Investigation of the feasibility of a small scale transmutation device

NASA Astrophysics Data System (ADS)

Sit, Roger Carson

This dissertation presents the design and feasibility of a small-scale, fusion-based transmutation device incorporating a commercially available neutron generator. It also presents the design features necessary to optimize the device and render it practical for the transmutation of selected long-lived fission products and actinides. Four conceptual designs of a transmutation device were used to study the transformation of seven radionuclides: long-lived fission products (Tc-99 and I-129), short-lived fission products (Cs-137 and Sr-90), and selective actinides (Am-241, Pu-238, and Pu-239). These radionuclides were chosen because they are major components of spent nuclear fuel and also because they exist as legacy sources that are being stored pending a decision regarding their ultimate disposition. The four designs include the use of two different devices; a Deuterium-Deuterium (D-D) neutron generator (for one design) and a Deuterium-Tritium (D-T) neutron generator (for three designs) in configurations which provide different neutron energy spectra for targeting the radionuclide for transmutation. Key parameters analyzed include total fluence and flux requirements; transmutation effectiveness measured as irradiation effective half-life; and activation products generated along with their characteristics: activity, dose rate, decay, and ingestion and inhalation radiotoxicity. From this investigation, conclusions were drawn about the feasibility of the device, the design and technology enhancements that would be required to make transmutation practical, the most beneficial design for each radionuclide, the consequence of the transmutation, and radiation protection issues that are important for the conceptual design of the transmutation device. Key conclusions from this investigation include: (1) the transmutation of long-lived fission products and select actinides can be practical using a small-scale, fusion driven transmutation device; (2) the transmutation of long

Transmutation Theory in the Greek Alchemical Corpus.

PubMed

Dufault, Olivier

2015-08-01

This paper studies transmutation theory as found in the texts attributed to Zosimus of Panopolis, "the philosopher Synesius," and "the philosopher Olympiodorus of Alexandria." It shows that transmutation theory (i.e. a theory explaining the complete transformation of substances) is mostly absent from the work attributed to these three authors. The text attributed to Synesius describes a gilding process, which is similar to those described by Pliny and Vitruvius. The commentary attributed to Olympiodorus is the only text studied here that describes something similar to a transmutation theory. It is unclear, however, if this was a theory of transmutation or if the writer meant something more like the literal meaning of the word "ekstrophē," a term used to describe the transformation of metals, as the "turning inside-out" of what is hidden in a substance. A similar conception of ekstrophē can be found in the works of Zosimus, who discussed transmutation to make an analogy with self-purification processes, which, from the perspective of his own anthropogony, consisted in the "turning inside-out" of the "inner human" (esō anthrōpos).

Copper Doping of Zinc Oxide by Nuclear Transmutation

DTIC Science & Technology

2014-03-27

Copper Doping of Zinc Oxide by Nuclear Transmutation THESIS Matthew C. Recker, Captain, USAF AFIT-ENP-14-M-30 DEPARTMENT OF THE AIR FORCE AIR...NUCLEAR TRANSMUTATION THESIS Presented to the Faculty Department of Engineering Physics Graduate School of Engineering and Management Air Force...COPPER DOPING OF ZINC OXIDE BY NUCLEAR TRANSMUTATION Matthew C. Recker, BS Captain, USAF Approved: //signed// 27 February 2014 John W. McClory, PhD

(n,xn) cross section measurements for Y-89 foils used as detectors for high energy neutron measurements in the deeply subcritical assembly "QUINTA"

NASA Astrophysics Data System (ADS)

Bielewicz, Marcin; Kilim, Stanisław; Strugalska-Gola, Elżbieta; Szuta, Marcin; Wojciechowski, Andrzej; Tyutyunnikov, Sergey; Prokofiev, Alexander; Passoth, Elke

2017-09-01

Study of the deep subcritical systems (QUINTA) using relativistic beams is performed within the project "Energy and Transmutation of Radioactive Wastes" (E&T - RAW). The experiment assembly was irradiated by deuteron/proton beam (Dubna NUCLOTRON). We calculated the neutron energy spectrum inside the whole assembly by using threshold energy (n,xn) reactions in yttrium (Y-89) foils. There are almost no experimental cross section data for those reactions. New Y-89(n,xn) cross section measurements were carried out at The Svedberg laboratory (TSL) in Uppsala, Sweden in 2015. In this paper we present preliminary results of those experiments.

Validation of PHITS Spallation Models from the Perspective of the Shielding Design of Transmutation Experimental Facility

NASA Astrophysics Data System (ADS)

Iwamoto, Hiroki; Meigo, Shin-ichiro

2017-09-01

The impact of different spallation models implemented in the particle transport code PHITS on the shielding design of Transmutation Experimental Facility is investigated. For 400-MeV proton incident on a lead-bismuth eutectic target, an effective dose rate at the end of a thick radiation shield (3-m-thick iron and 3-m-thick concrete) calculated by the Liège intranuclear cascade (INC) model version 4.6 (INCL4.6) coupled with the GEMcode (INCL4.6/GEM) yields about twice as high as the Bertini INC model (Bertini/GEM). A comparison with experimental data for 500-MeV proton incident on a thick lead target suggest that the prediction accuracy of INCL4.6/GEM would be better than that of Bertini/GEM. In contrast, it is found that the dose rates in beam ducts in front of targets calculated by the INCL4.6/GEMare lower than those by the Bertini/GEM. Since both models underestimate the experimental results for neutron-production doubledifferential cross sections at 180° for 140-MeV proton incident on carbon, iron, and gold targets, it is concluded that it is necessary to allow a margin for uncertainty caused by the spallation models, which is a factor of two, in estimating the dose rate induced by neutron streaming through a beam duct.

Fast reactor core concepts to improve transmutation efficiency

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fujimura, Koji; Kawashima, Katsuyuki; Itooka, Satoshi

Fast Reactor (FR) core concepts to improve transmutation efficiency were conducted. A heterogeneous MA loaded core was designed based on the 1000MWe-ABR breakeven core. The heterogeneous MA loaded core with Zr-H loaded moderated targets had a better transmutation performance than the MA homogeneous loaded core. The annular pellet rod design was proposed as one of the possible design options for the MA target. It was shown that using annular pellet MA rods mitigates the self-shielding effect in the moderated target so as to enhance the transmutation rate.

Accelerator-driven transmutation of spent fuel elements

DOEpatents

Venneri, Francesco; Williamson, Mark A.; Li, Ning

2002-01-01

An apparatus and method is described for transmuting higher actinides, plutonium and selected fission products in a liquid-fuel subcritical assembly. Uranium may also be enriched, thereby providing new fuel for use in conventional nuclear power plants. An accelerator provides the additional neutrons required to perform the processes. The size of the accelerator needed to complete fuel cycle closure depends on the neutron efficiency of the supported reactors and on the neutron spectrum of the actinide transmutation apparatus. Treatment of spent fuel from light water reactors (LWRs) using uranium-based fuel will require the largest accelerator power, whereas neutron-efficient high temperature gas reactors (HTGRs) or CANDU reactors will require the smallest accelerator power, especially if thorium is introduced into the newly generated fuel according to the teachings of the present invention. Fast spectrum actinide transmutation apparatus (based on liquid-metal fuel) will take full advantage of the accelerator-produced source neutrons and provide maximum utilization of the actinide-generated fission neutrons. However, near-thermal transmutation apparatus will require lower standing

Dimensional Transmutation by Monopole Condensation in QCD

NASA Astrophysics Data System (ADS)

Cho, Y. M.

2015-01-01

The dimensional transmutation by the monopole condensation in QCD is reviewed. Using Abelian projection of the gauge potential which projects out the monopole potential gauge independently, we we show that there are two types of gluons: the color neutral binding gluons which plays the role of the confining agent and the colored valence gluons which become confined prisoners. With this we calculate the one-loop QCD effective potential and show the monopole condensation becomes the true vacuum of QCD. We propose to test the existence of two types of gluons experimentally by re-analyzing the existing gluon jets data.

Transmutation of Matter in Byzantium: The Case of Michael Psellos, the Alchemist

NASA Astrophysics Data System (ADS)

Katsiampoura, Gianna

2008-06-01

There is thus nothing paradoxical about the inclusion of alchemy in the ensemble of the physical sciences nor in the preoccupation with it on the part of learned men engaged in scientific study. In the context of the Medieval model, where discourse on the physical world was ambiguous, often unclear, and lacking the support of experimental verification, the transmutation of matter, which was the subject of alchemy, even if not attended by a host of occult features, was a process that was thought to have a probable basis in reality. What is interesting in this connection is the utilization of the scientific categories of the day for discussion of transmutation of matter and the attempt to avoid, in most instances in the texts that survive, of methods reminiscent of magic.

New infrastructure for studies of transmutation and fast systems concepts

NASA Astrophysics Data System (ADS)

Panza, Fabio; Firpo, Gabriele; Lomonaco, Guglielmo; Osipenko, Mikhail; Ricco, Giovanni; Ripani, Marco; Saracco, Paolo; Viberti, Carlo Maria

2017-09-01

In this work we report initial studies on a low power Accelerator-Driven System as a possible experimental facility for the measurement of relevant integral nuclear quantities. In particular, we performed Monte Carlo simulations of minor actinides and fission products irradiation and estimated the fission rate within fission chambers in the reactor core and the reflector, in order to evaluate the transmutation rates and the measurement sensitivity. We also performed a photo-peak analysis of available experimental data from a research reactor, in order to estimate the expected sensitivity of this analysis method on the irradiation of samples in the ADS considered.

Infrared absorption study of neutron-transmutation-doped germanium

NASA Technical Reports Server (NTRS)

Park, I. S.; Haller, E. E.

1988-01-01

Using high-resolution far-infrared Fourier transform absorption spectroscopy and Hall effect measurements, the evolution of the shallow acceptor and donor impurity levels in germanium during and after the neutron transmutation doping process was studied. The results show unambiguously that the gallium acceptor level concentration equals the concentration of transmutated Ge-70 atoms during the whole process indicating that neither recoil during transmutation nor gallium-defect complex formation play significant roles. The arsenic donor levels appear at full concentration only after annealing for 1 h at 450 C. It is shown that this is due to donor-radiation-defect complex formation. Again, recoil does not play a significant role.

Dual neutral particle induced transmutation in CINDER2008

NASA Astrophysics Data System (ADS)

Martin, W. J.; de Oliveira, C. R. E.; Hecht, A. A.

2014-12-01

Although nuclear transmutation methods for fission have existed for decades, the focus has been on neutron-induced reactions. Recent novel concepts have sought to use both neutrons and photons for purposes such as active interrogation of cargo to detect the smuggling of highly enriched uranium, a concept that would require modeling the transmutation caused by both incident particles. As photonuclear transmutation has yet to be modeled alongside neutron-induced transmutation in a production code, new methods need to be developed. The CINDER2008 nuclear transmutation code from Los Alamos National Laboratory is extended from neutron applications to dual neutral particle applications, allowing both neutron- and photon-induced reactions for this modeling with a focus on fission. Following standard reaction modeling, the induced fission reaction is understood as a two-part reaction, with an entrance channel to the excited compound nucleus, and an exit channel from the excited compound nucleus to the fission fragmentation. Because photofission yield data-the exit channel from the compound nucleus-are sparse, neutron fission yield data are used in this work. With a different compound nucleus and excitation, the translation to the excited compound state is modified, as appropriate. A verification and validation of these methods and data has been performed. This has shown that the translation of neutron-induced fission product yield sets, and their use in photonuclear applications, is appropriate, and that the code has been extended correctly.

A low power ADS for transmutation studies in fast systems

NASA Astrophysics Data System (ADS)

Panza, Fabio; Firpo, Gabriele; Lomonaco, Guglielmo; Osipenko, Mikhail; Ricco, Giovanni; Ripani, Marco; Saracco, Paolo; Viberti, Carlo Maria

2017-12-01

In this work, we report studies on a fast low power accelerator driven system model as a possible experimental facility, focusing on its capabilities in terms of measurement of relevant integral nuclear quantities. In particular, we performed Monte Carlo simulations of minor actinides and fission products irradiation and estimated the fission rate within fission chambers in the reactor core and the reflector, in order to evaluate the transmutation rates and the measurement sensitivity. We also performed a photo-peak analysis of available experimental data from a research reactor, in order to estimate the expected sensitivity of this analysis method on the irradiation of samples in the ADS considered.

The Fast-spectrum Transmutation Experimental Facility FASTEF: Main design achievements (part 2: Reactor building design and plant layout) within the FP7-CDT collaborative project of the European Commission

DOE Office of Scientific and Technical Information (OSTI.GOV)

De Bruyn, D.; Engelen, J.; Ortega, A.

MYRRHA (Multi-purpose hybrid Research Reactor for High-tech Applications) is the flexible experimental accelerator-driven system (ADS) in development at SCK-CEN in replacement of its material testing reactor BR2. SCK-CEN in association with 17 European partners from industry, research centres and academia, responded to the FP7 (Seventh Framework Programme) call from the European Commission to establish a Central Design Team (CDT) for the design of a Fast Spectrum Transmutation Experimental Facility (FASTEF) able to demonstrate efficient transmutation and associated technology through a system working in subcritical and/or critical mode. The project has started on April 01, 2009 for a period of threemore » years. In this paper, we present the latest concept of the reactor building and the plant layout. The FASTEF facility has evolved quite a lot since the intermediate reporting done at the ICAPP'10 and ICAPP'11 conferences 1,2. Many iterations have been performed to take into account the safety requirements. The present configuration enables an easy operation and maintenance of the facility, including the possibility to change large components of the reactor. In a companion paper 3, we present the latest configuration of the reactor core and primary system. (authors)« less

FCRD Advanced Reactor (Transmutation) Fuels Handbook

DOE Office of Scientific and Technical Information (OSTI.GOV)

Janney, Dawn Elizabeth; Papesch, Cynthia Ann

2016-09-01

Transmutation of minor actinides such as Np, Am, and Cm in spent nuclear fuel is of international interest because of its potential for reducing the long-term health and safety hazards caused by the radioactivity of the spent fuel. One important approach to transmutation (currently being pursued by the DOE Fuel Cycle Research & Development Advanced Fuels Campaign) involves incorporating the minor actinides into U-Pu-Zr alloys, which can be used as fuel in fast reactors. U-Pu-Zr alloys are well suited for electrolytic refining, which leads to incorporation rare-earth fission products such as La, Ce, Pr, and Nd. It is, therefore, importantmore » to understand not only the properties of U-Pu-Zr alloys but also those of U-Pu-Zr alloys with concentrations of minor actinides (Np, Am) and rare-earth elements (La, Ce, Pr, and Nd) similar to those in reprocessed fuel. In addition to requiring extensive safety precautions, alloys containing U, Pu, and minor actinides (Np and Am) are difficult to study for numerous reasons, including their complex phase transformations, characteristically sluggish phasetransformation kinetics, tendency to produce experimental results that vary depending on the histories of individual samples, rapid oxidation, and sensitivity to contaminants such as oxygen in concentrations below a hundred parts per million. Although less toxic, rare-earth elements such as La, Ce, Pr, and Nd are also difficult to study for similar reasons. Many of the experimental measurements were made before 1980, and the level of documentation for experimental methods and results varies widely. It is, therefore, not surprising that little is known with certainty about U-Pu-Zr alloys, particularly those that also contain minor actinides and rare-earth elements. General acceptance of results commonly indicates that there is only a single measurement for a particular property. This handbook summarizes currently available information about U, Pu, Zr, Np, Am, La, Ce, Pr, and

Vortex transmutation.

PubMed

Ferrando, Albert; Zacarés, Mario; García-March, Miguel-Angel; Monsoriu, Juan A; de Córdoba, Pedro Fernández

2005-09-16

Using group theory arguments and numerical simulations, we demonstrate the possibility of changing the vorticity or topological charge of an individual vortex by means of the action of a system possessing a discrete rotational symmetry of finite order. We establish on theoretical grounds a "transmutation pass" determining the conditions for this phenomenon to occur and numerically analyze it in the context of two-dimensional optical lattices. An analogous approach is applicable to the problems of Bose-Einstein condensates in periodic potentials.

The Dubna-Mainz-Taipei Dynamical Model for πN Scattering and π Electromagnetic Production

NASA Astrophysics Data System (ADS)

Yang, Shin Nan

Some of the featured results of the Dubna-Mainz-Taipei (DMT) dynamical model for πN scattering and π0 electromagnetic production are summarized. These include results for threshold π0 production, deformation of Δ(1232),and the extracted properties of higher resonances below 2 GeV. The excellent agreement of DMT model's predictions with threshold π0 production data, including the recent precision measurements from MAMI establishes results of DMT model as a benchmark for experimentalists and theorists in dealing with threshold pion production.

Industrial research for transmutation scenarios

NASA Astrophysics Data System (ADS)

Camarcat, Noel; Garzenne, Claude; Le Mer, Joël; Leroyer, Hadrien; Desroches, Estelle; Delbecq, Jean-Michel

2011-04-01

This article presents the results of research scenarios for americium transmutation in a 22nd century French nuclear fleet, using sodium fast breeder reactors. We benchmark the americium transmutation benefits and drawbacks with a reference case consisting of a hypothetical 60 GWe fleet of pure plutonium breeders. The fluxes in the various parts of the cycle (reactors, fabrication plants, reprocessing plants and underground disposals) are calculated using EDF's suite of codes, comparable in capabilities to those of other research facilities. We study underground thermal heat load reduction due to americium partitioning and repository area minimization. We endeavor to estimate the increased technical complexity of surface facilities to handle the americium fluxes in special fuel fabrication plants, americium fast burners, special reprocessing shops, handling equipments and transport casks between those facilities.

Automation of experiments at Dubna Gas-Filled Recoil Separator

NASA Astrophysics Data System (ADS)

Tsyganov, Yu. S.

2016-01-01

Approaches to solving the problems of automation of basic processes in long-term experiments in heavy ion beams of the Dubna Gas-Filled Recoil Separator (DGFRS) facility are considered. Approaches in the field of spectrometry, both of rare α decays of superheavy nuclei and those for constructing monitoring systems to provide accident-free experiment running with highly radioactive targets and recording basic parameters of experiment, are described. The specific features of Double Side Silicon Strip Detectors (DSSSDs) are considered, special attention is paid to the role of boundary effects of neighboring p-n transitions in the "active correlations" method. An example of an off-beam experiment attempting to observe Zeno effect is briefly considered. Basic examples for nuclear reactions of complete fusion at 48Ca ion beams of U-400 cyclotron (LNR, JINR) are given. A scenario of development of the "active correlations" method for the case of very high intensity beams of heavy ions at promising accelerators of LNR, JINR, is presented.

Analysis of the Gas Core Actinide Transmutation Reactor (GCATR)

NASA Technical Reports Server (NTRS)

Clement, J. D.; Rust, J. H.

1977-01-01

Design power plant studies were carried out for two applications of the plasma core reactor: (1) As a breeder reactor, (2) As a reactor able to transmute actinides effectively. In addition to the above applications the reactor produced electrical power with a high efficiency. A reactor subsystem was designed for each of the two applications. For the breeder reactor, neutronics calculations were carried out for a U-233 plasma core with a molten salt breeding blanket. A reactor was designed with a low critical mass (less than a few hundred kilograms U-233) and a breeding ratio of 1.01. The plasma core actinide transmutation reactor was designed to transmute the nuclear waste from conventional LWR's. The spent fuel is reprocessed during which 100% of Np, Am, Cm, and higher actinides are separated from the other components. These actinides are then manufactured as oxides into zirconium clad fuel rods and charged as fuel assemblies in the reflector region of the plasma core actinide transmutation reactor. In the equilibrium cycle, about 7% of the actinides are directly fissioned away, while about 31% are removed by reprocessing.

Feasibility study of nuclear transmutation by negative muon capture reaction using the PHITS code

NASA Astrophysics Data System (ADS)

Abe, Shin-ichiro; Sato, Tatsuhiko

2016-06-01

Feasibility of nuclear transmutation of fission products in high-level radioactive waste by negative muon capture reaction is investigated using the Particle and Heave Ion Transport code System (PHITS). It is found that about 80 % of stopped negative muons contribute to transmute target nuclide into stable or short-lived nuclide in the case of 135Cs, which is one of the most important nuclide in the transmutation. The simulation result also indicates that the position of transmutation is controllable by changing the energy of incident negative muon. Based on our simulation, it takes approximately 8.5 × 108years to transmute 500 g of 135Cs by negative muon beam with the highest intensity currently available.

Role of (n,2n) reactions in transmutation of long-lived fission products

DOE Office of Scientific and Technical Information (OSTI.GOV)

Apse, V. A.; Kulikov, G. G., E-mail: ggkulikov@mephi.ru; Kulikov, E. G.

2016-12-15

The conditions under which (n,γ) and (n,2n) reactions can help or hinder each other in neutron transmutation of long-lived fission products (LLFPs) are considered. Isotopic and elemental transmutation for the main long-lived fission products, {sup 79}Se, {sup 93}Zr, {sup 99}Tc, {sup 107}Pd, {sup 126}Sn, {sup 129}I, and {sup 135}Cs, are considered. The effect of (n,2n) reactions on the equilibrium amount of nuclei of the transmuted isotope and the neutron consumption required for the isotope processing is estimated. The aim of the study is to estimate the influence of (n,2n) reactions on efficiency of neutron LLFP transmutation. The code TIME26 andmore » the libraries of evaluated nuclear data ABBN-93, JEF-PC, and JANIS system are applied. The following results are obtained: (1) The effect of (n,2n) reactions on the minimum number of neutrons required for transmutation and the equilibrium amount of LLFP nuclei is estimated. (2) It is demonstrated that, for three LLFP isotopes ({sup 126}Sn, {sup 129}I, and {sup 135}Cs), (n,γ) and (n,2n) reactions are partners facilitating neutron transmutation. The strongest effect of (n,2n) reaction is found for {sup 126}Sn transmutation (reduction of the neutron consumption by 49% and the equilibrium amount of nuclei by 19%).« less

Application of gaseous core reactors for transmutation of nuclear waste

NASA Technical Reports Server (NTRS)

Schnitzler, B. G.; Paternoster, R. R.; Schneider, R. T.

1976-01-01

An acceptable management scheme for high-level radioactive waste is vital to the nuclear industry. The hazard potential of the trans-uranic actinides and of key fission products is high due to their nuclear activity and/or chemical toxicity. Of particular concern are the very long-lived nuclides whose hazard potential remains high for hundreds of thousands of years. Neutron induced transmutation offers a promising technique for the treatment of problem wastes. Transmutation is unique as a waste management scheme in that it offers the potential for "destruction" of the hazardous nuclides by conversion to non-hazardous or more manageable nuclides. The transmutation potential of a thermal spectrum uranium hexafluoride fueled cavity reactor was examined. Initial studies focused on a heavy water moderated cavity reactor fueled with 5% enriched U-235-F6 and operating with an average thermal flux of 6 times 10 to the 14th power neutrons/sq cm-sec. The isotopes considered for transmutation were I-129, Am-241, Am-242m, Am-243, Cm-243, Cm-244, Cm-245, and Cm-246.

JAERI R & D on accelerator-based transmutation under OMEGA program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takizuka, T.; Nishida, T.; Mizumoto, M.

1995-10-01

The overview of the Japanese long-term research and development program on nuclide partitioning and transmutation, called {open_quotes}OMEGA,{close_quotes} is presented. Under this national program, major R&D activities are being carried out at JAERI, PNC, and CRIEPI. Accelerator-based transmutation study at JAERI is focused on a dedicated transmutor with a subcritical actinide-fueled subcritical core coupled with a spallation target driven by a high intensity proton accelerator. Two types of system concept, solid system and molten-salt system, are discussed. The solid system consists of sodium-cooled tungsten target and metallic actinide fuel. The molten-salt system is fueled with molten actinide chloride that acts alsomore » as a target material. The proposed plant transmutes about 250 kg of minor actinide per year, and generates enough electricity to power its own accelerator. JAERI is proposing the development of an intense proton linear accelerator ETA with 1.5 GeV-10 mA beam for engineering tests of accelerator-based transmutation. Recent achievements in the accelerator development are described.« less

Transmutation of planar media singularities in a conformal cloak.

PubMed

Liu, Yichao; Mukhtar, Musawwadah; Ma, Yungui; Ong, C K

2013-11-01

Invisibility cloaking based on optical transformation involves materials singularity at the branch cut points. Many interesting optical devices, such as the Eaton lens, also require planar media index singularities in their implementation. We show a method to transmute two singularities simultaneously into harmless topological defects formed by anisotropic permittivity and permeability tensors. Numerical simulation is performed to verify the functionality of the transmuted conformal cloak consisting of two kissing Maxwell fish eyes.

Technical and economic assessment of different options for minor actinide transmutation: the French case

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chabert, C.; Coquelet-Pascal, C.; Saturnin, A.

Studies have been performed to assess the industrial perspectives of partitioning and transmutation of long-lived elements. These studies were carried out in tight connection with GEN-IV systems development. The results include the technical and economic evaluation of fuel cycle scenarios along with different options for optimizing the processes between the minor actinide transmutation in fast neutron reactors, their interim storage and geological disposal of ultimate waste. The results are analysed through several criteria (impacts on waste, on waste repository, on fuel cycle plants, on radiological exposure of workers, on costs and on industrial risks). These scenario evaluations take place inmore » the French context which considers the deployment of the first Sodium-cooled Fast Reactor (SFR) in 2040. 3 management options of minor actinides have been studied: no transmutation, transmutation in SFR and transmutation in an accelerator-driven system (ADS). Concerning economics the study shows that the cost overrun related to the transmutation process could vary between 5 to 9% in SFR and 26 % in the case of ADS.« less

Transmutation: The Roots of the Dream.

ERIC Educational Resources Information Center

Karpenko, Vladimir

1995-01-01

Examines the history of alchemical attempts at transmutation and classifies them by differing approaches and techniques. Traces the development of alchemy in Asia, Europe, and the Middle East, and compares alchemy with craftsmanship. (18 references) (DDR)

Algorithm for Search and Recovery of the Vertex of Decay in the Hypernuclear Experiment NIS-GIBS at Dubna Nuclotron

DOE Office of Scientific and Technical Information (OSTI.GOV)

Korotkova, Anna M.; Lukstins, Juris

2010-01-05

Search of the decay vertex is an important part of the hypernuclear experiment, carried out of the Dubna nuclotron accelerator. The decay vertex is reconstructed from data from two sets of proportional chambers. The distribution of the vertex of decay of the hypernucleus allows to measure the lifetime of the hypernuclei. Algorithm for searches and automatically calculates the decay vertex has been written.

Neutron transmutation doped Ge bolometers

NASA Technical Reports Server (NTRS)

Haller, E. E.; Kreysa, E.; Palaio, N. P.; Richards, P. L.; Rodder, M.

1983-01-01

Some conclusions reached are as follow. Neutron Transmutation Doping (NTD) of high quality Ge single crystals provides perfect control of doping concentration and uniformity. The resistivity can be tailored to any given bolometer operating temperature down to 0.1 K and probably lower. The excellent uniformity is advantaged for detector array development.

Statistical transmutation in doped quantum dimer models.

PubMed

Lamas, C A; Ralko, A; Cabra, D C; Poilblanc, D; Pujol, P

2012-07-06

We prove a "statistical transmutation" symmetry of doped quantum dimer models on the square, triangular, and kagome lattices: the energy spectrum is invariant under a simultaneous change of statistics (i.e., bosonic into fermionic or vice versa) of the holes and of the signs of all the dimer resonance loops. This exact transformation enables us to define the duality equivalence between doped quantum dimer Hamiltonians and provides the analytic framework to analyze dynamical statistical transmutations. We investigate numerically the doping of the triangular quantum dimer model with special focus on the topological Z(2) dimer liquid. Doping leads to four (instead of two for the square lattice) inequivalent families of Hamiltonians. Competition between phase separation, superfluidity, supersolidity, and fermionic phases is investigated in the four families.

FIRST-PRINCIPLES CALCULATIONS OF INTRINSIC DEFECTS AND Mg TRANSMUTANTS IN 3C-SiC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Shenyang Y.; Setyawan, Wahyu; Van Ginhoven, Renee M.

2013-09-25

Silicon carbide (SiC) possesses many desirable attributes for applications in high-temperature and neutron radiation environments. These attributes include excellent dimensional and thermodynamic stability, low activation, high strength, and high thermal conductivity. Therefore, SiC based materials draw broad attention as structural materials for the first wall (FW) and blanket in fusion power plants. Under the severe high-energy neutron environment of D-T fusion systems, SiC suffers significant transmutation resulting in both gaseous and metallic transmutants. Recent calculations by Sawan, et al. [2] predict that at a fast neutron dose of ~100 dpa, there will be about 0.5 at% Mg generated in SiCmore » through nuclear transmutation. Other transmutation products, including 0.15 at% Al, 0.2 at% Be and 2.2 at% He, also emerge. Formation and migration energies of point defects in 3C-SiC have been widely investigated using density functional theory (DFT). However, the properties of defects associated with transmutants are currently not well understood. Fundamental understanding of where the transmutation products go and how they affect microstructure evolution of SiC composites will help to predict property evolution and performance of SiC-based materials in fusion reactors.« less

An optimization methodology for heterogeneous minor actinides transmutation

NASA Astrophysics Data System (ADS)

Kooyman, Timothée; Buiron, Laurent; Rimpault, Gérald

2018-04-01

In the case of a closed fuel cycle, minor actinides transmutation can lead to a strong reduction in spent fuel radiotoxicity and decay heat. In the heterogeneous approach, minor actinides are loaded in dedicated targets located at the core periphery so that long-lived minor actinides undergo fission and are turned in shorter-lived fission products. However, such targets require a specific design process due to high helium production in the fuel, high flux gradient at the core periphery and low power production. Additionally, the targets are generally manufactured with a high content in minor actinides in order to compensate for the low flux level at the core periphery. This leads to negative impacts on the fuel cycle in terms of neutron source and decay heat of the irradiated targets, which penalize their handling and reprocessing. In this paper, a simplified methodology for the design of targets is coupled with a method for the optimization of transmutation which takes into account both transmutation performances and fuel cycle impacts. The uncertainties and performances of this methodology are evaluated and shown to be sufficient to carry out scoping studies. An illustration is then made by considering the use of moderating material in the targets, which has a positive impact on the minor actinides consumption but a negative impact both on fuel cycle constraints (higher decay heat and neutron) and on assembly design (higher helium production and lower fuel volume fraction). It is shown that the use of moderating material is an optimal solution of the transmutation problem with regards to consumption and fuel cycle impacts, even when taking geometrical design considerations into account.

Energy Production and Transmutation of Nuclear Waste by Accelerator Driven Systems

NASA Astrophysics Data System (ADS)

Zhivkov, P. K.

2018-05-01

There is a significant amount of highly radiotoxic long-life nuclear waste (NW) produced by NPP (Nuclear Power Plants). Transmutation is a process which transforms NW into less radiotoxic nuclides with a shorter period of half-life by spallation neutrons or radiative capture of neutrons produced by ADS (Accelerator Driven System). In the processes of transmutation new radioactive nuclides are produced. ADS is big energy consumer equipment. It is a method for production of a high-flux and high-energy neutron field. All these processes occur in ADS simultaneously. ADS is able to transmute actinides and produce energy simultaneously. The article considers the energy production problems in ADS. Several ideas are developed regarding the solution of the global energy supply.

Spatial heterogeneity of tungsten transmutation in a fusion device

NASA Astrophysics Data System (ADS)

Gilbert, M. R.; Sublet, J.-Ch.; Dudarev, S. L.

2017-04-01

Accurately quantifying the transmutation rate of tungsten (W) under neutron irradiation is a necessary requirement in the assessment of its performance as an armour material in a fusion power plant. The usual approach of calculating average responses, assuming large, homogenised material volumes, is insufficient to capture the full complexity of the transmutation picture in the context of a realistic fusion power plant design, particularly for rhenium (Re) production from W. Combined neutron transport and inventory simulations for representative spatially heterogeneous high-resolution models of a fusion power plant show that the production rate of Re is strongly influenced by the surrounding local spatial environment. Localised variation in neutron moderation (slowing down) due to structural steel and coolant, particularly water, can dramatically increase Re production because of the huge cross sections of giant resolved resonances in the neutron-capture reaction of 186W at low neutron energies. Calculations using cross section data corrected for temperature (Doppler) effects suggest that temperature may have a relatively lesser influence on transmutation rates.

MA transmutation performance in the optimized MYRRHA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Malambu, E.; Van den Eynde, G.; Fernandez, R.

MYRRHA (multi-purpose hybrid research reactor for high-tech applications) is a multipurpose research facility currently being developed at SCK-CEN. It will be able to work in both critical and subcritical modes and, cooled by lead-bismuth eutectic. In this paper the minor actinides (MA) transmutation capabilities of MYRRHA are investigated. (Pu + Am, U) MOX fuel and (Np + Am + Cm, Pu) Inert Matrix Fuel test samples have been loaded in the central channel of the MYRRHA critical core and have been irradiated during five cycles, each one consisting of 90 days of operation at 100 MWth and 30 days ofmore » shutdown. The reactivity worth of the test fuel assembly was about 1.1 dollar. A wide range of burn-up level has been achieved, extending from 42 to 110 MWd/kg HM, the samples with lower MA-to-Pu ratios reaching the highest burn-up. This study has highlighted the importance of the initial MA content, expressed in terms of MA/Pu ratio, on the transmutation rate of MA elements. For (Pu + Am, U) MOX fuel samples, a net build-up of MA is observed when the initial content of MA is very low (here, 1.77 wt% MA/Pu) while a net decrease in MA is observed in the sample with an initial content of 5 wt%. This suggests the existence of some 'equilibrium' initial MA content value beyond which a net transmutation is achievable.« less

Method to Reduce Long-lived Fission Products by Nuclear Transmutations with Fast Spectrum Reactors.

PubMed

Chiba, Satoshi; Wakabayashi, Toshio; Tachi, Yoshiaki; Takaki, Naoyuki; Terashima, Atsunori; Okumura, Shin; Yoshida, Tadashi

2017-10-24

Transmutation of long-lived fission products (LLFPs: 79 Se, 93 Zr, 99 Tc, 107 Pd, 129 I, and 135 Cs) into short-lived or non-radioactive nuclides by fast neutron spectrum reactors without isotope separation has been proposed as a solution to the problem of radioactive wastes disposal. Despite investigation of many methods, such transmutation remains technologically difficult. To establish an effective and efficient transmutation system, we propose a novel neutron moderator material, yttrium deuteride (YD 2 ), to soften the neutron spectrum leaking from the reactor core. Neutron energy spectra and effective half-lives of LLFPs, transmutation rates, and support ratios were evaluated with the continuous-energy Monte Carlo code MVP-II/MVP-BURN and the JENDL-4.0 cross section library. With the YD 2 moderator in the radial blanket and shield regions, effective half-lives drastically decreased from 106 to 102 years and the support ratios reached 1.0 for all six LLFPs. This successful development and implementation of a transmutation system for LLFPs without isotope separation contributes to a the ability of fast spectrum reactors to reduce radioactive waste by consuming their own LLFPs.

Promises and Challenges of Thorium Implementation for Transuranic Transmutation - 13550

DOE Office of Scientific and Technical Information (OSTI.GOV)

Franceschini, F.; Lahoda, E.; Wenner, M.

2013-07-01

This paper focuses on the challenges of implementing a thorium fuel cycle for recycle and transmutation of long-lived actinide components from used nuclear fuel. A multi-stage reactor system is proposed; the first stage consists of current UO{sub 2} once-through LWRs supplying transuranic isotopes that are continuously recycled and burned in second stage reactors in either a uranium (U) or thorium (Th) carrier. The second stage reactors considered for the analysis are Reduced Moderation Pressurized Water Reactors (RMPWRs), reconfigured from current PWR core designs, and Fast Reactors (FRs) with a burner core design. While both RMPWRs and FRs can in principlemore » be employed, each reactor and associated technology has pros and cons. FRs have unmatched flexibility and transmutation efficiency. RMPWRs have higher fuel manufacturing and reprocessing requirements, but may represent a cheaper solution and the opportunity for a shorter time to licensing and deployment. All options require substantial developments in manufacturing, due to the high radiation field, and reprocessing, due to the very high actinide recovery ratio to elicit the claimed radiotoxicity reduction. Th reduces the number of transmutation reactors, and is required to enable a viable RMPWR design, but presents additional challenges on manufacturing and reprocessing. The tradeoff between the various options does not make the choice obvious. Moreover, without an overarching supporting policy in place, the costly and challenging technologies required inherently discourage industrialization of any transmutation scheme, regardless of the adoption of U or Th. (authors)« less

Optimisation of composite metallic fuel for minor actinide transmutation in an accelerator-driven system

NASA Astrophysics Data System (ADS)

Uyttenhove, W.; Sobolev, V.; Maschek, W.

2011-09-01

A potential option for neutralization of minor actinides (MA) accumulated in spent nuclear fuel of light water reactors (LWRs) is their transmutation in dedicated accelerator-driven systems (ADS). A promising fuel candidate dedicated to MA transmutation is a CERMET composite with Mo metal matrix and (Pu, Np, Am, Cm)O 2-x fuel particles. Results of optimisation studies of the CERMET fuel targeting to increasing the MA transmutation efficiency of the EFIT (European Facility for Industrial Transmutation) core are presented. In the adopted strategy of MA burning the plutonium (Pu) balance of the core is minimized, allowing a reduction in the reactivity swing and the peak power form-factor deviation and an extension of the cycle duration. The MA/Pu ratio is used as a variable for the fuel optimisation studies. The efficiency of MA transmutation is close to the foreseen theoretical value of 42 kg TW -1 h -1 when level of Pu in the actinide mixture is about 40 wt.%. The obtained results are compared with the reference case of the EFIT core loaded with the composite CERCER fuel, where fuel particles are incorporated in a ceramic magnesia matrix. The results of this study offer additional information for the EFIT fuel selection.

Electric Spark Discharges in Water. Low-energy Nuclear Transmutations and Light Leptonic Magnetic Monopoles in an Extended Standard Model

NASA Astrophysics Data System (ADS)

Stumpf, Harald

2017-08-01

Light leptonic magnetic monopoles were predicted by Lochak [G. Lochak, Intern. J. Theor. Phys. 24, 1019 (1985).]. Experimental indications based on nuclear transmutations were announced by Urutskoiev et al. [L. I. Urutskoiev, V. I. Liksonov, V. G. Tsinoev, Ann. Fond. L. de Broglie 27, Nr.4, 791 (2002).] and Urutskoev [L. J. Urutskoev, Ann. Fond. L. de Broglie 29, 1149 (2004).]. A theoretical interpretation of these transmutations is proposed under the assumption that light leptonic magnetic monopoles are created during spark discharges in water. The latter should be excited neutrinos according to Lochak. This hypothesis enforces the introduction of an extended Standard Model described in previous papers. The most important results of this study are (i) that multiple proton captures are responsible for the variety of transmutations and that leptonic magnetic monopoles are involved in these processes (ii) that electromagnetic duality can be established for bound states of leptonic monopoles although massive monopoles are in general unstable (iii) that criteria for the emission of leptonic magnetic monopoles and for their catalytic effect on weak decays are set up and elaborated. The study can be considered as a contribution to the efforts of Urutskoiev and Lochak to understand the reasons for accidents in power plants.

Transmuted of Rayleigh Distribution with Estimation and Application on Noise Signal

NASA Astrophysics Data System (ADS)

Ahmed, Suhad; Qasim, Zainab

2018-05-01

This paper deals with transforming one parameter Rayleigh distribution, into transmuted probability distribution through introducing a new parameter (λ), since this studied distribution is necessary in representing signal data distribution and failure data model the value of this transmuted parameter |λ| ≤ 1, is also estimated as well as the original parameter (⊖) by methods of moments and maximum likelihood using different sample size (n=25, 50, 75, 100) and comparing the results of estimation by statistical measure (mean square error, MSE).

Heterogeneous sodium fast reactor designed for transmuting minor actinide waste isotopes into plutonium fuel

NASA Astrophysics Data System (ADS)

Bays, Samuel Eugene

2008-10-01

In the past several years there has been a renewed interest in sodium fast reactor (SFR) technology for the purpose of destroying transuranic waste (TRU) produced by light water reactors (LWR). The utility of SFRs as waste burners is due to the fact that higher neutron energies allow all of the actinides, including the minor actinides (MA), to contribute to fission. It is well understood that many of the design issues of LWR spent nuclear fuel (SNF) disposal in a geologic repository are linked to MAs. Because the probability of fission for essentially all the "non-fissile" MAs is nearly zero at low neutron energies, these isotopes act as a neutron capture sink in most thermal reactor systems. Furthermore, because most of the isotopes produced by these capture reactions are also non-fissile, they too are neutron sinks in most thermal reactor systems. Conversely, with high neutron energies, the MAs can produce neutrons by fast fission. Additionally, capture reactions transmute the MAs into mostly plutonium isotopes, which can fission more readily at any energy. The transmutation of non-fissile into fissile atoms is the premise of the plutonium breeder reactor. In a breeder reactor, not only does the non-fissile "fertile" U-238 atom contribute fast fission neutrons, but also transmutes into fissile Pu-239. The fissile value of the plutonium produced by MA transmutation can only be realized in fast neutron spectra. This is due to the fact that the predominate isotope produced by MA transmutation, Pu-238, is itself not fissile. However, the Pu-238 fission cross section is significantly larger than the original transmutation parent, predominately: Np-237 and Am-241, in the fast energy range. Also, Pu-238's fission cross section and fission-to-capture ratio is almost as high as that of fissile Pu-239 in the fast neutron spectrum. It is also important to note that a neutron absorption in Pu-238, that does not cause fission, will instead produce fissile Pu-239. Given this

Gas core reactors for actinide transmutation and breeder applications

NASA Technical Reports Server (NTRS)

Clement, J. D.; Rust, J. H.

1978-01-01

This work consists of design power plant studies for four types of reactor systems: uranium plasma core breeder, uranium plasma core actinide transmuter, UF6 breeder and UF6 actinide transmuter. The plasma core systems can be coupled to MHD generators to obtain high efficiency electrical power generation. A 1074 MWt UF6 breeder reactor was designed with a breeding ratio of 1.002 to guard against diversion of fuel. Using molten salt technology and a superheated steam cycle, an efficiency of 39.2% was obtained for the plant and the U233 inventory in the core and heat exchangers was limited to 105 Kg. It was found that the UF6 reactor can produce high fluxes (10 to the 14th power n/sq cm-sec) necessary for efficient burnup of actinide. However, the buildup of fissile isotopes posed severe heat transfer problems. Therefore, the flux in the actinide region must be decreased with time. Consequently, only beginning-of-life conditions were considered for the power plant design. A 577 MWt UF6 actinide transmutation reactor power plant was designed to operate with 39.3% efficiency and 102 Kg of U233 in the core and heat exchanger for beginning-of-life conditions.

Transmutation of Nuclear Waste and the future MYRRHA Demonstrator

NASA Astrophysics Data System (ADS)

Mueller, Alex C.

2013-03-01

While a considerable and world-wide growth of the nuclear share in the global energy mix is desirable for many reasons, there are also, in particular in the "old world" major objections. These are both concerns about safety, in particular in the wake of the Fukushima nuclear accident and concerns about the long-term burden that is constituted by the radiotoxic waste from the spent fuel. With regard to the second topic, the present contribution will outline the concept of Partitioning & Transmutation (P&T), as scientific and technological answer. Deployment of P&T may use dedicated "Transmuter" or "Burner" reactors, using a fast neutron spectrum. For the transmutation of waste with a large content (up to 50%) of (very long-lived) Minor Actinides, a sub-critical reactor, using an external neutron source is a most attractive solution. It is constituted by coupling a proton accelerator, a spallation target and a subcritical core. This promising new technology is named ADS, for accelerator-driven system. The present paper aims at a short introduction into the field that has been characterized by a high collaborative activity during the last decade in Europe, in order to focus, in its later part, on the MYRRHA project as the European ADS technology demonstrator.

Transmutation prospect of long-lived nuclear waste induced by high-charge electron beam from laser plasma accelerator

NASA Astrophysics Data System (ADS)

Wang, X. L.; Xu, Z. Y.; Luo, W.; Lu, H. Y.; Zhu, Z. C.; Yan, X. Q.

2017-09-01

Photo-transmutation of long-lived nuclear waste induced by a high-charge relativistic electron beam (e-beam) from a laser plasma accelerator is demonstrated. A collimated relativistic e-beam with a high charge of approximately 100 nC is produced from high-intensity laser interaction with near-critical-density (NCD) plasma. Such e-beam impinges on a high-Z convertor and then radiates energetic bremsstrahlung photons with flux approaching 1011 per laser shot. Taking a long-lived radionuclide 126Sn as an example, the resulting transmutation reaction yield is the order of 109 per laser shot, which is two orders of magnitude higher than obtained from previous studies. It is found that at lower densities, a tightly focused laser irradiating relatively longer NCD plasmas can effectively enhance the transmutation efficiency. Furthermore, the photo-transmutation is generalized by considering mixed-nuclide waste samples, which suggests that the laser-accelerated high-charge e-beam could be an efficient tool to transmute long-lived nuclear waste.

Average fast neutron flux in three energy ranges in the Quinta assembly irradiated by two types of beams

NASA Astrophysics Data System (ADS)

Strugalska-Gola, Elzbieta; Bielewicz, Marcin; Kilim, Stanislaw; Szuta, Marcin; Tyutyunnikov, Sergey

2017-03-01

This work was performed within the international project "Energy plus Transmutation of Radioactive Wastes" (E&T - RAW) for investigations of energy production and transmutation of radioactive waste of the nuclear power industry. 89Y (Yttrium 89) samples were located in the Quinta assembly in order to measure an average high neutron flux density in three different energy ranges using deuteron and proton beams from Dubna accelerators. Our analysis showed that the neutron density flux for the neutron energy range 20.8 - 32.7 MeV is higher than for the neutron energy range 11.5 - 20.8 MeV both for protons with an energy of 0.66 GeV and deuterons with an energy of 2 GeV, while for deuteron beams of 4 and 6 GeV we did not observe this.

Object kinetic Monte Carlo model for neutron and ion irradiation in tungsten: Impact of transmutation and carbon impurities

NASA Astrophysics Data System (ADS)

Castin, N.; Bonny, G.; Bakaev, A.; Ortiz, C. J.; Sand, A. E.; Terentyev, D.

2018-03-01

We upgrade our object kinetic Monte Carlo (OKMC) model, aimed at describing the microstructural evolution in tungsten (W) under neutron and ion irradiation. Two main improvements are proposed based on recently published atomistic data: (a) interstitial carbon impurities, and their interaction with radiation-induced defects (point defect clusters and loops), are more accurately parameterized thanks to ab initio findings; (b) W transmutation to rhenium (Re) upon neutron irradiation, impacting the diffusivity of radiation defects, is included, also relying on recent atomistic data. These essential amendments highly improve the portability of our OKMC model, providing a description for the formation of SIA-type loops under different irradiation conditions. The model is applied to simulate neutron and ion irradiation in pure W samples, in a wide range of fluxes and temperatures. We demonstrate that it performs a realistic prediction of the population of TEM-visible voids and loops, as compared to experimental evidence. The impact of the transmutation of W to Re, and of carbon trapping, is assessed.

Automation system for neutron activation analysis at the reactor IBR-2, Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Dubna, Russia.

PubMed

Pavlov, Sergey S; Dmitriev, Andrey Yu; Frontasyeva, Marina V

The present status of development of software packages and equipment designed for automation of NAA at the reactor IBR-2 of FLNP, JINR, Dubna, RF, is described. The NAA database, construction of sample changers and software for automation of spectra measurement and calculation of concentrations are presented. Automation of QC procedures is integrated in the software developed. Details of the design are shown.

Method and apparatus for transmutation of atomic nuclei

DOEpatents

Maenchen, John Eric; Ruiz, Carlos Leon

1998-01-01

Insuring a constant supply of radioisotopes is of great importance to medicine and industry. This invention addresses this problem, and helps to solve it by introducing a new apparatus for transmutation of isotopes which enables swift and flexible production on demand.

Method and apparatus for transmutation of atomic nuclei

DOEpatents

Maenchen, J.E.; Ruiz, C.L.

1998-12-08

Insuring a constant supply of radioisotopes is of great importance to medicine and industry. This invention addresses this problem, and helps to solve it by introducing a new apparatus for transmutation of isotopes which enables swift and flexible production on demand. 9 figs.

Method and apparatus for transmutation of atomic nuclei

DOEpatents

Maenchen, J.E.; Ruiz, C.L.

1998-06-09

Insuring a constant supply of radioisotopes is of great importance to medicine and industry. This invention addresses this problem, and helps to solve it by introducing a new apparatus for transmutation of isotopes which enables swift and flexible production on demand. 9 figs.

Prospects for the study of the properties of dense nuclear matter at the NICA heavy-ion complex at JINR (Dubna)

NASA Astrophysics Data System (ADS)

Kolesnikov, V. I.

2017-06-01

The NICA (Nuclotron-based Ion Collider fAcility) project is aimed in the construction at JINR (Dubna) a modern accelerator complex equipped with three detectors: the MultiPurpose Detector (MPD) and the Spin Physics Detector (SPD) at the NICA collider, as well as a fixed target experiment BM&N which will be use extracted beams from the Nuclotron accelerator. In this report, an overview of the main physics objectives of the NICA heavy-ion program will be given and the recent progress in the NICA construction (both accelerator complex and detectors) will be described.

IAEA activities in the area of partitioning and transmutation

NASA Astrophysics Data System (ADS)

Stanculescu, Alexander

2006-06-01

Four major challenges are facing the long-term development of nuclear energy: improvement of the economic competitiveness, meeting increasingly stringent safety requirements, adhering to the criteria of sustainable development, and public acceptance. Meeting the sustainability criteria is the driving force behind the topic of this paper. In this context, sustainability has two aspects: natural resources and waste management. IAEA's activities in the area of Partitioning and Transmutation (P&T) are mostly in response to the latter. While not involving the large quantities of gaseous products and toxic solid wastes associated with fossil fuels, radioactive waste disposal is today's dominant public acceptance issue. In fact, small waste quantities permit a rigorous confinement strategy, and mined geological disposal is the strategy followed by some countries. Nevertheless, political opposition arguing that this does not yet constitute a safe disposal technology has largely stalled these efforts. One of the primary reasons cited is the long life of many of the radioisotopes generated from fission. This concern has led to increased R&D efforts to develop a technology aimed at reducing the amount and radio-toxicity of long-lived radioactive waste through transmutation in fission reactors or sub-critical systems. In the frame of the Project on Technology Advances in Fast Reactors and Accelerator-Driven Systems (ADS), the IAEA initiated a number of activities on utilization of plutonium and transmutation of long-lived radioactive waste, ADS, and deuterium-tritium plasma-driven sub-critical systems. The paper presents past accomplishments, current status and planned activities of this IAEA project.

International programs related to the transmutation of transuranics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Newman, C.

1991-04-01

This report is an account of current programs outside the U.S. relating to the transmutation of transuranics. This work was performed under contract to EPRI. The investigation was based on literature surveys, personal discussions, and visits to European research establishments that are currently active in the area. Research in actinide (uranium plus transuranics) partitioning and transmutation (P-T) is actively promoted in Japan, where the largest program in research on P-T is currently underway; however, following years of relative inactivity, the concept is being revisited elsewhere. Additionally, a significant amount of research in reprocessing and advanced reactors has produced results withmore » interesting possibilities for P-T. Foreign research activities relevant to actinide burning is presented in two sections: foreign national programs, and international programs and working groups. In order to provide the reader with an ability to assess the motivators for or against development of P-T, background on political and institutional trends relating to nuclear waste management is also provided. 38 refs., 17 figs.« less

The DD Cold Fusion-Transmutation Connection

NASA Astrophysics Data System (ADS)

Chubb, Talbot A.

2005-12-01

LENR theory must explain dd fusion, alpha-addition transmutations, radiationless nuclear reactions, and three-body nuclear particle reactions. Reaction without radiation requires many-body D Bloch+ periodicity in both location and internal structure dependencies. Electron scattering leads to mixed quantum states. The radiationless dd fusion reaction is 2-D Bloch+ -> {}4 He Bloch2+. Overlap between {}4 He Bloch2+ and surface Cs leads to alpha absorption. In the Iwamura et al. studies active deuterium is created by scattering at diffusion barriers.

Determination of the origin of the medieval glass bracelets discovered in Dubna, Moscow region, Russia using the neutron activation analysis

NASA Astrophysics Data System (ADS)

Dmitrieva, S. O.; Frontasyeva, M. V.; Dmitriev, A. A.; Dmitriev, A. Yu.

2017-01-01

The work is dedicated to the determination of the origin of archaeological finds from medieval glass using the method of neutron activation analysis (NAA). Among such objects we can discover not only things produced in ancient Russian glassmaking workshops but also imported from Byzantium. The authors substantiate the ancient Russian origin of the medieval glass bracelets of pre-Mongol period, found on the ancient Dubna settlement. The conclusions are based on data about the glass chemical composition obtained as a result of NAA of 10 fragments of bracelets at the IBR-2 reactor (Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research).

Status of the French Research on Partitioning and Transmutation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Warin, Dominique

2007-07-01

The global energy context pleads in favor of a sustainable development of nuclear energy since the demand for energy will likely increase, whereas resources will tend to get scarcer and the prospect of global warming will drive down the consumption of fossil fuel sources. How we deal with radioactive waste is crucial in this context. The production of nuclear energy in France has been associated, since its inception, with the optimization of radioactive waste management, including the partitioning and the recycling of recoverable energetic materials. The public's concern regarding the long-term waste management made the French Government prepare and passmore » the December 1991 Law, requesting in particular, the study for fifteen years of solutions for still minimizing the quantity and the hazardousness of final waste, via partitioning and transmutation. At the end of these fifteen years of research, it is considered that partitioning techniques, which have been validated on real solutions, are at disposal. Indeed, aqueous process for separation of minor actinides from the PUREX raffinate has been brought to a point where there is reasonable assurance that industrial deployment can be successful. A key experiment has been the successful kilogram scale trials in the CEA-Marcoule Atalante facility in 2005 and this result, together with the results obtained in the frame of the successive European projects, constitutes a considerable step forward. For transmutation, CEA has conducted programs proving the feasibility of the elimination of minor actinides and fission products: fabrication of specific targets and fuels for transmutation tests in the HFR and Phenix reactors, neutronics and technology studies for critical reactors and ADS developments. Scenario studies have also allowed assessing the feasibility, at the level of cycle and fuel facilities, and the efficiency of transmutation in terms of the quantitative reduction of the final waste inventory depending of

Minor actinide transmutation in thorium and uranium matrices in heavy water moderated reactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhatti, Zaki; Hyland, B.; Edwards, G.W.R.

2013-07-01

The irradiation of Th{sup 232} breeds fewer of the problematic minor actinides (Np, Am, Cm) than the irradiation of U{sup 238}. This characteristic makes thorium an attractive potential matrix for the transmutation of these minor actinides, as these species can be transmuted without the creation of new actinides as is the case with a uranium fuel matrix. Minor actinides are the main contributors to long term decay heat and radiotoxicity of spent fuel, so reducing their concentration can greatly increase the capacity of a long term deep geological repository. Mixing minor actinides with thorium, three times more common in themore » Earth's crust than natural uranium, has the additional advantage of improving the sustainability of the fuel cycle. In this work, lattice cell calculations have been performed to determine the results of transmuting minor actinides from light water reactor spent fuel in a thorium matrix. 15-year-cooled group-extracted transuranic elements (Np, Pu, Am, Cm) from light water reactor (LWR) spent fuel were used as the fissile component in a thorium-based fuel in a heavy water moderated reactor (HWR). The minor actinide (MA) transmutation rates, spent fuel activity, decay heat and radiotoxicity, are compared with those obtained when the MA were mixed instead with natural uranium and taken to the same burnup. Each bundle contained a central pin containing a burnable neutron absorber whose initial concentration was adjusted to have the same reactivity response (in units of the delayed neutron fraction β) for coolant voiding as standard NU fuel. (authors)« less

Reflection, transmutation, annihilation, and resonance in two-component kink collisions

NASA Astrophysics Data System (ADS)

Alonso-Izquierdo, A.

2018-02-01

In this paper, the study of collisions between kinks arising in the family of MSTB models is addressed. Phenomena such as elastic kink reflection, mutual annihilation, kink-antikink transmutation and inelastic reflection are found and depend on the impact velocity.

Neutron-transmutation-doped germanium bolometers

NASA Technical Reports Server (NTRS)

Palaio, N. P.; Rodder, M.; Haller, E. E.; Kreysa, E.

1983-01-01

Six slices of ultra-pure germanium were irradiated with thermal neutron fluences between 7.5 x 10 to the 16th and 1.88 x 10 to the 18th per sq cm. After thermal annealing the resistivity was measured down to low temperatures (less than 4.2 K) and found to follow the relationship rho = rho sub 0 exp(Delta/T) in the hopping conduction regime. Also, several junction FETs were tested for noise performance at room temperature and in an insulating housing in a 4.2 K cryostat. These FETs will be used as first stage amplifiers for neutron-transmutation-doped germanium bolometers.

