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41.
Technical Physics - The structural state in the zones of indentation and scratch testing of Ti–Al–Si–Cu–N gradient coatings has been studied using dark-field electron... 相似文献
42.
Optics and Spectroscopy - The luminescence properties of colloidal Ag2S quantum dots (QDs) with ZnS or SiO2 shells coated with thioglycolic or 2-mercaptopropionic acids are comparatively analyzed.... 相似文献
43.
Calculations of the C3H6 · LiH, C4H8 · M+, and C4H8 · MH systems and of C2H2 · MH complexes (M = Li or Na) were carried out by the unrestricted Hartree-Fock-Roothaan (UHF) method with partial optimization of the geometry using fixed geometric parameters of the C3H6 and C4H8 molecules. The standard 3-21G and 6-31G* basis sets were used. Unlike the C3H6 · LiH structure, the C4H8 · M+ and C4H8 · MH systems are typical complexes. It was found that the C4H8 · M+, C4H8 · MH, and C2H2 · MH complexes are similar in coordination of M+ ions and MH molecules by carbon atoms in spite of considerable differences in the interatomic distances (–1 A) between these atoms in the C4H8 and C2H2 molecules. The heats of formation (Q), which were calculated in the UHF/6-31G* approximation and using second- and fourth-order Möller-Plesset perturbation theory taking into account the electron correlation energy in the MP2/6-31G*. MP4(SDQ)/6-31G*, and MP4(SDTQ)/6-31G* approximations, satisfy the following relationships: Q(C2H3 · MH) < Q(C4H8 · MH) < Q(C4H8 · M+). It was observed that in going from Li to Na the corresponding values of Q tend to decrease.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya. No. 7, pp. 1636–1640, July, 1996. 相似文献
44.
Reflection and absorption of a linearly polarized wave by a plasma with developed ion-acoustic turbulence is studied. The
dependences of the absorption coefficient and Stokes parameters of the reflected elliptically polarized wave on the anisotropic
effective frequency of electron collisions are established. 相似文献
45.
D. V. Ovchinnikov E. N. Glibin A. V. Garabadzhiu N. G. Plekhanova 《Russian Journal of General Chemistry》2010,80(4):809-813
A number of actinocin amides containing residues of aza-15-crown-5 and aza-18-crown-6 where crown fragments were separated
from the heterocyclic chromophore by the residues of ω-amino acids were obtained as actinomycin D models. 相似文献
46.
A.A. Ovchinnikov 《Physics letters. A》2009,373(3):305-307
We apply the theorems from the theory of Toeplitz determinants to calculate the asymptotics of various correlators including the exponential ones in the inpenetrable one-dimensional Bose gas system. The known correlators in the free-fermion system are also used to test the generalized Fisher-Hartwig conjecture. 相似文献
47.
M. A. Ershov E. V. Grigor’eva A. I. Guseva N. Ya. Vinogradova D. A. Potanin V. S. Dorokhov P. A. Nikul’shin K. A. Ovchinnikov 《Russian Journal of Applied Chemistry》2017,90(9):1402-1411
Prospects for using furfural derivatives as octane boosters for gasoline are discussed on the basis of analysis of their physicochemical and operation properties. Knock resistance data, toxicity parameters, and results of motor bench tests are considered for furan compounds, furfural ethers, furfurylamine, and other furfural derivatives. 相似文献
48.
S. G. Ovchinnikov 《JETP Letters》1996,64(1):25-31
The Fermi and Bose quasiparticle spectrum in copper oxides is studied in a many-band p-d model taking account of the strong electronic correlations. It is shown that hole-doped systems possess a Bose mode — a spin
exciton — which is associated with the singlet-triplet excitation of the two-hole ground-state term of CuO4 clusters. Intercluster hopping leads to fermion-boson interaction with a spin exciton as the intermediate boson. Such a mechanism
does not exist for n-type systems.
Pis'ma Zh. éksp. Teor. Fiz. 64, No. 1, 23–28 (10 July 1996) 相似文献
49.
The electronic structure of graphite, polyacene and cumulene are calculated by a generalised Hartree-Fock method, where electrons with different spins occupy different molecular Orbitals.
Zusammenfassung Die Elektronenstruktur von Graphit, Polyacen und Cumulen wurden mittels einer verallgemeinerten Hartree-Fock-Methode berechnet, wobei Elektronen mit verschiedenem Spin verschiedene Orbitale besetzen können.
Résumé Les structures électroniques du graphite, du polyacène et du cumulène sont calculées par la méthode de Hartree-Fock généralisée, ou des électrons de spin différent occupent des orbitales moléculaires différentes.相似文献
50.