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Propylene Polymerization Catalysts with Sulfonyl Amines as Internal Electron Donors

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China Petroleum Processing & Petrochemical Technology 2013年第2期15卷 19-23页

作者： Wang liang Yin Baozuo Yi Jianjun Cui chunming State Key Laboratory of Elemento-Organic Chemistry Nankai University Petrochemical Research Institute Petro China

Three sulfonyl aliphatic amines [（R2SO2）2NR1, viz.： compound 1, in which RI=Me, and R2=Ph; compound 2, in which R1=n-Bu, and R2=CF3; and compound 3, in which RI=C8H17, and R2=CF3], have been synthesized and employed as internal electron donors （IED） for the preparation of Ziegler-Natta catalysts for the polymerization of propylene. The contents of Ti, H and C in these catalysts have been determined by elemental analysis and UV-vis spectrophotometry. The effect of the structure and dosage of the electron donor, the A1/Ti ratio and the polymerization temperature on the catalyst performance has been studied. Under optimized conditions, the catalyst with a highest activity yielded polypropylene with high isotacticity in the absence of external electron donors.

关键词： heterogeneous catalyst polypropylene internal electron donor polymerization

Study on Property of Polypropylene Catalyst with New Internal Donor

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China Petroleum Processing & Petrochemical Technology 2011年第4期13卷 70-73页

作者： Yin Baozuo Wang liang Yi Jianjun Cui chunming Petrochemical Research Institute PetroChina Beijing 100195 Nankai University Tianjin 100072

A P-substituted sulfonyl-containing compound was synthesized in the lab. The structure of the compound was demonstrated by 1H and 31P NMR. The propylene polymerization catalysts were prepared by incorporating an internal donor, and the content of Ti, H and C in the catalysts was also checked by elemental analysis. The effect of dosage of the donor, the Al/Ti ratio and the polymerization temperature on the catalyst activity were studied, the results suggested that the dosage of donor, the Al/Ti ratio and the polymerization temperature could affect not only the activity of catalyst but also the isotacticity index of the polymer. A catalyst with high activity was selected, and the polypropylene formed in the presence of this catalyst had high isotacticity index.

关键词： heterogeneous catalyst polypropylene donor polymerization

Separator Material Chosen for MH/Ni Battery

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Journal of Rare Earths 2004年第Z1期22卷 349-351页

作者： Xu Shaoping Ma Yijun liang Wanlong Liu Dong Jia chunming Inner Mongolia Rare Earth Ovonic High-Power MH/Ni Battery Co. Ltd. Baotou 014030 China Inner Mongolia Rare Earth Ovonic High-Power MH/Ni Battery Co. Ltd.Baotou 014030 China Inner Mongolia Rare Earth Ovonic High-Power MH/Ni Battery Co. Ltd.Baotou 014030 China Inner Mongolia Rare Earth Ovonic High-Power MH/Ni Battery Co. Ltd.Baotou 014030 China Inner Mongolia Rare Earth Ovonic High-Power MH/Ni Battery Co. Ltd.Baotou 014030 China

The properties of MH/Ni batteries using different separator were *** then an idea for choosing separator for high-power MH/Ni battery was *** the separator with grafting treatment, the storage characteristic, charge retention characteristic and anti-soft-short characteristic of high-power MH/Ni battery are *** and spunfibre material meet different properties requirement of battery.

关键词： separator material properties of battery storage characteristic

深圳地区社区健康服务中心上转院前急救患者病种、病情分析

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中国社区医师 2014年第8期30卷 156-157+159页

作者：黄远泉丘锦彪周育瑾林晓元梁春鸣广东医学院附属西乡人民医院劳动社区健康服务中心广东医学院附属西乡人民医院急诊科

目的:通过对深圳地区社区健康服务中心(简称社康中心,下同)上转院前急救患者病种、病情进行分析,总结社区院前急救患者特点,探讨医院与社区卫生服务机构在一个经济实体的条件下,如何实现患者在二者之间合理分配、医疗资源合理利用。方法... 详细信息

