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排序方式: 共有1349条查询结果,搜索用时 140 毫秒
991.
Masaki Saito 《Progress in Nuclear Energy》2002,40(3-4):365-374
Environmental harmonization of nuclear energy technology is considered as an absolutely necessary condition in its future successful development for peaceful use. Establishment of Self-Consistent Nuclear Energy System, that simultaneously meets four requirements — energy production, fuel production, burning of radionuclides and safety, strongly relies on the neutron excess generation. Implementation of external non-fission based neutron sources into fission energy system would open the possibility of approaching the Multi-Component Self-Consistent Nuclear Energy System (MC-SCNES) with unlimited fuel resources and zero radioactivity release. This provides strong evidence that nuclear energy could be considered as a base for the future sustainable growth in long perspective. 相似文献
992.
An experimental–computational hybrid system for measurement of thermal conductivity of orthotropic materials is developed. The system consists of two experimental parts and a finite element analysis part. First, the temperature distribution generated by uniform heating is measured with a thermal video system, and the thermal conductivity of Z direction is calculated. Second, the temperature distribution generated by small area heating is measured with the system. In the final step, thermal transfer analyses simulating the experiment support efficient data, and thermal conductivity of in‐plane directions is estimated by comparison between experimental and analytical temperature distributions. The orthotropic equivalent thermal conductivity of honeycomb materials obtained by this system agreed with the theoretical values. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(8): 617–625, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10063 相似文献
993.
The buckling characteristics and layup optimization of long laminated composite cylindrical shells subjected to combined loads of axial compression and torsion are examined on the basis of Flügge’s theory. In the buckling analysis of long laminated composite cylindrical shells, 12 lamination parameters are introduced and used as design variables for layup optimization. Applying a variational approach, the feasible region in the design space of the 12 lamination parameters is numerically obtained. The buckling characteristics are discussed in the design space of the 12 lamination parameters. In the layup optimization, the optimum lamination parameters for maximizing the buckling loads and the laminate configurations for realizing the optimum lamination parameters are determined by mathematical programming methods. It is found that in case of combined loads of axial compression and torsion, the optimum laminate configurations are unsymmetric. 相似文献
994.
In order to calculate stress distribution in unidirectional discontinuous fibres embedded in a metal matrix, a method based on the shear-lag analysis was proposed. Using this method, the influence of fibre length, interfacial bonding strength, distance between fibre ends in the longitudinal direction, and applied strain to composite on both stress distribution and average stress of fibres was estimated for a number of examples. 相似文献
995.
The ozonolysis of 1-phenylazo-2-naphthol was studied using ozone in an oxygen stream. 1-Phenylazo-2-naphthol reacts with ozone to give benzene, chlorobenzene, phenol, o-naphthoquinone, phthalide and phthalic anhydride. The mechanism of the reaction is explained as an electrophilic attack of ozone with the hydrazone tautomer of 1-phenylazo-2-naphthol. 相似文献
996.
K Wakabayashi K Nakamura M Masaki W Yamamoto K Denda Y Nakamura H Yanagawa 《Canadian Metallurgical Quarterly》1995,50(4):839-848
To obtain basic data concerning the availability of medical care for intractable diseases in a large city and its environs, we analyzed the data of Saitama Prefecture. These data were selected from a nationwide survey conducted by the Epidemiology of Intractable Diseases Research Committee of the Ministry of Health and Welfare in Japan. The characteristics of medical institutions visited by patients with 26 intractable diseases were analyzed. The patients were receiving financial aid for treatment. The subjects were 4234 patients in 1984 and 6804 patients in 1988. In addition, we compared the data of 1984 with those of 1988. The results are as follows: 1) In both years, the characteristics of medical institutions which were visited varied in terms of the individual disease. The proportion of patients who visited medical institutions in the same medical service area and in the same prefecture were both very low. The percentage of patients who visited medical institutions in Tokyo was more than 30% of the total, and was more than 50% for the disease with the highest proportion of patients. The dependency on Tokyo for medical institutions was inversely proportional to the distance from Tokyo. Most patients were highly dependent on a large hospital, but the proportion of patients with SMON and ulcerative colitis who visited a large hospital was markedly lower than that for other diseases. 2) A comparison of the data of 1984 with those of 1988 showed that in most of medical service areas, the proportion of patients who visited medical institutions in the same medical service area and in Saitama Prefecture increased, but in Tokyo Prefecture the proportion decreased. We continuously observed a high dependency on a university hospital located about 60km distance from downtown Tokyo, but the dependency slightly decreased in 1988. When a new branch of a university hospital opened, many intractable disease patients then depended on that branch. These results suggest that the self-sufficiency levels of medical services for intractable diseases gradually rose in Saitama Prefecture. The illness behavior of intractable disease patients in Saitama Prefecture did not show any remarkable changes, therefore those results in Saitama Prefecture might indicate a universal characteristic of medical institutions visited by intractable disease patients who live in the envirous of a large city (Tokyo). 相似文献
997.
