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Fracture Mechanism of 3D, Five-directional Braided (SiO_2)_f /SiO_2 Composites Prepared by Silicasol-infiltration-sintering Method 认领 引用 被引量:1
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作者 李斌斌 ZHU Jianxun +2 位作者 LIN Long LIU Yong CHEN Zhaofeng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第2期355-357,共3页
Three-dimensional (3D) five-directional braided (SiO2)/SiO2 composites were prepared by silicasol-infiltration-sintering (SIS) method. The flexural properties and microstructures were studied. The flexural stren... Three-dimensional (3D) five-directional braided (SiO2)/SiO2 composites were prepared by silicasol-infiltration-sintering (SIS) method. The flexural properties and microstructures were studied. The flexural strength and flexural elastic modulus were found to be 73 MPa and 12 GPa, respectively. The results of stress vs deflection curve and SEM examinations revealed that the fracture mechanism of 3D, five-directional braided (SiO2)/SiO2 composite was a mixture mode of ductile and brittle. The ductile mode was attributed to the weak bonding strength of fiber/matrix at low temperature. The brittle fracture might be caused by the propagation of micro defect or crack, which existed in the as-prepared composites for the ten-cycle process. 展开更多
关键词 fracture mechanism 3D five-directional (SiO2)y/SiO2 composite silicasol-infiltrationsintering method
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二陈汤通过Nrf2/HO-1信号通路调节氧化应激和代谢紊乱改善SiO2诱导的肺损伤 认领 引用
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作者 芦俊 朱馨怡 +6 位作者 刘子怡 胡吉霞 陈佳露 肖荣 王智槟 刘畅 卢芳国 《中国实验方剂学杂志》 CAS CSCD 北大核心 2026年第13期32-42,共11页
目的:观察二陈汤对二氧化硅(SiO2)诱导肺损伤大鼠的保护作用,探讨其作用机制。方法:采用一次性气管滴注50 g·L-1 SiO2混悬液建立肺损伤大鼠模型。将30只雄性SD大鼠随机分为正常组,模型组,二陈汤低、高剂量组(4.5、9 g·k... 目的:观察二陈汤对二氧化硅(SiO2)诱导肺损伤大鼠的保护作用,探讨其作用机制。方法:采用一次性气管滴注50 g·L-1 SiO2混悬液建立肺损伤大鼠模型。将30只雄性SD大鼠随机分为正常组,模型组,二陈汤低、高剂量组(4.5、9 g·kg-1·d-1)和地塞米松组(0.2 mg·kg-1·d-1),连续干预4周。苏木素-伊红(HE)染色观察肺组织病理变化;生化法检测肺组织丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GPX)水平;实时荧光定量聚合酶链式反应(Real-time PCR)、蛋白免疫印迹法(Western blot)及免疫荧光法检测核因子E2相关因子2(Nrf2)/血红素加氧酶-1(HO-1)信号通路关键分子的表达。超高效液相色谱-串联质谱法(UPLC-MS/MS)鉴定二陈汤主要活性成分,结合分子对接技术评估其核心成分与Nrf2/HO-1的结合能力。超高效液相色谱-四极杆-飞行时间质谱法(UPLC-Q-TOF-MS)非靶向代谢组学技术分析肺组织代谢谱,相关性分析筛选与Nrf2/HO-1信号通路密切相关的差异代谢物及指标。结果:与正常组比较,模型组大鼠体质量增长率显著降低,肺指数显著升高,肺组织MDA含量显著升高,SOD和GPX活性明显降低,Nrf2 mRNA及蛋白表达明显降低,HO-1、GPX4蛋白表达明显降低,Kelch样ECH关联蛋白1(Keap1)蛋白明显升高(P<0.05,P<0.01)。与模型组比较,二陈汤明显减缓SiO2诱导的大鼠体质量下降趋势(P<0.05);减轻大鼠肺泡炎性细胞浸润和矽结节形成;降低肺组织MDA含量,提高SOD和GPX活性(P<0.05,P<0.01)。UPLC-MS/MS和分子对接结果显示橙皮苷、甘草酸等二陈汤核心成分与Nrf2/HO-1具有强结合亲和力;分子生物学实验表明二陈汤可促进Nrf2核转位,上调HO-1、GPX4 mRNA及蛋白表达,下调Keap1表达(P<0.05,P<0.01)。代谢组学结果显示,二陈汤可回调SiO2诱导的亚油酸、谷氨酰胺等代谢物异常表达(P<0.05,P<0.01)。相关性分析表明,Nrf2、HO-1与SOD、GPX呈明显正相关(P<0.05,P<0.01),与谷氨酰胺、丝氨酸呈明显负相关(P<0.05,P<0.01)。结论:二陈汤可能通过核心成分激活Nrf2/HO-1信号通路,调节氧化应激及代谢紊乱,从而改善SiO2诱导的大鼠肺损伤,为防治职业性肺损伤提供实验依据。 展开更多
关键词 二陈汤 二氧化硅(SiO2) 肺损伤 核因子E2相关因子2(Nrf2)/血红素加氧酶-1(HO-1)信号通路 氧化应激 代谢紊乱
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Effect of boron doping on waterproof and dielectric properties of polyborosiloxane coating on SiO2f/SiO2 composites 认领 引用 被引量:8
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作者 Long XIA Siru LU +7 位作者 Bo ZHONG Longnan HUANG Hua YANG Tao ZHANG Haibo HAN Pan WANG Li XIONG Guangwu WEN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第8期2017-2027,共11页
