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131.
GDX树脂和二氧六环的理化性质对水中酚类污染物富集洗脱性能的影响 总被引:1,自引:0,他引:1
以9种一元酚为吸附质,系统讨论了GDX-502和二氧六环的理化性质对酚类富集及洗脱性能的影响。结果表明,GDX-502使用前的溶剂预处理具有净化树脂和改变树脂的孔结构的双重功能,用本文方法对GDX-502进行溶剂预处理,可使树脂获得有利于酚类富集与洗脱的孔结构,该树脂对水中酚类的富集作用是以Van der Waals力和较氢键弱的π-键合作用力为基础的物理吸附,而二氧六环洗脱酚类的实质是氢键作用。 相似文献
132.
Gas chromatographic analysis of water phenolic pollutants using acid-washed graphitised carbon black
Summary The fractionation of eleven phenols which may be contaminants in drinking water has been accomplished by using acid-washed graphitised carbon black modified with trimesic acid and PEG 20 M. 相似文献
133.
Twenty three compounds were isolated from the bark of Pinus armandii. These compounds include nine serratenes (1-9), a norserratenone 10, eight phenols 11-18, two flavonoids 19-20, one lignan 21, a diterpene 22 and a novel triterpendiol acetonide 23. Their structures were determined from their physical and spectral properties. 相似文献
134.
Paul D. Ahn Roger Bishop Donald C. Craig Marcia L. Scudder 《Journal of inclusion phenomena and macrocyclic chemistry》1995,23(4):313-327
The 1,5-dichloro-(1) and 1,5-dibromo-(2) naphthalene-2,6-diols form isostructural lattices incorporating ...O–H...O–H...O–H... hydrogen bonding surrounding 21 screw axes. Each phenolic hydroxy group participates in one donor and one acceptor hydrogen bond. When crystallised from dioxane, both compounds form new 1:1 co-crystalline materials whose lattices are closely related but not isostructural. All inter-phenolic hydrogen bonding is now absent with each hydroxy group acting instead as a donor to a dioxane oxygen atom. In consequence, the hydrogen bonded layer structures of pure1 or2 are now replaced by hydrogen bonded chain arrangements. All four crystal structures are analysed and compared in crystal engineering terms through discussion of the various types of other weak intermolecular attractions involved in their lattice constructions.
Supplementary Data relating to this article are deposited with the British Library as supplementary publication No. SUP 82202 (19 pages). 相似文献
135.
酚类聚合物在水相胶束中的酶促合成 总被引:3,自引:1,他引:3
本文报道辣根过氧化物酶在水相胶束中催化聚合取代酚类的研究。水相胶束中酶催化活力高,产物分子量均一;通过调节表面活笥剂和单体的浓度,可以有效地控制产物的分子量,从而建立了不同聚合度有机纳米材料酶促合成的新方法。产物具有较强的蓝紫色荧光及较好的耐热性能,是一种很有应用前景的蓝光材料。 相似文献
136.
Zinc oxide (ZnO) is a highly efficient catalyst for the acylation of a variety of alcohols, phenols and amines with acid chlorides or acid anhydrides under solvent free conditions. Primary, secondary, tertiary, allylic and benzylic alcohols, diols and phenols with electron donating or withdrawing substituents can be easily acylated in good to excellent yield. 相似文献
137.
1,3‐Dibromo‐5,5‐dimethylhydantoin (DBDMH) is found to be an effective catalyst for trimethylsilylation various alcohols and phenols with hexamethyldisilazane (HMDS) in dichloromethane at room temperature. 相似文献
138.
Summary The influence of ionic compounds added to an aqueous methanol eluent on the retention behaviour of sulphonic, carboxylic acids
and of phenols is demonstrated. Absolute and relative retentions can be optimized by changing the water-methanol concentrations.
The optimum conditions for the separation of technical important sulphonic and carboxylic acids (dye intermediates) are shown. 相似文献
139.
Summary Coal wastewaters taken from a pond near Leipzig have been analyzed quantitatively and qualitatively by GC-MS. Most of the organic constituents were pollutants; they included mainly phenol and alkylphenols. Whereas the identities of the main organic contaminants varied little between surface and deep water, the concentration of pollutants in the deeper water was considerably higher. Methodical investigation of interactions between organic pollutants of differentpolarity and aquatic humic substances showed that phenols, among them highly chlorinated and nitrated derivatives, were bound by humic matter. On changing the pH value from ca 7 to 2, all the adsorbed pollutants were released. 相似文献
140.
Mahugo Santana C Sosa Ferrera Z Santana Rodríguez JJ 《Analytical and bioanalytical chemistry》2005,382(1):125-133
A non-ionic surfactant, polyoxyethylene 10 lauryl ether (POLE), was used for the microwave-assisted extraction (MAE) of priority phenolic compounds from soil samples. A central composite design was applied to optimize the extraction parameters, namely, time and power. Under the optimized conditions, the method was applied to different soil samples in order to analyze the influence of soil characteristics on the phenol extraction. Results demonstrated that most of these compounds can be recovered from the soils investigated in good yields (higher than 80%). The standard deviation is lower than 9% (n = 6) for most analytes. Validation of the method by analyzing a reference soil sample containing eight phenols and a comparison with Soxhlet extraction are also reported. 相似文献