查询词典 precursor

Research result indicated that the cooperative effect between swell and precursor is main factor for the nanoparticle loaded in Nafion, and moreover, polarity of solvent and water content in Nafion also affects the load largely. To improve away the surface concentration of CdS nanocrystal on two side of membrane for general preparation, thioacetamide was first used as a precursor instead of inorganic sulfur source(H2S and Na2S) in synthesis of CdS nanocrystal. The assembly mechanism for several sulfur source had been studied, and CdS/Nafion with the character of homogeneous disperse had been prepared, which is fit for mass transmission in photocatalitic reaction. Following the investigation of several crystallizing way, simple and reliable hydrothermal-crystallizing was found. According to this way, maximal TiO2 load in Nafion achieved 43%. Activity of TiO2/Nafion or CdS/Nafion as a photocatalyst was explored initially for disintegrating liquid contamination. Maximal decompose rate achieved 86% under condition of this research.

研究结果表明：Nafion膜对纳米粒子负载量的主要影响因素是溶胀作用与前驱体协同效应，同时溶剂极性和薄膜含水量对负载量也影响相当大；本课题首次使用硫代乙酰胺代替传统无机硫源（H2S、Na2S）合成CdS纳晶，研究了各种硫源的组装机理，克服了常规技术存在的CdS纳晶趋于膜表面富集的缺点，得到了有利于光催化传质需要的体相均匀分布CdS/Nafion；研究了多种Nafion膜内纳米粒子晶化途径，找到了简单可靠的水热晶化法，TiO2纳晶最高负载量达43％；初步探索了TiO2/Nafion、CdS/Nafion作为光催化剂降解水中模拟污染物的活性，在本实验条件下最高降解率达86％。

The amplified fragment was inserted into pRSET-A to generate the first double repeat of the precursor gene. By utilizing a pair of isocaudamer BamH I and Bgl II sites, and another downstream Hind III site of plasmid pRSET-A, following a series of simple double digestions and ligation of the resulted products, a series of repeat (3, 4 and 6) precursor peptide fragment genes were derived.

本实验设计一对两侧含编码疏水性氨基酸密码子的引物，经过扩增前导序列10~34aa基因序列，并重新克隆入质粒pRSET-A构建串联二聚体后，再利用质粒pRSET-A的BamH I / Bgl II同尾酶克隆位点，经一系列简单的酶切和连接，快速构建这一前导肽中不含组氨酸标签序列的串联多聚体基因，并成功表达其六聚体重组蛋白。

Iraq's procurement efforts include equipment that can filter and separate micro-organisms and toxins involved in biological weapons, equipment that can be used to concentrate the agent, growth media that can be used to continue producing anthrax and botulinum toxin, sterilization equipment for laboratories, glass-lined reactors and specialty pumps that can handle corrosive chemical weapons agents and precursors, large amounts of vinyl chloride, a precursor for nerve and blister agents, and other chemicals such as sodium sulfide, an important mustard agent precursor.

伊拉克采购的设备包括可过滤和分离生化武器中微生物和毒素的设备；可用于为炭疽病毒和肉毒菌病毒集中药剂和生长媒体的设备；实验室杀菌设备；可处理腐蚀性化学武器药剂、前体、乙烯基氯化物及其他化学药剂(如钠硫化物，芥子气药剂的前体)的玻璃线纹反应堆和专业水泵。

Preparation of ultra fine MgNi2 powder via reduction of the oxide precursor was systematically studied.The precursor was prepared with nickel nitrate,magnesium nitrate and glycin as start materials by combustion method.

以Mg(NO3)2和Ni(NO3)2为原料，用甘氨酸作为氧化剂，采用燃烧法制备约50 nm的混合金属氧化物前躯体，再在H2气氛保护下的管式炉中用CaH2还原制备MgNi2合金。

Many introns are contained in precursor mRNAs of eukaryotic cells, which are usually cut off in the processing of precursor mRNAs.

真核细胞的前体mRNA中一般都含有大量的内含子，它们在前体mRNA的加工过程中将被剪除。

The millimetersized tubular crystal selenium was first prepared. By studying the process of treating selenium in ethylenediamine, we proposed the mechanism of the preparation of selenides under solvothermal condition. The selenides came into being from the reaction of metal ions with Se〓, which was obtained by the amine attacking selenium. Moreover, a new precursor to prepare nanocrystalline selenides at room temperature was obtained. From this precursor, we have prepared nanocrystalline silver selenides, copper selenides, lead selenides and cadmium selenides nanorods.

首次报道了采用溶剂热处理的方法制备出厘米尺度的管状结构硒晶体；通过对硒粉在乙二胺中的溶剂热研究，初步探讨了以单质硒为硒源的溶剂热合成硒化物的反应机理应是硒受胺类的亲核进攻变成Se〓而进一步形成相应的硒化物；获得了合成硒化物纳米晶的前驱物，并在室温条件下合成了硒化银、硒化铜、硒化铅纳米晶和硒化镉纳米棒等。

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。

But when Fe/D113 precursor is pyrolysed in the range of 400-700℃, the crystal structure of the iron particle is different. The products are mainly iron oxides andα-Fe as Fe/D113 precursor pyrolysed at 500℃, and as the pyrolytic temperature increases to the range of 600-700℃,α-Fe and Fe_3C are observed. Meanwhile, Al_2O_3、MgO、MgAl_2O_4 were observed in Al/C, Mg/C, Al-Mg/C which were prepared from D113 resin at 1000-1300℃.

而在同样的条件下热解载铁树脂(Fe／D113)，热解产物中铁的晶体结构与热解温度有关，400℃热解产物为铁的氧化物；500℃热解产物为体心立方结构的单质铁；600-700℃的热解产物为bcc单质铁和铁的碳化物(Fe_3C)。1000-1300℃热解含Al、Mg及Al-Mg的D113树脂制得的Al／C、Mg／C、Al-Mg／C材料中Al、Mg主要以Al_2O_3、MgO、MgAl_2O_4形式存在。

The precursor was prepared with ammonium zinc phosphate and lithium carbonate as materials via solid state reaction at room temperature.The target product was got after baking the non crystals precursor of the compound.

人们从对有层状结构的磷酸盐性质的研究中获知，大量具有层状结构的磷酸盐化合物能够承受离子交换而且还具有良好的催化性能。

The average liter was 30% higher than original strain during normal fermentation. Using propionate as half precursor instead of 01 precursor, the fermentation titer of Rh 109-2 does not reduce, and the content of MDMA_(1) increases.

正常发酵时，Rh 09－二的发酵水平比出发菌株提高了30％：当采用丙酸盐替代原有的of前体的一半进行补料时，Rh 09－2的发酵单位没有降低，而 MDMA；的含量略有提高，从而降低了发酵成本。

We were cousins—his grandfather was King of Scots,and his great-grandfather was Henry VII of England.

我们是堂姐弟——他的祖父曾是苏格兰国王，他的曾祖父是英格兰的亨利二世。

I do want to help you, but I am in a quandary now!

我是想帮你，但是我现在左右为难啊！