A hydrophobic coating of the silica fiber reinforced silica composites(SiO2f/SiO2) was synthesized by sol-gel method using methyltriethoxy-silane(MTES) and boric acid(B(OH)3) as raw materials. The relationship among b... A hydrophobic coating of the silica fiber reinforced silica composites(SiO2f/SiO2) was synthesized by sol-gel method using methyltriethoxy-silane(MTES) and boric acid(B(OH)3) as raw materials. The relationship among boron doping, chemical structure of precursors and durability of hydrophobic coatings was discussed. The Si-O-B and methyl groups were successfully introduced in the gel precursors according to the FT-IR and XPS results. The resins were filled in the internal and surface holes of the SiO2f/SiO2 composites partially or completely, which is beneficial to reduce the physical adsorption of the moisture. In addition, hydroxyl groups of the SiO2f/SiO2 composites reacted with the resins and hydrophobic methyl groups were introduced, leading to the reduction of the chemical adsorption of water. Also, the boron doping was beneficial to enhancing the physical cross-linking between the coating and the SiO2f/SiO2 composites, and improved the adhesion of the coating to the substrate. The results show that the optimal hydrophobic coating with contact angle 130.33°, moisture absorption 0.33% and adhesion level 1 is obtained when the molar ratio of MTES to B(OH)3 is 10:4. The real permittivity of M10B4 is constant in the range of 2.32–2.51 and the dielectric tangent loss is constant in the range of 5.5 × 10-4–8.7 × 10-3. The hydrophobic coating has excellent dielectric properties. 展开更多
关键词 Adhesion Dielectric Hydrophobic Polyborosiloxane SiO2f/SiO2 composites
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考虑纳米SiO2颗粒作用的Cu-SiO2-Cu接触界面摩擦性能研究 认领 引用
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作者 马金兰 张肖 +2 位作者 佟瑞庭 张皓宸 张润成 《表面技术》 EI CAS CSCD 北大核心 2026年第13期99-110,共12页
目的为揭示空间尘埃环境纳米SiO2颗粒侵入软金属接触界面后的摩擦机理,本文系统研究了颗粒尺寸、形貌等因素对接触界面摩擦行为的影响,为空间机构Cu润滑膜的设计与防护提供理论依据。方法采用分子动力学方法构建Cu-SiO2-Cu三体纳... 目的为揭示空间尘埃环境纳米SiO2颗粒侵入软金属接触界面后的摩擦机理,本文系统研究了颗粒尺寸、形貌等因素对接触界面摩擦行为的影响,为空间机构Cu润滑膜的设计与防护提供理论依据。方法采用分子动力学方法构建Cu-SiO2-Cu三体纳米接触模型,将Cu视为比较厚的软金属润滑膜,引入不同形貌的SiO2颗粒,在不同条件下开展研究。结果颗粒尺度对界面摩擦具有显著的尺寸效应,当颗粒半径为1nm时,强黏附与局部变形导致平均摩擦力最高;随着颗粒半径增大至2nm,滚动作用增强,摩擦力降低;当继续增大颗粒尺寸时,接触面积增大、滚动被抑制,摩擦力开始回升。下压深度增加会导致接触区塑性变形与犁削作用增强,使摩擦力大幅度上升。滑动速度对摩擦力的影响表现出先减小后增大的特征。相较于光滑球形颗粒,具有表面凸起的近球形颗粒在接触表面会产生更强的应力集中与犁沟效应,并伴随温度急剧上升,导致摩擦水平进一步增加。结论SiO2颗粒作为第三体时,对于颗粒适中且表面平滑的情况,体系可形成滚-滑混合运动并表现出“纳米轴承效应”;颗粒过小或形貌尖锐时,黏附与犁沟共同主导摩擦,能量耗散加剧;过大尺寸、过大下压深度以及过高滑动速度则通过几何约束、剪切集中和热效应使摩擦力升高。 展开更多
关键词 分子动力学 SiO颗粒 Cu-SiO2-Cu 三体接触 滑动接触
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TiO2-Ag双功能涂层协同修饰的SiO基复合负极材料制备及高容量锂离子存储性能研究 认领 引用
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作者 吴霞 张海燕 洪浩群 《新能源进展》 CSCD 北大核心 2026年第2期167-175,共9页
为满足锂离子电池领域对高容量、长寿命储能技术的迫切需求,硅基负极材料因其高理论容量优势成为产业化应用研究的重点。然而,硅(Si)在锂化过程中严重的体积膨胀制约了其应用。与Si相比,一氧化硅(SiO)的体积膨胀虽有所降低,但仍存在本... 为满足锂离子电池领域对高容量、长寿命储能技术的迫切需求,硅基负极材料因其高理论容量优势成为产业化应用研究的重点。然而,硅(Si)在锂化过程中严重的体积膨胀制约了其应用。与Si相比,一氧化硅(SiO)的体积膨胀虽有所降低,但仍存在本征电导率低和初始库仑效率低等问题。为解决SiO材料的缺陷,采用二氧化钛(TiO2)和银(Ag)双功能涂层修饰策略,通过球磨法和溶胶凝胶法制备了TiO2和Ag双涂层修饰的SiO基复合材料(D-SiO@TiO2@Ag)。电化学测试表明,在0.2 A/g电流密度下,该复合材料经过100次循环后可逆容量为1164.3 mA·h/g,容量保持率为73.29%,显著高于未修饰SiO的547.9 mA·h/g和34.16%。D-SiO@TiO2@Ag复合材料结合了SiO的高容量和TiO2的缓解体积膨胀优势,同时通过Ag纳米颗粒提升了导电性和电荷传输性能,为新一代高容量、高稳定性的硅基负极材料提供了设计思路。 展开更多
