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硅颗粒增强铝基复合材料的制备与激光焊接行为

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稀有金属 2019年第12期43卷 1251-1259页

作者：刘彦强马自力魏少华樊建中郝心想左涛有研工程技术研究院有限公司国家有色金属复合材料工程技术研究中心

硅颗粒增强铝基复合材料(Si/Al)具有低热膨胀、高导热、可焊接的综合性能,能够很好满足微电子器件封装的技术要求,在微电子封装领域具有广阔的应用前景。激光焊接工艺性能是微电子封装的重要应用工艺之一,也是制约封装材料应用的瓶颈问... 详细信息

硅颗粒增强铝基复合材料(Si/Al)具有低热膨胀、高导热、可焊接的综合性能,能够很好满足微电子器件封装的技术要求,在微电子封装领域具有广阔的应用前景。激光焊接工艺性能是微电子封装的重要应用工艺之一,也是制约封装材料应用的瓶颈问题之一。为了提高Si/Al复合材料的激光焊接工艺性能,本文采用工艺灵活的粉末冶金技术,根据粉末的粒度和纯度的差异设计制备了4种组分的50%Si/Al和两种27%Si/Al复合材料,在较宽的激光参数范围内研究了材料的激光焊接行为。结果表明,粉末粒度和纯度的调整极大地影响了材料对激光的响应特点,对焊缝表面成型、焊接气孔率以及熔池尺寸都产生了较大影响。其中,粉末粒度较粗、纯度较低的50%Si/Al复合材料的焊接气孔率最低,预计具有较高的气密性。本文的研究结果对于提高Si/Al复合材料的激光焊接气密性、推动粉末冶金铝基复合材料在电子领域的应用具有重要意义。

关键词：硅/铝(Si/Al)复合材料粉末冶金激光焊接焊接气孔

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碰撞造山带斑岩型矿床的深部约束机制

岩石学报 2008年第3期24卷 447-456页

作者：罗照华卢欣祥陈必河黄凡杨宗锋王秉璋中国地质大学地质过程与矿产资源国家重点实验室北京100083

在印度-亚洲大陆碰撞过程中,俯冲板片断离触发了幔源岩浆底侵作用、下地壳部分熔融和冈底斯岩基带以及同岩基斑岩的产生。在此过程中,幔源岩浆分离结晶的产物、下地壳岩石部分熔融残余和地壳分异过程中下沉的镁铁质块体,构成了加厚下地... 详细信息

在印度-亚洲大陆碰撞过程中,俯冲板片断离触发了幔源岩浆底侵作用、下地壳部分熔融和冈底斯岩基带以及同岩基斑岩的产生。在此过程中,幔源岩浆分离结晶的产物、下地壳岩石部分熔融残余和地壳分异过程中下沉的镁铁质块体,构成了加厚下地壳。随着造山岩石圈的冷却和加厚下地壳重力不稳定性的增加,岩石圈拆沉作用触发了后碰撞斑岩型岩浆活动。与此相应,碰撞造山带斑岩型矿床可以形成于同碰撞和后碰撞两个不同的构造阶段。同碰撞成矿作用发生于岩基带形成时期,成矿物质主要来自于底侵幔源岩浆及更深部的含矿流体,其触发机制是俯冲板片的断离。后碰撞成矿作用发生于加厚下地壳冷却之后,成矿物质主要来自于新生矿源层和更深部的含矿流体,其触发机制为岩石圈拆沉作用。在同碰撞构造阶段,伴随着幔源岩浆的底侵作用,深部流体和幔源岩浆所含的成矿物质被注入到岩基岩浆中,与从岩基岩浆源区萃取的成矿物质汇聚在一起,一部分受岩基热的驱使上升成矿。由于流体中成矿元素的浓度强烈依赖于压力,另一部分成矿元素则滞留在难熔残余中形成新的矿源层。当发生岩石圈拆沉作用时,由此矿源层部分熔融形成的斑岩岩浆将相对富含成矿物质,导致碰撞造山带第二次成矿作用大爆发。

关键词：碰撞造山带斑岩型矿床深部过程岩石圈拆沉作用矿源层

Disordered Fragments of Chemical Structures Based on Single-crystal X-ray Diffraction

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Chinese Journal of Structural Chemistry 2020年第4期39卷 698-708页

