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251.
Priyank Kumar Nisarg K. Bhatt Pulastya R. Vyas Vinod B. Gohel 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(10):219
The thermophysical properties of rhodium are studied up to melting temperature by incorporating anharmonic effects due to lattice ions and thermally excited electrons. In order to account anharmonic effects due to lattice vibrations, we have employed mean field potential (MFP) approach and for thermally excited electrons Mermin functional. The local form of the pseudopotential with only one effective adjustable parameter rc is used to construct MFP and hence vibrational free energy due to ions – Fion. We have studied equation of state at 300 K and further, to access the applicability of present conjunction scheme, we have also estimated shock-Hugoniot and temperature along principle Hugoniot. We have carried out the study of temperature variation of several thermophysical properties like thermal expansion (βP), enthalpy (EH), specific heats at constant pressure and volume (CP and CV), specific heats due to lattice ions and thermally excited electrons (CVion and CVel, isothermal and adiabatic bulk moduli (BT and Bs) and thermodynamic Gruneisen parameter (γth) in order to examine the inclusion of anharmonic effects in the present study. The computed results are compared with available experimental results measured by using different methods and previously obtained theoretical results using different theoretical philosophy. Our computed results are in good agreement with experimental findings and for some physical quantities better or comparable with other theoretical results. We conclude that local form of the pseudopotential used accounts s-p-d hybridization properly and found to be transferable at extreme environment without changing the values of the parameter. Thus, even the behavior of transition metals having complexity in electronic structure can be well understood with local pseudopotential without any modification in the potential at extreme environment. Looking to the success of present scheme (MFP + pseudopotential) we would like to extend it further for the study of liquid state properties as well as thermophysical properties of d and f block metals. 相似文献
252.
253.
B. C. Joshi Bhawna Khulbey Deepak Upreti Charu Chandra Dhaundiyal 《Indian Journal of Physics》2010,84(4):405-412
A study of energy transfer from samarium to erbium ions in zinc phosphate glass has been performed for a range of donor (1.0
wt% fixed) and acceptor concentrations ranging from 0.2 wt% to 1.2 wt%. The intensity of emission spectra of Sm3+ ions in the presence of Er3+ ions shows an overall decrease, thereby suggesting a non radiative energy transfer from Sm3+ ions to Er3+ ions. The interaction mechanism between the donor and acceptor ions is found to be mainly electric dipole-dipole in nature.
The parameters required for the quantitative study of energy transfer e.g. energy transfer efficiencies, transfer probabilities,
critical transfer distances have been computed. 相似文献
254.
The CIDNP behaviour in the photochemical reduction of a series of 1,4-benzoquinones in 2-propanol was studied systematically in detail at low fields. The radical pair model formulated by Lawler and co-workers was extended to interpret the present results. It is of interest to note that the polarization crossover occurs at relatively high fields compared to other known systems and it is insensitive to the number of protons in the various quinones. 相似文献
255.
Diglycine sulfate single crystals are grown from aqueous solution by evaporation method. The effect of growth conditions are studied with respect to the perfection and morphology of the crystals. The seed history, growth temperature and pH of the solution are found to bear pronounced effects. The results are reported in the present paper. 相似文献
256.
Single crystals of anhydrous diglycine sulfate are grown at constant temperature by evaporation method. The crystals are grown at various temperatures and their growth rate is determined. A chemical etchant for dislocation studies is reported. The perfection of the crystals grown at various temperatures has been studied using etching technique. It is found that the crystals contained inclusions of the mother liquid. The crystals grown below 28° are almost free of inclusions and the dislocation density is also low. 相似文献
257.
Along with certain properties of a chional isomorphism, it is proved that to convert a chronal isomorphism into a causal isometry, we need only the distinguishingness of one of the space-times. 相似文献
258.
Plane-wave density functional theory calculations were performed to investigate the binding and diffusion of hydrogen on three flat Ni surfaces, Ni(100), Ni(110), and Ni(111), and two stepped Ni surfaces, Ni(210) and Ni(531). On each surface, the favored adsorption sites were identified by considering the energy and stability of various binding sites and zero-point energy corrections were computed. Binding energies are compared with experimental and theoretical results from the literature. Good agreement with experimental and previous theoretical data is found. At surface coverages where adsorbate-adsorbate interactions are relatively weak, the binding energy of H is similar on the five Ni surfaces studied. Favorable binding energies are observed for stable surface sites, while subsurface sites have unfavorable values relative to the gas phase molecular hydrogen. Minimum energy paths for hydrogen diffusion on Ni surfaces and into subsurface sites were constructed. 相似文献
259.
[reaction: see text] Iron(III) porphyrin complexes Fe(Por)Cl are effective catalysts for aziridination of alkenes using bromamine-T as the nitrene source. The catalytic system can operate under mild conditions with alkenes as limiting reagents. The aziridination reaction is general and suitable for a wide variety of alkenes, including aromatic, aliphatic, cyclic, and acyclic olefins, as well as alpha,beta-unsaturated esters. For 1,2-disubstituted olefins, the reactions proceeded with moderate to low stereospecificity. 相似文献
260.