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108 results on '"Ren, Yingjie"'

104. Core/shell-structured TS-1@mesoporous silica-supported Au nanoparticles for selective epoxidation of propylene with H2and O2Electronic supplementary information (ESI) available. See DOI: 10.1039/c1jm10483g.

Author

Xu, Le, Ren, Yingjie, Wu, Haihong, Liu, Yueming, Wang, Zhendong, Zhang, Yingtian, Xu, Jiajia, Peng, Honggen, and Wu, Peng

Abstract

Hierarchically ordered materials with core/shell structures were synthesized through a layer-by-layer approach. The novel microporous/mesoporous hybrid materials were composed of a TS-1 zeolite particle for the core and mesoporous silica for the shell. The as-synthesized TS-1 crystals were modified with polydiallyldimethylammonium chloride to make their external surface positively charged, which induced an oriented self-assembly of tetraethoxysilane (TEOS) with cetyltrimethyl ammonium bromide on the TS-1 particle surface to form a shell of mesophase silica. The thickness of the mesoporous silica shell was controlled to be in the range 30–55 nm by changing the amount of TEOS added in the synthesis. The mesoporous channels in the shell were perpendicular to the zeolite core, which made the micropores inside the core accessible from the outside through the mesopores. Taking advantage of the confining effect of the mesopores, Au nanoparticles were incorporated into the shell, resulting in bifunctional catalysts which were more selective than conventional Au/TS-1 catalysts in the direct epoxidation of propylene to propylene oxide with H2and O2. [ABSTRACT FROM AUTHOR]

Published
2011
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106. Ga2O3/HZSM-48 for dehydrogenation of propane: Effect of acidity and pore geometry of support.

Author

Ren, Yingjie, Wang, Jie, Hua, Weiming, Yue, Yinghong, and Gao, Zi

Subjects
DEHYDROGENATION, GALLIUM catalysts, PROPANE, ACIDITY, ZEOLITES, CARBON dioxide
Abstract

Abstract: The catalytic performance of propane dehydrogenation over HZSM-48 supported Ga2O3 catalysts in the presence of CO2 was investigated, and compared with that of HZSM-5 supported ones. The activity decreases with the increase of Si/Al ratio of catalyst support while the selectivity to propene shows a contrary trend. Ga2O3/HZSM-48 with Si/Al ratio of 130 has the best propene yield of 22%. HZSM-48 supported catalysts exhibit higher selectivities to propene than the HZSM-5 supported ones at similar propane conversion, due to their weak acid strength. However, their stabilities are not so good as those of the latters, owing to their more weak acid sites and unidimensional pore structures. [Copyright &y& Elsevier]

Published
2012
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107. Promotion effect of niobium on ceria catalyst for selective catalytic reduction of NO with NH3

Author

Zhang, Bolin, Deng, Lifeng, Liebau, Michael, Ren, Yingjie, Luo, Chunyun, Liu, Bo, Zhang, Shengen, and Gläser, Roger

Abstract

The CeO2, Ce-Nb-Oxand Nb2O5catalysts were synthesized by citric acid method to investigate the promotion effect of Nb on ceria for selective catalytic reduction (SCR) of NO with NH3. The catalytic activity measurements indicate that the mixed oxide Ce-Nb-Oxpresents a higher SCR activity than the single oxide CeO2or Nb2O5catalyst. In addition, the Ce-Nb-Oxcatalyst shows a high resistance towards H2O and SO2at 280 °C. The Raman, X-ray photoelectron spectra and temperature programmed reduction with H2results indicate that the incorporation of Nb provides abundant oxygen vacancies for capturing more surface adsorbed oxygen, which provides a superior redox capability and accelerates the renewal of active sites. Furthermore, the Fourier transform infrared spectra and temperature programmed desorption of NH3results suggest that niobium pentoxide shows high surface acidity, which is partly retained in the Ce-Nb-Oxcatalyst possessing a high content of Lewis and Brønsted acid sites. Therefore, the incorporation of Nb improves both the redox and acidic capacities of Ce-Nb-Oxcatalyst for the SCR reaction. Here, the redox behavior is primarily taken on Ce and the acidity is well improved by Nb, so the synergistic effect should exist between Ce and Nb. In terms of the reaction mechanism, in situDRIFT experiments suggest that both NH3on Lewis acid sites and NH4+on Brønsted acid sites can react with NO species, and adsorbed NO and NO2species can both be reduced by NH3. In the SCR process, O2as an important role primarily acts as the accelerant to improve the redox and acid cycles. This work proves that the combination of redox and acidic properties of different constituents can be feasible for catalyst design to obtain a superior SCR performance.

Published
2021
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108. Therapeutic effect evaluation of reteplase on acute pulmonary embolism.

Author

Wang W, Zhao X, Ren Y, and Qiao P

Subjects
Acute Disease, Adult, Aged, Biomarkers blood, Female, Fibrinolytic Agents pharmacology, Humans, Inflammation Mediators antagonists & inhibitors, Male, Middle Aged, Pulmonary Embolism diagnosis, Recombinant Proteins pharmacology, Recombinant Proteins therapeutic use, Tissue Plasminogen Activator pharmacology, Treatment Outcome, Young Adult, Fibrinolytic Agents therapeutic use, Inflammation Mediators blood, Pulmonary Embolism blood, Pulmonary Embolism drug therapy, Tissue Plasminogen Activator therapeutic use
Abstract

Thrombolysis is the main therapeutic method of acute pulmonary embolism (APE). In order to investigate the efficacy of reteplase on APE and the changes of cytokines in the progression of APE, 72 patients with APE were randomized into reteplase group and urokinase group which received reteplase thrombolysis and urokinase thrombolysis, respectively. The clinical symptoms, blood pressure, heart rate (HR), blood gas index and cytokines of patients were observed before and after therapy for assessing the thrombolysis effect of each group; blood level of high sensitive C-reactive protein (hs-CRP), TNF-α, IL-1β, IL-6 and IL-10 was detected at 0h, 2h, 6h, 12h and 24h after thrombolysis. After treatment, the clinical symptoms of both groups were alleviated obviously; PaO 2 , PaCO 2 , blood pressure and HR in both groups were significantly improved than those before treatment (p<0.001), and reteplase group showed a more obvious improvement than urokinase group (p<0.001). Since 6h after therapy, the content of hs-CRP, IL-1β and IL-6 in patients of reteplase group declined significantly (p<0.05 or 0.01). In conclusion, therapeutic effect of reteplase is better than urokinase, hs-CRP, IL-1β and IL-6 can be used to monitor the thrombolysis efficacy of APE patients.

Published
2018

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