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transfer
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  “transfer”译为未确定词的双语例句
    Studies of Electrostatic Adsorption Equilibria and Mass Transfer Kinetics of Proteins
    蛋白质静电吸附平衡与动力学的研究
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    Studies on the Proton Transfer Mechanisms and Relevant Properties of Glycinamide and Its Derivatives Associated with the Cis Peptide Bond Units
    与顺式肽键单元相关的甘氨酰胺及其衍生物的质子转移机制及相关性质研究
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    NEW CHARGE TRANSFER COMPLEXES OF 3, 3~′, 5, 5~′- TETRAPHENYL-2, 2~′-DITHIOPYRANYLIDINE WITH 7, 7, 8, 8-TETRACYANO-ρ- QUINODIMETHANE AND IODINE
    3,3',5,5'-四苯基-2,2'-双亚硫杂环己二烯与四氰代对二次甲基苯醌和碘的复合物
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    SYNTHESIS OF NONANUCLEOTIDE (14~22) OF THE DIHYDROURIDINE(D) LOOP OF YEAST ALANINE TRANSFER RNA
    酵母丙氨酸转移核糖核酸双氢尿核苷(D)环区九核苷酸(14~22)的合成
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    INTERVALENT TRANSFER IN AN ORGANO-METALLIC Fe (Ⅲ) -Pd (Ⅱ) CONTAINING COMPLEX
    含钯(Ⅱ)-铁(Ⅲ)混合价金属有机化合物的研究──FcCH_2N(CH_3)_2-Pd-X-L类金属有机化合物的电化学性质和价电子互换作用
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  transfer
Using these monomial bases we prove that the image of the transfer for a general linear group over a finite field is a principal ideal in the ring of invariants.
      
The weighted inequalities allow us to transfer the result to the ergodic case, when the operator is induced by a mean bounded, invertible, positive groups.
      
A gene regulatory mechanism has been proposed in which steroid hormones and certain other drugs bind to nuclear receptor proteins followed by transfer to DNA where they are inserted between base pairs.
      
3D QSAR STUDIES OF INHIBITORS OF CHOLESTEROL ESTER TRANSFER PROTEIN (CETP) BY CoMFA, CoMSIA AND GFA METHODOLOGIES
      
A boundary element method for a nonlinear boundary value problem in steady-state heat transfer in dimension three
      
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The first step in caprolactam polymerization is an addition polymerization. The authors have studied the initiative influence of various substances on the polymerization and obtained the following results. The initiators of the free radical type, such as benzoyl peroxide and hydrogen peroxide together with their redox systems, all exerted no effect on caprolactam. While carboxylic acids gave only weak initiative effect in absence of water and amines gave no action, the mixtures of acids and amines and of acids...

The first step in caprolactam polymerization is an addition polymerization. The authors have studied the initiative influence of various substances on the polymerization and obtained the following results. The initiators of the free radical type, such as benzoyl peroxide and hydrogen peroxide together with their redox systems, all exerted no effect on caprolactam. While carboxylic acids gave only weak initiative effect in absence of water and amines gave no action, the mixtures of acids and amines and of acids and water initiated the polymerization rapidly. Amino-acids of various types also gave rapid initiation. 6-Benzoyl-amino-caproic acid was found to be far inferior in the initiative activity than benzoic acid. Trimethylphenyl ammonium iodide did not initiate the polymerization, and attempt to polymerize N-methyl caprolactam gave negative results.From these facts, the polymerization of caprolactam is clearly neither of free radical nor of step-wise addition mechanism. The authors suggest that the initiation is exerted by both the cation and anion of the initiator. These ions activate the amide grouping by a proton transfer mechanism, which causes caprolactam to polarize in the type of a zwitter-ion and thereafter polymerization proceeds.

己內醯胺聚合的最初階段為加成聚合。作者研究若干種化合物,試驗它們對己內醯胺聚合的引發作用。結果,自由基型的引發劑如過氧化苯甲醯,過氧化氫和它們的氧化還原體系,均不能引發己內醯胺的聚合。羧酸在無水存在時其引發作用甚弱。胺類則缺乏引發效應。但羧酸与胺同時存在時能迅速的引起己內醯胺的聚合。氨基酸不論何種類型均有迅速的引發作用。苯甲醯胺基己酸的引發作用遠較苯甲酸為差。碘化三甲基苯基銨(季銨鹽)不能引發己內醯胺的聚合,而N-甲基己內醯胺也不能用這些引發劑引起聚合。根據以上結果,己內醯胺聚合顯非自由基型的聚合,亦非引發劑与單體的逐步加成。作者建議引發劑的正負兩種離子都有影響。引發機構是由於氫原子的轉移,使己內醯胺發生雙離子式的極化,因而發生聚合。

A new method for the separation of traces of rhenium by the method ofcoprecipitation has been proposed. It was successfully applied to the deter-mination of rhenium in molybdenite, which compared well with the well-knowndistillation method and the extraction method in accuracy and precision. From 10 to 100 micrograms of rhenium as perrhenate are completelycoprecipitated with tetraphenyl arsonium perchlorate obtained from about 0.4ml of 1% potassium perchlorate solution and 3 ml of 0.7% tetraphenyl arson-ium...

