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801.
Finding signs of the classical-quantum border is a very important task of perennial interest. We show, using semiclassical
arguments, that the frontier between the classical and quantum domains can be characterized by recourse to idiosyncratic features
of a delimiter parameter associated with the concepts of i) noise) ii) Husimi distribution functions, iii) Wherl’s entropy,
and iv) escort distributions.
相似文献
802.
Patrícia Maria Berardo Gonalves Maia Campos Rodolfo Scarpino Barboza Franco Letícia Kakuda Gabriel Fernandes Cadioli Gabriela Maria DAngelo Costa Elodie Bouvret 《Molecules (Basel, Switzerland)》2021,26(16)
Collagen and its peptides are natural ingredients used in food supplements and nutricosmetics with the claim of providing benefits for skin health and beauty. In this context, the aim of the present study was to evaluate the clinical efficacy of oral supplementation with hydrolyzed fish cartilage for the improvement of chronological and photoaging-induced skin changes. A total of 46 healthy females aged 45 to 59 years were enrolled and divided into two groups: G1—placebo and G2—oral treatment with hydrolyzed fish cartilage. Measurements of skin wrinkles, dermis echogenicity and thickness, and morphological and structural characteristics of the skin were performed in the nasolabial region of the face before and after a 90-day period of treatment using high-resolution imaging, ultrasound, and reflectance confocal microscopy image analyses. A significant reduction in wrinkles and an increase of dermis echogenicity were observed after a 90-day period of treatment with hydrolyzed fish cartilage compared to the placebo and baseline values. In addition, reflectance confocal microscopy (RCM) image analysis showed improved collagen morphology and reduced elastosis after treatment with hydrolyzed fish cartilage. The present study showed the clinical benefits for the skin obtained with oral supplementation with a low dose of collagen peptides from hydrolyzed fish cartilage. 相似文献
803.
M. V. D’Angelo B. Semin G. Picard M. E. Poitzsch J. P. Hulin H. Auradou 《Transport in Porous Media》2010,84(2):389-408
The transport of fibers by a fluid flow is investigated in transparent channels modeling rock fractures: the experiments use
flexible polyester thread (mean diameter 280 μm) and water or a water–polymer solution. For a channel with smooth parallel walls and a mean aperture ā = 0.65 mm, both fiber segments of length ℓ = 20–150 mm and “continuous” fibers longer than the channel length have been used: in both the cases, the velocity of the
fibers and its variation with distance could be accounted for while neglecting friction with the walls. For rough self-affine
walls and a continuous gradient of the local mean aperture transverse to the flow, transport of the fibers by a water flow
is only possible in the region of larger aperture (ā ≲ 1.1 mm) and is of “stop and go” type at low velocities. With the polymer solution, the fibers move faster and more continuously
in high aperture regions and their interaction with the walls is reduced; fiber transport becomes also possible in narrower
regions where irreversible pinning occurred for water. In a third rough model with parallel walls and a low mean aperture
ā = 0.65 mm, fiber transport is only possible with the water–polymer solution. The dynamics of fiber deformations and entanglement
during pinning–depinning events and permanent pinning is analyzed. 相似文献
804.
The special theory of relativity teaches us that, although distinct inertial frames perceive the same dynamical laws, space and time intervals differ in value. We revisit the problem of time contraction using the paradigmatic model of a fast-moving laboratory within which a photon is emitted and posteriorly absorbed. In our model, however, the laboratory is composed of two independent parallel plates, each of which allowed to be sufficiently light so as to get kickbacks upon emission and absorption of light. We show that the lightness of the laboratory accentuates the time contraction. We also discuss how the photon frequency shifts upon reflection in a light moving mirror. Although often imperceptible, these effects will inevitably exist whenever realistic finite-mass bodies are involved. More fundamentally, they should necessarily permeate any eventual approach to the problem of relativistic quantum frames of reference. 相似文献
805.
Gianfranco Gambarelli Angelo Uristani 《Central European Journal of Operations Research》2009,17(4):433-460
This work links two research branches regarding cooperative games: multi-cameral games and a priori coalitions. Regarding
the former, many parliaments are based on a bicameral system where bills have to be approved by both chambers. The parties’
power indices are affected by it. In fact one certain political party for one certain coalition can be crucial in one chamber
and not in the other. Usually the problem can be solved by building a unified game, related to two or more chambers, where
the global power indices can be calculated. Concerning cohesion games, some coalitions among parties might be possible, but
have a low probability of materializing if the parties involved have very different ideologies. It is necessary to take this
into consideration when we compute the relative power indices. In this work, a model is built that takes into consideration
both topics. An automatic calculation algorithm is elaborated and is applied to the current situations in Belgium, the Czech
Republic, France, Italy, the Netherlands, Poland and Romania, considering the location of the parties on the left-right axis.
This model is then applied globally to the European Union. In this work the model is applied to Politics, but its applications
are not limited to that field. For instance, in Finance it can be applied to describe agreements for debt restructuring and
corporate mergers. 相似文献
806.
