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Dehydrogenation of n-butane over vanadia catalysts supported on silica gel

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Journal of Natural Gas Chemistry 2009年第1期18卷 88-93页

作者： Yuebing Xu Jiangyin Lu mei zhong Jide Wang Key Laboratory of Oil ＆ Gas Fine Chemicals Ministry of Education Xinjiang University 14# Shengli Road Urumqi 830046 Xinjiang China

VOx/SiO2 catalysts prepared by impregnation method were used for catalytic dehydrogenation of n-butane to butenes and characterized by X-ray diffraction, FT-IR, UV-vis, Raman, and BET measurements. The effects of VOx loading and the reaction temperature on the VOx/SiO2 catalysts and their catalytic performances for the dehydrogenation of n-butane were studied. When the VOx loading was 12% g/gcat and reaction temperature was between 590 ℃ and 600℃, n-butane conversion and butenes yields reached the highest value under H2 flux of 10 ml/min and n-butane flux of 10 ml/min. Product distribution, such as the ratio of 2-butene to 1-butene and the ratio of cis-2-butene to trans-2-butene, was mainly influenced by the reaction temperature.

关键词： n-butane catalytic dehydrogenation butene VOx supported SiO2

Optimization and mechanism of gold-bearing sulfide flotation

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Rare Metals 2014年第3期33卷 363-368页

作者： zhong-mei Sun Chun-Bao Sun Ji-Zhen Wang Wan-zhong Yin School of Civil and Environmental Engineering University of Science and Technology Beijing Zijin Research Institute of Mining and Metallurgy School of Materials & Metallurgy Northeastern University College of Zi Jin Mining Fuzhou University

In order to overcome the difficulty of extracting gold from gold-bearing sulfide ore by cyanide process flotation was adopted based on mineralogical analysis Mineralogy shows that gold particles are of superfine structure and mainly enclosed by sulfide ores. Primary gold-bearing sulfide ore is fine-grained pyrite and arsenopyrite. The paper describes the effects of ratios and dosage of activators and collectors on the recovery and grade of gold concentrate. A proper flotation flowsheet was then proposed based on experimental condition and closedcircuit test. The gold concentrate with the gold grade of25.14 g ton-1and the recovery of 86.94 % is obtained after one rougher, three cleaners, and four scavengers from fine grinding flotation process. Furthermore, the mechanisms of combined activators and combined collectors were studied by thermodynamic calculation, and structure-activity relationship of flotation reagent was also explained

关键词： Gold Pyrite Arsenopyrite Activator Combined reagent Flotation

Porous carbon from vinegar lees for phenol adsorption

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Particuology 2012年第1期10卷 35-41页

作者： mei zhong Yin Wang Jian Yu Yajun Tian Guangwen Xu State Key Laboratory of Multi-Phase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China Chemistry and Chemical Engineering Department Xinjiang University Xinjiang 830046 China

An effective technology for utilizing vinegar lees （VL）, a biomass waste generated during its production, is much needed in China due to the huge consumption of vinegar. This study investigates the preparation of porous carbon （PC） from VL, now reporting on the adsorption capability of PC in removing phenol from its aqueous solution. The preparation of PC consists of carbonization of VL in N2 and activation in CO2. The results show that the optimal activation temperature and time in CO2 for VL char carbonized at 800 ℃ were 875 ℃ and 1 h, respectively. The PC prepared was found to have large specific surface area and micropore volume, with an adsorptive capacity for phenol from its aqueous solution much higher than that of commercial coconut shell activated carbon （CSAC）. Adsorption of phenol from its aqueous solution by the VL-based PC was found to follow the isothermal Langmuir equation.

关键词： Porous carbonCarbonizationVinegar leesPhenolWaste water

Photochemical Reduction of Aromatic Imines by 2-Phenyl-N, N-dimethylbenzimidazoline

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Chinese Chemical Letters 2001年第4期12卷 307-308页

作者： mei zhong JIN Li YANG Long Ming WU You Chen LIU zhong Li LIU National Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000

A series of aromatic imines were reduced to corresponding amines in excellent yields by 2-phenyl-N. N-dimethylbenzimidazoline (PDMBI) photochemically in the presence of magnesium perchloride (Mg(ClO4)(2)). A Mg2+ medi... 详细信息

关键词： Photoinduced electron transfer selective reduction imine PDMBI

Photochemical Selective Desilylation of t-Butyldimethylsilyl Ethers

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Chinese Chemical Letters 2001年第2期12卷 95-98页

作者： mei zhong JIN Li YANG Long Ming WU You Cheng LIU zhong Li LIU National Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000

A photochemical desilylation reaction with nearly quantilative yield and excellent selectivity between silyl alkyl ether and silyl enol ether is reported.

