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101.
Kyung Hoi Cha Tae Won Kang Hong-Woo Lee Eung-Nam Kim Nam-Hee Choi Jung-Woo Kim 《合成通讯》2013,43(12):2131-2136
Triphenylphosphine (TPP)-iodotrimethylsilane (TMSI) was found to be a convenient and highly effective catalyst for the tetrahydropyranylation of aliphatic and aromatic alcohols with dihydropyran in dichloromethane at ambient temperature. 相似文献
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Ramazani A. Sheikhi M. Hanifehpour Y. Asiabi P. A. Joo S. W. 《Journal of Structural Chemistry》2018,59(3):529-540
Journal of Structural Chemistry - N-isocyaniminotriphenylphosphorane (Ph3PNNC) is a type of iminophosphorane which is an important reagent in synthetic organic chemistry and a ligand in metallic... 相似文献
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Chang Hyeong Lee Kyung Duk Park Bongsoo Jang 《Journal of mathematical chemistry》2013,51(7):1945-1960
In this paper, we present the multistage homotopy perturbation method for finding the solution of the chemical kinetics with nonlinear reactions. We develop a general scheme for finding the analytic solution of chemical reaction networks and apply it to motivating chemical examples such as the enzyme kinetics model and the Brusselator model. We illustrate the numerical result for the models and show the accuracy of the method. 相似文献
107.
Eun Joo Park Jeongwoo Lee Dongsoo Jung 《Journal of Dispersion Science and Technology》2013,34(10):1485-1492
In order to achieve the dispersion stability of multi-walled carbon nanotubes (MWCNT) in a fluorinated refrigerant (FC-72) used in various cooling purposes, fluorinated MWCNT (MWCNT-F) was prepared by a combined process of oxidation and fluorination. As a fluorine source, (tridecafluoro-1,1,2,2-tetrahydrooctyl)trichlorosilane was used to react with hydroxyl groups on MWCNT (MWCNT-OH) generated by chemical oxidation. Pristine MWCNT, MWCNT-OH, and MWCNT-F were dispersed in FC-72 and MWCNT-F was also dispersed in polar and nonpolar solvents. The MWCNT-F has excellent colloidal stability in FC-72 because of the chemical affinity between FC-72 and functional groups (-CFn) on the side walls of MWCNT. Through surface modifications, we could obtain the enhanced dispersion stability of MWCNT in a refrigerant. This homogenous MWCNT solution in FC-72 may be used to increase the heat transfer in FC-72 based nanofluids. 相似文献
108.
Dr. Todor Baramov Bianca Schmid Ho Ryu Jinhoon Jeong Dr. Karlijn Keijzer Dr. Leonard von Eckardstein Prof. Dr. Mu-Hyun Baik Prof. Dr. Roderich D. Süssmuth 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(28):6955-6962
The E. coli siderophore enterobactin, the strongest FeIII chelator known to date, forms hexacoordinate complexes with SiIV, GeIV, and TiIV. Synthetic protocols have been developed to prepare non-symmetric enterobactin analogues with varying denticities. Various benzoic acid residues were coupled to the macrocyclic lactone to afford a diverse library of ligands. These enterobactin analogues were bound to SiIV, GeIV, and TiIV, and the complexes were investigated through experimental and computational techniques. The binding behavior of the synthesized chelators enabled assessment of the contribution of each of the phenolic hydroxy groups in enterobactin to metal-ion complexation. It was found that at least four O-donors are needed for enterobactin derivatives to act as metal binders. Density functional theory calculations indicate that the strong binding behavior of enterobactin can be ascribed to a diminished translational entropy penalty, a common feature of the chelate effect, coupled with the structural arrangement of the three catechol moieties, which allows the triseryl base to be installed without distorting the preferred local metal-binding geometry of the catecholate ligands. 相似文献
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Ye Linglong Li Xueshan Cai Yunhao Ryu Hwa Sook Lu Guangkai Wei Donghui Sun Xiaobo Woo Han Young Tan Songting Sun Yanming 《中国科学:化学(英文版)》2020,63(4):483-489
Benzo[1,2-b:4,5-b′]dithiophene(BDT) has been widely used to construct donor-acceptor(D-A) copolymers in organic solar cells(OSCs). However, benzo[1,2-b:4,5-b′]difuran(BDF), an analogue of BDT, has received less attention than BDT. The photovoltaic performance of BDF copolymers has lagged behind that of BDT copolymers. Here, we designed and synthesized two BDF copolymers, PBF1-C and PBF1-C-2Cl. PBF1-C-2Cl, which is composed of BDF and benzo[1,2-c:4,5-c′]dithiophene-4,8-dione connected by a chlorinated thiophene π-bridge, displays a low-lying highest occupied molecular orbital energy level,which helps in yielding a high open-circuit voltage(V_(oc)) in OSCs. As a result, when blended with Y6, PBF1-C-2Cl-based devices showed a high V_(oc) of 0.83 V and a power conversion efficiency(PCE) of 13.10%. To the best of our knowledge, the PCE of 13.10% is among the highest efficiency values for OSCs based on BDF copolymers. 相似文献