三氧化钛

The titanium dioxide is one kind of important industrial chemicals, mainly has the brookite, Rutile and anatase three crystal seeds.

二氧化钛是一种重要的化工原料，主要有板钛矿、金红石和锐钛矿三种晶型。

In the presence of the combination of sulphuric and phosphoric acid, with sodium diphenylamine sulfonate as the indicator, standard solution of potassium dichromate was used to titrate total iron value.

试样以盐酸溶解后，在酸性介质中，先以氯化亚锡将三价铁大部分还原为二价，然后在钨酸钠指示下，再以三氯化钛将剩余的三价铁还原为二价，过量的三氯化钛以重铬酸钾氧化消除干扰，在硫磷混合酸存在下，以二苯胺磺酸钠为指示剂，用重铬酸钾标准溶液滴定全铁量。

Secondly, opaline photonic balls which are narrow dispersed in size and in the range of a few or tens micrometers in diameter, were fabricated using monodisperse polystyrene latex particles.

第三，利用聚合物乳胶粒子形成的蛋白石结构的胶体晶体和光子球作模板，通过渗入二氧化钛前驱体，成功制备出以二氧化钛为骨架的，有序大孔反蛋白石结构的光子晶体和光子球。

"Its compounds, in which it has valence 2, 3, or 4, include titanium trichloride (used as a catalyst in polypropylene production), titanium dioxide (extensively used as a pigment -with the greatest hiding power of all white pigment s-in paints, enamels, and lacquers), and titanium tetrachloride (used in skywriting, smoke screens, and as a catalyst)."

钛的化合物(其中钛的原子价为2、3或4)包括三氯化钛(在聚丙烯生产中作催化剂)、二氧化钛(在油漆、釉药和漆器中广泛用作颜料，在所有白色颜料中掩盖能力最强)以及四氯化钛(用于空中显示图形文字、烟幕以及催化剂)。

"Its compounds, in which it has valence 2, 3, or 4, include titanium trichloride (used as a catalyst in polypropylene production), titanium dioxide (extensively used as a pigment-with the greatest hiding power of all white pigments-in paints, enamel s, and lacquers), and titanium tetrachloride (used in skywriting, smoke screens, and as a catalyst)."

钛的化合物(其中钛的原子价为2、3或4)包括三氯化钛(在聚丙烯生产中作催化剂)、二氧化钛(在油漆、釉药和漆器中广泛用作颜料，在所有白色颜料中掩盖能力最强)以及四氯化钛(用于空中显示图形文字、烟幕以及催化剂)。

"Its compounds, in which it has valence 2, 3, or 4, include titanium trichloride (used as a catalyst in polypropylene production), titanium dioxide (extensively used as a pigment-with the greatest hiding power of all white pigments-in paints, enamels, and lacquers), and titanium tetrachloride (used in skywriting, smoke screens, and as a catalyst )."

钛的化合物(其中钛的原子价为2、3或4)包括三氯化钛(在聚丙烯生产中作催化剂)、二氧化钛(在油漆、釉药和漆器中广泛用作颜料，在所有白色颜料中掩盖能力最强)以及四氯化钛(用于空中显示图形文字、烟幕以及催化剂)。

In chapter three, various theories and experience on the dispersion of nano-powders proposed by former researchers were generalized and reviewed. Technical standards and experimental process for determining technological parameters were suggested for the dispersion of nano-scaled metal oxides in aqueous medium according to their surface wettability, surface charge, the dependence of surface charge on pH and the compatibility of surfactants with pH and pH adjusting agents. Based on these suggested standards and experimental method, highly stable and dispersive aqueous suspensoid of nm-ZnO, nm-TiO〓, nm-Co〓O〓 and nm-MnO powders were prepared successfully and surface modification on these nano-powders was also achieved.

