为...的前驱

With oxalic acid and hexamethylenetetramine as the catalysts, and phenolic resin and tetraethoxysilane as the starting materials, a two-step sol-gel processing is developed for preparing Si〓N〓/SiC precursors with homogeneous microstructure composed of nanometer sized particles.

用草酸和六次甲基四胺为催化剂，酚醛树脂和正硅酸乙脂为原料，探索出了制备结构均匀而精细的Si〓N〓／SiC前驱体的溶胶—凝胶两步法。

Mesoporous molecular sieves, named SAN-01, were hydrothermally synthesized with microcline, a natural ore, as starting material, and the seeds of 13X zeolite as pore-wall＇s crystal source.

以微斜长石制备的硅铝酸盐前驱物为主要原料，以13X沸石晶核剂为孔壁结构导向剂，水热合成了含有13X沸石基本结构单元的硅铝酸盐介孔分子筛SAN-01。

During the process of peptization and hydrothermal crystallization, the aggregation behavior and the resulting morphology of nanocrystalline titania (TiO2) were studied by X-ray diffraction, scanning electron microscope, and dynamic light scattering techniques.

通过XRD、SEM和动态光散射粒度测定仪研究了胶溶及水热晶化过程中纳米TiO2晶粒聚集行为及形貌。实验结果表明，在胶溶无定形沉淀过程中所形成的大小为10-15nm的锐钛矿型胶粒或金红石型胶粒易定向聚集成更大的、具有(30-50)nm×(80-100)nm的次级晶粒。含有次级晶粒的溶胶前驱液在水热晶化过程中，次级晶粒发生崩裂并生长成结晶度更高的大小约为10-30nm球形和大小约为20-60nm棒状纳米TiO2

The porous SiO2 xerogels with controlled structure were obtained from TEOS in the presence of PEG by sol-gel method.

采用溶胶-凝胶法，以正硅酸乙酯为前驱体，以不同分子量的聚乙二醇为改性剂，制备结构可控的多孔SiO2干凝胶。

In this paper, SiO_2-based air-water interfacial films with nano structure are templated by cationic surfactant cetyl trimethyl ammonium bromide with tetraethyl orthosilicate as precursor.

本文以正硅酸乙酯为前驱体、以十六烷基三甲基溴化铵为模板，用自组装的方法在特殊的区位——空气—水界面上制备了SiO_2的无机纳米薄膜。

A novel type of caged bicyclic phosphorous functionalized silsesquioxane was synthesized from caged bicyclic phosphorous quadridentate silicon complex in the presence of tetramethylammonium hy- droxide. The product was confirmed by FTIR, 29Si MAS NMR, MS and XRD spectra.

以双环笼状含磷四配位硅为前驱体，四甲基氢氧化铵为催化剂反应得到具有高度对称结构的双环笼状磷酸酯取代倍半硅氧烷，通过红外光谱，29Si固体核磁共振谱，质谱和X衍射光谱等手段确定了产物的结构和晶型。

The results show that the zirconium sol has good spinnability when n: n= 1:3, reaction time is 6h and aging temperature is 15℃. The ZrO_2precursor fibers are made from hydrous zirconia chelated by acetylacetone. The sintercd fibers arecomposed of metastable tetragonal phase and sized about 15μm in diameter. Moreover, there aremany pores inside the fibers, but no cracks.4. ZrO_2/PVP hybrid fibers were prepared by blending the spinnable zirconium sol and 10 wt%PVP solution.

结果表明，当n(ZrOCl_2·8H_2O)：n(H_2O_2)=1：3，反应时间6h，陈化温度15℃时可得纺丝性能良好的锆溶胶，ZrO_2前驱体连续纤维的组成主要为经乙酰丙酮配位的ZrO_2水合物，热处理后的ZrO_2纤维的相结构为亚稳四方相，纤维的直径为15μm左右，纤维中存在大量的纳米级气孔，但无明显裂纹。4。

Ceramiccoated cemented carbide cutting tools are prepared from aluminum alkoxide solution and carbide substrates by solgel ro ute. The carbide substrates is coated with boehmite sol by dipcoating process and d ried to get gel film.

以异丙醇铝为前驱物，将溶胶-凝胶工艺应用于硬质合金刀片涂层，研制成功一种新型的陶瓷涂层刀片，从而为涂层刀具制造展示了一种全新的涂层方法。

Then the surface of the star polymer was intramolecularly crosslinked using octa(3-azidopropyl)polyhedral oligomeric silsesquioxane, POSS-(N_3)_8,as the inorganic multifunctional crosslinker at high dilution concentration via click chemistry,forming a novel POSS/polymer hybrid nanostructure.Thermogravimetric analysis shows that after surface crosslinking, the thermostability of the core crosslinked PS can be remarkably improved.In the second work,we synthesized of a novel polymer with quatrefoil-shaped topology.

接着，我们合成了一种结构规整的含八个叠氮功能团的无机分子—多面低聚倍半硅氧烷，以其为交联剂，我们通过Click反应在即稀浓度下实现了前驱体星型聚合物的分子内表面交联，得到了外层为无机分子交联，内层为有机高分子的星状高分子，这种新型的星状聚合物表现出了优良的热稳定性能。

The resultant powder was pressed into rods of 10 mm in diameter and 15 mm in length, and treated at 10 MPa and 900℃for 10h with a hot-pressing facility, then further sintered at 1300℃for 10h, at last the pressed rods were cut into pellets with 1mm in thick.

采用溶胶-凝胶方法制备一系列不同浓度的Fe~(3+)掺杂钛酸钡前驱粉体，再将粉体压制成直径为10mm，高度为15mm的圆柱体，采用热压炉在10MPa，900℃下热压10h后，并进一步在1300℃下烧结10h。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失