II. Inhibited Diffusion Driven Surface Transmutations

NASA Astrophysics Data System (ADS)

Chubb, Talbot A.

2006-02-01

This paper is the second of a set of three papers dealing with the role of coherent partitioning as a common element in Low Energy Nuclear Reactions (LENR), by which is meant cold-fusion related processes. This paper discusses the first step in a sequence of four steps that seem to be necessary to explain Iwamura 2-α-addition surface transmutations. Three concepts are examined: salt-metal interface states, sequential tunneling that transitions D+ ions from localized interstitial to Bloch form, and the general applicability of 2-dimensional vs. 3-dimensional symmetry hosting networks.

Achieving dynamic switchable filter based on a transmutable metasurface using SMA

NASA Astrophysics Data System (ADS)

Chen, Xin; Gao, Jinsong; Kang, Bonan

2017-09-01

We propose a switchable filter composed of transmutable array using shape memory alloys (SMA). It could exhibit a temperature induced morphology change spontaneously like the biological excitability, acting as a shutter that allows the incident energy to be selectively transmitted or reflected with in excess of 12dB isolation at the certain frequencies for both polarizations. Equivalent circuit models describe the operational principle qualitatively and the switching effect is underpinned by the full-wave analysis. A further physical mechanism is shown by contrasting the distributions of electric field and surface current on the surface at the same frequency for the two working modes. The experimental results consist with the theoretical simulations, indicating that the metasurface could serve as one innovative solution for manipulating the electromagnetic waves and enlighten the next generation of advanced electromagnetic materials with more freedom in the processes of design and manufacturing.

On the use of a molten salt fast reactor to apply an idealized transmutation scenario for the nuclear phase out.

PubMed

Merk, Bruno; Rohde, Ulrich; Glivici-Cotruţă, Varvara; Litskevich, Dzianis; Scholl, Susanne

2014-01-01

In the view of transmutation of transuranium (TRU) elements, molten salt fast reactors (MSFRs) offer certain advantages compared to solid fuelled reactor types like sodium cooled fast reactors (SFRs). In the first part these advantages are discussed in comparison with the SFR technology, and the research challenges are analyzed. In the second part cycle studies for the MSFR are given for different configurations--a core with U-238 fertile, a fertile free core, and a core with Th-232 as fertile material. For all cases, the transmutation potential is determined and efficient transmutation performance for the case with thorium as a fertile material as well as for the fertile free case is demonstrated and the individual advantages are discussed. The time evolution of different important isotopes is analyzed. In the third part a strategy for the optimization of the transmutation efficiency is developed. The final aim is dictated by the phase out decision of the German government, which requests to put the focus on the determination of the maximal transmutation efficiency and on an as much as possible reduced leftover of transuranium elements at the end of the reactor life. This minimal leftover is achieved by a two step procedure of a first transmuter operation phase followed by a second deep burning phase. There the U-233, which is bred in the blanket of the core consisting of thorium containing salt, is used as feed. It is demonstrated, that transmutation rates up to more than 90% can be achieved for all transuranium isotopes, while the production of undesired high elements like californium is very limited. Additionally, the adaptations needed for the simulation of a MSFR, and the used tool HELIOS 1.10 is described.

On the Use of a Molten Salt Fast Reactor to Apply an Idealized Transmutation Scenario for the Nuclear Phase Out

PubMed Central

Merk, Bruno; Rohde, Ulrich; Glivici-Cotruţă, Varvara; Litskevich, Dzianis; Scholl, Susanne

2014-01-01

In the view of transmutation of transuranium (TRU) elements, molten salt fast reactors (MSFRs) offer certain advantages compared to solid fuelled reactor types like sodium cooled fast reactors (SFRs). In the first part these advantages are discussed in comparison with the SFR technology, and the research challenges are analyzed. In the second part cycle studies for the MSFR are given for different configurations – a core with U-238 fertile, a fertile free core, and a core with Th-232 as fertile material. For all cases, the transmutation potential is determined and efficient transmutation performance for the case with thorium as a fertile material as well as for the fertile free case is demonstrated and the individual advantages are discussed. The time evolution of different important isotopes is analyzed. In the third part a strategy for the optimization of the transmutation efficiency is developed. The final aim is dictated by the phase out decision of the German government, which requests to put the focus on the determination of the maximal transmutation efficiency and on an as much as possible reduced leftover of transuranium elements at the end of the reactor life. This minimal leftover is achieved by a two step procedure of a first transmuter operation phase followed by a second deep burning phase. There the U-233, which is bred in the blanket of the core consisting of thorium containing salt, is used as feed. It is demonstrated, that transmutation rates up to more than 90% can be achieved for all transuranium isotopes, while the production of undesired high elements like californium is very limited. Additionally, the adaptations needed for the simulation of a MSFR, and the used tool HELIOS 1.10 is described. PMID:24690768

Prognosis and comparison of performances of composite CERCER and CERMET fuels dedicated to transmutation of TRU in an EFIT ADS

NASA Astrophysics Data System (ADS)

Sobolev, V.; Uyttenhove, W.; Thetford, R.; Maschek, W.

2011-07-01

The neutronic and thermomechanical performances of two composite fuel systems: CERCER with (Pu,Np,Am,Cm)O 2-x fuel particles in ceramic MgO matrix and CERMET with metallic Mo matrix, selected for transmutation of minor actinides in the European Facility for Industrial Transmutation (EFIT), were analysed aiming at their optimisation. The ALEPH burnup code system, based on MNCPX and ORIGEN codes and JEFF3.1 nuclear data library, and the modern version of the fuel rod performance code TRAFIC were used for this analysis. Because experimental data on the properties of the mixed minor-actinide oxides are scarce, and the in-reactor behaviour of the T91 steel chosen as cladding, as well as of the corrosion protective layer, is still not well-known, a set of "best estimates" provided the properties used in the code. The obtained results indicate that both fuel candidates, CERCER and CERMET, can satisfy the fuel design and safety criteria of EFIT. The residence time for both types of fuel elements can reach about 5 years with the reactivity swing within ±1000 pcm, and about 22% of the loaded MA is transmuted during this period. However, the fuel centreline temperature in the hottest CERCER fuel rod is close to the temperature above which MgO matrix becomes chemically instable. Moreover, a weak PCMI can appear in about 3 years of operation. The CERMET fuel can provide larger safety margins: the fuel temperature is more than 1000 K below the permitted level of 2380 K and the pellet-cladding gap remains open until the end of operation.

Hydrogen bond disruption in DNA base pairs from (14)C transmutation.

PubMed

Sassi, Michel; Carter, Damien J; Uberuaga, Blas P; Stanek, Christopher R; Mancera, Ricardo L; Marks, Nigel A

2014-09-04

Recent ab initio molecular dynamics simulations have shown that radioactive carbon does not normally fragment DNA bases when it decays. Motivated by this finding, density functional theory and Bader analysis have been used to quantify the effect of C → N transmutation on hydrogen bonding in DNA base pairs. We find that (14)C decay has the potential to significantly alter hydrogen bonds in a variety of ways including direct proton shuttling (thymine and cytosine), thermally activated proton shuttling (guanine), and hydrogen bond breaking (cytosine). Transmutation substantially modifies both the absolute and relative strengths of the hydrogen bonding pattern, and in two instances (adenine and cytosine), the density at the critical point indicates development of mild covalent character. Since hydrogen bonding is an important component of Watson-Crick pairing, these (14)C-induced modifications, while infrequent, may trigger errors in DNA transcription and replication.

Apparatus for nuclear transmutation and power production using an intense accelerator-generated thermal neutron flux

DOEpatents

Bowman, C.D.

1992-11-03

Apparatus for nuclear transmutation and power production using an intense accelerator-generated thermal neutron flux. High thermal neutron fluxes generated from the action of a high power proton accelerator on a spallation target allows the efficient burn-up of higher actinide nuclear waste by a two-step process. Additionally, rapid burn-up of fission product waste for nuclides having small thermal neutron cross sections, and the practicality of small material inventories while achieving significant throughput derive from employment of such high fluxes. Several nuclear technology problems are addressed including 1. nuclear energy production without a waste stream requiring storage on a geological timescale, 2. the burn-up of defense and commercial nuclear waste, and 3. the production of defense nuclear material. The apparatus includes an accelerator, a target for neutron production surrounded by a blanket region for transmutation, a turbine for electric power production, and a chemical processing facility. In all applications, the accelerator power may be generated internally from fission and the waste produced thereby is transmuted internally so that waste management might not be required beyond the human lifespan.

Apparatus for nuclear transmutation and power production using an intense accelerator-generated thermal neutron flux

DOEpatents

Bowman, Charles D.

1992-01-01

Apparatus for nuclear transmutation and power production using an intense accelerator-generated thermal neutron flux. High thermal neutron fluxes generated from the action of a high power proton accelerator on a spallation target allows the efficient burn-up of higher actinide nuclear waste by a two-step process. Additionally, rapid burn-up of fission product waste for nuclides having small thermal neutron cross sections, and the practicality of small material inventories while achieving significant throughput derive from employment of such high fluxes. Several nuclear technology problems are addressed including 1. nuclear energy production without a waste stream requiring storage on a geological timescale, 2. the burn-up of defense and commercial nuclear waste, and 3. the production of defense nuclear material. The apparatus includes an accelerator, a target for neutron production surrounded by a blanket region for transmutation, a turbine for electric power production, and a chemical processing facility. In all applications, the accelerator power may be generated internally from fission and the waste produced thereby is transmuted internally so that waste management might not be required beyond the human lifespan.

Isotopic Transmutations in Irradiated Beryllium and Their Implications on MARIA Reactor Operation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Andrzejewski, Krzysztof J.; Kulikowska, Teresa A

2004-04-15

Beryllium irradiated by neutrons with energies above 0.7 MeV undergoes (n,{alpha}) and (n,2n) reactions. The Be(n,{alpha}) reaction results in subsequent buildup of {sup 6}Li and {sup 3}He isotopes with large thermal neutron absorption cross sections causing poisoning of irradiated beryllium. The amount of the poison isotopes depends on the neutron flux level and spectrum. The high-flux MARIA reactor operated in Poland since 1975 consists of a beryllium matrix with fuel channels in cutouts of beryllium blocks. As the experimental determination of {sup 6}Li, {sup 3}H, and {sup 3}He content in the operational reactor is impossible, a systematic computational study ofmore » the effect of {sup 3}He and {sup 6}Li presence in beryllium blocks on MARIA reactor reactivity and power density distribution has been undertaken. The analysis of equations governing the transmutation has been done for neutron flux parameters typical for MARIA beryllium blocks. Study of the mutual influence of reactor operational parameters and the buildup of {sup 6}Li, {sup 3}H, and {sup 3}He in beryllium blocks has shown the necessity of a detailed spatial solution of transmutation equations in the reactor, taking into account the whole history of its operation. Therefore, fuel management calculations using the REBUS code with included chains for Be(n,{alpha})-initiated reactions have been done for the whole reactor lifetime. The calculated poisoning of beryllium blocks has been verified against the critical experiment of 1993. Finally, the current {sup 6}Li, {sup 3}H, and {sup 3}He contents, averaged for each beryllium block, have been calculated. The reactivity drop caused by this poisoning is {approx}7%.« less

Shifts in Selective Pressures on Snake Phototransduction Genes Associated with Photoreceptor Transmutation and Dim-Light Ancestry.

PubMed

Schott, Ryan K; Van Nynatten, Alexander; Card, Daren C; Castoe, Todd A; S W Chang, Belinda

2018-06-01

The visual systems of snakes are heavily modified relative to other squamates, a condition often thought to reflect their fossorial origins. Further modifications are seen in caenophidian snakes, where evolutionary transitions between rod and cone photoreceptors, termed photoreceptor transmutations, have occurred in many lineages. Little previous work, however, has focused on the molecular evolutionary underpinnings of these morphological changes. To address this, we sequenced seven snake eye transcriptomes and utilized new whole-genome and targeted capture sequencing data. We used these data to analyze gene loss and shifts in selection pressures in phototransduction genes that may be associated with snake evolutionary origins and photoreceptor transmutation. We identified the surprising loss of rhodopsin kinase (GRK1), despite a low degree of gene loss overall and a lack of relaxed selection early during snake evolution. These results provide some of the first evolutionary genomic corroboration for a dim-light ancestor that lacks strong fossorial adaptations. Our results also indicate that snakes with photoreceptor transmutation experienced significantly different selection pressures from other reptiles. Significant positive selection was found primarily in cone-specific genes, but not rod-specific genes, contrary to our expectations. These results reveal potential molecular adaptations associated with photoreceptor transmutation and also highlight unappreciated functional differences between rod- and cone-specific phototransduction proteins. This intriguing example of snake visual system evolution illustrates how the underlying molecular components of a complex system can be reshaped in response to changing selection pressures.

Preliminary neutronics design of china lead-alloy cooled demonstration reactor (CLEAR-III) for nuclear waste transmutation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Z.; Southwest Science and Technology Univ., No.350 Shushanhu Road, Shushan District, Hefei, Anhui, 230031; Chen, Y.

2012-07-01

China Lead-Alloy cooled Demonstration Reactor (CLEAR-III), which is the concept of lead-bismuth cooled accelerator driven sub-critical reactor for nuclear waste transmutation, was proposed and designed by FDS team in China. In this study, preliminary neutronics design studies have primarily focused on three important performance parameters including Transmutation Support Ratio (TSR), effective multiplication factor and blanket thermal power. The constraint parameters, such as power peaking factor and initial TRU loading, were also considered. In the specific design, uranium-free metallic dispersion fuel of (TRU-Zr)-Zr was used as one of the CLEAR-III fuel types and the ratio between MA and Pu was adjustedmore » to maximize transmutation ratio. In addition, three different fuel zones differing in the TRU fraction of the fuel were respectively employed for this subcritical reactor, and the zone sizes and TRU fractions were determined such that the linear powers of these zones were close to each other. The neutronics calculations and analyses were performed by using Multi-Functional 4D Neutronics Simulation System named VisualBUS and nuclear data library HENDL (Hybrid Evaluated Nuclear Data Library). In the preliminary design, the maximum TSRLLMA was {approx}11 and the blanket thermal power was {approx}1000 MW when the effective multiplication factor was 0.98. The results showed that good performance of transmutation could be achieved based on the subcritical reactor loaded with uranium-free fuel. (authors)« less

"Can Simple Metals Be Transmuted into Gold?" Teaching Science through a Historical Approach.

ERIC Educational Resources Information Center

Mamlok, Rachel; Ben-Zvi, Ruth; Menis, Joseph; Penick, John E.

2000-01-01

Describes the development and enactment of a new teaching unit, "Can simple metals be transmuted into gold?", through an historical approach as well as teacher preparation to teach this unit. (Contains 16 references.) (ASK)

Electrochemical reduction of CerMet fuels for transmutation using surrogate CeO2-Mo pellets

NASA Astrophysics Data System (ADS)

Claux, B.; Souček, P.; Malmbeck, R.; Rodrigues, A.; Glatz, J.-P.

2017-08-01

One of the concepts chosen for the transmutation of minor actinides in Accelerator Driven Systems or fast reactors proposes the use of fuels and targets containing minor actinides oxides embedded in an inert matrix either composed of molybdenum metal (CerMet fuel) or of ceramic magnesium oxide (CerCer fuel). Since the sufficient transmutation cannot be achieved in a single step, it requires multi-recycling of the fuel including recovery of the not transmuted minor actinides. In the present work, a pyrochemical process for treatment of Mo metal inert matrix based CerMet fuels is studied, particularly the electroreduction in molten chloride salt as a head-end step required prior the main separation process. At the initial stage, different inactive pellets simulating the fuel containing CeO2 as minor actinide surrogates were examined. The main studied parameters of the process efficiency were the porosity and composition of the pellets and the process parameters as current density and passed charge. The results indicated the feasibility of the process, gave insight into its limiting parameters and defined the parameters for the future experiment on minor actinide containing material.

Application of neutron transmutation doping method to initially p-type silicon material.

PubMed

Kim, Myong-Seop; Kang, Ki-Doo; Park, Sang-Jun

2009-01-01

The neutron transmutation doping (NTD) method was applied to the initially p-type silicon in order to extend the NTD applications at HANARO. The relationship between the irradiation neutron fluence and the final resistivity of the initially p-type silicon material was investigated. The proportional constant between the neutron fluence and the resistivity was determined to be 2.3473x10(19)nOmegacm(-1). The deviation of the final resistivity from the target for almost all the irradiation results of the initially p-type silicon ingots was at a range from -5% to 2%. In addition, the burn-up effect of the boron impurities, the residual (32)P activity and the effect of the compensation characteristics for the initially p-type silicon were studied. Conclusively, the practical methodology to perform the neutron transmutation doping of the initially p-type silicon ingot was established.

Transmutation of All German Transuranium under Nuclear Phase Out Conditions - Is This Feasible from Neutronic Point of View?

PubMed

Merk, Bruno; Litskevich, Dzianis

2015-01-01

The German government has decided for the nuclear phase out, but a decision on a strategy for the management of the highly radioactive waste is not defined yet. Partitioning and Transmutation (P&T) could be considered as a technological option for the management of highly radioactive waste, therefore a wide study has been conducted. In the study group objectives for P&T and the boundary conditions of the phase out have been discussed. The fulfillment of the given objectives is analyzed from neutronics point of view using simulations of a molten salt reactor with fast neutron spectrum. It is shown that the efficient transmutation of all existing transuranium isotopes would be possible from neutronic point of view in a time frame of about 60 years. For this task three reactors of a mostly new technology would have to be developed and a twofold life cycle consisting of a transmuter operation and a deep burn phase would be required. A basic insight for the optimization of the time duration of the deep burn phase is given. Further on, a detailed balance of different isotopic inventories is given to allow a deeper understanding of the processes during transmutation in the molten salt fast reactor. The effect of modeling and simulation is investigated based on three different modeling strategies and two different code versions.

Statistical Transmutation in Floquet Driven Optical Lattices.

PubMed

Sedrakyan, Tigran A; Galitski, Victor M; Kamenev, Alex

2015-11-06

We show that interacting bosons in a periodically driven two dimensional (2D) optical lattice may effectively exhibit fermionic statistics. The phenomenon is similar to the celebrated Tonks-Girardeau regime in 1D. The Floquet band of a driven lattice develops the moat shape, i.e., a minimum along a closed contour in the Brillouin zone. Such degeneracy of the kinetic energy favors fermionic quasiparticles. The statistical transmutation is achieved by the Chern-Simons flux attachment similar to the fractional quantum Hall case. We show that the velocity distribution of the released bosons is a sensitive probe of the fermionic nature of their stationary Floquet state.

Accelerator-driven Transmutation of Waste

NASA Astrophysics Data System (ADS)

Venneri, Francesco

1998-04-01

Nuclear waste from commercial power plants contains large quantities of plutonium, other fissionable actinides, and long-lived fission products that are potential proliferation concerns and create challenges for the long-term storage. Different strategies for dealing with nuclear waste are being followed by various countries because of their geologic situations and their views on nuclear energy, reprocessing and non-proliferation. The current United States policy is to store unprocessed spent reactor fuel in a geologic repository. Other countries are opting for treatment of nuclear waste, including partial utilization of the fissile material contained in the spent fuel, prior to geologic storage. Long-term uncertainties are hampering the acceptability and eventual licensing of a geologic repository for nuclear spent fuel in the US, and driving up its cost. The greatest concerns are with the potential for radiation release and exposure from the spent fuel for tens of thousands of years and the possible diversion and use of the actinides contained in the waste for weapons construction. Taking advantage of the recent breakthroughs in accelerator technology and of the natural flexibility of subcritical systems, the Accelerator-driven Transmutation of Waste (ATW) concept offers the United States and other countries the possibility to greatly reduce plutonium, higher actinides and environmentally hazardous fission products from the waste stream destined for permanent storage. ATW does not eliminate the need for, but instead enhances the viability of permanent waste repositories. Far from being limited to waste destruction, the ATW concept also brings to the table new technologies that could be relevant for next-generation power producing reactors. In the ATW concept, spent fuel would be shipped to the ATW site where the plutonium, transuranics and selected long-lived fission products would be destroyed by fission or transmutation in their first and only pass through the

Transuranic inventory reduction in repository by partitioning and transmutation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kang, C.H.; Kazimi, M.S.

1992-01-01

The promise of a new reprocessing technology and the issuance of Environmental Protection Agency (EPA) and U.S. Nuclear Regulatory Commission regulations concerning a geologic repository rekindle the interest in partitioning and transmutation of transuranic (TRU) elements from discharged reactor fuel as a high level waste management option. This paper investigates the TRU repository inventory reduction capability of the proposed advanced liquid metal reactors (ALMRs) and integral fast reactors (IFRs) as well as the plutonium recycled light water reactors (LWRs).

Transmutation of All German Transuranium under Nuclear Phase Out Conditions – Is This Feasible from Neutronic Point of View?

PubMed Central

Merk, Bruno; Litskevich, Dzianis

2015-01-01

The German government has decided for the nuclear phase out, but a decision on a strategy for the management of the highly radioactive waste is not defined yet. Partitioning and Transmutation (P&T) could be considered as a technological option for the management of highly radioactive waste, therefore a wide study has been conducted. In the study group objectives for P&T and the boundary conditions of the phase out have been discussed. The fulfillment of the given objectives is analyzed from neutronics point of view using simulations of a molten salt reactor with fast neutron spectrum. It is shown that the efficient transmutation of all existing transuranium isotopes would be possible from neutronic point of view in a time frame of about 60 years. For this task three reactors of a mostly new technology would have to be developed and a twofold life cycle consisting of a transmuter operation and a deep burn phase would be required. A basic insight for the optimization of the time duration of the deep burn phase is given. Further on, a detailed balance of different isotopic inventories is given to allow a deeper understanding of the processes during transmutation in the molten salt fast reactor. The effect of modeling and simulation is investigated based on three different modeling strategies and two different code versions. PMID:26717509

Copper doping of ZnO crystals by transmutation of 64Zn to 65Cu: An electron paramagnetic resonance and gamma spectroscopy study

NASA Astrophysics Data System (ADS)

Recker, M. C.; McClory, J. W.; Holston, M. S.; Golden, E. M.; Giles, N. C.; Halliburton, L. E.

2014-06-01

Transmutation of 64Zn to 65Cu has been observed in a ZnO crystal irradiated with neutrons. The crystal was characterized with electron paramagnetic resonance (EPR) before and after the irradiation and with gamma spectroscopy after the irradiation. Major features in the gamma spectrum of the neutron-irradiated crystal included the primary 1115.5 keV gamma ray from the 65Zn decay and the positron annihilation peak at 511 keV. Their presence confirmed the successful transmutation of 64Zn nuclei to 65Cu. Additional direct evidence for transmutation was obtained from the EPR of Cu2+ ions (where 63Cu and 65Cu hyperfine lines are easily resolved). A spectrum from isolated Cu2+ (3d9) ions acquired after the neutron irradiation showed only hyperfine lines from 65Cu nuclei. The absence of 63Cu lines in this Cu2+ spectrum left no doubt that the observed 65Cu signals were due to transmuted 65Cu nuclei created as a result of the neutron irradiation. Small concentrations of copper, in the form of Cu+-H complexes, were inadvertently present in our as-grown ZnO crystal. These Cu+-H complexes are not affected by the neutron irradiation, but they dissociate when a crystal is heated to 900 °C. This behavior allowed EPR to distinguish between the copper initially in the crystal and the copper subsequently produced by the neutron irradiation. In addition to transmutation, a second major effect of the neutron irradiation was the formation of zinc and oxygen vacancies by displacement. These vacancies were observed with EPR.

Detection of endogenous lithium in neuropsychiatric disorders--a model for biological transmutation.

PubMed

Kurup, Ravi Kumar; Kurup, Parameswara Achutha

2002-01-01

The human hypothalamus produces an endogenous membrane Na(+)-K(+) ATPase inhibitor, digoxin. A digoxin induced model of cellular/neuronal quantal state and perception has been described by the authors. Biological transmutation has been described in microbial systems in the quantal state. The study focuses on the plasma levels of digoxin, RBC membrane Na(+)-K(+) ATPase activity, plasma levels of magnesium and lithium in neuropsychiatric and systemic disorders. Inhibition of RBC membrane Na(+)-K(+) ATPase activity was observed in most cases along with an increase in the levels of serum digoxin and lithium and a decrease in the level of serum Mg(++). The generation of endogenous lithium would obviously occur due to biological transmutation from magnesium. Digoxin and lithium together can produce added membrane Na(+)-K(+) ATPase inhibition. The role of membrane Na(+)-K(+) ATPase inhibition in the pathogenesis of neuropsychiatric and systemic disorders is discussed. The inhibition of membrane Na(+)-K(+) ATPase can contribute to an increase in intracellular calcium and a decrease in magnesium, which can result in a defective neurotransmitter transport mechanism, mitochondrial dysfunction and apoptosis, defective golgi body function and protein processing dysfunction, immune dysfunction and oncogenesis. Copyright 2002 John Wiley & Sons, Ltd.

[Separation of the effects of transmutation and radiation after incorporation of radionuclides into DNA (author's transl)].

PubMed

Hamann, H J; Irskens, M

1975-01-01

Among the various methods for studying the relative effects of transmutation and radiation of incorporated nuclides, simulation of beta radiation by external gamma exposure is of practical importance. Self-irradiation and mutual irradiation of the labeled cells cannot be neglected in any case. Furthermore, additional hypothetical and experimental problems may arise from using either external beta radiation or different isotopes of an element. By means of external gamma irradiation on the other hand, this being equivalent to the internal beta radiation from a microdosimetrical point of view, the radiation effect of the nuclide alone can be observed without any modification of other experimental parameters. To determine such equivalent gamma radiation for labeled cell nuclei of Vicia faba roots, the authors applied the Monte Carlo Method to the beta spectra of 32-P, 3-H, 14-C and 131-J, to the energy-dependent LET and to different cell diameters. The existence of secondary particle equilibrium inside the nuclei during gamma exposure was assumed. For certain radionuclides and cell sizes it is possible to calculate gamma spectra which induce energy spectra in the nuclei similar to those caused by the beta particles originating in the nuclear DNA.

Georgia Institute of Technology research on the Gas Core Actinide Transmutation Reactor (GCATR)

NASA Technical Reports Server (NTRS)

Clement, J. D.; Rust, J. H.; Schneider, A.; Hohl, F.

1976-01-01

The program reviewed is a study of the feasibility, design, and optimization of the GCATR. The program is designed to take advantage of initial results and to continue work carried out on the Gas Core Breeder Reactor. The program complements NASA's program of developing UF6 fueled cavity reactors for power, nuclear pumped lasers, and other advanced technology applications. The program comprises: (1) General Studies--Parametric survey calculations performed to examine the effects of reactor spectrum and flux level on the actinide transmutation for GCATR conditions. The sensitivity of the results to neutron cross sections are to be assessed. Specifically, the parametric calculations of the actinide transmutation are to include the mass, isotope composition, fission and capture rates, reactivity effects, and neutron activity of recycled actinides. (2) GCATR Design Studies--This task is a major thrust of the proposed research program. Several subtasks are considered: optimization criteria studies of the blanket and fuel reprocessing, the actinide insertion and recirculation system, and the system integration. A brief review of the background of the GCATR and ongoing research is presented.

Potential benefits of waste transmutation to the U.S. high-level waste respository

DOE Office of Scientific and Technical Information (OSTI.GOV)

Michaels, G.E.

1995-10-01

This paper reexamines the potential benefits of waste transmutation to the proposed U.S. geologic repository at the Yucca Mountain site based on recent progress in the performance assessment for the Yucca Mountain base case of spent fuel emplacement. It is observed that actinides are assumed to have higher solubility than in previous studies and that Np and other actinides now dominate the projected aqueous releases from a Yucca Mountain repository. Actinides are also indentified as the dominant source of decay heat in the repository, and the effect of decay heat in perturbing the hydrology, geochemistry, and thermal characteristics of Yuccamore » Mountain are reviewed. It is concluded that the potential for thermally-driven, buoyant, gas-phase flow at Yucca Mountain introduces data and modeling requirements that will increase the costs of licensing the site and may cause the site to be unattractive for geologic disposal of wastes. A transmutation-enabled cold repository is proposed that might allow licensing of a repository to be based upon currently observable characteristics of the Yucca Mountain site.« less

The physics design of accelerator-driven transmutation systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Venneri, F.

1995-10-01

Nuclear systems under study in the Los Alamos Accelerator-Driven Transmutation Technology program (ADTT) will allow the destruction of nuclear spent fuel and weapons-return plutonium, as well as the production of nuclear energy from the thorium cycle, without a long-lived radioactive waste stream. The subcritical systems proposed represent a radical departure from traditional nuclear concepts (reactors), yet the actual implementation of ADTT systems is based on modest extrapolations of existing technology. These systems strive to keep the best that the nuclear technology has developed over the years, within a sensible conservative design envelope and eventually manage to offer a safe, lessmore » expensive and more environmentally sound approach to nuclear power.« less

Transmutation of Radioactive Nuclear Waste — Present Status and Requirement for the Problem-Oriented Nuclear Database: Approach to Scheduling the Experiments (Reactor, Target, Blanket)

NASA Astrophysics Data System (ADS)

Artisyuk, V.; Ignatyuk, A.; Korovin, Yu.; Lopatkin, A.; Matveenko, I.; Stankovskiy, A.; Titarenko, Yu.

2005-05-01

Transmutation of nuclear wastes (Minor Actinides and Long-Lived Fission Products) remains an important option to reduce the burden of high-level waste on final waste disposal in deep geological structures. Accelerator-Driven Systems (ADS) are considered as possible candidates to perform transmutation due to their subcritical operation mode that eliminates some of the serious safety penalties unavoidable in critical reactors. Specific requirements to nuclear data necessary for ADS transmutation analysis is the main subject of the ISTC Project ♯2578 which started in 2004 to identify the areas of research priorities in the future. The present paper gives a summary of ongoing project stressing the importance of nuclear data for blanket performance (reactivity behavior with associated safety characteristics) and uncertainties that affect characteristics of neutron producing target.

Transmutation Scoping Studies for a Chloride Molten Salt Reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heidet, Florent; Feng, Bo; Kim, Taek

2016-01-01

Over the past few years, there has been strong renewed interest from private industry, mostly from start-up enterprises, in molten salt reactor (MSR) technologies because of the unique properties of this class of reactors. These are reactors in which the fuel is homogeneously mixed with the coolant in the form of liquid salts and is circulated continuously into and out of the active core region with on-line fuel management, salt treatment, and salt processing. In response to such wide-spread interest, Argonne National Laboratory is expanding its well-established reactor modelling and simulation expertise and infrastructure to enable detailed analysis and designmore » of MSRs. The tools being developed are able to simulate the continuous fuel flow, the complex on-line fuel management and elemental removal processes (e.g., fission product removal) using depletion steps representative of a real MSR system. Leveraging these capabilities, a parametric study on the transmutation performance of a simplified actinide-burning MSR concept that uses a chloride-based salt was performed. This type of salt has attracted attention over the more commonly discussed fluoride-based salts since no tritium is produced as a result of irradiation and it is compatible with a fast neutron spectrum. The studies discussed in this paper examine the performance of a burner MSR design with a fixed core size and power density over a range of possible fuel salt molar ratios with NaCl-MgCl2 as the carrier salt. The intent is to quantify the impact on the required transuranics content of the make-up fuel, the actinide transmutation rates, and other performance characteristics for typical burner MSR designs.« less

Analyses of transients for an 800 MW-class accelerator driven transmuter with fertile-free fuels

NASA Astrophysics Data System (ADS)

Maschek, Werner; Suzuki, Tohru; Chen, Xue-Nong; Rineiski, Andrei; Matzerath Boccaccini, Claudia; Mori, Magnus; Morita, Koji

2006-06-01

In the FUTURE Program, the development and application of fertile-free fuels for Accelerator Driven Transmuters (ADTs) has been advanced. To assess the reactor performance and safety behavior of an ADT with so-called dedicated fuels, various transient cases for an 800 MW-class Pb/Bi-cooled ADT were investigated using the SIMMER-III code. The FUTURE ADT also served as vehicle to develop and test ideas on a safety concept for such transmuters. After an extensive ranking procedure, a CERCER fuel with an MgO matrix and a CERMET fuel with a Mo-92 matrix were chosen. The transient scenarios shown here are: spurious beam trip (BT), unprotected loss of flow (ULOF) and unprotected blockage accident (UBA). Since the release of fission gas and helium after cladding failure could induce a significant positive reactivity, the gas-blowdown was investigated for the transient scenarios. The present analyses showed that power excursions could be avoided by the fuel sweep-out from the core under severe accident conditions.

Neutron Transmutation Doped (NTD) germanium thermistors for sub-mm bolometer applications

NASA Technical Reports Server (NTRS)

Haller, E. E.; Itoh, K. M.; Beeman, J. W.

1996-01-01

Recent advances in the development of neutron transmutation doped (NTD) semiconductor thermistors fabricated from natural and controlled isotopic composition germanium are reported. The near ideal doping uniformity that can be achieved with the NTD process, the device simplicity of NTD Ge thermistors and the high performance of cooled junction field effect transistor preamplifiers led to the widespread acceptance of these thermal sensors in ground-based, airborne and spaceborne radio telescopes. These features made possible the development of efficient bolometer arrays.

Practising alchemy: the transmutation of evidence into best health care.

PubMed

Goodyear-Smith, Felicity

2011-04-01

Alchemy was the synthesis or transmutation of all elements in perfect balance to obtain the philosopher's stone, the key to health. Just as alchemists sought this, so health practitioners always seek the best possible practice for optimal health outcomes for our patients. Best practice requires full knowledge--a little information can be dangerous. We need to serve our apprenticeship before we master our profession. Our profession is about improving health care. While the journey may start at medical school, the learning never ceases. It is not only about practising medicine, it is about the development of the practitioner. Professional practice requires systematic thinking combined with capacity to deal morally and creatively in areas of complexity and uncertainty appropriate to a specific context. It requires exemplary communication skills to interact with patients to facilitate collaborative decision making resulting in best practice. The synthesis of scientific and contextual evidence is a concept which applies to all disciplines where theoretical knowledge needs to be transferred to action to inform best practice. Decisions need to be made which take into account a complex array of factors, such as social and legal issues and resource constraints. Therefore, journey towards best practice involves transmutation of these three elements: scientific knowledge, the context in which it is applied and phronesis, the practical wisdom of the practitioner. All science has its limitations and we can never know all possible contextual information. Hence, like the philosopher's stone, best practice is a goal to which we aspire but never quite attain.

Scent Transmutation: A New Way to Teach on Chemical Equilibrium, Distillation, and Dynamic Combinatorial Chemistry

ERIC Educational Resources Information Center

Ji, Qing; El-Hamdi, Nadia S.; Miljanic´, Ognjen S?.

2014-01-01

Esters are volatile and pleasantly smelling compounds, commonly used as food additives. Using Ti(OBu)[subscript 4]-catalyzed acyl exchange, we demonstrate a scent transmutation experiment, in which two fragrant esters swap their acyl and alkoxy substituents and are, during the course of a reactive distillation, quantitatively converted into two…

Muonic alchemy: Transmuting elements with the inclusion of negative muons

NASA Astrophysics Data System (ADS)

Moncada, Félix; Cruz, Daniel; Reyes, Andrés

2012-06-01

In this Letter we present a theoretical study of atoms in which one electron has been replaced by a negative muon. We have treated these muonic systems with the Any Particle Molecular Orbital (APMO) method. A comparison between the electronic and muonic radial distributions revealed that muons are much more localized than electrons. Therefore, the muonic cloud is screening effectively one positive charge of the nucleus. Our results have revealed that by replacing an electron in an atom by a muon there is a transmutation of the electronic properties of that atom to those of the element with atomic number Z - 1.

From teosinte to maize: the catastrophic sexual transmutation.

PubMed

Iltis, H H

1983-11-25

An alternative to the theory that the ear of maize (Zea mays ssp. mays) evolved from a slender female ear of a Mexican annual teosinte holds that it was derived from the central spike of a male teosinte inflorescence (tassel) which terminates the primary lateral branches. This alternative hypothesis is more consistent with morphology and explains the anomalous lack of significant genetic and biochemical differences between these taxa. Maize, the only cereal with unisexual inflorescences, evolved through a sudden epigenetic sexual transmutation involving condensation of primary branches, which brought their tassels into the zone of female expression, leading to strong apical dominance and a catastrophic shift in nutrient allocation. Initially, this quantum change may have involved no new mutations, but rather genetic assimilation under human selection of an abnormality, perhaps environmentally triggered.

The Joint Institute for Nuclear Research in Experimental Physics of Elementary Particles

NASA Astrophysics Data System (ADS)

Bednyakov, V. A.; Russakovich, N. A.

2018-05-01

The year 2016 marks the 60th anniversary of the Joint Institute for Nuclear Research (JINR) in Dubna, an international intergovernmental organization for basic research in the fields of elementary particles, atomic nuclei, and condensed matter. Highly productive advances over this long road clearly show that the international basis and diversity of research guarantees successful development (and maintenance) of fundamental science. This is especially important for experimental research. In this review, the most significant achievements are briefly described with an attempt to look into the future (seven to ten years ahead) and show the role of JINR in solution of highly important problems in elementary particle physics, which is a fundamental field of modern natural sciences. This glimpse of the future is full of justified optimism.

Analysis and optimization of minor actinides transmutation blankets with regards to neutron and gamma sources

NASA Astrophysics Data System (ADS)

Kooymana, Timothée; Buiron, Laurent; Rimpault, Gérald

2017-09-01

Heterogeneous loading of minor actinides in radial blankets is a potential solution to implement minor actinides transmutation in fast reactors. However, to compensate for the lower flux level experienced by the blankets, the fraction of minor actinides to be loaded in the blankets must be increased to maintain acceptable performances. This severely increases the decay heat and neutron source of the blanket assemblies, both before and after irradiation, by more than an order of magnitude in the case of neutron source for instance. We propose here to implement an optimization methodology of the blankets design with regards to various parameters such as the local spectrum or the mass to be loaded, with the objective of minimizing the final neutron source of the spent assembly while maximizing the transmutation performances of the blankets. In a first stage, an analysis of the various contributors to long and short term neutron and gamma source is carried out while in a second stage, relevant estimators are designed for use in the effective optimization process, which is done in the last step. A comparison with core calculations is finally done for completeness and validation purposes. It is found that the use of a moderated spectrum in the blankets can be beneficial in terms of final neutron and gamma source without impacting minor actinides transmutation performances compared to more energetic spectrum that could be achieved using metallic fuel for instance. It is also confirmed that, if possible, the use of hydrides as moderating material in the blankets is a promising option to limit the total minor actinides inventory in the fuel cycle. If not, it appears that focus should be put upon an increased residence time for the blankets rather than an increase in the acceptable neutron source for handling and reprocessing.

Transmutation effects on long-term Cs retention in phyllosilicate minerals from first principles.

PubMed

Sassi, Michel; Okumura, Masahiko; Machida, Masahiko; Rosso, Kevin M

2017-10-11

The accidental release and incorporation of radiocesium into soil minerals represents a massive environmental, technical and social challenge. Accurately forecasting the evolving distribution and fate of long- and medium-lived isotopes such as 137 Cs and 134 Cs over decadal time scales is essential. The cesium cation has long been modeled as a strongly and selectively sorbed species into clay mineral interlayers; however, because of the time scales involved by the radioisotopes half-lives, the effects of radioactive decay on Cs retention have been unknown. We report density functional theory (DFT) simulations of transmutation effects of radiocesium on long-term Cs retention in phlogopite. The calculations show that the progressive appearance of daughter product Ba 2+ is accompanied by a proportional increase in thermodynamic driving force to preferentially discharge remaining Cs, both radioactive and stable, back into aqueous solution. Based on thermodynamic analysis, the findings indicate that radiocesium transmutation provides a mean to weaken the binding of Cs in phyllosilicate minerals, therefore potentially involving a premature re-release of Cs back into the environment. In the case where radiogenic Ba 2+ ions accumulate in the mineral, collateral effects would ultimately be an increase in the overall interlayer binding energy and a lower resorption capacity.

Monitoring of the Irradiated Neutron Fluence in the Neutron Transmutation Doping Process of Hanaro

NASA Astrophysics Data System (ADS)

Kim, Myong-Seop; Park, Sang-Jun

2009-08-01

Neutron transmutation doping (NTD) for silicon is a process of the creation of phosphorus impurities in intrinsic or extrinsic silicon by neutron irradiation to obtain silicon semiconductors with extremely uniform dopant distribution. HANARO has two vertical holes for the NTD, and the irradiation for 5 and 6 inch silicon ingots has been going on at one hole. In order to achieve the accurate neutron fluence corresponding to the target resistivity, the real time neutron flux is monitored by self-powered neutron detectors. After irradiation, the total irradiation fluence is confirmed by measuring the absolute activity of activation detectors. In this work, a neutron fluence monitoring method using zirconium foils with the mass of 10 ~ 50 mg was applied to the NTD process of HANARO. We determined the proportional constant of the relationship between the resistivity of the irradiated silicon and the neutron fluence determined by using zirconium foils. The determined constant for the initially n-type silicon was 3.126 × 1019 n·Ω/cm. It was confirmed that the difference between this empirical value and the theoretical one was only 0.5%. Conclusively, the practical methodology to perform the neutron transmutation doping of silicon was established.

Transmutation approximations for the application of hybrid Monte Carlo/deterministic neutron transport to shutdown dose rate analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Biondo, Elliott D.; Wilson, Paul P. H.

In fusion energy systems (FES) neutrons born from burning plasma activate system components. The photon dose rate after shutdown from resulting radionuclides must be quantified. This shutdown dose rate (SDR) is calculated by coupling neutron transport, activation analysis, and photon transport. The size, complexity, and attenuating configuration of FES motivate the use of hybrid Monte Carlo (MC)/deterministic neutron transport. The Multi-Step Consistent Adjoint Driven Importance Sampling (MS-CADIS) method can be used to optimize MC neutron transport for coupled multiphysics problems, including SDR analysis, using deterministic estimates of adjoint flux distributions. When used for SDR analysis, MS-CADIS requires the formulation ofmore » an adjoint neutron source that approximates the transmutation process. In this work, transmutation approximations are used to derive a solution for this adjoint neutron source. It is shown that these approximations are reasonably met for typical FES neutron spectra and materials over a range of irradiation scenarios. When these approximations are met, the Groupwise Transmutation (GT)-CADIS method, proposed here, can be used effectively. GT-CADIS is an implementation of the MS-CADIS method for SDR analysis that uses a series of single-energy-group irradiations to calculate the adjoint neutron source. For a simple SDR problem, GT-CADIS provides speedups of 200 100 relative to global variance reduction with the Forward-Weighted (FW)-CADIS method and 9 ± 5 • 104 relative to analog. As a result, this work shows that GT-CADIS is broadly applicable to FES problems and will significantly reduce the computational resources necessary for SDR analysis.« less

Transmutation approximations for the application of hybrid Monte Carlo/deterministic neutron transport to shutdown dose rate analysis

DOE PAGES

Biondo, Elliott D.; Wilson, Paul P. H.

2017-05-08

In fusion energy systems (FES) neutrons born from burning plasma activate system components. The photon dose rate after shutdown from resulting radionuclides must be quantified. This shutdown dose rate (SDR) is calculated by coupling neutron transport, activation analysis, and photon transport. The size, complexity, and attenuating configuration of FES motivate the use of hybrid Monte Carlo (MC)/deterministic neutron transport. The Multi-Step Consistent Adjoint Driven Importance Sampling (MS-CADIS) method can be used to optimize MC neutron transport for coupled multiphysics problems, including SDR analysis, using deterministic estimates of adjoint flux distributions. When used for SDR analysis, MS-CADIS requires the formulation ofmore » an adjoint neutron source that approximates the transmutation process. In this work, transmutation approximations are used to derive a solution for this adjoint neutron source. It is shown that these approximations are reasonably met for typical FES neutron spectra and materials over a range of irradiation scenarios. When these approximations are met, the Groupwise Transmutation (GT)-CADIS method, proposed here, can be used effectively. GT-CADIS is an implementation of the MS-CADIS method for SDR analysis that uses a series of single-energy-group irradiations to calculate the adjoint neutron source. For a simple SDR problem, GT-CADIS provides speedups of 200 100 relative to global variance reduction with the Forward-Weighted (FW)-CADIS method and 9 ± 5 • 104 relative to analog. As a result, this work shows that GT-CADIS is broadly applicable to FES problems and will significantly reduce the computational resources necessary for SDR analysis.« less

Impact of Including Higher Actinides in Fast Reactor Transmutation Analyses

DOE Office of Scientific and Technical Information (OSTI.GOV)

B. Forget; M. Asgari; R. Ferrer

2007-09-01

Previous fast reactor transmutation studies generally disregarded higher mass minor actinides beyond Cm-246 due to various considerations including deficiencies in nuclear cross-section data. Although omission of these higher mass actinides does not significantly impact the neutronic calculations and fuel cycle performance parameters follow-on neutron dose calculations related to fuel recycling, transportation and handling are significantly impacted. This report shows that including the minor actinides in the equilibrium fast reactor calculations will increase the predicted neutron emission by about 30%. In addition a sensitivity study was initiated by comparing the impact of different cross-section evaluation file for representing these minor actinides.

XVI Workshop on High Energy Spin Physics (D-SPIN2015)

NASA Astrophysics Data System (ADS)

Lednicky, Richard

2016-02-01

Dear Colleagues, Ladies and Gentlemen, on behalf of the Directorate of Joint Institute for Nuclear Research (JINR) it is a pleasure for me to welcome you here to Dubna for the 16th International Workshop on High Energy Spin Physics. It provides an opportunity to present and discuss the news accumulated during last year. Another important feature of this series of workshops has always been the participation of a large number of physicists from the former Soviet Union and Eastern European countries, for which long trips have previously been limited by financial (and earlier also by bureaucratic) reasons. It thus represents an important addition to the series of large International Symposia on spin physics held in even-numbered years in different countries, including the Symposium held in Dubna in 2012. JINR has a long-lasting tradition of experimental and theoretical studies of spin phenomena. The workshops on high energy spin physics started in Dubna in 1981 due to the initiative of L. Lapidus, an outstanding theoretical physicist. Since then, these meetings have been held in Dubna in every odd year and have become regular thanks to Anatoly Vasilievich Efremov, the chairman for many years. Recent years have brought a lot of new experimental results, and above all the discovery and determination of quantum characteristics of the Higgs boson at the Large Hadron Collider.

Monte carlo simulations of Yttrium reaction rates in Quinta uranium target

NASA Astrophysics Data System (ADS)

Suchopár, M.; Wagner, V.; Svoboda, O.; Vrzalová, J.; Chudoba, P.; Tichý, P.; Kugler, A.; Adam, J.; Závorka, L.; Baldin, A.; Furman, W.; Kadykov, M.; Khushvaktov, J.; Solnyshkin, A.; Tsoupko-Sitnikov, V.; Tyutyunnikov, S.; Bielewicz, M.; Kilim, S.; Strugalska-Gola, E.; Szuta, M.

2017-03-01

The international collaboration Energy and Transmutation of Radioactive Waste (E&T RAW) performed intensive studies of several simple accelerator-driven system (ADS) setups consisting of lead, uranium and graphite which were irradiated by relativistic proton and deuteron beams in the past years at the Joint Institute for Nuclear Research (JINR) in Dubna, Russia. The most recent setup called Quinta, consisting of natural uranium target-blanket and lead shielding, was irradiated by deuteron beams in the energy range between 1 and 8 GeV in three accelerator runs at JINR Nuclotron in 2011 and 2012 with yttrium samples among others inserted inside the setup to measure the neutron flux in various places. Suitable activation detectors serve as one of possible tools for monitoring of proton and deuteron beams and for measurements of neutron field distribution in ADS studies. Yttrium is one of such suitable materials for monitoring of high energy neutrons. Various threshold reactions can be observed in yttrium samples. The yields of isotopes produced in the samples were determined using the activation method. Monte Carlo simulations of the reaction rates leading to production of different isotopes were performed in the MCNPX transport code and compared with the experimental results obtained from the yttrium samples.

Progress on inert matrix fuels for minor actinide transmutation in fast reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bonnerot, Jean-Marc; Ferroud-Plattet, Marie-Pierre; Lamontagne, Jerome

2007-07-01

An extensive irradiation program has been devoted by CEA to the assessment of transmutation using minor actinide bearing inert support targets. A first irradiation experiment was performed in the fast neutron reactor Phenix, in parallel to other experiments carried out in the HFR and Siloe reactors, in order to assess the behavior under fast neutron flux of various materials intended as inert support matrix for transmutation targets. This experiment, which included the two steps MATINA 1 and MATINA 1A, was completed in 2004 and underwent complete post irradiation examinations (PIE) , whose results are presented in this paper. All themore » pure inert materials showed a satisfactory behavior under fast neutrons except Al{sub 2}O{sub 3} - which exhibits a swelling close to 11 vol. % after irradiation. In presence of UO{sub 2} fissile particles, MgAl{sub 2}O{sub 4} proved to be more stable in term of swelling as inert support than MgO and Al{sub 2}O{sub 3} matrices, under the same irradiation conditions. A second experiment ECRIX H in Phenix involving composite pellets with an MgO matrix and AmO{sub 2-x} particles was completed in 2006. The very first PIE results on ECRIX H are described in this paper. At the light of these first experiments, a second phase dedicated to the design optimization of the target was initiated and three new irradiation experiments - MATINA 2-3, CAMIX COCHIX in Phenix and HELIOS in HFR - were started in 2006 and 2007. (authors)« less

The Changes of Energy Interactions between Nucleus Function and Mitochondria Functions Causing Transmutation of Chronic Inflammation into Cancer Metabolism.

PubMed

Ponizovskiy, Michail R

2016-01-01

Interactions between nucleus and mitochondria functions induce the mechanism of maintenance stability of cellular internal energy according to the first law of thermodynamics in able-bodied cells and changes the mechanisms of maintenance stability of cellular internal energy creating a transition stationary state of ablebodied cells into quasi-stationary pathologic states of acute inflammation transiting then into chronic inflammation and then transmuting into cancer metabolism. The mechanisms' influences of intruding etiologic pathologic agents (microbe, virus, etc.) lead to these changes of energy interactions between nucleus and mitochondria functions causing general acute inflammation, then passing into local chronic inflammation, and reversing into cancer metabolism transmutation. Interactions between biochemical processes and biophysical processes of cellular capacitors' operations create a supplementary mechanism of maintenance stability of cellular internal energy in the norm and in pathology. Discussion of some scientific works eliminates doubts of the authors of these works.

Hardening neutron spectrum for advanced actinide transmutation experiments in the ATR.

PubMed

Chang, G S; Ambrosek, R G

2005-01-01

The most effective method for transmuting long-lived isotopes contained in spent nuclear fuel into shorter-lived fission products is in a fast neutron spectrum reactor. In the absence of a fast test reactor in the United States, initial irradiation testing of candidate fuels can be performed in a thermal test reactor that has been modified to produce a test region with a hardened neutron spectrum. Such a test facility, with a spectrum similar but somewhat softer than that of the liquid-metal fast breeder reactor (LMFBR), has been constructed in the INEEL's Advanced Test Reactor (ATR). The radial fission power distribution of the actinide fuel pin, which is an important parameter in fission gas release modelling, needs to be accurately predicted and the hardened neutron spectrum in the ATR and the LMFBR fast neutron spectrum is compared. The comparison analyses in this study are performed using MCWO, a well-developed tool that couples the Monte Carlo transport code MCNP with the isotope depletion and build-up code ORIGEN-2. MCWO analysis yields time-dependent and neutron-spectrum-dependent minor actinide and Pu concentrations and detailed radial fission power profile calculations for a typical fast reactor (LMFBR) neutron spectrum and the hardened neutron spectrum test region in the ATR. The MCWO-calculated results indicate that the cadmium basket used in the advanced fuel test assembly in the ATR can effectively depress the linear heat generation rate in the experimental fuels and harden the neutron spectrum in the test region.

Transmutation of Isotopes --- Ecological and Energy Production Aspects

NASA Astrophysics Data System (ADS)

Gudowski, Waclaw

2000-01-01

This paper describes principles of Accelerator-Driven Transmutation of Nuclear Wastes (ATW) and gives some flavour of the most important topics which are today under investigations in many countries. An assessment of the potential impact of ATW on a future of nuclear energy is also given. Nuclear reactors based on self-sustained fission reactions --- after spectacular development in fifties and sixties, that resulted in deployment of over 400 power reactors --- are wrestling today more with public acceptance than with irresolvable technological problems. In a whole spectrum of reasons which resulted in today's opposition against nuclear power few of them are very relevant for the nuclear physics community and they arose from the fact that development of nuclear power had been handed over to the nuclear engineers and technicians with some generically unresolved problems, which should have been solved properly by nuclear scientists. In a certain degree of simplification one can say, that most of the problems originate from very specific features of a fission phenomenon: self-sustained chain reaction in fissile materials and very strong radioactivity of fission products and very long half-life of some of the fission and activation products. And just this enormous concentration of radioactive fission products in the reactor core is the main problem of managing nuclear reactors: it requires unconditional guarantee for the reactor core integrity in order to avoid radioactive contamination of the environment; it creates problems to handle decay heat in the reactor core and finally it makes handling and/or disposal of spent fuel almost a philosophical issue, due to unimaginable long time scales of radioactive decay of some isotopes. A lot can be done to improve the design of conventional nuclear reactors (like Light Water Reactors); new, better reactors can be designed but it seems today very improbable to expect any radical change in the public perception of conventional

Preliminary Analysis of High-Flux RSG-GAS to Transmute Am-241 of PWR’s Spent Fuel in Asian Region

NASA Astrophysics Data System (ADS)

Budi Setiawan, M.; Kuntjoro, S.

2018-02-01

A preliminary study of minor actinides (MA) transmutation in the high flux profile RSG-GAS research reactor was performed, aiming at an optimal transmutation loading for present nuclear energy development. The MA selected in the analysis includes Am-241 discharged from pressurized water reactors (PWRs) in Asian region. Until recently, studies have been undertaken in various methods to reduce radiotoxicity from actinides in high-level waste. From the cell calculation using computer code SRAC2006, it is obtained that the target Am-241 which has a cross section of the thermal energy absorption in the region (group 8) is relatively large; it will be easily burned in the RSG-GAS reactor. Minor actinides of Am-241 which can be inserted in the fuel (B/T fuel) is 2.5 kg which is equivalent to Am-241 resulted from the partition of spent fuel from 2 units power reactors PWR with power 1000MW(th) operated for one year.

Electron teleportation and statistical transmutation in multiterminal Majorana islands

NASA Astrophysics Data System (ADS)

Michaeli, Karen; Landau, L. Aviad; Sela, Eran; Fu, Liang

2017-11-01

We study a topological superconductor island with spatially separated Majorana modes coupled to multiple normal-metal leads by single-electron tunneling in the Coulomb blockade regime. We show that low-temperature transport in such a Majorana island is carried by an emergent charge-e boson composed of a Majorana mode and an electronic excitation in leads. This transmutation from Fermi to Bose statistics has remarkable consequences. For noninteracting leads, the system flows to a non-Fermi-liquid fixed point, which is stable against tunnel couplings anisotropy or detuning away from the charge-degeneracy point. As a result, the system exhibits a universal conductance at zero temperature, which is a fraction of the conductance quantum, and low-temperature corrections with a universal power-law exponent. In addition, we consider Majorana islands connected to interacting one-dimensional leads, and find different stable fixed points near and far from the charge-degeneracy point.

Vaporisation of candidate nuclear fuels and targets for transmutation of minor actinides

NASA Astrophysics Data System (ADS)

Gotcu-Freis, P.; Hiernaut, J.-P.; Colle, J.-Y.; Nästrén, C.; Carretero, A. Fernandez; Konings, R. J. M.

2011-04-01

The thermal stability and high temperature behaviour of candidate fuels and targets for transmutation of minor actinides has been investigated. Zirconia-based solid solution, MgO-based CERCER and molybdenum-based CERMET fuels containing Am and/or Pu in various concentrations were heated up to 2700 K in a Knudsen cell coupled with a quadrupole mass spectrometer, to measure their vapour pressure and vapour composition. The results reveal that the vaporisation of the actinides from the samples is not only determined by the thermodynamics of the system but is also related to the dynamic evolution of multi-component mixtures with complex composition or microstructure.

Transmutation of skyrmions to half-solitons driven by the nonlinear optical spin Hall effect.

PubMed

Flayac, H; Solnyshkov, D D; Shelykh, I A; Malpuech, G

2013-01-04

We show that the spin domains, generated in the linear optical spin Hall effect by the analog of spin-orbit interaction for exciton polaritons, are associated with the formation of a Skyrmion lattice. In the nonlinear regime, the spin anisotropy of the polariton-polariton interactions results in a spatial compression of the domains and in a transmutation of the Skyrmions into oblique half-solitons. This phase transition is associated with both the focusing of the spin currents and the emergence of a strongly anisotropic emission pattern.

