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991.
The Banach ultrapower construction is applied in fixed point theory for multivalued mappings. We introduce the notion of ultra-asymptotic centers and use it to remove the separability assumption from the results of Domínguez Benavides, Lorenzo Ramírez (2004) and Dhompongsa, Kaewcharoen, Kaewkhao (2006). 相似文献
992.
A. Wolf G. Uhlenberg U. Schramm T. Schüßler A.E. Livingston G. Gwinner G. Saathoff D. Schwalm 《Hyperfine Interactions》2000,127(1-4):203-210
Spectroscopic results obtained on multiply charged few electron ions by using laser stimulated two-step recombination in ion
storage rings are presented in an overview. Line splittings in transitions between Rydberg levels were observed for helium
like and beryllium like ions. Emphasis is given to results on the beryllium like system N3+ where information about the splitting between high angular momentum levels (l⩾4) was obtained for the Rydberg levels n=13 and 8 with experimental errors of about ±0.02 meV.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
993.
Wolfgang R. Plaß 《Hyperfine Interactions》2006,173(1-3):19-26
An overview of direct mass measurements of exotic nuclei at the FRS-ESR facility at GSI is given. The nuclides are produced
at relativistic energies by projectile fragmentation and fission, separated in-flight at the fragment separator FRS and injected
into the storage ring ESR. Mass measurements are performed using Schottky and Isochronous Mass Spectrometry, which both allow
for high precision measurements with single-ion sensitivity. Recent experimental developments are summarized, and examples
for measurement results are given, including applications in nuclear structure physics and astrophysics, comparisons with
mass predictions, and the search for new isotopes and isomers. Further research potential will be available at next-generation
fragment-separator-storage-ring facilities such as the Super-FRS-CR-NESR complex at the future FAIR facility. 相似文献
994.
995.
Ulf-G Meißner 《The European Physical Journal A - Hadrons and Nuclei》2003,18(2-3):487-490
I present and discuss recent results on elastic pion-nucleon scattering and near-threshold neutral-pion electroproduction off deuterium obtained in the framework of chiral perturbation theory.Received: 30 September 2002, Published online: 22 October 2003PACS:
13.75.Gx Pion-baryon interactions - 25.30.Rw Electroproduction reactions - 12.39.Fe Chiral Lagrangians 相似文献
996.
Wojciech Połowczuk Piotr Więcek Tadeusz Radzik 《Mathematical Methods of Operations Research》2007,65(1):141-152
This paper gives wide characterization of n-person non-coalitional games with finite players’ strategy spaces and payoff functions having some concavity or convexity
properties. The characterization is done in terms of the existence of two-point-strategy Nash equilibria, that is equilibria
consisting only of mixed strategies with supports being one or two-point sets of players’ pure strategy spaces. The structure
of such simple equilibria is discussed in different cases. The results obtained in the paper can be seen as a discrete counterpart
of Glicksberg’s theorem and other known results about the existence of pure (or “almost pure”) Nash equilibria in continuous
concave (convex) games with compact convex spaces of players’ pure strategies. 相似文献
997.
M. Block D. Ackermann K. Blaum A. Chaudhuri Z. Di S. Eliseev R. Ferrer D. Habs F. Herfurth F. P. Heßberger S. Hofmann H.-J. Kluge G. Maero A. Martín G. Marx M. Mazzocco M. Mukherjee J. B. Neumayr W. R. Plaß W. Quint S. Rahaman C. Rauth D. Rodríguez C. Scheidenberger L. Schweikhard P. G. Thirolf G. Vorobjev C. Weber 《Hyperfine Interactions》2006,173(1-3):133-142
The Penning-trap mass spectrometer SHIPTRAP was designed for precision mass measurements of radionuclides produced in fusion–evaporation
reactions. The latest measurement campaign covered heavy nuclei (A>90) related to the astrophysical rapid proton capture process. The masses of 34 neutron-deficient radionuclides have been
measured since February 2006 with relative uncertainties between 5×10−8 and 1×10−7. Furthermore, the use of an octupolar RF excitation for the time-of-flight ion-cyclotron-resonance technique was investigated
and an increase of the resolving power by a factor of ten was observed in agreement with simulations. This will allow to resolve
isomeric states with excitation energies of a few 10 keV only.