Maria Maddalena Cavalluzzi Angelo Lovece Claudio Bruno Alessia Catalano Alessia Carocci Carlo Franchini 《Tetrahedron letters》2010,51(40):5265-5959
A simple, convergent synthesis of the N-carbonyloxy β-d-glucuronide of mexiletine (sodium salt) in moderate yield is described. The compound is now available as an authentic reference standard for analytical studies, enabling more detailed investigation on the metabolism of mexiletine. 相似文献
807.
Aurora A Boiocchi M Dacarro G Foti F Mangano C Pallavicini P Patroni S Taglietti A Zanoni R 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(21):5535-5546
A new series of ligands, containing one (L1H(2)-L4H(2)) or two (L5H(4)-L6H(4)) 1,4,8,11-tetraaza-5,7-dione units and functionalized with a propargyl group on the C atom between the C=O moieties, has been synthesized. Protonation constants for the ligands and formation constants of their Cu(2+) complexes have been determined in water, and the coordination geometry of the complexes existing at various pH values has been investigated by coupled pH-metric and spectrophotometric titrations. Ligands capable of simple uptake of Cu(2+) with the formation of neutral, square-planar complexes containing the -2-charged diamino-diimido donor sets and ligands containing further coordinating groups (quinoline or pyridine) capable of single and double cation translocation have been investigated. The role of the substituents on the amino groups and the structural role played by the propargyl group have been examined as regards Cu(2+) complexation and translocation. In the double-translocating ligand L6H(4), when the two Cu(2+) ions move inside the diamino-diamido donor set, the slim propargyl group allows an unprecedented folding of the whole ligand with apical coordination of one pyridine to form a five-coordinate, square-pyramidal Cu(2+) ion. The crystal and molecular structures of this unusual [L6Cu(2)] complex have been determined by X-ray diffraction. Finally, oxidation of Cu(2+) to Cu(3+) has been studied by cyclic voltammetry in water, which revealed that the redox reaction occurs only when the copper cation is within the diamino-diimido compartment. Moreover, both functionalization of the primary amines with bulky substituents and apical coordination of Cu(2+) make access to the 3+ oxidation state more difficult and disrupt the reversibility of the electrochemical process. 相似文献
808.
Bacchi S Benaglia M Cozzi F Demartin F Filippini G Gavezzotti A 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(13):3538-3546
The arene-perfluoroarene stacking interaction was studied by experimental and theoretical methods. A series of compounds with different possibilities for formation of this recognition motif in the solid state were synthesized, and their crystal structures determined by single-crystal X-ray diffraction. The crystal packing of these compounds, as well as the packing of related compounds retrieved from crystallographic databases, were analyzed with quantitative crystal potentials: total lattice energies and the cohesive energies of closest molecular pairs in the crystals were calculated. The arene-perfluoroarene recognition motif emerges as a dominant interaction in the non-hydrogen-bonding compounds studied here, to the point that asymmetric dimers formed over the stacking motif carry over to asymmetric units made of two molecules in the crystal both for pure compounds and for molecular complexes; however, inter-ring distances and angles range from 3.70 to 4.85 A and from 5 to 21 degrees , respectively. Pixel energy partitioning reveals that whenever aromatic rings stack, the largest cohesive energy contribution comes from dispersion, which roughly amounts to 20 kJ mol(-1) per phenyl ring, while the coulombic term is minor but significant enough to make a difference between the arene-arene or perfluoroarene-perfluoroarene interactions on the one hand, and arene-perfluoroarene interactions on the other, whereby the latter are favored by about 10 kJ mol(-1) per phenyl ring. No evidence of special interaction which can be attributed to HF confrontation was recognizable. 相似文献
809.
We provide maximal time regularity properties for the solutions to a class of degenerate first-order integro-differential
Cauchy problems in a Banach space X. In particular, we show that an additional condition of space regularity on the data it suffices for restoring the loss of
time regularity which arises naturally when dealing with the degenerate case. 相似文献
810.
This paper deals with the equilibrium problem in nonlinear elasticity of hyperelastic solids under anticlastic bending. A three-dimensional kinematic model, where the longitudinal bending is accompanied by the transversal deformation of cross sections, is formulated. Following a semi-inverse approach, the displacement field prescribed by the above kinematic model contains three unknown parameters. A Lagrangian analysis is performed and the compressible Mooney-Rivlin law is assumed for the stored energy function. Once evaluated the Piola-Kirchhoff stresses, the free parameters of the kinematic model are determined by using the equilibrium equations and the boundary conditions. An Eulerian analysis is then accomplished to evaluating stretches and stresses in the deformed configuration. Cauchy stress distributions are investigated and it is shown how, for wide ranges of constitutive parameters, the obtained solution is quite accurate. The whole formulation proposed for the finite anticlastic bending of hyperelastic solids is linearized by introducing the hypothesis of smallness of the displacement and strain fields. With this linearization procedure, the classical solution for the infinitesimal bending of beams is fully recovered. 相似文献