查询词典 titanium

Titanium dioxide has been extensively used as photocatalyst in nowadays. But aggregation between nanoparticles results in a lower photoactivity.

目前奈米二氧化钛光触媒应用已相当广泛，但奈米粉体之间因为容易发生团聚的现象，而降低奈米二氧化钛的效能。

Due to its large surface area, mesoporous structure, pure anatase structure and high adsorption capacity, the photoactivity of 31%TiO〓/SiO〓 was much higher than that of the pure titanium dioxide.

多孔硅胶抑制了高温时TiO〓晶型由锐钛矿向金红石型的转变，并且对TiO〓具有很好的分散能力。

It was found that photochemical deposition of Hg occurred at the layer of TiO2 covering the surface of titanium electrode under UV irradiation, the adsorption of sulfadiazine on the photochemically deposited Hg was stronger than that on the electrochemically deposited Hg, and a method for the determination of sulfadiazine was proposed by the adsorptive stripping voltammetry based on photo-chemical deposition of Hg on Ti electrode.

该研究发现采用紫外光照射钛电极表面氧化钛层能够光催化还原Hg(上标致2+)生成Hg微粒，在Ti基电极上光化学沉积Hg比电化学沉积Hg对磺胺嘧啶具有更强的吸附作用，基于光化学沉积Hg/Ti电极建立了一种吸附溶出伏安法测定磺胺嘧啶的方法。

Progress in pinacol coupling of aldehydes and ketones using low valent titanium is reviewed in recent years.

由低价钛络合物诱发的片呐醇偶联反应，具有良好的化学选择性和立体选择性，近几年来又引起有机化学家们的极大兴趣与重视。

Methods for synthesizing of pinacol are reviewed,the difference of catalytic effects and stereoselectivity with various catalytic systems are introduced in this paper.Highlights are laid on the mechanism and stereoselectivity of new synthetic methods catalyzed by low valent Samarium, Titanium and Trimethyl chlorosilane, etc.

频哪醇合成新进展* The Recent Progress in the Synthesis of Pinacol 李有桂蒋昌盛尤田耙**(中国科学技术大学化学系合肥 230026)本文综述了合成频哪醇的方法，介绍了不同催化体系的催化效果和立体选择性的差异，着重介绍了低价钐、低价钛、三甲基氯硅烷等新的合成频哪醇反应的机理和立体选择性。

METHODS: Titanium nails (1.5 mm in diameter) were separately inserted on two sides of left premaxillary suture in rabbits. A self-made distraction device was used. Gelatum-like substance [V(subscript platelet-rich plasma):V=9:1] was injected into the left premaxillary suture of experimental group rabbits immediately prior to distraction.

分别在家兔左侧前颌缝的两侧置入钛钉（直径1.5mm），戴自制前牵引装置，试验组在牵张开始时，注射V∶V=9：1混合的凝胶样物质至左侧前颌缝内。

This thesis mainly focuses on overcoming the substrates limition of the present catalytic systems,low catalytic efficiency,and application in total synthesis.1.Conveniently synthesized sulfonamide alcohol titanium complex has been used to catalyze the asymmetric addtition of methyl propiolate to various aromatic and aliphatic aldehydes with high enantioselectivity.

本论文即针对现有催化体系的底物局限性、催化效率低、应用研究少等展开研究：1、我们将简便合成的磺酰胺基醇配体-钛催化体系应用于催化丙炔酸甲酯对各类芳香醛及脂肪醛的不对称加成取得了理想的结果。

Methods Since 1993,314 cases of 364 cone-screw-typed and bl ade-typed implants used CDIC pured Titanium were analysed.

总结自93年以来用CDIC钝钛锥状螺旋和叶状种植体修复的314例364枚种植体。

The traditional solid phase reaction of preparation has many disadvantages: it is very difficult to get the pure calcium-titanium mine phase even at the annealing temperature of 1000DEG C; the size of the material is very large and ununiform; the powder needs very high agglutinating temperature (1350DEG C) to get pyknotic ceramics.

固相反应法制备铌钪酸铅，在1000℃的较高的煅烧温度下也难于得到纯钙钛矿相的粉体，且颗粒尺寸大，尺寸分布不均匀，且这种粉体而要求高的烧结温度(1350℃)以获得致密的陶瓷。

Regular coiled carbon tubes are prepared by pyrolytic decomposition of acetylene on titanium plates at 750℃.

规则螺旋碳管的形成与钛片的预处理有关，在盐酸处理过的钛片表面上所生长的碳管几乎都是规则螺旋形状的。

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。