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201.
202.
Lectin affinity chromatography as a tool to differentiate endogenous and recombinant erythropoietins
This work exploits the combination of the lectin affinity chromatography (LAC) with an ultra-sensitive immunochromatographic assay to differentiate several types of erythropoietin (EPO). The chromatographic behaviours of different commercial types of recombinant human EPO (rhEPO), EPO analogues (Aranesp) and urine human EPO (uhEPO) from healthy individuals on eight lectin-Sepharose columns, have been worked out. Results show that when using wheat germ agglutinin (WGA)-Sepharose columns, a careful desorption regime starting with very low concentration (2mM) of the competitive sugar N-acetylglucosamine (GlcNAc) makes it possible to efficiently distinguish endogenous EPO from recombinant EPO and EPO analogues. 相似文献
203.
Serena Coiai Elisa Passaglia Francesco Ciardelli Diego Tirelli Franco Peruzzotti Emiliano Resmini 《Macromolecular Symposia》2006,234(1):193-202
The synthesis of polystyrene chains covalently bound to the surface of cross-linked rubber particles from recycled tires (ground tire rubber, GTR) was investigated via free radical polymerization in situ by using azobisisobutyronitrile (AIBN) and dibenzoyl peroxide (BPO) as initiators. Indeed, the graft polymerization provides a significant route to modify the physical and chemical properties of these particles allowing to improve their compatibility with other polymers. Polymerization reactions were carried out in bulk by changing the styrene/GTR ratio as well as the amount of free radical initiator. Appreciable amounts of polystyrene (PS) were grafted on GTR when BPO was used as confirmed by particle characterizations. 相似文献
204.
Dr. Paula Morales Dr. Gemma Navarro Marc Gómez-Autet Laura Redondo Prof. Dr. Javier Fernández-Ruiz Dr. Laura Pérez-Benito Dr. Arnau Cordomí Prof. Dr. Leonardo Pardo Prof. Dr. Rafael Franco Dr. Nadine Jagerovic 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(68):15839-15842
Single chemical entities with potential to simultaneously interact with two binding sites are emerging strategies in medicinal chemistry. We have designed, synthesized and functionally characterized the first bitopic ligands for the CB2 receptor. These compounds selectively target CB2 versus CB1 receptors. Their binding mode was studied by molecular dynamic simulations and site-directed mutagenesis. 相似文献
205.
Pedro Henrique Cavalcanti Franco Saulo Fehelberg Pinto Braga Renata Barbosa de Oliveira Isabela Costa César 《Magnetic resonance in chemistry : MRC》2020,58(1):97-105
Quantitative nuclear magnetic resonance (qNMR) is an analytical technique that offers numerous advantages in pharmaceutical applications including minimum sample preparation and rapid data collection times with no need for response factor corrections, being a powerful tool for assaying drug content in both drug discovery and early drug development. In the present work, we have applied qNMR, using both the internal standard and the electronic reference to access in vivo concentrations 2 calibration methods, to assess the purity of RI76, a novel antifungal drug candidate. NMR acquisition and processing parameters were optimized in order to obtain spectra with intense, well-resolved signals of completely relaxed nuclei. The analytical method was validated following current guidelines, demonstrating selectivity, linearity, accuracy, precision, and robustness. The calibration approaches were statistically compared, and no significant difference was observed when comparing the obtained results and their dispersion in terms of relative standard deviation. The proposed qNMR method may, therefore, be used for both qualitative and quantitative assessments of RI76 in early drug development and for characterization of this compound. 相似文献
206.
Franco Bellesia Franco Ghelfi Romano Grandi Ugo Maria Pagnoni Adriano Pinetti 《Journal of heterocyclic chemistry》1993,30(3):617-621
Pyrroles are powerful nucleophiles in the reaction with dialkyl sulfoxides and trimethylchlorosilane (TMCS) or trimethylbromosilane (TMBS), affording sulfonium salts or halo derivatives, generally in good yields. 相似文献
207.
The anisotropic elastic constants of crystalline octacyclopentyl polyhedral oligomeric silsesquioxane (CpPOSS) were determined using molecular dynamics. The force field used for these calculations was shown to model accurately the rhombohedral and triclinic crystal structures of octasilsesquioxane and CpPOSS, respectively, as well as the vibrational frequencies of octasilsesquioxane. The moduli for CpPOSS are anisotropic, with a Reuss-averaged bulk modulus of 7.5 GPa, an isotropic averaged Young's modulus of 11.78 GPa, and an isotropic averaged shear modulus of 4.75 GPa. These isotropic averages or, alternatively, the full anisotropic stiffness tensor of the crystal can be used with micromechanical composite models to calculate the effective elastic properties of polymer nanocomposites that contain crystalline aggregates of CpPOSS. 相似文献
208.
Collision induced (CI) processes involving hydrogen atoms on a graphite surface are studied quantum mechanically within the rigid, flat surface approximation, using a time-dependent wave packet method. The Eley-Rideal (ER) reaction and collision induced desorption (CID) cross sections are obtained with the help of two propagations which use different sets of coordinates, a "product" and a "reagent" set. Several adsorbate-substrate initial states of the target H atom in the chemisorption well are considered, and CI processes are studied over a wide range of projectile energy. Results show that (i) the Eley-Rideal reaction is the major reactive outcome and (ii) CID cross sections do not exceed 4 A2 and present dynamic thresholds for low values of the target vibrational quantum number. ER cross sections show oscillations at high energies which cannot be reproduced by classical and quasiclassical trajectory calculations. They are related to the vibrational excitation of the reaction products, which is a rather steep decreasing function of the collision energy. This behavior causes a selective population of the low-lying vibrational states and allows the quantization of the product molecular states to manifest itself in a collisional observable. A peak structure in the CID cross section is also observed and is assigned to the selective population of metastable states of the transient molecular hydrogen. 相似文献
209.
Cristina Rota Lino Liverani Franco Spelta Giuseppe Mascellani Aldo Tomasi Anna Iannone 《Research on Chemical Intermediates》2006,32(1):73-81
The use of low-molecular-weight heparins (LMWHs) has become common, since compared to unfractionated heparin (UFH), they have
a much longer plasma half-life and lower incidence of side effects. LMWHs are derived from the depolymerization of UFH, obtained
either chemically, physically or enzymatically. We employed electron spin resonance (ESR) spectroscopy to study the depolymerization
of UFH by copper in the presence of hydrogen peroxide. A stable nitroxide radical was detected. This could be generated by
the hydroxyl radical attack either to the N-SO−3 group or to free amino groups present in the UFH preparation. 相似文献
210.