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Rheological Properties of Konjac Glucomannan/siO_2/Organic-Borate Gels

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Journal of Wuhan University of Technology(Materials Science) 2009年第4期24卷 575-580页

作者：吴力立张超灿 Department of Polymer Materials and Engineering School of Material Sciences and EngineeringWuhan University of Technology

A series of thermoreversible konjac glucomannan gels crosslinked by organic borate were prepared. Required amount of hydrophilic siO2 was added into the konjac glucomannan solutions before the crosslinking reaction, The gel network was formed through the crosslinking reaction between borate ions dissociated from organic borate and the cis-diol hydroxyl groups on the mannose units of polysaccharide chains. The rheological properties of the complex gels were studied by dynamic viscoelastic measurement. The gelation kinetics of the complex gels was studied and the critical getation points of the gels were exactly determined by the Winter-Chambon criterion. The effects of temperature and composite ratio on the shear storage modulus （G＇）, the loss modulus （G＂） and the sol-gel transition points were investigated.

关键词： konjac glucomannan si02 organic borate rheological properties

Preparation and properties of organic-inorganic modified siO_2 thin films

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Journal of Central South University 2013年第3期20卷 608-614页

作者：赵贤辉李长虹王海 School of Mechanical Electronic and Control EngineeringBeijing Jiaotong University

Polydimethylsiloxane(PDMS),tetraethoxysilane(TEOS),ethyl alcohol(EtOH) and deionized water were main raw materials to prepare silicone-modified hybrid thin films using sol-gel method.The effect of the contents of H2O and PDMS on thin films was studied.When the volume ratio of H2O to TEOS is 0.5,the optimum quality of thin films is obtained.And the gelation time is affected slightly by H2O content.Uniform thin films are obtained when the volume ratio of PDMS to TEOS is 0.2.Yet,the sol would be inactive in 6 d.Various properties of thin films were studied,including hardness,adhesive quality,hydrophobic property,corrosion protection property,and abrasion resistance.Test results show that the pencil hardness is generally 3-6 H,and adhesive quality achieves the highest standard of 0.When the sintering temperature is below 400 oC,the contact angle is about 95° and hydrophobic films are obtained.The abrasion resistance of thin films is better than that of aluminum alloy when the sintering temperature is higher than 300 oC.And the excellent corrosion protective effect is obtained by single-layer coating when the sintering temperature is higher than 400 oC.

关键词：腐蚀保护性能混合薄膜原料制备 si02 无机改性聚二甲基硅氧烷 TEOS 四乙氧基硅烷

Preparation of Cu-siO_2 composite aerogel by ambient drying and the influence of synthesizing conditions on the structure of the aerogel

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Chinese Science Bulletin 2011年第7期56卷 685-690页

作者： LI GuiAn, ZHU TingLiang, DENG ZhongXun, ZHANG YaJuan, JIAO Fei & ZHENG HaiRong College of Physics and Information Technology, Shaanxi Normal University, Xi’an 710062, China College of Physics and Information Technology Shaanxi Normal University Xi’an China

A copper-doped silica composite aerogel with high specific surface area was prepared using a sol-gel method at ambient pressure. A drying control chemical additive (DCCA) N,N-dimethylformamide (DMF) was introduced to the composite sol of tetraethyl orthosilicate (TEOS) and copper nitrate (Cu(NO3)2·3H2O) during the synthesizing process. The influence of the preparation conditions including Cu loading, catalyst concentration and heat treatment on the structure of copper-doped silica was investigated. The results showed that the obtained aerogel particles were uniformly distributed. The pore diameter was in a range of 2 to 15 nm. Heavier Cu loading benefited the formation of CuO crystalline, and reduced the specific surface area and pore diameter. When the catalyst concentration was high, the aggregation of si-O network was reduced with the increase of it. The composite aerogel exhibited a good thermal stability after the heat treatment at high temperature.

关键词：复合气凝胶铜掺杂凝胶结构合成条件 si02 常压正硅酸乙酯溶胶凝胶法

Preparation of BST nanocrystals embedded in siO_2 film by magnetron sputtering for nonvolatile memory applications

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Chinese Science Bulletin 2011年第11期56卷 1139-1141页

作者： WANG Li SUN HongFang ZHOU HuiHua ZHU Jing Beijing National Center for Electron Microscopy Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

We develop a method that uses magnetron sputtering to fabricate barium strontium titanate (BST) nanocrystals embedded in dielectric siO2 films.Transmission electron microscope images show that the BST nanocrystals have an average diameter of 5 nm and are well distributed in the siO2 film.In addition,we also analyze the BST nanocrystals composition deviation during the sputtering process by electron dispersive spectroscopy.

