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
   coordinating group 的翻译结果: 查询用时:0.008秒
图标索引 在分类学科中查询
所有学科
矿业工程
更多类别查询

图标索引 历史查询
 

coordinating group
相关语句
  协作组
     Methods: By adopting the randomized controlled method, the clinical efficacy of treatment of patients with SARS, hospitalized from April 10,2003 to May 20, 2003 in Ditan Hospital, Beijing weas evaluated. All the patients were treated by western medicine according to the therapeutic program recommended by the SARS Coordinating Group, the Chinese decoction for clearing Heat and removing Dampness was given additionally to the 35 patients in the treated group, but it was not given to the 30 patients in the control group.
     方法:采用随机对照,对我院2003年4月10日—5月20日住院的SARS患者在实施SARS协作组推荐西医治疗方案基础上,治疗组(35例)加用清热化湿类为主中药水煎剂,并与单用西医治疗的30例作对照,分析两组临床疗效。
短句来源
  “coordinating group”译为未确定词的双语例句
     Speech at the Meeting of Inter-Ministries Coordinating Group about National Basic Research Program during the 11~(th) Five Year Plan
     在“十一五”全国基础研究规划部际协调领导小组会议上的讲话
短句来源
     The improved DEC synthesisperformance was attributed to the existence of CO as coordinating group for PdO andKCl effect by the reaction mechanism analysis.
     探讨了CO作为PdO的羰基配位体,在Schottky缺陷和空穴带的共同作用下的反应机理,以及催化剂中Cu-Pd间氧化还原的循环过程。
短句来源
     Because cooperative learning which is carried out in groups has its specific feature different from traditional teaching, some aspects such as class' management and organization, coordinating group activities, dealing with relationships among class, group and students, play important part in cooperative learning. This paper also goes further into the problem of teachers' role.
     由于合作学习课堂具有以小组学习的顺利进行来达成教学目标这一有别于传统教学的特点,因此对课堂的组织与管理,协调各个小组的学习活动,处理好全班—小组—学生个体之间的关系就显得尤为重要,为此本文还对合作学习小组组织冲突的协调及教师的角色问题作了进一步的探讨。
短句来源
     The separation effect (α)increased with the increase in the basicity of the coordinating group.
     α随配位基的碱性增大而相应提高。
短句来源
     Methods We made clinical analyses and tested the drug resistance to 18 kinds of antibiotics in 28554 cases of discharged patients from 1993 to 1995,accordirg to the standards fomulated by the nosocomial infections monitoring and coordinating group of Ministry of Health.
     方法参照卫生部医政司院内感染监控协调小组确定的标准,对1993~1995年中28554例出院患者发生院内感染1490例进行临床分析和对18种抗生素的耐药谱测定。
短句来源
更多       
  相似匹配句对
     The P&T Group
     巴马丹拿集团
短句来源
     ] group.
     ]组。
短句来源
     Coordinating Internal Relations in a Business Group
     试论企业集团的内部关系协调
短句来源
     Coordinating Social Relation of Interests through Group Negotiation
     运用集体谈判协调社会利益关系
短句来源
查询“coordinating group”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。
  coordinating group
Cooperative distributed problem-solving systems (CDPS) offer computer methods for coordinating group expertise in the solving of problems.
      
Specifically, this paper suggests creating a multidisciplinary forum or a consultative coordinating group with members from various countries to address globally governance of converging, emerging technologies.
      
This research examines the introduction of computer-based group decision support systems (GDSS) to members of a division level coordinating group.
      
Influence of Computer-Based Meeting Support on Process and Outcomes for a Divisional Coordinating Group
      
The limits and special features of the method for highly flexible structures - especially for the case that the coordinating group is within a flexible chain - are discussed.
      
