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Science China Chemistry 2024年第2期67卷 732-740页

作者： Shuchi zhang Dengyun Miao Yi Ding Mengyuan Li Shujing Guo yujuan zhang Xiulian Pan Xinhe Bao State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China University of Chinese Academy of Sciences Beijing100049China Shaanxi Yanchang Petroleum(Group)Co. Ltd.&Dalian Institute of Chemical Physics Xi’an Clean Energy(Chemical Industry)Research InstituteXi’an710000China

Direct conversion of syngas to aromatics over metal oxide and zeolite(OXZEO) composite catalysts is ***,the selectivity of more valuable products such as benzene,toluene and xylenes(BTX) is limited due to undesired secondary methylation of ***,we report that the introduction of SAPO-34 into MnCrO_(x)-ZSM-5 catalyst enhances significantly the formation of BTX without sacrificing the aromatics *** optimized conditions,the fraction of BTX in aromatics reaches 64.7% versus 28.9% over the catalyst without SAPO-34.A number of model reaction tests and characterizations reveal that SAPO-34 consumes partially the intermediates such as ketene,by converting them to light ***,the methylation of BTX by ketene to heavy aromatics is inhibited over the external acid sites of ZSM-5,leading to an enhanced BTX selectivity in the *** hybrid catalyst provides an efficient method for highly selective synthesis of BTX from syngas.

关键词： selective syngas conversion OXZEO aromatics BTX multi-functional catalysts

Tribological properties and tribomechanism of nickel nanoparticles in-situ synthesized in rapeseed oil

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Friction 2024年第3期12卷 474-489页

作者： Wenya XU Guangbin YANG Shengmao zhang Jun XU yujuan zhang Tianhua SUN Ningning SONG Laigui YU Pingyu zhang Engineering Research Center for Nanomaterials Henan UniversityKaifeng 475004China State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China

Nickel(Ni)nanoparticles can be enriched on the surface of iron-based frictional pairs,which provides the possibility to get rid of the competitive adsorption between the polar species of vegetable oil and the surface-active nano-additives *** this paper,nickel acetylacetonate was used as a precursor to in-situ synthesize nickel nanoparticles with an average diameter of about 12 nm in rapeseed oil(RO)as the reducing agent,surface modifier,and solvent as *** tribological properties of the as-synthesized Ni nanoparticles were evaluated with a four-ball tribometer,and their tribomechanism was investigated based on the characterizations of the tribofilm on rubbed steel surfaces by the scanning electron microscopy(SEM),transmission electron microscopy(TEM),and X-ray photoelectron spectroscopy(XPS).It was found that the Ni nanoparticles in-situ prepared in the RO with a mass fraction of 0.3%can reduce the wear scar diameter(WSD)of the steel ball by 36%.This is because,on the one hand,the Ni nanoparticles are adsorbed on the rubbed steel surfaces to repair or fill up the micro-pits and grooves *** the other hand,Ni nanoparticles participate in tribochemical reactions with atmospheric O and steel substrate to form the tribochemical reaction film on the rubbed steel surfaces with the assistance of friction-induced heat and applied normal *** addition,an amorphous carbon film is formed on the rubbed surface via the carbonization of base oil under the catalysis of Ni *** adsorbed Ni layer,the tribochemical reaction film,and the carbon layer comprise a composite tribofilm composed of amorphous carbon,polar fatty acid,metallic nickel,iron oxides,and nickel oxides on the rubbed steel surfaces,which contributes to significantly improving the antiwear ability and load-carrying capacity of the RO for the steel-steel sliding pair.

