查询词典 reaction formation

Applications of thionyl chloride in pharmaceutical and pesticide sectors and application developments in organic synthesis reaction and ring formation reaction are introduced.

氯化亚砜又名亚硫酰二氯、氯氧化硫，是一种重要的无机精细化工产品，在医药、农药、染料、化工等行业及有机合成反应中具有广泛的应用。

Analysis based on the experimental results demonstrated the plausible reaction mechanism is that vit C first converts Cu(superscript 2+) to its reduced state and vit C becomes vit C radical itself, thereby stimulating the formation of peroxyl and alkoxyl radicals, and bimolecular reaction of peroxyl radicals results in (superscript 1)O2 production in the systems studied.

根据实验观察的结果，分析了这一体系中(上标 1)O2形成的可能途迳，认为首先是维生素C将Cu(上标 2+)转变为还原态，而自身失去一个电子转变为维生素C自由基，从而刺激了过氧自由基和烷氧自由基的形成，过氧自由基的双分子反应很可能就是体系内(上标 1)O2产生的反应机制。

For double jet method, effects of used solvent, shape of stirrer, adding reactant position, reaction temperature, excessive silver ion concentration in reaction solution and adding rate on the nucleus formation, and growth of silver behenate crystal were systematically studied.

本文分别采用单注沉淀法和双注沉淀法制备了山嵛酸银晶体，通过对两种制备方法的对比及优选，最后确定双注沉淀法更适合制备细粒径的山嵛酸银，通过采用SEM、TEM等对山嵛酸银晶体形貌的表征发现，制备山嵛酸银所使用的溶剂、搅拌方式、加料的位置、反应温度、反应初始液中银离子浓度及加料速度等，均对山嵛酸银的晶体成核与生长有一定的影响。

The effect of zeolites ion-exchanged by transition metals on thermal catalytic cracking reaction is studied. The product distributions of the cracking reactions catalyzed by theβor ZSM-5 zeolites exchanged with transition metals are different from that catalyzed by corresponding Hzeolites, which means the mechanism of cracking reactions has varied. Group Ⅷ metals Fe, Co, Ni and Cu, Zn are shown to be of strong catalytic activity of oxidative dehydrogenation, while Ti and Cr are not of oxidative activity. Catalyzed by zeolites or catalyst containing Ag, conversion of thermal catalytic cracking reactions and the yield of ethylene increase while the yield of propylene does not decrease. Silver can not only promote the formation of carbonium ion, but also convert carbonium ion into free-radical via redox reaction. The weak adsorption of olefins on silver reduces the occurrence of hydrogen transfer and dehydrogenation. As a result, the yield of light olefins is favored by silver in the catalyst.

采用过渡金属交换的分子筛作为催化剂，进行催化热裂解制取乙烯的反应，研究发现，在β沸石分子筛和ZSM-5分子筛中引入过渡金属后，催化热裂解反应的产物分布与相应的氢型分子筛相比有了较大的变化，说明过渡金属的加入对于催化热裂解反应的机理具有影响，Ⅷ族金属如Fe、Co、Ni和第Ⅰ、Ⅱ副族Cu、Zn表现出较强的氧化脱氢活性，产物中氢气、焦炭的产率很高，Ti、Cr则未表现出氧化作用：分子筛及催化剂中引入银后，催化热裂解反应的转化率和乙烯的产率有了提高，丙烯产率没有很大的变化，说明银在催化热裂解反应中能够促进正碳离子的生成，又有可能通过氧化-还原作用部分改变反应机理，促进了自由基的生成，并且由于银对烯烃的吸附很弱，其氢转移反应和脱氢、加氢活性比较低，有利于烯烃产率的提高。

Thiol groups were good to be used in functionalizing gold nanoparticles, and ester bond formation and breakage played the major role in this research. Thioctic acid and 11-mercapto-1-undecanol were used to functionalize the gold nanoparticles and form ester bond by using the carboxylic acid group on thioctic acid and the hydroxyl group on 11-mercapto-1-undecanol. Concentrated sulfuric acid was used to be the catalyst in this reaction, and sodium hydroxide was added for the proceeding of the reverse reaction.

