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31.
Watanabe T Zhang ZW Qu JB Gao WP Jian ZK Shimbo S Nakatsuka H Matsuda-Inoguchi N Higashikawa K Ikeda M 《The Science of the total environment》2000,247(1):1-13
The objectives of the present study are: (a) to clarify the current levels of environmental exposure to lead (Pb) and cadmium (Cd) in Shaanxi Province in China in comparison with levels in other parts of mainland China; (b) to examine if there is any urban-rural difference in Pb and Cd exposure; and (c) to quantify the role of cereals as the dietary source of environmental exposure to these metals. For this purpose, triplet surveys on lead and cadmium exposure were conducted in the provincial capital of Xian and two farming villages A and B in Shaanxi Province, China in 1997. The grand geometric mean for lead (Pb) intake via foods (Pb-F), Pb in blood (Pb-B) and Pb in urine as corrected for creatinine concentration (Pb-Ucr) were 30 micrograms/day, 33 micrograms/l and 5 micrograms/g creatinine, respectively, with significant differences among the survey sites, e.g. Pb-B being higher in Xian (43 micrograms/l) than in the two villages (38 and 22 micrograms/l). The counterpart values for cadmium (Cd) intake via foods (Cd-F), Cd in blood (Cd-B) and Cd in urine (Cd-Ucr) were 6.1 micrograms/day, 0.46 microgram/l and 2.8 micrograms/g creatinine, respectively, with no substantial inter-survey site difference. Thus, it was possible to conclude that, from comparison with the values reported in 1990s literature, the exposure of Shaanxi people to Pb and Cd is no higher than, and even possibly lower than, the levels reported for people in other parts of mainland China. The exposure to Cd was almost exclusively from foods, whereas the exposure to air-borne Pb was large enough in Xian to explain higher Pb-B and Pb-Ucr than the level in Village B despite lower Pb-F in Xian than in Village B. Cereals (wheat, rice, maize and foxtail millet) contributed 26 and 84% of dietary Pb and Cd intake, respectively. 相似文献
32.
小型高速艇的减振降噪是近几年经起重视的,本文通过对间接的,有限的噪声振动源资源的分析研究,预估了一类小型高速艇各舱室的噪声级,根据国外近期同类艇的噪声水平以及总体减振降噪和多方面约束条件综合测定了该艇的减振降噪方案,并在此基础上进行了声强激励和振动激励条件下舱室模型综合减振降噪效果试验,结果表明,所制定的减振降噪方案其效果良好,实艇实测结果达到设计指标要求。 相似文献
33.
The flux growth of emerald crystals by slow cooling in the PbO · V2O5 flux is reported. The crystals exhibited the typical emerald-green colour, were up to 1.8 mm in size and transparent. Their
form was a regular hexagonal rod bounded by the well-developed {0001} and {10ˉ10} faces. The solubility of emerald in PbO
· V2O5 was also investigated; about 9.0 g emerald was dissolved in 100 g PbO · V2O5 at 1200 °C. The solubility decreased gradually with decreasing temperature. Taking the solubility data into account, the
presence of undissolved particles in the solution was found to be a necessary condition for the growth of large emerald crystals.
Unsaturated solution at a soak temperature produced good and relatively small emerald crystals in a subsequent cooling experiment.
Advantages of the PbO · V2O5 flux are also mentioned. Emerald crystals showing various kinds of imperfections, and even good crystals, were also present. 相似文献
34.
Shuji Nakajima Mutsuto Kawahara 《Computer Methods in Applied Mechanics and Engineering》2010,199(49-52):3111-3124
The objective of this study is to determine the two dimensional shape of a body located in a compressible viscous flow, where the applied fluid force is minimized. The formulation to obtain the optimal shape is based on an optimal control theory. An optimal state is defined as a state, in which the performance function defined as the integration of the square sum of the applied fluid forces is minimized due to a reduction in the applied fluid forces. Compressible Navier–Stokes equations are treated as constraint equations. In other words, the body is considered to have a shape that minimizes the fluid forces under the constraint of the Navier–Stokes equations. The gradient of the performance function is computed using the adjoint variables. A weighted gradient method is used as the minimization algorithm. The volume of the body is assumed to be the same as that of the initial body. In the case of the algorithm used in this study, both the creation of a structured mesh around the surface of the body and the smoothing procedure are employed for the computation of gradient. In this study, a remeshing technique based on the structured mesh around the body changing its configuration in the iteration cycle is employed. For the correction to keep the volume constant, the surface coordinates are moved along the radial direction. For the discretization of both the state and adjoint equations, the efficient bubble function interpolation presented previously by the authors [18] is employed. The algorithm, which is known as the partial control algorithm, is applied to the numerical procedure to determine the movement of the coordinates. In the case of the gradient method, in order to avoid the convergence of the final shape to the local minimum shape, the new algorithm, which is called the partial control algorithm, is presented in this study. In numerical studies, the shape determination of a body in a uniform flow field is carried out in 2D domains. The initial shape of the body is assumed to be an elliptical cylinder. The shape is modified by minimizing the applied fluid forces. Finally, the desired shape of a body, whose performance function is reduced and converged to a constant value, is obtained. By carrying out a procedure that involves the use of the partial control algorithm, the desired shape of a body, whose performance function is reduced further, is obtained. Stable shape determination of a body in a compressible viscous flow is carried out by using the presented method. It is indicated that the optimal shape can be obtained by using the partial control algorithm. 相似文献
35.
36.
