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81.
82.
In this work, nanostructured tungsten oxide was electrodeposited by cyclic voltammetric technique onto a stainless steel surface. The structure and surface morphology of the resulting oxide film were characterized by means of X-ray diffraction, scanning probe microscopy, and scanning electron microscopy. The electrochemical intercalation of lithium into the nanostructured tungsten oxide was studied using cyclic voltammetry, galvanostatic charge–discharge curves, and electrochemical impedance spectroscopy in a liquid electrolyte consisting of 1 M LiClO4 in propylene carbonate. The as-deposited tungsten oxide indicated the capacity for electrochemical lithium insertion. The specific capacitance of 108.05 F?g?1 was obtained at the constant discharge density of 0.07 mA?cm?2. 相似文献
83.
Hadis Azin Mohammad Hossein Heydari Fakhrodin Mohammadi 《Mathematical Methods in the Applied Sciences》2022,45(1):411-422
In this paper, the Vieta–Fibonacci wavelets as a new family of orthonormal wavelets are generated. An operational matrix concerning fractional integration of these wavelets is extracted. A numerical scheme is established based on these wavelets and their fractional integral matrix together with the collocation technique to solve fractional pantograph equations. The presented method reduces solving the problem under study into solving a system of algebraic equations. Several examples are provided to show the accuracy of the method. 相似文献
84.
Pedro Larra?aga Hossein Karshenas Concha Bielza Roberto Santana 《Journal of Heuristics》2012,18(5):795-819
Thanks to their inherent properties, probabilistic graphical models are one of the prime candidates for machine learning and decision making tasks especially in uncertain domains. Their capabilities, like representation, inference and learning, if used effectively, can greatly help to build intelligent systems that are able to act accordingly in different problem domains. Evolutionary algorithms is one such discipline that has employed probabilistic graphical models to improve the search for optimal solutions in complex problems. This paper shows how probabilistic graphical models have been used in evolutionary algorithms to improve their performance in solving complex problems. Specifically, we give a survey of probabilistic model building-based evolutionary algorithms, called estimation of distribution algorithms, and compare different methods for probabilistic modeling in these algorithms. 相似文献
85.
In this work, the ability of different types of nanocages including Al12N12, Al12P12, Be12O12, B12N12, Si12C12, Mg12O12 and C24 for the adsorption and detection of poisonous gases HCN and ClCN has been investigated, theoretically using the D3 dispersion corrected density functional theory (DFT-D3). The absorption spectra of HCN–nanocage and ClCN–nanocage complexes were calculated by the time-dependent density functional theory (TD-DFT) and compared with the calculated absorption spectrum of isolated nanocage to investigate the ability of nanocage for sensing of HCN and ClCN gases. It was found that the strongest interaction between HCN (ClCN) molecule and nanocage takes place when the molecule is adsorbed via its N atom on the surface of nanocage except for C24. Also, it was shown that the Al12N12 is the best adsorbent for HCN and ClCN gases among the selected nanocages and Si12C12 is the best sensor for the detection of these gases using the electroconductivity and absorption spectroscopy techniques. 相似文献
86.
ABSTRACTUsing density functional theory calculations, we investigate the gas sensing performance of B-, N-doped and BN-codoped C60 fullerenes towards NO and NO2 molecules. The calculated adsorption energies and net charge-transfer values indicate that NO and NO2 molecules have a stronger interaction with the BN-codoped fullerenes compared to the B- or N-doped ones. It is also found that the electronic properties of the BN-codoped C60 exhibit a larger sensitivity towards NO and NO2 molecules. An increase in the concentration of doped/co-doped B and N atoms tends to weaken the gas sensing ability of these systems. 相似文献
87.
ABSTRACTAn ab initio study, at the MP2/aug-cc-pVTZ level of theory, is performed to study σ-hole bond in binary XH3C···CNY complexes, where X = CN, F, NO2, CCH and Y = H, OH, NH2, CH3, C2H5, Li. This type of interaction is labelled as ‘carbon bond’, since a covalently bonded carbon atom acts as the Lewis acid in these systems. The geometrical and energetic parameters of the resulting complexes are analysed in details. The interaction energies of these complexes are between ?4.97 kJ/mol in (HCC)H3C···CNH and ?23.07 kJ/mol in (O2N)H3C···CNLi. It is found that the electrostatic interaction plays a key role in the overall stabilisation of these carbon-bonded complexes. To deepen the understanding of the nature of the carbon-bonding, the molecular electrostatic potential, natural bond orbital, quantum theory of atoms in molecules and non-covalent interaction index analyses are also used. Our results indicate that the carbon bond is favoured over the C-H···C hydrogen bond in the all complexes considered and may suggest the possible important roles of the C···C interactions in the crystal growth and design. 相似文献
88.
Spherically Symmetric Jordan-Brans-Dicke Quantum Gravity with de Broglie Bohm Pilot Wave Perspective
Hossein Ghaffarnejad 《International Journal of Theoretical Physics》2014,53(8):2616-2622
We obtain two dimensional analogue of the Jordan-Brans-Dicke (JBD) gravity action described in four dimensional spherically symmetric curved space time metric. There will be two scalar fields, namely, the Brans Dicke (BD) ? and scale factor of 2-sphere part of the space time ψ. We obtained suitable duality transformations between (ψ, ?) and (ρ, S) where ρ and S is respectively amplitude and phase part of the corresponding de Broglie pilot wave function \(\Psi (\rho ,S)=\sqrt {\rho }e^{iS}.\) Covariant conservation of mass-energy current density of particles ensemble J a = ρ? a S, is established by applying a particular dynamical conformal frame described by (ρ, S). 相似文献
89.
90.