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排序方式: 共有534条查询结果,搜索用时 15 毫秒
11.
Jianding Yu Yan Liu Xiuhong Pan Hongyang Zhao Velu Nirmal Kumar Mukannan Arivanandhan Yoshimi Momose Yasuhiro Hayakawa Xingwang Zhang Xinghong Luo Yasuhiro Okano Yuko Inatomi 《Microgravity science and technology》2016,28(2):143-154
The paper reviewed the previous microgravity experiment using Chinese recovery satellite, the in-situ measurement of composition profile in the solution by X-ray penetration method and homogeneous growth of InGaSb by temperature freezing method under terrestrial condition for making clear the effect of gravity on the growth of InGaSb ternary alloy semiconductor crystals. The previous experimental results showed that the shape of solid/liquid interfaces and composition profile in the solution were significantly affected by gravity. Based on the previous microgravity experimental results, experimental conditions were investigated to grow homogeneous In xGa 1?xSb with higher indium composition at Chinese recovery satellite SJ-10 in near future. 相似文献
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Xingwang Zhao Jingnan Sun Sumei Liu Zhengwei Long Yonggao Yin Qingyan Chen 《Indoor air》2021,31(5):1614-1624
Currently, the thermal environment in airplane cockpits is unsatisfactory and pilots often complain about a strong draft sensation in the cockpit. It is caused by the unreasonable air supply diffusers design. One of the best approaches to design a better cockpit environment is the adjoint method. The method can simultaneously and efficiently identify the number, size, location, and shape of air supply inlets, and the air supply parameters. However, the real air diffuser needed to design often have grilles, especially in the airplane cockpit, and the current method can only design the inlet as an opening. This study combined the adjoint method with the momentum method to directly identify the optimal air supply diffusers with grilles to create optimal thermal environment in an airplane cockpit (1) under ideal conditions and (2) with realistic constraints. Under the ideal conditions, the resulting design provides an optimal thermal environment for the cockpit, but it might not be feasible in practice. The design with realistic constraints provides acceptable thermal comfort in the cockpit, but it is not optimal. Thus, there is an engineering trade-off between design feasibility and optimization. All in all, the adjoint method with the momentum method can be effectively used to identify real air supply diffusers. 相似文献
14.
Based on non-Darcian flow caused by non-Newtonian liquid, the theory of one-dimensional (1D) consolidation was modified to consider variation in the total vertical stress with depth and time. The finite difference method (FDM) was adopted to obtain numerical solutions for excess pore water pressure and average degree of consolidation. When non-Darcian flow is degenerated into Darcian flow, a comparison between numerical solutions and analytical solutions was made to verify reliability of finite difference solutions. Finally, taking into account the ramp time-dependent loading, consolidation behaviors with non-Darcian flow under various parameters were analyzed. Thus, a comprehensive analysis of 1D consolidation combined with non-Darcian flow caused by non-Newtonian liquid was conducted in this paper. 相似文献
15.
D. A. Derusova V. P. Vavilov Xingwang Guo V. Yu. Shpil’noi N. S. Danilin 《Russian Journal of Nondestructive Testing》2018,54(10):733-739
Ultrasonic infrared thermography is a rapid and informative method of nondestructive testing, used to inspect materials and products in aviation and rocket and space industries. High-power piezoelectric emitters stimulate various materials by ultrasound and help revealing hidden flaws by local temperature changes, which can amount to tens of degrees. The possibility of optimizing the procedure of ultrasonic infrared thermography by choosing the frequency of acoustic waves so as to match the frequencies of local resonances of defects of different sizes has been investigated. 相似文献
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根据电动机的实例来说明如何正确的选择使用滚动轴承并加以配置,并分析其优缺点。证明了电动机轴承配置的正确会延长电机轴承的使用寿命,进而提高电动机的使用寿命。 相似文献
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本工作采用2 MeV He+在300℃下对Zr-0.75Sn-0.35Fe-0.15Cr-x Nb(x=0,1.0,mass fraction,%)合金进行辐照,然后在360℃/18.6 MPa/0.01 mol/L LiOH水溶液中进行高压釜腐蚀实验,利用扫描电子显微镜和透射电子显微镜研究辐照对合金显微组织及腐蚀行为的影响。结果表明,添加Nb改变了Zr-0.75Sn-0.35Fe-0.15Cr合金中第二相的数量、尺寸和晶体结构。He+辐照1 dpa后,合金的辐照损伤峰区域分布有大量的He泡和型位错环,添加Nb对He泡和位错环的数量及第二相的元素扩散等均产生了一定的影响。腐蚀结果表明,He+辐照或添加1.0%的Nb均可促进Zr-0.75Sn-0.35Fe-0.15Cr合金的腐蚀,但当二者同时存在时,辐照能减弱Nb促进腐蚀的作用。 相似文献
18.
以环氧树脂(EP)为连续相、橡胶材料为分散相,制备了一种EP/橡胶弹性混凝土材料。着重考察了橡胶材料的组成、m(EP)∶m(橡胶)比例对弹性混凝土密度和力学性能的影响。研究结果表明:橡胶材料组成、m(EP)∶m(橡胶)比例对弹性混凝土密度的影响均不大(密度为1.020~1.070 g/cm3);随着橡胶材料中橡胶颗粒含量的不断减少,弹性混凝土的压缩弹性模量基本不变,压缩强度和弯折强度均略有提高;随着m(EP)∶m(橡胶)比例的不断减少,弹性混凝土的压缩弹性模量、压缩强度和弯折强度均显著降低。 相似文献
19.
高效液相色谱串联质谱测定武夷岩茶中草甘膦残留量的方法探讨 总被引:2,自引:0,他引:2
采用高效液相色谱串联质谱建立了武夷岩茶样品中草甘膦的残留量的测定方法。样品经水固相萃取和茶叶专用萃取柱(TPT)净化后,在硼酸盐缓冲液中与9-芴甲基氯甲酸酯(FMOC-Cl)进行衍生化反应,以1%乙酸铵溶液和乙腈为流动相,质谱检测采用电喷雾正离子化模式和多反应监测模式。结果表明,草甘膦在1~10 ng/mL范围内线性良好,线性相关系数r=0.998。通过对空白武夷岩茶样品进行4个加标水平的添加回收实验(n=5),草甘膦的平均回收率和相对标准偏差(RSD)分别为87.3%~98.0%和3.46~5.12。 相似文献
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