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991.
Peng Xue Ting He Huiqiong Wu Hongtao Xie Rujuan Shen Fan Yue 《Supramolecular chemistry》2017,29(8):627-632
A tripeptide (β-AspFF) gelator was designed and synthesised using solid-phase peptide synthesis. The as-prepared gelator formed a stable and clear multi-responsive gel in toluene solution. Encapsulating the quantum dots with β-AspFF effectively increased stability and antioxidisation ability which are beneficial for optical identification. 相似文献
992.
993.
994.
A series of (3-oxo-1,3-diaryl) propylpropanedinitriles were synthesized by Michael addition reaction of chalcones and malononitriles in the presence of potassium fluoride on alumina. 相似文献
995.
A. Yan X. Chen R. Zhang M. Liu Z. Hu B. T. Fan 《SAR and QSAR in environmental research》2013,24(3-4):235-244
Abstract Artificial Neural Networks (ANNs) with Extended Delta-Bar-Delta (EDBD) back propagation learning algorithm have been developed to predict the standard enthalpy and entropy of 87 acyclic alkanes. Molecular weight, boiling point and density of the compounds were used as input parameters. The network's architecture and parameters were optimized to give maximum performances. The best network was a 3-6-2 ANN, and the optimum learning epoch was about 1320. The results show that the maximum relative errors of enthalpy and entropy are less than 3%. They reveal that the performances of ANNs for predicting the enthalpy and entropy of alkanes are satisfying. 相似文献
996.
997.
Liuhua ChenLihua Gan Mingxian LiuRong Fan Zijie XuZhixian Hao Longwu Chen 《Applied Surface Science》2011,257(11):5070-5076
The effect of tryptophan on the membrane stability was studied by using three artificial biological membranes including liposome, Langmuir monolayer and solid supported bilayer lipid membrane (s-BLM) as models. All the results indicate that the penetration of tryptophan can destabilize different artificial biological membranes. The diameter of liposome and the leakage of calcein from liposome increased with the increase of tryptophan concentration because the penetration of tryptophan was beneficial for dehydrating the polar head groups of lipids and the formation of fusion intermediates. π-A isotherms of lecithin on the subphase of tryptophan solution further confirm that tryptophan can penetrate into lipid monolayer and reduce the stability of lipid monolayer. When the concentration of tryptophan increased from 0 to 2 × 10−3 mol L−1, the limiting molecular area of lecithin increased from 110.5 to 138.5 Å2, but the collapse pressure of the monolayer decreased from 47.6 to 42.3 mN m−1, indicating the destabilization of lipid monolayer caused by the penetration of tryptophan. The resistance spectra of s-BLM demonstrate that the existence of tryptophan leads to the formation of some defects in s-BLM and the destabilization of s-BLM. The values of electron-transfer resistance and double layer capacitance respectively decreased from 5.765 × 106 Ω and 3.573 × 10−8 F to 1.391 × 106 Ω and 3.340 × 10−8 F when the concentration of tryptophan increased from 0 to 2 × 10−3 mol L−1. Correspondingly, the breakdown voltage of s-BLM decreased from 2.51 to 1.72 V. 相似文献
998.
Previously the perihelion advance in binary system was computed approximately. We will present an exact analytical solution
to nonlinear differential equation of perihelion advance by method of Jacobian elliptic function and the advanced angle between
successive perihelions.
Project supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars from Ministry of Education,
China (Grant No. [2004]527) and the Natural Science Foundation of Hunan Province, China (Grant No. 06JJ2026) 相似文献
999.
<正>A novel caged-prenylxanthone xanthone,neobractatin(1),was isolated from the twig of Garcinia bracteata.Its structure was elucidated by spectroscopic methods,especially 2D NMR techniques. 相似文献
1000.
Chen Peng Liang Xiaoping Wang Jun Zhang Di Yang Shanmin Wu Weishan Zhang Wei Fan Xiaowei Zhang Dequan 《Journal of Sol-Gel Science and Technology》2017,81(3):850-858
Journal of Sol-Gel Science and Technology - To develop high performance mixed matrix gel polymer electrolyte, the synergistic effect of blending PVDF (PEO/PVDF weigh ratio of 85:15) and adding... 相似文献