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151.
The crystallization behaviour of as-prepared and nucleated Ge17Sb23Se60 thin films was studied by means of differential scanning calorimetry, X-ray diffraction analysis and scanning electron microscopy. Detailed analysis of the non-isothermal crystal growth kinetics was performed; the apparent activation energy, kinetic model and value of the pre-exponential factor were determined. The kinetic behaviour was found to be surprisingly close to the ideal Johnson–Mehl–Avrami nucleation-growth process, with the only non-ideality being the prolonged peak end tail (which may be a specificity associated with certain thicknesses of thin layers). This corresponds to the initiation of crystal growth in agreement with the classical nucleation theory, with the amount of mechanical defects and strains being negligible. The value of the kinetic parameter suggests two-dimensional crystal growth, which is consistent with the idea of macroscopic crystallites growing in a sterically restricted thin layer. A similar conclusion can be made on the basis of direct microscopic observation of the crystallites’ morphology. 相似文献
152.
We analyze the on-line dimension of partially ordered sets as a value of a two-person game between Algorithm and Spoiler. The game is played in rounds. Spoiler presents an on-line order of width at most w, one point at a time. Algorithm maintains its realizer, i.e., the set of d linear extensions which intersect to the presented order. Algorithm may not change the ordering of the previously introduced elements in the existing linear extensions. The value of the game val(w) is the least d such that Algorithm has a strategy against Spoiler presenting any order of width at most w. For interval orders Hopkins showed that val $(w) \leqslant 4w-4$ . We analyze the on-line dimension of semi-orders i.e., interval orders admitting a unit-length representation. For up-growing semi-orders of width w we prove a matching lower and upper bound of w. In the general (not necessarily up-growing) case we provide an upper bound of 2w. 相似文献
153.
154.
Simon Smolders Tom Willhammar Andra Krajnc Kadir Sentosun Michael T. Wharmby Kirill A. Lomachenko Sara Bals Gregor Mali Maarten B. J. Roeffaers Dirk E. DeVos Bart Bueken 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(27):9258-9263
While titanium‐based metal–organic frameworks (MOFs) have been widely studied for their (photo)catalytic potential, only a few TiIV MOFs have been reported owing to the high reactivity of the employed titanium precursors. The synthesis of COK‐47 is now presented, the first Ti carboxylate MOF based on sheets of TiIVO6 octahedra, which can be synthesized with a range of different linkers. COK‐47 can be synthesized as an inherently defective nanoparticulate material, rendering it a highly efficient catalyst for the oxidation of thiophenes. Its structure was determined by continuous rotation electron diffraction and studied in depth by X‐ray total scattering, EXAFS, and solid‐state NMR. Furthermore, its photoactivity was investigated by electron paramagnetic resonance and demonstrated by catalytic photodegradation of rhodamine 6G. 相似文献
155.
Zhiyue Zhang Hui Li Sabah Kasmi Simon VanHerck Kim Deswarte Bart N. Lambrecht Richard Hoogenboom Lutz Nuhn Bruno G. DeGeest 《Angewandte Chemie (International ed. in English)》2019,58(23):7866-7872
Interactive materials that can respond to a trigger by changing their morphology, but that can also gradually degrade into a fully soluble state, are attractive building blocks for the next generation of biomaterials. Herein, we design such transiently responsive polymers that exhibit UCST behaviour while gradually losing this property in response to a hydrolysis reaction in the polymer side chains. The polymers operate within a physiologically relevant window in terms of temperature, pH, and ionic strength. Whereas such behaviour has been reported earlier for LCST systems, it is at present unexplored for UCST polymers. Furthermore, we demonstrate that, in contrast to LCST polymers, in aqueous medium the UCST polymer forms a coacervate phase below the UCST, which can entrap a hydrophilic model protein, as well as a hydrophobic dye. Because of their non‐toxicity, we also provide in vivo proof of concept of the use of this coacervate as a protein depot, in view of sustained‐release applications. 相似文献
156.
Diederik Aerts Bart D’Hooghe Andrzej Posiewnik Jaroslaw Pykacz Jeroen Dehaene Bart De Moor 《International Journal of Theoretical Physics》2008,47(1):61-68
We show that it is possible to play ‘restricted’ two-player quantum games proposed originally by Marinatto and Weber (Phys.
Lett. A 272:291–303, 2000) by purely macroscopic means, in the simplest case having as the only equipment a pack of 10 cards. Our example shows also
that some apparently ‘genuine quantum’ results, even those that emerge as a consequence of dealing with entangled states,
can be obtained by suitable application of Kolmogorovian probability calculus and secondary-school mathematics, without application
of the ‘Hilbert space machinery’. 相似文献
157.
We present a linear-optical implementation of a class of two-qubit partial SWAP gates for polarization states of photons. Different gate operations, including the SWAP and entangling sqrt[SWAP], can be obtained by changing a classical control parameter, namely, the path difference in the interferometer. Reconstruction of output states, full quantum process tomography, and an evaluation of entanglement of formation prove very good performance of the gates. 相似文献
158.
159.
Kylie B. Manning Alexander G. Shtukenberg Shane M. Nichols Bart Kahr Marcus Weck 《Journal of polymer science. Part A, Polymer chemistry》2015,53(22):2563-2568
N‐(Bis(4‐(2‐ethylhexyloxy)phenyl)(phenyl)‐methyl)methacrylamide was synthesized and polymerized via reversible addition‐fragmentation chain‐transfer (RAFT) polymerization. The chain‐transfer agent (4‐cyano‐4‐(phenylcarbonothioylthio) pentanoic acid (CPADB)), combined with a chiral additive, and a radical initiator yielded polymers with dispersities between 1.2 and 1.4. At low concentrations, the polymers are soluble in hexanes and chloroform while at higher concentrations they swell in these solvents. Characterization of the polymers by wide‐angle X‐ray scattering (WAXS) revealed an interplanar distance of 19.0 Å. The WAXS data combined with polarized optical microscopy support a lamellar crystallization and lyotropic liquid crystalline behavior in hexanes and chloroform. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2563–2568 相似文献
160.
Journal of Statistical Physics - We consider the symmetric exclusion process on suitable random grids that approximate a compact Riemannian manifold. We prove that a class of random walks on these... 相似文献