关键词： nickel(Ni)nanoparticles rapeseed oil(RO) in-situ synthesis tribological properties tribomechanism

Genetic variants in C1GALT1 are associated with gastric cancer risk by influencing immune infiltration

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Journal of Biomedical Research 2024年第4期38卷 348-357页

作者： Mengfan Guo Jingyuan Liu yujuan zhang Jingjing Gu Junyi Xin Mulong Du Haiyan Chu Meilin Wang Hanting Liu Zhengdong zhang Departments of Environmental Genomics and Genetic Toxicology the Key Laboratory of Modern Toxicology of Ministry of EducationCenter for Global HealthJiangsu Key Laboratory of Cancer BiomarkersPrevention and TreatmentCollaborative Innovation Center for Cancer Personalized MedicineSchool of Public Health/Institute of Clinical Researchthe Affiliated Taizhou People's Hospital of Nanjing Medical UniversityNanjing Medical UniversityNanjingJiangsu 211166China Departments of Environmental Genomics and Genetic Toxicology the Key Laboratory of Modern Toxicology of Ministry of EducationCenter for Global HealthJiangsu Key Laboratory of Cancer BiomarkersPrevention and TreatmentCollaborative Innovation Center for Cancer Personalized MedicineSchool of Public HealthNanjing Medical UniversityNanjingJiangsu 211166China Department of Bioinformatics School of Biomedical Engineering and InformaticsNanjing Medical UniversityNanjingJiangsu 211166China Department of Biostatistics Center for Global HealthSchool of Public HealthNanjing Medical UniversityNanjingJiangsu 211166China

Core 1 synthase glycoprotein-N-acetylgalactosamine 3-β-galactosyltransferase 1(C1GALT1)is known to play a critical role in the development of gastric cancer,but few studies have elucidated associations between genetic variants in C1GALT1 and gastric cancer *** using the genome-wide association study data from the database of Genotype and Phenotype(dbGAP),we evaluated such associations with a multivariable logistic regression model and identified that the rs35999583 G>C in C1GALT1 was associated with gastric cancer risk(odds ratio,0.83;95% confidence interval[CI],0.75-0.92;P=3.95×10^(-4)).C1GALT1 mRNA expression levels were significantly higher in gastric tumor tissues than in normal tissues,and gastric cancer patients with higher C1GALT1 mRNA levels had worse overall survival rates(hazards ratio,1.33;95%CI,1.05-1.68;P_(log-rank)=1.90×10^(-2)).Furthermore,we found that C1GALT1 copy number differed in various immune cells and that C1GALT1 mRNA expression levels were positively correlated with the infiltrating levels of CD4^(+)T cells and *** results suggest that genetic variants of C1GALT1 may play an important role in gastric cancer risk and provide a new insight for C1GALT1 into a promising predictor of gastric cancer susceptibility and immune status.

关键词： O-glycosylation genetic variants immune status gastric cancer

Genetic variants in C1GALT1 are associated with gastric cancer risk by influencing immune infiltration

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The Journal of Biomedical Research 2024年第04期 348-357页

作者： Mengfan Guo Jingyuan Liu yujuan zhang Jingjing Gu Junyi Xin Mulong Du Haiyan Chu Meilin Wang Hanting Liu Zhengdong zhang Departments of Environmental Genomics and Genetic Toxicology the Key Laboratory of Modern Toxicology of Ministry of Education Center for Global Health Jiangsu Key Laboratory of Cancer Biomarkers Prevention and Treatment Collaborative Innovation Center for Cancer Personalized Medicine School of Public Health Institute of Clinical Research the Affiliated Taizhou People's Hospital of Nanjing Medical University Nanjing Medical University Departments of Environmental Genomics and Genetic Toxicology the Key Laboratory of Modern Toxicology of Ministry of Education Center for Global Health Jiangsu Key Laboratory of Cancer Biomarkers Prevention and Treatment Collaborative Innovation Center for Cancer Personalized Medicine School of Public Health Nanjing Medical University Department of Bioinformatics School of Biomedical Engineering and Informatics Nanjing Medical University Department of Biostatistics Center for Global Health School of Public Health Nanjing Medical University

