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81.
Kiyonami Takano Ken Nozaki Yoshiyasu Saito Akira Negishi Ken Kato Yoshio Yamaguchi 《Journal of power sources》2000,90(2):214-223
The electrical dynamic characteristics of a lithium-ion battery have been simulated by an equivalent circuit, which is derived from the measured impedance. The transient voltage response to the various kinds of applied current waves such as single pulse, single rectangular, triangle, and sawtooth waves is experimentally examined and calculated by using the numerical Laplace transform with the equivalent circuit. The experimental and calculated results are compared and discussed, focusing on the range of current where the linear relationship is valid. Changing the time range, the state of charge (SOC) and the battery temperature as parameters, their influence on the linear range of the applied current has been investigated. 相似文献
82.
83.
The FEMAXI-IV code is an extension of the earlier version FEMAXI-III. The primary improvement in the new version is the provision for treating the fuel rod behavior during an operational transient. For this purpose, the time-dependent models are used for heat conduction, fission gas release, and mixing of the released gas with the plenum gas.In FEMAXI-IV, the fission gas release model was thoroughly revised from the previous version. It is based on the fission gas release model presented by White and Tucker. The model takes into account the following mechanisms:
- • - diffusion of gas atoms to the grain boundary;
- • - sweeping of gas atoms by grain growth;
- • - precipitation of gas atoms into intragranular gas bubbles;
- • - resolution of gas atoms from intragranular and grain boundary gas bubbles;
- • - fission gas release due to bubble interconnection.
84.
When a molten UO2 jet impinges on a steel structure in a reactor vessel during a severe accident, the erosion rate of the steel by the molten UO2 jet is expected to be limited considerably by a UO2 crust layer forming on a molten steel substrate at the jet/steel plate interface. A series of simulation experiments was performed to study the melting behavior of solid plates by high temperature liquid jets and the effects of crust forming at jet/structure interface. In the first series of experiments, salt (NaCl) was selected as the jet material and tin (Sn) as the solid structure. The experiments were conducted with varying the jet diameter (10 30 mm) and jet temperature (900 1100°C). The jets were accelerated to a range of 3 5 m/s at the nozzle outlet by gravitational force and impinged perpendicularly to the solid plate underneath. Furthermore, to check the effects of the thermo-physical properties on the erosion behaviors, preliminary experiments were performed by using a molten Al2O3 jet ( 2200°C) impinging on stainless steel plate at room temperature. The erosion rates obtained in the present experiments were far less than the values predicted by an analytical solution that neglects the existence of a crust layer and its thermal effects. With the inclusion of the crust behavior in the model, the experimental results were predicted fairly well. From the present experiments, a Nusselt number of the turbulent heat transfer, which takes into account simultaneous melting and freezing in the impingement region of a molten jet, is correlated by a Reynolds number and a Prandtl number as follows: Num = 0.0033 Re---Pr.In conclusion, the existence of a crust layer plays an important role in the erosion process of a solid plate by the molten fuel jet with high melting point as in a reactor situation. 相似文献
85.
Saito M Kozutsumi D Kawasaki M Kanbashi M Nakamura R Sato Y Endo M 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2008,49(3):228-238
A simple, sensitive and selective method with gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/tandem mass spectrometry (LC/MS/MS) has been developed to detect 342 pesticides and veterinary drugs contaminating bovine milk at the maximum residue limits (MRLs) defined in the "positive list system". Sample preparation was performed by extracting the analytes with acetonitrile, followed by salting-out with sodium chloride. For some pesticides, the extract was further cleaned up by n-hexane partitioning and PSA cartridge column chromatography. GC/MS-EI or -NCI was used to determine pesticide residues, while LC/MS/MS-ESI was applicable to the determination of pesticide and veterinary drug residues. The variation of the recoveries of these drugs at MRL was relatively wide; however the relative standard deviations of the recovery of each drug were within 28%, suggesting that the present method is good enough for use as a screening test for contaminants at the MRLs. These results show that this method is useful for multiresidue analysis of numerous pesticides and veterinary drugs in bovine milk. 相似文献
86.
