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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。

Results of research showed that it is easy to mix spherical powders with mercury by trituration and the amalgams of spherical powders are easier to fill, carve and polish than commercial amalgams made of cutting filing powders.

球粉汞齐的性能，诸如固化过程中的尺寸变化，压缩强度，流变及蠕变等均达到美国牙医协会技术指标。

Aiming at the unmelted powders splash from collision between electron and powders, optimized process parameters is selected to pre-heat the powders to obviously reduce the splash.

针对实验中出现的电子与粉末碰撞造成的未熔粉末的飞溅，采用优化的工艺参数对粉层进行预热，从而大大减少了未熔粉末的飞溅。

As the density of Al and Cu was quite difference,it was apt to delaminate and restrain the process of alloy by wet milling.The case was improved when dry milling,though it would be some reunite with the time of ball-milling prolonging.(2)The best technique parameters of high energy ball milling to prepare metastable powders of Cu-Al alloy were;the addition of Al powders was 1% in quality,the powders of Cu-Al were completely alloyed after high energy ball milling for 20 h.

1提出采用高能球磨制备Cu-Al合金粉的有效方法，认为由于Cu和Al的密度相差比较大，采用以液态酒精为过程控制剂的湿磨时，容易发生分层，抑制了合金化，采用干磨时，以硬脂酸为过程控制剂，虽然随球磨时间的延长会发生轻微的团聚，但能达到良好的合金化效果。

The results show that, by the way of optimizing preparation condition, the spherical zirconia powders with suitable particle size distribution are prepared using chemical precipitation method. Using heterogeneous chemical precipitation coating technique, the sph, erical nickel coated zirconia powders are prepared and the heterogeneous nucleation can be done on the surface of spherical zirconia powders. The thickness of coated layer, homogeneous degree and crack of surface can be controlled by the way of controlling powder concentration, adding rate of reactants feeding and adding surface active agent.

研究表明，采用化学沉淀法，通过优化制备工艺条件，可以制备粒径分布较均匀的球形氧化锆粉体；利用非均相化学沉淀包裹技术制备的金属镍包裹氧化锆微球粉体，球形氧化锆颗粒表面作为异相成核的场所，通过控制颗粒浓度、加料速度以及添加表面活性剂等工艺条件，可以调控包裹层厚度、表面均匀度以及表面裂纹等。

The particle size distribution fractal was introduced into powders' flowability testing, through used the mathematical model which utilize the geometry properties of the particle, and propitious to the digital micrographic image analysis method. It was gained the fractal dimensions, discussed the relationship between the powders' flowability denotation parameters and powders' PSDF, and also made a primary research about the action effect of flow addition reagent magnesium stearate.

本文中在颗粒流动性测试时引入粒度分布分形维数，通过采用利用颗粒几何特征，便于采用数字显微和用像处理计算粉体粒度分布分形维数值的数学模型，得到粉体粒度分布分形维数值，探讨颗粒流动性表征参数与粉体粗度分布分形维数值间的关系；并就流动助剂硬脂酸镁对粉体流动性能的改进与粉体粒度分布分形维数值关系进行了初步探讨。

He TiC could reprecipitate again with excess milling and Cu crystal decreasing. TiC-dispersion-strengthened Cu-based composite powders have been prepared from TiC-Cu and Cu-Ti-C mixed powders by MA. The composite powders were prepared into composite materials by pressing, sintering and heat-extrusion.

IC混合粉末经机械球磨后，再经压制、烧结和热挤压制备成 n 弥散强化铜基复合材料。

The cause of hard agglomerate formation and its effect on sinterability were investigated. The water-washed ZrO〓-Y〓O〓 powders were found to be greatly made up of hard agglomerates. The ethanolwashed powders also contained a few of hard agglomerates because of uneffective dehydration. Beside, ethanol volatilizes in advance of water during drying because ethanol has a lower boiling point than water, so steric effects of ethanol won't act. However, nearly no hard agglomerate formed in the azeotropic distilled powders, because of effective dehydration and higher boiling point for n-butanol.

研究指出，水洗工艺所得ZrO〓-Y〓O〓粉末几乎完全由硬团聚组成；乙醇洗涤工艺的脱水效果不是很好，并且由于乙醇的沸点比水低，以致在干燥过程中残留乙醇比水先挥发，乙醇的空间位阻效应不能有效地发挥作用，因此，仍然可以导致产生一定量的硬团聚；而共沸蒸馏工艺的脱水效果最佳，且正丁醇的沸点比水高，干燥时残留正丁醇比水后挥发，从而正丁醇的空间位阻效应可有效地发挥作用，因此避免了在煅烧过程中形成Zr-O-Zr键，即共沸蒸馏粉末中不含硬团聚。

The present invention is characterized in that the ammonium metatungstate powders and the cobltic-nitrate powders are respectively dissolved in the water and scattered in the liquid nitrogen to be pre-frozen using a nitrogen spray gun after being mixed and defecated, and then are placed in a freezedryer to be dried vacuumly and finally the powders are obtained. The nanometer powder i.e. the nano tungsten-cobalt composite powder is obtained by reducing the freeze-dried mixed powder in the atmosphere of hydrogen.

该微晶硬质合金的制备方法特征为：将偏钨酸铵粉末与硝酸高钴粉末分别溶于水中，混合澄清后使用氮气喷枪，将其分散在液氮中预冻后置于冻干机中进行真空干燥得到粉末；在氢气气氛中对冻干的混合粉末进行还原得到纳米粉体，即钨钴纳米复合粉体。

Comparing the alignment degree of sintered magnets and the green compacts from three kinds of powders, it is found that HD powders have the worst alignment degree in the same field, while the 350℃ degassed powders have the best alignment degree.

一般而言，实际生产中，采用HD工艺进行粗破碎的NdFeB磁粉应当经过300℃左右温度脱氢，使主相完全脱氢，以减少磁粉吸潮氧化的机会，同时可以获得更好的取向度。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。