助手标题  
全文文献 工具书 数字 学术定义 翻译助手 学术趋势 更多
查询帮助
意见反馈
   rapid 在 化学 分类中 的翻译结果: 查询用时:0.146秒
图标索引 在分类学科中查询
所有学科
化学
园艺
地球物理学
石油天然气工业
公路与水路运输
轻工业手工业
环境科学与资源利用
地质学
计算机软件及计算机应用
更多类别查询

图标索引 历史查询
 

rapid
    很抱歉,暂未找到该词条在当前类别下的译词。您可以查看在所有学科下的译词。
相关语句
  “rapid”译为未确定词的双语例句
    Study on Precipitation of Supported Metallocene Catalyst Microparticles by Rapid Expansion of Supercritical Solutions
    超临界溶液共沉析制备负载型茂金属催化剂微粒的研究
短句来源
    Simple and Rapid Simultaneous Determination of Micro Amount of Zinc,Lead and Copper in Human Hair by Polarographic Adsorptive Compiex Waves and the Evaluation of thhe Determination Results
    极谱配合吸附波法同时测定人发锌、铅、铜与评价
短句来源
    Rapid Determination of Fe, Pb, Mo and Sn in 703 Friction Material by AAS
    703摩擦材料中Fe、Pb、Sn、Mo的原子吸收光谱测定
短句来源
    RAPID ULTRAVIOLET SPECTROPHOTOMETRIC DETERMINATION OF NITRATE IN WATER
    紫外线吸光光度法测定水中硝酸盐
短句来源
    THE USE OF MICROWAVE OVENS AND ORGANOTELLURIUM OXIDE FOR CATALYTIC RAPID SYNTHESIS OF α,β-UNSATURATED
    微波辐射下有机碲氧化物催化合成α,β-不饱和酮
短句来源
更多       
查询“rapid”译词为用户自定义的双语例句

    我想查看译文中含有:的双语例句
例句
为了更好的帮助您理解掌握查询词或其译词在地道英语中的实际用法,我们为您准备了出自英文原文的大量英语例句,供您参考。
  rapid
The use of time-frequency methods (phase space methods) allows the use of rough symbols of ultra-rapid growth in place of smooth symbols in the standard classes.
      
The pharmaceutical sciences are advancing rapidly in the post-genomic era of the 21st century with the completion of the human genome, as well as those of many other organisms including bacteria and parasites, and the rapid advances in proteomics.
      
The α-isomer exhibited rapid and significantly higher peak plasma concentrations in all the species post intramuscular administrations, while β-isomer showed prolonged plasma levels.
      
This suggests that the rapid initial reduction in percent parasitemia may be due to α- isomer and the activity is maintained by the β- isomer.
      
Flavonoid antioxidants act as scavengers of free radicals by rapid donation of a hydrogen atom.
      
更多          


In view of the necessity of a rapid and accurate process for the deter-mination of fluorine applicable in the analysis of sodium fluoride and otherfluorine compounds,the author has established a new volumetric processconsisting in the titration in aqueous-alcoholic medium with ferric nitrate asstandard solution and sodium salicylate as indicator.All of the methods,published by Guyot,Greeff,Fairchild andVisintin proposed for the determination of fluorine using ferric solutionas standard,are based on the...

