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31.
Amakura Y Tsutsumi T Iida T Nakagawa R Hori T Tobiishi K Uchibe H Nakamura M Yanagi T Kono Y Toyoda M Sasaki K Maitani T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2005,46(4):148-152
To examine dioxin contamination in commercial baby foods in Japan, congener analyses of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (Co-PCBs) were performed on 102 varieties of baby foods obtained from supermarkets in 2001-2002. The toxic equivalent quantity (TEQ) levels for dioxins in samples ranged from < 0.001 to 0.135 pg-TEQ/g wet weight when undetected or trace levels of congeners were taken as zero. Among 102 samples tested, 26 samples exceeded 0.010 pg-TEQ/g. The highest TEQ value was for "sardine, vegetables" (0.135 pg-TEQ/g), followed by "Japanese radish (daikon), sardine" (0.080 pg-TEQ/g). Thus, dioxins were detected at low levels in baby foods containing animal products such as fishes and/or dairy products. 相似文献
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33.
The double-inlet pulse tube refrigerator that has a diaphragm inserted in a bypass-tube, which enabled it to transmit a pressure oscillation whereas to obstruct a DC gas flow, was manufactured and tested. The oscillating flow behavior inside of the refrigerator was studied by using a smoke-wire flow visualization technique. It was found that if the diaphragm was optimized, the performance would be improved more than that of the refrigerator with a bypass valve due to the increase in the P–V work of the gas and the decrease in the convective heat loss caused by a secondary flow. 相似文献
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35.
A Two‐Stage Stochastic Mixed‐Integer Programming Approach to the Smart House Scheduling Problem 下载免费PDF全文
A “smart house” is a highly energy‐optimized house equipped with photovoltaic (PV) systems, electric battery systems, fuel cell (FC) cogeneration systems, electric vehicles (EVs), and so on. Smart houses are attracting much attention recently because of their enhanced ability to save energy by making full use of renewable energy and by achieving power grid stability despite an increased power draw for installed PV systems. Yet running a smart house's power system, with its multiple power sources and power storages, is no simple task. In this paper, we consider the problem of power scheduling for a smart house with a PV system, an FC cogeneration system, and an EV. We formulate the problem as a mixed‐integer programming problem, and then extend it to a stochastic programming problem involving recourse costs to cope with uncertain electricity demand, heat demand, and PV power generation. Using our method, we seek to achieve the optimal power schedule running at the minimum expected operation cost. We present some results of numerical experiments with data on real‐life demands and PV power generation to show the effectiveness of our method. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(4): 48–58, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22336 相似文献
36.
Masuda Takahiro Fujimitsu Kazushige Sumikawa Kosei Kajita Takahiro Tang Yongpeng Hirosawa Shoichi Takizawa Yoichi Yumoto Manabu Otagiri Yoshiharu Horita Zenji 《Metallurgical and Materials Transactions A》2021,52(9):3860-3870
Metallurgical and Materials Transactions A - This study examines strain distribution occurring in the high-pressure sliding (HPS) processing for rods of pure Al and an AZ61 alloy. The strain... 相似文献
37.
Kiyoshi Oguchi Kohei Sanui Naoya Ogata Yoichi Takahashi Tomihiro Nakada 《Polymer Engineering and Science》1989,29(6):353-358
Acetalized poly(vinyl alcohol)s which were synthesized from poly(vinyl alcohol) (PVA) and aldehyde or ketone were evaluated as electron beam (EB) resists, in order to investigate the relationship between EB sensitivity and chemical structures of the polymers. It was found that the acetalized PVAs were easily crosslinked by EB exposure. The main mechanism of crosslinking may be radical reaction at acetal group. The sensitivity of the acetalized PVA depended on the structure of the acetal group. Acetalized PVAs synthesized from benzaldehyde, in which the electron attracting group was substituted on the benzene ring and from linear aliphatic aldehyde having a long alkyl chain, had high sensitivity. A high sensitivity of 7.2 × 10−7 C/cm2 was attained when the acetalized PVA synthesized from p-chloro-benzaldehyde was used. Acetalized PVAs synthesized from PVA and aldehyde having a cyclic structure had an excellent dry etching durability and were suitable as negative EB resists. 相似文献
38.
Fumihide Shiraishi Koei Kawakami Hiroshi Marushima Koichiro Kusunoki 《Starch - St?rke》1989,41(11):417-420
Effects of aliphatic alcohols such as ethanol, n-butanol and n-decanol on the formation of cyclodextrin (CD) from soluble starch by Bacillus macerans cyclodextrin glucanotransferase (CGTase) were experimentally studied at 50°C and pH 6.0. The addition of such aliphatic alcohols caused an increase in α-CD yield, which extent was remarkable in n-butanol. From the incubation of α-CD with CGTase, such an increase was found to be due to a restriction on further transglycosylation of α-CD into β-CD by CGTase imposed by the aliphatic alcohols. 相似文献
39.
Kazuo Hasue Shoji Nakahara Jun Morimoto Tetsuo Yamagami Yoichi Okamoto Toru Miyakawa 《Propellants, Explosives, Pyrotechnics》1995,20(4):187-191
To find an effective laser source to ignite energetic materials, the absorption spectra of some energetic materials are obtained by means of a photoacoustic spectroscopy (PAS). In this experiment, PAS covers the wavelength region of 400 nm-1600 nm in which no other conventional method can take absorption spectra for powdered energetic materials. Photoacoustic spectra of 18 energetic materials are reported. In general, energetic materials tested showed peaks in 600 nm–800 nm and 1400 nm–1600 nm ranges. It is found that the energy required to initiate explosives in the case of ruby laser initiation were correlated with their photoacoustic signal intensities. 相似文献
40.
Yoichi Tominaga 《Polymer》2005,46(19):8113-8118
We have measured ionic conductivity of PEO-LiX [anion X=N(CF3SO2)2 (TFSI), ClO4, CF3SO3, BF4, NO3, and CH3SO3] polymer electrolytes in CO2 at pressures varied from 0.1 to 20 MPa. From the temperature dependence in supercritical CO2, a large increase in the conductivity for PEO-LiBF4 and LiCF3SO3 electrolytes has been observed. Permeation of the CO2 molecules gave rise to the plasticization for crystal domains in the electrolytes, which is related to the reduction in transition point of the Arrhenius plot corresponding to the melting of crystal PEO. Relation between the conductivity and CO2 reduced density revealed that the electrolytes containing fluorinated anions such as ‘CO2-philic’ BF4 and CF3SO3 increase in the conductivity with increasing the density. This indicates that the salt dissociation was promoted by the CO2 permeation and the Lewis acid-base interactions between fluorinated anions and CO2 molecules. 相似文献