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排序方式: 共有6177条查询结果,搜索用时 93 毫秒
941.
Y. Zhai R. Feder A. Brooks M. Ulrickson C.S. Pitcher G.D. Loesser 《Fusion Engineering and Design》2013,88(6-8):547-550
ITER diagnostic port plugs perform many functions including structural support of diagnostic systems under high electromagnetic loads while allowing for diagnostic access to the plasma. The design of diagnostic equatorial port plugs (EPP) are largely driven by electromagnetic loads and associate responses of EPP structure during plasma disruptions and VDEs. This paper summarizes results of transient electromagnetic analysis using Opera 3d in support of the design activities for ITER diagnostic EPP. A complete distribution of disruption loads on the diagnostic first walls (DFWs), diagnostic shield modules (DSMs) and the EPP structure, as well as impact on the system design integration due to electrical contact among various EPP structural components are discussed. 相似文献
942.
矸石充填是当前煤矿生产中常用的一种充填方式,用于液压支架后部的矸石捣实机构是充填工作的关键设备。矸石捣实机构有单级捣实机构和双级捣实机构,其支撑方式有下部推拉及上部吊挂等多种形式。根据现场使用经验,对结构进行了分析,并对充填开采方法提出一点建议。 相似文献
943.
A large amount of TiC hexagonal platelets has formed on the surface of the sample made of Ti/Si/TiC/Al0.2 after sintering at above 1450 °C in an Ar atmosphere. The basal plane of TiC platelets is (111) facet confirmed by X-ray diffraction. Small amounts of Si and Al elements dissolved in the TiC crystal structure, influencing the structure of TiC. The detailed structure and growth mechanism of the TiC platelets have been observed and analyzed. A model has been proposed to understand the formation of TiC hexagonal platelets. 相似文献
944.
Daishuang Li Jing Peng Maolin Zhai Jinliang Qiao Xiaohong Zhang Genshuan Wei 《应用聚合物科学杂志》2008,109(4):2071-2075
By using in situ prepolymerization and radiation curing, high‐impact polystyrene (HIPS) with a bimodal distribution of the size of the rubber particles (bimodal HIPS) was synthesized in the presence of ultrafine full‐vulcanized powdered styrene–butadiene rubber (UFPSBR) and polybutadiene rubber (BR). TEM photographs indicated that UFPSBR was dispersed uniformly as a single particle with a diameter of about 100 nm. On the other hand, bimodal HIPS with different rubber particle size distributions could also be obtained by blending HIPS and UFPSBR grafting styrene (UFPSBR‐g‐St) with different grafting yields. The bimodal HIPS with the smallest rubber particle size, at about 100 nm, could be prepared by blending the monomodal HIPS containing big rubber particles with polystyrene/UFPSBR. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
945.
Feng Xu Run‐Cang Sun Mei‐Zhi Zhai Jin‐Xia Sun Jian‐Xin Jiang Guang‐Jie Zhao 《应用聚合物科学杂志》2008,108(2):1158-1168
Six lignin fractions from mild ball‐milled Tamarix austromogoliac (TA) and Caragana sepium (CS) were sequentially isolated with 80% dioxane containing 0.05M HCl at 75°C for 4 h, 50% aqueous ethanol containing 1M triethylamine at 70°C for 4 h, and 8% aqueous NaOH at 45°C for 3 h. The results showed that the successive treatments made it possible to isolate lignin from wood with a high yield and purity, in which 89.4 and 90.6% of the original lignin from TA and CS were released, respectively. The lignin fractions isolated with the three‐step method were analyzed with Fourier transform infrared, 1H‐ and 13C‐NMR, alkaline nitrobenzene oxidation, and gel permeation chromatography. It was found that the three lignin fractions isolated from TA were rich in syringyl units, and the molar ratio of the relatively total moles of vanillin, vanillic acid, and acetovanillin to the relatively total moles of syringaldehyde, syringic acid, and acetosyringone decreased from 1: 2.6 to 1 : 3.2 to 1: 3.6 in the lignin preparations, whereas this ratio in the corresponding lignin fractions isolated from CS was found to be 1.4 : 1, 1.1 : 1, and 1 : 1.4, respectively. More importantly, the results revealed that the sequential extractions of the mild ball‐milled TA and CS with 80% acidic dioxane, 50% alkaline ethanol, and 8% aqueous NaOH under the conditions used did not significantly cleave the β–O‐4 and α–O‐4 linkages in lignin macromolecules. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
946.
947.
948.
Guohua Wu Yu Fan Andrej Atrens Chunquan Zhai Wenjiang Ding 《Journal of Applied Electrochemistry》2008,38(2):251-257
The influence of Cl− and SO42− on the electrochemical behavior of AZ91D, AZCe2, and AZLa1 was studied. For all alloys, there was a current plateau in the
anodic polarization curves in Na2SO4 solutions. In 0.5% NaCl solution, there was a small current plateau, whereas there was none in the 3.5% and 5% NaCl solutions.
This indicated that SO42− is less aggressive than Cl−. The range of the current plateau decreased with increasing SO42− concentration. For all alloys, the high frequency capacitive loop in the Nyquist plots decreased with increasing concentration
consistent with the decrease in corrosion resistance with increasing Cl− and SO42− concentration. 相似文献
949.
950.
该文从实地调查淄博市“美食街”地段中的流动商贩入手,对流动商贩的经营商品和辅助工具的种类、地段中的用地性质、消费者购买路线、地段中的道路宽度四个影响流动商贩分布的因素进行了研究和分析,从而寻找和总结出流动商贩存在的必要性以及其在哪些层面影响了我们的城市,以便对流动商贩提出合理的规划布局原则和人性化的管理建议。 相似文献