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51.
Xinzhi Chen Shaodong Zhou Yuehan Chen Zehan Dong Yeyu Gao Chao Qian Chaohong He 《Research on Chemical Intermediates》2012,38(9):2255-2269
Alcoholate was utilized in catalytic transfer hydrogenation of unsaturated nitrogen compounds. In the reduction of nitro compounds, oximes and imines, alkoxide was used as the promoter, with alcohol as the hydrogen source, while in the reduction of nitriles, alkoxide was used as the hydrogen source. 相似文献
52.
Yue Shao Hong-Ping Zhao Xi-Qiao Feng Huajian Gao 《Journal of the mechanics and physics of solids》2012,60(8):1400-1419
Studying the structure–property relation of biological materials can not only provide insight into the physical mechanisms underlying their superior properties and functions but also benefit the design and fabrication of advanced biomimetic materials. In this paper, we present a microstructure-based fracture mechanics model to investigate the toughening effect due to the crack-bridging mechanism of platelets. Our theoretical analysis demonstrates the crucial contribution of this mechanism to the high toughness of nacre. It is found that the fracture toughness of nacre exhibits distinct dependence on the sizes of platelets, and the optimized ranges for the thickness and length of platelets required to achieve higher fracture toughness are given. In addition, the effects of such factors as the mechanical properties of the organic phase (or interfaces), the effective elastic modulus of nacre, and the stacking pattern of platelets are also examined. Finally, some guidelines for the biomimetic design of novel materials are proposed based on our theoretical analysis. 相似文献
53.
Kai Zhao Yulong Xiao Chunxiang Guo Qing Chang Hongfei Gao Xiaohong Cheng 《Tetrahedron》2019,75(3):409-415
Using Suzuki coupling reactions as key steps, a series of fluorenone-based polycatenars, consisting of a central 2,7-diphenyl-9-fluorenone core connected with the 3,4,5-trialkoxybenzoate unit via –COO- linkage at each side have been synthesized. Upon elongation of the terminal alkyl chain, these compounds self-assembled into mesophase sequence of Colhex/p6mm - CubI/ in solid states as well as organogels with interesting morphologies varied from 3D helical fibers to spherical structures in solvents. 相似文献
54.
Xiao-Yi Song Yu-Hang Zhang Ping-Ping Sun Prof. Dr. Jun Gao Prof. Dr. Fa-Nian Shi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(25):5654-5661
Novel lithium–lanthanide (Ln: cerium and praseodymium) bimetallic coordination polymers with formulas C10H2LnLiO8 (Ln: Ce (CeLipma) and Pr (PrLipma)) and C10H3CeO8 (Cepma) were prepared through a simple hydrothermal method. The three compounds were characterized by means of FTIR spectroscopy, X-ray diffraction, single-crystal X-ray diffraction, SEM, TEM, and X-ray photoelectron spectroscopy. The results of structural refinement show that they belong to triclinic symmetry and P space group with cerium (or praseodymium) and lithium cations, forming coordination bonds to oxygen atoms from different pyromellitic acid molecules, and leading to the construction of 3D structures. It is interesting to note that the frameworks exclude any coordination water and lattice water. As an electrode material for lithium-ion batteries, CeLipma exhibits a maximum capacity of 800.5 mAh g−1 and a retention of 91.4 % after 50 cycles at a current density of 100 mA g−1. The favorable electrochemical properties of the lanthanide coordination polymers show potential application prospects in the field of electrode materials. 相似文献
55.
Xiaoyan Deng Guihong Liao Qingwu Long Yujiao Gao Hao Peng Hongwu He 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):663-671
Abstract A series of [(substituted phenoxyacetoxy)(substituted phenyl)methyl](methyl)phos- phinates containing fluorine were designed and synthesized. All the synthesized compounds were identified by elemental analysis, IR, 1H NMR, mass spectrometry. O-methyl [(2-fluorophenoxyacetoxy)(2,4-dichlorophenyl)methyl](methyl)phosphinate was further analyzed by X-ray single-crystal diffraction. Their herbicidal activity against a set of weed species was examined. Some of the compounds showed potential herbicidal activity, which provided some indications for further studies on structure modification. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
56.
Qi Lin You-Ming Zhang Li-Ming Gao Tai-Bao Wei Hai Wang 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2051-2057
A novel and efficient method for synthesis ethoxycarbonyl isothiocyanate and ethoxycarbonyl thioureas catalyzed by TMEDA is reported. A series of N-aryl-N′-ethoxycarbonyl thioureas and arene (or polymethylene)-bis-ethoxycarbonyl thiourea derivatives have been synthesized in good-to-excellent yields via this method at room temperature. 相似文献
57.
58.
2β,3α-Dihydroxyurs-12-en-28-oic acid(6) is a naturally occurring diastereoisomer of corosolic acid with glycogen phosphorylase inhibitory activity.A new strategy for the semi-synthesis of 6 was developed.Using the commercially available ursolic acid(1) as the starting materials,6 was synthesized through five facile reactions with a high stereoselectivity and an overall yield of 47.3%.The structure of 6 was confirmed by optical rotation.ESI-MS,1H NMR and 13C NMR data. 相似文献
59.
Polymer light-emitting electrochemical cells (PLECs) employ a thin layer of a luminescent conjugated polymer admixed with an ionic source and an ionic conductor for the in-situ formation of p-i-n junction and subsequent efficient injections of both electrons and holes.The junction formation enables the use of air-stable conductors as the cathode and a relatively thick emissive polymer layer that is more compatible with low-cost solution-based processes.This paper overviews the operation mechanism of the PLECs,the properties and drawbacks of the devices.The employment of crosslinkable ionic conductors to stabilize the p-i-n junction is reviewed.The resulting static junction electroluminesces light at high brightness,high efficiency,and prolonged lifetime.Silver paste and carbon nanotubes can be used as the cathode,thus,PLECs were fabricated by lamination.Using single wall carbon nanotubes coated elastic substrate as both anode and cathode,the PLECs can be made highly stretchable. 相似文献
60.
Cuiling Du Dr. Jie Zhao Dr. Jinbo Fei Dr. Liang Gao Wei Cui Dr. Yang Yang Prof. Dr. Junbai Li 《化学:亚洲杂志》2013,8(4):736-742
A reactive template method was used to fabricate alginate‐based hydrogel microcapsules. The uniform and well‐dispersed hydrogel capsules have a high drug loading capacity. After they are coated by a folate‐linked lipid mixture on the surface, the capsules possess higher cell uptake efficiency by the molecule recognition between folate and the folate‐receptor overexpressed by the cancer cells. Moreover, in this bioconjugate, the lipid could remarkably reduce the release rate of hydrophilic doxorubicin from the hydrogel microcapsules and encapsulate the hydrophobic photosensitizer hypocrellin B. The biointerfaced capsules could be used as drug carriers for combined treatment against cancer cell proliferation in vitro; this was much more effective than chemotherapy or photodynamic therapy alone. 相似文献