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991.
de Melo Anely Maciel Barbi Rafaela Cristina Turola Costa Bruno Patrício Ikeda Mônica Alves Fillemon Edillyn Silva Bambirra Carpiné Danielle Ribani Rosemary Hoffmann 《Journal of Thermal Analysis and Calorimetry》2022,147(22):12313-12328
Journal of Thermal Analysis and Calorimetry - Despite their being rich in bioactive compounds, by-products produced during fruit pulping are usually discarded. The present paper aimed to... 相似文献
992.
Giuseppe Bruno Archimede Rotondo Giovanni Grassi Francesco Foti Francesco Risitano Francesco Nicol 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(7):o496-o497
The title compound, C18H15BrN2O5, a promising N‐protected α‐amino acid, was synthesized directly from an unusual bromo dipole and a 4‐(arylmethylene)oxazolone. The crystal packing of the title compound is a racemic mixture. Peculiar graph‐set motifs driven by the most important hydrogen bonds are described. 相似文献
993.
994.
Catherine Bianchi Bruno Grassl Bernard Franois Christine Dagron‐Lartigau 《Journal of polymer science. Part A, Polymer chemistry》2005,43(19):4337-4350
Water‐soluble and photoluminescent block copolymers [poly(ethylene oxide)‐block‐poly(p‐phenylene vinylene) (PEO‐b‐PPV)] were synthesized, in two steps, by the addition of α‐halo‐α′‐alkylsulfinyl‐p‐xylene from activated poly(ethylene oxide) (PEO) chains in tetrahydrofuran at 25 °C. This copolymerization, which was derived from the Vanderzande poly(p‐phenylene vinylene) (PPV) synthesis, led to partly converted PEO‐b‐PPV block copolymers mixed with unreacted PEO chains. The yield, length, and composition of these added sequences depended on the experimental conditions, namely, the order of reagent addition, the nature of the monomers, and the addition of an extra base. The addition of lithium tert‐butoxide increased the length of the PPV precursor sequence and reduced spontaneous conversion. The conversion into PPV could be achieved in a second step by a thermal treatment. A spectral analysis of the reactive medium and the composition of the resulting polymers revealed new evidence for an anionic mechanism of the copolymerization process under our experimental conditions. Moreover, the photoluminescence yields were strongly dependant on the conjugation length and on the solvent, with a maximum (70%) in tetrahydrofuran and a minimum (<1%) in water. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4337–4350, 2005 相似文献
995.
Two basic motivations for an upgraded JLab facility are the needs: to determine the essential nature of light-quark confinement and dynamical chiral symmetry breaking (DCSB); and to understand nucleon structure and spectroscopy in terms of QCD's elementary degrees of freedom. During the next ten years a programme of experiment and theory will be conducted that can address these questions. We present a Dyson-Schwinger equation perspective on this effort with numerous illustrations, amongst them: an interpretation of string-breaking; a symmetry-preserving truncation for mesons; the nucleon's strangeness σ-term; and the neutron's charge distribution. 相似文献
996.
Bruno Grignard Christine Jérôme Cédric Calberg Christophe Detrembleur Robert Jérôme 《Journal of polymer science. Part A, Polymer chemistry》2007,45(8):1499-1506
1H,1H,2H,2H‐Heptadecafluorodecyl acrylate (AC8) was polymerized by reversible addition–fragmentation chain transfer and copolymerized with 2‐hydroxyethyl acrylate with the formation of random and block copolymers, respectively. The kinetics of the (co)polymerization was monitored with 1H NMR spectroscopy and showed that the homopolymerization and random copolymerization of AC8 were under control. As a result of this control and the use of S‐1‐dodecyl‐S‐(α,α′‐dimethyl‐α″‐acetic acid)trithiocarbonate as a chain‐transfer agent, the copolymer chains were end‐capped by an α‐carboxylic acid group. Moreover, the controlled polymerization of AC8 was confirmed by the successful synthesis of poly(1H,1H,2H,2H‐heptadecafluorodecyl acrylate)‐b‐poly(2‐hydroxyethyl acrylate) diblock copolymers, which were typically amphiphilic compounds. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1499–1506, 2007 相似文献
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998.
999.
Bruno de Andrade 《Applied mathematics and computation》2009,215(8):2843-2849
In this work we study the existence and uniqueness of compact almost automorphic solutions to a first-order differential equation with a linear part dominated by a Hille-Yosida type operator with non dense domain. 相似文献
1000.
Irma Lavagnini Bruno Fedrizzi Giuseppe Versini Franco Magno 《Rapid communications in mass spectrometry : RCM》2009,23(8):1167-1172
The effectiveness of isotopically and non‐isotopically labelled internal standards in reducing matrix‐induced effects is evaluated. The question is addressed in the quantitative analysis by gas chromatography/mass spectrometry (GC/MS) of dimethyl sulphide, chosen as a typical example of volatile sulphur compounds, in wine matrices. When matrix/run effects are not cancelled out the use of a variance component model (VCM) to handle the linear calibrations obtained by regression technique is successful. The method implies the estimation of an overall calibration straight line, which properly takes into account the uncertainty due to different matrices, the calibration run and the measurement error, making the use of an isotopically labelled internal standard not necessary. The obtained results show that the benefits of lowering times and costs for routine analyses compensate for the small increase in uncertainty in the concentration values obtained in the regression analysis and the slight increase in the detection limit. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献