关键词： siO2薄膜纳米晶体磁控溅射 BST 嵌入式非易失性 si02 透射电子显微镜

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弱吸收多层薄膜消光系数的反演

物理学报 2005年第8期54卷 3722-3725页

作者：顾培夫陈海星郑臻荣刘旭浙江大学现代光学仪器国家重点实验室杭州310027

从窄带干涉滤光片的峰值透射率测量可以直接反演出弱吸收薄膜的消光系数,从而得到一种能简易而又精确地评价多层薄膜微弱吸收的新方法.推导了弱吸收窄带干涉滤光片的吸收表达式,阐述了确定弱吸收薄膜消光系数的基本原理.以离子束溅射的T... 详细信息

从窄带干涉滤光片的峰值透射率测量可以直接反演出弱吸收薄膜的消光系数,从而得到一种能简易而又精确地评价多层薄膜微弱吸收的新方法.推导了弱吸收窄带干涉滤光片的吸收表达式,阐述了确定弱吸收薄膜消光系数的基本原理.以离子束溅射的Ta2O5/siO2波分复用滤光片为例,分析了这种评价方法的基本精度.

关键词：消光系数多层薄膜弱吸收窄带干涉滤光片吸收薄膜 Ta2O5 离子束溅射直接反演波分复用 si02 基本原理评价方法透射率表达式

激光干涉结晶技术制备二维有序分布纳米硅阵列

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物理学报 2005年第8期54卷 3646-3650页

作者：邹和成乔峰吴良才黄信凡李鑫韩培高马忠元李伟陈坤基南京大学物理系固体微结构物理国家重点实验室南京210093

利用结合移相光栅掩模(PSGM)的激光结晶技术在超薄a-siNx/a-si:H/a-siNx三明治结构样品中制备出二维有序分布的纳米硅阵列.原始样品是用等离子体增强化学气相淀积法生长.a-si:H层厚为10nm,a-siNx为50nm,衬底材料为siO2/si或熔凝石英.原... 详细信息

利用结合移相光栅掩模(PSGM)的激光结晶技术在超薄a-siNx/a-si:H/a-siNx三明治结构样品中制备出二维有序分布的纳米硅阵列.原始样品是用等离子体增强化学气相淀积法生长.a-si:H层厚为10nm,a-siNx为50nm,衬底材料为siO2/si或熔凝石英.原子力显微镜、剖面透射电子显微镜、高分辨透射电子显微镜对样品表面形貌和微结构的观测结果表明,采用该方法可以在原始淀积的a-si:H层中得到位置可控的晶化区域:每个晶化区域直径约250nm,具有同PSGM一致的2μm周期;晶化区域内形成的纳米硅颗粒尺寸接近原始淀积的a-si:H层厚,且晶粒的择优取向为.

关键词：结晶技术纳米硅激光干涉阵列分布有序二维制备高分辨透射电子显微镜化学气相淀积法等离子体增强 siNx 原子力显微镜三明治结构晶化区 si02 衬底材料观测结果表面形貌颗粒尺寸择优取向样品原始微结构

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非超临界干燥法制备siO_2气凝胶

物理化学学报 2003年第6期19卷 504-508页

作者：甘礼华陈龙武张宇星同济大学化学系上海200092

应用廉价的国产硅溶胶为原料,通过凝胶过程和干燥过程条件的选择,以非超临界干燥技术最终获得了块状siO2气凝胶.该气凝胶外观状态与应用正硅酸乙酯为原料制得的完全一致,其微观结构也相当良好,其直径和孔分布均匀.溶液的配比和pH对凝胶... 详细信息

应用廉价的国产硅溶胶为原料,通过凝胶过程和干燥过程条件的选择,以非超临界干燥技术最终获得了块状siO2气凝胶.该气凝胶外观状态与应用正硅酸乙酯为原料制得的完全一致,其微观结构也相当良好,其直径和孔分布均匀.溶液的配比和pH对凝胶过程和气凝胶样品的密度有比较明显的影响,同时pH值与siO2的粒径之间也有一定的关系.依据制备条件的变化,所得siO2气凝胶的密度约在200～400kg·m-3,比表面在250～300m2·g-1之间变化,平均孔径约为11～20nm,而孔隙率在91%左右.

