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931.
Yong Yuan Yangmin Cao Jin Qiao Yueping Lin Xiaomei Jiang Yaqing Weng Shan Tang Aiwen Lei 《中国化学》2019,37(1):49-52
Selective oxidative C—H sulfenylation of imidazopyridine heterocycles is achieved using an undivided electrolytic cell. The reaction avoids the use of stoichiometric amount of external chemical oxidant and produces hydrogen gas as the only byproduct. Both aryl and aliphatic thiols demonstrate good reactivity for C—S bond formation. 相似文献
932.
We embed an approximate dynamic program into a branch-and-bound framework to solve sequential resource allocation problems in population disease management. The proposed algorithm is capable of providing an optimality guarantee and getting bounds on the optimality gap of healthcare interventions. A numerical study on screening and treatment policy implementation for chronic hepatitis C virus (HCV) infection provides useful insights regarding HCV elimination for baby boomers. 相似文献
933.
Min Wen Xijing Wang Prof. Dr. Ting Wang Yan Sun Mengting Fan Min Li Junru Zhu Prof. Dr. Dazhi Zhang Prof. Dr. Xiaoyan Cui Prof. Dr. Yongkui Shan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(15):3247-3251
Acridinium benzoate was developed as a unique ICT-based fluorescent scaffold for both ratiometric and turn-on fluorescence imaging through decaging of the phenolic hydroxyl groups. Two fluorescent probes, Acr1-H2O2 and Acr1- β -gal , were developed for the fluorescence imaging of H2O2 and β-galactosidase in vivo. 相似文献
934.
Two new tetranuclear NiII complexes, [Ni4(L1)2(N3)4(MeOH)2]·CH3COCH3 (1) and [Ni4(L2)2(N3)4(MeOH)2]·4CH3COCH3 (2) , were synthesized using NiCl2·6H2O, NaN3, and asymmetric salamo‐based ligands H2L1 and H2L2, respectively. The structural characterization was made by elemental analyses, infrared (IR) and ultraviolet‐visible (UV‐vis) spectra, and X‐ray diffraction analyses. The results of X‐ray diffraction analyses show that the NiII atoms in complexes 1 and 2 are distorted octahedral geometries. Interestingly, the degree of distortion of the ligands in complexes 1 and 2 is different, which indicates that the interaction of NiII ions on different ligands is different. Meanwhile, the investigation of molecular packing by employing the Hirshfeld surface analysis exhibits that the percentages of C–H/H–C, O–H/H–O, and H–H/H–H contacts of the complex 1 (or 2 ) are calculated to be 17.7%, 7.9%, and 53.7% (or 18.8%, 13.8%, and 52.5%), respectively, where the H–H/H–H contacts have the characteristics of strong contacts whereas the O–H/H–O hydrogen bonds are considerably weak, and the studies on fluorescence properties further confirm the NiII atoms have different binding abilities to the different ligands. 相似文献
935.
Fluid Dynamics - A high-order discontinuous Galerkin method is employed to study the evolution of the flow structure in the gap and near wake of two tandem cylinders in the alternating in the gap... 相似文献
936.
Song Shan Lu Jiaorong Ye Weiyu Zhang Bei Liu Xuan Xing Guichuan Zhang Shiming 《中国科学:化学(英文版)》2021,64(9):1441-1459
Organic photovoltaics(OPVs) have become a timely research topic for their advantages of light weight, low cost, low toxicity,environmental adaptability, flexibility, and large-area manufacture, especially after non-fullerene acceptor ITIC reported in 2015.The highest power conversion efficiency(PCE) is currently above 18% for OPV. However, there are still imparities in the efficiency of OPVs when compared with silicon-based photovoltaics, as well as in their shelf life. Compared with inorganicbased photovoltaics, the efficiency of large-area OPVs is lower and the life time of OPVs is shorter. Therefore, such inferior performance of large-area OPVs restricts the commercial development. Based on these constraints, this paper reviews the research work regarding OPVs into three aspects: stability, encapsulation technology, and recent large-area preparation technologies. 相似文献
937.
Gao Huang Yujia Shan Dr. Jin-Tao Yu Dr. Changduo Pan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(48):12294-12299
A rhodium(III)-catalyzed C6-selective dehydrogenative cross-coupling of 2-pyridones with thiophenes was developed for the synthesis of 6-thiophenyl pyridin-2(1H)-one derivatives. In this reaction, the excellent site selectivity was controlled by the 2-pyridyl directing group on the nitrogen of the pyridone ring. Control experiments indicated that the N-pyridyl was essential for the transformation. To the best of our knowledge, this procedure is the first successful example of the direct C6 heteroarylation of 2-pyridones with electron-rich thiophene derivatives. 4-Pyridone was also used as substrate to generate the corresponding C2 heteroarylated product. Moreover, this pyridyl directing group was readily removable to generate the biheteroaryl structures with a free N−H group. 相似文献
938.
939.
Tri(o-bromobenzyl)tin diethyldithiocarbamate(1) and tri(m-fluorobenzyl)tin pyrrolidine dithiocarbamate(2) have been synthesized and characterized by elemental analysis, IR spectroscopy, NMR(~1 H, 13C and 119Sn), thermogravimetric analysis and single-crystal X-ray diffraction. The two complexes crystallize in the triclinic system space group P1. For complex 1, a = 0.9770(1), b = 1.1011(1), c = 1.4583(1) nm, α = 78.431(1)°, β = 86.307(1)°, γ = 69.712(1)°, V = 1.4417(2) nm^3, Z = 2, Dc = 1.790 g/cm^3, m(Mo Kα) = 52.04 cm–1, F(000) = 756, R = 0.0434 and wR = 0.0593. For complex 2, a = 0.7055(1), b = 1.3349(3), c = 1.3782(3) nm, α = 89.216(2)°, β = 82.044(2)°, γ = 84.637(2)°, V = 1.2799(5) nm^3, Z = 2, Dc = 1.537 g/cm^3, m(Mo Kα) = 11.98 cm–1, F(000) = 596, R = 0.0313 and wR = 0.0333. The two complexes represent mononuclear structures with five-coordinated [SnC3S2] cores forming a distorted trigonal bipyramid. The quantum chemical calculations of 1 and 2 have been investigated. The antitumor activity shows that 1 and 2 have higher activities than cisplatinum against Colo205, HepG2, MCF-7, Hela and H460 cell line in vitro. 相似文献
940.
Zeng Shan Jing Yuan Yuan Chenheng 《Journal of Thermal Analysis and Calorimetry》2021,146(3):1359-1369
Journal of Thermal Analysis and Calorimetry - The free piston linear engine (FPLE) eliminates the crankshaft components and supports variable compression ratio operation. This characteristic makes... 相似文献