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71.
Serpe A Bigoli F Cabras MC Fornasiero P Graziani M Mercuri ML Montini T Pilia L Trogu EF Deplano P 《Chemical communications (Cambridge, England)》2005,(8):1040-1042
We describe here an innovative method for Pd-dissolution using the reagent N,N'-dimethylperhydrodiazepine-2,3-dithione diiodine adduct which, being safe and powerful, is appealing for practical applications: remarkably almost quantitative Pd-recovery from model spent three-way catalysts has been obtained, showing that the effectiveness of the method is maintained when palladium is contained in a complex system such as a car catalyst, a ceramic material which has undergone severe thermal stress. 相似文献
72.
Proton magnetic resonance chemical shifts and coupling constants for some 5-substituted dihydrofurans, dihydrofuran and dihydrothiophene fused rings are reported, the substituents being methyl, ethyl and phenyl. The observed coupling constants are consistent with buckled rings, in which it appears that a conformation with pseudo-equatorial substituents is predominant. 相似文献
73.
Claudio Emanuele Latagliata Enrico Patrono Stefano Puglisi-Allegra Rossella Ventura 《BMC neuroscience》2010,11(1):15
Background
Eating disorders are multifactorial psychiatric disorders. Chronic stressful experiences and caloric restriction are the most powerful triggers of eating disorders in human and animals. Although compulsive behavior is considered to characterize pathological excessive food intake, to our knowledge, no evidence has been reported of continued food seeking/intake despite its possible harmful consequences, an index of compulsive behavior. Brain monoamine transmission is considered to have a key role in vulnerability to eating disorders, and norepinephrine in medial prefrontal cortex has been shown to be critical for food-related motivated behavior. 相似文献74.
Michele Miranda Jr. Emanuele Paolini Eugene Stepanov 《Calculus of Variations and Partial Differential Equations》2006,27(3):287-309
Consider the class of closed connected sets satisfying length constraint with given l>0. The paper is concerned with the properties of minimizers of the uniform distance F
M of Σ to a given compact set ,
where dist(y, Σ) stands for the distance between y and Σ. The paper deals with the planar case n=2. In this case it is proven that the minimizers (apart trivial cases) cannot contain closed loops. Further, some mild regularity properties as well as structure of minimizers is studied. 相似文献
(22) |
75.
Pietro Baldi Emanuele Haus Riccardo Montalto 《Journal of Differential Equations》2018,264(3):1786-1840
We prove internal controllability in arbitrary time, for small data, for quasi-linear Hamiltonian NLS equations on the circle. We use a procedure of reduction to constant coefficients up to order zero and HUM method to prove the controllability of the linearized problem. Then we apply a Nash–Moser–Hörmander implicit function theorem as a black box. 相似文献
76.
Emanuele Nunzio Spadaro 《manuscripta mathematica》2010,132(3-4):415-429
We provide new elementary proofs of the following two results: every complex variety is locally the graph of a Dir-minimizing function, first proved by Almgren (Almgren’s big regularity paper, volume 1 of World Scientific Monograph Series in Mathematics, 2000); the gradients of Dir-minimizing functions, in principle square-summable, are p-integrable for some p > 2, proved by De Lellis and Spadaro (Higher integrability and approximation of minimal currents, 2009). In the planar case, we prove that our integrability exponents are optimal. 相似文献
77.
Chiara Lavarello Sebastiano Barco Martina Bartolucci Isabella Panfoli Emanuele Magi Gino Tripodi Andrea Petretto Giuliana Cangemi 《Molecules (Basel, Switzerland)》2021,26(14)
Liquid-chromatography coupled to high resolution mass spectrometry (LC-HRMS) is currently the method of choice for untargeted metabolomic analysis. The availability of established protocols to achieve a high confidence identification of metabolites is crucial. The aim of this work is to describe the workflow that we have applied to build an Accurate Mass Retention Time (AMRT) database using a commercial metabolite library of standards. LC-HRMS analysis was carried out using a Vanquish Horizon UHPLC system coupled to a Q-Exactive Plus Hybrid Quadrupole-Orbitrap Mass Spectrometer (Thermo Fisher Scientific, Milan, Italy). The fragmentation spectra, obtained with 12 collision energies, were acquired for each metabolite, in both polarities, through flow injection analysis. Several chromatographic conditions were tested to obtain a protocol that yielded stable retention times. The adopted chromatographic protocol included a gradient separation using a reversed phase (Waters Acquity BEH C18) and a HILIC (Waters Acquity BEH Amide) column. An AMRT database of 518 compounds was obtained and tested on real plasma and urine samples analyzed in data-dependent acquisition mode. Our AMRT library allowed a level 1 identification, according to the Metabolomics Standards Initiative, of 132 and 124 metabolites in human pediatric plasma and urine samples, respectively. This library represents a starting point for future metabolomic studies in pediatric settings. 相似文献
78.
79.
Bernard Dacorogna Paolo Marcellini Emanuele Paolini 《NoDEA : Nonlinear Differential Equations and Applications》2013,20(2):345-359
The two well problem consists in finding maps u which satisfy some boundary conditions and whose gradient Du assumes values in the two wells ${\mathbb{S}_{A}, \mathbb{S}_{B}}$ . Here ${\mathbb{S}_{A}}$ (similarly ${\mathbb{S}_{B}}$ ) is the well generated by a 2 × 2 matrix A, i.e., ${\mathbb{S}_{A}}$ is the set of matrices of the form RA, where R is a rotation. We study specifically the case when at least one of the two matrices A, B is singular and we characterize piecewise affine maps u satisfying almost everywhere the differential inclusion ${Du(x) \in \mathbb{S}_{A} \cup \mathbb{S}_{B}}$ . In particular we describe the lamination and angle properties, which turn out to be different from those of the nonsingular case described in detail in [15]. We also show that the two well problem can be solved in some cases involving singular matrices, in strict contrast to the nonsingular (and not orthogonal) case. 相似文献
80.
Spectroscopic Fourier self-deconvolution analysis was used to investigate β-sheet features in the secondary structure of hemoglobin under mobile phone microwaves at 900 MHz. To this end, four samples of hemoglobin in bidistilled water, sucrose, trehalose, and sodium chloride aqueous solutions were exposed for up to 4 hr to 900 MHz microwaves at an average H-field intensity of 42 mA/m. Quantitative spectral analyses highlighted significant increases in β-sheet contents in the Amide I region of hemoglobin samples in bidistilled water solution, but no appreciable change was observed in hemoglobin samples in sucrose, trehalose, and sodium chloride solutions. These results led us to conclude that mobile phone microwaves can denaturate hemoglobin in bidistilled water solution whereas sucrose, trehalose, and sodium chloride solutions produce a protective effect against microwaves, preserving the protein from unfolding. 相似文献