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141.
M. Blennow T. Ohlsson W. Winter 《The European Physical Journal C - Particles and Fields》2007,49(4):1023-1039
We investigate non-standard Hamiltonian effects on neutrino oscillations, which are effective additional contributions to
the vacuum or matter Hamiltonian. Since these effects can enter in either the flavor or mass basis, we develop an understanding
of the difference between these bases representing the underlying theoretical model. In particular, the simplest of these
effects are classified as “pure” flavor or mass effects, where the appearance of such a “pure” effect can be quite plausible
as a leading non-standard contribution from theoretical models. Compared to earlier studies investigating particular effects,
we aim for a top–down classification of a possible “new physics” signature at future long-baseline neutrino oscillation precision
experiments. We develop a general framework for such effects with two neutrino flavors and discuss the extension to three
neutrino flavors, and we demonstrate the challenges for a neutrino factory to distinguish the theoretical origin of these
effects with a numerical example as well. We find how the precision measurements of neutrino oscillation parameters can be
altered by non-standard effects alone (not including non-standard interactions in the creation and detection processes) and
that the non-standard effects on Hamiltonian level can be distinguished from other non-standard effects (such as neutrino
decoherence and decay) if we consider the specific imprint of the effects on the energy spectra of several different oscillation
channels at a neutrino factory. 相似文献
142.
The phase transition during chemical lithium insertion into α-MoO3 was investigated by chemical analysis, X-ray diffraction (XRD) and electrochemical characterisation. The samples have been
prepared by reaction of various amounts of water-free lithium iodide with fine-particulate orthorhombic molybdenum trioxide
in n-hexane (non-aqueous media), which yielded materials with different Li/Mo ratio. XRD investigations of these materials proved
that the crystal structure of the layered α-MoO3 has been changed after the chemical lithiation. The phase transition ranged from 0.25 < x < 0.5 in Li
x
MoO3 upon chemical lithium insertion into α-MoO3. The XRD lines of lithium inserted phase Li
x
MoO3 grew at the expense of the XRD lines of the pristine α-MoO3 as lithium ions were chemically inserted until the disappearance of lines related to α-MoO3. The electrochemical performance of the lithiated samples is improved in comparison with the starting material (non-lithiated
α-MoO3). 相似文献
143.
Rasmus Fonseca Glennie Helles Pawel Winter 《Journal of Mathematical Modelling and Algorithms》2011,10(4):357-369
One reason why ab initio protein structure predictors do not perform very well is their inability to reliably identify long-range
interactions between amino acids. To achieve reliable long-range interactions, all potential pairings of β-strands (β-topologies) of a given protein are enumerated, including the native β-topology. Two very different β-topology scoring methods from the literature are then used to rank all potential β-topologies. This has not previously been attempted for any scoring method. The main result of this paper is a justification
that one of the scoring methods, in particular, consistently top-ranks native β-topologies. Since the number of potential β-topologies grows exponentially with the number of β-strands, it is unrealistic to expect that all potential β-topologies can be enumerated for large proteins. The second result of this paper is an enumeration scheme of a subset of β-topologies. It is shown that native-consistent β-topologies often are among the top-ranked β-topologies of this subset. The presence of the native or native-consistent β-topologies in the subset of enumerated potential β-topologies relies heavily on the correct identification of β-strands. The third contribution of this paper is a method to deal with the inaccuracies of secondary structure predictors
when enumerating potential β-topologies. The results reported in this paper are highly relevant for ab initio protein structure prediction methods based
on decoy generation. They indicate that decoy generation can be heavily constrained using top-ranked β-topologies as they are very likely to contain native or native-consistent β-topologies. 相似文献
144.
Detection of the DeltaF508 mutation in the CFTR gene by means of time-resolved fluorescence methods.
