缩短
- 与 缩短 相关的网络例句 [注:此内容来源于网络,仅供参考]
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This results in a shorter development timeframe – and who doesn't care about efficiency?
结果就是开发周期的缩短——谁会不关心效率呢?
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The invention relates to a process for producing polyethylene terephthalate 1, 3-propanediol, which comprises the following steps: using titanic acid ester as major catalyst, using germanium compounds and cobalt compounds as synergic catalyst, conducting esterification reaction for poly terephthalic acid and 1, 3-propanediol according to the molar 1:1.05-2.2 under the nitrogen pressure of 0.1-0.4MPa and 230-265 DEG C, or conducting ester exchanging reaction for poly terephthalic acid and 1, 3-propanediol according to the molar ratio 1:1.8-2.2 in 160-220 DEG C, decompressing reaction to high vacuum 10-150Pa, wherein the final temperature of reaction is 265-275 DEG C, recovering to normal pressure with nitrogen to obtain the PTT product.
本发明涉及一种生产聚对苯二甲酸1,3-丙二醇酯的方法,采用以钛酸酯为主催化剂,锗化合物和钴化合物为协同催化剂,对苯二甲酸二甲酯和1,3-丙二醇按摩尔1∶1.05-2.2,在0.1-0.4MPa氮气压力和230-265℃下进行酯化反应,或对苯二甲酸二甲酯和1,3-丙二醇按摩尔比1∶1.8-2.2,在160-220℃进行酯交换反应,将反应减压至高真空10-150Pa,反应终温在265-275℃,用氮气恢复到常压,得到本PTT产品;大大缩短了反应时间,直接聚合制备特性粘度在0.7-1.05dL/g的PTT切片,使反应产物色相良好,PTT产品可用于纤维加工及工程塑料领域。
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The invention relates to a preparation process for synthesizing polyethylene terephthalate 1, 3- terephthalate catalyst, which comprises adding titanic acid ester, germanium compounds and cobalt compound into liquid dispersed phase of organic solution, wherein the total weight concentration is 4-10%, and preparing the catalyst through mechanical stirring or ultrasonic wave mixed ligand for 10-60 minutes in 0-120 DEG C, wherein the adding content of titanic acid ester, germanium compounds and cobalt compound are respectively 200-500ppm, 50-300ppm and 100-400ppm of reaction monomer mass of terephthalic acid or dimethyl terephthalate.
本发明涉及一种合成聚对苯二甲酸1,3-丙二醇酯催化剂的制备方法,将钛酸酯、锗化合物和钴化合物加入到有机溶剂的液体分散相中,总重量浓度为4~10%,在0-120℃通过机械搅拌或超声波混配10-60min制得;钛酸酯、锗化合物和钴化合物加入量分别是对苯二甲酸或对苯二甲酸二甲酯反应单体质量的200-500ppm、50-300ppm、100-400ppm;用此催化剂制备PTT产品,酯化和缩聚反应时间相对于单独使用钛酸四丁酯缩短了30-60min,产品特性粘数0.70-1.05dL/g,色相b值在2-6之间,切片可用于加工新型合成纤维及工程塑料产品。
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Changed fast by a society and shortened knowledge half-life in the 21st century, in the face of such a society , make us to have to change one's own study way-individual learning turned to team learning.
二十一世纪是一个社会快速变迁,知识半衰期缩短的一个世纪,面对这样的社会,迫使我们不得不改变自己的学习方式-由个人学习转向团队学习。
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But to make a long story short, I'm Canadian.
先把故事缩短了说吧,我是加拿大人。
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In its transformation, the 370Z droptop gains a shortened windshield and standard automatically latching power top that takes about 20 seconds to fold under a body-colored steel tonneau.
在转变,取得了370Z droptop缩短挡风玻璃和标准自动闭锁权力顶端的约20秒,下一个机构褶皱彩色钢tonneau 。
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Methods In order to shortening operative time limitation of laminectomy was selected for exposing the L4-S1 posterior nerve roots,The percentage of roots to be sectioned depend upon the tonus preoperatively.
方法为缩短手术时间,术中行限局性腰骶部椎板切除,将显露在视野内的L4至S1脊神经前支切断。
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It has selected for using the total mark method with long step of turning into in emulation , and it is analyzed and starts with mechanism, carried on rational simplifying to the model , reduces the model calculate time , thus it improves the practicability of the model.
仿真中选用了变步长的积分方法,并从机理分析入手,对模型进行了合理的简化,使得模型计算时间大大缩短,从而提高了模型的实用性。
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Between 1985 and 1996, for example, America's freight railways dramatically reduced their employment , trackage, and their fleets of locomotives- while increasing the amount of cargo they hauled.
在1985年到1996年之间,美国铁路货运大幅度裁员,缩短了路径,减少了货运车辆但同时却增加了货运的总量。
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Rapid rate of heat transfer minimizes the time a product remains at elevated temperature.
快速的传热能缩短产品保持在高温下的时间。
- 推荐网络例句
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Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.
在对危险的南部地区访问时,他斥责什叶派民兵领导人对中央集权的挑衅行为。
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In fact,I've got him on the satellite mobile right now.
实际上 我们已接通卫星可视电话了
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The enrich the peopling of Deng Xiaoping of century great person thought, it is the main component in system of theory of Deng Xiaoping economy, it is a when our country economy builds basic task important facet.
世纪伟人邓小平的富民思想,是邓小平经济理论体系中的重要组成部分,是我国经济建设根本任务的一个重要方面。