition, several experiments have been performed to investigate the chemical properties of some of the observed longer-lived isotopes produced in these reactions. Some comments will be made on nuclear reactions used for the production of the heaviest elements. A summary of the current status of the upper end of the chart of nuclides will be presented.

Stoyer, Mark A. [N Division, Physical Sciences Directorate, Lawrence Livermore National Laboratory, Livermore CA 94550 (United States)

2008-04-17T23:59:59.000Z

44

Hadron Cancer Therapy: Role of Nuclear Reactions  

DOE R&D Accomplishments (OSTI)

Recently it has become feasible to calculate energy deposition and particle transport in the body by proton and neutron radiotherapy beams, using Monte Carlo transport methods. A number of advances have made this possible, including dramatic increases in computer speeds, a better understanding of the microscopic nuclear reaction cross sections, and the development of methods to model the characteristics of the radiation emerging from the accelerator treatment unit. This paper describes the nuclear reaction mechanisms involved, and how the cross sections have been evaluated from theory and experiment, for use in computer simulations of radiation therapy. The simulations will allow the dose delivered to a tumor to be optimized, whilst minimizing the dos given to nearby organs at risk.

Chadwick, M. B.

2000-06-20T23:59:59.000Z

45

Nested methylation-specific polymerase chain reaction cancer detection method  

DOE Patents (OSTI)

A molecular marker-based method for monitoring and detecting cancer in humans. Aberrant methylation of gene promoters is a marker for cancer risk in humans. A two-stage, or "nested" polymerase chain reaction method is disclosed for detecting methylated DNA sequences at sufficiently high levels of sensitivity to permit cancer screening in biological fluid samples, such as sputum, obtained non-invasively. The method is for detecting the aberrant methylation of the p16 gene, O 6-methylguanine-DNA methyltransferase gene, Death-associated protein kinase gene, RAS-associated family 1 gene, or other gene promoters. The method offers a potentially powerful approach to population-based screening for the detection of lung and other cancers.

Belinsky, Steven A. (Albuquerque, NM); Palmisano, William A. (Edgewood, NM)

2007-05-08T23:59:59.000Z

46

Nuclear Reactions by a Low-Energy Pion  

Science Journals Connector (OSTI)

......research-article Articles Nuclear Reactions by a Low-Energy Pion Toshitake Kohmura...6, December 1965 Nuclear Reactions by a Low-Energy Pion Toshitake KOHMURA...transition operator as Nuclear Reactions by a Low-Energy Pion 965 A t = ~Ti......

Toshitake Kohmura

1965-12-01T23:59:59.000Z

47

Nuclear reactions in hot stellar matter and nuclear surface deformations  

Science Journals Connector (OSTI)

Cross sections for capture reactions of charged particles in hot stellar matter turn out be increased by the quadrupole surface oscillations when the corresponding phonon energies are of the order of the star temperature. This increase is studied in a model that combines barrier distribution induced by surface oscillations and tunneling. The capture of charged particles by nuclei with well-deformed ground states is enhanced in stellar matter. It is found that the influence of quadrupole surface deformation on the nuclear reactions in stars grows when mass and proton numbers in colliding nuclei increase.

V. Yu. Denisov

2006-11-28T23:59:59.000Z

48

Identifying of meat species using polymerase chain reaction (PCR)  

SciTech Connect

Meat has been widely consumed as an important protein source in daily life of human. Furthermore, with busy and intense urban lifestyle, processed food is now one of the main protein sources of one’s diet. Consumers rely on the food labeling to decide if the meat product purchased is safe and reliable. Therefore, it is important to ensure the food labeling is done in a correct manner to avoid consumer fraud. More consumers are now concern about the food quality and safety as compared to before. This study described the meat species identification and detection method using Polymerase Chain Reaction (PCR) in 8 types of meats (cattle, buffalo, goat, sheep, chicken, duck, pork and horse). The objective of this study is to decide on the specificity of oligonucleotide sequences obtained from previous study. There were 5 proposed oligonucleotide primer in this study. The main important finding in this work is the specificity of oligonucleotide primers to raw meats. It if found that the oligonucleotide primers proposed were not specific to the local raw meat species. Therefore, further study is needed to obtain a species-specific oligonucletide primers for PCR, in order to be applied in food product testing.

Foong, Chow Ming; Sani, Norrakiah Abdullah [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor (Malaysia)

2013-11-27T23:59:59.000Z

49

Investigations of nuclear structure and nuclear reactions induced by complex projectiles  

SciTech Connect

This report discusses research in the following areas: nuclear structure; fusion reactions near and below the barrier; incomplete fusion and fragmentation reactions; and instrumentation and analysis. (LSP).

Sarantites, D.G.

1990-01-01T23:59:59.000Z

50

Medical Nuclear Supply Chain Design: A Tractable Network Model and Computational Approach  

E-Print Network (OSTI)

Medical Nuclear Supply Chain Design: A Tractable Network Model and Computational Approach Anna of medical nuclear supply chains. Our focus is on the molybdenum supply chain, which is the most commonly is of special relevance to healthcare given the medical nuclear product's widespread use as well as the aging

Nagurney, Anna

51

Forging the link between nuclear reactions and nuclear structure  

E-Print Network (OSTI)

A comprehensive description of all single-particle properties associated with the nucleus ${}^{40}$Ca is generated by employing a nonlocal dispersive optical potential capable of simultaneously reproducing all relevant data above and below the Fermi energy. The introduction of nonlocality in the absorptive potentials yields equivalent elastic differential cross sections as compared to local versions but changes the absorption profile as a function of angular momentum suggesting important consequences for the analysis of nuclear reactions. Below the Fermi energy, nonlocality is essential to allow for an accurate representation of particle number and the nuclear charge density. Spectral properties implied by $(e,e'p)$ and $(p,2p)$ reactions are correctly incorporated, including the energy distribution of about 10% high-momentum nucleons, as experimentally determined by data from Jefferson Lab. These high-momentum nucleons provide a substantial contribution to the energy of the ground state, indicating a residual attractive contribution from higher-body interactions for ${}^{40}$Ca of about 0.64 MeV/$A$.

M. H. Mahzoon; R. J. Charity; W. H. Dickhoff; H. Dussan; S. J. Waldecker

2013-12-18T23:59:59.000Z

52

The parallel reaction monitoring method contributes to a highly sensitive polyubiquitin chain quantification  

SciTech Connect

Highlights: •The parallel reaction monitoring method was applied to ubiquitin quantification. •The ubiquitin PRM method is highly sensitive even in biological samples. •Using the method, we revealed that Ufd4 assembles the K29-linked ubiquitin chain. -- Abstract: Ubiquitylation is an essential posttranslational protein modification that is implicated in a diverse array of cellular functions. Although cells contain eight structurally distinct types of polyubiquitin chains, detailed function of several chain types including K29-linked chains has remained largely unclear. Current mass spectrometry (MS)-based quantification methods are highly inefficient for low abundant atypical chains, such as K29- and M1-linked chains, in complex mixtures that typically contain highly abundant proteins. In this study, we applied parallel reaction monitoring (PRM), a quantitative, high-resolution MS method, to quantify ubiquitin chains. The ubiquitin PRM method allows us to quantify 100 attomole amounts of all possible ubiquitin chains in cell extracts. Furthermore, we quantified ubiquitylation levels of ubiquitin-proline-?-galactosidase (Ub-P-?gal), a historically known model substrate of the ubiquitin fusion degradation (UFD) pathway. In wild-type cells, Ub-P-?gal is modified with ubiquitin chains consisting of 21% K29- and 78% K48-linked chains. In contrast, K29-linked chains are not detected in UFD4 knockout cells, suggesting that Ufd4 assembles the K29-linked ubiquitin chain(s) on Ub-P-?gal in vivo. Thus, the ubiquitin PRM is a novel, useful, quantitative method for analyzing the highly complicated ubiquitin system.

Tsuchiya, Hikaru; Tanaka, Keiji, E-mail: tanaka-kj@igakuken.or.jp; Saeki, Yasushi, E-mail: saeki-ys@igakuken.or.jp

2013-06-28T23:59:59.000Z

53

Theoretical descriptions of compound-nuclear reactions: open problems & challenges  

E-Print Network (OSTI)

Compound-nuclear processes play an important role for nuclear physics applications and are crucial for our understanding of the nuclear many-body problem. Despite intensive interest in this area, some of the available theoretical developments have not yet been fully tested and implemented. We revisit the general theory of compound-nuclear reactions, discuss descriptions of pre-equilibrium reactions, and consider extensions that are needed in order to get cross section information from indirect measurements.

Brett V. Carlson; Jutta E. Escher; Mahir S. Hussein

2014-03-04T23:59:59.000Z

54

Polymerase chain reaction and synthetic DNA probes: a means of distinguishing the causative agents of syphilis and yaws?  

Science Journals Connector (OSTI)

...Polymerase chain reaction and synthetic DNA probes: a means of distinguishing...Bilthoven, The Netherlands. Synthetic DNA probes specific for either the...Polymerase chain reaction and synthetic DNA probes: a means of distinguishing...

G T Noordhoek; B Wieles; J J van der Sluis; J D van Embden

1990-06-01T23:59:59.000Z

55

Improved polymerase chain reaction (PCR) detection ofGaeumannomyces graminis including a safeguard against false negatives  

Science Journals Connector (OSTI)

A previously reported method for polymerase chain reaction (PCR) detection ofGaeumannomyces graminis was modified to simplify it, improve its specificity and decrease the possibility of contamination of the assay...

Elaine Ward

1995-09-01T23:59:59.000Z

56

Gas-phase combustion processes in light of the theory of non-isothermal chain reactions  

Science Journals Connector (OSTI)

The presented experimental and theoretical results demonstrate, in contrast to the concept commonly accepted until recently, the key role of the branching-chain reaction mechanism in gas-phase combustion processes

V. V. Azatyan

2014-02-01T23:59:59.000Z

57

Microscopic theory of protein folding rates. II. Local reaction coordinates and chain dynamics  

E-Print Network (OSTI)

Microscopic theory of protein folding rates. II. Local reaction coordinates and chain dynamics John involved in barrier crossing for protein folding are investigated in terms of the chain dynamics of the polymer backbone, completing the microscopic description of protein folding presented in the preceding

Takada, Shoji

58

NUCLEAR WASTE VITRIFICATION EFFICIENCY COLD CAP REACTIONS  

SciTech Connect

The cost and schedule of nuclear waste treatment and immobilization are greatly affected by the rate of glass production. Various factors influence the performance of a waste-glass melter. One of the most significant, and also one of the least understood, is the process of batch melting. Studies are being conducted to gain fundamental understanding of the batch reactions, particularly those that influence the rate of melting, and models are being developed to link batch makeup and melter operation to the melting rate. Batch melting takes place within the cold cap, i.e., a batch layer floating on the surface of molten glass. The conversion of batch to glass consists of various chemical reactions, phase transitions, and diffusion-controlled processes. These include water evaporation (slurry feed contains as high as 60% water), gas evolution, the melting of salts, the formation of borate melt, reactions of borate melt with molten salts and with amorphous oxides (Fe{sub 2}O{sub 3} and Al{sub 2}O{sub 3}), the formation of intermediate crystalline phases, the formation of a continuous glass-forming melt, the growth and collapse of primary foam, and the dissolution of residual solids. To this list we also need to add the formation of secondary foam that originates from molten glass but accumulates on the bottom of the cold cap. This study presents relevant data obtained for a high-level-waste melter feed and introduces a one-dimensional (1D) mathematical model of the cold cap as a step toward an advanced three-dimensional (3D) version for a complete model of the waste glass melter. The 1D model describes the batch-to-glass conversion within the cold cap as it progresses in a vertical direction. With constitutive equations and key parameters based on measured data, and simplified boundary conditions on the cold-cap interfaces with the glass melt and the plenum space of the melter, the model provides sensitivity analysis of the response of the cold cap to the batch makeup and melter conditions. The model demonstrates that batch foaming has a decisive influence on the rate of melting. Understanding the dynamics of the foam layer at the bottom of the cold cap and the heat transfer through it appears crucial for a reliable prediction of the rate of melting as a function of the melter-feed makeup and melter operation parameters. Although the study is focused on a batch for waste vitrification, the authors expect that the outcome will also be relevant for commercial glass melting.

KRUGER AA; HRMA PR; POKORNY R

2011-07-29T23:59:59.000Z

59

Nuclear waste vitrification efficiency: cold cap reactions  

SciTech Connect

The cost and schedule of nuclear waste treatment and immobilization are greatly affected by the rate of glass production. Various factors influence the performance of a waste-glass melter. One of the most significant, and also one of the least understood, is the process of batch melting. Studies are being conducted to gain fundamental understanding of the batch reactions, particularly those that influence the rate of melting, and models are being developed to link batch makeup and melter operation to the melting rate. Batch melting takes place within the cold cap, i.e., a batch layer floating on the surface of molten glass. The conversion of batch to glass consists of various chemical reactions, phase transitions, and diffusion-controlled processes. These include water evaporation (slurry feed contains as high as 60% water), gas evolution, the melting of salts, the formation of borate melt, reactions of borate melt with molten salts and with amorphous oxides (Fe2O3 and Al2O3), the formation of intermediate crystalline phases, the formation of a continuous glass-forming melt, the growth and collapse of primary foam, and the dissolution of residual solids. To this list we also need to add the formation of secondary foam that originates from molten glass but accumulates on the bottom of the cold cap. This study presents relevant data obtained for a high-level-waste melter feed and introduces a one-dimensional (1D) mathematical model of the cold cap as a step toward an advanced three-dimensional (3D) version for a complete model of the waste glass melter. The 1D model describes the batch-to-glass conversion within the cold cap as it progresses in a vertical direction. With constitutive equations and key parameters based on measured data, and simplified boundary conditions on the cold-cap interfaces with the glass melt and the plenum space of the melter, the model provides sensitivity analysis of the response of the cold cap to the batch makeup and melter conditions. The model demonstrates that batch foaming has a decisive influence on the rate of melting. Understanding the dynamics of the foam layer at the bottom of the cold cap and the heat transfer through it appears crucial for a reliable prediction of the rate of melting as a function of the melter-feed makeup and melter operation parameters. Although the study is focused on a batch for waste vitrification, the authors expect that the outcome will also be relevant for commercial glass melting.

Hrma, Pavel R.; Kruger, Albert A.; Pokorny, Richard

2012-12-15T23:59:59.000Z

60

Spallation reactions for nuclear waste transmutation and production of radioactive nuclear beams  

Science Journals Connector (OSTI)

Spallation reactions are considered an optimum neutron source for nuclear waste transmutation in accelerator-driven systems (ADS). ... They are also used to produce intense radioactive nuclear beams in ISOL facil...

J. Benlliure

2005-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Spallation reactions for nuclear waste transmutation and production of radioactive nuclear beams  

Science Journals Connector (OSTI)

Spallation reactions are considered an optimum neutron source for nuclear waste transmutation in accelerator-driven systems (ADS). ... They are also used to produce intense radioactive nuclear beams in ISOL facil...

J. Benlliurea

2005-01-01T23:59:59.000Z

62

VII. Nuclear Chemistry (Chapter 17) A. Modes of radioactive decay, nuclear reactions, fission, fusion  

E-Print Network (OSTI)

40 VII. Nuclear Chemistry (Chapter 17) A. Modes of radioactive decay, nuclear reactions, fission #12;41 These masses are not exactly integer multiples due to nuclear interactions between the protons differences via the famous formula E = mc2 . Nuclear Fusion! For example, if you combine 2 protons and two

63

E-Print Network 3.0 - alpha-induced nuclear reactions Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

nuclear reactions Search Powered by Explorit Topic List Advanced Search Sample search results for: alpha-induced nuclear reactions Page: << < 1 2 3 4 5 > >> 1 Scintillation of...

64

Low energy charged particle nuclear reaction studies with \\{SSNTDs\\}  

Science Journals Connector (OSTI)

In experimental nuclear reaction studies the most general requirement is to measure the yield and the spatial distribution of the reaction products, while their energy and type are simultaneously determined, frequently in the presence of a high background due to various types of radiation. Especially in studying low-yield nuclear processes, high efficiency and long-term stability of the applied spectroscopic method are highly desirable. In such situations, various nuclear track detection methods can be used very advantageously and successfully. Some of these methods are briefly discussed and examples are presented from our results concerning the application of nuclear track spectroscopy to different low-energy nuclear reaction studies, angular distribution and excitation function measurements.

Ilona Hunyadi

1990-01-01T23:59:59.000Z

65

Charged-Particle Thermonuclear Reaction Rates: III. Nuclear Physics Input  

E-Print Network (OSTI)

The nuclear physics input used to compute the Monte Carlo reaction rates and probability density functions that are tabulated in the second paper of this series (Paper II) is presented. Specifically, we publish the input files to the Monte Carlo reaction rate code RatesMC, which is based on the formalism presented in the first paper of this series (Paper I). This data base contains overwhelmingly experimental nuclear physics information. The survey of literature for this review was concluded in November 2009.

Christian Iliadis; Richard Longland; Art Champagne; Alain Coc

2010-04-23T23:59:59.000Z

66

Physical Mechanism of Nuclear Reactions at Low Energies  

E-Print Network (OSTI)

The physical mechanism of nuclear reactions at low energies caused by spatial extension of electron is considered. Nuclear reactions of this type represent intra-electronic processes, more precisely, the processes occurring inside the area of basic localization of electron. Distinctive characteristics of these processes are defined by interaction of the own field produced by electrically charged matter of electron with free nuclei. Heavy nucleus, appearing inside the area of basic localization of electron, is inevitably deformed because of interaction of protons with the adjoining layers of electronic cloud, which may cause nuclear fission. If there occur "inside" electron two or greater number of light nuclei, an attractive force appears between the nuclei which may result in the fusion of nuclei. The intra-electronic mechanism of nuclear reactions is of a universal character. For its realization it is necessary to have merely a sufficiently intensive stream of free electrons, i.e. heavy electric current, and as long as sufficiently great number of free nuclei. This mechanism may operate only at small energies of translational motion of the centers of mass of nuclei and electron. Because of the existence of simple mechanism of nuclear reactions at low energies, nuclear reactor turns out to be an atomic delayed-action bomb which may blow up by virtue of casual reasons, as it has taken place, apparently, in Chernobyl. The use of cold nuclear reactions for production of energy will provide mankind with cheap, practically inexhaustible, and non-polluting energy sources.

V. P. Oleinik; Yu. D Arepjev

2003-06-09T23:59:59.000Z

67

Nuclear Many-Body Physics Where Structure And Reactions Meet  

E-Print Network (OSTI)

The path from understanding a simple reaction problem of scattering or tunneling to contemplating the quantum nuclear many-body system, where structure and continuum of reaction-states meet, overlap and coexist, is a complex and nontrivial one. In this presentation we discuss some of the intriguing aspects of this route.

Naureen Ahsan; Alexander Volya

2009-06-24T23:59:59.000Z

68

Penetration Factor for Nuclear Fusion Reaction in Nonthermal Astrophysical Plasmas  

Science Journals Connector (OSTI)

......enhances the fusion penetration factor. In addition...nonthermal effect on the penetration factor is found to be...the fusion reaction rates of the - chain and the...effect on the fusion penetration factor decreases with...the energy generation rate (Choudhuri 2010) by......

Dai-Han Ki; Young-Dae Jung

2011-02-25T23:59:59.000Z

69

Catalysis of Nuclear Reactions between Hydrogen Isotopes by ?- Mesons  

Science Journals Connector (OSTI)

The mechanism by which negative ? mesons catalyze nuclear reactions between hydrogen isotopes is studied in detail. The reaction rate for the process (p+d+?-?He3+?-+5.5 Mev), observed recently by Alvarez et al., is calculated and found to be in accord with the available data. The ?- meson binds two hydrogen nuclei together in the ?-mesonic analog of the ordinary H2+ molecular ion. In their vibrational motion the nuclei have a finite, although small, probability of penetrating the Coulomb barrier to zero separation where they may undergo a nuclear reaction. The intrinsic reaction rates for other, more probable, reactions are also estimated. The results are ?0.3×106 sec-1 for the observed p-d reaction, ?0.7×1011 sec-1 for the d-d reaction, and ?0.4×1013 sec-1 for the d-t reaction. For the reaction observed by Alvarez rough estimates are made of the partial widths for nonradiative and radiative decay of the excited He3 nucleus. The ejection of the ?- meson by "internal conversion" seems somewhat less likely. Speculations are made on the release of useful amounts of nuclear energy by these catalyzed reactions. The governing factors are not the intrinsic reaction rate once the molecule is formed, but rather the time spent (?10-8 sec) by the ?- meson between the breakup of one molecule and the formation of another and the loss of ?- mesons in "dead-end" processes. These factors are such that practical power production is unlikely. In liquid deuterium, each ?- meson will catalyze only ?10 reactions in its lifetime, while for the d-t process it will induce ?100 disintegrations. A longer lived particle will not be able to catalyze appreciably more reactions.

J. D. Jackson

1957-04-15T23:59:59.000Z

70

Direct reactions for nuclear structure and nuclear astrophysics  

SciTech Connect

Direct reactions are powerful probes for studying the atomic nucleus. Modern direct reaction studies are illuminating both the fundamental nature of the nucleus and its role in nucleosynthetic processes occurring in the cosmos. This report covers experiments using knockout reactions on neutron-deficient fragmentation beams, transfer reactions on fission fragment beams, and theoretical sensitivity studies relating to the astrophysical r-process. Results from experiments on 108,106Sn at the NSCL, and on 131Sn at HRIBF are presented as well as the results from the nucleosynthesis study.

Jones, Katherine Louise [University of Tennessee] (ORCID:0000000173351379)

2014-12-18T23:59:59.000Z

71

Nuclear theory for high-energy nuclear reactions of biomedical relevance  

Science Journals Connector (OSTI)

......as MCNP(X), activation and reactor codes rely on a complete description of a nuclear reaction in a data file, and not...of the International Workshop on Nuclear Data Needs for Generation IV Nuclear Energy Systems, April 5-7......

A. J. Koning; M. C. Duijvestijn

2007-08-01T23:59:59.000Z

72

From Stopping to Viscosity in Nuclear Reactions  

SciTech Connect

Data on stopping in intermediate-energy central heavy-ion collisions are analyzed following transport theory based on the Boltzmann equation. In consequence, values of nuclear shear viscosity are inferred. The inferred values are significantly larger than obtained for free nucleon dispersion relations and free nucleon-nucleon cross sections.

Danielewicz, Pawel; Barker, Brent; Shi Lijun [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy Michigan State University, East Lansing, Michigan 48824 (United States)

2009-05-07T23:59:59.000Z

73

From Stopping to Viscosity in Nuclear Reactions  

E-Print Network (OSTI)

Data on stopping in intermediate-energy central heavy-ion collisions are analyzed following transport theory based on the Boltzmann equation. In consequence, values of nuclear shear viscosity are inferred. The inferred values are significantly larger than obtained for free nucleon dispersion relations and free nucleon-nucleon cross sections.

Danielewicz, P; Shi, L

2009-01-01T23:59:59.000Z

74

From Stopping to Viscosity in Nuclear Reactions  

E-Print Network (OSTI)

Data on stopping in intermediate-energy central heavy-ion collisions are analyzed following transport theory based on the Boltzmann equation. In consequence, values of nuclear shear viscosity are inferred. The inferred values are significantly larger than obtained for free nucleon dispersion relations and free nucleon-nucleon cross sections.

P. Danielewicz; B. Barker; L. Shi

2009-03-14T23:59:59.000Z

75

On the nuclear interaction. Potential, binding energy and fusion reaction  

E-Print Network (OSTI)

The nuclear interaction is responsible for keeping neutrons and protons joined in an atomic nucleus. Phenomenological nuclear potentials, fitted to experimental data, allow one to know about the nuclear behaviour with more or less success where quantum mechanics is hard to be used. A nuclear potential is suggested and an expression for the potential energy of two nuclear entities, either nuclei or nucleons, is developed. In order to estimate parameters in this expression, some nucleon additions to nuclei are considered and a model is suggested as a guide of the addition process. Coulomb barrier and energy for the addition of a proton to each one of several nuclei are estimated by taking into account both the nuclear and electrostatic components of energy. Studies on the binding energies of several nuclei and on the fusion reaction of two nuclei are carried out.

I. Casinos

2008-05-22T23:59:59.000Z

76

Exclusive nuclear reactions: Can you count on the deuteron  

SciTech Connect

Three of the simplest nuclear reactions -- (1) electron-deuteron elastic scattering, (2) electro-disintegration of the deuteron near threshold and at high momentum transfer, and (3) photodisintegration of the deuteron at high energy -- were believed to have unique signatures for OCD effects in nuclei. The progress in the past few years with regard to these reactions will be traced and the results will be compared with recent theoretical predictions. 36 refs., 12 figs., 1 tab.

Holt, R.J.

1991-01-01T23:59:59.000Z

77

Pairing Effects in Nuclear Fusion Reaction  

E-Print Network (OSTI)

We simulate a heavy-ion collision using the canonical-basis time-dependent Hartree-Fock-Bogoliubov theory (Cb-TDHFB) treating pairing correlation in the three-dimensional coordinate space. We apply the Cb-TDHFB to 22O+22O collision with a contact-type pairing energy functional, and compare results of Cb-TDHFB and TDHF to investigate the effects of pairing correlations in nuclear fusion. Our results seem to indicate that pairing effects do not increase the fusion cross section in this system.

Ebata, Shuichiro

2013-01-01T23:59:59.000Z

78

Excitation of promising nuclear fusion reactions in picosecond laser plasmas  

SciTech Connect

The results of experiments devoted to studying the excitation of the promising nuclear fusion reactions {sup 6}Li(d, {alpha}){sup 4}He, {sup 3}He(d, p){sup 4}He, {sup 11}B(p, 3{alpha}), and {sup 7}Li(p, {alpha}){sup 4}He, along with the standard reaction D(d, n){sup 3}He, in picosecond laser plasmas are presented. For the first time, it was shown that these reactions may proceed at a moderate laser-radiation intensity of 2 x 10{sup 18} W/cm{sup 2}, the respective yield being 2 x 10{sup 3} to 10{sup 5} per laser pulse. A brief survey of the main processes responsible for the generation of fast electrons and fast ions (protons) at the front surface of the target and for the excitation of nuclear fusion reactions is given. The calculated and experimental results on the yield from nuclear fusion reactions in picosecond laser plasmas are compared. The possibilities for optimizing the yield from the promising fusion reactions excited in femto- and picosecond laser plasmas are discussed.

Belyaev, V. S.; Vinogradov, V. I.; Matafonov, A. P., E-mail: Matafonov@mtu-net.ru; Rybakov, S. M. [Central Research Institute of Machine Building (Russian Federation); Krainov, V. P. [Moscow Institute for Physics and Technology (State University) (Russian Federation); Lisitsa, V. S. [Russian Research Centre Kurchatov Institute, Institute of Nuclear Fusion (Russian Federation); Andrianov, V. P.; Ignatiev, G. N. [Research Institute for Pulse Technology (NIIPT) (Russian Federation); Bushuev, V. S.; Gromov, A. I.; Rusetsky, A. S.; Dravin, V. A. [Russian Academy of Sciences, Lebedev Institute of Physics (Russian Federation)

2009-07-15T23:59:59.000Z

79

Investigations of nuclear structure and nuclear reactions induced by complex projectiles  

SciTech Connect

The research program of our group touches five areas of nuclear physics: (1) Nuclear structure studies at high spin; (2) Studies at the interface between structure and reactions; (3) Production and study of hot nuclei; (4) Incomplete fusion and fragmentation reactions; and (5) Development and use of novel techniques and instrumentation in the above areas of research. The papers from these areas are discussed in this report.

Sarantites, D.G.

1991-01-01T23:59:59.000Z

80

Nuclear Physics A 587 (1995) 787-801 (3He,t) reactions on unstable nuclei  

E-Print Network (OSTI)

ELSEVIER NUCLEAR PHYSICS A Nuclear Physics A 587 (1995) 787-801 (3He,t) reactions on unstable,t) reactions on unstable nuclei theoretically. Since this charge-exchange reaction takes place on the nuclear in nuclear physics since we got a new tool, "beams of unstable nuclei" [1,2]. Many experimentalists have

Fernández de Córdoba, Pedro

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

REVISTA MEXICANA DE FISICA S 54 (3) 1118 DICIEMBRE 2008 Nuclear astrophysics from direct reactions  

E-Print Network (OSTI)

, and energy production in stars. 1.1. Nuclear reaction rates Low energy nuclear astrophysics requires astrophysical energies. In recent years direct reactions have been developed and applied to extract low-energy studies in nuclear astrophysics are focused on the opposite ends of the energy scale of nuclear reactions

Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

82

Nuclear fusion reaction rates for strongly coupled ionic mixtures  

SciTech Connect

We analyze the effect of plasma screening on nuclear reaction rates in dense matter composed of atomic nuclei of one or two types. We perform semiclassical calculations of the Coulomb barrier penetrability taking into account a radial mean-field potential of plasma ions. The mean-field potential is extracted from the results of extensive Monte Carlo calculations of radial pair distribution functions of ions in binary ionic mixtures. We calculate the reaction rates in a wide range of plasma parameters and approximate these rates by an analytical expression that is expected to be applicable to multicomponent ion mixtures. Also, we analyze Gamow-peak energies of reacting ions in various nuclear burning regimes. For illustration, we study nuclear burning in {sup 12}C-{sup 16}O mixtures.

Chugunov, A. I.; DeWitt, H. E. [Ioffe Physical-Technical Institute, Politekhnicheskaya 26, RU-194021 St. Petersburg (Russian Federation); Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2009-07-15T23:59:59.000Z

83

E-Print Network 3.0 - astrophysical nuclear reactions Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

Physics 2 Nuclear data for astrophysics Michael S. Smitha Summary: to determine thermonuclear reaction rates and Q-values to determine releases of nuclear energy. Astrophysical...

84

A Theory of Laser Induced Nuclear Reaction in Single Atoms  

SciTech Connect

An 'electron-bridge' mechanism of nuclear reaction in an atom or ion by ultra-intense laser fields is presented. A preliminary estimate of the intensity dependence of the rate of disintegration reaction of deuteron nucleus in deuterium atom is made for 800 nm laser fields. For intensities below 5x10{sup 21} W/cm{sup 2}, the rate of disintegration by the 'electron-bridge' mechanism is found to be small, but it rises sharply and becomes large already for {approx_equal}10{sup 22} W/cm{sup 2}.

Faisal, F. H. M.; Donner, C. [Fakultaet fuer Physik, Universitaet Bielefeld, Postfach 100131, D-33501 Bielefeld (Germany)

2010-02-02T23:59:59.000Z

85

E-Print Network 3.0 - alpha-particle-induced nuclear reactions...  

NLE Websites -- All DOE Office Websites (Extended Search)

particle-induced nuclear reactions Search Powered by Explorit Topic List Advanced Search Sample search results for: alpha-particle-induced nuclear reactions Page: << < 1 2 3 4 5 >...

86

DETERMINATION OF LOW-Z ELEMENTS IN ATMOSPHERIC AEROSOLS BY CHARGED-PARTICLE-INDUCED NUCLEAR REACTIONS  

E-Print Network (OSTI)

the nuclear reaction N14 (p,a)c 11 with low-energy protonsLOW-Z ELEMENTS IN ATMOSPHERIC AEROSOLS BY CHARGED-PARTICLE-INDUCED NUCLEAR REACTIONS Mark Steven Clemenson Energy

Clemenson, Mark Steven

2013-01-01T23:59:59.000Z

87

A string reaction coordinate for the folding of a polymer chain  

E-Print Network (OSTI)

We investigate the crystallization mechanism of a single, flexible homopolymer chain with short range attractions. For a sufficiently narrow attractive well, the system undergoes a first-order like freezing transition from an expanded disordered coil to a compact crystalline state. Based on a maximum likelihood analysis of committor values computed for configurations obtained by Wang-Landau sampling, we construct a non-linear string reaction coordinate for the coil-to-crystal transition. In contrast to a linear reaction coordinate, the string reaction coordinate captures the effect of different degrees of freedom controlling different stages of the transition. Our analysis indicates that a combination of the energy and the global crystallinity parameter Q6 provide the most accurate measure for the progress of the transition. While the crystallinity parameter Q6 is most relevant in the initial stages of the crystallization, the later stages are dominated by a decrease in the potential energy.

Leitold, Christian; Dellago, Christoph

2015-01-01T23:59:59.000Z

88

Delays associated with elementary processes in nuclear reaction simulations  

SciTech Connect

Scatterings, particularly those involving resonances, and other elementary processes do not happen instantaneously. In the context of semiclassical nuclear reaction simulations, we consider delays associated with an interaction for incident quantum wave packets. As a consequence, we express delays associated with elementary processes in terms of elements of the scattering matrix and phase shifts for elastic scattering. We show that, within the second order in density, the simulation must account for delays in scattering consistently with the mean field in order to properly model thermodynamic properties such as pressure and free-energy density. Delays associated with nucleon-nucleon and pion-nucleon scattering in free space are analyzed with their nontrivial energy dependence. Finally, an example of {ital s}-channel scattering of massless partons is studied, and scattering schemes in nuclear reaction simulations are investigated in the context of scattering delays. {copyright} {ital 1996 The American Physical Society.}

Danielewicz, P.; Pratt, S. [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States)] [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States); [Grand Accelerateur National dIons Lourds (GANIL), BP 5027, F-14021 Caen Cedex (France)

1996-01-01T23:59:59.000Z

89

Thermal distributions in stellar plasmas, nuclear reactions and solar neutrinos  

E-Print Network (OSTI)

The physics of nuclear reactions in stellar plasma is reviewed with special emphasis on the importance of the velocity distribution of ions. Then the properties (density and temperature) of the weak-coupled solar plasma are analysed, showing that the ion velocities should deviate from the Maxwellian distribution and could be better described by a weakly-nonexstensive (|q-1|solar neutrino fluxes, and on the pp neutrino energy spectrum, and analyse the consequences for the solar neutrino problem.

M. Coraddu; G. Kaniadakis; A. Lavagno; M. Lissia; G. Mezzorani; P. Quarati

1998-11-24T23:59:59.000Z

90

Time-dependent Green's functions approach to nuclear reactions  

SciTech Connect

Nonequilibrium Green's functions represent underutilized means of studying evolution of quantum many-body systems. In view of a rising computer power, an effort is underway to apply the Green's functions to the dynamics of central nuclear reactions. As the first step, mean-field evolution for the density matrix for colliding slabs is studied in one dimension. Strategy to extend the dynamics to correlations is described.

Rios, Arnau [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824-1321 (United States); Danielewicz, Pawel [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824-1321 (United States); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106-4030 (United States)

2008-04-04T23:59:59.000Z

91

Time-dependent Green's functions approach to nuclear reactions  

E-Print Network (OSTI)

Nonequilibrium Green's functions represent underutilized means of studying the time evolution of quantum many-body systems. In view of a rising computer power, an effort is underway to apply the Green's functions formalism to the dynamics of central nuclear reactions. As the first step, mean-field evolution for the density matrix for colliding slabs is studied in one dimension. The strategy to extend the dynamics to correlations is described.

Arnau Rios; Pawel Danielewicz

2008-01-28T23:59:59.000Z

92

Measurement of Gastrin and Transforming Growth Factor ? Messenger RNA Levels in Colonic Carcinoma Cell Lines by Quantitative Polymerase Chain Reaction  

Science Journals Connector (OSTI)

...reprints should be addressed. A synthetic DNA template has been constructed...polymerase chain reaction. | A synthetic DNA template has been constructed...3050, Australia ABSTRACT A synthetic DNA template has been constructed...

Graham S. Baldwin and Qun-Xing Zhang

1992-04-15T23:59:59.000Z

93

Energy-degraded RI beam for low-energy nuclear reactions  

Science Journals Connector (OSTI)

......Energy-degraded RI beam for low-energy nuclear reactions Eiji Ideguchi * * E-mail...beams are produced by intermediate energy nuclear reactions such as projectile fragmentation...various experiments using low-energy nuclear reactions can be performed and......

Eiji Ideguchi

2012-01-01T23:59:59.000Z

94

Neutrinoless $??$ decay nuclear matrix elements in an isotopic chain  

E-Print Network (OSTI)

We analyze nuclear matrix elements (NME) of neutrinoless double beta decay calculated for the Cadmium isotopes. Energy density functional methods including beyond mean field effects such as symmetry restoration and shape mixing are used. Strong shell effects are found associated to the underlying nuclear structure of the initial and final nuclei. Furthermore, we show that NME for two-neutrino double beta decay evaluated in the closure approximation, $M^{2\

Tomás R. Rodríguez; Gabriel Martínez-Pinedo

2012-10-11T23:59:59.000Z

95

Microscopic Theory of Protein Folding Rates.II: Local Reaction Coordinates and Chain Dynamics  

E-Print Network (OSTI)

The motion involved in barrier crossing for protein folding are investigated in terms of the chain dynamics of the polymer backbone, completing the microscopic description of protein folding presented in the previous paper. Local reaction coordinates are identified as collective growth modes of the unstable fluctuations about the saddle-points in the free energy surface. The description of the chain dynamics incorporates internal friction (independent of the solvent viscosity) arising from the elementary isomerizations of the backbone dihedral angles. We find that the folding rate depends linearly on the solvent friction for high viscosity, but saturates at low viscosity because of internal friction. For $\\lambda$-repressor, the calculated folding rate prefactor, along with the free energy barrier from the variational theory, gives a folding rate that agrees well with the experimentally determined rate under highly stabilizing conditions, but the theory predicts too large a folding rate at the transition midpoint. This discrepancy obtained using a fairly complete quantitative theory inspires a new set of questions about chain dynamics, specifically detailed motions in individual contact formation.

John J. Portman; Shoji Takada; Peter G. Wolynes

2000-08-30T23:59:59.000Z

96

Ab Initio Nuclear Structure and Reaction Calculations for Rare Isotopes  

SciTech Connect

We have developed a novel ab initio symmetry-adapted no-core shell model (SA-NCSM), which has opened the intermediate-mass region for ab initio investigations, thereby providing an opportunity for first-principle symmetry-guided applications to nuclear structure and reactions for nuclear isotopes from the lightest p-shell systems to intermediate-mass nuclei. This includes short-lived proton-rich nuclei on the path of X-ray burst nucleosynthesis and rare neutron-rich isotopes to be produced by the Facility for Rare Isotope Beams (FRIB). We have provided ab initio descriptions of high accuracy for low-lying (including collectivity-driven) states of isotopes of Li, He, Be, C, O, Ne, Mg, Al, and Si, and studied related strong- and weak-interaction driven reactions that are important, in astrophysics, for further understanding stellar evolution, X-ray bursts and triggering of s, p, and rp processes, and in applied physics, for electron and neutrino-nucleus scattering experiments as well as for fusion ignition at the National Ignition Facility (NIF).

