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排序方式: 共有1225条查询结果,搜索用时 15 毫秒
81.
F Abe Y Iwase T Yamauchi K Kinjo S Yaga M Ishii M Iwahana 《Canadian Metallurgical Quarterly》1998,47(5):833-837
In addition to huratoxin, pimelea factor P2, and wikstroelides A-G from the fresh bark, eight daphnane-type diterpenoids, wikstroelides H-O, were isolated from the bark and stem, and their structures established. Cytotoxicity was assayed on some wikstroelides. 相似文献
82.
83.
84.
Ken Yuki Toshiaki Sato Hitoshi Maruyama Junnosuke Yamauchi Takuji Okaya 《Polymer International》1993,30(4):513-517
Emulsion polymerization of styrene (St) and vinyl acetate (VAc) in the presence of conventional polyvinyl alcohol (PVA), PVA modified with a terminal alkyl group or PVA modified with a terminal thiol group (HS-PVA) was compared. Whereas stable PVAc latexes were obtained, a stable PSt latex was obtained only in the case of HS-PVA. From the adsorption isotherms of these PVAs on the surface of PVAc and PSt latex particles, as well as the grafting efficiencies of VAc and St onto HS-PVA in relation to the stability of the polymerization process, the role of PVA in the emulsion polymerization was discussed. 相似文献
85.
86.
The relationships between 4-hydroxy-2-nonenal (HNE), 2-thiobarbituric acid reactive substances (TBARS) and n-6 polyunsaturated fatty acids (n-6 PUFAs) were investigated for pork stored at 0, -20 and -80 degrees C. A significant linear correlation was apparent between HNE and TBARS for the pork stored at each temperature. However, the n-6 PUFA content remained unchanged during storage. 相似文献
87.
T Tsukamoto T Fujioka T Yamauchi Y Mori I Nagakubo 《Canadian Metallurgical Quarterly》1997,88(8):746-751
The use of proxy respondents in surveys designed to provide population estimates of smoking prevalence offers an inexpensive way to obtain these data. The accuracy of this information is examined in analyzing data from tobacco use surveys of adults conducted in 22 North American communities as part of the National Cancer Institute's Community Intervention Trial for Smoking Cessation. Proxy-reported smoking status was obtained in a cross-sectional telephone survey conducted from August 1993 to January 1994 (n = 99,682). Self-reported smoking status was obtained from an in-depth interview of a sample of the respondents aged 25-64 years enumerated from the telephone survey (n = 31,417). Discrepancy rates were calculated by comparing the proxy-reported and self-reported smoking statuses of a given individual (n = 10,226). In both surveys, respondents were categorized as current smokers (those who currently smoke and have smoked at least 100 cigarettes in their lifetime), recent quitters (< or = 8 years since cessation), long-term quitters (> 8 years since cessation), and never smokers. The overall discrepancy rate between the self-report and the proxy report was 5.4%. Self-respondents who were black, Hispanic, Asian, recent quitters, or aged 25-34 years were more likely to have inconsistent proxy reports. The authors estimate that the screener interview underestimated the true smoking prevalence by 0.1% when they corrected for smoking status discrepancies. These results confirm that proxy-reported smoking status is an accurate and effective means to monitor populationwide smoking prevalence of adults. 相似文献
88.
Hatakeyama K. Yamauchi K. Tsutaoka T. Nakamura T. Ehrich M. 《Electromagnetic Compatibility, IEEE Transactions on》2002,44(2):347-352
Scattering wave suppression by ferrite composite coating on long, thin metal rods is presented. The coating effect depends on not only the material permeability and thickness, but also on the incident and scattering directions. Numerical results are given at 1, 3, and 10 GHz. At 10 GHz, experimental results are also presented 相似文献
89.
90.
Morita Shigeru Fujita Junji 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1985,9(4):713-723
X-ray spectra for several elements have been observed from a high-temperature plasma produced in a vacuum spark using a curved-crystal spectrometer. The transition wavelengths of the He-like resonance lines for Ti through Zn are determined for the first time under careful experimental treatments. The result is compared with theoretical predictions. The transition wavelengths of the Fe He-like resonance series lines up to 1s6p–1s2 and the Kβ transition energies of Ti partially M-shell-ionised ions (Ti VI–XIII) are also determined. As a result, several satellite lines are found. 相似文献