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61.
采用中石化金陵分公司研究院研制的CI-50(Pd/丝光沸石)作C5/C6烷烃异构化催化剂.详细介绍了该催化剂的工业放大试验装置的工艺流程、首次开工过程中技术问题及处理方法.  相似文献   
62.
K0.9Li0.1(Ta0.5Nb0.5)O3晶体压电应变系数的测量   总被引:4,自引:2,他引:2  
用准静态d_(33)测量仪和干涉法相结合。测量了K_(0.9)Li_(0.1)(Ta_(0.5)Nb_(0.5)Nb_(0.5))O_3晶体的压电应变系数。结果为:d_(33)=86.0,d_(33)=一29.5,d_(15)=112.9×10 ̄(-12)C/N.  相似文献   
63.
本文详细研究0.532μm激光泵浦、温度调谐Ⅱ型非临界相位匹配LBO光参量振荡器。当温度从20℃升高到200℃时,其信号波和闲置波的调谐范围分别为1.002~0.898μm和1.134~1.306μm。本装置最吸引人之处是本征输出线宽比Ⅰ型情形小一个量级。  相似文献   
64.
开发了一种静态水热脱铝的方法。HZSM-5经此法处理后,正戊烷的裂解活性增加,脱氢和芳构化性能加强。可用改变处理温度的方法来控制脱铝的程度。用XRD和吡啶吸附红外技术进行了研究。HZSM-5分子筛催化剂性能的变化用非骨架铝产生的强L酸中心来解释。  相似文献   
65.
研究了非晶Sm5Fe74.3Nb1.5Si11.7B4.5C2.5Cu0.5合金经400℃,保温10min预退火后的晶化动力学。结果表明;该合金的晶化相为α-Fe固溶体和Sm2Fe17Cx金属间化合物,两相的晶化表观激活能分别为557KJ/mol和514KJ/mol,当晶化体积分数为60%时,α-Fe相的晶化激活能达极大值;Sm2Fe17Cx相晶化激活能则随其晶化体积分数的增加而逐渐减小。  相似文献   
66.
Reports an error in "Does reward increase or decrease creativity" by Robert Eisenberger and Michael Selbst (Journal of Personality and Social Psychology, 1994[Jun], Vol 66[6], 1116-1127). In the aforementioned article, Figures 1 and 2 were interchanged. The figures appear with their correct captions in the erratum. (The following abstract of the original article appeared in record 1994-40652-001.) Two studies involving 504 school children investigated why behaviorists and cognitively oriented investigators have come to opposite conclusions about reward's effects on creativity. A monetary reward for a high degree of divergent thought in 1 task (word construction) increased children's subsequent originality in a different task (picture drawing). The same reward, made contingent on a low degree of divergent thought, reduced this generalized originality. These effects were eliminated by using a large reward and were restored by keeping the large reward out of the children's sight. The results suggest that reward training increases generalized creativity when (1) a high degree of divergent thought is required and (2) the reward is presented in not too salient a fashion. The findings are consistent with a 2-factor interpretation of rewarded creativity effects that incorporates learned industriousness and selective attention. [A correction concerning this article appears in Journal of Personality & Social Psychology, 1994(Jul), Vol 67(1), 125. Figures 1 and 2 were interchanged.] (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
67.
Silicoaluminophosphate (SAPO-5) molecular sieves have been synthesised from reaction mixtures having a molar composition of: 0.7–1.0 Al2O3:0.7–1.0 P2O5:0.01–2.0 SiO2:xR:40 H2O (where R = (C2H3)3N or (C2H3)4NOH and x = 1.5–2.5 for (C2H5)5N and 0.5 for (C2H5)4NOH, at 473 K using various sources of alumina and silica. The effects of (i) varying the crystallinity of the alumina source (boehmite) and (ii) the use of different silica sources such as freshly prepared silica either from sodium silicate or paddy husk extract, silica gel from commercial water-glass, and tetraethyl orthosilicate have been studied. The crystallinity of boehmite has been found to have a strong effect on its reactivity towards the formation of SAPO-5. The activity of boehmite for SAPO-5 formation increased with a decrease in its crystallinity (or with increase in its moisture content). Any silica source devoid of sodium ions could be employed for the synthesis of SAPO-5. The process of crystallisation started as early as within 1.5 h of reaction and incorporation of silicon into the AlPO4 framework has been noted at this stage. Formation of some tridymite phase as impurity has been observed under conditions such as (i) SiO2 concentration > 1.7 mole and (ii) x > 2.0 when R = (C2H5)3N.  相似文献   
68.
We have localized gene MSS51 on chromosome XII of Saccharomyces cerevisiae between the RDN1 and CDC42 loci. 'Head to head' with MSS51 is another gene, QRI5, the function of which is unknown. However, the proximity of these genes, the structure of the intergenic region and the presence of an ABF1 binding site right in the middle of this region suggest that the MSS51 and QRI5 expressions are submitted to a common regulatory process.  相似文献   
69.
Recombinant cytochrome b5 was extracted into the reversed micelle phase of an anionic surfactant (AOT) in octane and back-extracted to a final aqueous phase. The extraction of the protein was controlled by an electrostatic mechanism, since it was dependent on the global charge of the protein. This was directly demonstrated by experiments with native and mutant cytochromes obtained by site directed mutagenesis. The back-extraction of cytochrome b5 to a fresh aqueous phase was decreased by factors that reduced the size of the water pool of the organic phase, such as high salt concentrations (1–2 mol dm?3 NaCl) and low temperatures (4°C), probably because of an increase in a favourable interaction of this protein with the surfactant at closer distances.  相似文献   
70.
张伟宁  李静  刘军 《宁夏工程技术》2002,1(3):216-217,220
从理论和实践应用方面,研究了在不同活性金属离子存在的条件下控制pH值,应用分步沉积的方法去除Nb(OH)5/Ta(OH)5中某些金属杂质。在一定温度下,可在不影响Nb(OH)5/Ta(OH)5沉积的条件下,达到有效去除Ti,Sb,Sn,Al,Fe等杂质元素的目的。  相似文献   
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