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Preparation of Alumina Binder-Added PtSnNa/AlSBA-15 Catalyst for Propane Dehydrogenation

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China Petroleum Processing & Petrochemical Technology 2013年第1期15卷 25-31页

作者： Zhang Peixin zhou yuming Duan Yongzheng Zhang Yiwei Sheng Xiaoli School of Chemistry and Chemical Engineering Southeast University Geological Survey of Jiangsu Province

Abstract： The present article compares the propane dehydrogenation performance of alumina binder-added PtSnNa/ A1SBA-15 catalysts prepared via three different procedures in comparison with the performance of a binder-free PtSnNa/ AISBA-15 catalyst. All these catalysts have been investigated by reaction tests and some physico-chemical characterizations such as BET, H2 chemisorption, catalytic grain crushing strength, NHa-TPD and TPO analyses. Test results showed that the addition of alumina binder could enhance the mechanical strength of catalyst evidently. Moreover, the different preparation procedures not only modified the characteristics of both acid and metal functions but also affected the coke deposition on the catalysts. Among these catalysts studied, the catalyst prepared by impregnation followed by the agglomeration of alumi- na binder had exhibited the highest catalytic activity and stability compared with other catalyst samples undergoing different preparation procedures. The possible reason may be attributed to the highest metallic dispersion and the strong interactions among Pt, Sn and the support.

关键词： A1SBA-15 binder preparation procedure propane dehydrogenation alumina.

Influence of Alumina Content on Catalytic Performance of PtSn/Al_2O_3/SBA-15 Catalysts for Propane Dehydrogenation

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China Petroleum Processing & Petrochemical Technology 2012年第4期14卷 9-16页

作者： Zhang Peixin zhou yuming Duan Yongzheng Zhang Yiwei Sheng Xiaoli School of Chemistry and Chemical Engineering Southeast University Geological Survey of Jiangsu Province

The alumina-modified SBA-15 （A12OJSBA-15） zeolite was prepared in a non-aqueous system by using toluene as the solvent, and was used to support the PtSn-based catalyst for propane dehydrogenation. The BET surface area mea- surements, hydrogen chemisorption, FT-IR spectroscopy, NH3-TPD, XPS and TPO techniques were used to characterize the catalysts. Test results showed that the addition of alumina not only could modify the acid function of the support but also the structure of the metallic phase, thus affecting their catalytic properties. Among these catalysts studied, the PtSn/AI203 （5%）/ SBA-15 catalyst exhibited a best catalytic performance in terms of propane conversion and selectivity to propene. The high catalytic performance might be attributed to the relatively good Pt metal dispersion and/or the strong interaction between Pt and Sn species.

关键词： SBA- 15 A1203 propane dehydrogenation propene Pt

Propane Dehydrogenation on PtSnNa/AlSBA-15 Catalyst:Influence of Tin as a Promoter

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China Petroleum Processing & Petrochemical Technology 2012年第1期14卷 37-45页

作者： Duan Yongzheng zhou yuming Zhang Yiwei Sheng Xiaoli Xue Mengwei School of Chemistry and Chemical Engineering Southeast UniversityNanjing 211189 Biochemical and Environmental Engineering College Nanjing Xiaozhuang UniversityNanjing 211171

PtSnNa/AlSBA-15 catalysts with different amounts of Sn were prepared for propane *** catalysts were characterized by XRF,BET,H2 chemisorption,NH3-TPD,H2-TPR,and TPO *** results indicated that the presence of tin not only modified the acid function and the interfacial character between metal and support,but also reduced the coke deposition *** these catalysts investigated thereby,the PtSn(0.7%)Na/AlSBA-15 catalyst had the best catalytic performance in terms of propane conversion and *** the continuous addition of Sn,more amounts of Sn0 species appeared,which was unfavorable to the *** PtSn(0.7%)Na/AlSBA-15 catalyst was parametrically characterized in order to obtain necessary information to integrate the process operating conditions.A weight hourly space velocity of 3 h-1,a reaction temperature of 610 ℃ and a H2/C3H8 molar ratio of 0.25 were found to be optimum conditions for achieving a higher dehydrogenation activity of the catalyst.