关键词： photoinduced electron transfer selective desilylation

A New Cyclohexene Oxide from Uvaria tonkinensis ***

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Chinese Chemical Letters 2003年第11期14卷 1144-1145页

作者： An LIU zhong mei ZOU Li Zhen XU Shi Lin YANG Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100094

A new compound, subglain B, was isolated from the stems of Uvaria tonkinensis var. subglabra and its structure was identified as 1S, 2R, 3S, 6R-1-benzoyloxymethylene-1,2- dihydroxy-3-benzoyloxy-6-chlorocyclohex-4-ene ... 详细信息

关键词： Uvaria tonkinensis var subglabra subglain B cyclohexene.

Comparison of the rise of water level in the typical catchments,Three Gorges Reservoir area

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Journal of Mountain Science 2016年第4期13卷 715-724页

作者： SUN Hong-yang LIAO Xiao-yong XIA zhong-mei HE Jing Institute of Mountain Hazards and Environment Chinese Academy of Sciences and Ministry of Water ResourcesChengdu 610o41China Sichuan Academy of Agricultural Sciences Institute of Biotechnology and Nucleic TechnologyChengdu 610066China. Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041China

Water level is an important index for studying hydrologic processes. Water level rise processes were studied in three catchments(catchment I, II, III in Chen Jiagou watershed in the Three Gorge Reservoir Area) with different areas to provide useful information to inform data extension from a gauged-catchment to an ungauged catchment. The results showed that there are seasonal changes in the dominant driving mode of the rise of the water level. The rise of the water level in March is likely mainly driven by the mode of stored-full runoff, and in September or October, it is mainly driven by Horton-flow. The correlation coefficients of all indexes were significant among the three catchments, suggesting that these catchments have similarities and that water level data extension is likely to be completed successfully between the large catchment(III-Catchment) and the small catchment(ICatchment). It was confirmed that there is good similarity between the 0.6 km^2 and 6 km^2 catchments, and the data correlation is good between the catchments with the area differences in the Three Gorges Reservoir Area. In addition, the rise processes of the water level in the catchments were not only different under the same rain conditions, but this difference could also change with the rain condition.

关键词： Water level Precipitation Runoff Spearman-correlation coefficients Three Gorge Reservoir

Isolation and Characterization of Two New Compounds from Lysimachia Davurica

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Chemical Research in Chinese Universities 2005年第5期21卷 549-551页

作者： TIAN Jing-kui ZOU zhong-mei XU Li-zhen YANG Shi-lin Department of Chinese Medicine Science and Engineering Zhefiang University Hangzhou 310027P. R. China Institute of Medicinal Plants Development Chinese Academy of Medical Scienees and Peking Union Medical College Beijing 100094 P. R. China

Two new saponins named davuricoside H and davuricoside K were isolated from the whole plant of Lysimachia davurica. The structures of davuricoside H and davuricoside K were determined by 1-D and 2-D NMR, MS techniques, and chemical methods to be 3β,16α ,28-trihydroxy-olean-12-en-30-oic acid-3-O-β-D-glucopyranosyl-（ 1→2 ）- [β-D-glucopyranosyl-（ 1 → 4 ） ] -α-L-arabinopyranoside and 3β,16or ,28-trihydroxy-olean-12-en-30-oic acid-3-O-{β-D- glucopyranosyl- （ 1 →2 ） - [β-D-glucopyranosyl- （ 1 →4 ） ] -α-L-arabinopyranosyl } -30-O-β-D-glucopyranosyl-ester.

关键词： Lysimachia davurica Triterpenoid saponin Davuficoside H Davuricoside K

Infliximab treatment of glycogenosis Ib with Crohn's-like enterocolitis: A case report

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World Journal of Clinical Cases 2021年第19期9卷 5280-5286页

作者： You-Zhe Gong Xue-mei zhong Ji-Zhen Zou Gastroenterology Department Capital Institute of PediatricsBeijing 100020China Pathology Department Capital Institute of PediatricsBeijing 100020China

BACKGROUND Glycogen storage disease type Ib(GSD-Ib)is a glycogen metabolism disorder that leads to the manifestations of inflammatory bowel disease(IBD),especially Crohn’s disease(CD)-like *** biological agents are effective for treating CD,their application in the treatment of GSD-Ib with CD-like colitis has been rarely *** SUMMARY A 13-year-old Han male was diagnosed with GSD-Ib with *** patient was treated with granulocyte colony-stimulating *** he had symptoms of CD-like colitis,he was continuously pumped with enteral nutrition and administered oral mesalazine for 2 wk;however,the symptoms did not improve ***,infliximab(IFX)was ***,the patient has been followed up for 1 year,and no clinical manifestations have been *** 6 mo of treatment(fifth IFX treatment),the disease activity index and all inflammatory indexes decreased,and a review of the colonoscopy data showed that the ulcers appeared *** In this study,the patient was successfully treated with *** cases of GSD-Ib,IBD should be highly considered.

关键词： Crohn’s disease Glycogen storage disease type I Treatment Infliximab Case report