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71.
72.
Keyu Jiang Qin Fan Tong Chen Changxi Miao Zhenji Zhao Xielong Yang 《Hyperfine Interactions》2012,205(1-3):81-85
Two series of Fe-K catalysts for dehydrogenation of ethylbenzene to styrene were prepared with different amounts and different compounds of the additional element Ce. M?ssbauer spectroscopy has been used to determine the Fe compound in the catalyst and to investigate the effect of Ce. The catalytic properties of the catalysts have also been measured. The results show that the element Ce in the catalyst is favorable to form the predecessor of the catalytic active phase, the compound KFe11O17 and that the optimal percentage of CeO2 is 8%~15% in the catalyst which is favorable to the formation of KFe11O17 and to get better catalytic properties. 相似文献
73.
Chang Ling Zhao Zhong Jian Chen Xue Song Bai Can Ding Ting Ju Long Fu Gang Wei Kang Ru Miao 《Molecular diversity》2014,18(3):687-700
This paper summarizes the main achievements about the structure–activity relationships of anthocyanidin glycosylation. Anthocyanidin glycosylation is the essential step of anthocyanin biosynthesis and also the prerequisite of the further modifications of anthocyanins, which is jointly characterized by the glycosylation site, the type and number of the glycosyl as well as the glycosidic bond type. It generally enhances the stability, results in the hypsochromic effect and blueing, decreases the bioavailability and anticancer activity, and decreases, increases, or does not change the antioxidant activity of the anthocyanidins or anthocyanins, which is synergetically determined by the glycosylation site and the type and number of the glycosyl. Thereinto, in nature, the blue hues caused by the glycosylation may also be reinforced by the formation of the anthocyanic vacuolar inclusions. This review could provide a reference for the research of the structure-optimizing and function-exploiting of anthocyanins. 相似文献
74.
目的 探讨钙蛋白酶-10 基因(CAPN-10)单核苷酸多态性-19(SNP-19)与多囊卵巢综合征(PCOS)的相关性。
方法 采用聚合酶链反应- 限制性片段长度多态性(PCR-RFLP)技术,对107 例PCOS患者(PCOS 组)及111 例健康体检者(对照组)的CAPN-10 SNP-19 进行分析,并测定其性激素和生化指标。PCOS组再根据BMI与胰岛素抵抗(IR)稳态模型指数(HOMA-IR)分为肥胖组与非肥胖组、IR 组与非IR 组,分析CAPN-10 SNP-19 与其关系。结果 与对照组相比,PCOS 组BMI、空腹血糖(FPG)、TG、TC、LDL、黄体生成素(LH)、黄体生成素/ 卵泡刺激素(LH/FSH)、睾酮(T)均升高(均P<0.01)。PCOS 组CAPN-10 SNP-19 1等位基因及1/2基因型频率均高于对照组(均P<0.05);且CAPN-10 SNP-19 1/2基因型PCOS 发病风险较1/1、2/2 基因型增加约2倍(OR=1.9,95%CI=1.1~3.3,P<0.05)。CAPN-10 SNP-19 1、2等位基因频率PCOS 肥胖组与非肥胖组、IR 组与非IR组比较均无统
计学差异(均P>0.05);PCOS 肥胖组和IR组CAPN-10 SNP-19 1/2基因型频率分别高于非肥胖组和非IR 组,但差异均无统计学意义(均P>0.05)。结论 CAPN-10 SNP-19 与PCOS 遗传易感性有关,可能与PCOS 肥胖及IR 无关。 相似文献
75.
Yu-Gui Li Yun-Shan Liu Fang-Ming Miao Xiao-Lan Liu Jin-Hong Cao Wei Zhou 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):57-60
Abstract Twenty-three new α -aryl-β -nitroalkylphosphinates 3a - g were synthesized in high yields under very mild conditions. Compounds 3 consist of two pairs of diastereomeric isomers (A) and (B) 相似文献
76.
77.
Yongqiang Zhang ShengzhengWang Zhenyuan Miao Jianzhong Yao Wannian Zhang Chunquan Sheng 《中国化学》2013,(9):1139-1143
Iodiconazole is a novel antifungal agent that was developed in its racemic form. In order to investigate the ef- fects of the chiral center on the antifungal activity, R- and S-isomers of iodiconazole were prepared on the basis of the asymmetric Sharpless epoxidation. (S)-Iodiconazole was proved to have better antifungal activity than the (R)- isomer. The binding modes of the two isomers with lanosterol 14~z-demethylase were clarified by molecular dock- ing. 相似文献
78.
