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991.
Singh S Chai J Pal A Jancik V Roesky HW Herbst-Irmer R 《Chemical communications (Cambridge, England)》2007,(46):4934-4936
The first examples of base free lithium-organoaluminate and the corresponding gallium compound [LM(Me)OLi]3 (M = Al (3), Ga (4); L = HC{C(Me)N-2,6-iPr2C6H3}2) have been prepared by the reaction of Li[N(SiMe3)2] with the corresponding metal hydroxides LM(Me)OH (M = Al (1), Ga(2)); the oxygen atom in the M-O-Li fragment exists as oxide ion and is involved in the central Li3O3 six-membered ring formation. 相似文献
992.
Afanasiev S Aidala C Ajitanand NN Akiba Y Alexander J Al-Jamel A Aoki K Aphecetche L Armendariz R Aronson SH Averbeck R Awes TC Azmoun B Babintsev V Baldisseri A Barish KN Barnes PD Bassalleck B Bathe S Batsouli S Baublis V Bauer F Bazilevsky A Belikov S Bennett R Berdnikov Y Bjorndal MT Boissevain JG Borel H Boyle K Brooks ML Brown DS Bucher D Buesching H Bumazhnov V Bunce G Burward-Hoy JM Butsyk S Campbell S Chai JS Chernichenko S Chiba J Chi CY Chiu M Choi IJ Chujo T Cianciolo V Cleven CR 《Physical review letters》2007,99(5):052301
Differential elliptic flow (v(2)) for phi mesons and (anti)deuterons (d)d is measured for Au+Au collisions at square root of sNN=200 GeV. The v(2) for phi mesons follows the trend of lighter pi+/- and K+/- mesons, suggesting that ordinary hadrons interacting with standard hadronic cross sections are not the primary driver for elliptic flow development. The v(2) values for (d)d suggest that elliptic flow is additive for composite particles. This further validation of the universal scaling of v(2) per constituent quark for baryons and mesons suggests that partonic collectivity dominates the transverse expansion dynamics. 相似文献
993.
994.
Tingting Chai Hualin Zhao Shuming Yang Min Wang 《International journal of environmental analytical chemistry》2015,95(12):1124-1133
Carbosulfan (CAS) is used as an insecticide on vegetables, but its toxicity might increase due to the formation of higher toxic metabolites including carbofuran (CAN), 3-hydroxycarbofuran (3-OH) and 3-ketocarbofuran (3-KETO). In this study, the transformation of CAS to its metabolites in pakchoi (Brassica campestris ssp.) and cucumber (Cucumissativus L.) was investigated in the field in Beijing and Changsha and in a greenhouse in Hangzhou. CAS was metabolised to CAN, 3-OH and 3-KETO in pakchoi but only to CAN and 3-OH in cucumber. In pakchoi, the degradation of CAS (as measured by the DT50 value, the time marking the disappearance of 50% of the pesticide) was the fastest in Hangzhou (0.7 d), followed by Changsha (1.4 d) and Beijing (2.3 d), whereas in cucumber, its degradation was the fastest in Changsha (1.6 d) and Hangzhou (1.6 d), followed by Beijing (2.5 d). These results suggested the monitoring of metabolites should be a prior objective for CAS, and different metabolites should be considered when assessing the risk of CAS in different vegetables. 相似文献
995.
Jun Chai Bo Long Xiaomei Liu Yan Li Ning Han Ping Zhao Weimin Chen 《Experimental & molecular medicine》2015,47(6):e167
Pulmonary dysfunction caused by ischemia-reperfusion injury is the leading cause of mortality in lung transplantation. We aimed to investigate the effects of sevoflurane pretreatment on lung permeability, tight junction protein occludin and zona occludens 1 (ZO-1) expression, and translocation of protein kinase C (PKC)-α after ischemia–reperfusion. A lung ischemia-reperfusion injury model was established in 96 male Wistar rats following the modified Eppinger method. The rats were divided into four groups with 24 rats in each group: a control (group C), an ischemia-reperfusion group (IR group), a sevoflurane control group (sev-C group), and a sevoflurane ischemia-reperfusion group (sev–IR group). There were three time points in each group: ischemic occlusion for 45 min, reperfusion for 60 min and reperfusion for 120 min; and there were six rats per time point. For the 120-min reperfusion group, six extra rats underwent bronchoalveolar lavage. Mean arterial pressure (MAP) and pulse oxygen saturation (SpO2) were recorded at each time point. The wet/dry weight ratio and lung permeability index (LPI) were measured. Quantitative RT-PCR and Western blot were used to measure pulmonary occludin and ZO-1, and Western blot was used to measure cytosolic and membranous PKC-α in the lung. Lung permeability was significantly increased after ischemia–reperfusion. Sevoflurane pretreatment promoted pulmonary expression of occludin and ZO-1 after reperfusion and inhibited the translocation of PKC-α. In conclusion, sevoflurane pretreatment alleviated lung permeability by upregulating occludin and ZO-1 after ischemia–reperfusion. Sevoflurane pretreatment inhibited the translocation and activation of PKC-α, which also contributed to the lung-protective effect of sevoflurane. 相似文献
996.