Multiple rod-cone and cone-rod photoreceptor transmutations in snakes: evidence from visual opsin gene expression.

PubMed

Simões, Bruno F; Sampaio, Filipa L; Loew, Ellis R; Sanders, Kate L; Fisher, Robert N; Hart, Nathan S; Hunt, David M; Partridge, Julian C; Gower, David J

2016-01-27

In 1934, Gordon Walls forwarded his radical theory of retinal photoreceptor 'transmutation'. This proposed that rods and cones used for scotopic and photopic vision, respectively, were not fixed but could evolve into each other via a series of morphologically distinguishable intermediates. Walls' prime evidence came from series of diurnal and nocturnal geckos and snakes that appeared to have pure-cone or pure-rod retinas (in forms that Walls believed evolved from ancestors with the reverse complement) or which possessed intermediate photoreceptor cells. Walls was limited in testing his theory because the precise identity of visual pigments present in photoreceptors was then unknown. Subsequent molecular research has hitherto neglected this topic but presents new opportunities. We identify three visual opsin genes, rh1, sws1 and lws, in retinal mRNA of an ecologically and taxonomically diverse sample of snakes central to Walls' theory. We conclude that photoreceptors with superficially rod- or cone-like morphology are not limited to containing scotopic or photopic opsins, respectively. Walls' theory is essentially correct, and more research is needed to identify the patterns, processes and functional implications of transmutation. Future research will help to clarify the fundamental properties and physiology of photoreceptors adapted to function in different light levels. © 2016 The Author(s).

New Mechanism of Low Energy Nuclear Reactions Using Superlow

NASA Astrophysics Data System (ADS)

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

2006-03-01

We proposed a new mechanism of LENR (low energy nuclear reactions) cooperative processes in the whole system - nuclei+atoms+condensed matter can occur at smaller threshold than the corresponding ones assoiciated with free constituents. The cooperative processes can be induced and enhanced by (``superlow energy'') external fields. The excess heat is the emission of internal energy, and transmutations from LENR are the result of redistribution of the internal energy of the whole system. A review of possible stimulation mechanisms of LENR is presented. We have concluded that transmutation of nuclei at low energies and excess heat are possible in the framework of the known fundamental physical laws: The universal resonance synchronization principle, and based on it, different enhancement mechanisms of reaction rates are responsible for these processes. The excitation and ionization of atoms may play the role of a trigger for LENR. F.A. Gareev, I.E. Zhidkova, E-print arXiv Nucl-th/0511092 v1 30 Nov 2005. F.A. Gareev, In: FPB-98, Novosibirsk, June 1998, p.92; F.A.Gareev, G.F. Gareeva, in: Novosibirsk, July 2000, p.161. F.A. Gareev, I.E. Zhidkova and Yu.L. Ratis, Preprint JINR P4-2004-68, Dubna, 2004. F.A. Gareev, I.E. Zhidkova, E-print arXiv Nucl-th/0505021 9 May 2005.

Post-irradiation examinations of THERMHET composite fuels for transmutation

NASA Astrophysics Data System (ADS)

Noirot, J.; Desgranges, L.; Chauvin, N.; Georgenthum, V.

2003-07-01

The thermal behaviour of composite targets dedicated to minor actinide transmutation was studied using THERMHET (thermal behaviour of heterogeneous fuel) irradiation in the SILOE reactor. Three inert matrix fuel designs were tested (macro-mass, jingle and microdispersion) all with a MgAl 2O 4 spinel inert matrix and around 40% weight of UO 2 to simulate minor actinide inclusions. The post-irradiation examinations led to a new interpretation of the temperature measurement by thermocouples located in the central hole of the pellets. A major change in the micro-dispersed structure was detected. The examinations enabled us to understand the behaviour of the spinel during the different stages of irradiation. They revealed an amorphisation at low temperature and then a nano re-crystallisation at high temperature of the spinel in the micro-dispersed case. These results, together with those obtained in the MATINA irradiation of an equivalent structure, show the importance of the irradiation temperature on spinel behaviour.

Study of radioactive impurities in neutron transmutation doped germanium

NASA Astrophysics Data System (ADS)

Mathimalar, S.; Dokania, N.; Singh, V.; Nanal, V.; Pillay, R. G.; Shrivastava, A.; Jagadeesan, K. C.; Thakare, S. V.

2015-02-01

A program to develop low temperature (mK) sensors with neutron transmutation doped Ge for rare event studies with a cryogenic bolometer has been initiated. For this purpose, semiconductor grade Ge wafers are irradiated with thermal neutron flux from Dhruva reactor at Bhabha Atomic Research Centre (BARC), Mumbai. Spectroscopic studies of irradiated samples have revealed that the environment of the capsule used for irradiating the sample leads to significant levels of 65Zn, 110mAg and 182Ta impurities, which can be reduced by chemical etching of approximately 50 μm thick surface layer. From measurements of the etched samples in the low background counting setup, activity due to trace impurities of 123Sb in bulk Ge is estimated to be 1 Bq / g after irradiation. These estimates indicate that in order to use the NTD Ge sensors for rare event studies, a cooldown period of 2 years would be necessary to reduce the radioactive background to ≤ 1 mBq / g.

Georgia Tech Studies of Sub-Critical Advanced Burner Reactors with a D-T Fusion Tokamak Neutron Source for the Transmutation of Spent Nuclear Fuel

NASA Astrophysics Data System (ADS)

Stacey, W. M.

2009-09-01

The possibility that a tokamak D-T fusion neutron source, based on ITER physics and technology, could be used to drive sub-critical, fast-spectrum nuclear reactors fueled with the transuranics (TRU) in spent nuclear fuel discharged from conventional nuclear reactors has been investigated at Georgia Tech in a series of studies which are summarized in this paper. It is found that sub-critical operation of such fast transmutation reactors is advantageous in allowing longer fuel residence time, hence greater TRU burnup between fuel reprocessing stages, and in allowing higher TRU loading without compromising safety, relative to what could be achieved in a similar critical transmutation reactor. The required plasma and fusion technology operating parameter range of the fusion neutron source is generally within the anticipated operational range of ITER. The implications of these results for fusion development policy, if they hold up under more extensive and detailed analysis, is that a D-T fusion tokamak neutron source for a sub-critical transmutation reactor, built on the basis of the ITER operating experience, could possibly be a logical next step after ITER on the path to fusion electrical power reactors. At the same time, such an application would allow fusion to contribute to meeting the nation's energy needs at an earlier stage by helping to close the fission reactor nuclear fuel cycle.

Gas core reactors for actinide transmutation. [uranium hexafluoride

NASA Technical Reports Server (NTRS)

Clement, J. D.; Rust, J. H.; Wan, P. T.; Chow, S.

1979-01-01

The preliminary design of a uranium hexafluoride actinide transmutation reactor to convert long-lived actinide wastes to shorter-lived fission product wastes was analyzed. It is shown that externally moderated gas core reactors are ideal radiators. They provide an abundant supply of thermal neutrons and are insensitive to composition changes in the blanket. For the present reactor, an initial load of 6 metric tons of actinides is loaded. This is equivalent to the quantity produced by 300 LWR-years of operation. At the beginning, the core produces 2000 MWt while the blanket generates only 239 MWt. After four years of irradiation, the actinide mass is reduced to 3.9 metric tonnes. During this time, the blanket is becoming more fissile and its power rapidly approaches 1600 MWt. At the end of four years, continuous refueling of actinides is carried out and the actinide mass is held constant. Equilibrium is essentially achieved at the end of eight years. At equilibrium, the core is producing 1400 MWt and the blanket 1600 MWt. At this power level, the actinide destruction rate is equal to the production rate from 32 LWRs.

Clustering of transmutation elements tantalum, rhenium and osmium in tungsten in a fusion environment

NASA Astrophysics Data System (ADS)

You, Yu-Wei; Kong, Xiang-Shan; Wu, Xuebang; Liu, C. S.; Fang, Q. F.; Chen, J. L.; Luo, G.-N.

2017-08-01

The formation of transmutation solute-rich precipitates has been reported to seriously degrade the mechanical properties of tungsten in a fusion environment. However, the underlying mechanisms controlling the formation of the precipitates are still unknown. In this study, first-principles calculations are therefore performed to systemically determine the stable structures and binding energies of solute clusters in tungsten consisting of tantalum, rhenium and osmium atoms as well as irradiation-induced vacancies. These clusters are known to act as precursors for the formation of precipitates. We find that osmium can easily segregate to form clusters even in defect-free tungsten alloys, whereas extremely high tantalum and rhenium concentrations are required for the formation of clusters. Vacancies greatly facilitate the clustering of rhenium and osmium, while tantalum is an exception. The binding energies of vacancy-osmium clusters are found to be much higher than those of vacancy-tantalum and vacancy-rhenium clusters. Osmium is observed to strongly promote the formation of vacancy-rhenium clusters, while tantalum can suppress the formation of vacancy-rhenium and vacancy-osmium clusters. The local strain and electronic structure are analyzed to reveal the underlying mechanisms governing the cluster formation. Employing the law of mass action, we predict the evolution of the relative concentration of vacancy-rhenium clusters. This work presents a microscopic picture describing the nucleation and growth of solute clusters in tungsten alloys in a fusion reactor environment, and thereby explains recent experimental phenomena.

FIRST-PRINCIPLES CALCULATIONS OF CHARGE STATES AND FORMATION ENERGIES OF Mg, Al, and Be TRANSMUTANTS IN 3C-SiC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Shenyang Y.; Setyawan, Wahyu; Jiang, Weilin

2014-08-28

The Vienna Ab-initio Simulation Package (VASP) is employed to calculate charge states and the formation energies of Mg, Al and Be transmutants at different lattice sites in 3C-SiC. The results provide important information on the dependence of the most stable charge state and formation energy of Mg, Al, Be and vacancies on electron potentials.

An omnidirectional retroreflector based on the transmutation of dielectric singularities.

PubMed

Ma, Yun Gui; Ong, C K; Tyc, Tomás; Leonhardt, Ulf

2009-08-01

Transformation optics is a concept used in some metamaterials to guide light on a predetermined path. In this approach, the materials implement coordinate transformations on electromagnetic waves to create the illusion that the waves are propagating through a virtual space. Transforming space by appropriately designed materials makes devices possible that have been deemed impossible. In particular, transformation optics has led to the demonstration of invisibility cloaking for microwaves, surface plasmons and infrared light. Here, on the basis of transformation optics, we implement a microwave device that would normally require a dielectric singularity, an infinity in the refractive index. To fabricate such a device, we transmute a dielectric singularity in virtual space into a mere topological defect in a real metamaterial. In particular, we demonstrate an omnidirectional retroreflector, a device for faithfully reflecting images and for creating high visibility from all directions. Our method is robust, potentially broadband and could also be applied to visible light using similar techniques.

Robert Boyle, Transmutation, and the History of Chemistry before Lavoisier: A Response to Kuhn.

PubMed

Newman, William R

2014-01-01

In an influential article of 1952, Thomas Kuhn argued that Robert Boyle had little or no influence on the subsequent development of chemistry. This essay challenges Kuhn's view on two fronts. First, it shows that Johann Joachim Becher developed his hierarchical matter theory under the influence of Boyle and then transmitted it to the founder of the phlogiston theory, G. E. Stahl. Second, this essay argues that transmutational matter theories were not necessarily opposed to the existence of stable chemical species, pace Kuhn. Boyle's corpuscular theory descended largely from the tradition of "chymical atomism," which often advocated both chrysopoeia and the reality of robust chemical substances.

Development of Metallic Fuels for Actinide Transmutation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hayes, Steven Lowe; Fielding, Randall Sidney; Benson, Michael Timothy

Research and development activities on metallic fuels are focused on their potential use for actinide transmutation in future sodium fast reactors. As part of this application, there is also a need for a near zero-loss fabrication process and a desire to demonstrate a multifold increase in burnup potential. The incorporation of Am and Np into the traditional U-20Pu-10Zr metallic fuel alloy was demonstrated in the US during the Integral Fast Reactor Program of the 1980’s and early 1990’s. However, the conventional counter gravity injection casting method performed under vacuum, previously used to fabricate these metallic fuel alloys, was not optimizedmore » for mitigating loss of the volatile Am constituent in the casting charge; as a result, approximately 40% of the Am casting charge failed to be incorporated into the as-cast fuel alloys. Fabrication development efforts of the past few years have pursued an optimized bottom-pour casting method to increase utilization of the melted charge to near 100%, and a differential pressure casting approach, performed under an argon overpressure, has been demonstrated to result in essentially no loss of Am due to volatilization during fabrication. In short, a path toward zero-loss fabrication of metallic fuels including minor actinides has been shown to be feasible. Irradiation testing of advanced metallic fuel alloys in the Advanced Test Reactor (ATR) has been underway since 2003. Testing in the ATR is performed inside of cadmium-shrouded positions to remove >99% of the thermal flux incident on the test fuels, resulting in an epi-thermal driven fuel test that is free from gross flux depression and producing an essentially prototypic radial temperature profile inside the fuel rodlets. To date, three irradiation test series (AFC-1,2,3) have been completed. Over 20 different metallic fuel alloys have been tested to burnups as high as 30% with constituent compositions of Pu up to 30%, Am up to 12%, Np up to 10%, and Zr

Correlations, soliton modes, and non-Hermitian linear mode transmutation in the one-dimensional noisy Burgers equation.

PubMed

Fogedby, Hans C

2003-08-01

Using the previously developed canonical phase space approach applied to the noisy Burgers equation in one dimension, we discuss in detail the growth morphology in terms of nonlinear soliton modes and superimposed linear modes. We moreover analyze the non-Hermitian character of the linear mode spectrum and the associated dynamical pinning, and mode transmutation from diffusive to propagating behavior induced by the solitons. We discuss the anomalous diffusion of growth modes, switching and pathways, correlations in the multisoliton sector, and in detail the correlations and scaling properties in the two-soliton sector.

Reliability assessment of MVP-BURN and JENDL-4.0 related to nuclear transmutation of light platinum group elements

NASA Astrophysics Data System (ADS)

Terashima, Atsunori; Nilsson, Mikael; Ozawa, Masaki; Chiba, Satoshi

2017-09-01

The Aprés ORIENT research program, as a concept of advanced nuclear fuel cycle, was initiated in FY2011 aiming at creating stable, highly-valuable elements by nuclear transmutation from ↓ssion products. In order to simulate creation of such elements by (n, γ) reaction succeeded by β- decay in reactors, a continuous-energy Monte Carlo burnup calculation code MVP-BURN was employed. Then, it is one of the most important tasks to con↓rm the reliability of MVP-BURN code and evaluated neutron cross section library. In this study, both an experiment of neutron activation analysis in TRIGA Mark I reactor at University of California, Irvine and the corresponding burnup calculation using MVP-BURN code were performed for validation of the simulation on transmutation of light platinum group elements. Especially, some neutron capture reactions such as 102Ru(n, γ)103Ru, 104Ru(n, γ)105Ru, and 108Pd(n, γ)109Pd were dealt with in this study. From a comparison between the calculation (C) and the experiment (E) about 102Ru(n, γ)103Ru, the deviation (C/E-1) was signi↓cantly large. Then, it is strongly suspected that not MVP-BURN code but the neutron capture cross section of 102Ru belonging to JENDL-4.0 used in this simulation have made the big di↑erence as (C/E-1) >20%.

Ionizing radiation and tritium transmutation both cause formation of 5-hydroxymethyl-2'-deoxyuridine in cellular DNA.

PubMed Central

Teebor, G W; Frenkel, K; Goldstein, M S

1984-01-01

HeLa cells grown in the presence of [methyl-3H]thymidine contained large amounts of 5-hydroxymethyl-2'-deoxyuridine (HMdU) in their DNA. When the cells were grown in [6-3H]thymidine and their DNA was labeled to the same specific activity, no HMdU was present. When such [6-3H]thymidine-labeled cells were exposed to increasing amounts of gamma-radiation, small but increasing amounts of HMdU were formed in their DNA. This indicates that HMdU can be formed in DNA by two distinct mechanisms. The first is the result of the transmutation of 3H to 3He (beta decay) in the methyl group of thymidine, leading to formation of a carbocation. This short-lived ion reacts with hydroxide ions of water, yielding the hydroxymethyl group. HMdU that is formed by this mechanism is formed at the rate of beta decay of 3H. It appears only in [methyl-3H]thymidine residues and is present in the DNA of both nonirradiated and gamma-irradiated cells. The second mechanism is the result of the radiolysis of water caused by ionizing radiation. The resultant radical species, particularly hydroxyl radicals, may react with many sites on DNA. When the methyl group of thymine is attacked by hydroxyl radicals, the hydroxymethyl group is formed. The formation of HMdU by this mechanism was detected only when [6-3H]thymidine-labeled cells were used, since transmutation of 3H in position 6 of thymine cannot yield HMdU. PMID:6582490

Ionizing radiation and tritium transmutation both cause formation of 5-hydroxymethyl-2'-deoxyuridine in cellular DNA.

PubMed

Teebor, G W; Frenkel, K; Goldstein, M S

1984-01-01

HeLa cells grown in the presence of [methyl-3H]thymidine contained large amounts of 5-hydroxymethyl-2'-deoxyuridine (HMdU) in their DNA. When the cells were grown in [6-3H]thymidine and their DNA was labeled to the same specific activity, no HMdU was present. When such [6-3H]thymidine-labeled cells were exposed to increasing amounts of gamma-radiation, small but increasing amounts of HMdU were formed in their DNA. This indicates that HMdU can be formed in DNA by two distinct mechanisms. The first is the result of the transmutation of 3H to 3He (beta decay) in the methyl group of thymidine, leading to formation of a carbocation. This short-lived ion reacts with hydroxide ions of water, yielding the hydroxymethyl group. HMdU that is formed by this mechanism is formed at the rate of beta decay of 3H. It appears only in [methyl-3H]thymidine residues and is present in the DNA of both nonirradiated and gamma-irradiated cells. The second mechanism is the result of the radiolysis of water caused by ionizing radiation. The resultant radical species, particularly hydroxyl radicals, may react with many sites on DNA. When the methyl group of thymine is attacked by hydroxyl radicals, the hydroxymethyl group is formed. The formation of HMdU by this mechanism was detected only when [6-3H]thymidine-labeled cells were used, since transmutation of 3H in position 6 of thymine cannot yield HMdU.

Plasmon transmutation: inducing new modes in nanoclusters by adding dielectric nanoparticles.

PubMed

Wen, Fangfang; Ye, Jian; Liu, Na; Van Dorpe, Pol; Nordlander, Peter; Halas, Naomi J

2012-09-12

Planar clusters of coupled plasmonic nanoparticles support nanoscale electromagnetic "hot spots" and coherent effects, such as Fano resonances, with unique near and far field signatures, currently of prime interest for sensing applications. Here we show that plasmonic cluster properties can be substantially modified by the addition of individual, discrete dielectric nanoparticles at specific locations on the cluster, introducing new plasmon modes, or transmuting existing plasmon modes to new ones, in the resulting metallodielectric nanocomplex. Depositing a single carbon nanoparticle in the junction between a pair of adjacent nanodisks induces a metal-dielectric-metal quadrupolar plasmon mode. In a ten-membered cluster, placement of several carbon nanoparticles in junctions between multiple adjacent nanoparticles introduces a collective magnetic plasmon mode into the Fano dip, giving rise to an additional subradiant mode in the metallodielectric nanocluster response. These examples illustrate that adding dielectric nanoparticles to metallic nanoclusters expands the number and types of plasmon modes supported by these new mixed-media nanoscale assemblies.

Modulated electromagnetic fields in inhomogeneous media, hyperbolic pseudoanalytic functions, and transmutations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khmelnytskaya, Kira V., E-mail: khmel@uaq.edu.mx; Kravchenko, Vladislav V., E-mail: vkravchenko@math.cinvestav.edu.mx; Torba, Sergii M., E-mail: storba@math.cinvestav.edu.mx

2016-05-15

The time-dependent Maxwell system describing electromagnetic wave propagation in inhomogeneous isotropic media in the one-dimensional case reduces to a Vekua-type equation for bicomplex-valued functions of a hyperbolic variable, see Kravchenko and Ramirez [Adv. Appl. Cliord Algebr. 21(3), 547–559 (2011)]. Using this relation, we solve the problem of the transmission through an inhomogeneous layer of a normally incident electromagnetic time-dependent plane wave. The solution is written in terms of a pair of Darboux-associated transmutation operators [Kravchenko, V. V. and Torba, S. M., J. Phys. A: Math. Theor. 45, 075201 (2012)], and combined with the recent results on their construction [Kravchenko, V.more » V. and Torba, S. M., Complex Anal. Oper. Theory 9, 379-429 (2015); Kravchenko, V. V. and Torba, S. M., J. Comput. Appl. Math. 275, 1–26 (2015)] can be used for efficient computation of the transmitted modulated signals. We develop the corresponding numerical method and illustrate its performance with examples.« less

Radiological assessment of target materials for accelerator transmutation of waste (ATW) applications

NASA Astrophysics Data System (ADS)

Vickers, Linda Diane

This dissertation issues the first published document of the radiation absorbed dose rate (rad-h-1) to tissue from radioactive spallation products in Ta, W, Pb, Bi, and LBE target materials used in Accelerator Transmutation of Waste (ATW) applications. No previous works have provided an estimate of the absorbed dose rate (rad-h-1) from activated targets for ATW applications. The results of this dissertation are useful for planning the radiological safety assessment to personnel, and for the design, construction, maintenance, and disposition of target materials of high-energy particle accelerators for ATW applications (Charlton, 1996). In addition, this dissertation provides the characterization of target materials of high-energy particle accelerators for the parameters of: (1) spallation neutron yield (neutrons/proton), (2) spallation products yield (nuclides/proton), (3) energy-dependent spallation neutron fluence distribution, (4) spallation neutron flux, (5) identification of radioactive spallation products for consideration in safety of personnel to high radiation dose rates, and (6) identification of the optimum geometrical dimensions for the target applicable to the maximum radial spallation neutron leakage from the target. Pb and Bi target materials yielded the lowest absorbed dose rates (rad-h -1) for a 10-year irradiation/50-year decay scheme, and would be the preferred target materials for consideration of the radiological safety of personnel during ATW operations. A beneficial characteristic of these target materials is that they do not produce radioactive transuranic isotopes, which have very long half-lives and require special handling and disposition requirements. Furthermore, the targets are not considered High-Level Waste (HLW) such as reactor spent fuel for disposal purposes. It is a basic ATW system requirement that the spallation target after it has been expended should be disposable as Class C low-level radioactive waste. Therefore, the disposal

ADS Model in the TIRELIRE-STRATEGIE Fuel Cycle Simulation Code Application to Minor Actinides Transmutation Studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garzenne, Claude; Massara, Simone; Tetart, Philippe

2006-07-01

Accelerator Driven Systems offer the advantage, thanks to the core sub-criticality, to burn highly radioactive elements such as americium and curium in a dedicated stratum, and then to avoid polluting with these elements the main part of the nuclear fleet, which is optimized for electricity production. This paper presents firstly the ADS model implemented in the fuel cycle simulation code TIRELIRE-STRATEGIE that we developed at EDF R and D Division for nuclear power scenario studies. Then we show and comment the results of TIRELIRE-STRATEGIE calculation of a transition scenario between the current French nuclear fleet, and a fast reactor fleetmore » entirely deployed towards the end of the 21. century, consistently with the EDF prospective view, with 3 options for the minor actinides management:1) vitrified with fission products to be sent to the final disposal; 2) extracted together with plutonium from the spent fuel to be transmuted in Generation IV fast reactors; 3) eventually extracted separately from plutonium to be incinerated in a ADSs double stratum. The comparison of nuclear fuel cycle material fluxes and inventories between these options shows that ADSs are not more efficient than critical fast reactors for reducing the high level waste radio-toxicity; that minor actinides inventory and fluxes in the fuel cycle are more than twice as high in case of a double ADSs stratum than in case of minor actinides transmutation in Generation IV FBRs; and that about fourteen 400 MWth ADS are necessary to incinerate minor actinides issued from a 60 GWe Generation IV fast reactor fleet, corresponding to the current French nuclear fleet installed power. (authors)« less

A beamline systems model for Accelerator-Driven Transmutation Technology (ADTT) facilities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Todd, A.M.M.; Paulson, C.C.; Peacock, M.A.

1995-10-01

A beamline systems code, that is being developed for Accelerator-Driven Transmutation Technology (ADTT) facility trade studies, is described. The overall program is a joint Grumman, G.H. Gillespie Associates (GHGA) and Los Alamos National Laboratory effort. The GHGA Accelerator Systems Model (ASM) has been adopted as the framework on which this effort is based. Relevant accelerator and beam transport models from earlier Grumman systems codes are being adapted to this framework. Preliminary physics and engineering models for each ADTT beamline component have been constructed. Examples noted include a Bridge Coupled Drift Tube Linac (BCDTL) and the accelerator thermal system. A decisionmore » has been made to confine the ASM framework principally to beamline modeling, while detailed target/blanket, balance-of-plant and facility costing analysis will be performed externally. An interfacing external balance-of-plant and facility costing model, which will permit the performance of iterative facility trade studies, is under separate development. An ABC (Accelerator Based Conversion) example is used to highlight the present models and capabilities.« less

A beamline systems model for Accelerator-Driven Transmutation Technology (ADTT) facilities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Todd, Alan M. M.; Paulson, C. C.; Peacock, M. A.

1995-09-15

A beamline systems code, that is being developed for Accelerator-Driven Transmutation Technology (ADTT) facility trade studies, is described. The overall program is a joint Grumman, G. H. Gillespie Associates (GHGA) and Los Alamos National Laboratory effort. The GHGA Accelerator Systems Model (ASM) has been adopted as the framework on which this effort is based. Relevant accelerator and beam transport models from earlier Grumman systems codes are being adapted to this framework. Preliminary physics and engineering models for each ADTT beamline component have been constructed. Examples noted include a Bridge Coupled Drift Tube Linac (BCDTL) and the accelerator thermal system. Amore » decision has been made to confine the ASM framework principally to beamline modeling, while detailed target/blanket, balance-of-plant and facility costing analysis will be performed externally. An interfacing external balance-of-plant and facility costing model, which will permit the performance of iterative facility trade studies, is under separate development. An ABC (Accelerator Based Conversion) example is used to highlight the present models and capabilities.« less

Characterizing Background Events in Neutron Transmutation Doped Thermistors for CUORE-0

NASA Astrophysics Data System (ADS)

Dutta, Suryabrata; Cuore Collaboration

2017-09-01

The Cryogenic Underground Observatory for Rare Events (CUORE) is a ton-scale neutrinoless double-beta decay experiment operating at the Laboratori Nazionali del Gran Sasso (LNGS). The experiment is comprised of 988 TeO2 bolometric crystals arranged into 19 towers and operated at a temperature of 15 mK. A neutron-transmutation-doped (NTD) Ge thermistor measures the thermal response from particles incident on the crystals. However, bulk and surface contamination of the NTD thermistors themselves produce distorted thermal responses inside the thermistor volume. Although these pulses are efficiently removed from the double-beta decay analysis by pulse shape cuts, they can be used to extract information about thermistor contamination. I will present a multifaceted approach to characterize these events, in which I implement an improved hot-electron thermal model, Geant4 Monte Carlo simulations of background events, and data from a previous experiment, CUORE-0, reprocessed with a new optimal filter. Using this approach, rates and energy deposition from contamination inside the NTD thermistors are measured, giving us better understanding of a CUORE background source.

Transmutation studies at CEA in frame of the SPIN program objectives, results and future trends

DOE Office of Scientific and Technical Information (OSTI.GOV)

Salvatores, M.; Prunier, C.; Guerin, Y.

1995-10-01

In order to respond to the public concern about wastes and in particular the long-lived high level ones, a French law issued on December 30, 1991 identified the major objectives of research for the next fifteen years, before a new debate and possibly a decision on final wastes disposal in Parliament. These objectives are: (1) improvement of the wastes conditioning; (2) extraction and transmutation of the long-lived wastes in order to minimize their long term toxicity; (3) research performed in underground laboratories in order to characterize the capacity of geological structures to confine radioactive wastes (two sites have to bemore » selected for these underground laboratories, in concertation with the local population); (4) last, the study of conditioning and prolonged surface storage of wastes.« less

Transmutation of Personal Glucose Meters into Portable and Highly Sensitive Microbial Pathogen Detection Platform.

PubMed

Wang, Zhenzhen; Chen, Zhaowei; Gao, Nan; Ren, Jinsong; Qu, Xiaogang

2015-10-07

Herein, for the first time, we presented a simple and general approach by using personal glucose meters (PGM) for portable and ultrasensitive detection of microbial pathogens. Upon addition of pathogenic bacteria, glucoamylase-quaternized magnetic nanoparticles (GA-QMNPS) conjugates were disrupted by the competitive multivalent interactions between bacteria and QMNPS, resulting in the release of GA. After magnetic separation, the free GA could catalyze the hydrolysis of amylose into glucose for quantitative readout by PGM. In such way, PGM was transmuted into a bacterial detection device and extremely low detection limits down to 20 cells mL(-1) was achieved. More importantly, QMNPS could inhibit the growth of the bacteria and destroy its cellular structure, which enabled bacteria detection and inhibition simultaneously. The simplicity, portability, sensitivity and low cost of presented work make it attractive for clinical applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Closed DTU fuel cycle with Np recycle and waste transmutation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beller, D.E.; Sailor, W.C.; Venneri, F.

1999-09-01

A nuclear energy scenario for the 21st century that included a denatured thorium-uranium-oxide (DTU) fuel cycle and new light water reactors (LWRs) supported by accelerator-driven transmutation of waste (ATW) systems was previously described. This coupled system with the closed DTU fuel cycle provides several improvements beyond conventional LWR (CLWR) (once-through, UO{sub 2} fuel) nuclear technology: increased proliferation resistance, reduced waste, and efficient use of natural resources. However, like CLWR fuel cycles, the spent fuel in the first one-third core discharged after startup contains higher-quality Pu than the equilibrium fuel cycle. To eliminate this high-grade Pu, Np is separated and recycledmore » with Th and U--rather than with higher actinides [(HA) including Pu]. The presence of Np in the LWR feed greatly increases the production of {sup 238}Pu so that a few kilograms of Pu generated enough alpha-decay heat that the separated Pu is highly resistant to proliferation. This alternate process also simplifies the pyrochemical separation of fuel elements (Th and U) from HAs. To examine the advantages of this concept, the authors modeled a US deployment scenario for nuclear energy that includes DTU-LWRs plus ATW`s to burn the actinides produced by these LWRs and to close the back-end of the DTU fuel cycle.« less

Laser-Bioplasma Interaction: The Blood Type Transmutation Induced by Multiple Ultrashort Wavelength Laser Beams

NASA Astrophysics Data System (ADS)

Stefan, V. Alexander

2015-11-01

The interaction of ultrashort wavelength multi laser beams with the flowing blood thin films leads to the transmutation of the blood types A, B, and AB into O type. This is a novel mechanism of importance for the transfusion medicine. Laser radiation is in resonance with the eigen-frequency modes of the antigen proteins and forces the proteins to parametrically oscillate until they get kicked out from the surface. The stripping away of antigens is done by the scanning-multiple-lasers of a high repetition rate in the blue-purple frequency domain. The guiding-lasers are in the red-green frequency domain. The laser force, (parametric interaction with the antigen eigen-oscillation), upon the antigen protein molecule must exceed its weight. The scanning laser beam is partially reflected as long as the antigen(s) is not eliminated. The process of the protein detachment can last a few minutes. Supported by Nikola Tesla Labs., Stefan University.

Neutron transmutation doping of silicon in the SAFARI-1 research reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Louw, P.A.; Robertson, D.G.; Strydom, W.J.

1994-12-31

The SAFARI-1 research reactor has operated with an exemplary safety record since commissioning in 1965. As part of a commercialisation effort a silicon irradiation facility (SILIRAD) has been installed in the poolside region of SAFARI-1 for Neutron Transmutation Doping (NTD) of silicon. Commissioning of the facility took place in the last quarter of 1992 with a series of trial irradiations which were performed in close collaboration with Wacker Chemitronic of Germany. A methodology for the determination of irradiation times necessary to achieve the target resistivities was verified on the basis of the results from the trial irradiations. All production activitiesmore » are controlled by quality assurance procedures. To date some hundred and twelve silicon ingots (103 mm diameter) have been successfully irradiated on a commercial contract basis. The observed axial and radial variations in the resistivity profile of the ingots are very small compared to the profiles associated with conventionally doped silicon and small tolerances on target resistivities are attained. In this paper an overview of the design and characterisation of SILIRAD is given and the methods applied that ensure a quality product are described. Results obtained from trial and production irradiations are presented and the envisaged future modifications to SILIRAD discussed.« less

TANGRA - an experimental setup for basic and applied nuclear research by means of 14.1 MeV neutrons

NASA Astrophysics Data System (ADS)

Ruskov, Ivan; Kopatch, Yury; Bystritsky, Vyacheslav; Skoy, Vadim; Shvetsov, Valery; Hambsch, Franz-Josef; Oberstedt, Stephan; Noy, Roberto Capote; Grozdanov, Dimitar; Zontikov, Artem; Rogov, Yury; Zamyatin, Nikolay; Sapozhnikov, Mikhail; Slepnev, Vyacheslav; Bogolyubov, Evgeny; Sadovsky, Andrey; Barmakov, Yury; Ryzhkov, Valentin; Yurkov, Dimitry; Valković, Vladivoj; Obhođaš, Jasmina; Aliyev, Fuad

2017-09-01

For investigation of the basic characteristics of 14.1 MeV neutron induced nuclear reactions on a number of important isotopes for nuclear science and engineering, a new experimental setup TANGRA has been constructed at the Frank Laboratory of Neutron Physics of the Joint Institute for Nuclear Research in Dubna. For testing its performance, the angular distribution of γ-rays (and neutrons) from the inelastic scattering of 14.1 MeV neutrons on high-purity carbon was measured and the angular anisotropy of γ-rays from the reaction 12C(n, n'γ)12C was determined. This reaction is important from fundamental (differential cross-sections) and practical (non-destructive elemental analysis of materials containing carbon) point of view. The preliminary results for the anisotropy of the γ-ray emission from the inelastic scattering of 14.1- MeV neutrons on carbon are compared with already published literature data. A detailed data analysis for determining the correlations between inelastic scattered neutron and γ-ray emission will be published elsewhere.

Transmutation of singularities and zeros in graded index optical instruments: a methodology for designing practical devices.

PubMed

Hooper, I R; Philbin, T G

2013-12-30

We describe a design methodology for modifying the refractive index profile of graded-index optical instruments that incorporate singularities or zeros in their refractive index. The process maintains the device performance whilst resulting in graded profiles that are all-dielectric, do not require materials with unrealistic values, and that are impedance matched to the bounding medium. This is achieved by transmuting the singularities (or zeros) using the formalism of transformation optics, but with an additional boundary condition requiring the gradient of the co-ordinate transformation be continuous. This additional boundary condition ensures that the device is impedance matched to the bounding medium when the spatially varying permittivity and permeability profiles are scaled to realizable values. We demonstrate the method in some detail for an Eaton lens, before describing the profiles for an "invisible disc" and "multipole" lenses.

Investigation of total cross sections for reactions induced by {sup 6}He interaction with silicon nuclei at energies between 5 and 50 MeV/A

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kabdrakhimova, G. D., E-mail: gaukharkd@gmail.com; Sobolev, Yu. G.; Kuhtina, I. N.

2017-01-15

Experimental excitation functions in terms of the total cross sections for {sup 6}He + Si nuclear reactions are analyzed in the energy range between 5 and 50 MeV/A, and a brief survey of the procedures used to obtain experimental data is given. Particular attention is given to describing experiments performed in beams of radioactive nuclei from the accelerators of the Laboratory of Nuclear Reactions at the Joint Institute for Nuclear Research (JINR, Dubna). The experimental data in question are analyzed on the basis of a semimicroscopic optical model.

Multi-pass Monte Carlo simulation method in nuclear transmutations.

PubMed

Mateescu, Liviu; Kadambi, N Prasad; Ravindra, Nuggehalli M

2016-12-01

Monte Carlo methods, in their direct brute simulation incarnation, bring realistic results if the involved probabilities, be they geometrical or otherwise, remain constant for the duration of the simulation. However, there are physical setups where the evolution of the simulation represents a modification of the simulated system itself. Chief among such evolving simulated systems are the activation/transmutation setups. That is, the simulation starts with a given set of probabilities, which are determined by the geometry of the system, the components and by the microscopic interaction cross-sections. However, the relative weight of the components of the system changes along with the steps of the simulation. A natural measure would be adjusting probabilities after every step of the simulation. On the other hand, the physical system has typically a number of components of the order of Avogadro's number, usually 10 25 or 10 26 members. A simulation step changes the characteristics for just a few of these members; a probability will therefore shift by a quantity of 1/10 25 . Such a change cannot be accounted for within a simulation, because then the simulation should have then a number of at least 10 28 steps in order to have some significance. This is not feasible, of course. For our computing devices, a simulation of one million steps is comfortable, but a further order of magnitude becomes too big a stretch for the computing resources. We propose here a method of dealing with the changing probabilities, leading to the increasing of the precision. This method is intended as a fast approximating approach, and also as a simple introduction (for the benefit of students) in the very branched subject of Monte Carlo simulations vis-à-vis nuclear reactors. Copyright © 2016 Elsevier Ltd. All rights reserved.

Unifying Theory of Low-Energy Nuclear Reaction and Transmutation Processes in Deuterated/hydrogenated Metals, Acoustic Cavitation, Glow Discharge, and Deuteron Beam Experiments

NASA Astrophysics Data System (ADS)

Kim, Yeong E.; Zubarev, Alexander L.

The most basic theoretical challenge for understanding low-energy nuclear reaction (LENR) and transmutation reaction (LETR) in condensed matters is to find mechanisms by which the large Coulomb barrier between fusing nuclei can be overcome. A unifying theory of LENR and LETR has been developed to provide possible mechanisms for the LENR and LETR processes in matters based on high-density nano-scale and micro-scale quantum plasmas. It is shown that recently developed theoretical models based on Bose-Einstein Fusion (BEF) mechanism and Quantum Plasma Nuclear Fusion (QPNF) mechanism are applicable to the results of many different types of LENR and LETR experiments.

Integral nuclear data validation using experimental spent nuclear fuel compositions

DOE PAGES

Gauld, Ian C.; Williams, Mark L.; Michel-Sendis, Franco; ...

2017-07-19

Measurements of the isotopic contents of spent nuclear fuel provide experimental data that are a prerequisite for validating computer codes and nuclear data for many spent fuel applications. Under the auspices of the Organisation for Economic Co-operation and Development (OECD) Nuclear Energy Agency (NEA) and guidance of the Expert Group on Assay Data of Spent Nuclear Fuel of the NEA Working Party on Nuclear Criticality Safety, a new database of expanded spent fuel isotopic compositions has been compiled. The database, Spent Fuel Compositions (SFCOMPO) 2.0, includes measured data for more than 750 fuel samples acquired from 44 different reactors andmore » representing eight different reactor technologies. Measurements for more than 90 isotopes are included. This new database provides data essential for establishing the reliability of code systems for inventory predictions, but it also has broader potential application to nuclear data evaluation. Furthermore, the database, together with adjoint based sensitivity and uncertainty tools for transmutation systems developed to quantify the importance of nuclear data on nuclide concentrations, are described.« less

Integral nuclear data validation using experimental spent nuclear fuel compositions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gauld, Ian C.; Williams, Mark L.; Michel-Sendis, Franco

Measurements of the isotopic contents of spent nuclear fuel provide experimental data that are a prerequisite for validating computer codes and nuclear data for many spent fuel applications. Under the auspices of the Organisation for Economic Co-operation and Development (OECD) Nuclear Energy Agency (NEA) and guidance of the Expert Group on Assay Data of Spent Nuclear Fuel of the NEA Working Party on Nuclear Criticality Safety, a new database of expanded spent fuel isotopic compositions has been compiled. The database, Spent Fuel Compositions (SFCOMPO) 2.0, includes measured data for more than 750 fuel samples acquired from 44 different reactors andmore » representing eight different reactor technologies. Measurements for more than 90 isotopes are included. This new database provides data essential for establishing the reliability of code systems for inventory predictions, but it also has broader potential application to nuclear data evaluation. Furthermore, the database, together with adjoint based sensitivity and uncertainty tools for transmutation systems developed to quantify the importance of nuclear data on nuclide concentrations, are described.« less

Mixtures of Charged Bosons Confined in Harmonic Traps and Bose-Einstein Condensation Mechanism for Low-Energy Nuclear Reactions and Transmutation Processes in Condensed Matters

NASA Astrophysics Data System (ADS)

Kim, Yeong E.; Zubarev, Alexander L.

2006-02-01

A mixture of two different species of positively charged bosons in harmonic traps is considered in the mean-field approximation. It is shown that depending on the ratio of parameters, the two components may coexist in same regions of space, in spite of the Coulomb repulsion between the two species. Application of this result is discussed for the generalization of the Bose-Einstein condensation mechanism for low-energy nuclear reaction (LENR) and transmutation processes in condensed matters. For the case of deutron-lithium (d + Li) LENR, the result indicates that (d + 6Li) reactions may dominate over (d + d) reactions in LENR experiments.

Sensitivity Studies and Experimental Evaluation for Optimizing Transcurium Isotope Production

DOE PAGES

Hogle, Susan L.; Alexander, Charles W.; Burns, Jonathan D.; ...

2017-03-01

This work applies to recent initiatives at the Radiochemical Engineering Development Center at Oak Ridge National Laboratory to optimize the production of transcurium isotopes in the High Flux Isotope Reactor in such a way as to prolong the use of high quality heavy curium feedstock. By studying the sensitivity of fission and transmutation reaction rates to the neutron flux spectrum a means of increasing the fraction of (n,γ) reactions per neutron absorption is explored. Filter materials which preferentially absorb neutrons at energies considered detrimental to optimal transcurium production are identified and transmutation rates are examined with high energy resolution. Experimentalmore » capsules are irradiated employing filter materials and the resulting fission and activation products studied to validate the filtering methodology. Improvement is seen in the production efficiency of heavier curium isotopes in 244Cm and 245Cm targets, and potentially in production of 252Cf from mixed californium targets. Finally, further analysis is recommended to evaluate longer duration irradiations more representative of typical transcurium production.« less

Transmutation of a trans-series: the Gross-Witten-Wadia phase transition

NASA Astrophysics Data System (ADS)

Ahmed, Anees; Dunne, Gerald V.

2017-11-01

We study the change in the resurgent asymptotic properties of a trans-series in two parameters, a coupling g 2 and a gauge index N, as a system passes through a large N phase transition, using the universal example of the Gross-Witten-Wadia third-order phase transition in the unitary matrix model. This transition is well-studied in the immediate vicinity of the transition point, where it is characterized by a double-scaling limit Painlevé II equation, and also away from the transition point using the pre-string difference equation. Here we present a complementary analysis of the transition at all coupling and all finite N, in terms of a differential equation, using the explicit Tracy-Widom mapping of the Gross-Witten-Wadia partition function to a solution of a Painlevé III equation. This mapping provides a simple method to generate trans-series expansions in all parameter regimes, and to study their transmutation as the parameters are varied. For example, at any finite N the weak coupling expansion is divergent, with a non-perturbative trans-series completion; on the other hand, the strong coupling expansion is convergent, and yet there is still a non-perturbative trans-series completion. We show how the different instanton terms `condense' at the transition point to match with the double-scaling limit trans-series. We also define a uniform large N strong-coupling expansion (a non-linear analogue of uniform WKB), which is much more precise than the conventional large N expansion through the transition region, and apply it to the evaluation of Wilson loops.

Detecting neutrons by forward recoil protons at the Energy & Transmutation facility: Detector development and calibration with 14.1-MeV neutrons

NASA Astrophysics Data System (ADS)

Afanasev, S.; Vishnevskiy, A.; Vishnevskiy, D.; Rogachev, A.; Tyutyunnikov, S.

2017-05-01

As part of the Energy & Transmutation project, we are developing a detector for neutrons with energies in the 10-100 MeV range emitted from the target irradiated by a charged-particle beam. The neutron is detected by measuring the time-of-flight and total kinetic energy of the forward-going recoil proton [1] knocked out at a small angle from a thin layer of plastic scintillator, which has to be selected against an intense background created by γ quanta, scattered neutrons, and charged particles. On the other hand, neutron energy has to be measured over the full range with no extra tuning of the detector operation regime. Initial measurements with a source of 14.1-MeV neutrons are reported.

Design of Lead-Free Inorganic Halide Perovskites for Solar Cells via Cation-Transmutation.

PubMed

Zhao, Xin-Gang; Yang, Ji-Hui; Fu, Yuhao; Yang, Dongwen; Xu, Qiaoling; Yu, Liping; Wei, Su-Huai; Zhang, Lijun

2017-02-22

Hybrid organic-inorganic halide perovskites with the prototype material of CH 3 NH 3 PbI 3 have recently attracted intense interest as low-cost and high-performance photovoltaic absorbers. Despite the high power conversion efficiency exceeding 20% achieved by their solar cells, two key issues-the poor device stabilities associated with their intrinsic material instability and the toxicity due to water-soluble Pb 2+ -need to be resolved before large-scale commercialization. Here, we address these issues by exploiting the strategy of cation-transmutation to design stable inorganic Pb-free halide perovskites for solar cells. The idea is to convert two divalent Pb 2+ ions into one monovalent M + and one trivalent M 3+ ions, forming a rich class of quaternary halides in double-perovskite structure. We find through first-principles calculations this class of materials have good phase stability against decomposition and wide-range tunable optoelectronic properties. With photovoltaic-functionality-directed materials screening, we identify 11 optimal materials with intrinsic thermodynamic stability, suitable band gaps, small carrier effective masses, and low excitons binding energies as promising candidates to replace Pb-based photovoltaic absorbers in perovskite solar cells. The chemical trends of phase stabilities and electronic properties are also established for this class of materials, offering useful guidance for the development of perovskite solar cells fabricated with them.

Generation of Escher Arts with Dual Perception.

PubMed

Lin, Shih-Syun; Morace, Charles C; Lin, Chao-Hung; Hsu, Li-Fong; Lee, Tong-Yee

2018-02-01

Escher transmutation is a graphic art that smoothly transforms one tile pattern into another tile pattern with dual perception. A classic example is the artwork called Sky and Water, in which a compelling figure-ground arrangement is applied to portray the transmutation of a bird in sky and a fish in water. The shape of a bird is progressively deformed and dissolves into the background while the background gradually reveals the shape of a fish. This paper introduces a system to create a variety of Escher-like transmutations, which includes the algorithms for initializing a tile pattern with dual figure-ground arrangement, for searching for the best matched shape of a user-specified motif from a database, and for transforming the content and shapes of tile patterns using a content-aware warping technique. The proposed system, integrating the graphic techniques of tile initialization, shape matching, and shape warping, allows users to create various Escher-like transmutations with minimal user interaction. Experimental results and conducted user studies demonstrate the feasibility and flexibility of the proposed system in Escher art generation.

Exploring Chemical Space with the Alchemical Derivatives.

PubMed

Balawender, Robert; Welearegay, Meressa A; Lesiuk, Michał; De Proft, Frank; Geerlings, Paul

2013-12-10

In this paper, we verify the usefulness of the alchemical derivatives in the prediction of chemical properties. We concentrate on the stability of the transmutation products, where the term "transmutation" means the change of the nuclear charge at an atomic site at constant number of electrons. As illustrative transmutations showing the potential of the method in exploring chemical space, we present some examples of increasing complexity starting with the deprotonation, continuing with the transmutation of the nitrogen molecule, and ending with the substitution of isoelectronic B-N units for C-C units and N units for C-H units in carbocyclic systems. The basis set influence on the qualitative and quantitative accuracies of the alchemical predictions was investigated. The alchemical deprotonation energy (from the second order Taylor expansion) correlates well with the vertical deprotonation energy and can be used as a preliminary indicator for the experimental deprotonation energy. The results of calculations for the BN derivatives of benzene and pyrene show that this method has great potential for efficient and accurate scanning of chemical space.

The Existence of a Designer Al=Al Double Bond in the LiAl2 H4- Cluster Formed by Electronic Transmutation.

PubMed

Lundell, Katie A; Zhang, Xinxing; Boldyrev, Alexander I; Bowen, Kit H

2017-12-22

The Al=Al double bond is elusive in chemistry. Herein we report the results obtained via combined photoelectron spectroscopy and ab initio studies of the LiAl 2 H 4 - cluster that confirm the formation of a conventional Al=Al double bond. Comprehensive searches for the most stable structures of the LiAl 2 H 4 - cluster have shown that the global minimum isomer I possesses a geometric structure which resembles that of Si 2 H 4 , demonstrating a successful example of the transmutation of Al atoms into Si atoms by electron donation. Theoretical simulations of the photoelectron spectrum discovered the coexistence of two isomers in the ion beam, including the one with the Al=Al double bond. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Predicting thermo-mechanical behaviour of high minor actinide content composite oxide fuel in a dedicated transmutation facility

NASA Astrophysics Data System (ADS)

Lemehov, S. E.; Sobolev, V. P.; Verwerft, M.

2011-09-01

The European Facility for Industrial Transmutation (EFIT) of the minor actinides (MA), from LWR spent fuel is being developed in the integrated project EUROTRANS within the 6th Framework Program of EURATOM. Two composite uranium-free fuel systems, containing a large fraction of MA, are proposed as the main candidates: a CERCER with magnesia matrix hosting (Pu,MA)O 2-x particles, and a CERMET with metallic molybdenum matrix. The long-term thermal and mechanical behaviour of the fuel under the expected EFIT operating conditions is one of the critical issues in the core design. To make a reliable prediction of long-term thermo-mechanical behaviour of the hottest fuel rods in the lead-cooled version of EFIT with thermal power of 400 MW, different fuel performance codes have been used. This study describes the main results of modelling the thermo-mechanical behaviour of the hottest CERCER fuel rods with the fuel performance code MACROS which indicate that the CERCER fuel residence time can safely reach at least 4-5 effective full power years.

Transmutation and activation of reduced activation ferritic martensitic steel in molten salt cooled fusion power plants

NASA Astrophysics Data System (ADS)

Cheng, E. T.

2004-08-01

Neutron activation analysis was conducted for the reduced activation ferritic/martensitic (RAFM) steel used in flibe molten-salt cooled fusion blankets. After 22.4 MW yr/m 2 of neutron exposure, the RAFM steel first wall in a molten salt blanket with 40% lithium-6 enrichment in lithium was found to be within 1 mSv/h in contact dose rate after 100 yr of cooling. The contact dose rate drops to 30 and 20 μSv/h or less, respectively, when the cooling times are 300 and 500 yr after discharge. The RAFM steel discharged from the high-temperature shield component would be allowed for hands-on recycling after 100 yr of cooling, when the contact dose rate is 10 μSv/h or less. The most significant changes found in the RAFM steel first wall due to nuclear transmutation, are 10% decrease in W and 10% increase in Ti. Additionally, there are minor elements produced: Mn - <1.2%, V - <0.26%, Re - <0.2%, Ta - <0.08%, and Os - <0.1%, all in weight percent. The gaseous elements generated are H and He, and the, respectively, accumulated quantities are about 260 and 190 wppm.

[Lethal effect after transmutation of 33P incorporated into bacteriophage S 13 and mechanisms of DNA double helix rupture].

PubMed

Apelgot, S

1980-04-01

The experiments show the lethal effect of the beta decay of 33P incorporated in DNA of bacteriophage S 13. The lethal efficiency is high, 0.72 at 0 degrees C and 0.55 at--197 degrees C. The presence of a radical scavenger like AET has no influence. It was found previously that for such phages with single-stranded DNA, the lethal efficiency of 32P decay is unity, and that the lethal event is a DNA single-strand break, owing to the high energy of the nucleogenic 32S atom. As the recoil energy of the 33S atom is too low to account for such a break, it is suggested that the reorganization of the phosphate molecule into sulphate is able to bring about a DNA single-strand break with an efficiency as high as 0.7, at 0 degrees C. A model for the DNA double-strand-break produced by a transmutation processes is suggested.

A theoretical model for the production of Ac-225 for cancer therapy by neutron capture transmutation of Ra-226.

PubMed

Melville, G; Melville, P

2013-02-01

Radium needles that were once implanted into tumours as a cancer treatment are now obsolete and constitute a radioactive waste problem, as their half-life is 1600 years. We are investigating the reduction of radium by transmutation by bombarding Ra-226 with high-energy neutrons from a neutron source to produce Ra-225 and hence Ac-225, which can be used as a generator to produce Bi-213 for use in 'Targeted Alpha Therapy' for cancer. This paper examines the possibility of producing Ac-225 by neutron capture using a theoretical model in which neutron energy is convoluted with the corresponding neutron cross sections of Ra-226. The total integrated yield can then be obtained. This study shows that an intense beam of high-energy neutrons could initiate neutron capture on Ra-226 to produce Ra-225 and hence practical amounts of Ac-225 and a useful reduction of Ra-226. Copyright © 2012 Elsevier Ltd. All rights reserved.

Multiple rod–cone and cone–rod photoreceptor transmutations in snakes: Evidence from visual opsin gene expression

USGS Publications Warehouse

Simoe, Bruno F; Sampaio, Filipa L.; Loew, Ellis R.; Sanders, Kate L.; Fisher, Robert N.; Hart, Nathan S.; Hunt, David M.; Partridge, Julian C.; Gower, David J.

2016-01-01

In 1934, Gordon Walls forwarded his radical theory of retinal photoreceptor ‘transmutation’. This proposed that rods and cones used for scotopic and photopic vision, respectively, were not fixed but could evolve into each other via a series of morphologically distinguishable intermediates. Walls' prime evidence came from series of diurnal and nocturnal geckos and snakes that appeared to have pure-cone or pure-rod retinas (in forms that Walls believed evolved from ancestors with the reverse complement) or which possessed intermediate photoreceptor cells. Walls was limited in testing his theory because the precise identity of visual pigments present in photoreceptors was then unknown. Subsequent molecular research has hitherto neglected this topic but presents new opportunities. We identify three visual opsin genes, rh1, sws1 and lws, in retinal mRNA of an ecologically and taxonomically diverse sample of snakes central to Walls' theory. We conclude that photoreceptors with superficially rod- or cone-like morphology are not limited to containing scotopic or photopic opsins, respectively. Walls' theory is essentially correct, and more research is needed to identify the patterns, processes and functional implications of transmutation. Future research will help to clarify the fundamental properties and physiology of photoreceptors adapted to function in different light levels.

Multiple rod–cone and cone–rod photoreceptor transmutations in snakes: evidence from visual opsin gene expression

PubMed Central

Sampaio, Filipa L.; Loew, Ellis R.; Sanders, Kate L.; Fisher, Robert N.; Hart, Nathan S.; Hunt, David M.; Partridge, Julian C.

2016-01-01

In 1934, Gordon Walls forwarded his radical theory of retinal photoreceptor ‘transmutation’. This proposed that rods and cones used for scotopic and photopic vision, respectively, were not fixed but could evolve into each other via a series of morphologically distinguishable intermediates. Walls' prime evidence came from series of diurnal and nocturnal geckos and snakes that appeared to have pure-cone or pure-rod retinas (in forms that Walls believed evolved from ancestors with the reverse complement) or which possessed intermediate photoreceptor cells. Walls was limited in testing his theory because the precise identity of visual pigments present in photoreceptors was then unknown. Subsequent molecular research has hitherto neglected this topic but presents new opportunities. We identify three visual opsin genes, rh1, sws1 and lws, in retinal mRNA of an ecologically and taxonomically diverse sample of snakes central to Walls' theory. We conclude that photoreceptors with superficially rod- or cone-like morphology are not limited to containing scotopic or photopic opsins, respectively. Walls' theory is essentially correct, and more research is needed to identify the patterns, processes and functional implications of transmutation. Future research will help to clarify the fundamental properties and physiology of photoreceptors adapted to function in different light levels. PMID:26817768

ECHIC2013 Committees

NASA Astrophysics Data System (ADS)

2014-05-01

Editors: Giorgio Giardina (University of Messina), Avazbek K Nasirov (JINR of Dubna) and Giuseppe Mandaglio (CSFNSM of Catania) Chairman: Giorgio Giardina (Messina) Co-Chairman: Avazbek Nasirov (JINR-Dubna) Co-Chairman: Giuseppe Mandaglio (Messina) Co-Chairman: Katsuhisa Nishio (JAEA-Tokai) Scientific Secretaries: Francesca Curciarello and Veronica De Leo (Messina) Website: http://newcleo.unime.it/ECHIC2013 Further details of the committees and sponsors are available in the PDF

PROGRESS IN THE STUDY OF ION IRRADIATION IN TUNGSTEN

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiang, Weilin; Kruska, Karen; Henager, Charles H.

2017-02-27

The experimental study intends to generate data to validate the theoretical predictions on defect accumulation and recovery, as well as to investigate microstructural evolution and transmutant precipitation in mono- and poly-crystalline tungsten using ion implantation.