关键词 纳米复合材料 锂离子电池 硅基负极 银纳米颗粒 SiO TiO2
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A phase inversion based sponge-like polysulfonamide/SiO_2 composite separator for high performance lithium-ion batteries 认领 引用 被引量:8
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作者 Xiao Wang Gaojie Xu +5 位作者 Qingfu Wang Chenglong Lu Chengzhong Zong Jianjun Zhang Liping Yue Guanglei Cui 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第6期1292-1299,共8页
In this work,a sponge-like polysulfonamide(PSA)/SiO_2 composite membrane is unprecedentedly prepared by the phase inversion method,and successfully demonstrated as a novel separator of lithium-ion batteries(LIBs).Comp... In this work,a sponge-like polysulfonamide(PSA)/SiO_2 composite membrane is unprecedentedly prepared by the phase inversion method,and successfully demonstrated as a novel separator of lithium-ion batteries(LIBs).Compared to the commercial polypropylene(PP) separator,the sponge-like PSA/SiO_2 composite possesses better physical and electrochemical properties,such as higher porosity,ionic conductivity,thermal stability and flame retarding ability.The LiCoO_2/Li half-cells using the sponge-like composite separator demonstrate superior rate capability and cyclability over those using the commercial PP separator.Moreover,the sponge-like composite separator can ensure the normal operation of LiCoO_2/Li half-cell at an extremely high temperature of 90 °C,while the commercial PP separator cannot.All these encouraging results suggest that this phase inversion based sponge-like PSA/SiO_2 composite separator is really a promising separator for high performance LIBs. 展开更多
关键词 Polysulfonamide/SiO2 composite Phase inversion method Separator Performance enhancement Lithium-ion battery
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Mechanical properties and in situ fracture behavior of SiO2f/phosphate geopolymer composites 认领 引用 被引量:2
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作者 Chang-Qing Yu You-Ran Yu +4 位作者 Ying-Min Zhao Pei-Gang He Chang-Shou Xu Shuai Fu Zhi-Hua Yang 《Rare Metals》 SCIE EI CAS CSCD 2020年第5期562-569,共8页
Geopolymers,such as phosphate-based geopolymer,are promising materials that have drawn extensive attentions as wave-transparent candidates with low dielectric loss factor.In this paper,multilayer SiO2fibers are introd... Geopolymers,such as phosphate-based geopolymer,are promising materials that have drawn extensive attentions as wave-transparent candidates with low dielectric loss factor.In this paper,multilayer SiO2fibers are introduced into phosphate-based geopolymer matrix to prepare composites.Crack generation and fracture behaviors during the three-point bending tests in as-prepared SiO2f/phosphate geopolymer composites are clarified by in situ observation Before high-temperature treatment,composite with 17 vol%fiber content exhibits the best mechanical properties.A decreasing mechanical strength is observed after being treated at higher temperature,which is attributed to the stronger interface binging between fibers and phosphatebased geopolymer matrix.Most importantly,the presence of SiO2fibers can strengthen mechanical properties of phosphate-based geopolymer matrix but shows negligible impact on its dielectric properties,achieving dielectric loss factor as low as 3.53910-3after being treated at 700°C. 展开更多
