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91.
L. S. Vasil'ev F. E. Surzhikov O. G. Azarevich V. S. Bogdanov V. A. Dorokhov 《Russian Chemical Bulletin》1996,45(11):2574-2577
Schemes for synthesizing 3-acyl-4-amino(hydroxy)-2-trifluoromethylpyridines from 3-acyl 4-amino-5,5,5-trifluoro-3-penten-2-ones via their diphenylboron chelate complexes have been suggested.Translated fromlzvestiyn Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2715–2718, November, 1996, 相似文献
92.
93.
2-(H-酸偶氮)-4,5-二硝基苯酚与钍的显色反应研究及其应用 总被引:1,自引:0,他引:1
研究了 2 (H 酸偶氮 ) 4 ,5二硝基苯酚 (HADNP)与钍的显色反应 ,在 pH 5 .5HOAc NaOAc缓冲介质中 ,溴化十六烷基吡啶 (CPB)存在下 ,HADNP与钍反应生成 2∶1稳定紫红色络合物 ,λmax=6 2 0nm ,ε =1.2 3× 10 5L·mol- 1·cm- 1。钍含量在 0~ 30 μg/2 5ml内符合比耳定律 ,方法用于环境水样品中钍含量的测定 ,结果满意。 相似文献
94.
95.
Heung Soo Baek Byung Woo Yoo Sam Rok Keum Cheol Min Yoon Sung Hoon Kim Joong Hyup Kim 《合成通讯》2013,43(1):31-38
α-Haloketones reacted with acyl cyanides to form 1,3-diketones in the presence of samarium diiodide. The reaction was assumed to proceed via a mechanism involving samarium enolates formed in situ from α-haloketones. 相似文献
96.
A series of 3,3′‐(benzylene)bis(4‐hydroxy‐2H‐chromen‐2‐one) derivatives have been synthesized from condensation reactions of 4‐hydroxycoumarin with benzaldehydes under thermal solvent‐free conditions. This environmentally friendly synthesis is uncatalyzed and affords the desired products in excellent yields. 相似文献
97.
《应用有机金属化学》2017,31(5)
A new 4‐hydroxy‐3‐carboxycoumarin ligand and its ruthenium(II) complexes ( 1 – 5 ) have been synthesized, characterized and screened for their in vitro antibacterial activity against a range of Gram‐positive and Gram‐negative bacteria. In addition, compounds 1 – 5 were investigated for antioxidant activities using superoxide radical, 2,2‐diphenyl‐1‐picrylhydrazyl radical and hydroxyl radical scavenging assays, in which most of them displayed significant antioxidant activities. Furthermore, compounds 1 – 5 were evaluated for anti‐inflammatory activity using indirect haemolytic and lipoxygenase inhibition assays and revealed good activity. The new complexes were characterized using spectroscopic methods in addition to elemental analysis. 相似文献
98.
In the presence of a catalytic amount of amino acid hydrochloride, trans‐β‐phenylglycidic ester undergoes ring opening with high stereo‐ and regioselectivity when treated with glycine esters. Alkylation of the resulting β‐amino‐α‐hydroxy diesters with benzyl bromide, followed by cyclization to furnish the expected 1,4‐oxazin‐2‐ones, is also described. 相似文献
99.
The biotransformation of nodakenetin (NANI) by rat liver microsomes in vitro was investigated. Two major polar metabolites were produced by liver microsomes from phenobarbital‐pretreated rats and detected by reversed‐phase high‐performance liquid chromatography (RP‐HPLC) analysis. The chemical structures of two metabolites were firmly identified as 3′(R)‐hydroxy‐nodakenetin‐3′‐ol and 3′(S)‐hydroxy‐nodakenetin‐3′‐ol, respectively, on the basis of their 1H‐NMR, MS and optical rotation analysis. The latter was a new compound. A sensitive, selective and simple RP‐HPLC method has been developed for the simultaneous determination of NANI and its two major metabolites in rat liver microsomes. Chromatographic conditions comprise a C18 column, a mobile phase with MeOH‐H2O (40 : 60, v/v), a total run time of 40 min, and ultraviolet absorbance detection at 330 nm. In the rat heat‐inactivated liver microsomal supernatant, the lower limits of detection and quantification of metabolite I, metabolite II and NANI were 5.0, 2.0, 10.0 ng/mL and 20.0, 5.0, 50.0 ng/mL, respectively, and their calibration curves were linear over the concentration range 50–400, 20–120 and 150–24000 ng/mL, respectively. The results provided a firm basis for further evaluating the pharmacokinetics and clinical efficacy of NANI. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
100.
The reaction of hydroxylamine hydrochloride with ethyl 3‐aroyl‐1‐cyano‐4‐hydroxy‐2,4,6‐triarylcyclohexanecarboxylate has led to the formation of ethyl 2‐[amino(hydroxyimino)methyl]‐3‐aryl‐5‐(hydroxyimino)‐5‐arylpentanoate via a tandem ring opening and oximation process. The structures of the products are confirmed by NMR and X‐ray techniques, and the conformational features of the product arrived at are compared with a molecular dynamics simulation study. 相似文献