Core 1 synthase glycoprotein-N-acetylgalactosamine 3-β-galactosyltransferase 1（C1GALT1） is known to play a critical role in the development of gastric cancer, but few studies have elucidated associations between genetic variants in C1GALT1 and gastric cancer risk. By using the genome-wide association study data from the database of Genotype and Phenotype（dbGAP）, we evaluated such associations with a multivariable logistic regression model and identified that the rs35999583 G>C in C1GALT1 was associated with gastric cancer risk(odds ratio,0.83; 95% confidence interval [CI], 0.75–0.92; P = 3.95 × 10-4). C1GALT1 mRNA expression levels were significantly higher in gastric tumor tissues than in normal tissues, and gastric cancer patients with higher C1GALT1mRNA levels had worse overall survival rates(hazards ratio, 1.33; 95% CI, 1.05–1.68; Plog-rank= 1.90 × 10-2).Furthermore, we found that C1GALT1 copy number differed in various immune cells and that C1GALT1 mRNA expression levels were positively correlated with the infiltrating levels of CD4+T cells and macrophages. These results suggest that genetic variants of C1GALT1 may play an important role in gastric cancer risk and provide a new insight for C1GALT1 into a promising predictor of gastric cancer susceptibility and immune status.

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火龙果果皮多糖对小鼠抗运动疲劳作用的研究

食品科技 2024年第4期49卷 220-228页

作者：张玉娟文武宜春职业技术学院江西宜春336000 宜春学院体育学院江西宜春336000

目的:火龙果果皮是火龙果的主要副产品,具有显著的生物活性。文章探讨不同剂量火龙果果皮多糖(Hylocereus undulatus *** polysaccharides,HPP)对小鼠的抗疲劳作用及其机制。方法:选取SPF级雄性昆明种小鼠100只,共设置5组:空白对照组、... 详细信息

目的:火龙果果皮是火龙果的主要副产品,具有显著的生物活性。文章探讨不同剂量火龙果果皮多糖(Hylocereus undulatus *** polysaccharides,HPP)对小鼠的抗疲劳作用及其机制。方法:选取SPF级雄性昆明种小鼠100只,共设置5组:空白对照组、模型组及低、中、高剂量组HPP(100、200、400 mg/kg)。结果:抗氧化活性试验表明,HPP具有一定的抗氧化能力。动物试验表明,HPP不同剂量组可显著延长小鼠疲劳转棒和负重力竭游泳时间,使运动后小鼠肝糖原和肌糖原的储备量明显增加,提高乳酸脱氢酶(Lactate dehydrogenase,LDH)活性,并有效抑制代谢产物血乳酸(Blood lactic acid,BLA)和血尿素氮(Blood urea nitrogen,BUN)含量的堆积(P<0.05),且可提高超氧化物歧化酶(Superoxide dismutase,SOD)、过氧化氢酶(Catalase,CAT)和谷胱甘肽过氧化物酶(Glutathione peroxidase,GSH-Px)活性(P<0.05),降低活性氧自由基(Reactive oxygen species,ROS)、肌酸激酶(Creatine kinase,CK)和丙二醛(Malondialdehyde,MDA)含量。结论:添加HPP有利于缓解机体运动性疲劳,为HPP在医药和功能食品中的开发和应用提供了基础依据。

关键词：火龙果果皮多糖抗疲劳抗氧化活性运动

低硫柴油用纳米氧化铈抗磨助燃添加剂的性能研究

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内燃机工程 2024年第3期45卷 95-101页

作者：陈智超张晟卯张玉娟余来贵河南大学纳米材料工程研究中心开封475004

为了解决深度脱硫工艺导致的柴油摩擦学性能差引起的喷油器磨损失效问题及纳米添加剂粒径大分散性差等问题,制备了超小粒径(1~2 nm)CeO_(2)纳米微粒,其拥有优异的分散性。将其作为0号柴油添加剂,采用四球摩擦磨损试验机和自动量热仪测... 详细信息

