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991.
Dr. Vonika Ka-Man Au Shuk Ying Kwan Mio Nga Lai Dr. Kam-Hung Low 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(35):9174-9179
By using tritopic and ditopic organic linkers derived from the same 2,4,6-triphenylpyridine core, copper(II) metal-organic frameworks with different three-dimensional structures have been successfully synthesized under ambient conditions. The crystalline framework, PTB MOF ([Cu3(PTB)2(H2O)3]n, where H3PTB=4,4′,4′′-(pyridine-2,4,6-triyl)tribenzoic acid, was observed to be mesoporous in nature and exhibited dual functionality in the removal of organic dyes. While cationic dyes such as methylene blue and malachite green, which are of different sizes, were adsorbed by PTB MOF ; anionic dyes such as tartrazine could be effectively degraded in a photo-Fenton-like reaction catalyzed by the MOFs under irradiation with visible light. 相似文献
992.
Fang‐Che Hsueh Chi‐You Tsai Chien‐Chen Lai Yi‐Hung Liu Shie‐Ming Peng Sheng‐Hsien Chiu 《Angewandte Chemie (International ed. in English)》2020,59(28):11278-11282
We have prepared NHC‐CuI complexes with a rotaxane structure and used them as sterically sensitive catalysts for one‐pot sequential copper‐catalyzed azide/alkyne cycloadditions in solutions containing all of the coupling partners premixed in unprotected form. Most notably, a photolabile and sterically encumbered complex first catalyzed the coupling of a less bulky azide/alkyne pair; after removing the protective macrocyclic component from the rotaxane structure, through irradiation with light, the exposed dumbbell‐shaped NHC‐CuI complex catalyzed the second click reaction of a bulkier azide/alkyne pair. Using this approach, we obtained predominantly, from a single sealed pot, a bis‐triazole product (84 %) from a mixture of two sterically distinct azides and a diyne. 相似文献
993.
建立了适用于研究PI-LCX:1300型单光子计数型CCD量子效率及多像素事件的蒙特卡罗模拟模型,采用蒙特卡罗程序Geant4对0.5~30.0 keV能量区间的X射线在CCD芯片中的输运进行了模拟研究。研究了X射线在CCD芯片中的能量沉积谱,给出了CCD探测X射线的效率曲线,其结果与厂家提供的效率曲线一致。研究了Si片厚度对探测效率的影响,结果表明在有效探测范围内,Si片越厚探测效率越高,而对较高能量的X射线,此趋势不明显。研究了能量沉积分布在多个像素中的问题,结果表明周围像素中的能量沉积主要由中心像素的特征X射线及瑞利散射X射线所贡献,在5~30 keV之间X射线能量越高,能量沉积效率越低,多像素污染效果越弱。 相似文献
994.
Someswara Rao Kosuru Hsin‐Yu Lai Chien‐Yi Yang Gopal Chandru Senadi Yi‐Chun Lai Hsuan‐Ying Chen 《中国化学会会志》2019,66(1):110-113
The palladacycle complex [LsPdOAc]2 bearing 2‐phenyl benzothiazole was synthesized and characterized by NMR and X‐ray crystallography. [LsPdOAc]2 was used as a catalyst in the Suzuki–Miyaura cross coupling reaction of 4‐bromotoluene with phenylboronic acid, which resulted in a conversion of >90% with 5 mol% of the Pd complex within 10 min at 60°C. 相似文献
995.
Chen NC Huang PY Lai CC Liu YH Wang Y Peng SM Chiu SH 《Chemical communications (Cambridge, England)》2007,(40):4122-4124
We describe a [2]rotaxane molecule that exhibits distinct signals in its (1)H NMR spectra upon the complexation of physiologically important Li(+), Na(+), Mg(2+) and Ca(2+) ions; thus, the identification of these metal ions in solution is possible from the analysis of a single (1)H NMR spectrum of a single molecular sensor. 相似文献
996.