关键词 Phosphate-based geopolymer SiO2 fibber In situ observation Fracture behavior Dielectric properties
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Concentration and annealing effect on PL properties of sol-gel derived SiO_2-Y_2O_3:Eu3+ nanocomposites 认领 引用 被引量:2
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作者 王忆 曾庆光 +3 位作者 胡社军 吴坤彬 蒋俊宏 陈根廷 《Journal of Rare Earths》 SCIE EI CAS 2010年第2期176-180,共5页
An improved sol-gel method was employed to prepare Eu3+ ions doped SiO2-Y2O3 nanocomposites.Systematic study was carried out on the effect of post-annealing treatment on photoluminescence(PL) properties of the samples... An improved sol-gel method was employed to prepare Eu3+ ions doped SiO2-Y2O3 nanocomposites.Systematic study was carried out on the effect of post-annealing treatment on photoluminescence(PL) properties of the samples under various europium ions doping concentrations.X-ray diffraction(XRD) patterns indicated that the samples showed an amorphous matrix structure,and the scanning electron microscopy(SEM) pictures showed that the samples presented a nano size(from 21 to 42 nm) granular-stack structure after hi... 展开更多
关键词 Eu3+doped SiO2-Y2O3 glass photoluminescence(PL) nanocomposites rare earths
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Effect of catalyst on structure of(PEO)_8LiClO_4-SiO_2 composite polymer electrolyte films 认领 引用 被引量:3
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作者 潘春跃 张倩 +2 位作者 冯庆 高金环 赵悠曼 《Journal of Central South University of Technology》 2008年第4期438-442,共5页
(PEO)8LiClO4-SiO2 composite polymer electrolytes(CPEs)were prepared by in-situ reaction,in which ethyl-orthosilicate(TEOS)was catalyzed by HCl and NH3.H2O,respectively.The ionic conductivity,the contact angle and the ... (PEO)8LiClO4-SiO2 composite polymer electrolytes(CPEs)were prepared by in-situ reaction,in which ethyl-orthosilicate(TEOS)was catalyzed by HCl and NH3.H2O,respectively.The ionic conductivity,the contact angle and the morphology of inorganic particles in the CPEs were investigated by AC impedance spectra,contact angle method and TEM.The conductivities of acid-catalyzed CPE and alkali-catalyzed CPE are 2.2×10-5and 1.1×10-5S/cm respectively at 30℃.The results imply that the catalyst plays an important role in the structure of in-situ preparation of SiO2,and influences the surface energy and conductivity of CPE films directly.Meanwhile,the ionic conductivity is related to the surface energy. 展开更多
关键词 PEO(polyethylene oxide) SiO2 composite polymer electrolyte conductivity catalytic reaction
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丝胶蛋白/SiO2纳米复合溶胶对芳纶服用性能的影响 认领 引用
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作者 田恬 尉霞 +3 位作者 康青青 罗璟娴 王庆博 刘阳 《纺织科技进展》 CAS 2026年第1期27-30,共4页
为解决芳纶织物服用性能不足的问题,制备丝胶蛋白/SiO2纳米复合溶胶并将其整理到间位芳纶上,研制出不同复合溶胶的织物试样,并探究复合溶胶浓度对芳纶织物服用性能的影响。结果表明,当复合溶胶浓度为4%时,整理后织物的各项性能较好。在... 为解决芳纶织物服用性能不足的问题,制备丝胶蛋白/SiO2纳米复合溶胶并将其整理到间位芳纶上,研制出不同复合溶胶的织物试样,并探究复合溶胶浓度对芳纶织物服用性能的影响。结果表明,当复合溶胶浓度为4%时,整理后织物的各项性能较好。在最优整理条件(浓度4%)下,间位芳纶的回潮率、导湿性、抗静电性及透湿性均有所改善,而透气性略微下降,总体而言,芳纶织物的服用性能得到改善。 展开更多