为了解决深度脱硫工艺导致的柴油摩擦学性能差引起的喷油器磨损失效问题及纳米添加剂粒径大分散性差等问题,制备了超小粒径(1~2 nm)CeO_(2)纳米微粒,其拥有优异的分散性。将其作为0号柴油添加剂,采用四球摩擦磨损试验机和自动量热仪测试了其摩擦学性能和助燃性能,采用热重分析仪在氧气气氛下分析柴油的氧化燃烧过程。结果表明,向柴油中添加CeO_(2)纳米微粒能够增强其减摩抗磨性能,与柴油相比磨斑直径减小约13%,摩擦系数降低约27%,燃烧热值提高约16%。

关键词：柴油超小氧化铈添加剂性能

纳米材料在漆酶电化学传感器中的应用和研究进展

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分析试验室 2024年第5期43卷 737-748页

作者：张钰涓陶文强张志衡宋志华钱立生张越安徽科技学院生命与健康科学学院滁州233100 安徽科技学院食品工程学院滁州233100

高性能纳米材料通过负载漆酶制备生物传感电极,可以实现漆酶电化学传感器的高灵敏度、宽线性检测范围、较好的稳定性和较强的固定化强度,能够应用于食品、环境、医药等领域目标物浓度的精准检测。近年来,随着许多新型纳米材料不断开发... 详细信息

高性能纳米材料通过负载漆酶制备生物传感电极,可以实现漆酶电化学传感器的高灵敏度、宽线性检测范围、较好的稳定性和较强的固定化强度,能够应用于食品、环境、医药等领域目标物浓度的精准检测。近年来,随着许多新型纳米材料不断开发以及与漆酶分子之间固定化方式研究的不断深入,证明了纳米材料在漆酶电化学传感电极构建中的巨大潜力。开发新型纳米材料和建立与酶分子之间搭配和固定化策略,能够实现高性能传感电极的制备,进而指导组建面向性能需求的高应用性传感器,最终推动生物传感、酶工程与蛋白质工程和材料学之间的交叉应用。本文对固定漆酶制备传感电极的高性能纳米材料种类进行了分析与讨论,主要从金属纳米材料、碳纳米材料和高分子纳米材料固定化漆酶在生物电化学传感方面的研究进展进行综述,并对纳米材料在漆酶电化学中的应用前景与未来进行了讨论,为今后在漆酶电化学传感器中开发新型纳米材料和选择固定化方式提供参考。

关键词：漆酶纳米材料电化学

Nonlinear Analysis of Axial-load and Stress Distribution for Threaded Connection

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Chinese Journal of Mechanical Engineering 2009年第6期22卷 869-875页

作者： LIAO Ridong SUN yujuan zhang Weizheng School of Mechanical Engineering Beijing Institute of Technology Beijing 100081 China

Analytical method for the distributions of axial-load and stress is based on elastic assumption, but the threaded connections are often in plastic deformation stage in practice. Meanwhile the strain in the threaded connection is difficult to measure. So it is necessary to study the reliable numerical method. At present neither the convergence analysis of the computational results nor the elastic-plastic analysis in the loading-unloading process are studied. In this paper, von Mises plasticity and kinematic hardening model is used to describe the material response. A new convergence criterion for nonlinear finite element analysis of the loading-unloading process is proposed. An axisymmetric finite element model according to the proposed convergence criterion is developed and used to analyze the distributions of axial-load and stress. It can be conclude that the stress distribution analysis is more dependent on the mesh density than the axial-load distribution analysis. The stress distribution result indicates that with increasing of applied load, the engaged threads close to the nut-bearing surface become plastic firstly. The axial-load distribution result reveals that the load percentage carried by single thread depends on the position of thread and load intensity. When the load is relatively small, the applied load is mainly carried by the engaged threads near the nut-bearing surface, when the load is larger, the differences of percentages for all threads become small. The proposed convergence analyzing procedure is applicable for other nonlinear analyses. The obtained distributions of axial-load and stress can be a reference of engineering application.