Chuan Yang Zhan Yuin Ong Yi‐Yan Yang Pui Lai Rachel Ee James L. Hedrick 《Macromolecular rapid communications》2011,32(22):1826-1833
A novel amine‐functionalized polycarbonate was synthesized and its excellent gene transfection ability in vitro is demonstrated. In the framework of adapting the cationic polycarbonate for in vivo gene delivery applications, here the design and synthesis of biodegradable block copolymers of poly(ethylene glycol) (PEG) and amine‐functionalized polycarbonate with a well‐defined molecular architecture and molecular weight is achieved by metal‐free organocatalytic ring‐opening polymerization. Copolymers in triblock cationic polycarbonate‐block‐PEG‐block‐cationic polycarbonate and diblock PEG‐block‐cationic polycarbonate configurations, in comparison with a non‐PEGylated cationic polycarbonate control, are investigated for their influence on key aspects of gene delivery. Among the polymers with similar molecular weights and N content, the triblock copolymer exhibit more favorable physicochemical (i.e., DNA binding, size, zeta‐potential, and in vitro stability) and biological (i.e., cellular uptake and luciferase reporter gene expression) properties. Importantly, the various cationic polycarbonate/DNA complexes are biocompatible, inducing minimal cytotoxicities and hemolysis. These results suggest that the triblock copolymer is a more useful architecture in future cationic polymer designs for successful systemic therapeutic applications. 相似文献
997.
Hsuan‐Ying Chen Wei‐Yi Lu Yen‐Jen Chen Sodio C. N. Hsu Siou‐Wei Ou Wei‐Te Peng Nai‐Yuan Jheng Yi‐Chun Lai Bo‐Sheng Wu Hsuan Chung Yun Chen Ta‐Chou Huang 《Journal of polymer science. Part A, Polymer chemistry》2013,51(2):327-333
This study synthesized a series of titanium iminophenoxide complexes and investigated their suitability as catalysts for the ring‐opening polymerization of L ‐lactide (L ‐LA) and ε‐caprolactone (CL). Complexes with bidentate ligands demonstrate higher catalytic activity than their tridentate counterparts since the third coordination atom needs to contend with L ‐LA and CL. Differences in the geometric framework of bidentate ligands also influence the catalytic activity. Type II ligands (N, N‐trans form of Ti complex) prevent the coordination of monomers to Ti thereby decreasing the initiation rate. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
998.
Lai Chun Wong Ross W. Harrington Stephen P. Stanforth 《Journal of heterocyclic chemistry》2013,50(5):1213-1216
Treatment of methyl 2‐aryl‐1,2,3,4‐tetrahydroisoquinoline‐3‐carboxylates 5 with N‐bromosuccinimide followed by heating in the presence of an acid catalyst resulted in the formation of the corresponding methyl 2‐aryl‐1,2‐dihydroisoquinoline‐3‐carboxylates 10 via an oxidation–dehydration sequence. 相似文献
999.
Jiayun Li Jiajian Peng Yuan Deng Chao Ma Guodong Zhang Ying Bai Guoqiao Lai 《应用有机金属化学》2012,26(9):461-466
Eight platinum acetylide complexes have been synthesized and characterized. The catalytic properties of these complexes in curing silicone rubber by hydrosilylation have been tested. Among the complexes tested, trans‐Pt(PPh3)2[―C≡CC(CH3)2OSi(CH3)3] 2 (2), trans‐Pt(PPh3)2[―C≡CC(CH3)2OSi(CH2CH3)3]2 (3), trans‐Pt(PPh3)2[―C≡CC(CH3)2OSiPh(CH3)2]2 (4), trans‐Pt(PPh3)2[―C≡C(C6H10)OSi(CH3)3]2 (6), trans‐Pt(PPh3)2[―C≡C(C6H10)OSi(CH2CH3)3]2 (7), and trans‐Pt(PPh3)2[―C≡C(C6H10)OSiPh(CH3)2]2 (8) exhibited sufficiently long pot‐lives (15 days) at room temperature and short silicone rubber curing times of 10–35 min at 100°C or 1–5 min at 120°C. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
1000.
Several carboxylated polyethylene glycols as promoters were applied in the platinum‐catalyzed hydrosilylation of alkenes, and polyethylene glycol maleic acid monoester as a promoter for hydrosilylation was investigated. It was found that an improvement of the selectivity was achieved in the presence of carboxylated polyethylene glycol, and the β‐adduct as major product was obtained. Additionally, the effect of alkenes and silanes employed on the selectivity was investigated; better selectivity could be achieved when (EtO)3SiH was used as the hydride than ClMe2SiH. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献