Draayer, Jerry P [Louisiana State University

2014-09-28T23:59:59.000Z

97

5. Energy Production and Transport 5.1 Energy Release from Nuclear Reactions  

E-Print Network (OSTI)

5. Energy Production and Transport 5.1 Energy Release from Nuclear Reactions As mentioned when we looked at energy generation, it is now known that most of the energy radiated by stars must be released by nuclear reactions. In this section we will consider why it is that energy can be released by nuclear

Peletier, Reynier

98

Low Energy Nuclear Reaction Research at the Naval Research Laboratory D.A. Kidwell1  

E-Print Network (OSTI)

Low Energy Nuclear Reaction Research at the Naval Research Laboratory D.A. Kidwell1 , D have explored the field of Low Energy Nuclear Reactions (LENR) for about eight years focusing energy (as heat) is produced ­ neither nuclear products nor transmutations have been firmly established

Noble, James S.

99

Using Nuclear Fusion Reactions to Peer Inside the Core of a Dense...  

Office of Science (SC) Website

Using Nuclear Fusion Reactions to Peer Inside the Core of a Dense Hot Plasma Fusion Energy Sciences (FES) FES Home About Research Facilities Science Highlights Benefits of FES...

100

Nuclear transparency in 90c.m. quasielastic A,,p,2p... reactions  

E-Print Network (OSTI)

Nuclear transparency in 90c.m. ° quasielastic A,,p,2p... reactions J. Aclander,7 J. Alster,7 G Synchrotron of BNL to measure the nuclear transparency of nuclei measured in the A p,2p quasielastic of the energy dependence of the nuclear transparency. In E850 the angular dependence of the nuclear transparency

Christensen, Nelson

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

A comparative analysis of accident risks in fossil, hydro, and nuclear energy chains  

SciTech Connect

This study presents a comparative assessment of severe accident risks in the energy sector, based on the historical experience of fossil (coal, oil, natural gas, and LPG (Liquefied Petroleum Gas)) and hydro chains contained in the comprehensive Energy-related Severe Accident Database (ENSAD), as well as Probabilistic Safety Assessment (PSA) for the nuclear chain. Full energy chains were considered because accidents can take place at every stage of the chain. Comparative analyses for the years 1969-2000 included a total of 1870 severe ({>=} 5 fatalities) accidents, amounting to 81,258 fatalities. Although 79.1% of all accidents and 88.9% of associated fatalities occurred in less developed, non-OECD countries, industrialized OECD countries dominated insured losses (78.0%), reflecting their substantially higher insurance density and stricter safety regulations. Aggregated indicators and frequency-consequence (F-N) curves showed that energy-related accident risks in non-OECD countries are distinctly higher than in OECD countries. Hydropower in non-OECD countries and upstream stages within fossil energy chains are most accident-prone. Expected fatality rates are lowest for Western hydropower and nuclear power plants; however, the maximum credible consequences can be very large. Total economic damages due to severe accidents are substantial, but small when compared with natural disasters. Similarly, external costs associated with severe accidents are generally much smaller than monetized damages caused by air pollution.

Burgherr, P.; Hirschberg, S. [Paul Scherrer Institute, Villigen (Switzerland)

2008-07-01T23:59:59.000Z

102

Repulsive aspects of pairing correlation in nuclear fusion reaction  

E-Print Network (OSTI)

Numerical simulation on nuclear collisions are performed using the canonical-basis time-dependent Hartree-Fock-Bogoliubov theory (Cb-TDHFB) in the three-dimensional coordinate space. Comparing results of the Cb-TDHFB and the conventional time-dependent Hartree-Fock (TDHF) calculations, we study effects of the pairing correlation on fusion reaction of $^{22}$O+$^{22}$O, $^{52}$Ca+$^{52}$Ca, and $^{22}$O+$^{52}$Ca, using the Skyrme SkM$^*$ functional and a contact-type pairing energy functional. Although current results are yet preliminary, they may suggest that the pairing correlation could hinder the fusion probability at energies in the vicinity of the Coulomb barrier height. We also perform a calculation for heavier nuclei, $^{96}$Zn+$^{124}$Sn, which seems to suggest a similar hindrance effect.

Shuichiro Ebata; Takashi Nakatsukasa

2014-08-08T23:59:59.000Z

103

Repulsive aspects of pairing correlation in nuclear fusion reaction  

E-Print Network (OSTI)

Numerical simulation on nuclear collisions are performed using the canonical-basis time-dependent Hartree-Fock-Bogoliubov theory (Cb-TDHFB) in the three-dimensional coordinate space. Comparing results of the Cb-TDHFB and the conventional time-dependent Hartree-Fock (TDHF) calculations, we study effects of the pairing correlation on fusion reaction of $^{22}$O+$^{22}$O, $^{52}$Ca+$^{52}$Ca, and $^{22}$O+$^{52}$Ca, using the Skyrme SkM$^*$ functional and a contact-type pairing energy functional. Although current results are yet preliminary, they may suggest that the pairing correlation could hinder the fusion probability at energies in the vicinity of the Coulomb barrier height. We also perform a calculation for heavier nuclei, $^{96}$Zn+$^{124}$Sn, which seems to suggest a similar hindrance effect.

Ebata, Shuichiro

2014-01-01T23:59:59.000Z

104

The US nuclear reaction data network. Summary of the first meeting, March 13 & 14 1996  

SciTech Connect

The first meeting of the US Nuclear Reaction Data Network (USNRDN) was held at the Colorado School of Mines, March 13-14, 1996 chaired by F. Edward Cecil. The Agenda of the meeting is attached. The Network, its mission, products and services; related nuclear data and data networks, members, and organization are described in Attachment 1. The following progress reports from the members of the USNRDN were distributed prior to the meeting and are given as Attachment 2. (1) Measurements and Development of Analytic Techniques for Basic Nuclear Physics and Nuclear Applications; (2) Nuclear Reaction Data Activities at the National Nuclear Data Center; (3) Studies of nuclear reactions at very low energies; (4) Nuclear Reaction Data Activities, Nuclear Data Group; (5) Progress in Neutron Physics at Los Alamos - Experiments; (6) Nuclear Reaction Data Activities in Group T2; (7) Progress Report for the US Nuclear Reaction Data Network Meeting; (8) Nuclear Astrophysics Research Group (ORNL); (9) Progress Report from Ohio University; (10) Exciton Model Phenomenology; and (11) Progress Report for Coordination Meeting USNRDN.

NONE

1996-03-01T23:59:59.000Z

105

Charged particle assisted nuclear reactions in solid state environment: renaissance of low energy nuclear physics  

E-Print Network (OSTI)

The features of electron assisted neutron exchange processes in crystalline solids are survayed. It is stated that, contrary to expectations, the cross section of these processes may reach an observable magnitude even in the very low energy case because of the extremely huge increment caused by the Coulomb factor of the electron assisted processes and by the effect of the crystal-lattice. The features of electron assisted heavy charged particle exchange processes, electron assisted nuclear capure processes and heavy charged particle assisted nuclear processes are also overviewed. Experimental observations, which may be related to our theoretical findings, are dealt with. The anomalous screening phenomenon is related to electron assisted neutron and proton exchange processes in crystalline solids. A possible explanation of observations by Fleischmann and Pons is presented. The possibility of the phenomenon of nuclear transmutation is qualitatively explained with the aid of usual and charged particle assisted reactions. The electron assisted neutron exchange processes in pure $Ni$ and $Li-Ni$ composite systems (in the Rossi-type E-Cat) are analyzed and it is concluded that these reactions may be responsible for recent experimental observations.

Péter Kálmán; Tamás Keszthelyi

2015-02-05T23:59:59.000Z

106

Diagnosis of human cytomegalovirus-induced retinitis in human immunodeficiency virus type 1-infected subjects by using the polymerase chain reaction.  

Science Journals Connector (OSTI)

...using the polymerase chain reaction. T E Fenner J Garweg F T Hufert M Boehnke H Schmitz...the Polymerase Chain Reaction THOMAS E. FENNER,l JUSTUS GARWEG,2 FRANK T. HUFERT...Clin. N. Am. 2:495-509. 4. Fenner, T., C. Lunkenheimer, F. Hufert...

T E Fenner; J Garweg; F T Hufert; M Boehnke; H Schmitz

1991-11-01T23:59:59.000Z

107

Nuclear Reaction Cross Sections Database at BNL | U.S. DOE Office of  

Office of Science (SC) Website

Reaction Cross Sections Reaction Cross Sections Database at BNL Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives Nuclear Reaction Cross Sections Database at BNL Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: Generation and maintenance of database containing evaluated (recommended) nuclear reaction cross sections for all nuclei relevant to applied

108

Nuclear spin selection rules in chemical reactions by angular momentum algebra  

E-Print Network (OSTI)

Nuclear spin selection rules in chemical reactions by angular momentum algebra Takeshi Oka of the representations of the permutation­inversion group for both nuclear spin and rovibronic coordinate wavefunctions, those of the rotation group for nuclear spin wavefunction only are used. The method allows more

Oka, Takeshi

109

I. Nuclear Production Reaction and Chemical Isolation Procedure for 240Am II. New Superheavy Element Isotopes: 242Pu(48Ca,5n)285-114  

E-Print Network (OSTI)

the low excitation energy of the nuclear reaction results inof nuclear fusion reactions at low excitation energies withlow (1 eV – 100 keV) neutron energies. It goes on to discuss the nuclear reactions

Ellison, Paul Andrew

2011-01-01T23:59:59.000Z

110

E-Print Network 3.0 - analysis nuclear reaction Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

Powered by Explorit Topic List Advanced Search Sample search results for: analysis nuclear reaction Page: << < 1 2 3 4 5 > >> 1 As officials in Japan deal with the accumulation...

111

Low-energy nuclear transfer reactions in muonic molecules  

Science Journals Connector (OSTI)

A scheme, analogous to the linear combination of atomic orbitals, is proposed to calculate rates of reactions of nucleon-group transfer between nuclei confined in muonic molecules. It is pointed out that such rates can be rather high if the energy release of a reaction is small. As an example, the rate of the reaction p-?-10Be?t-?-8Be is calculated.

V. B. Belyaev; S. A. Rakityansky; H. Fiedeldey; S. A. Sofianos

1994-07-01T23:59:59.000Z

112

PoS(Bormio2013)041 Direct Reactions for Nuclear Astrophysics  

E-Print Network (OSTI)

PoS(Bormio2013)041 Direct Reactions for Nuclear Astrophysics C.A. Bertulani Department of Physics at the small astrophysical energies. In recent years indirect reaction methods have been developed and applied to extract low-energy astrophysical S-factors. These methods require a combination of new experimental

Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

113

Atom-split it for nuclear energy  

NLE Websites -- All DOE Office Websites (Extended Search)

Atom-split it for nuclear energy Fermi-leader of the team that produced the first self-sustaining controlled nuclear chain reaction; contributed to ending WWII Calutron-invented by...

114

arXiv:0802.3463v1[nucl-th]23Feb2008 Nuclear astrophysics from direct reactions  

E-Print Network (OSTI)

Ongoing studies in nuclear astrophysics are focused on the opposite ends of the energy scale of nuclear, and energy production in stars. A. Nuclear reaction rates Low energy nuclear astrophysics requires the knowl presented at the XXXI Symposium on Nuclear Physics held in the Hacienda Cocoyoc, Mexico, Jan. 7-10, 2008. e

Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

115

Break-up of the Larsen B Ice Shelf Triggered by Chain-Reaction Drainage of Supraglacial Lakes  

E-Print Network (OSTI)

ice-shelf thinning) would continue to reduce the critical lake 200 depth necessary to produce ring-type fractures. In addition, increased basal melting leads 201 to substantial cooling of the ice shelf interior [Sergienko et al., 2013], making... Break-up of the Larsen B Ice Shelf Triggered by Chain-Reaction 1 Drainage of Supraglacial Lakes 2 Alison F. Banwell1,2, Douglas R. MacAyeal1 and Olga V. Sergienko3 3 1The Department of Geophysical Sciences, The University of Chicago, Chicago, IL...

Banwell, Alison F.; MacAyeal, Douglas R.; Sergienko, Olga V.

2014-12-12T23:59:59.000Z

116

[Reaction mechanism studies of heavy ion induced nuclear reactions]. Annual progress report, [January 1992--February 1993  

SciTech Connect

Completed work is summarized on the topics of excitation energy division in deep-inelastic reactions and the onset of multifragmentation in La-induced reactions at E/A = 45 MeV. Magnetic fields are being calculated for the PHOBOS detector system, a two-arm multiparticle spectrometer for studying low-transverse-momentum particles produced at the Relativistic Heavy Ion Collider. The Maryland Forward Array is being developed for detection of the reaction products from very peripheral collisions; it consists of two individual units of detectors: the annular silicon detector in front and the plastic phoswich detector at back.

Mignerey, A.C.

1993-02-01T23:59:59.000Z

117

The Effective Energy in Nuclear Reactions from Exact Probability by Using the WKB Approximation  

SciTech Connect

The transmission coefficient through a Coulomb barrier in nuclear reaction is obtained by using the WKB approximation. Hence, we can determine the exact tunneling probability from this method. This probability can be applied in calculating the astrophysical thermonuclear reaction rates. One of the most important aspects in calculating the reaction rates is the value of the most effective energy, E{sub 0} for the reaction to occur. The Gamow peak produces a nonlinear equation that is solved iteratively to produce E{sub 0}.

Aziz, Azni Abdul; Yusof, Norhasliza; Kassim, Hasan Abu [Physics Department, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia)

2008-05-20T23:59:59.000Z

118

Absorption-Fluctuation Theorem for Nuclear Reactions: Brink-Axel, Incomplete Fusion and All That  

E-Print Network (OSTI)

We discuss the connection between absorption, averages and fluctuations in nuclear reactions. The fluctuations in the entrance channel result in the compound nucleus, Hauser-Feshbach, cross section, the fluctuations in the intermediate channels, result in modifications of multistep reaction cross sections, while the fluctuations in the final channel result in hybrid cross sections that can be used to describe incomplete fusion reactions. We discuss the latter in details and comment on the validity of the assumptions used in the develpoment of the Surrogate method. We also discuss the theory of multistep reactions with regards to intermediate state fluctuations and the energy dependence and non-locality of the intermediate channels optical potentials.

M. S. Hussein

2007-12-18T23:59:59.000Z

119

NUCLEAR REACTION AND STRUCTURE DATABASES OF THE NATIONAL NUCLEAR DATA CENTER.  

SciTech Connect

We discuss nuclear data resources of the National Nuclear Data Center (NNDC) of relevance to nuclear astrophysics applications. These resources include databases, tools and powerful web service at www.nndc.bnl.gov. Our objective is to provide an overview of nuclear databases, related products and demonstrate nuclear astrophysics potential of the ENDF/B-VII beta2 library. A detailed discussion on the Maxwellian neutron capture cross sections obtained from the ENDF/B-VII beta2 library is presented.

PRITYCHENKO, B.; HERMAN, M.W.; MUGHABGHAB, S.F.; OBLOZINSKY, P.; SONZOGNI, A.A.

2006-06-23T23:59:59.000Z

120

Selected Topics in High Energy Semi-Exclusive Electro-Nuclear Reactions  

E-Print Network (OSTI)

We review the present status of the theory of high energy reactions with semi-exclusive nucleon electro-production from nuclear targets. We demonstrate how the increase of transferred energies in these reactions opens a complete new window in studying the microscopic nuclear structure at small distances. The simplifications in theoretical descriptions associated with the increase of the energies are discussed. The theoretical framework for calculation of high energy nuclear reactions based on the effective Feynman diagram rules is described in details. The result of this approach is the generalized eikonal approximation (GEA), which is reduced to Glauber approximation when nucleon recoil is neglected. The method of GEA is demonstrated in the calculation of high energy electro-disintegration of the deuteron and A=3 targets. Subsequently we generalize the obtained formulae for A>3 nuclei. The relation of GEA to the Glauber theory is analyzed. Then based on the GEA framework we discuss some of the phenomena which can be studied in exclusive reactions, these are: nuclear transparency and short-range correlations in nuclei. We illustrate how light-cone dynamics of high-energy scattering emerge naturally in high energy electro-nuclear reactions.

Misak M. Sargsian

2001-10-21T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Production of58Co in a nuclear reactor under particular consideration of interfering nuclear reactions  

Science Journals Connector (OSTI)

A method for the discrimination of side reactions is described. This method of reducing interfering reactions is introduced by the special example of the58Co production from natural nickel via the58Ni/n,p/58Co re...

H. -J. Lincke

1984-11-01T23:59:59.000Z

122

PoS(NIC-IX)040 Direct reactions in/for astrophysics  

E-Print Network (OSTI)

on the opposite ends of the energy scale of nuclear reactions: (a) the very high and (b) the very low relative scale are the low energy reactions of importance for stellar evolution. Chains of nuclear reactions lead reactions methods have been developed and applied to extract low-energy astrophysical S

Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

123

Activation cross sections of $\\alpha$-particle induced nuclear reactions on hafnium and deuteron induced nuclear reaction on tantalum: production of $^{178}$W/$^{178m}$Ta generator  

E-Print Network (OSTI)

In the frame of a systematic study of charged particle production routes of medically relevant radionuclei, the excitation function for indirect production of $^{178m}$Ta through $^{nat}$Hf($\\alpha$,xn)$^{178}$W-$^{178m}$Ta nuclear reaction was measured for the first time up to 40 MeV. In parallel, the side reactions $^{nat}$Hf($\\alpha$,x)$^{179,177,176,175}$W, $^{183,182,178g,177,176,175}$Ta, $^{179m,177m,175}$Hf were also assessed. Stacked foil irradiation technique and $\\gamma$-ray spectrometry were used. New experimental cross section data for the $^{nat}$Ta(d,xn)$^{178}$W reaction are also reported up to 40 MeV. The measured excitation functions are compared with the results of the ALICE-IPPE, and EMPIRE nuclear reaction model codes and with the TALYS 1.4 based data in the TENDL-2013 library. The thick target yields were deduced and compared with yields of other charged particle ((p,4n), (d,5n) and ($^3$He,x)) production routes for $^{178}$W.

Tárk'anyi, F; Ditrói, F; Hermanne, A; Ignatyuk, A V; Uddin, M S

2014-01-01T23:59:59.000Z

124

Reconversion of nuclear weapons  

E-Print Network (OSTI)

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 Chernobyl3- 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?

Kapitza, Sergei P

1993-01-01T23:59:59.000Z

125

Determining the density dependence of the nuclear symmetry energy using heavy-ion reactions  

E-Print Network (OSTI)

We review recent progress in the determination of the subsaturation density behavior of the nuclear symmetry energy from heavy-ion collisions as well as the theoretical progress in probing the high density behavior of the symmetry energy in heavy-ion reactions induced by high energy radioactive beams. We further discuss the implications of these results for the nuclear effective interactions and the neutron skin thickness of heavy nuclei.

Lie-Wen Chen; Che Ming Ko; Bao-An Li; Gao-Chan Yong

2007-11-12T23:59:59.000Z

126

Sensitive Detection of Rare Circulating Neuroblastoma Cells by the Reverse Transcriptase-Polymerase Chain Reaction  

Science Journals Connector (OSTI)

...total volume of 50 n\\. One hundred units MMV reverse transcriptase (BRL) were added, and the reaction was allowed to pro ceed at 41 Cfor 1 h. The PCR mixture consisted of 5 n\\ 10 x Taq RT buffer (400 mm KC1, 0.1% gelatin), 5 n\\ 1 HIMdeoxynucleotide...

Leonard A. Mattano, Jr.; Thomas J. Moss; Stephen G. Emerson

1992-09-01T23:59:59.000Z

127

Application of Dissolution Dynamic Nuclear Polarization to the Characterization of Reactions Involving Large Molecules  

E-Print Network (OSTI)

Determination of the pseudo first order reaction rate constant k?, using integrals from each peak of styrene monomer in the three reactions. ........ 88 IV-3 Apparent relaxation rates of the anionic living ends of polystyrene (rP), of polystyrene..., and of styrene monomer (rM). a Both carbons #5 are equivalent in styrene monomer.b These values are overall relaxation rates for the standard polystyrene, not the rates for the specific living chain ends. Since signals of atoms #3 & #4 in polystyrene were...

Lee, Youngbok

2013-03-13T23:59:59.000Z

128

Global nuclear power supply chains and the rise of China's nuclear industry ; Nuclear power supply chains in China : following established rules or redefining the industry? ; Rise of China's nuclear industry .  

E-Print Network (OSTI)

??China has embarked on a massive expansion of nuclear power that may fundamentally change the global nuclear industry, for better or for worse. Some industry… (more)

Metzler, Florian

2012-01-01T23:59:59.000Z

129

Nuclear Matter Incompressibility Effect on the Cross Section of Fusion Reactions with a weakly bound projectile  

E-Print Network (OSTI)

Fusion reactions with a weakly bound projectile are studied using the double-folding model along with a repulsive interaction modifying term. Using this modified potential, including nuclear matter incompressibility effects, the fusion reaction cross sections and suppression parameters are calculated for 9Be +209Bi,208Pb,29Si and 27Al reactions. The results show that applying these effects at energies near the Coulomb barrier improves the agreement between the calculated and experimental cross sections, and modifies the mean values of the suppression parameter.

Seyyedi, S A

2015-01-01T23:59:59.000Z

130

Nuclear Matter Incompressibility Effect on the Cross Section of Fusion Reactions with a weakly bound projectile  

E-Print Network (OSTI)

Fusion reactions with a weakly bound projectile are studied using the double-folding model along with a repulsive interaction modifying term. Using this modified potential, including nuclear matter incompressibility effects, the fusion reaction cross sections and suppression parameters are calculated for 9Be +209Bi,208Pb,29Si and 27Al reactions. The results show that applying these effects at energies near the Coulomb barrier improves the agreement between the calculated and experimental cross sections, and modifies the mean values of the suppression parameter.

S. A. Seyyedi; H. Golnarkar

2015-01-19T23:59:59.000Z

131

Glossary of Nuclear Waste Terms  

NLE Websites -- All DOE Office Websites (Extended Search)

measures 12 feet in diameter by 22 feet long and weighs 200 tons. Chain Reaction A self-sustaining series of nuclear fissions taking place in a reactor core. Neutrons produced in...

132

Nuclear reactions of medium and heavy target nuclei with high-energy projectiles  

Science Journals Connector (OSTI)

Nuclear reactions induced by 3·65 A GeV12C-ions and 3·65 GeV protons on target elements55Mn,59Co,nat Ni andnatCu were investigated by using the foil stack activation technique and Ge(Li) gamma-ray spectroscopy. C...

P. Kozma; B. Tumendemberel; D. Chultem

1990-01-01T23:59:59.000Z

133

A Primer for Electro-Weak Induced Low Energy Nuclear Reactions  

E-Print Network (OSTI)

In a series of papers, cited in the main body of the paper below, detailed calculations have been presented which show that electromagnetic and weak interactions can induce low energy nuclear reactions to occur with observable rates for a variety of processes. A common element in all these applications is that the electromagnetic energy stored in many relatively slow moving electrons can -under appropriate circumstances- be collectively transferred into fewer, much faster electrons with energies sufficient for the latter to combine with protons (or deuterons, if present) to produce neutrons via weak interactions. The produced neutrons can then initiate low energy nuclear reactions through further nuclear transmutations. The aim of this paper is to extend and enlarge upon various examples analyzed previously, present simplified order of magnitude estimates for each and to illuminate a common unifying theme amongst all of them.

Y. N. Srivastava; A. Widom; L. Larsen

2008-10-01T23:59:59.000Z

134

Towards a nonequilibrium Green's function description of nuclear reactions: One-dimensional mean-field dynamics  

SciTech Connect

Research Highlights: > Dynamics of central nuclear reactions. > Nonequilibrium Green's functions and Kadanoff-Baym formalism. > Adiabatic switching on of interactions. > Mean-field time evolution of nuclear slabs. > Off-diagonal spatial structure of a collision density matrix. - Abstract: Nonequilibrium Green's function methods allow for an intrinsically consistent description of the evolution of quantal many-body body systems, with inclusion of different types of correlations. In this paper, we focus on the practical developments needed to build a Green's function methodology for nuclear reactions. We start out by considering symmetric collisions of slabs in one dimension within the mean-field approximation. We concentrate on two issues of importance for actual reaction simulations. First, the preparation of the initial state within the same methodology as for the reaction dynamics is demonstrated by an adiabatic switching on of the mean-field interaction, which leads to the mean-field ground state. Second, the importance of the Green's function matrix-elements far away from the spatial diagonal is analyzed by a suitable suppression process that does not significantly affect the evolution of the elements close to the diagonal. The relative lack of importance of the far-away elements is tied to system expansion. We also examine the evolution of the Wigner function and verify quantitatively that erasing of the off-diagonal elements corresponds to averaging out of the momentum-space details in the Wigner function.

Rios, Arnau, E-mail: A.Rios@surrey.ac.uk [National Superconducting Cyclotron Laboratory, Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824-1321 (United States); Department of Physics, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom); Barker, Brent; Buchler, Mark; Danielewicz, Pawel [National Superconducting Cyclotron Laboratory, Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824-1321 (United States)

2011-05-15T23:59:59.000Z

135

Localization of a myosin heavy chain-like polypeptide to Drosophila nuclear pore complexes  

Science Journals Connector (OSTI)

...that is associated with the nuclear envelope. Further immuno...of an ATPase activity to the nuclear pore complex (1-5) as well...recent evidence dem- onstrating energy requirements for specific nuclear protein import in cell-free...

M Berrios; P A Fisher; E C Matz

1991-01-01T23:59:59.000Z

136

EXFOR basics: A short guide to the nuclear reaction data exchange format  

SciTech Connect

This manual is intended as a guide to users of nuclear reaction data compiled in the EXFOR format, and is not intended as a complete guide to the EXFOR System. EXFOR is the exchange format designed to allow transmission of nuclear data between the Nuclear Reaction Data Centers. In addition to storing the data and its` bibliographic information, experimental information, including source of uncertainties, is also compiled. The status and history of the data set is also included, e.g., the source of the data, any updates which have been made, and correlations to other data sets. EXFOR is designed for flexibility in order to meet the diverse needs of the nuclear data compilation centers. This format should not be confused with a center-to-user format. Although users may obtain data from the centers in the EXFOR format, other center-to-user formats have been developed to meet the needs of the users within each center`s own sphere of responsibility. The exchange format, as outlined, allows a large variety of numerical data tables with explanatory and bibliographic information to be transmitted in an easily machine-readable format (for checking and indicating possible errors) and a format that can be read by personnel (for passing judgment on and correcting any errors indicated by the machine). The data presently included in the EXFOR exchange include: a complete compilation of experimental neutron-induced reaction data, a selected compilation of charged-particle induced reaction data, a selected compilation of photon-induced reaction data.

McLane, V.

1996-07-01T23:59:59.000Z

137

Interplay between compound and fragments aspects of nuclear fission and heavy-ion reaction  

SciTech Connect

The scission point in nuclear fission plays a special role where one-body system changes to two-body system. Inverse of this situation is realized in heavy-ion fusion reaction where two-body system changes to one body system. Among several peculiar phenomena expected to occur during this change, we focus our attention to the behavior of compound and fragments shell effects. Some aspects of the interplay between compound and fragments shell effect are discussed related to the topics of the fission valleys in the potential energy surface of actinide nuclei and the fusion-like trajectory found in the cold fusion reaction leading to superheavy nuclei.

Moller, Peter [Los Alamos National Laboratory; Iwamoto, A [JAPAN; Ichikawa, I [JAPAN

2010-09-10T23:59:59.000Z

138

Nuclear attenuation of three-hadron systems in neutrino-induced reactions  

E-Print Network (OSTI)

For the first time, the nuclear attenuation of three hadron systems is studied in neutrino-induced reactions using the data obtained with SKAT bubble chamber. The strongest attenuation (R_3 ~ 0.6) is observed for a system carrying an overwhelming fraction of the current quark energy, as well as for a system with the smallest effective mass. An indication is obtained that the correlation effects in the nuclear attenuation play only a minor role. The experimental data are compared with predictions of the quark string fragmentation model.

N. M. Agababyan; L. Grigorian; N. Grigoryan; H. Gulkanyan; A. A. Ivanilov; Zh. Karamyan; V. A. Korotkov

2011-08-08T23:59:59.000Z

139

A study of stopping power in nuclear reactions at intermediate energies  

E-Print Network (OSTI)

We show a systematic experimental study based on INDRA data of the stopping power in central symmetric nuclear reactions. Total mass of the systems goes from 80 to 400 nucleons while the incident energy range is from 12 AMeV to 100 AMeV. The role of isospin diffusion at 32 and 45 MeV/nucleon with 124,136Xe projectiles on 112,124Sn targets performed at GANIL is also discussed. Results suggest a strong memory of the entrance channel above 20 AMeV/A (nuclear transparency) and, as such, constitute valuable tests of the microscopic transport models.

G. Lehaut; D. Durand; O. Lopez

2010-01-25T23:59:59.000Z

140

Preliminary research of health and environmental impacts and greenhouse gas emission from coal-fired power and nuclear power chains in China  

Science Journals Connector (OSTI)

The present paper treats health, environmental impacts and greenhouse gas emission resulting from both the coal-fired power chain and nuclear power chain in China. The nuclear power chain resulted in adverse health impacts 3-4 orders of magnitude lower than those from the coal-fired power chain, also radiological emissions were 1-2 orders of magnitude lower. Estimated greenhouse gas emission factors amount to 40 fold. The coal-fired power chain is considered to be one of the major sources of environmental pollution in China and rapid expansion of nuclear power in the country promises to be one of the primary ways of mitigating environmental pollution and reducing greenhouse gas emission. At the same time, of course, it is also necessary to increase the energy conversion efficiency of coal as a fuel and to minimise pollutant discharge.

Pan Ziqiang; Chen Zhuzhou; Zhu Zhiming; Xiu Binglin; Ma Zhonghai; Hao Jianzhong; He Huimin

1999-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Charged particle assisted nuclear reactions in solid state environment: renaissance of low energy nuclear physics  

E-Print Network (OSTI)

The features of electron assisted neutron exchange processes in crystalline solids are survayed. It is stated that, contrary to expectations, the cross section of these processes may reach an observable magnitude even in the very low energy case because of the extremely huge increment caused by the Coulomb factor of the electron assisted processes and by the effect of the crystal-lattice. The features of electron assisted heavy charged particle exchange processes, electron assisted nuclear capure processes and heavy charged particle assisted nuclear processes are also overviewed. Experimental observations, which may be related to our theoretical findings, are dealt with. The anomalous screening phenomenon is related to electron assisted neutron and proton exchange processes in crystalline solids. A possible explanation of observations by Fleischmann and Pons is presented. The possibility of the phenomenon of nuclear transmutation is qualitatively explained with the aid of usual and charged particle assisted r...

Kálmán, Péter

2015-01-01T23:59:59.000Z

142

High-energy nuclear quasielastic reactions: Decisive tests of nuclear-binding/pion models of the European Muon Collaboration effect  

Science Journals Connector (OSTI)

The light-cone nucleon momentum distributions obtained from nonrelativistic spectral functions or given by nuclear-binding/pion models are often used to analyze high-Q2 quasielastic and deep-inelastic (e,e’) reactions. We demonstrate that in such models the presence of non-nucleonic components causes the scattering from forward and backward moving target protons to be significantly different. Other models do not have this property. The sensitivity of current (e,e’p) and (p,pp) color transparency experiments is sufficient to observe these differences.

L. Frankfurt; G. A. Miller; M. Strikman

1992-01-06T23:59:59.000Z

143

High energy nuclear quasielastic reactions: Decisive tests of nuclear binding/pion models of the EMC effect  

SciTech Connect

The light-cone nucleon momentum distributions obtained from non- relativistic spectral functions or given by nuclear binding/pion models are often used to analyze high Q{sup 2} quasi-elastic and deep-inelastic (e,e{prime}) reactions. We demonstrate that in such models the presence of non-nucleonic components causes the scattering from forward and backward moving target protons to be significantly different. Other models do not have this property. The sensitivity of current (e,e{prime}p) and (p,pp) color transparency experiments is sufficient to observe these differences.

Frankfurt, L; Strikman, M [Washington Univ., Seattle, WA (United States). Inst. for Nuclear Theory AN SSSR, Leningrad (USSR). Inst. Yadernoj Fiziki; Miller, G A [Washington Univ., Seattle, WA (United States). Inst. for Nuclear Theory

1991-01-01T23:59:59.000Z

144

Proc. 19th Winter Workshop on Nuclear Dynamics (2003) 000000  

E-Print Network (OSTI)

Abstract. I discuss a few of the recent developments in nuclear reactions at very low energies ends of the energy scale for nuclear reactions: (a) the very high and (b) the very low relative. At the other end of the energy scale are the low energy reactions of importance for stellar evolution. A chain

Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

145

Simulations of Doppler Effects in Nuclear Reactions for AGATA Commissioning Experiments  

E-Print Network (OSTI)

The purpose of this master thesis is to simulate suitable nuclear reactions for a commissioning experiment, to be performed with the AGATA gamma-ray tracking spectrometer. The main aim of the work is to find a reaction, which gives large Doppler effects of the emitted gamma rays, with as small contribution as possible due to the energy and angular spread of the nuclei emitting the gamma rays. Inverse kinematics heavy-ion (HI) fusion reactions of the type (HI,gamma), (HI, n) on proton and deuteron targets have been studied. Target effects were investigated using the program TRIM in order to determine the impact on the Doppler effects caused by energy and angular straggling in the target material. The cross sections of a large number of reactions of protons and deuterons on nuclei with mass numbers in the range A=20-100 have been evaluated using the TALYS reaction code. The fusion-evaporation reactions, d(V-51,n)Cr-52 and d(Cl-37,n)Ar-38 were simulated in detail using the Monte Carlo code evapOR. The interactions in AGATA of the gamma rays emitted in these reactions were simulated using Geant4. The energy resolution of the gamma rays after gamma-ray tracking and Doppler correction were determined as a function of the interaction position resolution of the germanium detectors. The conclusion of this work is that of the two reactions d(V-51,n)Cr-52 is more suitable for an AGATA commissioning experiment.

Ali Al-Adili

2009-09-25T23:59:59.000Z

146

EXFOR systems manual: Nuclear reaction data exchange format. Revision 97/1  

SciTech Connect

This document describes EXFOR, the exchange format designed to allow transmission of nuclear reaction data between the members of the Nuclear Data Center Network. In addition to storing the data and its` bibliographic information, experimental information, including source of uncertainties, is also compiled. The status and history of the data set is also included, e.g., the source of the data, any updates which have been made, and correlations to other data sets. EXFOR is designed for flexibility rather than optimization of data processing in order to meet the diverse needs of the nuclear reaction data centers. The exchange format should not be confused with a center-to-user format. Although users may obtain data from the centers in the EXFOR format, other center-to-user formats have been developed to meet the needs of the users within each center`s own sphere of responsibility. The exchange format, as outlined, is designed to allow a large variety of numerical data tables with explanatory and bibliographic information to be transmitted in an easily machine-readable format (for checking and indicating possible errors) and a format that can be read by personnel (for passing judgment on and correcting any errors indicated by the machine).

McLane, V. [ed.] [comp.

1997-07-01T23:59:59.000Z

147

Reaction mechanisms in transport theories: a test of the nuclear effective interaction  

E-Print Network (OSTI)

We review recent results concerning collective excitations in neutron-rich systems and reactions between charge asymmetric systems at Fermi energies. Solving numerically self-consistent transport equations for neutrons and protons with specific initial conditions, we explore the structure of the different dipole vibrations in the $^{132}Sn$ system and investigate their dependence on the symmetry energy. We evidence the existence of a distinctive collective mode, that can be associated with the Pygmy Dipole Resonance, with an energy well below the standard Giant Dipole Resonance and isoscalar-like character, i.e. very weakly dependent on the isovector part of the nuclear effective interaction. At variance, the corresponding strength is rather sensitive to the behavior of the symmetry energy below saturation, which rules the number of excess neutrons in the nuclear surface. In reactions between charge asymmetric systems at Fermi energies, we investigate the interplay between dissipation mechanisms and isospin effects. Observables sensitive to the isospin dependent part of nuclear interaction are discussed, providing information on the symmetry energy density dependence below saturation.

M. Colonna; V. Baran; M. Di Toro; B. Frecus; Y. X. Zhang

2012-09-07T23:59:59.000Z

148

The Trojan Horse method for nuclear astrophysics: Recent results on resonance reactions  

SciTech Connect

Nuclear astrophysics aims to measure nuclear-reaction cross sections of astrophysical interest to be included into models to study stellar evolution and nucleosynthesis. Low energies, < 1 MeV or even < 10 keV, are requested for this is the window where these processes are more effective. Two effects have prevented to achieve a satisfactory knowledge of the relevant nuclear processes, namely, the Coulomb barrier exponentially suppressing the cross section and the presence of atomic electrons. These difficulties have triggered theoretical and experimental investigations to extend our knowledge down to astrophysical energies. For instance, indirect techniques such as the Trojan Horse Method have been devised yielding new cutting-edge results. In particular, I will focus on the application of this indirect method to resonance reactions. Resonances might dramatically enhance the astrophysical S(E)-factor so, when they occur right at astrophysical energies, their measurement is crucial to pin down the astrophysical scenario. Unknown or unpredicted resonances might introduce large systematic errors in nucleosynthesis models. These considerations apply to low-energy resonances and to sub-threshold resonances as well, as they may produce sizable modifications of the S-factor due to, for instance, destructive interference with another resonance.

