丙烷

Chiral ligands mentioned above and their complexes with acetate copper were used as enantio-selective catalysts in asymmetric cyclopropanation reactions of diazoacetate and 1,1-diphenyl ethylene. Investigations indicate that all of them reveal certain optical-selective capability, but chiral C2-symmetric 2,6-bispyridine ligands show better catalytic capability than chiral asymmetric schifF-base ligands.

选择了2个手性2，6-吡啶双噁唑啉配体和6个手性不对称席夫碱配体与醋酸铜形成的配合物作为催化剂，对重氮乙酸乙酯与1，1-二苯乙烯不对称环加成进行催化反应，发现这8个催化剂对1，1-二苯乙烯的不对称环丙烷化反应都表现出了一定的光学活性诱导能力，手性2，6-吡啶双噁唑啉-铜类具有比手性Schiff碱-铜类更好的催化性能。

The death radius by blast fireballs is smaller than that by blast wave, the 2nd burn radius is smaller than the 50% eardrum rupture radius, and the 1st burn radius is smaller than the 1% eardrum rupture radius, if the amount of gas fuel which contributes to vapour cloud explosions is less than 1×10〓kg propane.

10药量小于1×10〓kg丙烷时，蒸气云爆炸火球热辐射致死半径小于冲击波作用下头部撞击致死半径；二度烧伤半径小于50％耳鼓膜破裂半径；一度烧伤半径小于1％耳鼓膜破裂半径；1％耳鼓膜破裂半径小于建筑物破坏得不能居住半径。

The adsorbability, adsorption kinetics and adsorption thermodynamics to acid green 6B, direct fast yellow RL and disperse blue 56 by the new resin were studied in this paper.

用本实验制备的甲醛环氧氯丙烷交联壳聚糖树脂对酸性绿6B、直接耐晒黄RL、分散蓝56三种染料进行吸附性能、吸附动力学和热力学研究。

Wedgeplug O-Seal plug valves with their positive, no-leak features are not only recommended as the best general purpose valves for handling hydrocarbons, vegetable oils, solvents, etc., but are ideal for such tough service as butane, propane, butadiene, acetone, ethyl alcohol, ammonia, anhydrous ammonia, benzene, vinyl chloride, dry chlorine, Dowtherm, ethane, ethylene, hydrogen chloride, napthalene, oxygen, hydrogen, phthalic anhydride, dry phosgene, phosphoric acid, potassium carbonate, styrene, molten sulphur, sulphur dichloride and related services within a temperature range from -300oF to + 450oF within pressure limits of the valves.

楔塞O形密封旋塞阀具有积极的、无泄漏特性，不但是最好的通用的阀门，用于处理碳化氢，植物油，溶剂等，还特别适用于严酷的应用环境，如丁烷，丙烷，丁二烯，丙酮，乙醇，氨，无水氨，苯，氯乙烯，干氯，道氏热载体，乙烷，乙烯，氯化氢，萘，氧，氢，邻苯二甲酸酐，干碳酰氯，磷酸，碳酸钾，苯乙烯，融化硫，二氯化硫，以及温度在-184oC至232oC之间，压力在阀门额定压力等级范围内的有关应用。

This catalyst system was applied in the cyclopropanation of other alkenes, and the results indicated that the catalyst system excelled mono-catalyst.

将这个催化体系用于其他烯烃的环丙烷化，结果表明，协同催化效果优于单一催化体系。

In this thesis, a series of uliphatic polyester anhydrides 〓COCH〓CH〓COO 〓OCOCH〓CH〓COO〓 and copolyanhydrides with 1, 3-bis (4-carboxylphenyloxy) propane were prepared.

本文中合成了一系列脂肪族聚酯酸酐〓以及与1，3-双（4-羧基苯氧基）丙烷的共聚物，研究了它们的降解性能和药物释放性能。

Different bottlers of fuel propane use different odourants and so do green gas bottlers hence the different smells.

不同的燃料丙烷使用的刺激性气体的添加剂都不同，所以绿气的味道也许是不同的。

Propylene epoxidation to propylene epoxide is one of the most important challenges in catalysis because this reaction possesses both industrial significance and academic importance.

中文摘要：丙烯环氧化制环氧丙烷具有重大的工业应用背景和重要的学术意义，开拓该反应的高效催化体系和催化剂是催化领域的最重要的挑战之一。

Technical grade propylene(92-93 percent,the balance being propane ) and anhydrous fertilizer grade ammonia are satisfactory.

技术级的丙烯（92－93％，平衡剂为丙烷）和无水化肥级氨水就能满足要求。

Study on the interaction between rarefaction wave and premixed propane-air flame In the research, the co-flow and counter-flow rarefaction wave were induced to intervene in the flame by different ignition scheme.

另外，管道中压力波的作用是Tulip火焰结构形成的重要原因。(2)研究了稀疏波对丙烷-空气预混火焰传播特性的影响。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