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161.
A method based on the analytical evaluation of residual unsaturations and on the knowledge of the cyclization ratios is presented for the determination of the cyclopolymer composition in terms of structural units. The application of this method to the products of the free radical polymerization of vinyl-transcrotonate and of divinyl ether is described. 相似文献
162.
Insights into the Halogen Oxidative Addition Reaction to Dinuclear Gold(I) Di(NHC) Complexes
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Dr. Marco Baron Prof. Cristina Tubaro Prof. Marino Basato Prof. Abdirisak Ahmed Isse Prof. Armando Gennaro Prof. Luigi Cavallo Prof. Claudia Graiff Prof. Alessandro Dolmella Dr. Laura Falivene Dr. Lucia Caporaso 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(29):10211-10224
Gold(I) dicarbene complexes [Au2(MeIm‐Y‐ImMe)2](PF6)2 (Y=CH2 ( 1 ), (CH2)2 ( 2 ), (CH2)4 ( 4 ), MeIm=1‐methylimidazol‐2‐ylidene) react with iodine to give the mixed‐valence complex [Au(MeIm‐CH2‐ImMe)2AuI2](PF6)2 ( 1 aI ) and the gold(III) complexes [Au2I4(MeIm‐Y‐ImMe)2](PF6)2 ( 2 cI and 4 cI ). Reaction of complexes 1 and 2 with an excess of ICl allows the isolation of the tetrachloro gold(III) complexes [Au2Cl4(MeIm‐CH2‐ImMe)2](PF6)2 ( 1 cCl ) and [Au2Cl4(MeIm‐(CH2)2‐ImMe)2](Cl)2 ( 2 cCl‐Cl ) (as main product); remarkably in the case of complex 2 , the X‐ray molecular structure of the crystals also shows the presence of I‐Au‐Cl mixed‐sphere coordination. The same type of coordination has been observed in the main product of the reaction of complexes 3 or 4 with ICl. The study of the reactivity towards the oxidative addition of halogens to a large series of dinuclear bis(dicarbene) gold(I) complexes has been extended and reviewed. The complexes react with Cl2, Br2 and I2 to give the successive formation of the mixed‐valence gold(I)/gold(III) n aX and gold(III) n cX (excluding compound 1 cI ) complexes. However, complex 3 affords with Cl2 and Br2 the gold(II) complex 3 bX [Au2X2(MeIm‐(CH2)3‐ImMe)2](PF6)2 (X=Cl, Br), which is the predominant species over compound 3 cX even in the presence of free halogen. The observed different relative stabilities of the oxidised complexes of compounds 1 and 3 have also been confirmed by DFT calculations. 相似文献
163.
I.-G. Marino R. Raschellà P. P. Lottici D. Bersani C. Razzetti A. Lorenzi A. Montenero 《Journal of Sol-Gel Science and Technology》2006,37(3):201-206
Hybrid silica-based sol-gel films containing Disperse Red 1 (DR1), carbazole units (CBZ) and 2,4,7-trinitro-9-fluorenone (TNF)
at different concentrations show reversible photoinduced birefringence. Polarization sensitive holographic gratings have been
produced and characterized. Dichroism measurements give information on the orientation mechanisms and on the aggregation of
the dye molecules. The alignment of the DR1 molecules by corona poling is verified by second harmonic generation (SHG) and
a moving grating technique is used to investigate an asymmetric energy exchange in a two-beam coupling experiment, typical
of photorefractive gratings. 相似文献
164.
Dirhodium(II) perfluorocarboxylates bearing C7–C13 perfluoroalkyl chains have been prepared and used as catalysts under fluorous biphasic conditions. They were found to be active and recyclable catalysts for the silylation of alcohols with triethylsilane. Hydrophobic, primary alcohols are preferentially silylated by the fluorous biphasic catalytic system in comparison with hydrophilic or secondary ones. This opens the way to the development of selective silylation protocols. 相似文献
165.
166.
Dr. Mario Prejanò Dr. Fabiola Estefany Medina Prof. Pedro Alexandrino Fernandes Prof. Nino Russo Prof. Maria Joao Ramos Prof. Tiziana Marino 《Chemphyschem》2019,20(21):2881-2886
We have computationally determined the catalytic mechanism of human transketolase (hTK) using a cluster model approach and density functional theory calculations. We were able to determine all the relevant structures, bringing solid evidences to the proposed experimental mechanism, and to add important detail to the structure of the transition states and the energy profile associated with catalysis. Furthermore, we have established the existence of a crucial intermediate of the catalytic cycle, in agreement with experiments. The calculated data brought new insights to hTK′s catalytic mechanism, providing free-energy values for the chemical reaction, as well as adding atomistic detail to the experimental mechanism. 相似文献
167.
Back Cover: Simultaneous Assessment of Kinetic,Site‐Specific,and Structural Aspects of Enzymatic Protein Phosphorylation (Angew. Chem. Int. Ed. 36/2014) 下载免费PDF全文
168.
Oluwatayo F. Ikotun Nadia Marino Paul E. Kruger Miguel Julve Robert P. Doyle 《Coordination chemistry reviews》2010,254(7-8):890-915
Current attention continues to revolve around the chemistry and biochemistry associated with polyphosphate anions because of their importance in biology. A pivotal intermediate within this family is the pyrophosphate tetraanion, P2O74?. Considering its biological relevance and the multidentate nature that makes it an ideal ligand in the field of the coordination chemistry, there is a growing interest in the use of this anion in building new class of molecules/compounds for different purposes. While the total number of characterized structures still remains modest, several new pyrophosphate-containing coordination complexes have been reported in the last decade, as well as different solid-state structures. This review focuses on the structural, magnetic, and biological properties of coordination complexes incorporating the pyrophosphate ligand reported to date. 相似文献
169.
Prof. Francesco Sannicolò Prof. Patrizia R. Mussini Prof. Tiziana Benincori Prof. Rocco Martinazzo Dr. Serena Arnaboldi Giulio Appoloni Dr. Monica Panigati Dr. Elsa Quartapelle Procopio Valentina Marino Dr. Roberto Cirilli Dr. Simone Casolo Prof. Wlodzimierz Kutner Dr. Krzysztof Noworyta Dr. Agnieszka Pietrzyk‐Le Zofia Iskierko Katarzyna Bartold 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(31):10839-10847
The racemate of an inherently chiral “spider‐like” octathiophene monomer T83 , in which chirality is generated by torsion in its backbone, was synthesized. The racemate was resolved into configurationally stable antipodes by HPLC on a chiral stationary phase. Electrooxidation of the enantiomers resulted in materials displaying high enantiorecognition ability towards the antipodes of some chiral probes. Moreover, the T83 racemate demonstrated great aptitude to stimulate formation of 3D rigid architectures if used as a cross‐linking monomer for molecular imprinting. This feature was exploited to devise a molecularly imprinted polymer‐based chemosensor selective for a thymine–adenine oligonucleotide. 相似文献
170.