Cognata, M. La; Pizzone, R. G. [Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania (Italy); Spitaleri, C.; Cherubini, S.; Romano, S. [Dipartimento di Fisica e Astronomia, Università di Catania, Catania, Italy and Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania (Italy); Gulino, M.; Tumino, A. [Kore University, Enna, Italy and Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania (Italy); Lamia, L. [Dipartimento di Fisica e Astronomia, Università di Catania, Catania (Italy)

2014-05-09T23:59:59.000Z

149

Macroscopic/microscopic simulation of nuclear reactions at intermediate energies. Denis Lacroix, Aymeric Van Lauwe and Dominique Durand  

E-Print Network (OSTI)

for reactions close to the fusion barrier (5-10 MeV/A) up to higher energy (100 MeV/A) and it gives access) -coalescence -test of fusion (FSI) -energy balance -classical propagation -in-flight emission Figure 1 to understand nuclear reactions at inter- mediate energies. These models provide gener- ally a rather good

Boyer, Edmond

150

Spectroscopy of element 115 decay chains  

SciTech Connect

A high-resolution a, X-ray and -ray coincidence spectroscopy experiment was conducted at the GSI Helmholtzzentrum fu r Schwerionenforschung. Thirty correlated a-decay chains were detected following the fusion-evaporation reaction 48Ca + 243Am. The observations are consistent with previous assignments of similar decay chains to originate from element Z = 115. The data includes first candidates of fingerprinting the decay step Mt --> Bh with characteristic X rays. For the first time, precise spectroscopy allows the derivation of excitation schemes of isotopes along the decay chains starting with elements Z > 112. Comprehensive Monte-Carlo simulations accompany the data analysis. Nuclear structure models provide a first level interpretation.

Rudolph, Dirk [Lund University, Sweden; Forsberg, U. [Lund University, Sweden; Golubev, P. [Lund University, Sweden; Sarmiento, L. G. [Lund University, Sweden; Yakushev, A. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Andersson, L.-L. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Di Nitto, A. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Duehllmann, Ch. E. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Gates, J. M. [Lawrence Berkeley National Laboratory (LBNL); Gregorich, K. E. [Lawrence Berkeley National Laboratory (LBNL); Gross, Carl J [ORNL; Hessberger, F. P. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Herzberg, R.-D [University of Liverpool; Khuyagbaatar, J. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Kratz, J. V. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Rykaczewski, Krzysztof Piotr [ORNL; Schaedel, M. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Aberg, S. [Lund University, Sweden; Ackermann, D. [GSI-Hemholtzzentrum fur Schwerionenforschung, Darmstadt, Germany; Block, M. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Brand, H. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Carlsson, B. G. [Lund University, Sweden; Cox, D. [University of Liverpool; Derkx, X. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Eberhardt, K. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Even, J. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Fahlander, C. [Lund University, Sweden; Gerl, J. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Jaeger, E. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Kindler, B. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Krier, J. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Kojouharov, I. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Kurz, N. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Lommel, B. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Mistry, A. [University of Liverpool; Mokry, C. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Nitsche, H. [Lawrence Berkeley National Laboratory (LBNL); Omtvedt, J. P. [Paul Scherrer Institut, Villigen, Switzerland; Papadakis, P. [University of Liverpool; Ragnarsson, I. [Lund University, Sweden; Runke, J. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Schaffner, H. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Schausten, B. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Thoerle-Pospiech, P. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Torres, T. [Gesellschaft fur Schwerionenforschung (GSI), Germany; Traut, T. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Trautmann, N. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany; Tuerler, A. [Paul Scherrer Institut, Villigen, Switzerland; Ward, A. [University of Liverpool; Ward, D. E. [Lund University, Sweden; Wiehl, N. [Johannes Gutenberg-Universitaet Mainz, Mainz, Germany

2013-01-01T23:59:59.000Z

151

Recent developments of the cascade-exciton model of nuclear reactions  

SciTech Connect

Recent developments of the Cascade-Exciton Model (CEM) of nuclear reactions are described. The improved cascade-exciton model as implemented in the code CEM97 differs from the CEM95 version by incorporating new approximations for the elementary cross sections used in the cascade, using more precise values for nuclear masses and pairing energies, using corrected systematics for the level-density parameters, and several other refinements. We have improved algorithms used in many subroutines, decreasing the computing time by up to a factor of 6 for heavy targets. We describe a number of further improvements and changes to CEM97, motivated by new data on isotope production measured at GSI. This leads us to CEM2k, a new version of the CEM code. CEM2k has a longer cascade stage, less preequilibrium emission, and evaporation from more highly excited compound nuclei compared to earlier versions. CEM2k also has other improvements and allows us to better model neutron, radionuclide, and gas production in ATW spallation targets. The increased accuracy and predictive power of the code CEM2k are shown by several examples. Further necessary work is outlined. KEYWORDS: Intranuclear cascade, preequilibrium, evaporation, and fission reactions, Monte Carlo simulations, cascade-exciton model, particle spectra, spallation and fission cross sections, GSI data

Mashnik, S. G. (Stepan G.); Sierk, A. J. (Arnold J.)

2001-01-01T23:59:59.000Z

152

Towards a nonequilibrium Green's function description of nuclear reactions: one-dimensional mean-field dynamics  

E-Print Network (OSTI)

Nonequilibrium Green's function methods allow for an intrinsically consistent description of the evolution of quantal many-body body systems, with inclusion of different types of correlations. In this paper, we focus on the practical developments needed to build a Green's function methodology for nuclear reactions. We start out by considering symmetric collisions of slabs in one dimension within the mean-field approximation. We concentrate on two issues of importance for actual reaction simulations. First, the preparation of the initial state within the same methodology as for the reaction dynamics is demonstrated by an adiabatic switching on of the mean-field interaction, which leads to the mean-field ground state. Second, the importance of the Green's function matrix-elements far away from the spatial diagonal is analyzed by a suitable suppression process that does not significantly affect the evolution of the elements close to the diagonal. The relative lack of importance of the far-away elements is tied t...

Rios, Arnau; Buchler, Mark; Danielewicz, Pawel

2010-01-01T23:59:59.000Z

153

Towards a nonequilibrium Green's function description of nuclear reactions: one-dimensional mean-field dynamics  

E-Print Network (OSTI)

Nonequilibrium Green's function methods allow for an intrinsically consistent description of the evolution of quantal many-body body systems, with inclusion of different types of correlations. In this paper, we focus on the practical developments needed to build a Green's function methodology for nuclear reactions. We start out by considering symmetric collisions of slabs in one dimension within the mean-field approximation. We concentrate on two issues of importance for actual reaction simulations. First, the preparation of the initial state within the same methodology as for the reaction dynamics is demonstrated by an adiabatic switching on of the mean-field interaction, which leads to the mean-field ground state. Second, the importance of the Green's function matrix-elements far away from the spatial diagonal is analyzed by a suitable suppression process that does not significantly affect the evolution of the elements close to the diagonal. The relative lack of importance of the far-away elements is tied to system expansion. We also examine the evolution of the Wigner function and verify quantitatively that erasing of the off-diagonal elements corresponds to averaging out of the momentum-space details in the Wigner function.

Arnau Rios; Brent Barker; Mark Buchler; Pawel Danielewicz

2010-09-01T23:59:59.000Z

154

Study of Nuclear Reactions with 11C and 15O Radioactive Ion Beams  

SciTech Connect

Nuclear reaction study with radioactive ion beams is one of the most exciting research topics in modern nuclear physics. The development of radioactive ion beams has allowed nuclear scientists and engineers to explore many unknown exotic nuclei far from the valley of nuclear stability, and to further our understanding of the evolution of the universe. The recently developed radioactive ion beam facility at the Lawrence Berkeley National Laboratory's 88-inch cyclotron is denoted as BEARS and provides {sup 11}C, {sup 14}O and {sup 15}O radioactive ion beams of high quality. These moderate to high intensity, proton-rich radioactive ion beams have been used to explore the properties of unstable nuclei such as {sup 12}N and {sup 15}F. In this work, the proton capture reaction on {sup 11}C has been evaluated via the indirect d({sup 11}C, {sup 12}N)n transfer reaction using the inverse kinematics method coupled with the Asymptotic Normalization Coefficient (ANC) theoretical approach. The total effective {sup 12}N {yields} {sup 11}C+p ANC is found to be (C{sub eff}{sup 12{sub N}}){sup 2} = 1.83 {+-} 0.27 fm{sup -1}. With the high {sup 11}C beam intensity available, our experiment showed excellent agreement with theoretical predictions and previous experimental studies. This study also indirectly confirmed that the {sup 11}C(p,{gamma}) reaction is a key step in producing CNO nuclei in supermassive low-metallicity stars, bypassing the slow triple alpha process. The newly developed {sup 15}O radioactive ion beam at BEARS was used to study the poorly known level widths of {sup 16}F via the p({sup 15}O,{sup 15}O)p reaction. Among the nuclei in the A=16, T=1 isobaric triad, many states in {sup 16}N and {sup 16}O have been well established, but less has been reported on {sup 16}F. Four states of {sup 16}F below 1 MeV have been identified experimentally: 0{sup -}, 1{sup -}, 2{sup -}, and 3{sup -} (E{sub x} = 0.0, 0.19, 0.42, and 0.72 MeV, respectively). Our study utilized R-matrix analysis and found that the 0- state has a level width of 23.1 {+-} 2.2 keV, and that the broader 1- state has a width of 91.1 {+-} 9.9 keV. The level width of the 2{sup -} state is found to be 3.3 {+-} 0.6 keV which is much narrower than the compiled value of 40 {+-} 30 keV, while a width of 14.1 {+-} 1.7 keV for the 3{sup -} state is in good agreement with the reported value (< 15 keV). These experimental level widths of all four levels are also in accordance with theoretical predictions using single particle shell model calculation.

Lee, Dongwon

2007-05-14T23:59:59.000Z

155

STARLIB: A NEXT-GENERATION REACTION-RATE LIBRARY FOR NUCLEAR ASTROPHYSICS  

SciTech Connect

STARLIB is a next-generation, all-purpose nuclear reaction-rate library. For the first time, this library provides the rate probability density at all temperature grid points for convenient implementation in models of stellar phenomena. The recommended rate and its associated uncertainties are also included. Currently, uncertainties are absent from all other rate libraries, and, although estimates have been attempted in previous evaluations and compilations, these are generally not based on rigorous statistical definitions. A common standard for deriving uncertainties is clearly warranted. STARLIB represents a first step in addressing this deficiency by providing a tabular, up-to-date database that supplies not only the rate and its uncertainty but also its distribution. Because a majority of rates are lognormally distributed, this allows the construction of rate probability densities from the columns of STARLIB. This structure is based on a recently suggested Monte Carlo method to calculate reaction rates, where uncertainties are rigorously defined. In STARLIB, experimental rates are supplemented with: (1) theoretical TALYS rates for reactions for which no experimental input is available, and (2) laboratory and theoretical weak rates. STARLIB includes all types of reactions of astrophysical interest to Z = 83, such as (p, {gamma}), (p, {alpha}), ({alpha}, n), and corresponding reverse rates. Strong rates account for thermal target excitations. Here, we summarize our Monte Carlo formalism, introduce the library, compare methods of correcting rates for stellar environments, and discuss how to implement our library in Monte Carlo nucleosynthesis studies. We also present a method for accessing STARLIB on the Internet and outline updated Monte Carlo-based rates.

Sallaska, A. L. [National Institute of Standards and Technology, Gaithersburg, MD 20899-8462 (United States); Iliadis, C.; Champange, A. E. [University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3255 (United States); Goriely, S. [Institut d'Astronomie et d'Astrophysique, Universite Libre de Bruxelles, C.P. 226, B-1050 Brussels (Belgium); Starrfield, S.; Timmes, F. X., E-mail: anne.sallaska@nist.gov [Arizona State University, Tempe, AZ 85287-1504 (United States)

2013-07-15T23:59:59.000Z

156

Production cross sections of tritium in high energy nuclear reactions with 12 GeV protons  

Science Journals Connector (OSTI)

Production cross sections of tritium in high energy nuclear reactions with 12 GeV protons were measured for Al, Co, Cu, Nb, Ag, In, Sn, Au and Pb targets. Large production cross sections of > 500 (mb) were obtained for Au and Pb targets. From their atomic weight dependence, tritium cross sections (?) in mb can be expressed as a function of target atomic weight (A) by the following simple equation: ?(A) = 95 exp(A107), which should be useful for predicting unknown cross sections. Together with other existing data at different energies, the present data suggest that there is no energy dependence of tritium cross section at proton energies above several GeV.

Masaharu Noguchi; Taichi Miura; Kenjiro Kondo; Takenori Suzuki; Yuichi Oki; Minoru Takasaki; Kazuhiro H. Tanaka; Masaharu Ieiri

1991-01-01T23:59:59.000Z

157

On the usage of electron beam as a tool to produce radioactive isotopes in photo-nuclear reactions  

E-Print Network (OSTI)

We treat the bremsstrahlung induced by initial electron beam in converter, and the production of a desirable radio-isotope due to the photo-nuclear reaction caused by this bremsstrahlung. By way of illustration, the yield of a number of some, the most in practice applicable, radio-isotopes is evaluated. The acquired findings persuade us that usage of modern electron accelerators offers a practicable way to produce the radio-isotopes needful nowadays for various valuable applications in the nuclear medicine.

G. G. Bunatian; V. G. Nikolenko; A. B. Popov

2010-12-22T23:59:59.000Z

158

Nuclear reactions with 11C and 14O radioactive ion beams  

SciTech Connect

Radioactive ion beams (RIBs) have been shown to be a useful tool for studying proton-rich nuclides near and beyond the proton dripline and for evaluating nuclear models. To take full advantage of RIBs, Elastic Resonance Scattering in Inverse Kinematics with Thick Targets (ERSIKTT), has proven to be a reliable experimental tool for investigations of proton unbound nuclei. Following several years of effort, Berkeley Experiments with Accelerated Radioactive Species (BEARS), a RIBs capability, has been developed at the Lawrence Berkeley National Laboratory's 88-Inch Cyclotron. The current BEARS provides two RIBs: a 11C beam of up to 2x108 pps intensity on target and an 14O beam of up to 3x104 pps intensity. While the development of the 11C beam has been relatively easy, a number of challenges had to be overcome to obtain the 14O beam. The excellent 11C beam has been used to investigate several reactions. The first was the 197Au(11C,xn)208-xnAt reaction, which was used to measure excitation functions for the 4n to 8n exit channels. The measured cross sections were generally predicted quite well using the fusion-evaporation code HIVAP. Possible errors in the branching ratios of ?? decays from At isotopes as well as the presence of incomplete fusion reactions probably contribute to specific overpredictions. 15F has been investigated by the p(14O,p)14O reaction with the ERSIKTT technology. Several 14O+p runs have been performed. Excellent energy calibration was obtained using resonances from the p(14N,p)14N reaction in inverse kinematics, and comparing the results to those obtained earlier with normal kinematics. The differences between 14N+p and 14O+p in the stopping power function have been evaluated for better energy calibration. After careful calibration, the energy levels of 15F were fitted with an R-matrix calculation. Spins and parities were assigned to the two observed resonances. This new measurement of the 15F ground state supports the disappearance of the Z = 8 proton magic number for odd Z, Tz=-3/2 nuclei. It is expected that future work on proton-rich nuclides will rely heavily on RIBs and/or mass separators. Currently, radioactive ion beam intensities are sufficient for the study of a reasonable number of very proton-rich nuclides.

Guo, Fanqing

2004-12-09T23:59:59.000Z

159

[Reaction mechanism studies of heavy ion induced nuclear reactions]. [Dept. of Chemistry and Biochemistry, Univ. of Maryland, College Park, Maryland  

SciTech Connect

Completed work is summarized on the topics of excitation energy division in deep-inelastic reactions and the onset of multifragmentation in La-induced reactions at E/A = 45 MeV. Magnetic fields are being calculated for the PHOBOS detector system, a two-arm multiparticle spectrometer for studying low-transverse-momentum particles produced at the Relativistic Heavy Ion Collider. The Maryland Forward Array is being developed for detection of the reaction products from very peripheral collisions; it consists of two individual units of detectors: the annular silicon detector in front and the plastic phoswich detector at back.

Mignerey, A.C.

1993-02-01T23:59:59.000Z

160

Computerized Pathway Elucidation for Hydroxyl Radical-Induced Chain Reaction Mechanisms in Aqueous Phase Advanced Oxidation Processes  

Science Journals Connector (OSTI)

The reaction network generator consists of three interrelated modules: the reaction pathway generation module, the rate constant estimation module, and the module that generates and solves the ordinary differential equations (ODEs). ... notation system is described for information processing. ... These products are explained by three primary processes (formation of CH3O• + •CH3; CH3OCH2• + •H; and CH2O + CH4), the rearrangement process (CH3O•?•CH2OH) known to be undergone by alkoxyl radicals in aq. ...

Ke Li; John Crittenden

2009-03-10T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

arXiv:nucl-th/0607015v213Jul2006 Direct reactions in/for astrophysics  

E-Print Network (OSTI)

. In recent years direct reactions methods have been developed and applied to extract low-energy astrophysical are focused on the opposite ends of the energy scale of nuclear reactions: (a) the very high and (b) the very end of the energy scale are the low energy reactions of importance for stellar evolution. Chains

Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

162

Nuclear Reaction Cross Sections Database at BNL | U.S. DOE Office...  

Office of Science (SC) Website

Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26Germantown Building 1000 Independence...

163

NUCLEAR REACTORS.  

E-Print Network (OSTI)

??Nuclear reactors are devices containing fissionable material in sufficient quantity and so arranged as to be capable of maintaining a controlled, self-sustaining NUCLEAR FISSION chain… (more)

Belachew, Dessalegn

2010-01-01T23:59:59.000Z

164

Full-energy-chain greenhouse-gas emissions: a comparison between nuclear power, hydropower, solar power and wind power  

Science Journals Connector (OSTI)

Fair comparison of the climate impacts from different energy sources can be made only by accounting for the emissions of all relevant greenhouse gases (GHGs) from the full energy chain (FENCH) of the energy sources. FENCH-GHG emission factors of most of the non-fossil fuel energies are lower than those of the fossil fuels that are in the range of 500-1200 g CO2/kW h(e). The improvement rates concerning their CO2-to-energy ratios of OECD countries and some developing countries are discussed, showing the low performance of the latter from 1965-1996. Detailed FENCH-GHG systems analyses are given for nuclear power, hydropower, and wind and solar power. The FENCH-GHG emission factor of nuclear power is 8.9 g CO2-equiv./kW h(e) and applies to light-water nuclear power plants. The main contributions are from milling, conversion of lower-grade ore, enrichment, construction and operation of the power plant, and reprocessing (if relevant). For hydropower an emission factor is reported of 16 g CO2-equiv./kW h(e) for the best investigated flat-area cold climate power plants. The main, biogenic, emission source is the water reservoir. The information on high-altitude alpine reservoir-type and run-of- river hydropower generation is limited. These plants could probably have emission factors in the low range of 5-10 g CO2-equiv./kW h(e). The FENCH CO2-equivalent emission factors of wind power systems are in the order of 15 g CO2-equiv./kW h(e). The main source is associated with the materials for the turbine and for its foundation. Solar PV and solar thermal power are in an intermediate range their current values are 100-200 and 50-80g CO2-equiv./kW h(e), respectively. GHG emissions are mainly from silicon, which dominates the PV market.

Joop F. van de Vate

2002-01-01T23:59:59.000Z

165

Proton-induced cross-sections of nuclear reactions on lead up to 37 MeV  

E-Print Network (OSTI)

Excitation function of proton induced nuclear reactions on lead for production of $^{206,205,204,203,202,201g}$Bi, $^{203cum,202m,201cum}$Pb and $^{202cum,201cum,200cum,199cum}$Tl radionuclides were measured up to 36 MeV by using activation method, stacked foil irradiation technique and $\\gamma$-ray spectrometry. The new experimental data were compared with the few earlier experimental results and with the predictions of the EMPIRE3.1, ALICE-IPPE (MENDL2p) and TALYS (TENDL-2012) theoretical reaction codes.

F. Ditrói; F. Tárkányi; S. Takács; A. Hermanne

2014-11-07T23:59:59.000Z

166

Application of evolved gas analysis to cold-cap reactions of melter feeds for nuclear waste vitrification  

SciTech Connect

In the vitrification of nuclear wastes, the melter feed (a mixture of nuclear waste and glass-forming and modifying additives) experiences multiple gas-evolving reactions in an electrical glass-melting furnace. We employed the thermogravimetry-gas chromatography-mass spectrometry (TGA-GC-MS) combination to perform evolved gas analysis (EGA). Apart from identifying the gases evolved, we performed quantitative analysis relating the weighed sum of intensities of individual gases linearly proportional with the differential themogravimetry. The proportionality coefficients were obtained by three methods based on the stoichiometry, least squares, and calibration. The linearity was shown to be a good first-order approximation, in spite of the complicated overlapping reactions.

Kruger, Albert A.; Chun, Jaehun; Hrma, Pavel R.; Rodriguez, Carmen P.; Schweiger, Michael J.

2014-04-30T23:59:59.000Z

167

Nuclear Reaction Rates — from Laboratory Experiments and in the Stellar Plasma  

Science Journals Connector (OSTI)

The two goals in nuclear astrophysics are the attempts to understand the energy generation of stars at all stages of ... nature. Both goals are closely related as nuclear processes have been identified as the eno...

Karlheinz Langanke

1991-01-01T23:59:59.000Z

168

ECOS-LINCE: A HIGH INTENSITY MULTI-ION SUPERCONDUCTING LINAC FOR NUCLEAR STRUCTURE AND REACTIONS  

E-Print Network (OSTI)

- Nuclear astrophysics - Ion-ion collisions in plasma Applied research should be also foreseen in the fields

Boyer, Edmond

169

Search for -Meson Nuclear Bound States in the \\overlinep + AZ + A-1(Z-1) Reaction  

Science Journals Connector (OSTI)

......systematic study over several nuclear targets will yield a...337 Search for -Meson Nuclear Bound States in the...Germany 7KEK (High Energy Accelerator Research Organization...8Research Center for Nuclear Physics (RCNP), Osaka...hadron mass from QCD vacuum. The mechanism is known......

P. Bühler; C. Curceanu; C. Guaraldo; O. Hartmann; K. Hicks; M. Iwasaki; T. Ishiwatari; P. Kienle; J. Marton; R. Muto; M. Niiyama; H. Noumi; H. Ohnishi; S. Okada; A. Romero Vidal; A. Sakaguchi; F. Sakuma; S. Sawada; D. Sirghi; F. Sirghi; K. Suzuki; K. Tsukada; D. J. Tedeschi; O. Vazquez Doce; E. Widmann; S. Yokkaichi; J. Zmeskal; J-PARC P29 Collaboration

2010-10-01T23:59:59.000Z

170

Cold-cap reactions in vitrification of nuclear waste glass: experiments and modeling  

SciTech Connect

Cold-cap reactions are multiple overlapping reactions that occur in the waste-glass melter during the vitrification process when the melter feed is being converted to molten glass. In this study, we used differential scanning calorimetry (DSC) to investigate cold-cap reactions in a high-alumina high-level waste melter feed. To separate the reaction heat from both sensible heat and experimental instability, we employed the run/rerun method, which enabled us to define the degree of conversion based on the reaction heat and to estimate the heat capacity of the reacting feed. Assuming that the reactions are nearly independent and can be approximated by the nth order kinetics, we obtained the kinetic parameters using the Kissinger method combined with least squares analysis. The resulting mathematical simulation of the cold-cap reactions provides a key element for the development of an advanced cold-cap model.

Chun, Jaehun [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Pierce, David A. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Pokorny, Richard [Inst. of Chemical Technology, Prague (Czech Republic); Hrma, Pavel R. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Pohang Univ. of Science and Techology (Korea, Republic of)

2013-05-10T23:59:59.000Z

171

Signature of the efficiency of solar nuclear reactions in the neutrino experiments  

E-Print Network (OSTI)

In the framework of the neutrino oscillation scenario, we discuss the influence of the uncertainty on the efficiency of the neutrino emitting reactions 1H(p,e+ \

H. Schlattl; A. Bonanno; L. Paterno

1999-02-25T23:59:59.000Z

172

Evolutionary sequences for Nova V1974 Cygni using new nuclear reaction rates and opacities  

Science Journals Connector (OSTI)

......nuclei near 26Al and beyond, such that nuclear fusion to higher mass nuclei is enhanced...nuclei near 26 Al and beyond, such that nuclear fusion to higher mass nuclei is enhanced...would again appear that improving the input physics in our simulations has worsened......

S. Starrfield; J. W. Truran; M. C. Wiescher; W. M. Sparks

1998-05-21T23:59:59.000Z

173

Evolutionary sequences for Nova V1974 Cygni using new nuclear reaction rates and opacities  

Science Journals Connector (OSTI)

......new calculations of thermonuclear runaways on 1.25-Mo...such that nuclear fusion to higher mass nuclei...new calculations of thermonuclear runaways on 1.25-M...such that nuclear fusion to higher mass nuclei...outburst is caused by a thermonuclear runaway (hereafter......

S. Starrfield; J. W. Truran; M. C. Wiescher; W. M. Sparks

1998-05-21T23:59:59.000Z

174

Nuclear reactors and the nuclear fuel cycle  

SciTech Connect

According to the author, the first sustained nuclear fission chain reaction was not at the University of Chicago, but at the Oklo site in the African country of Gabon. Proof of this phenomenon is provided by mass spectrometric and analytical chemical measurements by French scientists. The U.S. experience in developing power-producing reactors and their related fuel and fuel cycles is discussed.

Pearlman, H

1989-11-01T23:59:59.000Z

175

Neutron production from 7Li(d,xn) nuclear fusion reactions driven by high-intensity laser–target interactions  

Science Journals Connector (OSTI)

Numerical simulations of neutron production from deuterium–lithium nuclear fusion reactions have been performed. A set of differential cross sections for the 7Li(d,xn) reaction for incident deuteron energies of up to 50?MeV is assembled. The angular distribution of neutrons from a thick lithium target is simulated and benchmarked against experimental data. Two-stage neutron production from laser–target experiments has been studied as a function of laser intensity and energy. During the first stage a well collimated deuteron beam is generated using a high-intensity ultrashort pulse laser. During the second stage it is transported through a lithium target using a 3D Monte-Carlo ion beam–target deposition model. The neutron yield is estimated to be ~108?neutrons?J?1 laser energy. Some 1010 neutrons can be expected from a ~100?J petawatt-class laser. For incident deuteron energies above 1?MeV the proposed scheme for neutron production from d–Li reactions is superior to that from d–d reactions, producing a collimated beam of neutrons with higher neutron yield.

J Davis; G M Petrov; Tz Petrova; L Willingale; A Maksimchuk; K Krushelnick

2010-01-01T23:59:59.000Z

176

Production of Excess Heat Power on the basis of Low Energy Nuclear Reactions (LERN) in the Solid Medium  

SciTech Connect

The experimental data of investigation into low energy nuclear reactions (LERN) in condensed media are presented. The nuclear reactions products were researched in the solid cathode medium of a glow discharge. Hypothetically the nuclear reactions were initiated when bombarding the cathode surface by plasma ions with the energy of 1.0-2.0 keV. The results on recording excess heat power under the experiments with a high-current glow discharge in D{sub 2}, Xe and Kr, when using preliminary deuterium-charged Pd and Ti cathode samples are given. The excess heat power up to 10-15 W and efficiency up to 150 % was recorded under the experiments for Pd cathode samples in D{sub 2} discharge. The excess heat power up to 5 W and efficiency up to 150 % was recorded for the preliminary deuterium-charged Pd cathode samples in Xe and Kr discharges. At the same time the excess heat power was not observed for pure Pd cathode samples in Xe, Kr discharges. Forming the impurity nuclides ({sup 7}Li, {sup 13}C, {sup 15}N, {sup 20}Ne, {sup 29}Si, {sup 44}Ca, {sup 48}Ca, {sup 56}Fe, {sup 57}Fe, {sup 59}Co, {sup 64}Zn, {sup 66}Zn, {sup 75}As, {sup 107}Ag, {sup 109}Ag, {sup 110}Cg, {sup 111}Cg, {sup 112}Cg, {sup 114}Cg, {sup 115}In) with the efficiency up to 10{sup 13} atoms/s was recorded. Large deviation of the registered isotopes relation from the natural relation of these elements isotopes was observed. The soft X-ray radiation from the solid-state cathode medium with the intensity up to 0.01 Gy/s was recorded under the experiments with the discharge in H{sub 2}, D{sub 2}, Ar, Xe, Kr. The X-ray radiation was observed as bursts (up to 10{sup 6} photons in a burst and up to 10{sup 5} bursts a second) during the discharge burning and within 100 ms after turning off the discharge current. The results of the X-ray radiation registration showed that the exited energy levels having the lifetime up to 100 ms and more and the energy of 1.2 - 1.8 keV existed in the solid medium. The possible mechanism of producing the excess heat power and products of nuclear transmutation reactions in the solid medium with the exited energy levels was considered. (author)

Karabut, A.B. [FSUE 'LUCH', 24 Zheleznodorozhnaya St, Podolsk, Moscow Region, 142100 (Russian Federation)

2004-07-01T23:59:59.000Z

177

Standard for the determination of steady-state neutron reaction-rate distributions and reactivity of nuclear power reactors  

SciTech Connect

American National Standard ANSI/ANS*-19.3-2005 [1] covers 'The Determination of Steady-State Neutron Reaction-Rate Distributions and Reactivity of Nuclear Power Reactors'. The 2005 version is a new revision of this Standard, which had previously been issued in 1995. In this revision, the sections on the various types of power reactors have been updated to cover the latest methodologies of calculation in current use, and a section on HWR [CANDU{sup R}] reactors has been added. Also, the sections on verification and validation were revised to more fully define, discuss, and distinguish between these topics, and describe actions related to them. (authors)

Rouben, B. [Atomic Energy of Canada Limited, 2251 Speakman Drive, Mississauga, Ont. L5K 1B2 (Canada)

2006-07-01T23:59:59.000Z

178

Emission of Light Fragments from Heavy Nuclei in High Energy Nuclear Reactions  

Science Journals Connector (OSTI)

......projectile is pointed out and a new model is presented. Some...relation between emitted high energy particles and nucleonic...International Conference on High Energy Physics and Nuclear Structure...Cosmic Radiation (1964) New York: reprinted by Dover Publications......

Tatsuoki Miyazima; Kôsuke Nakamura; Yasuhiko Futami

1965-01-01T23:59:59.000Z

179

Experimental study to explore the $\\rm ^8Be$ induced nuclear reaction via the Trojan Horse Method  

E-Print Network (OSTI)

To explore a possible indirect method for $\\rm ^8Be$ induced astrophysical reactions, the $\\rm ^9Be=({}^8Be+\\it n)$ cluster structure was studied via the Trojan Horse Method. It is the first time to study a super short life nucleus $\\rm ^8Be$ via the Trojan Horse Method, and it is the first time to make a valid test for $l=1$ Trojan-horse nucleus. The $\\rm ^9Be$ nucleus is assumed to have a ($\\rm {}^8Be+\\it n$) cluster structure and used as the Trojan-horse nucleus. The $\\rm ^8Be$ nucleus acts as a participant, while the neutron is a spectator to the virtual $\\rm ^8Be +{\\it d}\\rightarrow \\alpha + {}^6Li$ reaction via a suitable 3-body reaction $\\rm ^9Be +{\\it d}\\rightarrow \\alpha + {}^6Li +\\it n$. The experimental neutron momentum distribution inside $\\rm ^9Be$ was reconstructed. The agreement between experimental and theoretical momentum distribution indicates that there should be a ($\\rm {}^8Be+\\it n$) cluster structure inside $\\rm ^9Be$. Therefor the experimental study of $\\rm ^8Be$ induced reactions, for example the experimental measurement of the $\\rm ^8Be +\\alpha \\rightarrow {}^{12}C$ reaction proceeding through the Hoyle state, is possible.

Wen Qun-Gang; Li Cheng-Bo; Zhou Shu-Hua; Bakhadir Irgaziev; Fu Yuan-Yong; Claudio Spitaleri; Marco La Cognata; Zhou Jing; Meng Qiu-Ying; Livio Lamia; Marcello Lattuada

2014-12-30T23:59:59.000Z

180

A solid-state nuclear magnetic resonance study of the reactions of propene on HY zeolite  

E-Print Network (OSTI)

, and condensation. The main objective of this study was to determine the reaction mechanism (including the observation of intermediates) for propane adsorbed on HY zeolite. C enriched propene was adsorbed on HY zeolite at room temperature, and it was observed..., as denoted by arrows C CP/MAS spectrum of propene-2- C 13 adsorbed on HY zeolite at room temperature 10 The polymerization reaction proposed in reference 13 for the adsorption of propene on HY zeolite The Bloch decay pulse sequence in NMR experiments...

Oshiro, Irene Sueko

2012-06-07T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Anomalous reaction mean free paths of nuclear projectile fragments from heavy ion collisions at 2A GeV  

Science Journals Connector (OSTI)

We present in detail the description and the analysis of two independent experiments using beams of O16 and Fe56. From their results it is concluded that the reaction mean free paths of relativistic projectile fragments, 3?Z?26, are shorter for a few centimeters after emission than at large distances, where they are compatible with values predicted from experiments on beam nuclei. The probability that this effect is due to a statistical fluctuation is <10-3. The effect is enhanced in later generations of fragments, the correlation between successive generations suggesting a kind of "memory" for the anomaly. Various systematic and spurious effects as well as conventional explanations are discussed, mainly on the basis of direct experimental observations internal to our data, and found not to explain our results. The data can be interpreted by the relatively rare occurrence of anomalous fragments that interact with an unexpectedly large cross section. The statistical methods used in the analysis of the observations are fully described.NUCLEAR REACTIONS O16 and Fe56 at 2A GeV on emulsion nuclei; reaction mean free paths of primary beams and projectile fragments measured and compared.

E. M. Friedlander; R. W. Gimpel; H. H. Heckman; Y. J. Karant; B. Judek; E. Ganssauge

1983-04-01T23:59:59.000Z

182

Quantum Many-Body Theory and Mechanisms for Low Energy Nuclear Reaction Processes in Matter  

Science Journals Connector (OSTI)

......Publishing. 28) Detailed specifications are described in a...Most recently, non-thermal nuclear fusion based...temperature with simple insulation, the low temperature...calorimeter using vacuum insulation. In all experiments...2004). 28) Detailed specifications are described in a......

Yeong E. Kim

2004-02-01T23:59:59.000Z

183

Nuclear reaction rates and energy in stellar plasmas : The effect of highly damped modes  

E-Print Network (OSTI)

The effects of the highly damped modes in the energy and reaction rates in a plasma are discussed. These modes, with wavenumbers $k \\gg k_{D}$, even being only weakly excited, with less than $k_{B}T$ per mode, make a significant contribution to the energy and screening in a plasma. When the de Broglie wavelength is much less than the distance of closest approach of thermal electrons, a classical analysis of the plasma can

Merav Opher; Luis O. Silva; Dean E. Dauger; Viktor K. Decyk; John M. Dawson

2001-05-09T23:59:59.000Z

184

The Dynamical Dipole Mode in Fusion Reactions with Exotic Nuclear Beams  

E-Print Network (OSTI)

We report the properties of the prompt dipole radiation, produced via a collective bremsstrahlung mechanism, in fusion reactions with exotic beams. We show that the gamma yield is sensitive to the density dependence of the symmetry energy below/around saturation. Moreover we find that the angular distribution of the emitted photons from such fast collective mode can represent a sensitive probe of its excitation mechanism and of fusion dynamics in the entrance channel.

V. Baran; C. Rizzo; M. Colonna; M. Di Toro; D. Pierroutsakou

2009-02-09T23:59:59.000Z

185

Coulomb reacceleration as a clock for nuclear reactions: A two-dimensional model  

Science Journals Connector (OSTI)

Reacceleration effects in the Coulomb breakup of nuclei are modeled with the two-dimensional time-dependent Schrödinger equation, extending a previous one-dimensional study. The present model better describes the individual contributions of longitudinal and transverse forces to the breakup and reacceleration. Reacceleration effects are found to preserve a strong memory of the pre-breakup phase of the reaction, as was concluded with the one-dimensional model.

C. A. Bertulani and G. F. Bertsch

1994-05-01T23:59:59.000Z

186

Chemical Effects at the Reaction Front in Corroding Spent Nuclear Fuel  

SciTech Connect

Performance assessment models of the U. S. repository at Yucca Mountain, Nevada suggest that neptunium from spent nuclear fuel is a potentially important dose contributor. A scientific understanding of how the UO{sub 2} matrix of spent nuclear fuel impacts the oxidative dissolution and reductive precipitation of Np is needed to predict the behavior of Np at the fuel surface during aqueous corrosion. Neptunium would most likely be transported as aqueous Np(V) species, but for this to occur it must first be oxidized from the Np(IV) state found within the parent spent nuclear fuel. In this paper we present synchrotron X-ray absorption spectroscopy and microscopy findings that illuminate the resultant local chemistry of neptunium and plutonium within uranium oxide spent nuclear fuel before and after corrosive alteration in an air-saturated aqueous environment. We find the Pu and Np in unaltered spent fuel to have a +4 oxidation state and an environment consistent with solid-solution in the UO{sub 2} matrix. During corrosion in an air-saturated aqueous environment, the uranium matrix is converted to uranyl (UO{sub 2}{sup 2+}) mineral assemblage that is depleted in Np and Pu relative to the parent fuel. The transition from U(IV) in the fuel to a fully U(VI) character across the corrosion front is not sharp, but occurs over a transition zone of {approx} 50 micrometers. We find evidence of a thin ({approx} 20 micrometer) layer that is enriched in Pu and Np within a predominantly U(IV) environment on the fuel side of the transition zone. These experimental observations are consistent with available data for the standard reduction potentials for NpO{sub 2}{sup +}/Np{sup 4+} and UO{sub 2}{sup 2+}/U{sup 4+} couples, which indicate that Np(IV) may not be effectively oxidized to Np(V) at the corrosion potential of uranium dioxide spent nuclear fuel in air-saturated aqueous solutions. (authors)

Fortner, Jeffrey A.; Kropf, A. Jeremy; Jerden, James L.; Cunnane, James C. [Chemical Engineering, Argonne National Laboratory, CMT/205, 9700 S. Cass Avenue, Argonne, IL, 60439 (United States)

2007-07-01T23:59:59.000Z

187

Ellipsometric, nuclear reaction analysis and high energy ion shadowing/blocking study of the oxidation of Fe(100)  

Science Journals Connector (OSTI)

The change in the ellipsometric parameter ? (??o) upon oxidation of various Ni and Fe single crystal surfaces has been related to absolute amounts of adsorbed oxygen, using nuclear reaction analysis (NRA). A linear relationship between ??o and oxygen uptake is found for coverages up to at least 1016 atoms/cm2. Using high energy ion scattering in combination with shadowing and blocking (HEIS-SB), the number of disordered Fe atoms on Fe(100) surfaces exposed to 0–2000 L O2 have been determined. Combining calibrated ellipsometry and HEIS-SB results we find that an oxide layer with average stoichiometry Fe0.95±0.07O forms. The oxide layer formed after exposure to 2000 L involves (5.0±0.5) × 1015 Fe atoms/cm2 which corresponds to 4.1±0.4 Fe(100) monolayers.

