评述了各种扩环催化剂的催化特点。
The catalytic specialities of ring enlarging catalysts were also discussed briefly.
方法以3-溴苯胺为起始原料，经过成环、氧化、扩环等反应得到目标产物。
METHODS Bretazenil was synthesized from 3-bromoaniline by cyclization, oxidation and ring-enlargement reaction, etc.
在乙腈溶剂中，碳酸钾存在下，双咪唑啉和1，2-二溴乙烷进行扩环反应，得到环状中间体一溴盐，产率78。
The reaction of bis-imidazoline with 1,2-dibromoethane and potassium carbonate in acetonitrile provided monobromide salt with a yield of 78.
而自由基扩环反应是合成中环乃至大环有机化合物的一种有效的新方法，已成为当今有机合成化学的前沿研究领域之一。
Radical ring expansion is a new strategy to synthesize the medium-sized and even large rings, nowadays, it is one of the important research fields of organic chemistry.
在扩眼体设一斜水眼，在导眼体与扩眼体之间连接一缩径增效排屑环，强化了冷却清洗作用，从而保证钻头有较好的使用效果。
Set up a slant water hole at reamer, and connect the reamer and pilot with reducing synergy flute, which strengthen the cooling and washing function and ensure the bit's effects.
实践证明，扩冲法修复护环简单、经济、实用。
The practical experience shows that the expanding method is very easy, economical and practical for the operation.
导向辊的控制在环件辗扩中有着重要意义。
The controlling of guide roller in ring rolling is very important.
冷辗扩是一种生产高精度、高性能无缝环的技术，其过程具有很强的非线性。
Cold ring rolling is a technology to produce high precision and performance seamless ring and its process has strong nonlinear.
BMI与二元胺扩链后，再与液晶环氧(PHBHQ)共聚，可以有效地提高BMI树脂的冲击强度。
The impact strength of BMI can be improved remarkably by copolymerizing with liquid crystalline epoxy (PHBHQ) after extending chain.
这些现象的本质是环件冷辗扩过程中的径向和轴向塑性区的分布不同。
The nature reason of these phenomena was that the radial and axial plastic zone distributions were different in cold ring rolling.
详细介绍了用扩冲法对液压胀形出现凹形的护环进行修复的方法。
This article has described expanding method for repairing the concave retaining ring caused by the hydraulic bulging.
本文扼要介绍了护环液压扩胀时产生形状缺陷的原因及校正的原理与方法。
Reasons of causing shape defects of the retaining ring by hydraulic expanding and principles and methods of sizing the shape are briefly presented.
根据环件辗扩实验结果，对文中的辗扩力和力矩计算公式进行了验证。
The formulae of roll force and torque are verified by ring rolling experiment.
采用一步法合成以4 ，4 '-甲烷二环已基二异氰酸酯（HMDI）、扩链剂1，4 -丁二醇（BDO）为硬段，聚四氢呋喃醚（PTMG）为软段的脂肪族聚氨酯。
The one step method was adopted in this study to synthesize aliphatic polyurethane with 4,4 methylene dicyclohexyl diisocyanate(HMDI), 1,4 butanediol(BDO) and poly (tetrahydrofuran)(PTMG).
在低速环形叶栅实验台上圆弧斜槽处理轮毂相对静子扩压叶栅环的旋转频率对叶栅端壁区流动进行了影响实验探索。
An experiment was made in an annual cascade to explore the unsteady flow mechanism of skewed slot hub treatment in removing flow separation near hub.
目前，冷辗扩技术生产简单截面的环件很成功，但是生产异性截面的环件还存在较多的问题，例如生产锥形套圈由于变形不均匀会产生许多问题。
Now, this technology is very successful in rolling simple rings, but there are many problems in rolling complex rings which have not symmetry section shape.
冷辗扩是生产高质量无缝环件的新工艺，圆锥套圈辗扩由于金属分布的不均匀导致辗扩过程会产生较大轴向力，同时端面出现拉凹。
Cold ring rolling is a new technology to produce high-tech seamless rings. The asymmetry of the metal distribution in the taper ring causes large axial force, as well as sunken side faces.
环空管道后台阶突扩流动是空气正循环钻井过程中十分重要的关键部分，直接决定了钻探岩屑是否能够顺利上返地面。
The flow over a backward facing step of an annular tube is a very important part of air drilling, determining the detritus going back to the ground successfully.
基于ABAQUS对冷辗扩过程进行了数值模拟，并在D50G91轧环机上轧制出了质量较好的环件成品。
The ring rolling simulation was analyzed based on ABAQUS. And then the qualified products were produced by D50G91 roller.
结论：选择适当的培养基及培养方法摇瓶扩繁蜜环菌后代，再进行选择培养是复壮蜜环菌菌种最简易的方法。
Conclusion: It was the easiest way to rejuvenate A. mellea strain by multiplying the clonal offsprings in a proper medium, together w…
结论：选择适当的培养基及培养方法摇瓶扩繁蜜环菌后代，再进行选择培养是复壮蜜环菌菌种最简易的方法。
Conclusion: It was the easiest way to rejuvenate A. mellea strain by multiplying the clonal offsprings in a proper medium, together w…
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