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141.
Nava Harubi Mordechai Shechter Abraham Subotnik 《European Journal of Operational Research》1979,3(4):296-307
The paper proposes an adaptive pricing mechanism which allocates computer resources among the different consumers in an economically efficient manner. Users are charged a unit price designed to reflect the marginal congestion load each imposes upon the system. Some of the more common allocation schemes are described briefly followed by a discussion of the desirable properties of an efficient allocative system. These properties are incorporated into a model of a computer facility, and a number of propositions regarding the behavior of this model are proposed. In order to test empirically the behavior of this system under conditions approximating those which would prevail in an actual computer center, the pricing mechanism was analyzed by a simulation model of a computer center, using data obtained from a survey of customers at the computer center of a university (Technion, Israel Institute of Technology at Haifa, Israel). A few suggestions regarding the implementation of the proposed pricing policy conclude the paper. 相似文献
142.
The effect of adsorption on the EELS of the tungsten (100) surface plane, for loss energies in the range of 2–25 eV, is investigated for a series of adsorbates (i.e. O2, N2, NO, CO and H2). Low-lying sharp structures observed in the energy loss spectra seem to be associated with prominent structures in the local surface density of states. A growth of a peak at a loss energy of about 7.5 eV, observed after exposing the surface to any one of the gases studied, is attributed to the breakdown of optic-like selection rules by the adsorption process. The effect of adsorption on the various surface plasmon peaks seems to be adsorbate-specific. 相似文献
143.
M. Bishari G. Cohen-Tannoudji H. Navelet R. Peschanski 《Zeitschrift fur Physik C Particles and Fields》1982,14(1):7-20
We derive a theoretical explanation of the similarities which have been experimentally observed between final state distributions in soft processes (K ? p interactions andpp collisions at ISR) and hard processes (e + e ? annihilations and deep inelastic scattering). The theoretical framework is the correspondence between QCD and dual topological unitarization (DTU), which expresses confinement as the equivalence of the hadron and parton bases to account for unitarity. Starting from the interpretation of the zero handle topology in DTU in terms of the naive quark parton model, we show how to characterize gluons in the hadron basis: primordial gluons are associated with the one handle topology, and the cascading of hard gluons is related to the sum of all higher topologies in DTU. We get this way a QCD interpretation of the reggeon calculus which is the theoretical framework of soft hadronic processes at asymptotic energies. 相似文献
144.
M. Paul A. Marinov J. Burde Ch. Drory J. Lichtenstadt S. Mordechai E. Navon 《Nuclear Physics A》1977,289(1):94-108
The 44Ca(d, α)42K reaction was studied at a bombarding energy of 11 MeV using a broadrange magnetic spectrograph and solid-state detectors. About thirty energy levels were identified in 42K, up to an excitation energy of 3.5 MeV. Excitation functions corresponding to some of the low-lying energy states of 42K were measured in the incident energy range from 10.4 to 11.6 MeV. Angular distributions of the α-particle groups corresponding to the excitation of about twenty energy levels in 42K have been measured. DWBA calculations were performed and L-values for most of the above transitions were deduced. The results were compared with previous information and possible spin and configuration assignments are proposed for some of the states. Centroids of states interpreted as belonging to the (1d?1)p (1f3)n, (2s?1)p (1f3)n and the (1d?1)P (1d?1 1f4)n configurations were found to be in good agreement with calculations based on the weak-coupling model. 相似文献
145.
Irradiation of dissociating cyclopentadienone-dimers (2 b, c, e) results in formation of two types of cage-products (5 and 8) in very low quantum yields and good, but wavelength and phase dependent chemical yields. Both processes are intramolecular, for 2b this was shown using isotopic labeling and massspectrometric techniques. Sensitization and quenching experiments indicate that triplet states are involved The mechanistic pathways are discussed. The cyclopentadienones(1 b,c,e) were isolated for the first time and irradiation of 1b in the solid gave exclusively the symmetric cage (8b) 相似文献
146.
The energy levels of 74As have been studied using the 73Ge(3He, d)74As reaction at an incident energy of 17 MeV. The overall energy resolution was 30 keV. Twenty-five levels in 74As were identified up to 2.2 MeV excitation energy and angular distributions were measured in the interval to . Spectroscopic strengths and lp values have been extracted for many of the transitions by means of a distorted-wave analysis of the differential cross sections. A comparison with the 75As(p, d) data suggests the presence of several unresolved doublets in 74As. 相似文献
147.
Mordechai Bixon 《Chemical physics》1982,70(3):199-206
It is demonstrated that in a dense medium the molecular stable states are the localized Born—Oppenheimer (LBO) states. The reason for this phenomenon 相似文献
148.
149.
Mordechai Lewin 《Israel Journal of Mathematics》1974,18(4):345-347
It is shown that a graphG has all matchings of equal size if and only if for every matching setλ inG, G\V(λ) does not contain a maximal open path of odd length greater than one, which is not contained in a cycle. (V(λ) denotes the set of vertices incident with some edge ofλ.) Subsequently edge-coverings of graphs are discussed. A characterization is supplied for graphs all whose minimal covers
have equal size. 相似文献
150.
A graph-theoretic approach is used to characterize (0,1)-matrices which are inverses of M-matrices. Our main results show that a (0,1)-matrix is an inverse of an M-matrix if and only if its graph induces a partial order on its set of vertices and does not contain a certain specific subgraph. 相似文献