S Kirschstein S Winter D Turner G L?ber 《Bioelectrochemistry and bioenergetics (Lausanne, Switzerland)》1999,48(2):415-421
A rapid recognition in the base sequence of nucleic acids is an important prerequisite toward the diagnosis of genetic diseases and their carrier states. We have developed a hybridisation method in which a fluorescently labeled oligonucleotide is used to detect point mutations in a target by a simple fluorescence lifetime analysis of the emission of the fluorescent label. We applied this method to detect the deltaF508 mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene in a model system and with biologically derived PCR product and discuss the potential generality of this method. 相似文献
145.
Kreusler und Traugott Winter 《Fresenius' Journal of Analytical Chemistry》1891,30(1):509-510
Ohne Zusammenfassung 相似文献
146.
Busayamas Pimpunchat Winston L. Sweatman Graeme C. Wake Wannapong Triampo Aroon Parshotam 《Applied Mathematics Letters》2009,22(3):304-308
We present a simple mathematical model for river pollution and investigate the effect of aeration on the degradation of pollutant. The model consists of a pair of coupled reaction–diffusion–advection equations for the pollutant and dissolved oxygen concentrations, respectively. The coupling of these equations occurs because of reactions between oxygen and pollutant to produce harmless compounds. Here we consider the steady-state case in one spatial dimension. For simplified cases the model is solved analytically. We also present a numerical approach to the solution in the general case. The extension to the transient spatial model is relatively straightforward. The study is motivated by the crucial problem of water pollution in many countries and specifically within the Tha Chin River in Thailand. For such real situations, simple models can provide decision support for planning restrictions to be imposed on farming and urban practices. 相似文献
147.
148.
J. Dorenbosch F. Udo J. V. Allaby U. Amaldi G. Barbiellini M. Baubillier F. Bergsma A. Capone W. Flegel F. Grancagnolo M. Jonker L. Lanceri M. Metcalf C. Nieuwenhuis J. Panman R. Plunkett C. Santoni K. Winter I. Abt F. W. Büsser H. Daumann P. D. Gall T. Hebbeker F. Niebergall P. Stähelin P. Gorbunov E. Grigoriev V. Kaftanov V. Khovansky A. Rosanov A. Baroncelli L. Barone B. Borgia C. Bosio M. Diemoz U. Dore F. Ferroni E. Longo L. Luminari P. Monacelli S. Morganti F. de Notaristefani L. Tortora V. Valente CHARM Collaboration 《Zeitschrift fur Physik C Particles and Fields》1989,41(4):567-589
A determination of sin2 θ w based on measurements of elastic scattering of muon-neutrinos and muon-anti-neutrinos on atomic electrons is described. These purely leptonic processes were studied using the CHARM calorimeter exposed to neutrino and antineutrino wide-band beams at the CERN super proton synchrotron. A total of 83±16 neutrino-electron and 112±21 antineutrino-electron events have been detected. From the measurement of the ratio of muon-neutrino and muon-antineutrino cross-sections a value of sin2 θ w =0.211±0.037 was obtained. 相似文献
149.
Tim Kemmitt Graeme J. Gainsford Najeh I. Al‐Salim 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(2):m42-m43
The title compound, octa‐tert‐butoxybis[μ3‐2,2′‐(N‐methylimino)diethanolato]di‐μ‐oxo‐tetratitanium(IV), [Ti2O{(OCH2CH2)2(NCH3)}{(CH3)3CO}4]2 or [Ti4(C5H11NO2)2(C4H9O)8O2], lies about an inversion centre, and displays the less usual zigzag configuration. One O atom of the N‐methyldiethoxoamine ligand bridges the symmetry‐related Ti atoms, while the other bridges the two independent Ti atoms, with the N atom binding to give a facial configuration. Four tBuO− ligands and a bridging oxide complete the respective five‐ and sixfold coordination of the two Ti atoms. The Ti—O bond lengths range in a self‐consistent fashion from 1.7624 (17) to 2.0878 (18) Å, while the Ti—N bond length is 2.374 (2) Å. 相似文献
150.