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新型炭材料（中英文） 2024年第4期39卷 633-644页

作者： ZHANG Jia-ping SU Xiao-xuan LI Xin-gang WANG Run-ning FU qian-gang Shaanxi Key Laboratory of Fiber Reinforced Light Composite Materials Northwestern Polytechnical UniversityXi’an 710072China

The development of advanced aircraft relies on high performance thermal-structural materials,and carbon/carbon com-posites(C/C)composited with ultrahigh-temperature ceramics are ideal ***,the traditional routes of compositing are either inefficient and expensive or lead to a non-uniform distribution of ceramics in the *** with the traditional C/C-ZrC-SiC composites prepared by the reactive melt infiltration of ZrSi_(2),C/C-ZrB_(2)-ZrC-SiC composites prepared by the vacuum infiltration of ZrB_(2) combined with reactive melt infiltration have the higher content and more uniform distribution of the introduced ceramic *** mass and linear ablation rates of the C/C-ZrB_(2)-ZrC-SiC composites were respectively 68.9%and 29.7%lower than those of C/C-ZrC-SiC composites prepared by reactive melt *** ablation performance was improved because the volatilization of B_(2)O_(3),removes some of the heat,and the more uniformly distributed ZrO_(2),that helps produce a ZrO2-SiO2 continu-ous protective layer,hinders oxygen infiltration and decreases ablation.

关键词： C/C composites ZrB_(2)-ZrC-SiC Vacuum filtration Reactive melt infiltration Ablation.

Kinetics insights into size effects of carbon nanotubes' growth and their supported platinum catalysts for 4,6-dinitroresorcinol hydrogenation

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CHINESE JOURNAL OF CHEMICAL ENGINEERING 2024年第8期72卷 133-140页

作者： Zhang, Yan Zhang, Xiangxue Sang, Keng Chen, Wenyao qian, gang Zhang, Jing Duan, Xuezhi Zhou, Xinggui Yuan, Weikang East China Univ Sci & Technol State Key Lab Chem Engn Shanghai 200237 Peoples R China

Size effects are a well-documented phenomenon in heterogeneous catalysis, typically attributed to alterations in geometric and electronic properties. In this study, we investigate the influence of catalyst size in the preparation of carbon nanotube (CNT) and the hydrogenation of 4,6-dinitroresorcinol (DNR) using Fe2O3 and Pt catalysts, respectively. Various Fe2O3/Al2O3 catalysts were synthesized for CNT growth through catalytic chemical vapor deposition. Our findings reveal a significant influence of Fe2O3 nanoparticle size on the structure and yield of CNT. Specifically, CNT produced with Fe2O3/Al2O3 containing 28% (mass) Fe loading exhibits abundant surface defects, an increased area for metal-particle immobilization, and a high carbon yield. This makes it a promising candidate for DNR hydrogenation. Utilizing this catalyst support, we further investigate the size effects of Pt nanoparticles on DNR hydrogenation. Larger Pt catalysts demonstrate a preference for 4,6-diaminoresorcinol generation at (1 0 0) sites, whereas smaller Pt catalysts are more susceptible to electronic properties. The kinetics insights obtained from this study have the potential to pave the way for the development of more efficient catalysts for both CNT synthesis and DNR hydrogenation. (c) 2024 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

关键词： Kinetics Size effects Catalytic hydrogenation Active site PHASE HYDROGENATION CINNAMALDEHYDE NITROBENZENE PRECURSOR FIBERS

Efficient continuous synthesis of 2-hydroxycarbazole and 4-hydroxycarbazole in a millimeter scale photoreactor

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Chinese Chemical Letters 2024年第4期35卷 399-403页

作者： Zhixiang Li Zhirong Yang Chang Yao Bin Wu gang qian Xuezhi Duan Xinggui Zhou Jing Zhang State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China

2-Hydroxycarbazole and 4-hydroxycarbazole are important chemicals with extensive applications in optoelectronic materials and pharmaceutical *** of the art yield of 2-hydroxycarbazole is~30%and the reaction time is typically in hours or ***,we developed a green route for the continuous and high-throughput synthesis of 2-hydroxycarbazole and 4-hydroxycarbazole via photochemical intramolecular cyclization of 3–hydroxy-2–chloro-diphenylamine using a self-designed millimeter scale photoreactor,which was designed based on sizing-up and numbering-up strategies for a decent liquid holdup(6.8 m L)and fabricated via femtosecond laser engraving *** photochemical synthesis was carried out continuously under the illumination of 365 nm UV-LED with dimethyl sulfoxide as solvent and potassium t-butoxide as *** was found that under optimized conditions a 2-hydroxycarbazole yield of 31.6%and a 4-hydroxycarbazole yield of 11.1%were obtained with a residence time of 1 *** to semibatch operations,the reaction time was shortened by 1–2 orders of *** a result,a throughput of 11.3 g/day 2-hydroxycarbazole and 4.0 g/day 4-hydroxycarbazole can be achieved from the *** was proposed that the short reaction time and high product yield are resulted from higher photon transfer rates and more uniform photon distribution provided by the millimeter scale photoreactor,which enhances the reaction rates and mitigates overreaction.

