A3MCNP (Automatic Adjoint Accelerated MCNP) is a revised version of the MCNP Monte Carlo code, which automatically prepares variance reduction parameters for the CADIS (Consistent Adjoint Driven Importance Sampling) methodology. Using a deterministic ‘importance’ (or adjoint) function, CADIS performs source and transport biasing within the weight-window technique. The current version of A3MCNP uses the three-dimensional (3-D) Sn transport TORT code to determine a 3-D importance function distribution. Based on simulation of several real-life problems, it is demonstrated that A3MCNP provides precise calculation results with a remarkably short computation time by using the proper and objective variance reduction parameters. However, since the first version of A3MCNP provided only a point source configuration option for large-scale shielding problems, such as spent-fuel transport casks, a large amount of memory may be necessary to store enough points to properly represent the source. Hence, we have developed an improved version of A3MCNP (referred to as A3MCNPV) which has a volumetric source configuration option. This paper describes the successful use of A3MCNPV for a concrete cask neutron and gamma-ray shielding problem, and a PWR dosimetry problem.
In order to study the temperature dependence of the Bauschinger effect and to obtain information about the origin of the effect, compressive flow behavior of polycrystalline aluminium prestrained by tension up to a fixed value of σ⁄E (σ: stress, E: the Young's modulus) was investigated at temperatures between 20 and 300°C. Several kinds of parameters to evaluate the Bauschinger effect, which are respectively in terms of stress, strain and energy, were measured at various amounts of reversed strains. These parameters, which are considered to be closely related to dislocation structures due to pre-straining and reversed straining, showed different temperature dependences. This fact indicates that the greatest care must be taken in comparing the results by different authors.From the parameters obtained at small reversed strains it is concluded that the degree of the effect decreases with increasing temperature. Such temperature dependence of the effect is well explained from the change in dislocation structures with deformation temperature. The parameters determined at relatively large reversed strains seem to be greatly influenced by the change in dislocation structures during the reversed straining.
Structural changes in copper single crystals during high temperature creep deformation were investigated by means of the Berg-Barrett method. Creep tests were performed in argon atmosphere at 0.75 Tm=745°C and 0.85 Tm=880°C (Tm : the melting temperature in degrees Kelvin). In order to obtain the three-dimensional information on the substructures, two kinds of observation surfaces were prepared by cutting the specimens crept to various strains electrochemically : one parallel to the primary slip plane (111) and the other parallel to the (\bar101) plane on which deformation bands due to the primary slip are formed. A third observation surface is the original specimen surface, i.e. the (1\bar21) plane which is normal to the lattice rotation axis in the deformation band.In the transient creep stage pillar-like subgrains elongating in the direction of [1\bar21] were observed. They were surrounded by sub-boundaries parallel to the (111) and (\bar101) plane which were twist and tilt boundaries, respectively. Spacings between the sub-boundaries were about 30∼50 μ at 745°C and 50∼100 μ at 880°C; the spacings remained almost the same throughout the steady-state creep stage. In the examination of the (111) plane, apparent lattice twisting of the (111) plane about the [1\bar21]-axis was found with a period of about 10 μ. The increase in the twist angle was the most remarkable structural change during creep deformation.
6-Isobutyrylbenzocycloalken-5-ones (4) exist in the enol form in solution. The seven- and eight-membered enolic 1,3-diketones (4c) and (4d) underwent photoketonization and subsequent type II reaction to generate biradicals which were trapped by oxygen to yield the furanones (5) and (6), and the peroxide (7)[only formed from (4c)] in various solvents in the presence of oxygen, whereas the six-membered enolic 1,3-diketone (4a) underwent oxidative dehydrogenation to yield the naphthol (10). Photoreaction of the six-membered enolic 1,3-diketone (4b) in the presence of oxygen gave the naphthalenone (11) and the epoxide (12).
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Approaches to the employment of people with disabilities generally fall into two types: the 'equality of opportunity approach', based on anti-discrimination laws, and the 'employment quota approach', which is based on employment quota systems. The US has adopted an equality of opportunity standard for the employment of people with disabilities, and the defining characteristics of its approach lie in its mandate to provide reasonable accommodations by employers for people with disabilities. In contrast, Japan has adopted an employment quota system. This system is premised on a distinction between people with disabilities and people without disabilities, and mandates the employment of people with disabilities according to established numerical standards. Japan and the US thus have adopted extreme ends of the spectrum of employment protections for the disabled. While the equality of opportunity approach practiced in the US guarantees remedies against discrimination and allows for flexible responses to specific circumstances, it creates problems for employers attempting to predict what constitutes discrimination. The Japanese system, which has adopted an employment quota approach, is able to secure positive effects within certain parameters, but is characterized by an inadequate perspective on the equal treatment of people with disabilities and on prohibitions against their discrimination, and lacks a sense of association between disabilities and job performance.
