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161.
Hohnholz D MacDiarmid AG Sarno DM Jones WE 《Chemical communications (Cambridge, England)》2001,(23):2444-2445
In-situ deposited thin films of the conducting polymer poly-3,4-ethylenedioxythiophene (PEDOT) have been prepared on hydrophilic and hydrophobic substrates and characterized by UV-Vis spectroscopy, atomic force microscopy and resistivity measurements. 相似文献
162.
163.
The energy levels of a series of para substituted N,N-dimethylanilines p-MHnMe3?n C6H4NMe2 (n = 0?3, M = C or Si) for the ground and lower lying excited states have been determined in acetonitrile solution. The levels for the carbon compounds are all slightly destailized relative to N,N-dimethylaniline and the effects are rather insensitive to n. The stabilizations produced by silicon substituents on all levels are markedly affected by silicon's substituents, showing increasing perturbations with increasing n. It is concluded that variations in the interaction of the σ* system of the silyl substituent with the aniline π system, and not d orbital interactions, account for the trends observed. 相似文献
164.
Jones SC Hascall T Barlow S O'Hare D 《Journal of the American Chemical Society》2002,124(39):11610-11611
The bimetallic complexes [M(CO)(3)](2)(mu:eta(5):eta(5)-Pn) (Pn = pentalene, C(8)H(6); M = Mn, Re) have been synthesized and characterized crystallographically; the Mn compound was isolated as solely the anti-isomer, while the Re analogue was formed as a mixture of anti- and syn-isomers. [Mn(CO)(3)](2)(mu:eta(5):eta(5)-Pn) may be reduced chemically to its mono- and dianions; the mixed-valence Mn(I)/Mn(0) monoanion is shown by ESR, vibrational, and electronic spectroscopies to be a Robin-Day class III system with an exceptionally large electronic coupling between the metal centers. 相似文献
165.
Summary The relative partial molal thermodynamic functions
1
and
have been derived from reported experimental light scattering and calorimetric measurements on micellar solutions ofn-dodecyltrimethylammonium bromide. It is shown that the magnitudes of the thermodynamic functions are considerably larger than can be accounted for by the interaction of the electrical double layers surrounding the micelles. Possible enthalpy changes arising from a change in micelle shape, size and degree of dissociation on dilution are discussed.
Zusammenfassung Die relativen molaren thermodynamischen Partialfunktionen , andS 1wurden abgeleitet aus Literaturwerten von Lichtstreuungsmessungen und kalorimetrischen Untersuchungen an mizellaren Lösungen vonn-Dodecyltrimethylammoniumbromid. Es wird gezeigt, daß die Zahlenwerte der thermodynamischen Funktionen erheblich größer sind als von der Wechselwirkung der elektrischen Doppelschichten zu erwarten ist, die die Mizellen umgeben. Mögliche Enthalpieänderungen, die sich aus Änderungen von Größe, Gestalt und Dissoziationsgrad bei Verdünnung herleiten, werden diskutiert.相似文献
166.
Douglas O. Spry Anita R. Bhala Wayne A. Spitzer Noel D. Jones John K. Swartzendruber 《Tetrahedron letters》1984,25(24):2531-2534
The major product from the thermolysis and photolysis of C(3)-azido cephem 2 is the ring expanded 1,4,6-thiadiazepine azetidinone. 相似文献
167.
Santos E Schühle DT Jones H Schmickler W 《Langmuir : the ACS journal of surfaces and colloids》2005,21(14):6406-6421
The nonlinear optical properties of self-assembled monolayers obtained from bonding two different alpha-functionalized terthiophenes (alpha-T3) to (111) silver electrode surfaces have been investigated using second harmonic generation (SHG). The two (alpha-T3) compounds used were functionalized with alkane chains of different lengths (C8 and C4), and each was terminated with a thiol anchoring group. A nitrile group was attached to the terminal thiophene ring of the (alpha-T3) compound with the C4 chain. The orientation of the polarization of the incident beam was changed systematically and gradually between "p" and "s" orientation and the SH signal (isotropic and anisotropic contributions) analyzed in both directions ("P" and "S"). The symmetry of the system was reduced by the presence of the adlayers from C3v to C3. The dependence on the applied potential and the incident wavelength has also been studied. The relative magnitudes and phases of the various second-order tensor elements have been estimated and compared with the values for a bare surface. A resonance process in the (alpha-T3) pi moiety has been investigated, and from this, the effective "band-gap" energies of the organic semiconductor SAMs (i.e., the energy difference between the pi-pi bands) have been estimated. 相似文献
168.
Charles P. Casey William D. Jones Stephen G. Harsy 《Journal of organometallic chemistry》1981,206(3):C38-C42
The reaction of (η5-C5H5)W(CO)2(NO), 6W, with P(CH3)3 proceeds rapidly at 25°C to give (η5-C5H5)W(CO)(NO)[P(CH3)3], 7W. The rate of formation of 7W was found to be 4.48 × 10?2M?1 [6W] [P(CH3)3] at 25.0°c in THF. In neat P(CH3)3 at ?23°C, 6W is converted to (η1-C5H5)W(CO)2(NO)[P(CH3)3]2, 8W. In dilute solution, 8W decomposes to initially give a 2:1 mixture of 6W and 7W. The mixture is then converted to 7W. The reaction of (η5-C5H5)Mo(CO)(NO), 6Mo, with P(CH3)3 is 6.1 times faster than that of the tungsten analog. 相似文献
169.
170.
Each lattice in Rd determines a sequence of Brillouin zonesBn, fundamental regions for bounded by Bragg hyperplanes; forexample B1 is the Dirichlet region. Basic geometric and topologicalproperties of these zones are established, and we obtain asymptoticestimates (valid for almost all ) for (n) = , where L(n) is the number of connected componentsof the interior of Bn (called Landsberg subzones). Fermi surfacesare also briefly described. 相似文献