关键词： propane dehydrogenation PtSnNa/A1SBA-15 catalyst

大气压脉冲微波Ar/N_(2)等离子体射流的时空特性研究

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中国科学：物理学、力学、天文学 2024年第3期54卷 158-171页

作者：陈兆权王伟业陈思乐王超徐笑娟王兵周郁明卢新培安徽工业大学安徽省高校电力电子与运动控制重点实验室马鞍山243032 华中科技大学强电磁工程与新技术国家重点实验室武汉430074

在空气环境中,很难形成特定形貌的微波等离子体射流.本文构建了双气体通道同轴谐振放电装置,在空气环境中产生了脉冲微波Ar/N_(2)双层等离子体射流.实验测量了Ar/N_(2)等离子体射流电离发展的时空演变过程:(1)使用高速相机测量等离子体... 详细信息

在空气环境中,很难形成特定形貌的微波等离子体射流.本文构建了双气体通道同轴谐振放电装置,在空气环境中产生了脉冲微波Ar/N_(2)双层等离子体射流.实验测量了Ar/N_(2)等离子体射流电离发展的时空演变过程:(1)使用高速相机测量等离子体射流形貌的瞬态变化,发现电离的初始阶段和结束阶段存在光辐射增强的放电影像;(2)使用瑞利散射装置测量等离子体射流的电子密度,发现电子密度值达到10^(21)m^(-3)数量级,且在脉冲微波的上升沿和下降沿各有一次电离波峰;(3)使用单色仪测量特定波长段光谱的瞬态变化,追踪N_(2)^(+)谱线从首次出现到稳定发展、直至最后衰减消失的过程.结合实验测量结果和电磁仿真分析,发现脉冲微波的上升沿和下降沿各有一次增强电离过程,揭示了脉冲微波Ar/N_(2)双层等离子体射流的特殊放电形貌是时空局域增强电离致使.

关键词：微波放电电离机理等离子体射流电磁模拟

Effect of Mischmetal Addition on Catalytic Performance of PtSnNa/ZSM-5 for Propane Dehydrogenation

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China Petroleum Processing & Petrochemical Technology 2011年第3期13卷 47-52页

作者： Xue Mengwei zhou yuming Huang Li Zhang Yiwei Duan Yongzheng Sheng Xiaoli School of Chemistry and Chemical Engineering Southeast University Nanjing 211189 School of Biochemical and Environmental Engineering Nanjing Xiaozhuang University

The influence of mischmetal addition on physicochcmical properties of PtSnNa/ZSM-5 catalyst was studied by means of XRF, H2 chemisorption, XRD, TPR, NH3-TPD and TPO techniques. The results showed that the presence of mischmetal had an obvious impact on the catalytic performance of the PtSnNa/ZSM-5 catalyst. A suitable content of mischmetal not only could enhance the interactions between Pt species and the support, but also inhibit the formation of coke during the reaction, thus improving the catalytic activity and stability. In our experiments, when the content of mischmetal was 3m%, the catalyst exhibited best catalytic performance. However, the continuous addition of mischmetal could promote the reduction of Sn species to metallic tin, which was disadvantageous to the reaction.

关键词： mischmetal propane dehydrogenation PtSnNa/ZSM-5 catalyst

Spider web-like carbonized bacterial cellulose/MoSe_(2) nanocomposite with enhanced microwave attenuation performance and tunable absorption bands

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Nano Research 2021年第3期14卷 738-746页

作者： Zhengjian Xu Man He yuming zhou Shuangxi Nie Yongjuan Wang Yao Huo Yifan Kang Ruili Wang Ran Xu Hao Peng Xi Chen Jiangsu Optoelectronic Functional Materials and Engineering Laboratory School of Chemistry and Chemical EngineeringSoutheast UniversityNanjing211189China Guangxi Key Laboratory of Clean Pulp&Papermaking and Pollution Control College of Light Industry and Food EngineeringGuangxi UniversityNanning530004China

It is essential to manufacture microwave absorbers with strong absorption as well as tunable absorption bands at a low filler ***,it remains challenging for pure biomass material to reach this goal without loading other ***_(2),as a transition metal chalcogenide with semiconductor properties,has emerged as a potential microwave absorber ***,bacterial cellulose(BC)-derived carbon nanofibers/MoSe_(2) nanocomposite was fabricated and phosphoric acid was used to dope phosphorus in BC,in which MoSe_(2) microspheres were dropped on the BC network like a dew-covered spider *** unique network structure enhances conductive loss and multiple reflections of the incident *** collocation of BC and MoSe_(2) is helpful to impedance match and introduces interfacial/dipolar polarization loss;moreover,the P-doping of BC helps to tune the absorption ***,the optimal reflection loss of undoped one reaches−53.33 dB with only 20 wt.%filler content,whose main absorption peaks focus on ***,after the P-doping of BC,the main absorption peaks move to Ku-band and the optimal reflection loss gets stronger(−66.84 dB)with the same filler *** absorption and tunable absorption bands can be realized,and thus wide frequency range is *** work is expected to enlighten future exploration of biomass carbon materials on high-performance microwave absorption materials.