G.W.R. Leibbrandt; S. Deckers; M. Wiegel; F.H.P.M. Habraken

1991-01-01T23:59:59.000Z

188

Ellipsometric, nuclear reaction analysis and high energy ion shadowing/blocking study of the oxidation of Fe(100)  

Science Journals Connector (OSTI)

The change in the ellipsometric parameter ? (??o) upon oxidation of various Ni and Fe single crystal surfaces has been related to absolute amounts of adsorbed oxygen, using nuclear reaction analysis (NRA). A linear relationship between ??o and oxygen uptake is found for coverages up to at least 1016 atoms/cm2. Using high energy ion scattering in combination with shadowing and blocking (HEIS-SB), the number of disordered Fe atoms on Fe(100) surfaces exposed to 0–2000 L O2 have been determined. Combining calibrated ellipsometry and HEIS-SB results we find that an oxide layer with average stoichiometry Fe0.95 ± 0.07O forms. The oxide layer formed after exposure to 2000 L involves (5.0 ± 0.5) × 1015 Fe atoms/cm2 which corresponds to 4.1 ± 0.4 Fe(100) monolayers.

G.W.R Leibbrandt; S Deckers; M Wiegel; F.H.P.M Habraken

1991-01-01T23:59:59.000Z

189

Russian Military and Security Forces: A Postulated Reaction to a Nuclear Detonation  

SciTech Connect

In this paper, we will examine how Russia's military and security forces might react to the detonation of a 10-kiloton nuclear weapon placed next to the walls surrounding the Kremlin. At the time of this 'big bang,' Putin is situated outside Moscow and survives the explosion. No one claims responsibility for the detonation. No other information is known. Numerous variables will determine how events ultimately unfold and how the military and security forces will respond. Prior to examining these variables in greater detail, it is imperative to elucidate first what we mean by Russia's military and security forces.

Ball, D

2005-04-29T23:59:59.000Z

190

Acceleration of low energy nuclear reactions by formation of correlated states of interacting particles in dynamical systems  

Science Journals Connector (OSTI)

Abstract In this work the most universal mechanism of essential acceleration of low energy nuclear reactions on the basis of correlated states of interacting particles is considered. This mechanism provides a giant increase of barrier penetrability under critical conditions (low energy, high barrier), where the effectiveness of “ordinary” tunneling effects is negligibly small, and can be applied to different experiments. The physical reason of an increased barrier penetrability in correlated states is connected to the modified uncertainty relation ? p ? q ? ? 2 / 4 1 - r pq 2 for correlated states and to the increase in momentum ?p and position ?q variances with increasing of correlation coefficient rpq. We have considered preconditions and methods of formation of correlated coherent states of interacting nuclei in non-stationary dynamical systems. It was shown that in real nuclear-physical systems at r pq 2 ? 1 very sharp growth (up to a factor of 1030–10100 and more!) of Coulomb barrier penetrability at very low energy of interacting particles is possible. Several successful low-energy correlated-induced fusion experiments are discussed.

Vladimir I. Vysotskii; Stanislav V. Adamenko; Mykhaylo V. Vysotskyy

2013-01-01T23:59:59.000Z

191

On Thermonuclear Reaction Rates  

E-Print Network (OSTI)

Nuclear reactions govern major aspects of the chemical evolution od galaxies and stars. Analytic study of the reaction rates and reaction probability integrals is attempted here. Exact expressions for the reaction rates and reaction probability integrals for nuclear reactions in the case of nonresonant, modified nonresonant, screened nonresonant and resonant cases are given. These are expressed in terms of H-functions, G-functions and in computable series forms. Computational aspects are also discussed.

H. J. Haubold; A. M. Mathai

1996-12-02T23:59:59.000Z

192

Tetramethyl-1-silacycloprop-2-ene: its characterization and reactions  

SciTech Connect

The object of this research is to fully characterize and study some of the reactions of tetramethyl-1-silacycloprop-2-ene. The final characterization of this compound was accomplished by obtaining both Si29 and 13C nuclear magnetic resonance spectra. The reactions studied included those with fluorenone, acetone, styrene, phenylacetylene, acetonitrile, t-butylcyanide, methyl isocyanate, phenyl azide, and azobenzene. Product analyses suggest that aside from addition reactions tetramethylsilacyclopropene can react either via a radical chain polymerization or an anionic chain polymerization mechanism with the latter being the more prevalent. Other reactions studied included the photolysis of tetramethylsilacyclopropene and its reactions in the presence of Pd(PPh/sub 3/)/sub 2/Cl/sub 2/. An appendix includes a study of trimethylsilyl radical disproportionation in the liquid phase to a sila olefin. Trimethylsilyl radicals in solution undergo disproportionation as well as recombination in a 1:5 ratio. The sila olefin formed by disproportionation was trapped by alcohols.

Cornett, B.J.

1980-05-01T23:59:59.000Z

193

U.S. Department of Energy Office of Nuclear Energy, Science and Technology  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

One the cover: One the cover: Albert Einstein (1879-1955) U.S. Department of Energy Office of Nuclear Energy, Science and Technology Washington, D.C. 20585 The History of Nuclear Energy Table of Contents Preface ................................................................... 1 Introduction .......................................................... 3 The Discovery of Fission ...................................... 4 The First Self-Sustaining Chain Reaction ............ 5 The Development of Nuclear Energy for Peaceful Applications ..................................... 7 Chronology of Nuclear Research and Development, 1942-1994 .................................... 13 Selected References ............................................. 23 Glossary ..............................................................

194

Decay Properties of {sup 266}Bh and {sup 262}Db Produced in the {sup 248}Cm+{sup 23}Na Reaction - Further Confirmation of the {sup 278}113 Decay Chain  

SciTech Connect

Decay properties of an isotope {sup 266}Bh and its daughter nucleus {sup 262}Db produced by the {sup 248}Cm({sup 23}Na,5n) reaction were studied by using a gas-filled recoil separator coupled with a position-sensitive semiconductor detector. {sup 266}Bh was clearly identified from the correlation of the known nuclide, {sup 262}Db. The obtained decay properties of {sup 266}Bh and {sup 262}Db are consistent with those observed in the {sup 278}113 chain by RIKEN collaboration, which provided further confirmation of the discovery of {sup 278}113.

Morita, K.; Morimoto, K.; Kaji, D.; Haba, H.; Ozeki, K.; Kudou, Y.; Yoneda, A.; Ichikawa, T.; Katori, K.; Yoshida, A. [RIKEN Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan); Sato, N. [RIKEN Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan); Department of Physics, Tohoku University, Aoba-ku, Sendai 980-8578 (Japan); Sumita, T. [RIKEN Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan); Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510 (Japan); Fujimori, Y.; Tokanai, F. [Department of Physics, Yamagata University, Yamagata 990-8560 (Japan); Goto, S. [Center for Instrumental Analysis, Niigata University, Ikarashi, Nishi-ku, Niigata 950-2181 (Japan); Ideguchi, E. [Center for Nuclear Study, University of Tokyo, Wako, Saitama 351-0198 (Japan); Kasamatsu, Y.; Koura, H.; Tsukada, K. [Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Komori, Y. [Department of Chemistry, Osaka University, Toyonaka, Osaka 560-0043 (Japan)

2010-06-01T23:59:59.000Z

195

Activation cross-sections of long lived products of deuteron induced nuclear reactions on dysprosium up to 50 MeV  

E-Print Network (OSTI)

Activation cross-sections for production of 162m,161,155Ho,165,159,157,155Dy and 161,160,156,155Tb radionuclides in deuteron induced nuclear reactions on elemental dysprosium were measured up to 50 MeV for practical application and the test of the predictive power of nuclear reaction model codes. A stacked-foil irradiation technique and off-line gamma-ray spectrometry were used to determine the activities. No earlier cross-section data were found in the literature. The experimental data are compared with the predictions of the ALICE-D, EMPIRE-D and TALYS codes. Integral production yields were calculated from the fitted experimental data.

F. Tárkányi; F. Ditrói; S. Takács; J. Csikai; A. Hermanne; A. V. Ignatyuk

2014-02-05T23:59:59.000Z

196

Dynamics of low-energy nuclear forces for electromagnetic and weak reactions with the deuteron in the Nambu-Jona-Lasinio model of light nuclei  

E-Print Network (OSTI)

A dynamics of low-energy nuclear forces is investigated for low-energy electromagnetic and weak nuclear reactions with the deuteron in the Nambu-Jona-Lasinio model of light nuclei by example of the neutron-proton radiative capture (M1-capture) n + p -> D + photon, the photomagnetic disintegration of the deuteron photon + D -> n + p and weak reactions of astrophysical interest. These are the solar proton burning p + p -> D + positron + nu_e, the pep-process p + electron + p -> D + nu_e and the neutrino and anti-neutrino disintegration of the deuteron caused by charged nu_e + D -> electron + p + p, anti-nu_e + D -> positron + n + n and neutral nu_e(anti-nu_e) + D -> nu_e(ant-nu_e) + n + p weak currents.

A. N. Ivanov; H. Oberhummer; N. I. Troitskaya; M. Faber

2000-06-22T23:59:59.000Z

197

Determination of the cross sections of (n,2n), (n,gamma) nuclear reactions on germanium isotopes at the energy of neutrons 13.96 MeV  

E-Print Network (OSTI)

The cross sections of 70Ge(n,2n)69Ge, 72Ge(n,2n)71Ge, 76Ge(n,gamma)77(g+0.21m)Ge, 76Ge(n,2n)75Ge nuclear reactions were measured at the energy of neutrons 13.96(6) MeV by activation method with gamma-ray and X-ray spectra studies.

S. V. Begun; O. G. Druzheruchenko; O. O. Pupirina; V. K. Tarakanov

2007-01-23T23:59:59.000Z

198

PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON NUCLEAR PHYSICS  

E-Print Network (OSTI)

STRUCTURE OF NUCLEAR REACTION INDUCED BY LOW ENERGY DEUTERONin the nuclear reaction induced by low energy deuteron on

Saxon, D.S.

2010-01-01T23:59:59.000Z

199

Nuclear magnetic resonance solution structure of hirudin(1–51) and comparison with corresponding three-dimensional structures determined using the complete 65-residue hirudin polypeptide chain  

Science Journals Connector (OSTI)

The three-dimensional structure of the N-terminal 51-residue domain of recombinant hirudin in aqueous solution was determined by 1H nuclear magnetic resonance (NMR) spectroscopy, and the resulting high-quality solution structure was compared with corresponding structures obtained from studies with the intact, 65-residue polypeptide chain of hirudin. On the basis of 580 distance constraints derived from nuclear Overhauser effects and 109 dihedral angle constraints, a group of 20 conformers representing the solution structure of hirudin(1–51) was computed with the program DIANA and energyminimized with a modified version of the program AMBER. Residues 3 to 30 and 37 to 48 form a well-defined molecular core with two antiparallel ?-sheets composed of residues 14 to 16 and 20 to 22, and 27 to 31 and 36 to 40, and three reverse turns at residues 8 to 11 (type II), 17 to 20 (type II?) and 23 to 26 (type II). The average root-mean-square deviation of the individual NMR conformers relative to their mean co-ordinates is 0.38 Å for the backbone atoms and 0.77 Å for all heavy atoms of these residues. Increased structural disorder was found for the N-terminal dipeptide segment, the loop at residues 31 to 36, and the C-terminal tripeptide segment. The solution structure of hirudin(1–51) has the same molecular architecture as the corresponding polypeptide segment in natural hirudin and recombinant desulfatohirudin. It is also closely similar to the crystal structure of the N-terminal 51-residue segment of hirudin in a hirudin-thrombin complex, with root-mean-square deviations of the crystal structure relative to the mean solution structure of 0.61 Å for the backbone atoms and 0.91 Å for all heavy atoms of residues 3 to 30 and 37 to 48. Further coincidence is found for the loop formed by residues 31 to 36, which shows increased structural disorder in all available solution structures of hirudin, and of which residues 32 to 35 are not observable in the electron density map of the thrombin complex. Significant local structural differences between hirudin(1–51) in solution and hirudin in the crystalline thrombin complex were identified mainly for the N-terminal tripeptide segment and residues 17 to 21. These are further analyzed in an accompanying paper.

T. Szyperski; P. Güntert; S.R. Stone; K. Wüthrich

1992-01-01T23:59:59.000Z

200

CP-1: the Past, Present & Future of Nuclear Energy  

NLE Websites -- All DOE Office Websites (Extended Search)

CP-1: the Past, Present & Future of Nuclear Energy CP-1: the Past, Present & Future of Nuclear Energy Director's Welcome Organization Achievements Highlights Fact Sheets, Brochures & Other Documents Multimedia Library About Nuclear Energy Nuclear Reactors Designed by Argonne Argonne's Nuclear Science and Technology Legacy Opportunities within NE Division Visit Argonne Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Celebrating the 70th Anniversary of Chicago Pile 1 (CP-1) Argonne OutLoud on Nuclear Energy Argonne Energy Showcase 2012 Highlights Bookmark and Share CP-1: the Past, Present & Future of Nuclear Energy Jan. 29, 2013 On January 25, 2013, a lunch program to commemorate the 70th anniversary of the world's first self-sustaining, controlled nuclear chain reaction was

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Nuclear structure of {sup 10}B studied with (e,e{prime}), ({pi},{pi}{prime}) and ({gamma},{pi}) reactions  

SciTech Connect

The authors studied nuclear structure of {sup 10}B using (e,e{prime}),({pi},{pi}{prime}) and ({gamma},{pi}) reactions under the distorted wave impulse approximation (DWIA). For this purpose the off-shell dependence of the amplitude was taken into account in the momentum space DWIA. They used the off-shell elementary amplitude of ({pi},{pi}) and ({gamma},{pi}) by the model of Nozawa, Blankleider and Lee. The first order core polarization effects were incorporated with the p-shell wave functions of Cohen and Kurath and Hauge and Maripuu. It was shown that the core-polarization effects greatly improve the agreement with the experimental data and that the simultaneous study of these reactions is useful to probe the spin structure of p-shell nuclei.

Sato, T.; Odagawa, N.; Ohtsubo, H. [Osaka Univ., Toyonaka (Japan). Dept. of Physics; Lee, T.S.H. [Argonne National Lab., IL (United States)

1994-05-01T23:59:59.000Z

202

Behavior of the Cross Sections for Polonium Production in Nuclear Reactions of Ar40 with Dy104  

Science Journals Connector (OSTI)

Excitation functions are reported for the reactions of Dy164 with Ar40 to produce Po200 and Po199. The cross sections are much smaller than the calculated values and it is concluded that this is due to an angular momentum cutoff and to a large fission width. The reaction threshold at a laboratory energy of 4.2 MeV per nucleon indicates a low Coulomb barrier (r0=1.45 fm).

Y. Le Beyec; M. Lefort; A. Vigny

1971-03-01T23:59:59.000Z

203

Weak reactions with light nuclei - 6He beta-decay as a test case for the nuclear weak current  

E-Print Network (OSTI)

We present a microscopic calculation of the 6He beta-decay into the ground state of 6Li. To this end we use the impulse approximation to describe the nuclear weak current. The ground state wave functions are obtained from the solution of the nuclear 6-body problem. The nucleonnucleon interaction is described via the J-matrix inverse scattering potential (JISP), and the nuclear problem is solved using the hyperspherical-harmonics approach. This approach results in numerical accuracy of about 2 per mil in the transition matrix element. Bearing in mind that the contribution of meson-exchange currents to the transition matrix element is about 5%, these results pave the way for accurate estimation of their effect.

Doron Gazit; Sergey Vaintraub; Nir Barnea

2009-01-18T23:59:59.000Z

204

Nuclear reactions of medium and heavy target nuclei with high-energy particles IV. Interpretation of mass fragment yields  

Science Journals Connector (OSTI)

Target residue mass distributions in 3·65 A GeV12C-ion- and 3·65 GeV proton-induced reactions on medium and heavy target nuclei have been interpreted in the theoretical framework of the intranuclear cascade and a...

P. Kozma; K. Hänssgen

1990-06-01T23:59:59.000Z

205

Spallation process with simultaneous multi-particle emission in nuclear evaporation  

SciTech Connect

High energy probes have been used currently to explore nuclear reaction mechanism and nuclear structure. The spallation process governs the reaction process around 1 GeV energy regime. A new aspect introduced here to describe the nuclear reaction is the in-medium nucleonnucleon collision framework. The nucleon-nucleon scattering is kinematically treated by using an effective mass to represent the nuclear binding. In respect to the evaporation phase of the reaction, we introduce the simultaneous particles emission decay. This process becomes important due to the rise of new channels at high excitation energy regime of the compound nucleus. As results, the particles yields in the rapid and evaporation phases are obtained and compared to experimental data. The effect and relevance of these simultaneous emission processes in the evaporation chain is also discussed.

Santos, B. M. [Instituto de Fisica/UFF - Av. Gal. Milton Tavares de Souza, Praia Vermelha, Niteroi - RJ (Brazil); Goncalves, M. [Comissao Nacional de Energia Nuclear/CNEN - Rua Gal Severiano, nr. 90, Botafogo - RJ (Brazil); Assis, L. P. G. de; Duarte, S. B. [Centro Brasileiro de Pesquisas Fisicas/CBPF - Rua Dr. Xavier Sigaud, nr.150, Urca - RJ (Brazil)

2013-05-06T23:59:59.000Z

206

Method of controlling fusion reaction rates  

DOE Patents (OSTI)

This invention relates to a method of controlling the reaction rates in a nuclear fusion reactor; and more particularly, to the use of polarized nuclear fuel.

Kulsrud, R.M.; Furth, H.P.; Valeo, E.J.; Goldhaber, M.

1983-05-09T23:59:59.000Z

207

National Nuclear Data Center  

NLE Websites -- All DOE Office Websites (Extended Search)

Internal Radiation Dose Evaluated Nuclear (reaction) Data File Experimental nuclear reaction data Sigma Retrieval & Plotting Nuclear structure & decay Data Nuclear Science References Experimental Unevaluated Nuclear Data List Evaluated Nuclear Structure Data File NNDC databases Ground and isomeric states properties Nuclear structure & decay data journal Nuclear reaction model code Tools and Publications US Nuclear Data Program Cross Section Evaluation Working Group Nuclear data networks Basic properties of atomic nuclei Parameters & thermal values Basic properties of atomic nuclei Internal Radiation Dose Evaluated Nuclear (reaction) Data File Experimental nuclear reaction data Sigma Retrieval & Plotting Nuclear structure & decay Data Nuclear Science References Experimental Unevaluated Nuclear Data List Evaluated Nuclear Structure Data File NNDC databases Ground and isomeric states properties Nuclear structure & decay data journal Nuclear reaction model code Tools and Publications US Nuclear Data Program Cross Section Evaluation Working Group Nuclear data networks Basic properties of atomic nuclei Parameters & thermal values Basic properties of atomic nuclei Homepage BNL Home Site Index - Go USDNP and CSEWG November 18-22! USNDP CSEWG Agenda Thanks for attending! EXFOR 20,000 Milestone EXFOR Milestone 20,000 experimental works are now in the EXFOR database!

208

Search for anomalous fragments in 1.8A-GeV Ar40 reactions in nuclear emulsions  

Science Journals Connector (OSTI)

Results are presented from an investigation of the mean free path in nuclear emulsion of multiply charged fragments, produced by 1.8A-GeV argon nuclei. Charge identification of 6965 fragments with charges Z?2, producing 2192 secondary interactions, has been made. No dependence of the mean free path on the distance from the preceding collision is observed and thus our result is consistent with the nonexistence of anomalons.

R. Bhanja et al.

1985-02-25T23:59:59.000Z

209

Extended sum-rule model view of light and intermediate mass fragment emission in nuclear reactions at intermediate energies  

Science Journals Connector (OSTI)

The original sum-rule model worked out by Wilczy?ski et al. and successfully used for a global description of complete and incomplete fusion reactions has been extended by a term accounting for dissipative processes of the dinuclear system on its way to fusion. When applying to light- and heavy-ion collisions with various targets at energies in the transitional region, the new term proves to be rather essential for reproducing the element distributions of the fragments emitted from rather asymmetric systems.

I. M. Brncu?; H. Rebel; J. Wentz; V. Corcalciuc

1990-11-01T23:59:59.000Z

210

Nuclear transparency and effective kaon-nucleon cross section from the A(e, e'K+) reaction  

E-Print Network (OSTI)

We have determined the transparency of the nuclear medium to kaons from $A(e,e^{'} K^{+})$ measurements on $^{12}$C, $^{63}$Cu, and $^{197}$Au targets. The measurements were performed at the Jefferson Laboratory and span a range in four-momentum-transfer squared Q$^2$=1.1 -- 3.0 GeV$^2$. The nuclear transparency was defined as the ratio of measured kaon electroproduction cross sections with respect to deuterium, ($\\sigma^{A}/\\sigma^{D}$). We further extracted the atomic number ($A$) dependence of the transparency as parametrized by $T= (A/2)^{\\alpha-1}$ and, within a simple model assumption, the in-medium effective kaon-nucleon cross sections. The effective cross sections extracted from the electroproduction data are found to be smaller than the free cross sections determined from kaon-nucleon scattering experiments, and the parameter $\\alpha$ was found to be significantly larger than those obtained from kaon-nucleus scattering. We have included similar comparisons between pion- and proton-nucleon effective cross sections as determined from electron scattering experiments, and pion-nucleus and proton-nucleus scattering data.

Nuruzzaman; D. Dutta; J. Arrington; R. Asaturyan; F. Benmokhtar; W. Boeglin; P. Bosted; A. Bruell; B. Clasie; M. E. Christy; E. Chudakov; M. M. Dalton; A. Daniel; D. Day; L. El Fassi; R. Ent; H. C. Fenker; J. Ferrer; N. Fomin; H. Gao; K. Garrow; D. Gaskel; C. Gray; T. Horn; G. M. Huber; M. K. Jones; N. Kalantarians; C. E. Keppel; K. Kramer; Y. Li; Y. Liang; A. F. Lung; S. Malace; P. Markowitz; A. Matsumura; D. G. Meekins; T. Mertens; T. Miyoshi; H. Mkrtchyan; R. Monson; T. Navasardyan; G. Niculescu; I. Niculescu; Y. Okayasu; A. K. Opper; C. Perdrisat; V. Punjabi; X. Qian; A. W. Rauf; V. M. Rodriquez; D. Rohe; J. Seely; E. Segbefia; G. R. Smith; M. Sumihama; V. Tadevosyan; L. Tang; V. Tvaskis; W. F. Vulcan; F. R. Wesselmann; S. A. Wood; L. Yuan; X. C. Zheng

2011-08-02T23:59:59.000Z

211

Comparison of two analysis methods for nuclear reaction measurements of 12C +12C interactions at 95 MeV/u for hadrontherapy  

E-Print Network (OSTI)

During therapeutic treatment with heavier ions like carbon, the beam undergoes nuclear fragmentation and secondary light charged particles, in particular protons and alpha particles, are produced. To estimate the dose deposited into the tumors and the surrounding healthy tissues, the accuracy must be higher than ($\\pm$3% and$\\pm$1 mm). Therefore, measurements are performed to determine the double differential cross section for different reactions. In this paper, the analysis of data from 12C +12C reactions at 95 MeV/u are presented. The emitted particles are detected with \\DeltaEthin-\\DeltaEthick-E telescopes made of a stack of two silicon detectors and a CsI crystal. Two different methods are used to identify the particles. One is based on graphical cuts onto the \\DeltaE-E maps, the second is based on the so-called KaliVeda method using a functional description of \\DeltaE versus E. The results of the two methods will be presented in this paper as well as the comparison between both.

J. Dudouet; D. Juliani; M. Labalme; J. C. Angélique; B. Braunn; J. Colin; D. Cussol; Ch. Finck; J. M. Fontbonne; H. Guérin; P. Henriquet; J. Krimmer; M. Rousseau; M. G. Saint-Laurent

2013-03-31T23:59:59.000Z

212

Triggered amplification by hybridization chain reaction  

E-Print Network (OSTI)

­23) driven by the free energy of base pair formation. Synthetic DNA machines can be powered by strand

Pierce, Niles A.

213

Nuclear Physics for Nuclear Fusion  

SciTech Connect

The nuclear fusion data for deuteron-triton resonance near 100 keV are found to be consistent with the selective resonant tunneling model. The feature of this selective resonant tunneling is the selectivity. It selects not only the energy level, but also the damping rate (nuclear reaction rate). When the Coulomb barrier is thin and low, the resonance selects the fast reaction channel; however, when the Coulomb barrier is thick and high, the resonance selects the slow reaction channel. This mechanism might open an approach toward fusion energy with no strong nuclear radiation.

Li Xingzhong [Tsinghua University (China)

2002-01-15T23:59:59.000Z

214

Features of a subcritical nuclear reactor  

Science Journals Connector (OSTI)

Abstract A subcritical nuclear reactor is a device where the nuclear-fission chain reaction is initiated and maintained using an external neutron source. It is a valuable educational and research tool where in a safe way many reactor parameters can be measured. Here, we have used the six-factor formula to calculate the effective multiplication factor of a subcritical nuclear reactor Nuclear Chicago model 9000. Using the MCNP5 code, a three-dimensional model of the subcritical reactor was developed to estimate the effective multiplication factor, the neutron spectra, and the total and thermal neutron fluences along the radial and axial axis. The MCNP5 results of the effective multiplication factor were compared with those obtained from the six-factor formula. The effective dose and the Ambient dose equivalent, at three sites outside the reactor, were estimated; the Ambient dose equivalent was also measured and compared with the calculated values.

Hector Rene Vega-Carrillo; Isvi Ruben Esparza-Garcia; Alvaro Sanchez

2015-01-01T23:59:59.000Z

215

Nuclear reactions of medium and heavy target nuclei with high-energy projectiles II. Fragmentation ofnatAg and197Au by 3.65 AGeV12C-ions and 3.65 GeV protons  

Science Journals Connector (OSTI)

The cross sections of a number of target fragmentation products formed in nuclear reactions of 3·65 A GeV12C-ions and 3·65 GeV protons withnatAg and197Au have been measured. The measurements have been done by dir...

P. Kozma; C. Damdinsuren

1990-01-01T23:59:59.000Z

216

Sleeve reaction chamber system  

DOE Patents (OSTI)

A chemical reaction chamber system that combines devices such as doped polysilicon for heating, bulk silicon for convective cooling, and thermoelectric (TE) coolers to augment the heating and cooling rates of the reaction chamber or chambers. In addition the system includes non-silicon-based reaction chambers such as any high thermal conductivity material used in combination with a thermoelectric cooling mechanism (i.e., Peltier device). The heat contained in the thermally conductive part of the system can be used/reused to heat the device, thereby conserving energy and expediting the heating/cooling rates. The system combines a micromachined silicon reaction chamber, for example, with an additional module/device for augmented heating/cooling using the Peltier effect. This additional module is particularly useful in extreme environments (very hot or extremely cold) where augmented heating/cooling would be useful to speed up the thermal cycling rates. The chemical reaction chamber system has various applications for synthesis or processing of organic, inorganic, or biochemical reactions, including the polymerase chain reaction (PCR) and/or other DNA reactions, such as the ligase chain reaction.

Northrup, M. Allen (Berkeley, CA); Beeman, Barton V. (San Mateo, CA); Benett, William J. (Livermore, CA); Hadley, Dean R. (Manteca, CA); Landre, Phoebe (Livermore, CA); Lehew, Stacy L. (Livermore, CA); Krulevitch, Peter A. (Pleasanton, CA)

2009-08-25T23:59:59.000Z

217

Nuclear viscosity  

Science Journals Connector (OSTI)

The decay rate of momentum in a nuclear reaction is given by an exact formula expressed in terms of the T matrix. A special case, where a viscosity coefficient can be estimated, is considered.

B. Giraud; J. Le Tourneux; E. Osnes

1975-01-01T23:59:59.000Z

218

I. Nuclear Production Reaction and Chemical Isolation Procedure for 240Am II. New Superheavy Element Isotopes: 242Pu(48Ca,5n)285-114  

E-Print Network (OSTI)

of superheavy nuclei in cold fusion reactions. Phys. Rev. C,transfermium elements in cold fusion reactions. Phys. Rev.have been deemed “cold fusion” reactions because of the low

Ellison, Paul Andrew

2011-01-01T23:59:59.000Z

219

Nuclear Data Program - Nuclear Engineering Division (Argonne)  

NLE Websites -- All DOE Office Websites (Extended Search)

Data Program Data Program Nuclear Data Program Overview Current Projects & Recent Activities Collaborating Organizations Publications Nuclear Data Measurements (NDM) Reports Experimental Nuclear Data Resources Contact ND Program Related Resources Other Major Programs Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE Division on Flickr Nuclear Data Program We contribute to the development of comprehensive nuclear reactions and nuclear structure databases, including nuclear data measurement, analysis, modeling and evaluation methodologies, that are implemented in basic science research and advanced nuclear technologies. Bookmark and Share Recent Events Nuclear Structure 2012 Conference Argonne National Laboratory hosted the

220

Absolute nuclear material assay  

DOE Patents (OSTI)

A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

Prasad, Manoj K. (Pleasanton, CA); Snyderman, Neal J. (Berkeley, CA); Rowland, Mark S. (Alamo, CA)

2012-05-15T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Nuclear Processes at Solar Energy  

E-Print Network (OSTI)

LUNA, Laboratory for Underground Nuclear Astrophysics at Gran Sasso, is measuring fusion cross sections down to the energy of the nucleosynthesis inside stars. Outstanding results obtained up to now are the cross-section measurements within the Gamow peak of the Sun of $^{3}He(^{3}He,2p)^{4}He$ and the $D(p,\\gamma)^{3}He$. The former plays a big role in the proton-proton chain, largely affecting the calculated solar neutrino luminosity, whereas the latter is the reaction that rules the proto-star life during the pre-main sequence phase. The implications of such measurements will be discussed. Preliminary results obtained last year on the study of $^{14}N(p,\\gamma)^{15}O$, the slowest reaction of the CNO cycle, will also be shown.

Carlo Broggini

2003-08-29T23:59:59.000Z

222

I. Nuclear Production Reaction and Chemical Isolation Procedure for 240Am II. New Superheavy Element Isotopes: 242Pu(48Ca,5n)285-114  

E-Print Network (OSTI)

Nuclear Security Administration (NNSA) Stewardship Science Academic Alliances Program (SSAAP). This program funds academic research

Ellison, Paul Andrew

2011-01-01T23:59:59.000Z

223

Energy requirements for nuclear transformations  

Science Journals Connector (OSTI)

Energy requirements for nuclear transformations ... There are several conservation requirements that must be met in nuclear reactions, including the conservation of energy (E = mc2), charge, angular and linear momentum. ... Nuclear / Radiochemistry ...

Benjamin Carrol; Peter F. E. Marapodi

1951-01-01T23:59:59.000Z

224

Nuclear Energy Production  

Science Journals Connector (OSTI)

We shall limit ourselves here to a very rough summary of the most important features of nuclear reactions in stars. This will suffice completely ... , while the study of particular aspects of nuclear astrophysics...

Professor Dr. Rudolf Kippenhahn…

1990-01-01T23:59:59.000Z

225

Nuclear Science--A Guide to the Nuclear Science Wall Chart 2003 Contemporary Physics Education Project (CPEP)  

E-Print Network (OSTI)

Nuclear Science--A Guide to the Nuclear Science Wall Chart ©2003 Contemporary Physics Education Project (CPEP) 7-1 Chapter 7 Nuclear Reactions Nuclear reactions and nuclear scattering are used, protons, alphas, or "heavy ions"), creates these reactions when they strike a target nucleus. Nuclear

226

Nuclear Reactions and Reactor Safety  

E-Print Network (OSTI)

. Snoeijer 85 On the drag of turbulent vortex rings L. Gan, J. R. Dawson & T. B. Nickels 106 Subcritical Linear water waves: the horizontal motion of a structure in the time domain P. McIver 313 Transmission

Onuchic, José

227

Record of Cycling Operation of the Natural Nuclear Reactor in the Oklo/Okelobondo Area in Gabon  

Science Journals Connector (OSTI)

Using selective laser extraction technique combined with sensitive ion-counting mass spectrometry, we have analyzed the isotopic structure of fission noble gases in U-free La-Ce-Sr-Ca aluminous hydroxy phosphate associated with the 2 billion yr old Oklo natural nuclear reactor. In addition to elevated abundances of fission-produced Zr, Ce, and Sr, we discovered high (up to 0.03??cm3???STP/g) concentrations of fission Xe and Kr, the largest ever observed in any natural material. The specific isotopic structure of xenon in this mineral defines a cycling operation for the reactor with 30-min active pulses separated by 2.5 h dormant periods. Thus, nature not only created conditions for self-sustained nuclear chain reactions, but also provided clues on how to retain nuclear wastes, including fission Xe and Kr, and prevent uncontrolled runaway chain reaction.

A. P. Meshik; C. M. Hohenberg; O. V. Pravdivtseva

2004-10-27T23:59:59.000Z

228

NUCLEAR CHEMISTRY DIV. ANNUAL REPORT 1980-81  

E-Print Network (OSTI)

1. Research Programs Exotic Nuclei and Nuclear Reactions J.1. RESEARCH PROGRAMS Exotic Nuclei and Nuclear Reactionsnuclei. Complementary research programs in light-ion nuclear

Cerny, J.

2010-01-01T23:59:59.000Z

229

Linear chain magnetism  

Science Journals Connector (OSTI)

Linear chain magnetism ... A brief introduction to this concept, which is also called lower dimensional magnetism. ...

Richard L. Carlin

1991-01-01T23:59:59.000Z

230

Magnetic moments of long isotopic chains  

E-Print Network (OSTI)

Dipole magnetic moments of several long isotopic chains are analyzed within the self-consistent Finite Fermi System theory based on the Generalized Energy Density Functional method with exact account for the pairing and quasi-particle continuum. New data for nuclei far from the beta-stability valley are included in the analysis. For a number of semi-magic isotopes of the tin and lead chains a good description of the data is obtained, with accuracy of 0.1 - 0.2 mu_N. A chain of non-magic isotopes of copper is also analyzed in detail. It is found that the systematic analysis of magnetic moments of this long chain yields rich information on the evolution of the nuclear structure of the Cu isotopes. In particular, it may give a signal of deformation for the ground state of some nuclei in the chain.

I. N. Borzov; E. E. Saperstein; S. V. Tolokonnikov; G. Neyens; N. Severijns

2008-04-28T23:59:59.000Z

231

A classical approach in simple nuclear fusion reaction {sub 1}H{sup 2}+{sub 1}H{sup 3} using two-dimension granular molecular dynamics model  

SciTech Connect

Molecular dynamics in 2-D accompanied by granular model provides an opportunity to investigate binding between nuclei particles and its properties that arises during collision in a fusion reaction. A fully classical approach is used to observe the influence of initial angle of nucleus orientation to the product yielded by the reaction. As an example, a simplest fusion reaction between {sub 1}H{sup 2} and {sub 1}H{sup 3} is observed. Several products of the fusion reaction have been obtained, even the unreported ones, including temporary {sub 2}He{sup 4} nucleus.

Viridi, S.; Kurniadi, R.; Waris, A.; Perkasa, Y. S. [Nuclear Physics and Biophysics Research Division, Institut Teknologi Bandung, Bandung 40132 (Indonesia); Doctoral Program in Physics, Institut Teknologi Bandung, Bandung 40132 Physics Department, Universitas Islam Negeri Sunan Gunung Djati, Bandung 40614 (Indonesia)

2012-06-06T23:59:59.000Z

232

The nuclear fusion for the reactions2H(d, n)3He,2H(d, p)3H,3H(d, n)4He  

Science Journals Connector (OSTI)

In the present paper the elastic model for the subbarrier fusion is applied to the reactions2H(d, n)3He,2H(d, p)3H,3H(d, n)4He. A comparison between the values of the reaction rates obtained in the framework of t...

A. Scalia

1989-05-01T23:59:59.000Z

233

Silicon-based sleeve devices for chemical reactions  

DOE Patents (OSTI)

A silicon-based sleeve type chemical reaction chamber that combines heaters, such as doped polysilicon for heating, and bulk silicon for convection cooling. The reaction chamber combines a critical ratio of silicon and silicon nitride to the volume of material to be heated (e.g., a liquid) in order to provide uniform heating, yet low power requirements. The reaction chamber will also allow the introduction of a secondary tube (e.g., plastic) into the reaction sleeve that contains the reaction mixture thereby alleviating any potential materials incompatibility issues. The reaction chamber may be utilized in any chemical reaction system for synthesis or processing of organic, inorganic, or biochemical reactions, such as the polymerase chain reaction (PCR) and/or other DNA reactions, such as the ligase chain reaction, which are examples of a synthetic, thermal-cycling-based reaction. The reaction chamber may also be used in synthesis instruments, particularly those for DNA amplification and synthesis.

Northrup, M. Allen (Berkeley, CA); Mariella, Jr., Raymond P. (Danville, CA); Carrano, Anthony V. (Livermore, CA); Balch, Joseph W. (Livermore, CA)

1996-01-01T23:59:59.000Z

234

Nuclear condensation  

Science Journals Connector (OSTI)

This work draws an analogy between a heated nucleus breaking up into clusters and a liquid undergoing a phase transition to a gas in which droplets appear. The critical temperature and density in the nucleus are investigated using a Skyrme effective interaction and finite temperature Hartree-Fock theory. The energy and pressure as a function of density are calculated. The effects of compressibility, effective mass, and binding energy per particle on the critical temperature and critical density of nuclear systems is developed. In some cases, analytic expressions for these quantities can be obtained.NUCLEAR REACTIONS Phase transitions in hot nuclear matter.

