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71.
Ludwig Maier 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):465-470
Abstract N,N-Disubstituted formamides such as dimethylformamide. N-formylpyrrolidine, N-formylpiperidine etc. and also pyridine and hexamethylphosphonic acid triamide catalyze the chlorination of phosphonates with thionyl chloride to give phosphonyl dichlorides in high yield. Thus RP(O)CI2, R ? CH3, C2H5, n-C12H25, C6H5, have been isolated in better than 90 per cent yield. The procedure is less satisfactory for the production of 2-chloroethylphosphonyl dichloride. Only a 34 per cent yield was realized. The chlorination proceeds very likely through the intermediate formation of the halfesters, RP(O)(OR)CI since these could be isolated under favorable circumstances. 相似文献
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Vasylyev MV Wachtel EJ Popovitz-Biro R Neumann R 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(13):3507-3514
An organic-inorganic hybrid material, TPPhA-Ti, was constructed by non-hydrolytic condensation of a dendritic tetrakis-1,3,5,7-(4-phosphonatophenyl)adamantane precursor and titanium(IV) isopropoxide. One preparative pathway yielded insoluble materials with a Ti/P ratio of approximately 1 which was confirmed by a combination of FT-IR, TGA, and EDS measurements. N2 sorption experiments showed that TPPhA-Ti is a porous solid (micropores approximately 13 A; mesopores approximately 38 A) with a high surface area, approximately 550 m2 g(-1). The structure and morphology of the TPPhA-Ti as investigated by transmission and scanning electron microscopy showed a layered-type material. Additional X-ray diffraction data suggest a paracrystalline material; an optimization of possible molecular arrangements of TPPhA-Ti was simulated that was in agreement with the experimental data. A second preparative pathway yielded a Ti oxide-phosphonate with a Ti/P ratio of approximately 3.4. Both TEM and SEM revealed that hollow nanospheres were formed with diameters of approximately 180-300 nm. 相似文献
75.
Four new SnII phosphonates have been synthesized by hydrothermal methods, and their structures determined by single-crystal X-ray diffraction. Tin(II) 3-pyridylphosphonate, SnO3PC5H4N (I), crystallizes in P21/c with a=4.9595(8) Å, b=10.7673(18) Å, c=13.996(2) Å, and β=93.616(2)°. Tri-tin(II) (μ-3)-oxo-(bis)-4-pyridylphosphonate, Sn3O(O3PC5H4N)2 (II), crystallizes in P-1 with a=7.2406(14) Å, b=9.9524(19) Å, c=12.604(3) Å, α=104.510(11)°, β=90.326(11)°, and γ=110.897(11)°. Tin(II) 6-methyl-2-pyridylphosphonate quadrahydrate, Sn(O3PC5H3NCH3)·0.25H2O (III), crystallizes in Pna21, a=18.955(3) Å, b=9.7543(14) Å, and c=17.833(3) Å. Tin(II) 4-cyanophenylphosphonate, Sn(O3PC6H4CN) (IV), crystallizes in P-1, a=5.0019(3) Å, b=8.4396(5) Å, c=10.3099(6) Å, α=90.352(3)°, β=94.894(3)°, and γ=92.236(4)°. I, II, and IV have ladder-type structures, and III is a layered compound. The structural variations show the effects of the Sn-N interaction on the final structures. 相似文献
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在室温下,二氟溴甲基膦酸二乙酯与锌粉反应生成锌试剂;2,4-二硝基氯化苄与合成的锌试剂在溴化亚铜催化作用下即可反应生成二硝基苯乙基(氟代)磷酸二乙酯化合物。两步反应都可在室温下进行,操作简单易行。 相似文献
78.
A. N. Pudovik R. R. Shagidullin V. K. Khairullin I. I. Vandyukova A. V. Chernova M. A. Pudovik 《Russian Chemical Bulletin》1996,45(5):1240-1242
Abstact Interaction of ethylN,N-(p-methoxybenzal)-p-aminobenzoate with dialkyl phosphonates results in dialkyl (N-p-ethoxycarbonylphenylamino)-p-methoxybenzal phosphonates. In the resulting compounds hydrogen bonds are observed by IR spectroscopy.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1301–1303, May, 1996. 相似文献
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Synthesis of Unprecedented Sulfonylated Phosphono‐exo‐Glycals Designed as Inhibitors of the Three Mycobacterial Galactofuranose Processing Enzymes 下载免费PDF全文
Christophe J.‐M. Frédéric Dr. Abdellatif Tikad Jian Fu Dr. Weidong Pan Ruixiang B. Zheng Dr. Akihiko Koizumi Dr. Xiaochao Xue Prof. Todd L. Lowary Prof. Stéphane P. Vincent 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(44):15913-15920
This study reports a new methodology to synthesize exo‐glycals bearing both a sulfone and a phosphonate. This synthetic strategy provides a way to generate exo‐glycals displaying two electron‐withdrawing groups and was applied to eight different carbohydrates from the furanose and pyranose series. The Z/E configurations of these tetrasubstituted enol ethers could be ascertained using NMR spectroscopic techniques. Deprotection of an exo‐glycal followed by an UMP (uridine monophosphate) coupling generated two new UDP (uridine diphosphate)‐galactofuranose analogues. These two Z/E isomers were evaluated as inhibitors of UGM, GlfT1, and GlfT2, the three mycobacterial galactofuranose processing enzymes. Molecule 46‐(E) is the first characterized inhibitor of GlfT1 reported to date and was also found to efficiently inhibit UGM in a reversible manner. Interestingly, GlfT2 showed a better affinity for the (Z) isomer. The three enzymes studied in the present work are not only interesting because, mechanistically, they are still the topic of intense investigations, but also because they constitute very important targets for the development of novel antimycobacterial agents. 相似文献