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汉语拼音：cuī huà jì

在化学反应中能降低反应物的活化能，使其他物质的反应速度加快，而本身的质量和组成都不改变的物质。如在化工生产中常用铁作催化剂来加快氨合成的速度。一般具有选择性。某些可抑制或延缓反应进行的物质，称抑制剂”，也曾称负催化剂”，如橡胶中加入抗氧剂以延缓老化。

1. 能加速或延缓化学反应速度，而本身的重量和性质并不改变的物质。旧称触媒。

• A catalyst is a substance which speeds up a chemical reaction.

  催化剂是一种能加速化学反应的物质.

• Various ceramic materials have been suggested as supports for reforming catalyst.

  各种陶土管用作转化催化剂的载体.

• To pass the water test the catalyst should not disintegrate or crumble.

  经过泡水试验,催化剂应不开裂或破碎.

• This process relies on a catalyst of high selectivity and week activity.

  这过程所靠的是一种高选择性和低活性的催化剂.

• Activated charcoal is known to be an excellent catalyst for many reactions.

  已知活性炭对很多反应是一种极好的催化剂.

• The catalyst is subjected to a uniform ram pressure.

  催化剂承受均匀活塞压力.

• Commercially two main types of hydrogenations are carried out with Nickel catalyst.

  商业上采用的以镍作催化剂的氢化有两种.

• For the catalyst producer, catalyst manufacturing cost and material limitations are paramount.

  对于催化剂制造厂来说, 催化剂生产成本和原料规格限定是最重要的.

• The reaction takes place only in the presence of a catalyst.

  只有在催化剂的作用下,反应才会发生.

• Many processes that are essential to the chemical industry use heterogeneous catalysts.

  很多重要的化学工业过程就是使用多相催化剂的.

• There is actually a failure of the integral particle of the catalyst.

  实际上存在有整粒催化剂的破碎.

• Catalysts that lower markedly the activation energy of the reactions are required.

  需要显著降低反应活化能的催化剂.

• Those catalysts are used in small tubular reactors.

  那些催化剂用于小型管式反应器.

• Each electrode is impregnated with a catalyst to speed the oxidation reduction or half reaction.

  每个电极掺入催化剂,以加重电池半氧化或还原反应.

• The effect of these catalysts is greater at low pressures than at high pressures.

  在低压下这些催化剂的作用要比在高压下为大.