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961.
Jacot-Guillarmod R. Adamczak A. Beer G. A. Bystritsky V. M. Czapliński W. Filipowicz M. Fujiwara M. C. Huber T. M. Kammel P. Knowles P. E. Kunselman A. R. Markushin V. E. Marshall G. M. Mulhauser F. Olin A. Petitjean C. Rivkis L. A. Stolupin V. A. Woźniak J. Zmeskal J. 《Hyperfine Interactions》1996,101(1):563-571
Hyperfine Interactions - Knowledge of the cross sections for scattering of µp, µd and µt on molecules of hydrogen isotopes is necessary not only for checking the algorithmic solution... 相似文献
962.
The polarized absorption spectra of eight dichroic dyes, alkyl derivatives of 4-amino-(N-ethylnaphthalimide) dissolved in the nematic liquid crystals 5CB and 6CHBT have been measured as a function of temperature. On the basis of these spectra, the guest order parameter has been evaluated. The influence of the alkyl chain length of the dye molecule on the molecular orientation has been examined. Moreover, the nematic-isotropic transition temperatures for the dye-liquid crystal mixtures have been determined. The experimental results have been compared in some detail with calculations made on the basis of the mean field theory for binary mixtures. 相似文献
963.
Dagmara Jacewicz Aleksandra Dąbrowska Agnieszka Łapińska Lech Chmurzyński 《Transition Metal Chemistry》2006,31(5):575-579
The cis-[Cr(phen)2(O2CO)]+ ion was prepared through the displacement of two molecules of water from the cis-[Cr(phen)2(OH2)2]3+ by the bidentate carbonate anion. It underwent two-phase hydrolysis reactions under acidic conditions (0.1 < [H+] < 2.7 m) at 5, 10, 15, 20 and 25 °C. Via slow carbonato chelate ring opening (first step k1slow) and a second fast decarboxylation(k2fast value). The first step was preceded by protonation of the coordinate bidentate carbonate ligand. The second step exhibited
no pH dependence, while k1slow values increased with acid concentration that suggested the presence of both protonated and deprotonated reactant species.
Based on these observations we have proposed a hydrolysis mechanism featuring H2O-induced ring-opening of the coordinate CO32− group in the first step k1slow followed by loss of CO32− from two intermediates, [Cr(phen)2(O2COH)]2+ (k1slow) and [Cr(phen)2(OH2)(O2COH)]2+ (k2fast). 相似文献
964.
Set-valued dynamic systems and random iterations of set-valued weaker contractions in uniform spaces
K. W?odarczyk C. Obczyński D. Wardowski 《Journal of Mathematical Analysis and Applications》2006,318(2):772-780
Set-valued weaker contractions in uniform, locally convex and metric spaces are defined and dynamic systems of such weaker contractions are studied. Conditions guaranteeing the convergence of generalized sequences of random iterations and iterations and the existence and uniqueness of endpoints of set-valued weaker contractions are established. Our definitions and results are new for set-valued maps in uniform, locally convex and metric spaces and even for single-valued maps. 相似文献
965.
V. A. Karnaukhov H. Oeschler A. Budzanowski S. P. Avdeyev V. V. Kirakosyan V. K. Rodionov P. A. Rukoyatkin A. V. Simonenko W. Karcz I. Skwirczyńska E. A. Kuzmin E. Norbeck A. S. Botvina 《Physics of Atomic Nuclei》2006,69(7):1142-1148
Thermal multifragmentation of hot nuclei is interpreted as the nuclear liquid-fog phase transition inside the spinodal region. The exclusive data for p(8.1 GeV) + Au collisions are analyzed within the framework of the statistical model SMM. It is found that the partition of
hot nuclei is specified after expansion to a volume equal to V
t = (2.6 ± 0.3)V
0. The freeze-out volume is found to be twice as large: V
f = (5 ± 1)V
0. The similarity between multifragmentation and ordinary fission is discussed.
The text was submitted by the authors in English. 相似文献
966.
Rafał Frański 《Journal of mass spectrometry : JMS》2004,39(3):272-276
The complexes of 2,5-disubstituted-1,3,4-oxadiazoles, namely 2,5-diphenyl-1,3,4-oxadiazole (1), 2,5-bis(2-pyridyl)-1,3,4-oxadiazole (2) and 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (3), with copper cation were studied by electrospray ionization mass spectrometry (ESI-MS). The ability of the compounds studied to form complexes with copper (under the ESI conditions) can be ordered as 2 > 1 > 3. The compounds studied tend to form both 1 : 1 and 2 : 1 chelate complexes with both copper(II) and copper(I). The complexes with copper(I) are formed in the ESI process. The influence of solvent polarity, solution flow-rate, counter ions (Cl−, NO3−, CH3COO−, SO42−, acetylacetonates) on the type of the ions observed was studied. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
967.
Marek J. Śmietański 《Numerical Algorithms》2006,41(3):219-238
A new version of finite difference approximation of the generalized Jacobian for a finite max function is constructed. Numerical
results are reported for the generalized Newton methods using this approximation. 相似文献
968.
A. Birczyński Z.T. Lalowicz A.M. Szymocha M. Punkkinen E.E. Ylinen A.H. Vuorimäki 《Chemical physics》2006
Deuteron spin–lattice relaxation is studied in 5% and 100% deuterated ammonium hexachlorostannate and perchlorate. The relaxation rate is observed to be independent of deuteration down to temperatures slightly lower than that of the maximum. At lower temperatures the rate of the 5% deuterated sample exceeds that of the 100% deuterated sample by four and two orders of magnitude in ammonium hexachlorostannate and perchlorate, respectively. The angular dependence of the deuteron relaxation rate in 5% deuterated ammonium hexachlorostannate at 6 K is explained in terms of existing models on quadrupolar relaxation. In 5% ammonium perchlorate one hydrogen equilibrium position, which lies on the preferred axis for 120° rotations, has a larger probability to be occupied by the deuteron of NH3D+ ions. The deuterons at the other positions are still performing rotational jumps about the preferred C3 axis and also about the other threefold axes, although at a slower rate. Such observations require a reconsideration of the relaxation process. A somewhat more general expression is derived for the relaxation rate, which agrees with the experimentally observed angular dependence for 5% deuterated ammonium perchlorate at 60 K. At lower temperatures the quadrupole coupling of the deuterons at the preferred axis may become practically time-independent. Then a significant contribution to the relaxation rate can be provided by the deuteron–proton magnetic dipolar interaction, which is still fluctuating fast via the rotation of the three protons about the axis through the stationary deuteron. 相似文献
969.
W. Sierpiński 《Monatshefte für Mathematik》1928,35(1):239-242
Sans résumé 相似文献
970.