关键词 丝胶蛋白/SiO2纳米复合溶胶 间位芳纶 服用性能
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Construction of SiO2-TiO2/g-C3N4 composite photocatalyst for hydrogen production and pollutant degradation: Insight into the effect of SiO2 认领 引用 被引量:1
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作者 Sijia Sun Hao Ding +5 位作者 Lefu Mei Ying Chen Qiang Hao Wanting Chen Zhuoqun Xu Daimei Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第9期2287-2294,共8页
Using low-cost precipitated silica(SiO2) as the carrier,a ternary SiO2-TiO2/g-C3N4 composite photocatalyst was prepared via the sol-gel method associated with a wet-grinding process.The asprepared composite exhibits p... Using low-cost precipitated silica(SiO2) as the carrier,a ternary SiO2-TiO2/g-C3N4 composite photocatalyst was prepared via the sol-gel method associated with a wet-grinding process.The asprepared composite exhibits photocatalytic hydrogen production and pollutant degradation performance under solar-like irradiation.The effect of SiO2 carrier on the properties of the heterostructure between TiO2 and g-C3N4(CN) was systematically studied.It is found that SiO2 has important effects on promoting the interaction between TiO2 and CN.The particle size of TiO2 and CN was obviously reduced during the calcination process due to the effects of SiO2.Especially,the TiO2 particles exhibit monodispersed state with particle size below 10 nm(quantum dots),resulting in the improvement of the contact area and the interaction betweenTiO2 and CN,and leading to the formation of efficient TiO2/CN Zscheme heterostructure in SiO2-TiO2/CN.Besides,the introduction of SiO2 can increase the specific surface area and light absorption of SiO2-TiO2/CN,further promoting the photocatalytic reaction.As expected,the optimum SiO2-TiO2/CN composite exhibits 12.3,3.1 and 2.9 times higher photocatalytic hydrogen production rate than that of SiO2-TiO2,CN and TiO2/CN under solar-like irradiation,while the photocatalytic active component in SiO2-TiO2/CN is only about 60 wt%.Moreover,the rhodamine B degradation rate of SiO2-TiO2/CN is also higher than that of SiO2-TiO2,CN and TiO2/CN. 展开更多
关键词 SiO2 carrier Heterostructure Photocatalyst g-C3N4 TiO2
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Nafion/SiO_2 Nanocomposites:High Potential Catalysts for Alkylation of Benzene with Linear C_9-C13 Alkenes 认领 引用 被引量:4
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作者 HaiWANG MingHanHAN 《Chinese Chemical Letters》 SCIE CAS 2002年第11期1121-1124,共4页
High surface area Nafion/SiO2 nanocomposites with nano-sized Nafion resin particles entrapped and dispersed within the highly porous silica matrix exhibited significantly enhanced activity, high selectivity and long-t... High surface area Nafion/SiO2 nanocomposites with nano-sized Nafion resin particles entrapped and dispersed within the highly porous silica matrix exhibited significantly enhanced activity, high selectivity and long-term stability for the alkylation of benzene with linear C9-C13 alkenes owing to the increased accessibility of Nafion resin-based acid sites to reactants. 展开更多
关键词 Nafion/SiO2 nanocomposites Friedel-Crafts alkylation linear alkylbenzenes.
