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The fifth version of Japanese Evaluated Nuclear Data Library, JENDL-5, was developed. JENDL-5 aimed to meet a variety of needs not only from nuclear reactors but also from other applications such as accelerators. Most of the JENDL special purpose files published so far were integrated into JENDL-5 with revisions. JENDL-5 consists of 11 sublibraries: (1) Neutron, (2) Thermal scattering law, (3) Fission product yield, (4) Decay data, (5) Proton, (6) Deuteron, (7) Alpha-particle, (8) Photonuclear, (9) Photo-atomic, (10) Electro-atomic, and (11) Atomic relaxation. The neutron reaction data for a large number of nuclei in JENDL-4.0 were updated ranging from light to heavy ones, including major and minor actinides which affect nuclear reactor calculations. In addition, the number of nuclei of neutron reaction data stored in JENDL-5 was largely increased; the neutron data covered not only all of naturally existing nuclei but also their neighbor ones with half-lives longer than 1 day. JENDL-5 included the originally evaluated data of thermal scattering law and fission product yield for the first time. Light charged-particle and photon-induced reaction data were also included for the first time as the JENDL general purpose file.

Measurements of 243Am and 235U fission reaction rates are conducted with the use of two single fission chambers in the solid-moderated and solid-reflected core at the Kyoto University Critical Asse...

Uncertainty quantification of lead (Pb) and bismuth (Bi) sample reactivity worth is numerically determined using the SCALE6.2 code system and experimental results obtained from the solid-moderated ...

The accelerator-driven system (ADS) had been proposed for producing energy and transmuting minor actinide and long-lived fission products. ADS has attracted worldwide attention in recent years beca...

The count-loss effect often produces serious problems for the neutron correlation methods that employ a single neutron counting system, since this effect deteriorates the information extracted from subcritical reactor systems. On the other hand, it has been considered that the neutron correlation methods that employ two sets of neutron counting systems, e.g., the covariance-to-mean and the cross-correlation methods, are inherently robust against the count-loss effect in determining the prompt neutron decay constant. The present study investigated this virtue of the latter methods on the basis of a rigorous theoretical approach for treating the count-loss process. The investigation clarified that they indeed show the robustness against the count-loss effect except for extremely high counting rate cases. In the present study, new and alternative formulae of these methods with an explicit correction of the count-loss effect were hence proposed for such extreme cases.

To validate lead (Pb) nuclear cross sections, a series of integral experiments to measure lead void reactivity worths was conducted in a high-enriched uranium (HEU)/Pb system and a low-enriched ura...

Research with fast reactors has drawn interest in the investigation of their characteristics, their applications involving fast neutrons, and such. In this study, to examine the feasibility of the fast core design with the use of three low-enriched uranium (LEU) fuels (Al-alloy LEU, Metal-LEU and U10Mo) at the Kyoto University Critical Assembly (KUCA), numerical simulations with the MCNP6.1 code are conducted with 3-D assembly model of one fuel assembly in the infinite lattice of fuel assemblies to determine 1) performance of the candidate LEU fuels; 2) effect of reflectors and 3) combination of fuel and other plates in the fuel region. Based on the results, the reactor characteristics are analyzed through the full 3-D core model. Consequently, the fast reactor meeting the safety regulations at KUCA is found feasible with the use of the Metal-LEU fuel together with graphite and lead plates, while the other LEU fuels present difficulty in achieving criticality in the designed fast reactor. Finally, the design analyses could offer basic data for onward plans and operation of the KUCA core for fast reactor experiments.

An inconsistency between the reactivity worth of short-sized samples measured by the critical-water-level (CWL) method and that conventionally analyzed for validating nuclear data and nuclear calcu...