更多          


A series of monooctyl alkylphosphonates, including o-methylphenylphosphonate (2) and yclohexylphosphonate (3) have been synthesized for the investigation of structural effect of igands in the extraction process.GP(O) (OR) OH G = C_6H_5(1), 0-CH_3C_6H_4(2), C_6H_(11)(3) R -C_8H_(17)(a), C_4H_9CH (C_2H_5)C0H_2 (b), C_6H_(13)CH (OH_3) (c)Tiese acidio organophosphorus ompounds have been prepared successfully in high purity (>99% by potentiometric titration) ither by nucleophilic substitution of tetramethyl ammonium...

A series of monooctyl alkylphosphonates, including o-methylphenylphosphonate (2) and yclohexylphosphonate (3) have been synthesized for the investigation of structural effect of igands in the extraction process.GP(O) (OR) OH G = C_6H_5(1), 0-CH_3C_6H_4(2), C_6H_(11)(3) R -C_8H_(17)(a), C_4H_9CH (C_2H_5)C0H_2 (b), C_6H_(13)CH (OH_3) (c)Tiese acidio organophosphorus ompounds have been prepared successfully in high purity (>99% by potentiometric titration) ither by nucleophilic substitution of tetramethyl ammonium salt of alkylphosphonjc acid with arious isomeric octyl bromides or by controlled alcoholysis of alkylphosphonyl dichloride. The arent alkylphosphonio acids were prepared in usual manner. Substituted phenylphosphonic acids ynthesized by Friedel-Crafts type reaction, in all likelihood, contains both o-and p-isomers. he o-methyl-phenylphosphonio acid has been prepared, however, from o-methylbromobenzene and riethylphosphite via Arbuzov rearrangement catalyzed with nickel chloride, followed by ydrolysis. The syrupy monoootyl alkylphosphonates may be identified as their copper salts or alts with oyclohexyl amine. Both salts are crystallines with sharp melting point, which is ncreased as the branch chain of the ester alkyl group enhanced. The IR spectra of these salts how two new peaks at 1180, 1140 and 1060, 1080 cm~(-1) which are assigned to the POO_(asym)~- nd POO_(sym)~-vibration respectively, instead of stretching vibration of hydrogen bonded P=O nd P-OH in parent acid molecules. It is interesting to state that the differences between POO_asym)~- and POO_(asym)~- are 114 cm~(-1) for oyclohexylamine salts and 76 cm~1 for copper alts (Table 2 and 3 in Chinese Text).The mechanism of extraction of metals by acidic rganophosphorus compound is closely related to the degree of aggregation of ligands in olvent. olecular weight determination by VPO method indicates that all of the compounds investigated Table 4) are dimers in benzene, characteristic for monobasic phosphoric (phosphonic) acids The egree of aggregation keeps constant upon dilution, showing the high bond energy of ntermolecular dimeric structure of monooctyl alkylphosphonates.The distribution ratio (D) of d, Sm, Y and Yb in extraction with monooctyl alkylphosphonates was investigated as a function f hydrogen ion concentration in the aqueous phase and ligand concentration in the organic hase. The D value for a given lanthanides was found to be inversely third power dependent upon he concentration of hydrogen ion (Fig. 1~5) and directly third or 2.5 power dependent upon the oncentration of ligand (Fig. 6~9). Thus the mede of extraction wa~s postulated as equation (1) nd (5). The extraction constant (K_ex) was calculated by equation (4) or (6).As shown in Table r Fig. 10, the K_(ex) for Nd, Sm, Y and Yb in extraction by monooctyl alkylphosphonate are orrelated with the chemical struoture of ligands. In extraction with acidic phosphonate, rouping >P(O)OH acts as coordinating group,which can be measured quantitatively by pK_a value. he reaction constants of Nd,Sm, Y and Yb extraction are increased, as the acidity of ligand is nhanced. The acidities of compounds 1 and 2 are evidently higher than that of 3 owing to the lectronwithdrawing (-I) effect of benzene ring due to conjugation.Solvent extraction may be egarded as complex formation between two phases.This thermodynamic process should evidently be nfluenced by steric effects. This was examined experimentally on various types of phosphorus-ased extractants. As shown in this paper, the K_(ex) of rare earths in extraction by monoootyl yclohexylphosphonate is distinctly lower than that for phenylphosphonate due to the steric indrance arised from boat-chair conformation of the cyclohexyl group. This is especially clear n case of monomethylheptyl cyolohexylphosphonate (3) which may be considered as highly terically hindered ligand. On the other hand, the steric effect of extraction is influenoed lso by the nature of the metal extracted. For example, the K_(ex) of heavy rare earth elements Y and Yb) is usually greater than that for light one (Nd, Sm) due to lanthanide contraction. e an, to a limited extent, design seleotive ligands for extraotion of rare earths, utilizing the terio hindrance in solvent extraction. Unfortunately, it is diffioult to express the steric ffeot quantitatively owing to the fact that the data for E_s values are still insufficient.

