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排序方式: 共有253条查询结果,搜索用时 375 毫秒
121.
122.
A series of new oxygen-, nitrogen- and sulfur- containing spiro heterocycles was synthesized by reactions of 2-(3-hydroxy-5,5-dimethylcyclohex-2-enylidene)malononitrile with some active methylene and bidentate compounds. 相似文献
123.
Singh Shashank Oswal Mumtaz Behera B. R. Kumar Ashok Santra S. Acharya R. Singh K. P. 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(3):1443-1449
Journal of Radioanalytical and Nuclear Chemistry - Elemental concentrations namely P, S, Cl, K, Ca, Sc, Ti, Mn, Fe, Cu, Zn, Rb, Br and Sr were determined using Particle Induced X-ray Emission... 相似文献
124.
125.
M. Mitra H. Ghosh S.N. Behera 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,2(3):371-380
The role of electron correlation on different pairing symmetries are discussed in details where the electron correlation has
been treated within the slave boson formalism. It is shown that for a pure s or pure d wave pairing symmetry, the electronic
correlation suppresses the s wave gap magnitude (as well as the ) at a faster rate than that for the d wave gap. On the other hand, a complex order parameter of the form () shows anomalous temperature dependence. For example, if the temperature () at which the d wave component of the complex order parameter vanishes happens to be larger than that for the s wave component
(), then the growth of the d wave component is arrested with the onset of the s wave component of the order parameter. In this
mixed phase however, we find that the suppression in different components of the gap as well as the corresponding due to coulomb correlation are very sensitive to the relative pairing strengths of s and d channels as well as the underlying
lattice. Interestingly enough, in such a scenario (for a case of )the gap magnitude of the d wave component increases with electron correlation but not for certain values of electron correlation. However, this never happens in case of the s wave component. We also calculate
the temperature dependence of the superconducting gap along both the high symmetry directions ( and ) in a mixed symmetry pairing state and the thermal variation of the gap anisotropy [0pt][0pt] with electron correlation. The results
are discussed with reference to experimental observations.
Received: 26 August 1997 / Revised: 31 December 1997 /
Accepted: 28 January 1998 相似文献
126.
Behera SK 《Chemical communications (Cambridge, England)》2011,47(37):10371-10373
Monodispersed Fe(3)O(4) nanoparticles of size ~10 nm were processed by a simple ultrasonic assisted co-precipitation method, mechanically mixed with graphene oxide, and thermally reduced to form a magnetite-graphene composite. Electrochemical characterization of the Fe(3)O(4)-graphene nanocomposites showed excellent capacity in excess of 1200 mA h g(-1), and exceptional stability during high current cycling for at least 1000 cycles. 相似文献
127.
Abramowski A Acero F Aharonian F Akhperjanian AG Anton G Barnacka A de Almeida UB Bazer-Bachi AR Becherini Y Becker J Behera B Bernlöhr K Bochow A Boisson C Bolmont J Bordas P Borrel V Brucker J Brun F Brun P Bulik T Büsching I Carrigan S Casanova S Cerruti M Chadwick PM Charbonnier A Chaves RC Cheesebrough A Chounet LM Clapson AC Coignet G Conrad J Dalton M Daniel MK Davids ID Degrange B Deil C Dickinson HJ Djannati-Ataï A Domainko W Drury LO Dubois F Dubus G Dyks J Dyrda M Egberts K Eger P 《Physical review letters》2011,106(16):161301
A search for a very-high-energy (VHE; ≥100 GeV) γ-ray signal from self-annihilating particle dark matter (DM) is performed towards a region of projected distance r~45-150 pc from the Galactic center. The background-subtracted γ-ray spectrum measured with the High Energy Stereoscopic System (H.E.S.S.) γ-ray instrument in the energy range between 300 GeV and 30 TeV shows no hint of a residual γ-ray flux. Assuming conventional Navarro-Frenk-White and Einasto density profiles, limits are derived on the velocity-weighted annihilation cross section (σv) as a function of the DM particle mass. These are among the best reported so far for this energy range and in particular differ only little between the chosen density profile parametrizations. In particular, for the DM particle mass of ~1 TeV, values for (σv) above 3×10(-25) cm(3)?s(-1) are excluded for the Einasto density profile. 相似文献
128.
We present a model study of magnetoresistance through the interplay of magnetisation, structural distortion and external magnetic field for the manganite systems. The manganite system is described by the Hamiltonian which consists of the s-d type double exchange interaction, Heisenberg spin-spin interaction among the core electrons, and the static and dynamic band Jahn-Teller (JT) interaction in the e(g) band. The relaxation time of the e(g) electron is found from the imaginary part of the Green's function using the total Hamiltonian consisting of the interactions due to the electron and phonon. The calculated resistivity exhibits a peak in the pure JT distorted insulating phase separating the low temperature metallic ferromagnetic phase and the high temperature paramagnetic phase. The resistivity is suppressed with the increase of the external magnetic field. The e(g) electron band splitting and its effect on magnetoresistivity is reported here. 相似文献
129.
This paper investigates the numerical solution of a viscoelastic continuous beam whose damping behaviours are defined in term of fractional derivatives of arbitrary order. The Homotopy Perturbation Method (HPM) is used to obtain the dynamic response. Unit step function response is considered for the analysis. The obtained results are depicted in various plots. From the results obtained it is interesting to note that by increasing the order of the fractional derivative the beam suffers less oscillation. Similar observations have also been made by keeping the order of the fractional derivative constant and varying the damping ratios. Comparisons are made with the analytic solutions obtained by Zu-feng and Xiao-yan [Appl. Math. Mech. 28, 219 (2007)] to show the effectiveness and validation of this method. 相似文献
130.
Debidatta Behera M. Boudjelal M. Batouche T. Seddik Dj. Hemidi Sanat Kumar Mukherjee 《International journal of quantum chemistry》2024,124(1):e27342
This study employed density functional theory (DFT) embedded in Wien2K code to evaluate the physical features of the XGeCl3 (X = Rb/Cs) cubic halide perovskites. The structural optimization has been performed considering generalized gradient approximation (GGA) and electronic properties have been computed considering modified Becke-Johnson potential (mBJ). The formation energy and phonon dispersion analysis establish the stability of the investigated compounds. Mechanical stability is further confirmed by the computed diverse elastic coefficients. It has been discovered that the examined substances are naturally ductile. The refractive index, reflectivity, and absorption coefficient, are among the optical parameters that have been estimated and analyzed. Interesting results have been obtained for the transport properties of XGeCl3 (X = Rb/Cs). The XGeCl3 (X = Rb/Cs) exhibits a high Seebeck coefficient (X = Rb/Cs) and the largest figure of merit (about 0.99), indicating significant potential for thermoelectric applications. 相似文献