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Grain Size and Wettability of TiO_2/SiO_2 Photocatalytic Composite Thin Filing 认领 引用 被引量:12
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作者 Jiaguo Yu, Xiujian Zhao, Jimmy C Yu, Jun Lin (State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China Deportment of Chemised The Chinese University of Hong Kong, Hong Kong, 《Rare Metals》 SCIE EI CAS 2001年第2期81-86,共6页
The uniform transparent TiO2/SiO2 photocatalytic composite thin films are prepared by sol-gel method on the soda lime glass substrates, and characterized by UV-visible spectroscopy, X-ray diffraction (XRD), transmissi... The uniform transparent TiO2/SiO2 photocatalytic composite thin films are prepared by sol-gel method on the soda lime glass substrates, and characterized by UV-visible spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), BET surface area, FTIR spectroscopy and X-ray photoelectron spectroscopy (XPS). It was found that the addition of SiO2 to TiO2 thin films can suppress the grain growth of TiO2 crystal, increase the hydroxyl content on the surface of TiO2 films, lower the contact angle for water on TiO, films and enhance the hydrophilic property of TiO2 films. The super-hydrophilic TiO2/SiO2 photocatalytic composite thin films with the contact angle of 0((o) under bar) are obtained by the addition of 10%-20% SiO2 in mole fraction. 展开更多
关键词 sol-gel method TiO2/SiO2 photocatalytic composite thin films grain size wettability
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Structural Characteristics and Photocatalytic Activity of Ambient Pressure Dried SiO2/TiO2 Aerogel Composites by One-step Solvent Exchange/Surface Modification 认领 引用 被引量:3
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作者 徐海珣 朱平华 +2 位作者 WANG Lijiu JIANG Zuqiang 赵善宇 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第1期80-86,共7页
An ambient pressure synthesis of SiO2/TiO2 binary aerogel was prepared through the low-cost precursors of titanium tetrachloride(TiCl4) and sodium silicate(Na2O·nSiO2).After gelation,solvent exchange and surf... An ambient pressure synthesis of SiO2/TiO2 binary aerogel was prepared through the low-cost precursors of titanium tetrachloride(TiCl4) and sodium silicate(Na2O·nSiO2).After gelation,solvent exchange and surface modification were performed simultaneously and the modified gel was finally dried under ambient pressure.Microstructural analyses by transmission electron microscope(TEM) indicate that fabricated SiO2/TiO2 aerogel composite shows similar sponge-like nanostructure as silica aerogel,and the Brunauer-EmmettTeller(BET) analysis shows that the specific surface area of the composite reaches 605 m^2/g,and the average pore size is 9.7 nm.Such binary aerogel exhibits significant photocatalytic performance in this paper for treating model pollutant of methyl orange(MO),and the decolorizing efficiency of MO is detected as 84.9%after 210 mins exposure to UV light irradiation.Degraded gel suspends in the water so as to separate from solution for reuse,and after 4 times recycling,70%degradation efficiency can be easily reached when composite catalyzed system is exposed for 210 mins under UV irradiation. 展开更多
关键词 photocatalytic activity water glass SiO2/TiO2 binary aerogel ambient drying
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Synthesis of CdTe/SiO2Composites and Their Fluorescence Properties 认领 引用 被引量:1
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作者 WANG Mei-ping LIN Jin-hui SHAN Chuan-sheng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第4期540-542,共3页