Effects of alloying and transmutation impurities on stability and mobility of helium in tungsten under a fusion environment

NASA Astrophysics Data System (ADS)

Wu, Xuebang; Kong, Xiang-Shan; You, Yu-Wei; Liu, C. S.; Fang, Q. F.; Chen, Jun-Ling; Luo, G.-N.; Wang, Zhiguang

2013-07-01

The behaviour of helium in metals is particularly significant in fusion research due to the He-induced degradation of materials. A small amount of impurities introduced either by intentional alloying or by transmutation reactions, will interact with He and lead the microstructure and mechanical properties of materials to change. In this paper, we present the results of first-principles calculations on the interactions of He with impurities and He diffusion around them in tungsten (W), including the interstitials Be, C, N, O, and substitutional solutes Re, Ta, Tc, Nb, V, Os, Ti, Si, Zr, Y and Sc. We find that the trapping radii of interstitial atoms on He are much larger than those of substitutional solutes. The binding energies between the substitutional impurities and He increase linearly with the relative charge densities at the He occupation site, indicating that He atoms easily aggregate at the low charge density site. The sequence of diffusion energy barriers of He around the possible alloying elements is Ti > V > Os > Ta > Re. The present results suggest that Ta might be chosen as a relatively suitable alloying element compared with other possible ones.

A theoretical model for the production of Ac-225 for cancer therapy by photon-induced transmutation of Ra-226.

PubMed

Melville, G; Fan Liu, Sau; Allen, B J

2006-09-01

Radium needles that were once implanted into tumours as a cancer treatment are now obsolete and constitute a radioactive waste problem, as their half-life is 1600 years. We are investigating the reduction of radium by transmutation on a small scale by bombarding Ra-226 with high-energy photons from a medical linear accelerator (linac) to produce Ra-225, which subsequently decays to Ac-225, which can be used as a generator to produce Bi-213 for use in 'targeted alpha therapy' for cancer. This paper examines the possibility of producing Ac-225 with a linac using an accurate theoretical model in which the bremsstrahlung photon spectrum at 18 MV linac electron energy is convoluted with the corresponding photonuclear cross sections of Ra-226. The total integrated yield can then be obtained and is compared with a computer simulation. This study shows that at 18 MV, the photonuclear reaction on Ra-226 can produce low activities of Ac-225 with a linac. However, a high power linac with high current, pulse length and frequency is needed to produce practical amounts of Ac-225 and a useful reduction of Ra-226.

Effect of titanium dental implants on proton therapy delivered for head tumors: experimental validation using an anthropomorphic head phantom

NASA Astrophysics Data System (ADS)

Oancea, C.; Shipulin, K.; Mytsin, G.; Molokanov, A.; Niculae, D.; Ambrožová, I.; Davídková, M.

2017-03-01

A dosimetric experiment was performed at the Medico-Technical Complex in the Joint Institute for Nuclear Research, Dubna, to investigate the effects of metallic dental implants in the treatment of head and neck tumours with proton therapy. The goal of the study was to evaluate the 2D dose distributions of different clinical treatment plans measured in an anthropomorphic phantom, and compare them to predictions from a treatment planning system. The anthropomorphic phantom was sliced into horizontal segments. Two grade 4 Titanium implants were inserted between 2 slices, corresponding to a maxillary area. GafChromic EBT2 films were placed between the segments containing the implants to measure the 2D delivered dose. Two different targets were designed: the first target includes the dental implants in the isocentre, and in the second target, the proton beam is delivered through the implants, which are located at the entrance region of the Bragg curve. The experimental results were compared to the treatment plans made using our custom 3D Treatment Planning System, named RayTreat. To quantitatively determine differences in the isodose distributions (measured and calculated), the gamma index (3 mm, 3%) was calculated for each target for the matrix value in the region of high isodose (> 90%): for the experimental setup, which includes the implants in the SOBP region, the result obtained was 84.3%. When the implants were localised in the entrance region of the Bragg curve, the result obtained was 86.4%. In conclusion, the uncertainties introduced by the clinically planned dose distribution are beyond reasonable limits. The linear energy transfer spectra in close proximity to the implants were investigated using solid state nuclear track detectors (TED). Scattered particles outside the target were detected.

FISPACT-II: An Advanced Simulation System for Activation, Transmutation and Material Modelling

NASA Astrophysics Data System (ADS)

Sublet, J.-Ch.; Eastwood, J. W.; Morgan, J. G.; Gilbert, M. R.; Fleming, M.; Arter, W.

2017-01-01

Fispact-II is a code system and library database for modelling activation-transmutation processes, depletion-burn-up, time dependent inventory and radiation damage source terms caused by nuclear reactions and decays. The Fispact-II code, written in object-style Fortran, follows the evolution of material irradiated by neutrons, alphas, gammas, protons, or deuterons, and provides a wide range of derived radiological output quantities to satisfy most needs for nuclear applications. It can be used with any ENDF-compliant group library data for nuclear reactions, particle-induced and spontaneous fission yields, and radioactive decay (including but not limited to TENDL-2015, ENDF/B-VII.1, JEFF-3.2, JENDL-4.0u, CENDL-3.1 processed into fine-group-structure files, GEFY-5.2 and UKDD-16), as well as resolved and unresolved resonance range probability tables for self-shielding corrections and updated radiological hazard indices. The code has many novel features including: extension of the energy range up to 1 GeV; additional neutron physics including self-shielding effects, temperature dependence, thin and thick target yields; pathway analysis; and sensitivity and uncertainty quantification and propagation using full covariance data. The latest ENDF libraries such as TENDL encompass thousands of target isotopes. Nuclear data libraries for Fispact-II are prepared from these using processing codes PREPRO, NJOY and CALENDF. These data include resonance parameters, cross sections with covariances, probability tables in the resonance ranges, PKA spectra, kerma, dpa, gas and radionuclide production and energy-dependent fission yields, supplemented with all 27 decay types. All such data for the five most important incident particles are provided in evaluated data tables. The Fispact-II simulation software is described in detail in this paper, together with the nuclear data libraries. The Fispact-II system also includes several utility programs for code-use optimisation

Spallation reaction study for the long-lived fission product 107Pd

NASA Astrophysics Data System (ADS)

Wang, He; Otsu, Hideaki; Sakurai, Hiroyoshi; Ahn, DeukSoon; Aikawa, Masayuki; Ando, Takashi; Araki, Shouhei; Chen, Sidong; Nobuyuki, Chiga; Doornenbal, Pieter; Fukuda, Naoki; Isobe, Tadaaki; Kawakami, Shunsuke; Kawase, Shoichiro; Kin, Tadahiro; Kondo, Yosuke; Koyama, Shunpei; Kubono, Shigeru; Maeda, Yukie; Makinaga, Ayano; Matsushita, Masafumi; Matsuzaki, Teiichiro; Michimasa, Shin'ichiro; Momiyama, Satoru; Nagamine, Shunsuke; Nakamura, Takashi; Nakano, Keita; Niikura, Megumi; Ozaki, Tomoyuki; Saito, Atsumi; Saito, Takeshi; Shiga, Yoshiaki; Shikata, Mizuki; Shimizu, Yohei; Shimoura, Susumu; Sumikama, Toshiyuki; Söderström, Pär-Anders; Suzuki, Hiroshi; Takeda, Hiroyuki; Takeuchi, Satoshi; Taniuchi, Ryo; Togano, Yasuhiro; Tsubota, Junichi; Uesaka, Meiko; Watanabe, Yasushi; Watanabe, Yukinobu; Wimmer, Kathrin; Yamamoto, Tatsuya; Yoshida, Koichi

2017-02-01

Spallation reactions for the long-lived fission product 107Pd have been studied for the purpose of nuclear waste transmutation. The cross sections on the proton- and deuteron-induced spallation were obtained at 196 and 118 MeV/nucleon in inverse kinematics at the RIKEN Radioactive Isotope Beam Factory. Both the target and energy dependences of cross sections have been investigated systematically. It was found that the proton-induced cross sections at 196 MeV/nucleon are close to those for deuteron obtained at 118 MeV/nucleon for the light-mass products. The experimental data are compared with the SPACS semi-empirical parameterization and the PHITS calculations including both the intranuclear cascade and evaporation processes. Our data give a design goal of proton/deuteron flux for the transmutation of 107Pd using the spallation reaction. In addition, it is found that the spallation reaction at 118 MeV/nucleon may have an advantage over the 107Pd transmutation because of the low production of other long-lived radioactive isotopes.

Proposal of a neutron transmutation doping facility for n-type spherical silicon solar cell at high-temperature engineering test reactor.

PubMed

Ho, Hai Quan; Honda, Yuki; Motoyama, Mizuki; Hamamoto, Shimpei; Ishii, Toshiaki; Ishitsuka, Etsuo

2018-05-01

The p-type spherical silicon solar cell is a candidate for future solar energy with low fabrication cost, however, its conversion efficiency is only about 10%. The conversion efficiency of a silicon solar cell can be increased by using n-type silicon semiconductor as a substrate. This study proposed a new method of neutron transmutation doping silicon (NTD-Si) for producing the n-type spherical solar cell, in which the Si-particles are irradiated directly instead of the cylinder Si-ingot as in the conventional NTD-Si. By using a 'screw', an identical resistivity could be achieved for the Si-particles without a complicated procedure as in the NTD with Si-ingot. Also, the reactivity and neutron flux swing could be kept to a minimum because of the continuous irradiation of the Si-particles. A high temperature engineering test reactor (HTTR), which is located in Japan, was used as a reference reactor in this study. Neutronic calculations showed that the HTTR has a capability to produce about 40t/EFPY of 10Ωcm resistivity Si-particles for fabrication of the n-type spherical solar cell. Copyright © 2018 Elsevier Ltd. All rights reserved.

Thermodynamic and Kinetic Properties of Intrinsic Defects and Mg Transmutants in 3C-SiC Determined by Density Functional Theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Shenyang Y.; Setyawan, Wahyu; Van Ginhoven, Renee M.

2014-02-20

Density functional theory (DFT) is used to calculate the thermodynamic and kinetic properties of transmutant Mg in 3C-SiC due to high-energy neutron irradiation associated with the fusion nuclear environment. The formation and binding energies of intrinsic defects, Mg-related defects, and clusters in 3C-SiC are systematically calculated. The minimum energy paths and activation energies during point defect migration and small cluster evolution are studied using a generalized solid-state elastic band (G-SSNEB) method with DFT energy calculations. Stable defect structures and possible defect migration mechanisms are identified. The evolution of binding energies during Mg2Si formation demonstrates that the formation of Mg2Si needsmore » to overcome a critical nucleus size and nucleation barrier. It is also found that a compressive stress field exists around the Mg2Si nucleus. These data are important inputs in meso- and macro-scale modeling and experiments to understand and predict the impact of Mg on phase stability, microstructure evolution, and performance of SiC and SiC-based materials during long-term neutron exposures.« less

The SANS facility at the Pitesti 14MW TRIGA reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ionita, I.; Grabcev, B.; Todireanu, S.

2006-12-15

The SANS facility existing at the Pitesti 14MW TRIGA reactor is presented. The main characteristics and the preliminary evaluation of the installation performances are given. A monochromatic neutron beam with 1.5 A {<=} {lambda} {<=} 5 A is produced by a mechanical velocity selector with helical slots. A fruitful partnership was established between INR Pitesti (Romania) and JINR Dubna (Russia). The first step in this cooperation consists in the manufacturing in Dubna of a battery of gas-filled positional detectors devoted to the SANS instrument.

Contributions to the mini-workshop on beam-beam compensation in the Tevatron

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shiltsev, V.

1998-02-01

The purpose of the Workshop was to assay the current understanding of compensation of the beam-beam effects in the Tevatron with use of low-energy high-current electron beam, relevant accelerator technology, along with other novel techniques of the compensation and previous attempts. About 30 scientists representing seven institutions from four countries--FNAL, SLAC, BNL, Novosibirsk, CERN, and Dubna were in attendance. Twenty one talks were presented. The event gave firm ground for wider collaboration on experimental test of the compensation at the Tevatron collider. This report consists of vugraphs of talks given at the meeting.

Current experiments in elementary particle physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wohl, C.G.; Armstrong, F.E.; Trippe, T.G.

1989-09-01

This report contains summaries of 736 current and recent experiments in elementary particle physics (experiments that finished taking data before 1982 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Tokyo Institute of Nuclear Studies, Moscow Institute of Theoretical and Experimental Physics, Joint Institute for Nuclear Research (Dubna), KEK, LAMPF, Novosibirsk, PSI/SIN, Saclay, Serpukhov, SLAC, and TRIUMF, and also several underground experiments. Also given are instructions for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries. Properties of the fixed-target beams at most of the laboratories are summarized.

Spallation reaction study for fission products in nuclear waste: Cross section measurements for 137Cs and 90Sr on proton and deuteron

NASA Astrophysics Data System (ADS)

Wang, H.; Otsu, H.; Sakurai, H.; Ahn, D. S.; Aikawa, M.; Doornenbal, P.; Fukuda, N.; Isobe, T.; Kawakami, S.; Koyama, S.; Kubo, T.; Kubono, S.; Lorusso, G.; Maeda, Y.; Makinaga, A.; Momiyama, S.; Nakano, K.; Niikura, M.; Shiga, Y.; Söderström, P.-A.; Suzuki, H.; Takeda, H.; Takeuchi, S.; Taniuchi, R.; Watanabe, Ya.; Watanabe, Yu.; Yamasaki, H.; Yoshida, K.

2016-03-01

We have studied spallation reactions for the fission products 137Cs and 90Sr for the purpose of nuclear waste transmutation. The spallation cross sections on the proton and deuteron were obtained in inverse kinematics for the first time using secondary beams of 137Cs and 90Sr at 185 MeV/nucleon at the RIKEN Radioactive Isotope Beam Factory. The target dependence has been investigated systematically, and the cross-section differences between the proton and deuteron are found to be larger for lighter spallation products. The experimental data are compared with the PHITS calculation, which includes cascade and evaporation processes. Our results suggest that both proton- and deuteron-induced spallation reactions are promising mechanisms for the transmutation of radioactive fission products.

Exactly soluble local bosonic cocycle models, statistical transmutation, and simplest time-reversal symmetric topological orders in 3+1 dimensions

NASA Astrophysics Data System (ADS)

Wen, Xiao-Gang

2017-05-01

We propose a generic construction of exactly soluble local bosonic models that realize various topological orders with gappable boundaries. In particular, we construct an exactly soluble bosonic model that realizes a (3+1)-dimensional [(3+1)D] Z2-gauge theory with emergent fermionic Kramers doublet. We show that the emergence of such a fermion will cause the nucleation of certain topological excitations in space-time without pin+ structure. The exactly soluble model also leads to a statistical transmutation in (3+1)D. In addition, we construct exactly soluble bosonic models that realize 2 types of time-reversal symmetry-enriched Z2 topological orders in 2+1 dimensions, and 20 types of simplest time-reversal symmetry-enriched topological (SET) orders which have only one nontrivial pointlike and stringlike topological excitation. Many physical properties of those topological states are calculated using the exactly soluble models. We find that some time-reversal SET orders have pointlike excitations that carry Kramers doublet, a fractionalized time-reversal symmetry. We also find that some Z2 SET orders have stringlike excitations that carry anomalous (nononsite) Z2 symmetry, which can be viewed as a fractionalization of Z2 symmetry on strings. Our construction is based on cochains and cocycles in algebraic topology, which is very versatile. In principle, it can also realize emergent topological field theory beyond the twisted gauge theory.

Study of residual stresses in CT test specimens welded by electron beam

NASA Astrophysics Data System (ADS)

Papushkin, I. V.; Kaisheva, D.; Bokuchava, G. D.; Angelov, V.; Petrov, P.

2018-03-01

The paper reports result of residual stress distribution studies in CT specimens reconstituted by electron beam welding (EBW). The main aim of the study is evaluation of the applicability of the welding technique for CT specimens’ reconstitution. Thus, the temperature distribution during electron beam welding of a CT specimen was calculated using Green’s functions and the residual stress distribution was determined experimentally using neutron diffraction. Time-of-flight neutron diffraction experiments were performed on a Fourier stress diffractometer at the IBR-2 fast pulsed reactor in FLNP JINR (Dubna, Russia). The neutron diffraction data estimates yielded a maximal stress level of ±180 MPa in the welded joint.

Connecting the "Hot Fusion Island" to the Nuclear Mainland: Search for 283,284,285Fl Decay Chains

NASA Astrophysics Data System (ADS)

Rykaczewski, K. P.; Utyonkov, V. K.; Brewer, N. T.; Grzywacz, R. K.; Miernik, K.; Roberto, J. B.; Oganessian, Yu. Ts.; Polyakov, A. N.; Tsyganov, Yu. S.; Voinov, A. A.; Abdullin, F. Sh.; Dmitriev, S. N.; Itkis, M. G.; Sabelnikov, A. V.; Sagaidak, R. N.; Shirokovsky, I. V.; Shumeiko, M. V.; Subbotin, V. G.; Sukhov, A. M.; Vostokin, G. K.; Hamilton, J. H.; Henderson, R. A.; Stoyer, M. A.

The program of studies on superheavy nuclei to identify new isotopes anchoring the decay chains from the Hot Fusion Island to the Nuclear Mainland has been started at the Dubna Gas Filled Recoil Separator (DGFRS, JINR Dubna) in collaboration between Russia, US and Poland. These studies are performed with new detection and digital data acquisition system developed at ORNL (Oak Ridge) and UT (Knoxville). The evidence for fast fission of the new isotope 284Fl is presented. The low cross section for the 3n channel of 239Pu + 48Ca reaction is attributed to lower than expected fission barriers in 287-284Fl.

Friction Stir Welding of HT9 Ferritic-Martensitic Steel: An Assessment of Microstructure and Properties

DTIC Science & Technology

2013-06-01

X, where X represents lithium, sodium, beryllium, or transmutation products, such as tritium [47]. In this mechanism, the transmutation of lithium...Similar to the study by Williams, Farmer found that galvanic coupling, increased temperature and the formation of transmutation products (HF and TF), a

Effect of Vacuum Properties on Electroweak Processes - A Theoretical Interpretation of Experiments

NASA Astrophysics Data System (ADS)

Stumpf, Harald

2008-06-01

Recently for discharges in fluids induced nuclear transmutations have been observed. It is our hypothesis that these reactions are due to a symmetry breaking of the electroweak vacuum by the experimental arrangement. The treatment of this hypothesis is based on the assumption that electroweak bosons, leptons and quarks possess a substructure of elementary fermionic constituents. The dynamical law of these fermionic constituents is given by a relativistically invariant nonlinear spinor field equation with local interaction, canonical quantization, selfregularization and probability interpretation. Phenomenological quantities of electroweak processes follow from the derivation of corresponding effective theories obtained by algebraic weak mapping theorems where the latter theories depend on the spinor field propagator, i. e. a vacuum expectation value. This propagator and its equation are studied for conserved and for broken discrete symmetries. For combined CP- and isospin symmetry breaking it is shown that the propagator corresponds to the experimental arrangements under consideration. The modifications of the effective electroweak theory due to this modified propagator are discussed. Based on these results a mechanism is sketched which offers a qualitative interpretation of the appearance of induced nuclear transmutations. A numerical estimate of electron capture is given.

U-238 fission and Pu-239 production in subcritical assembly

NASA Astrophysics Data System (ADS)

Grab, Magdalena; Wojciechowski, Andrzej

2018-04-01

The project touches upon an issue of U-238 fission reactions and Pu-239 production reactions in subcritical assembly. The experiment took place in November 2014 at the Dzhelepov Laboratory of Nuclear Problems (JINR, Dubna) using PHASOTRON.Data of this experiment were analyzed in Laboratory of Information Technologies (LIT). Four MCNPX models were considered for simulation: Bertini/Dresnen, Bertini/Abla, INCL4/Drensnen, INCL4/Abla. The main goal of the project was to compare the experimental data and simulation results. We obtain a good agreement of experimental data and computation results especially for detectors placed besides the assembly axis. In addition, the U-238 fission reactions are more probable to be observed in the region of a higher particle energy spectrum, located closer to the assembly axis and the particle beam as well and vice versa Pu-239 production reactions were dominant in the peripheral region of geometry.

Coherent transmutation of electrons into fractionalized anyons.

PubMed

Barkeshli, Maissam; Berg, Erez; Kivelson, Steven

2014-11-07

Electrons have three quantized properties-charge, spin, and Fermi statistics-that are directly responsible for a vast array of phenomena. Here we show how these properties can be coherently and dynamically stripped from the electron as it enters a certain exotic state of matter known as a quantum spin liquid (QSL). In a QSL, electron spins collectively form a highly entangled quantum state that gives rise to the fractionalization of spin, charge, and statistics. We show that certain QSLs host distinct, topologically robust boundary types, some of which allow the electron to coherently enter the QSL as a fractionalized quasi-particle, leaving its spin, charge, or statistics behind. We use these ideas to propose a number of universal, conclusive experimental signatures that would establish fractionalization in QSLs. Copyright © 2014, American Association for the Advancement of Science.

Remembering Yakov Abramovich

NASA Astrophysics Data System (ADS)

Frenkel, A.

2013-06-01

Shortly after its foundation in 1956 the Joint Institute for Nuclear Research in Dubna became an important training place for young physicists from Eastern-European countries. In those years I, too, was much younger than now, and from the late 1950s until the mid-1980s visited the Laboratory of Theoretical Physics many times for a few weeks. Discussions with Yakov Abramovich about particle physics and field theory were always interesting and instructive. When flavor SU(3) symmetry was discovered, his Dubna reprint review on the subject for me - and I think not only for me - proved to be a very helpful handbook during many subsequent years. Let me also tell you about an episode which I remember with gratitude...

Modeling Radioactive Decay Chains with Branching Fraction Uncertainties

DTIC Science & Technology

2013-03-01

moments methods with transmutation matrices. Uncertainty from both half-lives and branching fractions is carried through these calculations by Monte...moment methods, method for sampling from normal distributions for half- life uncertainty, and use of transmutation matrices were leveraged. This...distributions for half-life and branching fraction uncertainties, building decay chains and generating the transmutation matrix (T-matrix

Unifying relations for scattering amplitudes

NASA Astrophysics Data System (ADS)

Cheung, Clifford; Shen, Chia-Hsien; Wen, Congkao

2018-02-01

We derive new amplitudes relations revealing a hidden unity among a wideranging variety of theories in arbitrary spacetime dimensions. Our results rely on a set of Lorentz invariant differential operators which transmute physical tree-level scattering amplitudes into new ones. By transmuting the amplitudes of gravity coupled to a dilaton and two-form, we generate all the amplitudes of Einstein-Yang-Mills theory, Dirac-Born-Infield theory, special Galileon, nonlinear sigma model, and biadjoint scalar theory. Transmutation also relates amplitudes in string theory and its variants. As a corollary, celebrated aspects of gluon and graviton scattering like color-kinematics duality, the KLT relations, and the CHY construction are inherited traits of the transmuted amplitudes. Transmutation recasts the Adler zero as a trivial consequence of the Weinberg soft theorem and implies new subleading soft theorems for certain scalar theories.

Yields of projectile fragments in sulphur-emulsion interactions at 3.7 A GeV

NASA Astrophysics Data System (ADS)

Kamel, S.; Osman, W.; Fayed, M.

2017-05-01

This work presents the basic characteristics of singly, doubly and heavily charged projectile fragments (PFs) emitted in inelastic interactions of 32S ions with photo-emulsion nuclei at Dubna energy (3.7 A GeV). Our experimental data are compared with the corresponding data for other projectiles at the same incident energy. The study of mean multiplicities of different charged PFs against the projectile mass shows a power-law relationship. The multiplicity distributions of singly and doubly charged PFs have been fitted well with a Gaussian distribution function. The yields of PFs broken up from the interactions of 32S projectile nuclei with different target nuclei are studied. The beam energy dependence in terms of the various order moments is studied as well.

Experimental study of the electric dipole strength in the even Mo nuclei and its deformation dependence

NASA Astrophysics Data System (ADS)

Erhard, M.; Junghans, A. R.; Nair, C.; Schwengner, R.; Beyer, R.; Klug, J.; Kosev, K.; Wagner, A.; Grosse, E.

2010-03-01

Two methods based on bremsstrahlung were applied to the stable even Mo isotopes for the experimental determination of the photon strength function covering the high excitation energy range above 4 MeV with its increasing level density. Photon scattering was used up to the neutron separation energies Sn and data up to the maximum of the isovector giant resonance (GDR) were obtained by photoactivation. After a proper correction for multistep processes the observed quasicontinuous spectra of scattered photons show a remarkably good match to the photon strengths derived from nuclear photoeffect data obtained previously by neutron detection and corrected in absolute scale by using the new activation results. The combined data form an excellent basis to derive a shape dependence of the E1 strength in the even Mo isotopes with increasing deviation from the N=50 neutron shell (i.e., with the impact of quadrupole deformation and triaxiality). The wide energy coverage of the data allows for a stringent assessment of the dipole sum rule and a test of a novel parametrization developed previously which is based on it. This parametrization for the electric dipole strength function in nuclei with A>80 deviates significantly from prescriptions generally used previously. In astrophysical network calculations it may help to quantify the role the p-process plays in cosmic nucleosynthesis. It also has impact on the accurate analysis of neutron capture data of importance for future nuclear energy systems and waste transmutation.

Determination of the nuclear level densities and radiative strength function for 43 nuclei in the mass interval 28≤A≤200

NASA Astrophysics Data System (ADS)

Knezevic, David; Jovancevic, Nikola; Sukhovoj, Anatoly M.; Mitsyna, Ludmila V.; Krmar, Miodrag; Cong, Vu D.; Hambsch, Franz-Josef; Oberstedt, Stephan; Revay, Zsolt; Stieghorst, Christian; Dragic, Aleksandar

2018-03-01

The determination of nuclear level densities and radiative strength functions is one of the most important tasks in low-energy nuclear physics. Accurate experimental values of these parameters are critical for the study of the fundamental properties of nuclear structure. The step-like structure in the dependence of the level densities p on the excitation energy of nuclei Eex is observed in the two-step gamma cascade measurements for nuclei in the 28 ≤ A ≤ 200 mass region. This characteristic structure can be explained only if a co-existence of quasi-particles and phonons, as well as their interaction in a nucleus, are taken into account in the process of gamma-decay. Here we present a new improvement to the Dubna practical model for the determination of nuclear level densities and radiative strength functions. The new practical model guarantees a good description of the available intensities of the two step gamma cascades, comparable to the experimental data accuracy.

Study of 232Th(n, γ) and 232Th(n,f) reaction rates in a graphite moderated spallation neutron field produced by 1.6 GeV deuterons on lead target

NASA Astrophysics Data System (ADS)

Asquith, N. L.; Hashemi-Nezhad, S. R.; Westmeier, W.; Zhuk, I.; Tyutyunnikov, S.; Adam, J.

2015-02-01

The Gamma-3 assembly of the Joint Institute for Nuclear Research (JINR), Dubna, Russia is designed to emulate the neutron spectrum of a thermal Accelerator Driven System (ADS). It consists of a lead spallation target surrounded by reactor grade graphite. The target was irradiated with 1.6 GeV deuterons from the Nuclotron accelerator and the neutron capture and fission rate of 232Th in several locations within the assembly were experimentally measured. 232Th is a proposed fuel for envisaged Accelerator Driven Systems and these two reactions are fundamental to the performance and feasibility of 232Th in an ADS. The irradiation of the Gamma-3 assembly was also simulated using MCNPX 2.7 with the INCL4 intra-nuclear cascade and ABLA fission/evaporation models. Good agreement between the experimentally measured and calculated reaction rates was found. This serves as a good validation for the computational models and cross section data used to simulate neutron production and transport of spallation neutrons within a thermal ADS.

Characterization of Neutron-Induced Defects in Isotopically Enriched Lithium Tetraborate

DTIC Science & Technology

2011-03-01

that efficiently captures and transmutes neutrons into more readily detected forms of material or energy. Neutron detection is desirable to detect...be used to transmute neutrons into a more readily detectable particle or energy. Upon absorbing a thermal neutron, 6Li undergoes the reaction, 6 1...both 6Li and 10B in natural abundances unless deliberately enriched. In addition to the direct reactions, 6Li or 7Li and 16O can transmute neutrons

Ab initio calculations of mechanical properties of bcc W-Re-Os random alloys: effects of transmutation of W

NASA Astrophysics Data System (ADS)

Li, Xiaojie; Schönecker, Stephan; Li, Ruihuan; Li, Xiaoqing; Wang, Yuanyuan; Zhao, Jijun; Johansson, Börje; Vitos, Levente

2016-07-01

To examine the effect of neutron transmutation on tungsten as the first wall material of fusion reactors, the elastic properties of W1-x-y  Re x  Os y (0  ⩽  x, y  ⩽  6%) random alloys in body centered cubic (bcc) structure are investigated systematically using the all-electron exact muffin-tin orbitals (EMTO) method in combination with the coherent-potential approximation (CPA). The calculated lattice constant and elastic properties of pure W are consistent with available experiments. Both Os and Re additions reduce the lattice constant and increase the bulk modulus of W, with Os having the stronger effect. The polycrystalline shear modulus, Young’s modulus and the Debye temperature increase (decrease) with the addition of Re (Os). Except for C 11, the other elastic parameters including C 12, C 44, Cauchy pressure, Poisson ratio, B/G, increase as a function of Re and Os concentration. The variations of the latter three parameters and the trend in the ratio of cleavage energy to shear modulus for the most dominant slip system indicate that the ductility of the alloy enhances with increasing Re and Os content. The calculated elastic anisotropy of bcc W slightly increases with the concentration of both alloying elements. The estimated melting temperatures of the W-Re-Os alloy suggest that Re or Os addition will reduce the melting temperature of pure W solid. The classical Labusch-Nabarro model for solid-solution hardening predicts larger strengthening effects in W1-y  Os y than in W1-x  Re x . A strong correlation between C‧ and the fcc-bcc structural energy difference for W1-x-y  Re x  Os y is revealed demonstrating that canonical band structure dictates the alloying effect on C‧. The structural energy difference is exploited to estimate the alloying effect on the ideal tensile strength in the [0 0 1] direction.

Ab initio calculations of mechanical properties of bcc W-Re-Os random alloys: effects of transmutation of W.

PubMed

Li, Xiaojie; Schönecker, Stephan; Li, Ruihuan; Li, Xiaoqing; Wang, Yuanyuan; Zhao, Jijun; Johansson, Börje; Vitos, Levente

2016-06-03

To examine the effect of neutron transmutation on tungsten as the first wall material of fusion reactors, the elastic properties of W 1-x-y  Re x  Os y (0  ⩽  x, y  ⩽  6%) random alloys in body centered cubic (bcc) structure are investigated systematically using the all-electron exact muffin-tin orbitals (EMTO) method in combination with the coherent-potential approximation (CPA). The calculated lattice constant and elastic properties of pure W are consistent with available experiments. Both Os and Re additions reduce the lattice constant and increase the bulk modulus of W, with Os having the stronger effect. The polycrystalline shear modulus, Young's modulus and the Debye temperature increase (decrease) with the addition of Re (Os). Except for C 11 , the other elastic parameters including C 12 , C 44 , Cauchy pressure, Poisson ratio, B/G, increase as a function of Re and Os concentration. The variations of the latter three parameters and the trend in the ratio of cleavage energy to shear modulus for the most dominant slip system indicate that the ductility of the alloy enhances with increasing Re and Os content. The calculated elastic anisotropy of bcc W slightly increases with the concentration of both alloying elements. The estimated melting temperatures of the W-Re-Os alloy suggest that Re or Os addition will reduce the melting temperature of pure W solid. The classical Labusch-Nabarro model for solid-solution hardening predicts larger strengthening effects in W 1-y  Os y than in W 1-x  Re x . A strong correlation between C' and the fcc-bcc structural energy difference for W 1-x-y  Re x  Os y is revealed demonstrating that canonical band structure dictates the alloying effect on C'. The structural energy difference is exploited to estimate the alloying effect on the ideal tensile strength in the [0 0 1] direction.

Heaviest Nuclei: New Element with Atomic Number 117

ScienceCinema

Oganessian, Yuri

2018-01-24

One of the fundamental outcomes of the nuclear shell model is the prediction of the 'stability islands' in the domain of the hypothetical super heavy elements. The talk is devoted to the experimental verification of these predictions - the synthesis and study of both the decay and chemical properties of the super heavy elements. The discovery of a new chemical element with atomic number Z=117 is reported. The isotopes 293117 and 294117 were produced in fusion reactions between 48Ca and 249Bk. Decay chains involving 11 new nuclei were identified by means of the Dubna gas-filled recoil separator. The measured decay properties show a strong rise of stability for heavier isotopes with Z =111, validating the concept of the long sought island of enhanced stability for heaviest nuclei.

The End of Alchemy? The Repudiation and Persistence of Chrysopoeia at the Académie Royale des Sciences in the Eighteenth Century.

PubMed

Principe, Lawrence M

2014-01-01

The general abandonment of serious endeavor toward metallic transmutation represents a major development in the history of chemistry, yet its exact causes and timing remain unclear. This essay examines the fate of chrysopoeia at the eighteenth-century Académie Royale des Sciences. It reveals a long-standing tension between Académie chemists, who pursued transmutation, and administrators, who tried to suppress it. This tension provides background for Etienne-François Geoffroy's 1722 paper describing fraudulent practices around transmutation. Although transmutation seems to disappear after Geoffroy's paper, manuscripts reveal that most of the institution's chemists continued to pursue it privately until at least the 1760s, long after widely accepted dates for the "demise of alchemy" in learned circles.

The Soviet Central Asian Challenge: A Neo-Gramscian Analysis.

DTIC Science & Technology

1986-09-01

transmutated into the Soviet Union. This point is fundamental to understanding why the Russians are the ruling nationality group in the Soviet Union. The Great...initial years, force and coercion were instrumental for ensuring the continued existence of the transmuted Russian Empire. The new Soviet Union also...information on .Muslim national communism s1 l (Reft. 31, i33. 26F1or an excellent article on Russian nationalism’s transmutation to Soviet communism and the

Experimental studies of the medical radioisotopes production in neutron spectra generated by 660 MeV protons and 1-8 GeV deuterons in massive uranium target

NASA Astrophysics Data System (ADS)

Zhadan, A.; Sotnikov, V.; Adam, J.; Solnyshkin, A.; Tyutyunnikov, S.; Voronko, V.; Zhivkov, P.; Zavorka, L.

2017-06-01

The possibility of medical radionuclide 64,67Cu production in spallation neutron spectrum induced by proton and deuteron beams has been studied. Experiments were performed on a massive natural uranium target at the accelerators Phasotron and Nuclotron JINR, Dubna. The main disadvantage of this method is a high 64Cu/67Cu ratio in the final product at EOB. Significantly reduce 64Cu/67Cu ratio is only possible if you use zinc target enriched with 68Zn or 67Zn. The MCNPX simulation of 67,64Cu production and definition of the theoretical limit of the specific activity of 67,64Cu by irradiation of natural zinc and zinc enriched by the 68 isotope were performed. The neutron flux density shouldnot be less than 5.1013 n/cm2/s if we want to obtain high specific activity (>200 GBq/mg) of 67Cu.

Next generation fuel irradiation capability in the High Flux Reactor Petten

NASA Astrophysics Data System (ADS)

Fütterer, Michael A.; D'Agata, Elio; Laurie, Mathias; Marmier, Alain; Scaffidi-Argentina, Francesco; Raison, Philippe; Bakker, Klaas; de Groot, Sander; Klaassen, Frodo

2009-07-01

This paper describes selected equipment and expertise on fuel irradiation testing at the High Flux Reactor (HFR) in Petten, The Netherlands. The reactor went critical in 1961 and holds an operating license up to at least 2015. While HFR has initially focused on Light Water Reactor fuel and materials, it also played a decisive role since the 1970s in the German High Temperature Reactor (HTR) development program. A variety of tests related to fast reactor development in Europe were carried out for next generation fuel and materials, in particular for Very High Temperature Reactor (V/HTR) fuel, fuel for closed fuel cycles (U-Pu and Th-U fuel cycle) and transmutation, as well as for other innovative fuel types. The HFR constitutes a significant European infrastructure tool for the development of next generation reactors. Experimental facilities addressed include V/HTR fuel tests, a coated particle irradiation rig, and tests on fast reactor, transmutation and thorium fuel. The rationales for these tests are given, results are provided and further work is outlined.

Validation of Monte Carlo simulation of neutron production in a spallation experiment

DOE PAGES

Zavorka, L.; Adam, J.; Artiushenko, M.; ...

2015-02-25

A renewed interest in experimental research on Accelerator-Driven Systems (ADS) has been initiated by the global attempt to produce energy from thorium as a safe(r), clean(er) and (more) proliferation-resistant alternative to the uranium-fuelled thermal nuclear reactors. The ADS research has been actively pursued at the Joint Institute for Nuclear Research (JINR), Dubna, since decades. Most recently, the emission of fast neutrons was experimentally investigated at the massive (m = 512 kg) natural uranium spallation target QUINTA. The target has been irradiated with the relativistic deuteron beams of energy from 0.5 AGeV up to 4 AGeV at the JINR Nuclotron acceleratormore » in numerous experiments since 2011. Neutron production inside the target was studied through the gamma-ray spectrometry measurement of natural uranium activation detectors. Experimental reaction rates for (n,γ), (n,f) and (n,2n) reactions in uranium have provided valuable information about the neutron distribution over a wide range of energies up to some GeV. The experimental data were compared to the predictions of Monte Carlo simulations using the MCNPX 2.7.0 code. In conclusion, the results are presented and potential sources of partial disagreement are discussed later in this work.« less

High Intensity Proton Accelerator Project in Japan (J-PARC).

PubMed

Tanaka, Shun-ichi

2005-01-01

The High Intensity Proton Accelerator Project, named as J-PARC, was started on 1 April 2001 at Tokai-site of JAERI. The accelerator complex of J-PARC consists of three accelerators: 400 MeV Linac, 3 GeV rapid cycle synchrotron and 50 GeV synchrotron; and four major experimental facilities: Material and Life Science Facility, Nuclear and Particle Physics Facility, Nuclear Transmutation Experiment Facility and Neutrino Facility. The outline of the J-PARC is presented with the current status of construction.

Systematic study of rapidity dispersion parameter in high energy nucleus-nucleus interactions

NASA Astrophysics Data System (ADS)

Bhattacharyya, Swarnapratim; Haiduc, Maria; Neagu, Alina Tania; Firu, Elena

2014-03-01

A systematic study of rapidity dispersion parameter as a quantitative measure of clustering of particles has been carried out in the interactions of 16O, 28Si and 32S projectiles at 4.5 A GeV/c with heavy (AgBr) and light (CNO) groups of targets present in the nuclear emulsion. For all the interactions, the total ensemble of events has been divided into four overlapping multiplicity classes depending on the number of shower particles. For all the interactions and for each multiplicity class, the rapidity dispersion parameter values indicate the occurrence of clusterization during the multiparticle production at Dubna energy. The measured rapidity dispersion parameter values are found to decrease with the increase of average multiplicity for all the interactions. The dependence of rapidity dispersion parameter on the average multiplicity can be successfully described by a relation D(η) = a + b + c2. The experimental results have been compared with the results obtained from the analysis of Monte Carlo simulated (MC-RAND) events. MC-RAND events show weaker clusterization among the pions in comparison to the experimental data.

Actinide management with commercial fast reactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ohki, Shigeo

The capability of plutonium-breeding and minor-actinide (MA) transmutation in the Japanese commercial sodium-cooled fast reactor offers one of practical solutions for obtaining sustainable energy resources as well as reducing radioactive toxicity and inventory. The reference core design meets the requirement of flexible breeding ratio from 1.03 to 1.2. The MA transmutation amount has been evaluated as 50-100 kg/GW{sub e}y if the MA content in fresh fuel is 3-5 wt%, where about 30-40% of initial MA can be transmuted in the discharged fuel.

Application of the mass-spectrometer MASHA for mass-spectrometry and laser-spectroscopy

NASA Astrophysics Data System (ADS)

Rodin, A. M.; Belozerov, A. V.; Dmitriev, S. N.; Oganessian, Yu. Ts.; Sagaidak, R. N.; Salamatin, V. S.; Stepantsov, S. V.; Vanin, D. V.

2010-02-01

We report the present status of the mass-spectrometer MASHA (Mass-Analyzer of Supper Heavy Atoms) designed for determination of the masses of superheavy elements. The mass-spectrometer is connected to the U-400M cyclotron of the Flerov Laboratory for Nuclear Reactions (FLNR) JINR, Dubna. The first experiments on mass-measurements for 112 and 114 elements will be performed in the upcoming 2010. For this purpose a hot catcher, based on a graphite stopper, is constructed. The α-decay of the superheavy nuclides or spontaneous fission products will be detected with a silicon 192 strips detector. The experimental program of future investigations using the technique of a gas catcher is discussed. It should be regarded as an alternative of the classical ISOL technique. The possibilities are considered for using this mass-spectrometer for laser spectroscopy of nuclei far off-stability.

Conjugated Gammadion Chiral Metamaterial with Uniaxial Optical Activity and Negative Refractive Index

DTIC Science & Technology

2011-01-10

in Fig. 4, we discuss a procedure of transmutation from the simple -particle chiral element to the conjugated gammadion chiral metamaterial. The...the transmutation from the simple -particle chiral element to the conjugated gammadion chiral metamaterial. The procedure shows how the magnetic or

Specification-based Error Recovery: Theory, Algorithms, and Usability

DTIC Science & Technology

2013-02-01

transmuting the specification to an implementation at run-time and reducing the performance overhead. A suite of techniques and tools were designed...in the specification, thereby transmuting the specification to an implementation at run-time and reducing the perfor- mance overhead. A suite of

Santa Muerte: Threatening the U.S. Homeland

DTIC Science & Technology

2011-03-08

7 Religious Transmutation ...Religious Transmutation Similarly, a small number of anthropologists do not support the notorious claims about Santa Muerte. They believe that...Muerte, it is no wonder that the religion is spreading globally. Random Terror Slave holding, sexual activity with minors, kidnapping, and

Gas phase chemical studies of superheavy elements using the Dubna gas-filled recoil separator - Stopping range determination

NASA Astrophysics Data System (ADS)

Wittwer, D.; Abdullin, F. Sh.; Aksenov, N. V.; Albin, Yu. V.; Bozhikov, G. A.; Dmitriev, S. N.; Dressler, R.; Eichler, R.; Gäggeler, H. W.; Henderson, R. A.; Hübener, S.; Kenneally, J. M.; Lebedev, V. Ya.; Lobanov, Yu. V.; Moody, K. J.; Oganessian, Yu. Ts.; Petrushkin, O. V.; Polyakov, A. N.; Piguet, D.; Rasmussen, P.; Sagaidak, R. N.; Serov, A.; Shirokovsky, I. V.; Shaughnessy, D. A.; Shishkin, S. V.; Sukhov, A. M.; Stoyer, M. A.; Stoyer, N. J.; Tereshatov, E. E.; Tsyganov, Yu. S.; Utyonkov, V. K.; Vostokin, G. K.; Wegrzecki, M.; Wilk, P. A.

2010-01-01

Currently, gas phase chemistry experiments with heaviest elements are usually performed with the gas-jet technique with the disadvantage that all reaction products are collected in a gas-filled thermalisation chamber adjacent to the target. The incorporation of a physical preseparation device between target and collection chamber opens up the perspective to perform new chemical studies. But this approach requires detailed knowledge of the stopping force (STF) of the heaviest elements in various materials. Measurements of the energy loss of mercury (Hg), radon (Rn), and nobelium (No) in Mylar and argon (Ar) were performed at low kinetic energies of around (40-270) keV per nucleon. The experimentally obtained values were compared with STF calculations of the commonly used program for calculating stopping and ranges of ions in matter (SRIM). Using the obtained data points an extrapolation of the STF up to element 114, eka-lead, in the same stopping media was carried out. These estimations were applied to design and to perform a first chemical experiment with a superheavy element behind a physical preseparator using the nuclear fusion reaction 244Pu( 48Ca; 3n) 289114. One decay chain assigned to an atom of 285112, the α-decay product of 289114, was observed.

The outreach sessions

NASA Astrophysics Data System (ADS)

Trache, Livius

2017-06-01

These are moderator's remarks about the outreach sessions on the Saturday in the middle of the Carpathian Summer School of Physics 2016, on July 2nd, and in particular about the afternoon session in round table format with the subject: "JINR Dubna at 60 and the internationalization of science".

Separations in the STATS report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choppin, G.R.

1996-12-31

The Separations Technology and Transmutation Systems (STATS) Committee formed a Subcommittee on Separations. This subcommittee was charged with evaluating the separations proposed for the several reactor and accelerator transmutation systems. It was also asked to review the processing options for the safe management of high-level waste generated by the defense programs, in particular, the special problems involved in dealing with the waste at the U.S. Department of Energy (DOE) facility in Hanford, Washington. Based on the evaluations from the Subcommittee on Separations, the STATS Committee concluded that for the reactor transmutation programs, aqueous separations involving a combination of PUREX andmore » TRUEX solvent extraction processes could be used. However, additional research and development (R&D) would be required before full plant-scale use of the TRUEX technology could be employed. Alternate separations technology for the reactor transmutation program involves pyroprocessing. This process would require a significant amount of R&D before its full-scale application can be evaluated.« less

Nuclear waste disposal utilizing a gaseous core reactor

NASA Technical Reports Server (NTRS)

Paternoster, R. R.

1975-01-01

The feasibility of a gaseous core nuclear reactor designed to produce power to also reduce the national inventories of long-lived reactor waste products through nuclear transmutation was examined. Neutron-induced transmutation of radioactive wastes is shown to be an effective means of shortening the apparent half life.

The oxygen enhancement ratio for single- and double-strand breaks induced by tritium incorporated in DNA of cultured human T1 cells. Impact of the transmutation effect.

PubMed

Tisljar-Lentulis, G; Henneberg, P; Feinendegen, L E; Commerford, S L

1983-04-01

The effect of oxygen, expressed as the oxygen enhancement ratio (OER), on the number of single-strand breaks (SSB) and double-strand breaks (DSB) induced in DNA by the radioactive decay of tritium was measured in human T1 cells whose DNA had been labeled with tritium at carbon atom number 6 of thymidine. Decays were accumulated in vivo under aerobic conditions at 0-1 degrees C and at -196 degrees C and in a nitrogen atmosphere at 0-1 degrees C. The number of SSB and DSB produced was analyzed by sucrose gradient centrifugation. For each tritium decay there were 0.25 DSB in cells exposed to air at 0-1 degrees C and 0.07 in cells kept under nitrogen, indicating an OER of 3.6, a value expected for such low-LET radiation. However, for each tritium decay there were 1.25 SSB in cells exposed to air at 0-1 degrees C and 0.76 in cells kept under nitrogen indicating an OER of only 1.7. The corresponding values for 60Co gamma radiation, expressed as SSB per 100 eV absorbed energy, were 4.5 and 1.0, giving an OER of 4.5. The low OER value found for SSB induced by tritium decay can be explained if 31% of the total SSB produced in air result from transmutation by a mechanism which does not produce DSB and is unaffected by oxygen.

Experimental and Quasi-Experimental Design.

ERIC Educational Resources Information Center

Cottrell, Edward B.

With an emphasis on the problems of control of extraneous variables and threats to internal and external validity, the arrangement or design of experiments is discussed. The purpose of experimentation in an educational institution, and the principles governing true experimentation (randomization, replication, and control) are presented, as are…

Processes of hypernuclei formation in relativistic ion collisions

NASA Astrophysics Data System (ADS)

Botvina, Alexander; Bleicher, Marcus

2018-02-01

The study of hypernuclei in relativistic ion collisions open new opportunities for nuclear and particle physics. The main processes leading to the production of hypernuclei in these reactions are the disintegration of large excited hyper-residues (target- and projectile-like), and the coalescence of hyperons with other baryons into light clusters. We use the transport, coalescence and statistical models to describe the whole reaction, and demonstrate the effectiveness of this approach: These reactions lead to the abundant production of multi-strange nuclei and new hypernuclear states. A broad distribution of predicted hypernuclei in masses and isospin allows for investigating properties of exotic hypernuclei, as well as the hypermatter both at high and low temperatures. There is a saturation of the hypernuclei production at high energies, therefore, the optimal way to pursue this experimental research is to use the accelerator facilities of intermediate energies, like FAIR (Darmstadt) and NICA (Dubna).

E-36: The First Proto-Megascience Experiment at NAL

NASA Astrophysics Data System (ADS)

Pronskikh, Vitaly S.

2016-12-01

E-36, an experiment on small-angle proton-proton scattering, began testing equipment at the National Accelerator Laboratory (NAL) using a newly achieved 100 GeV proton beam on February 12, 1972, marking the beginning of NAL's experimental program. This experiment, which drew collaborators from NAL, the Joint Institute for Nuclear Research (Dubna, USSR), the University of Rochester (Rochester, New York), and Rockefeller University (New York, New York) was significant not only as a milestone in Fermilab's history but also as a model of cooperation between the East and West at a time when Cold War tensions still ran high. An examination of the origin, operation, and resolution of E-36 and the chain of experiments it spawned reveals the complex interplay of science and politics that drove these experiments as well as seeds of the megascience paradigm that has come to dominate high energy physics research since the 1970s.

Investigation of rail wheel steel crystallographic texture changes due to modification and thermomechanical treatment

NASA Astrophysics Data System (ADS)

Lychagina, T.; Nikolayev, D.; Sanin, A.; Tatarko, J.; Ullemeyer, K.

2015-04-01

In this work crystallographic texture for a set of rail wheel steel samples with different regimes of thermo-mechanical treatment and with and without modification by system Al-Mg-Si- Fe-C-Ca-Ti-Ce was measured by neutron diffraction. The texture measurements were carried out by using time-of-flight technique at SKAT diffractometer situated at IBR-2 reactor (Dubna, JINR, Russia). The three complete pole figures (110), (200), (211) of α-Fe phase in 5°×5°grid were extracted from a set of 1368 spectra measured for each sample. The samples were cut from rail wheel rim and from transitional zone (between rail wheel hub and wheel disk). It was concluded that the steel modification and some changes in the heat treatment modes of the rail wheels from the experimental (modified) and the conventional (non-modified) steel lead to reorientation of texture component.

First Results from BM@N Technical Run with Deuteron Beam

NASA Astrophysics Data System (ADS)

Baranov, D.; Kapishin, M.; Kulish, E.; Maksymchuk, A.; Mamontova, T.; Pokatashkin, G.; Rufanov, I.; Vasendina, V.; Zinchenko, A.

2018-03-01

BM@N (Baryonic Matter at Nuclotron) is the first experiment to be realized at the accelerator complex of NICA-Nuclotron at JINR (Dubna). The aim of the experiment is to study interactions of relativistic heavy ion beams with a kinetic energy from 1 to 4.5 AGeV with fixed targets. The BM@N set-up at the starting phase of the experiment is introduced. First results of the analysis of minimum bias experimental data collected in the technical run in interactions of the deuteron beam of 4 AGeV with different targets are presented. The spacial, momentum and primary vertex resolution of the GEM tracker are studied. The signal of Lambda-hyperon is reconstructed in the proton-pion invariant mass spectrum. The data results are described by Monte Carlo simulations. The investigation has been performed at the Laboratory of High Energy Physics, JINR.

[Radiobiological effects of total mice irradiation with Bragg's peak protons].

PubMed

Ivanov, A A; Molokanov, A G; Ushakov, I B; Bulynina, T M; Vorozhtsova, S V; Abrosimova, A N; Kryuchkova, D M; Gaevsky, V N

2013-01-01

Outbred CD-1 female mice were irradiated in a proton beam (171 MeV, 5 Gy) on the phasotron at the Joint Institute of Nuclear Research (Dubna, Russia). Radiation was delivered in two points of the depth dose distribution: at the beam entry and on Bragg's peak. Technical requirements for studying the effects of Bragg's peak protons on organism of experimental animals were specified. It was recognized that protons with high linear energy transfer (mean LET = 1.6 keV/microm) cause a more severe damaging effect to the hemopoietic system and cytogenetic apparatus in bone marrow cells as compared with entry protons and 60Co gamma-quanta. It was shown that recovery of the main hemopoietic organs and immunity as well as elimination of chromosomal aberrations take more time following irradiation with Bragg's peak protons but not protons with the energy of 171 MeV.

Target fragments in collisions of 1.8 GeV/nucleon Fe-56 nuclei with photoemulsion nuclei, and the cascade-evaporation model

NASA Technical Reports Server (NTRS)

Dudkin, V. E.; Kovalev, E. E.; Nefedov, N. A.; Antonchik, V. A.; Bogdanov, S. D.; Ostroumov, V. I.; Benton, E. V.; Crawford, H. J.

1995-01-01

Nuclear photographic emulsion is used to study the dependence of the characteristics of target-nucleus fragments on the masses and impact parameters of interacting nuclei. The data obtained are compared in all details with the calculation results made in terms of the Dubna version of the cascade-evaporation model (DCM).

Recoil-α-fission and recoil-α-α-fission events observed in the reaction 48Ca + 243Am

NASA Astrophysics Data System (ADS)

Forsberg, U.; Rudolph, D.; Andersson, L.-L.; Di Nitto, A.; Düllmann, Ch. E.; Fahlander, C.; Gates, J. M.; Golubev, P.; Gregorich, K. E.; Gross, C. J.; Herzberg, R.-D.; Heßberger, F. P.; Khuyagbaatar, J.; Kratz, J. V.; Rykaczewski, K.; Sarmiento, L. G.; Schädel, M.; Yakushev, A.; Åberg, S.; Ackermann, D.; Block, M.; Brand, H.; Carlsson, B. G.; Cox, D.; Derkx, X.; Dobaczewski, J.; Eberhardt, K.; Even, J.; Gerl, J.; Jäger, E.; Kindler, B.; Krier, J.; Kojouharov, I.; Kurz, N.; Lommel, B.; Mistry, A.; Mokry, C.; Nazarewicz, W.; Nitsche, H.; Omtvedt, J. P.; Papadakis, P.; Ragnarsson, I.; Runke, J.; Schaffner, H.; Schausten, B.; Shi, Yue; Thörle-Pospiech, P.; Torres, T.; Traut, T.; Trautmann, N.; Türler, A.; Ward, A.; Ward, D. E.; Wiehl, N.

2016-09-01

Products of the fusion-evaporation reaction 48Ca + 243Am were studied with the TASISpec set-up at the gas-filled separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany. Amongst the detected thirty correlated α-decay chains associated with the production of element Z = 115, two recoil-α-fission and five recoil- α- α-fission events were observed. The latter five chains are similar to four such events reported from experiments performed at the Dubna gas-filled separator, and three such events reported from an experiment at the Berkeley gas-filled separator. The four chains observed at the Dubna gas-filled separator were assigned to start from the 2n-evaporation channel 289115 due to the fact that these recoil- α- α-fission events were observed only at low excitation energies. Contrary to this interpretation, we suggest that some of these recoil- α- α-fission decay chains, as well as some of the recoil- α- α-fission and recoil-α-fission decay chains reported from Berkeley and in this article, start from the 3n-evaporation channel 288115.

Human Development VI: Supracellular Morphogenesis. The Origin of Biological and Cellular Order

PubMed Central

Ventegodt, Søren; Hermansen, Tyge Dahl; Flensborg-Madsen, Trine; Nielsen, Maj Lyck; Merrick, Joav

2006-01-01

Uninterrupted morphogenesis shows the informational potentials of biological organisms. Experimentally disturbed morphogenesis shows the compensational dynamics of the biological informational system, which is the rich informational redundancy. In this paper, we use these data to describe morphogenesis in terms of the development of supracellular levels of the organism, and we define complex epigenesis and supracellular differentiation. We review the phenomena of regeneration and induction of Hydra and amphibians, and the higher animals informational needs for developing their complex nervous systems. We argue, also building on the NO-GO theorem for ontogenesis as chemistry, that the traditional chemical explanations of high-level informational events in ontogenesis, such as transmutation, regeneration, and induction, are insufficient. We analyze the informational dynamics of three embryonic compensatory reactions to different types of disturbances: (1) transmutations of the imaginal discs of insects, (2) regeneration after removal of embryonic tissue, and (3) embryonic induction, where two tissues that normally are separated experimentally are made to influence each other. We describe morphogenesis as a complex bifurcation, and the resulting morphological levels of the organism as organized in a fractal manner and supported by positional information. We suggest that some kind of real nonchemical phenomenon must be taking form in living organisms as an information-carrying dynamic fractal field, causing morhogenesis and supporting the organisms morphology through time. We argue that only such a phenomenon that provides information-directed self-organization to the organism is able to explain the observed dynamic distribution of biological information through morphogenesis and the organism's ability to rejuvenate and heal. PMID:17115082

Transmutation of fullerenes.

