查询词典 membered

On the basis of Raman and FTIR spectra research on melt structure and water solubility mechanism in albite glasses, we can make the following conclusions:(1) Higher pressure (1bar-2. 0GPa) can lead to below frequency region (50-650cm〓) shift to higher frequency and become narrower, and result in high frequency region (850-1300cm〓) move to lower wave number and become narrower at the same time. These are consistent with the decrease of average T-O-T angle and distribution scope of bond angles (0). In addition, the intensity of 580cm〓 band decrease with increase of pressure and the changes are obvious while pressure is in the range of 0.8-1. 0GPa. And these result from the"collapse"of the planar three membered -containing rings within the glass structure.

通过对高温高压下钠长石熔体结构及水在钠长石熔体中溶解机制的Raman和FTIR光谱实验研究，可以得出以下结论：(1)随着压力升高(1bar-2.0GPa)NaAlSi〓O〓熔体玻璃Raman光谱的低频区(50-650cm〓)不断变窄并向高频方向移动，同时高频区(850-1300cm〓)不断变窄且向低频区方向移动，这表明随着压力升高T-O-T键角不断减小，并且分布范围变窄，T-O-T键角这种变化从而可使T-O键的力常数减小，导致键强减弱；另外，580cm〓谱峰强度随着压力升高不断减弱，并在0.8-1.0GPa时最为显著，这是由于在0.8-1.0GPa时包含的平面三元环结构的"垮塌"造成的。

A five-membered heterocyclic ring compound, C4H5N, having an odor similar to chloroform. It is the parent ''.'compound'.

叽咯一种五倍杂环混合物，c4h5n，气味与三氯甲烷相似，是血红蛋白，叶绿素和其他多种''。

In Chapter 5,the pyrolysis of substituted six-membered ring model compound 4-methyl pyridine has been investigated.Instead of detail theoretical analysis of the reaction mechanism,the general results have been proposed from the products distribution and the combination of the pyrolysis investigation of its analogous pyridine.The major products are H_2,C_2H_2,C_4H_2,C_3H_3N and HCN,here HCN is not a primary initial product at low extent of decomposition.The mole fraction profiles of products have been obtained from the near threshold ionization.The pyrolysis of 4-methyl pyridine is initiated from the methyl abstraction and hydrogen abstraction procedures which are associated with the understanding of the soot formation and the NOX precursor correspondingly.

主要产物为H_2，C_2H_2，C_4H_2，C_3H_3N和HCN，其中HCN为非低温时的热解产物；通过近阈值电离并导出物种随温度变化的摩尔分数曲线，更详细地定量地描述了产物随温度的变化。4-甲基吡啶热解主要从母体脱甲基和脱氢两个初始反应出发，一种趋势是形成大质量数的苯并或杂环的多环化合物，有助于了解炭黑形成过程中的复杂化学过程；另一趋势是开环生成小的碳氢和腈类物质，实验得出的含氮物质的种类及随温度变化有助于了解NO_x的前驱物质的形成及其变化规律。

The results of experiments show that the random chain scission of maleated PHB obeys the six-membered ring ester decomposition process.

结果表明，PHB-g-MA的热分解机理与PHB相同：在高温条件下，PHB分子链的酯基部分形成六元环结构，断链时夺取亚甲基氢，生成羧基和双键两种端基。

The results show that there are eight reaction channels, corresponding to eight transition states, in the reaction process. The main parts of all transition states are non-planar five-membered ring, in which the geometry of Z -benzaldoxime and E -benzaldoxime is maintained partially, but the bond length, bond angle and charge are all changed.

结果表明，在苯甲醛肟与炔丙醇加成反应过程中， 8个可能反应通道的过渡态中均形成非平面五元环结构，其中苯甲醛肟的 Z 、 E 构型特征得到了部分保留，但主要部分的键长、键角均发生了变化，电荷也进行了重新分布。

This indicates that the IE of these aza-aromatic bicyclic molecules increases with the number of the N atoms. This finding may be attributed to the nature and the N atoms in the five-membered ring.

表示因为氮原子具有较大拉电子的能力，因此五角环上具有较多的氮原子会使得分子具有较高的游离能。

The second part is about that five-membered rings compounds were synthesised using aromatic aldehyde,α-bromoketone and imine ester in the present of zinc power.

2以芳香醛，α-溴代苯乙酮与氨基酸酯亚胺类化合物在金属锌粉的作用下，生成一系列的四氢吡咯化合物。

They suggested that radicals with a double bond 13 to the carbon bearing the peroxy groups (which can only arise from acids containing more than two double bonds) cyclize to form peroxides with five-membered rings.

他们认为连接过氧基的碳原子有一个双键的游离基(只有多于两个双键的酸可形成)环化形成五元环的过氧化物。

In the second part of this thesis, a formal [2+2] cycloaddition ketenes and dialkyl azodicarboxylates was studied. We found that by adjusting the substituents in the diazenes, the reaction mode can be completely switched, and furnish four-membered-ring products, aza-b-lactams, the enantioselectivity was up to 91%.

经研究发现，通过对偶氮化合物取代基团的改变，我们可以实现[4+2]环加成反应到[2+2]环加成反应的转变，在手性氮杂环卡宾的作用下，对具有各种取代基的烯酮都可以很好的产率得到氮杂b-内酰胺，其对映选择性最高可以达到91%。

The molecule of taxol is an extremely complex diterpene with a taxane ring structure fused with a four-membered oxetane ring, an ester side-chain at position C-13 and a benzoyl side-chain at the C-2 position Fig.

紫杉醇分子是一个极其复杂的四环二萜类化合物：一个紫杉烷环加一个四个元素组成的氧烷环，在C-2和C-13上还分别有一个苯氧基和酯基侧链。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。