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91.
Mathematical modeling of localized melting around graphite nodules during laser surface hardening of austempered ductile iron 总被引:1,自引:0,他引:1
An attempt has been made to mathematically predict the optimum conditions of laser surface hardening (LSH) of austempered ductile iron (ADI) that can ensure a predominantly martensitic microstructure and preclude partial/complete dissolution of graphite nodules in the laser hardened zone during laser irradiation. The exercise involves prediction of the thermal profile (using the Ashby and Easterling model), and consequently, the carbon diffusion profile around the graphite nodules at different depths from the surface for the given conditions of LSH. Microstructural investigations have been carried out by optical and scanning electron microscopy to study the morphology, shape and width of the partially/completely melted graphite nodules as a function of the LSH parameters. Finally, the predicted maximum width of the melted zone around the graphite nodules is compared with the relevant experimental data to validate the proposed model. 相似文献
92.
Kyosuke Morimoto Thien Phuc Le Sudipta Kumar Manna I. N. Chaithanya Kiran Shinji Tanaka Masato Kitamura 《化学:亚洲杂志》2019,14(19):3221-3221
93.
Aliakbar Dehno Khalaji Sepideh Maghsodlou Rad Gholamhossein Grivani Karla Fejfarova Michal Dusek Debasis Das 《Journal of chemical crystallography》2011,41(8):1145-1149
Abstract
Schiff-base compound (E)-4-dimethamino[(1-phenylethyl)iminomethyl]benzyne was synthesized and characterized by elemental analyses (CHN), FT-IR and 1H-NMR spectroscopic techniques and thermogravimetric analyses (TG). Crystal structure of the title compound was obtained by single crystal X-ray diffraction. The title compound crystallizes in the monoclinic space group P21 with unit cell parameters: a = 8.5283(2), b = 6.0699(2), c = 13.6997(4) Ǻ, β = 91.471(2)°, V = 708.94(4) Ǻ3 and Z = 2. 相似文献94.
This paper analyzes a delay logistic equation which models a feedback control problem. Interval map associated to the system is derived. By calculating Lyapunov exponent, we indicate stable orbit and chaotic phenomenon respectively. The results are verified through computer simulation. We identify the parameter which controls the dynamics. 相似文献
95.
George G. Roussas Debasis Bhattacharya 《Statistical Inference for Stochastic Processes》2009,12(2):185-201
Under suitable regularity conditions imposed on a general discrete time-parameter stochastic process, the Hájek-Inagaki convolution
representation theorem is established for randomly stopped locally asymptotically mixed normal experiments.
D. Bhattacharya: On leave from Visva-Bharati University, Santiniketan, India. 相似文献
96.
Pellegrino T Fiore A Carlino E Giannini C Cozzoli PD Ciccarella G Respaud M Palmirotta L Cingolani R Manna L 《Journal of the American Chemical Society》2006,128(20):6690-6698
We describe an approach to synthesize colloidal nanocrystal heterodimers composed of CoPt(3) and Au. The growth is based on the nucleation of gold domains on preformed CoPt(3) nanocrystals. It is a highly versatile methodology which allows us to tune independently the size of the two domains in each dimer by varying several reaction parameters. The statistical analysis of the distribution of the domain sizes in the dimers and the compositional mapping achieved by dark field imaging and energy dispersive spectroscopy confirm that the two domains in each dimer are indeed made of CoPt(3) and Au, respectively. Structural characterization by high-resolution transmission electron microscopy shows that the two domains, both having cubic fcc Bravais lattice, can share a common {111}, {100}, or {110} facet, depending on the size of the initial CoPt(3) seeds. The magnetization measurements evidence a ferromagnetic CoPt(3) phase with a relatively low anisotropy as a consequence of their disordered crystalline structure, regardless of the presence of a Au tip. We believe that this prototype of nanocrystal dimer, which can be manipulated under air, can find several applications in nanoscience, as the Au section can be exploited as the preferential anchor point for various molecules, while the CoPt(3) domain can be used for magnetic detection. 相似文献
97.
Tuhina Manna Farook Rahaman Sabiruddin Molla Jhumpa Bhadra Hasrat Hussain Shah 《General Relativity and Gravitation》2018,50(5):54
In this paper we have investigated the gravitational lensing phenomenon in the strong field regime for a regular, charged, static black holes with non-linear electrodynamics source. We have obtained the angle of deflection and compared it to a Schwarzschild black hole and Reissner Nordström black hole with similar properties. We have also done a graphical study of the relativistic image positions and magnifications. We hope that this method may be useful in the detection of non-luminous bodies like this current black hole. 相似文献
98.
Nirmalendu Biswas Prokash C. Roy Nirmal K. Manna Achintya Mukhopadhyay Swarnendu Sen 《显形杂志》2014,17(3):221-233
99.
Y. Chushkin F. Zontone E. Lima L. De Caro P. Guardia L. Manna C. Giannini 《Journal of synchrotron radiation》2014,21(3):594-599
The progress of tomographic coherent diffractive imaging with hard X‐rays at the ID10 beamline of the European Synchrotron Radiation Facility is presented. The performance of the instrument is demonstrated by imaging a cluster of Fe2P magnetic nanorods at 59 nm 3D resolution by phasing a diffraction volume measured at 8 keV photon energy. The result obtained shows progress in three‐dimensional imaging of non‐crystalline samples in air with hard X‐rays. 相似文献
100.
A Das MR Molla B Maity D Koley S Ghosh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(32):9849-9859
This paper reports comprehensive studies on the mixed assembly of bis-(trialkoxybenzamide)-functionalized dialkoxynaphthalene (DAN) donors and naphthalene-diimide (NDI) acceptors due the cooperative effects of hydrogen bonding, charge-transfer (CT) interactions, and solvophobic effects. A series of DAN as well as NDI building blocks have been examined (wherein the relative distance between the two amide groups in a particular chromophore is the variable structural parameter) to understand the structure-dependent variation in mode of supramolecular assembly and morphology (organogel, reverse vesicle, etc.) of the self-assembled material. Interestingly, it was observed that when the amide functionalities are introduced to enhance the self-assembly propensity, the mode of co-assembly among the DAN and NDI chromophores no longer remained trivial and was dictated by a relatively stronger hydrogen-bonding interaction instead of a weak CT interaction. Consequently, in a highly non-polar solvent like methylcyclohexane (MCH), although kinetically controlled CT-gelation was initially noticed, within a few hours the system sacrificed the CT-interaction and switched over to the more stable self-sorted gel to maximize the gain in enthalpy from the hydrogen-bonding interaction. In contrast, in a relatively less non-polar solvent such as tetrachloroethylene (TCE), in which the strength of hydrogen bonding is inherently weak, the contribution of the CT interaction also had to be accounted for along with hydrogen bonding leading to a stable CT-state in the gel or solution phase. The stability and morphology of the CT complex and rate of supramolecular switching (from CT to segregated state) were found to be greatly influenced by subtle structural variation of the building blocks, solvent polarity, and the DAN/NDI ratio. For example, in a given D-A pair, by introducing just one methylene unit in the spacer segment of either of the building blocks a complete change in the mode of co-assembly (CT state or segregated state) and the morphology (1D fiber to 2D reverse vesicle) was observed. The role of solvent polarity, structural variation, and D/A ratio on the nature of co-assembly, morphology, and the unprecedented supramolecular-switching phenomenon have been studied by detail spectroscopic and microscopic experiments in a gel as well as in the solution state and are well supported by DFT calculations. 相似文献