目的:通过对深圳地区社区健康服务中心(简称社康中心,下同)上转院前急救患者病种、病情进行分析,总结社区院前急救患者特点,探讨医院与社区卫生服务机构在一个经济实体的条件下,如何实现患者在二者之间合理分配、医疗资源合理利用。方法:回顾性分析西乡人民医院急诊科及下属38所社康中心实施院前急救协同双向接诊的5391例患者的临床资料,并进行对照分析。结果:5年间社康中心院前急救出诊共8025人次,接回上转患者5391例,占出诊人次67.1%,上转患者病因前3位分别为心血管系统疾病94.5%、呼吸系统疾病90.6%、神经系统疾病90.5%。结论:加强社区急救网络建设,普及社康中心医护人员急救知识,发挥社康中心院前急救功能,可提高急救成功率,降低社区院前急救患者死亡率和致残率。

关键词：社区卫生服务院前急救双向转诊病种

Mechanism transformation of cyclohexene-thiophene competitive adsorption in FAU zeolite

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Chinese Journal of Chemical Engineering 2021年第11期34卷 68-78页

作者： Pei Xue Meng Zheng Longwei Wang Liyuan Cao liang Zhao Jinsen Gao chunming Xu State Key Laboratory of Heavy Oil Processing China University of Petroleum(Beijing)Beijing 102249China

Competition of hydrocarbon compounds with sulfides in gasoline has caused a not very high selectivity of sulfides in adsorption desulfurization so far,resulting in a reduction of catalyst lifetime as well as more sulfur oxide *** the whole competitive process changing with the increase of the loading,the dynamic competition adsorption mechanism of cyclohexene and thiophene in siliceous faujasite(FAU)zeolite was analyzed by the Monte Carlo *** results showed that with the increase of the loading,thiophene and cyclohexene had different performances before and after the inflection point of 40 molecule/*** adsorbates were distributed ideally at optimal sites during the stage that occurred before the inflection point,which is called the“optimal-displacement adsorption”*** approaching the inflection point,the competition became apparent and the displacement appeared accordingly,some thiophene molecules at S sites(refers to the sites inside the supercages)were displaced by *** the inflection point,the concentration of adsorbates at W sites(refers to the 12-membered ring connecting the supercages)was significantly reduced,whereas the adsorbates at S sites got more *** stage some cyclohexene molecules displaced by thiophene and inserted into the center of the supercage can be named as the“insertion-displacement adsorption”stage,and both the adsorption behavior and the competitive relationship became localized when the adsorption amount became *** shift in the competitive adsorption mechanism was due to the sharp increase of interaction energy between the ***,the increase in temperature and ratio of Si/Al will allow the adsorbates,especially thiophene molecules to occupy more adsorption sites,and it is beneficial to improve the desulfurization selectivity.

关键词： Competitive adsorption mechanism Cyclohexene Thiophene FAU zeolite Molecular simulation Selectivity

Joint shape and color descriptors for 3D urban model retrieval

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International Journal of Digital Earth 2016年第11期9卷 1117-1134页

作者： liang Zhang Liqiang Zhang Xiaojing Yao P.Takis Mathiopoulos chunming Han State Key Laboratory of Remote Sensing Science Beijing Normal UniversityBeijingPeople’s Republic of China The Institute of Remote Sensing and Digital Earth Chinese Academy of SciencesBeijingPeople’s Republic of China Department of Informatics and Telecommunications University of AthensAthensGreece

With the rapid development of photogrammetry,computer vision and three-dimensional(3D)modeling technologies,it is possible to efficiently construct detailed 3D urban ***,large corpora of 3D models,such as the Google 3D Warehouse,are now becoming freely available on the *** to find the proper 3D urban models is a challenging research *** this paper,we join shape descriptors and color descriptors for 3D urban model *** query objects are localized and segmented automatically from the input images by using a new selective search voting *** combining the normalization with the light field descriptor,the Horizontal Light Descriptor is introduced to measure the shape similarity among the normalized urban *** color descriptors are used to represent the color information of the urban *** two types of descriptors are joined to search 3D urban models similar to the query *** results have shown the effectiveness of our approach.

关键词： 3D urban models shape descriptor color descriptor model retrieval

地震荷载作用下深厚饱和砂土中桩动力特性试验研究

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路基工程 2023年第1期 99-106页

作者：郝宇杰郭竟语王玉珏梁春明马建林西南交通大学土木工程学院成都610031 中铁二院工程集团有限责任公司成都610031

以某工程为依托,进行1∶20比例缩尺2×1桩基模型振动台试验,输入与当地地震设计反应谱接近的3种地震波,研究深厚饱和砂土场地条件下砂土-桩基-结构动力相互作用响应规律。试验再现液化宏观现象,研究表明:深厚饱和砂土场地对地震波高频... 详细信息

