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MSE分子筛的孔道调控和酸量对催化裂解正庚烷制低碳烯烃性能的影响

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石油学报(石油加工) 2025年第1期41卷 1-13页

作者：范军杨诗棋濮鑫叶磊朱卡克纪晔刘纪昌华东理工大学化工学院上海200237 中国石油天然气股份有限公司中国石油规划总院北京100083 石河子大学新疆兵团化工绿色过程重点实验室新疆石河子832003

多级孔化和调控酸量是提高MSE分子筛催化裂解性能的有效途径。通过珠磨-重结晶法合成了具有纳米尺度、窄粒径分布的多级孔UZM-35分子筛,探讨了制备过程中珠磨时间和重结晶时间等因素对分子筛结构的影响,并通过硝酸溶液脱铝降低MSE分子... 详细信息

多级孔化和调控酸量是提高MSE分子筛催化裂解性能的有效途径。通过珠磨-重结晶法合成了具有纳米尺度、窄粒径分布的多级孔UZM-35分子筛,探讨了制备过程中珠磨时间和重结晶时间等因素对分子筛结构的影响,并通过硝酸溶液脱铝降低MSE分子筛的酸量。采用X-射线衍射(XRD)、扫描电子显微镜(SEM)、氮气物理吸附-脱附、固体核磁、氨气程序升温脱附(NH 3-TPD)和吡啶红外(Py-IR)等手段对分子筛的形貌、孔道结构和酸性质进行表征测定。以正庚烷催化裂解制备低碳烯烃为探针反应,对MSE分子筛进行性能评价,结果表明:通过引入多级孔结构和降低酸量促进MSE孔道中的单分子裂解反应,抑制氢转移副反应,使乙烯+丙烯收率提高,失活速率降低。在反应温度913 K、质量空速5 h-1的条件下,脱铝多级孔UZM-35分子筛的裂化机理比达到73.5,氢转移系数低至0.11;乙烯+丙烯收率为48.6%,比初始UZM-35分子筛提高了6.1%;反应10 h的失活率为4.1%,比初始UZM-35分子筛降低了14.3%。

关键词：低碳烯烃催化裂解多级孔 UZM-35分子筛珠磨-重结晶

Insight into the Role of Isolated Gold Atoms-Ceria Conjunction in Catalyzing the Water-Gas Shift Reaction

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Chinese Journal of Chemistry 2024年第6期42卷 636-644页

作者： xin-pu Fu Hui-Zhao Wei-Wei Wang Chun-Jiang Jia Key Laboratory for Colloid and Interface Chemistry Key Laboratory of Special Aggregated MaterialsSchool of Chemistry and Chemical EngineeringShandong UniversityJinanShandong250100 China

As the promising catalysts for the water-gas shift(WGS)reaction,the activity of Au-CeO_(2) composites is susceptible to the aggregation size and electronic state of Au *** reports were extensively focused on the discrepancy between nonmetallic Au and metallic Au nanoparticles,whereas the understanding of the authentic role of the isolated Au atoms was ***,we investigated the catalytic behavior and structural information over two types of Au/CeO_(2) catalysts,in which the predominant conjunctions were isolated Au1-CeO_(2) and Aun-CeO_(2),*** on comprehensive characterizations,particularly by in-situ Raman and in-situ DRIFTS,we found that the isolated Au atoms were responsible for enhancing the reducibility of the CeO_(2) *** CO adsorption ability on the isolated Au sites was significantly inferior to clustered Au atoms,especially at relatively high temperatures(>200°C).As a result,the boosted O vacancy on the isolated Au1-CeO_(2) conjunctions could improve the H2O activation ability for the Au-CeO_(2) catalysts and demonstrate a comparable activity to the clustered Aun-CeO_(2) *** work might deepen understanding of the catalytic function for the isolated Au1 site within Au/CeO_(2) systems while catalyzing the WGS reaction.

关键词： Isolated Au atoms Ceria-based catalysts Water-gas shift reaction Defect Adsorption

A FRACTURE-ENERGY-BASED ELASTO-SOFTENING-PLASTIC CONSTITUTIVE MODEL FOR JOINTS OF GEOMATERIALS

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Applied Mathematics and Mechanics(English Edition) 2002年第9期23卷 1097-1104页

作者： SHEN xin-pu(沈新普) SHEN Guo-xiao(沈国晓) Department of Mechanics Northeastern University Shenyang110004 P R China Department of Applied Sciences Taiyuan Institute of Heavy Machine Taiyuan030024 P R China

On the basis of plasticity and fracture mechanics for quasi-brittle materials, this article presented a constitutive model for gradual softening behavior of joints of geomaterials. Corresponding numerical tests are carried out at the local level. Characteristics of the model proposed are 1) plastic softening and dilatancy behavior are directly related to the fracture process of joint, and much less material and model parameters are required compared with those proposed by references; 2) the process of decohesion coupled with frictional sliding at both micro-scale and macro-scale is described.

