检索结果-南通市图书馆

Micro Mechanical Model of 3D Woven Composites

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2005年第1期18卷 40-46页

作者：周储伟 College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

A combined beam model representing the periodicity of the microstructure and micro deformation of 3D woven composites is developed for predicting mechanical properties. The model considers the effects of off axial tension/compression and bending/shearing couplings as well as the mutual reactions of fiber yarns. The method determining microstructure by using woven parameters is described for a typical 3D woven composite material. An analytical cell, constructed by a minimum periodic section of yarn and interlayer matrix, is adopted. Micro stresses in the cell under in-plane tensile loading are obtained by using the proposed beam model and macro modulus is then obtained by the averaging method. Material tests and a 2D micro FEM analysis are made to evaluate this model. Analyses reveal that micro stress caused by tensile/bending coupling effect is not negligible in the stress analysis.

关键词： 3D woven composites micro mechanics bending/shear coupling off axial effect combined beam model

Anti-EGFR therapy in metastatic colorectal cancer:mechanisms and potential regimens of drug resistance

在线全文

学校读者我要写书评

暂无评论

Gastroenterology Report 2020年第3期8卷 179-191,I0001页

作者： Qing-Hai Li Ying-Zhao Wang Jian Tu chu-wei Liu Yu-Jie Yuan Run Lin wei-Ling He Shi-Rong Cai Yu-Long He Jin-Ning Ye Department of Gastrointestinal Surgery the First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongP.R.China Department of Musculoskeletal Oncology the First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongP.R.China Department of Radiology the First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongP.R.China

Cetuximab and panitumumab,as the highly effective antibodies targeting epidermal growth factor receptor(EGFR),have clinical activity in the patients with metastatic colorectal cancer(mCRC).These agents have good curative efficacy,but drug resistance also exists at the same *** effects of KRAS,NRAS,and BRAF mutations and HER2 amplification on the treatment of refractory mCRC have been elucidated and the corresponding countermeasures have been put ***,the changes in EGFR and its ligands,the mutations or amplifications of PIK3CA,PTEN,TP53,MET,HER3,IRS2,FGFR1,and MAP2K1,the overexpression of insulin growth factor-1,the low expression of Bcl-2-interacting mediator of cell death,mismatch repair-deficient,and epigenetic instability may also lead to drug resistance in *** the emergence of drug resistance has genetic or epigenetic heterogeneity,most of these molecular changes relating to it are focused on the key signaling pathways,such as the RAS/RAF/mitogen-activated protein kinase or phosphatidylinositol 3-kinase/Akt/mammalian target of the rapamycin ***,numerous efforts to target these signaling pathways and develop the novel therapeutic regimens have been carried ***,we have reviewed the underlying mechanisms of the resistance to anti-EGFR therapy and the possible implications in clinical practice.

关键词： metastatic colorectal cancer EGFR drug resistance cetuximab panitumumab

Catalytic performances of Ni/mesoporous SiO_2 catalysts for dry reforming of methane to hydrogen

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2016年第4期25卷 709-719页

作者： Fei Huang Rui Wang Chao Yang Hafedh Driss wei chu Hui Zhang College of Chemistry and Chemical Engineering Southwest Petroleum University Oil & Gas Field Applied Chemistry Key Laboratory of Sichuan Province Drilling & Production Engineering Technology Research Institute CNPC Chuanqing Drilling Engineering Co.Ltd. SABIC Chair in Catalysis King Abudulaziz University Department of Chemical Engineering Sichuan University

Several mesoporous silicas with different morphologies were controllably prepared by sol-gel method with adjustable ratio of dual template, and they were further impregnated with aqueous solution of nickel nitrate, followed by calcination in air. The synthesized silica supports and supported nickel samples were characterized using N2-adsorption/desorption, X-ray diffraction (XRD), H2temperature-programmed reduction (H2-TPR), Scanning electron microscope (SEM), Transmission electron microscope (TEM) and thermo-gravimetric analysis (TGA-DTG) techniques. The Ni nanoparticles supported on shell-like silica are highly dispersed and yielded much narrower nickel particle-size than those on other mesoporous silica. The methane reforming with dioxide carbon reaction results showed that Ni nanoparticles supported on shell-like silica carrier exhibited the better catalytic performance and catalytic stability than those of nickel catalyst supported on other silica carrier. The thermo-gravimetric analysis on used nickel catalysts uncovered that catalyst deactivation depends on the type and nature of the coke deposited. The heterogeneous nature of the deposited coke was observed on nickel nanoparticles supported on spherical and peanut-like silica. Much narrower and lower TGA derivative peak was founded on Ni catalyst supported on the shell-like silica. © 2016 Science Press

关键词： Carbon Catalyst activity Catalyst deactivation Catalysts Catalytic reforming Coke Gravimetric analysis Hydrogen Methane Nanoparticles Nickel Particle size Scanning electron microscopy Silica Sol gel process Sol gels Solutions Thermogravimetric analysis Transmission electron microscopy X ray diffraction

Doping effects of manganese on the catalytic performance and structure of NiMgO catalysts for controllabe synthesis of multi-walled carbon nanotubes

