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91.
Phosphorus flame retardants in indoor dust and their relation to asthma and allergies of inhabitants
A. Araki I. Saito A. Kanazawa K. Morimoto K. Nakayama E. Shibata M. Tanaka T. Takigawa T. Yoshimura H. Chikara Y. Saijo R. Kishi 《Indoor air》2014,24(1):3-15
Organophosphate esters are used as additives in flame retardants and plasticizers, and they are ubiquitous in the indoor environment. Phosphorus flame retardants (PFRs) are present in residential dust, but few epidemiological studies have assessed their impact on human health. We measured the levels of 11 PFRs in indoor floor dust and multi‐surface dust in 182 single‐family dwellings in Japan. We evaluated their correlations with asthma and allergies of the inhabitants. Tris(2‐butoxyethyl) phosphate was detected in all samples (median value: 580 μg/g in floor dust, 111 μg/g in multi‐surface dust). Tris(2‐chloro‐iso‐propyl) phosphate (TCIPP) was detected at 8.69 μg/g in floor dust and 25.8 μg/g in multi‐surface dust. After adjustment for potential confounders, significant associations were found between the prevalence of atopic dermatitis and the presence of TCIPP and tris(1,3‐dichloro‐2‐propyl) phosphate in floor dust [per log10‐unit, odds ratio (OR): 2.43 and 1.84, respectively]. Tributyl phosphate was significantly associated with the prevalence of asthma (OR: 2.85 in floor dust, 5.34 in multi‐surface dust) and allergic rhinitis (OR: 2.55 in multi‐surface dust). PFR levels in Japan were high compared with values reported previously for Europe, Asia‐Pacific, and the USA. Higher levels of PFRs in house dust were related to the inhabitants' health status. 相似文献
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94.
Hirooki Tokoi Kinya Kobayashi Hideaki Nagashima Shuichi Ishizawa Yuji Enomoto 《Electrical Engineering in Japan》2016,194(1):37-47
This paper describes a method of predicting the life span of the dies used in motor manufacture from soft magnetic composites (SMCs). In the present study, a clawtooth motor was used. The method involves performing a stress analysis of a die followed by fatigue testing of test pieces. In the analysis, the SMC was assumed to be in powder form and its yield function was derived by a simple method. In addition to the analysis, we describe a simpler and more effective method in which the properties of the SMC are treated as boundary conditions. In the fatigue tests, we used test pieces that simulated the shape and construction material of the die. To predict the life span of the die, we evaluate the SN diagram, which represents the relationship between the maximum stress and fatigue life with respect to the stress generated in the die. The life expectancy of a new die, which is about 100 cycles of use, is found to agree substantially with its actual life. Furthermore, we explain how to extend the life span of a die to the targeted life span, namely, more than 200,000 cycles of use, by changing its shape to reduce stress. 相似文献
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96.
Hong-Baek Cho Bae Uk Lee Chung-Han Ryu Tadachika Nakayama Yeung-Ho Park 《Korean Journal of Chemical Engineering》2013,30(2):306-313
The effect of sodium promotion on the selective hydrogenation of 4-isobutylacetophenone, 4-IBAP, was investigated over a Pd/C catalyst. A precipitation and deposition method was used to prepare the catalyst, and sodium was promoted on the Pd/C catalyst via post-impregnation while varying the sodium content. The sodium-promoted Pd/C catalyst resulted in a significantly improved yield greater than 96% of the desired product, 1-(4-isobutylphenyl) ethanol (4-IBPE), compared with the non-patented literature results under a mild hydrogenation condition. A detailed hydrogenation network over the Pd/C catalyst was suggested. The reaction mechanism for the yield and selectivity enhancement of 4-IBPE induced-by the promoted Pd/C was elucidated in relation to the geometric and electronic effects of reactant molecules in the microporous support depending on the reaction steps. 相似文献
97.
Chikara Tsutsumi Ryouji Watanabe Ayaka Tokumaru Nao Kuwaoka Yuushou Nakayama Takeshi Shiono 《应用聚合物科学杂志》2016,133(39)
Synthetic l ‐lactide random copolymers can be employed as controlled release materials when prepared using supercritical carbon dioxide (scCO2), since they are biodegradable via hydrolysis. To determine the effects of thermal properties on polymer performance following scCO2 processing, three types of poly(l ‐lactide) having different properties were assessed. The Tm of one poly(l ‐lactide) sample (H‐100) was found to be approximately 170 °C over the processing pressure range from 8 to 18 MPa, while a second sample (H‐440) also showed a constant value of approximately 152 °C. In contrast, the poly(l ‐lactide) REVODE exhibited a Tm of 146 °C prior to processing but a higher value of 147 °C following treatment at 8 MPa. Unlike the H‐100 and H‐440, the Tm value of the REVODE tended to decrease with increasing pressure. The Tg values increased greatly under mild conditions of 8 MPa pressure and a temperature of 40 °C. In particular, the Tg values for the H‐440 and REVODE increased by 4 °C and 5 °C, respectively. All Tg values were lowest at 12 MPa and increased with increasing processing pressure, although the effect of processing temperature was minimal. The Χc DSC of the H‐100 was 18% initially but increased to 20% upon scCO2 processing at 40 °C and 14 MPa, and showed further increases at higher processing temperatures. Although the relationship between processing temperature and Χc DSC values for the H‐440 showed the same trend as observed with the H‐100, a different trend was seen for the REVODE. The Χc XRD values obtained from the XRD analyses differed from the values generated by DSC analysis, and showed a maximum degree of crystallinity following processing at 80 °C both with and without scCO2 treatment. ATR FT‐IR analyses identified peaks due to semicrystalline regions in poly(l ‐lactide) samples treated with scCO2, even when applying low temperatures. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44006. 相似文献
98.