硫醇官能基在金奈米粒子的修饰有很好的效果，利用带有硫醇官能基之tioctic acid 与11-mercapto-1-undecanol (11-MUDO)分子修饰在金奈米粒子上，并使TA上之羧基和11-MUDO上之羟基脱水生成酯化键，浓硫酸则是反应中的催化剂，而氢氧化钠则可促使系统进行逆反应。

To assess the thermal contribution from oxidation reaction, the standard formation enthalpes of all reactants and products were used to calculate the oxidation enthalpies. It could be found that all oxidation reactions were exothermic. And oxidation played a more important role during the toluene trinitration at high temperature, because the reaction temperature of toluene trinitration is the higher than mononitration and dinitration, and the temperature coefficient of oxidation is higher than that of trinitration too.

为了考察不同阶段氧化副反应对反应放热的贡献，用反应物和产物的标准生成焓推得氧化反应的理论反应热，计算结果表明，各段硝化的氧化副反应均为放热反应，其中三段硝化反应由于反应温度最高，氧化反应的温度系数比硝化反应高，故氧化副反应对三段硝化影响最大。

New reactions found in this program include: photoinduced regioselective free radical addition to aromatic imines;photoinduced Dielse-Alder reactions of aromatic imines for synthesis of tetrahydroquinoline derivatives;Photoinduced radical cation mediated selective ring opening reaction of epoxides;Formation of novel macrocyclic crown ethers by photoinduced reaction of diazonaphthaquinones;photoinduced selective desilylation of silyl ethers.

用这种方法成功的发现了下列在有机合成中有意义的新反应：(1)光诱导产生的自由基正离子诱导的自由基对芳香亚胺的区域选择性加成反应；(2)用光诱导的芳香亚胺的Diels-Alder反应合成四氢喹啉衍生物；(3)经光诱导产生的自由基正离子基诱导的环氧化物选择性开环反应；（4）重氮萘酮在环醚中经光诱导反应形成新奇的大环冠醚；（5）硅醚的光诱导选择性脱硅基反应。

Nanocrystalline zinc phosphate tetrahydrate was synthesized by solid-state reaction at ambient temperature using Na3PO412H2O and ZnSO47H2O as regents. The enthalpy of reaction and the standard enthalpy of formation of zinc phosphate tetrahydrate were studied by microcalorimeter.

以Na3PO412H2O和ZnSO47H2O为原料，采用室温固相反应制备纳米四水磷酸锌，用微量热法研究该反应的反应焓和四水磷酸锌的标准摩尔生成焓。

The presence of isopropanol in the crystallization process is beneficial for the formation of small Silicalite-1 nanocrystals. The rearrangement reaction results on the different Silicalite-1 indicate that the rearrangement reaction takes place at the external surface of the crystallites as well as in the mouths of zeolitic pores, but not inside the zeolitic pores.

制备条件对Silicalite-1的催化行为影响较大，在由硅酸乙酯水解老化后的溶胶中添加异丙醇可以促进小晶粒Silicalite-1的生成，改变模板剂的用量、晶化温度和时间等可以合成不同晶粒尺寸和形貌的Silicalite-1纳米晶。

Results indicated that reaction moved according to de novo synthesis mechanism with the increase of oxidation ability of MFA, while increasing chlorinating ability moved reaction towards precursor formation mechanism.

结果显示，模拟飞灰氧化性的增强使反应向从头合成反应机制的方向移动，氯化性的增强使反应向前驱物反应机制反应方向移动。

Since historical times,England ,where the early inhabitants were Celts, has been conquered three times .

从有历史以来，英国，在此地早期居住的是凯尔特人，已经被征服了三次。

Bluetooth OBEX File Transfer Enables the sending and receiving of files on your phone via Bluetooth.

蓝牙OBEX文件移动允许经过蓝牙传送和接受文件。。。。