H. Jaqaman; A. Z. Mekjian; L. Zamick

1983-06-01T23:59:59.000Z

235

Nuclear evaporation process with simultaneous multiparticle emission  

E-Print Network (OSTI)

The nuclear evaporation process is reformulated by taking into account simultaneous multiparticle emission from a hot compound nucleus appearing as an intermediate state in many nuclear reaction mechanisms. The simultaneous emission of many particles is particularly relevant for high excitation energy of the compound nucleus.These channels are effectively open in competition with the single particle emissions and fission in this energy regime. Indeed, the inclusion of these channels along the decay evaporating chain shows that the yield of charged particles and occurrence of fission are affected by these multiparticle emission processes of the compounded nucleus, when compared to the single sequential emission results. The effect also shows a qualitative change in the neutron multiplicity of different heavy compound nucleus considered. This should be an important aspect for the study of spallation reaction in Acceleration Driven System (ADS) reactors. The majority of neutrons generated in these reactions come from the evaporation stage of the reaction, the source of neutron for the system. A Monte Carlo simulation is employed to determine the effect of these channels on the particle yield and fission process. The relevance of the simultaneous particle emission with the increasing of excitation energy of the compound nucleus is explicitly shown.

Leonardo P. G. De Assis; Sergio B. Duarte; Bianca M. Santos

2012-08-07T23:59:59.000Z

236

Nuclear Astrophysics  

E-Print Network (OSTI)

Nuclear physics has a long and productive history of application to astrophysics which continues today. Advances in the accuracy and breadth of astrophysical data and theory drive the need for better experimental and theoretical understanding of the underlying nuclear physics. This paper will review some of the scenarios where nuclear physics plays an important role, including Big Bang Nucleosynthesis, neutrino production by our sun, nucleosynthesis in novae, the creation of elements heavier than iron, and neutron stars. Big-bang nucleosynthesis is concerned with the formation of elements with A nuclear physics inputs required are few-nucleon reaction cross sections. The nucleosynthesis of heavier elements involves a variety of proton-, alpha-, neutron-, and photon-induced reactions, coupled with radioactive decay. The advent of radioactive ion beam facilities has opened an important new avenue for studying these processes, as many involve radioactive species. Nuclear physics also plays an important role in neutron stars: both the nuclear equation of state and cooling processes involving neutrino emission play a very important role. Recent developments and also the interplay between nuclear physics and astrophysics will be highlighted.

Carl R. Brune

2005-02-28T23:59:59.000Z

237

The U.S. Nuclear Data Network: Summary of the twenty-first meeting  

SciTech Connect

The following progress reports and related documents from the members of the US Nuclear Data Network (USNDN) are included at attachments: INEL Decay Data and Mass-chain Evaluation Project; Decay-data Evaluation Project; Isotopes Project Report; Report on High-spin Data Evaluations; The NNDC Activity Report, Parts A and B; Nuclear Science References (NSR) Task Force Report; Status of Mass Chains A = 1 to 266; Nuclear Data Project Activity Report; and TUNL Nuclear Data Evaluation Project Report; The progress report of the Center for Nuclear Information Technology; An Overview of the USNDN; Evaluated Nuclear Structure Data File-Status; Report on High-spin Evaluations for ENSDF since November 1994; The High-spin Data and the Workshop on Data Analysis; Decay Data Evaluation Project; Compilation of High Energy Heavy-ion and Electron Interaction Data; Dissemination/code development update; 8th Edition of the Table of Isotopes/VuENSDF; Bits of Power-Issues in the Transborder Flow of Scientific and Technical Data; Data activities at the Center for Nuclear Information Technology (CNIT), San Jose State University; The Agenda and the Minutes of the Formats and Procedures Subcommittee of the NSDD; A status report on the US Nuclear Reaction Data Network (USNRDN); Coordination/Cooperation and Communication as applied to the USNDN; Nuclear Structure Data Evaluations: Issues/Concerns; Electronic Publishing of Nuclear Data; The status of the Nuclear Astrophysics Data Project; and Nuclear Astrophysics Data needs for A=3-20/Possible contributions by TUNL. The attendees formed the three Discussion Groups. The charge to these Discussion Groups was how to achieve the goal of the USNDN to make the ENSDF and the NSR the best nuclear structure and bibliographic databases available, while maintaining a proper balance between evaluations and data dissemination.

NONE

1996-08-01T23:59:59.000Z

238

Safe Chain Saw Operation.  

E-Print Network (OSTI)

Z TA24S.7 8873 NO.1409 B-1409 SAFE CHAIN SAW OPERATION Gary S. Nelson* A chain saw is a portable power cutting machine. Used properly, it will trim or cut down trees, clear land or cut fireplace wood. Improperly used, a chain saw can... ground level , losing balance, shifting chain saw weight while cutting at or above waist level or ex periencing chain saw kickback. Often, loss of balance causes an operator to reach into the running saw blade as he grabs to steady himself. Other...

Nelson, Gary S.

1982-01-01T23:59:59.000Z

239

Nuclear shell effect and collinear tripartition of nuclei  

E-Print Network (OSTI)

A possibility of formation of the three reaction products having comparable masses at the spontaneous fission of $^{252}$Cf is theoretically explored. This work is aimed to study the mechanism leading to observation of the reaction products with masses $M_1=$136---140 and $M_2=$68---72 in coincidence by the FOBOS group in JINR. The same type of ternary fission decay has been observed in the reaction $^{235}$U(n$_{\\rm th}$,fff). The potential energy surface for the ternary system forming a collinear nuclear chain is calculated for the wide range of mass and charge numbers of constituent nuclei. The results of the PES for the tripartition of $^{252}$Cf(sf,fff) shows, that we have favorable dynamical conditions for the formation of fragments with mass combinations of clusters $^{68-70}$Ni with $^{130-132}$Sn and with missing cluster $^{48-52}$Ca.

Nasirov, A K; Tashkhodjaev, R B

2014-01-01T23:59:59.000Z

240

Reaction kinetics in living systems  

Science Journals Connector (OSTI)

...l/vi) behaves like a resistance in an electric circuit, and vi itself acts...velocity and the velocity for each elementary step in a chain of reactions...where R is the specific resistance, c is the capacity, 4 g9n...

H Eyring; S M Ma; I Ueda

1981-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Nuclear reactions of medium and heavy target nuclei with high-energy projectiles III. Emission of24Na and28Mg fragments  

Science Journals Connector (OSTI)

The emission of24Na and28Mg fragments in the reaction induced by 3·65 A GeV12C-ions and 3·65 GeV protons on Mn, Co, Cu, Ag, Au, and Pb targets has been studied. The experimental ratios of forward-to-backward emis...

P. Kozma

1990-05-01T23:59:59.000Z

242

Polypeptide chain collapse and protein folding Jayant B. Udgaonkar  

E-Print Network (OSTI)

Review Polypeptide chain collapse and protein folding Jayant B. Udgaonkar National Centre is an integral component of a protein folding reaction. In this review, exper- imental characterization solvent [2]. A distinctive physical feature of any protein folding reaction is the greater than 3-fold

243

Microfabricated sleeve devices for chemical reactions  

DOE Patents (OSTI)

A silicon-based sleeve type chemical reaction chamber that combines heaters, such as doped polysilicon for heating, and bulk silicon for convection cooling. The reaction chamber combines a critical ratio of silicon and non-silicon based materials to provide the thermal properties desired. For example, the chamber may combine a critical ratio of silicon and silicon nitride to the volume of material to be heated (e.g., a liquid) in order to provide uniform heating, yet low power requirements. The reaction chamber will also allow the introduction of a secondary tube (e.g., plastic) into the reaction sleeve that contains the reaction mixture thereby alleviating any potential materials incompatibility issues. The reaction chamber may be utilized in any chemical reaction system for synthesis or processing of organic, inorganic, or biochemical reactions, such as the polymerase chain reaction (PCR) and/or other DNA reactions, such as the ligase chain reaction, which are examples of a synthetic, thermal-cycling-based reaction. The reaction chamber may also be used in synthesis instruments, particularly those for DNA amplification and synthesis.

Northrup, M. Allen (Berkeley, CA)

2003-01-01T23:59:59.000Z

244

Ising-Chain Statistics  

Science Journals Connector (OSTI)

The general n-spin correlation function for the Ising chain is calculated exactly. The perpendicular magnetic susceptibility is calculated for arbitrary values of the parallel magnetic field.

James S. Marsh

1966-05-06T23:59:59.000Z

245

Nuclear Science References Coding Manual D.F. Winchell  

E-Print Network (OSTI)

Nuclear Science References Coding Manual D.F. Winchell National Nuclear Data Center Brookhaven and coding procedures for specific topics . . 18 3.2.1 NUCLEAR REACTIONS . . . . . . . . . . . . . . . . 19 3.2.2 RADIOACTIVITY . . . . . . . . . . . . . . . . . . . . 20 3.2.3 NUCLEAR STRUCTURE

Ohta, Shigemi

246

Barloworld Supply Chain Software USA  

E-Print Network (OSTI)

Barloworld Supply Chain Software USA Supply Chain Consultant / Inventory Analyst Position November 2011 #12;Barloworld SCS USA ­ Supply Chain / Inventory Analyst Aug 2011 Page 2 of 4 INTRODUCTION Barloworld Supply Chain Software (SCS) USA would like to invite you to apply for a Supply Chain

Heller, Barbara

247

E-Print Network 3.0 - alpha reactions cross-sections Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

+ Ag reaction for di27;erent cross sections, as a function of time. 12... ; 50 P. Danielewicz Another nuclear stopping observable has been the reaction cross section for...

248

Nuclear Energy  

Science Journals Connector (OSTI)

Nuclear Energy ... A brief summary of the history and key concepts of nuclear energy. ... Nuclear / Radiochemistry ...

Charles D. Mickey

1980-01-01T23:59:59.000Z

249

Nuclear batteries  

Science Journals Connector (OSTI)

Nuclear batteries ... Describes the structure, operation, and application of nuclear batteries. ... Nuclear / Radiochemistry ...

Alfred B. Garrett

1956-01-01T23:59:59.000Z

250

NUCLEAR SCIENCE DIVISION ANNUAL REPORT 1979-1980  

E-Print Network (OSTI)

1. Research Programs Exotic Nuclei and Nuclear Reactions J.1. RESEARCH PROGRAMS. E X O T I C NUCLEI A N D NUCLEAR R E A

Cerny, J.

2010-01-01T23:59:59.000Z

251

Large Scale Computing and Storage Requirements for Nuclear Physics Research  

E-Print Network (OSTI)

Low-Energy Nuclear Physics National Joseph Carlson / HPC Initiative: Building a Universal Joseph Carlson Jonathan Engel Nuclear Energy Density Functional Structure and Reactions

Gerber, Richard A.

2012-01-01T23:59:59.000Z

252

Dynamical cluster-decay model for hot and rotating light-mass nuclear systems, applied to low-energy $^{32}$S + $^{24}$Mg $\\to ^{56}$Ni reaction  

E-Print Network (OSTI)

The dynamical cluster-decay model (DCM) is developed further for the decay of hot and rotating compound nuclei (CN) formed in light heavy-ion reactions. The model is worked out in terms of only one parameter, namely the neck-length parameter, which is related to the total kinetic energy TKE(T) or effective Q-value $Q_{eff}(T)$ at temperature T of the hot CN, defined in terms of the both the light-particles (LP), with $A \\leq$ 4, Z $\\leq$ 2, as well as the complex intermediate mass fragments (IMF), with $4 2$, is considered as the dynamical collective mass motion of preformed clusters through the barrier. Within the same dynamical model treatment, the LPs are shown to have different characteristics as compared to the IMFs. The systematic variation of the LP emission cross section $\\sigma_{LP}$, and IMF emission cross section $\\sigma_{IMF}$, calculated on the present DCM match exactly the statistical fission model predictions. It is for the first time that a non-statistical dynamical description is developed for the emission of light-particles from the hot and rotating CN. The model is applied to the decay of $^{56}$Ni formed in the $^{32}$S + $^{24}$Mg reaction at two incident energies E$_{c.m.}$ = 51.6 and 60.5 MeV. Both the IMFs and average $\\bar{TKE}$ spectra are found to compare reasonably nicely with the experimental data, favoring asymmetric mass distributions. The LPs emission cross section is shown to depend strongly on the type of emitted particles and their multiplicities.

Raj K. Gupta; M. Balasubramaniam; Rajesh Kumar; Dalip Singh; C. Beck; W. Greiner

2004-10-11T23:59:59.000Z

253

European supply chain study  

E-Print Network (OSTI)

Introduction: Supply chain management has been defined as, "..a set of approaches utilized to efficiently integrate suppliers, manufacturers, warehouses and stores, so that merchandise is produced and distributed at the ...

Puri, Mohitkumar

2009-01-01T23:59:59.000Z

254

Nuclear Forensics  

NLE Websites -- All DOE Office Websites (Extended Search)

nuclear forensics Nuclear Forensics AMS is a Powerful Tool for Nuclear Forensics Nuclear forensics, which can be applied to both interdicted materials and debris from a nuclear...

255

Lithium and nuclear fusion  

Science Journals Connector (OSTI)

... the EEC of a decision on the siting of the Joint European Torus (JET) nuclear fusion project, worrying setbacks though these are for European fusion research, should not be allowed ... gain is the highest (about 1,800 per fusion reaction). The first generation of nuclear fusion reactors will therefore need a continuous supply of both deuterium and tritium fuel.

Nick Walton, Ed Spooner

1976-06-17T23:59:59.000Z

256

[Nuclear theory: Annual report  

SciTech Connect

This report discusses topics on : nuclear structure models; algebraic models of hadronic structure; nuclear reactions; hot rotating nuclei; chaos in nuclei; signatures of the quark-gluon plasma; hadronic spectroscopy; octupole collectivity in nuclei; finite-temperature methods for the many-body problem; and classical limit of algebraic hamiltonians. (LSP)

Iachello, F.; Alhassid, Y.; Kusnezov, D.

1991-12-31T23:59:59.000Z

257

(Nuclear theory: Annual report)  

SciTech Connect

This report discusses topics on : nuclear structure models; algebraic models of hadronic structure; nuclear reactions; hot rotating nuclei; chaos in nuclei; signatures of the quark-gluon plasma; hadronic spectroscopy; octupole collectivity in nuclei; finite-temperature methods for the many-body problem; and classical limit of algebraic hamiltonians. (LSP)

Iachello, F.; Alhassid, Y.; Kusnezov, D.

1991-01-01T23:59:59.000Z

258

Nucleonic and Electromagnetic Reaction Cross Sections of Medium and High Energy 11Li Projectiles  

Science Journals Connector (OSTI)

......has the low excitation energy around Ex~10 MeV...effects of Coulomb and nuclear potentials, Fermi motion...experimental results of medium energy and high energy reaction cross sections...Reaction Cross Sections 501 nuclear wave functions. The......

Michio Honma; Hiroyuki Sagawa

1990-09-01T23:59:59.000Z

259

Nuclear rearrangement energy  

Science Journals Connector (OSTI)

The concept of rearrangement energy in nuclear particle removal is carefully defined by specifying several energies associated with the process and its analysis. Connection is made between the present definition and closely related concepts apt to be confused with "rearrangement energy" so defined. Remarks are made concerning the implications of rearrangement to analysis and interpretation of experimental data.NUCLEAR STRUCTURE Nuclear rearrangement energy theoretically defined and differentiated from related energies. Reaction theories examined regarding rearrangement.

William A. Friedman

1975-07-01T23:59:59.000Z

260

Statistical Description of Cluster Emission Including Direct Reactions  

SciTech Connect

The coalescence idea of the Iwamoto-Harada-Bisplinghoff model within the pre-equilibrium (exciton model) approach to nuclear reactions has been generalized and the links to direct reactions have been outlined.

Betak, Emil [Institute of Physics, Slovak Academy of Sciences, 84511 Bratislava (Slovakia); Faculty of Philosophy and Sciences, Silesian University, 74601 Opava (Czech Republic)

2006-04-26T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Theories of Low Energy Nuclear Transmutations  

E-Print Network (OSTI)

Employing concrete examples from nuclear physics it is shown that low energy nuclear reactions can and have been induced by all of the four fundamental interactions (i) (stellar) gravitational, (ii) strong, (iii) electromagnetic and (iv) weak. Differences are highlighted through the great diversity in the rates and similarity through the nature of the nuclear reactions initiated by each.

Y. N. Srivastava; A. Widom; J. Swain

2012-10-27T23:59:59.000Z

262

Nuclear Fabrication Consortium  

SciTech Connect

This report summarizes the activities undertaken by EWI while under contract from the Department of Energy (DOE) � Office of Nuclear Energy (NE) for the management and operation of the Nuclear Fabrication Consortium (NFC). The NFC was established by EWI to independently develop, evaluate, and deploy fabrication approaches and data that support the re-establishment of the U.S. nuclear industry: ensuring that the supply chain will be competitive on a global stage, enabling more cost-effective and reliable nuclear power in a carbon constrained environment. The NFC provided a forum for member original equipment manufactures (OEM), fabricators, manufacturers, and materials suppliers to effectively engage with each other and rebuild the capacity of this supply chain by : � Identifying and removing impediments to the implementation of new construction and fabrication techniques and approaches for nuclear equipment, including system components and nuclear plants. � Providing and facilitating detailed scientific-based studies on new approaches and technologies that will have positive impacts on the cost of building of nuclear plants. � Analyzing and disseminating information about future nuclear fabrication technologies and how they could impact the North American and the International Nuclear Marketplace. � Facilitating dialog and initiate alignment among fabricators, owners, trade associations, and government agencies. � Supporting industry in helping to create a larger qualified nuclear supplier network. � Acting as an unbiased technology resource to evaluate, develop, and demonstrate new manufacturing technologies. � Creating welder and inspector training programs to help enable the necessary workforce for the upcoming construction work. � Serving as a focal point for technology, policy, and politically interested parties to share ideas and concepts associated with fabrication across the nuclear industry. The report the objectives and summaries of the Nuclear Fabrication Consortium projects. Full technical reports for each of the projects have been submitted as well.

Levesque, Stephen

2013-04-05T23:59:59.000Z

263

Nuclear Structure Aspects in Nuclear Astrophysics  

SciTech Connect

Nuclear Astrophysics as a broad and diverse field of study can be viewed as a magnifier of the impact of microscopic processes on the evolution of macroscopic events. One of the primary goals in Nuclear Astrophysics is the understanding of the nucleosynthesis processes that take place in the cosmos and the simulation of the correlated stellar and explosive burning scenarios. These simulations are strongly dependent on the input from Nuclear Physics which sets the time scale for all stellar dynamic processes--from giga-years of stellar evolution to milliseconds of stellar explosions--and provides the basis for most of the signatures that we have for the interpretation of these events--from stellar luminosities, elemental and isotopic abundances to neutrino flux from distant supernovae. The Nuclear Physics input comes through nuclear structure, low energy reaction rates, nuclear masses, and decay rates. There is a common perception that low energy reaction rates are the most important component of the required nuclear physics input; however, in this article we take a broader approach and present an overview of the close correlation between various nuclear structure aspects and their impact on nuclear astrophysics. We discuss the interplay between the weak and the strong forces on stellar time scales due to the limitations they provide for the evolution of slow and rapid burning processes. The effects of shell structure in nuclei on stellar burning processes as well as the impact of clustering in nuclei is outlined. Furthermore we illustrate the effects of the various nuclear structure aspects on the major nucleosynthesis processes that have been identified in the last few decades. We summarize and provide a coherent overview of the impact of all aspects of nuclear structure on nuclear astrophysics.

Smith, Michael Scott [ORNL

2006-12-01T23:59:59.000Z

264

Investigacin Supply chain collaboration  

E-Print Network (OSTI)

. These interactions among firms' decisions ask for alignment and coordination of actions. Therefore, game theory quantities, among others. Nowadays, business decisions are dominated by the globalization of markets, and that the decisions taken by a firm do also affect the performance of the other parties in the supply chain

Boucherie, Richard J.

265

NUFinancials Supply Chain  

E-Print Network (OSTI)

NUFinancials Supply Chain FMS801 & 803 Purchasing Glossary 03/31/2010 © 2010 Northwestern University FMS801 & 803 1 Purchasing Glossary Guide to terms used in iBuyNU and NUFinancials purchasing Term, faculty salary, office supplies. Similar to CUFS Object Code, Revenue Source, and Balance Sheet. Note

Shull, Kenneth R.

266

Negotiations Within Supply Chains  

Science Journals Connector (OSTI)

In this paper we consider a negotiation between a supplier and its retailer. Due to the supplier's commitments with other customers the negotiation is about the maximum order quantity the retailer can order at a fixed price. We propose a structuring ... Keywords: capacity, contract, cooperation, negotiations, scenario, supply chain management

Carsten Homburg; Christoph Schneeweiss

2000-05-01T23:59:59.000Z

267

Nuclear effects in Neutrino Nuclear Cross-sections  

E-Print Network (OSTI)

Nuclear effects in the quasielastic and inelastic scattering of neutrinos(antineutrinos) from nuclear targets have been studied. The calculations are done in the local density approximation which take into account the effect of nucleon motion as well as renormalisation of weak transition strengths in the nuclear medium. The inelastic reaction leading to production of pions is calculated in a $\\Delta$ dominance model taking into account the renormalization of $\\Delta$ properties in the nuclear medium.

S. K. Singh; M. Sajjad Athar

2007-10-24T23:59:59.000Z

268

Operational Experience in Nuclear Power Stations [and Discussion  

Science Journals Connector (OSTI)

...Operational Experience in Nuclear Power Stations...self-sustaining nuclear reaction to the present...time large-scale generation of electrical power from nuclear energy has become...the C.E.G.B. reactors have been in service...

1974-01-01T23:59:59.000Z

269

Nuclear Science Division Annual Report 1984-85  

E-Print Network (OSTI)

M. Xcssi. and W. Wolf. Nuclear-Reaction-Time Studies of U +K° Produced in Relativistic Nuclear Collisions Phys. Lett.Momentum Distributions of Nuclear Fragments in im Collisions

Mahoney Editor, Jeannette

2010-01-01T23:59:59.000Z

270

Nuclear Science Division: 1993 Annual report  

SciTech Connect

This report describes the activities of the Nuclear Science Division for the 1993 calendar year. This was another significant year in the history of the Division with many interesting and important accomplishments. Activities for the following programs are covered here: (1) nuclear structure and reactions program; (2) the Institute for Nuclear and Particle Astrophysics; (3) relativistic nuclear collisions program; (4) nuclear theory program; (5) nuclear data evaluation program, isotope project; and (6) 88-inch cyclotron operations.

Myers, W.D. [ed.

1994-06-01T23:59:59.000Z

271

Powering the Nuclear Navy | National Nuclear Security Administration  

NLE Websites -- All DOE Office Websites (Extended Search)

Powering the Nuclear Navy Powering the Nuclear Navy Home > About Us > Our Programs > Powering the Nuclear Navy Powering the Nuclear Navy The Naval Nuclear Propulsion Program provides militarily effective nuclear propulsion plants and ensures their safe, reliable and long-lived operation. This mission requires the combination of fully trained U.S. Navy men and women with ships that excel in endurance, stealth, speed, and independence from supply chains. NNSA's Navy Reactors Program provides the design, development and operational support required to provide militarily effective nuclear propulsion plants and ensure their safe, reliable and long-lived operation. This budget requests more than $1 billion to power a modern nuclear Navy: Continuation of design and development work for the OHIO-class

272

Current projects - Nuclear Data Program, Nuclear Engineering Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Current Projects Current Projects Nuclear Data Program Overview Current Projects & Recent Activities Collaborating Organizations Publications Nuclear Data Measurements (NDM) Reports Experimental Nuclear Data Resources Contact ND Program Related Resources Other Major Programs Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE Division on Flickr Nuclear Data Program Current Projects Bookmark and Share Compilation and evaluation of nuclear structure and decay data for the IAEA coordinated International Nuclear Structure and Decay Data Network. Argonne Nuclear Data Program has the responsibility for evaluations of A=176-179 & 199-209 mass chains. These evaluations are included in the world most completed and comprehensive nuclear structure

273

The Road to Controlled Nuclear Fusion  

Science Journals Connector (OSTI)

... is one atom of deuterium for every 7,000 atoms of ordinary hydrogen. Second, nuclear fusion does not generate as much radioactive waste as nuclear fission, so storage-a serious ... plants-does not constitute such a serious problem. By contrast with nuclear fission, however, nuclear fusion reactions cannot be sustained by themselves in matter which is in its normal state. ...

L. ARTSIMOVICH

1972-09-01T23:59:59.000Z

274

THE NUCLEAR SURFACE D. F. JACKSON  

E-Print Network (OSTI)

THE NUCLEAR SURFACE D. F. JACKSON Dept. of Physics, University of Surrey, Guildford, U.K. Abstract. -- Nuclear scattering and reactions which give information on the nuclear surface are described by a particular method. The results are compared with theories of the nuclear surface. 1. Introduction

Boyer, Edmond

275

Synthesis of Main-Chain Polyoxometalate-Containing Hybrid Polymers and Their Applications in Photovoltaic Cells  

Science Journals Connector (OSTI)

Hexamolybdate clusters have been embedded through covalent bonds into the main chain of poly(phenylene acetylene)s. These hybrid polymers were synthesized by palladium-catalyzed coupling reactions of a diiodo functionalized cluster with a diethynylbenzene ...

Meng Lu; Baohan Xie; Jeonghee Kang; Fang-Chung Chen; Yang Yang; Zhonghua Peng

2004-12-29T23:59:59.000Z

276

E-Print Network 3.0 - amplitudes spin chains Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

of 12 spins placed in a permanent magnetic field and interact- ing through a weak Ising... nuclear-spin quantum computer in a chain of impurity paramagnetic atoms in a...

277

The Tourism Global Value Chain  

E-Print Network (OSTI)

The Tourism Global Value Chain ECONOMIC UPGRADING AND WORKFORCE DEVELOPMENT Michelle Christian 2011 CENTER on GLOBALIZATION, GOVERNANCE & COMPETITIVENESS #12;The Tourism Global Value Chain: Economic: November 17, 2011 #12;The Tourism Global Value Chain: Economic Upgrading and Workforce Development i Table

Richardson, David

278

Nuclear Science References Database  

E-Print Network (OSTI)

The Nuclear Science References (NSR) database together with its associated Web interface, is the world's only comprehensive source of easily accessible low- and intermediate-energy nuclear physics bibliographic information for more than 210,000 articles since the beginning of nuclear science. The weekly-updated NSR database provides essential support for nuclear data evaluation, compilation and research activities. The principles of the database and Web application development and maintenance are described. Examples of nuclear structure, reaction and decay applications are specifically included. The complete NSR database is freely available at the websites of the National Nuclear Data Center http://www.nndc.bnl.gov/nsr and the International Atomic Energy Agency http://www-nds.iaea.org/nsr.

B. Pritychenko; E. B?ták; B. Singh; J. Totans

2014-07-08T23:59:59.000Z

279

Evidence for Nuclear Reactions in Imploding Bubbles  

Science Journals Connector (OSTI)

...Phys. Lett. 447 , 127 ( 1999 ). 4 See http://fusedweb.pppl.gov/. 5 See http://education.llnl.gov/lasers...Lett. B447, 127 (1999) [ADS]. See http://FusEdWeb.pppl.gov. See http://education.llnl.gov/lasers/fusion...

F. D. Becchetti

2002-03-08T23:59:59.000Z

280

Radioactive target needs for nuclear reactor physics and nuclear astrophysics , G. Barreau1  

E-Print Network (OSTI)

Radioactive target needs for nuclear reactor physics and nuclear astrophysics B.Jurado1* , G Gradignan, France 2 IPN, CNRS/IN2P3, Univ. Paris-Sud, 91405 Orsay, France Abstract: Nuclear reaction cross sections of short-lived nuclei are key inputs for new generation nuclear reactor simulations and for models

Boyer, Edmond

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Nuclear Energy  

NLE Websites -- All DOE Office Websites (Extended Search)

Research Programs >> Nuclear Energy Error Error Nuclear Energy Home - RCC cannot be displayed due to a timeout error. We recommend: * Refresh Nuclear Energy Home - RCC * Increasing...

282

chain 2chain 3 4row of 6 racks and 2 row of 5 racks  

E-Print Network (OSTI)

chain 1 chain 2chain 3 4row of 6 racks and 2 row of 5 racks chain 4 chain 10 6 5 4 3 2 1 chain 5 chain 6 f b fb f b b f f b b f 1 2 3 4 5 6 1 2 3 4 5 1:50 Rack A with 52 HU (2500*900*600) door door HV.0 1840.0 300.0 #12;chain 10 Layout of 2nd floorchain 4 chain 3 chain 2 chain 5 chain 6 chain 101:50 Rack

283

Wittig Reaction 33 Reaction: Synthesis of Alkenes  

E-Print Network (OSTI)

" an "ylide" Cl R3 R R3 OR2 Ph3P R1 H R2 R1 R Br R1 H R PPh3 SN2 Phosphonium Salt Aldehyde or Ketone AlkeneWittig Reaction 33 The Wittig Reaction: Synthesis of Alkenes Intro The "Wittig Reaction" is one elimination reactions (E1 or E2 reactions from alcohols or alkyl halides, for example), in elimination

Jasperse, Craig P.

284

Research in theoretical nuclear physics  

SciTech Connect

The work done during the past year or so may be divided into three separate areas, low energy nuclear reactions, intermediate energy physics and nuclear structure studies. In this paper, we shall separately summarize our achievements made in these three areas.

Udagawa, Takeshi.

1990-10-01T23:59:59.000Z

285

PHYSICAL REVIEW C 81, 064603 (2010) Pauli blocking and medium effects in nucleon knockout reactions  

E-Print Network (OSTI)

distributions up to 10% in the energy range Elab = 50­300 MeV/nucleon. The effect is more evident in reactions Nuclear structure calculations are now able to reproduce the measured masses, charge radii, and low-particle structure in short-lived nuclei typically uses direct nuclear reactions. Nucleon knockout reactions

Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

286

New nuclear physics for big bang nucleosynthesis  

SciTech Connect

We discuss nuclear reactions which could play a role in big bang nucleosynthesis. Most of these reactions involve lithium and beryllium isotopes and the rates for some of these have not previously been included in BBN calculations. Few of these reactions are well studied in the laboratory. We also discuss novel effects in these reactions, including thermal population of nuclear target states, resonant enhancement, and nonthermal neutron reaction products. We perform sensitivity studies which show that even given considerable nuclear physics uncertainties, most of these nuclear reactions have minimal leverage on the standard BBN abundance yields of {sup 6}Li and {sup 7}Li. Although a few have the potential to alter the yields significantly, we argue that this is unlikely.

Boyd, Richard N. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Brune, Carl R. [Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 (United States); Fuller, George M. [Department of Physics, University of California, San Diego, La Jolla, California 92093-0319 (United States); Smith, Christel J. [Physics Department, Arizona State University, Tempe, Arizona 85287-1404 (United States)

2010-11-15T23:59:59.000Z

287

New Nuclear Physics for Big Bang Nucleosynthesis  

E-Print Network (OSTI)

We discuss nuclear reactions which could play a role in Big Bang Nucleosynthesis (BBN). Most of these reactions involve lithium and beryllium isotopes and the rates for some of these have not previously been included in BBN calculations. Few of these reactions are well studied in the laboratory. We also discuss novel effects in these reactions, including thermal population of nuclear target states, resonant enhancement, and non-thermal neutron reaction products. We perform sensitivity studies which show that even given considerable nuclear physics uncertainties, most of these nuclear reactions have minimal leverage on the standard BBN abundance yields of 6Li and 7Li. Although a few have the potential to alter the yields significantly, we argue that this is unlikely.

Richard N. Boyd; Carl R. Brune; George M. Fuller; Christel J. Smith

2010-08-04T23:59:59.000Z

288

Absolute nuclear material assay using count distribution (LAMBDA) space  

DOE Patents (OSTI)

A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

Prasad, Manoj K. (Pleasanton, CA); Snyderman, Neal J. (Berkeley, CA); Rowland, Mark S. (Alamo, CA)

2012-06-05T23:59:59.000Z

289

Nuclear Debate  

Science Journals Connector (OSTI)

Nuclear Debate ... This month, the Senate will consider the nominations of two women to serve on the Nuclear Regulatory Commission. ... Svinicki is a nuclear engineer with experience in the Department of Energy’s nuclear energy programs. ...

JEFF JOHNSON

2012-06-11T23:59:59.000Z

290

Planetary and Protostellar Nuclear Fission: Implications for Planetary Change, Stellar Ignition and Dark Matter  

Science Journals Connector (OSTI)

...changes in the geomagnetic field. The concept that thermonuclear fusion reactions in stars are ignited by nuclear fission...protostellar nuclear fission reactors failed to ignite thermonuclear fusion reactions. The Royal Society is collaborating...

1994-01-01T23:59:59.000Z

291

Nuclear activation technique for analysis of laser induced energetic protons  

E-Print Network (OSTI)

. For that purpose, we have developed a method in which the particles induce nuclear reactions in a stack of copper for medical applications [6]). In addition, nuclear reaction yields and nuclear decay rates might be studied radioactive nuclei. In a stack of samples, each foil acts as a low energy proton filter for the following ones

Paris-Sud XI, Université de

292

[Experimental nuclear physics]. Final report  

SciTech Connect

This is the final report of the Nuclear Physics Laboratory of the University of Washington on work supported in part by US Department of Energy contract DE-AC06-81ER40048. It contains chapters on giant dipole resonances in excited nuclei, nucleus-nucleus reactions, astrophysics, polarization in nuclear reactions, fundamental symmetries and interactions, accelerator mass spectrometry (AMS), ultra-relativistic heavy ions, medium energy reactions, work by external users, instrumentation, accelerators and ion sources, and computer systems. An appendix lists Laboratory personnel, a Ph. D. degree granted in the 1990-1991 academic year, and publications. Refs., 41 figs., 7 tabs.

NONE

1991-04-01T23:59:59.000Z

293

Statistical Methods for Thermonuclear Reaction Rates and Nucleosynthesis Simulations  

E-Print Network (OSTI)

Rigorous statistical methods for estimating thermonuclear reaction rates and nucleosynthesis are becoming increasingly established in nuclear astrophysics. The main challenge being faced is that experimental reaction rates are highly complex quantities derived from a multitude of different measured nuclear parameters (e.g., astrophysical S-factors, resonance energies and strengths, particle and gamma-ray partial widths). We discuss the application of the Monte Carlo method to two distinct, but related, questions. First, given a set of measured nuclear parameters, how can one best estimate the resulting thermonuclear reaction rates and associated uncertainties? Second, given a set of appropriate reaction rates, how can one best estimate the abundances from nucleosynthesis (i.e., reaction network) calculations? The techniques described here provide probability density functions that can be used to derive statistically meaningful reaction rates and final abundances for any desired coverage probability. Examples ...

Iliadis, Christian; Coc, Alain; Timmes, F X; Champagne, Art E

2014-01-01T23:59:59.000Z

294

Theoretical Studies on the CH3CO + Cl Reaction: Hydrogen Abstraction versus CO Displacement  

E-Print Network (OSTI)

potential energy surface reveals this reaction to be a capture-limited association-elimination reaction the efficiency of a chain reaction. Recently Maricq et al.1 reported the real-time kinetic mea- surements for one earlier potential energy surface,3 is also consistent with an addition-elimination mechanism since

Nguyen, Minh Tho

295

Quantum reservoirs with ion chains  

E-Print Network (OSTI)

Ion chains are promising platforms for studying and simulating quantum reservoirs. One interesting feature is that their vibrational modes can mediate entanglement between two objects which are coupled through the vibrational modes of the chain. In this work we analyse entanglement between the transverse vibrations of two heavy impurity defects embedded in an ion chain, which is generated by the coupling with the chain vibrations. We verify general scaling properties of the defects dynamics and demonstrate that entanglement between the defects can be a stationary feature of these dynamics. We then analyse entanglement in chains composed of tens of ions and propose a measurement scheme which allows one to verify the existence of the predicted entangled state.

B. G. Taketani; T. Fogarty; E. Kajari; Th. Busch; Giovanna Morigi

2014-02-06T23:59:59.000Z

296

Theoretical nuclear physics: Final report for period February 1, 1984 to January 31, 1987  

SciTech Connect

Nuclear theory at the University of Colorado emphasizes the study of nuclear structure through the use of nuclear reactions. Recent efforts have been focussed on the role of relativistic models in nucleon-nucleus scattering and reactions. Further work delves into the underlying bases of the reaction theory itself.

Rost, E.; Kunz, P.D.

1987-01-23T23:59:59.000Z

297

Nuclear Physics B (Proc. Suppl.) 77 (1999) 64--72 Standard Solar Models  

E-Print Network (OSTI)

reactions. Thirty­nine experts in low energy nuclear ex­ periments and theory, representing many di#er­ ent In this section, I will first summarize the new and relevant results on nuclear fusion reactions and on the screening of nuclear reactions and then summarize the situation with respect to neu­ trino cross sections

Bahcall, John

298

Nuclear Data Sheets for A = 206  

Science Journals Connector (OSTI)

Evaluated nuclear structure and decay data for all nuclei within the A = 206 mass chain are presented. The experimental data are evaluated and recommended best values for level and gamma-ray energies, quantum numbers, lifetimes, gamma-ray intensities and other nuclear properties are presented. Inconsistencies and discrepancies that exist in the literature are noted. This work supersedes the earlier evaluation by E. Browne (1999Br39), published in Nuclear Data Sheets 88, 29 (1999).

F.G. Kondev

2008-01-01T23:59:59.000Z

299

Nuclear Resonance Fluorescence for Nuclear Materials Assay  

E-Print Network (OSTI)

Potential of Nuclear Resonance Fluorescence . . . . . . . .2.9.1 Nuclear ThomsonSections . . . . . . . . . . . . . . . Nuclear Resonance

Quiter, Brian Joseph

2010-01-01T23:59:59.000Z

300

Error analysis for resonant thermonuclear reaction rates  

Science Journals Connector (OSTI)

A detailed presentation is given of estimating uncertainties in thermonuclear reaction rates for stellar nucleosynthesis involving narrow resonances, starting from random errors in measured or calculated resonance and nuclear level properties. Special attention is given to statistical matters such as probability distributions, error propagation, and correlations between errors. Interpretation of resulting uncertainties in reaction rates and the distinction between symmetric and asymmetric errors are also discussed. Computing reaction rate uncertainties is described. We give examples from explosive nucleosynthesis by hydrogen burning on light nuclei.

William J. Thompson; C. Iliadis

1999-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Low-energy proton capture reactions  

SciTech Connect

An overview of experimental problems in measuring the cross sections for (p,?) and (p,n) reactions at low energies is given with a specific emphasis on electron screening in metallic targets. Thick target ?-ray and neutron yields are compared for Ni and NiO targets, V and VO{sub 2} targets and Mn and MnO targets. The {sup 1}H({sup 7}Li,?){sup 4}He reaction was studied in inverse kinematics with hydrogen loaded into Pd and PdAg alloy foils from gas phase. Based on these results, a new approach to electron screening in nuclear reactions is suggested.