998.
Hiroshi?NishiharaEmail author Masaki?Murata 《Journal of Inorganic and Organometallic Polymers and Materials》2005,15(1):147-156
We describe here our recent research on -conjutgated organometallic polymers containing ferrocenyl groups. Internuclear electronic interactions through the -conjugated spacer display unique redox and optical properties. The dependence of the redox properties on the number of ferrocene moieties in oligo(1,1-ferrocenylene)s were analyzed by the neighboring-site interaction model. The electronic structure in the mixed-valence states of biferrocene and terferrocene were estimated using the infrared (IR) spectra. Intervalence-transfer (IT) bands in the mixed-valence states of oligo(1,1-ferrocenylene)s were rationalized by taking into account the change in neighboring-site interaction by photo-electron transfer. Near-IR photoconductivity was found for the charge transfer complex of oligo- and poly-(1,1-ferrocenylene)s with tetracycanoethylene (TCNE). Redox and optical properties of azo-bridged ferrocene oligomers and a polymer was also analyazed based on the neighboring-site interaction model. Metallacyclization reaction of para-bis(ferrocenylethynyl)benzene with CpCo(PPh3)2 affforded a ferrocene-containing cyclobutadienecobalt polymer, of which redox property indicates strong intra-unit and weak inter-unit interactions. 相似文献
999.
Ozone decomposition of 2-methylisoborneol (MIB) in adsorption phase on high silica zeolites with preventing bromate formation 总被引:5,自引:0,他引:5
This work elucidates the applicability of our newly developed adsorptive ozonation process for the decomposition of 2-methylisoborneol (MIB), a typical taste and odor chemical, without the formation of possibly carcinogenic bromate ions. First, zeolite adsorbents were screened for their ability to adsorb MIB with a batch-type adsorption experimental apparatus and a flow-type decomposition experimental apparatus included an adsorbent-packed column. The USY zeolite with the highest silica to alumina ratio (SiO(2)/Al(2)O(3) molar ratio=70) showed the best performance as an adsorbent. Using this adsorbent, an ozonation experiment on an MIB solution including bromide ions was performed under various retention times using the flow-type apparatus. As a result, sufficient decomposition of MIB was achieved with preventing bromate formation. 相似文献
1000.
Mitsunori?TakanoEmail author Junichi?Higo Hironori?K.?Nakamura Masaki?Sasai 《Natural computing》2004,3(4):377-393
What granularity is needed to carry out computer simulations of biomolecular reactions/motions? This is one of the central issues of the in silico biomolecular computing. In this paper, we addressed this issue by studying model granularity dependence of the native structure dynamics of protein molecules. We conducted molecular dynamics simulations employing three different protein models: the model with full atomic details and two coarse-grained models in which only Cα atoms interacting with each other through simple potentials are considered. In addition to the observed agreement among the three models in terms of isotropic thermal fluctuation, principal component analysis showed that the coarse-grained models can also reproduce the anisotropy (or directionality) of the fluctuation, particularly of collective modes having relevance to molecular function. This indicates that the dependence of the essential dynamics of a protein molecule on the model granularity is weak, although it was also shown that incorporation of the Lennard–Jones-type potential into the harmonic-potential-based coarse-grained model improves the reproducibility to some degree, and that a plastic nature of structural dynamics observed in the full atomic model transforms into an elastic one in the coarse-grained models. The coarse-grained model can be applied to a molecular motor system, which may lead to a new view of biomolecular computing in the context of biological physics. 相似文献