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排序方式: 共有1336条查询结果,搜索用时 15 毫秒
101.
Ishiwata H Abe Y Kubota H Kawasaki Y Takeda Y Maitani T Nishijima M Fukasawa Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(1):49-56
The mean concentrations and daily intake of four antifungal agents were estimated based on the results of an analysis of 7,005 samples of food obtained in official inspections by Japanese local governments in fiscal year 1998. The mean concentration of diphenyl was 0.0004% of the allowable limit, and those of imazalil, o-phenylphenol, and thiabendazole were 14.0%, 3.5%, and 5.7%, respectively. The daily intakes of these antifungal agents per person, estimated from their concentrations and the daily consumption of the foods, were 0.000326, 1.89, 11.5, and 23.3 micrograms, respectively, and assuming a body weight of 50 kg, the amounts of these antifungal agents consumed were 0.000013%, 0.15%, 0.12%, and 0.47% of the acceptable daily intake, respectively. These values are similar to the values obtained on the basis of the results of the official inspection in fiscal years 1994 and 1996, except that the amount of diphenyl is much lower (1/100). 相似文献
102.
Yu Matsuda Toru Uchida Suguru Suzuki Ryota Misaki Hiroki Yamaguchi Tomohide Niimi 《Microfluidics and nanofluidics》2011,10(1):165-171
For the development of micro- and nano-technology, it has been strongly desired to understand thermo-fluid phenomena inside
or around micro- and nano-devices. An optical measurement technique based on the absorption and the emission of photons by
molecules is useful for experimental analyses of thermo-fluid phenomena of micro and nanoflows. The pressure-sensitive paint
(PSP) technique is a potential diagnostic tool for pressure measurements of micro/nano gas flows because it works as a so-called
“molecular sensor”. However, the micro-scale measurement of PSP has been limited by the aggregation of the luminescent molecules
and their thick film due to the use of a polymer binder. In our previous work, we adopted the Langmuir–Blodgett (LB) technique
to fabricate pressure-sensitive molecular film (PSMF) with ordered molecular assemblies, and investigated properties of PSMF.
In this study, a novel approach to enhance the luminescent intensity of PSMF is proposed, and the pressure distribution in
a micro-nozzle is successfully measured by using PSMF. Moreover, we compared the pressure distribution measured by PSMF with
that numerically analyzed by the direct simulation monte carlo (DSMC) method, showing good agreement with each other. 相似文献
103.
104.
105.
Syusaku Koie Gentaro Tanaka Hiroki Fukumoto Take-aki Koizumi Takakazu Yamamoto 《Reactive and Functional Polymers》2013,73(9):1180-1187
π-Conjugated polymers based on 1-aminopyrrole and 4-amino-1,2,4-triazole were prepared. Pd-catalyzed organometallic polycondensation gave poly(arylene-ethynylene) (PAE)-type π-conjugated polymers consisting of BOC-protected 4-amino-1,2,4-triazole (Taz(BOC)) units (BOC = t-butoxycarbonyl). The number average molecular weights (Mn) were determined to be 5200–19,200 using GPC. An alternating copolymer of Taz(BOC) and bithiophene (Th–Th) units, P(Taz(BOC)-Th-Th)n-Pd, with an Mn of 10,800 was also prepared by Pd-catalyzed organometallic polycondensation. (Taz(BOC)-Th-Th)n-Pd showed a UV–Vis absorption peak at λmax = 425 nm, which is reasonable for a π-conjugated five-membered ring polymer with a coplanar structure. The deprotection of the BOC group of the polymers proceeded at 200 °C; this BOC-deprotection was investigated using a model compound. The optical and electrochemical properties of the π-conjugated polymers are reported. 相似文献
106.
K Nakata H Gotoh J Watanabe T Uetake I Komuro K Yuasa S Watanabe R Ieki H Sakamaki H Akiyama S Kudoh M Naitoh H Satoh K Shimada 《Canadian Metallurgical Quarterly》1999,93(2):667-673
After allogeneic bone marrow transplantation (allo-BMT), recipient alveolar macrophages (AM) are gradually replaced by AM of the donor origin. An influx of mononuclear phagocytes of donor origin to the lung is responsible for the repopulation, but the detailed kinetics remain unclear. We therefore studied 24 BMT recipients who underwent bronchoalveolar lavage (BAL) from 24 to 83 days after BMT. AM cell number, size, morphology, proliferating ability, and genotype of AM were measured. Before day 50, the number and size of AM in BAL fluid were similar to those of normal nonsmokers. However, after day 50, the mean number of AM increased threefold and the mean cell size decreased due to the increase of small AM. These small cells are presumably of donor origin based on DNA fingerprinting analysis and based on fluorescence in situ hybridization for the Y chromosome in a sex-mismatched case. Immunohistochemistry and cell cycle analysis demonstrated that the increase in AM number coincided with a remarkable increase of AM expressing proliferating cell nuclear antigen, suggesting that small AM are proliferating. This is the first report representing that augmented proliferation of donor AM in situ may contribute to the reconstitution of AM population after BMT. 相似文献
107.
108.
Single-wall carbon nanotubes were grown by thermal chemical vapor deposition using either boron- or nitrogen-containing feedstocks or both. Carrier doping was evidenced by hardenings of the G band in Raman spectra, and the estimated carrier concentration reached ∼0.4%. In the G′ and D band spectra, a doping-induced component was observed at the high- or low-energy side of the original one. However, the appearance of the new component did not always coincide with the carrier doping. The doped SWCNTs often show radial breathing mode peaks in the off-resonance region, indicating a defect-induced modification of absorption spectrum. 相似文献
109.
110.
Koichi DoiSatoshi Hino Hiroki MiyaokaTakayuki Ichikawa Yoshitsugu Kojima 《Journal of power sources》2011,196(1):504-507
A lithium silicon alloy was synthesized by mechanical alloying method. Hydrogen storage properties of this Li-Si-H system were studied. During hydrogenation of the lithium silicon alloy, lithium atom was extracted from the alloy and lithium hydride was generated. Equilibrium hydrogen pressures for desorption and absorption reactions were measured in a temperature range from 400 to 500 °C to investigate the thermodynamic characteristics of the system, which can reversibly store 5.4 mass% hydrogen with smaller reaction enthalpy than simple metal Li. Li absorbing alloys, which have been widely studied as a negative electrode material for Li ion rechargeable batteries, can be used as hydrogen storage materials with high hydrogen capacity. 相似文献