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111.
112.
113.
LetE be a complex Banach space with open unit ballB
e. The structure of the space of composition operators on the Banach algebra H∞, of bounded analytic functions onB
e with the uniform topology, is studied. We prove that the composition operators arising from mappings whose range lies strictly
insideB
e form a path connected component. WhenE is a Hilbert space or aC
o(X)- space, the path connected components are shown to be the open balls of radius 2.
The research of this author was supported by grant number SAB1999-0214 from the Ministerio de Educación, Cultura y Deporte
during his stay at the Universidad de Valencia.
The research of this author was partially supported DGES(Spain) pr. 96-0758.
The research of this author was partially supported by Magnus Ehrnrooths stiftelse. 相似文献
114.
Phage-displayed alanine shotgun scanning was used to dissect contributions by engrailed homedomain (En-HD) residues 17 through 46, which indirectly influence recognition of DNA. The relative contributions of such indirect contacts, quantified by shotgun scanning, highlight previously unexplored En-HD residues. Two motifs dominate En-HD function in this region. First, two surface-exposed aromatic residues (F20 and Y25) bracket the hydrophobic core. Second, two sets of turn-forming residues are highlighted, including carboxamide-requiring residues E22/N23 and a leucine/isoleucine splint. The En-HD hydrophobic core exhibits a surprising degree of malleability, as demonstrated by homolog shotgun scanning. Most selectants from in vitro shotgun scanning mirror the consensus human homeodomain sequence. Thus, natural evolution and in vitro selection use similar selection criteria: affinity, specificity, and stability. However, homolog shotgun scanning identified mutations capable of improving the affinity and specificity of En-HD. 相似文献
115.
Aron Kuppermann 《Chemical physics letters》1975,32(2):374-375
We present in this paper a mapping of triatomic three-dimensional Born-Oppenheimer potential energy surfaces V for which all arrangement channels are represented evenhandedly. This representation is very useful for visualizing the geometrical and dynamical properties of such surfaces. 相似文献
116.
The electron impact excitation spectrum 0f 1,3-butadiene has been studied at 20, 35 and 55 eV impact energies and scattering angles of 10° to 80°. Two low lying states are observed with maxima at 3.2 and 4.9 eV, and are identified as the 3Bu state and 3Ag state respectively 相似文献
117.
Chang-Hoon Kim Zentaro Akase Lichun Zhang Arthur H. Heuer Aron E. Newman 《Journal of solid state chemistry》2006,179(3):753-774
The presence of ε-MnO2 as a major component of electrolytic manganese dioxide (EMD) has been demonstrated by a combined X-ray diffraction/transmission electron microscopy (TEM) study. ε-MnO2 usually has a partially ordered defect NiAs structure containing 50% cation vacancies; these vacancies can be fully ordered by a low temperature (200 °C) heat treatment to form a pseudohexagonal but monoclinic superlattice.Numerous fine-scale anti-phase domain boundaries are present in ordered ε-MnO2 and cause extensive peak broadening and a massive shift of a very intense, 0.37 nm superlattice peak. This suggests a radically different explanation of the ubiquitous, very broad ∼0.42 nm peak (∼21-22° 2θ, CuKα radiation) in EMDs, which heretofore has been attributed to Ramsdellite containing numerous planar defects. This work confirms the multi-phase model of equiaxed EMDs proposed by Heuer et al. [ITE Lett. 1(6) (2000) B50; Proc. Seventh Int. Symp. Adv. Phys. Fields 92 (2001)], rather than the defective single-phase model of Chabre and Pannetier [Prog. Solid State Chem. 23 (1995) 1] and Bowden et al. [ITE Lett. 4(1) (2003) B1]. 相似文献
118.
In order to calculate the transition probabilities (or cross sections) for reactive collisions, such as A + BC(ν, j)→ AB(ν′, j) + C, using the quasi-classical trajectory method, one quantizes the internal energy of the reagents and in addition adopts some algorithm for calculating the internal quantum numbers of the products. A serious consequence of this procedure is that the quasi-classical results do not obey microscopic reversibility. It is shown that for the collinear F + H2(ν = 0) → FH(ν = 2, 3)+ H reaction (and its D2 counterpart), the quasi-classical trajectory probabilities for the reverse reaction not only differ substantially from the forward ones but in general are in much better agreement with accurate quantum calculations. A similar situation was found for the collinear H + H2(0) → H2(1) + H reaction. We suggest that in doing quasi-classical calculations, the reverse of the process of interest should also be considered. Comparison of forward and reverse quasi-classical collinear calculations with accurate collinear quantum results could give an indication of whether forward or reverse calculations should be used for the three-dimensional case. 相似文献
119.
Thomas Aussieker Hans‐Lothar Keller Thorsten Oldag Yurii Prots Michael Ruck Prof. Dr. Aron Wosylus 《无机化学与普通化学杂志》2007,633(4):603-609
Dark grey (dark red with transmitting light) crystals of heptathallium(I) hexadecaiodo‐tribismuthate(III), Tl7Bi3I16, were obtained by slow cooling of a melt from 800 K to ambient temperature and, with higher crystal quality via solvothermal synthesis in aqueous HI by slowly cooling from 428 to 363 K. The compound is diamagnetic and melts congruently at 630(5) K. X‐ray diffraction on single‐crystals revealed that Tl7Bi3I16 crystallizes in the orthorhombic space group Cmcm with lattice parameters a = 2473.4(5), b = 1441.9(2), c = 3616.9(7) pm. The crystal structure can be interpreted as a layered intergrowth of fragments from the CsNiCl3 and K5Dy3I12 structure types with isolated [BiI6]3? octahedra and [Bi2I10]4? double octahedra. Rotation and distortion of the complex anions establish coordination numbers (c.n.) between 7 and 9 for the Tl+ cations. Dark red crystals of trithallium(I) hexaiodo‐bismuthate(III), Tl3BiI6, are only accessible via hydrothermal synthesis in aqueous HI and slowly cooling from 428 to 363 K. Thermal analysis reveals a peritectoid decomposition at 540(5) K into the neighboring phases Tl7Bi3I16 and TlI. Tl3BiI6 crystallizes in the monoclinic space group P21/c with lattice parameters a = 1352.6(3), b = 899.6(2), c = 1353.8(3) pm, and β = 104.18(3)°. In the crystal structure isolated [BiI6]3? octahedra are arranged according to the motif of a face‐centered pseudo‐cubic packing. Due to the tilted orientation of the [BiI6]3? groups the Tl+ cations have c.n. of 8 and 9. Although the crystal structure of Tl3BiI6 looks like a distorted variant of the elpasolith type, there is no symmetry relation according to a group subgroup formalism. 相似文献
120.