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2014年第6期23卷 781-788页

作者： Maofei Ran wei chu Yan Liu Dong Liu Chang Zhang Jiae Zheng College of Chemistry & Environment Protection Engineering Southwest University for Nationalities Institute of Chemical and Engineering Sciences (ICES) A*STAR 627833 Singapore College of Chemical Engineering Sichuan University

Doping effects of manganese （Mn） on catalytic performance and structure evolution of NiMgO catalysts for synthesis of multi-walled carbon nanotubes （MWCNTs） from methane were investigated for the first time. Addition of Mn in NiMgO catalyst can greatly improve the MWCNTs yield. Mno.2NiMgO catalyst among the tested ones gives the highest MWCNTs yield as 2244%, which is two times higher than that of the catalyst without Mn. The structure evolution, reduction behaviors and surface chemical properties of MnNiMgO catalysts with various Mn contents were studied in detail. It was found that the stable solid solution of NiMgO2 formed in NiMgO catalyst was disturbed by the addition of Mn. Instead, another solid solution of MnMg608 is formed. More amount of Ni can be reduced and dispersed on the catalyst surface to be acted as active sites. Importantly, the changes of Ni content on the surface are correlated with the Ni particle size and the outer diameter of MWCNTs, suggesting the controllable synthesis of MWCNTs over MnNiMgO catalysts.

关键词： doping effect manganese NiMgO catalyst controllable synthesis carbon nanotubes

Improvement of catalytic stability for CO_2 reforming of methane by copper promoted Ni-based catalyst derived from layered-double hydroxides

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2016年第6期25卷 1078-1085页

作者： Bing Li Zhenxin Xu Fangli Jing Shizhong Luo Ning Wang wei chu Department of Chemical Engineering Sichuan University Institut de Chimie et Procedes pour l’Energie l’Environnement et la Sante (ICPEES) UMR 7515 CNRS Universite de Strasbourg (UdS) Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical Engineering Tsinghua University

Copper-promoted nickel-based metal nanoparticles (NPs) with high dispersion and good thermal stability were derived from layered-double hydroxides (LDHs) precursors that were facilely developed by a co-precipitation strategy. The copper-promoted Ni-based metal NPs catalysts were investigated for methane reforming with carbon dioxide to hydrogen and syngas. A series of characterization techniques including XRD, N2adsorption and desorption, H2-TPR, XPS, CO2-TPD, TEM, TGA and in situ CH4-TPSR were utilized to determine the structure-function relationship for the obtained catalysts. The copper addition accelerated the catalyst reducibility as well as the methane activation, and made the Ni species form smaller NPs during both preparation and reaction by restricting the aggregation. However, with higher copper loading, the derived catalysts were less active during methane reforming with CO2to syngas. It was confirmed that the catalyst with 1 wt% Cu additive gave the higher catalytic activity and remained stable during long time reaction with excellent resistance to coking and to sintering. Furthermore, the mean size of metal NPs changed minimally from 6.6 to 7.9 nm even after 80 h of time on stream at temperature as high as 700 °C for this optimized catalyst. Therefore, this high dispersed anti-coking copper-promoted nickel catalyst derived from LDHs precursor could be prospective catalyst candidate for the efficient heterogeneous catalysis of sustainable CO2conversion. © 2016 Science Press

关键词： Carbon dioxide Catalysis Catalysts Copper Metal nanoparticles Methane Nickel Precipitation (chemical) Sintering Synthesis gas

Theoretical insight into the enhanced CH_4 desorption via H_2O adsorption on different rank coal surfaces

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2016年第4期25卷 677-682页

作者： Yanan Zhou Wenjing Sun wei chu Xiaoqiang Liu Fangli Jing Ying Xue College of Chemical Engineering Sichuan University Key Laboratory Green Chemistry & Technology of Ministry of Education (MOE) College of Chemistry Sichuan University Dongguan Scientific Research Center Guangdong Medical College

The density functional theory was used to investigate the adsorption of CH4and H2O on different rank coal surfaces. The coal rank is the dominant factor in affecting the adsorption capacity of coal. In order to better understand gas and water interaction with coal of different maturity, we developed fourteen coal models to represent the different rank coal. The interactions of CH4and H2O with coal surfaces were studied and characterized by their adsorption energies, Mulliken charges and electrostatic potential surfaces. The results revealed that the interaction between coal and CH4was weak physical adsorption, and that the interaction between coal and H2O consisted of physical and chemical adsorption. Adsorption energy of coal–H2O system was larger than that of coal–CH4on all rank coals, suggesting that the adsorption priority in the coal models is H2O > CH4. Consequently, the injection of H2O into the different rank coal could effectively enhance the coal bed methane (CBM) recovery. © 2016 Science Press

关键词： Adsorption Coal Coal bed methane Coal deposits Density functional theory Methane

在线全文

学校读者我要写书评

暂无评论

基于球面重力反演苏拉威西地区莫霍面结构

地球物理学报 2022年第6期65卷 2198-2209页

作者：褚伟徐亚郝天珧中国科学院大学地球与行星科学学院北京100049 中国科学院地质与地球物理研究所中国科学院油气资源研究重点实验室北京100029 中国科学院地球科学研究院北京100029 海底科学重点实验室自然资源部第二海洋研究所杭州310012