关键词： bacterial cellulose MoSe_(2) network structure P-doped carbon tunable absorption band

浅析无仪器主机如何实现可控震源Smart LF技术

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物探装备 2024年第1期34卷 13-15,25页

作者：孙军和周玉明郭俊超方涛赵利中中国石油集团东方地球物理勘探有限责任公司国际勘探事业部河北涿州072750 中国石油集团东方地球物理勘探有限责任公司辽河物探分公司中国石油集团东方地球物理勘探有限责任公司装备服务中心

Sercel公司推出可控震源低频去谐波功能简称Smart LF,该功能能够显著降低可控震源在低频段的畸变,需要匹配508XT仪器主机激活才能使用,适用于VE464电控箱体的4.0及以上版本。可是随着节点设备的推广应用,不再需要仪器主机就可以独立作业... 详细信息

Sercel公司推出可控震源低频去谐波功能简称Smart LF,该功能能够显著降低可控震源在低频段的畸变,需要匹配508XT仪器主机激活才能使用,适用于VE464电控箱体的4.0及以上版本。可是随着节点设备的推广应用,不再需要仪器主机就可以独立作业,在没有508XT仪器主机的情况下该如何实现Smart LF功能,SMA软件完美移植了508XT仪器主机管理可控震源的功能,能够在无仪器主机情况下激活Smart LF,从而实现Smart LF的独立操作和使用。

关键词：低频去谐波功能畸变仪器主机可控震源管理

Emotional and Behavioral Problems of Left-Behind Children in Impoverished Rural China:A Comparative Cross-Sectional Study of First Grade Junior High School

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International Journal of Mental Health Promotion 2021年第1期23卷 1-13页

作者： yuming zhou Chunxia Zhao Fan He Xiaobo Tian Yi Zheng Jing Sun Beijing Anding Hospital Capital Medical UniversityThe National Clinical Research Center for Mental DisordersBeijing Key Laboratory of Mental DisordersBeijing Institute for Brain DisordersBeijing100088China United Nations Children’s Fund(UNICEF China Office) Beijing100600China School of Medicine Griffith UniversityQueensland4222Australia

Objective:To investigate the prevalence of emotional and behavioral problems and related factors of left-behind children in impoverished rural China(mainly in thefirst grade of junior high school).Methods:A cross-sectional survey of rural households in 27 poverty-stricken counties in 12 provinces across China was conducted using the Strengths and Difficulties Questionnaire(SDQ).Results:The prevalence of emotional and behavioral problems in left-behind children was 11.7%,and that of non-left-behind children was 8.9%.There was statistical difference between the two groups(P<0.01).There are no differences between the two groups in terms of the various factors of *** incidence of insomnia in the left-behind group was 58.3%,which was higher than that in the non-left-behind group 50.9%(P<0.01);loneliness(62.1%vs.51.8%,P<0.01);running away from home(23.1%vs.18.8%,P<0.01),and self-injury behavior(16.8%vs.12.2%,P<0.01).Left-behind children are more likely to have negative psychological feelings including insomnia,loneliness,self-injury,and run away from *** also experienced more bullying including maliciously teased by peers,intentionally excluded or isolated,physically threatened or *** of these factors are associated with their abnormal emotional and behavioural ***:The incidence of emotional and behavioral problems of left-behind children in rural areas in poverty-stricken areas is significantly higher than that of non-left-behind children;Logistic regression analysis showed that bullying behavior and abnormal psychological characteristics are significantly associated with left-behind adolescents abnormal emotional and behavioral development.

关键词： Rural areas left-behind children emotional and behavioral problems incidence related factors

Propane Dehydrogenation over PtSnNa Catalyst Supported on La-ZSM-5 Zeolite

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China Petroleum Processing & Petrochemical Technology 2010年第3期12卷 18-24页

作者： Huang Li zhou yuming Zhang Yiwei Li Qingning Tian Xiaoming (School of Chemistry and Chemical Engineering,Southeast University,Nanjing 211189) School of Chemistry and Chemical Engineering Southeast University Nanjing 211189 China

The La-ZSM-5 zeolite with different contents of La was synthesized by the hydrothermal method. The physico-chemical properties of the materials were studied. The results of FT-IR analyses indicated that La might be incorporated into the framework of ZSM-5 zeolite. The NH3-TPD analyses showed that the amount of weak acid sites of the zeolite decreased with a continuously increasing La content. Afterwards, the La-ZSM-5 zeolite was used as the support of PtSnNa catalyst for propane dehydrogenation. The test results revealed that the utilization of La- ZSM-5 zeolite could achieve a high propene conversion, and effectively inhibit the coke formation on the catalyst surface. When the content of La was 0.16%, the catalytic activity and stability of the catalyst got the best of its performance. Besides, the PtSnNa/La （0.16%）-ZSM-5 catalyst is more stable than the conventional PtSnNaLal ZSM-5 catalysts.

关键词： La-ZSM-5 propane dehydrogenation propene.