Kimura N Nagayama T Takano I Kobayashi M Tamura Y Tateishi Y Kitayama K Saito K 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2003,44(1):63-68
A simplified simultaneous analytical method of imazalil (IZ) and its major metabolite, alpha-(2,4-dichlorophenyl)-1H-imidazole-1-ethanol (IZM), in citrus fruits was developed, and commodities samples were investigated. A homogenate of citrus fruits was extracted with ethyl acetate under basic conditions. The crude extract was partitioned between 0.025 mol/L of sulfuric acid and ethyl acetate. The analytes were extracted from the aqueous fraction under basic conditions with ethyl acetate. The extract solution was purified with an ENVI-Carb cartridge, and then analyzed by GC-FTD and GC/MS. Recoveries of IZ and IZM added to grapefruit at the level of 0.05 microgram/g were 90.0 and 108.7%, and those in the case of lemon were 100.4 and 93.0%, respectively. The detection limits were 0.01 microgram/g in samples. By this method, IZ and IZM were analyzed in 46 citrus fruits on the market and were detected simultaneously in some samples. 相似文献
87.
Perfluorinated surfactants in surface, subsurface water and microlayer from Dalian Coastal waters in China 总被引:5,自引:0,他引:5
Two predominant perfluorinated compounds (PFCs), Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), in surface water (SW, 0-20 cm), subsurface water (SSW, > 30 cm depth), and sea surface microlayer (SML, 50 microm thickness) were measured from Dalian Coastal waters in China. The SML samples were collected using glass-plate dipping method. Analysis of the PFCs was conducted through solid-phase extraction, followed by LC/MS-SIM. The PFC's concentrations in SW samples were consistent with previously reported data in this region. Significantly higher concentrations of PFCs were found in SML samples than corresponding SSW samples. The enrichment factors (EF = C(SML)/C(SSW)) for PFOS were as high as 24-109 atthree near-shore sites. The concentration in SW was also generally higher than corresponding SSW samples, giving C(SW)/C(SSW) mean ratios of 1.5 and 1.4 for PFOS and PFOA, respectively. This apparent enrichment of PFCs in surface water, especially in the microlayer, has implications for designing measurement techniques, understanding their distributions, and sea spray-mediated transport in the environment. 相似文献
88.
K Sakaguchi JE Herrera S Saito T Miki M Bustin A Vassilev CW Anderson E Appella 《Canadian Metallurgical Quarterly》1998,12(18):2831-2841
89.
M Furuta K Hayakawa S Katano Y Saito Y Nakayama T Takahashi R Imai T Ebara N Mitsuhashi H Niibe 《Canadian Metallurgical Quarterly》1996,26(2):95-98
Vaccination with peptides that induce a specific immune response is a potential prophylactic or therapeutic strategy against viral infections and tumors. Because of the extensive polymorphism of the HLA loci, synthetic peptide vaccines must consist of a cocktail of peptides that bind specifically to different HLA molecules. Such cocktails should be optimized for the target population as each population has its specific HLA gene frequencies. To achieve maximum population coverage with a minimum number of peptides, information is needed on the ranking of the most frequent HLA phenotypes. We introduce the minimal phenotype panel, which is the smallest combination of HLA antigens selected so that the proportion of individuals in a population that express at least one of the antigens in the panel exceeds a desired minimum value. We developed a method for assembling minimal phenotype panels based on known HLA class I gene frequencies. We give an example based on a set of 2446 well-defined HLA-typed, random, healthy, unrelated, Dutch Caucasoid individuals. In addition, we discuss the possibility of assembling minimal phenotype panels based on two-locus haplotypes, which enables the assembly of phenotype panels from the antigens of both loci. 相似文献
90.
T Imaizumi K Saito T Kobayashi Y Sakamoto T Komeichi 《Canadian Metallurgical Quarterly》1996,24(7):639-642
A 32-year-old man who presented with subarachnoid hemorrhage was found to have a saccular aneurysm arising from the proximal end of the fenestration formed at the distal third of basilar artery. The aneurysm dome was directed anteriorly and measured 3mm in diameter. It was successfully clipped via subtemporal transtentorial approach and the patient returned to his previous job. Basilar artery fenestration is angiographically found in 0.23-0.6%. The fenestration is most frequently located in the proximal basilar trunk close to the vertebro-basilar junction. In this report a rare case with an aneurysm associated with fenestration in the distal part of the basilar artery will be presented. 相似文献