异构体

From the PESes, a total of fourteen glycine conformers, including a new conformer, were found.

从势能面上，取得了总共14个苷氨酸构象异构体，其中包括取得一个新的苷氨酸构象异构体。

These results show that the dual fluorescence of 4-AHBO (5-AHBO) is produced by its different tautomers, hut not by the same isomer: the long wavelength emission is from the keto tautomer, and the short wavelength band is produced by four kinds of enol isomers.

结果表明，4-AHBO(5-AHBO)的双荧光不是由同一种异构体发射的，而是来源于不同异构体的发射：长波区的荧光由酮式构型发射，短波区的发射则可能由四种醇式异构体共同产生。

A rearrangement model for the complex and its isomers of the2+ was proposed, in which there could be two competed steric courses with the trigonal bipyramidal intermediate or intermediates.

利用[Co(3，3-tri)Cl]2+体系配合物及其异构体结构模型提出了一个2+型的配合物及其几何异构体相互转换所遵循的重排机理模型。认为在该类型配合物异构体转化过程中同时存在两个竞争途径，其中间过渡态或中间体分别为三角双锥或四角锥形式。

The structure and stability of all possible isomers of C50X(X=SiH2, PH, S) were investigated by ab initio HF/3-21G calculations. The calculation results indicate that the preferred position for cycloaddition of SiH2, PH, and S on C50 is consistent, i.e. on the C3-C4 and C4-C4 sites of C50, and the resultant most stable cycloaddition isomers are [5,6]-closed and [5,5]-closed structures. The main driving force governing the stability of the C50X(X=SiH2, PH, S) isomers is the strain, or the conjugative effect, or the combination of strain and conjugative effect, depending on the addition positions and the types of the attacked C-C bonds.

用从头算HF/3-21G方法研究了C50的环加成衍生物C50X(X=SiH2， PH， S)所有可能的异构体的结构与稳定性，计算结果表明，SiH2基团、PH基团与S原子在C50上环加成的优先加成位置相同，都为C3-C4类键和C4-C4类键，并且相应形成[5，6]-闭环和[5，5]-闭环结构的最稳定异构体；决定C50X(X=SiH2，PH，S)各异构体稳定性的主要因素，因加成位置以及发生加成反应的C-C键的单双键类型的不同，可能是张力、共轭效应或者二者的共同作用。

Theoretical studies on various geometrical structures of Hypophosphorous acid were carried out using DFT theoretical methods,at the B3LYP/6—311++G** level.Intramolecular proton transfer isomerization has also been studied using the intrinsic reaction coordinate.

采用量子化学密度泛函B3LYP方法，在6—311++G**基组水平上全优化得到了硫代次磷酸的硫酮式和硫醇式两种构型异构体以及相应的对映异构体，同时对分子内质子转移异构化反应微观机理进行了理论分析。

Theoretical studies on various geometrical structures of Hypophosphorous acid were carried out using DFT theoretical methods, at the B3LYP/6-311 ++ G(superscript **) level. Intramolecular proton transfer isomerization has also been studied using the intrinsic reaction coordinate.

采用量子化学密度泛函B3LYP方法，在6-311++G基组水平上全优化得到了硫代次磷酸的硫酮式和硫醇式两种构型异构体以及相应的对映异构体，同时对分子内质子转移异构化反应微观机理进行了理论分析。

In the 29 Aroma material studied, the content of the material having important effect such as norambreinolide, octadecanoic lactone(1), octadecanoic lactone(2), octadecanoic, 8,15-labdanum-1-ol,8,12-external oxidative labdanum-14-en-2-ol(1), 8,12-external oxidative labdanum-14-en-2-ol(2), 8,13-external oxidative labdanum-14-en-13-one(1), 8,13-external oxidative labdanum-14-en-13-one(2) Dihydroactinidiolide, solanone, norsolanone have Significant increasing trend in the aging, the peak of the content of material appear in the 18~21 months in the aging process.

在所测定的29种香气物质中，对香料烟特征香气有重要影响的香味物质如降龙涎香内酯、硬尾内酯2种异构体、硬尾醛、8，15－赖百当醇、2种8，13外氧赖百当－14－烯－13醇异构体和2种8，13外氧赖百当－14－烯－13－酮异构体，二氢猕猴桃内酯、茄酮和降茄二酮等成分在陈化过程中有明显的增加，总的香气物质含量变化的高峰期出现在陈化18~21个月。

The invention includes all sterioisomeric forms, including individual diastereoisomers and enantiomers of the compound of formula as well as racemic and non-racemic mixtures thereof.

本发明包括式化合物所有的立体异构形式，包括单个的非对映异构体和对映异构体，及其外消旋的和非外消旋的混合物。

Comparisons between the experimental and computational IR spectra clarify the difference of the open- and closed-ring isomers, which indicate that it is possible to identify the tautomeric form of this diarylethene derivative using a highly selective infrared absorption band and the strong absorption at 1 705 cm-1 of the ring-closed isomer can be used in non-destructive readout by IR light.

通过红外吸收光谱表征了该光致变色二芳基乙烯衍生物在溶液中开、关环前后结构的变化，并采用理论化学计算方法研究了该化合物开、关环异构体的红外吸收振动特性。光致变色异构化过程可以通过红外吸收光谱的变化而识别。关环异构体在1 705 cm

The combined acids , LHZZS,XDZZS and SLZZS, one of four fractions in montan resins from montan waxes from Liaohu, Xundian and Shulan brown coal respectively, were derived by CH 2N 2 to methyl esters and their chemical constituents and structural characteristic were studied on GC-MS.

结果显示，树脂结合酸均以正构烷酸为主要成份，其分布为C1 2 ～C2 8，高含量的正构烷酸集中在低碳数一端，C2 0 含量最高，其次为C1 6 ，而舒兰结合酸中，正构烷酸占绝对优势，且C1 6 为最高含量的化合物；去氢松香酸在每一个样品中含量较低，其它三环二萜酸，如松脂酸、三达松脂酸等异构体或立体异构体含量也非常低；具有五环三萜骨架的酸性物质，在潦浒、舒兰结合酸中比较丰富，其含量超过寻甸结合酸；在低碳数一端，存在着各种支链烷酸及苯甲酸、苯酚及取代物。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。