为研究稀土萃取分离中萃取剂空间位阻的影响,应用烃基膦酸四甲基氢氧化铵盐与溴代辛烷的亲核取代或烃基膦酰二氯的控制醇解反应,合成不同结构位阻的烃基膦酸单辛酯。它们的环己胺盐与铜盐均为短间距熔点的结晶。在测定烃基膦酸单辛酯在苯中的缔合度、萃取稀土分配比与平衡水相酸度和平衡有机相配位体浓度关系的基础上,确定了它们萃取稀土的机理,并据此计算了萃取钕、钐、镱和钇的平衡常数和萃取稀土的分离因数。不同类型的烃基膦酸单辛酯萃取稀土的平衡常数与分离因素的差别和它们的酸解离常数及空间位阻有关,同类型的烃基膦酸单辛酯的辛基结构对其萃取分离稀土的性能也有影响。

Solvent extraction of metal ions may be regarded as a multicomponental coordinative chemical reaction between two immiscible phases. This thermodynamic process is evidently influenced by the spatial configuration of both ligand and metal ion to be extracted. The steric feature consisting of shielding, conformational and spatial effects are, however, determined by the composition, structure and configuration of the coordination compounds. Steric effects play an important role in the investigation of organic extractants...

Solvent extraction of metal ions may be regarded as a multicomponental coordinative chemical reaction between two immiscible phases. This thermodynamic process is evidently influenced by the spatial configuration of both ligand and metal ion to be extracted. The steric feature consisting of shielding, conformational and spatial effects are, however, determined by the composition, structure and configuration of the coordination compounds. Steric effects play an important role in the investigation of organic extractants with high selectivity. In the mathematical model of the molecular design of extractants, the steric constant is one of the most important terms.The great similarities in chemical and physical properties of rare earths tend to the difficulties in their separation. The present paper describes the successful trial on extractive separation of these elements based on the steric effects of ligands which is enhanced by lanthanide contraction.As shown by our early studies[4] that the spatial configuration of the ester alkyl group in the molecule of dialkyl methylphosphonates has a remarkable effect on the extraction of uranium and thorium. These significant differences were contributed to the steric effect of ligands in the various composition of the extracted species. It is reasonable to predict that similar structural condition exist in the lanthanide extraction as in thorium extraction due to the similar atomic radius and identical composition of the extracted coordination compounds. An evident steric effect of ester alkyl group of both dialkyl phenylphosphonates and dibutyl alkylphosphonates was observed in extraction of cerium, promethium and yttrium. The extraction behaviour of lanthanum, praseodymium, neodymium, samarium and ytterium by dialkyl isopropylphosphonates was influenced in a certain extent by the spatial configuration of the ester alkyl group. The dependence of structural feature of these organophosphorus ligands on the thermodynamic functions △H, △Z and T△S of the extraction reaction are discussed.The structure-reactivity studies of various types of acidic organophosphorus compounds in extraction of light, medium and heavy rare earths as neodymium, samarium, ytterbium and ytterium as representatires demonstrated that both di(2-ethylhexyl)phosphinic acid and di-n-octylphosphinic acids are isomeric compounds with almost the same pKa values, but the difference in their K_(ex) for Nd, Sin, Y and Yb extraction is of four orders of magnitude. This is attributed to the apparent steric hindrance arising from two branched alkyl radical directly linked to the coordinating group. In the former molecule, there are two octyl groups with substituent on the β-position, which inhibit the coordination of the extractants with metal ions. The steric effect in extraction of rare earths was weakened with the increasing in atomic number while the atomic radius was decreased due to the lanthanide contration. Similar structural effects have been found in the extraction of rare earths by dioctyl aralkylphosphonates. The steric effect or acidic organophosphorus ligands on lanthanide extraction is well demonstrated by the fact that the lgK_(ex) and the △S calculated in the extraction reaction of rare earths by 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester increase with the increase of the atomic number and reveals the "tetrad effect".On the basis of experimental data the steric constants of various alkyl and alkyloxyl groups in mono-basic acidic phosphorus ester in extraction of rare earths was estimated.