Lipoglavsek, M.; Cvetinovic, A.; Gajevic, J.; Likar, A.; Vavpetic, P. [Jozef Stefan Institute, Jamova ulica 39, Ljubljana (Slovenia); Petrovic, T. [Jozef Stefan Institute, Jamova ulica 39, Ljubljana, Slovenia and Cosylab d.d., Teslova ulica 30, Ljubljana (Slovenia)

2014-05-09T23:59:59.000Z

302

Internet-Enabled Supply ChainsInternet-Enabled Supply Chains Quan Z. Sheng, University of Adelaide  

E-Print Network (OSTI)

89 Internet-Enabled Supply ChainsInternet-Enabled Supply Chains Quan Z. Sheng, University of the Internet-enabled Supply Chain 89 Key Supply Chain Processes and the Internet 89 Impacts of Internet-Enabled Supply Chains 92 Enabling Technologies for Internet-Enabled Supply Chain Management 92 Internet-based EDI

Sheng, Michael

303

Nuclear Returns  

Science Journals Connector (OSTI)

Nuclear Returns ... For the first time since 1978, the Nuclear Regulatory Commission has given the green light for a new U.S. nuclear power plant. ... NRC granted a license to Southern Co. to build and operate twin 1,100-MW reactors adjacent to two operating nuclear power plants at its Vogtle nuclear facility, near Waynesboro, Ga. ...

JEFF JOHNSON

2012-02-19T23:59:59.000Z

304

A,B,C`s of nuclear science  

SciTech Connect

This introductory level presentation contains information on nuclear structure, radioactivity, alpha decay, beta decay, gamma decay, half-life, nuclear reactions, fusion, fission, cosmic rays, and radiation protection. Nine experiments with procedures and test questions are included.

Noto, V.A. [Mandeville High School, LA (United States); Norman, E.B.; Chan, Yuen-Dat; Dairiki, J.; Matis, H.S.; McMahan, M.A.; Otto, R. [Lawrence Berkeley Lab., CA (United States)

1995-08-07T23:59:59.000Z

305

Analysis of cross sections using various nuclear potential  

SciTech Connect

The relevant astrophysical reaction rates which are derived from the reaction cross sections are necessary input to the reaction network. In this work, we analyse several theoretical models of the nuclear potential which give better prediction of the cross sections for some selected reactions.

Aziz, Azni Abdul [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Kulliyah of Science, International Islamic University Malaysia, 25200 Kuantan (Malaysia); Quantum Science Center, Faculty of Science, University of Malaya, 50603 Kuala Lump (Malaysia); Kassim, Hasan Abu [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Quantum Science Center, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia); Institute of Space Science, Universiti Kebangsaan Malaysia, 43600 Bangi, Se (Malaysia); Yusof, Norhasliza [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Quantum Science Center, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia); Muhammad Zamrun, F. [Quantum Science Center, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia); Jurusan Fisika FMIPA, Universitas Haluoleo Kendari, Sulawesi Tenggara, J3232 (Indonesia)

2014-05-02T23:59:59.000Z

306

Extracorporeal membrane oxygenation promotes long chain fatty...  

NLE Websites -- All DOE Office Websites (Extended Search)

membrane oxygenation promotes long chain fatty acid oxidation in the immature swine heart in vivo. Extracorporeal membrane oxygenation promotes long chain fatty acid oxidation...

307

Total supply chain cost model  

E-Print Network (OSTI)

Sourcing and outsourcing decisions have taken on increased importance within Teradyne to improve efficiency and competitiveness. This project delivered a conceptual framework and a software tool to analyze supply chain ...

Wu, Claudia

2005-01-01T23:59:59.000Z

308

Exploring medium effects on the nuclear force  

SciTech Connect

This STI product contains a description of results from theoretical studies in nuclear physics. The goal is a systematic investigation of the nuclear force in the nuclear medium. The problems addressed are: density-dependent effective interactions as seen through proton-nucleus reactions, nuclear matter with unequal densities of protons and neutrons, applications to asymmetric nuclei through predictions of neutron radii and neutron skins.

F. Sammarruca

2004-04-18T23:59:59.000Z

309

Folden Group - Heavy Element Nuclear and Radiochemistry at Texas...  

NLE Websites -- All DOE Office Websites (Extended Search)

elements. This involves measuring the production cross sections for a variety of nuclear fusion reactions, and using theoretical models to interpret the results. Our work is...

310

Nuclear Fusion  

Science Journals Connector (OSTI)

Although not yet developed at the commercial stage, nuclear fusion technology is still being considered as a ... used in nuclear warfare. Since research in nuclear fusion for the production of energy started abou...

Ricardo Guerrero-Lemus; José Manuel Martínez-Duart

2013-01-01T23:59:59.000Z

311

Nuclear Nonproliferation  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Nonproliferation As more countries embrace nuclear power as a cost-effective and clean alternative to fossil fuels, the need exists to ensure that the nuclear fuel cycle is...

312

Nuclear Engineering Nuclear Criticality Safety  

E-Print Network (OSTI)

Nuclear Engineering Nuclear Criticality Safety The Nuclear Engineering Division (NE) of Argonne National Laboratory is experienced in performing criticality safety and shielding evaluations for nuclear, and neutron spectra. The NE nuclear criticality safety (NCS) capabilities are based on a staff with decades

Kemner, Ken

313

Nuclear Energy  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Energy Idaho National Laboratory is the Department of Energy's lead nuclear energy research and development facility. Building upon its legacy responsibilities,...

314

Nuclear Hydrogen  

NLE Websites -- All DOE Office Websites (Extended Search)

Error Error Nuclear Hydrogen - RCC cannot be displayed due to a timeout error. We recommend: * Refresh Nuclear Hydrogen - RCC * Increasing your portlet timeout setting. *...

315

Nuclear Physics  

NLE Websites -- All DOE Office Websites (Extended Search)

Underground Research Facility in South Dakota, which will search for neutrinoless double-beta decay. Strong Los Alamos programs in nuclear data and nuclear theory supports...

316

Nuclear Masses in Astrophysics  

E-Print Network (OSTI)

Among all nuclear ground-state properties, atomic masses are highly specific for each particular combination of N and Z and the data obtained apply to a variety of physics topics. One of the most crucial questions to be addressed in mass spectrometry of unstable radionuclides is the one of understanding the processes of element formation in the Universe. To this end, accurate atomic mass values of a large number of exotic nuclei participating in nucleosynthesis are among the key input data in large-scale reaction network calculations. In this paper, a review on the latest achievements in mass spectrometry for nuclear astrophysics is given.

Christine Weber; Klaus Blaum; Hendrik Schatz

2008-12-09T23:59:59.000Z

317

Nuclear Matter and Nuclear Dynamics  

E-Print Network (OSTI)

Highlights on the recent research activity, carried out by the Italian Community involved in the "Nuclear Matter and Nuclear Dynamics" field, will be presented.

M Colonna

2009-02-26T23:59:59.000Z

318

THE STRUCTURE AND REACTIONS OF NEUTRON-RICH NUCLEI  

E-Print Network (OSTI)

dissociation experiments 351 2.3. Low-energy behaviour of "Li dissociation cross 6.2. Direct measurements 355 of the understanding of the structure and reactions of neutron-rich nuclei. The properties of the low-lying soft giant and total nuclear reaction cross section isalso calculated using the microscopic tp, p 2-Glauber theory

Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

319

Sustainable Supply Chain | Data.gov  

NLE Websites -- All DOE Office Websites (Extended Search)

Sustainable Supply Chain Sustainable Supply Chain Sustainable Supply Chains Submissions Let's Talk About Sustainable Supply Chain Welcome to the Sustainable Supply Chain Community of Practice Bringing together government, industry, associations, non-profits and academic institutions to achieve more sustainable supply chains. Sustainable Supply Chain - New Updates New Updates View More Be a Champion Be a champion The Sustainable Supply Chain Community of Practice seeks champions from industry, academia and non-profits to lead each of the community market sectors. Do you know or are you a member of a leading edge organization that is implementing sustainable supply chain practices within one of the seven current community market sectors? If yes, nominate the organization as a Champion. Sustainable supply chain practices lead to cost savings,

320

Cold nuclear fusion  

SciTech Connect

Recent accelerator experiments on fusion of various elements have clearly demonstrated that the effective cross-sections of these reactions depend on what material the target particle is placed in. In these experiments, there was a significant increase in the probability of interaction when target nuclei are imbedded in a conducting crystal or are a part of it. These experiments open a new perspective on the problem of so-called cold nuclear fusion.

Tsyganov, E. N., E-mail: edward.tsyganov@utsouthwestern.edu [University of Texas Southwestern Medical Center at Dallas (United States)

2012-02-15T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Nuclear isotope thermometry  

Science Journals Connector (OSTI)

We discuss different aspects which might influence temperatures deduced from experimental isotopic yields in the multifragmentation process. It is shown that fluctuations due to the finite size of the system and distortions due to the decay of hot primary fragments conspire to blur the temperature determination in multifragmentation reactions. These facts suggest that caloric curves obtained through isotope thermometers, which were taken as evidence for a first-order phase transition in nuclear matter, should be investigated very carefully.

S. R. Souza, W. P. Tan, R. Donangelo, C. K. Gelbke, W. G. Lynch, and M. B. Tsang

2000-11-10T23:59:59.000Z

322

Nuclear choices  

SciTech Connect

This book contains part of the series New Liberal Arts, which is intended to make science and technology more accessible to students of the liberal arts. Volume in hand provides a comprehensive, multifaceted examination of nuclear energy, in nontechnical terms. Wolfson explains the basics of nuclear energy and radiation, nuclear power..., and nuclear weapons..., and he invites readers to make their own judgments on controversial nuclear issues. Illustrated with photos and diagrams. Each chapter contains suggestions for additional reading and a glossary. For policy, science, and general collections in all libraries. (ES) Topics contained include Atoms and nuclei. Effects and uses of radiation. Energy and People. Reactor safety. Nuclear strategy. Defense in the nuclear age. Nuclear power, nuclear weapons, and nuclear futures.

Wolfson, R.

1991-01-01T23:59:59.000Z

323

Science Based Stockpile Stewardship, Uncertainty Quantification, and Surrogate Reactions  

SciTech Connect

Stewardship of this nation's nuclear weapons is predicated on developing a fundamental scientific understanding of the physics and chemistry required to describe weapon performance without the need to resort to underground nuclear testing and to predict expected future performance as a result of intended or unintended modifications. In order to construct more reliable models, underground nuclear test data is being reanalyzed in novel ways. To improve the interpretation of these experiments with quantified uncertainties, improved nuclear data is required. As an example, the thermonuclear yield of a device was often inferred through the use of radiochemical detectors. Conversion of the detector activations observed to thermonuclear yield was accomplished through explosion code calculations (models) and a good set of nuclear reaction cross-sections. Because of the unique high-fluence environment of an exploding nuclear weapon, many reactions occurred on radioactive nuclides, for which only theoretically calculated cross-sections are available. Surrogate nuclear reactions at STARS/LIBERACE offer the opportunity to measure cross-sections on unstable nuclei and thus improve the quality of the nuclear reaction cross-section sets. One radiochemical detector that was loaded in devices was mono-isotopic yttrium ({sup 89}Y). Nuclear reactions produced {sup 87}Y and {sup 88}Y which could be quantified post-shot as a ratio of {sup 87}Y/{sup 88}Y. The yttrium cross-section set from 1988 is shown in Figure 1(a) and contains approximately 62 cross-sections interconnecting the yttrium nuclides. The 6 experimentally measured cross-sections are shown in Figure 1(b). Any measurement of cross-sections on {sup 87}Y or {sup 88}Y would improve the quality of the cross-section set. A recent re-evaluation of the yttrium cross-section set was performed with many more calculated reaction cross-sections included.

Stoyer, M A; McNabb, D P; Burke, J T; Bernstein, L A

2009-08-06T23:59:59.000Z

324

Nuclear Astrophysics in Rare Isotope Facilities  

E-Print Network (OSTI)

Nuclear reactions in stars are difficult to measure directly in the laboratory at the small astrophysical energies. In recent years indirect methods with rare isotopes have been developed and applied to extract low-energy astrophysical cross sections.

C. A. Bertulani

2009-11-02T23:59:59.000Z

325

Nuclear data sheets for A = 210  

Science Journals Connector (OSTI)

Nuclear structure information pertaining to A=210 has been reviewed. The level properties obtained from decay and reaction experiments are shown in the drawings. Experimental methods, references, and comment are given in the text.

B. Harmatz

1981-01-01T23:59:59.000Z

326

Differential evolution Markov chain with snooker updater and fewer chains  

SciTech Connect

Differential Evolution Markov Chain (DE-MC) is an adaptive MCMC algorithm, in which multiple chains are run in parallel. Standard DE-MC requires at least N=2d chains to be run in parallel, where d is the dimensionality of the posterior. This paper extends DE-MC with a snooker updater and shows by simulation and real examples that DE-MC can work for d up to 50--100 with fewer parallel chains (e.g. N=3) by exploiting information from their past by generating jumps from differences of pairs of past states. This approach extends the practical applicability of DE-MC and is shown to be about 5--26 times more efficient than the optimal Normal random walk Metropolis sampler for the 97.5% point of a variable from a 25--50 dimensional Student T{sub 3} distribution. In a nonlinear mixed effects model example the approach outperformed a block-updater geared to the specific features of the model.

Vrugt, Jasper A [Los Alamos National Laboratory; Ter Braak, Cajo J F [NON LANL

2008-01-01T23:59:59.000Z

327

Shutdown system for a nuclear reactor  

DOE Patents (OSTI)

An ultimate shutdown system is provided for termination of neutronic activity in a nuclear reactor. The shutdown system includes bead chains comprising spherical containers suspended on a flexible cable. The containers are comprised of mating hemispherical shells which provide a ruggedized enclosure for reactor poison material. The bead chains, normally suspended above the reactor core on storage spools, are released for downward travel upon command from an external reactor monitor. The chains are capable of horizontal movement, so as to flow around obstructions in the reactor during their downward motion.

Groh, Edward F. (Naperville, IL); Olson, Arne P. (Western Springs, IL); Wade, David C. (Naperville, IL); Robinson, Bryan W. (Oak Lawn, IL)

1984-01-01T23:59:59.000Z

328

Record of Cycling Operation of the Natural Nuclear Reactor in the Oklo/Okelobondo Area in Gabon  

E-Print Network (OSTI)

of variability of the long-term fundamental physical constants [5,6] to storage of nuclear wastes in geological on how to retain nuclear wastes, including fission Xe and Kr, and prevent uncontrolled runaway chain

329

Chapter 17 - Nuclear Fusion  

Science Journals Connector (OSTI)

Publisher Summary Nuclear fusion, the joining of light nuclei of hydrogen into heavier nuclei of helium, has potential environmental, safety and proliferation characteristics as an energy source, as well as adequate fuel to power civilization for times long compared to human history. It is, however, more challenging to convert to an energy source than nuclear fission. This chapter introduces the physics, advantages, difficulties, progress, economics and prospects for fusion energy power plants. Nuclear fusion is the process, in which light nuclei can release large amounts of energy if they combine, or fuse, into heavier nuclei. The principal nuclear reactions which have been considered for reactor concepts involve reactions of isotopes of the two lightest elements: hydrogen and helium. The fuel costs for fusion reactors will be negligible in comparison with the value of the electricity produced. It is difficult to precisely assess the cost of fusion-generated electricity until there is experience with an operating power plant, since the cost will be dependent upon the reliability and the frequency and expense of maintenance, both of which are likely to improve with the hindsight of experience. A fusion reactor does not directly emit CO2 or other greenhouse gases, or any combustion products that contribute to acid rain, and the indirect emissions due to factors like fuel gathering and transport, plant construction and maintenance, and activated parts storage would be small. Thus, fusion power would not have appreciable adverse effects upon global warming, atmospheric quality or acidification of the oceans, lakes and streams.

Larry R. Grisham

2008-01-01T23:59:59.000Z

330

Modelling proton-induced reactions at low energies in the MARS15 code  

E-Print Network (OSTI)

An implementation of both the ALICE code and TENDL evaluated nuclear data library in order to describe nuclear reactions by low-energy projectiles in the Monte Carlo code MARS15 is presented. Comparisons between results of modelling and experimental data on reaction cross sections and secondary particle distributions are shown as well.

Rakhno, Igor L; Gudima, Konstantin K

2015-01-01T23:59:59.000Z

331

defense nuclear security | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

nuclear security | National Nuclear Security Administration People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response...

332

Chernobyl Nuclear Accident | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

Chernobyl Nuclear Accident | National Nuclear Security Administration People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response...

333

Countering Nuclear Terrorism and Trafficking | National Nuclear...  

National Nuclear Security Administration (NNSA)

Countering Nuclear Terrorism and Trafficking | National Nuclear Security Administration People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy...

334

Methyl p-Hydroxyphenyllactate and Nuclear Type II Binding Sites in Malignant Cells: Metabolic Fate and Mammary Tumor Growth  

Science Journals Connector (OSTI)

...Heterogeneity of estrogen-binding sites and the nuclear matrix. In: G. Maul (ed.). The Nuclear Matrix and the Nuclear Envelope, pp. 259-269. New York...inhibition on mitochondria! ATPase and energy-linked reactions in submitochondrial...

Barry M. Markaverich; Rebecca R. Gregory; MaryAnn Alejandro; Francis S. Kittrell; Daniel Medina; James H. Clark; Manju Varma; and Rajender S. Varma

1990-03-01T23:59:59.000Z

335

computational infrastructure for nuclear astrophysics Michael Smith, Physics Division, Oak Ridge Na:onal Lab coordinator@nucastrodata.org  

E-Print Network (OSTI)

computational infrastructure for nuclear astrophysics Michael Smith, Physics Division, Oak Ridge Na:onal Lab coordinator@nucastrodata.org #12;computational infrastructure for nuclear astrophysics system overview ·work with nuclear information, reaction rates, & simulations ·operates "in

336

Data resources for nuclear medicine  

SciTech Connect

The objective of this article is to list data resources needed for nuclear medicine and provide information on how to access them. This list will include publications of data compilations or evaluations, databases, and data processing codes for both nuclear structure and decay, as well as reaction data. Sources of bibliographic and related information on nuclear data are also be listed. The authors of this article have used their judgement in choosing a representative list of data sources; a more complete listing may be found in the references.

Bhat, M.R. [Brookhaven National Lab., Upton, NY (United States); Lemmel, H.D. [International Atomic Energy Agency, Vienna (Austria). Nuclear Data Section

1995-07-01T23:59:59.000Z

337

Research in heavy-ion nuclear physics  

SciTech Connect

This report discusses the following topics: Fusion-fission in light nuclear systems; High-resolution Q-value measurement for the {sup 24}Mg+{sup 24}Mg reaction; Heavy-ion reactions and limits to fusion; and Hybrid MWPC-Bragg curve detector development.

Sanders, S.J.; Prosser, F.W.

1992-01-01T23:59:59.000Z

338

Subbarrier fusion reactions and many-particle quantum tunneling  

E-Print Network (OSTI)

Low energy heavy-ion fusion reactions are governed by quantum tunneling through the Coulomb barrier formed by a strong cancellation of the repulsive Coulomb force with the attractive nuclear interaction between the colliding nuclei. Extensive experimental as well as theoretical studies have revealed that fusion reactions are strongly influenced by couplings of the relative motion of the colliding nuclei to several nuclear intrinsic motions. Heavy-ion subbarrier fusion reactions thus provide a good opportunity to address a general problem on quantum tunneling in the presence of couplings, which has been a popular subject in the past decades in many branches of physics and chemistry. Here we review theoretical aspects of heavy-ion subbarrier fusion reactions from the view point of quantum tunneling in systems with many degrees of freedom. Particular emphases are put on the coupled-channels approach to fusion reactions, and the barrier distribution representation for multi-channel penetrability. We also discuss ...

Hagino, K

2012-01-01T23:59:59.000Z

339

Separable Optical Potentials for (d,p) Reactions  

E-Print Network (OSTI)

An important ingredient for applications of nuclear physics to e.g. astrophysics or nuclear energy are the cross sections for reactions of neutrons with rare isotopes. Since direct measurements are often not possible, indirect methods like (d,p) reactions must be used instead. Those (d,p) reactions may be viewed as effective three-body reactions and described with Faddeev techniques. An additional challenge posed by (d,p) reactions involving heavier nuclei is the treatment of the Coulomb force. To avoid numerical complications in dealing with the screening of the Coulomb force, recently a new approach using the Coulomb distorted basis in momentum space was suggested. In order to implement this suggestion, one needs not only to derive a separable representation of neutron- and proton-nucleus optical potentials, but also compute the Coulomb distorted form factors in this basis.

Ch. Elster; L. Hlophe; V. Eremenko; F. M. Nunes; G. Arbanas; J. E. Escher; I. J. Thompson

2014-10-05T23:59:59.000Z

340

Separable Optical Potentials for (d,p) Reactions  

E-Print Network (OSTI)

An important ingredient for applications of nuclear physics to e.g. astrophysics or nuclear energy are the cross sections for reactions of neutrons with rare isotopes. Since direct measurements are often not possible, indirect methods like (d,p) reactions must be used instead. Those (d,p) reactions may be viewed as effective three-body reactions and described with Faddeev techniques. An additional challenge posed by (d,p) reactions involving heavier nuclei is the treatment of the Coulomb force. To avoid numerical complications in dealing with the screening of the Coulomb force, recently a new approach using the Coulomb distorted basis in momentum space was suggested. In order to implement this suggestion, one needs not only to derive a separable representation of neutron- and proton-nucleus optical potentials, but also compute the Coulomb distorted form factors in this basis.

Elster, Ch; Eremenko, V; Nunes, F M; Arbanas, G; Escher, J E; Thompson, I J

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Nuclear Science  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Science Science and Engineering Education Sourcebook 2013 American Nuclear Society US Department of Energy Nuclear Science & Engineering Education Sourcebook 2013 North American Edition American Nuclear Society Education, Training, and Workforce Division US Department of Energy Office of Nuclear Energy Editor and Founder John Gilligan Professor of Nuclear Engineering North Carolina State University Version 5.13 Welcome to the 2013 Edition of the Nuclear Science and Engineering Education (NS&EE) Sourcebook. We have evolved and improved! The core mission of the Sourcebook has not changed, however. Our purpose is to facilitate interaction among faculty, students, industry, and government agencies to accomplish nuclear research, teaching and service activities. Since 1986 we have compiled critical information on nuclear

342

nuclear security  

National Nuclear Security Administration (NNSA)

3%2A en Shaping the future of nuclear detection http:nnsa.energy.govblogshaping-future-nuclear-detection

343

Nudat: Nuclear Structure and Decay Data from the National Nuclear Data Center (NNDC)  

DOE Data Explorer (OSTI)

NuDat allows users to search and plot nuclear structure and decay data interactively. NuDat was developed by the National Nuclear Data Center (NNDC)but utilizes contributions from physicists around the world. It provides an interface between web users and several databases containing nuclear structure, nuclear decay and some neutron-induced nuclear reaction information. Users can search for nuclear level properties (energy, half-life, spinparity), gamma-ray information (energy, intensity, multipolarity, coincidences), radiation information following nuclear decay (energy, intensity, dose), and neutron-induced reaction data from the BNL-325 book (thermal cross section and resonance integral). The information provided by NuDat 2 can be viewed in tables, level schemes and an interactive chart of nuclides.

344

Nuclear spectroscopic studies  

SciTech Connect

The Nuclear Physics group at the University of Tennessee, Knoxville is involved in several aspects of heavy-ion physics including both nuclear structure and reaction mechanisms. While our main emphasis is on experimental problems involving heavy-ion accelerators, we have maintained a strong collaboration with several theorists in order to best pursue the physics of our measurements. During the last year we have led several experiments at the Holifield Heavy Ion Research Facility and participated in others at Argonne National Laboratory. Also, we continue to be very active in the collaboration to study ultra-relativistic heavy ion physics utilizing the SPS accelerator at CERN in Geneva, Switzerland and in a RHIC detector R D project. Our experimental work is in four broad areas: (1) the structure of nuclei at high angular momentum, (2) heavy-ion induced transfer reactions, (3) the structure of nuclei far from stability, and (4) ultra-relativistic heavy-ion physics. The results of studies in these particular areas will be described in this document in sections IIA, IIB, IIC, and IID, respectively. Areas (1), (3), and (4) concentrate on the structure of nuclear matter in extreme conditions of rotational motion, imbalance of neutrons and protons, or very high temperature and density. Area (2) pursues the transfer of nucleons to states with high angular momentum, both to learn about their structure and to understand the transfer of particles, energy, and angular momentum in collisions between heavy ions. An important component of our program is the strong emphasis on the theoretical aspects of nuclear structure and reactions.

Bingham, C.R.; Guidry, M.W.; Riedinger, L.L.; Sorensen, S.P.

1993-02-08T23:59:59.000Z

345

Cationic triple-chain amphiphiles facilitate vesicle fusion compared to double-chain or single-chain analogues  

E-Print Network (OSTI)

-chain analogues. Two types of vesicle fusion experiments were conducted, mixing of oppositely charged vesicles-determining step for certain cell types is endosomal escape, which can occur either by a fusion or disruptionCationic triple-chain amphiphiles facilitate vesicle fusion compared to double-chain or single

Smith, Bradley D.

346

TRIMOLECULAR REACTIONS OF URANIUM HEXAFLUORIDE WITH WATER  

SciTech Connect

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 mechanism is warranted to resolve the remaining discrepancies between the predicted mechanisms and experimental observations.

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

2010-02-25T23:59:59.000Z

347

Nuclear Ukraine  

Science Journals Connector (OSTI)

... SIR - Your article (Nature 365, 599; 1993) on the US-Ukraine stalemate over nuclear weapons prompts the following remarks. The United States made a mistake ... nuclear weapons prompts the following remarks. The United States made a mistake in not recognizing Ukraine as a legitimate successor state to the Soviet nuclear arsenal and is still insisting that ...

Arno Arrak

1994-01-13T23:59:59.000Z

348

Supply Chain Management Faculty Brian Fugate  

E-Print Network (OSTI)

relationships, strategy and sustainability in the supply chain, and she won the College of Business Excellence involvement in new product development, and sustainability practices in supply chain management. He has

349

An integrative framework for architecting supply chains  

E-Print Network (OSTI)

This thesis explores the limitations of classic models of supply chain management, and proposes a new view based on the concept of value-driven supply chains, and a method of analysis and design based on the concepts of ...

Cela Díaz, Fernando

2006-01-01T23:59:59.000Z

350

Charged-Particle Thermonuclear Reaction Rates: IV. Comparison to Previous Work  

E-Print Network (OSTI)

We compare our Monte Carlo reaction rates (see Paper II of this series) 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 series), and (ii) newly available nuclear physics information (see Paper III of this series).

Christian Iliadis; Richard Longland; Art Champagne; Alain Coc

2010-04-23T23:59:59.000Z

351

5. Experimental Nuclear Research: Interview with Junkichi Itoh and Osamu Minakawa  

Science Journals Connector (OSTI)

......able to produce any nuclear reactions in that way...the first artificial nuclear reactions done in 1apan...this Cockroft-Walton accelerator was used mainly to provide...impossible to continue the nuclear physics experiments...four counters and a few vacuum tubes were all that......

Junkichi Itoh; Osamu Minakawa; L. M. Brown; M. Konuma

1991-03-01T23:59:59.000Z

352

Modeling nuclear fusion in dense plasmas using a cryogenic non-neutral plasmaa...  

E-Print Network (OSTI)

the nuclear reaction rate in a dense neutral plasma and the energy equipartition rate in a strongly magnetized and at low temperatures, cyclotron energy, like nuclear energy, is released only through rare close as for nuclear reactions. Rate enhancements of up to 1010 are measured in simulations of equipartition

California at San Diego, University of

353

An Improved Reaction Rate Formulation for Charged-Particle Induced Thermonuclear Reaction of {sup 2}H(d,{gamma}){sup 4}He  

SciTech Connect

The reaction rate formula utilized in compilations such as the Nuclear Astrophysics Compilation of Reaction Rates (NACRE) uses low energy approximation due to temperatures in stars are in the region of a few keVs. Most nuclear reaction experiments were done in MeV range and the interior temperatures of massive stars are {approx}10{sup 9} K. Hence an improved formulation for calculating the nuclear reaction rate that is applicable to high temperatures is discussed in this work. The exact tunneling probability that is applicable for all energies is obtained by solving the Schroedinger equation. This yields an enhanced expression for the astrophysical S-factor for calculating the thermonuclear reaction rate at high temperature. The thermonuclear reaction rate from this work is applied to the {sup 2}H(d,{gamma}){sup 4}He reaction and is compared with the NACRE compilation. This improved reaction rate can be included in the nuclear reaction network in a Big Bang nucleosynthesis (BBN) code or a stellar nuclear network code.

Aziz, Azni Abdul; Yusof, Norhasliza; Idris, Mahirah; Kassim, Hasan Abu [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia)

2011-03-30T23:59:59.000Z

354

Nuclear Engineer (Nuclear Safety Specialist)  

Energy.gov (U.S. Department of Energy (DOE))

A successful candidate of this position will serve as a Nuclear Engineer (Nuclear Safety Specialist) responsible for day-to-day technical monitoring, and evaluation of aspects of authorization...

355

4 studies of the 1.84.8 GeV 3 Au reactions.  

E-Print Network (OSTI)

to very low energies, indicative of emission from an extended nuclear system with / 0 1/3. Predictions into the nuclear equation of state EOS at low densities, limiting temperatures in the nuclear medium, and liquid a higher level of understanding; e.g., reaction time scales, the excitation energy and degree

Maryland at College Park, University of

356

The Offshore Services Global Value Chain  

E-Print Network (OSTI)

The Offshore Services Global Value Chain ECONOMIC UPGRADING AND WORKFORCE DEVELOPMENT Karina & COMPETITIVENESS #12;The Offshore Services Global Value Chain: Economic Upgrading and Workforce Development "Skills & Competitiveness, Duke University Posted: November 17, 2011 #12;The Offshore Services Global Value Chain: Economic

Richardson, David

357

The NACRE Thermonuclear Reaction Compilation and Big Bang Nucleosynthesis  

E-Print Network (OSTI)

The theoretical predictions of big bang nucleosynthesis (BBN) are dominated by uncertainties in the input nuclear reaction cross sections. In this paper, we examine the impact on BBN of the recent compilation of nuclear data and thermonuclear reactions rates by the NACRE collaboration. We confirm that the adopted rates do not make large overall changes in central values of predictions, but do affect the magnitude of the uncertainties in these predictions. Therefore, we then examine in detail the uncertainties in the individual reaction rates considered by NACRE. When the error estimates by NACRE are treated as 1\\sigma limits, the resulting BBN error budget is similar to those of previous tabulations. We propose two new procedures for deriving reaction rate uncertainties from the nuclear data: one which sets lower limits to the error, and one which we believe is a reasonable description of the present error budget. We propagate these uncertainty estimates through the BBN code, and find that when the nuclear data errors are described most accurately, the resulting light element uncertainties are notably smaller than in some previous tabulations, but larger than others. Using these results, we derive limits on the cosmic baryon-to-photon ratio $\\eta$, and compare this to independent limits on $\\eta$ from recent balloon-borne measurements of the cosmic microwave background radiation (CMB). We discuss means to improve the BBN results via key nuclear reaction measurements and light element observations.

Richard H. Cyburt; Brian D. Fields; Keith A. Olive

2001-05-17T23:59:59.000Z

358

Intermediate-energy nuclear chemistry workshop  

SciTech Connect

This report contains the proceedings of the LAMPF Intermediate-Energy Nuclear Chemistry Workshop held in Los Alamos, New Mexico, June 23-27, 1980. The first two days of the Workshop were devoted to invited review talks highlighting current experimental and theoretical research activities in intermediate-energy nuclear chemistry and physics. Working panels representing major topic areas carried out indepth appraisals of present research and formulated recommendations for future research directions. The major topic areas were Pion-Nucleus Reactions, Nucleon-Nucleus Reactions and Nuclei Far from Stability, Mesonic Atoms, Exotic Interactions, New Theoretical Approaches, and New Experimental Techniques and New Nuclear Chemistry Facilities.

Butler, G.W.; Giesler, G.C.; Liu, L.C.; Dropesky, B.J.; Knight, J.D.; Lucero, F.; Orth, C.J.

1981-05-01T23:59:59.000Z

359

Nuclear Astrophysics in Rare Isotope Facilities C.A. Bertulania  

E-Print Network (OSTI)

, beam energies should be in the range of a few 10-100 MeV per nucleon [5]. Low energy reactions projectile velocity va, the low energy reaction A + x = B + c is induced at very low (even vanishing and Astronomy, Texas A&M University, Commerce, TX 75429, USA Nuclear reactions in stars are difficult to measure

Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

360

Nuclear Deterrence  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Deterrence Nuclear Deterrence Nuclear Deterrence LANL's mission is to develop and apply science and technology to ensure the safety, security, and effectiveness of the U.S. nuclear deterrent; reduce global threats; and solve other emerging national security and energy challenges. April 12, 2012 A B-2 Spirit bomber refuels from a KC-135 Stratotanker A B-2 Spirit bomber refuels from a KC-135 Stratotanker. Contact Operator Los Alamos National Laboratory (505) 667-5061 Charlie McMillan, Director: "For the last 70 years there has not been a world war, and I have to think that our strong deterrent has something to do with that fact." Mission nuclear weapons Charlie McMillan, Director of Los Alamos National Laboratory 1:06 Director McMillan on nuclear deterrence While the role and prominence of nuclear weapons in U.S. security policy

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Nuclear excitation energy in muon capture: A reply  

Science Journals Connector (OSTI)

The parametrization of total muon capture rates in terms of a mean nuclear excitation energy E¯?, recently proposed by Christillin, Dellafiore, and Rosa-Clot, is reexamined in view of recent criticisms. The previously obtained results are reconfirmed.NUCLEAR REACTIONS ?-+A(N, Z)??+A(N+1, Z-1); muon capture; closure approximation; mean nuclear excitation energies.

P. Christillin, A. Dellafiore, and M. Rosa-Clot

1975-08-01T23:59:59.000Z

362

Nuclear Science and Technology, November 2000. NEUTRON CROSS SECTION EVALUATIONS  

E-Print Network (OSTI)

Nuclear Science and Technology, November 2000. 1 NEUTRON CROSS SECTION EVALUATIONS FOR 238 U UP and Power Engineering, 249020 Obninsk, Russia A.Ventura ENEA, Nuclear Data Center and INFN, Bologna Section of the statistical description that includes direct, pre-equilibrium and equilibrium mechanisms of nuclear reactions

363

NUCLEAR SCIENCE PUBLICATIONS OF ROBERT B. WEISENMILLER, PH.D.  

E-Print Network (OSTI)

1 NUCLEAR SCIENCE PUBLICATIONS OF ROBERT B. WEISENMILLER, PH.D. 1. Two-proton Pickup Studies, K. H. Wilcox, G. J. Wozniak, M. S. Zisman, and J. Cerny. Nuclear Physics A 280, 217. 1977. 3 Spectroscopic Measurement via Exotic Nuclear Rearrangement: The Reaction 26 Mg (7 Li, 8 B), 25 Ne. With K. H

364

Method for polymer synthesis in a reaction well  

DOE Patents (OSTI)

A method of synthesis is described for building a polymer chain, oligonucleotides in particular, by sequentially adding monomer units to at least one solid support for growing and immobilizing a polymer chain thereon in a liquid reagent solution. The method includes the step of: (A) depositing a liquid reagent in a reaction well in contact with at least one solid support and at least one monomer unit of the polymer chain affixed to the solid support. The well includes at least one orifice extending into the well, and is of a size and dimension to form a capillary liquid seal to retain the reagent solution in the well to enable polymer chain growth on the solid support. The method further includes the step of (B) expelling the reagent solution from the well, while retaining the polymer chain therein. This is accomplished by applying a first gas pressure to the reaction well such that a pressure differential between the first gas pressure and a second gas pressure exerted on an exit of the orifice exceeds a predetermined amount sufficient to overcome the capillary liquid seal and expel the reagent solution from the well through the orifice exit. 9 figs.

Brennan, T.M.

1998-09-29T23:59:59.000Z

365

Single chain elasticity and thermoelasticity of polyethylene  

E-Print Network (OSTI)

Single-chain elasticity of polyethylene at $\\theta$ point up to 90% of stretching with respect to its contour length is computed by Monte-Carlo simulation of an atomistic model in continuous space. The elasticity law together with the free-energy and the internal energy variations with stretching are found to be very well represented by the wormlike chain model up to 65% of the chain elongation, provided the persistence length is treated as a temperature dependent parameter. Beyond this value of elongation simple ideal chain models are not able to describe the Monte Carlo data in a thermodynamic consistent way. This study reinforces the use of the wormlike chain model to interpret experimental data on the elasticity of synthetic polymers in the finite extensibility regime, provided the chain is not yet in its fully stretched regime. Specific solvent effects on the elasticity law and the partition between energetic and entropic contributions to single chain elasticity are investigated.

John T. Titantah; Carlo Pierleoni; Jean-Paul Ryckaert

2002-09-05T23:59:59.000Z

366

From nucleons to nuclei to fusion reactions S. Quaglioni1, P. Navratil2,1, R. Roth3, and W. Horiuchi4  

E-Print Network (OSTI)

reactions. Providing the research community with accurate nuclear fusion data is one of the longstanding and ionized state of matter at which they take place, nuclear fusion reactions can be very challenging or even as fusion- experiment simulations rely on various nuclear input data such as cross sections (or

Roth, Robert

367

Parameter Estimates for High-Level Nuclear Transport in Fractured Porous Media  

E-Print Network (OSTI)

accurate description of the transport and dispersion of nuclear contam- ination through a granitic medium with a standard model for the transport and dispersion of a nuclear chain in an unfractured, singleParameter Estimates for High-Level Nuclear Transport in Fractured Porous Media Jim Douglas, Jr. #3

Douglas Jr., Jim

368

Kaon production in heavy ion reactions at intermediate energies  

E-Print Network (OSTI)

The article reviews the physics related to kaon and antikaon production in heavy ion reactions at intermediate energies. Chiral dynamics predicts substantial modifications of the kaon properties in a dense nuclear environment. The status of the theoretical predictions as well as experimental evidences for medium effects such as repulsive/attractive mass shifts for $K^+/K^-$ are reviewed. In the vicinity of the thresholds, and even more pronounced below threshold, the production of strangeness is a highly collective process. Starting from elementary reaction channels the phenomenology of $K^+$ and $K^-$ production, i.e. freeze-out densities, time scales etc. as derived from experiment and theoretical transport calculations is presented. Below threshold kaon production shows a high sensitivity on the nuclear compression reached in heavy ion reactions. This allows to put constraints on the nuclear equation-of-state which are finally discussed.