本文第三章通过大量的文献调研，归纳总结了前人在纳米粒子分散技术方面的理论和经验，并在此基础上根据纳米氧化物粉体的表面润湿性、表面电性及其与分散介质pH值的关系、表面活性剂及其与pH调节剂的配伍关系设计了纳米氧化物水分散体系的工艺规范以及确定工艺参数的通用实验步骤，成功地制备了纳米氧化锌、纳米二氧化钛、纳米氧化钴和纳米氧化锰的高稳定分散悬浮液并实现了干粉体的表面改性，为纳米材料在氧化锌压敏电阻中的应用创造了第二个前提条件。

In this thesis, three major achievements were made in theoretical study: conditions and rules for preparing nano-powders by chemical precipitation are analyzed from the point of view of thermodynamics and kinetics, the principle, standards and experimental method for the aqueous dispersion of nano-scaled metal oxide powders were proposed and verified, mathematical model of nano-filming addition of dopants by chemical coprecipitation was established. In experimental research, nm-ZnO, nm-Bi〓O〓, nm-Co〓O〓 and nm-MnO powder with spherical shape, narrow particle size distribution and small particle size were prepared successfully, highly stable and dispersive aqueous suspensoid of nm-ZnO, nm-TiO〓, nm-Co〓O〓 and nm-MnO powder were prepared successfully and surface modification on these nano-powders was also achieved, 0-3 nanocomposite ZnO varistors with nm-ZnO, nm-TiO〓and nm-MnO respectively were prepared successfully by conventional mechanical attrition, and exhibited much better electrical properties than those of conventional varistors.

综上所述，本文在理论研究方面取得了三项成果：（1）从热力学和动力学角度推导并分析了液相化学沉淀法制备纳米粉体的反应条件和规律，（2）提出了纳米氧化物的水分散体系的设计原理、规范和通用实验步骤，（3）提出了共沉淀的数学模型和计算方法；在实验方面所取得的成果有：（1）成功制备了粒度小、分布窄、形貌对称的纳米氧化锌、纳米氧化铋、纳米氧化钴和纳米氧化亚锰，（2）成功地制备了纳米氧化锌、纳米二氧化钛、纳米氧化钴和纳米氧化锰的高稳定分散悬浮液并实现了干粉体的表面改性，（3）成功地进行了纳米氧化锌、纳米二氧化钛和纳米氧化锰对压敏电阻的0—3复合掺杂实验，试样性能远优于常规压敏电阻，为实现压敏电阻的高能高压化提供了新的方法和思路。

In this paper,we compared the photodegradation efficiency of nano-titania films by using dichloroacetic acid,rhodamine B and methyl orange as the photocatalytic referents and the ultraviolet lamp as the source light to generate the photocatalytic reaction.

针对纳米氧化钛光催化性能研究中缺乏统一有效表征标准的现状，比较了二氯乙酸、罗丹明B和甲基橙三种光催化活性评价物的热稳定性和对紫外光的稳定性，并以氧化钛纳米薄膜为光催化剂，研究了三种评价物的光催化降解效率表征，以及酸碱度、通氧条件等因素对评价物在光催化活性表征中的影响及其机理，归纳了三种评价物对于纳米氧化钛光催化活性表征的优缺点。

When using urea-hydroperoxide as oxygent, just the trimethylphosphine adsorbed on the Lewis acid sites in TS-1 zeolite was oxidized. It further confirmed that the hydroperoxo-titanium species formed by the interaction between the titanium in Lewis acid sites and urea-hydroperoxide are the active oxidation center, and the titanium in the framework as Lewis acid sites enhances the oxidation ability of hydroperoxide. 3. Phenylacetaldehyde and benzaldehyde are found to be the major products in the catalytic oxidation of styrene over TS-1 zeolite, and styrene epoxide is not as speculated detected.

当以过氧化氢尿素为氧化剂时，室温条件下吸附在TS-1分子筛Lewis酸性位的三甲基膦即能被氧化，由此进一步证明，TS-1分子筛中由Lewis酸性位的骨架钛与过氧化氢相互作用形成的过氧化钛物种是三甲基膦氧化反应的活性中心，骨架钛作为Lewis酸中心提高了过氧化氢的氧化能力。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。