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我们曾报道CO_2/H_2在CuO-ZnO及CuO-ZnO-ZrO_2催化剂上低压合成甲醇的反应,指出CuO-ZnO-ZrO_2对CO_2/H_2制甲醇具有较高的活性和选择性。本文通过TPD-MS测试研究了第3组分ZrO_2的加入对CO_2/H_2在CuO-ZnO-ZrO_2催化剂上低压合成甲醇的促进作用。 1 实验部分 催化剂的评价在恒压流动反应系统内进行。用色谱仪分析产物(Porapak Q柱,4 mm×3m,柱温120℃,CO、CO_2、CH_3OH、H_2O的保留时间分别为0.55、0.84、4.72、6.6 min),热 相似文献
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A three-dimensional pharmacophore model was developed from a series of inhibitors of Aurora A kinase to discover new potent anti-cancer agents using the HypoGen module in the Catalyst software. The pharmacophore model was developed based on the structure of 20 currently available inhibitors, which were carefully selected from the literature. The best hypothesis (Hypo 1) was defined by four features: one hydrogen-bond donor and three hy- drophobic points, with the best correlation coefficient of 0.909, the lowest rms deviation of 1.563, and the highest cost difference of 99.075. The Hypo 1 was then validated by a test set consisting of 24 compounds and by a cross-validation of 95% confidence level through randomizing the data using the CatScramble program, which suggested that a predictive pharmacophore model had been successfully obtained. 相似文献
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Yongcheng Liu Xin Chen Jianghong Qian Haiying Liu Zhengzhong Shao Jiaqi Deng Tongyin Yu 《Applied biochemistry and biotechnology》1997,62(2-3):105-117
The structure and properties of the blend of regenerated silk fibroin (RSF) and poly(vinyl alcohol) (PVA) were investigated.
The two polymers in the blend are in the state of phase segregation. Infrared (IR) spectra indicate that the RSF in the blend
maintains its intrinsic properties, thus, ethanol treatment can transfer silk I structure of RSF to silk II structure. The
water absorption property and mechanical property of the blend are improved in comparison with those of RSF. The blend maintains
the major merit of RSF, that is, it can immobilize glucose oxidase on the basis of the conformational transition from silk
I structure to silk II structure. The properties of the immobilized enzyme are examined. Moreover, the second generation of
glucose sensor based on the immobilized enzyme is fabricated and it has a variety of advantages including easy maintenance
of enzyme, simplicity of construction, fast response time and high stability. 相似文献
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Two kinds of thio-heterocyclic fused naphthalene carboxamides, 3a-b, 4a-b, were designed, synthesized and quantitatively evaluated as efficient antitumor and DNA photocleaving agents. Compound 3a or 3b, having the thiophene ring, intercalated into DNA more strongly than compound 4a or 4b, having the thioxanthene ring. Compound 4a or 4b, photocleaved DNA more efficiently than 3a or 3b via superoxide anion. Compound 4a was the strongest inhibitor for P388 (murine leukemia cell), while 3a was the most cytotoxic one against A549 (human lung cancer cell). Each new compound showed stronger DNA photocleaving activity than corresponding naphthalimide. 相似文献
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本文报道新的Tweezer(1)的合成,用^1HNMR研究了新的Tweezer分子和对硝基苯甲酸盐的配位效应,结果表明它兴通过氢键,静电引力和芳环夹心堆叠作用而自动缔合。 相似文献