Ryuta Shigefuku Hideaki Takahashi Hiroyasu Nakano Tsunamasa Watanabe Kotaro Matsunaga Nobuyuki Matsumoto Masaki Kato Ryo Morita Yousuke Michikawa Tomohiro Tamura Tetsuya Hiraishi Nobuhiro Hattori Yohei Noguchi Kazunari Nakahara Hiroki Ikeda Toshiya Ishii Chiaki Okuse Shigeru Sase Fumio Itoh Michihiro Suzuki 《International journal of molecular sciences》2016,17(9)
The progression of chronic liver disease differs by etiology. The aim of this study was to elucidate the difference in disease progression between chronic hepatitis C (CHC) and nonalcoholic fatty liver disease (NAFLD) by means of fibrosis markers, liver function, and hepatic tissue blood flow (TBF). Xenon computed tomography (Xe-CT) was performed in 139 patients with NAFLD and 152 patients with CHC (including liver cirrhosis (LC)). The cutoff values for fibrosis markers were compared between NAFLD and CHC, and correlations between hepatic TBF and liver function tests were examined at each fibrosis stage. The cutoff values for detection of the advanced fibrosis stage were lower in NAFLD than in CHC. Although portal venous TBF (PVTBF) correlated with liver function tests, PVTBF in initial LC caused by nonalcoholic steatohepatitis (NASH-LC) was significantly lower than that in hepatitis C virus (C-LC) (p = 0.014). Conversely, the liver function tests in NASH-LC were higher than those in C-LC (p < 0.05). It is important to recognize the difference between NAFLD and CHC. We concluded that changes in hepatic blood flow occurred during the earliest stage of hepatic fibrosis in patients with NAFLD; therefore, patients with NAFLD need to be followed carefully. 相似文献
99.
Joao Gari da Silva Fonseca Junior Takashi Oozeki Hideaki Ohtake Takumi Takashima Kazuhiko Ogimoto 《Progress in Photovoltaics: Research and Applications》2015,23(10):1203-1218
The development of methods to forecast photovoltaic (PV) power generation regionally is of utmost importance to support the spread of such power systems in current power grids. The objective of this study is to propose and to evaluate methods to forecast regional PV power 1 day ahead of time and to compare their performances. Four forecast methods were regarded, of which two are new ones proposed in this study. Together, they characterize a set of forecast methods that can be applied in different scenarios regarding availability of data and infrastructure to make the forecasts. The forecast methods were based on the use of support vector regression and weather prediction data. Evaluations were performed for 1 year of hourly forecasts using data of 273 PV systems installed in two adjacent regions in Japan, Kanto, and Chubu. The results show the importance of selecting the proper forecast method regarding the region characteristics. For Chubu, the region with a variety of weather conditions, the forecast methods based on single systems' forecasts and the one based on stratified sampling provided the best results. In this case, the best annual normalized root mean square error (RMSE) and mean absolute error (MAE) were 0.25 and 0.15 kWh/kWhavg, respectively. For Kanto, with homogeneous weather conditions, the four methods performed similarly. In this case, the lowest annual forecast errors were 0.33 kWh/kWhavg for the normalized RMSE and 0.202 kWh/kWhavg for the normalized MAE. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
100.
Shinsuke Nakayama 《Journal of Nuclear Science and Technology》2018,55(6):614-622
Toward the development of the next version of Japanese Evaluated Nuclear Data Library (JENDL) general-purpose file, we calculate neutron cross-sections on 63, 65Cu from 50 keV to 20 MeV, which is the incident energy range above the resolved resonance region in JENDL-4.0. A dispersive optical model potential is adopted with a coupled-channel method for interaction between neutron and 63, 65Cu. Direct, pre-equilibrium, and compound processes are taken into account in the calculation. All cross-sections, differential and double-differential cross-sections are consistently calculated with a single set of model parameters. The calculation results reproduce the measured data very well. In addition, disagreement between the calculated and experimental values seen in an integral test for the 63Cu(n, α)60Co reaction is improved by using the cross-section data obtained from the present work. 相似文献