PubMed

Cross, R James; Saunders, Martin

2005-03-09

Fullerenes were pyrolyzed by subliming them into a stream of flowing argon gas and then passing them through an oven heated to approximately 1000 degrees C. C(76), C(78), and C(84) all readily lost carbons to form smaller fullerenes. In the case of C(78), some isomerization was seen. Pyrolysis of (3)He@C(76) showed that all or most of the (3)He was lost during the decomposition. C(60) passes through the apparatus with no decomposition and no loss of helium.

Neutron diffraction studies of laser welding residual stresses

NASA Astrophysics Data System (ADS)

Petrov, Peter I.; Bokuchava, Gizo D.; Papushkin, Igor V.; Genchev, Gancho; Doynov, Nikolay; Michailov, Vesselin G.; Ormanova, Maria A.

2016-01-01

The residual stress and microstrain distribution induced by laser beam welding of the low-alloyed C45 steel plate was investigated using high-resolution time-of-flight (TOF) neutron diffraction. The neutron diffraction experiments were performed on FSD diffractometer at the IBR-2 pulsed reactor in FLNP JINR (Dubna, Russia). The experiments have shown that the residual stress distribution across weld seam exhibit typical alternating sign character as it was observed in our previous studies. The residual stress level is varying in the range from -60 MPa to 450 MPa. At the same time, the microstrain level exhibits sharp maxima at weld seam position with maximal level of 4.8·10-3. The obtained experimental results are in good agreement with FEM calculations according to the STAAZ model. The provided numerical model validated with measured data enables to study the influence of different conditions and process parameters on the development of residual welding stresses.

Investigations of 2β decay of {sup 106}Cd and {sup 58}Ni with HPGe spectrometer OBELIX

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rukhadze, E.; Fajt, L.; Hodák, R.

2015-08-17

Investigations of double beta decay processes to excited states of daughter nuclei were performed at the Modane underground laboratory (LSM, France, 4800 m w.e.) using the high sensitivity spectrometer OBELIX [1], which is a common activity of JINR Dubna, IEAP CTU in Prague and LSM. The spectrometer is based on the HPGe detector with the sensitive volume of 600 cm{sup 3} and relative efficiency of 160%. Investigation of resonant neutrino-less double electron capture of {sup 106}Cd was performed with ∼23.2 g of {sup 106}Cd (enrichment of 99.57%) during ∼17 days. The experiment with natural Ni (∼21.7 kg of mass) was also carried out duringmore » ∼47 days. The preliminary experimental limits for 0νEC/EC resonant decay to the excited states of {sup 106}Pd and different modes of β β decay {sup 58}Ni are presented.« less

E-36: The First Proto-Megascience Experiment at NAL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pronskikh, Vitaly S.

E-36, an experiment on small-angle proton-proton scattering, began testing equipment at the National Accelerator Laboratory (NAL) using a newly achieved 100 GeV proton beam on February 12, 1972, marking the beginning of NAL’s experimental program. This experiment, which drew collaborators from NAL, the Joint Institute for Nuclear Research (Dubna, USSR), the University of Rochester (Rochester, New York), and Rockefeller University (New York, New York) was significant not only as a milestone in Fermilab’s history but also as a model of cooperation between the East and West at a time when Cold War tensions still ran high. An examination of themore » origin, operation, and resolution of E-36 and the chain of experiments it spawned reveals the complex interplay of science and politics that drove these experiments as well as seeds of the megascience paradigm that has come to dominate high energy physics research since the 1970s.« less

E-36: First Proto-Megascience Experiment at NAL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pronskikh, Vitaly S.

2016-03-01

E-36, an experiment on small angle proton-proton scattering, began testing equipment in the National Accelerator Laboratory’s newly achieved 100-GeV beam on February 12, 1972, marking the beginning of NAL’s experimental program. This experiment, which drew collaborators from NAL, Joint Institute for Nuclear Research (JINR at Dubna, USSR), the University of Rochester (Rochester, New York) and Rockefeller University (New York City) was significant not only as a milestone in Fermilab’s history but also as a model of cooperation between the East and West at a time when Cold War tensions still ran high. An examination of the origin, operation, and resolutionmore » of E-36 and the chain of experiments it spawned reveals the complex interplay of science and politics that drove these experiments as well as seeds of the megascience paradigm that has come to dominate high-energy physics research since the 1970s.« less

A drift chamber with a new type of straws for operation in vacuum

NASA Astrophysics Data System (ADS)

Azorskiy, N.; Glonti, L.; Gusakov, Yu.; Elsha, V.; Enik, T.; Kakurin, S.; Kekelidze, V.; Kislov, E.; Kolesnikov, A.; Madigozhin, D.; Movchan, S.; Polenkevich, I.; Potrebenikov, Yu.; Samsonov, V.; Shkarovskiy, S.; Sotnikov, S.; Zinchenko, A.; Danielsson, H.; Bendotti, J.; Degrange, J.; Dixon, N.; Lichard, P.; Morant, J.; Palladino, V.; Gomez, F. Perez; Ruggiero, G.; Vergain, M.

2016-07-01

A 2150×2150 mm2 registration area drift chamber capable of working in vacuum is presented. Thin-wall tubes (straws) of a new type are used in the chamber. A large share of these 9.80 mm diameter drift tubes are made in Dubna from metalized 36 μm Mylar film welded along the generatrix using an ultrasonic welding machine created at JINR. The main features of the chamber and some characteristics of the drift tubes are described. Four such chambers with the X, Y, U, V coordinates each, containing 7168 straws in total, are designed and produced at JINR and CERN. They are installed in the vacuum volume of the NA62 setup in order to study the ultra-rare decay K+ →π+ vv bar and to search for and study rare meson decays. In autumn 2014 the chambers were used for the first time for the data taking in the experimental run of the NA62 at CERN's SPS.

E-36: The First Proto-Megascience Experiment at NAL

DOE PAGES

Pronskikh, Vitaly S.

2016-11-03

E-36, an experiment on small-angle proton-proton scattering, began testing equipment at the National Accelerator Laboratory (NAL) using a newly achieved 100 GeV proton beam on February 12, 1972, marking the beginning of NAL’s experimental program. This experiment, which drew collaborators from NAL, the Joint Institute for Nuclear Research (Dubna, USSR), the University of Rochester (Rochester, New York), and Rockefeller University (New York, New York) was significant not only as a milestone in Fermilab’s history but also as a model of cooperation between the East and West at a time when Cold War tensions still ran high. An examination of themore » origin, operation, and resolution of E-36 and the chain of experiments it spawned reveals the complex interplay of science and politics that drove these experiments as well as seeds of the megascience paradigm that has come to dominate high energy physics research since the 1970s.« less

Spallation reaction study for fission products in nuclear waste: Cross section measurements for 137Cs, 90Sr and 107Pd on proton and deuteron

NASA Astrophysics Data System (ADS)

Wang, He; Otsu, Hideaki; Sakurai, Hiroyoshi; Ahn, DeukSoon; Aikawa, Masayuki; Ando, Takashi; Araki, Shouhei; Chen, Sidong; Chiga, Nobuyuki; Doornenbal, Pieter; Fukuda, Naoki; Isobe, Tadaaki; Kawakami, Shunsuke; Kawase, Shoichiro; Kin, Tadahiro; Kondo, Yosuke; Koyama, Shupei; Kubono, Shigeru; Maeda, Yukie; Makinaga, Ayano; Matsushita, Masafumi; Matsuzaki, Teiichiro; Michimasa, Shinichiro; Momiyama, Satoru; Nagamine, Shunsuke; Nakamura, Takashi; Nakano, Keita; Niikura, Megumi; Ozaki, Tomoyuki; Saito, Atsumi; Saito, Takeshi; Shiga, Yoshiaki; Shikata, Mizuki; Shimizu, Yohei; Shimoura, Susumu; Sumikama, Toshiyuki; Söderström, Pär-Anders; Suzuki, Hiroshi; Takeda, Hiroyuki; Takeuchi, Satoshi; Taniuchi, Ryo; Togano, Yasuhiro; Tsubota, Junichi; Uesaka, Meiko; Watanabe, Yasushi; Watanabe, Yukinobu; Wimmer, Kathrin; Yamamoto, Tatsuya; Yoshida, Koichi

2017-09-01

Spallation reactions for the long-lived fission products 137Cs, 90Sr and 107Pd have been studied for the purpose of nuclear waste transmutation. The cross sections on the proton- and deuteron-induced spallation were obtained in inverse kinematics at the RIKEN Radioactive Isotope Beam Factory. Both the target and energy dependences of cross sections have been investigated systematically. and the cross-section differences between the proton and deuteron are found to be larger for lighter fragments. The experimental data are compared with the SPACS semi-empirical parameterization and the PHITS calculations including both the intra-nuclear cascade and evaporation processes.

Fusion power: a challenge for materials science.

PubMed

Duffy, D M

2010-07-28

The selection and design of materials that will withstand the extreme conditions of a fusion power plant has been described as one of the greatest materials science challenges in history. The high particle flux, high thermal load, thermal mechanical stress and the production of transmutation elements combine to produce a uniquely hostile environment. In this paper, the materials favoured for the diverse roles in a fusion power plant are discussed, along with the experimental and modelling techniques that are used to advance the understanding of radiation damage in materials. Areas where further research is necessary are highlighted.

High-Energy Activation Simulation Coupling TENDL and SPACS with FISPACT-II

NASA Astrophysics Data System (ADS)

Fleming, Michael; Sublet, Jean-Christophe; Gilbert, Mark

2018-06-01

To address the needs of activation-transmutation simulation in incident-particle fields with energies above a few hundred MeV, the FISPACT-II code has been extended to splice TENDL standard ENDF-6 nuclear data with extended nuclear data forms. The JENDL-2007/HE and HEAD-2009 libraries were processed for FISPACT-II and used to demonstrate the capabilities of the new code version. Tests of the libraries and comparisons against both experimental yield data and the most recent intra-nuclear cascade model results demonstrate that there is need for improved nuclear data libraries up to and above 1 GeV. Simulations on lead targets show that important radionuclides, such as 148Gd, can vary by more than an order of magnitude where more advanced models find agreement within the experimental uncertainties.

Insight into the Am-O Phase Equilibria: A Thermodynamic Study Coupling High-Temperature XRD and CALPHAD Modeling.

PubMed

Epifano, Enrica; Guéneau, Christine; Belin, Renaud C; Vauchy, Romain; Lebreton, Florent; Richaud, Jean-Christophe; Joly, Alexis; Valot, Christophe; Martin, Philippe M

2017-07-03

In the frame of minor actinide transmutation, americium can be diluted in UO 2 and (U, Pu)O 2 fuels burned in fast neutron reactors. The first mandatory step to foresee the influence of Am on the in-reactor behavior of transmutation targets or fuel is to have fundamental knowledge of the Am-O binary system and, in particular, of the AmO 2-x phase. In this study, we coupled HT-XRD (high-temperature X-ray diffraction) experiments with CALPHAD thermodynamic modeling to provide new insights into the structural properties and phase equilibria in the AmO 2-x -AmO 1.61+x -Am 2 O 3 domain. Because of this approach, we were able for the first time to assess the relationships between temperature, lattice parameter, and hypostoichiometry for fcc AmO 2-x . We showed the presence of a hyperstoichiometric existence domain for the bcc AmO 1.61+x phase and the absence of a miscibility gap in the fcc AmO 2-x phase, contrary to previous representations of the phase diagram. Finally, with the new experimental data, a new CALPHAD thermodynamic model of the Am-O system was developed, and an improved version of the phase diagram is presented.

New Quantum Diffusion Monte Carlo Method for strong field time dependent problems

NASA Astrophysics Data System (ADS)

Kalinski, Matt

2017-04-01

We have recently formulated the Quantum Diffusion Quantum Monte Carlo (QDMC) method for the solution of the time-dependent Schrödinger equation when it is equivalent to the reaction-diffusion system coupled by the highly nonlinear potentials of the type of Shay. Here we formulate a new Time Dependent QDMC method free of the nonlinearities described by the constant stochastic process of the coupled diffusion with transmutation. As before two kinds of diffusing particles (color walkers) are considered but which can further also transmute one into the other. Each of the species undergoes the hypothetical Einstein random walk progression with transmutation. The progressed particles transmute into the particles of the other kind before contributing to or annihilating the other particles density. This fully emulates the Time Dependent Schrödinger equation for any number of quantum particles. The negative sign of the real and the imaginary parts of the wave function is handled by the ``spinor'' densities carrying the sign as the degree of freedom. We apply the method for the exact time-dependent observation of our discovered two-electron Langmuir configurations in the magnetic and circularly polarized fields.

Cone-like rhodopsin expressed in the all-cone retina of the colubrid pine snake as a potential adaptation to diurnality.

PubMed

Bhattacharyya, Nihar; Darren, Benedict; Schott, Ryan K; Tropepe, Vincent; Chang, Belinda S W

2017-07-01

Colubridae is the largest and most diverse family of snakes, with visual systems that reflect this diversity, encompassing a variety of retinal photoreceptor organizations. The transmutation theory proposed by Walls postulates that photoreceptors could evolutionarily transition between cell types in squamates, but few studies have tested this theory. Recently, evidence for transmutation and rod-like machinery in an all-cone retina has been identified in a diurnal garter snake ( Thamnophis ), and it appears that the rhodopsin gene at least may be widespread among colubrid snakes. However, functional evidence supporting transmutation beyond the existence of the rhodopsin gene remains rare. We examined the all-cone retina of another colubrid, Pituophis melanoleucus , thought to be more secretive/burrowing than Thamnophis We found that P. melanoleucus expresses two cone opsins (SWS1, LWS) and rhodopsin (RH1) within the eye. Immunohistochemistry localized rhodopsin to the outer segment of photoreceptors in the all-cone retina of the snake and all opsin genes produced functional visual pigments when expressed in vitro Consistent with other studies, we found that P. melanoleucus rhodopsin is extremely blue-shifted. Surprisingly, P. melanoleucus rhodopsin reacted with hydroxylamine, a typical cone opsin characteristic. These results support the idea that the rhodopsin-containing photoreceptors of P. melanoleucus are the products of evolutionary transmutation from rod ancestors, and suggest that this phenomenon may be widespread in colubrid snakes. We hypothesize that transmutation may be an adaptation for diurnal, brighter-light vision, which could result in increased spectral sensitivity and chromatic discrimination with the potential for colour vision. © 2017. Published by The Company of Biologists Ltd.

The Changing Nature of Warfare, the Factors Mediating Future Conflict, and Implications for SOF

DTIC Science & Technology

2006-04-01

most commonly used vernacular today, one is describing the person’s sexual orientation.13 The English language is replete with other words that have...countries and those that are technologically more advanced, primarily due to labor cost differentials. Globaliza- tion has transmuted economics from a...fascination with forensic sci- ences, ala the acclaimed television pro- gram CSI, has transmuted from civilian criminal proceedings to microscopic

Remanent Activation in the Mini-SHINE Experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Micklich, Bradley J.

2015-04-16

Argonne National Laboratory is assisting SHINE Medical Technologies in developing a domestic source of the medical isotope 99Mo through the fission of low-enrichment uranium in a uranyl sulfate solution. In Phase 2 of these experiments, electrons from a linear accelerator create neutrons by interacting in a depleted uranium target, and these neutrons are used to irradiate the solution. The resulting neutron and photon radiation activates the target, the solution vessels, and a shielded cell that surrounds the experimental apparatus. When the experimental campaign is complete, the target must be removed into a shielding cask, and the experimental components must bemore » disassembled. The radiation transport code MCNPX and the transmutation code CINDER were used to calculate the radionuclide inventories of the solution, the target assembly, and the shielded cell, and to determine the dose rates and shielding requirements for selected removal scenarios for the target assembly and the solution vessels.« less

Summary of Research Activities. Academic Departments, 1979-1980.

DTIC Science & Technology

1979-10-01

studied, including recycling, geologic storage, transmutation , ejection from earth, and seabed disposal. Currently, the most favored methods are...official society. (4) The poem ultimately celebrates in a sort of poetic eucharist the regenerative power of poetry to transmute the bread and wine of...Union prevails. Such a view becomes commonplace after Burr’s political enemies attack him as a Catiline, Cain, and sexual predator. Influenced by these

Separation of Long-Lived Fission Products Tc-99 and I-129 from Synthetic Effluents by Crown Ethers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paviet-Hartmann, P.; Hartmann, T.

2006-07-01

To minimize significantly the radio-toxic inventory of nuclear geological repositories to come as well as to reduce the potential of radionuclides migration and to minimize long-term exposure, the concept of partitioning and transmutation (P/T) of nuclear waste is currently discussed. Transmutation offers the possibility to convert radio-toxic radionuclides with long half-lives into radionuclides of shorter half-lives, less toxic isotopes, or even into stable isotopes. Besides the most prominent isotopes of neptunium, plutonium, americium, and curium, the long-lived fission products Tc-99 and I-129 (half-lives of 2.13 x 10{sup 5} years, and 1.57 x 10{sup 7} years, respectively) are promising candidates formore » transmutation in order to prevent their migration from a nuclear repository. Partitioning and transmutation of the most radio-toxic radionuclides will not only minimize the nuclear waste load but most importantly will significantly reduce the long-term radio-toxic hazard of nuclear waste repositories to come. Prior to the deployment of partitioning and transmutation, selective extraction techniques are required to separate the radionuclides of concern. Since the discovery of crown ethers by C. Pedersen, various applications of crown ethers have drawn much attention. Although liquid-liquid extraction of alkali and alkali earth metals by crown ethers has been extensively studied, little data is available on the extraction of Tc-99 and I-129 by crown ethers. The methods developed herein for the specific extraction of Tc-99 and I-129 provide recommendations in support of their selectively extraction from liquid radioactive waste streams, mainly ILW. We report data on the solvent extraction of Tc-99 and I-129 from synthetic effluents by six crown ethers of varying cavity dimensions and derivatization. To satisfy the needs of new extractant systems we are demonstrating that crown ether (CE) based systems have the potential to serve as selective extractants for

Element 117

ScienceCinema

None

2018-06-12

An international team of scientists from Russia and the United States, including two Department of Energy national laboratories and two universities, has discovered the newest superheavy element, element 117. The team included scientists from the Joint Institute of Nuclear Research (Dubna, Russia), the Research Institute for Advanced Reactors (Dimitrovgrad), Lawrence Livermore National Laboratory, Oak Ridge National Laboratory, Vanderbilt University, and the University of Nevada, Las Vegas.

PREFACE: 15th International Conference on Strangeness in Quark Matter (SQM2015)

NASA Astrophysics Data System (ADS)

Alvarez-Castillo, D.; Blaschke, D.; Kekelidze, V.; Matveev, V.; Sorin, A.

2016-01-01

The 15th International Conference Strangeness in Quark Matter (SQM) took place at the Veksler and Baldin Laboratory of High Energy Physics (VBLHEP) of the Joint Institute for Nuclear Research (JINR) in Dubna in the period July 6 -11, with a record participation of 244 people from 31 countries! The previous meeting of the series in Birmingham 2013 had collected 158 physicists from 25 countries [J. Phys. Conf. Ser. 509, 011001 (2014)]. At SQM-2015, there was also a record participation of young scientist; every 4th conference attendee did not yet hold a PhD degree! There was a special program of 4 general lectures, a devoted session of parallel talks for Young Talents and the Helmholtz International Summer School (HISS) with 16 lecturers on the topics regarding Dense Matter (29.06.-11.07.) as a satellite event at the Bogoliubov Laboratory of Theoretical Physics (BLTP) and at VBLHEP. Another satellite event was the Round TableWorkshop on Physics at NICA, jointly organized by JINR and the Republic of South Africa on July 5, 2015. The selection of Dubna as the place for SQM-2015 conference by the International Advisory Committee (IAC) demonstrates the broad interest of the community in the progress of the Russian Megascience Project on the Nuclotron-based Ion Collider Facility (NICA) hosted at JINR Dubna. In a few years from now the experiments planned at NICA will produce data that provide new information of unprecedented accuracy which will help to answer some of the key questions which are topical at this conference. The SQM-2015 conference had an ambitious scientific program with 38 plenary talks, 97 parallel talks in 7 topical directions and 39 posters reporting the state of the research and the future directions in the fields of strangeness, heavy avors and bulk physics, suggested by the IAC to be the subtitle of the conference from 2016 onwards. Most of the contributions are represented in these Proceedings which we recommend to the community! We gratefully

NEUTRON FLUX INTENSITY DETECTION

DOEpatents

Russell, J.T.

1964-04-21

A method of measuring the instantaneous intensity of neutron flux in the core of a nuclear reactor is described. A target gas capable of being transmuted by neutron bombardment to a product having a resonance absorption line nt a particular microwave frequency is passed through the core of the reactor. Frequency-modulated microwave energy is passed through the target gas and the attenuation of the energy due to the formation of the transmuted product is measured. (AEC)

Status of the Neutron Capture Measurement on 237Np with the DANCE Array at LANSCE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Esch, E.-I.; Bond, E.M.; Bredeweg, T. A.

2005-05-24

Neptunium-237 is a major constituent of spent nuclear fuel. Estimates place the amount of 237Np bound for the Yucca Mountain high-level waste repository at 40 metric tons. The Department of Energy's Advanced Fuel Cycle Initiative program is evaluating methods for transmuting the actinide waste that will be generated by future operation of commercial nuclear power plants. The critical parameter that defines the transmutation efficiency of actinide isotopes is the neutron fission-to-capture ratio for the particular isotope in a given neutron spectrum. The calculation of transmutation efficiency therefore requires accurate fission and capture cross sections. Current 237Np evaluations available for transmutermore » system studies show significant discrepancies in both the fission and capture cross sections in the energy regions of interest. Herein we report on 237Np (n,{gamma}) measurements using the recently commissioned DANCE array.« less

Convenience experimentation.

PubMed

Krohs, Ulrich

2012-03-01

Systems biology aims at explaining life processes by means of detailed models of molecular networks, mainly on the whole-cell scale. The whole cell perspective distinguishes the new field of systems biology from earlier approaches within molecular cell biology. The shift was made possible by the high throughput methods that were developed for gathering 'omic' (genomic, proteomic, etc.) data. These new techniques are made commercially available as semi-automatic analytic equipment, ready-made analytic kits and probe arrays. There is a whole industry of supplies for what may be called convenience experimentation. My paper inquires some epistemic consequences of strong reliance on convenience experimentation in systems biology. In times when experimentation was automated to a lesser degree, modeling and in part even experimentation could be understood fairly well as either being driven by hypotheses, and thus proceed by the testing of hypothesis, or as being performed in an exploratory mode, intended to sharpen concepts or initially vague phenomena. In systems biology, the situation is dramatically different. Data collection became so easy (though not cheap) that experimentation is, to a high degree, driven by convenience equipment, and model building is driven by the vast amount of data that is produced by convenience experimentation. This results in a shift in the mode of science. The paper shows that convenience driven science is not primarily hypothesis-testing, nor is it in an exploratory mode. It rather proceeds in a gathering mode. This shift demands another shift in the mode of evaluation, which now becomes an exploratory endeavor, in response to the superabundance of gathered data. Copyright © 2011 Elsevier Ltd. All rights reserved.

100th anniversary of the birth of B M Pontecorvo (Scientific session of the Physical Sciences Division of the Russian Academy of Sciences, 2 September 2013)

NASA Astrophysics Data System (ADS)

2014-05-01

A scientific session "Prospects of Studies in Neutrino Particle Physics and Astrophysics," of the Physical Sciences Division of the Russian Academy of Sciences (DPS RAS), devoted to the centenary of B M Pontecorvo, was held on 2-3 September 2014 at the JINR international conference hall (Dubna, Moscow region).The following reports were put on the session agenda as posted on the website http://www.gpad.ac.ru of the RAS Physical Sciences Division: (1) Kudenko Yu G (Institute for Nuclear Research, RAS, Moscow; Moscow Institute of Physics and Technology, Dolgoprudnyi, Moscow region; National Research Nuclear University MEPhI, Moscow) "Long-baseline neutrino accelerator experiments: results and prospects";(2) Spiering Ch (Deutsches Elektronen-Synchrotron (DESY), Germany) "Results obtained by ICECUBE and prospects of neutrino astronomy";(3) Barabash A S (Alikhanov Institute for Theoretical and Experimental Physics, Moscow) "Double beta decay experiments: current status and prospects";(4) Bilenky S M (Joint Institute for Nuclear Research, Dubna, Moscow region; Technische Universitat M'unchen, Garching, Germany) "Bruno Pontecorvo and the neutrino";(5) Olshevskiy A G (Joint Institute for Nuclear Research, Dubna, Moscow region) "Reactor neutrino experiments: results and prospects";(6) Gavrin V N (Institute for Nuclear Research, RAS, Moscow) "Low-energy neutrino research at the Baksan Neutrino Laboratory";(7) Gorbunov D S (Institute for Nuclear Research, RAS, Moscow): "Sterile neutrinos and their role in particle physics and cosmology";(8) Derbin A V (Konstantinov Petersburg Nuclear Physics Institute, Gatchina, Leningrad region) "Solar neutrino experiments";(9) Rubakov V A (Institute for Nuclear Research, RAS, Moscow) "Prospects of studies in the field of neutrino particle physics and astrophysics." An article by V N Gavrin, close in essence to talk 6, was published in Usp. Fiz. Nauk 181 (9), 975 (2011) [Phys. Usp. 54 (9) 941 (2011)]. Articles by V A Rubakov, close in essence

Relation between experimental and non-experimental study designs. HB vaccines: a case study.

PubMed

Jefferson, T; Demicheli, V

1999-01-01

To examine the relation between experimental and non-experimental study design in vaccinology. Assessment of each study design's capability of testing four aspects of vaccine performance, namely immunogenicity (the capacity to stimulate the immune system), duration of immunity conferred, incidence and seriousness of side effects, and number of infections prevented by vaccination. Experimental and non-experimental studies on hepatitis B (HB) vaccines in the Cochrane Vaccines Field Database. Experimental and non-experimental vaccine study designs are frequently complementary but some aspects of vaccine quality can only be assessed by one of the types of study. More work needs to be done on the relation between study quality and its significance in terms of effect size.

The Automation of the Transonic Experimental Facility (TEF) and the Aerodynamic Experimental Facility (AEF)

DTIC Science & Technology

2015-10-01

ARL-TR-7506 ● OCT 2015 US Army Research Laboratory The Automation of the Transonic Experimental Facility (TEF) and the...Laboratory The Automation of the Transonic Experimental Facility (TEF) and the Aerodynamic Experimental Facility (AEF) by Charith R Ranawake Weapons...To) 05/2015–08/2015 4. TITLE AND SUBTITLE The Automation of the Transonic Experimental Facility (TEF) and the Aerodynamic Experimental Facility

Is animal experimentation fundamental?

PubMed

d'Acampora, Armando José; Rossi, Lucas Félix; Ely, Jorge Bins; de Vasconcellos, Zulmar Acciolli

2009-01-01

The understanding about the utilization of experimental animals in scientific research and in teaching is many times a complex issue. Special attention needs to be paid to attain the understanding by the general public of the importance of animal experimentation in experimental research and in undergraduate medical teaching. Experimental teaching and research based on the availability of animals for experimentation is important and necessary for the personal and scientific development of the physician-to-be. The technological arsenal which intends to mimic experimentation animals and thus fully replace their use many times does not prove to be compatible with the reality of the living animal. The purpose of this paper is to discuss aspects concerning this topic, bringing up an issue which is complex and likely to arouse in-depth reflections.

Relation between experimental and non-experimental study designs. HB vaccines: a case study

PubMed Central

Jefferson, T.; Demicheli, V.

1999-01-01

STUDY OBJECTIVE: To examine the relation between experimental and non- experimental study design in vaccinology. DESIGN: Assessment of each study design's capability of testing four aspects of vaccine performance, namely immunogenicity (the capacity to stimulate the immune system), duration of immunity conferred, incidence and seriousness of side effects, and number of infections prevented by vaccination. SETTING: Experimental and non-experimental studies on hepatitis B (HB) vaccines in the Cochrane Vaccines Field Database. RESULTS: Experimental and non-experimental vaccine study designs are frequently complementary but some aspects of vaccine quality can only be assessed by one of the types of study. More work needs to be done on the relation between study quality and its significance in terms of effect size.   PMID:10326054

Study of secondary neutron interactions with 232Th, 129I, and 127I nuclei with the uranium assembly “QUINTA” at 2, 4, and 8GeV deuteron beams of the JINR Nuclotron accelerator

DOE PAGES

Adam, J.; Chilap, V. V.; Furman, V. I.; ...

2015-11-04

The natural uranium assembly, “QUINTA”, was irradiated with 2, 4, and 8 GeV deuterons. The 232Th, 127I, and 129I samples have been exposed to secondary neutrons produced in the assembly at a 20-cm radial distance from the deuteron beam axis. The spectra of gamma rays emitted by the activated 232Th, 127I, and 129I samples have been analyzed and several tens of product nuclei have been identified. For each of those products, neutron-induced reaction rates have been determined. The transmutation power for the 129I samples is estimated. Furthermore, experimental results were compared to those calculated with well-known stochastic and deterministic codes.

Studies on Materials for Heavy-Liquid-Metal-Cooled Reactors in Japan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Minoru Takahashi; Masayuki Igashira; Toru Obara

2002-07-01

Recent studies on materials for the development of lead-bismuth (Pb-Bi)-cooled fast reactors (FR) and accelerator-driven sub-critical systems (ADS) in Japan are reported. The measurement of the neutron cross section of Bi to produce {sup 210}Po, the removal experiment of Po contamination and steel corrosion test in Pb-Bi flow were performed in Tokyo Institute of Technology. A target material corrosion test was performed in the project of Transmutation Experimental Facility for ADS in Japan Atomic Energy Research Institute (JAERI). Steel corrosion test was started in Mitsui Engineering and Shipbuilding Co., LTD (MES). The feasibility study for FR cycle performed in Japanmore » Nuclear Cycle Institute (JNC) are described. (authors)« less

Study of secondary neutron interactions with ²³²Th, ¹²⁹I, and ¹²⁷I nuclei with the uranium assembly "QUINTA" at 2, 4, and 8 GeV deuteron beams of the JINR Nuclotron accelerator.

PubMed

Adam, J; Chilap, V V; Furman, V I; Kadykov, M G; Khushvaktov, J; Pronskikh, V S; Solnyshkin, A A; Stegailov, V I; Suchopar, M; Tsoupko-Sitnikov, V M; Tyutyunnikov, S I; Vrzalova, J; Wagner, V; Zavorka, L

2016-01-01

The natural uranium assembly, "QUINTA", was irradiated with 2, 4, and 8GeV deuterons. The (232)Th, (127)I, and (129)I samples have been exposed to secondary neutrons produced in the assembly at a 20-cm radial distance from the deuteron beam axis. The spectra of gamma rays emitted by the activated (232)Th, (127)I, and (129)I samples have been analyzed and several tens of product nuclei have been identified. For each of those products, neutron-induced reaction rates have been determined. The transmutation power for the (129)I samples is estimated. Experimental results were compared to those calculated with well-known stochastic and deterministic codes. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Chymistry of "The Learned Dr Plot" (1640-96).

PubMed

Roos, Anna Marie

2014-01-01

In the seventeenth century, there were developing norms of openness in the presentation of scientific knowledge that were at odds with traditions of secrecy among chymists, particularly practitioners of chrysopoeia, or the transmutation of metals. This chapter analyzes how Dr. Robert Plot, the first professor of chymistry at Oxford, negotiated these boundaries within an institutional context. I first delineate his chymical and experimental practice, which incorporated procedures from medieval alchemical sources, particularly the Lullian corpus, as well as more novel practices from seventeenth-century chymistry. Then, I analyze how personal and institutional ambitions and economic considerations shaped to what extent Plot negotiated the boundaries between secrecy and the public dissemination of chymical knowledge.

The measurement programme at the neutron time-of-flight facility n_TOF at CERN

NASA Astrophysics Data System (ADS)

Gunsing, F.; Aberle, O.; Andrzejewski, J.; Audouin, L.; Bécares, V.; Bacak, M.; Balibrea-Correa, J.; Barbagallo, M.; Barros, S.; Bečvář, F.; Beinrucker, C.; Belloni, F.; Berthoumieux, E.; Billowes, J.; Bosnar, D.; Brown, A.; Brugger, M.; Caamaño, M.; Calviño, F.; Calviani, M.; Cano-Ott, D.; Cardella, R.; Casanovas, A.; Castelluccio, D. M.; Cerutti, F.; Chen, Y. H.; Chiaveri, E.; Colonna, N.; Cortés-Giraldo, M. A.; Cortés, G.; Cosentino, L.; Damone, L. A.; Deo, K.; Diakaki, M.; Domingo-Pardo, C.; Dressler, R.; Dupont, E.; Durán, I.; Fernández-Domínguez, B.; Ferrari, A.; Ferreira, P.; Finocchiaro, P.; Frost, R. J. W.; Furman, V.; Ganesan, S.; García, A. R.; Gawlik, A.; Gheorghe, I.; Gilardoni, S.; Glodariu, T.; Gonçalves, I. F.; González, E.; Goverdovski, A.; Griesmayer, E.; Guerrero, C.; Göbel, K.; Harada, H.; Heftrich, T.; Heinitz, S.; Hernández-Prieto, A.; Heyse, J.; Jenkins, D. G.; Jericha, E.; Käppeler, F.; Kadi, Y.; Kalamara, A.; Katabuchi, T.; Kavrigin, P.; Ketlerov, V.; Khryachkov, V.; Kimura, A.; Kivel, N.; Kokkoris, M.; Krtička, M.; Kurtulgil, D.; Leal-Cidoncha, E.; Lederer, C.; Leeb, H.; Lerendegui, J.; Licata, M.; Meo, S. Lo; Lonsdale, S. J.; Losito, R.; Macina, D.; Marganiec, J.; Martínez, T.; Masi, A.; Massimi, C.; Mastinu, P.; Mastromarco, M.; Matteucci, F.; Maugeri, E. A.; Mazzone, A.; Mendoza, E.; Mengoni, A.; Milazzo, P. M.; Mingrone, F.; Mirea, M.; Montesano, S.; Musumarra, A.; Nolte, R.; Negret, A.; Oprea, A.; Palomo-Pinto, F. R.; Paradela, C.; Patronis, N.; Pavlik, A.; Perkowski, J.; Porras, I.; Praena, J.; Quesada, J. M.; Radeck, D.; Rajeev, K.; Rauscher, T.; Reifarth, R.; Riego-Perez, A.; Robles, M.; Rout, P.; Rubbia, C.; Ryan, J. A.; Sabaté-Gilarte, M.; Saxena, A.; Schillebeeckx, P.; Schmidt, S.; Schumann, D.; Sedyshev, P.; Smith, A. G.; Sosnin, N. V.; Stamatopoulos, A.; Suryanarayana, S. V.; Tagliente, G.; Tain, J. L.; Tarifeño-Saldivia, A.; Tarrío, D.; Tassan-Got, L.; Tsinganis, A.; Valenta, S.; Vannini, G.; Variale, V.; Vaz, P.; Ventura, A.; Vlachoudis, V.; Vlastou, R.; Wallner, A.; Warren, S.; Weigand, M.; Weiss, C.; Wolf, C.; Woods, P. J.; Wright, T.; Žugec, P.

2017-09-01

Neutron-induced reaction cross sections are important for a wide variety of research fields ranging from the study of nuclear level densities, nucleosynthesis to applications of nuclear technology like design, and criticality and safety assessment of existing and future nuclear reactors, radiation dosimetry, medical applications, nuclear waste transmutation, accelerator-driven systems and fuel cycle investigations. Simulations and calculations of nuclear technology applications largely rely on evaluated nuclear data libraries. The evaluations in these libraries are based both on experimental data and theoretical models. CERN's neutron time-of-flight facility n_TOF has produced a considerable amount of experimental data since it has become fully operational with the start of its scientific measurement programme in 2001. While for a long period a single measurement station (EAR1) located at 185 m from the neutron production target was available, the construction of a second beam line at 20 m (EAR2) in 2014 has substantially increased the measurement capabilities of the facility. An outline of the experimental nuclear data activities at n_TOF will be presented.

The Question of Education Science: "Experiment"ism Versus "Experimental"ism

ERIC Educational Resources Information Center

Howe, Kenneth R.

2005-01-01

The ascendant view in the current debate about education science -- experimentism -- is a reassertion of the randomized experiment as the methodological gold standard. Advocates of this view have ignored, not answered, long-standing criticisms of the randomized experiment: its frequent impracticality, its lack of external validity, its confinement…

Experimental Design and Some Threats to Experimental Validity: A Primer

ERIC Educational Resources Information Center

Skidmore, Susan

2008-01-01

Experimental designs are distinguished as the best method to respond to questions involving causality. The purpose of the present paper is to explicate the logic of experimental design and why it is so vital to questions that demand causal conclusions. In addition, types of internal and external validity threats are discussed. To emphasize the…

Condensed Matter Nuclear Science

NASA Astrophysics Data System (ADS)

Biberian, Jean-Paul

2006-02-01

into characteristics of X-ray emission laser beams from solidstate cathode medium of high-current glow discharge / A. B. Karabut. Charged particles from Ti and Pd foils / L. Kowalski ... [et al.]. Cr-39 track detectors in cold fusion experiments: review and perspectives / A. S. Roussetski. Energetic particle shower in the vapor from electrolysis / R. A. Oriani and J. C. Fisher. Nuclear reactions produced in an operating electrolysis cell / R. A. Oriani and J. C. Fisher. Evidence of microscopic ball lightning in cold fusion experiments / E. H. Lewis. Neutron emission from D[symbol] gas in magnetic fields under low temperature / T. Mizuno ... [et al.]. Energetic charged particle emission from hydrogen-loaded Pd and Ti cathodes and its enhancement by He-4 implantation / A. G. Lipson ... [et al.]. H-D permeation. Observation of nuclear transmutation reactions induced by D[symbol] gas permeation through Pd complexes / Y. Iwamura ... [et al.]. Deuterium (hydrogen) flux permeating through palladium and condensed matter nuclear science / Q. M. Wei ... [et al.]. Triggering. Precursors and the fusion reactions in polarized Pd/D-D[symbol]O system: effect of an external electric field / S. Szpak, P. A. Mosier-Boss, and F. E. Gordon. Calorimetric and neutron diagnostics of liquids during laser irradiation / Yu. N. Bazhutov ... [et al.]. Anomalous neutron capture and plastic deformation of Cu and Pd cathodes during electrolysis in a weak thermalized neutron field: evidence of nuclei-lattice exchange / A. G. Lipson and G. H. Miley. H-D loading. An overview of experimental studies on H/Pd over-loading with thin Pd wires and different electrolytic solutions / A. Spallone ... [et al.] -- 3. Transmutations. Photon and particle emission, heat production, and surface transformation in Ni-H system / E. Campari ... [et al.]. Surface analysis of hydrogen-loaded nickel alloys / E. Campari ... [et al.]. Low-energy nuclear reactions and the leptonic monopole / G. Lochak and L. Urutskoev. Results

The physics of sub-critical lattices in accelerator driven hybrid systems: The MUSE experiments in the MASURCA facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chauvin, J. P.; Lebrat, J. F.; Soule, R.

Since 1991, the CEA has studied the physics of hybrid systems, involving a sub-critical reactor coupled with an accelerator. These studies have provided information on the potential of hybrid systems to transmute actinides and, long lived fission products. The potential of such a system remains to be proven, specifically in terms of the physical understanding of the different phenomena involved and their modelling, as well as in terms of experimental validation of coupled systems, sub-critical environment/accelerator. This validation must be achieved through mock-up studies of the sub-critical environments coupled to a source of external neutrons. The MUSE-4 mock-up experiment ismore » planed at the MASURCA facility and will use an accelerator coupled to a tritium target. The great step between the generator used in the past and the accelerator will allow to increase the knowledge in hybrid physic and to decrease the experimental biases and the measurement uncertainties.« less

Questioning and Experimentation

ERIC Educational Resources Information Center

Mutanen, Arto

2014-01-01

The paper is a philosophical analysis of experimentation. The philosophical framework of the analysis is the interrogative model of inquiry developed by Hintikka. The basis of the model is explicit and well-formed logic of questions and answers. The framework allows us to formulate a flexible logic of experimentation. In particular, the formulated…

Cross section measurement of residues produced in proton- and deuteron-induced spallation reactions on 93Zr at 105 MeV/u using the inverse kinematics method

NASA Astrophysics Data System (ADS)

Kawase, Shoichiro; Watanabe, Yukinobu; Wang, He; Otsu, Hideaki; Sakurai, Hiroyoshi; Takeuchi, Satoshi; Togano, Yasuhiro; Nakamura, Takashi; Maeda, Yukie; Ahn, Deuk Soon; Aikawa, Masayuki; Araki, Shouhei; Chen, Sidong; Chiga, Nobuyuki; Doornenbal, Pieter; Fukuda, Naoki; Ichihara, Takashi; Isobe, Tadaaki; Kawakami, Shunsuke; Kin, Tadahiro; Kondo, Yosuke; Koyama, Shunpei; Kubo, Toshiyuki; Kubono, Shigeru; Kurokawa, Meiko; Makinaga, Ayano; Matsushita, Masafumi; Matsuzaki, Teiichiro; Michimasa, Shin'ichiro; Momiyama, Satoru; Nagamine, Shunsuke; Nakano, Keita; Niikura, Megumi; Ozaki, Tomoyuki; Saito, Atsumi; Saito, Takeshi; Shiga, Yoshiaki; Shikata, Mizuki; Shimizu, Yohei; Shimoura, Susumu; Sumikama, Toshiyuki; Söderström, Pär-Anders; Suzuki, Hiroshi; Takeda, Hiroyuki; Taniuchi, Ryo; Tsubota, Jun'ichi; Watanabe, Yasushi; Wimmer, Kathrin; Yamamoto, Tatsuya; Yoshida, Koichi

2017-09-01

Isotopic production cross sections in the proton- and deuteron-induced spallation reactions on 93Zr at an energy of 105 MeV/u were measured in inverse kinematics conditions for the development of realistic nuclear transmutation processes for long-lived fission products (LLFPs) with neutron and light-ion beams. The experimental results were compared to the PHITS calculations describing the intra-nuclear cascade and evaporation processes. Although an overall agreement was obtained, a large overestimation of the production cross sections for the removal of a few nucleons was seen. A clear shell effect associated with the neutron magic number N = 50 was observed in the measured isotopic production yields of Zr and Y isotopes, which can be reproduced reasonably by the PHITS calculation.

MYRRHA: A multipurpose nuclear research facility

NASA Astrophysics Data System (ADS)

Baeten, P.; Schyns, M.; Fernandez, Rafaël; De Bruyn, Didier; Van den Eynde, Gert

2014-12-01

MYRRHA (Multi-purpose hYbrid Research Reactor for High-tech Applications) is a multipurpose research facility currently being developed at SCK•CEN. MYRRHA is based on the ADS (Accelerator Driven System) concept where a proton accelerator, a spallation target and a subcritical reactor are coupled. MYRRHA will demonstrate the ADS full concept by coupling these three components at a reasonable power level to allow operation feedback. As a flexible irradiation facility, the MYRRHA research facility will be able to work in both critical as subcritical modes. In this way, MYRRHA will allow fuel developments for innovative reactor systems, material developments for GEN IV and fusion reactors, and radioisotope production for medical and industrial applications. MYRRHA will be cooled by lead-bismuth eutectic and will play an important role in the development of the Pb-alloys technology needed for the LFR (Lead Fast Reactor) GEN IV concept. MYRRHA will also contribute to the study of partitioning and transmutation of high-level waste. Transmutation of minor actinides (MA) can be completed in an efficient way in fast neutron spectrum facilities, so both critical reactors and subcritical ADS are potential candidates as dedicated transmutation systems. However critical reactors heavily loaded with fuel containing large amounts of MA pose reactivity control problems, and thus safety problems. A subcritical ADS operates in a flexible and safe manner, even with a core loading containing a high amount of MA leading to a high transmutation rate. In this paper, the most recent developments in the design of the MYRRHA facility are presented.

Graphical Models for Quasi-Experimental Designs

ERIC Educational Resources Information Center

Kim, Yongnam; Steiner, Peter M.; Hall, Courtney E.; Su, Dan

2016-01-01

Experimental and quasi-experimental designs play a central role in estimating cause-effect relationships in education, psychology, and many other fields of the social and behavioral sciences. This paper presents and discusses the causal graphs of experimental and quasi-experimental designs. For quasi-experimental designs the authors demonstrate…

Experimentation in software engineering

NASA Technical Reports Server (NTRS)

Basili, V. R.; Selby, R. W.; Hutchens, D. H.

1986-01-01

Experimentation in software engineering supports the advancement of the field through an iterative learning process. In this paper, a framework for analyzing most of the experimental work performed in software engineering over the past several years is presented. A variety of experiments in the framework is described and their contribution to the software engineering discipline is discussed. Some useful recommendations for the application of the experimental process in software engineering are included.

Experimental philosophy.

PubMed

Knobe, Joshua; Buckwalter, Wesley; Nichols, Shaun; Robbins, Philip; Sarkissian, Hagop; Sommers, Tamler

2012-01-01

Experimental philosophy is a new interdisciplinary field that uses methods normally associated with psychology to investigate questions normally associated with philosophy. The present review focuses on research in experimental philosophy on four central questions. First, why is it that people's moral judgments appear to influence their intuitions about seemingly nonmoral questions? Second, do people think that moral questions have objective answers, or do they see morality as fundamentally relative? Third, do people believe in free will, and do they see free will as compatible with determinism? Fourth, how do people determine whether an entity is conscious?

Reconstruction of dynamic structures of experimental setups based on measurable experimental data only

NASA Astrophysics Data System (ADS)

Chen, Tian-Yu; Chen, Yang; Yang, Hu-Jiang; Xiao, Jing-Hua; Hu, Gang

2018-03-01

Nowadays, massive amounts of data have been accumulated in various and wide fields, it has become today one of the central issues in interdisciplinary fields to analyze existing data and extract as much useful information as possible from data. It is often that the output data of systems are measurable while dynamic structures producing these data are hidden, and thus studies to reveal system structures by analyzing available data, i.e., reconstructions of systems become one of the most important tasks of information extractions. In the past, most of the works in this respect were based on theoretical analyses and numerical verifications. Direct analyses of experimental data are very rare. In physical science, most of the analyses of experimental setups were based on the first principles of physics laws, i.e., so-called top-down analyses. In this paper, we conducted an experiment of “Boer resonant instrument for forced vibration” (BRIFV) and inferred the dynamic structure of the experimental set purely from the analysis of the measurable experimental data, i.e., by applying the bottom-up strategy. Dynamics of the experimental set is strongly nonlinear and chaotic, and itʼs subjects to inevitable noises. We proposed to use high-order correlation computations to treat nonlinear dynamics; use two-time correlations to treat noise effects. By applying these approaches, we have successfully reconstructed the structure of the experimental setup, and the dynamic system reconstructed with the measured data reproduces good experimental results in a wide range of parameters.

Animal experimentation.

PubMed

Kolar, Roman

2006-01-01

Millions of animals are used every year in often times extremely painful and distressing scientific procedures. Legislation of animal experimentation in modern societies is based on the supposition that this is ethically acceptable when certain more or less defined formal (e.g. logistical, technical) demands and ethical principles are met. The main parameters in this context correspond to the "3Rs" concept as defined by Russel and Burch in 1959, i.e. that all efforts to replace, reduce and refine experiments must be undertaken. The licensing of animal experiments normally requires an ethical evaluation process, often times undertaken by ethics committees. The serious problems in putting this idea into practice include inter alia unclear conditions and standards for ethical decisions, insufficient management of experiments undertaken for specific (e.g. regulatory) purposes, and conflicts of interest of ethics committees' members. There is an ongoing societal debate about ethical issues of animal use in science. Existing EU legislation on animal experimentation for cosmetics testing is an example of both the public will for setting clear limits to animal experiments and the need to further critically examine other fields and aspects of animal experimentation.

New results of Δσ L( np) at high energies

NASA Astrophysics Data System (ADS)

Sharov, V. I.; Adiasevich, B. P.; Anischenko, N. G.; Antonenko, V. G.; Averichev, S. A.; Azhgirey, L. S.; Bartenev, V. D.; Bazhanov, N. A.; Belyaev, A. A.; Blinov, N. A.; Borisov, N. S.; Borzakov, S. B.; Borzunov, Yu. T.; Bushuev, Yu. P.; Chernenko, L. P.; Chernykh, E. V.; Chumakov, V. F.; Dolgh, S. A.; Fedorov, A. N.; Fimushkin, V. V.; Finger, M.; Finger, M.; Golovanov, L. B.; Gurevich, G. M.; Janata, A.; Kirillov, A. D.; Kolomiets, V. G.; Komogorov, E. V.; Kopylov, S. A.; Kovalenko, A. D.; Kovalev, A. I.; Krasnov, V. A.; Krstonoshich, P.; Kuzmin, E. S.; Ladygin, V. P.; Lazarev, A. B.; Lehar, F.; de Lesquen, A.; Liburg, M. Yu.; Livanov, A. N.; Lukhanin, A. A.; Maniakov, P. K.; Matafonov, V. N.; Matyushevsky, E. A.; Moroz, V. D.; Morozov, A. A.; Neganov, A. B.; Nikolaevsky, G. P.; Nomofilov, A. A.; Panteleev, Tz.; Pilipenko, Yu. K.; Pisarev, I. L.; Plis, Yu. A.; Polunin, Yu. P.; Prokofiev, A. N.; Prytkov, V. Yu.; Rukoyatkin, P. A.; Schedrov, V. A.; Schevelev, O. N.; Shilov, S. N.; Shishov, Yu. A.; Shutov, V. B.; Slunečka, M.; Slunečková, V.; Starikov, A. Yu.; Stoletov, G. D.; Strunov, L. N.; Svetov, A. L.; Usov, Yu. A.; Vasiliev, T.; Volkov, V. I.; Vorobiev, E. I.; Yudin, I. P.; Zaitsev, I. V.; Zhdanov, A. A.; Zhmyrov, V. N.

2002-03-01

Preliminary results of the Δσ L( np) at 1.4, 1.7, 1.9 and 2.0 GeV are presented. They were obtained during the two data-taking runs at the JINR Dubna Synchrophasotron in 2001 and complete the existing data above 1.1 GeV. The data analysis is in progress. The aim of the present studies is to determine the imaginary and real parts of the np spin-dependent forward scattering amplitudes over this energy range.

Current Experiments in Particle Physics. 1996 Edition.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Galic, Hrvoje

2003-06-27

This report contains summaries of current and recent experiments in Particle Physics. Included are experiments at BEPC (Beijing), BNL, CEBAF, CERN, CESR, DESY, FNAL, Frascati, ITEP (Moscow), JINR (Dubna), KEK, LAMPF, Novosibirsk, PNPI (St. Petersburg), PSI, Saclay, Serpukhov, SLAC, and TRIUMF, and also several proton decay and solar neutrino experiments. Excluded are experiments that finished taking data before 1991. Instructions are given for the World Wide Web (WWW) searching of the computer database (maintained under the SLAC-SPIRES system) that contains the summaries.

Project Nuclotron-based Ion Collider fAcility at JINR

NASA Astrophysics Data System (ADS)

Kekelidze, V. D.; Matveev, V. A.; Meshkov, I. N.; Sorin, A. S.; Trubnikov, G. V.

2017-09-01

The project of Nuclotron-based Ion Collider fAcility (NICA) that is under development at JINR (Dubna) is presented. The general goals of the project are experimental studies of both hot and dense baryonic matter and spin physics (in collisions of polarized protons and deuterons). The first program requires providing of heavy ion collisions in the energy range of √ {{s_{NN}}} = 4-11 Gev at average luminosity of L = 1 × 1027 cm-2 s-1 for 197Au79+ nuclei. The polarized beams mode is proposed to be used in energy range of √ {{s_{NN}}} = 12-27 Gev (protons at luminosity of L ≥ 1 × 1030 cm-2 s-1. The report contains description of the facility scheme and its characteristics in heavy ion operation mode. The Collider will be equipped with two detectors—MultiPurpose Detector (MPD), which is in an active stage of construction, and Spin Physics Detector (SPD) that is in the stage of conceptual design. Fixed target experiment "Baryonic matter at Nuclotron" (BM@N) will be performed in very beginning of the project. The wide program of applied researches at NICA facility is being developed as well.

Study of the Cumulative Number Distribution of Charged Particles Produced in d12C-Interactions at 4.2 A GeV/c

NASA Astrophysics Data System (ADS)

Aslam, S. M.; Suleymanov, M. K.; Wazir, Z.; Gilani, A. R.

2018-06-01

In this paper the behavior of the cumulative number and also with maximum values of cumulative number distribution of protons, π + and π --mesons, have been studied, produced in d12C-interctions at 4.2 A GeV/c. The experimental data has been compared with ones coming from the Dubna version of the cascade model. In the analysis we have observed; four different regions in the cumulative number distributions for all charged particle and protons and the last region is corresponding to values of cumulative number greater than 1; for pions number of regions decreased to 2 for π ±-mesons but cumulative area is absent for both mesons. Cascade cannot describe satisfactorily the distributions of the cumulative protons and cumulative π -+-mesons, it gives less number for the all produced particles. In case of particles with maximum values of cumulative number cascade can describe the behavior of cumulative number distribution well. There exist some events with two cumulative particles which could not describe by the cascade dynamics. May be collective nucleon effect could be reasons of the observation two cumulative particles events.

Experimental semiotics: a review.

PubMed

Galantucci, Bruno; Garrod, Simon

2011-01-01

In the last few years a new line of research has appeared in the literature. This line of research, which may be referred to as experimental semiotics (ES; Galantucci, 2009; Galantucci and Garrod, 2010), focuses on the experimental investigation of novel forms of human communication. In this review we will (a) situate ES in its conceptual context, (b) illustrate the main varieties of studies thus far conducted by experimental semioticians, (c) illustrate three main themes of investigation which have emerged within this line of research, and (d) consider implications of this work for cognitive neuroscience.

Initial Experimental Airworthiness Certification Guidance for UAS. UAS Experimental Certification Process and Guidance

NASA Technical Reports Server (NTRS)

2005-01-01

This paper addresses the regulatory processes and requirements already in place by which an applicant might obtain experimental airworthiness certification for a civil Unmanned Aircraft System (UAS). It is more extensive and subsequent to an earlier, similar deliverable, PD007, which was an interim study of the same topic. Since few regulatory airworthiness and operating standards exist for UAS like those for traditional manned aircraft and since most UAS have historically been developed and operated under military auspices, civil use of UAS in the NAS is a new and unfamiliar challenge requiring specific and unique considerations. Experimental certification is the most basic level of FAA approval toward routine UAS operation in the NAS. The paper reviews and explains existing FAA requirements for an applicant seeking experimental airworthiness approval and details the process for submission of necessary information. It summarizes the limited purposes for which experimental aircraft may be used and addresses pertinent aspects of UAS design, construction and operation in the NAS in harmony with traditional manned aircraft. Policy IPT position is that UAS, while different from manned aircraft, can use the same initial processes to gain civil operating experience under the experimental approval. Particular note is taken of those UAS-unique characteristics which require extra attention to assure equivalent safety of operation, such as the UAS control station and sense-and-avoid. The paper also provides "best practices" guidance for UAS manufacturers and FAA personnel in two appendices. The material in Appendix A is intended to provide guidance on assuring UAS safety to FAA, and provides FAA personnel with a suggested list of items to review, with a focus on UAS unique factors, prior to issuance of an experimental airworthiness certificate. Appendix B provides an outline for a program letter which a manufacturer could use in preparing the application for an UAS

The philosophy of scientific experimentation: a review

PubMed Central

2009-01-01

Practicing and studying automated experimentation may benefit from philosophical reflection on experimental science in general. This paper reviews the relevant literature and discusses central issues in the philosophy of scientific experimentation. The first two sections present brief accounts of the rise of experimental science and of its philosophical study. The next sections discuss three central issues of scientific experimentation: the scientific and philosophical significance of intervention and production, the relationship between experimental science and technology, and the interactions between experimental and theoretical work. The concluding section identifies three issues for further research: the role of computing and, more specifically, automating, in experimental research, the nature of experimentation in the social and human sciences, and the significance of normative, including ethical, problems in experimental science. PMID:20098589

Effects of silicon cross section and neutron spectrum on the radial uniformity in neutron transmutation doping.

PubMed

Kim, Haksung; Ho Pyeon, Cheol; Lim, Jae-Yong; Misawa, Tsuyoshi

2012-01-01

The effects of silicon cross section and neutron spectrum on the radial uniformity of a Si-ingot are examined experimentally with various neutron spectrum conditions. For the cross section effect, the numerical results using silicon single crystal cross section reveal good agreements with experiments within relative difference of 6%, whereas the discrepancy is approximately 20% in free-gas cross section. For the neutron spectrum effect, the radial uniformity in hard neutron spectrum is found to be more flattening than that in soft spectrum. Copyright © 2011 Elsevier Ltd. All rights reserved.

H.J. Andrews Experimental Forest.