关键词：气凝胶非超临界干燥 si02 硅溶胶制备轻质纳米多孔材料正硅酸甲酯溶胶-凝胶

化学机械抛光工艺参数对氧化锆陶瓷抛光速率的影响

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表面技术 2018年第9期47卷 266-271页

作者：王光灵刘卫丽刘宇翔孔慧霍军朝宋志棠中国科学院上海微系统与信息技术研究所信息功能材料国家重点实验室上海200050 中国科学院大学北京100049

目的探究siO_2磨料固含量、抛光垫和下压力等工艺参数对氧化锆陶瓷化学机械抛光速率的影响和作用机理。方法采用粒径为80 nm的钠型稳定型硅溶胶,氢氧化钠溶液作为pH调节剂,将硅溶胶pH调至为10。通过CP-4抛光设备进行氧化锆陶瓷抛光实验... 详细信息

目的探究siO_2磨料固含量、抛光垫和下压力等工艺参数对氧化锆陶瓷化学机械抛光速率的影响和作用机理。方法采用粒径为80 nm的钠型稳定型硅溶胶,氢氧化钠溶液作为pH调节剂,将硅溶胶pH调至为10。通过CP-4抛光设备进行氧化锆陶瓷抛光实验及摩擦系数采集,采用黏度测试仪测试不同固含量硅溶胶的黏度,采用扫描电子显微镜分析了SUBA系列两种抛光垫的微观结构。结果硅溶胶固含量为37%时,抛光速率最快,达到54.3 nm/min,此时摩擦系数最小,为0.1501。随着固含量的增加,摩擦系数小幅增加,并稳定在0.1540附近。硅溶胶固含量高于37%的抛光机制是流体力学作用的结果,固含量低于37%的抛光机制是流体力学和机械力共同作用的结果。扫描电镜下观察发现,SUBA800抛光垫的孔隙尺寸比SUBA600抛光垫的孔隙尺寸小,使用前者的抛光速率快于后者,抛光速率相差10 nm/min。因为孔隙多改变了硅溶胶和抛光垫的接触机制,增大了切应力和摩擦系数,机械作用力加强,从而加快了抛光速率。摩擦系数与下压力没有关系,下压力小于3.5 psi时,抛光速率符合Preston方程。结论对氧化锆陶瓷进行化学机械抛光处理,固含量在37%时,抛光速率最快。SUBA800抛光垫相比SUBA600抛光垫,更适合氧化锆陶瓷抛光。下压力小于3.5 psi时,抛光速率符合Preston方程行为,且摩擦系数和下压力没有关系。

关键词：化学机械抛光氧化锆陶瓷 si02 抛光机理抛光垫固含量

Low temperature soldering alloy using Sn63 Pb37 implantation of silica ceramics and copper solder assisted by ion and deposition

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China Welding 2012年第3期21卷 38-43页

作者：徐睦忠田修波巩春志杨波杨士勤 State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin150001

Copper ion implantation and deposition technique was applied as a pretreatment method for low temperature joining of silica ceramic （ siO2 ） and copper alloy. The effect of copper ion implantation and deposition parameters on the microstructures and mechanical behavior of the soldering joints was investigated by scanning electron microscope （SEM） , X- ray diffraction （ XRD ） and shearing test. The copper implantation depth was about 90 nm with peak concentration of 70% for the siO2 sample implanted for 90 rain. If copper film was deposited for 4 rain using magnetron sputtering, copper layer with thickness of 150 nm and peak concentration of 80% was obtained. After pretreatment of ion implantation and deposition, siO2 and copper were joined successfully at low temperature directly using SnPb solder. The SnPb solder filling ratio along joining seams was up to 100% without defects with smooth soldering toes. With the increase of implantation dose, the shear strength of the si02/Cu joints increases accordingly. After a special pretreatment on siO2 （ Cu implantation for 30min, following Cu deposition for 4 rain, then Cu implantation for 60 rain and finally Cu deposition for 120 min） , a maximum soldering strength of 22 MPa was achieved, and the soldering joints fractured at the siO2 base material.

关键词： ion implantation and deposition si02 copper low temperature soldering