查询词典 anion

The impact of anion over respiratory system is the most obvious , this is that it can improve people's vital capacity because of the anion is by the fact that pneogaster enters the human body's.

负离子对呼吸系统的影响最明显，这是因为负离子是通过呼吸道进入人体的，它可以提高人的肺活量。

For the metal-oxygen clusters containing tungsten, the pyrolysis procedure of potassium salt with [P2W18O62]6-anion is similar to that of metal-oxygen clusters with [P2Mo18O62]6-anion, whenas the NH4+, Cu2+salts of [P2W18O62]6-seem to decompose directly into WO3 at 400 ℃, 450 ℃,respectively.

以钨为配位原子的钾盐在410 ℃也有相似的行为，但铵盐和铜盐却没有观察到类似的热重排现象，分别在400 ℃， 450 ℃直接热分解为WO3。

However, in the setting of an elevated serum anion gap acidosis, other anions such as acetoacetate or lactate are present, thus rendering the urinary anion gap a useless test.

但是在阴离子间隙增大的酸中毒中存在其它的阴离子，如酮酸酸中毒时的乙酸乙酯或乳酸酸中毒时的乳酸。这时检测尿阴离子间隙就没有什么意义了。

However, in the setting of an elevated serum anion gap acidosis, other anions such as acetoacetate or lactate are present, thus render ing the urinary anion gap a useless test.

但是在阴离子间隙增大的酸中毒中存在其它的阴离子，如酮酸酸中毒时的乙酸乙酯或乳酸酸中毒时的乳酸。这时检测尿阴离子间隙就没有什么意义了。

Chelate fiber with amidoxime group,which is obtained from chemical modification of PAN fiber,is treated with mercury nitrate to prepare anion-exchange fiber.The optimum conditions of the anion-exchange fiber absorption of the thiocyanate ion,such as ion concentration,time,the pH value were studied.

以聚丙烯腈纤维进行NH2OH化学改性制得的含有偕胺肟基的螯合纤维为原料，经Hg(NO3)2化学处理，制得阴离子交换纤维；并以硫氰酸根离子为研究对象，系统地探讨和研究了阴离子交换纤维吸附硫氰酸根离子的最佳条件参数：离子浓度、时间、pH值等。

Three new ferrocenylmethyl-substituted indenes and cyclopentadienes were synthesized by the addition of hydrogen anion and carbon anion to fulvene and benzofulvene respectively, moreover, their structures were characterized by NMR and MS.

本文以二茂铁基富烯和二茂铁基苯并富烯为前体，通过负氢和负碳对双键的加成，合成了3个新型的二茂铁基甲基取代的茚及环戊二烯，并对其结构进行了核磁及质谱表征。

In this thesis,the AM1,MNDO,MINDO/3(mainly AM1)and INDO/S-CI semiempirical MO methods were used toinvestigate the excited-state intramolecular protontransfer reactions of salicylic acid derivatives—salicylic acid,methyl salicylate,salicylaldehyde,o-hydroxyaceto-phenone,salicylamide and 3-hydroxy-picolinamide (6 conformers and 2-3 anion species);2-(2'-hydroxy-5' methylphenyl) benzotriazole(4 conformers),2-(2' hydroxyphenyl) benzimidazole (3 conformers and 3anion species),Bis-2,5-(2-benzoxazolyl)hydroquinone(3 conformers),2-(2'-hydroxyphenyl)benzothiazole(2conformers) and 7-azaindole dimer (2 conformers).Theinvestigations were described as follows.Geometry optimization,relative stability andhydrogen bonding energy First,for sylicylic acid derivative molecules,the AM1,MNDO and MINDO/3 methods were used toinvestigate ground-state geometry optimization,energies,relative stabilities and hydrogen-bondingenergies on the five kinds of the molecules(designing 6 conformers and 2-3 anion species).Comparing with experimental data,the optimizedgeometry,the order of stability,the hydrogen-bonding energies and the distances between O-O in O-H..O hydrogen bonds by AM1 method were in agreementwith the experimental data,however,the C-C bondlengths optimized by MNDO and MINDO/3 were longer,C-O and O-H bond lengths were shorter;for C-N bondlengths,the results opitimized by MNDO method werethe same as those by AM1 method,nevertheless the C-Nbond lengths given by MINDO/3 method were muchshorter.For some sylicylic acid derivatives(e.g.methyl salicylate,salicylamide),the order ofstabilities on the conformers given by MNDO andMINDO/3 methods were not in agreement with theexisting conformers deduced by experimental methods,and the hydrogen bonding energies calculated by MNDO.and MINDO/3 methods were smaller.Second,the studyon the other systems found that the optimizedgeometry of the proton-transfered product with INDOmethod could not be obtained,only could theoptimized geometry of reactant be obtained,and thecalculated hydrogen bonding energies were greater.Many results of calculation indicated that the studyon the excited-state intramolecular proton transferreaction system using AM1 method was suitable andreliable.