Treesearch

Art McKee; Pamela Druliner

1998-01-01

The H.J. Andrews Experimental Forest is a world renowned center for research and education about the ecology and management of forests and streams. Located about 50 miles (80 km) east of Eugene, Oregon, the Andrews Experimental Forest lies in the Blue River Ranger District of the Willamette National Forest. Established in 1948, the Experimental Forest is administered...

Transmutation of a heme protein.

PubMed Central

Barker, P D; Ferrer, J C; Mylrajan, M; Loehr, T M; Feng, R; Konishi, Y; Funk, W D; MacGillivray, R T; Mauk, A G

1993-01-01

Residue Asn57 of bovine liver cytochrome b5 has been replaced with a cysteine residue, and the resulting variant has been isolated from recombinant Escherichia coli as a mixture of four major species: A, BI, BII, and C. A combination of electronic spectroscopy, 1H NMR spectroscopy, resonance Raman spectroscopy, electrospray mass spectrometry, and direct electrochemistry has been used to characterize these four major cytochrome derivatives. The red form A (E(m) = -19 mV) is found to possess a heme group bound covalently through a thioether linkage involving Cys57 and the alpha carbon of the heme 4-vinyl group. Form BI has a covalently bound heme group coupled through a thioether linkage involving the beta carbon of the heme 4-vinyl group. Form BII is similar to BI except that the sulfur involved in the thioether linkage is oxidized to a sulfoxide. The green form C (E(m) = 175 mV) possesses a noncovalently bound prosthetic group with spectroscopic properties characteristic of a chlorin. A mechanism is proposed for the generation of these derivatives, and the implications of these observations for the biosynthesis of cytochrome c and naturally occurring chlorin prosthetic groups are discussed. PMID:8341666

New Insight into Nuclear Reactions in Solids

NASA Astrophysics Data System (ADS)

Miley, George H.

2003-04-01

Earlier work by the author disclosed evidence for nuclear transmutations in multi-layer thin-film Ni/Pd electrodes loaded to a high ratio of hydrogen/film metal using an electrolytic technique [1]. Non-natural isotopes abundances were found for select products. A distinctive characteristic of this and similar experiments by others is a product yield curve vs. mass with four high yield peaks distributed between low and high masses. Attempts to explain this observation have evolved around the original swimming electron layer (SEL) theory [2]. In addition, CR-39 track detector measurements have revealed low-level emission of 1.6 MeV protons and 16 MeV alpha particles from the front face of the thin film electrodes during runs [3]. Most recently Mitsubishi Corp. researchers have reported a real-time transmutation measurement using built-in XPS diagnostics where a surface layer of Sr-88 was transmuted into Mo-96 over a 200 hour run period during the diffusion of deuterium through a multi-layer thin-film Pd/CaO substrate [4]. Likewise in a companion experiment, Cs-133 was transmuted into Pr-141. These products exhibit a large deviation from natural isotopic abundance, and the characteristic signature is a mass change of 8 and charge change of 4. These various phenomena along with a preliminary theory involving SEL and orbital mixing will be presented. The objective is to provide a unified understanding of both types of experiments presented in Refs. 1 and 3. [1] G.H. Miley and J. A. Patterson, "Nuclear Transmutations in Thin-Film Nickel Coatings Undergoing Electrolysis," J. New Energy, 1, 3, 5-30 (1996). [2] H. Hora, et al., "Screening in Cold Fusion Derived from D D Reactions," Physics Ltrs. A, 175, 138-143, (1993). [3] A. Lipson, et al., "In-situ long - range alpha particles and X-ray detection in Pd thin film-cathodes during electrolysis in, Li2SO4/H2O, Bult. APS, 47, 1,Pt. II, 1219, Indianapolis, (2002). [4] Y. Iwamura, T. Itoh, et al., "Low energy nuclear reaction

Experimental Semiotics: A Review

PubMed Central

Galantucci, Bruno; Garrod, Simon

2010-01-01

In the last few years a new line of research has appeared in the literature. This line of research, which may be referred to as experimental semiotics (ES; Galantucci, 2009; Galantucci and Garrod, 2010), focuses on the experimental investigation of novel forms of human communication. In this review we will (a) situate ES in its conceptual context, (b) illustrate the main varieties of studies thus far conducted by experimental semioticians, (c) illustrate three main themes of investigation which have emerged within this line of research, and (d) consider implications of this work for cognitive neuroscience. PMID:21369364

Magnetohydrodynamic generator experimental studies

NASA Technical Reports Server (NTRS)

Pierson, E. S.

1972-01-01

The results for an experimental study of a one wavelength MHD induction generator operating on a liquid flow are presented. First the design philosophy and the experimental generator design are summarized, including a description of the flow loop and instrumentation. Next a Fourier series method of treating the fact that the magnetic flux density produced by the stator is not a pure traveling sinusoid is described and some results summarized. This approach appears to be of interest after revisions are made, but the initial results are not accurate. Finally, some of the experimental data is summarized for various methods of excitation.

Teaching experimental design.

PubMed

Fry, Derek J

2014-01-01

Awareness of poor design and published concerns over study quality stimulated the development of courses on experimental design intended to improve matters. This article describes some of the thinking behind these courses and how the topics can be presented in a variety of formats. The premises are that education in experimental design should be undertaken with an awareness of educational principles, of how adults learn, and of the particular topics in the subject that need emphasis. For those using laboratory animals, it should include ethical considerations, particularly severity issues, and accommodate learners not confident with mathematics. Basic principles, explanation of fully randomized, randomized block, and factorial designs, and discussion of how to size an experiment form the minimum set of topics. A problem-solving approach can help develop the skills of deciding what are correct experimental units and suitable controls in different experimental scenarios, identifying when an experiment has not been properly randomized or blinded, and selecting the most efficient design for particular experimental situations. Content, pace, and presentation should suit the audience and time available, and variety both within a presentation and in ways of interacting with those being taught is likely to be effective. Details are given of a three-day course based on these ideas, which has been rated informative, educational, and enjoyable, and can form a postgraduate module. It has oral presentations reinforced by group exercises and discussions based on realistic problems, and computer exercises which include some analysis. Other case studies consider a half-day format and a module for animal technicians. © The Author 2014. Published by Oxford University Press on behalf of the Institute for Laboratory Animal Research. All rights reserved. For permissions, please email: journals.permissions@oup.com.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Youinou, Gilles Jean-Michel

Neutron cross-sections characterize the way neutrons interact with matter. They are essential to most nuclear engineering projects and, even though theoretical progress has been made as far as the predictability of neutron cross-section models, measurements are still indispensable to meet tight design requirements for reduced uncertainties. Within the field of fission reactor technology, one can identify the following specializations that rely on the availability of accurate neutron cross-sections: (1) fission reactor design, (2) nuclear fuel cycles, (3) nuclear safety, (4) nuclear safeguards, (5) reactor monitoring and neutron fluence determination and (6) waste disposal and transmutation. In particular, the assessment ofmore » advanced fuel cycles requires an extensive knowledge of transuranics cross sections. Plutonium isotopes, but also americium, curium and up to californium isotope data are required with a small uncertainty in order to optimize significant features of the fuel cycle that have an impact on feasibility studies (e.g. neutron doses at fuel fabrication, decay heat in a repository, etc.). Different techniques are available to determine neutron cross sections experimentally, with the common denominator that a source of neutrons is necessary. It can either come from an accelerator that produces neutrons as a result of interactions between charged particles and a target, or it can come from a nuclear reactor. When the measurements are performed with an accelerator, they are referred to as differential since the analysis of the data provides the cross-sections for different discrete energies, i.e. σ(E i), and for the diffusion cross sections for different discrete angles. Another approach is to irradiate a very pure sample in a test reactor such as the Advanced Test Reactor (ATR) at INL and, after a given time, determine the amount of the different transmutation products. The precise characterization of the nuclide densities before and after neutron

Event-by-event pseudo-rapidity fluctuations in high energy nucleus-nucleus interactions

NASA Astrophysics Data System (ADS)

Bhattacharyya, Swarnapratim; Haiduc, Maria; Neagu, Alina Tania; Firu, Elena

2013-10-01

A detailed study of event-by-event pseudo-rapidity fluctuations in relativistic heavy-ion collisions in terms of the Φ measure and its multiplicity and target dependence has been carried out for heavy (AgBr) and light (CNO) groups of targets present in the nuclear emulsion using O16 (at an incident momentum of 4.5 A GeV/c), Ne22 (at an incident momentum of 4.1 A GeV/c), Si28 (at an incident momentum of 4.5 A GeV/c) and S32 (at an incident momentum of 4.5 A GeV/c) projectiles. For all the interactions, the total ensemble of events has been divided into three overlapping multiplicity classes depending on the number of shower particles. For all the interactions and for each multiplicity class, the Φ values are found to be greater than zero indicating the presence of strong correlation in the multiparticle production at Dubna energy. The measured Φ values are found to decrease with the increase of average multiplicity for all the interactions. The Φ values for the AgBr target are found to be greater than that for the CNO target for all the projectiles. This observation indicates the presence of stronger correlation for heavier projectiles. The experimental results have been compared with the modified FRITIOF model. It has been seen that the modified FRITIOF model cannot reproduce the experimental results.

Quasi-experimental study designs series-paper 9: collecting data from quasi-experimental studies.

PubMed

Aloe, Ariel M; Becker, Betsy Jane; Duvendack, Maren; Valentine, Jeffrey C; Shemilt, Ian; Waddington, Hugh

2017-09-01

To identify variables that must be coded when synthesizing primary studies that use quasi-experimental designs. All quasi-experimental (QE) designs. When designing a systematic review of QE studies, potential sources of heterogeneity-both theory-based and methodological-must be identified. We outline key components of inclusion criteria for syntheses of quasi-experimental studies. We provide recommendations for coding content-relevant and methodological variables and outlined the distinction between bivariate effect sizes and partial (i.e., adjusted) effect sizes. Designs used and controls used are viewed as of greatest importance. Potential sources of bias and confounding are also addressed. Careful consideration must be given to inclusion criteria and the coding of theoretical and methodological variables during the design phase of a synthesis of quasi-experimental studies. The success of the meta-regression analysis relies on the data available to the meta-analyst. Omission of critical moderator variables (i.e., effect modifiers) will undermine the conclusions of a meta-analysis. Copyright © 2017 Elsevier Inc. All rights reserved.

Children's Understanding of Experimental Contrast and Experimental Control: An Inventory for Primary School

ERIC Educational Resources Information Center

Osterhaus, Christopher; Koerber, Susanne; Sodian, Beate

2015-01-01

Experimentation skills are a central component of scientific thinking, and many studies have investigated whether and when primary-school children develop adequate experimentation strategies. However, the answers to these questions vary substantially depending on the type of task that is used: while discovery tasks, which require children to…

Experimental Evolution with Caenorhabditis Nematodes

PubMed Central

Teotónio, Henrique; Estes, Suzanne; Phillips, Patrick C.; Baer, Charles F.

2017-01-01

The hermaphroditic nematode Caenorhabditis elegans has been one of the primary model systems in biology since the 1970s, but only within the last two decades has this nematode also become a useful model for experimental evolution. Here, we outline the goals and major foci of experimental evolution with C. elegans and related species, such as C. briggsae and C. remanei, by discussing the principles of experimental design, and highlighting the strengths and limitations of Caenorhabditis as model systems. We then review three exemplars of Caenorhabditis experimental evolution studies, underlining representative evolution experiments that have addressed the: (1) maintenance of genetic variation; (2) role of natural selection during transitions from outcrossing to selfing, as well as the maintenance of mixed breeding modes during evolution; and (3) evolution of phenotypic plasticity and its role in adaptation to variable environments, including host–pathogen coevolution. We conclude by suggesting some future directions for which experimental evolution with Caenorhabditis would be particularly informative. PMID:28592504

Study of proton- and deuteron-induced spallation reactions on the long-lived fission product 93Zr at 105 MeV/nucleon in inverse kinematics

NASA Astrophysics Data System (ADS)

Kawase, Shoichiro; Nakano, Keita; Watanabe, Yukinobu; Wang, He; Otsu, Hideaki; Sakurai, Hiroyoshi; Ahn, Deuk Soon; Aikawa, Masayuki; Ando, Takashi; Araki, Shouhei; Chen, Sidong; Chiga, Nobuyuki; Doornenbal, Pieter; Fukuda, Naoki; Isobe, Tadaaki; Kawakami, Shunsuke; Kin, Tadahiro; Kondo, Yosuke; Koyama, Shunpei; Kubono, Shigeru; Maeda, Yukie; Makinaga, Ayano; Matsushita, Masafumi; Matsuzaki, Teiichiro; Michimasa, Shin'ichiro; Momiyama, Satoru; Nagamine, Shunsuke; Nakamura, Takashi; Niikura, Megumi; Ozaki, Tomoyuki; Saito, Atsumi; Saito, Takeshi; Shiga, Yoshiaki; Shikata, Mizuki; Shimizu, Yohei; Shimoura, Susumu; Sumikama, Toshiyuki; Söderström, Pär-Anders; Suzuki, Hiroshi; Takeda, Hiroyuki; Takeuchi, Satoshi; Taniuchi, Ryo; Togano, Yasuhiro; Tsubota, Jun'ichi; Uesaka, Meiko; Watanabe, Yasushi; Wimmer, Kathrin; Yamamoto, Tatsuya; Yoshida, Koichi

2017-09-01

Spallation reactions for the long-lived fission product ^{93}Zr have been studied in order to provide basic data necessary for nuclear waste transmutation. Isotopic-production cross sections via proton- and deuteron-induced spallation reactions on ^{93}Zr at 105 MeV/nucleon were measured in inverse kinematics at the RIKEN Radioactive Isotope Beam Factory. Remarkable jumps in isotopic production originating from the neutron magic number N=50 were observed in Zr and Y isotopes. The experimental results were compared to the PHITS calculations considering both the intranuclear cascade and evaporation processes, and the calculations greatly overestimated the measured production yield, corresponding to few-nucleon-removal reactions. The present data suggest that the spallation reaction is a potential candidate for the treatment of ^{93}Zr in spent nuclear fuel.

Broken symmetry and critical transport properties of random metals

PubMed Central

Phillips, J. C.

1997-01-01

Recent experimental data on the conductivity σ+(T), T → 0, on the metallic side of the metal–insulator transition in ideally random (neutron transmutation-doped) 70Ge:Ga have shown that σ+(0) ∝ (N − Nc)μ with μ = ½, confirming earlier ultra-low-temperature results for Si:P. This value is inconsistent with theoretical predictions based on diffusive classical scaling models, but it can be understood by a quantum-directed percolative filamentary amplitude model in which electronic basis states exist which have a well-defined momentum parallel but not normal to the applied electric field. The model, which is based on a new kind of broken symmetry, also explains the anomalous sign reversal of the derivative of the temperature dependence in the critical regime. PMID:11038579

Updated and revised neutron reaction data for 237Np

NASA Astrophysics Data System (ADS)

Chen, Guochang; Wang, Jimin; Cao, Wentian; Tang, Guoyou; Yu, Baosheng

2017-09-01

Nuclear data with high accuracy for minor actinides play an important role in nuclear technology applications, including reactor design and operation, fuel cycle, estimation of the amount of minor actinides in high burn-up reactors and the minor actinides transmutation. Based on the evaluated experimental data, the updated and revised evaluation of a full set of n+237Np nuclear data from 10-5 eV ˜ 20 MeV are carried out and recommended. Mainly revised quantities are neutron multiplicities from fission reaction, inelastic, fission, (n, 2n) and (n, γ) reaction cross sections as well as angular distribution and so on. The promising results are obtained when the renewal evaluated data of 237Np will be used to instead of the evaluated data in CENDL-3.1 database.

Roadmap to an Engineering-Scale Nuclear Fuel Performance & Safety Code

DOE Office of Scientific and Technical Information (OSTI.GOV)

Turner, John A; Clarno, Kevin T; Hansen, Glen A

2009-09-01

-development activities. Realizing the full benefits of this approach will likely take some time. However, it is important that the developmental activities for modeling and simulation be tightly coupled with the experimental activities to maximize feedback effects and accelerate both the experimental and analytical elements of the program toward a common objective. The close integration of modeling and simulation and experimental activities is key to developing a useful fuel performance simulation capability, providing a validated design and analysis tool, and understanding the uncertainties within the models and design process. The efforts of this project are integrally connected to the Transmutation Fuels Campaign (TFC), which maintains as a primary objective to formulate, fabricate, and qualify a transuranic-based fuel with added minor actinides for use in future fast reactors. Additional details of the TFC scope can be found in the Transmutation Fuels Campaign Execution Plan. This project is an integral component of the TFC modeling and simulation effort, and this multiyear plan borrowed liberally from the Transmutation Fuels Campaign Modeling and Simulation Roadmap. This document provides the multiyear staged development plan to develop a continuum-level Integrated Performance and Safety Code (IPSC) to predict the behavior of the fuel and cladding during normal reactor operations and anticipated transients up to the point of clad breach.« less

Wind River Experimental Forest.

Treesearch

Valerie. Rapp

2003-01-01

The Wind River Experimental Forest, known as the cradle of forest research in the Pacific Northwest, is a major center for ecological and silvicultural research in west-side Pacific Northwest forests. In the state of Washington, Wind River Experimental Forest is in the south-central area of the Gifford Pinchot National Forest, north of the Columbia River Gorge National...

Rydberg phases of Hydrogen and low energy nuclear reactions

NASA Astrophysics Data System (ADS)

Olafsson, Sveinn; Holmlid, Leif

2016-03-01

For over the last 26 years the science of cold fusion/LENR has been researched around the world with slow pace of progress. Modest quantity of excess heat and signatures of nuclear transmutation and helium production have been confirmed in experiments and theoretical work has only resulted in a large flora of inadequate theoretical scenarios. Here we review current state of research in Rydberg matter of Hydrogen that is showing strong signature of nuclear processes. In the presentation experimental behavior of Rydberg matter of hydrogen is described. An extensive collaboration effort of surface physics, catalysis, atomic physics, solid state physics, nuclear physics and quantum information is need to tackle the surprising experimental results that have so far been obtained. Rydberg matter of Hydrogen is the only known state of matter that is able to bring huge collection of protons to so short distances and for so long time that tunneling becomes a reasonable process for making low energy nuclear reactions. Nuclear quantum entanglement can also become realistic process at theses conditions.

Silver (Ag) Transport Mechanisms in TRISO Coated Particles: A Critical Review

DOE Office of Scientific and Technical Information (OSTI.GOV)

IJ van Rooyen; ML Dunzik-Gougar; PM van Rooyen

2014-05-01

Transport of 110mAg in the intact SiC layer of TRISO coated particles has been studied for approximately 30 years without arriving at a satisfactory explanation of the transport mechanism. In this paper the possible mechanisms postulated in previous experimental studies, both in-reactor and out-of reactor research environment studies are critically reviewed and of particular interest are relevance to very high temperature gas reactor operating and accident conditions. Among the factors thought to influence Ag transport are grain boundary stoichiometry, SiC grain size and shape, the presence of free silicon, nano-cracks, thermal decomposition, palladium attack, transmutation products, layer thinning and coatedmore » particle shape. Additionally new insight to nature and location of fission products has been gained via recent post irradiation electron microscopy examination of TRISO coated particles from the DOE’s fuel development program. The combined effect of critical review and new analyses indicates a direction for investigating possible the Ag transport mechanism including the confidence level with which these mechanisms may be experimentally verified.« less

Silver (Ag) Transport Mechanisms in TRISO coated particles: A Critical Review

DOE Office of Scientific and Technical Information (OSTI.GOV)

I J van Rooyen; J H Neethling; J A A Engelbrecht

2012-10-01

Transport of 110mAg in the intact SiC layer of TRISO coated particles has been studied for approximately 30 years without arriving at a satisfactory explanation of the transport mechanism. In this paper the possible mechanisms postulated in previous experimental studies, both in-reactor and out-of reactor research environment studies are critically reviewed and of particular interest are relevance to very high temperature gas reactor operating and accident conditions. Among the factors thought to influence Ag transport are grain boundary stoichiometry, SiC grain size and shape, the presence of free silicon, nano-cracks, thermal decomposition, palladium attack, transmutation products, layer thinning and coatedmore » particle shape. Additionally new insight to nature and location of fission products has been gained via recent post irradiation electron microscopy examination of TRISO coated particles from the DOE’s fuel development program. The combined effect of critical review and new analyses indicates a direction for investigating possible the Ag transport mechanism including the confidence level with which these mechanisms may be experimentally verified.« less

The '3Is' of animal experimentation.

PubMed

2012-05-29

Animal experimentation in scientific research is a good thing: important, increasing and often irreplaceable. Careful experimental design and reporting are at least as important as attention to welfare in ensuring that the knowledge we gain justifies using live animals as experimental tools.

14 CFR 21.275 - Experimental certificates.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Experimental certificates. 21.275 Section... CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Delegation Option Authorization Procedures § 21.275 Experimental certificates. (a) The manufacturer shall, before issuing an experimental certificate, obtain from the...

14 CFR 21.275 - Experimental certificates.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Experimental certificates. 21.275 Section... CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Delegation Option Authorization Procedures § 21.275 Experimental certificates. (a) The manufacturer shall, before issuing an experimental certificate, obtain from the...

50 CFR 648.12 - Experimental fishing.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Experimental fishing. 648.12 Section 648... Experimental fishing. The Regional Administrator may exempt any person or vessel from the requirements of... red crab), N (tilefish), and O (skates) of this part for the conduct of experimental fishing...

50 CFR 648.12 - Experimental fishing.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Experimental fishing. 648.12 Section 648... Experimental fishing. The Regional Administrator may exempt any person or vessel from the requirements of... red crab), N (tilefish), and O (skates) of this part for the conduct of experimental fishing...

50 CFR 648.12 - Experimental fishing.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Experimental fishing. 648.12 Section 648... Experimental fishing. The Regional Administrator may exempt any person or vessel from the requirements of... red crab), N (tilefish), and O (skates) of this part for the conduct of experimental fishing...

50 CFR 648.12 - Experimental fishing.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Experimental fishing. 648.12 Section 648... Experimental fishing. The Regional Administrator may exempt any person or vessel from the requirements of... red crab), N (tilefish), and O (skates) of this part for the conduct of experimental fishing...

Impact of the deployment schedule of fast breeding reactors in the frame of French act for nuclear materials and radioactive waste management

DOE Office of Scientific and Technical Information (OSTI.GOV)

Le Mer, J.; Garzenne, C.; Lemasson, D.

In the frame of the French Act of June 28, 2006 on 'a sustainable management of nuclear materials and radioactive waste' EDF R and D assesses various research scenarios of transition between the actual French fleet and a Generation IV fleet with a closed fuel cycle where plutonium is multi-recycled. The basic scenarios simulate a deployment of 60 GWe of Sodium-cooled Fast Reactors (SFRs) in two steps: one third from 2040 to 2050 and the rest from 2080 to 2100 (scenarios 2040). These research scenarios assume that SFR technology will be ready for industrial deployment in 2040. One of themore » many sensitivity analyses that EDF, as a nuclear power plant operator, must evaluate is the impact of a delay of SFR technology in terms of uranium consumptions, plutonium needs and fuel cycle utilities gauging. The sensitivity scenarios use the same assumptions as scenarios 2040 but they simulate a different transition phase: SFRs are deployed in one step between 2080 and 2110 (scenarios 2080). As the French Act states to conduct research on minor actinides (MA) management, we studied different options for 2040 and 2080 scenarios: no MA transmutation, americium transmutation in heterogeneous mode based on americium Bearing Blankets (AmBB) in SFRs and all MA transmutation in heterogeneous mode based on MA Bearing Blankets (MABB). Moreover, we studied multiple parameters that could impact the deployment of these reactors (SFR load factor, increase of the use of MOX in Light Water Reactors, increase of the cooling time in spent nuclear fuel storage...). Each scenario has been computed with the EDF R and D fuel cycle simulation code TIRELIRE-STRATEGIE and optimized to meet various fuel cycle constraints such as using the reprocessing facility with long period of constant capacity, keeping the temporary stored mass of plutonium and MA under imposed limits, recycling older assemblies first... These research scenarios show that the transition from the current PWR fleet to an

50 CFR 648.12 - Experimental fishing.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 10 2011-10-01 2011-10-01 false Experimental fishing. 648.12 Section 648... Experimental fishing. Link to an amendment published at 76 FR 60649, Sept. 29, 2011. The Regional Administrator... part for the conduct of experimental fishing beneficial to the management of the resources or fishery...

27 CFR 40.232 - Experimental purposes.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2012-04-01 2011-04-01 true Experimental purposes. 40... Products § 40.232 Experimental purposes. A manufacturer of tobacco products may use tobacco products for experimental purposes without determination and payment of tax as set forth in this section. (a) What are...

Design and simulation of ion optics for ion sources for production of singly charged ions

NASA Astrophysics Data System (ADS)

Zelenak, A.; Bogomolov, S. L.

2004-05-01

During the last 2 years different types of the singly charged ion sources were developed for FLNR (JINR) new projects such as Dubna radioactive ion beams, (Phase I and Phase II), the production of the tritium ion beam and the MASHA mass separator. The ion optics simulations for 2.45 GHz electron cyclotron resonance source, rf source, and the plasma ion source were performed. In this article the design and simulation results of the optics of new ion sources are presented. The results of simulation are compared with measurements obtained during the experiments.

Multiplicities of secondaries in interactions of 1.8 GeV/nucleon Fe-56 nuclei with photoemulsion and the cascade evaporation model

NASA Technical Reports Server (NTRS)

Dudkin, V. E; Kovalev, E. E.; Nefedov, N. A.; Antonchik, V. A.; Bogdanov, S. D.; Ostroumov, V. I.; Crawford, H. J.; Benton, E. V.

1995-01-01

A nuclear photographic emulsion method was used to study the charge-state, ionization, and angular characteristics of secondaries produced in inelastic interactions of Fe-56 nuclei at 1.8 GeV/nucleon with H, CNO, and AgBr nuclei. The data obtained are compared with the results of calculations made in terms of the Dubna version of the cascade evaporation model (DCM). The DCM has been shown to satisfactorily describe most of the interaction characteristics for two nuclei in the studied reactions. At the same time, quantitative differences are observed in some cases.

Track reconstruction and particle identification developments for a study of event-by-event fluctuations in heavy ion collisions at NICA

NASA Astrophysics Data System (ADS)

Mudrokh, A. A.; Zinchenko, A. I.

2017-01-01

A Monte Carlo simulation of heavy ion collisions (Au+Au) has been performed at MPD (Multi Purpose Detector) at NICA (Dubna) for a study of the possible critical point in the phase diagram of the hot nuclear matter. The simulation took into account real detector effects with as many details as possible to properly describe the apparatus response. Particle identification (PID) has been tuned to account for modifications in track reconstruction. Some results on hadron identification in the TPC and TOF (Time Of Flight) detectors with realistically simulated response have been also obtained.

Experimental intrauterine growth retardation.

PubMed

van Marthens, E; Harel, S; Zamenshof, S

1975-01-01

The effects of experimental intrauterine growth retardation on subsequent fetal development, especially with respect to brain development, were studied in a new animal model. The rabbit was chosen since it has a perinatal pattern of brain development similar to that of the human. Experimental ischemia was induced during the last trimester by ligation of spiral arterioles and the differential effects on fetal development at term (30th gestational day) are reported. Specific brain regions were examined for wet weight, total cell number (DNA) and total protein content. Highly significant decreases in all these parameters were found in both the cortex and cerebellum following experimental intrauterine growth retardation; these two organs were differentially affected. The prospects and advantages of using this animal model for the study of the postnatal "catch-up growth" are discussed.

Experimenter bias and subliminal perception

ERIC Educational Resources Information Center

Barber, Paul J.; Rushton, J. Philippe

1975-01-01

It has been suggested that subliminal perception phenomena may be in part due to experimenter bias effects. Two studies that obtained positive evidence of subliminal perception were therefore replicated with experimenters tested under blind and not blind conditions. (Editor)

Threats to the Internal Validity of Experimental and Quasi-Experimental Research in Healthcare.

PubMed

Flannelly, Kevin J; Flannelly, Laura T; Jankowski, Katherine R B

2018-01-01

The article defines, describes, and discusses the seven threats to the internal validity of experiments discussed by Donald T. Campbell in his classic 1957 article: history, maturation, testing, instrument decay, statistical regression, selection, and mortality. These concepts are said to be threats to the internal validity of experiments because they pose alternate explanations for the apparent causal relationship between the independent variable and dependent variable of an experiment if they are not adequately controlled. A series of simple diagrams illustrate three pre-experimental designs and three true experimental designs discussed by Campbell in 1957 and several quasi-experimental designs described in his book written with Julian C. Stanley in 1966. The current article explains why each design controls for or fails to control for these seven threats to internal validity.

Statistical Model Analysis of (n,p) Cross Sections and Average Energy For Fission Neutron Spectrum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Odsuren, M.; Khuukhenkhuu, G.

2011-06-28

Investigation of charged particle emission reaction cross sections for fast neutrons is important to both nuclear reactor technology and the understanding of nuclear reaction mechanisms. In particular, the study of (n,p) cross sections is necessary to estimate radiation damage due to hydrogen production, nuclear heating and transmutations in the structural materials of fission and fusion reactors. On the other hand, it is often necessary in practice to evaluate the neutron cross sections of the nuclides for which no experimental data are available.Because of this, we carried out the systematical analysis of known experimental (n,p) and (n,a) cross sections for fastmore » neutrons and observed a systematical regularity in the wide energy interval of 6-20 MeV and for broad mass range of target nuclei. To explain this effect using the compound, pre-equilibrium and direct reaction mechanisms some formulae were deduced. In this paper, in the framework of the statistical model known experimental (n,p) cross sections averaged over the thermal fission neutron spectrum of U-235 are analyzed. It was shown that the experimental data are satisfactorily described by the statistical model. Also, in the case of (n,p) cross sections the effective average neutron energy for fission spectrum of U-235 was found to be around 3 MeV.« less

Porphyromonas gingivalis Peptidylarginine Deiminase, a Key Contributor in the Pathogenesis of Experimental Periodontal Disease and Experimental Arthritis

PubMed Central

Gully, Neville; Bright, Richard; Marino, Victor; Marchant, Ceilidh; Cantley, Melissa; Haynes, David; Butler, Catherine; Dashper, Stuart; Reynolds, Eric; Bartold, Mark

2014-01-01

Objectives To investigate the suggested role of Porphyromonas gingivalis peptidylarginine deiminase (PAD) in the relationship between the aetiology of periodontal disease and experimentally induced arthritis and the possible association between these two conditions. Methods A genetically modified PAD-deficient strain of P. gingivalis W50 was produced. The effect of this strain, compared to the wild type, in an established murine model for experimental periodontitis and experimental arthritis was assessed. Experimental periodontitis was induced following oral inoculation with the PAD-deficient and wild type strains of P. gingivalis. Experimental arthritis was induced via the collagen antibody induction process and was monitored by assessment of paw swelling and micro-CT analysis of the radio-carpal joints. Experimental periodontitis was monitored by micro CT scans of the mandible and histological assessment of the periodontal tissues around the mandibular molars. Serum levels of anti-citrullinated protein antibodies (ACPA) and P. gingivalis were assessed by ELISA. Results The development of experimental periodontitis was significantly reduced in the presence of the PAD-deficient P. gingivalis strain. When experimental arthritis was induced in the presence of the PAD-deficient strain there was less paw swelling, less erosive bone damage to the joints and reduced serum ACPA levels when compared to the wild type P. gingivalis inoculated group. Conclusion This study has demonstrated that a PAD-deficient strain of P. gingivalis was associated with significantly reduced periodontal inflammation. In addition the extent of experimental arthritis was significantly reduced in animals exposed to prior induction of periodontal disease through oral inoculation of the PAD-deficient strain versus the wild type. This adds further evidence to the potential role for P. gingivalis and its PAD in the pathogenesis of periodontitis and exacerbation of arthritis. Further studies are now

30 CFR 785.13 - Experimental practices mining.

Code of Federal Regulations, 2012 CFR

2012-07-01

... practice shall contain descriptions, maps, plans, and data which show— (1) The nature of the experimental....S. Department of Agriculture, Soil Conservation Service. (f) Each person undertaking an experimental...

30 CFR 785.13 - Experimental practices mining.

Code of Federal Regulations, 2014 CFR

2014-07-01

... practice shall contain descriptions, maps, plans, and data which show— (1) The nature of the experimental....S. Department of Agriculture, Soil Conservation Service. (f) Each person undertaking an experimental...

30 CFR 785.13 - Experimental practices mining.

Code of Federal Regulations, 2013 CFR

2013-07-01

... practice shall contain descriptions, maps, plans, and data which show— (1) The nature of the experimental....S. Department of Agriculture, Soil Conservation Service. (f) Each person undertaking an experimental...

True and Quasi-Experimental Designs. ERIC/AE Digest.

ERIC Educational Resources Information Center

Gribbons, Barry; Herman, Joan

Among the different types of experimental design are two general categories: true experimental designs and quasi- experimental designs. True experimental designs include more than one purposively created group, common measured outcomes, and random assignment. Quasi-experimental designs are commonly used when random assignment is not practical or…

Semi-experimental equilibrium structure of pyrazinamide from gas-phase electron diffraction. How much experimental is it?

NASA Astrophysics Data System (ADS)

Tikhonov, Denis S.; Vishnevskiy, Yury V.; Rykov, Anatolii N.; Grikina, Olga E.; Khaikin, Leonid S.

2017-03-01

A semi-experimental equilibrium structure of free molecules of pyrazinamide has been determined for the first time using gas electron diffraction method. The refinement was carried using regularization of geometry by calculated quantum chemical parameters. It is discussed to which extent is the final structure experimental. A numerical approach for estimation of the amount of experimental information in the refined parameters is suggested. The following values of selected internuclear distances were determined (values are in Å with 1σ in the parentheses): re(Cpyrazine-Cpyrazine)av = 1.397(2), re(Npyrazine-Cpyrazine)av = 1.332(3), re(Cpyrazine-Camide) = 1.493(1), re(Namide-Camide) = 1.335(2), re(Oamide-Camide) = 1.219(1). The given standard deviations represent pure experimental uncertainties without the influence of regularization.

Optimal Objective-Based Experimental Design for Uncertain Dynamical Gene Networks with Experimental Error.

PubMed

Mohsenizadeh, Daniel N; Dehghannasiri, Roozbeh; Dougherty, Edward R

2018-01-01

In systems biology, network models are often used to study interactions among cellular components, a salient aim being to develop drugs and therapeutic mechanisms to change the dynamical behavior of the network to avoid undesirable phenotypes. Owing to limited knowledge, model uncertainty is commonplace and network dynamics can be updated in different ways, thereby giving multiple dynamic trajectories, that is, dynamics uncertainty. In this manuscript, we propose an experimental design method that can effectively reduce the dynamics uncertainty and improve performance in an interaction-based network. Both dynamics uncertainty and experimental error are quantified with respect to the modeling objective, herein, therapeutic intervention. The aim of experimental design is to select among a set of candidate experiments the experiment whose outcome, when applied to the network model, maximally reduces the dynamics uncertainty pertinent to the intervention objective.

Neutron transport-burnup code MCORGS and its application in fusion fission hybrid blanket conceptual research

NASA Astrophysics Data System (ADS)

Shi, Xue-Ming; Peng, Xian-Jue

2016-09-01

Fusion science and technology has made progress in the last decades. However, commercialization of fusion reactors still faces challenges relating to higher fusion energy gain, irradiation-resistant material, and tritium self-sufficiency. Fusion Fission Hybrid Reactors (FFHR) can be introduced to accelerate the early application of fusion energy. Traditionally, FFHRs have been classified as either breeders or transmuters. Both need partition of plutonium from spent fuel, which will pose nuclear proliferation risks. A conceptual design of a Fusion Fission Hybrid Reactor for Energy (FFHR-E), which can make full use of natural uranium with lower nuclear proliferation risk, is presented. The fusion core parameters are similar to those of the International Thermonuclear Experimental Reactor. An alloy of natural uranium and zirconium is adopted in the fission blanket, which is cooled by light water. In order to model blanket burnup problems, a linkage code MCORGS, which couples MCNP4B and ORIGEN-S, is developed and validated through several typical benchmarks. The average blanket energy Multiplication and Tritium Breeding Ratio can be maintained at 10 and 1.15 respectively over tens of years of continuous irradiation. If simple reprocessing without separation of plutonium from uranium is adopted every few years, FFHR-E can achieve better neutronic performance. MCORGS has also been used to analyze the ultra-deep burnup model of Laser Inertial Confinement Fusion Fission Energy (LIFE) from LLNL, and a new blanket design that uses Pb instead of Be as the neutron multiplier is proposed. In addition, MCORGS has been used to simulate the fluid transmuter model of the In-Zinerater from Sandia. A brief comparison of LIFE, In-Zinerater, and FFHR-E will be given.

Design approaches to experimental mediation☆

PubMed Central

Pirlott, Angela G.; MacKinnon, David P.

2016-01-01

Identifying causal mechanisms has become a cornerstone of experimental social psychology, and editors in top social psychology journals champion the use of mediation methods, particularly innovative ones when possible (e.g. Halberstadt, 2010, Smith, 2012). Commonly, studies in experimental social psychology randomly assign participants to levels of the independent variable and measure the mediating and dependent variables, and the mediator is assumed to causally affect the dependent variable. However, participants are not randomly assigned to levels of the mediating variable(s), i.e., the relationship between the mediating and dependent variables is correlational. Although researchers likely know that correlational studies pose a risk of confounding, this problem seems forgotten when thinking about experimental designs randomly assigning participants to levels of the independent variable and measuring the mediator (i.e., “measurement-of-mediation” designs). Experimentally manipulating the mediator provides an approach to solving these problems, yet these methods contain their own set of challenges (e.g., Bullock, Green, & Ha, 2010). We describe types of experimental manipulations targeting the mediator (manipulations demonstrating a causal effect of the mediator on the dependent variable and manipulations targeting the strength of the causal effect of the mediator) and types of experimental designs (double randomization, concurrent double randomization, and parallel), provide published examples of the designs, and discuss the strengths and challenges of each design. Therefore, the goals of this paper include providing a practical guide to manipulation-of-mediator designs in light of their challenges and encouraging researchers to use more rigorous approaches to mediation because manipulation-of-mediator designs strengthen the ability to infer causality of the mediating variable on the dependent variable. PMID:27570259

Design approaches to experimental mediation.

PubMed

Pirlott, Angela G; MacKinnon, David P

2016-09-01

Identifying causal mechanisms has become a cornerstone of experimental social psychology, and editors in top social psychology journals champion the use of mediation methods, particularly innovative ones when possible (e.g. Halberstadt, 2010, Smith, 2012). Commonly, studies in experimental social psychology randomly assign participants to levels of the independent variable and measure the mediating and dependent variables, and the mediator is assumed to causally affect the dependent variable. However, participants are not randomly assigned to levels of the mediating variable(s), i.e., the relationship between the mediating and dependent variables is correlational. Although researchers likely know that correlational studies pose a risk of confounding, this problem seems forgotten when thinking about experimental designs randomly assigning participants to levels of the independent variable and measuring the mediator (i.e., "measurement-of-mediation" designs). Experimentally manipulating the mediator provides an approach to solving these problems, yet these methods contain their own set of challenges (e.g., Bullock, Green, & Ha, 2010). We describe types of experimental manipulations targeting the mediator (manipulations demonstrating a causal effect of the mediator on the dependent variable and manipulations targeting the strength of the causal effect of the mediator) and types of experimental designs (double randomization, concurrent double randomization, and parallel), provide published examples of the designs, and discuss the strengths and challenges of each design. Therefore, the goals of this paper include providing a practical guide to manipulation-of-mediator designs in light of their challenges and encouraging researchers to use more rigorous approaches to mediation because manipulation-of-mediator designs strengthen the ability to infer causality of the mediating variable on the dependent variable.

Neutron cross section measurements at n-TOF for ADS related studies

NASA Astrophysics Data System (ADS)

Mastinu, P. F.; Abbondanno, U.; Aerts, G.; Álvarez, H.; Alvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Assimakopoulos, P.; Audouin, L.; Badurek, G.; Bustreo, N.; aumann, P.; vá, F. Be; Berthoumieux, E.; Calviño, F.; Cano-Ott, D.; Capote, R.; Carrillo de Albornoz, A.; Cennini, P.; Chepel, V.; Chiaveri, E.; Colonna, N.; Cortes, G.; Couture, A.; Cox, J.; Dahlfors, M.; David, S.; Dillmann, I.; Dolfini, R.; Domingo-Pardo, C.; Dridi, W.; Duran, I.; Eleftheriadis, C.; Embid-Segura, M.; Ferrant, L.; Ferrari, A.; Ferreira-Marques, R.; itzpatrick, L.; Frais-Kölbl, H.; Fujii, K.; Furman, W.; Guerrero, C.; Goncalves, I.; Gallino, R.; Gonzalez-Romero, E.; Goverdovski, A.; Gramegna, F.; Griesmayer, E.; Gunsing, F.; Haas, B.; Haight, R.; Heil, M.; Herrera-Martinez, A.; Igashira, M.; Isaev, S.; Jericha, E.; Kadi, Y.; Käppeler, F.; Karamanis, D.; Karadimos, D.; Kerveno, M.; Ketlerov, V.; Koehler, P.; Konovalov, V.; Kossionides, E.; Krti ka, M.; Lamboudis, C.; Leeb, H.; Lindote, A.; Lopes, I.; Lozano, M.; Lukic, S.; Marganiec, J.; Marques, L.; Marrone, S.; Massimi, C.; Mengoni, A.; Milazzo, P. M.; Moreau, C.; Mosconi, M.; Neves, F.; Oberhummer, H.; O'Brien, S.; Oshima, M.; Pancin, J.; Papachristodoulou, C.; Papadopoulos, C.; Paradela, C.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perrot, L.; Plag, R.; Plompen, A.; Plukis, A.; Poch, A.; Pretel, C.; Quesada, J.; Rauscher, T.; Reifarth, R.; Rosetti, M.; Rubbia, C.; Rudolf, G.; Rullhusen, P.; Salgado, J.; Sarchiapone, L.; Savvidis, I.; Stephan, C.; Tagliente, G.; Tain, J. L.; Tassan-Got, L.; Tavora, L.; Terlizzi, R.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vincente, M. C.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Walter, S.; Wendler, H.; Wiescherand, M.; Wisshak, K.

2006-05-01

A neutron Time-of-Flight facility (n_TOF) is available at CERN since 2001. The innovative features of the neutron beam, in particular the high instantaneous flux, the wide energy range, the high resolution and the low background, make this facility unique for measurements of neutron induced reactions relevant to the field of Emerging Nuclear Technologies, as well as to Nuclear Astrophysics and Fundamental Nuclear Physics. The scientific motivations that have led to the construction of this new facility are here presented. The main characteristics of the n_TOF neutron beam are described, together with the features of the experimental apparata used for cross-section measurements. The main results of the first measurement campaigns are presented. Preliminary results of capture cross-section measurements of minor actinides, important to ADS project for nuclear waste transmutation, are finally discussed.

Mapping of the thermal neutron distribution in the lead block assembly of the PS-211 experiment at CERN, using thermoluminescence and nuclear track detectors.

PubMed

Savvidis, E; Eleftheriadis, C A; Kitis, G

2002-01-01

The main purpose of the TARC (Transmutation by Adiabatic Resonance Crossing) experiment (PS-211), was to demonstrate the possibility to destroy efficiently Long-Lived Fission Fragments (LLFF) in Accelerator Driven Systems (ADS). The experimental set-up which consisted of a lead block with dimensions 3.3 x 3.3 x 3 m3, was installed in a CERN Proton Synchrotron (PS) beam line. The proton beam at 2.5 GeV/c and 3.5 GeV/c, was incident in the centre of the lead block assembly producing neutrons via spallation reactions. In this study, neutron flux measurements are presented in the lead block assembly using thermoluminescence and nuclear track detectors. The results are in good agreement with Monte Carlo calculations as well as with the results of the other methods used in the framework of the TARC experiment.

Calculation and analysis of cross-sections for p+184W reactions up to 200 MeV

NASA Astrophysics Data System (ADS)

Sun, Jian-Ping; Zhang, Zheng-Jun; Han, Yin-Lu

2015-08-01

A set of optimal proton optical potential parameters for p+ 184W reactions are obtained at incident proton energy up to 250 MeV. Based on these parameters, the reaction cross-sections, elastic scattering angular distributions, energy spectra and double differential cross sections of proton-induced reactions on 184W are calculated and analyzed by using theoretical models which integrate the optical model, distorted Born wave approximation theory, intra-nuclear cascade model, exciton model, Hauser-Feshbach theory and evaporation model. The calculated results are compared with existing experimental data and good agreement is achieved. Supported by National Basic Research Program of China, Technology Research of Accelerator Driven Sub-critical System for Nuclear Waste Transmutation (2007CB209903) and Strategic Priority Research Program of Chinese Academy of Sciences, Thorium Molten Salt Reactor Nuclear Energy System (XDA02010100)

Trends in animal experimentation.

PubMed

Monteiro, Rosangela; Brandau, Ricardo; Gomes, Walter J; Braile, Domingo M

2009-01-01

The search of the understanding of etiological factors, mechanisms and treatment of the diseases has been taking to the development of several animal models in the last decades. To discuss aspects related to animal models of experimentation, animal choice and current trends in this field in our country. In addition, this study evaluated the frequency of experimental articles in medical journals. Five Brazilian journals indexed by LILACS, SciELO, MEDLINE, and recently incorporate for Institute for Scientific Information Journal of Citation Reports were analyzed. All the papers published in those journals, between 2007 and 2008, that used animal models, were selected based on the abstracts. Of the total of 832 articles published in the period, 92 (11.1%) experimentation papers were selected. The number of experimental articles ranged from 5.2% to 17.9% of the global content of the journal. In the instructions to the authors, four (80%) journals presented explicit reference to the ethical principles in the conduction of studies with animals. The induced animal models represented 100% of the articles analyzed in this study. The rat was the most employed animal in the analyzed articles (78.3%). The present study can contribute, supplying subsidies for adoption of future editorials policies regarding the publication of animal research papers in Brazilian Journal of Cardiovascular Surgery.

Experimental Methodology in English Teaching and Learning: Method Features, Validity Issues, and Embedded Experimental Design

ERIC Educational Resources Information Center

Lee, Jang Ho

2012-01-01

Experimental methods have played a significant role in the growth of English teaching and learning studies. The paper presented here outlines basic features of experimental design, including the manipulation of independent variables, the role and practicality of randomised controlled trials (RCTs) in educational research, and alternative methods…

Preclinical electrogastrography in experimental pigs

PubMed Central

Květina, Jaroslav; Varayil, Jithinraj Edakkanambeth; Ali, Shahzad Marghoob; Kuneš, Martin; Bureš, Jan; Tachecí, Ilja; Rejchrt, Stanislav; Kopáčová, Marcela

2010-01-01

Surface electrogastrography (EGG) is a non-invasive means of recording gastric myoelectric activity or slow waves from cutaneous leads placed over the stomach. This paper provides a comprehensive review of preclinical EGG. Our group recently set up and worked out the methods for EGG in experimental pigs. We gained our initial experience in the use of EGG in assessment of porcine gastric myoelectric activity after volume challenge and after intragastric administration of itopride and erythromycin. The mean dominant frequency in pigs is comparable with that found in humans. EGG in experimental pigs is feasible. Experimental EGG is an important basis for further preclinical projects in pharmacology and toxicology. PMID:21217873

Mainstreaming Caenorhabditis elegans in experimental evolution.

PubMed

Gray, Jeremy C; Cutter, Asher D

2014-03-07

Experimental evolution provides a powerful manipulative tool for probing evolutionary process and mechanism. As this approach to hypothesis testing has taken purchase in biology, so too has the number of experimental systems that use it, each with its own unique strengths and weaknesses. The depth of biological knowledge about Caenorhabditis nematodes, combined with their laboratory tractability, positions them well for exploiting experimental evolution in animal systems to understand deep questions in evolution and ecology, as well as in molecular genetics and systems biology. To date, Caenorhabditis elegans and related species have proved themselves in experimental evolution studies of the process of mutation, host-pathogen coevolution, mating system evolution and life-history theory. Yet these organisms are not broadly recognized for their utility for evolution experiments and remain underexploited. Here, we outline this experimental evolution work undertaken so far in Caenorhabditis, detail simple methodological tricks that can be exploited and identify research areas that are ripe for future discovery.

Experimental Mathematics and Computational Statistics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bailey, David H.; Borwein, Jonathan M.

2009-04-30

The field of statistics has long been noted for techniques to detect patterns and regularities in numerical data. In this article we explore connections between statistics and the emerging field of 'experimental mathematics'. These includes both applications of experimental mathematics in statistics, as well as statistical methods applied to computational mathematics.

Experimental Learning Enhancing Improvisation Skills

ERIC Educational Resources Information Center

Pereira Christopoulos, Tania; Wilner, Adriana; Trindade Bestetti, Maria Luisa

2016-01-01

Purpose: This study aims to present improvisation training and experimentation as an alternative method to deal with unexpected events in which structured processes do not seem to work. Design/Methodology/Approach: Based on the literature of sensemaking and improvisation, the study designs a framework and process model of experimental learning…

High Throughput Experimental Materials Database

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zakutayev, Andriy; Perkins, John; Schwarting, Marcus

The mission of the High Throughput Experimental Materials Database (HTEM DB) is to enable discovery of new materials with useful properties by releasing large amounts of high-quality experimental data to public. The HTEM DB contains information about materials obtained from high-throughput experiments at the National Renewable Energy Laboratory (NREL).

Assessing Pupils' Skills in Experimentation

ERIC Educational Resources Information Center

Hammann, Marcus; Phan, Thi Thanh Hoi; Ehmer, Maike; Grimm, Tobias

2008-01-01

This study is concerned with different forms of assessment of pupils' skills in experimentation. The findings of three studies are reported. Study 1 investigates whether it is possible to develop reliable multiple-choice tests for the skills of forming hypotheses, designing experiments and analysing experimental data. Study 2 compares scores from…

Experimental scattershot boson sampling

PubMed Central

Bentivegna, Marco; Spagnolo, Nicolò; Vitelli, Chiara; Flamini, Fulvio; Viggianiello, Niko; Latmiral, Ludovico; Mataloni, Paolo; Brod, Daniel J.; Galvão, Ernesto F.; Crespi, Andrea; Ramponi, Roberta; Osellame, Roberto; Sciarrino, Fabio

2015-01-01

Boson sampling is a computational task strongly believed to be hard for classical computers, but efficiently solvable by orchestrated bosonic interference in a specialized quantum computer. Current experimental schemes, however, are still insufficient for a convincing demonstration of the advantage of quantum over classical computation. A new variation of this task, scattershot boson sampling, leads to an exponential increase in speed of the quantum device, using a larger number of photon sources based on parametric down-conversion. This is achieved by having multiple heralded single photons being sent, shot by shot, into different random input ports of the interferometer. We report the first scattershot boson sampling experiments, where six different photon-pair sources are coupled to integrated photonic circuits. We use recently proposed statistical tools to analyze our experimental data, providing strong evidence that our photonic quantum simulator works as expected. This approach represents an important leap toward a convincing experimental demonstration of the quantum computational supremacy. PMID:26601164

Experimental scattershot boson sampling.

PubMed

Bentivegna, Marco; Spagnolo, Nicolò; Vitelli, Chiara; Flamini, Fulvio; Viggianiello, Niko; Latmiral, Ludovico; Mataloni, Paolo; Brod, Daniel J; Galvão, Ernesto F; Crespi, Andrea; Ramponi, Roberta; Osellame, Roberto; Sciarrino, Fabio

2015-04-01

Boson sampling is a computational task strongly believed to be hard for classical computers, but efficiently solvable by orchestrated bosonic interference in a specialized quantum computer. Current experimental schemes, however, are still insufficient for a convincing demonstration of the advantage of quantum over classical computation. A new variation of this task, scattershot boson sampling, leads to an exponential increase in speed of the quantum device, using a larger number of photon sources based on parametric down-conversion. This is achieved by having multiple heralded single photons being sent, shot by shot, into different random input ports of the interferometer. We report the first scattershot boson sampling experiments, where six different photon-pair sources are coupled to integrated photonic circuits. We use recently proposed statistical tools to analyze our experimental data, providing strong evidence that our photonic quantum simulator works as expected. This approach represents an important leap toward a convincing experimental demonstration of the quantum computational supremacy.

MEASUREMENT AND PRECISION, EXPERIMENTAL VERSION.

ERIC Educational Resources Information Center

Harvard Univ., Cambridge, MA. Harvard Project Physics.

THIS DOCUMENT IS AN EXPERIMENTAL VERSION OF A PROGRAMED TEXT ON MEASUREMENT AND PRECISION. PART I CONTAINS 24 FRAMES DEALING WITH PRECISION AND SIGNIFICANT FIGURES ENCOUNTERED IN VARIOUS MATHEMATICAL COMPUTATIONS AND MEASUREMENTS. PART II BEGINS WITH A BRIEF SECTION ON EXPERIMENTAL DATA, COVERING SUCH POINTS AS (1) ESTABLISHING THE ZERO POINT, (2)…

Rapidity distributions of hadrons in the HydHSD hybrid model

NASA Astrophysics Data System (ADS)

Khvorostukhin, A. S.; Toneev, V. D.

2017-03-01

A multistage hybrid model intended for describing heavy-ion interactions in the energy region of the NICA collider under construction in Dubna is proposed. The model combines the initial, fast, interaction stage described by the model of hadron string dynamics (HSD) and the subsequent evolution that the expanding system formed at the first stage experiences at the second stage and which one treats on the basis of ideal hydrodynamics; after the completion of the second stage, the particles involved may still undergo rescattering (third interaction stage). The model admits three freeze-out scenarios: isochronous, isothermal, and isoenergetic. Generally, the HydHSD hybrid model developed in the present study provides fairly good agreement with available experimental data on proton rapidity spectra. It is shown that, within this hybrid model, the two-humped structure of proton rapidity distributions can be obtained either by increasing the freeze-out temperature and energy density or by more lately going over to the hydrodynamic stage. Although the proposed hybrid model reproduces rapidity spectra of protons, it is unable to describe rapidity distributions of pions, systematically underestimating their yield. It is necessary to refine the model by including viscosity effects at the hydrodynamic stage of evolution of the system and by considering in more detail the third interaction stage.

Access to Experimental Cancer Drugs

Cancer.gov

An experimental drug has been tested in the lab and with animals and approved for testing in people by the FDA, but can’t yet be advertised, sold, or prescribed. Experimental drugs may be available through clinical trials or expanded access programs - learn more about these programs and how to talk to your doctor.

The Experimental Design Assistant.

PubMed

Percie du Sert, Nathalie; Bamsey, Ian; Bate, Simon T; Berdoy, Manuel; Clark, Robin A; Cuthill, Innes; Fry, Derek; Karp, Natasha A; Macleod, Malcolm; Moon, Lawrence; Stanford, S Clare; Lings, Brian

2017-09-01

Addressing the common problems that researchers encounter when designing and analysing animal experiments will improve the reliability of in vivo research. In this article, the Experimental Design Assistant (EDA) is introduced. The EDA is a web-based tool that guides the in vivo researcher through the experimental design and analysis process, providing automated feedback on the proposed design and generating a graphical summary that aids communication with colleagues, funders, regulatory authorities, and the wider scientific community. It will have an important role in addressing causes of irreproducibility.

Quasi experimental designs in pharmacist intervention research.

PubMed

Krass, Ines

2016-06-01

Background In the field of pharmacist intervention research it is often difficult to conform to the rigorous requirements of the "true experimental" models, especially the requirement of randomization. When randomization is not feasible, a practice based researcher can choose from a range of "quasi-experimental designs" i.e., non-randomised and at time non controlled. Objective The aim of this article was to provide an overview of quasi-experimental designs, discuss their strengths and weaknesses and to investigate their application in pharmacist intervention research over the previous decade. Results In the literature quasi experimental studies may be classified into five broad categories: quasi-experimental design without control groups; quasi-experimental design that use control groups with no pre-test; quasi-experimental design that use control groups and pre-tests; interrupted time series and stepped wedge designs. Quasi-experimental study design has consistently featured in the evolution of pharmacist intervention research. The most commonly applied of all quasi experimental designs in the practice based research literature are the one group pre-post-test design and the non-equivalent control group design i.e., (untreated control group with dependent pre-tests and post-tests) and have been used to test the impact of pharmacist interventions in general medications management as well as in specific disease states. Conclusion Quasi experimental studies have a role to play as proof of concept, in the pilot phases of interventions when testing different intervention components, especially in complex interventions. They serve to develop an understanding of possible intervention effects: while in isolation they yield weak evidence of clinical efficacy, taken collectively, they help build a body of evidence in support of the value of pharmacist interventions across different practice settings and countries. However, when a traditional RCT is not feasible for

Determination of Trace Concentration in TMD Detectors using PGAA

NASA Astrophysics Data System (ADS)

Tomandl, I.; Viererbl, L.; Kudějová, P.; Lahodová, Z.; Klupák, V.; Fikrle, M.

