环烷

According to the helix theory , the algebraic sum value of all rotations of dihedral angle helix is equal to zero in the structure of 1,3-disubstituted cyclohexane derivatives.

按照螺旋理论，1，3-二取代环已烷衍生物的结构中存在的二面角螺旋旋光度代数和为零，不应具有旋光性，但是它们却是光学活性的。

Already alkane and phenol has been important consumption fields of benzene in the ring.

环已烷和苯酚也是苯重要消费领域。二者各占苯消费量的15%-18%。

The running length of alkane distillation column was prolonged from average 2 months to more than 9 months.

环己酮生产工艺中烷蒸馏塔工作周期由改造前的平均2个月延长至9个月以上，实现整套装置长周期稳定运转。

One of them can efficient catalysed the alkene in the absence of dear additives by introducing an imidazole in the salen ligand.

其中分子内含咪唑的手性吡咯烷Mn催化剂成功实现了不加昂贵添加剂的情况下高效催化取代色烯环氧化反应。

Benzene undergoes metabolic oxidation by cytochrome P450 enzymes to form an electrophilic epoxide which can alkylate protein and DNA.

苯在细胞色素P450酶氧化代谢下，形成一种能烷化蛋白质和DNA的电环氧化物。

ResultsThe IC50 of the ethyl acetate extract from Alocasia macrorrhiza to A549, B16, BGC-823 were 94.6, 541.9,629.5 μg·ml-1 respectively,and those of the acetone extract from Alocasia macrorrhiza to A549 and B16 40.9,438.0 μg·ml-1 respectively. But there were quite large dosages of the IC50 of the extracts of cyclohexane, benzine, ethyl alcohol and water from Alocasia macrorrhiza to all kinds of cell lines.

结果海芋醋酸乙酯提取物对A549，B16，BGC-823的IC50分别为94.6， 541.9，629.5 μg·ml-1，丙酮提取物对A549，B16的IC50分别为40.9，438.0 μg·ml-1，而海芋的环己烷，石油醚，乙醇，水提物对各种细胞株的IC50剂量都比较大。

Objective To determine the risk of sustained amenorrhea in premenopausal women with systemic lupus erythematosus receiving intermittent pulse cyclophosphamide therapy.

环磷酰胺是临床最常应用的烷化剂，在对由免疫介导的风湿病、肾病、神经系统疾病及血液病等疾病的治疗中，疗效肯定。

The preparation of anisaldehyde by ozonolysis reaction from anethole was studied.

以茴香脑为原料，乙酸和环己烷的混合物做溶剂，臭氧化法制备茴香醛。

Based on the bioisosterism of malonate group with phosphate group, a series of barbiturate compounds and pyrazolidine-3, 5-dione compounds were designed and synthesized.

基于丙二酸是磷酸的生物电子等排体，我们设计了丙二酸的闭环结构的巴比妥酸及3，5-吡唑烷二酮类化合物。

In this paper,the detailed preparation process of gas chromatographic column for separating benzene series was introduced,the optimum column temperature and flow rate of carried gas were selected for separation the mixture of cyclohexane,benzene and toluene,and the column performance has been studied in respects to column efficiency and separating size.

本文主要介绍了气相色谱柱的详细制备过程，并以环已烷、苯和甲苯的混合物的分离为例，选择了最佳的操作条件。同时从柱效率和分离度两方面考察了该色谱柱的柱性能。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失