作者： ZHANG Jun MA Xiao-fan XUAN Xiao-Peng School of Materials and Chemical Engineering Anhui Jianzhu UniversityHefei 230601China Key Laboratory of Green Chemical Media and Reactions Ministry of EducationCollaborative Innovation Center of Henan Province for Green Manufacturing of Fine ChemicalsSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenan 453007China Department of Chemistry The Hong Kong University of Science&TechnologyHong KongChina

For the reported chemical structures,the disordered fragments of the structure acting as hosts and guests are common and unmanageable for *** to analyze and treat such disordered assemblies is an important task for *** is often difficult for some researchers to refine the disordered structures,even to mechanically justify the refined consequence in the absence of ***,some examples of disorder refinements selected from the literature,including the disordered assemblies of nitrate,perchlorate,alkyl,aromatic assemblies,and guest solvent molecules,are summarized and discussed to provide practical advice for investigating the disorders for crystallographic researchers and *** refinement approach for these disordered assemblies is also discussed in detail,which is helpful for crystallographers.

关键词： single-crystal X-ray diffraction crystal-structure refinement disorder disordered assemblies

前驱体合金化方式对粉末冶金泡沫铝孔结构的影响

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稀有金属 2017年第9期41卷 1003-1011页

作者：孙琦刘彦强樊建中魏少华马自力郝心想北京有色金属研究总院国家有色金属复合材料工程技术研究中心北京100088

以Al Si11合金为对象,选取了预合金化的粉末和元素混合粉末作为前驱体的原料,以Ti H2粉末为发泡剂,采用粉末冷等静压、真空热除气、热挤压成形等工艺制备前驱体、再次加热发泡成型的方法制备了不同时间状态的一系列泡沫铝试样;对系列试... 详细信息

以Al Si11合金为对象,选取了预合金化的粉末和元素混合粉末作为前驱体的原料,以Ti H2粉末为发泡剂,采用粉末冷等静压、真空热除气、热挤压成形等工艺制备前驱体、再次加热发泡成型的方法制备了不同时间状态的一系列泡沫铝试样;对系列试样的孔隙率、孔径及其分布、孔形貌等参数的演变规律进行了对比研究;对孔壁微观组织进行了金相表征。结果表明,预合金粉前驱体制备的泡沫铝试样的最大孔隙率为72%,平均孔径为0.59~3.38 mm,孔径分布不均匀;气孔演化过程经历了气孔形核、气孔长大和快速合并阶段,发泡后期出现严重排液现象。元素混合粉前驱体制备的泡沫铝试样的最大孔隙率为84%,平均孔径为0.58~1.99 mm,孔径分布较为均匀;气孔经历了形核、快速合并长大和气孔缓速合并3个阶段。二者相比,元素混合粉前驱体的可发泡性更好、气孔稳定性更好;结合组织分析可知,前驱体中AlSi组织特征(尤其是界面形态)的差异从本质上决定了合金的熔化和凝固行为,进而对气孔形核和演化产生了较大的影响。

关键词：粉末冶金泡沫铝孔结构

Research progresses on cathode materials of aqueous zinc-ion batteries

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Journal of Energy Chemistry 2024年第10期97卷 237-264,I0005页

作者： Zengyuan fan Jiawei Wang Yunpeng Wu Xuedong Yan Dongmei Dai Xing-Long Wu Jilin Provincial Science and Technology Innovation Centre of Optical Materials and Chemistry Jilin Provincial International Joint Research Center of Photo-functional Materials and ChemistrySchool of Chemistry and Environmental EngineeringChangchun University of Science and TechnologyChangchun 130022JilinChina PMOE Key Laboratory for UV LightEmitting Materials and Technology School of PhysicsNortheast Normal UniversityChangchun 130024JilinChina Chongqing Research Institute Changchun University of Science and TechnologyChongqing 401135China Institute of Energy Storage and Conversion Technology College of Chemical EngineeringNingbo PolytechnicNingbo 315800ZhejiangChina School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007HenanChina