In the 1980s, a series of integral experiments was conducted in FCA-IX assemblies with systematically changed neutron spectra covering from the intermediate to fast ones. The experiments provide systematic data of central fission rates for TRU nuclides containing minor actinides, 237Np, 238Pu, 239Pu, 242Pu, 241Am, 243Am, and 244Cm. Regarding the fission rate ratios relative to 239Pu, benchmark models had been recently developed for validation of nuclear data for the TRU's fission cross sections. In this paper, the latest major nuclear data libraries, JENDL-4.0, ENDF/B-VII.1, and JEFF-3.2, are compared on the benchmark models. For the libraries, the analyses by a Monte Carlo calculation code show obvious overestimations particularly for the fission rate ratios of 244Cm to 239Pu. Additionally, a large discrepancy about by 20% between the libraries is revealed for the fission rate ratio of 238Pu to 239Pu measured in the intermediate neutron spectrum. The causes of discrepancies are furthermore clar...

Sample reactivity worth experiments are carried out by substituting aluminum (Al) plates for bismuth (Bi) ones at the Kyoto University Critical Assembly. At the beginning, uncertainty quantification of bismuth isotope is conducted by deterministic calculations with nuclear data library JENDL-4.0, with the use of experimental results of sample reactivity worth. Then, with the combined use of current (Bi) and previous (Pb) experimental results that demonstrate the comparative difference in the sensitivity and uncertainty of Bi and Pb isotopes, experimental results of cross-section uncertainties of Bi isotope are available for examination of neutron characteristics of Pb–Bi coolant material in the accelerator-driven system. From the experimental analyses, further uncertainty analyses by neutron transport calculations are needed for several reactions of Bi isotope, especially with the use of the covariance data of capture, elastic scattering and inelastic scattering reactions in another nuclear data l...

New benchmark models with respect to criticality data are established on the basis of seven uranium-fueled assemblies constructed in the ninth experimental series at the fast critical assembly (FCA...

It was pointed out in the previous paper that the neutron decay constant determined by the pulsed neutron source method that employs the neutron detection system operated in the pulse mode is expected to be biased owing to the count-loss effect even when the intensity of pulsed neutron source is not high. To avoid this difficulty, by paying attention to the current mode that is inherently free from the count-loss process, the pulsed neutron source method with neutron detection system operated in the current mode was proposed. Using this method, not only the neutron decay constant but also the absolute value of subcriticality are obtained when a proper time constant of neutron detection system is selected.

We have developed a void reactivity evaluation method by using modified conversion ratio measurements in a light water reactor (LWR) critical lattice. Assembly-wise void reactivity is evaluated fro...

In the present study, an airship for the fixed point observation of nara withering in village forests was designed and trial manufactured. The airship consists of a helium gas filling envelope of 4.5m in total length, propeller-driven motors, a polymer electrolyte fuel cell (PEFC) in order to achieve longer flight, Ni-H batteries, a CCD camera observation system, and propeller control systems. Automatic charging device was designed to charge the Ni-H battery from the PEFC in the sky automatically. It controlls the power system by using a micro computer in a mannar where the electromagnetic valve supplying hydrogen is open to recover the output voltage of the PEFC when the voltage of Ni-H battery decreased to a certain level, resulting in energy charging to the Ni-H battery and keeping the rotation of the moter. The opened electromagnetic valve is closed when the Ni-H battery full charged. Furthermore, after a certain hours operation when the output voltahge of the PEFC drops due to accumulation of impurities in hydrogen gas, the outlet valve will be opened to exhaust hydrogen containing accumulated impurities. It has been verified that as soon as the Ni-H battery voltage doropped to less than 3.8 [, the hydrogen inlet valve opened then the output of the power source increased suddnly to around 7 [.

It is well known that the count-loss effect produces serious problems for the neutron correlation methods that employ a single neutron counting system, e.g. the variance-to-mean and the auto-correlation methods, since it deteriorates the information extracted from the subcritical reactor system. New formulae of the variance-to-mean and auto-correlation methods were hence obtained on the basis of a rigorous theoretical approach for treating the count-loss process. It is expected that the present formulae work better than conventional ones for determination of the neutron decay constant.

The count-loss effect in determination of neutron decay constant by pulsed neutron source method was investigated. It was found that overestimation of neutron decay constant due to count-loss effect is seen while underestimation appears superiorly as the intensity of pulsed neutron source is getting higher. It was further demonstrated that the well-known count-loss correction procedures are not effective for overestimation although they suppress underestimation. Therefore, the pulsed neutron source method should be modified so as to have robustness against the count-loss effect.

