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Synthesis and characterization of BZSM-5 and its catalytic performance in the methanol to hydrocarbons reaction

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Chinese Journal of Chemical Engineering 2021年第7期34卷 196-203页

作者： Junhua Gao Keming Ji Hao Zhou jiayao xun Zenghou Liu Kan Zhang Ping Liu State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China

Five kinds of BZSM-5 molecular sieve with different Si/B ratio and a SiZSM-5 molecular sieve were prepared by hydrothermal synthesis method followed by acid exchange and *** samples were characterized by XRD,SEM,FT-IR,ICP,low temperature N_(2) physical adsorption and desorption,NH3-TPD and *** catalytic performance in the reaction of methanol to hydrocarbons was evaluated in the fixed bed *** with SiZSM-5,the amount and strength of Bronsted(B)acid were enhanced by introducing skeleton boron and the activity of the catalyst was greatly *** characterization and evaluation results indicated that the BZSM-5 catalyst synthesized from the gel of SiO_(2)/B2 O320 with Si/B ratio 74.48 had modest acidity strength,acid amount of 0.18 mmol NH3·g^(-1) and large mesopore volume of 0.23 cm3·g^(-1).The B acid ratio was higher and the acid strength of BZSM-5 was weaker than that of AIZSM-5,which could inhibit the deep coke formation and increase the activity stability.B-2 had the best lifetime which could reach 672 h under the same evaluation reaction conditions,due to the best matching of moderate acidity and good diffusion properties.

关键词： ZSM-5 Catalysis Methanol Hydrocarbons

The study of methanol aromatization on transition metal modified ZSM-5 catalyst

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Chinese Journal of Chemical Engineering 2018年第9期26卷 1949-1953页

作者： Keming Ji jiayao xun Ping Liu Qingwen Song Junhua Gao Kan Zhang Jingyuan Li State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences

In this article, transition metals of Cu, La and Zn were used as adjuvant to prepare modified HZSM-5 by impregnation method. The catalysts were characterized by XRD, BET, NH_3-TPD and Py-IR to reveal the microstructure and acid property. The catalysis performances of methanol aromatization of catalysts were investigated in a fixed-bed reactor. The results show that the strength and distribution of acid center of these catalysts are significantly influenced by the species of transition metal. There are more mediate strong Lewis acid center in Zn modified HZSM-5 catalyst and therefore exhibits higher selectivity to aromatic, benzene, toluene and xylenes in the MTA reaction..

关键词： Aromatization ZSM-5 Metal modified

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甲醛氧化催化剂及反应机理

化学进展 2021年第9期33卷 1560-1570页

作者：苏原吉可明荀家瑶赵亮张侃刘平中国石油大学(北京)重质油国家重点实验室北京102249 中国科学院山西煤炭化学研究所煤转化国家重点实验室太原030001

甲醛具有致畸和致癌性,是主要的室内污染物。催化氧化法甲醛转化效率高,没有二次污染,相关研究日益受到关注。本文详细介绍了贵金属和非贵金属两类主要的甲醛氧化催化剂,探讨了活性组分、载体、催化剂助剂等催化剂组成对于其理化性质和... 详细信息

甲醛具有致畸和致癌性,是主要的室内污染物。催化氧化法甲醛转化效率高,没有二次污染,相关研究日益受到关注。本文详细介绍了贵金属和非贵金属两类主要的甲醛氧化催化剂,探讨了活性组分、载体、催化剂助剂等催化剂组成对于其理化性质和反应性能的影响规律,讨论了制备方法、反应物中的水含量等因素对于催化反应的影响,分析了催化剂失活的主要因素。研究表明,催化剂表面活性氧、表面羟基、氧空位数量以及对反应物的吸脱附和存储能力是影响催化活性的关键因素。贵金属催化剂,特别是Pt催化剂具有较好的催化性能,可在较低温度实现甲醛充分转化;非贵金属催化剂具有可变价态,通过催化剂的合理设计可以具有足够的催化活性,其原料资源丰富,价廉易得,应用前景广阔。

