silica

摘要： A flexible anode composite,carbon cloth@SiO_(2)composite(CC@SiO_(2)),was synthesized by a one-step solution method using tetraethyl orthosilicate(TEOS)as the silica source.CC@SiO_(2)can be directly used as the negative electrode material for lithium-ion battery,and its initial reversible deintercalation capacity reaches 1358.7 mA·h·g^(-1).The electrode shows a capacity of 863.8 mA·h·g^(-1)up to 130 cycles at 0.5 A·g^(-1),displaying excellent rate performance and cycle stability.

摘要： Fused silica and KBr samples were irradiated with a 2.7 MeV electron beam.The emission of fused silica and KBr samples in the UV and visible regions was studied under various experimental conditions.Numerical simulation of optical emission was carried out using the GEANT4 computer platform.Simulations of energy spectra and angular distributions of the beam electrons were performed for different target thicknesses.The results reveal the effect of scattering of the beam electrons on the angular distribution of Cherenkov radiation in fused silica samples with thicknesses exceeding the electron path length.

摘要： Ceramic cores are widely used in investment casting,and ideal properties of cores are essential for high-quality castings.Under the circumstances requiring thick cores,solid cores are likely to encounter deformation and cracking defects due to the accumulation of shrinkage.Therefore,with the superiority of ceramic stereolithography in producing complex ceramic parts,hollow cores with lattice structures were designed and fabricated.The dimensional accuracy and properties of the green and sintered bodies were evaluated.Results show the dimensional accuracy of sintered cores is controlled within±0.25 mm benefited from the precise green bodies.The mechanical properties are not obviously deteriorated.The bending strength reaches 11.94 MPa at room temperature and 12.87 MPa at 1,500°C with a creep deformation of 0.345 mm.Furthermore,casting verifications prove that the hollow cores meet the requirements of investment casting.Smooth casting surfaces are obtained,at the same time,the core-removal efficiency is improved by over 3 times.

摘要： The properties of coatings formed on the MA8 magnesium alloy by the plasma electrolytic oxidation in electrolytes containing mechanical mixture of zirconia and silica nanoparticles in concentrations of 2,4 and 6 g/l have been investigated.It has been established by SEM,EDS,and XPS that ZrO_(2)/SiO_(2)nanoparticles successfully were incorporated into the coatings.Micro-Raman spectroscopy showed the presence of ZrO_(2)in tetragonal and monoclinic forms in the PEO-coating composition as well as Mg2SiO4 in tetrahedral configuration uniformly distributed in the outer part of coatings.Obtained coatings significantly reduce corrosion current density in comparison with bare Mg alloy and base PEOlayer(from 2.4×10^(–7)A/cm^(2)for base PEO layer to 0.7×10^(–7)A/cm^(2)for coatings with nanoparticles).It has been found that the presence of solid nanoparticles in the composition of coating has a positive effect on their hardness(this parameter was increased from 2.1±0.3 GPa to 3.1±0.4 GPa)and wearproof(the wear was reduced from(4.3±0.4)×10^(–5)mm^(3)/(N×m)to(3.5±0.2)×10^(–5)mm^(3)/(N×m)).

摘要： Water has remarkable effects on the properties of mantle rocks,but,owing to the high temperatures in the mantle,uncertainties remain about how and how much water is transported into the deep Earth.Recent studies have shown that stishovite and post-stishovites as highpressure phases of SiO2 have the potential to carry weight percent levels of water into the Earth’s interior along the geotherm of the subducting oceanic crust.As slabs are subducted to the deepest mantle,dehydration of these dense hydrous silica phases has the potential to change the physicochemical properties of the mantle by reducing melting points,forming new high-pressure phases,and enhancing the oxygen fugacity heterogeneity of the lower mantle.

摘要： High-temperature proton-exchange membrane fuel cells(HT-PEMFCs)have shown a broad prospect of applications due to the enhanced reaction kinetics and simplified supporting system.However,the proton conductor,phosphoric acid,tends to poison the active sites of Pt,resulting in high Pt consumption.Herein,Pt nanoparticles anchored on SiO_(2)-modified carbon nanotubes(CNT@SiO_(2)-Pt)are prepared as high-performance cathode catalysts for HT-PEMFCs.The SiO_(2)in CNT@SiO_(2)-Pt can induce the adsorption of phosphoric acid transferring from Pt active sites in the catalytic layer,avoiding the poisoning of the Pt,and the phosphate fixed by SiO_(2)provide a high-speed proton conduction highway for oxygen reduction reactions.Accordingly,The CNT@SiO_(2)-Pt cathode achieve superior power density of 765 mW cm^(−2)(160°C)and 1,061 mW cm^(−2)(220°C)due to the rapid proton-coupled electron process and outstanding stability in HT-PEMFCs.This result provides a new road to resolve the phosphate poisoning for the commercialization of HT-PEMFCs.

