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71.
ONTHEBOUNDEDNESSANDTHESTABILITYRESULTSFORTHESOLUTIONOFCERTAINFOURTHORDERDIFFERENTIALEQUATIONSVIATHEINTRINSICMETHODCemilTUNC;A... 相似文献
72.
73.
Let (M,g) be an n-dimensional Riemannian manifold and T*M be its cotangent bundle equipped with the rescaled Sasaki type metric. In this paper, we firstly study the paraholomorphy property of the rescaled Sasaki type metric by using some compatible paracomplex structures on T*M. Second, we construct locally decomposable Golden Riemannian structures on T*M. Finally we investigate curvature properties of T*M. 相似文献
74.
We have measured electronic and Raman scattering spectra of 1,1',3,3'-tetraethyl-5,5',6,6'-tetrachloro-benzimidazolocarbocyanine iodide (TTBC) in various environments, and we have calculated the ground state geometric and spectroscopic properties of the TTBC cation in the gas and solution phases (e.g., bond distances, bond angles, charge distributions, and Raman vibrational frequencies) using density functional theory. Our structure calculations have shown that the ground state equilibrium structure of a cis-conformer lies ~200 cm(-1) above that of a trans-conformer and both conformers have C(2) symmetry. Calculated electronic transitions indicate that the difference between the first transitions of the two conformers is about 130 cm(-1). Raman spectral assignments of monomeric- and aggregated-TTBC cations have been aided by density functional calculations at the same level of the theory. Vibrational mode analyses of the calculated Raman spectra reveal that the observed Raman bands above 700 cm(-1) are mainly associated with the in-plane deformation of the benzimidazolo moieties, while bands below 700 cm(-1) are associated with out-of-plane deformations of the benzimidazolo moieties. We have also found that for the nonresonance excited experimental Raman spectrum of aggregated-TTBC cation, the Raman bands in the higher-frequency region are enhanced compared with those in the nonresonance spectrum of the monomeric cation. For the experimental Raman spectrum of the aggregate under resonance excitation, however, we find new Raman features below 600 cm(-1), in addition to a significantly enhanced Raman peak at 671 cm(-1) that are associated with out-of-plane distortions. Also, time-dependent density functional theory calculations suggest that the experimentally observed electronic transition at ~515 nm (i.e., 2.41 eV) in the absorption spectrum of the monomeric-TTBC cation predominantly results from the π → π? transition. Calculations are further interpreted as indicating that the observed shoulder in the absorption spectrum of TTBC in methanol at 494 nm (i.e., 2.51 eV) likely results from the ν(") = 0 → ν' = 1 transition and is not due to another electronic transition of the trans-conformer-despite the fact that measured and calculated NMR results (not provided here) support the prospect that the shoulder might be attributable to the 0-0 band of the cis-conformer. 相似文献
75.
In this note, we reply to the comments by Rees and Magyari (2007) on our article (Aydin and Kaya 2007). They mainly stated
that the thermal boundary conditions we defined at the edge of the boundary layer were incompatible with the energy equation.
This is questionable and therefore we will discuss it below. They disclosed that our results were in error. However, this
is quite misleading. Scientifically, they cannot reach such a conclusion without comparing our results with what they thought
to be correct. In fact, this misleading and unproven statement will be shown not to be correct in the following. 相似文献
76.
Aydin Tavman Naz M. Agh-Atabay Abdollah Neshat Fahrettin Gucin Basaran Dulger Durata Haciu 《Transition Metal Chemistry》2006,31(2):194-200
2-(5-H/methyl-1H-benzimidazol-2-yl)-4-bromo/nitro-phenol (HLx:X=1–4) ligands and their iron(III) nitrate complexes have been synthesized and characterized. In all of the complexes, the
ligands are bidentate, via one imine nitrogen atom and a phenolate oxygen atom. The coordination is completed with a bidentate nitrate anion, and a
water molecule. Elemental analysis, molar conductivity, magnetic susceptibility, FT-Raman, FT-IR (mid i.r., far i.r.), UV–visible
and as well as quantum chemical calculations performed with CACHE are in agreement with a 1:1 electrolyte structures that
are mononuclear, and distorted 5-coordinate square pyramidal. The antimicrobial activities of free ligands, their hydrochloride
salts and the complexes were evaluated using the disk diffusion method in dimethyl sulfoxide (DMSO) toward nine bacteria,
each with multiple, fresh clinical isolates, and the results are compared with those for penicillin-g, ampicillin, cefotaxime,
vancomycine, oflaxacin and tetracycline. Antifungal activities were reported for Kluyveromyces fragilis, Rhodotorula rubra, Candida albicans, Hanseniaspora Guilliermondii and Debaryomyces hansenii yeasts, each with multiple isolates, and the results were referenced against nystatin, ketaconazole and clotrimazole antifungal
agents. In most cases, the compounds tested showed broad-spectrum (Gram+ and Gram−) activities that were either more active or as potent as the references particularly as antifungal agents. 相似文献
77.