Dr. Jinshui Zhang Dr. Song‐Hai Chai Dr. Zhen‐An Qiao Dr. Shannon M. Mahurin Dr. Jihua Chen Dr. Youxing Fang Dr. Shun Wan Kimberly Nelson Dr. Pengfei Zhang Prof. Sheng Dai 《Angewandte Chemie (International ed. in English)》2015,54(3):932-936
A porous liquid containing empty cavities has been successfully fabricated by surface engineering of hollow structures with suitable corona and canopy species. By taking advantage of the liquid‐like polymeric matrices as a separation medium and the empty cavities as gas transport pathway, this unique porous liquid can function as a promising candidate for gas separation. Moreover, such a facile synthetic strategy can be further extended to the fabrication of other types of nanostructure‐based porous liquid, opening up new opportunities for preparation of porous liquids with attractive properties for specific tasks. 相似文献
997.
Yuanyuan Li Dr. Xiao He Prof. Jun‐Jie Yin Dr. Yuhui Ma Dr. Peng Zhang Dr. Jingyuan Li Dr. Yayun Ding Dr. Jing Zhang Prof. Yuliang Zhao Prof. Zhifang Chai Prof. Zhiyong Zhang 《Angewandte Chemie (International ed. in English)》2015,54(6):1832-1835
Ceria nanoparticles (nanoceria) are well known as a superoxide scavenger. However, inherent superoxide‐scavenging ability has only been found in the nanoceria with sizes of less than 5 nm and with very limited shape diversity. Reported herein is a strategy to significantly improve the superoxide‐scavenging activity of nanoceria sized at greater than 5 nm. The nanoceria with sizes of greater than 5 nm, with different shapes, and with a negligible Ce3+/Ce4+ ratio can acquire remarkable superoxide‐scavenging abilities through electron transfer. This method will make it possible to develop nanoceria‐based superoxide‐scavengers with long‐acting activity and tailorable characteristics. 相似文献
998.
Dr. Jinshui Zhang Dr. Zhen‐An Qiao Dr. Shannon M. Mahurin Dr. Xueguang Jiang Dr. Song‐Hai Chai Dr. Hanfeng Lu Kimberly Nelson Prof. Sheng Dai 《Angewandte Chemie (International ed. in English)》2015,54(15):4582-4586
A soft chemistry synthetic strategy based on a Friedel–Crafts alkylation reaction is developed for the textural engineering of phenolic resin (PR) with a robust mesoporous framework to avoid serious framework shrinkage and maximize retention of organic functional moieties. By taking advantage of the structural benefits of molecular bridges, the resultant sample maintains a bimodal micro‐mesoporous architecture with well‐preserved organic functional groups, which is effective for carbon capture. Moreover, this soft chemistry synthetic protocol can be further extended to nanotexture other arene‐based polymers with robust frameworks. 相似文献
999.
Silver‐Catalyzed Cross‐Coupling of Isocyanides and Active Methylene Compounds by a Radical Process
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Jianquan Liu Zhenhua Liu Dr. Peiqiu Liao Dr. Lin Zhang Prof. Tao Tu Prof. Xihe Bi 《Angewandte Chemie (International ed. in English)》2015,54(36):10618-10622
Isocyanides are versatile building blocks, and have been extensively exploited in C? H functionalization reactions. However, transition‐metal‐catalyzed direct C? H functionalization reactions with isocyanides suffer from over‐insertion of isocyanides. Reported herein is a radical coupling/isomerization strategy for the cross‐coupling of isocyanides with active methylene compounds through silver‐catalysis. The method solves the over‐insertion issue and affords a variety of otherwise difficult to synthesize β‐aminoenones and tricarbonylmethanes under base‐ and ligand‐free conditions. This report presents a new fundamental C? C bond‐forming reaction of two basic chemicals. 相似文献
1000.
Identifying Different Types of Catalysts for CO2 Reduction by Ethane through Dry Reforming and Oxidative Dehydrogenation
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Dr. Marc D. Porosoff Myat Noe Zin Myint Dr. Shyam Kattel Zhenhua Xie Elaine Gomez Dr. Ping Liu Prof. Dr. Jingguang G. Chen 《Angewandte Chemie (International ed. in English)》2015,54(51):15501-15505
The recent shale gas boom combined with the requirement to reduce atmospheric CO2 have created an opportunity for using both raw materials (shale gas and CO2) in a single process. Shale gas is primarily made up of methane, but ethane comprises about 10 % and reserves are underutilized. Two routes have been investigated by combining ethane decomposition with CO2 reduction to produce products of higher value. The first reaction is ethane dry reforming which produces synthesis gas (CO+H2). The second route is oxidative dehydrogenation which produces ethylene using CO2 as a soft oxidant. The results of this study indicate that the Pt/CeO2 catalyst shows promise for the production of synthesis gas, while Mo2C‐based materials preserve the C? C bond of ethane to produce ethylene. These findings are supported by density functional theory (DFT) calculations and X‐ray absorption near‐edge spectroscopy (XANES) characterization of the catalysts under in situ reaction conditions. 相似文献