摘要： The past 20 years have witnessed the rapid growth of photonic integration circuits(PIC)technology,which has been warmly embraced by both academia and the industry.Powered by the advanced development in material growth,processing,and design capability,the PIC technology now covers multiple material platforms,including III–V(InP,GaAs),silicon,silica,lithium niobate on insulator(LNOI)polymer,etc.The integration level has evolved from a single functional device to thousands of components on-chip.The increase in the performance and the complexity of the PICs have become an energetic booster for communication and information technology.

摘要： Irradiation with swift heavy ions causes the deformation of Ferric nanoparticles in direction of the ion beam.Fe nanoparticles with mean diameter of about 20 nm were prepared by gas flow sputtering and subsequently confined within silica films.Two silica films wherein two different densities of Fe nanoparticles are encapsulated were irradiated with 50 MeV Ag ions with fluences of few 1014 ions.cm^(-2) at 300 K and normal incidence.Transmission electron microscopy analysis shows that the spherical Fe nanoparticles are deformed into prolate nanorods aligned in direction of the incident ion beam.The depth distribution profiles of irradiated particles reveal the presence of a critical fluence above which the elongation kinetics becomes dependent on the nanoparticles density.Analysis indicates that for the lower density particles,a saturation length is reached under irradiation to fluence between 3-4×10^(14) ions.cm^(-2).However,for the higher density,collective growth into aligned nanowires is presumed to take place.Hysteresis curves of the saturation magnetization and coercivity indicate an increasing magnetic anisotropy,which can be correlated with the deformation of nanoparticles in the direction of the ion beam.

摘要： 本发明公开了一种利用超临界CO2和Nano‑Silica提高煤层气采收率的方法，主要包括：Ⅰ、煤样的采集与制备：选取目标煤层的煤样进行粉碎；Ⅱ、添加溶蚀剂Nano‑Silica：将实验煤样与粒径为15±5nm级的SiO2混合均匀，并放入反应釜内；Ⅲ、控制反应釜内的气体环境，进行超临界CO2处理；Ⅳ、对煤样的孔隙结构特征以及有机物分子结构进行分析。本发明利用超临界CO2对煤样进行浸泡，改变了煤体的结构，并通过在煤样中添加溶蚀剂Nano‑Silica，进一步提高了煤体孔裂隙的发育程度，不仅有利于煤体渗透率的提高，而且有利于煤层气的增产。

摘要： 本发明涉及一种二氧化钛微球@全硅Silica‑1分子筛核壳催化剂、制备方法及用途。所述催化剂核相为二氧化钛微球，壳层为全硅Silica‑1分子筛，可用于碳酸二甲酯与乙酸苯酯酯交换反应制备碳酸二苯酯的工业生产中。

摘要： 本发明涉及一种基于Silica/chitosan/Ru纳米粒子电化学发光法检测汞离子的方法，其是由步骤(1)合成掺杂壳聚糖和联吡啶钌的二氧化硅复合纳米粒子、(2)空白Silica/chitosan/Ru‑ssDNA体系的制备、(3)Silica/chitosan/Ru‑DNA/Hg体系的制备、(4)修饰电极的组装、(5)电化学发光信号检测、(6)ΔIi‑CHgi标准曲线以及(7)检测组成，其无需复杂的探针分子标记和固定过程，省时、成本低并且不影响富含T碱基的DNA对汞离子的识别，同时将化学修饰电极、纳米粒子富集技术和电化学发光分析技术结合起来，实现了高灵敏度检测Hg2+，检出限达3pM。

摘要： 本发明公开了一种利用超临界CO2和Nano‑Silica提高煤层气采收率的方法，主要包括：Ⅰ、煤样的采集与制备：选取目标煤层的煤样进行粉碎；Ⅱ、添加溶蚀剂Nano‑Silica：将实验煤样与粒径为15±5nm级的SiO2混合均匀，并放入反应釜内；Ⅲ、控制反应釜内的气体环境，进行超临界CO2处理；Ⅳ、对煤样的孔隙结构特征以及有机物分子结构进行分析。本发明利用超临界CO2对煤样进行浸泡，改变了煤体的结构，并通过在煤样中添加溶蚀剂Nano‑Silica，进一步提高了煤体孔裂隙的发育程度，不仅有利于煤体渗透率的提高，而且有利于煤层气的增产。

