查询词典 conformers

In chapter 2, we through search the stable conformers of asparagine and examine the properties of the stable conformers using ab initio and DFT methods.

第二章中我们使用从头算方法和密度泛函理论对天冬酰胺在气相中的稳定构型进行了系统的寻找。

We calculate the vertical and adiabatic ionization energies, vertical and adiabatic electron affinities of asparagine conformers.

我们计算了天冬氨酸的垂直和绝热电离能、垂直和绝热电子亲合能。

The positions where the electron ionizes are quite different as the asparagine conformers with various H-bonds.

天冬酰胺不同类构型有不同的氢键类型，其电子电离的位置也很不一样。

Then, have explored the conformer interconversion among all glycine conformers, and discussed some arguments about glycine conformers' symmetries.

研究所有的苷氨酸构象异构体之间相互转换，并且探讨了苷氨酸构象异构体的对称性问题。

We thorough search the stable conformers of aromatic amino acids and arginine and examine the properties of the stable conformers using ab initio and DFT methods. The properties examined include the characteristics of intramolecular interactions, IR and UV spectra, temperature dependent conformer distributions, electron attachment and ionization energies, protonation/deprotonation processes.

木论文对芳香型氨基酸和精氨酸进行了理论研究，研究的性质包括几何结构、电子结构、构刑分布、电离能和电子亲和势、质子化过程、红外谱、紫外谱以及分子内相互作用等方面。

Furthermore, the NBO calculation implies that relative stabilities of all 15 conformers can be attributed to the steric and hyperconjugation effects. In addition, the result derived from G3MP2 shows that the heats of formation of all conformers are positive and heats of formation of ring conformers are greater than those of chain conformers.

而且，NBO的立体和超共轭分析表明立体交换排斥能和超共轭作用对这些分子的相对稳定性起了重要作用。G3MP2计算结果表明氮氢化合物的生成热均为正，并且环状分子的能量和生成热都高于链状分子。

In this thesis,the AM1,MNDO,MINDO/3(mainly AM1)and INDO/S-CI semiempirical MO methods were used toinvestigate the excited-state intramolecular protontransfer reactions of salicylic acid derivatives—salicylic acid,methyl salicylate,salicylaldehyde,o-hydroxyaceto-phenone,salicylamide and 3-hydroxy-picolinamide (6 conformers and 2-3 anion species);2-(2'-hydroxy-5' methylphenyl) benzotriazole(4 conformers),2-(2' hydroxyphenyl) benzimidazole (3 conformers and 3anion species),Bis-2,5-(2-benzoxazolyl)hydroquinone(3 conformers),2-(2'-hydroxyphenyl)benzothiazole(2conformers) and 7-azaindole dimer (2 conformers).Theinvestigations were described as follows.Geometry optimization,relative stability andhydrogen bonding energy First,for sylicylic acid derivative molecules,the AM1,MNDO and MINDO/3 methods were used toinvestigate ground-state geometry optimization,energies,relative stabilities and hydrogen-bondingenergies on the five kinds of the molecules(designing 6 conformers and 2-3 anion species).Comparing with experimental data,the optimizedgeometry,the order of stability,the hydrogen-bonding energies and the distances between O-O in O-H..O hydrogen bonds by AM1 method were in agreementwith the experimental data,however,the C-C bondlengths optimized by MNDO and MINDO/3 were longer,C-O and O-H bond lengths were shorter;for C-N bondlengths,the results opitimized by MNDO method werethe same as those by AM1 method,nevertheless the C-Nbond lengths given by MINDO/3 method were muchshorter.For some sylicylic acid derivatives(e.g.methyl salicylate,salicylamide),the order ofstabilities on the conformers given by MNDO andMINDO/3 methods were not in agreement with theexisting conformers deduced by experimental methods,and the hydrogen bonding energies calculated by MNDO.and MINDO/3 methods were smaller.Second,the studyon the other systems found that the optimizedgeometry of the proton-transfered product with INDOmethod could not be obtained,only could theoptimized geometry of reactant be obtained,and thecalculated hydrogen bonding energies were greater.Many results of calculation indicated that the studyon the excited-state intramolecular proton transferreaction system using AM1 method was suitable andreliable.

本论文用AM1、MNDO、MINDO/3（主要是AM1）和INDO/S-CI半经验分子轨道方法对水杨酸衍生物系列——水杨酸、水杨酸甲酯、水杨醛、O-羟基乙酰苯酮、水杨酰胺和3-羟基吡啶酰胺（6种异构体和2-3种阴离子）；2-（2'-羟基-5'-甲基苯基）苯并三〓唑（4种异构体）；2-（2'-羟基苯基）苯并咪唑（3种异构体和3种阴离子）；2，5-二间氮杂氧茚氢醌（3种异构体）；2-（2'-羟基苯基）间〓杂硫茚（2种异构体）和7-〓吲哚二体（2种异构体）的激发态分子内质子转移反应在以下几个方面进行了较系统的理论研究：几何构型优化和相对稳定性及氢键能首先以水杨酸衍生物系列分子为例，用AM1、MNDO和MINDO/3方法考察了5种分子（每种分子设计6种异构体和2-3种阴离子）的基态几何构型优化，能量、相对稳定性和氢键能计算，通过和实验数据进行比较，AM1方法给出的优化几何构型、稳定性次序、氢键能和O—H。。。O氢键的0—0距离与实验数据吻合最好，MNDO和MINDO/3方法优化的C-C键长偏长，C-O键和O-H键长偏短；对于C-N键长，MNDO和AM1优化结果差别不大，而MINDO/3给出了过短的C-N键长，MNDO和MINDO/3方法给出的有些水杨酸衍生物分子（如水杨酸甲酯和水杨酰胺）异构体的稳定性次序和实验上推测的可存在异构体结果不一致，MNDO和MINDO/3方法给出的氢键能偏低，对其他体系的研究发现INDO方法常常不能得到质子转移产物的优化几何构型，只能得到反应物的优化构型，并且估算的氢键能偏高，大量的计算结果表明AM1方法对本论文研究的激发态分子内质子转移反应体系是适宜和可靠的。

Careful analyses reveal the connections between the structures of tripeptide and dipeptides or amino acids.Based on the method proposed for dipeptides,a method for finding all important tripeptide conformers utilizing dipeptide and amino acid conformers is put forward.

分析给出了三肽稳定构型和相应的二肽及氨基酸稳定构型间的密切联系，基于二肽构型的寻找方法，发展了一种使用二肽和氨基酸稳定构型来高效寻找三肽稳定构型的方法。

The calculations resulted in prediction of four different stable conformers of cGMP and eight different stable conformers of cGMPH and their relative Gibbs free energies in the gas phase and aqueous solution.

计算的结果预测了在气相和溶液中cGMP的四种不同的稳定构象及cGMPH的八种不同的稳定构象和它们的吉布斯自由能。

All of the computational results consistently demonstrate that in gas phase the predominant conformers of cGMP and cGMPH are the cGMP-chair-syn and cGMPH-chairl-syn conformers, respectively.

所有的计算结果一致的显示，在气象中cGMP和cGMPH分别主要以cGMP-chair-syn和cGMPH-chairl-syn构象存在。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。