Xiuquan Jia Jiping Ma Penghua Che Fang Lu Hong Miao Jin Gao Jie Xu 《Journal of Energy Chemistry》2013,22(1):93-97
Direct conversion of fructose-based carbohydrates to 5-ethoxymethylfurfural (EMF) catalyzed by Lewis acid in ethanol was investigated. It was found that BF3·(Et)2O was favorable for 5-hydroxymethylfurfural (HMF) etherification to EMF. BF3·(Et)2O combination with AlCl3·6H2O with the molar ratio of 1 was an effective catalyst system for synthesis of EMF from fructose-based carbohydrates. 55.0%, 45.4% and 23.9% of EMF yields were obtained from fructose, inulin and sucrose under optimized conditions, respectively. 相似文献
79.
Bai‐Zhan Liu Li Yao Sai‐Jing Zheng Wei‐Miao Wang Xiao‐Lan Zhu Jun Yang 《中国化学会会志》2013,60(8):1055-1061
An efficient and sensitive analytical method based on molecularly imprinted solid‐phase extraction (MISPE) and reverse‐phase ultrasound‐assisted dispersive liquid–liquid microextraction (USA‐DLLME) coupled with LC–MS/MS detection was developed and validated for the analysis of urinary 4‐(methylnitrosamino)‐1‐(3‐pyridyl)‐1‐butanol (NNAL), a tobacco‐specific nitrosamine metabolite. The extraction performances of NNAL on three different solid‐phase extraction (SPE) sorbents including the hydrophilic‐lipophilic balanced sorbent HLB, the mixed mode cationic MCX sorbent and the molecularly imprinted polymers (MIP) sorbent were evaluated. Experimental results showed that the analyte was well retained with the highest extraction recovery and the optimum purification effect on MIP. Under the optimized conditions of MIP and USA‐DLLME, an enrichment factor of 23 was obtained. Good linearity relationship was obtained in the range of 5‐1200 pg/mL with a correlation coefficient of 0.9953. The limit of detection (LOD) was 0.35 pg/mL. The recoveries at three spiked levels ranged between 88.5% and 93.7%. Intra‐ and inter‐day relative standard deviations varied from 3.6% to 7.4% and from 5.4% to 9.7%, respectively. The developed method combing the advantages of MISPE and DLLME significantly improves the purification and enrichment of the analyte and can be used as an effective approach for the determination of ultra‐trace NNAL in complex biological matrices. 相似文献
80.
Yu Liu Lei Zhao Wentao Li Dongyu Zhao Miao Song Yongliang Yang 《Journal of computational chemistry》2013,34(1):67-75
The accurate prediction of protein–ligand binding is of great importance for rational drug design. We present herein a novel docking algorithm called as FIPSDock, which implements a variant of the Fully Informed Particle Swarm (FIPS) optimization method and adopts the newly developed energy function of AutoDock 4.20 suite for solving flexible protein–ligand docking problems. The search ability and docking accuracy of FIPSDock were first evaluated by multiple cognate docking experiments. In a benchmarking test for 77 protein/ligand complex structures derived from GOLD benchmark set, FIPSDock has obtained a successful predicting rate of 93.5% and outperformed a few docking programs including particle swarm optimization (PSO)@AutoDock, SODOCK, AutoDock, DOCK, Glide, GOLD, FlexX, Surflex, and MolDock. More importantly, FIPSDock was evaluated against PSO@AutoDock, SODOCK, and AutoDock 4.20 suite by cross‐docking experiments of 74 protein–ligand complexes among eight protein targets (CDK2, ESR1, F2, MAPK14, MMP8, MMP13, PDE4B, and PDE5A) derived from Sutherland‐crossdock‐set. Remarkably, FIPSDock is superior to PSO@AutoDock, SODOCK, and AutoDock in seven out of eight cross‐docking experiments. The results reveal that FIPS algorithm might be more suitable than the conventional genetic algorithm‐based algorithms in dealing with highly flexible docking problems. © 2012 Wiley Periodicals, Inc. 相似文献