摘要： 本发明涉及一种二氧化钛微球@全硅Silica-1分子筛核壳催化剂、制备方法及用途。所述催化剂核相为二氧化钛微球，壳层为全硅Silica-1分子筛，可用于碳酸二甲酯与乙酸苯酯酯交换反应制备碳酸二苯酯的工业生产中。

摘要： 本发明涉及一种基于Silica/chitosan/Ru纳米粒子电化学发光法检测汞离子的方法，其是由步骤(1)合成掺杂壳聚糖和联吡啶钌的二氧化硅复合纳米粒子、(2)空白Silica/chitosan/Ru-ssDNA体系的制备、(3)Silica/chitosan/Ru-DNA/Hg体系的制备、(4)修饰电极的组装、(5)电化学发光信号检测、(6)ΔIi-CHgi标准曲线以及(7)检测组成，其无需复杂的探针分子标记和固定过程，省时、成本低并且不影响富含T碱基的DNA对汞离子的识别，同时将化学修饰电极、纳米粒子富集技术和电化学发光分析技术结合起来，实现了高灵敏度检测Hg2+，检出限达3pM。

摘要： 本发明涉及一类两亲性配体可以稳定疏水性分子晶体于水相中且可以润湿晶体与silica之间的界面能使得晶体可以被silica包覆的技术，该技术可以实现超高的药物负载效率且可应用疏水药物的递送及可控释放。(1)在常温下，配制低浓度的两亲性配体的水溶液。(2)将适量待包覆的疏水性分子的溶液在涡流的条件下迅速加入到步骤(1)溶液中混合。(3)将步骤(2)所得产物分散在溶有硅源的醇与水的混合溶液中，然后加入适量催化剂，最后在搅拌的条件下反应数个小时可以得到晶体@silica产物。本发明所需原料简单易得，操作过程简便、安全，成本低，产率高，负载效率高，可以适于工业规模化生产，具有较强的实用性。

摘要： 本发明公开了一种超薄silica纳米片及其制备方法，属于二氧化硅纳米片制备技术领域。其技术方案为：将十六烷基三甲基溴化铵和二甲基双十四烷基溴化铵两种模板剂溶于水中，并加入碱性溶液和乙醇，充分搅拌后加入硅氧烷和油溶性溶剂，形成油‑水两相反应体系，搅拌后，即在水相中得到中间厚度低于5nm的silica纳米片。采用本发明的方法，能够制备出尺寸均一且中间厚度低于5nm的单分散片状silica纳米材料。

摘要： 本发明涉及一类两亲性配体可以稳定疏水性分子晶体于水相中且可以润湿晶体与silica之间的界面能使得晶体可以被silica包覆的技术，该技术可以实现超高的药物负载效率且可应用疏水药物的递送及可控释放。(1)在常温下，配制低浓度的两亲性配体的水溶液。(2)将适量待包覆的疏水性分子的溶液在涡流的条件下迅速加入到步骤(1)溶液中混合。(3)将步骤(2)所得产物分散在溶有硅源的醇与水的混合溶液中，然后加入适量催化剂，最后在搅拌的条件下反应数个小时可以得到晶体@silica产物。本发明所需原料简单易得，操作过程简便、安全，成本低，产率高，负载效率高，可以适于工业规模化生产，具有较强的实用性。

摘要： 本发明公开了一种原位合成的NR/silica纳米复合材料，所述的NR/silica纳米复合材料的原料组分和含量如下：天然橡胶胶乳(NR latex)100g，硬脂酸1～2g，石蜡1～1.5g，炭黑15～30g，氧化锌2～5g，硫磺1～1.5g，防老剂40201～2g、促进剂TBBS 0.5～2g。本发明采用原位合成NR/silica纳米复合材料，制备方法简单、方便操作；通过对硫化曲线分析可知，原位合成NR/silica纳米复合材料比普通的制备方法得到的NR/silica纳米复合材料具有更好的硫化性能；通过对原位合成NR/silica纳米复合材料使用透射电镜进行表征，由结果可知，白炭黑作为分散相，分散的较均匀，适于大规模工业化生产。