相似文献
998.
999.
Georg Lieser Melanie Schroeder Holger Geßwein Volker Winkler Sven Glatthaar Murat Yavuz Joachim R. Binder 《Journal of Sol-Gel Science and Technology》2014,71(1):50-59
To find new cathode materials for future applications in lithium-ion batteries, lithium transition metal fluorides represent an interesting class of materials. In principle the Li intercalation voltage can be increased by replacing oxygen in the cathode host structure with the more electronegative fluorine. A facile pyrolytic sol–gel process with trifluoroacetic acid as fluorine source was established to synthesize monoclinic Li3FeF6 using nontoxic chemicals. The acicular Li3FeF6 powder was characterized with X-ray diffraction and a detailed structure model was calculated by Rietveld analysis. For the preparation of cathode films to cycle versus lithium monoclinic Li3FeF6 was ball milled with carbon and binder down to nanoscale. After 100 cycles galvanostatic cycling (C/20) 47 % fully reversible capacity of the initial capacity (129 mAh/g) could be retained. To the best of our knowledge the results presented in this work include the first rate performance test for monoclinic Li3FeF6 up to 1 C maintaining a capacity of 71 mAh/g. The redox reaction involving Fe3+/Fe2+ during Li insertion/extraction was confirmed by post-mortem XPS and cyclic voltammetry. 相似文献
1000.
Prof. René T. Boeré Janis Derendorf Prof. Carsten Jenne Dr. Sylwia Kacprzak Dr. Mathias Keßler Rainer Riebau Prof. Sebastian Riedel Dr. Tracey L. Roemmele Monika Rühle Dr. Harald Scherer Thomas Vent‐Schmidt Jonas Warneke Prof. Stefan Weber 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(15):4447-4459
The perhalogenated closo‐dodecaborate dianions [B12X12]2? (X=H, F, Cl, Br, I) are three‐dimensional counterparts to the two‐dimensional aromatics C6X6 (X=H, F, Cl, Br, I). Whereas oxidation of the parent compounds [B12H12]2? and benzene does not lead to isolable radicals, the perhalogenated analogues can be oxidized by chemical or electrochemical methods to give stable radicals. The chemical oxidation of the closo‐dodecaborate dianions [B12X12]2? with the strong oxidizer AsF5 in liquid sulfur dioxide (lSO2) yielded the corresponding radical anions [B12X12] ? ? (X=F, Cl, Br). The presence of radical ions was proven by EPR and UV/Vis spectroscopy and supported by quantum chemical calculations. Use of an excess amount of the oxidizing agent allowed the synthesis of the neutral perhalogenated hypercloso‐boranes B12X12 (X=Cl, Br). These compounds were characterized by single‐crystal X‐ray diffraction of dark blue B12Cl12 and [Na(SO2)6][B12Br12] ? B12Br12. Sublimation of the crude reaction products that contained B12X12 (X=Cl, Br) resulted in pure dark blue B12Cl12 or decomposition to red B9Br9, respectively. The energetics of the oxidation processes in the gas phase were calculated by DFT methods at the PBE0/def2‐TZVPP level of theory. They revealed the trend of increasing ionization potentials of the [B12X12]2? dianions by going from fluorine to bromine as halogen substituent. The oxidation of all [B12X12]2? dianions was also studied in the gas phase by mass spectrometry in an ion trap. The electrochemical oxidation of the closo‐dodecaborate dianions [B12X12]2? (X=F, Cl, Br, I) by cyclic and Osteryoung square‐wave voltammetry in liquid sulfur dioxide or acetonitrile showed very good agreement with quantum chemical calculations in the gas phase. For [B12X12]2? (X=F, Cl, Br) the first and second oxidation processes are detected. Whereas the first process is quasi‐reversible (with oxidation potentials in the range between +1.68 and +2.29 V (lSO2, versus ferrocene/ferrocenium (Fc0/+))), the second process is irreversible (with oxidation potentials ranging from +2.63 to +2.71 V (lSO2, versus Fc0/+)). [B12I12]2? showed a complex oxidation behavior in cyclic voltammetry experiments, presumably owing to decomposition of the cluster anion under release of iodide, which also explains the failure to isolate the respective radical by chemical oxidation. 相似文献