关键词： Millimeter scale reactor 2-Hydroxycarbazole Photochemistry UV-LED Process intensification

Poisoning effect of polyvinyl chloride on the catalytic pyrolysis of mixed plastics over zeolites

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Science China Chemistry 2024年第7期67卷 2265-2273页

作者： Jiangchun Yuan Wenjie Wang Weixiao Sun Zhirong Yang Yueqiang Cao Wenyao Chen Xiaohu Ge gang qian Xiang Feng Xuezhi Duan Xinggui Zhou Kevin M.Van Geem Jing Zhang State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China Laboratory for Chemical Technology(LCT) Department of MaterialsTextiles and Chemical EngineeringFaculty of Engineering&ArchitectureGhent UniversityZwijnaarde B-9052Belgium State Key Lab of Heavy Oil Processing China University of PetroleumQingdao 266580China

Nowadays,the chemical recycling is applied for only 1%of total waste plastics,largely due to contaminants in plastic waste and difficulty in product *** the major contaminant,polyvinyl chloride(PVC)often forms corrosive hydrogen chloride(HCl)during the chemical recycling,which may cause severe catalyst deactivation and equipment ***,the investigation on catalytic pyrolysis(the major route for plastics chemical recycling)of the PVC containing mixed plastics has been rarely ***,catalytic co-pyrolysis of PVC and polyethylene(PE)was studied over an aromatization catalyst,Pt/ZSM-5,since the basic building block aromatics are desired products from plastics chemical *** poisoning effect of PVC vapor on the catalyst stability was explored by collective efforts of thorough product analysis and catalyst *** was found that the HCl evolving from PVC has an autocatalytic effect that promotes the scission of dehydrochlorinated PVC,resulting in the high yield of benzene and acetylene from *** the other hand,the presence of PVC suppressed the aromatics formation from PE,largely due to the poisoning effect of PVC-derived HCl on the Pt/*** deactivation is irreversible as evidenced by the decreased zeolite crystallinity and the loss of strong acid sites that are key to the aromatization,possibly due to the removal of framework Al upon the interaction with *** modification with octadecylphosphonic acid only slightly alleviated the PVC poisoning *** insights on the PVC poisoning of zeolite catalysts provided in this work may guide the process design of chemical recycling of PVC containing waste plastics.

关键词： polyvinyl chloride polyethylene zeolite aromatics deactivation

Kinetics insights into size effects of carbon nanotubes' growth and their supported platinum catalysts for 4,6-dinitroresorcinol hydrogenation

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Chinese Journal of Chemical Engineering 2024年第08期 133-140页

作者： Yan Zhang Xiangxue Zhang Keng Sang Wenyao Chen gang qian Jing Zhang Xuezhi Duan Xinggui Zhou Weikang Yuan State Key Laboratory of Chemical Engineering East China University of Science and Technology

Size effects are a well-documented phenomenon in heterogeneous catalysis, typically attributed to alterations in geometric and electronic properties. In this study, we investigate the influence of catalyst size in the preparation of carbon nanotube（CNT） and the hydrogenation of 4,6-dinitroresorcinol（DNR）using Fe2O3and Pt catalysts, respectively. Various Fe2O3/Al2O3catalysts were synthesized for CNT growth through catalytic chemical vapor deposition. Our findings reveal a significant influence of Fe2O3nanoparticle size on the structure and yield of CNT. Specifically, CNT produced with Fe2O3/Al2O3containing 28%（mass） Fe loading exhibits abundant surface defects, an increased area for metal-particle immobilization, and a high carbon yield. This makes it a promising candidate for DNR hydrogenation. Utilizing this catalyst support, we further investigate the size effects of Pt nanoparticles on DNR *** Pt catalysts demonstrate a preference for 4,6-diaminoresorcinol generation at（1 0 0） sites,whereas smaller Pt catalysts are more susceptible to electronic properties. The kinetics insights obtained from this study have the potential to pave the way for the development of more efficient catalysts for both CNT synthesis and DNR hydrogenation.

