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81.
82.
G. Molnár H. Ohm G. Lhersonneau K. Sistemich 《Zeitschrift für Physik A Hadrons and Nuclei》1988,331(1):97-98
A value of 84 ± 44 ps has been established for the half-life of the first 3? state of96Zr, using the centroid shift method. It is shown that the corresponding large electric octupole transition strength is in accordance with systematics, suggesting largest octupole collectivity when both the 1g9/2 Proton and 1h11/2 neutron orbitals are nearly empty due to the Z=40, N=56 double subshell closure. 相似文献
83.
We describe the general form of bijective maps on the space of all Hilbert space effects or all observables on a finite dimensional
space which preserve the spectral order in both directions.
The first author was supported by the Hungarian National Foundation for Scientific Research (OTKA), Grant No. T043080, T046203,
and the second author was partially supported by a grant from the Ministry of Science of Slovenia. Both authors were supported
by a joint Hungarian-Slovene grant, Reg. No. SLO-5/05. 相似文献
84.
E. Molnár P. L. Erdős A. Ádám Gy. Béda Zs. Páles 《Periodica Mathematica Hungarica》1989,20(4):307-311
85.
86.
87.
A. Borella A. Moens P. Schillebeeckx R. Van Bijlen G. L. Molnár T. Belgya Zs. Révay L. Szentmiklósi 《Journal of Radioanalytical and Nuclear Chemistry》2005,265(2):267-271
Summary The total capture cross section of 209Bi was determined at the cold neutron beam PGAA-NIPS facilities at the Budapest Neutron Centre. The measurements were performed using a coaxial HPGe detector with Compton suppression. The total and partial gamma-ray production cross sections were deduced relative to the 14N(n,γ) partial gamma-ray production cross section. By using a bismuth nitrate stoichiometric compound as the sample, we excluded various systematic uncertainties. The total capture cross section is in very good agreement with the compilation of Mughaghab, but is slightly lower than the most recent value determined at the high flux reactor of the ILL in Grenoble, France. We also performed measurements using a 0.5 mm thin Bi metal disc. The relative intensities determined from the Bi disc and the compound samples are in good agreement. 相似文献
88.
The thermal stability of heteropoly acids of the Keggin type (H4[SiMo12O40], H3[PMo12O40], H4[SiW12O40] and H3[PW12O40]), being important new catalytic materials, was studied by DSC. Two groups of signals were observed: the low temperature
endothermic peak group belongs to the water content, while the high temperature one is exothermic and indicates the thermal
decomposition of the acids. The effect of microwave irradiation on the target compounds was also studied. The emphasis, however,
was placed on the characterization of the water content of the acids. Several types of water can be classified and DSC curves
provide additional information to explain the differences in the catalytic behavior. The study of the effect of heat treatment
and the subsequent water absorption of the acids provided additional unique information concerning the pseudoliquid phase
in the secondary structure of heteropoly acids.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
89.
A simple method is presented for the determination of the available lysine residues of proteins. The sample is titrated directly with 0.05 or 0.1 M perchloric acid in anhydrous acetic or propionic acid to a potentiometric end-point. The titration is repeated after acylation of the sample. The difference between the two basicity values gives the available lysine content of the proteins. Results are provided for the available lysine contents of bovine serum albumin, human γ-globulin, β-casein, soya bean meals meat meal and milk protein; in most cases, they agree closely with literature data obtained by other methods. The standard error for the procedure is <3.9%. 相似文献
90.
The stability and characteristics of the C6-C8 n-aliphatic and phenylethylamines have been investigated as their o-phthaldialdehyde (OPA)/3-mercaptopropionic acid, OPA/N-acetyl-L-cysteine, OPA/2-mercaptoethanol and OPA/ethanethiol derivatives. Stoichiometric studies have been followed by photodiode array and fluorescence detection, simultaneously, while the composition of derivatives was confirmed by on line HPLC-electrospray ionization (ESI)-MS measurements. All four amines having in their original structure the NH2-CH2- moiety in accordance with the C1-C4 aliphatic, mono and diamines and amino acids of the same structure--furnished more than one OPA derivative: their initially formed isoindoles transform to further ones. Depending on the composition of the OPA reagents and on the pH of derivatizations different type of transformed species have been identified, in various proportions. Applying the OPA/SH additive reagent in the molar ratio of 1/3, favors the formation of one additional OPA molecule-containing isoindole, while using the OPA/SH additive (1/50) reagent resulted in the formation of one additional SH additive-containing species, identified and measured at the first time by HPLC. Transformation rate and stability of derivatives proved to be associated with the composition of the OPA reagent, with the type of the SH additive, with the pH of derivatizations, and, in selected cases also with the chain length of the amine. Results of stoichiometric and mechanism studies have been utilized to define optimum analytical conditions. 相似文献