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排序方式: 共有843条查询结果,搜索用时 15 毫秒
131.
Kenta Inagaki Takatoshi Hijikata Takeshi Tsukada Tadafumi Koyama Keiji Ishikawa Shoichi Ono 《Journal of Nuclear Science and Technology》2014,51(7-8):906-915
A simulation code was developed to evaluate the performance of the cesium adsorption instrument operating in Fukushima Daiichi Nuclear Power Station. Since contaminated water contains seawater whose salinity is not constant, a new model was introduced to the conventional zeolite column simulation code to deal with the variable salinity of the seawater. Another feature of the cesium adsorption instrument is that it consists of several columns arranged in both series and parallel. The spent columns are replaced in a unique manner using a merry-go-round system. The code is designed by taking those factors into account. Consequently, it enables the evaluation of the performance characteristics of the cesium adsorption instrument, such as the time history of the decontamination factor, the cesium adsorption amount in each column, and the axial distribution of the adsorbed cesium in the spent columns. The simulation is conducted for different operation patterns and its results are given to Tokyo Electric Power Company (TEPCO) to support the optimization of the operation schedule. The code is also used to investigate the cause of some events that actually occurred in the operation of the cesium adsorption instrument. 相似文献
132.
Shusuke Kanazawa Musubu Ichikawa Youki Fujita Ryu Koike Toshiki Koyama Yoshio Taniguchi 《Organic Electronics》2008,9(4):425-431
The relationship between thiophene sequences and organic thin-film transistor (OTFT) characteristics was studied to determine their effect on ionization potential, molecular orientation, and air stability. Two types of molecular structures were used: continuous sequence and divided sequence thiophenes. The length of thiophene sequence did not affect FET characteristics but did affect ionic potential and air stability. Furthermore, materials with divided thiophene sequences showed no change in OTFT characteristics when exposed to air. These results suggest that separation of thiophene sequences can improve air stability, which is a problem of thiophene-based materials. 相似文献
133.
Mayuko Iriguchi Hiroki Koda Takamasa Koyama Nobuo Masataka 《Color research and application》2020,45(1):178-182
Women might experience modulation in their perception and cognition of colours and odours during the menstrual cycle, but how women's impressions of and correspondence between colours and odours differ according to the cycle changes remains unknown. Here, we experimentally examined women's performance of several tasks, including evaluation of impressions of colours and odours, matching/nonmatching of colours with odours, and identification of odours, comparing two phases: the beginning of menstruation and ovulation. The results showed that participants had similar impressions of colours and odours and made similar colour choices for odours in both the menstrual and ovulation phases, while “pleasant-unpleasant” impressions of colour and odour might vary according to the menstrual cycle. We found no significant differences in odour identification between the phases. The findings imply that hormonal changes during the menstrual cycle might affect “pleasant-unpleasant” impressions of colour and odour but not other features regarding impressions or crossmodal correspondence. In future studies, examination with a large number of participants is necessary. 相似文献
134.
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136.
K Tanabe T Tokumoto N Ishikawa I Koyama K Takahashi S Fuchinoue T Kawai S Koga T Yagisawa H Toma K Ota H Nakajima 《Canadian Metallurgical Quarterly》1997,64(12):1721-1725
BACKGROUND: Early diagnosis of cytomegalovirus (CMV) infection, which is an important cause of morbidity and mortality in renal transplant recipients, remains of great importance. This prospective study was performed in kidney transplant recipients to determine the diagnostic value of the CMV antigenemia assay in comparison with polymerase chain reaction (PCR), serology, and shell vial assay. METHODS: Seventy-five consecutive renal transplant recipients were enrolled in this study and monitored by both antigenemia assay and serology. The initial 34 of the 75 patients were subjected to PCR and shell vial assay. RESULTS: Antigenemia, PCR, and shell vial assay became positive before the onset of CMV-related symptoms in 31/34 (89%), 13/16 (81%), and 2/16 (13%), respectively. None of the 34 patients who had symptomatic CMV disease showed a significant increase in IgG or IgM before the onset of symptoms. Antigenemia and PCR assays turned positive, 7 and 11 days (median), respectively, before the onset of clinical symptoms. Serology and shell vial assay became positive 21 and 25 days (median), respectively, after the onset of CMV-related clinical symptoms. To examine the clinical value of these assays, "good correlation" was defined based on the correlation between the clinical course and the results of the assays. Good correlation with the antigenemia assay was observed in 33 (96%) out of 34 renal transplant recipients who recovered from their CMV disease after ganciclovir therapy. Only one of 16 (7%) patients showed good correlation by shell vial assay, whereas PCR and serology did not show a good correlation. Consequently, antigenemia was considered the best way to monitor CMV infections after kidney transplantation. CONCLUSIONS: Only the CMV antigenemia assay can be successfully employed after renal transplantation for the early diagnosis and extensive monitoring of active CMV infection. 相似文献
137.