Christian Fuchs

2005-09-01T23:59:59.000Z

369

A Safer Nuclear Enterprise  

Science Journals Connector (OSTI)

...2012 at the Nuclear Security...leadership in nuclear enterprise...multinational assessment of emerging risks and consequences...to assess nuclear risks in...or nuclear terrorism. States...and nuclear power. Since 1945...nuclear power plant can mean...

Sidney D. Drell; George P. Shultz; Steven P. Andreasen

2012-06-08T23:59:59.000Z

370

Nuclear astrophysics  

SciTech Connect

The problem of core-collapse supernovae is used to illustrate the many connections between nuclear astrophysics and the problems nuclear physicists study in terrestrial laboratories. Efforts to better understand the collapse and mantle ejection are also motivated by a variety of interdisciplinary issues in nuclear, particle, and astrophysics, including galactic chemical evolution, neutrino masses and mixing, and stellar cooling by the emission of new particles. The current status of theory and observations is summarized.

Haxton, W.C.

1992-12-31T23:59:59.000Z

371

Nuclear astrophysics  

SciTech Connect

The problem of core-collapse supernovae is used to illustrate the many connections between nuclear astrophysics and the problems nuclear physicists study in terrestrial laboratories. Efforts to better understand the collapse and mantle ejection are also motivated by a variety of interdisciplinary issues in nuclear, particle, and astrophysics, including galactic chemical evolution, neutrino masses and mixing, and stellar cooling by the emission of new particles. The current status of theory and observations is summarized.

Haxton, W.C.

1992-01-01T23:59:59.000Z

372

Nuclear Counterterrorism  

Directives, Delegations, and Requirements

The Order defines requirements for the protection of sensitive improvised nuclear device information and provides a framework to support DOE activities related to nuclear counterterrorism. (A supplemental DOE Manual, Control of and Access to Improvised Nuclear Device Information, provides requirements and procedures for protecting Sigma 20 information.) Appendices A and B are Official Use Only. Point of contact is Adam Boyd (NA-82), 202-586-0010. Cancels DOE O 457.1 and DOE M 457.1-1.

2013-08-26T23:59:59.000Z

373

Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration  

E-Print Network (OSTI)

, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL ­ Supply chains and logistics ­ Systems of systems (e.g., the nuclear fuel cycle, fleet management) #12

Langerhans, Brian

374

E-Print Network 3.0 - aromatic side chain Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

1. Interactions between oppositely charged amino acid side- chains in the interaction interface... chain- main chain, main chain- sidechain and sidechain-side- chain. Only...

375

Nuclear and gravitational energies in stars  

E-Print Network (OSTI)

The force that governs the evolution of stars is gravity. Indeed this force drives star formation, imposes thermal and density gradients into stars at hydrostatic equilibrium and finally plays the key role in the last phases of their evolution. Nuclear power in stars governs their lifetimes and of course the stellar nucleosynthesis. The nuclear reactions are at the heart of the changes of composition of the baryonic matter in the Universe. This change of composition, in its turn, has profound consequences on the evolution of stars and galaxies. The energy extracted from the gravitational, respectively nuclear reservoirs during the lifetimes of stars of different masses are estimated. It is shown that low and intermediate mass stars (M 8 Msol), which explode in a supernova explosion, extract more than 5 times more energy from the gravitational reservoir than from the nuclear one. We conclude by discussing a few important nuclear reactions and their link to topical astrophysical questions.

Meynet, Georges; Ekström, Sylvia

2013-01-01T23:59:59.000Z

376

Nuclear Power  

Science Journals Connector (OSTI)

Nuclear Power ... THIS WEEK’S issue contains six letters on nuclear power, a representative sample of the letters C&EN received in response to the editorial, “Resist Hysteria,” I wrote shortly after the earthquake and tsunami in Japan devastated the Fukushima Daiichi Nuclear Power Station (C&EN, March 21, page 5). ... Four of the six letters take sharp issue with the primary point I made in the editorial, which was that, despite the severity of the situation in Japan, nuclear power remains an essential component of our overall energy mix for the near to mid-term because it will help us avert the worst impacts of global climate disruption. ...

RUDY M. BAUM

2011-05-09T23:59:59.000Z

377

NUCLEAR STUDIES  

Science Journals Connector (OSTI)

Japanese nuclear power plant crisis sparks examination of U.S. REACTORS ... Calls are particularly zeroing in on reactors similar in location and design to those in Japan. ...

JEFF JOHNSON

2011-04-04T23:59:59.000Z

378

Nuclear Properties of 93237  

Science Journals Connector (OSTI)

The isotope Np237, produced as the decay product of the previously known 6.8-day U237, has been isolated with carrier material and some of its nuclear properties measured. The U237 was formed by means of the reaction U238(n,2n)U237. Np237 decays with the emission of alphaparticles with a half-life of about 3×106 years. It has been shown that the upper limit for the cross section for the fission of Np237 with slow neutrons is less than 1 percent of that of U235.

Arthur C. Wahl and Glenn T. Seaborg

1948-05-01T23:59:59.000Z

379

Chart of Nuclides from the National Nuclear Data Center (NNDC)  

DOE Data Explorer (OSTI)

The Chart of Nuclides is a software product that allows users to search and plot nuclear structure and nuclear decay data interactively. The Chart of Nuclides was developed by the National Nuclear Data Center (NNDC). It provides an interface between web users and several databases containing nuclear structure, nuclear decay and some neutron-induced nuclear reaction information. Using the Chart of Nuclides, it is possible to search for nuclear level properties (energy, half-life, spin-parity), gamma-ray information (energy, intensity, multipolarity, coincidences),radiation information following nuclear decay (energy, intensity, dose), and neutron-induced reaction data from the BNL-325 book (thermal cross section and resonance integral). The information provided by the Chart of Nuclides can be seen in tables, level schemes and an interactive chart of nuclides. (From the Chart of Nuclides Description at http://www.nndc.bnl.gov/chart/help/index.jsp?product=chart)

380

Detailed Chemical Kinetic Reaction Mechanism for Biodiesel Components Methyl Stearate and Methyl Oleate  

SciTech Connect

New chemical kinetic reaction mechanisms are developed for two of the five major components of biodiesel fuel, methyl stearate and methyl oleate. The mechanisms are produced using existing reaction classes and rules for reaction rates, with additional reaction classes to describe other reactions unique to methyl ester species. Mechanism capabilities were examined by computing fuel/air autoignition delay times and comparing the results with more conventional hydrocarbon fuels for which experimental results are available. Additional comparisons were carried out with measured results taken from jet-stirred reactor experiments for rapeseed methyl ester fuels. In both sets of computational tests, methyl oleate was found to be slightly less reactive than methyl stearate, and an explanation of this observation is made showing that the double bond in methyl oleate inhibits certain low temperature chain branching reaction pathways important in methyl stearate. The resulting detailed chemical kinetic reaction mechanism includes more approximately 3500 chemical species and more than 17,000 chemical reactions.

Naik, C; Westbrook, C K; Herbinet, O; Pitz, W J; Mehl, M

2010-01-22T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Nuclear radiation electronic gear  

Science Journals Connector (OSTI)

Nuclear radiation electronic gear ... Examines the line of nuclear radiation instrumentation offered by Nuclear-Chicago Corporation and Victoreen Instrument Company. ... Nuclear / Radiochemistry ...

S. Z. Lewin

1961-01-01T23:59:59.000Z

382

Nuclear Weapons Journal  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Weapons Journal Nuclear Weapons Journal x The Nuclear Weapons Journal ceased publication after Issue 2, 2009. Below are Nuclear Weapons Journal archived issues. Issue 2,...

383

Nuclear Forces and Nuclear Systems  

NLE Websites -- All DOE Office Websites (Extended Search)

Forces and Nuclear Systems Forces and Nuclear Systems Our goal is to achieve a description of nuclear systems ranging in size from the deuteron to nuclear matter and neutron stars using a single parameterization of the nuclear forces. Our work includes both the construction of two- and three-nucleon potentials and the development of many-body techniques for computing nuclear properties with these interactions. Detailed quantitative, computationally intense studies are essential parts of this work. In the last decade we have constructed several realistic two- and three-nucleon potential models. The NN potential, Argonne v18, has a dominant charge-independent piece plus additional charge-dependent and charge-symmetry-breaking terms, including a complete electromagnetic interaction. It fits 4301 pp and np elastic scattering data with a chi**2

384

Nuclear astrophysics studies with ultra-peripheral heavy-ion collisions  

E-Print Network (OSTI)

I describe in very simple terms the theoretical tools needed to investigate ultra-peripheral nuclear reactions for nuclear astrophysics purposes. For a more detailed account, see arXiv:0908.4307.

C. A. Bertulani

2009-12-17T23:59:59.000Z

385

Notice of Intent to Revise DOE O 452.4B, Security and Control of Nuclear Explosives and Nuclear Weapons, dated 1-11-2010  

Directives, Delegations, and Requirements

Recent events have revealed that there are organizations that are seeking to insert malicious software and/or components into the nuclear weapon supply chain that can alter the functionality of the weapon and possible cause DAU.

2014-09-18T23:59:59.000Z

386

Nuclear Systems Modeling, Simulation & Validation | Nuclear Science...  

NLE Websites -- All DOE Office Websites (Extended Search)

Research Areas Fuel Cycle Science & Technology Fusion Nuclear Science Isotope Development and Production Nuclear Security Science & Technology Nuclear Systems Modeling, Simulation...

387

Nuclear Materials Management & Safeguards System | National Nuclear...  

National Nuclear Security Administration (NNSA)

System Nuclear Materials Management & Safeguards System NMMSS U.S. Department of Energy U.S. Nuclear Regulatory Commission Nuclear Materials Management & Safeguards...

388

Reaction Rate Sensitivity of the gamma-Process Path  

E-Print Network (OSTI)

The location of the (gamma,p)/(gamma,n) and (gamma,alpha)/(gamma,n) line at gamma-process temperatures is discussed, using recently published reaction rates based on global Hauser-Feshbach calculations. The results can directly be compared to previously published, classic gamma-process discussions. The nuclei exhibiting the largest sensitivity to uncertainties in nuclear structure and reaction parameters are specified.

T. Rauscher

2004-07-16T23:59:59.000Z

389

The reaction of cesium hydroxide with 4-phenylvaleric acid  

E-Print Network (OSTI)

Alkali Metal Hycroxide Solutions Used in Potentio- metric and Spectrophotometric Titrations with 4-Phenylvaleric Acid 17 Samples for Nuclear Magnetic Resonance Spectra 18 Concentration of 4-Phenylvaleric Acid in Carbon Tetrachloride for Infrared.... Similarly, nuclear magnetic resonance techniques may be used to determine whether any TT-bonding involving the phenyl ring of 4- phenylvaleric acid occurs during its reaction with cesium hydroxide. If any such bonding to the n-electrons of the ring occurs...

Caughfield, Arvie Jeane

2012-06-07T23:59:59.000Z

390

Nuclear options  

Science Journals Connector (OSTI)

... sad if transient commercial expediency led the country to take risks now by adopting nuclear reactor designs from abroad which are in some respects technically less sound than those produced at ... much lower priority. It can be anticipated, however; that although the types of nuclear reactor selected as the best that Britain could build next may be suitable for unit designs ...

G. R. Bainbridge

1974-06-21T23:59:59.000Z

391

In-medium effects for nuclear matter in the Fermi energy domain D. Durand,1  

E-Print Network (OSTI)

In-medium effects for nuclear matter in the Fermi energy domain O. Lopez,1 D. Durand,1 G. Lehaut,1 of nuclear reactions in the Fermi energy domain. I. INTRODUCTION Transport properties in nuclear matter energy domain, transport features should exhibit the in- terplay between mean-field (nuclear degrees

Boyer, Edmond

392

Ph.D. Theses 1. M. Dasgupta Study of cross section and average angular momenta in fusion reactions of 28  

E-Print Network (OSTI)

-fission reactions (BARC, 1994) 7. S. Chattopadhyay Investigation of nuclear structure at high spins in mass-80) 12. A.K. Pandey Studies on the fission properties of low Z elements by solid state nuclear track in 32 to 55 MeV excitation energy region on 28 Si (BARC, 1995) 14. B.J. Roy Reaction Mechanism in heavy

Shyamasundar, R.K.

393

Statistical Methods for Thermonuclear Reaction Rates and Nucleosynthesis Simulations  

E-Print Network (OSTI)

Rigorous statistical methods for estimating thermonuclear reaction rates and nucleosynthesis are becoming increasingly established in nuclear astrophysics. The main challenge being faced is that experimental reaction rates are highly complex quantities derived from a multitude of different measured nuclear parameters (e.g., astrophysical S-factors, resonance energies and strengths, particle and gamma-ray partial widths). We discuss the application of the Monte Carlo method to two distinct, but related, questions. First, given a set of measured nuclear parameters, how can one best estimate the resulting thermonuclear reaction rates and associated uncertainties? Second, given a set of appropriate reaction rates, how can one best estimate the abundances from nucleosynthesis (i.e., reaction network) calculations? The techniques described here provide probability density functions that can be used to derive statistically meaningful reaction rates and final abundances for any desired coverage probability. Examples are given for applications to s-process neutron sources, core-collapse supernovae, classical novae, and big bang nucleosynthesis.

Christian Iliadis; Richard Longland; Alain Coc; F. X. Timmes; Art E. Champagne

2014-09-19T23:59:59.000Z

394

Nuclear correlation and finite interaction-range effects in high-energy $(e,e'p)$ nuclear transparency  

E-Print Network (OSTI)

Nuclear transparency is calculated for high-energy, semi-inclusive $(e,e'p)$ reactions, by accounting for all orders of Glauber multiple-scattering and by using realistic finite-range $p N$ interaction and (dynamically and statistically) correlated nuclear wave functions. The nuclear correlation effect is reduced due to the $p N$ finite-range effect. The net effect is small, and depends sensitively on details of the nuclear correlations in finite nuclei, which are poorly known at present.

Ryoichi Seki; T. D. Shoppa; Akihisa Kohama; Koichi Yazaki

1995-12-06T23:59:59.000Z

395

Spontaneous symmetry breaking and the chain criterion  

Science Journals Connector (OSTI)

For the first time I have rigorously proved the equivalence between the necessary symmetry condition of the original Landau theory of second-order phase transitions, the chain criterion, and some recent propositions. I have introduced the new chain criterion which contains a powerful corollary. I have also established the validity of the chain criterion beyond the Landau theory, emphasizing its use as an algorithm for calculation of little groups.

Marko V. Jari?

1981-04-01T23:59:59.000Z

396

Cross section limits for the {sup 248}Cm({sup 25}Mg,4n-5n){sup 268,269}Hs reactions  

SciTech Connect

We report on an attempt to produce and detect {sup 268}Hs and {sup 269}Hs in the nuclear fusion reaction {sup 25}Mg+{sup 248}Cm using the gas phase chemistry apparatus COMPACT. No decay chains attributable to the decay of hassium isotopes were observed during the course of this experiment. From the nonobservation of {sup 269}Hs we derive a cross section limit of 0.4 pb (63% confidence limit) for the reaction {sup 248}Cm({sup 25}Mg,4n){sup 269}Hs at a center-of-target beam energy of 140 MeV. The evaluated cross section limit for the {sup 248}Cm({sup 25}Mg,5n){sup 268}Hs reaction depends on the assumed half-life of unknown {sup 268}Hs. Current systematics of the half-lives for even-even Hs isotopes suggests a value of 0.5 s, resulting in a cross section limit of 1.3 pb.

Dvorak, J.; Dvorakova, Z.; Schuber, R.; Tuerler, A.; Yakushev, A. [Technische Universitaet Muenchen, D-85748 Garching (Germany); Bruechle, W.; Duellmann, Ch. E.; Jaeger, E.; Schaedel, M.; Schausten, B.; Schimpf, E. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany); Eberhardt, K.; Thoerle, P. [Universitaet Mainz, D-55128 Mainz (Germany); Eichler, R. [Paul Scherrer Institut, CH-5232 Villigen (Switzerland); Nagame, Y. [Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Qin, Z. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Semchenkov, A. [Technische Universitaet Muenchen, D-85748 Garching (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany); Wegrzecki, M. [Institute of Electron Technology, PL-02-668 Warsaw (Poland)

2009-03-15T23:59:59.000Z

397

Nuclear Reactor Materials and Fuels  

Science Journals Connector (OSTI)

Nuclear reactor materials and fuels can be classified into six categories: Nuclear fuel materials Nuclear clad materials Nuclear coolant materials Nuclear poison materials Nuclear moderator materials

Dr. James S. Tulenko

2012-01-01T23:59:59.000Z

398

Reactor for exothermic reactions  

DOE Patents (OSTI)

A liquid phase process is described for oligomerization of C[sub 4] and C[sub 5] isoolefins or the etherification thereof with C[sub 1] to C[sub 6] alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120 to 300 F. Wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

Smith, L.A. Jr.; Hearn, D.; Jones, E.M. Jr.

1993-03-02T23:59:59.000Z

399

Aqueous Phase Reactions  

Science Journals Connector (OSTI)

The use of water as a solvent for carrying out organic reactions was nonexistent till about the middle of the 20th century. In view of the environmental concerns caused by pollution of organic solvents, chemis...

V. K. Ahluwalia; M. Kidwai

2004-01-01T23:59:59.000Z

400

Photosynthesis: First reactions  

Science Journals Connector (OSTI)

Photosynthesis: First reactions ... Studies of photosynthesis using isotopic tracers have revealed the first steps of carbohydrate synthesis, from which are derived the multitude of compounds needed by the plant. ... Photosynthesis ...

Andrew A. Benson

1954-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Linear chain tensioning of moored production vessels  

SciTech Connect

Part 1 of this two-part series discussed the worldwide floating production vessel (FPV) market and evolution of the linear puller concept. The three principal types of chain jack systems - hollow ram, single and twin cylinders - were introduced. And advantages of this relatively new form of passive mooring were outlined. This concluding article covers applications of linear chain pullers on various vessels, including use on an example 35,000-t North Sea semi-submersible. Chain wear and how linear pullers avoid wear associated with windlass-type systems are discussed, along with the optimization possible through use of a swiveling chain fair-lead latch (SCFL).

Peters, B. (Bardex Corp., London (United Kingdom))

1993-06-01T23:59:59.000Z

402

Better Plants Supply Chain Pilot Overview  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

be helping their suppliers achieve energy and cost savings, while simultaneously reducing carbon emissions. This can lead to stronger, more competitive supply chains and help...

403

Optimizing a Retailer's Containerized Import Supply Chain  

E-Print Network (OSTI)

M.G. , 2005. Distribution network design: New problems andapproach for distribution chain design in agile virtualinto a strategic distribution network design model with

Davidson, Evan Taitz

2012-01-01T23:59:59.000Z

404

(Nuclear theory). [Research in nuclear physics  

SciTech Connect

This report discusses research in nuclear physics. Topics covered in this paper are: symmetry principles; nuclear astrophysics; nuclear structure; quark-gluon plasma; quantum chromodynamics; symmetry breaking; nuclear deformation; and cold fusion. (LSP)

Haxton, W.

1990-01-01T23:59:59.000Z

405

Supply Chain The effective supply chain has become a new organizational and operational  

E-Print Network (OSTI)

MBA in Supply Chain Management #12;The effective supply chain has become a new organizational a virtual integration of business partners to achieve new levels of efficiency and productivity, as well

Lin, Xiaodong

406

nuclear security | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

security | National Nuclear Security Administration People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our...

407

Nuclear Incident Team | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

Incident Team | National Nuclear Security Administration People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing...

408

nuclear navy | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

navy | National Nuclear Security Administration People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our...

409

nuclear threat science | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

threat science | National Nuclear Security Administration People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing...

410

Nuclear Operations | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

Nuclear Security Administration People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure...

411

Nuclear Radius and Nuclear Forces  

Science Journals Connector (OSTI)

The difference between the radius of the nuclear matter distribution and the nuclear force radius, RN?1.4A13×10-13 cm, for heavy nuclei (A>100) is interpreted as a consequence of the finite range of nuclear forces. Assuming that the nuclear matter distribution coincides with the charge distribution as determined at Stanford (RC=1.12A13×10-13 cm is the distance at which the charge density falls to one half value) we sum up the nuclear interactions of an incident nucleon for various proposed internucleon potentials, V(r). We also evaluate contributions from the spin, charge, and matter polarizations induced in the nuclear distributions by the incident nucleon as a test of the convergence of these calculations. The aim here is to infer some features of nuclear forces which satisfy saturation requirements and at the same time give rise to an appreciable nuclear attraction for an incident nucleon at RN. Analyses of the scattering of neutrons and protons by heavy nuclei suggest a nuclear attraction ?14 Mev at a distance RN.These considerations are primarily sensitive to the long range behavior of the direct, central part of V(r). The key point which emerges from them is that the nuclear forces must contain long range (~ meson Compton wavelength) direct, central attractions which will be felt by an incident nucleon at RN before the shorter range repulsions (hard cores, many-body forces, or exchange interactions), which are responsible for saturation, become effective. Such interactions can be constructed phenomenologically, but are not found in recent meson-theoretically deduced potentials.

S. D. Drell

1955-10-01T23:59:59.000Z

412

Comparison of reactions for the production of 258,257Db: 208Pb(51V,xn) and 209Bi(50Ti,xn)  

E-Print Network (OSTI)

as 10 - 15 MeV, hence ‘cold’ fusion. These low excitationmodel for predicting cold fusion reaction cross sections [7,been produced in ‘cold’ nuclear fusion reactions with Pb and

Gates, Jacklyn M.

2008-01-01T23:59:59.000Z

413

State-to-state dynamics of the ClCH3OH\\HClCH2OH reaction Hans A. Bechtel, Jon P. Camden, and Richard N. Zarea)  

E-Print Network (OSTI)

be accelerated by exciting one type of nuclear motion rather than another? If the reagent has multiple reaction-expanded into a vacuum chamber using a custom designed ``late-mixing'' nozzle. The title reaction is initiated

Zare, Richard N.

414

Nuclear War  

SciTech Connect

Several chapters in Last Aid warrant the attention of the medical profession. What is known and not known about acute biologic effects following a nuclear explosion is described. The social, physical, and environmental impact of nuclear war on urban population centers is described. How nuclear weapons could affect the composition of the ozone layer and the effects this could have on human survival, including possible interruption of the aquatic ecosystem to produce single-cell organisms for the food cycle, especially seafood is noted.

MacLeod, G.K.

1983-01-01T23:59:59.000Z

415

Climate Change, Nuclear Power and Nuclear  

E-Print Network (OSTI)

Climate Change, Nuclear Power and Nuclear Proliferation: Magnitude Matters Rob Goldston MIT IAP biomass wind hydro coal CCS coal nat gas CCS nat gas nuclear Gen IV nuclear Gen III nuclear Gen II 5-1 Electricity Generation: CCS and Nuclear Power Technology Options Available Global Electricity Generation WRE

416

Nuclear Data Resources for Capture gamma-Ray Spectroscopy and Related Topics  

SciTech Connect

Nuclear reaction data play an important role in nuclear reactor, medical, and fundamental science and national security applications. The wealth of information is stored in internally adopted ENDF-6 and EXFOR formats. We present a complete calculation of resonance integrals, Westcott factors, thermal and Maxwellian-averaged cross sections for Z = 1-100 using evaluated nuclear reaction data. The addition of newly-evaluated neutron reaction libraries, and improvements in data processing techniques allows us to calculate nuclear industry and astrophysics parameters, and provide additional insights on all currently available neutron-induced reaction data. Nuclear reaction calculations will be discussed and an overview of the latest reaction data developments will be given.

Pritychenko, B.; Pritychenko,B.

2011-08-18T23:59:59.000Z

417

PHYS 390 Lecture 18 -Reactions I -Tunneling 18 -1 2001 by David Boal, Simon Fraser University. All rights reserved; further resale or copying is strictly prohibited.  

E-Print Network (OSTI)

. 4.1 and 4.5 Coulomb barrier to nuclear reactions The elementary particle reactions that occurred K. Such low temperatures affect reactions in two ways: · the reactions may occur through the phenomenon of quantum mechanical tunneling · the low energy end of a thermal distribution of particles may

Boal, David

418

Introduction The Sustainable Supply Chain Taxes Permits Integration Future Research Sustainable Supply Chains  

E-Print Network (OSTI)

Introduction The Sustainable Supply Chain Taxes Permits Integration Future Research Sustainable;Introduction The Sustainable Supply Chain Taxes Permits Integration Future Research 1 Introduction 2 The Sustainable Supply Chain 3 Taxes 4 Permits 5 Integration 6 Future Research Dissertation Defense by Trisha D

Nagurney, Anna

419

Some thoughts on opportunities with reactions using radioactive beams  

SciTech Connect

I was asked to talk about the use of radioactive beams for nuclear reactions. My overall perspective is that the scientific justification for such studies must be done carefully. To go to the added complexity of radioactive beams one must clearly demonstrate the need for obtaining information about nuclear structure or processes, information that is not otherwise available. On the other hand, much of what we know about nuclear structure comes from nuclear reactions with stable nuclear beams and targets. While a certain amount of information about far from stability nuclei may be obtained from the study of their radioactive decays, this is limited. Our knowledge and understanding of nuclear structure comes from stable nuclei: energy levels, their spins and parties, and very importantly the matrix elements characterizing them. These are largely determined by reaction studies with normal stable nuclei. The extension of such studies to unstable nuclei, far from stability, may well hold qualitative surprises, or at the very least give a firmer basis to our understanding of nuclear structure. Perhaps it is a matter of taste, but if one wishes to start on this endeavor then it is best to begin with simple, easily accessible features. The simplest'' nuclei are the ones that form doubly-closed shells and the easiest features to explore initially are the single-particle states and the collective excitations that one can build on these. I would like to emphasize that a unique facility for this type of study is about to come into operation in Darmstadt where the ESR storage ring will capture radioactive beams from fragmentation products and cool them to useful energies for reaction studies.

Schiffer, J.P. (Argonne National Lab., IL (USA) Chicago Univ., IL (USA))

1990-01-01T23:59:59.000Z

420

Nuclear Medicine  

Science Journals Connector (OSTI)

Nuclear medicine is the branch of medicine that is concerned with the use of in the diagnosis, management, and treatment of disease. It usually uses small amounts of radioactive materials or , substances th...

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Nuclear Waste  

Science Journals Connector (OSTI)

Nuclear waste is radioactive material no longer considered valuable...238U, 235U, and 226Ra (where the latter decays to 222Rn gas by emitting an alpha particle) or formed through fission of fissile radioisotopes ...

Rob P. Rechard

2014-01-01T23:59:59.000Z

422

Nuclear Golf  

E-Print Network (OSTI)

Broadcast Transcript: Pay no attention to that nuclear warhead behind the 18th hole; just shout "Fore!" and drive your Titleist down the fairway. In a development that is bizarre even by North Korean standards, the country ...

Hacker, Randi; Tsutsui, William

2006-12-06T23:59:59.000Z

423

Nuclear Fuels  

Science Journals Connector (OSTI)

The core of a nuclear reactor is composed of a controlled critical configuration of a fissile material, which in strict a sense is the fuel. This fissile material is contained in a matrix, normally a ceramic c...

Rudy J. M. Konings; Thierry Wiss…

2011-01-01T23:59:59.000Z

424

Nuclear Energy!  

NLE Websites -- All DOE Office Websites (Extended Search)

driver, see the Nuclear Clean Air Energy race car and receive a special clean energy patch on October 21 from 6:30 - 7:30 p.m. Space is limited RSVP by October 4 Hands-on...

425

Nuclear forces  

SciTech Connect

These lectures present an introduction into the theory of nuclear forces. We focus mainly on the modern approach, in which the forces between nucleons emerge from low-energy QCD via chiral effective field theory.

Machleidt, R. [Department of Physics, University of Idaho, Moscow, Idaho 83844 (United States)

2013-06-10T23:59:59.000Z

426

Advanced Nuclear Reactors | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Advanced Nuclear Advanced Nuclear Reactors Advanced Nuclear Reactors Turbulent Flow of Coolant in an Advanced Nuclear Reactor Visualizing Coolant Flow in Sodium Reactor Subassemblies Sodium-cooled Fast Reactor (SFR) Coolant Flow At the heart of a nuclear power plant is the reactor. The fuel assembly is placed inside a reactor vessel where all the nuclear reactions occur to produce the heat and steam used for power generation. Nonetheless, an entire power plant consists of many other support components and key structures like coolant pipes; pumps and tanks including their surrounding steel framing; and concrete containment and support structures. The Reactors Product Line within NEAMS is concerned with modeling the reactor vessel as well as those components of a complete power plant that

427

Fashion Supply Chain Network Competition Ecolabelling  

E-Print Network (OSTI)

, energy, as well as chemicals. For example, it is estimated that cotton uses only 3% of the worldFashion Supply Chain Network Competition with Ecolabelling Anna Nagurney1,2 , Min Yu3 , and Jonas April 2014; revised June 2014 To appear in Sustainable Fashion Supply Chain Management: From Sourcing

Nagurney, Anna

428

Supply Chain Networks: Challenges and Opportunities  

E-Print Network (OSTI)

School of Management University of Massachusetts Amherst, Massachusetts 01003 Department of Management, and consumers at the demand markets. Today, supply chains may span thousands of miles across the globe, involve as the stability and resiliency of supply chains, as well as their adaptability and responsiveness to events

Nagurney, Anna

429

Supply Chain Networks: Challenges and Opportunities  

E-Print Network (OSTI)

School of Management University of Massachusetts Amherst, Massachusetts 01003 Boston INFORMS Chapter and suppliers, distributors, retailers, and consumers at the demand markets. Today, supply chains may span chains, as well as their adaptability and responsiveness to events in a global environment of increasing

Nagurney, Anna

430

Supply Chain Networks: Challenges and Opportunities  

E-Print Network (OSTI)

School of Management University of Massachusetts Amherst, Massachusetts 01003 International Conference of manufacturers and suppliers, distributors, retailers, and consumers at the demand markets. Today, supply chains chains, as well as their adaptability and responsiveness to events in a global environment of increasing

Nagurney, Anna

431

Supply Chains and Transportation Networks Anna Nagurney  

E-Print Network (OSTI)

Management Isenberg School of Management University of Massachusetts Amherst, Massachusetts 01003 December, and consumers at the demand markets. Supply chains are the backbones of our globalized Network Economy of cooperation. For example, in a vertically integrated supply chain the same firm may be responsible

Nagurney, Anna

432

Free Energy of the Antiferromagnetic Linear Chain  

Science Journals Connector (OSTI)

Rigorous upper and lower bounds for the free energy of the antiferromagnetic Heisenberg linear chain are obtained from general convexity properties of the free energy. The lower bound is here derived; the upper bound has been obtained previously by Bulaevskii. Both are compared with the calculations of Bonner and Fisher for finite chains.

Robert B. Griffiths

1964-11-02T23:59:59.000Z

433

Internal Markets for Supply Chain Capacity Allocation  

E-Print Network (OSTI)

Internal Markets for Supply Chain Capacity Allocation David McAdams and Thomas W. Malone Sloan David McAdams & Thomas Malone #12;Internal Markets for Supply Chain Capacity Allocation David Mc ("internal markets") to help allocate manufacturing capacity and determine the prices, delivery dates

434

Double Counting in Supply Chain Carbon Footprinting  

Science Journals Connector (OSTI)

Carbon footprinting is a tool for firms to determine the total greenhouse gas GHG emissions associated with their supply chain or with a unit of final product or service. Carbon footprinting typically aims to identify where best to invest in emission ... Keywords: carbon footprint, emissions allocation, supply chain, sustainable operations

Felipe Caro; Charles J. Corbett; Tarkan Tan; Rob Zuidwijk

2013-10-01T23:59:59.000Z

435

Synthesis, Decay Properties, and Identification of Superheavy Nuclei Produced in {sup 48}Ca-induced Reactions  

SciTech Connect

Thirty-four new nuclides with Z = 104-116, 118 and N = 161-177 have been synthesized in the complete-fusion reactions of {sup 238}U, {sup 237}Np, {sup 242,244}Pu, {sup 243}Am, {sup 245,248}Cm, and {sup 249}Cf targets with {sup 48}Ca beams. The masses of evaporation residues were identified through measurements of the excitation functions of the xn-evaporation channels and from cross bombardments. The decay properties of the new nuclei agree with those of previously known heavy nuclei and with predictions from different theoretical models. A discussion of self-consistent interpretations of all observed decay chains originating from the parent isotopes {sup 282,283}112, {sup 282}113, {sup 286-289}114, {sup 287,288}115, {sup 290-293}116, and {sup 294}118 is presented. Decay energies and lifetimes of the neutron-rich superheavy nuclei as well as their production cross sections indicate a considerable increase in the stability of nuclei with the approach to the theoretically predicted nuclear shells with N = 184 and Z = 114.

Oganessian, Yu. Ts.; Utyonkov, V. K.; Lobanov, Yu. V.; Abdullin, F. Sh.; Polyakov, A. N.; Sagaidak, R. N.; Shirokovsky, I. V.; Tsyganov, Yu. S.; Voinov, A. A.; Iliev, S.; Subbotin, V. G.; Sukhov, A. M.; Gulbekian, G. G.; Bogomolov, S. L.; Gikal, B. N.; Mezentsev, A. N.; Subotic, K.; Zagrebaev, V. I.; Itkis, M. G. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Moody, K. J. [University of California, Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)] (and others)

2007-10-26T23:59:59.000Z

436

Experimental results from CERN on reaction mechanisms in high energy heavy ion collisions  

SciTech Connect

Three main experimental results from CERN concerning reaction mechanisms in high energy heavy ion collisions are discussed: (1) the striking validity of the single particle picture, (2) the nuclear stopping power and (3) the attained energy densities.

Sorensen, S.P. (Oak Ridge National Lab., TN (USA) Tennessee Univ., Knoxville, TN (USA). Dept. of Physics)

1990-01-01T23:59:59.000Z

437

THEOREMES DE BASSE ENERGIE ET REACTIONS PHOTO-PIONIQUES SUR LES NOYAUX J. DELORME, M. ERICSON et A. FIGUREAU  

E-Print Network (OSTI)

. The application of low energy theorems to nuclear photopion reactions in here displayed Various experimental testsTHEOREMES DE BASSE ENERGIE ET REACTIONS PHOTO-PIONIQUES SUR LES NOYAUX J. DELORME, M. ERICSON et A;THEOREMES DE BASSE ENERGIE E T REACTIONS PHOTO-PIONIQUES SUR LES NOYAUX constantes de ccuplage ou facteurs

Boyer, Edmond

438

Nuclear Waste Disposal and Strategies for Predicting Long-Term Performance of Material  

SciTech Connect

Ceramics have been an important part of the nuclear community for many years. On December 2, 1942, an historic event occurred under the West Stands of Stagg Field, at the University of Chicago. Man initiated his first self-sustaining nuclear chain reaction and controlled it. The impact of this event on civilization is considered by many as monumental and compared by some to other significant events in history, such as the invention of the steam engine and the manufacturing of the first automobile. Making this event possible and the successful operation of this first man-made nuclear reactor, was the use of forty tons of UO2. The use of natural or enriched UO2 is still used today as a nuclear fuel in many nuclear power plants operating world-wide. Other ceramic materials, such as 238Pu, are used for other important purposes, such as ceramic fuels for space exploration to provide electrical power to operate instruments on board spacecrafts. Radioisotopic Thermoelectric Generators (RTGs) are used to supply electrical power and consist of a nuclear heat source and converter to transform heat energy from radioactive decay into electrical power, thus providing reliable and relatively uniform power over the very long lifetime of a mission. These sources have been used in the Galileo spacecraft orbiting Jupiter and for scientific investigations of Saturn with the Cassini spacecraft. Still another very important series of applications using the unique properties of ceramics in the nuclear field, are as immobilization matrices for management of some of the most hazardous wastes known to man. For example, in long-term management of radioactive and hazardous wastes, glass matrices are currently in production immobilizing high-level radioactive materials, and cementious forms have also been produced to incorporate low level wastes. Also, as part of nuclear disarmament activities, assemblages of crystalline phases are being developed for immobilizing weapons grade plutonium, to not only produce environmentally friendly products, but also forms that are proliferation resistant. All of these waste forms as well as others, are designed to take advantage of the unique properties of the ceramic systems.

Wicks, G.G.

2001-03-28T23:59:59.000Z

439

Neutron Thermal Cross Sections, Westcott Factors, Resonance Integrals, Maxwellian Averaged Cross Sections and Astrophysical Reaction Rates Calculated from Major Evaluated Data Libraries  

E-Print Network (OSTI)

We present calculations of neutron thermal cross sections, Westcott factors, resonance integrals, Maxwellianaveraged cross sections and astrophysical reaction rates for 843 ENDF materials using data from the major evaluated nuclear libraries and European activation file. Extensive analysis of newly-evaluated neutron reaction cross sections, neutron covariances, and improvements in data processing techniques motivated us to calculate nuclear industry and neutron physics quantities, produce s-process Maxwellian-averaged cross sections and astrophysical reaction rates, systematically calculate uncertainties, and provide additional insights on currently available neutron-induced reaction data. Nuclear reaction calculations are discussed and new results are presented.

Pritychenko, B

2012-01-01T23:59:59.000Z

440

Countering Nuclear Terrorism | National Nuclear Security Administration  

National Nuclear Security Administration (NNSA)

Countering Nuclear Terrorism | National Nuclear Security Administration Countering Nuclear Terrorism | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog The National Nuclear Security Administration Countering Nuclear Terrorism Home > Our Mission > Countering Nuclear Terrorism Countering Nuclear Terrorism NNSA provides expertise, practical tools, and technically informed policy

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Symmetry energy in the structure and in reactions  

E-Print Network (OSTI)

Efforts to extract information on magnitude and density dependence of the nuclear symmetry energy are discussed. The utilized data include those on mass dependence of the excitation energies to the isobaric analog states of ground states, as well as data on the diffusion of isospin in heavy-ion reactions. Results following from different observables are compared.