We have developed inexpensive and easy-handling measurement methods on intra-pellet neutron flux. A foil activation method with metallic foils, which were fabricated by punching out technique and etching technique to reduce fabrication error and positioning error, was used for the intra-pellet neutron flux distribution measurement. The developed method was applied to measure intra-pellet neutron flux distributions in a reduced–moderation light water reactor (LWR) lattices, and uncertainty of the distributions was estimated to be 1% to 2%. Measured values were analyzed with a continuous energy Monte Carlo code. Comparison of measurements and analyses revealed that the developed method is useful for the validation of an advanced fuel design method considering neutron behavior in fuel pellets.

At the fast critical assembly (FCA) of JAEA, central fission rate ratios for TRU such as 237 Np, 238 Pu, 239 Pu, 242 Pu, 241 Am, 243 Am, and 244 Cm were measured in the seven uraniumfueled assemblies (FCA-IX assemblies) with systematically changed neutron spectra. The FCA-IX assemblies were constructed with simplicity both in geometry and composition. By virtue of these FCA-IX assemblies where the simple combinations of uranium fuel and diluent (graphite and stainless steel) in their core regions were systematically varied, the neutron spectra of them cover from the intermediate to fast one. Taking their advantages, benchmark models with respect to the central fission rate ratios had been recently developed for the evaluation of the TRU’s fission cross sections. As an application of these benchmark models, the Japanese Evaluated Nuclear Data Library JENDL-4.0 was utilized by a Monte Carlo calculation code. Several results show large discrepancies between the calculation and experimental values. The benchmark models would be well suited for the evaluation and modification of the nuclear data for the TRU’s fission cross sections.

A reflector reactivity worth was measured by replacing stainless steel with zirconium at the FCA. The experimental result of the positive reflector reactivity worth demonstrates the effectiveness of the zirconium reflector compared with the SS reflector in the fast reactor core. This paper also focuses on the validation of standard calculation methods used for fast reactors with JENDL-4.0. As a result, it is confirmed that the standard calculation methods for the reflector reactivity worth show agreement within the experimental error.

The present paper describes the evaluation of the control rod worth data obtained in the Monju restart core. The best-estimate value and its uncertainty are evaluated in detail. As in the criticali...

The benchmark specification for the sodium-void reactivity experiments is given. The detailed benchmark calcu- lations for the new integral data were performed by using a continuous-energy Monte Carlo code (MVP) with use of the evaluated nuclear data libraries JENDL-3.2, -3.3, -4.0, ENDF/B-VII.0 and JEFF-3.1. The MVP calculations were performed with 2,000,000,000 particles. The statistical uncertainties of the MVP calculations were within several percents of the measured sodium-void reactivities. The ratios of calculated to experimental (C/E) values of sodi- um-void reactivities with respect to JENDL-3.3, ENDF/B-VII.0 and JEFF-3.1 are less than those with respect to JENDL-3.2 and -4.0. The analysis results are similar to those of sodium-void reactivities previously obtained at the BFS facility which is another fast critical assembly in Russia. The benchmark calculations demonstrate the improve- ment of the reliability of the integral data such as the new integral data obtained at the FCA and the previously obtained data in the BFS and the usefulness of the new integral data for the validation of the re-evaluated cross sec- tion of 235 U. In addition, the benchmark tests with various correction factors by a deterministic calculation system are summarized for the help to validate the re-evaluated capture cross section of 235 U.

Rh(I) catalyzes the reductive coupling reaction of a wide variety of aldehydes with conjugated dienes in the presence of a stoichiometric amount of triethylborane to provide homoallyl alcohols in a single operation.

