稀土

First, the dissertation summarizes the properties, developing state and application fields of BLDCM, then its fundmental structure; operation principle and control strategy is also presented. On the base of roundly analyzing all kinds of the drive motor in electromotion type railway switch, BLDCM is proposed to replace the formerly traditional DC motor in railway switch. Second, the whole design scheme and key technology of control system is put forward based on analyse of the technical parameters and requirements.

首先，论文介绍了无刷直流电动机的特点、发展和应用概况，分析了稀土永磁无刷直流电机系统的基本构成、工作原理和控制方法；在对目前各种电动转辙机驱动电机分析的基础上，提出将稀土永磁无刷直流电机用于铁路转辙机，以替换原有的串励有刷直流电动机。

The applications of the rare earth electrothermal paint on the cement surface in winter are described.

报道了最新研制的稀土电热涂料的性能特点，并给出了稀土电热涂料在冬季施工中的应用实例。

The results showed that inclusions were spherical or ellipsoidal, and the cracks initiated firstly in the inner of inclusion.

结果表明：稀土夹杂物呈球状或椭球状，拉伸过程中稀土夹杂物内部最先萌生裂纹。

1"Euxenite:a lustrous, blackish-brown rare -earth mineral consisting primarily of cerium, erbium, titanium, uranium, and yttrium."

黑稀金矿：一种光亮的棕黑色稀土矿石，主要由铈、铒、钛、铀和钇构成。〞钇被用作稀土金属一种理想的非磁性稀释剂。

Ground state absorption, excitation state absorption and energy transfer were used in discusing the up-conversion mechanism of the glasses were proposed.

讨论稀土离子的基态吸收、激发态吸收以及稀土离子之间能量传递的关系，建立了相关的上转换机制模型。

Prices have risen about fivefold since 2000, but the financial and economic crisis has put pressure on the price of some of them.

自2000年以来，稀土价格上涨了大约5倍，但经济及金融危机对某些稀土的价格构成了压力。

The orthogonal design method is used for preparation of rare earth fluoride by rare earth oxide(Gd_2O_3) fluorination with NH_4HF_2 in this paper.

采用正交试验法，研究了用氟化氢铵作氟化剂直接与稀土氧化物(Gd2O3)反应，制备稀土氟化物的工艺，确定了氟化的最佳工艺条件，并进行了分析讨论。

The main reason for these was ascribed to the replacement effect of rare earth elements to heavy metal.

实验发现重金属的形态和积累的确受到外加稀土的影响，引起变化的原因主要归结为外加稀土元素发生的替代反应，这种替代作用表明施加稀土肥干扰了土壤中的金属平衡，值得进一步的研究。

In this paper, with 2-oxo-propionic acid salicyloyl hydrazone as a ligand, one calcium complex, three copper complexes and thirteen rare earth(RE=La, Ce, Pr, Nd, Sm, Eu. Gd, Tb, Dy, Er, Tin, Yb and Lu) complexes have been synthesized. The crystals of four complexes were obtained, and the crystal structures were determined by single crystal X ray diffraction. One of the crystals is calcium complex, the other are binary and trinary complexes of copper.

本文选用2-羰基丙酸水杨酰腙作为配体，在水中分别与钙、铜、稀土(RE=La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Er、Tm、Yb和Lu)的盐反应，共制得了17种未见文献报道的配合物，另外还培养了2-羰基丙酸水杨酰腙、咪唑与铜、钙的二元及三元配合物的四种单晶，对La-Gd的稀土的配合物进行了溶解热的测定，并用Gauss-98软件包对铜的配合物进行了有关量化计算。

Mainly engaged in rare earth hydrometallurgy, Pyrometallurgical metallurgy, as well as Rare Earth Functional Materials research and preparation.

主要从事稀土湿法冶金、火法冶金以及稀土功能材料的研究和制备。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。