D. Knittel P. Valenta M. Aydin W. A. König 《Fresenius' Journal of Analytical Chemistry》1985,322(6):581-582
Summary Thiosulfate, a potential substrate for sulfuric acid forming thiobacilli, could be detected and quantitatively determined in corroded concrete sewer systems by differential pulse anodic-stripping voltammetry. The method proved to be specific and gave reproducible results for concentrations from 5 ppb to 3 ppm of thiosulfate in aqueous media.
Spurenanalyse von Thiosulfat in korrodierten Beton-Abwasserkanälen durch differentielle Puls-Anodic-Stripping-Voltammetrie (DPASV)
Zusammenfassung Thiosulfat, ein potentielles Substrat für Schwefelsäure bildende Thiobazillen, konnte in korrodierten Abwasserkanälen aus Beton mittles der differentiellen Puls-Anodic-Stripping-Voltammetrie (DPASV) nachgewiesen und quantifiziert werden. Die Methode erwies sich als spezifisch und ergab reproduzierbare Ergebnisse für Thiosulfatkonzentrationen zwischen 5 ppb und 3 ppm in wäßrigen Medien.相似文献
78.
R. Aydin R. Aldenhoven L. Degener H. Gebauer G. Meisel 《Zeitschrift für Physik A Hadrons and Nuclei》1975,273(3):233-238
Theg J factors of the metastable states3 P 2 of88Sr and3 D 1,3 D 2,3 D 3, and1 D 2 of138Ba have been measured using the atomic-beam magnetic resonance method. The metastable states were populated by an electric discharge within the atomic-beam source. From the measurements of rf transitions between the Zeeman levels (m J =+1)?(m J =?1) we obtained:88Sr:g J (3 P 2) =1.501124(10)138Ba:g J (3 D 3)=1.3340823 (10)g J (3 D′2)=1.1637406(11)g J (3 D 1)=0.4985751(13)g J (1 D′2)=1.003 1449(10). The relativistic and diamagnetic corrections for theg J factor of the3 P 2 state of Sr have been calculated. With these and the Schwinger correction included we getg J (3 P 2)=1.501119(12). 相似文献
79.
Rafet Aydin Harald Günther Jan Runsink Hans Schmickler Horst Seel 《Magnetic resonance in chemistry : MRC》1980,13(3):210-215
The 13C, 1H spin-spin coupling constants have been determined for π-benzenechromium tricarbonyl (3) and the π-tropyliumchromium tricarbonyl cation using the 13C{2H}double resonance technique described in a previous paper. In addition, conventional analysis of the 1H-coupled 13C NMR spectrum of 3 was carried out and the 1H NMR spectrum of 3 partially oriented in the nematic phase was analysed. Both treatments also allowed the determination of the 1H, 1H coupling constants for this compound. The nJ(CH) results are discussed on the basis of structural data and the theoretical results available. The complexation effects for 1J(CH) are found to correlate with the C? H overlap population and hybridization changes, and those for 3J(CH) with the CC bond lengths and π-bond orders. The dependence of 2J(CH) on CC bond length as well as on the CCH bond angle is indicated. The liquid crystal results are compared with those of related studies. 相似文献
80.
Mössbauer and X-ray spectra for taenite lamellae from the iron meteorite Cape York show that the lamellae contain an ordered phase with the composition FeNi, and with the structure L10. This phase has not previously been detected in meteorites. 相似文献