查询词典 rare earth

Finally, pentyl acetate and benteine could be respectively synthesized by esterification reaction in the presence of nanometer rare earth composite solid superacids (SO_4)~(2-)/ZrO_2-Gd_2O_3 and (SO_4)~(2-)/ZrO_2-Nd_2O_3. The effects of reaction time, reaction temperature, the mol ratio of acid to alcohol and the use level of catalyst on esterification yield were discussed. In the end, we obtained their optimal reaction conditions.

采用纳米稀土复合固体超强酸SO_4~(2-)/ZrO_2-Gd_2O_3，SO_4~(2-)，~/ZrO_2-Nd_2O_3分别合成了乙酸戊酯和乙酸苄酯两种香料，实验考察了反应时间、反应温度、醇酸比及催化剂的用量对酯化率的影响，并由此得出反应的最佳条件。

Rare-earth element lies in sixth period among periodic table of chemical element and includes the 15 elements of lanthanides and elements scandium and yttrium.

稀土元素在化学元索周期表中，为第六周期，属于镧系族及钪、钇共17种元索的总称。

Studies on mineralogy, isotope and trace elemental geochemistry of the pegmatite will make it possible to reveal the principals of petrogenesis and evolution of pegmatite, and the geochemical behaviors of rare-earth elements and other trace elements in magmatic-hydrothermal transition stage.

由于LCT型伟晶岩具有明显的分带性、矿物颗粒大小不均匀性等特点，因此利用全岩样品研究伟晶岩往往因取样没有代表性而被大多数岩石学家和地球化学家所否定。

By means of maceration-wave, added rare earth and CTMA to the bentonite, which produced a new absorbent. The adsorbent behaviour of adsorbent on phosphonium was discussed.

通过浸渍微波辐射法制备镧和CTMA改性的稀土吸附剂，探讨了吸附剂对磷的吸附性能。

Then, the technique is applied to study the coherent dynamics by detecting the photoconductivity for bulk GaAs, and fluorescence for rare earth solids.

然后，我们在研究了半导体材料和稀土样品的稳态性质后，用上述方法测量了GaAs体材料的光电导信号和稀土材料的荧光信号，研究其激发态的相干态动力学过程。

Chapter Five: We use photoemission spectroscopy to study the interaction of the rare earth metal Cerium overlayers with GaSb (111) surface and their oxidation behavior as well.

第五章 利用超高真空中的光电子能谱的测量，就稀土金属Ce对半导体GaSb(111)表面的催化氧化特性进行了研究，并且研究了Ce的厚膜本身的氧化，探讨了Ce在催化氧化中所起的作用。

Rare earth has been widely used in metallurgy and material fields for its special physical chemistry properties.

稀土以其特殊的物理化学性质在冶金及材料领域有着广泛的应用。

The findings of this study will be helpful to understand the mechanism of physiological effects of rare earth elements.

本研究的结果将有助于解释稀土植物生理效应的机制。

The stability of the rare earth picrate complexes with open-chain macrocyclic compounds was described quantitatively.

并对不同结构的开链大环化合物与稀土苦味酸盐配合物的稳定性进行了定量的描述。

Two ligands L~Ⅵand L~Ⅶhave been designedand synthesized containing different terminal groups and using benzo-12-crown-4 as theskeleton, and their 18 rare earth nitrate and picrate complexes also have been synthesizedand characterized.

第二章：以五种不同种类水杨酰胺为功能末端基设计合成出以苯并-15-冠-5为骨架的配体L~Ⅰ～L~Ⅴ，并合成了其稀土硝酸盐和苦味酸盐的10个系列共51个稀土配合物。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。