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芳构化法合成2,5-二羟基对苯二甲酸反应机理的密度泛函理论研究

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分子催化（中英文） 2024年第3期38卷 234-244,I0002页

作者：王先飞钱刚华东理工大学化工学院上海200237

采用密度泛函理论(DFT)计算,研究了由1,4-环己二酮-2,5-二甲酸二甲酯(DMSS)制备2,5-二羟基对苯二甲酸(DHTA)的反应机理.其中,采用IEFPCM溶剂模型着重计算了DMSS由酮式互变异构为烯醇式的溶剂效应,并探究了碘在催化DMSS烯醇式氧化芳构化... 详细信息

采用密度泛函理论(DFT)计算,研究了由1,4-环己二酮-2,5-二甲酸二甲酯(DMSS)制备2,5-二羟基对苯二甲酸(DHTA)的反应机理.其中,采用IEFPCM溶剂模型着重计算了DMSS由酮式互变异构为烯醇式的溶剂效应,并探究了碘在催化DMSS烯醇式氧化芳构化过程中的作用机制.计算结果表明,在溶剂分子的辅助下,DMSS酮-烯醇式互变异构反应的能垒显著降低;芳构化过程中,碘首先与过氧化氢反应生成活性物质次碘酸,其催化DMSS烯醇式发生碘代反应,并经过后续的消去和互变异构生成2,5-二羟基对苯二甲酸二甲酯(DMDHT),DMDHT进一步水解生成DHTA.同时,通过核磁共振氢谱测试验证了DMSS酮-烯醇式互变异构的溶剂效应;反应性能考评实验结果表明,相较于无催化剂,在碘的催化作用下,DMDHT产品的纯度和收率更高.

关键词： 2,5-二羟基对苯二甲酸 DFT 互变异构芳构化反应机理

基于[bmim][BF_(4)]相转移催化的氟代碳酸乙烯酯高效合成

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化工学报 2024年第4期75卷 1543-1551页

作者：蒋方涛钱刚周兴贵段学志张晶华东理工大学化工学院化学工程联合国家重点实验室上海200237

氟代碳酸乙烯酯(FEC)是锂电池电解液添加剂的重要组分之一,其工业制备方法主要为卤素交换法,即氯代碳酸乙烯酯(CEC)与氟化钾(KF)通过取代反应制备FEC。该工艺中,取代反应速率受限于KF相际传质速率,且CEC易发生消去反应生成碳酸亚乙烯酯... 详细信息

氟代碳酸乙烯酯(FEC)是锂电池电解液添加剂的重要组分之一,其工业制备方法主要为卤素交换法,即氯代碳酸乙烯酯(CEC)与氟化钾(KF)通过取代反应制备FEC。该工艺中,取代反应速率受限于KF相际传质速率,且CEC易发生消去反应生成碳酸亚乙烯酯副产物。针对上述问题,研究了相转移催化剂(PTC)结构对KF相际传质速率和CEC制FEC主副反应能垒的影响规律和调控机制。优化条件下,PTC为[bmim][BF_(4)](1-丁基-3-甲基咪唑四氟硼酸盐),溶剂为乙腈,反应温度为乙腈回流温度(81.6℃),n(KF)∶n(CEC)=2.5∶1,此时FEC收率高达91.94%(摩尔分数)。密度泛函理论计算表明,在乙腈中[bmim][BF_(4)]能与KF形成配合物,增加K+和F-的核间距并降低KF的溶解自由能,从而强化相际传质并降低取代反应能垒,实现CEC经KF取代高效制备FEC。

关键词：离子液体相转移催化配合物传质氟代碳酸乙烯酯密度泛函理论

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C2C模式的图书共享服务设计研究

图书馆研究 2024年第2期54卷 92-100页

作者：钱海钢广东省立中山图书馆广东广州510110

本研究是一种基于C2C模式的图书共享服务设计,旨在通过个人之间的图书共享来促进阅读的传播和流通;同时探讨提供该服务的具体实施方式和效果评估。分析了现有图书共享模式的主要形式及各自的优缺点,详细介绍了C2C模式的图书共享服务平... 详细信息

本研究是一种基于C2C模式的图书共享服务设计,旨在通过个人之间的图书共享来促进阅读的传播和流通;同时探讨提供该服务的具体实施方式和效果评估。分析了现有图书共享模式的主要形式及各自的优缺点,详细介绍了C2C模式的图书共享服务平台设计的构建要素,包括平台建设、用户激励和奖励机制、社交互动和推广活动、信任和安全机制、合作伙伴和资源整合,以及数据分析和个性化服务,指出该平台具有更加科学合理的效能优势,有助于全民阅读的推广。