Shingo Hasegawa Shuji Isobe Hiroki Shizuya Katsuhiro Tashiro 《International Journal of Information Security》2009,8(5):347-355
The notion of pseudo-free group was first introduced by Hohenberger (Master’s thesis, EECS Dept., MIT, 2003). Rivest (TCC
2004. LNCS 2951, 505–521, 2004) formalized it and showed that several standard cryptographic assumptions hold on pseudo-free groups, such
as the RSA assumption, the strong RSA assumption and the discrete logarithm assumption. Rivest (TCC 2004. LNCS 2951, 505–521, 2004) also proposed some variations of pseudo-free group, and those were formalized by Hirano and Tanaka (Research
Reports, Series C: Computer Science, C-239, Tokyo Institute of Technology, 2007). In this paper, we study the relationships
among such variations of pseudo-free group. We show that the pseudo-freeness implies the weak pseudo-freeness, and that the
pseudo-freeness is equivalent to the pseudo-freeness with generalized exponential expressions. We also show that the computational
Diffie-Hellman assumption holds on pseudo-free groups in a slightly varied form. 相似文献
37.
The effects of infusion of trieicosapentaenoyl-glycerol emulsion on extravascular lung water during myocardial ischemia and reperfusion in dogs 总被引:2,自引:0,他引:2
Toshio Izuoka Yutaka Kimura Tomohito Hamazaki Teruhiro Tamura Shuji Kitashiro Tetsuro Sugiura Toshimitsu Jikuhara Toshiji Iwasaka 《Lipids》1997,32(1):109-114
To test the effects of eicosapentaenoic acid (EPA) infusion on pulmonary edema induced by coronary ligation and reperfusion,
extravascular lung water (EVLW) was measured in situ by the thermal-dye double indicator dilution method in dogs. In the control group of five dogs, 30 mL of a 10% soybean oil
emulsion was infused through a leg vein. One hour after infusion, the left anterior descending coronary artery below the first
diagonal branch was ligated for 15 min and then reperfused for 30 min. In the EPA group, six dogs were similarly treated with
an emulsion of a 10% trieicosapentaenoyl-glycerol (90% pure). EVLW, pulmonary capillary wedge pressure, mean pulmonary artery
pressure, mean blood pressure, and cardiac index were measured before and 15 min after coronary ligation, and 15 min and 30
min after coronary reperfusion. There were no significant differences in the hemodynamic indices between the two groups. EVLW
significantly increased up to two times of baseline during coronary ligation in the control group (P< 0.05) and more during reperfusion (P<0.01), whereas EVLW did not increase in the EPA group. In conclusion, EPA inhibited EVLW accumulation and may be useful for
ameliorating one of the ischemia-reperfusion-induced complications, pulmonary edema. 相似文献
38.
Kyosuke Yoshimi Shuji Hanada 《JOM Journal of the Minerals, Metals and Materials Society》1997,49(8):46-49
For the development of Fe−Al alloys as structural materials, a deep understanding of slip and deformation properties is necessary.
In particular, since mechanical properties of the iron aluminides are affected by excess vacancy strengthening as well as
the positive-temperature dependence of yield stress, controlling these strength features is essential. In this article, the
strength properties of iron aluminides are reviewed.
Author’s Note: All compositions are provided in mole percent.
Kyosuke Yoshimi earned his Ph.D. in materials science and engineering at Tohoku University in 1997. He is currently a research associate
at Tohoku University.
Shuji Hanada earned his Ph.D. in materials science and engineering at Tohoku University. He is currently a professor at Tohoku University.
Dr. Hanada is also a member of TMS. 相似文献
39.
Black rice bran was treated by water and subcritical water at temperatures ranging from 20 to 260 °C for 5 min and at 200 and 260 °C for 5-120 min. The bran extracts were analyzed for their radical scavenging activity, protein and carbohydrate contents, molecular-mass distribution, antioxidation activity, emulsifying activity, and emulsion-stabilizing activity. The radical scavenging activity and the protein content of the extract were higher at higher treatment temperature. The carbohydrate content also increased with increasing temperature up to 200 °C, then steeply decreased at the temperatures higher than 200 °C. The bran extracts treated at 260 °C for 5 min exhibited a suppressive activity toward autoxidation of linoleic acid with the increasing the weight ratio of the bran extract to linoleic acid. The bran extracts prepared at 40-200 °C for 5 min showed the emulsifying- and emulsion-stabilizing activities, while the extracts prepared at 220-260 °C were low in the activities. 相似文献
40.
Satoshi Kubo Koh Hashida Shojiro Hishiyama Tatsuhiko Yamada Shuji Hosoya 《木材化学与工艺学杂志》2015,35(1):62-72
In the alkaline decomposition of a β-O-4 type lignin model compound (erythro-guaiacylglycerol-β-guaiacyl ether, compound 1), an isomeric pair of C6C2 enol-ether (2-methoxy-4-[2-(2-methoxyphenoxy)-vinyl]-phenol, compound 2) was detected as the main decomposition product with no trace of C6C3 enol-ether (4-[3-hydroxy-1-(2-methoxyphenoxy)-propenyl]-2-methoxy-phenol, compound 3) or other dimers. In contrast, compound 2 was not detected in the alkaline decomposition products of compound 3. Under alkaline conditions, the γ-hydroxymethyl group of compound 3 was reduced to form 2-methoxy-4-[1-(2-methoxyphenoxy)-propenyl]-phenol (compound 4). In the HSQC analysis of soda lignin, the formation of substructures of C6C2 type enol-ether (related to compound 2) was confirmed. However, no substructures related to compound 4, which could be formed if a substructure of C6C3 type enol-ether was formed under alkaline conditions, were detected. Therefore, it could be concluded that C6C3 type enol-ethers could not be intermediates of alkaline decomposition products of lignin. 相似文献