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1.
A time discrete scheme is used to approximate the solution toa phase field system of PenroseFife type with a non-conservedorder parameter. An a posteriori error estimate is presentedthat allows the estimation of the difference between continuousand semidiscrete solutions by quantities that can be calculatedfrom the approximation and given data. 相似文献
2.
Olaf von Grudzinski 《manuscripta mathematica》1977,20(3):263-276
Fundamental solutions in a space D(Mp) of Roumieu ultradistributions are constructed for convolutors f whose Fourier transform
is slowly decreasing. The solutions are of exponential growth if
satisfies a stronger condition. These results include a constructive proof of the known existence theorem of Chou. For families of convolutors our method yields solutions which depend continuously on parameters. 相似文献
3.
Paloma Sevillano Sven Koenig Daniel Himmel Olaf Fuhr Dieter Fenske 《无机化学与普通化学杂志》2005,631(11):2236-2240
The reactions of [Co2(CO)8] with E(SiMe3)2 (E = Se, Te) in CH2Cl2 result in the formation of the compounds [Co4Se2(CO)10]> ( 1 ) and [Co4Te2(CO)11] ( 2 ), respectively. Both cluster complexes have similar molecular structures in which the cobalt atoms form four‐membered rings with μ4‐bridging chalcogen atoms (Se and Te) above and below the plane of the metal atoms and the carbonyl ligands as either terminal or μ2‐bridging ligands. DFT‐calculations for both compounds have been carried out in order to obtain some more information about their electronic distribution. In the presence of the phosphine Ph2PC≡CPPh2 (dppa), the reaction of [Co2(CO)8] with Se(SiMe3)2 leads to the formation of [Co8Se4(CO)16(μ‐dppa)2] ( 3 ). During the reaction two molecules of [Co2(CO)8] have been added to the acetylene groups of the dppa ligands, whilst the remaining cobalt atoms coordinate to the phosphorus atoms of the phosphine. In this compounds the selenium atoms act as μ3‐ligands, bridging the metal atoms bonded to the phosphorus with those bonded to the acetylene groups. 相似文献
4.
An explicit derivation of dispersion relations and spectra for periodic Schrödinger operators on carbon nano-structures (including graphene and all types of single-wall nano-tubes) is provided. 相似文献
5.
We subject the baby Skyrme model to a Moyal deformation, for unitary or Grassmannian target spaces and without a potential term. In the Abelian case, the radial BPS configurations of the ordinary noncommutative sigma model also solve the baby Skyrme equation of motion. This gives a class of exact analytic noncommutative baby Skyrmions, which have a singular commutative limit but are stable against scaling due to the noncommutativity. We compute their energies, investigate their stability and determine the asymptotic two-Skyrmion interaction. 相似文献
6.
The design of synthetic agents to disrupt protein-protein interactions has received relatively little attention in recent years. In this review we describe strategies for targeting different types of protein surfaces using mimetics of protein secondary or tertiary structure. In this way strong and selective binding to a protein surface has be achieved and disruption of clinically important protein-protein interactions has been demonstrated in models of human disease. 相似文献
7.
8.
We demonstrate the controlled coherent transport and splitting of atomic wave packets in spin-dependent optical lattice potentials. Such experiments open intriguing possibilities for quantum state engineering of many body states. After first preparing localized atomic wave functions in an optical lattice through a Mott insulating phase, we place each atom in a superposition of two internal spin states. Then state selective optical potentials are used to split the wave function of a single atom and transport the corresponding wave packets in two opposite directions. Coherence between the wave packets of an atom delocalized over up to seven lattice sites is demonstrated. 相似文献
9.
Rakesh Sohal Grzegorz Lupina Olaf Seifarth Peter Zaumseil Christian Walczyk Thomas Schroeder 《Surface science》2010,604(3-4):276-282
Process compatible high-k dielectric thin films are one of the key solutions to develop high performance metal–insulator–metal (MIM) structures for future microelectronic devices. Engineered cerium–aluminate (CexAl2–xO3) thin films were deposited on titanium nitride metal electrodes by electron-beam co-evaporation of ceria and alumina in a molecular beam deposition chamber. X-ray photoelectron spectroscopy clearly reveals that Ce cations can be stabilized in the 3+ valence state in CexAl2–xO3 up to x = 0.7 by accommodation in the alumina host matrix. Higher Ce content was observed to result in cerium dioxide segregation in cerium aluminate matrix, probably due to the chemical tendency of Ce cations to exist rather in the 4+ than in the 3+ state. Electrical characterization of the X-ray amorphous Ce0.7Al1.3O3 films reveals a dielectric constant value of about 11 and leakage current lower than 10?4 A/cm2. No parasitic low-k interface formation between the high-k Ce0.7Al1.3O3 film and the TiN metal electrode is detected. 相似文献
10.
This work compares the behavior of a Giesekus and Carreau-Yasuda fluid in a squeeze flow between two circular plates. In order to do this the Carreau-Yasuda model is fitted to the shear viscosity curve of the Giesekus model and the squeeze stress is compared over the process time. The investigations are performed numerically with a 2.5 dimensional wedge model. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献