Thioglycolic acid(TGA)-stabilized CdTe nanocrystals(NCs)were prepared with sodium tellurite as tellurium source,which avoids the cumbersome processes associated with H2Te or NaHTe sources.Fluorescent CdTe/SiO2 composi... Thioglycolic acid(TGA)-stabilized CdTe nanocrystals(NCs)were prepared with sodium tellurite as tellurium source,which avoids the cumbersome processes associated with H2Te or NaHTe sources.Fluorescent CdTe/SiO2 composites were synthesized by a sol-gel method without the exchange of surface ligands.The phase structure of CdTe NCs was investigated by X-ray diffractometry.For comparison,some characterizations were done for both the CdTe NCs and the composites.CdTe NCs and CdTe/SiO2 composites were characterized with TEM,digital camera and fluorescence spectrophotometer.The stability of CdTe NCs and the composites were investigated in phosphate-buffered saline(PBS)buffer and the fluorescent properties of the composites were discussed in detail. 展开更多
关键词 CdTe nanocrystal Sodium tellurite CdTe/SiO2
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Surface modification of LiCo0.05Mn1.95O_4 cathode by coating with SiO_2-TiO_2 composite 认领 引用 被引量:1
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作者 禹筱元 胡国荣 +3 位作者 彭忠东 肖劲 陈召勇 刘业翔 《中国有色金属学会会刊:英文版》 2004年第4期723-727,共5页
The cycling characteristics and low specific capacity of LiMn2O4 have always been the greatest obstacle to its commercialization. For the improvement of cyc le performance,the surface of LiCo0.05Mn1.95O4 was coated wi... The cycling characteristics and low specific capacity of LiMn2O4 have always been the greatest obstacle to its commercialization. For the improvement of cyc le performance,the surface of LiCo0.05Mn1.95O4 was coated with ve ry fine SiO2-TiO2 composite prepared by sol-gel method. The structure and morphology of the coating materials were investigated by X-ray diffraction (XRD ) and scanning electron microscope (SEM). The electrochemical performances of un coated and SiO2-TiO2 coated LiCo0.05Mn1.95O4 spinel at 25 ℃ and 55 ℃ were studied with a voltage range of 3.04.35V and a current density of 0.1 mA/cm2. There is a slight decrease in the initial discharge ca pacity of coated LiCo0.05Mn1.95O4(119 mA·h/g) compared with that of uncoated (123 mA·h/g). However the cycle ability of LiCo0.05Mn1. 95O4 coated by SiO2-TiO2 is improved. It is proposed that surface treat ment is an effective method to improve the cycle performance of LiCo0.05Mn 1.95O4. The surface modification is successful in minimizing the harmful side reactions within the batteries by placing a protective barrier layer betwe en the oxidizing cathode material and the liquid electrolyte. 展开更多
关键词 SiO2-TiO2 复合涂层 表面改性 LiCo0.05Mn1.95O4 锂离子电池 电极材料
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DEFORMATION INVESTIGATION ON iPP/SiO_2 COMPOSITES: INFLUENCE OF STRETCHING TEMPERATURE AND PARTICLE SIZE ON MORPHOLOGY EVOLUTION AND CRYSTALLINE STRUCTURE OF THIN FILMS 认领 引用
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作者 Xiu-qin Zhang Qian Xing +2 位作者 Rong-bo Li 王锐 Du-jin Wang 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2013年第2期275-284,共10页
In the present work, structure changes during (SiO2) composites have been investigated systematically stretching of isotactic polypropylene (iPP) and iPP/silicon dioxide The or-form crystal structure of both iPP a... In the present work, structure changes during (SiO2) composites have been investigated systematically stretching of isotactic polypropylene (iPP) and iPP/silicon dioxide The or-form crystal structure of both iPP and iPP/SiO2 composites is destroyed and transforms into the mesophase as the samples are stretched at a low temperature (35℃), while stretching at high temperatures (90℃ and 120℃) can restrain the appearance of defects and keep the perfection of crystal structure. FTIR results reveal that the stretching temperatures show no obvious difference of the effect on the orientation of pure iPP, however, the orientation of iPP/SiO2 composites is greatly changed by the tensile temperature. In the case of micron-sized SiO2 particles (average particle diameter d 〉 1 μm), the orientation of the composites is lower than that of pure iPP at all stretching temperatures. The above results suggest that the stretching temperature and the SiO2 particle size have great influence on the structure variation and orientation behavior of iPP/SiO2 composites. 展开更多
关键词 iPP/SiO2 composites Stretching Morphology Structure variation.