关键词：甲醛催化氧化贵金属催化剂催化机理失活

Catalytic oxidation of low concentration formaldehyde over Pt/TiO₂ catalyst

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Synthesis and characterization of BZSM-5 and its catalytic performance in the methanol to hydrocarbons reaction

Chinese Journal of Chemical Engineering 2021年第1期

作者： Yuan Su Keming Ji jiayao xun Kan Zhang Ping Liu Liang Zhao

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The Historical Fate of Lu xun in Today＇s China

Chinese Journal of Chemical Engineering 2021年第7期

作者： Junhua Gao Keming Ji Hao Zhou jiayao xun Zenghou Liu Kan Zhang Ping Liu

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Frontiers of Literary Studies in China-Selected Publications from Chinese Universities 2013年第4期7卷 529-540页

作者： Lu xun His Legacy Institute of Chinese Studies Delhi lndia 15-18 November 2012

＂The historical fate of Lu xun in today＇s China＂ is an enormous topic, and a discussion of this question can also encompass important questions of Chinese society, thought, and culture. I have not performed special...

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RESEARCH ON TURBULENT FLOW WITHIN THE VORTEX PUMP

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Journal of Hydrodynamics 2004年第6期16卷 701-707页

作者： CHENHong-xun ShanghaiInstituteofAppliedMathematicsandMechanics ShanghaiUniversityShanghai200072China

Based on the standard k-ε turbulence model and the RANS equations, thefinite volume method and the SIMPLE algorithm were adopted to carry out the three-dimensionalviscous numerical simulation of the internal flow within a vortex pump in double reference *** to the results of numerical simulation, the internal flow in the vortex pump was analyzed,and the calculated results of blade surface pressure of the impeller were compared withexperimental results. The maximum relative error is 6.6% between calculated value and experimentalvalue of the pump head under operation conditions.

关键词： vortex pump internal flow turbulence

Application of Self-inhaling Internal Cooling Wheel in Vertical Surface Grinding

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Chinese Journal of Mechanical Engineering 2014年第1期27卷 86-91页

作者： LI xun School of Mechanical Engineering and Automation Beihang University

There is less research on vertical sculptured grinding technology. Especially in high vertical surface grinding process with the cup abrasive wheel, the thermal damage is prone to happen and undermine the grinding surface integrity. This problem limits to improve the grinding efficiency and the grinding ratio greatly. Through the analysis of vertical surface grinding process and features in depth, this paper revealed the inherent mechanism of higher grinding temperature in the process of vertical sculptured grinding using the cup wheel. Based on the previous research achievements, the grinding experiments on TC4 （Ti-6A1-4V） and GH4169 are carried out utilizing the self-inhaling internal cooling wheel. The experimental results show that the self-inhaling internal cooling wheel can efficiently reduce the grinding surface temperature. Moreover, the inherent mechanism of reducing the grinding temperature using the internal cooling method is revealed. Meanwhile, under the same grinding conditions, the grinding ratio during the experiments on GH4169 using self-inhaling internal cooling method is about 3 times as high as using conventional external cooling method. And the grinding forces can be reduced by about 20%. This research revealed the inherent mechanism of higher grinding temperature in the process of vertical sculptured grinding using the cup wheel, which provides theoretical basis for the design and application of self-inhaling internal cooling wheel. At the same time, an efficient and non-invasive surface grinding method of TC4 and GH4169 is presented.

关键词： vertical grinding intemal cooling grinding temperature grinding ratio

Biotechnology smart control over stem cell fate commitment at nanoscale

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Science China Materials 2018年第3期61卷 435-436页

作者： xun Wang Department of Chemistry Tsinghua University

In the landscape of desirable stem-cell-based regeneration,the fate of cell is directed by orchestrated dialog between nanoscale subcellular receptors and biointerfacial niches^([1]).This bottom-up development manner has inspired a great many nanogeometric^([2])and nanotopographic^([3])material-based biointerfaces promising for regenerative *** previous studies shed

关键词： Biotechnology smart control over stem cell fate commitment at nanoscale