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81.
C. V. Yelamaggad S. Anitha Nagamani U. S. Hiremath D. S. Shankar Rao S. Krishna Prasad 《Liquid crystals》2013,40(2):231-236
The molecular design, synthesis and thermal behaviour of the first liquid crystalline tetramers composed of four non-identical mesogenic entities connected covalently through paraffinic spacers are presented. These new molecular structures consisting of a tolan (half disc-shaped), azobenzene (photoactive), biphenyl and cholesteryl ester (thermochromic) cores, connected through either an even-even-odd or an odd-even-odd paraffinic spacer, exhibit features of a columnar mesophase. 相似文献
82.
An efficient and highly stereocontrolled convergent synthesis of fluvirucinine A1 is reported herein. In fluvirucinine A1 both C5-C13 and C1-C4 fragments were accessed from a common intermediate 6 derived from (S)-Roche ester in 15 and 7 steps, respectively. The key steps involve Evans asymmetric alkylation, Sharpless asymmetric epoxidation, amidation and a ring-closing metathesis reaction (RCM) for macrocyclization. 相似文献
83.
本文通过计算分析和理论证明,提出从光源出光功率分布和传播介质两方面抑制细光束发散或衍射的途经,原理实验证明这些途径是可行的,可以充分满足实际使用要求。 相似文献
84.
本文从理论上证明,由于各种表面效应和光在焦点处的特殊性质及径向梯度介质的本征非线性作用,凡经聚焦而进入径向梯度介质的细光束,均会产生稳态半自陷而保径传播。这为开辟该介质的应用提供了新的理论根据。 相似文献
85.
86.
P Keerthana Abbo Hanna Cherian Anila Rose Titinchi Salam Varghese Anitha 《Journal of fluorescence》2022,32(3):1109-1124
Journal of Fluorescence - The formation of an inclusion complex between hydroxypropyl-β-cyclodextrin (H-CD) and 4-acetylphenyl-4-(((6-chlorobenzo[d]thiazol-2-yl)-imino)-methyl)-benzoate (L)... 相似文献
87.
Basavaraju Srinivas Kannekanti Lalitha Police Anil Kumar Reddy Gajeelli Rajesh Valluri Durga Kumari Machiraju Subrahmanyam Bhudev Ranjan De 《Research on Chemical Intermediates》2011,37(8):1069-1086
Abstract
The liquid-phase selective dehydrogenation of cyclohexanol has been investigated using two classes of catalyst containing either Cu2O or CuO on TiO2 under solar light in deaerated conditions at room temperature using acetonitrile medium in a batch reactor. The effect on dehydrogenation of three conditions, cyclohexanol concentration, copper loading on TiO2, and amount of catalyst, were investigated. The maximum yield of cyclohexanone obtained was 40%. The catalysts were characterized by XRD, UV–DRS, TEM, SEM–EDAX, and XPS. It was found that 1% (w/w) Cu2O/TiO2 was 100% selective for photocatalytic dehydrogenation of cyclohexanol. 相似文献88.
89.
Srinivas Gangula Chandrashekhar R. Elati Satish Varma Mudunuru Anitha Nardela Ashok Dongamanti Apurba Bhattacharya 《合成通讯》2013,43(15):2254-2268
Syntheses of all eight enantiomerically pure diastereomers of aprepitant and assignment of absolute configuration at newly generated stereocenters by NMR and x-ray crystallographic analysis were achieved. 相似文献
90.
WU Yi TENG Guo-sheng LIANG Yong-tao ZHONG Da-fang LIU Bing . College of Pharmacy Jilin University Changchun P. R. China . College of Life Science Changchun . School of Chemistry Life Science Changchun University of Technology . Jilin Provincial Corps Hospital Chinese People''s Armed Police Forces Changchun 《高等学校化学研究》2009,25(5):673-676
A simple, rapid and sensitive method for the determination of protopanaxadiol in rat plasma with ginse-noside Rh2 as internal standard was developed and validated. The analyte and internal standard were extracted from plasma with ether-dichloromethane(3:2, volume ratio) and then were analyzed by reversed-phase HPLC on a short Zorbax Extend C18 column(50 mm×2.1 mm, 3.5 μm i. d.) eluted with a mobile phase consisting of acetoni-trile/methanol 0.10 mmol/L ammonium acetate(45:45:10, volume ratio) at 0.4 mL/min.... 相似文献