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991.
Li‐Hong Zhang Tao Jiang Dr. Lian‐Bin Wu Dr. Jun‐Hua Wan Dr. Chih‐Hsien Chen Dr. Yong‐Bing Pei Dr. Hua Lu Yuan Deng Gao‐Feng Bian Prof. Hua‐Yu Qiu Prof. Guo‐Qiao Lai 《化学:亚洲杂志》2012,7(7):1583-1593
A series of linear 2,5‐tetraphenylsilole‐vinylene‐type polymers were successfully synthesized for the first time. The tetraphenylsilole moieties were linked at their 2,5‐positions through a vinylene bridge with p‐dialkoxybenzenes to obtain polymer PSVB and with 3,6‐carbazole to obtain polymer PSVC . For comparison, 2,5‐tetraphenylsilole‐ethyne‐type polymer PSEB was also synthesized, in which the vinylene bridge of PSVB was replaced with an ethyne bridge. Very interestingly, the bridging group (vinylene or ethyne) had a significant effect on the photophysical properties of the corresponding polymers. The fluorescence peak of PSEB at 504 nm in solution originated from the emission of its silole moieties, whereas PSVB and PSVC emitted yellow light and no blueish–green emission from the silole moieties was observed, thus demonstrating that the emissions of PSVB and PSVC were due to their polymer backbones. More importantly, the 2,5‐tetraphenylsilole‐ethyne polymer exhibited a pronounced aggregation‐enhanced emission (AEE) effect but the 2,5‐tetraphenylsilole‐vinylene polymer was AEE‐inactive. Moreover, both AEE‐active 2,5‐tetraphenylsilole‐ethyne polymer and AEE‐inactive 2,5‐tetraphenylsilole‐vinylene polymers were successfully applied as fluorescent chemosensors for the detection of explosive compounds. 相似文献
992.
993.
994.
Hu Yue Zhi Meiting Zeng Ziqing Lu Wenguan Lai Yinlong Wang Xiaobing 《Research on Chemical Intermediates》2022,48(3):935-948
Research on Chemical Intermediates - In this study, the removal of Cr(VI) using commercial FeS with the partially oxidized surface was investigated under visible light. The results demonstrated... 相似文献
995.
A simple, robust, and accurate HLLC-type Riemann solver for the compressible Euler equations at various Mach numbers is built. To cure shock instability of the HLLC solver at strong shocks, a pressure-control technique, which plays a role in limiting the propagation of erroneous pressure perturbation, is proposed. With an all Mach correction method for the compressible Euler system, the proposed method is further extended to compute flow problems at low Mach numbers. The proposed all Mach HLLC-type scheme has been implemented and used to compute a variety of flow problems ranging from hypersonic compressible to low Mach incompressible flow regimes. Various numerical results demonstrate that the obtained all Mach HLLC-type scheme is both accurate and stable for all speed ranges. 相似文献
996.
997.
Electrochemical Synthesis of Benzazoles from Alcohols and o‐Substituted Anilines with a Catalytic Amount of CoII Salt 下载免费PDF全文
Yin‐Long Lai Prof. Dr. Jian‐Shan Ye Prof. Dr. Jing‐Mei Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(15):5425-5429
An electrochemical synthesis of benzazoles directly from alcohols and o‐substituted anilines has been developed. The reaction conditions have been optimized by varying the composition of the electrolyte and the metal salt used as catalyst. The cyclization proceeds smoothly with a catalytic amount of a cobalt salt under air at room temperature to afford 2‐substituted benzimidazoles, benzothiazoles, and benzoxazoles in good to excellent yields with a wide substrate scope. 相似文献
998.
999.
高碘酸钠-过氧化氢-盐酸黄连素化学发光体系的研究 总被引:5,自引:0,他引:5
1引言 盐酸黄连素是一种用于治疗肠道感染,毒性低、副作用小的天然药物。对盐酸黄连素的测定,化学发光法未见报道。本文发现,过氧化氢存在下,磷酸介质中盐酸黄连素与高碘酸钠反应产生强的化学发光。据此结合流动注射技术建立了在NaIO4-H3PO4-H2O2-盐酸黄连素体系中测定盐酸黄连素的化学发光新方法。方法的检出限为 3.8×10-9g/mL。线性范围是 1.0× 10-8- 7.0 ×10-6g/mL。相对标准偏差为 2.3%( C8= 1. 0 ×10-6g/mL; n=11)。该法与药典方法对照,结果满意。… 相似文献
1000.
Glen B. Deacon Prof. Dr. Lai Yoong Goh Prof. Dr. W. Roy Jackson Brian W. Skelton Wei Chen Allan H. White 《无机化学与普通化学杂志》2010,636(8):1478-1483
Monomeric manganese(II) complexes of bulky alkyl/ aryl‐substituted phenoxides, [Mn{C6HnRmO}2(DME)] [ 1 : R = C6H5, n = 3, m = 2 (2,6); 2 : R = Me3C, n = 3, m = 2 (2,6); 3 : R = Me3C, n = 2, m = 3 (2,4,6)] were prepared in yields of 37, 44 and 72 %, respectively, from the reaction of manganese powder, Hg(C6F5)2 and the corresponding phenol in the presence of a little mercury in dimethoxyethane (DME). The compounds were characterized spectroscopically and by magnetic measurements. The single crystal structures of 1 and 3 and also of the mixed phenoxide complex [Mn{(C6H3(C6H5)2‐2,6‐O}{C6H3(Me3C)2‐2,6‐O}(DME)] 4 are reported. 相似文献