关键词： C2C模式图书共享阅读推广

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氧化铝结构与表面性质调控及其催化甲醇脱水制二甲醚性能研究

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化工学报 2024年第7期75卷 2522-2532页

作者：罗莉陈文尧张晶钱刚周兴贵段学志华东理工大学化工学院化学工程联合国家重点实验室上海200237

二甲醚(DME)作为一种关键的化工原料,被广泛用于合成众多重要的化学品及能源产品。在工业生产中用于从甲醇制备DME的催化剂γ-Al_(2)O_(3)因其高效的催化性能而得到普遍应用。然而,γ-Al_(2)O_(3)的合成方法和制备条件对其催化性能有着... 详细信息

二甲醚(DME)作为一种关键的化工原料,被广泛用于合成众多重要的化学品及能源产品。在工业生产中用于从甲醇制备DME的催化剂γ-Al_(2)O_(3)因其高效的催化性能而得到普遍应用。然而,γ-Al_(2)O_(3)的合成方法和制备条件对其催化性能有着显著的影响。目前,对于工业上常用的γ-Al_(2)O_(3)合成条件如何影响其催化性能的系统研究仍然不足。特别是,作为影响催化性能的关键因素之一,酸性位点的性质尚未形成共识。通过调控双铝法成胶过程中母液的pH,成功合成了一系列具有不同孔道结构和酸性质的γ-Al_(2)O_(3)。实验结果表明,随着母液pH的增大,γ-Al_(2)O_(3)的比表面积、孔容和孔径均呈现减小趋势。同时,γ-Al_(2)O_(3)的弱酸量逐渐减小,而中强酸量呈现先增后减的趋势。进一步结合催化性能评估结果,发现中强酸数量与甲醇脱水性能密切相关。具有最高中强酸数量的γ-Al_(2)O_(3)表现出最高的DME产率,预示中强酸位点是γ-Al_(2)O_(3)催化甲醇脱水制备DME的主要活性中心。针对具有最优性能的γ-Al_(2)O_(3)开展动力学实验分析,得到甲醇脱水的反应级数为0.78,反应活化能为83.27 kJ/mol。研究可为甲醇脱水制备DME催化剂的设计提供指导,为进一步优化工业生产条件和提高催化效率夯实基础。

关键词：氧化铝甲醇脱水二甲醚酸性调控催化剂动力学

羊水原位培养法联合染色体微阵列分析在产前诊断中的应用

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临床检验杂志 2024年第2期42卷 85-89页

作者：向文秀钱罡怀化市妇幼保健院遗传科湖南怀化418099 浙江博圣生物技术股份有限公司杭州310012

目的评估羊水原位培养法联合染色体微阵列分析(CMA)技术在产前诊断检出胎儿染色体异常中的应用价值。方法回顾性分析2018年10月至2023年2月于怀化市妇幼保健院因不同产前诊断指征而行羊水穿刺术的3133例孕妇,比较羊水原位培养法和CMA法... 详细信息

目的评估羊水原位培养法联合染色体微阵列分析(CMA)技术在产前诊断检出胎儿染色体异常中的应用价值。方法回顾性分析2018年10月至2023年2月于怀化市妇幼保健院因不同产前诊断指征而行羊水穿刺术的3133例孕妇,比较羊水原位培养法和CMA法在胎儿染色体异常方面的检出率和差异。结果在3133例样本中,双指征组的异常检出率均较单指征组分别增加0.95%(羊水原位培养法)和2.36%(CMA);两种技术联合检测共检出796例异常(检出率25.41%),其中羊水原位培养法检出300例(9.58%),CMA法检出706例(22.53%)。两者均能检出145例非整倍体异常和31例染色体结构异常,但CMA另增加检出169例提示致病或可能致病的染色体拷贝数变异(CNV)、杂合性缺失(LOH)、杂合性不存在(AOH)/纯合区域(ROH)及单亲体二倍体异常(UPD),而羊水原位培养法增加检出11例染色体结构异常。两者联合检出嵌合体23例(0.73%)。结论羊水原位培养法与CMA技术互为补充,联合应用可显著提高胎儿染色体异常的检出率,可为产前遗传咨询提供更详细准确的信息,有助于孕妇决策是否终止妊娠。

关键词：染色体异常产前诊断羊水原位培养染色体微阵列分析染色体核型分析