关键词： threaded connection finite element method (FEM) axial-load distribution stress distribution convergence criterion

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草地早熟禾苗期耐低温的生理特性研究

中国草地学报 2024年第5期46卷 33-43页

作者：董文科张玉娟马福钦陈佐惠周晓爽张蓓张佳能甘肃农业大学草业学院/草业生态系统教育部重点实验室/甘肃省草业工程实验室/中-美草地畜牧业可持续发展研究中心/农业农村部饲草种质创新与新品种选育重点实验室甘肃兰州730070

为了探究不同抗性草地早熟禾苗期对低温胁迫的生理特性差异,以10个常用草地早熟禾品种为试验材料,将幼苗叶片进行不同程度的低温胁迫处理,利用细胞伤害率和对应的低温度梯度进行Logistic方程拟合,获得半致死温度(LT50)并筛选抗寒品种和... 详细信息

为了探究不同抗性草地早熟禾苗期对低温胁迫的生理特性差异,以10个常用草地早熟禾品种为试验材料,将幼苗叶片进行不同程度的低温胁迫处理,利用细胞伤害率和对应的低温度梯度进行Logistic方程拟合,获得半致死温度(LT50)并筛选抗寒品种和低温敏感品种,并以二者为试验材料进行相关生理指标的测定和相关性分析。结果表明,草地早熟禾‘普瑞芬’的LT_(50)为-17.5℃,表现出较好的抗寒性,‘帝国’的LT_(50)为-3.2℃,表现出对低温的敏感性;经低温胁迫处理后抗寒品种‘普瑞芬’的相对电导率和丙二醛含量显著下降并低于低温敏感品种‘帝国’,而‘普瑞芬’幼苗中干物质含量、相对含水量和苗长等生长指标和叶绿素含量、渗透调节物质(游离脯氨酸、可溶性糖和可溶性蛋白)和抗氧化酶活性(SOD、POD和CAT)均高于‘帝国’;经相关性分析表明,低温对草地早熟禾幼苗的干物质,苗长和根长及渗透调节物质含量影响较大且各指标之间相互作用。

关键词：草地早熟禾低温胁迫半致死温度生理特性相关性

Preparation and catalytic performance of Fe-SBA-15 and FeO_x/SBA-15 for toluene combustion

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Chinese Science Bulletin 2014年第26期59卷 3993-4002页

作者： yujuan zhang Jiguang Deng Lei zhang Hongxing Dai Laboratory of Catalysis Chemistry and Nanoscience Department of Chemistry and Chemical EngineeringCollege of Environmental and Energy EngineeringBeijing University of Technology

High-surface-area and well-ordered mesoporous Fe-incorporated SBA-15(xFe-SBA-15)and SBA-15-supported FeOx(yFeOx/SBA-15)with the Fe surface density between 0.09 to 1.11 Fe-atom/nm2have been prepared using the one-step synthesis and incipient wetness impregnation methods,*** properties of these materials were characterized by means of numerous techniques,and their catalytic activities for the combustion of toluene were *** is found that the xFe-SBA-15 and yFeOx/SBA-15 samples possessed rod-or chain-like *** Fe species were of high dispersion when the Fe surface density was lower than0.76 Fe-atom/nm2in xFe-SBA-15 and 0.64 Fe-atom/nm2in yFeOx/*** a similar Fe surface density and space velocity,the xFe-SBA-15 catalysts showed better activity than the yFeOx/SBA-15 catalysts,in which the xFe-SBA-15 catalyst with Fe surface density 0.59 Fe-atom/nm2performed the *** is concluded that the good performance of the xFe-SBA-15 sample with Fe surface density0.59 Fe-atom/nm2was associated with its large surface area,high Fe species dispersion,and good low-temperature reducibility.

关键词： SBA-15 催化性能燃烧甲苯编制表面密度物理化学性质高表面积