基于球坐标系的地球物理反演能有效避免地球曲率的影响,适用于大尺度构造研究.本文基于重力异常数据在球坐标系下反演莫霍面深度,结合数据误差及光滑正则化项建立反演目标函数并求解,同时将该方法应用于苏拉威西地区.苏拉威西地区具有... 详细信息

基于球坐标系的地球物理反演能有效避免地球曲率的影响,适用于大尺度构造研究.本文基于重力异常数据在球坐标系下反演莫霍面深度,结合数据误差及光滑正则化项建立反演目标函数并求解,同时将该方法应用于苏拉威西地区.苏拉威西地区具有复杂的断裂系统、年轻的俯冲带,是研究俯冲起始机制等前沿科学问题的理想场所.目前研究区的地球物理观测尚不充分,缺乏对莫霍面形成有效约束的地震数据,对研究区莫霍面的整体认识较少.本文基于卫星重力观测数据,通过匹配滤波方法提取与研究区莫霍面结构相关的重力异常,并结合频谱分析确定该地区的莫霍面深度参考值.在反演中,通过两次随机子抽样交叉验证选择最优的超参数,包括正则化因子、莫霍面密度差以及参考莫霍面深度,迭代反演获得莫霍面深度.反演结果表明:研究区莫霍面平均深度为20.0 km,深度变化范围为9.2~33.3 km.总体上,海区莫霍面浅,约10.0~20.0 km,陆区莫霍面深,约25.0~33.0 km,该结果与Crust1.0全球模型、前人重力反演结果以及地震数据基本相符,总体上反映了苏拉威西地区的莫霍面变化特征.

关键词：苏拉威西球坐标系重力反演莫霍面匹配滤波

维普期刊数据库博看期刊

Automated and remote synthesis of poly(ethylene glycol)-mineralized ZIF-8 composite particles via a synthesizer assisted by femtosecond laser micromachining

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2022年第1期33卷 497-500页

作者： Miao Wu Lingling Xia Yucen Li Difeng Yin Jianping Yu Wenbo Li Ning Wang Xin Li Jiwei Cui wei chu Ya Cheng Ming Hu School of Physics and Electronic Science East China Normal UniversityShanghai 200241China State Key Laboratory of Precision Spectroscopy School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241 China XXL–The Extreme Optoelectromechanics Laboratory School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241 China State Key Laboratory of High Field Laser Physics and CAS Center for Excellence in Ultra-intense Laser Science Shanghai Institute of Optics and Fine Mechanics(SIOM)Chinese Academy of Sciences(CAS)Shanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Colloid and Interface Chemistry of the Ministry of Education School of Chemistry and Chemical EngineeringShandong UniversityJi'nan 250100China

Mineralization of the ZIF-8 in the presence of biomacromolecules has been demonstrated to be a general way for making bioentities@ZIFs *** ZIF-8 crystals permit controlled storage and utilization of the bioentities,thus can benefit drug delivery,cold-chain breaking *** the increasing needs on personal care and distributed manufacturing,automated synthesis controlled by a computer becomes the next *** this work,we designed an automatic synthesis system to prepare PEG mineralized ZIF-8 composite *** system is based on flow chemistry with the microfluidic chips fabricated by femtosecond laser *** particles were synthesized and monitored ***,this synthesizer could be extended for fabrication of vaccine particles under remote control through internet.

关键词： ZIF-8 Automatic synthesis Remote synthesis MOFs Vaccine particles Microfluidic chip Flow chemistry

城镇化会增加居民能源需求吗——基于事实与文献的述评

在线全文

学校读者我要写书评

暂无评论

经济理论与经济管理 2017年第1期37卷 95-109页

作者：魏楚中国人民大学经济学院

城市消耗了中国70%的能源总量,新型城镇化发展要求实现"高城镇化、低能源消耗"。未来的城镇化是否会推高居民能源需求?以往观点往往得出肯定的结论。本文基于典型事实和逻辑推理对此提出质疑,分别对基于"自上而下"和"自下而上"视角的两... 详细信息

城市消耗了中国70%的能源总量,新型城镇化发展要求实现"高城镇化、低能源消耗"。未来的城镇化是否会推高居民能源需求?以往观点往往得出肯定的结论。本文基于典型事实和逻辑推理对此提出质疑,分别对基于"自上而下"和"自下而上"视角的两类文献进行了综述和比较,并构建了一个融合两种研究视角的传导机制分析框架。在系统总结现有文献的基础上,本文提出未来三个可创新的方向:首先是融合不同学科与视角,将微观居民的用能行为置于城镇化这一动态变迁中进行研究;其次是突破数据和研究方法局限,运用微观数据和实验性方法来科学识别相关性和因果性,并进行政策影响评估;最后是结合国际化视野和规范分析方法来研究中国城镇化中的能源、环境等本土问题,并凝练形成城镇低碳化发展的"中国模式"与"中国经验"。

关键词：城镇化居民能源需求影响机制文献综述