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Photocatalytic and Thermal Insulating Performances of Fiber Reinforced Hierarchical TiO_2/SiO_2 Xerogel Composites Synthesized by Ambient Drying Route 认领 引用
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作者 徐海珣 赵善宇 +2 位作者 郑猛 贾佳佳 朱平华 《Journal of Donghua University(English Edition)》 CAS 2017年第4期570-576,共7页
Silica( SiO_2) based aerogel/xerogel materials have been received ever-growing attentions for versatile applications. However,the widespread applications are narrowed by the inert properties,fragile and brittle nature... Silica( SiO_2) based aerogel/xerogel materials have been received ever-growing attentions for versatile applications. However,the widespread applications are narrowed by the inert properties,fragile and brittle natureof silica materials and cumbersome preparation processes. In this paper,titania( TiO_2) was introduced into SiO_2 matrix to form photocatalytic hybrid gels. The TiO_2/SiO_2 composites were then reinforced by the impregnation of various fibrillary reinforcements,such as glass,mullite mineral and ceramic fibers. The properties of the composites were studied systematically in terms of fiberstability,microstructure,chemical interaction and thermal conductivity. The final xerogel composites displayed improved monolithic geometry,satisfied thermal conductivity(0. 09-0. 25 W·m-1·K-1) and optimized photocatalytic performance(85% removal of model pollutant of methyl orange( Mo)),which could be expected to be a feasible route to multi-functional building facades in the future. 展开更多
关键词 titania-silica(TiO2/SiO2) composite photocatalytic thermal conductivity fiber reinforcement
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SiO 2气凝胶复合材料的低温常压制备与节能性能研究 认领 引用
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作者 王婷 赵宝宝 白硕 《功能材料》 CAS CSCD 北大核心 2026年第7期170-178,共9页
以正硅酸乙酯(TEOS)和甲基三乙氧基硅烷(MTES)为共前驱体,采用酸碱两步溶胶-凝胶法结合常压干燥工艺,制备了疏水改性SiO 2气凝胶复合材料,系统研究了TEOS与MTES摩尔比(8∶2、6∶4、4∶6、2∶8)对气凝胶化学结构、微观形貌、孔结构、疏... 以正硅酸乙酯(TEOS)和甲基三乙氧基硅烷(MTES)为共前驱体,采用酸碱两步溶胶-凝胶法结合常压干燥工艺,制备了疏水改性SiO 2气凝胶复合材料,系统研究了TEOS与MTES摩尔比(8∶2、6∶4、4∶6、2∶8)对气凝胶化学结构、微观形貌、孔结构、疏水性能、热稳定性、力学性能及导热性能的影响。结果表明,MTES成功以Si—CH3形式接枝于气凝胶骨架,实现由亲水向疏水的转变。当n(TEOS)∶n(MTES)=4∶6时,SiO 2气凝胶复合材料的综合性能最优,其接触角达141.8°、比表面积为678 m2/g、孔容为1.82 cm 3/g、平均孔径为10.7 nm、抗压强度达1.12 MPa、最大变形量为16.5%、密度为0.020 g/cm 3、导热系数低至0.15 W/(m·K),较未改性样品降低50%。同时,其5%和10%热失重温度分别提高至246和338℃,800℃残炭率达86.2%。适量MTES改性可有效抑制常压干燥过程中的收缩与开裂,构建均匀完整的三维介孔网络,显著提升气凝胶的结构稳定性、力学性能和隔热性能,所制备的SiO 2气凝胶复合材料在超低能耗建筑保温领域展现出良好的应用前景。 展开更多
关键词 SiO 2 气凝胶 疏水改性 热稳定性 力学性能
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Preparation and upconversion luminescence properties of LaF_3:Yb^(3 +),Er^(3 +) /SiO_2 nanocomposites with core /shell structure 认领 引用
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作者 曲玉秋 李美成 赵连城 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第3期73-76,共4页
LaF^3+ Yb^3+ , Er^3+ nanoparticles were successfully synthesized using solvothermal treatment, and LaF^3+ Yb^3+ , Er^3+/SiO2 core/shell nanoparticles were also prepared with reverse microemulsion technique. The ... LaF^3+ Yb^3+ , Er^3+ nanoparticles were successfully synthesized using solvothermal treatment, and LaF^3+ Yb^3+ , Er^3+/SiO2 core/shell nanoparticles were also prepared with reverse microemulsion technique. The crystal structure, morphology and photoluminescence properties of as-prepared core/shell nanoparticles were in- vestigated by X-ray diffraction, transmission electron microscopy and fluorescence spectrophotometer. The re- sults showed thatLaF^3+ Yb^3+ , Er^3+ nanoparticles are of hexagonal structure and SiO2 shell is amorphous. The size ofLaF^3+ Yb^3+ , Er^3+. nanoparticles is 13 nm and the LaF^3+ Yb^3+ , Er^3+/SiO2 nanoparticles present clearly a core/shell structure with 12 nm shell thickness. The solubility of LaF^3+ Yb^3+ , Er^3+ nanocrystals in water and the biocompatibility are both improved by the SiO2 shell. The upconversion luminescence spectra suggested that the SiO~ shell has small effect on the upconversion luminescence properties of the LaF^3+ Yb^3+ , Er^3+ nanocrys- tals. The core/shell structure LaF^3+ Yb^3+ , Er^3+ /SiO2. nanopartlcles are expected to be used in biological appli- cations. 展开更多
关键词 LaFz Yb3 , Er3 /SiO2 nanocomposites core/shell structure upconversion luminescence
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