金属的溶剂萃取是两相间多组成的配位化学反应,配位体及被萃离子的空间结构对这个热力学过程有显著影响,它与形成热力学稳定的配位化合物有关。包括屏蔽效应,构象效应和空间张力在内的结构空间效应不仅决定于配位体及金属离子的结构,同时也与所形成的萃合物的结构和构型直接相联系,它是萃取剂分子设计数学模型中的重要结构参数。 稀土配位化合物一般为八面体构型,结构空间效应的影响不显著,但镧系收缩特性,为应用配位体的结构空间效应提供了可能性。 本文着重讨论了中性磷(膦)酸酯及酸性磷(膦)酸酯萃取稀土反应中的结构空间效应对萃取性能的不同影响,以及与反应的熵变值及萃合物结构的联系,同时对萃取稀土反应中有机取代基团Es值的测定作了探讨。

The effect of the struture of chelating agent and synergetic agent on theextraction separation of lithium isotopes by Sudan I-neutral ligand synergeticextraction systems were discussed in this paper. In order to obtain higher isotopiceffect, the chelating agent must possess weaker acidity (pK_a>11), strongerintramolecular hydrogen bonding and a greater tendency to from a six-memberedchelating ring. In the synergetic agent, there must be a functional group possessingstrong coordination ability without steric...

The effect of the struture of chelating agent and synergetic agent on theextraction separation of lithium isotopes by Sudan I-neutral ligand synergeticextraction systems were discussed in this paper. In order to obtain higher isotopiceffect, the chelating agent must possess weaker acidity (pK_a>11), strongerintramolecular hydrogen bonding and a greater tendency to from a six-memberedchelating ring. In the synergetic agent, there must be a functional group possessingstrong coordination ability without steric hindrance. The separation effect (α)increased with the increase in the basicity of the coordinating group. The increaseof the number of chelating rings in the extractable complex was of benefit to theenhancement of α. Further discussions are also made on the enrichment directionof extraction systems and the prospects of different systems to be used for isotopeseparation.

文章讨论了苏丹I-中性配位体协萃体系萃取分离锂同位素中螯合剂和协萃剂的结构效应。为了获得高的同位素分离效应,螯合剂必须是弱酸性的(PK_α>11),具有强的分子内氢键及易于形成六元螯合环。协萃剂结构不仅要求无空间位阻,而且具有强的配位基。α随配位基的碱性增大而相应提高。萃取络合物中螯合环的增多亦有利于体系α的提高。此外本文还讨论了一些萃取体系的同位素富集方向和萃锂体系用于分离同位素的前景。

 
<< 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coordinating group的内容
在知识搜索中查有关coordinating group的内容
在数字搜索中查有关coordinating group的内容
在概念知识元中查有关coordinating group的内容
在学术趋势中查有关coordinating group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