关键词： interface crack quasi-brittle fracture joint element dilatancy non-associated plasticity

Tribological properties of high velocity arc sprayed Fe-Al based composite coatings at elevated temperature

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中国有色金属学会会刊：英文版 2004年第z1期14卷 379-382页

作者： ZHANG Wei ZHANG Shu XU Wei-pu ZU Zi-xin XU Bin-shi National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China

Fe-Al based intermetallic composite coatings were in-situ synthesized using Fe-Al/Cr3C2 or Fe-Al/WC cored wires and high velocity are spraying (HVAS) technology. The tribological properties of the Fe-Al based intermetallic composite coatings were investigated using a ball-on-disc tribotester from room temperature to 650 ℃. The results show that the coatings have relatively high bond strength and micro-hardness. The tribological properties of Fe-Al/Cr3C2 and Fe-Al/WC composite coatings were further analyzed and compared. Low and stable wear rates of the Fe-Al based intermetallic composite coatings were indicated from room temperature to 650 ℃. The excellent wear resistance of the composite coatings in high temperature was discussed.

关键词： high velocity arc spray (HVAS) composite coating tribology

Adaptive hp finite element method for fluorescence molecular tomography with simplified spherical harmonics approximation

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Journal of Innovative Optical Health Sciences 2014年第2期7卷 70-81页

作者： Hongbo Guo Yuqing Hou Xiaowei He Jingjing Yu Jingxing Cheng xin pu School of Information Sciences and Technology Northuest University Xi'an710069P.R.China School of Physics and Information Technology Shaanxi Normal University Xi'an710062P.R.China

Recently,the simplified spherical harmonics equations(SP)model has at tracted much att entionin modeling the light propagation in small tissue ggeometriesat visible and near-infrared wave-leng *** this paper,we report an eficient numerical method for fluorescence moleeular tom-ography(FMT)that combines the advantage of SP model and adaptive hp finite elementmethod(hp-FEM).For purposes of comparison,hp-FEM and h-FEM are,respectively applied tothe reconstruction pro cess with diffusion approximation and SPs *** experiments on a 3D digital mouse atlas and physical experiments on a phantom are designed to evaluate thereconstruction methods in terms of the location and the reconstructed fluorescent *** results demonstrate that hp-FEM with SPy model,yield more accurate results thanh-FEM with difusion approximation model *** phantom experiments show the potentialand feasibility of the proposed approach in FMT applications.

关键词： Fluorescence molecular tomog maphy simplified spherical harmonics equations reconstruction adaptive finite element method.

A novel process for comprehensive utilization of vanadium slag

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International Journal of Minerals,Metallurgy and Materials 2016年第2期23卷 156-160页

作者： Li-ying Liu Tao Du Wen-jun Tan xin-pu Zhang Fan Yang School of Metallurgy Northeastern University

Traditional processes for treating vanadium slag generate a huge volume of solid residue and a large amount of harmful gas,which cause serious environmental *** this study,a new process for the comprehensive utilization of vanadium slag was proposed,wherein zeolite A and a V2O5/TiO2 system were *** structural properties of the as-synthesized zeolite A and the V2O5/TiO2system were characterized using various experimental techniques,including X-ray diffraction,X-ray fluorescence,scanning electron microscopy,and infrared *** results reveal that zeolite A and the V2O5/TiO2 system are successfully obtained with high *** results of gas adsorption measurements indicate that the prepared zeolite A exhibits high selectivity for CO2 over N2 and is a candidate material for CO2 capture from flue-gas streams.

关键词： vanadium slag zeolite waste utilization structural properties

A new phenylethanoid glycoside from Isodon sculponeatus

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Chinese Chemical Letters 2011年第8期22卷 961-963页

作者： Li Mei Li Jian xin pu Wei Lie Xiao Han Dong Sun Scientific Research Center Chengdu Medical College Chengdu 610083 China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China

A new phenylethanoid glycoside,seulponisidc（1） was isolated from the aerial parts of Isodon sculponeatus（Vaniot） Kudo, along with six known compounds martynoside（2）,verbascoside（3）,（＋）-hydroxypinoresinol-8-O- β-D-glucoside（4）,cedrusin（5）, 7-megastigmene-3S,5R,6R,7E,9S-tetrol（6） and 4-oxo- β-ionol- β-D-glucopyranoside（7）.Their chemical structures were elucidated from physieochemical data and by acidic hydrolysis.

关键词： Isodon sculponeatus(Vaniot) Kudo Labiatae Phenylethanoid glycoside Sculponiside

Chemical constituents from Schisandra sphenanthera

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Chinese Chemical Letters 2008年第6期19卷 696-698页

作者： Rong Tao Li Zhi Ying Weng Jian xin pu Han Dong Sun State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China The College of Life Sciences and Technology Kunming University of Science and Technology 253 Xuehu Road Kunming 650093 China

The chemical constituents of the stems of Schisandra sphenanthera are described for the first time. This investigation has resulted in the isolation of a new phenolic glycoside （1）, along with seven known compounds.... 详细信息

关键词： Schisandra sphenanthera Phenolic glycoside 4,6-Dihydroxyphenyl-l-butanone-2-β-D-O-glucopyranoside

A New Ecdysteroid from Rhaponticum uniflorum

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Chinese Chemical Letters 2001年第9期12卷 797-798页

作者： Yong Hong ZHANG xin pu LI Zhi Gang LU Han Qing WANG Lanzhou Institute of Chemical Physics Chinese Academy of SciencesLanzhou 730000 Lanzhou Institute of Animal Science and Animal Medicine Lanzhou 730050

A new phytoecdysteroid was isolated from the root of Rhaponticum uniflorum. Its structure has been shown to be 2, 3, 20, 22-diacetonide ajugasterone.

关键词： Rhaponticum uniflorum compositae 2, 3, 20, 22-diacetonide ajugasterone