以某工程为依托,进行1∶20比例缩尺2×1桩基模型振动台试验,输入与当地地震设计反应谱接近的3种地震波,研究深厚饱和砂土场地条件下砂土-桩基-结构动力相互作用响应规律。试验再现液化宏观现象,研究表明:深厚饱和砂土场地对地震波高频部分过滤作用显著;随着地震动强度增大,场地液化程度提高,结构水平运动由高频向低频移动,频带范围变宽。同时,上部结构水平运动放大系数由4.56降低至2.75,但该效应对承台不明显;上部结构及承台在加载过程中相互影响,上部结构对承台的影响较大;砂层中部(距土体表面8D处)桩身弯矩相对于桩顶弯矩对输入地震波峰值加速度敏感度更高,随砂层液化程度增大而显著增大。

关键词：深厚饱和砂土层桩基础桥梁地震荷载作用砂土液化土-桩-结构相互作用桩身弯矩

Influence of zinc state on the catalyst properties of Zn/HZSM-5 zeolite in 1-hexene aromatization and cyclohexane dehydrogenation

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Chinese Journal of Chemical Engineering 2022年第3期35卷 124-134页

作者： Di Gao Yibo Zhi Liyuan Cao liang Zhao Jinsen Gao chunming Xu Mingzhi Ma Pengfei Hao State Key Laboratory of Heavy Oil Processing China University of Petroleum(Beijing)Beijing 102249China Hebei Jingzhi Technology Company Limited Cangzhou 061000China

Rational design of Zn-containing HZSM-5 zeolite(Zn/HZSM-5)with high reactivity and excellent aromatization performance for olefin aromatization is crucially *** develop a new and uncomplicated method to synthesize Zn/HZSM-5(IMX/Z5)with superior aromatization performance in the *** to incipient wetness impregnation(IMP/Z5)and mechanical mixing(MIX/Z5),the asprepared IMX/Z5 presents a higher amount of surface ZnOH^(+)species(2.87%)while keeping identical bulk zinc *** a result,more surface ZnOH^(+)favor both the aromatization of 1-hexene and cyclohexane *** the two olefin aromatization pathways(hydrogen transfer and dehydrogenation),it is the first time found both the hydrogen transfer ability and the dehydrogenation ability increase linearly with the amount of surface ZnOH^(+)species while keeping identical bulk zinc *** believe that the linear relationships are essential to design next generation olefin aromatization catalysts.

关键词： Zinc state Catalyst Catalysis Hydrogen transfer Dehydrogenation Moleclar sieves

Coupled Cu doping and Z-scheme heterojunction for synergistically enhanced tetracycline photodegradation

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Nano Research 2024年第7期17卷 5937-5948页

作者： Huidong Shen chunming Yang Song Hong Leiduan Hao liang Xu Alex W.Robertson Zhenyu Sun Country State Key Laboratory of Organic-Inorganic Composites College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Shaanxi Key Laboratory of Chemical Reaction Engineering College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China Department of Physics University of WarwickCoventry CV 47ALUK

Semiconductor-based photocatalysis by utilizing solar energy for sustainable organic pollutant elimination has been a promising tactic to alleviate environmental ***,the development of robust and efficient photocatalysts to degrade organic pollutants still faces major challenges because of insufficient charge *** we design and fabricate a heterojunction consisting of copper,carbon-modified TiO_(2),and sulfur-doped g-C_(3)N_(4)nanosheets(i.e.,S-C_(3)N_(4)/Cu/C-TiO_(2)).The heterostructure affords a remarkable synergistic photocatalysis for tetracycline hydrochloride degradation,achieving an 82.6%removal efficiency within 30 min under visible light irradiation,about 15.4 and 7.3 times higher than that of S-C_(3)N_(4)and C-TiO_(2),*** superior performance is attributed to the synergy between Cu doping and the Z-scheme heterojunction,which not only enhances the interfacial electric field effect,facilitating charge separation,but also boosts the redox *** charge carrier transfer between Cu/C-TiO_(2)and S-C_(3)N_(4)follows a Z-scheme,as verified by trapping experiments,electron spin-resonance spectroscopy,and density functional theory ***,the tetracycline hydrochloride degradation pathways are enunciated by liquid chromatograph mass spectrometry *** work provides an effective approach for constructing high-performance photocatalysts that have potential in environmental remediation.

关键词： photocatalysis Cu doping Z-scheme heterojunction electrons and holes separation tetracycline degradation