In view of the necessity of a rapid and accurate process for the deter-mination of fluorine applicable in the analysis of sodium fluoride and otherfluorine compounds,the author has established a new volumetric processconsisting in the titration in aqueous-alcoholic medium with ferric nitrate asstandard solution and sodium salicylate as indicator.All of the methods,published by Guyot,Greeff,Fairchild andVisintin proposed for the determination of fluorine using ferric solutionas standard,are based on the reaction:6NaF+FeCl_3→Na_3FeF_6+3NaCl. But the sodium ferric fluoride thus formed is fairly soluble in water and makesthe end-point unclear,therefore the titration can not be performed accurately.This seems to be due to the fact that the following two reactions advancesimultaneously,and accordingly the formation of sodium ferric fluoride is in-complete in aque(?)us medium:3NaF+Fe(NO_3)_3→FeF_3+3N_aNO_33NaF+FeF_3→Na_3FeF_6Nevertheless,these reactions,according to the author's experiments;proceedalmost quantitatively in meda.containing at least 50% by volume of alcohol.This paper reports the xperimental results obtained in the fundamentalstudies on the various factors influencing the accuracy of the volumetry,namely,the sensitivity and the necessary amount of sodium salicylate used asindicator,the pH value,the alcoholic concentration of the titration medium,the concentration of the fluoride taken for the determination and the timewhen alcohol should be added in the course of titration.Furthermore,a rapidvolumetric process with high accuracy is proposed together with its applicationsin ordinary analyses of sodium fluoride and other fluorine compounds.The proposed method is characteristic in using sodium salicylate asindicator,which shows sharp violet color with minute amount of ferric ion inmedium of pH 3 controlled with buffer solution,then titrating with standardferric nitrate,and adding proper amount of alcohol(the alcoholic concentra-tion at the end-point should be above 50%)during the titration,when themedium becomes orange yellow in color.The method may be summarized as follows:Take 5 ml of neutral sodiumfluoride solution of about 0.3 N in a small Erlenmeyer flask,add 2.5 mlof Walpole's buffer solution of pH 3(formed by dissolving 34.0 g ofcrystalline sodium acetate and 20 ml of 38% HCl in water,and making upto 250 ml)and 1 ml of 0.1 M sodium salicylate dissolved in 50% alcohol.After sufficient stirring,titrate with standard 0.3 N(0.05 M)ferric nitratesolution,using micro-burette until the medium becomes orange yellow,thisstep being reached after addition of about 4 ml of titrant.Then decolorizethe solution by adding 12.5 ml of absolute alcohol(or 13 ml of 95% alcohol),previously purified by redistillation with lime;stirring is necessary during theaddition.Further continue the titration until the light pink color formeddoes not fade after stirring for 30 seconds when observed over a white surface. In the analyses of sodium fluoride and other fluorine compounds con-taining interfering substances,such as divalent and polyvalent metallic ions,phosphate,silicate,borate,carbonate,sulfide ions and reductants acting on ferricion,it is necessary to separate fluorine from these interfering substances bythe distillation with sulfuric acid according to the method of Willard andWinter(20).Then the distillate is neutralized with dilute sodium hydroxideand adjusted to the proper pH with hydrochloric acid using p-nitrophenol asindicator.The solution is ready for titration as described.But in the caseof absence of these interfering substances except carbonate,for example,inthe determination of the concentration of sodium fluorde solution obtained bythe extraction of the crude product,produced industrially by fusing fluorsparwith sodium carbonate and silica,the above separation of fluorine by dis-tillation is dispensable.The anaIytical results obtained by the proposed method are in goodagreement with those obtained by the lead chlorofluoride process(8),whichis recognized as official method for the determination of fluorine in agriculturalproducts.

本文介绍一容量分析氟的新方法和在工业制品上的应用,并分析了一种工业制备的氟化钠液,所得的结果和氟氯化铅法所得的极为一致。对于影响该分析法准确度的各种因素:指示剂的灵敏度和滴定时适宜的用量、溶液的 pH 值、应加的乙醇量、操作中加乙醇的次序、以及氟离子的适宜浓度,均加以研究并找出适宜的情况。本法用硝酸铁为标准液,水杨酸钠作指示剂,在 pH=3左右作滴定;当溶液呈橙黄色时,加入适量的乙醇,使其浓度在终点时仍不低于50%。如有干扰物质如二价及多价金属离子、磷酸根、矽酸根、硼酸根、碳酸根、硫化物和还原物质可能与三价铁起作用者,均应分离之。

A modified method bassd on the Terent'ev method of "active hydrogen" determination has been developed, by means of which both "active hydrogen" and CH3MgI addition can be determined.In this paper the procedure of the method was described in detail and a few examples of determination were given.In comparison with Kohler's method, though this method appears to be less satisfactory in accuracy, it has the advantage that the apparatus is simpler to construct and the determination easier and more rapid to be...

A modified method bassd on the Terent'ev method of "active hydrogen" determination has been developed, by means of which both "active hydrogen" and CH3MgI addition can be determined.In this paper the procedure of the method was described in detail and a few examples of determination were given.In comparison with Kohler's method, though this method appears to be less satisfactory in accuracy, it has the advantage that the apparatus is simpler to construct and the determination easier and more rapid to be carried out.

