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61.
62.
随着我国社会主义建设事业的发展,三废治理的重要性日益突出。溶剂萃取法具有高选择性,高萃取率及从低浓度溶液中提取分离有机及无机化合物的特点,它既可直接处理工业废水,回收化工原料,化害为利,又可用于工艺改革代替沉淀法或代替原来需用有毒物质的化工操作,从而杜绝三废产生,成为无公害工艺。近年来由于三槽充气器,培纳油水分离器及微粒浮集设备的应用,使有机相的夹带大幅度降低,为萃取技术在三废治理中的应用创造了有利条件。改革冶炼工艺,消除三废应用萃取流程来改革冶炼工艺是冶金工业中治理三废的重要途径。如在有色金属的经典冶炼过程中,经常有大量氧化硫等腐蚀性废气、酸性有害废水及废 相似文献
63.
A series of substituent constants for steric effect E_(PA)~(RE) was estimated for the structure and reac-tivity studies of monobasic phosphorus esters in rare earth extraction based on the general conceptionsuggested by us that the extraction behaviours of a ligand are determined chiefly by the polar andsteric effects of the substituents, while the σ~p was proposed as an empirical structure parameterfor the polarity. A good result in correlation analysis was obtained when using these parametersin different extraction systems. The E_(PA)~(RE) is, however, correlated linearly with Charton's υ. Thesummation of polar and steric effects in an extractant can be evaluated by using additivity rule.The calculated extraction equilibrium constant was in good agreement with the experimentaldata. These constants have given the important structural information in the molecular design ofnew extractants. 相似文献
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65.
本文在确定了一元烷基磷(膦)酸酯萃取稀土的性能主要决定于取代基极性和立体效应的基础上,在继长碳链烷基及烷氧基极性参数σ~P后,又提出了这类化合物萃取稀土反应中的取代基立体参数E_(PA)~(RE)。将这类参数应用到其他的萃取体系也获得良好的相关关系。与反映取代基空间效应的Charton的v参数比较,其E_(PA)~(RE)与v间具良好的线性关系。根据加和性规则,可以求得萃取剂分子中取代基因极性参数和立体参数的总和。由此可计算或预测某些萃取剂的性能,实验值与计算值很接近,这对设计新萃取剂很有帮助,在萃取剂分子设计数学模型的建立中,它提供了重要的结构参数。 相似文献
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67.
本文报道α-砜基碳阴离子和磷酰氯的反应,提供了合成α-砜基膦酸酯和α,β-不饱和砜的新方法,此方法具有原料易得、反应步骤少、得率较高等优点.还讨论了α-芳砜基膦酸酯的质谱. 相似文献
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有机磷化合物的研究 VIII. 酸性有机磷化合物的气相色谱 总被引:1,自引:0,他引:1
Acidic organophosphorus compounds may be identified by GLC via their methyl esters, usually prepared from diazomethane. The wide applications of this mthod are, however, limited by the toxicity of diazomethane. Tetramethyl ammonium hydroxide in methanol solution reacted rapidly with acidic organophosphorus compounds at room temperature to form tetramethyl ammonium salts, which were then converted to the corresponding methyl esters by pyrolysis at 300-350 deg.C. A simple and convenient method for separation and identification of various types of acidic phosphates, phosphonates and phosphinates by GLC has been developed. The GLC behaviours of phosphoric acid dialkyl esters, mono-esters of phenyl-and cyclohexyl-phosphonic acids as well as dialkylphosphinic acids can be represented by corrected retention time (t'R) which correlates linearly with the number of carbon atoms of the alkyl groups in these organophosphorus compounds. The influence of number of carbon atoms and isomerization of alkyl group on t'R values and retention index (I) calculated by Kovats equation was discussed. As shown by our experiments the change in retention index (ΔI) in the homologous series of phosphoric acid dialkyl esters is nearly a constant on lengthening the alkyl group of the esters with methylene linkages. 相似文献
70.
The formation of P -- C bond is one of the important problems in synthetic organophosphorous chemistry. This paper describes the study of the formation of P -- C linkage via phosphorylation of carbon atom containing active hydrogen. p-Substituted phenylacetonitrile possessing an active methylene group undergoes stepwise C -- phosphorylation smoothly with diethyl phosphoryl chloride in the presence of naphthalene-sodium. Phosphonyl chloride reacts analogously. Being a deprotonizing agent naphthalene-sodium is distinguished by its availability, effectiveness and mild reaction conditions. The presence of an electron-withdrawing group in the benzene ring reduces the yield of phosphorylation seriously. The chemical shift of ^3^1P NMR of the resulted α-cyano-benzylphosphonates (1) correlates linearly with the Hammett \s\ constants of the substituents. As indicated by ^1H NMR studies the protons in the ester ethyl groups are magnetically nonequivalent. Compound 1 can be alkylated with alkyl halide or condensed with aromatic aldehyde by Hornor-Wittig type reaction due to the presence of active hydrogen atom. The structure-reactivity studies of diethyl phosphoryl chloride on reacting with various β- and β-diketones and β-keto esters (5) as regiospecific reaction were reported. The influences of metal ions in the enolates on the reactivity of the latter were examined and discussed. Only vinyl phosphates with predominantly Z configuration have been isolated exclusively. The C atom with an active hydrogen in the β-diketones investigated is inert to phosphorylation. These experimental results are well supported by reaction selectivity in terms of Eqo/Ecoc based on EHMO calculation. 相似文献