Electrochemical energy storage and conversion techniques that exhibit the merits such as high energy density,rapid response kinetics,economical maintenance requirements and expedient installation procedures will hold a pivotal role in the forthcoming energy storage technologies *** recent years,aqueous zinc-ion batteries(AZIBs)have garnered substantial attention as a compelling candidate for large-scale energy storage systems,primarily attributable to their advantageous featu res encompassing cost-effectiveness,environmental sustainability,and robust safety ***,one of the primary factors hindering the further development of AZIBs originates from the challenge of cathode ***,the three mainstream types of mainstream cathode materials,in terms of manganese-based compounds,vanadium-based compounds and Prussian blue analogues,surfer from the dissolution of Mn~(2+),in the low discharge voltage,and the low specific capacity,*** strategies have been developed to compensation the above intrinsic defects for these cathode materials,including the ionic doping,defect engineering,and materials ***,this review first provides a systematic summarization of the zinc storage mechanism in AZIBs,following by the inherent merit and demerit of three kind of cathode materials during zinc storage analyzed from their structure characteristic,and then the recent development of critical strategies towards the intrinsic insufficiency of these cathode *** this review,the methodologies aimed at enhancing the efficacy of manganese-based and vanadium-based compounds are emphasis ***,the article outlines the future prospective directions as well as strategic proposal for cathode materials in AZIBs.

关键词： Aqueous zinc-ion batteries Cathode materials Optimization strategies

Synthesis and electrochemical properties of Th-doped LiMn_2O_4 powders for lithium-ion batteries

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Rare Metals 2006年第Z1期25卷 58-61页

作者： LI Chao fan Yanliang LI Shuzhong XIE Bing BI Lei YANG Shuting Department of Applied Chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Engineering Research Centre for New Power Source Materials of Henan Province Xinxiang 453002 China Department of Applied Chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Engineering Research Centre for New Power Source Materials of Henan ProvinceXinxiang 453002 China Department of Applied Chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Department of Applied Chemistry College of Material Science and Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou 450002 China Department of Chemical Engineering College of Chemistry and Environmental Science Henan Normal University Xinxiang 453002 China

To improve the cycle performance of eco-friendly and cost-effective spinel LiMn2O4 as the Li secondary batteries, the Th-doped LiThxMn1-xO4 spinel powers were synthesized by solid-state method. The starting materials, Li2CO3, MnO2 and Th(NO3)4·4H2O, were mixed uniformly using a traditional ball milling, which resulted in a uniform particle size distribution in the mixed powers. Tests of X-ray diffraction, SEM, impedance spectra and charge-discharge were carried out for LiThxMn1-xO4 cathode materials. Results show that the synthesized LiTh0.01Mn1.99O4 material exhibits standard spinel structure, regular particle morphology and excellent property of charge-discharge for big current. The capacity retention of the material modified by doping Th is more than 85.1% of the first discharge specific capacity of 111.5 mAh·g-1 after 20 cycles at the current rate 1C, while the pristine LiMn2O4 is only 57% of the first discharge specific capacity of 110.2 mAh·g-1 after the same cycles at the same current rate.

关键词： lithium ion batteries Th-doped electrochemical properties AC impedance

Current health resources required for the management of ankylosing spondylitis in developing areas of China

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Chinese Medical Journal 2023年第6期136卷 737-739页

作者： Yi Zhao Qian Wang Lihua Duan xinxiang Huang Pei Wang Ping fan Qinghua Zou Zhiming Lin Jiuliang Zhao Xin Wu Li Wang Yan Gen Xiaoxia Zhu Zhuoli Zhang Wen Zhang Yan Zhao Department of Rheumatology and Immunology West China HospitalSichuan UniversityChengduSichuan 610041China Clinical Institute of Inflammation and Immunology(CIII) Frontiers Science Center for Disease-related Molecular NetworkWest China HospitalSichuan UniversityChengduSichuan 610041China Department of Rheumatology Peking Union Medical College HospitalPeking Union Medical College&Chinese Academy of Medical SciencesNational Clinical Research Center for Dermatologic and Immunologic Diseases(NCRC-DID)Key Laboratory of Rheumatology and Clinical ImmunologyMinistry of EducationBeijing 100730China Department of Rheumatology and Clinical Immunology Jiangxi Provincial People’s HospitalNanchangJiangxi 330006China Department of Rheumatology The People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous Region 530021China Department of Rheumatology and Immunology Henan Provincial People’s HospitalPeople’s Hospital of Zhengzhou UniversityZhengzhouHenan 450003China Department of Rheumatism and Immunology The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’anShaanxi 710061China Department of Rheumatology and Immunology The First Hospital Affiliated to Army Medical UniversityChongqing 400038China Department of Rheumatology The Third Affiliated Hospital of Sun Yat-Sen UniversityGuangzhou 510630China Department of Rheumatology and Immunology Shanghai Changzheng HospitalThe Second Military Medical UniversityShanghai 200003China Department of Rheumatology and Clinical Immunology Peking University First HospitalBeijing 100034China Department of Rheumatology Huashan Hospital and Fudan UniversityShanghai 200040China

