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991.
Shutao Wang Kan Liu Jian Liu Zeta T.‐F. Yu Xiaowen Xu Libo Zhao Tom Lee Eun Kyung Lee Jean Reiss Yi‐Kuen Lee Leland W. K. Chung Jiaoti Huang Matthew Rettig David Seligson Kumaran N. Duraiswamy Clifton K.‐F. Shen Hsian‐Rong Tseng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2011,123(13):2909-2909
992.
利用锥上不动点定理讨论了二阶常微分方程组多点边值问题正解的存在性,所得结论推广了最近的一些结果. 相似文献
993.
994.
995.
Xiao-Jun Yang Feng Gao J. A. Tenreiro Machado Dumitru Baleanu 《The European physical journal. Special topics》2017,226(16-18):3567-3575
In this paper, a new fractional derivative involving the normalized sinc function without singular kernel is proposed. The Laplace transform is used to find the analytical solution of the anomalous heat-diffusion problems. The comparative results between classical and fractional-order operators are presented. The results are significant in the analysis of one-dimensional anomalous heat-transfer problems. 相似文献
996.
997.
Weiwei Gao Shiyong Ye Mingwang Shao 《Journal of Physics and Chemistry of Solids》2011,72(9):1027-1031
Manganese oxide (Mn3O4) nanoparticles with average diameter of 15 nm were prepared using alcohol solution of manganese chloride as starting material via a facile solution-combusting method. The flame core zone was chosen to prepare mono-dispersed and high crystalline products, which were employed to modify glassy carbon electrode and detect dopamine via cyclic voltammetry. The results exhibited excellent electrochemical sensitivity. A linear relationship between the concentration of dopamine and its oxidation peak current was obtained by differential pulse voltammetry, which will find wide application in the biological detection. 相似文献
998.
999.
Jie Ju Yu Jin Li Jian Rong Gao Jian Hong Jia Liang Han Wei Jian Sheng Yi Xia Jia 《中国化学快报》2011,22(4):382-384
An aqueous solution of hydrogen peroxide and hydrogen bromide illuminated by a 60 W incandescent light bulb serves as a source of bromine radicals.Various substituted toluenes(NO2,Cl,Br,H,CH3) were high selectively brominated at the benzyl position for monobromination in CH2C12 at ice water with catalyst free.This simple but effective bromination of toluene derivatives with an aqueous H2O2-HBr system is characterized with the use of inexpensive reagents and a lower impact on the environment, which make it a good alternative to the existing bromination methods. 相似文献
1000.
A novel approach to the synthesis of 4-phenylethynylphthalic anhydride has been described.The target compound was synthesized by Pd/Cu catalyzed Sonogashira coupling reaction between phenylacetylene and 4-bromophthalic acid which was for the first time employed as start material,followed by dehydration of 4-phenylethynylphthalic acid.Compared with traditional synthetic routes,this method provides several advantages such as readily available raw materials,convenient manipulation and high yield.The product... 相似文献