T Nagai Y Hirayama H Ohta R Koyama T Matsunaga T Kuga S Sakamaki Y Niitsu 《Canadian Metallurgical Quarterly》1997,38(6):513-519
This study investigated the association between two demographic and two psychological variables and treatment retention for 65 perinatal substance abusers. Subjects who lived in the community while attending day treatment were 6.125 times more likely to drp out than subjects who lived in a program-operated shelter (p < .0001). An interaction was found for pregnancy status and antisocial personality disorder (p < .0478). Subjects who were both pregnant and antisocial were 4.876 times more likely to remain in treatment than those who were neither pregnant nor antisocial. Degree of "treatment resistance," measured by the MMPI Negative Treatment Indicators (TRT) Scale, did not predict dropout. These findings indicate that supportive housing can play an important role in preventing dropout for perinatal substance abusers. Additionally, pregnancy may present a "window" of opportunity for treating a hard to reach population, drug abusing women with comorbid ASP. 相似文献
138.
Motomichi Koyama Michael Rohwerder Cemal Cem Tasan Asif Bashir Eiji Akiyama Kenichi Takai 《Materials Science & Technology》2017,33(13):1481-1496
ABSTRACTThis paper gives an overview of recent progress in microstructure-specific hydrogen mapping techniques. The challenging nature of mapping hydrogen with high spatial resolution, i.e. at the scale of finest microstructural features, led to the development of various methodologies: thermal desorption spectrometry, silver decoration, the hydrogen microprint technique, secondary ion mass spectroscopy, atom probe tomography, neutron radiography, and the scanning Kelvin probe. These techniques have different characteristics regarding spatial and temporal resolution associated with microstructure-sensitive hydrogen detection. Employing these techniques in a site-specific manner together with other microstructure probing methods enables multi-scale, quantitative, three-dimensional, high spatial, and kinetic resolution hydrogen mapping, depending on the specific multi-probe approaches used. Here, we present a brief overview of the specific characteristics of each method and the progress resulting from their combined application to the field of hydrogen embrittlement.This paper is part of a thematic issue on Hydrogen in Metallic Alloys 相似文献
139.
Arsenic is present at high concentrations in the upper layer of Lake Biwa sediments and shows a depth profile similar to that of Mn. Adsorption experiments of As onto synthetic hydrous Mn oxide (HMO) in the presence of Mn2+ and the speciation of Mn in the sediment cores, suggest that the accumulation of As at the sediment surface results from post-depositional migration of arsenite in the sediment pore water followed by oxidation to arsenate at the sediment surface and adsorption onto Mn2+-rich HMO. 相似文献
140.
Recently, the phase-field method has been extended and utilized across many fields of materials science. Since this method can incorporate, systematically, the effect of the coherency induced by lattice mismatch and the applied stress as well as the external electrical and magnetic fields, it has been applied to many material processes including solidification, solid-state phase transformations and various types of complex microstructure changes. In this paper, we focus on the recent phase-field simulations of real magnetic materials, and the simulation method for magnetic materials is explained comprehensively. Several applications of the phase-field method to clarifying the microstructure changes in magnetic materials, such as Ni2MnGa ferromagnetic shape memory alloy, FePt nanogranular thin film, Co–Sm–Cu rare-earth magnet, Fe–Cr–Co spinodal magnet, and Fe–C steel with external magnetic field, are demonstrated. Furthermore, the general concept of the effective strategy for controlling microstructure in magnetic materials is proposed. 相似文献