To the Editor:Ankylosing spondylitis(AS)is a chronic inflammatory disease that causes bony fusion of spine and sacroiliac joints,resulting in restricted spinal movement and *** China,the prevalence of AS is about 0.29%with a male to female ratio of approximately 3:1,and most cases occur in the adolescent period.[1]The misdiagnosis rate of AS patients in China is>50%.

关键词： spondylitis prevalence restricted

Cobalt-Catalyzed Switchable[4+1]and[4+1+1]Spirocyclization of Aromatic Amides with 2-Diazo-1H-indene-1,3(2H)-dione:Access to Spiro Indene-2,1'-isoindolinones and Spiro Isochroman-3,1'-isoindolinones

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Chinese Journal of Chemistry 2024年第4期42卷 363-369页

作者： Bin Li Mengmeng Xie Jingyu Li Nana Shen Xinying Zhang Xuesen fan State Key Laboratory of Antiviral Drugs Pingyuan LaboratoryKey Laboratory of Green Chemical Media and ReactionsKey Laboratory for Yellow River and Huai River Water Environmental Pollution ControlMinistry of EducationSchool of EnvironmentSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenan453007 China

Herein,we report a condition-controlled divergent synthesis of spiro indene-2,1'-isoindolinones and spiro isochroman-3,1'-isoindolinones through cobalt-catalyzed formal[4+1]and[4+1+1]spirocyclization of aromatic amides with 2-diazo-1H-indene-1,3(2H)-*** the reaction is carried out under air in ethyl acetate,spiro indene-2,1'-isoindolinones are formed through Co(II)-catalyzed C—H/N—H[4+1]*** the reaction is run under O2 in CH3CN,on the other hand,spiro isochroman-3,1'-isoindolinones are generated through Baeyer-Villiger oxidation of the in situ formed spiro indene-2,1'-isoindolinones with O2 as a cheaper and environmental-friendly oxygen *** general,these protocols have advantages such as using non-precious and earth-abundant metal catalyst,no extra additive,high efficiency and regioselectivity.A gram-scale synthesis and the removal of the directing group further highlight its utility.

关键词： Spiro indene-2,1'-isoindolinones Spiro isochroman-3,1'-isoindolinones 3d Transition metals Cobalt-catalyzed C-H Activation Switchable[4+1]and[4+1+1]spirocyclization Aromatic amides 2-Diazo-1H-indene-1,3(2H)-dione

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异烟肼对小鼠非特异性免疫功能的影响

陕西医学杂志 2004年第4期33卷 306-307,F003页

作者：毛泽善范雪辉马全祥宋向凤杨廷桐新乡医学院细胞生物教研室新乡453003

目的 :探讨异烟肼对小鼠免疫功能的影响。方法 :将 2 0只小鼠随机等分为对照组和实验组 ,对照组用清水喂食 ,实验组用 0 .5 mg/ml的异烟肼喂食 ,1 0 d后检测小鼠腹腔巨噬细胞内酸性磷酸酶活性的变化以及巨噬细胞吞噬功能的变化。结果 :... 详细信息

目的 :探讨异烟肼对小鼠免疫功能的影响。方法 :将 2 0只小鼠随机等分为对照组和实验组 ,对照组用清水喂食 ,实验组用 0 .5 mg/ml的异烟肼喂食 ,1 0 d后检测小鼠腹腔巨噬细胞内酸性磷酸酶活性的变化以及巨噬细胞吞噬功能的变化。结果 :与对照组相比 ,实验组小鼠腹腔巨噬细胞酸性磷酸酶活性增加 ,巨噬细胞的吞噬功能也有所增强。结论

关键词：异烟肼小鼠非特异性免疫功能药物作用酸性磷酸酶类