A new method for the separation of traces of rhenium by the method ofcoprecipitation has been proposed. It was successfully applied to the deter-mination of rhenium in molybdenite, which compared well with the well-knowndistillation method and the extraction method in accuracy and precision. From 10 to 100 micrograms of rhenium as perrhenate are completelycoprecipitated with tetraphenyl arsonium perchlorate obtained from about 0.4ml of 1% potassium perchlorate solution and 3 ml of 0.7% tetraphenyl arson-ium chloride solution. Precipitation can be carried out in either neutral, acid(hydrohloric or tartaric acid) or alkaline solution (sodium bicarbonate, car-bonate, hydroxide or ammonia). The recovery of rhenium is above 99%. When coprecipitation is carried out in about 50 ml. of solution containingone gram each of sodium chloride and sodium hydroxide and the precipitatewashed with 0.5% sodium hydroxide containing tetraphenyl arsonium chloride,perrhenate can be separated from considerable amounts of molybdate, unlessthe quantity of molybdenium exceeds 0.88 gm. In the latter case, the washedprecipitate can be made free from molybdate by dissolving it in hot water,adding more tetraphenyl arsonium chloride and potassium perchlorate solutionsand cooling the mixture to room temperature. Under these conditions, otheranions--zincate, aluminate, nitrate, phosphate, arsenite, arsenate, vanadate, sele-nite, chromite, chromate and tungstate--do not interfere. By dissolving the precipitate in hot water, adding an excess of perchloricacid and cooling, rhenium can be brought into solution. A modified procedurefor the colorimetric determination of rhenium by the Geilmann reaction in thepresence of perchloric acid is developed. Up to 50 micrograms of rhenium canbe separated and determined. A method for the determination of rhenium in molybdenite is proposed.Recommended procedure is as follows: A sample of molybdenite is weighed out so as to contain 10--50 microgramsof rhenium. It is fused with sodium hydroxide and sodium peroxide accor- ding to the method of Malouf and White. The aqueous extract of the melt(about 50 ml) is filtered from the ferric hydroxide precipitate and washed withhot water. The solution is then partially neutralized with hydrorhloric acid,leaving 1--2 gm of sodium hydroxide in solution. Three ml of 0.7% tetraph-enyl arsonium chloride solution are added, followed by seven drops (ca 0.4 ml)of 1% potassium perchlorate solution, added drop by drop during a period ofthree to four minutes. After standing ten minutes, the precipitate is filteredand washed four times with a 0.5% sodium hydroxide solution containing 0.014%tetraphenyl arsonium chloride. The precipitate is washed back with distilled water into the beaker inwhich precipitation was carried out. After adding water to about 50 ml andheating to dissolve the precipitate, 1 gm each of sodium chloride and sodiumhydroxide are dissolved therein and 2 ml of the tetraphenyl arsonium chloridesolution are added. One drop of potassium perchlorate solution is added aftercooling and the mixture is allowed to stand for ten minutes. The precipitateis filtered through the original filter and washed four times with the samewash solution. The precipitate is again washed back to the original beaker with distilledwater and more water is added to about 35 m1. The mixture is heated untilthe precipitate is completely dissolved and 1 ml of 60% perchloric acid is added.After cooling, the precipitate is filtered and washed with 1 : 100 perchloric acid.In this way, perrhenate in the precipitate can be brought into solution. The colorimetric determination of rhenium is essentially that of Hurd andBabler, with modifications. To the combined filtrate and washings whichcontains about 1 ml of eoncentrated perchloric acid in a volume 45--55 ml, areadded 3.5 ml of concentrated hydrochloric acid, 2 ml of 20% sodium thiocyan-ate solution and 1 ml of 20% stannous chloride in 1 : 1 hydrochloric acid. Afterten minutes, the solution is extracted with three portions of ether. The extra-cts are transferred into a 35 ml (or 50 ml) volumetric flask and diluted to themark. The optical density of the ether extract is then measured with anelectrophotometer using a blue (350--500 mμ) filter. Four samples of molybdenite were analyzed by this method and also by thedistillation method of Hiskey and Meloche and the extraction method ofBeeston and Lewis. The results are given in the last table of the Chinesetext. An analysis by this method requires about 2(1/4) hours.

从酸性、中性或碱性溶液里,微量高铼酸根都可以相当完全和高氯酸四苯基鉮共沉淀。在碱性溶液中,用共沉淀法可使微量高铼酸根与大量钼酸根及其他阴离子分离。如果钼的含量特别大.再沉淀一次可使分离完全。将沉淀溶解於热水後加入高氯酸,可使其中的高铼酸转入溶液,并可直接进行比色测定。本文提出一种简单、迅速而易於控制的新方法以测定辉钼矿中的铼。精密度与准确度与蒸馏法、萃取法接近。

A mongst hundreds of analogues of chloramphenicol, which have so far beensynthesized and studied for their relationships between chemical constitutionand biological action, one concept is to curtail the hydroxymethyl group in the structure of chloramphenicol to form a simpler compound, 1-(p-nitrophenyl)-2-dichloroacetamido-ethanol (II), in which one asymmetric carbon being eli-minated. By so doing, however, the antibiotic activity is greatly reduced.We thought that the cause of loss of activity might be due...

