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101.
Prabhu VM Vogt BD Wu WL Douglas JF Lin EK Satija SK Goldfarb DL Ito H 《Langmuir : the ACS journal of surfaces and colloids》2005,21(15):6647-6651
The depth profile of the counterion concentration within thin polyelectrolyte films was measured in situ using contrast variant specular neutron reflectivity to characterize the initial swelling stage of the film dissolution. We find substantial counterion depletion near the substrate and enrichment near the periphery of the film extending into the solution. These observations challenge our understanding of the charge distribution in polyelectrolyte films and are important for understanding film dissolution in medical and technological applications. 相似文献
102.
Baudry Y Pasini D Nishihara M Sakai N Matile S 《Chemical communications (Cambridge, England)》2005,(38):4798-4800
Voltage-sensitive blockage by ADP, ATP and phytate (IP6) demonstrates that active-site contraction toward the middle of newly synthesized rigid-rod beta-barrels provides a general strategy to rationally create and modulate the voltage sensitivity (and to increase the efficiency) of molecular recognition by synthetic multifunctional pores. 相似文献
103.
104.
Gianluca Nasini Lucio Merlini Giovanni Dario Andreetti Gabriele Bocelli Paolo Sgarabotto 《Tetrahedron》1982,38(18):2787-2796
The absolute configuration of the asymmetric carbons and the axial chirality of the natural mold metabolite cercosporin (from .) have been established on the basis of X-ray analysis and chemical reactions. The results confirm the inherent dissymmetry of the perylenequinone ring, the twisting of which gives rise to the diastereoisomer isocercosporin. The energy barrier for the conversion of cercosporin into isocercosporin has been evaluated. 相似文献
105.
106.
Dario Graffi 《Annali di Matematica Pura ed Applicata》1960,50(1):379-387
Sunto Si dimostra, per le equazioni del moto dei fluidi, un teorema di unicità valido in domini illimitati, senza supporre condizioni
di convergenza all’infinito per la velocità.
Ad Antonio Signorini nel suo 70mo compleanno. 相似文献
107.
VRETENAR Dario 《中国科学:物理学 力学 天文学(英文版)》2010,(4)
The positive-parity single-neutron levels in an axially-deformed relativistic quadrupole Woods-Saxon potential are analyzed. Neutron states are obtained as the solutions of the corresponding single-particle Dirac equation, using the coupled-channels method in the coordinate space. The evolution of the levels close to the continuum threshold and, in particular, the occurrence of singleneutron resonant states as the functions of the axial deformation parameter 0 β 0.5, are examined using the eigenphase representation. Calculations are performed for different values of the radius of the potential (R/r 0 ) 3 , corresponding to a variation of the mass number A. 相似文献
108.
Dario Martelli James Sparks Shing-Tung Yau 《Communications in Mathematical Physics》2006,268(1):39-65
We show that the Reeb vector, and hence in particular the volume, of a Sasaki–Einstein metric on the base of a toric Calabi–Yau cone of complex dimension n may be computed by minimising a function Z on
which depends only on the toric data that defines the singularity. In this way one can extract certain geometric information for a toric Sasaki–Einstein manifold without finding the metric explicitly. For complex dimension n = 3 the Reeb vector and the volume correspond to the R–symmetry and the a central charge of the AdS/CFT dual superconformal field theory, respectively. We therefore interpret this extremal problem as the geometric dual of a–maximisation. We illustrate our results with some examples, including the Y
p,q
singularities and the complex cone over the second del Pezzo surface. 相似文献
109.
Biver T Lombardi D Secco F Tiné MR Venturini M Bencini A Bianchi A Valtancoli B 《Dalton transactions (Cambridge, England : 2003)》2006,(12):1524-1533
The macrocyclic polyamine 2,5,8,11,14-pentaaza[15]-[15](2,9)[1,10]phenanthrolinophane (neotetren) is studied in its ability to coordinate Cu(ii) even at very low pH values and to interact, as a metal complex, with DNA. The kinetics and equilibria for 1 : 1 and 2 : 1 metal-ligand complexes formation are studied by the stopped-flow method and UV spectrophotometry. Differently protonated complexes are formed, with rate constants much lower than that of water exchange at copper(II) and other Cu(II)/amine systems, this behaviour being ascribed to ring effects and intra-molecular hydrogen bonds. Concerning the DNA/copper(II)-neotetren complexes interaction, analysis of data suggests an intercalative mode of binding. The kinetic results for both DNA/CuL and DNA/Cu(2)L systems agree with the sequence D + S <-->D,S <-->DS where the metal complexes (D) react with the DNA sites (S) leading to fast formation of an externally bound form (D,S) which is converted into an intercalated complex (DS). A very slow process is also detected and ascribed to a conformational change in the polynucleotide secondary structure where the metal centre plays a crucial role. Chromatographic experiments demonstrate that both the investigated Cu(II)/L complexes are able to cleave DNA, but only in the presence of hydrogen peroxide. 相似文献
110.