胆甾烷

Whenpyridine was used as reductive decomposing agent, the expecting cholest-4-en-3,6-dione-22-al was obtained. However, when Zn/HOAc was used to decomposethe ozonide, C-4,5 double bond was further reduced to give cholest-3,6-dione-22-al as main product. 2 For the side-chain construction of compound (1), the solid-liquid phase-transfer Wittig reaction was used. When (3-methyl-2-oxobutyl)-triphenylarsonium bromide was used as reagent, the reaction can be carried out inmild reaction condition and the yield is higher than that when phosphorane wasused.

但使用Zn／HOAc作为分解剂时，却得到其氢化产物胆甾-3， 6-二酮-22-醛；2在甾体支链引入过程中，采用固-液相转移Wittig反应的方法，用(3-甲基)-2-氧丁基三苯基溴化胂作为试剂，反应在非常温和的条件下便可完成，而且产率比传统采用膦烷的方法更高；3在对某些甾酮化合物的选择性还原反应研究时，发现在〓还原体系中，当加入某些金属离子后，反应有更好的区域选择性和立体选择性。

Three days after inoculation, 67.13% grape phylloxera selected 'Kyoho', while only 15.29% and 17.58% phylloxera selected '5BB' and '140Ru', respectively.

对砧木5BB和巨峰根系的挥发性组分进行测定，发现2个品种挥发物独有组分数量均较高，巨峰独有组分为23个，占总成分数的48.94%，5BB的独有组分为32个，占总成分数的57.14%。5BB和巨峰的共有组分为24个，主要成分均为亚油酸甲酯和反油酸甲酯，但含量有所不同，其中，5BB以倍半萜类的丁香醇及脂肪酸甲酯类的亚油酸甲酯，反油酸甲酯，棕榈油酸甲酯含量较高，高于巨峰中相应物质含量的4.23%~6.46%，而巨峰以邻苯二甲酸二丁酯及胆甾烷含量较高，分别高于5BB相应组分含量的6.81%和1.07%。

Two pathways of cleavage and conversion in ring B of ergostane and cholestane are summarized.

第二部分总结了麦角甾烷及胆甾烷B环裂解和转化的两种途径。

The results showed that the copolysiloxanes behaved liquid crystal phase in a certain range of cholesteryl content.

结果表明：这类共聚硅氧烷在一定的胆甾基含量范围呈现液晶相，由于长链烷酯基的引入，液晶相转变温度降低。

We use this technology to measure some rock and oil sample taken from Liaohe or Tarim basin. We identified many series of biomarker with dividing-era significance. These series are C26 steranes, C30 methylsteranes; and methly hopanoid alkanes, hexacyclic hopanoid alkanes, which two series were measured first by our laboratory in China.

本论文建立地球化学样品GOMS／MS分析方法；并对辽河盆地和塔里木盆地岩石及原油样品进行GC／MS／MS分析，鉴定出多个系列具有划时代意义的生标组分，这些组分是用GC／MS技术无法检测的极微量的生标组分：C26降胆甾烷系列、C30甲基甾烷系列等：还有高碳数甲基藿烷系列和六环藿烷系列见图1，图2，在国内被我们实验室首次检出。

By means of GC-MS-Ms method, the multiple series of age-related and taxon specific biomarkers are tested in source rocks and oil samples from Liaohe oilfield and Tarim basin, which are hard to be detected by conventional GC-MS method. They are steranes, methylsteranes, Tricyclic and tetracyclic diterpanes, methyl hopanoid alkanes and hexacyclic hopanoid alkanes, etc.

利用色谱－质普－质普方法在辽河与塔里木盆地源岩和原油样品中，检测出了多个系列时代相关及特定种属生物标志物，包括：降胆甾烷系列、甲基甾烷及甲藻甾烷系列、三环二萜烷及四环二萜烷系列、六环蒮烷及甲基藿烷系列等等，这些化合物很难用常规GC-MS形方法检测到。

Comparing with marine oils in the adjacent areas, all crude oils in Hade 4 oil field (except for HD401 well) have following peculiarity: very similar in the composition of light hydrocarbon fraction, and the distribution of of phytane-series isoprenoid alkanes, high concentration in steranes, terpanes and their aromatized compounds, as well as rearranged steranes; low concentration of gammacerane, 24-norcholestanes and 24-rearranged steranes, and low C〓 regular steranes C〓/(C〓+C〓+C〓＜20%; 3-methyl steranes and 27-norcholestane predominated, respectively; very low concentration of dinosterane and 4-methyl steroid.

分析表明，与相邻地区海相原油比较，除最南端的HD401井原油外，其它井区原油均具有下述特点：轻烃馏分组成十分接近、植烷系列类异戊烯烷烃分布较为一致、甾萜类和芳香甾萜类环状化合物浓度较高、重排甾烷丰度较高、伽马蜡烷含量低、规则甾烷组成中C〓丰度低C〓/(C〓+C〓+C〓＜20％、甲基甾烷中以3-甲基甾烷为主、甲藻甾烷和4-甲基甾烷丰度极低、降胆甾烷中以27-降胆甾烷为主、24-降胆甾烷和24-重排降胆甾烷丰度低。

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。