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91.
Let be a plane graph, and let be a colouring of its edges. The edge colouring of is called facial non-repetitive if for no sequence , , of consecutive edge colours of any facial path we have for all . Assume that each edge of a plane graph is endowed with a list of colours, one of which has to be chosen to colour . The smallest integer such that for every list assignment with minimum list length at least there exists a facial non-repetitive edge colouring of with colours from the associated lists is the facial Thue choice index of , and it is denoted by . In this article we show that for arbitrary plane graphs . Moreover, we give some better bounds for special classes of plane graphs. 相似文献
92.
Ming Sun Alina Stetco Erika F Merschrod S 《Langmuir : the ACS journal of surfaces and colloids》2008,24(10):5418-5421
Ordered arrays of collagen microfibrils form rapidly and spontaneously from a solution of monomers deposited onto a mica substrate. These arrays are well-ordered and apparently continuous over the entire substrate. Correlated atomic force microscope images and Laué diffraction patterns indicate that the protein alignment and microfibril formation is controlled by the crystal orientation of the mica substrate rather than fluid flow or drying effects. This surface-induced mechanism allows for immediate, robust, and reproducible pattern formation. 相似文献
93.
Veronika Nagy Erika Turcsi Péter Molnár Zoltán Szabó József Deli 《Tetrahedron letters》2007,48(51):9012-9014
Latoxanthin was isolated as a minor carotenoid from the ripe fruits of yellow tomato shaped paprika (Capsicum annuum var. lycopersiciforme flavum) and identified as (all-E,3S,5R,6R,3′S,5′R,6′S)-5′,6′-epoxy-5,6,5′,6′-tetrahydro-β,β-carotene-3,5,6,3′-tetrol based on spectral data. 相似文献
94.
Erika Szunyogová Katarína Györyová Daniela Hudecová Lenka Piknová J. Chomič Zuzanna Vargová V. Zeleňák 《Journal of Thermal Analysis and Calorimetry》2007,88(1):219-223
The thermal decomposition of the complexes Zn(form)2⋅2phen
(I), Zn(ac)2⋅2phen
(II), Zn(prop)2⋅2phen
(III), Zn(but)2⋅2phen
(IV), where phen=phenazone, form=formiate,
ac=acetate, prop=propionate, but=butyrate has been studied in air by TG/DTG
and DTA methods. The possible mechanism of the thermal decomposition was proposed.
The final product of thermal decomposition was ZnO. IR data show unidentate
coordination of carboxylate group to Zn(II) ion. The complexes were tested
against various strains of microorganisms and their efficiency decrease in
the sequence yeasts >bacteria>filamentous fungi. 相似文献
95.
96.
Chatterjee D Ember E Pal U Ghosh S van Eldik R 《Dalton transactions (Cambridge, England : 2003)》2011,40(40):10473-10480
The Ru(III)(edta)/H(2)O(2) system (edta(4-) = ethylenediaminetretaacetate) was found to degrade the azo-dye Orange II at remarkably high efficiency under ambient conditions. Catalytic degradation of the dye was studied by using rapid-scan spectrophotometry as a function of [H(2)O(2)], [Orange II] and pH. Spectral analyses and kinetic data point towards a catalytic pathway involving the rapid formation of [Ru(III)(edta)(OOH)](2-) followed by the immediate subsequent degradation of Orange II prior to the conversion of [Ru(III)(edta)(OOH)](2-) to [Ru(IV)(edta)(OH)](-) and [Ru(V)(edta)(O)](-)via homolysis and heterolysis of the O-O bond, respectively. The higher oxidation state Ru(IV) and Ru(V) complexes react three orders of magnitude slower with Orange II than the Ru(III)-hydroperoxo complex. In comparison to biological oxygen transfer reactions, the Ru(edta) complexes show the reactivity order Compound 0 ? Compounds I and II. 相似文献
97.
98.
Recent work has elucidated the potential of important new therapeutic paradigms, including metronomic delivery and chronotherapy, in which the precise timing and location of therapeutic administration has a significant impact on efficacy and toxicity. New drug delivery architectures are needed to not only release drug continuously at precise rates, but also synchronize their release with circadian cycles. We present an actively controlled nanofluidic membrane that exploits electrophoresis to control the magnitude, duration, and timing of drug release. The membrane, produced using high precision silicon fabrication techniques, has platinum electrodes integrated at the inlet and outlet that allow both amplification and reversal of analyte delivery with low applied voltage (at or below 2 VDC). Device operation was demonstrated with solutions of both fluorescein isothiocyanate conjugated bovine serum albumin and lysozyme using fluorescence spectroscopy, fluorescence microscopy, and a lysozyme specific bio-assay and has been characterized for long-term molecular release and release reversibility. Through a combination of theoretical and experimental analysis, the relative contributions of electrophoresis and electroosmosis have been investigated. The membrane's clinically relevant electrophoretic release rate at 2 VDC exceeds the passive release by nearly one order of magnitude, demonstrating the potential to realize the therapeutic paradigm goal. 相似文献
99.
Patricia Garcia-Herrera Helayne A. Maieves Erika N. Vega María Luisa Perez-Rodriguez Virginia Fernandez-Ruiz Amaia Iriondo-DeHond Maria Dolores del Castillo Maria Cortes Sanchez-Mata 《Molecules (Basel, Switzerland)》2022,27(17)
The feasibility of using dwarf kiwi fruits (Actinia arguta Miq.) as a healthy and sustainable food, compared to other types of commercial kiwi fruits, was evaluated in the present study. The overall antioxidant capacity of these fruits was assessed by either extraction-dependent methods (ABTS, ORAC) or the direct method called Quick, Easy, New, CHEap, Reproducible (QUENCHER) (DPPH, FRAP, Folin–Ciocalteu), applied for the first time to analyze kiwi fruits. With this methodology, all the molecules with antioxidant capacity are measured together in a single step, even those with high molecular weight or poor solubility in aqueous extraction systems, such as antioxidant dietary fiber. The effect of kiwi extracts on physiological and induced intracellular reactive oxygen species (ROS) production on IEC-6 cells was also analyzed, as well as total phenolic content (TPC) by Fast Blue BB, flavonols, hydroxycinnamic acids, and hydroxybenzoic acids. A. arguta fruits showed the highest values in all the antioxidant assays, being remarkably higher than the other kiwi species for Q-FRAP and Q-DPPH. Dwarf kiwi showed the highest potential in reducing physiological ROS and the highest values of TPC (54.57 mgGAE/g), being hydroxybenzoic acids the main phenolic family found (2.40 mgGAE/g). Therefore, dwarf kiwi fruits are a natural source of antioxidants compared to conventional kiwi fruits, being a sustainable and healthy alternative to diversify fruits in the diet. 相似文献
100.
Ohne Zusammenfassung 相似文献