2015-05-01

Transmutation detectors could be alternative to the traditional activation detector method for neutron fluence dosimetry at power nuclear reactors. This new method require an isotopically highly-sensitive, non-destructive in sense of compactness as well as isotopic content, precise and standardly used analytical method for trace concentration determination. The capability of Prompt Gamma-ray Activation Analysis (PGAA) for determination of trace concentrations of transmuted stable nuclides in the metallic foils of Ni, Au, Cu and Nb, which were irradiated for 21 days in the reactor core at the LVR-15 research reactor in Řež, is reported. The PGAA measurements of these activation foils were performed at the PGAA facility at Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRMII) in Garching.

Impacts of Heterogeneous Recycle in Fast Reactors on Overall Fuel Cycle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Temitope A. Taiwo; Samuel E. Bays; Abdullatif M. Yacout

2011-03-01

A study in the United States has evaluated the attributes of the heterogeneous recycle approach for plutonium and minor actinide transmutation in fast reactor fuel cycles, with comparison to the homogeneous recycle approach, where pertinent. The work investigated the characteristics, advantages, and disadvantages of the approach in the overall fuel cycle, including reactor transmutation, systems and safety impacts, fuel separation and fabrication issues, and proliferation risk and transportation impacts. For this evaluation, data from previous and ongoing national studies on heterogeneous recycle were reviewed and synthesized. Where useful, information from international sources was included in the findings. The intent ofmore » the work was to provide a comprehensive assessment of the heterogeneous recycle approach at the current time.« less

27 CFR 24.77 - Experimental wine.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Experimental wine. (a) General. Any scientific university, college of learning, or institution of scientific research may, without payment of tax, produce, receive, blend, treat, and store wine for experimental or...

27 CFR 24.77 - Experimental wine.

Code of Federal Regulations, 2011 CFR

2011-04-01

... Experimental wine. (a) General. Any scientific university, college of learning, or institution of scientific research may, without payment of tax, produce, receive, blend, treat, and store wine for experimental or...

TANGRA-Setup for the Investigation of Nuclear Fission Induced by 14.1 MeV Neutrons

NASA Astrophysics Data System (ADS)

Ruskov, I. N.; Kopatch, Yu. N.; Bystritsky, V. M.; Skoy, V. R.; Shvetsov, V. N.; Hambsch, F.-J.; Oberstedt, S.; Noy, R. Capote; Sedyshev, P. V.; Grozdanov, D. N.; Ivanov, I. Zh.; Aleksakhin, V. Yu.; Bogolubov, E. P.; Barmakov, Yu. N.; Khabarov, S. V.; Krasnoperov, A. V.; Krylov, A. R.; Obhođaš, J.; Pikelner, L. B.; Rapatskiy, V. L.; Rogachev, A. V.; Rogov, Yu. N.; Ryzhkov, V. I.; Sadovsky, A. B.; Salmin, R. A.; Sapozhnikov, M. G.; Slepnev, V. M.; Sudac, D.; Tarasov, O. G.; Valković, V.; Yurkov, D. I.; Zamyatin, N. I.; Zeynalov, Sh. S.; Zontikov, A. O.; Zubarev, E. V.

The new experimental setup TANGRA (Tagged Neutrons & Gamma Rays), for the investigation of neutron induced nuclear reactions, e.g. (n,xn'), (n,xn'γ), (n,γ), (n,f), on a number of important isotopes for nuclear science and engineering (235,238U, 237Np, 239Pu, 244,245,248Cm) is under construction and being tested at the Frank Laboratory of Neutron Physics (FLNP) of the Joint Institute for Nuclear Research (JINR) in Dubna. The TANGRA setup consists of: a portable neutron generator ING-27, with a 64-pixel Si charge-particle detector incorporated into its vacuum chamber for registering of α-particles formed in the T(d, n)4He reaction, as a source of 14.1 MeV steady-state neutrons radiation with an intensity of ∼5x107n/s; a combined iron (Fe), borated polyethylene (BPE) and lead (Pb) compact shielding-collimator; a reconfigurable multi-detector (neutron plus gamma ray detecting system); a fast computer with 2 (x16 channels) PCI-E 100 MHz ADC cards for data acquisition and hard disk storage; Linux ROOT data acquisition, visualization and analysis software. The signals from the α-particle detector are used to 'tag' the neutrons with the coincident α-particles. Counting the coincidences between the α-particle and the reaction-product detectors in a 20ns time-interval improves the effect/background-ratio by a factor of ∼200 as well as the accuracy in the neutron flux determination, which decreases noticeably the overall experimental data uncertainty.

16 CFR 1702.9 - Relevant experimental data.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Relevant experimental data. 1702.9 Section... AND REQUIREMENTS § 1702.9 Relevant experimental data. Experimental data are generated in both animals.... Certain toxicological effects cannot generally be evaluated in human beings. This is especially true of...

16 CFR 1702.9 - Relevant experimental data.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Relevant experimental data. 1702.9 Section... AND REQUIREMENTS § 1702.9 Relevant experimental data. Experimental data are generated in both animals.... Certain toxicological effects cannot generally be evaluated in human beings. This is especially true of...

16 CFR 1702.9 - Relevant experimental data.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Relevant experimental data. 1702.9 Section... AND REQUIREMENTS § 1702.9 Relevant experimental data. Experimental data are generated in both animals.... Certain toxicological effects cannot generally be evaluated in human beings. This is especially true of...

16 CFR 1702.9 - Relevant experimental data.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Relevant experimental data. 1702.9 Section... AND REQUIREMENTS § 1702.9 Relevant experimental data. Experimental data are generated in both animals.... Certain toxicological effects cannot generally be evaluated in human beings. This is especially true of...

The Experimental Design Assistant

PubMed Central

Bamsey, Ian; Bate, Simon T.; Berdoy, Manuel; Clark, Robin A.; Cuthill, Innes; Fry, Derek; Karp, Natasha A.; Macleod, Malcolm; Moon, Lawrence; Stanford, S. Clare; Lings, Brian

2017-01-01

Addressing the common problems that researchers encounter when designing and analysing animal experiments will improve the reliability of in vivo research. In this article, the Experimental Design Assistant (EDA) is introduced. The EDA is a web-based tool that guides the in vivo researcher through the experimental design and analysis process, providing automated feedback on the proposed design and generating a graphical summary that aids communication with colleagues, funders, regulatory authorities, and the wider scientific community. It will have an important role in addressing causes of irreproducibility. PMID:28957312

Physical versus Virtual Manipulative Experimentation in Physics Learning

ERIC Educational Resources Information Center

Zacharia, Zacharias C.; Olympiou, Georgios

2011-01-01

The aim of this study was to investigate whether physical or virtual manipulative experimentation can differentiate physics learning. There were four experimental conditions, namely Physical Manipulative Experimentation (PME), Virtual Manipulative Experimentation (VME), and two sequential combinations of PME and VME, as well as a control condition…

Using semantics for representing experimental protocols.

PubMed

Giraldo, Olga; García, Alexander; López, Federico; Corcho, Oscar

2017-11-13

An experimental protocol is a sequence of tasks and operations executed to perform experimental research in biological and biomedical areas, e.g. biology, genetics, immunology, neurosciences, virology. Protocols often include references to equipment, reagents, descriptions of critical steps, troubleshooting and tips, as well as any other information that researchers deem important for facilitating the reusability of the protocol. Although experimental protocols are central to reproducibility, the descriptions are often cursory. There is the need for a unified framework with respect to the syntactic structure and the semantics for representing experimental protocols. In this paper we present "SMART Protocols ontology", an ontology for representing experimental protocols. Our ontology represents the protocol as a workflow with domain specific knowledge embedded within a document. We also present the S ample I nstrument R eagent O bjective (SIRO) model, which represents the minimal common information shared across experimental protocols. SIRO was conceived in the same realm as the Patient Intervention Comparison Outcome (PICO) model that supports search, retrieval and classification purposes in evidence based medicine. We evaluate our approach against a set of competency questions modeled as SPARQL queries and processed against a set of published and unpublished protocols modeled with the SP Ontology and the SIRO model. Our approach makes it possible to answer queries such as Which protocols use tumor tissue as a sample. Improving reporting structures for experimental protocols requires collective efforts from authors, peer reviewers, editors and funding bodies. The SP Ontology is a contribution towards this goal. We build upon previous experiences and bringing together the view of researchers managing protocols in their laboratory work. Website: https://smartprotocols.github.io/ .

High-Throughput Experimental Approach Capabilities | Materials Science |

Science.gov Websites

NREL High-Throughput Experimental Approach Capabilities High-Throughput Experimental Approach by yellow and is for materials in the upper right sector. NREL's high-throughput experimental ,Te) and oxysulfide sputtering Combi-5: Nitrides and oxynitride sputtering We also have several non

Considering RNAi experimental design in parasitic helminths.

PubMed

Dalzell, Johnathan J; Warnock, Neil D; McVeigh, Paul; Marks, Nikki J; Mousley, Angela; Atkinson, Louise; Maule, Aaron G

2012-04-01

Almost a decade has passed since the first report of RNA interference (RNAi) in a parasitic helminth. Whilst much progress has been made with RNAi informing gene function studies in disparate nematode and flatworm parasites, substantial and seemingly prohibitive difficulties have been encountered in some species, hindering progress. An appraisal of current practices, trends and ideals of RNAi experimental design in parasitic helminths is both timely and necessary for a number of reasons: firstly, the increasing availability of parasitic helminth genome/transcriptome resources means there is a growing need for gene function tools such as RNAi; secondly, fundamental differences and unique challenges exist for parasite species which do not apply to model organisms; thirdly, the inherent variation in experimental design, and reported difficulties with reproducibility undermine confidence. Ideally, RNAi studies of gene function should adopt standardised experimental design to aid reproducibility, interpretation and comparative analyses. Although the huge variations in parasite biology and experimental endpoints make RNAi experimental design standardization difficult or impractical, we must strive to validate RNAi experimentation in helminth parasites. To aid this process we identify multiple approaches to RNAi experimental validation and highlight those which we deem to be critical for gene function studies in helminth parasites.

Transmutation Fuel Fabrication-Fiscal Year 2016

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fielding, Randall Sidney; Grover, Blair Kenneth

ABSTRACT Nearly all of the metallic fuel that has been irradiated and characterized by the Advanced Fuel Campaign, and its earlier predecessors, has been arc cast. Arc casting is a very flexible method of casting lab scale quantities of materials. Although the method offers flexibility, it is an operator dependent process. Small changes in parameter space or alloy composition may affect how the material is cast. This report provides a historical insight in how the casting process has been modified over the history of the advanced fuels campaign as well as the physical parameters of the fuels cast in fiscalmore » year 2016.« less

Reform of experimental teaching based on quality cultivation

NASA Astrophysics Data System (ADS)

Wang, Wei; Yan, Xingwei; Liu, Wei; Yao, Tianfu; Shi, Jianhua; Lei, Bing; Hu, Haojun

2017-08-01

Experimental teaching plays an import part in quality education which devotes to cultivating students with innovative spirit, strong technological talents and practical ability. However, in the traditional experimental teaching mode, the experiments are treated as a vassal or supplementary mean of theoretical teaching, and students prefer focus on theory to practice. Therefore, the traditional experimental teaching mode is difficult to meet the requirements of quality education. To address this issue, the reform of experimental teaching is introduced in this paper taking the photoelectric detector experiment as the example. The new experimental teaching mode is designed from such aspects as experimental content, teaching method and experimental evaluation. With the purpose of cultivating students' practical ability, two different-level experimental content is designed. Not only the basic experiments used to verify the theory are set to consolidate the students' learned theoretical knowledge, but also comprehensive experiments are designed to encourage the students to apply their learned knowledge to solve practical problems. In the teaching process, heuristic teaching thought is adopt and the traditional `teacher-centered' teaching form is replaced by `student-centered' form, which aims to encourage students to design the experimental systems by their own with the teacher's guidance. In addition to depending on stimulating the students' interest of science research, experimental evaluation is necessary to urge students to complete the experiments efficiently. Multifaceted evaluation method is proposed to test the students' mastery of theoretical knowledge, practice ability, troubleshooting and problem solving skills, and innovation capability comprehensively. Practices demonstrated the satisfying effect of our experimental teaching mode.

Students' Epistemologies about Experimental Physics: Validating the Colorado Learning Attitudes about Science Survey for Experimental Physics

ERIC Educational Resources Information Center

Wilcox, Bethany R.; Lewandowski, H. J.

2016-01-01

Student learning in instructional physics labs represents a growing area of research that includes investigations of students' beliefs and expectations about the nature of experimental physics. To directly probe students' epistemologies about experimental physics and support broader lab transformation efforts at the University of Colorado Boulder…

Experimental flexible pavements.

DOT National Transportation Integrated Search

1971-01-01

A program of construction and the performance evaluation of three major Virginia experimental flexible pavements is reported. The objective of the program was to evaluate the performance of pavements incorporating new or timely design concepts and to...

[The ethics of animal experimentation].

PubMed

Goffi, Jean-Yves

2013-01-01

The paper starts with a short definition of animal experimentation, then three main approaches to the practice are considered: unconditional approval (as advocated by Claude Bernard), conditional and restricted approval (as advocated by Peter Singer) and strict prohibition (as advocated by Tom Regan and Gary Francione). It is argued that what is actually approved or condemned in animal experimentation is the value of the scientific enterprise.

ORNL actinide materials and a new detection system for superheavy nuclei

NASA Astrophysics Data System (ADS)

Rykaczewski, Krzysztof P.; Roberto, James B.; Brewer, Nathan T.; Utyonkov, Vladimir K.

2016-12-01

The actinide resources and production capabilities at Oak Ridge National Laboratory (ORNL) are reviewed, including potential electromagnetic separation of rare radioactive materials. The first experiments at the Dubna Gas Filled Recoil Separator (DGFRS) with a new digital detection system developed at ORNL and University of Tennessee Knoxville (UTK) are presented. These studies used 240Pu material provided by ORNL and mixed-Cf targets made at ORNL. The proposal to use an enriched 251Cf target and a large dose of 58Fe beam to reach the N = 184 shell closure and to observe new elements with Z = 124, 122 and 120 is discussed.

Mass analyzer ``MASHA'' high temperature target and plasma ion source

NASA Astrophysics Data System (ADS)

Semchenkov, A. G.; Rassadov, D. N.; Bekhterev, V. V.; Bystrov, V. A.; Chizov, A. Yu.; Dmitriev, S. N.; Efremov, A. A.; Guljaev, A. V.; Kozulin, E. M.; Oganessian, Yu. Ts.; Starodub, G. Ya.; Voskresensky, V. M.; Bogomolov, S. L.; Paschenko, S. V.; Zelenak, A.; Tikhonov, V. I.

2004-05-01

A new separator and mass analyzer of super heavy atoms (MASHA) has been created at the FLNR JINR Dubna to separate and measure masses of nuclei and molecules with precision better than 10-3. First experiments with the FEBIAD plasma ion source have been done and give an efficiency of ionization of up to 20% for Kr with a low flow test leak (6 particle μA). We suppose a magnetic field optimization, using the additional electrode (einzel lens type) in the extracting system, and an improving of the vacuum conditions in order to increase the ion source efficiency.

Precooling of a dilution refrigerator

NASA Astrophysics Data System (ADS)

Pavlov, Valentin N.

A non-trivial system for Precooling of the dilution refrigerator for low-temperatureexperiments on an ISOL-facility is described in detail. Neither exchange gas in the vacuum jacket of the cryostat nor a demantable window in the 4K shield are used in this system. Instead of that the dilution refrigerator is supplemented with two capillaries and a heater in order to cool all low-temperature parts of the refrigerator down to start conditions. The, time of cooling depends on the total impedance of the first heat exchanger. Such system has been developed and tested in Dubna, and it is in operation.

Liquid metal ion source assembly for external ion injection into an electron string ion source (ESIS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Segal, M. J., E-mail: mattiti@gmail.com; University of Cape Town, Rondebosch, Cape Town 7700; Bark, R. A.

An assembly for a commercial Ga{sup +} liquid metal ion source in combination with an ion transportation and focusing system, a pulse high-voltage quadrupole deflector, and a beam diagnostics system has been constructed in the framework of the iThemba LABS (Cape Town, South Africa)—JINR (Dubna, Russia) collaboration. First, results on Ga{sup +} ion beam commissioning will be presented. Outlook of further experiments for measurements of charge breeding efficiency in the electron string ion source with the use of external injection of Ga{sup +} and Au{sup +} ion beams will be reported as well.

Rotational Invariance of the 2d Spin - Spin Correlation Function

NASA Astrophysics Data System (ADS)

Pinson, Haru

2012-09-01

At the critical temperature in the 2d Ising model on the square lattice, we establish the rotational invariance of the spin-spin correlation function using the asymptotics of the spin-spin correlation function along special directions (McCoy and Wu in the two dimensional Ising model. Harvard University Press, Cambridge, 1973) and the finite difference Hirota equation for which the spin-spin correlation function is shown to satisfy (Perk in Phys Lett A 79:3-5, 1980; Perk in Proceedings of III international symposium on selected topics in statistical mechanics, Dubna, August 22-26, 1984, JINR, vol II, pp 138-151, 1985).

Heavy neutron rich nuclei: production and investigation

NASA Astrophysics Data System (ADS)

Zemlyanoy, S.; Avvakumov, K.; Kazarinov, N.; Fedosseev, V.; Bark, R.; Blazczak, Z.; Janas, Z.

2018-05-01

For production and investigation of heavy neutron rich nuclei devoted the new setup, which is under construction at Flerov Laboratory for Nuclear Reactions (FLNR) - JINR, Dubna now. This setup is planned to exploit available beams from the U-400M cyclotron in low energy multi-nucleon transfer reactions to study exotic neutron-rich nuclei located in the “north-east” region of nuclear map. Products from 4.5 to 9 MeV/nucleon heavy-ion collisions, such as 136Xe on 208Pb, are to be captured in a gas cell and selectively laser-ionized in a sextupole (quadrupole) ion guide extraction system.

Quantitative Evaluation of Management Courses: Part 1

ERIC Educational Resources Information Center

Cunningham, Cyril

1973-01-01

The author describes how he developed a method of evaluating and comparing management courses of different types and lengths by applying an ordinal system of relative values using a process of transmutation. (MS)

A new dimension in space experimentation

NASA Technical Reports Server (NTRS)

1983-01-01

Space experimentation, cosmic origins, the long-term effects of the space environment on living things, the long-term effects of space environment on materials and hardware, seeds in space, power generation in space, experimentation with crystals, and thermal control are discussed.

Optimizing Experimental Designs: Finding Hidden Treasure.

USDA-ARS?s Scientific Manuscript database

Classical experimental design theory, the predominant treatment in most textbooks, promotes the use of blocking designs for control of spatial variability in field studies and other situations in which there is significant variation among heterogeneity among experimental units. Many blocking design...

Constitutive Model Calibration via Autonomous Multiaxial Experimentation (Postprint)

DTIC Science & Technology

2016-09-17

test machine. Experimental data is reduced and finite element simulations are conducted in parallel with the test based on experimental strain...data is reduced and finite element simulations are conducted in parallel with the test based on experimental strain conditions. Optimization methods...be used directly in finite element simulations of more complex geometries. Keywords Axial/torsional experimentation • Plasticity • Constitutive model

Quasi-Experimental Designs for Causal Inference

ERIC Educational Resources Information Center

Kim, Yongnam; Steiner, Peter

2016-01-01

When randomized experiments are infeasible, quasi-experimental designs can be exploited to evaluate causal treatment effects. The strongest quasi-experimental designs for causal inference are regression discontinuity designs, instrumental variable designs, matching and propensity score designs, and comparative interrupted time series designs. This…

Cancer in Light of Experimental Evolution

PubMed Central

Sprouffske, Kathleen; Merlo, Lauren M.F.; Gerrish, Philip J.; Maley, Carlo C.; Sniegowski, Paul D.

2012-01-01

Cancer initiation, progression, and the emergence of therapeutic resistance are evolutionary phenomena of clonal somatic cell populations. Studies in microbial experimental evolution and the theoretical work inspired by such studies are yielding deep insights into the evolutionary dynamics of clonal populations, yet there has been little explicit consideration of the relevance of this rapidly growing field to cancer biology. Here, we examine how the understanding of mutation, selection, and spatial structure in clonal populations that is emerging from experimental evolution may be applicable to cancer. Along the way, we discuss some significant ways in which cancer differs from the model systems used in experimental evolution. Despite these differences, we argue that enhanced prediction and control of cancer may be possible using ideas developed in the context of experimental evolution, and we point out some prospects for future research at the interface between these traditionally separate areas. PMID:22975007

Measurement of 235U(n,n'γ) and 235U(n,2nγ) reaction cross sections

NASA Astrophysics Data System (ADS)

Kerveno, M.; Thiry, J. C.; Bacquias, A.; Borcea, C.; Dessagne, P.; Drohé, J. C.; Goriely, S.; Hilaire, S.; Jericha, E.; Karam, H.; Negret, A.; Pavlik, A.; Plompen, A. J. M.; Romain, P.; Rouki, C.; Rudolf, G.; Stanoiu, M.

2013-02-01

The design of generation IV nuclear reactors and the studies of new fuel cycles require knowledge of the cross sections of various nuclear reactions. Our research is focused on (n,xnγ) reactions occurring in these new reactors. The aim is to measure unknown cross sections and to reduce the uncertainty on present data for reactions and isotopes of interest for transmutation or advanced reactors. The present work studies the 235U(n,n'γ) and 235U(n,2nγ) reactions in the fast neutron energy domain (up to 20 MeV). The experiments were performed with the Geel electron linear accelerator GELINA, which delivers a pulsed white neutron beam. The time characteristics enable measuring neutron energies with the time-of-flight (TOF) technique. The neutron induced reactions [in this case inelastic scattering and (n,2n) reactions] are identified by on-line prompt γ spectroscopy with an experimental setup including four high-purity germanium (HPGe) detectors. A fission ionization chamber is used to monitor the incident neutron flux. The experimental setup and analysis methods are presented and the model calculations performed with the TALYS-1.2 code are discussed.

Theories of Variable Mass Particles and Low Energy Nuclear Phenomena

NASA Astrophysics Data System (ADS)

Davidson, Mark

2014-02-01

Variable particle masses have sometimes been invoked to explain observed anomalies in low energy nuclear reactions (LENR). Such behavior has never been observed directly, and is not considered possible in theoretical nuclear physics. Nevertheless, there are covariant off-mass-shell theories of relativistic particle dynamics, based on works by Fock, Stueckelberg, Feynman, Greenberger, Horwitz, and others. We review some of these and we also consider virtual particles that arise in conventional Feynman diagrams in relativistic field theories. Effective Lagrangian models incorporating variable mass particle theories might be useful in describing anomalous nuclear reactions by combining mass shifts together with resonant tunneling and other effects. A detailed model for resonant fusion in a deuterium molecule with off-shell deuterons and electrons is presented as an example. Experimental means of observing such off-shell behavior directly, if it exists, is proposed and described. Brief explanations for elemental transmutation and formation of micro-craters are also given, and an alternative mechanism for the mass shift in the Widom-Larsen theory is presented. If variable mass theories were to find experimental support from LENR, then they would undoubtedly have important implications for the foundations of quantum mechanics, and practical applications may arise.

Experimental plasma research project summaries

NASA Astrophysics Data System (ADS)

1992-06-01

This is the latest in a series of Project Summary books that date back to 1976. It is the first after a hiatus of several years. They are published to provide a short description of each project supported by the Experimental Plasma Research Branch of the Division of Applied Plasma Physics in the Office of Fusion Energy. The Experimental Plasma Research Branch seeks to provide a broad range of experimental data, physics understanding, and new experimental techniques that contribute to operation, interpretation, and improvement of high temperature plasma as a source of fusion energy. In pursuit of these objectives, the branch supports research at universities, DOE laboratories, other federal laboratories, and industry. About 70 percent of the funds expended are spent at universities and a significant function of this program is the training of students in fusion physics. The branch supports small- and medium-scale experimental studies directly related to specific critical plasma issues of the magnetic fusion program. Plasma physics experiments are conducted on transport of particles and energy within plasma. Additionally, innovative approaches for operating, controlling, and heating plasma are evaluated for application to the larger confinement devices of the magnetic fusion program. New diagnostic approaches to measuring the properties of high temperature plasmas are developed to the point where they can be applied with confidence on the large-scale confinement experiments. Atomic data necessary for impurity control, interpretation of diagnostic data, development of heating devices, and analysis of cooling by impurity ion radiation are obtained. The project summaries are grouped into the three categories of plasma physics, diagnostic development, and atomic physics.

Quantum Experimental Data in Psychology and Economics

NASA Astrophysics Data System (ADS)

Aerts, Diederik; D'Hooghe, Bart; Haven, Emmanuel

2010-12-01

We prove a theorem which shows that a collection of experimental data of probabilistic weights related to decisions with respect to situations and their disjunction cannot be modeled within a classical probabilistic weight structure in case the experimental data contain the effect referred to as the ‘disjunction effect’ in psychology. We identify different experimental situations in psychology, more specifically in concept theory and in decision theory, and in economics (namely situations where Savage’s Sure-Thing Principle is violated) where the disjunction effect appears and we point out the common nature of the effect. We analyze how our theorem constitutes a no-go theorem for classical probabilistic weight structures for common experimental data when the disjunction effect is affecting the values of these data. We put forward a simple geometric criterion that reveals the non classicality of the considered probabilistic weights and we illustrate our geometrical criterion by means of experimentally measured membership weights of items with respect to pairs of concepts and their disjunctions. The violation of the classical probabilistic weight structure is very analogous to the violation of the well-known Bell inequalities studied in quantum mechanics. The no-go theorem we prove in the present article with respect to the collection of experimental data we consider has a status analogous to the well known no-go theorems for hidden variable theories in quantum mechanics with respect to experimental data obtained in quantum laboratories. Our analysis puts forward a strong argument in favor of the validity of using the quantum formalism for modeling the considered psychological experimental data as considered in this paper.

Experimental and numerical study of the British Experimental Rotor Programme blade

NASA Technical Reports Server (NTRS)

Brocklehurst, Alan; Duque, Earl P. N.

1990-01-01

Wind-tunnel tests on the British Experimental Rotor Programme (BERP) tip are described, and the results are compared with computational fluid dynamics (CFD) results. The test model was molded using the Lynx-BERP blade tooling to provide a semispan, cantilever wing comprising the outboard 30 percent of the rotor blade. The tests included both surface-pressure measurements and flow visualization to obtain detailed information of the flow over the BERP tip for a range of angles of attack. It was observed that, outboard of the notch, favorable pressure gradients exist which ensure attached flow, and that the tip vortex also remains stable to large angles of attack. On the rotor, these features yield a very gradual break in control loads when the retreating-blade limit is eventually reached. Computational and experimental results were generally found to be in good agreement.

[Ethical issue in animal experimentation].

PubMed

Parodi, André-Laurent

2009-11-01

In the 1970s, under pressure from certain sections of society and thanks to initiatives by several scientific research teams, committees charged with improving the conditions of laboratory animals started to be created, first in the United States and subsequently in Europe. This led to the development of an ethical approach to animal experimentation, taking into account new scientific advances. In addition to the legislation designed to provide a legal framework for animal experimentation and to avoid abuses, this ethical approach, based on the concept that animals are sentient beings, encourages greater respect of laboratory animals and the implementation of measures designed to reduce their suffering. Now, all animal experiments must first receive ethical approval--from in-house committees in the private sector and from regional committees for public institutions. Very recently, under the impetus of the French ministries of research and agriculture, the National committee for ethical animal experimentation published a national ethical charter on animal experimentation, setting the basis for responsible use of animals for scientific research and providing guidelines for the composition and functioning of ethics committees. Inspired by the scientific community itself this ethical standardization should help to assuage--but not eliminate--the reticence and hostility expressed by several sections of society.

Anesthesia in Experimental Stroke Research

PubMed Central

Hoffmann, Ulrike; Sheng, Huaxin; Ayata, Cenk; Warner, David S.

2016-01-01

Anesthetics have enabled major advances in development of experimental models of human stroke. Yet their profound pharmacologic effects on neural function can confound the interpretation of experimental stroke research. Anesthetics have drug and dose-specific effects on cerebral blood flow and metabolism, neurovascular coupling, autoregulation, ischemic depolarizations, excitotoxicity, inflammation, neural networks, and numerous molecular pathways relevant for stroke outcome. Both pre- and post-conditioning properties have been described. Anesthetics also modulate systemic arterial blood pressure, lung ventilation, and thermoregulation, all of which may interact with the ischemic insult as well as the therapeutic interventions. These confounds present a dilemma. Here, we provide an overview of the anesthetic mechanisms of action and molecular and physiologic effects on factors relevant to stroke outcomes that can guide the choice and optimization of the anesthetic regimen in experimental stroke. PMID:27534542

First steps in experimental cancer evolution

PubMed Central

Taylor, Tiffany B; Johnson, Louise J; Jackson, Robert W; Brockhurst, Michael A; Dash, Philip R

2013-01-01

Evolutionary processes play a central role in the development, progression and response to treatment of cancers. The current challenge facing researchers is to harness evolutionary theory to further our understanding of the clinical progression of cancers. Central to this endeavour will be the development of experimental systems and approaches by which theories of cancer evolution can be effectively tested. We argue here that the experimental evolution approach – whereby evolution is observed in real time and which has typically employed microorganisms – can be usefully applied to cancer. This approach allows us to disentangle the ecological causes of natural selection, identify the genetic basis of evolutionary changes and determine their repeatability. Cell cultures used in cancer research share many of the desirable traits that make microorganisms ideal for studying evolution. As such, experimental cancer evolution is feasible and likely to give great insight into the selective pressures driving the evolution of clinically destructive cancer traits. We highlight three areas of evolutionary theory with importance to cancer biology that are amenable to experimental evolution: drug resistance, social evolution and resource competition. Understanding the diversity, persistence and evolution of cancers is vital for treatment and drug development, and an experimental evolution approach could provide strategic directions and focus for future research. PMID:23745144

Experimental Study of Impinging Jets Flow-Fields

DTIC Science & Technology

2016-07-27

1 Grant # N000141410830 Experimental Study of Impinging Jet Flow-Fields Final Report for Period: Jun 15, 2014 – Jun 14, 2016 PI: Dennis K...impinging jet model in the absence of any jet heating. The results of the computations had been compared with the experimental data produced in the...of the validity of the computations, and also of the experimental approach. Figure 12a. Initial single

[Experimental studies of micromotor headpieces].

PubMed

Kanaev, V F; Repin, V A

1982-01-01

Experimental studies of handpieces for micromotors have been performed to make more precise their operating parameters. The special stand has been used for the measurements of the following data: head temperature, power losses in handpieces at no-load, and operating power required for machining by means of spherical burrs. The experimental results made it possible to specify more exactly the range of handpiece rotational speeds and to select optimum loads under reliability testing.

47 CFR 73.1510 - Experimental authorizations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Experimental authorizations. 73.1510 Section 73... conducted at any time the station is authorized to operate, but the minimum required schedule of programming... regularly scheduled programming concurrently with the experimental transmission if there is no significant...

47 CFR 73.1510 - Experimental authorizations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 4 2011-10-01 2011-10-01 false Experimental authorizations. 73.1510 Section 73... conducted at any time the station is authorized to operate, but the minimum required schedule of programming... regularly scheduled programming concurrently with the experimental transmission if there is no significant...

The Experimental Design Ability Test (EDAT)

ERIC Educational Resources Information Center

Sirum, Karen; Humburg, Jennifer

2011-01-01

Higher education goals include helping students develop evidence based reasoning skills; therefore, scientific thinking skills such as those required to understand the design of a basic experiment are important. The Experimental Design Ability Test (EDAT) measures students' understanding of the criteria for good experimental design through their…

Cancer in light of experimental evolution.

PubMed

Sprouffske, Kathleen; Merlo, Lauren M F; Gerrish, Philip J; Maley, Carlo C; Sniegowski, Paul D

2012-09-11

Cancer initiation, progression, and the emergence of therapeutic resistance are evolutionary phenomena of clonal somatic cell populations. Studies in microbial experimental evolution and the theoretical work inspired by such studies are yielding deep insights into the evolutionary dynamics of clonal populations, yet there has been little explicit consideration of the relevance of this rapidly growing field to cancer biology. Here, we examine how the understanding of mutation, selection, and spatial structure in clonal populations that is emerging from experimental evolution may be applicable to cancer. Along the way, we discuss some significant ways in which cancer differs from the model systems used in experimental evolution. Despite these differences, we argue that enhanced prediction and control of cancer may be possible using ideas developed in the context of experimental evolution, and we point out some prospects for future research at the interface between these traditionally separate areas. Copyright © 2012 Elsevier Ltd. All rights reserved.

Experimental design methods for bioengineering applications.

PubMed

Keskin Gündoğdu, Tuğba; Deniz, İrem; Çalışkan, Gülizar; Şahin, Erdem Sefa; Azbar, Nuri

2016-01-01

Experimental design is a form of process analysis in which certain factors are selected to obtain the desired responses of interest. It may also be used for the determination of the effects of various independent factors on a dependent factor. The bioengineering discipline includes many different areas of scientific interest, and each study area is affected and governed by many different factors. Briefly analyzing the important factors and selecting an experimental design for optimization are very effective tools for the design of any bioprocess under question. This review summarizes experimental design methods that can be used to investigate various factors relating to bioengineering processes. The experimental methods generally used in bioengineering are as follows: full factorial design, fractional factorial design, Plackett-Burman design, Taguchi design, Box-Behnken design and central composite design. These design methods are briefly introduced, and then the application of these design methods to study different bioengineering processes is analyzed.

Athermal Annealing of Silicon

NASA Astrophysics Data System (ADS)

Fischer, R. P.; Grun, J.; Ting, A.; Felix, C.; Peckerar, M.; Fatemi, M.; Manka, C. K.

1999-11-01

Current semiconductor annealing methods are based on thermal processes which are accompanied by diffusion that degrades the definition of device features or causes other problems. This will be a serious obstacle for the production of next-generation ultra-high density, low power semiconductor devices. Experiments underway at NRL utilize a new annealing method which is much faster than thermal annealing and does not depend upon thermal energy (J. Grun, et al)., Phys. Rev. Letters 78, 1584 (1997).. A 10 J, 30 nsec, 1.053 nm wavelength laser pulse is focussed to approximately 1 mm diameter on a silicon sample. Acoustic and shock waves propagate from the impact region, which deposit mechanical energy into the material and anneal the silicon. Experimental results will be presented on annealing neutron-transmutation-doped (NTD) and ion implanted silicon samples with impurity concentrations from 1 × 10^15-3 × 10^20/cm^3.

On the onset of void swelling in pure tungsten under neutron irradiation: An object kinetic Monte Carlo approach

NASA Astrophysics Data System (ADS)

Castin, N.; Bakaev, A.; Bonny, G.; Sand, A. E.; Malerba, L.; Terentyev, D.

2017-09-01

We propose an object kinetic Monte Carlo (OKMC) model for describing the microstructural evolution in pure tungsten under neutron irradiation. We here focus on low doses (under 1 dpa), and we neglect transmutation in first approximation. The emphasis is mainly centred on an adequate description of neutron irradiation, the subsequent introduction of primary defects, and their thermal diffusion properties. Besides grain boundaries and the dislocation network, our model includes the contribution of carbon impurities, which are shown to have a strong influence on the onset of void swelling. Our parametric study analyses the quality of our model in detail, and confronts its predictions with experimental microstructural observations with satisfactory agreement. We highlight the importance for an accurate determination of the dissolved carbon content in the tungsten matrix, and we advocate for an accurate description of atomic collision cascades, in light of the sensitivity of our results with respect to correlated recombination.

EXPERIMENTAL ANIMAL MAINTENANCE

DOEpatents

Finkel, M.P.

1962-01-22

A method of housing experimental animals such as mice in individual tube- like plastic enclosures is described. Contrary to experience, when this was tried with metal the mice did not become panicky. Group housing, with its attendant difficulties, may thus be dispensed with. (AEC)

Cross-sections of residual nuclei from deuteron irradiation of thin thorium target at energy 7 GeV

NASA Astrophysics Data System (ADS)

Vespalec, Radek; Adam, Jindrich; Baldin, Anton Alexandrovich; Khushvaktov, Jurabek; Solnyshkin, Alexander Alexandrovich; Tsoupko-Sitnikov, Vsevolod Mikhailovich; Tyutyunikov, Sergey Ivanovich; Vrzalova, Jitka; Zavorka, Lukas; Zeman, Miroslav

2017-09-01

The residual nuclei yields are of great importance for the estimation of basic radiation-technology characteristics (like a total target activity, production of long-lived nuclides etc.) of accelerator driven systems planned for transmutation of spent nuclear fuel and for a design of radioisotopes production facilities. Experimental data are also essential for validation of nuclear codes describing various stages of a spallation reaction. Therefore, the main aim of this work is to add new experimental data in energy region of relativistic deuterons, as similar data are missing in nuclear databases. The sample made of thin natural thorium foil was irradiated at JINR Nuclotron accelerator with a deuteron beam of the total kinetic energy 7 GeV. Integral number of deuterons was determined with the use of aluminum activation detectors. Products of deuteron induced spallation reaction were qualified and quantified by means of gamma-ray spectroscopy method. Several important spectroscopic corrections were applied to obtain results of high accuracy. Experimental cumulative and independent cross-sections were determined for more than 80 isotopes including meta-stable isomers. The total uncertainty of results rarely exceeded 9%. Experimental results were compared with MCNP6.1 Monte-Carlo code predictions. Generally, experimental and calculated cross-sections are in a reasonably good agreement, with the exception of a few light isotopes in a fragmentation region, where the calculations are highly under-estimated. Measured data will be useful for future development of high-energy nuclear codes. After completion, final data will be added into the EXFOR database.

Gaseous Sulfate Solubility in Glass: Experimental Method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bliss, Mary

2013-11-30

Sulfate solubility in glass is a key parameter in many commercial glasses and nuclear waste glasses. This report summarizes key publications specific to sulfate solubility experimental methods and the underlying physical chemistry calculations. The published methods and experimental data are used to verify the calculations in this report and are expanded to a range of current technical interest. The calculations and experimental methods described in this report will guide several experiments on sulfate solubility and saturation for the Hanford Waste Treatment Plant Enhanced Waste Glass Models effort. There are several tables of sulfate gas equilibrium values at high temperature tomore » guide experimental gas mixing and to achieve desired SO3 levels. This report also describes the necessary equipment and best practices to perform sulfate saturation experiments for molten glasses. Results and findings will be published when experimental work is finished and this report is validated from the data obtained.« less

Curriculum system for experimental teaching in optoelectronic information

NASA Astrophysics Data System (ADS)

Di, Hongwei; Chen, Zhenqiang; Zhang, Jun; Luo, Yunhan

2017-08-01

The experimental curriculum system is directly related to talent training quality. Based on the careful investigation of the developing request of the optoelectronic information talents in the new century, the experimental teaching goal and the content, the teaching goal was set to cultivate students' innovative consciousness, innovative thinking, creativity and problem solving ability. Through straightening out the correlation among the experimental teaching in the main courses, the whole structure design was phased out, as well as the hierarchical curriculum connotation. According to the ideas of "basic, comprehensive, applied and innovative", the construction of experimental teaching system called "triple-three" was put forward for the optoelectronic information experimental teaching practice.

Early-Life Nutritional Programming of Type 2 Diabetes: Experimental and Quasi-Experimental Evidence.

PubMed

Vaiserman, Alexander M

2017-03-05

Consistent evidence from both experimental and human studies suggest that inadequate nutrition in early life can contribute to risk of developing metabolic disorders including type 2 diabetes (T2D) in adult life. In human populations, most findings supporting a causative relationship between early-life malnutrition and subsequent risk of T2D were obtained from quasi-experimental studies ('natural experiments'). Prenatal and/or early postnatal exposures to famine were demonstrated to be associated with higher risk of T2D in many cohorts around the world. Recent studies have highlighted the importance of epigenetic regulation of gene expression as a possible major contributor to the link between the early-life famine exposure and T2D in adulthood. Findings from these studies suggest that prenatal exposure to the famine may result in induction of persistent epigenetic changes that have adaptive significance in postnatal development but can predispose to metabolic disorders including T2D at the late stages of life. In this review, quasi-experimental data on the developmental programming of T2D are summarized and recent research findings on changes in DNA methylation that mediate these effects are discussed.

Early-Life Nutritional Programming of Type 2 Diabetes: Experimental and Quasi-Experimental Evidence

PubMed Central

Vaiserman, Alexander M.

2017-01-01

Consistent evidence from both experimental and human studies suggest that inadequate nutrition in early life can contribute to risk of developing metabolic disorders including type 2 diabetes (T2D) in adult life. In human populations, most findings supporting a causative relationship between early-life malnutrition and subsequent risk of T2D were obtained from quasi-experimental studies (‘natural experiments’). Prenatal and/or early postnatal exposures to famine were demonstrated to be associated with higher risk of T2D in many cohorts around the world. Recent studies have highlighted the importance of epigenetic regulation of gene expression as a possible major contributor to the link between the early-life famine exposure and T2D in adulthood. Findings from these studies suggest that prenatal exposure to the famine may result in induction of persistent epigenetic changes that have adaptive significance in postnatal development but can predispose to metabolic disorders including T2D at the late stages of life. In this review, quasi-experimental data on the developmental programming of T2D are summarized and recent research findings on changes in DNA methylation that mediate these effects are discussed. PMID:28273874

Experimental economics' inconsistent ban on deception.

PubMed

Hersch, Gil

2015-08-01

According to what I call the 'argument from public bads', if a researcher deceived subjects in the past, there is a chance that subjects will discount the information that a subsequent researcher provides, thus compromising the validity of the subsequent researcher's experiment. While this argument is taken to justify an existing informal ban on explicit deception in experimental economics, it can also apply to implicit deception, yet implicit deception is not banned and is sometimes used in experimental economics. Thus, experimental economists are being inconsistent when they appeal to the argument from public bads to justify banning explicit deception but not implicit deception. Copyright © 2015 Elsevier Ltd. All rights reserved.

Study on strontium isotope abundance-ratio measurements by using a 13-MeV proton beam

NASA Astrophysics Data System (ADS)

Jeong, Cheol-Ki; Jang, Han; Lee, Goung-Jin

2016-09-01

The Rb-Sr dating method is used in dating Paleozoic and Precambrian rocks. This method measures the 87Rb and the 87Sr concentrations by using thermal ionization mass spectrometry (TIMS) [J. Hefne et al., Inter. J. Phys. Sci. 3(1), 28 (2008)]. In addition, it calculates the initial 87Sr/86Sr ratio to increase the reliability of Rb-Sr dating. In this study, the 87Sr/86Sr ratio was measured by using a 13-MeV proton accelerator. Proton kinetic energies are in the range of tens of megaelectronvolts, and protons have large absorption cross-sections for ( p, n) reactions with most substances. After absorbing a proton with such a high kinetic energy, an element is converted into a nuclide with its atomic number increased by one via nuclear transmutation. These nuclides usually have short half-lives and return to the original state through radioactive decay. When a strontium sample is irradiated with protons, nuclear transmutation occurs; thus, the strontium isotope present in the sample changes to a yttrium isotope, which is an activated radioisotope. Based on this, the 87Sr/86Sr ratio was calculated by analyzing the gamma-rays emitted by each yttrium isotope. The KIRAMS-13 cyclotron at the Cyclotron Center of Chosun University, where 13-MeV protons can be extracted, was utilized in our experiment. The 87Sr/86Sr isotope ratio was computed for samples irradiated with these protons, and the result was similar to the isotope ratio for the Standard Reference Material, i.e., 98.2 ± 3.4%. As part of the analysis, proton activation analyses were performed using 13-MeV protons, and the experimental results of this research suggest a possible approach for measuring the strontium-isotope abundance ratio of samples.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lane, Taylor; Parma, Edward J.

Delayed fission gamma-rays play an important role in determining the time dependent ioniz- ing dose for experiments in the central irradiation cavity of the Annular Core Research Reactor (ACRR). Delayed gamma-rays are produced from both fission product decay and from acti- vation of materials in the core, such as cladding and support structures. Knowing both the delayed gamma-ray emission rate and the time-dependent gamma-ray energy spectrum is nec- essary in order to properly determine the dose contributions from delayed fission gamma-rays. This information is especially important when attempting to deconvolute the time-dependent neutron, prompt gamma-ray, and delayed gamma-ray contribution tomore » the response of a diamond photo-conducting diode (PCD) or fission chamber in time frames of milliseconds to seconds following a reactor pulse. This work focused on investigating delayed gamma-ray character- istics produced from fission products from thermal, fast, and high energy fission of Th-232, U-233, U-235, U-238, and Pu-239. This work uses a modified version of CINDER2008, a transmutation code developed at Los Alamos National Laboratory, to model time and energy dependent photon characteristics due to fission. This modified code adds the capability to track photon-induced transmutations, photo-fission, and the subsequent radiation caused by fission products due to photo-fission. The data is compared against previous work done with SNL- modified CINDER2008 [ 1 ] and experimental data [ 2 , 3 ] and other published literature, includ- ing ENDF/B-VII.1 [ 4 ]. The ability to produce a high-fidelity (7,428 group) energy-dependent photon fluence at various times post-fission can improve the delayed photon characterization for radiation effects tests at research reactors, as well as other applications.« less

Combined Teaching Method: An Experimental Study

ERIC Educational Resources Information Center

Kolesnikova, Iryna V.

2016-01-01

The search for the best approach to business education has led educators and researchers to seek many different teaching strategies, ranging from the traditional teaching methods to various experimental approaches such as active learning techniques. The aim of this experimental study was to compare the effects of the traditional and combined…

Experimental demonstration of the anti-maser

NASA Astrophysics Data System (ADS)

Mazzocco, Anthony; Aviles, Michael; Andrews, Jim; Dawson, Nathan; Crescimanno, Michael

2012-10-01

We denote by ``anti-maser'' a coherent perfect absorption (CPA) process in the radio frequency domain. We demonstrate several experimental realizations of the anti-maser suitable for an advanced undergraduate laboratory. Students designed, assembled and tested these devices, as well as the inexpensive laboratory setup and experimental protocol for displaying various CPA phenomenon.

Great Basin Experimental Range: Annotated bibliography

Treesearch

E. Durant McArthur; Bryce A. Richardson; Stanley G. Kitchen

2013-01-01

This annotated bibliography documents the research that has been conducted on the Great Basin Experimental Range (GBER, also known as the Utah Experiment Station, Great Basin Station, the Great Basin Branch Experiment Station, Great Basin Experimental Center, and other similar name variants) over the 102 years of its existence. Entries were drawn from the original...

Medical experimentation in the elderly.

PubMed

Bernstein, J E; Nelson, F K

1975-07-01

Participation in human experimental research constitutes a major problem for the geriatric subject. Because there is a high incidence of noncontagious disease in the elderly, they are the group most useful for the study of new therapeutic agents or procedures. However, normal aging processes, often coupled with disease of the central nervous system, render elderly persons less able to comprehend the nature and risks of such studies. These factors permit easy exploitation of geriatric subjects in medical experimentation, with possible exposure to a significant risk of serious drug reactions and unnecessary hospitalization. Recent federal regulations have given "special protections" to children, prisoners, and the mentally infirm in experimental research, to guard against abuse of their human rights. A basic requirement is that informed consent be carefully obtained and documented. Such "special protections" should now be extended to geriatric subjects so that there will be no further exploitation in the course of valid clinical research.

Experimental verification of dynamic simulation

NASA Technical Reports Server (NTRS)

Yae, K. Harold; Hwang, Howyoung; Chern, Su-Tai

1989-01-01

The dynamics model here is a backhoe, which is a four degree of freedom manipulator from the dynamics standpoint. Two types of experiment are chosen that can also be simulated by a multibody dynamics simulation program. In the experiment, recorded were the configuration and force histories; that is, velocity and position, and force output and differential pressure change from the hydraulic cylinder, in the time domain. When the experimental force history is used as driving force in the simulation model, the forward dynamics simulation produces a corresponding configuration history. Then, the experimental configuration history is used in the inverse dynamics analysis to generate a corresponding force history. Therefore, two sets of configuration and force histories--one set from experiment, and the other from the simulation that is driven forward and backward with the experimental data--are compared in the time domain. More comparisons are made in regard to the effects of initial conditions, friction, and viscous damping.

Charge of the containerless experimentation in microgravity

NASA Technical Reports Server (NTRS)

Lee, Mark C.

1990-01-01

The experimentation was undertaken to study the elimination or reduction of surface contamination for which there is adequate Earth-based technology along with the reduction of dynamic nucleation for which there a paucity of reliable data. One objective is to delineate scientific justification of the U.S. Containerless Experimentation Program in Microgravity for the next decade and beyond. Another objective is for the guidance of NASA to define the next generation of containerless experimentation instruments in microgravity.

14 CFR 437.9 - Issuance of an experimental permit.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Issuance of an experimental permit. 437.9..., DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS General Information § 437.9 Issuance of an experimental permit. The FAA issues an experimental permit authorizing an unlimited number of launches or...

14 CFR 437.5 - Eligibility for an experimental permit.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Eligibility for an experimental permit. 437... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS General Information § 437.5 Eligibility for an experimental permit. The FAA will issue an experimental permit to a person to launch or...

14 CFR 437.5 - Eligibility for an experimental permit.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Eligibility for an experimental permit. 437... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS General Information § 437.5 Eligibility for an experimental permit. The FAA will issue an experimental permit to a person to launch or...

14 CFR 437.5 - Eligibility for an experimental permit.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Eligibility for an experimental permit. 437... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS General Information § 437.5 Eligibility for an experimental permit. The FAA will issue an experimental permit to a person to launch or...

14 CFR 437.9 - Issuance of an experimental permit.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Issuance of an experimental permit. 437.9..., DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS General Information § 437.9 Issuance of an experimental permit. The FAA issues an experimental permit authorizing an unlimited number of launches or...

14 CFR 437.5 - Eligibility for an experimental permit.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Eligibility for an experimental permit. 437... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS General Information § 437.5 Eligibility for an experimental permit. The FAA will issue an experimental permit to a person to launch or...

14 CFR 437.9 - Issuance of an experimental permit.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Issuance of an experimental permit. 437.9..., DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS General Information § 437.9 Issuance of an experimental permit. The FAA issues an experimental permit authorizing an unlimited number of launches or...

14 CFR 437.9 - Issuance of an experimental permit.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Issuance of an experimental permit. 437.9..., DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS General Information § 437.9 Issuance of an experimental permit. The FAA issues an experimental permit authorizing an unlimited number of launches or...

14 CFR 437.5 - Eligibility for an experimental permit.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Eligibility for an experimental permit. 437... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS General Information § 437.5 Eligibility for an experimental permit. The FAA will issue an experimental permit to a person to launch or...

14 CFR 437.9 - Issuance of an experimental permit.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Issuance of an experimental permit. 437.9..., DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS General Information § 437.9 Issuance of an experimental permit. The FAA issues an experimental permit authorizing an unlimited number of launches or...

Experimental validation of structural optimization methods

NASA Technical Reports Server (NTRS)

Adelman, Howard M.

1992-01-01

The topic of validating structural optimization methods by use of experimental results is addressed. The need for validating the methods as a way of effecting a greater and an accelerated acceptance of formal optimization methods by practicing engineering designers is described. The range of validation strategies is defined which includes comparison of optimization results with more traditional design approaches, establishing the accuracy of analyses used, and finally experimental validation of the optimization results. Examples of the use of experimental results to validate optimization techniques are described. The examples include experimental validation of the following: optimum design of a trussed beam; combined control-structure design of a cable-supported beam simulating an actively controlled space structure; minimum weight design of a beam with frequency constraints; minimization of the vibration response of helicopter rotor blade; minimum weight design of a turbine blade disk; aeroelastic optimization of an aircraft vertical fin; airfoil shape optimization for drag minimization; optimization of the shape of a hole in a plate for stress minimization; optimization to minimize beam dynamic response; and structural optimization of a low vibration helicopter rotor.

Experimental models of demyelination and remyelination.

PubMed

Torre-Fuentes, L; Moreno-Jiménez, L; Pytel, V; Matías-Guiu, J A; Gómez-Pinedo, U; Matías-Guiu, J

2017-08-29

Experimental animal models constitute a useful tool to deepen our knowledge of central nervous system disorders. In the case of multiple sclerosis, however, there is no such specific model able to provide an overview of the disease; multiple models covering the different pathophysiological features of the disease are therefore necessary. We reviewed the different in vitro and in vivo experimental models used in multiple sclerosis research. Concerning in vitro models, we analysed cell cultures and slice models. As for in vivo models, we examined such models of autoimmunity and inflammation as experimental allergic encephalitis in different animals and virus-induced demyelinating diseases. Furthermore, we analysed models of demyelination and remyelination, including chemical lesions caused by cuprizone, lysolecithin, and ethidium bromide; zebrafish; and transgenic models. Experimental models provide a deeper understanding of the different pathogenic mechanisms involved in multiple sclerosis. Choosing one model or another depends on the specific aims of the study. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

A Robust Adaptive Autonomous Approach to Optimal Experimental Design

NASA Astrophysics Data System (ADS)

Gu, Hairong

Experimentation is the fundamental tool of scientific inquiries to understand the laws governing the nature and human behaviors. Many complex real-world experimental scenarios, particularly in quest of prediction accuracy, often encounter difficulties to conduct experiments using an existing experimental procedure for the following two reasons. First, the existing experimental procedures require a parametric model to serve as the proxy of the latent data structure or data-generating mechanism at the beginning of an experiment. However, for those experimental scenarios of concern, a sound model is often unavailable before an experiment. Second, those experimental scenarios usually contain a large number of design variables, which potentially leads to a lengthy and costly data collection cycle. Incompetently, the existing experimental procedures are unable to optimize large-scale experiments so as to minimize the experimental length and cost. Facing the two challenges in those experimental scenarios, the aim of the present study is to develop a new experimental procedure that allows an experiment to be conducted without the assumption of a parametric model while still achieving satisfactory prediction, and performs optimization of experimental designs to improve the efficiency of an experiment. The new experimental procedure developed in the present study is named robust adaptive autonomous system (RAAS). RAAS is a procedure for sequential experiments composed of multiple experimental trials, which performs function estimation, variable selection, reverse prediction and design optimization on each trial. Directly addressing the challenges in those experimental scenarios of concern, function estimation and variable selection are performed by data-driven modeling methods to generate a predictive model from data collected during the course of an experiment, thus exempting the requirement of a parametric model at the beginning of an experiment; design optimization is

Chemotherapy of experimental bovine petechial fever.

PubMed

Snodgrass, D R

1976-01-01

A dithiosemicarbazone was compared with two tetracycline formulations in the treatment of bovine petechial fever (BPF) in experimentally infected sheep, and was then used to treat the disease in experimental cattle. The dithiosemicarbazone was found to be more efficacious than either of the other two drugs in treating ovine BPF, and also to be effective against BPF in cattle.

The Stephen F. Austin Experimental Forest

Treesearch

Cary C. Russell; Ronald E. Thill; David L. Kulhavy

2002-01-01

On December 14, 1944, the Seventy-Eighth United States Congress passed a bill that authorized the transfer of 2,560 acres in Nacogdoches County, Texas, to the research branch of the United States Forest Service (USFS). This land became the Stephen F. Austin Experimental Forest (SFAEF) on September 19. 1945. One of eighty-one federal experimental forests and ranges...

Experimental Influence Coefficients and Vibration Modes

NASA Technical Reports Server (NTRS)

Weidman, Deene J.; Kordes, Eldon E.

1959-01-01

Test results are presented for both symmetrical and antisymmetrical static loading of a wing model mounted on a three-point support system. The first six free-free vibration modes were determined experimentally. A comparison is made of the symmetrical nodal patterns and frequencies with the symmetrical nodal patterns and frequencies calculated from the experimental influence coefficients.

Leader Positivity and Follower Creativity: An Experimental Analysis

ERIC Educational Resources Information Center

Avey, James B.; Richmond, F. Lynn; Nixon, Don R.

2012-01-01

Using an experimental research design, 191 working adults were randomly assigned to two experimental conditions in order to test a theoretical model linking leader and follower positive psychological capital (PsyCap). Multiple methods were used to gather information from the participants. We found when leader PsyCap was manipulated experimentally,…

Storming a Citadel: Mathematical Theory and Experimental Practice

NASA Astrophysics Data System (ADS)

Sichau, Christian

2006-09-01

Based upon a comparison of the viscosity experiments of James Clerk Maxwell (1831 1879) and Oskar Emil Meyer (1834 1909) in the 1860s, I argue that mathematical theory plays a significant role in both aspects of experimental practice, the design and construction of an experimental apparatus and the transformation of the observed experimental data into the value of a physical quantity. I argue further that Maxwell’s and Meyer’s evaluation of each other’s theoretical and experimental work depended significantly on the mathematical tools they employed in their theories.

Rheology of welding: experimental constraints

NASA Astrophysics Data System (ADS)

Quane, S. L.; Russell, J. K.; Kennedy, L. A.

