查询词典 first-order reaction

The carbons in explosives are decomposed into gas-like carbon atoms in the detonation reaction zone, then unoxidized carbon atoms coagulate into carbon liquid droplets and finally consolidate into solid diamonds The new mechanism differs from one conclusion that carbons of explosives are at first transformed into solid graphites, then into diamonds, and also differs from the conclusion that gaseous carbons coagulate into liquid droplets in the reaction zone, then crystalize into diamonds in Taylor rarefaction wave zone.

修正了有关炸药中的碳在反应区内先转变为石墨，然后石墨再发生相变生成金刚石的论点以及认为在反应区内气态碳凝聚为碳液滴，液滴在Taylor稀疏波区凝固成金刚石的论点。

A one-step method for the synthesis of aromatic indolizine derivatives byintramolecular 1,5-dipolar cyclization reaction of 2-(2-arylethenyl)pyridinium N-ylidesin the presence of an oxidant has been studied for the first time. In the presence ofelectron-deficient olefins, however, 2-(2-phenylethenyl)pyridinium N-ylides underwent1,3-dipolar cycloadditions and then aromatized in situ by TPCD to produce indolizinederivatives, indicating 1,3-dipolar cycloaddition proceed more readily than 1 ,5-dipolarcyclization in these conditions. Pyridinium disubstituted N-ylides, readily obtainedfrom corresponding pridinium and β-chlorovinyl ketone, underwent thermalintramolecular 1,5-dipolar cyclization to give indolizine derivatives easily.Indolizinecarbaldehyde derivatives were synthesized starting from 2-pyridinecarbaldehyde in four-steps involving 1,3-dipolar cycloaddition reaction.

本文首次研究了2-(2-芳基乙烯基)吡啶N-叶立德在氧化剂存在下的分子内1，5-偶极环化反应，采用一锅法合成了中氮茚衍生物；研究了这些N-叶立德的1，5-偶极环化和1，3-偶极环加成反应的选择性，发现当有缺电子烯烃存在时，优先进行1，3-偶极环加成反应，而不再发生分子内1，5-偶极环化反应；由β-氯乙烯酮方便地得到了烯丙基N-叶立德，他们在加热时进行分子内1，5-偶极环化反应而得到中氮茚衍生物；由2-吡啶甲醛为起始原料，通过1，3-偶极环加成反应等四步反应，得到了重要的中氮茚甲醛衍生物，这些反应都具有条件温和和操作简便的特点，是合成中氮茚衍生物的新方法。

Generally, there are two stages throughout the reaction of Si〓N〓 and interlayer. At the first stage, the liquid Cu enwraps Nb phase, and Nb diffuses into the Cu. The reaction layer of NbN and Nb〓Si was caused between Nb and Si〓N〓.

第二阶段，Cu全部熔化，Ni向液态金属中扩散溶解，形成Cu-Nb-Ni液态合金，液态合金中的Nb、Ni向Si〓N〓界面扩散并与之反应形成由NbN、Nb〓Si和Ni〓Si组成的反应层。

The first reaction mixture consisted of 5uL 10×PCR buffer,0.5uL 20mmol/L dNTP,1uL of primer F1、R2(25umol/L),0.5uL Taq (2.5U),FTA filtering,42μL of double-distilled water,the whole system was 50μL;The reaction was run under the following conditions:DNA pre-denaturation at 94℃for 5 min;DNA denaturation at 94℃for 30 s,primer annealing at 58.8℃for 1min, extension at 72℃for 30s,for 25 cycles,and extension at 72℃for 5min.

第一轮适宜反应体系分别为：5uL的10×PCR buffer，0.5uL的20mmol/LdNTP，引物F1、R2各1uL(25umol/L)，0.5uL的Taq酶(2.5U)，含有基因组DNA模板的滤膜，用去离子水补足到50 uL。

Then we completed the first total synthesis of-Plakoridine A using Eschenmoser couping reaction as akey step. During the synthesis we found the choice of protecting groups and the configuration of the chiralcenter of the substrate play an important role to the key Eschenmoser reaction,so we think our successwould be of guide for synthesizing other polysubstituted pyrrolidines or piperidines.

在论文的第一章中，我们先以易得的对羟基苯乙酸乙酯为原料经多步反应制得了所需的β氨基酸酯，然后利用立体选择性的Aldol缩合反应和内酰胺化反应制得了Plakoridine Alactam，随后，以Eshenmoser缩合反应为关键步骤完成了生物碱-Plakoridine A的首次不对称全合成。

If the content of SiH〓 kept constant, the laser energy value of threshold that decomposed SiH〓 increased linearly at first, but when the gas flux exceeded 100ml/min, the laser energy value of threshold increased slowly because the coaxial Ar could not"suppress"the reaction flame which leaded to radial dilation of reaction gases and increasing the effective absorption to laser energy.

在反应气体中SiH〓含量不变的情况下，随着反应气体流量的逐渐增加，可以引发硅烷分解的激光能量阈值一开始成线性增加，当流量大于100ml/min以后，由于同轴Ar不能有效的&压住&反应焰，导致反应气体的径向扩张，增加了对激光能量的有效吸收面积，因此激光能量阈值的增加减缓。

Our group first reported a novel dialkylation reaction of alkyl zinc iodides with aromatic aldehydes and an olefination reaction of benzyl zinc bromides with aromatic aldehydes respectively.

我们实验室分别首次报道了在过渡金属络合物催化下带官能团有机卤化锌试剂与芳香醛的双烷化反应和烯基化反应。

Such textures suggest the development of reaction:① Gt〓+Cpx〓+Qz→Opx〓+Pl〓 and ② Gt〓+Cpx〓+Qz+H〓O→ Hb〓+Pl〓 Reaction ② is the first discovery in the granulite series in our country, the later cooling stage of M〓 was recognized by growth of yellowish green hornblende of amphibole facies at the expense of various pyroxenes.

在麻粒岩系中发现同一石榴石晶体边缘不同部位同时发生Gt+Cpx+Qz＝2Opx+pl和5Gt+5Qz+2H〓O＝2Hb+Pl等典型的降压反应，这一现象在国内麻粒岩系中也属首次发现。并通过这些特征变质反应实验资料的深入研究，确定了它们的平衡条件及所代表的P-T演化意义。

The theory of the reaction wheel is introduced at first,then the invariability theory of disturbing compensation and the math description of feed forward control.are recommenoled feed forward control and dead voltage compensation are added in the model of reaction wheel control.

中文摘要：对星载二维转台中反作用轮的控制技术进行了研究。介绍了反作用轮的作用原理，给出了扰动补偿的不变性原理和前馈控制的数学描述。

The reaction of the degradation is a first degree , and a constant of reacting rate is 0.5378 mmols/ L.h. The control of step is inside difussion for the process. A series of experiments had been done to remove SO2 with the biochemical reaction system.

脱硫菌通过将硫酸根离子还原成还原态的硫化物然后再固定到蛋白质降解SO2气体，固定化微生物生化降解SO2反应活化能为39.5kJ/mol，降解反应速度为一级反应，反应速度常数为0.5378mmol/L.h，内扩散为过程控制步骤。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。