作者根据测定活泼氢的方法,在仪器及操作程序上加以改进,使这个方法能够同时用来测定CH_3MgI试剂的加成。本文详细地描述了这一改进方法并且给出几个测定的结果。与Kohler方法相较,这个方法虽然准确度稍差一些,但所用玻璃仪器易於吹制,操作程序也比较简便。

The influence of 6-aminocaproic acid on the polymerization of caprolactam has been studied.Samples of five sets of different mole ratios of the catalyst and caprolactam were sealed inseparate tubes and heated at 230±1° in a specially designed tube furnace.They were takenout at various time intervals and analyzed for the contents of monomer,cyclic oligomer andhigh polymer.The average molecular weights of the polymer were also determined.Experimental results showed that the formation of the polymer and the consumption...

The influence of 6-aminocaproic acid on the polymerization of caprolactam has been studied.Samples of five sets of different mole ratios of the catalyst and caprolactam were sealed inseparate tubes and heated at 230±1° in a specially designed tube furnace.They were takenout at various time intervals and analyzed for the contents of monomer,cyclic oligomer andhigh polymer.The average molecular weights of the polymer were also determined.Experimental results showed that the formation of the polymer and the consumption ofthe monomer were both rapid at the beginning of the reaction,then became slow,and finallyapproached a definite proportion.The contents of the cyclic oligomer remained nearly constantthroughout of the reaction course.The ratio of the polymer,monomer and cyclic oligomerapproached a definite value in all five sets of experiments.The number average molecularweights of the polymer raised also rapidly at the beginning,and became gradually slow duringthe course of the reaction.The molecular weights of the sets using smaller quantifies of catalystexceeded,after a certain time interval,those of the sets using larger quantities of the catalyst.At the final stage,the molecular weights of the different sets all approached to their appropriatevalues.It was suggested,in view of these results,that 6-aminocaproic acid acted as the center ofgrowing chain and at the same time as an initiator which induced the formation of new chainsfrom caprolactam.During the course of the reaction,addition polymerization,polycondensa-tion,chain splitting and chain interchange occurred concurrently.Addition polymerizationdominated at the earlier stage,and the polycondensation between macromolecules followed.Thesystem of ultimate equillibrium between monomer,cyclic oligomer,high polymer and waterwas finally established by chain splitting and chain interchange.

6-氨基己酸对已内醯胺聚合反应的影响曾进行了研究。分别以五种不同量的6-氨基己酸为催化剂于230±1°在封管中进行己内醯胺的聚合。测定其各组试样在各反应时间后所得聚合产物中的单体含量,低聚体含量和聚合体生成量,以及聚合体的数均分子量。实验结果显示,单体含量随反应时间而迅速减少,聚合体生成量则迅速增加,均随催化剂用量而有不同的速度。最后各组之单体含量及聚合体生成量均分别趋于一定的数值。低聚体在各反应时间内均大致保持一定的量。各组聚合体的数均分子量,开始时以催化剂用量最多者上升最快,催化剂用量较少者经若干时间以后逐渐超过催化剂用量较多者。最后,各组的数均分子量均各自分别达到一定的数值。我们推论,6-氨基己酸对己内醯胺具有引发和生链的作用,而各级聚合体亦有同样作用。在反应过程中,加聚、缩聚、降解和交换等反应均同时存在,在起始时以加聚为显著,伴之而起的即有大分子间的缩聚,最后通过链的降解和链的交换连到单体、圜型低聚体和各级聚合体与水之间的一个总平衡体系。

 
<< 更多相关文摘    
图标索引 相关查询

 


 
CNKI小工具
在英文学术搜索中查有关rapid的内容
在知识搜索中查有关rapid的内容
在数字搜索中查有关rapid的内容
在概念知识元中查有关rapid的内容
在学术趋势中查有关rapid的内容
 
 

CNKI主页设CNKI翻译助手为主页 | 收藏CNKI翻译助手 | 广告服务 | 英文学术搜索
版权图标  2008 CNKI-中国知网
京ICP证040431号 互联网出版许可证 新出网证(京)字008号
北京市公安局海淀分局 备案号:110 1081725
版权图标 2008中国知网(cnki) 中国学术期刊(光盘版)电子杂志社