前驱

The effects of the spray-drying process of the ammonium paratungstate and the carburization temperature on the formation of the precusor and WC powder were investigated.

采用喷雾干燥-固定床法制备碳化钨粉末，研究了喷雾干燥和碳化反应温度对制备偏钨酸铵前驱体以及碳化钨的影响，前驱体粉末呈现均匀的球状形态，平均粒径为10~20μm，喷雾温度对影响粒径大小和分布影响小；400℃的进口温度下进行喷雾干燥，喷雾粉末仍然保持偏钨酸铵原来的基本组成不发生分解。

The method adopts the following steps: after mixed, phosphorus source, silicon source, aluminum source, an organic template agent, water and a precursor of the SAPO molecular sieve are hydrothermally crystallized for at least 0.1 hour at the temperature ranging from 110 to 260 DEG C to obtain the SAPO molecular sieve; wherein, the preparation method for the precursor of the SAPO molecular sieve has the following steps:, the molar ratio is 0.03 to 0.6 R:(Si0.01 to 0.98: Al 0.01 to 0.6: P0.01 to 0.6): 2 to 500 H2O; wherein, R stands for mixture solution of raw materials which is blended by the phosphorus source, the silicon source, the aluminum source, the an organic template agent and water of the template agent;, the mixture solution of raw materials prepared in step reacts at the temperature which is at least 50 DEG C lower than the crystallization temperature for at least 0.1 hour.

本发明通过采用包括以下步骤：将磷源、硅源、铝源、有机模板剂、水和SAPO分子筛前驱体混合后在110～260℃的温度下水热晶化至少0.1小时获得SAPO分子筛；其中SAPO分子筛的前驱体的制备包括以下步骤：将摩尔配比为0.03～0.6R∶(Si0.01～0.98∶Al0.01～0.6∶P0.01～0.6)∶2～500H 2 O，式中R代表模板剂的磷源、硅源、铝源、有机模板剂和水混合成原料混合液；将步骤制备的原料混合液在低于晶化温度至少50℃的温度下反应至少0.1小时的技术方案较好地解决了该问题，可应用于含氧化合物制烯烃催化剂的制备过程。

The nitrides with high specific surface area from oxide precursor can be prepared through temperature-programmed reduction via topotactic reaction in ammonia or nitrogen under strict reduction conditions.

在基本不破坏氧化物前驱体晶体结构和严格的氮化条件下，氧化物前驱体通过程序升温氮化经由&局部规整反应&可以制备出高表面积的过渡金属氮化物。

The large distribution of conjugation length was regarded as the reason of vanishing of the vibronic structure. Low costing MeO-PPV was prepared via modified Burn's method.

发现三种方法合成的前驱聚合物在转化初期有相同的PL光谱变化，说明这些前驱聚合物的共轭结构增长过程是相似的，并推测共轭长度分布宽是振动结构消失的原因。

As calcined at 900℃ for 1 hour, the final product of method A had not any impurity phase in its XRD pattern, but the final product of method B showed the impurities of YAP and YAM in its XRD pattern. The calcinations temperature should be higher than 1000℃ for the formation of pure YAG: Ce powder by method B.

由实验结果得知，以法所得前驱物经过900℃、1hr 下煅烧，即可得没有其他杂相的YAG：Ce粉末；而法所得到的前驱物，由X-ray分析结果中发现在低於900 ℃则会有其他中间杂相生成，需要在更高的温度如1000℃下才可以得到没有杂相的YAG：Ce 粉体。

The peroxide precursor of barium titanate and barium titanate nanopowder prepared were characterized to be BaTi(H2O2)2O3 by TGA-DTA, XRD, TEM, SEM, and XREDS.

借助TGA-DTA、XRD、TEM、SEM等分析测试手段，证实所制得的钛酸钡过氧化物前驱体为BaTi(H2O2)2O3，其煅烧产物纳米钛酸钡粉体的粒径在20～40nm，探讨并提出了过氧化物前驱体热分解法制备纳米钛酸钡的反应机理。

In this paper, a turbostratic CN precursor was prepared by means of pyrolysis of melamine, then it was treated by high temperature and high pressure. The pyrolysis process of melamine, mechanism of hydrogen elimination and the effect of catalysts on pyrolysis of melamine were studied. The crystal structures, bonding states and chemical compositions of CN precursor obtained by pyrolyzing melamine are analyzed by X ray diffraction, burning spectrum, scanning elecron microscope and Fourier transform infrared Spectroscopy.

本文采用三聚氰胺热解法制备了乱层石墨结构的碳氮前驱物并进行了探索性的高温高压实验；研究了三聚氰胺热解的工艺、去氢机理以及催化剂对三聚氰胺热解过程的影响规律；借助 X 射线衍射、燃烧谱、透射电镜和红外光谱等手段，对获得的碳氮前驱物进行了成分、晶体结构、价键结构的分析。

In this dissertation, novel solution routes have been developed to prepare tungsten trioxide and tungstate nanomaterials with all kinds of morphologies using low-cost, facile sodium tungstate as raw material.

利用一种简单的方法制备了钨前驱体的中空纳米球，然后煅烧此前驱体得到了三氧化钨纳米中空球，在煅烧过程中没有破坏它的形貌。

The results showed that functional nanometer ITO powders of 30-50nm size with dispersion performance can be prepared. The condition is that indium salt concentration is 88mmol/L, SnO2/In2O3 =5.3wt%, reaction solution PH value is 8, The precursor are thermally reduced at 450 ℃ under hydrogen gas ,at the sametime adding 6at.% KC1 salt to indium tin salts. Thus, satisfactory and stable dispersion of ITO particles in aqueous solution is obtained only through simple mechanical force.

KCl、反应铟盐浓度88mmol/L，掺杂比SnO_2/In_2O_3≈5.3wt%，维持PH值为8的反应条件下制备前驱体，前驱粉体在450℃，氢气气氛煅烧的条件下可生成功能性的具有很好分散性能的ITO粉末，粒径大小为30—50nm，此制备得到的粉体通过简单的机械分散可直接稳定的分散于水、醇介质，若通过分散剂处理后的分散体系可以稳定存在两个月以上。

Mesoporous tin dioxide (SnO2) was synthesized by thermal decomposition of the precursor obtained via a solvothermal method in the presence of SnCl4·5H2O, urea and ethanol.

采用溶剂热方法，以SnCl4·5H2O/尿素/乙醇三元体系合成了具有特定结构的前驱体，该前驱体经焙烧后得到了具有海绵状结构的介孔SnO2。

At the rear was an innovative combination transaxle with the gearbox, clutch, differential, and inboard-mounted drum brakes.

在后面是与变速箱，离合器，差的创新结合变速，和内侧安装鼓式制动器。

For more people can apprecaite and have the master work, there is reproduction painting appears in the market, the large various selection of paint,the high saturation of color plus the plentiful sfumato, to make the reproduction perfect copy and detail as original painting, so as to meet the requirment of amateurs who love art paintings,they do not need to pay high price to get classical paintings.

颜料色域广，色彩饱和度高，色彩层次丰富，图像色彩还原真实，能完美的复制原作，满足艺术爱好者欣赏，艺术爱好者们不用支付昂贵的价格就能拥有经典油画。