P. Danielewicz

2010-03-21T23:59:59.000Z

442

Symmetry energy in the structure and in reactions  

E-Print Network (OSTI)

Efforts to extract information on magnitude and density dependence of the nuclear symmetry energy are discussed. The utilized data include those on mass dependence of the excitation energies to the isobaric analog states of ground states, as well as data on the diffusion of isospin in heavy-ion reactions. Results following from different observables are compared.

Danielewicz, P

2010-01-01T23:59:59.000Z

443

Determination of the nuclear level density at high excitation energy  

Science Journals Connector (OSTI)

Evaporation simulations are presented to illustrate the problems associated with the determination of the nuclear level density constant at high excitation energy from evaporation spectra. The methods of using either the total (whole chain) spectra or the difference (from two different initial excitation energies) spectra are discussed. Data from the study of the reaction 701 MeV Si28+100Mo are presented and both methods are used to extract the level density constant. We find that in order to reproduce the slopes of the light particle spectra the level density constant must have a value near 1/10A– 1) / 11 A for excited nuclei with statistical temperatures in the range of 3.5 to 5.5 MeV. This presumes that the only parameter adjustment required to treat the decay of highly exited nuclei is the level density constant. If this is so, the shapes of the evaporation spectra imply a reduction in the level density constant from the value required to explain the decay of less highly excited nuclei, a conclusion reached by others. However, the reduced level density constant leads to an overproduction of deuterons and tritons. This suggests that a more complicated set of parameter adjustments may be required to treat the decay of highly excited nuclei.

A. Chbihi; L. G. Sobotka; N. G. Nicolis; D. G. Sarantites; D. W. Stracener; Z. Majka; D. C. Hensley; J. R. Beene; M. L. Halbert

1991-02-01T23:59:59.000Z

444

From Nucleons To Nuclei To Fusion Reactions  

SciTech Connect

Nuclei are prototypes of many-body open quantum systems. Complex aggregates of protons and neutrons that interact through forces arising from quantum chromo-dynamics, nuclei exhibit both bound and unbound states, which can be strongly coupled. In this respect, one of the major challenges for computational nuclear physics, is to provide a unified description of structural and reaction properties of nuclei that is based on the fundamental underlying physics: the constituent nucleons and the realistic interactions among them. This requires a combination of innovative theoretical approaches and high-performance computing. In this contribution, we present one of such promising techniques, the ab initio no-core shell model/resonating-group method, and discuss applications to light nuclei scattering and fusion reactions that power stars and Earth-base fusion facilities.

Quaglioni, S; Navratil, P; Roth, R; Horiuchi, W

2012-02-15T23:59:59.000Z

445

Alternate Alpha Induced Reactions for NIF Radiochemistry  

SciTech Connect

Radiochemical analysis of NIF capsule residues has been identified as a potential diagnostic of NIF capsule performance. In particular, alpha-induced nuclear reactions that occur on tracer elements added to the NIF capsule have been shown through simulation to be a very sensitive diagnostic for mix. The short range of the alpha particles makes them representative of the hot spot where they are created through the fusion of deuterium and tritium. Reactions on elements doped into the innermost part of the capsule ablator would therefore be sensitive to material that had mixed into the hot spot. Radiochemical determinations of activated detector elements may perhaps be the only true measure of mix that occurs in a NIF capsule, particularly in cases when the capsule fails.

Shaughnessy, D A; Moody, K J; Bernstein, L A

2010-02-26T23:59:59.000Z

446

New cold nuclear fusion theory and experimental tests  

Science Journals Connector (OSTI)

A theory of neutron-induced tritium-deuterium fusion at room temperature is developed, based entirely on previously measured cross-sections of known nuclear reactions. The fusion process involves self-sustaini...

Yeong E. Kim

1990-12-01T23:59:59.000Z

447

Muon catalysis for energy production by nuclear fusion  

Science Journals Connector (OSTI)

... mesic molecular ion (dt?-)+. It takes a short time tf for an exothermic nuclear fusion reaction d + t 4 He-hn to occur. When the probability is tdt, ...

Yu. V. Petrov

1980-06-12T23:59:59.000Z

448

Nuclear Fusion Driven by Coulomb Explosion of Methane Clusters  

Science Journals Connector (OSTI)

Nuclear Fusion Driven by Coulomb Explosion of Methane Clusters† ... However, the distributions obtained for Coulomb explosion lack the high-energy tail manifested for the thermal distribution (Figure 4), which is of considerable importance for thermonuclear reactions. ...

Isidore Last; Joshua Jortner

2002-09-20T23:59:59.000Z

449

Outstanding problems in nuclear astrophysics: recent progress at TRIUMF  

SciTech Connect

Recent experimental and theoretical efforts at TRIUMF on nuclear reactions relevant to big bang nucleosynthesis, quiescent stellar fusion, classical novae, and Type I X-ray bursts are described.

Davids, B., E-mail: davids@triumf.ca [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC (Canada)

2014-04-15T23:59:59.000Z

450

Single-Chain Antibody Library  

DOE Data Explorer (OSTI)

Researchers at Pacific Northwest National Laboratory (PNNL) have constructed a nonimmune library consisting of 109 human antibody scFv fragments, which have been cloned and expressed on the surface of yeast. Nanomolar-affinity scFvs are routinely obtained by magnetic bead screening and flow cytometric sorting. The yeast library can be amplified 1010 fold without measurable loss of clonal diversity. This allows for indefinite expansion of the library. All scFv clones can be assessed directly on the yeast cell surface by immunofluorescent labeling and flow cytometry, obviating separate subcloning, expression, and purification steps. The ability to use multiplex library screening demonstrates the utility of this approach for high-throughput antibody isolation for proteomic applications. The yeast library may be used for research projects or teaching performed for U.S. Government purposes only. If you would like to request an aliquot of the single-chain antibody library for your research, please print and fill out the Materials Transfer Agreement (MTA) [PDF, 20K]. The website provides the contact information for mailing the MTA. [copied from http://www.sysbio.org/dataresources/singlechain.stm

Baird, Cheryl

451

Thermodynamics of multiferroic spin chains  

Science Journals Connector (OSTI)

The minimal model to describe many spin-chain materials with ferroelectric properties is the Heisenberg model with ferromagnetic nearest-neighbor coupling J1 and antiferromagnetic next-nearest-neighbor coupling J2. Here we study the thermodynamics of this model using a density-matrix algorithm applied to transfer matrices. We find that the incommensurate spin-spin correlations—crucial for the ferroelectric properties and the analog of the classical spiral pitch angle—depend not only on the ratio J2/|J1| but also strongly on temperature. We study small easy-plane anisotropies which can stabilize a vector chiral order as well as the finite-temperature signatures of multipolar phases, stable at finite magnetic field. Furthermore, we fit the susceptibilities of LiCuVO4, LiCu2O2, and Li2ZrCuO4. Contrary to the literature, we find that for LiCuVO4 the best fit is obtained with J2?90?K and J2/|J1|?0.5 and show that these values are consistent with the observed spin incommensurability. Finally, we discuss our findings concerning the incommensurate spin-spin correlations and multipolar orders in relation to future experiments on these compounds.

J. Sirker

2010-01-26T23:59:59.000Z

452

Nuclear Data Sheets for A = 230  

SciTech Connect

The evaluators present in this publication spectroscopic data and level schemes from radioactive decay and nuclear reactions for all isobars with mass number A=230. This evaluation includes the first experimental evidence of {sup 230}Am, produced through the {sup 197}Au({sup 40}Ar,3n){sup 234}Bk ({alpha} decay to {sup 230}Am) reaction, E({sup 40}Ar)=188.4 MeV (2003MoZX).

Browne, E.; Tuli, J.K. [National Nuclear Data Center, Brookhaven National Laboratory, Upton, New York 11973-5000 (United States)

2012-08-15T23:59:59.000Z

453

Low energy ($p,?$) reactions in Ni and Cu nuclei using microscopic optical model  

E-Print Network (OSTI)

Radiative capture reactions for low energy protons have been theoretically studied for Ni and Cu isotopes using the microscopic optical model. The optical potential has been obtained in the folding model using different microscopic interactions with the nuclear densities from Relativistic Mean Field calculations. The calculated total cross sections as well as the cross sections for individually low lying levels have been compared with measurements involving stable nuclear targets. Rates for the rapid proton capture process have been evaluated for astrophysically important reactions.

G. Gangopadhyay

2010-08-05T23:59:59.000Z

454

Velocity pump reaction turbine  

DOE Patents (OSTI)

An expanding hydraulic/two-phase velocity pump reaction turbine including a dual concentric rotor configuration with an inter-rotor annular flow channel in which the inner rotor is mechanically driven by the outer rotor. In another embodiment, the inner rotor is immobilized and provided with gas recovery ports on its outer surface by means of which gas in solution may be recovered. This velocity pump reaction turbine configuration is capable of potential energy conversion efficiencies of up to 70%, and is particularly suited for geothermal applications.

House, Palmer A. (Walnut Creek, CA)

1982-01-01T23:59:59.000Z

455

Velocity pump reaction turbine  

DOE Patents (OSTI)

An expanding hydraulic/two-phase velocity pump reaction turbine including a dual concentric rotor configuration with an inter-rotor annular flow channel in which the inner rotor is mechanically driven by the outer rotor. In another embodiment, the inner rotor is immobilized and provided with gas recovery ports on its outer surface by means of which gas in solution may be recovered. This velocity pump reaction turbine configuration is capable of potential energy conversion efficiencies of up to 70%, and is particularly suited for geothermal applications.

House, Palmer A. (Walnut Creek, CA)

1984-01-01T23:59:59.000Z

456

Leading chiral three-nucleon forces along isotope chains in the calcium region  

E-Print Network (OSTI)

Three-nucleon forces (3NFs), and in particular terms of the Fujita-Miyazawa type, strongly influence the structure of neutron-rich exotic isotopes. Ab-initio calculations have shown that chiral two- and three-nucleon interactions correctly reproduce binding energy systematics and neutron driplines of oxygen and nearby isotopes. Exploiting the novel self-consistent Gorkov-Green's function approach, we present the first investigation of Ar, K, Ca, Sc and Ti isotopic chains. Leading chiral 3N interactions are mandatory to reproduce the trend of binding energies throughout these chains and to obtain a good description of two-neutron separation energies. At the same time, nuclei in this mass region are systematically overbound by about 40 MeV and the $N=20$ magic gap is significantly overestimated. We conclude that ab-initio many-body calculations of mid-mass isotopic chains challenge modern theories of elementary nuclear interactions.

V. Somà; A. Cipollone; C. Barbieri; P. Navrátil; T. Duguet

2013-12-07T23:59:59.000Z

457

Ion-induced nuclear radiotherapy  

DOE Patents (OSTI)

Ion-induced Nuclear Radiotherapy (INRT) is a technique for conducting radiosurgery and radiotherapy with a very high degree of control over the spatial extent of the irradiated volume and the delivered dose. Based upon the concept that low energy, ion induced atomic and nuclear reactions can be used to produce highly energetic reaction products at the site of a tumor, the INRT technique is implemented through the use of a conduit-needle or tube which conducts a low energy ion beam to a position above or within the intended treatment area. At the end of the conduit-needle or tube is a specially fabricated target which, only when struck by the ion beam, acts as a source of energetic radiation products. The inherent limitations in the energy, and therefore range, of the resulting reaction products limits the spatial extent of irradiation to a pre-defined volume about the point of reaction. Furthermore, since no damage is done to tissue outside this irradiated volume, the delivered dose may be made arbitrarily large. INRT may be used both as a point-source of radiation at the site of a small tumor, or as a topical bath of radiation to broad areas of diseased tissue.

Horn, Kevin M. (Albuquerque, NM); Doyle, Barney L. (Albuquerque, NM)

1996-01-01T23:59:59.000Z

458

Ion-induced nuclear radiotherapy  

DOE Patents (OSTI)

Ion-induced Nuclear Radiotherapy (INRT) is a technique for conducting radiosurgery and radiotherapy with a very high degree of control over the spatial extent of the irradiated volume and the delivered dose. Based upon the concept that low energy, ion induced atomic and nuclear reactions can be used to produce highly energetic reaction products at the site of a tumor, the INRT technique is implemented through the use of a conduit-needle or tube which conducts a low energy ion beam to a position above or within the intended treatment area. At the end of the conduit-needle or tube is a specially fabricated target which, only when struck by the ion beam, acts as a source of energetic radiation products. The inherent limitations in the energy, and therefore range, of the resulting reaction products limits the spatial extent of irradiation to a pre-defined volume about the point of reaction. Furthermore, since no damage is done to tissue outside this irradiated volume, the delivered dose may be made arbitrarily large. INRT may be used both as a point-source of radiation at the site of a small tumor, or as a topical bath of radiation to broad areas of diseased tissue. 25 figs.

Horn, K.M.; Doyle, B.L.

1996-08-20T23:59:59.000Z

459

Solid state laser media driven by remote nuclear powered fluorescence  

DOE Patents (OSTI)

An apparatus is provided for driving a solid state laser by a nuclear powered fluorescence source which is located remote from the fluorescence source. A nuclear reaction produced in a reaction chamber generates fluorescence or photons. The photons are collected from the chamber into a waveguide, such as a fiber optic waveguide. The waveguide transports the photons to the remote laser for exciting the laser.

Prelas, Mark A. (Columbia, MO)

1992-01-01T23:59:59.000Z

460

Strong plasma screening in thermonuclear reactions: Electron drop model  

Science Journals Connector (OSTI)

We analyze enhancement of thermonuclear fusion reactions due to strong plasma screening in dense matter using a simple electron drop model. In the model we assume fusion in a potential that is screened by an effective electron cloud around colliding nuclei (extended Salpeter ion-sphere model). We calculate the mean-field screened Coulomb potentials for atomic nuclei with equal and nonequal charges, appropriate astrophysical S factors, and enhancement factors of reaction rates. As a byproduct, we study the analytic behavior of the screening potential at small separations between the reactants. In this model, astrophysical S factors depend not only on nuclear physics but on plasma screening as well. The enhancement factors are in good agreement with calculations by other methods. This allows us to formulate a combined, pure analytic model of strong plasma screening in thermonuclear reactions. The results can be useful for simulating nuclear burning in white dwarfs and neutron stars.

P. A. Kravchuk and D. G. Yakovlev

2014-01-09T23:59:59.000Z

Note: This page contains sample records for the topic "nuclear chain reaction" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Strong plasma screening in thermonuclear reactions: Electron drop model  

E-Print Network (OSTI)

We analyze enhancement of thermonuclear fusion reactions due to strong plasma screening in dense matter using a simple electron drop model. The model assumes fusion in a potential that is screened by an effective electron cloud around colliding nuclei (extended Salpeter ion-sphere model). We calculate the mean field screened Coulomb potentials for atomic nuclei with equal and nonequal charges, appropriate astrophysical S factors, and enhancement factors of reaction rates. As a byproduct, we study analytic behavior of the screening potential at small separations between the reactants. In this model, astrophysical S factors depend not only on nuclear physics but on plasma screening as well. The enhancement factors are in good agreement with calculations by other methods. This allows us to formulate the combined, pure analytic model of strong plasma screening in thermonuclear reactions. The results can be useful for simulating nuclear burning in white dwarfs and neutron stars.

Kravchuk, P A

2014-01-01T23:59:59.000Z

462

Strong plasma screening in thermonuclear reactions: Electron drop model  

E-Print Network (OSTI)

We analyze enhancement of thermonuclear fusion reactions due to strong plasma screening in dense matter using a simple electron drop model. The model assumes fusion in a potential that is screened by an effective electron cloud around colliding nuclei (extended Salpeter ion-sphere model). We calculate the mean field screened Coulomb potentials for atomic nuclei with equal and nonequal charges, appropriate astrophysical S factors, and enhancement factors of reaction rates. As a byproduct, we study analytic behavior of the screening potential at small separations between the reactants. In this model, astrophysical S factors depend not only on nuclear physics but on plasma screening as well. The enhancement factors are in good agreement with calculations by other methods. This allows us to formulate the combined, pure analytic model of strong plasma screening in thermonuclear reactions. The results can be useful for simulating nuclear burning in white dwarfs and neutron stars.

P. A. Kravchuk; D. G. Yakovlev

2014-01-11T23:59:59.000Z

463

Nuclear models relevant to evaluation  

SciTech Connect

The widespread use of nuclear models continues in the creation of data evaluations. The reasons include extension of data evaluations to higher energies, creation of data libraries for isotopic components of natural materials, and production of evaluations for radiative target species. In these cases, experimental data are often sparse or nonexistent. As this trend continues, the nuclear models employed in evaluation work move towards more microscopically-based theoretical methods, prompted in part by the availability of increasingly powerful computational resources. Advances in nuclear models applicable to evaluation will be reviewed. These include advances in optical model theory, microscopic and phenomenological state and level density theory, unified models that consistently describe both equilibrium and nonequilibrium reaction mechanism, and improved methodologies for calculation of prompt radiation from fission. 84 refs., 8 figs.

Arthur, E.D.; Chadwick, M.B.; Hale, G.M.; Young, P.G.

1991-01-01T23:59:59.000Z

464

Learning Nuclear Science with Marbles  

Science Journals Connector (OSTI)

Nuclei are small: if an atom was the size of a football field the nucleus would be an apple sitting on the 50?yd line. At the same time nuclei are dense: the Earth compressed to nuclear density could fit inside four Sears Towers. The subatomic level is strange and exotic. For that reason it's not hard to get young minds excited about nuclear science. But how does one move beyond analogies like those above and offer a better understanding of the extraordinary world of the nucleus? This is the challenge faced by the outreach program at Michigan State University's National Superconducting Cyclotron Laboratory (NSCL) a National Science Foundation?supported facility specializing in the creation and study of rare isotopes. It was necessary to devise a model of the nucleus that students could interact with and even use to approximate the nuclear reactions that create exotic nuclei. The solution was to use magnetic marbles.

Zach Constan

2010-01-01T23:59:59.000Z

465

The AMEDEE Nuclear Structure Database  

SciTech Connect

The increasing need for nuclear data far from the valley of stability requires information on nuclei which cannot be accessed experimentally or for which almost no experimental data is known. Consequently, the use of microscopic approaches to predict properties of such poorly known nuclei is necessary as a first step to improve our understanding of nuclear reaction on exotic nuclei. Within this context, large scale axial mean field calculations from proton to neutron drip-lines have been performed using the Hartree-Fock-Bogoliubov method based on the DIS Gogny nucleon-nucleon effective interaction. Nearly 7000 nuclei have been studied under the axial symmetry hypothesis and several properties are now available for the nuclear scientific community on an Internet web site for every individual nucleus.

Hilaire, S.; Girod, M. [CEA/DAM Ile-de-France, Service de Physique Nucleaire, BP 12, F-91680 Bruyeres-le-Chatel (France)

2008-05-12T23:59:59.000Z

466

Structure of Human Ferritin L Chain  

SciTech Connect

Ferritin is the major iron-storage protein present in all cells. It generally contains 24 subunits, with different ratios of heavy chain (H) to light chain (L), in the shape of a hollow sphere hosting up to 4500 ferric Fe atoms inside. H-rich ferritins catalyze the oxidation of iron(II), while L-rich ferritins promote the nucleation and storage of iron(III). Several X-ray structures have been determined, including those of L-chain ferritins from horse spleen (HoSF), recombinant L-chain ferritins from horse (HoLF), mouse (MoLF) and bullfrog (BfLF) as well as recombinant human H-chain ferritin (HuHF). Here, structures have been determined of two crystal forms of recombinant human L-chain ferritin (HuLF) obtained from native and perdeuterated proteins. The structures show a cluster of acidic residues at the ferrihydrite nucleation site and at the iron channel along the threefold axis. An ordered Cd{sup 2+} structure is observed within the iron channel, offering further insight into the route and mechanism of iron transport into the capsid. The loop between helices D and E, which is disordered in many other L-chain structures, is clearly visible in these two structures. The crystals generated from perdeuterated HuLF will be used for neutron diffraction studies.

Wang,Z.; Li, C.; Ellenburg, M.; Soistman, E.; Ruble, J.; Wright, B.; Ho, J.; Carter, D.

2006-01-01T23:59:59.000Z

467

Reaction product imaging  

SciTech Connect

Over the past few years the author has investigated the photochemistry of small molecules using the photofragment imaging technique. Bond energies, spectroscopy of radicals, dissociation dynamics and branching ratios are examples of information obtained by this technique. Along with extending the technique to the study of bimolecular reactions, efforts to make the technique as quantitative as possible have been the focus of the research effort. To this end, the author has measured the bond energy of the C-H bond in acetylene, branching ratios in the dissociation of HI, the energetics of CH{sub 3}Br, CD{sub 3}Br, C{sub 2}H{sub 5}Br and C{sub 2}H{sub 5}OBr dissociation, and the alignment of the CD{sub 3} fragment from CD{sub 3}I photolysis. In an effort to extend the technique to bimolecular reactions the author has studied the reaction of H with HI and the isotopic exchange reaction between H and D{sub 2}.

Chandler, D.W. [Sandia National Laboratories, Livermore, CA (United States)

1993-12-01T23:59:59.000Z

468

Ion-Molecule Reactions  

Science Journals Connector (OSTI)

...de-gree of agreement between theory and experiment is achieved from...criticisms, how-ever, the theory of the orbiting complex appears...rigorous description of the basic physics of the reaction com-plex. Most criticisms of the theory should more properly be addressed...

J. H. Futrell; T. O. Tiernan

1968-10-25T23:59:59.000Z

469

Near and sub-barrier fusion as a probe of nuclear structure Sub-barrier fusion is particularly sensitive to the tail of the nuclear matter distribution,  

E-Print Network (OSTI)

Near and sub-barrier fusion as a probe of nuclear structure Sub-barrier fusion is particularly sensitive to the tail of the nuclear matter distribution, hence provides a good probe of the neutron and proton distributions. Measuring fusion for an isotopic chain of projectile nuclei one can sensitively

de Souza, Romualdo T.

470

Nuclear spin and isospin excitations  

Science Journals Connector (OSTI)

A review is given of our present knowledge of collective spin-isospin excitations in nuclei. Most of this knowledge comes from intermediate-energy charge-exchange reactions and from inelastic electron- and proton-scattering experiments. The nuclear-spin dynamics is governed by the spin-isospin-dependent two-nucleon interaction in the medium. This interaction gives rise to collective spin modes such as the giant Gamow-Teller resonances. An interesting phenomenon is that the measured total Gamow-Teller transition strength in the resonance region is much less than a model-independent sum rule predicts. Two physically different mechanisms have been discussed to explain this so-called quenching of the total Gamow-Teller strength: coupling to subnuclear degrees of freedom in the form of ?-isobar excitation and ordinary nuclear configuration mixing. Both detailed nuclear structure calculations and extensive analyses of the scattering data suggest that the nuclear configuration mixing effect is the more important quenching mechanism, although subnuclear degrees of freedom cannot be ruled out. The quenching phenomenon occurs for nuclear-spin excitations at low excitation energies (??10-20 MeV) and small-momentum transfers (q?0.5 fm-1). A completely opposite effect is anticipated in the high (?, q)-transfer region (0???500 MeV, 0.5?q?3 fm-1). The nuclear spin-isospin response might be enhanced due to the attractive pion field inside the nucleus. Charge-exchange reactions at GeV incident energies have been used to study the quasifree peak region and the ?-resonance region. An interesting result of these experiments is that the ? excitation in the nucleus is shifted downwards in energy relative to the ? excitation of the free proton. The physical origin of this shift is discussed, and it is shown that it may be related to the energy-dependent, attractive one-pion exchange interaction in the medium.

Franz Osterfeld

1992-04-01T23:59:59.000Z

471

Nuclear Induction  

Science Journals Connector (OSTI)

The magnetic moments of nuclei in normal matter will result in a nuclear paramagnetic polarization upon establishment of equilibrium in a constant magnetic field. It is shown that a radiofrequency field at right angles to the constant field causes a forced precession of the total polarization around the constant field with decreasing latitude as the Larmor frequency approaches adiabatically the frequency of the r-f field. Thus there results a component of the nuclear polarization at right angles to both the constant and the r-f field and it is shown that under normal laboratory conditions this component can induce observable voltages. In Section 3 we discuss this nuclear induction, considering the effect of external fields only, while in Section 4 those modifications are described which originate from internal fields and finite relaxation times.

F. Bloch

1946-10-01T23:59:59.000Z

472

Collaborating Organizations - Nuclear Data Program, Nuclear Engineering  

NLE Websites -- All DOE Office Websites (Extended Search)

Collaborating Organizations Collaborating Organizations Nuclear Data Program Overview Current Projects & Recent Activities Collaborating Organizations Publications Nuclear Data Measurements (NDM) Reports Experimental Nuclear Data Resources Contact ND Program Related Resources Other Major Programs Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE Division on Flickr Nuclear Data Program Collaborating Organizations Bookmark and Share National Nuclear Data Center, Brookhaven National Laboratory, Upton, New York. International Nuclear Structure and Decay Data Network, coordinated by IAEA, Vienna, Austria Heavy-Ion Nuclear Physics Group, Physics Division, Argonne National Laboratory, Argonne, Illinois. Nuclear Spectroscopy Group, Department of Nuclear Physics,

473

An engineering approach to improving hospital supply chains  

E-Print Network (OSTI)

This thesis explores supply chain management practices that have been implemented, and have improved supply chains in industries outside of healthcare. The presented supply chain practices have been selected because they ...

Cheng, Scott Hsiang-Jen

2008-01-01T23:59:59.000Z

474

Criticality without Frustration for Quantum Spin-1 Chains  

E-Print Network (OSTI)

Frustration-free (FF) spin chains have a property that their ground state minimizes all individual terms in the chain Hamiltonian. We ask how entangled the ground state of a FF quantum spin-s chain with nearest-neighbor ...

Movassagh, Ramis

475

Impact of demographics on supply chain risk management practices  

E-Print Network (OSTI)

Do demographic factors play a role in the choice of supply chain risk management practices by supply chain professionals? Are there stronger relationships between certain demographic factors and supply chain risk management ...

Kanyagui, Kenneth (Kenneth K.)

2010-01-01T23:59:59.000Z

476

Reaction studies of hot silicon, germanium and carbon atoms  

SciTech Connect

The goal of this project was to increase the authors understanding of the interplay between the kinetic and electronic energy of free atoms and their chemical reactivity by answering the following questions: (1) what is the chemistry of high-energy carbon silicon and germanium atoms recoiling from nuclear transformations; (2) how do the reactions of recoiling carbon, silicon and germanium atoms take place - what are the operative reaction mechanisms; (3) how does the reactivity of free carbon, silicon and germanium atoms vary with energy and electronic state, and what are the differences in the chemistry of these three isoelectronic atoms This research program consisted of a coordinated set of experiments capable of achieving these goals by defining the structures, the kinetic and internal energy, and the charge states of the intermediates formed in the gas-phase reactions of recoiling silicon and germanium atoms with silane, germane, and unsaturated organic molecules, and of recoiling carbon atoms with aromatic molecules. The reactions of high energy silicon, germanium, and carbon atoms created by nuclear recoil were studied with substrates chosen so that their products illuminated the mechanism of the recoil reactions. Information about the energy and electronic state of the recoiling atoms at reaction was obtained from the variation in end product yields and the extent of decomposition and rearrangement of primary products (usually reactive intermediates) as a function of total pressure and the concentration of inert moderator molecules that remove kinetic energy from the recoiling atoms and can induce transitions between electronic spin states. 29 refs.

Gaspar, P.P.

1990-11-01T23:59:59.000Z

477

Scattering and reaction cross-sections measured at SPES I Results compiled by  

E-Print Network (OSTI)

for low energy nuclear physics measurements i.e. : diffe- rential cross-section (a = deT/dQ) versus This article gives all the differential cross-sections for two body reactions at intermediate energy measured (Saclay) in 1971 in order to investigate intermediate energy two body reactions. This magne- tic

Boyer, Edmond

478

The New SuperORRUBA Detector for Transfer Reaction Studies of Exotic Nuclei  

E-Print Network (OSTI)

(inverse kinematics) [4, 5]. The ejected protons from such reactions carry the nuclear spectroscopic of the extreme inverse nature of the reaction, the proton energy rapidly changes as a function of laboratory is also required because of the relatively low intensity of exotic beams. Figure 1: Expected energies

479

Nuclear Science & Technology  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Science & Technology Nuclear Science & Technology Nuclear Science & Technology1354608000000Nuclear Science & TechnologySome of these resources are LANL-only and will require Remote Access. /No/ Nuclear Science & Technology Some of these resources are LANL-only and will require Remote Access. Key Resources Databases Organizations Journals Key Resources International Atomic Energy Agency IAEA scientific and technical publications cover areas of nuclear power, radiation therapy, nuclear security, nuclear law, and emergency repose. Search under Publications/Books and Reports for scientific books, standards, technical guides and reports National Nuclear Data Center Nuclear physics data for basic nuclear research and for applied nuclear technologies, operated by Brookhaven.

480

NUCLEAR PROXIMITY FORCES  

E-Print Network (OSTI)

One might summarize of nuclear potential energy has beendegree of freedom) for the nuclear interaction between anyUniversity of California. Nuclear Proximity Forces 'I< at

Randrup, J.

2011-01-01T23:59:59.000Z

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481

Nuclear Nonproliferation Programs | ORNL  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Nonproliferation Programs SHARE Nuclear Nonproliferation Programs image Oak Ridge National Laboratory covers the entire spectrum of nuclear nonproliferation work, from...

482

The role of chemical reactions in the Chernobyl accident  

SciTech Connect

It is shown that chemical reactions played an essential role in the Chernobyl accident at all of its stages. It is important that the reactor before the explosion was at maximal xenon poisoning, and its reactivity, apparently, was not destroyed by the explosion. The reactivity release due to decay of Xe-235 on the second day after the explosion led to a reactor power of 80-110 MW. Owing to this power, the chemical reactions of reduction of uranium, plutonium, and other metals at a temperature of about 2000 Degree-Sign C occurred in the core. The yield of fission products thus sharply increased. Uranium and other metals flew down in the bottom water communications and rooms. After reduction of the uranium and its separation from the graphite, the chain reaction stopped, the temperature of the core decreased, and the activity yield stopped.

Grishanin, E. I., E-mail: egrishanin@orexovo.net [Russian Research Center Kurchatov Institute (Russian Federation)

2010-12-15T23:59:59.000Z

483

Nuclear Data | More Science | ORNL  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Data SHARE Nuclear Data Nuclear Data ORNL is a recognized, international leader in nuclear data research and development (R&D) to support nuclear applications analyses. For...

484

Nuclear Facilities | Department of Energy  

Energy Savers (EERE)

Nuclear Facilities Nuclear Facilities Nuclear Facilities Locator Map Numerical map data points indicate two or more nuclear facilities in the same geographic location. Nuclear...

485

Nuclear Data Evaluations for Americium Isotopes  

SciTech Connect

Recent upgrades of 241Am, 242mAm, and 240Am nuclear data in the keV - 30-MeV range are described. The new evaluation takes advantage of recent measurements and advances in calculational modeling methods. The model calculations are especially important for the nuclear data of americium isotopes, because few measurements are available. The nuclear-model code GNASH is extensively used for our evaluations. The new evaluations are given for total, fission, capture (n, 2n), and (n, 3n) reaction cross sections, and vp for 241Am and 242mAm. A new evaluation for 240Am is also given by expanding our modeling feasibility.

Kawano, T.; Talou, P.; Chadwick, M.B.; MacFarlane, R.E.; Young, P.G. [T-16 Nuclear Physics, Los Alamos National Laboratory (United States)

2005-05-24T23:59:59.000Z

486

Characterization of Crude Oil Products Using Data Fusion of Process Raman, Infrared, and Nuclear Magnetic Resonance (NMR) Spectra  

Science Journals Connector (OSTI)

Process Raman, infrared (IR), and nuclear magnetic resonance (NMR) analyses are currently being performed in industrial settings for the monitoring of large scale reactions. These...

Dearing, Thomas I; Thompson, Wesley J; Rechsteiner, Carl E; Marquardt, Brian J

2011-01-01T23:59:59.000Z

487

Multiperiod Competitive Supply Chain Networks with Inventorying and A Transportation Network Equilibrium Reformulation Multiperiod Competitive Supply Chain Networks  

E-Print Network (OSTI)

Multiperiod Competitive Supply Chain Networks with Inventorying and A Transportation Network Equilibrium Reformulation Multiperiod Competitive Supply Chain Networks with Inventorying and A Transportation Competitive Supply Chain Networks with Inventorying and A Transportation Network Equilibrium Reformulation

Nagurney, Anna

488

U.S. Offshore Wind Manufacturing and Supply Chain Development...  

Office of Environmental Management (EM)

U.S. Offshore Wind Manufacturing and Supply Chain Development U.S. Offshore Wind Manufacturing and Supply Chain Development This report seeks to provide an organized, analytical...

489

Initiative in Nuclear Theory at the Variable Energy Cyclotron Centre  

E-Print Network (OSTI)

We recall the path breaking contributions of the nuclear theory group of the Variable Energy Cyclotron Centre, Kolkata. From a beginning of just one person in 1970s, the group has steadily developed into a leading group in the country today, with seminal contributions to almost the entire range of nuclear physics, viz., low energy nuclear reactions, nuclear structure, deep inelastic collisions, fission, liquid to gas phase transitions, nuclear matter, equation of state, mass formulae, neutron stars, relativistic heavy ion collisions, medium modification of hadron properties, quark gluon plasma, and cosmology of early universe.

D. K. Srivastava; J. Alam; D. N. Basu; A. K. Chaudhuri; J. N. De; K. Krishan; S. Pal

2005-06-24T23:59:59.000Z

490

Multiconfiguration Resonating-Group Study of Nuclear Reaction Mechanisms  

Science Journals Connector (OSTI)

......heavy-weight systems. With the findings...obtained from these studies, it is our opinion...Resonating-Group Study of the 10-Nucleon System Yoshikazu Fujiwara...References 1) Wheeler J. A. Phys...APS] . 43) Foster D. G. Jr......

Yoshikazu Fujiwara; Y.C. Tang

1994-04-01T23:59:59.000Z

491

Nuclear Fission: Reaction to the Discovery in 1939  

E-Print Network (OSTI)

U-235. As is well known, Glenn Seaborg soon discovered thisinformal and formal. Glenn Seaborg remembered " a seminar in

Hodes, Elizabeth; Tiddens, Adolph; Badash, Lawrence

1985-01-01T23:59:59.000Z

492

Subthreshold K+ production in deuteron and alpha induced nuclear reactions  

E-Print Network (OSTI)

Double differential cross sections have been measured for pi+ and K+ emitted around midraidity in d+A and He+A collisions at a beam kinetic energy of 1.15 GeV/nucleon. The total pi+ yield increases by a factor of about 2 when using an alpha projectile instead of a deuteron whereas the K+ yield increases by a factor of about 4. According to transport calculations, the K+ enhancement depends both on the number of hadron-hadron collisions and on the energy available in those collisions: their center-of-mass energy increases with increasing number of projectile nucleons.

M. Debowski; P. Senger; M. Boivin; Y. LeBornec; P. Courtat; R. Gacougnolle; E. Grosse; S. Kabana; T. Kirchner; P. Koczon; M. Mang; E. Schwab; B. Tatischeff; A. Wagner; W. Walus; N. Willis; G. Wolf; R. Wurzinger; J. Yonnet

1997-09-10T23:59:59.000Z

493

A quantum statistical model of nuclear fragmentation reactions  

E-Print Network (OSTI)

are tallied from left to right. The numbering system is illustrated in Figure 1. This scheme was also very useful to the storage and referencing of nuclidic information such as mass and half-life data within the computer programs that were used... computer memory, given the proton and neutron numbers of each product. Using a special refer- 14 encing system , a minimal amount of core storage space for this data is needed. When the channel phase space is found for each incident energy...

Gruben, James Henry

2012-06-07T23:59:59.000Z

494

Segmentation strategies for managing retail supply chains  

E-Print Network (OSTI)

High-technology manufacturing companies often face rapid price decline and capacity constraints. Especially in the retail side of the business where the supply chain is much longer and revenue is sometimes not recognized ...

Liang, Catherine G. (Catherine Gloria)

2011-01-01T23:59:59.000Z

495

Supply chain and the executive agenda  

E-Print Network (OSTI)

In recent years, supply chain pundits and consultants emphasized the importance of strategies such as just-in-time, lean manufacturing, off- shoring or frequent deliveries to retail outlets. However, with significant ...

Peruvankal, James Paul

2011-01-01T23:59:59.000Z

496

Economic analysis of the meat supply chain  

E-Print Network (OSTI)

and overseas animal disease outbreaks on the Korean meat supply chain. Market impacts are investigated using both forecasts and historical decomposition of price innovations based on an error correction model (ECM) of the Korean meat sector. Results indicate...

Park, Moon-Soo

2009-05-15T23:59:59.000Z

497

The supply chain response to environmental pressures  

E-Print Network (OSTI)

Understanding and shaping the relationship between supply chain management and the natural environment is critical not only to human health and the environment, but to the future success of business. While the cumulative ...

Paquette, Julie Rebecca

2006-01-01T23:59:59.000Z

498

Free Energy of Multiple Overlapping Chains  

Science Journals Connector (OSTI)

How accurate is pair additivity in describing interactions between soft polymer-based nanoparticles? Using numerical simulations we compute the free energy cost required to overlap multiple chains in the same region of space, and provide a quantitative measure of the effectiveness of pair additivity as a function of chain number and length. Our data suggest that pair additivity can indeed become quite inadequate as the chain density in the overlapping region increases. We also show that even a scaling theory based on polymer confinement can only partially account for the complexity of the problem. In fact, we unveil and characterize an isotropic to star-polymer crossover taking place for large number of chains, and propose a revised scaling theory that better captures the physics of the problem.

Katherine Klymko and Angelo Cacciuto

2011-12-27T23:59:59.000Z

499

Internal Markets for Supply Chain Capacity Allocation  

E-Print Network (OSTI)

This paper explores the possibility of solving supply chain capacity allocation problems using internal markets among employees of the same company. Unlike earlier forms of transfer pricing, IT now makes it easier for such ...

McAdams, David

2005-07-08T23:59:59.000Z

500

Ethylene detection in fruit supply chains  

Science Journals Connector (OSTI)

...Steffen Janssen and Walter Lang Ethylene detection in fruit supply chains S...and advanced warehouse management . Ethylene is a gaseous ripening phytohormone of fruits and plants. Presently, ethylene is primarily measured with stationary...

2014-01-01T23:59:59.000Z