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991.
992.
Yingfen Li Xian Wei Song Bai Zhi‐Gang Xu Menglan Lv 《Journal of heterocyclic chemistry》2019,56(12):3429-3434
The skeleton of fused benzimidazole‐pyrazine was constructed via an Ugi/deprotection/cyclization (UDC) and hydroamination cascade reaction. This four‐step reaction was carried out in a one‐pot procedure with only one‐time column chromatography purification. The representative compound 7b exhibited 67% cell growth inhibitory activity against human breast cancer cell line MDA‐MB‐453 at the concentration of 10μM. 相似文献
993.
Zhang Hengkai Zhang Yaokang Yang Guang Ren Zhiwei Yu Wei Shen Dong Lee Chun-Shing Zheng Zijian Li Gang 《中国科学:化学(英文版)》2019,62(7):875-882
From a base material of conductive polymer(poly-(3,4-ethylenedioxythiophene):poly(styrenesulfonate),PEDOT:PSS),a flexible and high-conductivity(as low as 45Ω/sq)transparent electrode was fabricated on polydimethylsiloxane elastomer by an acid treatment and transfer process.Combined with the D-sorbitol-doped PEDOT:PSS electric glue,we successfully demonstrated a vacuum-free and ambient lamination fabrication process for semi-transparent perovskite solar cells using triple cation Cs_(0.05)(MA_(0.17)FA_(0.83))_(0.95)Pb(I_(0.83)Br_(0.17))_3perovskite.By this manufacturing-friendly lamination process,we fabricated semitransparent perovskite solar cell devices with power conversion efficiencies up to 16.4%and variable transparencies. 相似文献
994.
Zhong Zhengkun Kan Wentao Liao Wei 《Journal of Radioanalytical and Nuclear Chemistry》2019,319(1):453-458
In order to select a chelator with excellent stability, easier radiolabeling process and low cost, GRPr antagonist RM26 with the amino acid based chelator was radiolabeled with technetium-99m. The stability of the radiolabeled peptides in PBS, serum as well as in the presence of excess cysteine was compared.
相似文献995.
Wang Xia Qian‐Jin An Shao‐Hua Xiang Shaoyu Li Yong‐Bin Wang Bin Tan 《Angewandte Chemie (International ed. in English)》2020,59(17):6775-6779
N‐arylcarbazole structures are important because of their prevalence in natural products and functional OLED materials. C?H amination of arenes has been widely recognized as the most efficient approach to access these structures. Conventional strategies involving transition‐metal catalysts suffer from confined substrate generality and the requirement of exogenous oxidants. Organocatalytic enantioselective C–N chiral axis construction remains elusive. Presented here is the first organocatalytic strategy for the synthesis of novel axially chiral N‐arylcarbazole frameworks by the assembly of azonaphthalenes and carbazoles. This reaction accommodates broad substrate scope and gives atropisomeric N‐arylcarbazoles in good yields with excellent enantiocontrol. This approach not only offers an alternative to metal‐catalyzed C–N cross‐coupling, but also brings about opportunities for the exploitation of structurally diverse N‐aryl atropisomers and OLED materials. 相似文献
996.
Today, the design of new compounds with giant nonlinear optical responses is attracted to many researchers. Inspired by an interesting finding of a new class of heteroborospherenes which were formed by doping four carbon atoms in the B364- nanocluster (C4B32), we suggest the alkali metal-doped C4B32 (M@C4B32, M=Li, Na, and K) nanoclusters as high-performance nonlinear optical materials. Our results show that the alkali metal atoms have a considerable effect on the structural and electronic properties of the C4B32 nanocluster. We found that the doping alkali metal can remarkably decrease the HOMO-LUMO gap and significantly increases the first hyperpolarizability of the C4B32 nanocluster. Also, our results reveal that the first hyperpolarizability of the M@C4B32 nanoclusters can be progressively enhanced by increasing the atomic number of alkali metals. The effect of external electric fields on the nonlinear optical responses of the M@C4B32 has been systematically explored. We found that the first hyperpolarizability of the M@C4B32 compounds can be gradually increased by increasing the imposed external electric field from zero to the critical external electric field along the charge transfer direction (M→C4B32). Accordingly, this work presents an efficient strategy to improve the nonlinear optical responses of the heteroborospherenes. 相似文献
997.
998.
我们利用团簇动力学模型(IRadMat)研究了keV-He离子辐照金属铝的缺陷动力学和氦的聚集行为.通过对不同俘获类型(团簇、晶界和位错)俘获He浓度的定量分析,我们发现大多数He原子被晶界吸收,这成为铝在低辐照通量下发生脆化的主要原因.随着辐照能量的增加,He滞留峰的位置会变得更深.然而,随着辐照通量的增加,He在体内的滞留量会变得更多,但滞留深度的峰值位置不变.我们的结果表明,晶界的影响在He的滞留分布以及铝的脆化行为中起着关键作用,这也有助于我们理解He在金属中的动力学行为和损伤的分布. 相似文献
999.
Jie‐Lian Han Ying Qin Cheng‐Wei Ju Dongbing Zhao 《Angewandte Chemie (International ed. in English)》2020,59(16):6555-6560
Organosilicon compounds have been extensively utilized both in industry and academia. Studies on the syntheses of diverse organosilanes is highly appealing. Through‐space metal/hydrogen shifts allow functionalization of C?H bonds at a remote site, which are otherwise difficult to achieve. However, until now, an aryl to alkyl 1,5‐palladium migration process seems to have not been presented. Reported herein is the remote olefination, arylation, and borylation of a methyl group on silicon to access diverse vinyl‐, benzyl‐, and borylsilanes, constituting a unique C(sp3)?H transformation based on a 1,5‐palladium migration process. 相似文献
1000.