异构体

The crude oils of Chang 20 belong to typical immature oil which have odd even predominance and lower ratios of sterane and terpane maturity index.

长20井的原油既具有正烷烃奇偶优势，又具有较低甾萜烷异构体比值，属于典型的低熟原油。

Structural analysis reveals that the assemblies of these complexes are mainly directed by counter anions, followed with the change of anions from simple inorganic species (SCN~-/dca/Cl~-) to organic ones (ip/nip/tp/chdc), diversiform structures are formed varying from mononuclear, tetranuclear molecules to infinite 1-D and 2-D frameworks.

第三章利用4-bpt的同分异构体4-氨基-3，5-双(2-吡啶基)-1，2，4-三唑(2-bpt)作为螯合试剂，与多种无机/有机阴离子以及金属Cd~盐反应，得到了一系列Cd~配位化合物(7-15)。

Density functional method was applied to the study of the isomers of the primary explosive of tetrazene.

采用密度泛函理论对四氮烯起爆药的异构体进行研究。

The geometrical structures of the three isomers of tetrazene molecule which had been proposed formerly were fully optimized at the B3LYP/6-311 +G(superscript **) level of theory.

在B3LYP/6-311+G水平下对四氮烯三种异构体分子的几何结构进行全优化计算。

Comparisons show that there is no correlation between the experimental sensitivity of tetrazole compounds and various previously proposed theoretical static criteria, such as the bond length and bond order of relevant bonds, net atomic charges and electronegativity and the content of 2H-teterazole isomers in both gaseous and condensed states.

把四唑衍生物的实验感度与前人曾提出过的各种感度理论判据—一些静态结构性质(如相关键的键长、键级、原子电荷和电负性等)以及平衡体系中2H-异构体的含量—进行比较，均未找到它们之间的规律性联系。

Following resolution, the following steps are performed: reduce the isomer to an alcohol, react the alcohol with triphenylmethyl chloride, ozonalyze the resulting reaction product, reduce the ozonalyzed product to yield a diol and react the diol with a methane sulfonyl compound to form-3-2-{(methylsulfonyloxy}ethoxy-4--1-butanol methane sulfonate.

拆分后，进行下一步：将异构体还原为醇，使醇与三苯基甲基氯反应，臭氧化所得反应产物，还原臭氧化产物以得到一种二醇并使所述二醇与甲烷磺酰基化合物反应以形成-3-2-{(甲基磺酰基氧}乙氧基-4--1-丁醇甲烷磺酸酯。

At 60 ℃ the reaction of 1-O-alkyl-2-O-acetyl-3-O-trityl glycerol with iodine/methanol system removed trityl and acetyl and gave 1-alkyl glycerol. But at r.t. the reaction only removed trityl and gave two isomers 1-O-alkyl-2-O-acetyl glycerol and 1-O-alkyl-3-O-acetyl glycerol.

1-烷氧基-2乙酰氧基-3-三苯甲氧基甘油醚与碘/甲醇体系反应，在60 ℃时，同时发生了脱三苯甲基及乙酰基，在室温下，仅脱三苯甲基，但乙酰基在反应过程中发生了部分转移，产生了两个异构体。

We report a previously uncharacterized alpha-helical module, the BEN domain, in diverse animal proteins such as BANP/SMAR1, NAC1 and the Drosophila mod(mdg4) isoform C, in the chordopoxvirus virosomal protein E5R and in several proteins of polydnaviruses.

我们在多种动物蛋白质，如BANP/SMAR1，NAC1和果蝇mod(mdg4)异构体C，及脊椎动物痘病毒亚科蛋白质E5R和一些多去氧核糖核酸病毒科中，报道了一个以前没有描述的α螺旋结构模块----BEN结构域。

The twenty three N-acylalanines which have unsimilar structures and different stereoisomers were used for general, preliminary and second screening tests of fungicidal activities for above four fungi.

最终获得的23种具有不同结构，不同旋光异构体的化合物，再以上述四种致病菌为防治对象，进行了杀菌活性的普筛、初筛和复筛试验。

The results showed that the addition leading to -2-phenyl-2-(2-vinylpiperidin-1-yl) ethanol 7 could proceed with good diastereoselectivity and excellent yield (95%).(3) The selective N-deprotection of -2-phenyl-2-(2-vinylpiperidin-1-yl) ethanol 2 without affecting the vinyl group in the substrate were untaken.(4) The Zip reaction for the transformation of -1-(3-aminopropyl)-3-methylazecan-2-one 8 to -7-Methyl-1, Sdiaza-cyclotetradecan-6-one 9 were undertaken. The results showed that, under controlled conditions, acceptable yields (43%) could be achieved and racemization can be minimized during the ring expansion reaction.

该合成路线与文献方法相比，反应条件较温和，也缩短了反应时间；(2)哌啶衍生物2与乙烯基格氏试剂进行加成反应的条件和立体选择性，取得了较好的结果（差向异构体比为80：20，产率95％左右）；(3)不饱和哌啶衍生物7在不影响碳碳双键的情况下去除苯基甘氨醇手性辅助基的条件；(4)具有羰基α位手性的氨基酰胺8在不同条件下经Zip重排反应转变为9的反应，控制反应条件，可使反应中消旋化减小到最小的程度。

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。