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31.
4‐Amino‐1‐(2‐deoxy‐β‐D‐ribofuranosyl)quinazolin‐2‐one (4) was prepared by Barton deoxygenation from 4‐amino‐1‐(β‐D‐ribofuranosyl)quinazolin‐2‐one (3) as a 2′‐deoxycytidine analog. 相似文献
32.
33.
Mukund K. Gurjar Yakambram Pedduri C.V. Ramana Vedavati G. Puranik Rajesh G. Gonnade 《Tetrahedron letters》2004,45(2):387-390
Dihydroxylation of the glucose derived α,β-unsaturated lactones 6 and 13 was found to be on the α-face of the pyranolactone ring exclusively. The resulting dihydroxylated compound from 13 has been used in a synthesis of the lactone 4, which corresponds to C(1)-C(11) of peloruside A. 相似文献
34.
《化学:亚洲杂志》2017,12(9):973-977
Graphene quantum dots were covalently crosslinked forming ensembles of a few hundred nanometers in size by McMurry deoxygenation coupling reactions of peripheral carbonyl functional moieties catalyzed by TiCl4 and Zn powders in refluxing THF, as evidenced by TEM, AFM, FTIR, Raman and XPS measurements. Photoluminescence measurements showed that after chemical coupling, the excitation and emission peaks blue‐shifted somewhat and the emission intensity increased markedly, likely due to the removal of oxygenated species where quinone‐like species are known to be effective electron acceptors and emission quenchers. 相似文献
35.
Daniel B. Larsen Dr. Allan R. Petersen Dr. Johannes R. Dethlefsen Dr. Ayele Teshome Dr. Peter Fristrup 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(46):16621-16631
The molybdate‐catalysed transfer hydrodeoxygenation (HDO) of benzyl alcohol to toluene driven by oxidation of the solvent isopropyl alcohol to acetone has been investigated by using a combination of experimental and computational methods. A Hammett study that compared the relative rates for the transfer HDO of five para‐substituted benzylic alcohols was carried out. Density‐functional theory (DFT) calculations suggest a transition state with significant loss of aromaticity contributes to the lack of linearity observed in the Hammett study. The transfer HDO could also be carried out in neat PhCH2OH at 175 °C. Under these conditions, PhCH2OH underwent disproportionation to yield benzaldehyde, toluene, and significant amounts of bibenzyl. Isotopic‐labelling experiments (using PhCH2OD and PhCD2OH) showed that incorporation of deuterium into the resultant toluene originated from the α position of benzyl alcohol, which is in line with the mechanism suggested by the DFT study. 相似文献
36.
It has been demonstrated that dialkyl, diaryl, and aryl alkyl sulfoxides can be efficiently converted into the corresponding sulfides by the reaction with a MoCl5/In system in good to excellent yields under mild conditions. 相似文献
37.
A new solid supported reagent, silica–PSCl3, has been developed for deoxygenation of sulfoxides. With this reagent, conversion of sulfoxides to sulfides occurred cleanly and efficiently at room temperature. Facile isolation of the product was achieved by simple filtration of the by‐products without any extensive workup. 相似文献
38.
E. N. Guryanova L. A. Ganushin I. P. Romm 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):117-118
Abstract The structure and the coordination properties of sulfur compounds such as RS-(CH2)n-SR, (I), n=1-10 and RS-(CH2)nCOOR' (II), n=1,2 have been investigated by dipole moment, calorimetrie, IR-spectroscopy and cryoscopy methods. 相似文献
39.
Vadim Yu. Kukushkin Elena A. Aleksandrova Boris V. Zhadanov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):433-435
Abstract The interaction of the complexes (Et4 N)[Pt(R2 SO)X3] (R = Me, Et, CH2 Ph, X [dbnd] C1; R [dbnd] Me, X [dbnd] Br) and cis-[Pt(Me2 SO)2 Cl2] with concentrated HX (X [dbnd] Cl. Br) results in the reduction of the coordinated sulfoxides and oxidation of Pt(II) to Pt(IV). As a result [Pt(R2 S)X5 and [Pt(R2S)2 X4] are formed. Ligands R2 S can be removed from the complexes and isolated in a free state. 相似文献
40.
H. D. Durst D. K. Rohrbaugh S. Munavalli 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2680-2696
Microwave-assisted reaction of dimethyl H-phosphonate with cyclohexene-, 1,2-butene-, and 1,2-decene oxides furnishes 8, 5, and 17 compounds, respectively. The probable mechanism of the formation of the various compounds via free radical reactions and their GC-MS characterization are presented in this article. 相似文献