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151.
152.
U. J. Schrewe E. Hagberg H. Schmeing J. C. Hardy V. T. Koslowsky K. S. Sharma 《Zeitschrift für Physik A Hadrons and Nuclei》1984,315(1):49-55
Neutron-deficient osmium and rhenium isotopes were produced by bombarding an enriched144Sm target with beams of27Al and28Si. Previously reported decay data concerning168,169,170Os were confirmed. Three newα groups, observed in the144Sm+27Al reaction, were assigned to the decay of166,167,168Re based on excitation functions,α-energy systematics and theoretical half-life predictions. Their decay properties are: $$\begin{gathered} {}^{166}\operatorname{Re} , E_\alpha = 5,372 (10) keV, T_{1/2} = 2.8 (3) s; \hfill \\ {}^{167}\operatorname{Re} , E_\alpha = 5,136 (8) keV, T_{1/2} = 6.1 (2) s and \hfill \\ {}^{168}\operatorname{Re} , E_\alpha = 4,894 (10) keV, T_{1/2} = 6.9 (8) s. \hfill \\ \end{gathered}$$ It is proposed that twoα groups, observed in the144Sm+28Si reaction, originate from isomeric states in168,169Re. Our measured data for the isomeric states are: $$\begin{gathered} {}^{168m}\operatorname{Re} , E_\alpha = 5,250 (10) keV, T_{1/2} = 6.6 (15) s and \hfill \\ {}^{169m}\operatorname{Re} , E_\alpha = 5,050 (10) keV, T_{1/2} = 12.9 (11) s. \hfill \\ \end{gathered} $$ 相似文献
153.
Hardy M Ouari O Charles L Finet JP Iacazio G Monnier V Rockenbauer A Tordo P 《The Journal of organic chemistry》2005,70(25):10426-10433
[structure: see text] 5-(Cholesteryloxyethoxyphosphoryl)-5-methylpyrroline N-oxide (5-ChEPMPO), a DEPMPO analogue bearing a cholesterol group on the phosphorus atom, has been prepared and used to trap peroxyl-, alkoxyl-, thiyl-, and carbon-centered radicals in organic solvent. The important steric hindrance in 5-ChEPMPO does not affect the properties of 5-ChEPMPO in comparison to DEPMPO for the spin trapping of an enantiopure linoleic acid hydroperoxide. The 5-ChEPMPO-OOL spin adduct was observed by ESR and confirmed by ESI-MS/MS experiments. The relaxation terms of the 5-ChEPMPO-lipid peroxyl spin adduct were compared with those of other peroxyl spin adducts, and it was shown that the cholesteryl group has only a weak influence on the exchange rate between adduct conformers. 相似文献
154.
K. Nyitrai F. Cser G. Csermely L. Füzes G. Samay G. Hardy 《European Polymer Journal》1978,14(7):467-474
The solid-, cholesteric- and liquid-state polymerizations of cholesteryl-vinyl-succinate (CVS) are studied. Only one of the three polymorphic modifications of CVS oligomerizes in the solid state into oligomers of degree in a homogeneous topochemical reaction. The rate of polymerization in the cholesteric state is lower than that in the liquid state at the same temperature. Kinetic constants were measured at 85° using benzoyl peroxide as initiator and the Banfield radical, giving Eoverall = 15.4, 36.4 kcal/mole?1; , (1/mole sec), ( kcal mole?1. The values refer to the liquid- and the cholesteric-state reactions, respectively. The average degree of polymerization is low in both cases (). It was concluded that the molecular weights are controlled by chain transfer and that the initiation reaction is mostly dependent on the phase where the reaction takes place. 相似文献
155.
156.
Gérald Perron Alain Hardy Jean-Claude Justice Jacques E. Desnoyers 《Journal of solution chemistry》1993,22(12):1159-1178
Ethylammonium nitrate (ETAN), a low melting fused salt which is completely miscile in water and in many non-aqueous solvents,
was used as a model system for the study of concentrated non-aqueous electrolyte solutions. Acetonitrile (AN) was chosen as
a representative aprotic solvent. Some data were also obtained for water as solvent. The properties investigated over the
whole mole fraction range, many as a function of temperature, were solid-liquid phase diagram, volume, heat capacity, conductivity
and viscosity. Most properties in both solvents vary in a regular fashion over the whole mole fraction range and the properties
at high concentration rapidly tend to those of the molten salt. The apparent volumes and heat capacities vary linearly with
lnX2 over a large mole fraction range. There is evidence of significant association in AN (K
A
=1094 l-mol−) but not in water. The low concentration thermodynamic data were fitted with an association model using the above K
A
to obtain the partial molar quantities of ETAN at infinite dilution and in the associated state. These latter values are
of the same magnitude as the molar quantities of the molten electrolyte. 相似文献
157.
Trace amounts of substances have been related to iodine consumption monitored by chemiluminescence from the iodine-luminol system. Iodine titrations of sulphite and arsenic(III) have been carried out at levels of 1.0 x 10(-7) and 5.0 x 10(-8)M with a precision and error of better than 1% on a day-to-day basis. A calibrated standard of 1.8 ppm SO(2) in air was analysed with a precision of +/-1.2%, and an error of 0.9%. A rate method has been developed based on the reaction between iodine and penicillin G; a linear range from 10(-8) to 10(-7)M was found, the precision being +/-9%. 相似文献
158.
159.