A mongst hundreds of analogues of chloramphenicol, which have so far beensynthesized and studied for their relationships between chemical constitutionand biological action, one concept is to curtail the hydroxymethyl group in the structure of chloramphenicol to form a simpler compound, 1-(p-nitrophenyl)-2-dichloroacetamido-ethanol (II), in which one asymmetric carbon being eli-minated. By so doing, however, the antibiotic activity is greatly reduced.We thought that the cause of loss of activity might be due to the disappea-rance of chelating structure, which is regarded to be necessary for the exhibi-ting of antibiotic activity, between two hydroxyl groups as present in themolecule of chloramphenicol (I). In this investigation, therefore, the authorshave devised, on the one band, a compound, 1-(o-hydroxymethyl-p-nitrophenyl)-2-dichloroacetamido-ethanol (III), in which the hydroxymethyl group is retainedbut shifted from the propanediol side chain to benzene ring at the positionortho to the secondary alcoholic group so as to make the two hydroxyl groupsstill capable of chelating with one another. The second compound, 1-(o-hydroxy-p-nitrophenyl)-2-dichloroacetamido-ethanol (IV), is so designed that thehydroxymethyl group being changed to a hydroxyl group, which also shiftedto the same position as in compound III. Besides, 1-(o-methoxy-p-nitrophenyl)-2-dichloroacetamido-ethanol (VI), in which the hydroxyl group is masked bymethylation, has been prepared for the purpose of comparison. The results of antibacterial tests against both Gram-positive and Gram-negative bacteria showed that the activity of compound III, IV, VI was alsogreatly reduced as compared with that of chloramphenicol. This is in line withthe conclusion drawn by other investigators, who suggested that the prop-anediol moiety being vital to the exhibiting of antibiotic action of chloramphe-nicol. Compound III was prepared by a 11-step synthesis starting from o-amino-p-nitroethylbenzene (VII). The latter was converted to 2-ethyl-5-nitro-benzo-nitrile (VIII), m. p. 73.5°, yield 44%, by Sandmeyer reaction. The nitrile wasthen hydrolyzed to 2-ethyl-5-nitrobenzoic acid (IX), yield 90.5%; and subse-quently transferred to its methyl ester (X), b. p. 118--120°/1 mm, m. p. 36--37°,yield 90.5%, by usual way. The ethyl group of X was oxidized to acetyl groupby chromium trioxide to form 2-carbomethoxy-4-nitroacetophenone (XI), yield56.6%. α-Amino-2-carbomethoxy-4-nitroacetophenone hydrochloride (XIV) wasprepared by Delepine reaction, first by converting XI to α-bromo-2-Carbome-thoxy-4-nitroacetophenone (XII), followed by transferring the bromo-compoundto urotropine double salt (XIII), m. p. 147--149°, yield 46.5%, and finally byhydrolyzing the latter with hydrochloric acid. The amine (XIV), withoutisolating pure, was acetylated to α-acetamido-2-carbomethoxy-4-nitroacetophenone(XV), m. p. 168--l72°, yield 51.2%; which was then reduced by lithium aluminiumhydride to 1-(o-hydroxymethyl-p-nitrophenyl)-2-acetamido-ethanol (XVI), m. p.175--176°, yield 23.6%. The requiring product III, m. p. 136--137°, yield 66%,was obtained by substituting the acetyl group in compound XVII with dichlo-roacetyl group, first by hydrolyzing to free amine (XVII), m. p. 172--173°(dec),yield 72%, and treating the latter with methyl dichloroacetate. Compound IV, m. p. 143--144°, and compound VI, m. p. 94.5--96°, were bothprepared from the corresponding carbonyl compounds, α-dichloroacetamido-2-hydroxy (or methoxy)-4-nitroacetophenone (V, or XVIII) by Meerwein-Ponn-dorf reduction in, 13% and 47% yield respectively.

1.从隣氨基-对硝基乙苯开始,经过十一个步骤合成1-(隣羟甲基-对硝基苯)-2-二氯乙酰胺基乙醇。此化合物没有氯霉素的原有抗菌作用,因此说明氯霉素结构上的羟甲基移位后虽然仍可能有氢键钳环结构也不能维持原有抗生作用。 2.α-二氯乙酰胺基-隣羟(或甲氧基)-对硝基苯乙酮经异丙醇铝还原获得1-(隣羟(或甲氧基)-对硝基苯-2-二氯乙酰胺基乙醇,此二化合物的抗菌作用也小於氯霉素。

 
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