Two extended bias factor methods, the LC and PE methods, were applied to the prediction accuracy evaluation of neutronic characteristics of a breeding light water reactor, using data of FCA-XXII-1 critical experiments, in order to investigate the features and effectiveness of these methods on the basis of an actual core design and existing experimental results. The present study confirms the following features of these methods. Both the LC and PE methods can improve the prediction accuracy the most when all the experimental results are used. The prediction accuracy improvement is achieved mainly by reducing uncertainty due to errors in cross sections. This is done by realizing a profile of sensitivity coefficients closer to that of the target core and suppressing the influence of errors in experiments and experimental analysis methods. The PE method always improves the prediction accuracy with the use of any combination of experimental results. It is always superior to the LC method in the improvement of ...

The Doppler reactivity effect of 238 U was measured in simulated MOX fuel using the FCA facility for the purpose of obtaining data on the 238 U Doppler reactivity effect in light-water-moderated MOX fuel and evaluating the prediction accuracy of the current analysis code systems and nuclear data library. Experimental data on the Doppler reactivity effect from room temperature up to 800°C were obtained for a uranium fueled core and mockup cores for MOX-fueled LWR using cylindrical natural-uranium samples. With the use of various samples with various neutron spectra, 238 U Doppler reactivity effects at energies generally in the low range below 1 keV were evaluated. Analyses were performed using the current standard analysis code systems for fast and thermal reactors, with the JENDL-3.3 data library. Both analyses yielded calculated/experimental value (C/E) ratios of 0.96 to 1.06 for the MOX cores, a good agreement within the experimental error, and those in the uranium core were similar.

We consider clusterized nucleonic matter with crystal structure which is described by Bloch function. By using Bloch function, we can describe two extreme states, isolated clusterized matter and uniform matter, in low and high density, respectively, and also intermediate states continuously. We treat not only α-cluster matter but also 10He-and 16O-cluster matter by introducing p-wave Bloch function orthogonal to s-wave Bloch function. P-shell cluster-like density fluctuation arises below a certain critical density as well as s-shell cluster-like one.

The combination of Pd catalyst and Xantphos ligand in the presence of Et(3)B nicely promotes the allylation of aldehydes with conjugated dienes to provide dienyl homoallyl alcohols in excellent yields. The reaction occurs selectively at the C-C double bond bearing higher electron density.

We study abelian dominance and monopole condensation for the quark confinement physics using the lattice QCD simulations in the MA gauge. These phenomena are closely related to the dual superconductor picture of the QCD vacuum, and enable us to construct the dual Ginzburg-Landau (DGL) theory as an useful effective theory of nonperturbative QCD. We then apply the DGL theory to the studies of the low-lying hadron structure and the scalar glueball properties., Talk given at 15th International Conference on Particle and Nuclei (PANIC 99), Uppsala, Sweden, 10-16 Jun 1999, 4 pages

In Quark Nuclear Physics (QNP), where hadrons and nuclei are described in terms of quarks and gluons, confinement and chiral symmetry breaking are the most fundamental phenomena. The dual Ginzburg-Landau (DGL) theory, which contains monopole fields as the most essential degrees of freedom and their condensation in the vacuum, is able to describe both phenomena. We discuss also the recovery of the chiral symmetry and the deconfinement phase transition at finite temperature in the DGL theory. As for the connection to QCD, we study the instanton configurations in the abelian gauge a la 't Hooft. We find a close connection between instantons and QCD monopoles. We demonstrate also the signature of confinement as the appearance of long monopole trajectories in the MA gauge for the case of dense instanton configurations.

The palladium-catalyzed three-component coupling reaction of allylic alcohols, terminal alkynes, and organoboranes preferentially gives (E)-substituted alkylpentadienes, involving geminal allylation and alkylation at the acetylenic terminal carbon.

Tandem reaction: The Pd-catalyzed three-component coupling reaction of an allylic alcohol, terminal alkyne, and organoborane to give (E)-1-substituted 2-alkyl-1,4-pentadienes, involving geminal allylation and alkylation at the acetylenic terminal carbon, is described. Bis-diene undergoes a similar multicomponent coupling reaction with acetylene and organoborane, involving cyclization of bis-π-allylpalladium, to form trans-allyl pentadienyl cyclic and heterocyclic compounds with excellent regio- and stereoselectivities (see scheme).