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81.
A dense Ba0.5Sr0.5Co0.8Fe0.2O3-δ membrane tube was prepared by the extruding method. Furthermore, a membrane reactor with this tubular membrane was successfully applied to partial oxidation of methane (POM) reaction, in which the separation of oxygen from air and the partial oxidation of methane are integrated in one process. At 875℃, 94% of methane conversion, 98% of CO selectivity, 95% of H2 selectivity, and as high as 8.8 mL/(min · cm2) of oxygen flux were obtained. In POM reaction condition, the membrane tube shows a very good stability. 相似文献
82.
针对有限元和试验模态分析的局发性,探讨了一种有限元分析与动态试验相结合的模型修正方法,即基于LINK的结构系统建模方法。将计算与试验结果进行数据融合,以给定模态置信度准则为基础,进行模型的迭代修正分析,进而构造精确的结构系统动力模型,最后基于LINK方法,对梁结构进行了计算与试验相结合的建模分析,取得了良好的效果。 相似文献
83.
龚家骧 《福建师范大学学报(自然科学版)》1993,9(2):28-32
本文从Cartan联络CΓ、Berwald联络BΓ和Rund联络RΓ所共有的非线性联络G出发,得到了一些不同于G的非线性联络以及这些非线性联络所确定的半对称度量Finsler联络,其中之一是Wagner联络。 相似文献
84.
用抗基因工程人γ-干扰素单克隆抗体(2A12)细胞株亲和层析从表达人γ-干扰素的大肠杆菌抽提液中纯化经稀释复性后的γ-干扰素。一步纯化后的γ-干扰素含量达95%以上,蛋白质的比活性达 1.2×10u/g,收率为78%。洗脱液用 0.5mol/LNaCI的 PBS溶液,洗脱率达92.8%。 相似文献
85.
本文根据四个不同回采参数试采面的钻孔注(放)水试验资料,研究了每个采面底板采动破坏深度和强度,分析了采面斜长、采高与底板采动破坏深度的关系,查明厚煤层分层开采时,底板破坏程度主要取决于第一分层,为改革采煤方法安全带压开采提供了依据。 相似文献
86.
87.
谷氨酸离子交换过程动态穿透曲线的分析 总被引:3,自引:0,他引:3
介绍了一种新的分析离子交换过程穿透曲线的方法,该方法采用特定的函数来描述穿透曲线以求出在不同实验条件下的离子交换过程的传质参数。该特定函数建立在吸附区传质概率的基础上,因此传质机制可以用函数的常数来表示,无需识别传质机理。采用该方法建立了NH4+型阳离子交换树脂吸附谷氨酸的穿透曲线模型,以得到离子交换过程的传质参数。 相似文献
88.
The possible subduction of continental material to depths greater than 200 km 总被引:102,自引:0,他引:102
Determining the depth to which continental lithosphere can be subducted into the mantle at convergent plate boundaries is of importance for understanding the long-term growth of supercontinents as well as the dynamic processes that shape such margins. Recent discoveries of coesite and diamond in regional ultrahigh-pressure (UHP) metamorphic rocks has demonstrated that continental material can be subducted to depths of at least 120 km (ref. 1), and subduction to depths of 150-300 km has been inferred from garnet peridotites in orogenic UHP belts based on several indirect observations. But continental subduction to such depths is difficult to trace directly in natural UHP metamorphic crustal rocks by conventional mineralogical and petrological methods because of extensive late-stage recrystallization and the lack of a suitable pressure indicator. It has been predicted from experimental work, however, that solid-state dissolution of pyroxene should occur in garnet at depths greater than 150 km (refs 6-8). Here we report the observation of high concentrations of clinopyroxene, rutile and apatite exsolutions in garnet within eclogites from Yangkou in the Sulu UHP metamorphic belt, China. We interpret these data as resulting from the high-pressure formation of pyroxene solid solutions in subducted continental material. Appropriate conditions for the Na2O concentrations and octahedral silicon observed in these samples are met at depths greater than 200 km. 相似文献
89.
当前工程实践教学改革的误区及对策 总被引:4,自引:0,他引:4
当前工程实践教学存在着人才培养目标定位不明确、重内容改革轻师资建设、重经费投入轻资源共享等若干误区,而产生误区的根源在于缺乏对实践教学及其改革的系统认识.因此,结合系统特性,采取科学定位人才培养目标、大力加强实践教学师资队伍建设以及不断推进实践教学资源共享等有效措施,确保取得成效. 相似文献
90.
Elemental composition of aerosols collected in the glacier area on Nyainqêntanglha Range, Tibetan Plateau, during summer monsoon season 总被引:1,自引:0,他引:1
In order to investigate the elemental composition in atmospheric aerosols and its sources in the glacier area over the Tibetan Plateau (TP), seven totally suspended particle samples were collected continuously at the col of the Zhadang glacier (30°28′N,90°39′E,5800 m a.s.l.), Nyainqêntanglha Range, southern TP, from June to October 2006. Twenty-seven elements (Li, Be, B, Na, Mg, Al, K, Ca, Sc, Ti, V, Fe, Mn, Zn, Ga, As, Rb, Sr, Y, Cd, Cs, Ba, Tl, Pb, Bi, Th, U) were analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The result indicates that the concentrations of most elements (especially crustal elements) are lower than values at the Nam Co Station during the same period of 2005, and also much lower than other sites in the TP such as Wudaoliang and Waliguan. This suggests that elemental compositions of aerosols in the Zhadang glacier area may represent the background levels of the middle/upper troposphere over the TP. Crustal enrichment factors (EFs) reveal that several elements (e.g. B, Zn, As, Cd, Pb and Bi) may have anthropogenic sources. The southern TP is mainly influenced by the summer Indian monsoon during the sampling period. Backward air mass trajectory analysis suggests that air masses in the region may originate from South Asia. Therefore, anthropogenic pollutants from South Asia may be transported by the summer Indian monsoon to the region which clearly affects the atmospheric environment in the southern TP during the summer monsoon season. 相似文献