2003-04-01

The rheological behavior of pyroclastic deposits during welding is incompletely understood and is based on a surprisingly small number of experimental studies. Previous pioneering experimental studies were done on small (1 cm thick) samples of ash/crystal mixtures under constant load. They established minimum welding temperatures between 600 and 700^oC under loads of 0.7 MPa (˜40 m of ignimbrite) to 3.6 MPa (˜250 m depth of ignimbrite). However, these data are neither sufficiently comprehensive nor coherent enough to fully describe the rheology of pyroclastic mixtures. In addition, previous studies did not examine the microstructural and geometric changes associated with welding compaction. Our goal is to provide accurate and comprehensive constitutive relationships between material properties, temperature, load and strain rate for pyroclastic material undergoing welding. Here we present results from a newly designed experimental apparatus. The experimental apparatus consists of a LoadTrac II fully automated uniaxial compression load frame manufactured by Geocomp Corporation. The load frame has a built in displacement transducer and can run both constant strain rate (10-6 to 0.25 cm/s) and constant load (up to 1150 kg) tests to a maximum displacement of 7.5 cm. The sample assembly comprises 5 cm diameter cylindrical upper and lower pistons (insulating ceramic with steel conductive ends) housed in a copper jacket. Samples are 5 cm diameter cores and can vary in length from 1 to 15 cm depending on experimental needs. A fiber insulated tube furnace capable of reaching temperatures ≈1000^oC surrounds the sample assembly. Temperature is measured using a thermocouple located inside the sample through the bottom piston; the furnace controller is capable of maintaining temperature fluctuations to <5^oC. Deformation experiments are performed on pre-fabricated cylinders of soda-lime glass beads and rhyolitic volcanic ash, as well as, cores of pumiceous rhyodacite

Experimental temporal quantum steering

PubMed Central

Bartkiewicz, Karol; Černoch, Antonín; Lemr, Karel; Miranowicz, Adam; Nori, Franco

2016-01-01

Temporal steering is a form of temporal correlation between the initial and final state of a quantum system. It is a temporal analogue of the famous Einstein-Podolsky-Rosen (spatial) steering. We demonstrate, by measuring the photon polarization, that temporal steering allows two parties to verify if they have been interacting with the same particle, even if they have no information about what happened with the particle in between the measurements. This is the first experimental study of temporal steering. We also performed experimental tests, based on the violation of temporal steering inequalities, of the security of two quantum key distribution protocols against individual attacks. Thus, these results can lead to applications for secure quantum communications and quantum engineering. PMID:27901121

16 CFR § 1702.9 - Relevant experimental data.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Relevant experimental data. § 1702.9...; PETITION PROCEDURES AND REQUIREMENTS § 1702.9 Relevant experimental data. Experimental data are generated... true of those substances which are not normally intended to be used in or on the human body or animal...

The benefits of an advanced fast reactor fuel cycle for plutonium management

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hannum, W.H.; McFarlane, H.F.; Wade, D.C.

1996-12-31

The United States has no program to investigate advanced nuclear fuel cycles for the large-scale consumption of plutonium from military and civilian sources. The official U.S. position has been to focus on means to bury spent nuclear fuel from civilian reactors and to achieve the spent fuel standard for excess separated plutonium, which is considered by policy makers to be an urgent international priority. Recently, the National Research Council published a long awaited report on its study of potential separation and transmutation technologies (STATS), which concluded that in the nuclear energy phase-out scenario that they evaluated, transmutation of plutonium andmore » long-lived radioisotopes would not be worth the cost. However, at the American Nuclear Society Annual Meeting in June, 1996, the STATS panelists endorsed further study of partitioning to achieve superior waste forms for burial, and suggested that any further consideration of transmutation should be in the context of energy production, not of waste management. 2048 The U.S. Department of Energy (DOE) has an active program for the short-term disposition of excess fissile material and a `focus area` for safe, secure stabilization, storage and disposition of plutonium, but has no current programs for fast reactor development. Nevertheless, sufficient data exist to identify the potential advantages of an advanced fast reactor metallic fuel cycle for the long-term management of plutonium. Advantages are discussed.« less

Gold nanoparticles production using reactor and cyclotron based methods in assessment of (196,198)Au production yields by (197)Au neutron absorption for therapeutic purposes.

PubMed

Khorshidi, Abdollah

2016-11-01

Medical nano-gold radioisotopes is produced regularly using high-flux nuclear reactors, and an accelerator-driven neutron activator can turn out higher yield of (197)Au(n,γ)(196,198)Au reactions. Here, nano-gold production via radiative/neutron capture was investigated using irradiated Tehran Research Reactor flux and also simulated proton beam of Karaj cyclotron in Iran. (197)Au nano-solution, including 20nm shaped spherical gold and water, was irradiated under Tehran reactor flux at 2.5E+13n/cm(2)/s for (196,198)Au activity and production yield estimations. Meanwhile, the yield was examined using 30MeV proton beam of Karaj cyclotron via simulated new neutron activator containing beryllium target, bismuth moderator around the target, and also PbF2 reflector enclosed the moderator region. Transmutation in (197)Au nano-solution samples were explored at 15 and 25cm distances from the target. The neutron flux behavior inside the water and bismuth moderators was investigated for nano-gold particles transmutation. The transport of fast neutrons inside bismuth material as heavy nuclei with a lesser lethargy can be contributed in enhanced nano-gold transmutation with long duration time than the water moderator in reactor-based method. Cyclotron-driven production of βeta-emitting radioisotopes for brachytherapy applications can complete the nano-gold production technology as a safer approach as compared to the reactor-based method. Copyright © 2016 Elsevier B.V. All rights reserved.

Role of ADS in the back-end of the fuel cycle strategies and associated design activities: The case of Japan

NASA Astrophysics Data System (ADS)

Oigawa, Hiroyuki; Tsujimoto, Kazufumi; Nishihara, Kenji; Sugawara, Takanori; Kurata, Yuji; Takei, Hayanori; Saito, Shigeru; Sasa, Toshinobu; Obayashi, Hironari

2011-08-01

Reduction of burden caused by radioactive waste management is one of the most critical issues for the sustainable utilization of nuclear power. The Partitioning and Transmutation (P&T) technology provides the possibility to reduce the amount of the radiotoxic inventory of the high-level radioactive waste (HLW) dramatically and to extend the repository capacity. The accelerator-driven system (ADS) is regarded as a powerful tool to effectively transmute minor actinides (MAs) in the "double-strata" fuel cycle strategy. The ADS has a potential to flexibly manage MA in the transient phase from light water reactors (LWRs) to fast breeder reactors (FBRs), and can co-exist with FBR symbiotically and complementarily to enhance the reliability and the safety of the commercial FBR cycle. The concept of ADS in JAEA is a lead-bismuth eutectic (LBE) cooled, tank-type subcritical reactor with the power of 800 MWth driven by a 30 MW superconducting LINAC. By such an ADS, 250 kg of MA can be transmuted annually, which corresponds to the amount of MA produced in 10 units of LWR with 1 GWe. The design study was performed mainly for the subcritical reactor and the spallation target with a beam window. In Japan, Atomic Energy Commission (AEC) has implemented the check and review (C&R) on P&T technology from 2008 to 2009. In the C&R, the benefit of P&T technology, the current status of the R&D, and the way forward to promote it were discussed.

Alchemy--A History of Early Technology.

ERIC Educational Resources Information Center

Pollard, A. M.

1988-01-01

Reviews the history of alchemy including personalities and methods. Discusses the philosophy associated with various early chemists and alchemists. Attempts to show that it was not unreasonable for ancient alchemists to believe in the possibility of transmutation. (CW)

Qualitative tools and experimental philosophy

PubMed Central

Andow, James

2016-01-01

Abstract Experimental philosophy brings empirical methods to philosophy. These methods are used to probe how people think about philosophically interesting things such as knowledge, morality, and freedom. This paper explores the contribution that qualitative methods have to make in this enterprise. I argue that qualitative methods have the potential to make a much greater contribution than they have so far. Along the way, I acknowledge a few types of resistance that proponents of qualitative methods in experimental philosophy might encounter, and provide reasons to think they are ill-founded. PMID:28392629

Qualitative tools and experimental philosophy.

PubMed

Andow, James

2016-11-16

Experimental philosophy brings empirical methods to philosophy. These methods are used to probe how people think about philosophically interesting things such as knowledge, morality, and freedom. This paper explores the contribution that qualitative methods have to make in this enterprise. I argue that qualitative methods have the potential to make a much greater contribution than they have so far. Along the way, I acknowledge a few types of resistance that proponents of qualitative methods in experimental philosophy might encounter, and provide reasons to think they are ill-founded.

Experimental toxicology: Issues of statistics, experimental design, and replication.

PubMed

Briner, Wayne; Kirwan, Jeral

2017-01-01

The difficulty of replicating experiments has drawn considerable attention. Issues with replication occur for a variety of reasons ranging from experimental design to laboratory errors to inappropriate statistical analysis. Here we review a variety of guidelines for statistical analysis, design, and execution of experiments in toxicology. In general, replication can be improved by using hypothesis driven experiments with adequate sample sizes, randomization, and blind data collection techniques. Copyright © 2016 Elsevier B.V. All rights reserved.

Optimal Experimental Design for Model Discrimination

PubMed Central

Myung, Jay I.; Pitt, Mark A.

2009-01-01

Models of a psychological process can be difficult to discriminate experimentally because it is not easy to determine the values of the critical design variables (e.g., presentation schedule, stimulus structure) that will be most informative in differentiating them. Recent developments in sampling-based search methods in statistics make it possible to determine these values, and thereby identify an optimal experimental design. After describing the method, it is demonstrated in two content areas in cognitive psychology in which models are highly competitive: retention (i.e., forgetting) and categorization. The optimal design is compared with the quality of designs used in the literature. The findings demonstrate that design optimization has the potential to increase the informativeness of the experimental method. PMID:19618983

Designing an Experimental "Accident"

ERIC Educational Resources Information Center

Picker, Lester

1974-01-01

Describes an experimental "accident" that resulted in much student learning, seeks help in the identification of nematodes, and suggests biology teachers introduce similar accidents into their teaching to stimulate student interest. (PEB)

Preface

NASA Astrophysics Data System (ADS)

Kowalska, Magdalena; Błaszczak, Zdzislaw

2017-11-01

It is with great pleasure that we are presenting the subsequent volume of the International Poznan Workshop proceedings. The conferences of this cycle have been since the beginning devoted to laser light interaction with atomic nuclei and since more recently also to the applications of ion-storage devices. The first edition entitled "Laser Spectroscopy of Atomic Nuclei" took place in Dubna in December 1990, and since then the subsequent conferences have been held every two to three years in Poznan, where they have been jointly organized by the Faculty of Physics at the Adam Mickiewicz University (Poznan) and the Flerov Laboratory of Nuclear Reactions at the Joint Institute of Nuclear Research (Dubna). The conferences have enjoyed increasing popularity and have attracted increasing numbers of specialists from a number of research institutions engaged in laser spectroscopy of radioactive and other exotic (e.g. anti-) atomic nuclei and related instruments. Over the years the workshops have gained a reputation of presenting research of a high scientific level and having impact on the directions of future studies. The 2016 workshop on the Application of Lasers and Storage Devices in Atomic Nuclei Research has been already the 10th edition and it was a pleasure to see that the event was thriving and the participants were enjoying it in all fronts. Around 100 scientists met on May 16 -19 in Poznan for the 4-day event. They were even more international than in the previous edition, representing institutes in Europe, North America, Japan, and even Australia. Many have returned to Poznan, but there were also new faces, especially among the younger participants. It was great to see the leaders in their topics discussing physics, but not only, with PhD students and starting post-docs. More than sixty talks were delivered, reflecting well the state-of-the art in the covered fields which were all related to the techniques, experimental results and theory connected to lasers and

Woodward Effect Experimental Verifications

NASA Astrophysics Data System (ADS)

March, Paul

2004-02-01

The work of J. F. Woodward (1990 1996a; 1996b; 1998; 2002a; 2002b; 2004) on the existence of ``mass fluctuations'' and their use in exotic propulsion schemes was examined for possible application in improving space flight propulsion and power generation. Woodward examined Einstein's General Relativity Theory (GRT) and assumed that if the strong Machian interpretation of GRT as well as gravitational / inertia like Wheeler-Feynman radiation reaction forces hold, then when an elementary particle is accelerated through a potential gradient, its rest mass should fluctuate around its mean value during its acceleration. Woodward also used GRT to clarify the precise experimental conditions necessary for observing and exploiting these mass fluctuations or ``Woodward effect'' (W-E). Later, in collaboration with his ex-graduate student T. Mahood, they also pushed the experimental verification boundaries of these proposals. If these purported mass fluctuations occur as Woodward claims, and his assumption that gravity and inertia are both byproducts of the same GRT based phenomenon per Mach's Principle is correct, then many innovative applications such as propellantless propulsion and gravitational exotic matter generators may be feasible. This paper examines the reality of mass fluctuations and the feasibility of using the W-E to design propellantless propulsion devices in the near to mid-term future. The latest experimental results, utilizing MHD-like force rectification systems, will also be presented.

The 1986 Get Away Special Experimenter's Symposium

NASA Technical Reports Server (NTRS)

Thomas, Lawrence R. (Editor); Mosier, Frances L. (Editor)

1987-01-01

The 1986 Get Away Special (GAS) Experimenter's Symposium will provide a formal opportunity for GAS Experimenter's to share the results of their projects. The focus of this symposium is on payloads that will be flown in the future.

Using experimental design to define boundary manikins.

PubMed

Bertilsson, Erik; Högberg, Dan; Hanson, Lars

2012-01-01

When evaluating human-machine interaction it is central to consider anthropometric diversity to ensure intended accommodation levels. A well-known method is the use of boundary cases where manikins with extreme but likely measurement combinations are derived by mathematical treatment of anthropometric data. The supposition by that method is that the use of these manikins will facilitate accommodation of the expected part of the total, less extreme, population. In literature sources there are differences in how many and in what way these manikins should be defined. A similar field to the boundary case method is the use of experimental design in where relationships between affecting factors of a process is studied by a systematic approach. This paper examines the possibilities to adopt methodology used in experimental design to define a group of manikins. Different experimental designs were adopted to be used together with a confidence region and its axes. The result from the study shows that it is possible to adapt the methodology of experimental design when creating groups of manikins. The size of these groups of manikins depends heavily on the number of key measurements but also on the type of chosen experimental design.

Experimental preparation and verification of quantum money

NASA Astrophysics Data System (ADS)

Guan, Jian-Yu; Arrazola, Juan Miguel; Amiri, Ryan; Zhang, Weijun; Li, Hao; You, Lixing; Wang, Zhen; Zhang, Qiang; Pan, Jian-Wei

2018-03-01

A quantum money scheme enables a trusted bank to provide untrusted users with verifiable quantum banknotes that cannot be forged. In this work, we report a proof-of-principle experimental demonstration of the preparation and verification of unforgeable quantum banknotes. We employ a security analysis that takes experimental imperfections fully into account. We measure a total of 3.6 ×106 states in one verification round, limiting the forging probability to 10-7 based on the security analysis. Our results demonstrate the feasibility of preparing and verifying quantum banknotes using currently available experimental techniques.

Family Environmental and Genetic Influences on Children's Future Chemical Dependency.

ERIC Educational Resources Information Center

Kumpfer, Karol L.; DeMarsh, Joseph

1985-01-01

Discusses the following in relation to their predictability to future drug abuse in youth: (1) susceptibility of children of chemically dependent parents; (2) genetic transmutation; (3) family structure and management; (4) socialization; and (5) cognitive family characteristics. (Author/LHW)

Multiplicity and entropy scaling of medium-energy protons emitted in relativistic heavy-ion collisions

NASA Astrophysics Data System (ADS)

Abdelsalam, A.; Kamel, S.; Hafiz, M. E.

2015-10-01

The behavior and the properties of medium-energy protons with kinetic energies in the range 26 - 400 MeV is derived from measurements of the particle yields and spectra in the final state of relativistic heavy-ion collisions (16O-AgBr interactions at 60 A and 200 A GeV and 32S-AgBr interactions at 3.7 A and 200 A GeV) and their interpretation in terms of the higher order moments. The multiplicity distributions have been fitted well with the Gaussian distribution function. The data are also compared with the predictions of the modified FRITIOF model, showing that the FRITIOF model does not reproduce the trend and the magnitude of the data. Measurements of the ratio of the variance to the mean show that the production of target fragments at high energies cannot be considered as a statistically independent process. However, the deviation of each multiplicity distribution from a Poisson law provides evidence for correlations. The KNO scaling behavior of two types of scaling (Koba-Nielsen-Olesen (KNO) scaling and Hegyi scaling) functions in terms of the multiplicity distribution is investigated. A simplified universal function has been used in each scaling to display the experimental data. An examination of the relationship between the entropy, the average multiplicity, and the KNO function is performed. Entropy production and subsequent scaling in nucleus-nucleus collisions are carried out by analyzing the experimental data over a wide energy range (Dubna and SPS). Interestingly, the data points corresponding to various energies overlap and fall on a single curve, indicating the presence of a kind of entropy scaling.

Moriond QCD 2013 Experimental Summary

DOE Office of Scientific and Technical Information (OSTI.GOV)

Denisov, Dmitri

2013-06-28

The article presents experimental highlights of Moriond 2013 QCD conference. This was fantastic conference and the first Moriond QCD since the discovery of the Higgs boson. Many new results about its properties have been presented at the conference with Higgs-like particle becoming a Higgs as it properties match expected for the Higgs boson pretty well. There were many new results presented in all experimental areas including QCD, elecroweak, studies of the top, bottom and charm quarks, searches for physics beyond Standard Model as well as studies of the heavy ion collisions. 56 experimental talks have been presented at the conferencemore » and it is impossible to cover each result in the summary, so highlights are limited to what I was able to present in my summary talk presented on March 16 2013. The proceedings of the conference cover in depth all talks presented and I urge you to get familiar with all of them. Theoretical Summary of the conference was given by Michelangelo Mangano, so theory talks are not covered in the article.« less

Students' views about the nature of experimental physics

NASA Astrophysics Data System (ADS)

Wilcox, Bethany R.; Lewandowski, H. J.

2017-12-01

The physics community explores and explains the physical world through a blend of theoretical and experimental studies. The future of physics as a discipline depends on training of students in both the theoretical and experimental aspects of the field. However, while student learning within lecture courses has been the subject of extensive research, lab courses remain relatively under-studied. In particular, there is little, if any, data available that address the effectiveness of physics lab courses at encouraging students to recognize the nature and importance of experimental physics within the discipline as a whole. To address this gap, we present the first large-scale, national study (Ninstitutions=75 and Nstudents=7167 ) of undergraduate physics lab courses through analysis of students' responses to a research-validated assessment designed to investigate students' beliefs about the nature of experimental physics. We find that students often enter and leave physics lab courses with ideas about experimental physics as practiced in their courses that are inconsistent with the views of practicing experimental physicists, and this trend holds at both the introductory and upper-division levels. Despite this inconsistency, we find that both introductory and upper-division students are able to accurately predict the expertlike response even in cases where their views about experimentation in their lab courses disagree. These finding have implications for the recruitment, retention, and adequate preparation of students in physics.

An Experimental Analysis of Another Privacy

ERIC Educational Resources Information Center

Okouchi, Hiroto

2006-01-01

The present article discusses how events outside a subject's skin and not accessible to another subject but to an experimenter may contribute to experimental analyses of private events. Of 16 undergraduates, 8, referred to as instructors, first learned conditional discriminations (i.e., B1C1, B2C2, B3C3, and B4C4) in a standard matching-to-sample…

Maybeso Experimental Forest.

Treesearch

Valerie Rapp

2004-01-01

The Maybeso Experimental Forest is in southeast Alaska within the Tongass National Forest, the largest national forest in the United States and home to the Northern Hemi-sphere's largest temperate rain forest. Located about 42 miles west of Ketchikan, Alaska, it is on Prince of Wales Island, the largest island of the Alexander Archipelago and the third largest...

Kane Experimental Forest

Treesearch

Northeastern Research Station

1999-01-01

The 1,737 acres of forest land that comprise the Kane Experimental Forest (KEF), were originally part of the Allegheny National Forest. On March 23, 1932, the land was formally dedicated to research use for the Allegheny Forest Experiment Station (now the Northeastern Research Station). The KEF was established to promote the study of the unglaciated portion of the...

Bartlett Experimental Forest

Treesearch

Jane Gamal-Eldin

1998-01-01

The Bartlett Experimental Forest is a field laboratory for research on the ecology and management of northern forest ecosystems. Research on the Bartlett includes: 1) extensive investigations on structure and dynamics of forests at several levels, and developing management alternatives to reflect an array of values and benefits sought by users of forest lands, 2) a...

Hadron Physics at the Charm and Bottom Thresholds and Other Novel QCD Physics Topics at the NICA Accelerator Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brodsky, Stanley J.; /SLAC

The NICA collider project at the Joint Institute for Nuclear Research in Dubna will have the capability of colliding protons, polarized deuterons, and nuclei at an effective nucleon-nucleon center-of mass energy in the range {radical}s{sub NN} = 4 to 11 GeV. I briefly survey a number of novel hadron physics processes which can be investigated at the NICA collider. The topics include the formation of exotic heavy quark resonances near the charm and bottom thresholds, intrinsic strangeness, charm, and bottom phenomena, hidden-color degrees of freedom in nuclei, color transparency, single-spin asymmetries, the RHIC baryon anomaly, and non-universal antishadowing.

Hadron rapidity spectra within a hybrid model

NASA Astrophysics Data System (ADS)

Khvorostukhin, A. S.; Toneev, V. D.

2017-01-01

A 2-stage hybrid model is proposed that joins the fast initial state of interaction, described by the hadron string dynamics (HSD) model, to subsequent evolution of the expanding system at the second stage, treated within ideal hydrodynamics. The developed hybrid model is assigned to describe heavy-ion collisions in the energy range of the NICA collider under construction in Dubna. Generally, the model is in reasonable agreement with the available data on proton rapidity spectra. However, reproducing proton rapidity spectra, our hybrid model cannot describe the rapidity distributions of pions. The model should be improved by taking into consideration viscosity effects at the hydrodynamical stage of system evolution.

Dosimetry measurements using Timepix in mixed radiation fields induced by heavy ions; comparison with standard dosimetry methods

PubMed Central

Ploc, Ondrej; Kubancak, Jan; Sihver, Lembit; Uchihori, Yukio; Jakubek, Jan; Ambrozova, Iva; Molokanov, Alexander; Pinsky, Lawrence

2014-01-01

Objective of our research was to explore capabilities of Timepix for its use as a single dosemeter and LET spectrometer in mixed radiation fields created by heavy ions. We exposed it to radiation field (i) at heavy ion beams at HIMAC, Chiba, Japan, (ii) in the CERN's high-energy reference field (CERF) facility at Geneva, France/Switzerland, (iii) in the exposure room of the proton therapy laboratory at JINR, Dubna, Russia, and (iv) onboard aircraft. We compared the absolute values of dosimetric quantities obtained with Timepix and with other dosemeters and spectrometers like tissue-equivalent proportional counter (TEPC) Hawk, silicon detector Liulin, and track-etched detectors (TEDs).

LEPER: Library of Experimental PhasE Relations

NASA Astrophysics Data System (ADS)

Davis, F.; Gordon, S.; Mukherjee, S.; Hirschmann, M.; Ghiorso, M.

2006-12-01

The Library of Experimental PhasE Relations (LEPER) seeks to compile published experimental determinations of magmatic phase equilibria and provide those data on the web with a searchable and downloadable interface. Compiled experimental data include the conditions and durations of experiments, the bulk compositions of experimental charges, and the identity, compositions and proportions of phases observed, and, where available, estimates of experimental and analytical uncertainties. Also included are metadata such as the type of experimental device, capsule material, and method(s) of quantitative analysis. The database may be of use to practicing experimentalists as well as the wider Earth science community. Experimentalists may find the data useful for planning new experiments and will easily be able to compare their results to the full body of previous experimentnal data. Geologists may use LEPER to compare rocks sampled in the field with experiments performed on similar bulk composition or with experiments that produced similar-composition product phases. Modelers may use LEPER to parameterize partial melting of various lithologies. One motivation for compiling LEPER is for calibration of updated and revised versions of MELTS, however, it is hoped that the availability of LEPER will facilitate formulation and calibration of additional thermodynamic or empirical models of magmatic phase relations and phase equilibria, geothermometers and more. Data entry for LEPER is occuring presently: As of August, 2006, >6200 experiments have been entered, chiefly from work published between 1997 and 2005. A prototype web interface has been written and beta release on the web is anticipated in Fall, 2006. Eventually, experimentalists will be able to submit their new experimental data to the database via the web. At present, the database contains only data pertaining to the phase equilibria of silicate melts, but extension to other experimental data involving other fluids or

Wundt, Völkerpsychologie, and experimental social psychology.

PubMed

Greenwood, John D

2003-02-01

Wilhelm Wundt distinguished between "experimental psychology" and Volkerpsychologie. It is often claimed that Wundt maintained that social psychological phenomena, the subject matter of Völkerpsychologie, could not be investigated experimentally but must be explored via comparative-historical methods. In this article it is argued that it is doubtful if many of the passages usually cited as evidence that Wundt held such a view actually such such a view. It is also argued that if Wundt did hold such a view, it was inconsistent with his own general theoretical position and methodological practice. It is suggested that it is anachronistic to attribute such a view to Wundt, because he appears to have had little interest in the experimental analysis of the synchronic social dynamics of psychological processes. Most of Wundt's arguments about the inappropriateness of experimentation were directed against the introspective analysis of diachronic historical processes.

Research Directions for Cyber Experimentation: Workshop Discussion Analysis.

DOE Office of Scientific and Technical Information (OSTI.GOV)

DeWaard, Elizabeth; Deccio, Casey; Fritz, David Jakob

Sandia National Laboratories hosted a workshop on August 11, 2017 entitled "Research Directions for Cyber Experimentation," which focused on identifying and addressing research gaps within the field of cyber experimentation , particularly emulation testbeds . This report mainly documents the discussion toward the end of the workshop, which included research gaps such as developing a sustainable research infrastructure, exp anding cyber experimentation, and making the field more accessible to subject matter experts who may not have a background in computer science . Other gaps include methodologies for rigorous experimentation, validation, and uncertainty quantification, which , if addressed, also have themore » potential to bridge the gap between cyber experimentation and cyber engineering. Workshop attendees presented various ways to overcome these research gaps, however the main conclusion for overcoming these gaps is better commun ication through increased workshops, conferences, email lists, and slack chann els, among other opportunities.« less

New experimental techniques for solar cells

NASA Technical Reports Server (NTRS)

Lenk, R.

1993-01-01

Solar cell capacitance has special importance for an array controlled by shunting. Experimental measurements of solar cell capacitance in the past have shown disagreements of orders of magnitude. Correct measurement technique depends on maintaining the excitation voltage less than the thermal voltage. Two different experimental methods are shown to match theory well, and two effective capacitances are defined for quantifying the effect of the solar cell capacitance on the shunting system.

Rapidity distributions of hadrons in the HydHSD hybrid model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khvorostukhin, A. S., E-mail: hvorost@theor.jinr.ru; Toneev, V. D.

2017-03-15

A multistage hybrid model intended for describing heavy-ion interactions in the energy region of the NICA collider under construction in Dubna is proposed. The model combines the initial, fast, interaction stage described by the model of hadron string dynamics (HSD) and the subsequent evolution that the expanding system formed at the first stage experiences at the second stage and which one treats on the basis of ideal hydrodynamics; after the completion of the second stage, the particles involved may still undergo rescattering (third interaction stage). The model admits three freeze-out scenarios: isochronous, isothermal, and isoenergetic. Generally, the HydHSD hybrid modelmore » developed in the present study provides fairly good agreement with available experimental data on proton rapidity spectra. It is shown that, within this hybrid model, the two-humped structure of proton rapidity distributions can be obtained either by increasing the freeze-out temperature and energy density or by more lately going over to the hydrodynamic stage. Although the proposed hybrid model reproduces rapidity spectra of protons, it is unable to describe rapidity distributions of pions, systematically underestimating their yield. It is necessary to refine the model by including viscosity effects at the hydrodynamic stage of evolution of the system and by considering in more detail the third interaction stage.« less

MEXnICA, Mexican group in the MPD-NICA experiment at JINR

NASA Astrophysics Data System (ADS)

Rodríguez Cahuantzi, M.; MEXnICA Group

2017-10-01

The Nuclotron Ion Collider fAcility (NICA) accelerator complex is currently under construction at the Joint Institute for Nuclear Research (JINR) laboratory located in the city of Dubna in the Russian Federation. The main goal of NICA is to collide heavy ion nuclei to study the properties of the phase diagram of strongly interacting matter at high baryon density. In this accelerator complex, two big particle detectors are planned to be installed: Spin Physics Detector (SPD) and Multi-Purpose Detector (MPD). At the design luminosity, the event rate in the MPD interaction region is about 6 kHz; the total charged particle multiplicity would exceeds 1000 in the most central Au+Au collisions at \\sqrt{{sNN}} = 11 {{GeV}}. Since the middle of 2016 a group of researchers and students from Mexican institutions was formed (MEXnICA). The main goal of the MEXnICA group is to collaborate in the experimental efforts of MPD-NICA proposing a BEam-BEam counter detector which we called BEBE. In this written general aspects of MPD-NICA detector and BEBE are discussed. This material was shown in a contributed talk given at the XXXI Annual Meeting of the Mexican Division of Particles and Fields held in the Physics Department of CINVESTAV located in Mexico City during the last week of May 2017.

Rational choice, neuroeconomy and mixed emotions.

PubMed

Livet, Pierre

2010-01-27

Experimental psychology has shown differences between predictions of theory of decision and human choices. Emotions like regret can partly explain these differences. Neuroimagery used in combination with behavioural economics (neuroeconomics) has been used in order to try to disentangle the different emotional and rational factors (regret, rejoicing, reward, costs, uncertainty, trade-off between positive and negative aspects of different options). Emotions then appear as much more complex and mixed affective states than usually assumed. Not only might we feel a positive affect in punishing unfair partners, but mixed emotions can, for example, combine transmutation of previous anxiety into relief and elation by comparison with another less exciting option (elating relief). At the level of complexity of these mixed emotions--which we formally represent by comparisons between 'unexpected utilities' and expected ones--the main biases that Kahnemann and Tversky have shown can be explained. In spite of the complexity of these mixed emotions, some of these hypotheses might be partially tested by brain imagery.

Multiple ion beam irradiation for the study of radiation damage in materials

NASA Astrophysics Data System (ADS)

Taller, Stephen; Woodley, David; Getto, Elizabeth; Monterrosa, Anthony M.; Jiao, Zhijie; Toader, Ovidiu; Naab, Fabian; Kubley, Thomas; Dwaraknath, Shyam; Was, Gary S.

2017-12-01

The effects of transmutation produced helium and hydrogen must be included in ion irradiation experiments to emulate the microstructure of reactor irradiated materials. Descriptions of the criteria and systems necessary for multiple ion beam irradiation are presented and validated experimentally. A calculation methodology was developed to quantify the spatial distribution, implantation depth and amount of energy-degraded and implanted light ions when using a thin foil rotating energy degrader during multi-ion beam irradiation. A dual ion implantation using 1.34 MeV Fe+ ions and energy-degraded D+ ions was conducted on single crystal silicon to benchmark the dosimetry used for multi-ion beam irradiations. Secondary Ion Mass Spectroscopy (SIMS) analysis showed good agreement with calculations of the peak implantation depth and the total amount of iron and deuterium implanted. The results establish the capability to quantify the ion fluence from both heavy ion beams and energy-degraded light ion beams for the purpose of using multi-ion beam irradiations to emulate reactor irradiated microstructures.

Rational choice, neuroeconomy and mixed emotions

PubMed Central

Livet, Pierre

2010-01-01

Experimental psychology has shown differences between predictions of theory of decision and human choices. Emotions like regret can partly explain these differences. Neuroimagery used in combination with behavioural economics (neuroeconomics) has been used in order to try to disentangle the different emotional and rational factors (regret, rejoicing, reward, costs, uncertainty, trade-off between positive and negative aspects of different options). Emotions then appear as much more complex and mixed affective states than usually assumed. Not only might we feel a positive affect in punishing unfair partners, but mixed emotions can, for example, combine transmutation of previous anxiety into relief and elation by comparison with another less exciting option (elating relief). At the level of complexity of these mixed emotions—which we formally represent by comparisons between ‘unexpected utilities’ and expected ones—the main biases that Kahnemann and Tversky have shown can be explained. In spite of the complexity of these mixed emotions, some of these hypotheses might be partially tested by brain imagery. PMID:20026464

Effect of helium to dpa ratio on fatigue behavior of austenitic stainless steel irradiated to 2 dpa

NASA Astrophysics Data System (ADS)

Ioka, I.; Yonekawa, M.; Miwa, Y.; Mimura, H.; Tsuji, H.; Hoshiya, T.

2000-12-01

The effect of helium due to nuclear transmutation reactions during neutron irradiation on low cycle fatigue life of type 304 stainless steel was investigated. The specimens were irradiated in spectrally tailored capsules in the Japan Materials Testing Reactor (JMTR) at a temperature of 823 K to a neutron fluence of approximately 1×1025 n/m2 (E>1 MeV) and helium levels of 0.8, 2.5 and 8.1 appm. The low cycle fatigue tests were performed in total axial strain ranges of 0.8-1.6% at 823 K. A laser extensometer was used for controlling the axial strain of a specimen under cyclic testing. The difference between unirradiated and irradiated specimens is quite clear and appears to be a reduction by a factor of 2-5 in fatigue life. The helium concentration of the specimen is not the main factor to shorten fatigue life in the present experimental condition.

The 1987 Get Away Special Experimenter's Symposium

NASA Technical Reports Server (NTRS)

Barthelme, Neal (Editor); Mosier, Frances L. (Editor)

1988-01-01

The 1987 Get Away Special (GAS) Experimenter's symposium provides a formal opportunity for GAS Experimenter's to share the results of their projects. The focus of this symposium was on payloads that were flown on Shuttle missions, and on GAS payloads that will be flown in the future.

The 1985 Get Away Special Experimenter's Symposium

NASA Technical Reports Server (NTRS)

Thomas, L. R. (Editor); Mosier, F. L. (Editor)

1986-01-01

The 1985 Get Away Special (GAS) Experimenter's Symposium provided a formal opportunity for GAS experimenters to share the results of their projects. The focus is on payloads that have been flown on Shuttle missions, and on GAS payloads that will be flown in the near future.

Comparisons of hydrology, geology, and physical characteristics between Tenderfoot Creek Experimental Forest (east side) Montana, and Coram Experimental Forest (west side) Montana

Treesearch

Phillip E. Farnes; Raymond C. Shearer; Ward W. McCaughey; Katherine J. Hansen

1995-01-01

There are two experimental forests in Montana established by the U.S. Department of Agriculture, Forest Service, Intermountain Research Station (INT). Both experimental forests are administered by INT's Research work Unit, RWU-4151, Silviculture of Subalpine Forest Ecosystems. Tenderfoot Creek Experimental Forest (TCEF) is east of the continental Divide and is...

The flaws and human harms of animal experimentation.

PubMed

Akhtar, Aysha

2015-10-01

Nonhuman animal ("animal") experimentation is typically defended by arguments that it is reliable, that animals provide sufficiently good models of human biology and diseases to yield relevant information, and that, consequently, its use provides major human health benefits. I demonstrate that a growing body of scientific literature critically assessing the validity of animal experimentation generally (and animal modeling specifically) raises important concerns about its reliability and predictive value for human outcomes and for understanding human physiology. The unreliability of animal experimentation across a wide range of areas undermines scientific arguments in favor of the practice. Additionally, I show how animal experimentation often significantly harms humans through misleading safety studies, potential abandonment of effective therapeutics, and direction of resources away from more effective testing methods. The resulting evidence suggests that the collective harms and costs to humans from animal experimentation outweigh potential benefits and that resources would be better invested in developing human-based testing methods.

Experimental demonstration of spinor slow light

NASA Astrophysics Data System (ADS)

Lee, Meng-Jung; Ruseckas, Julius; Lee, Chin-Yuan; Kudriašov, Viačeslav; Chang, Kao-Fang; Cho, Hung-Wen; JuzeliÅ«nas, Gediminas; Yu, Ite A.

2016-03-01

Over the last decade there has been a continuing interest in slow and stored light based on the electromagnetically induced transparency (EIT) effect, because of their potential applications in quantum information manipulation. However, previous experimental works all dealt with the single-component slow light which cannot be employed as a qubit. In this work, we report the first experimental demonstration of two-component or spinor slow light (SSL) using a double tripod (DT) atom-light coupling scheme. The oscillations between the two components, similar to the Rabi oscillation of a two-level system or a qubit, were observed. Single-photon SSL can be considered as two-color qubits. We experimentally demonstrated a possible application of the DT scheme as quantum memory and quantum rotator for the two-color qubits. This work opens up a new direction in the slow light research.

THE COURSE OF EXPERIMENTAL HEMOTHORAX IN RADIATION SICKNESS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, C.C.

1957-05-01

Experimental hemothorax induced by injecting 10 to 12 ml of autogenous blood into the pleural cavity of healthy rabbits was borne well without any marked general reaction. Rabbits irradiated with 600 r were more affected by experimental hemothorax. Instead of absorption, exudation accumulated in the pleural cavity. In rabbits irradiated with 600 r, experimental hemothorax markediy shortened the latent period of radiation sickness and hastened its climax. (C.H.)

Experimental Proteus mirabilis Burn Surface Infection

DTIC Science & Technology

1982-02-01

Reprinted from the Achie of Surgery ECTE February 1982, Volume 117 Copyright 19 2. American Medical Association MAY 2 8 1982 V0A Experimental Proteus ... mirabilis Burn Surface Infection Albert T. McManus, PhD; Charles G. McLeod, Jr, DVM; Arthur D. Mason, Jr, MD * We established a human burn Isolate of... Proteus mirabills as have examined human burn isolates from the genera an experimental pathogen. Infliction of a nonfatal scald injury Enterobacter

78 FR 51678 - Market Tests of Experimental Postal Products

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-21

...] Market Tests of Experimental Postal Products AGENCY: Postal Regulatory Commission. ACTION: Proposed rule... tests of experimental products. The proposed rules address the contents of market test filings, describe... Tests I. Introduction The Commission proposes to establish rules governing market tests of experimental...

9 CFR 103.1 - Preparation of experimental biological products.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Preparation of experimental biological... PRODUCTION, DISTRIBUTION, AND EVALUATION OF BIOLOGICAL PRODUCTS PRIOR TO LICENSING § 103.1 Preparation of experimental biological products. Except as otherwise provided in this section, experimental biological...

9 CFR 103.1 - Preparation of experimental biological products.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Preparation of experimental biological... PRODUCTION, DISTRIBUTION, AND EVALUATION OF BIOLOGICAL PRODUCTS PRIOR TO LICENSING § 103.1 Preparation of experimental biological products. Except as otherwise provided in this section, experimental biological...

9 CFR 103.1 - Preparation of experimental biological products.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Preparation of experimental biological... PRODUCTION, DISTRIBUTION, AND EVALUATION OF BIOLOGICAL PRODUCTS PRIOR TO LICENSING § 103.1 Preparation of experimental biological products. Except as otherwise provided in this section, experimental biological...

Experimental Approach to Teaching Fluids

NASA Astrophysics Data System (ADS)

Stern, Catalina

2015-11-01

For the last 15 years we have promoted experimental work even in the theoretical courses. Fluids appear in the Physics curriculum of the National University of Mexico in two courses: Collective Phenomena in their sophomore year and Continuum Mechanics in their senior year. In both, students are asked for a final project. Surprisingly, at least 85% choose an experimental subject even though this means working extra hours every week. Some of the experiments were shown in this congress two years ago. This time we present some new results and the methodology we use in the classroom. I acknowledge support from the Physics Department, Facultad de Ciencias, UNAM.

The Bigfoot Drive; Experimental Results

NASA Astrophysics Data System (ADS)

Baker, Kevin; Thomas, Cliff; Khan, Shahab; Casey, Daniel; Spears, Brian; Nora, Ryan; Munro, Davis; Eder, David; Milovich, Jose; Berger, Dick; Strozzi, David; Goyon, Clement; Turnbull, David; Ma, Tammy; Izumi, Nobuhiko; Benedetti, Robin; Millot, Marius; Celliers, Peter; Yeamans, Charles; Hatarik, Robert; Landen, Nino; Hurricane, Omar; Callahan, Debbie

2016-10-01

The Bigfoot platform was developed on the National Ignition Facility to investigate low convergence, high adiabat, high rhoR hotspot implosions. This platform was designed to be less susceptible to wall motion, LPI and CBET and to be more robust against capsule hydrodynamic instabilities. To date experimental studies have been carried out at two hohlraum scales, a 5.75 and 5.4 mm diameter hohlraum. We will present experimental results from these tuning campaigns including the shape vs. cone fraction, surrogacy comparisons of self-emission from the capsules vs. radiography of the imploding capsule and doped vs. undoped capsules. Prepared by LLNL under Contract DE-AC52-07NA27344.

Experimental research of radio-frequency ion thruster

NASA Astrophysics Data System (ADS)

Antropov, N. N.; Akhmetzhanov, R. V.; Bogatyy, A. V.; Grishin, R. A.; Kozhevnikov, V. V.; Plokhikh, A. P.; Popov, G. A.; Khartov, S. A.

2016-12-01

The article is devoted to the research of low-power (300 W) radio-frequency ion thruster designed at the Moscow Aviation Institute. The main results of experimental research of the thruster using the testfacility power supplies and the power processing unit of their own design are presented. The dependence of the working fluid ionization cost on its mass flow rate at the constant ion beam current was investigated experimentally. The influence of the shape and material of the discharge chamber on the integral characteristics of the thruster was studied. The recommendations on the optimization of the thruster primary performance were developed based on the results of experimental studies.

Segmented Polynomial Models in Quasi-Experimental Research.

ERIC Educational Resources Information Center

Wasik, John L.

1981-01-01

The use of segmented polynomial models is explained. Examples of design matrices of dummy variables are given for the least squares analyses of time series and discontinuity quasi-experimental research designs. Linear combinations of dummy variable vectors appear to provide tests of effects in the two quasi-experimental designs. (Author/BW)

Neutron-antineutron oscillations: Theoretical status and experimental prospects

DOE PAGES

Phillips, D. G.; Snow, W. M.; Babu, K.; ...

2016-02-01

This paper summarizes the relevant theoretical developments, outlines some ideas to improve experimental searches for free neutron-antineutron oscillations, and suggests avenues for future improvement in the experimental sensitivity.

Devising and Attaining National Health Objectives: A Case Study in Policy Formulation Using Asthma Targets in Healthy People 2000

DTIC Science & Technology

1991-05-06

Phys- (loosely) Quantum Chaos Theory entific Paradigm ics - atomistic move- ments Value Claims transmutes values value isolated into Values incorporat...infant care 3. immunizations 4. sexually transmissible disease services 5. high blood pressure control 6. toxic agent control 7. occupational safety and

Christian Realism’s Response to International Terrorism

DTIC Science & Technology

2002-04-01

defense which cannot be transmuted into instruments of aggression. The frustrations of the average man, who can never realise the power and the...historical existence, tensions have their root in natural, geographic, economic, racial, national and sexual conditions. But since it interprets

Knowledge Value Added (KVA) Methodology as a Tool for Measuring the Utilization of Knowledge Assets Aboard Marine Corps Installations

DTIC Science & Technology

2008-06-01

make better technology investment decisions. C. FOLLOW-ON RESEARCH POTENTIAL Like most assets, knowledge is only valuable if it can be transmuted ...CID Agent Sexual Assault Investigations Training E5 5 Conduct preliminary investigation on referable cases 5811 Basic Military Police Intelligence In

Dynamic Tensile Experimental Techniques for Geomaterials: A Comprehensive Review

NASA Astrophysics Data System (ADS)

Heard, W.; Song, B.; Williams, B.; Martin, B.; Sparks, P.; Nie, X.

2018-01-01

This review article is dedicated to the Dynamic Behavior of Materials Technical Division for celebrating the 75th anniversary of the Society for Experimental Mechanics (SEM). Understanding dynamic behavior of geomaterials is critical for analyzing and solving engineering problems of various applications related to underground explosions, seismic, airblast, and penetration events. Determining the dynamic tensile response of geomaterials has been a great challenge in experiments due to the nature of relatively low tensile strength and high brittleness. Various experimental approaches have been made in the past century, especially in the most recent half century, to understand the dynamic behavior of geomaterials in tension. In this review paper, we summarized the dynamic tensile experimental techniques for geomaterials that have been developed. The major dynamic tensile experimental techniques include dynamic direct tension, dynamic split tension, and spall tension. All three of the experimental techniques are based on Hopkinson or split Hopkinson (also known as Kolsky) bar techniques and principles. Uniqueness and limitations for each experimental technique are also discussed.

An experimental aluminum-fueled power plant

NASA Astrophysics Data System (ADS)

Vlaskin, M. S.; Shkolnikov, E. I.; Bersh, A. V.; Zhuk, A. Z.; Lisicyn, A. V.; Sorokovikov, A. I.; Pankina, Yu. V.

2011-10-01

An experimental co-generation power plant (CGPP-10) using aluminum micron powder (with average particle size up to 70 μm) as primary fuel and water as primary oxidant was developed and tested. Power plant can work in autonomous (unconnected from industrial network) nonstop regime producing hydrogen, electrical energy and heat. One of the key components of experimental plant is aluminum-water high-pressure reactor projected for hydrogen production rate of ∼10 nm3 h-1. Hydrogen from the reactor goes through condenser and dehumidifier and with -25 °C dew-point temperature enters into the air-hydrogen fuel cell 16 kW-battery. From 1 kg of aluminum the experimental plant produces 1 kWh of electrical energy and 5-7 kWh of heat. Power consumer gets about 10 kW of electrical power. Plant electrical and total efficiencies are 12% and 72%, respectively.

Experimental design in chemistry: A tutorial.

PubMed

Leardi, Riccardo

2009-10-12

In this tutorial the main concepts and applications of experimental design in chemistry will be explained. Unfortunately, nowadays experimental design is not as known and applied as it should be, and many papers can be found in which the "optimization" of a procedure is performed one variable at a time. Goal of this paper is to show the real advantages in terms of reduced experimental effort and of increased quality of information that can be obtained if this approach is followed. To do that, three real examples will be shown. Rather than on the mathematical aspects, this paper will focus on the mental attitude required by experimental design. The readers being interested to deepen their knowledge of the mathematical and algorithmical part can find very good books and tutorials in the references [G.E.P. Box, W.G. Hunter, J.S. Hunter, Statistics for Experimenters: An Introduction to Design, Data Analysis, and Model Building, John Wiley & Sons, New York, 1978; R. Brereton, Chemometrics: Data Analysis for the Laboratory and Chemical Plant, John Wiley & Sons, New York, 1978; R. Carlson, J.E. Carlson, Design and Optimization in Organic Synthesis: Second Revised and Enlarged Edition, in: Data Handling in Science and Technology, vol. 24, Elsevier, Amsterdam, 2005; J.A. Cornell, Experiments with Mixtures: Designs, Models and the Analysis of Mixture Data, in: Series in Probability and Statistics, John Wiley & Sons, New York, 1991; R.E. Bruns, I.S. Scarminio, B. de Barros Neto, Statistical Design-Chemometrics, in: Data Handling in Science and Technology, vol. 25, Elsevier, Amsterdam, 2006; D.C. Montgomery, Design and Analysis of Experiments, 7th edition, John Wiley & Sons, Inc., 2009; T. Lundstedt, E. Seifert, L. Abramo, B. Thelin, A. Nyström, J. Pettersen, R. Bergman, Chemolab 42 (1998) 3; Y. Vander Heyden, LC-GC Europe 19 (9) (2006) 469].

Nuclear data activities at the n_TOF facility at CERN

NASA Astrophysics Data System (ADS)

Gunsing, F.; Aberle, O.; Andrzejewski, J.; Audouin, L.; Bécares, V.; Bacak, M.; Balibrea-Correa, J.; Barbagallo, M.; Barros, S.; Bečvář, F.; Beinrucker, C.; Belloni, F.; Berthoumieux, E.; Billowes, J.; Bosnar, D.; Brugger, M.; Caamaño, M.; Calviño, F.; Calviani, M.; Cano-Ott, D.; Cardella, R.; Casanovas, A.; Castelluccio, D. M.; Cerutti, F.; Chen, Y. H.; Chiaveri, E.; Colonna, N.; Cortés-Giraldo, M. A.; Cortés, G.; Cosentino, L.; Damone, L. A.; Deo, K.; Diakaki, M.; Domingo-Pardo, C.; Dressler, R.; Dupont, E.; Durán, I.; Fernández-Domínguez, B.; Ferrari, A.; Ferreira, P.; Finocchiaro, P.; Frost, R. J. W.; Furman, V.; Ganesan, S.; García, A. R.; Gawlik, A.; Gheorghe, I.; Glodariu, T.; Gonçalves, I. F.; González, E.; Goverdovski, A.; Griesmayer, E.; Guerrero, C.; Göbel, K.; Harada, H.; Heftrich, T.; Heinitz, S.; Hernández-Prieto, A.; Heyse, J.; Jenkins, D. G.; Jericha, E.; Käppeler, F.; Kadi, Y.; Katabuchi, T.; Kavrigin, P.; Ketlerov, V.; Khryachkov, V.; Kimura, A.; Kivel, N.; Kokkoris, M.; Krtička, M.; Leal-Cidoncha, E.; Lederer, C.; Leeb, H.; Lerendegui, J.; Licata, M.; Lo Meo, S.; Lonsdale, S. J.; Losito, R.; Macina, D.; Marganiec, J.; Martínez, T.; Masi, A.; Massimi, C.; Mastinu, P.; Mastromarco, M.; Matteucci, F.; Maugeri, E. A.; Mazzone, A.; Mendoza, E.; Mengoni, A.; Milazzo, P. M.; Mingrone, F.; Mirea, M.; Montesano, S.; Musumarra, A.; Nolte, R.; Oprea, A.; Palomo-Pinto, F. R.; Paradela, C.; Patronis, N.; Pavlik, A.; Perkowski, J.; Porras, I.; Praena, J.; Quesada, J. M.; Rajeev, K.; Rauscher, T.; Reifarth, R.; Riego-Perez, A.; Robles, M.; Rout, P.; Radeck, D.; Rubbia, C.; Ryan, J. A.; Sabaté-Gilarte, M.; Saxena, A.; Schillebeeckx, P.; Schmidt, S.; Schumann, D.; Sedyshev, P.; Smith, A. G.; Stamatopoulos, A.; Suryanarayana, S. V.; Tagliente, G.; Tain, J. L.; Tarifeño-Saldivia, A.; Tarrío, D.; Tassan-Got, L.; Tsinganis, A.; Valenta, S.; Vannini, G.; Variale, V.; Vaz, P.; Ventura, A.; Vlachoudis, V.; Vlastou, R.; Wallner, A.; Warren, S.; Weigand, M.; Weiss, C.; Wolf, C.; Woods, P. J.; Wright, T.; Žugec, P.

2016-10-01

Nuclear data in general, and neutron-induced reaction cross sections in particular, are important for a wide variety of research fields. They play a key role in the safety and criticality assessment of nuclear technology, not only for existing power reactors but also for radiation dosimetry, medical applications, the transmutation of nuclear waste, accelerator-driven systems, fuel cycle investigations and future reactor systems as in Generation IV. Applications of nuclear data are also related to research fields as the study of nuclear level densities and stellar nucleosynthesis. Simulations and calculations of nuclear technology applications largely rely on evaluated nuclear data libraries. The evaluations in these libraries are based both on experimental data and theoretical models. Experimental nuclear reaction data are compiled on a worldwide basis by the international network of Nuclear Reaction Data Centres (NRDC) in the EXFOR database. The EXFOR database forms an important link between nuclear data measurements and the evaluated data libraries. CERN's neutron time-of-flight facility n_TOF has produced a considerable amount of experimental data since it has become fully operational with the start of the scientific measurement programme in 2001. While for a long period a single measurement station (EAR1) located at 185 m from the neutron production target was available, the construction of a second beam line at 20 m (EAR2) in 2014 has substantially increased the measurement capabilities of the facility. An outline of the experimental nuclear data activities at CERN's neutron time-of-flight facility n_TOF will be presented.

Assessing Students' Experimentation Processes in Guided Inquiry

ERIC Educational Resources Information Center

Emden, Markus; Sumfleth, Elke

2016-01-01

In recent science education, experimentation features ever more strongly as a method of inquiry in science classes rather than as a means to illustrate phenomena. Ideas and materials to teach inquiry abound. Yet, tools for assessing students' achievement in their processes of experimentation are lacking. The present study assumes a basal,…

30 CFR 785.13 - Experimental practices mining.

Code of Federal Regulations, 2010 CFR

2010-07-01

... purposes, or to allow an alternative postmining land use, and may be undertaken if they are approved by the... accordance with the requirements of subchapter G of this chapter. (b) An application for an experimental... duration of the experimental practice, and any special monitoring which will be conducted; (2) How use of...

Drought Adaptation Mechanisms Should Guide Experimental Design.

PubMed

Gilbert, Matthew E; Medina, Viviana

2016-08-01

The mechanism, or hypothesis, of how a plant might be adapted to drought should strongly influence experimental design. For instance, an experiment testing for water conservation should be distinct from a damage-tolerance evaluation. We define here four new, general mechanisms for plant adaptation to drought such that experiments can be more easily designed based upon the definitions. A series of experimental methods are suggested together with appropriate physiological measurements related to the drought adaptation mechanisms. The suggestion is made that the experimental manipulation should match the rate, length, and severity of soil water deficit (SWD) necessary to test the hypothesized type of drought adaptation mechanism. Copyright © 2016 Elsevier Ltd. All rights reserved.

Immune reactions and allergy in experimental anisakiasis

PubMed Central

Lee, Haneul Nari

2006-01-01

The third-stage larvae (L3) of the parasitic nematode, Anisakis simplex, have been implicated in the induction of hyperimmune allergic reactions in orally infected humans. In this work, we have conducted a review of an investigation into immune reactions occurring in animals experimentally infected with A. simplex L3. The patterns of serum antibody productions in the experimental animals against excretory-secretory products (ESP) of A. simplex L3 contributed to our current knowledge regarding specific humoral immune reactions in humans. In our review, we were able to determine that L3 infection of experimental animals may constitute a good model system for further exploration of immune mechanisms and allergy in anisakiasis of humans. PMID:17170569

Transmutation Fuel Performance Code Thermal Model Verification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gregory K. Miller; Pavel G. Medvedev

2007-09-01

FRAPCON fuel performance code is being modified to be able to model performance of the nuclear fuels of interest to the Global Nuclear Energy Partnership (GNEP). The present report documents the effort for verification of the FRAPCON thermal model. It was found that, with minor modifications, FRAPCON thermal model temperature calculation agrees with that of the commercial software ABAQUS (Version 6.4-4). This report outlines the methodology of the verification, code input, and calculation results.

Research on Hygiene Based on Fieldwork and Experimental Studies.

PubMed

Yajima, Ichiro

2017-01-01

Several experimental studies on hygiene have recently been performed and fieldwork studies are also important and essential tools. However, the implementation of experimental studies is insufficient compared with that of fieldwork studies on hygiene. Here, we show our well-balanced implementation of both fieldwork and experimental studies of toxic-element-mediated diseases including skin cancer and hearing loss. Since the pollution of drinking well water by toxic elements induces various diseases including skin cancer, we performed both fieldwork and experimental studies to determine the levels of toxic elements and the mechanisms behind the development of toxic-element-related diseases and to develop a novel remediation system. Our fieldwork studies in several countries including Bangladesh, Vietnam and Malaysia demonstrated that drinking well water was polluted with high concentrations of several toxic elements including arsenic, barium, iron and manganese. Our experimental studies using the data from our fieldwork studies demonstrated that these toxic elements caused skin cancer and hearing loss. Further experimental studies resulted in the development of a novel remediation system that adsorbs toxic elements from polluted drinking water. A well-balanced implementation of both fieldwork and experimental studies is important for the prediction, prevention and therapy of toxic-element-mediated diseases.

Experimental Neutrino Physics

ScienceCinema

Walter, Chris

2018-01-12

In this talk, I will review how a set of experiments in the last decade has given us our current understanding of neutrino properties.  I will show how experiments in the last year or two have clarified this picture, and will discuss how new experiments about to start will address remaining questions.  I will particularly emphasize the relationship between various experimental techniques.

USACDEC Experimentation Manual

DTIC Science & Technology

1981-10-01

Commander, Instrumentation Command (Prov) who is responsible for the cinematic form of the films. The writing requirements for discrete sections of the...level of simulated realism required. Higher levels of simulated realism will require higher degrees of control to insure the test events occur as...experimentation, the "enemy" created to add realism . Aggressor forces may be represented by live troops In the field or by mechanical targets with or