本论文用AM1、MNDO、MINDO/3（主要是AM1）和INDO/S-CI半经验分子轨道方法对水杨酸衍生物系列——水杨酸、水杨酸甲酯、水杨醛、O-羟基乙酰苯酮、水杨酰胺和3-羟基吡啶酰胺（6种异构体和2-3种阴离子）；2-（2'-羟基-5'-甲基苯基）苯并三〓唑（4种异构体）；2-（2'-羟基苯基）苯并咪唑（3种异构体和3种阴离子）；2，5-二间氮杂氧茚氢醌（3种异构体）；2-（2'-羟基苯基）间〓杂硫茚（2种异构体）和7-〓吲哚二体（2种异构体）的激发态分子内质子转移反应在以下几个方面进行了较系统的理论研究：几何构型优化和相对稳定性及氢键能首先以水杨酸衍生物系列分子为例，用AM1、MNDO和MINDO/3方法考察了5种分子（每种分子设计6种异构体和2-3种阴离子）的基态几何构型优化，能量、相对稳定性和氢键能计算，通过和实验数据进行比较，AM1方法给出的优化几何构型、稳定性次序、氢键能和O—H。。。O氢键的0—0距离与实验数据吻合最好，MNDO和MINDO/3方法优化的C-C键长偏长，C-O键和O-H键长偏短；对于C-N键长，MNDO和AM1优化结果差别不大，而MINDO/3给出了过短的C-N键长，MNDO和MINDO/3方法给出的有些水杨酸衍生物分子（如水杨酸甲酯和水杨酰胺）异构体的稳定性次序和实验上推测的可存在异构体结果不一致，MNDO和MINDO/3方法给出的氢键能偏低，对其他体系的研究发现INDO方法常常不能得到质子转移产物的优化几何构型，只能得到反应物的优化构型，并且估算的氢键能偏高，大量的计算结果表明AM1方法对本论文研究的激发态分子内质子转移反应体系是适宜和可靠的。

The tryptophan residues play important roles in DNA photoreactivation catalyzed by CPD photolyases. We have investigated the action mechanism concerning Trp in DNA photoreactivation, and obtained the results as follows: 1 We proposed a mechanism of photosensitized splitting of CPDs by Trp and Trp-containing peptides. 2 Quantum yields of splitting of the model compounds that a Trp linked covalently a CPD were obtained under 290 nm light in various solvents, these values changing with solvent, range from 0.01 to 0.5. 3 Utilizing pulse radiolysis technique, splitting processes were observed in aqueous solution of the CPDs with hydrated electron and some oxidative species (such as hydroxyl radical, bromic radical and azide radical), and obtained their rate constants. In the case of interaction between CPD and hydrated electron, splitting of the CPD anion, and pyrimidine anion transfer an electron to FAD or Rf, were observed. The process rate was slower one order more than that in photolyase. Minor, but highly mutagenic UV-light-induced lesions are (6-4) photoproducts, which are repaired by (6-4) photolyases. These enzymes, discovered in 1993, are not well characterized and their mechanism is still under investigation.

我们研究它的作用机理，获得以下结果：1）建立了色氨酸及其肽对嘧啶二聚体光敏化裂解的直接修复作用机理模型；2）获得了色氨酸共价键连接于嘧啶二聚体的化合物在多种溶剂中290nm光辐照裂解的量子效率，其值随溶剂而变化，范围在0.01-0.5；3）运用脉冲辐解观察到嘧啶二聚体与水合电子和一些氧化性的自由基作用裂解过程，得到相应速率常数；对二聚体与水合电子作用发生裂解以及向FAD返还电子的过程进行了体外模拟；4）（6-4）光解酶的作用机理中一个关键假定是氧杂环丁烷中间体在接受电子后能自发裂解，恢复二嘧啶的结构。

The possible mechanism for the two ECL channels at the Pt electrode cathodically pre-polarized in alkaline solution is also proposed:(1) luminol anion was electroxidized to radical at 0.22V, which then reacted with the oxygen dissolved in solution and emitted light;(2) the fresh oxygen species electro- generated at 1.07V oxidized luminol anion with light emission.

同时给出了在碱性含氧溶液中预还原的铂电极上两个可能的ECL反应通道：(1)在0.22V鲁米诺阴离子氧化为鲁米诺自由基，然后与溶解氧反应而发光；(2)1.07V处析出的新鲜氧与鲁米诺阴离子反应而发光。

Its mechanism is the use of anthraquinone in alkali conditions off proton surface forming 10 more stable carbon anion face, but because carbon anion and oxygen ion exist between testosterone and enolate type each other changes, cause reaction product complex, at least five, reaction selectivity, product yield, separation difficulties, and product purity is not high, therefore, using the type and quantity of alkali, phase transfer catalyst type, solvent, to optimize the selection process conditions so as to improve the yield target product.

其机理是利用蒽酮在碱存在的条件下脱去氢质子面形成10位较稳定的碳负离子面进行，但是因为碳负离子和氧负离子之间存在酮式和烯醇式的互变，导致反应复杂，产物至少有五种，反应选择性差，产物分离困难，产率低，且产品纯度不高，因此，利用对碱的种类和量的多少，相转移催化剂的种类，反应溶剂的选择，来优化反应工艺条件从而提高目标产物的产率。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。