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991.
Sulfur Encapsulated in a TiO2‐Anchored Hollow Carbon Nanofiber Hybrid Nanostructure for Lithium–Sulfur Batteries 下载免费PDF全文
Prof. Zhian Zhang Qiang Li Shaofeng Jiang Dr. Kai Zhang Prof. Yanqing Lai Prof. Jie Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(3):1343-1349
A hollow carbon nanofiber hybrid nanostructure anchored with titanium dioxide (HCNF@TiO2) was prepared as a matrix for effective trapping of sulfur and polysulfides as a cathode material for Li–S batteries. The synthesized composites were characterized and examined by X‐ray diffraction, nitrogen adsorption–desorption measurements, field‐emission scanning electron microscopy, scanning transmission electron microscopy, and electrochemical methods such as galvanostatic charge/discharge, rate performance, and electrochemical impedance spectroscopy tests. The obtained HCNF@TiO2–S composite showed a clear core–shell structure with TiO2 nanoparticles coating the surface of the HCNF and sulfur homogeneously distributed in the coating layer. The HCNF@TiO2–S composite exhibited much better electrochemical performance than the HCNF–S composite, which delivered an initial discharge capacity of 1040 mA h g?1 and maintained 650 mAh g?1 after 200 cycles at a 0.5 C rate. The improvements of electrochemical performances might be attributed to the unique hybrid nanostructure of HCNF@TiO2 and good dispersion of sulfur in the HCNF@TiO2–S composite. 相似文献
992.
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
993.
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
994.
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
995.
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
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Prof. Dr. Sunney I. Chan Yu‐Jhang Lu Dr. Penumaka Nagababu Dr. Suman Maji Mu‐Cheng Hung Marianne M. Lee Prof. Dr. I‐Jui Hsu Pham Dinh Minh Jeff C.‐H. Lai Kok Yoah Ng Sridevi Ramalingam Prof. Dr. Steve S.‐F. Yu Prof. Dr. Michael K. Chan 《Angewandte Chemie (International ed. in English)》2013,52(13):3731-3735
1000.
In this work, low-temperature vulcanized, transparent silane modified epoxy resins for LED filament bulb package were prepared. Firstly, transparent silane modified epoxy resins were produced through a controllable sol-gel method using γ-(2,3-epoxypropoxy)propytrimethoxysilane and dimethyldiethoxylsilane. The features of the reaction were investigated and the products were characterized in detail. Subsequently, various curing agents were explored to prepare transparent silane modified epoxy resins. The silane modified epoxy resins cured by PEA-230 at a fairly low temperature(40 °C/2 h then 60 °C/1 h) exhibited excellent thermal stability with a thermal degradation temperature as high as 316.5 °C and adjustable hardness between 40-60 shore A. The application tests showed the materials obtained were good candidates for LED filament bulb package. 相似文献