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71.
Summary On small columns filled with the inorganic cation-exchanger zirconium phosphate, Zn2+-Cd2+ were quantitatively and Ni2+-Co2+ partly separated. The exchanger was in the NH4+ form, and 0.5–4N NH4Cl served as eluent. With the exchanger in the H+ form, U02
2+ was separated from bivalent cations and ferric iron by stepwise elution with 0.1, 0.5 and 4N HCl solutions.
Zusammenfassung An kleinen Säulen des anorganischen Kationenaustauschers Zirkoniumphosphat wurden Zn2+ und Cd2+ quantitativ, Ni2+ und Co2+ teilweise getrennt. Der Austauscher lag in der NH4+-Form vor, 0,5-bis 4-n Ammoniumchlorid diente als Eluent. Mit der H+-Form des Austauschers wurde UO2 2+ von zweiwertigen Kationen und von Fe3+ durch schrittweise Elution mit 0,1-, 0,5- und 4-n Salzsäure getrennt.
Résumé On a séparé Zn2+-Cd2+ quantitativement et Ni2+-Co2+ partiellement sur de petites colonnes remplies de phosphate de zirconium comme échangeur minéral cationique. L'échangeur se trouvait sous forme NH4+ et l'on a pris NH4Cl 0,5-4N comme éluant. Avec l'échangeur sous forme H+, on a séparé UO2 2+ des cations bivalents et de l'ion ferrique par élution graduelle avec des solutions chlorhydriques 0,1, 0,5 et 4N.相似文献
72.
Tomislav P. Živković 《Journal of mathematical chemistry》2002,32(1):39-71
Interaction of quantum system S
a
described by the generalised × eigenvalue equation A|
s
=E
s
S
a
|
s
(s=1,...,) with quantum system S
b
described by the generalised n×n eigenvalue equation B|
i
=
i
S
b
|
i
(i=1,...,n) is considered. With the system S
a
is associated -dimensional space X
a
and with the system S
b
is associated an n-dimensional space X
n
b
that is orthogonal to X
a
. Combined system S is described by the generalised (+n)×(+n) eigenvalue equation [A+B+V]|
k
=
k
[S
a
+S
b
+P]|
k
(k=1,...,n+) where operators V and P represent interaction between those two systems. All operators are Hermitian, while operators S
a
,S
b
and S=S
a
+S
b
+P are, in addition, positive definite. It is shown that each eigenvalue
k
i
of the combined system is the eigenvalue of the × eigenvalue equation
. Operator
in this equation is expressed in terms of the eigenvalues
i
of the system S
b
and in terms of matrix elements
s
|V|
i
and
s
|P|
i
where vectors |
s
form a base in X
a
. Eigenstate |
k
a
of this equation is the projection of the eigenstate |
k
of the combined system on the space X
a
. Projection |
k
b
of |
k
on the space X
n
b
is given by |
k
b
=(
k
S
b
–B)–1(V–
k
P})|
k
a
where (
k
S
b
–B)–1 is inverse of (
k
S
b
–B) in X
n
b
. Hence, if the solution to the system S
b
is known, one can obtain all eigenvalues
k
i
} and all the corresponding eigenstates |
k
of the combined system as a solution of the above × eigenvalue equation that refers to the system S
a
alone. Slightly more complicated expressions are obtained for the eigenvalues
k
i
} and the corresponding eigenstates, provided such eigenvalues and eigenstates exist. 相似文献
73.
J. Jureta S. Cvejanović M. Kurepa D. Cvejanović 《Zeitschrift für Physik A Hadrons and Nuclei》1982,304(2):143-153
A high resolution electron impact threshold spectroscopy technique was used to examine the excitation of Cl2 in the 2–14 eV region. This study complements previous photon absorption and emission measurements, because it is capable of detecting transitions which are optically forbidden. In the region up to 7.5 eV, broad dissociative structures are correlated with optically active valence states, although relative intensities in the threshold spectrum differ considerably and indicate a substantial contribution from the optically forbidden transitions. At 7.46 eV a series of 5 equidistant sharp peaks is detected and interpreted as arising from the2 π g Feshbach resonance, which differs from the ground state positive ion Cl 2 + by a pair of Rydberg electrons: (4sσ)2. The decay channels responsible for the appearance of the resonance in a threshold spectrum are discussed and it is suggested that they include several valence states of the (2431) and (2341) configurations, whose potential energy curves cross the Cl 2 ? ,2πg curve in the region of energy at which the resonance state is formed. At higher incident electron energies and up to ionisation, Rydberg states predominate, starting with (2430) 4s3,1 π g states detected for the first time. The absence of broad peaks above 8 eV and the irregular appearance of Rydberg bands is consistent with the strong Rydberg-valence configuration mixing proposed by Peyerimhoff and Buenker. Where our resolution permits comparison, good general agreement is found with recent synchrotron radiation absorption measurements of optically allowed transitions. 相似文献
74.
Zusammenfassung Die analytische Bestimmung der Metalle, des Dipyridyls und der Chloride in Oxo-chloro-alkoxo-dipyridyl-Komplexverbindungen des Niobs und Tantals wurde beschrieben. Eine modifizierte Methode der Dipyridylanalyse, wie auch der Chloridbestimmung in Gegenwart von Dipyridyl wurde angegeben. Die radiometrische Metallbestimmung in Extraktionsverbindungen von Niob und Tantal mit Di-oktyl-methylenbis-phosphonsäure wurde dargelegt.
Vorgetragen beim Symposium für analytische Chemie in Graz, 29. September bis 1. Oktober 1965. 相似文献
Summary The analytical determination of metals, dipyridyl and chlorides in oxochloro-alkoxo-dipyridyl complex compounds of niobium and tantalum is described. A modified procedure of the dipyridyl analysis and also of the determination of chloride in the presence of dipyridyl is given. The radiometric determination of the metals in extraction compounds of niobium and tantalum with di-octyl-methylene-bis-phosphonic acid is discussed.
Résumé On décrit le dosage des métaux, du dipyridyle et des chlorures dans les composés complexes oxo, chloro, alcoxo, dipyridyle, du niobium et du tantale. On indique une méthode modifiée pour le dosage de dipyridyle ainsi que pour la détermination des chlorures, en présence de dipyridyle. On décrit le dosage radiométrique des métaux dans les produits d'extraction du niobium et du tantale par l'acide di-octyl-méthylène-bis-phosphonique.
Vorgetragen beim Symposium für analytische Chemie in Graz, 29. September bis 1. Oktober 1965. 相似文献
75.
A new catalytic reaction is proposed and a kinetic method developed for the determination of ultramicro amounts of Cu(II) on the basis of its catalytic activity in oxidation of the 2-thiosemicarbazone of sodium 1,2-naphthoquinone-4-sulphonate by hydrogen peroxide in the presence of ascorbic acid. Under optimal conditions the sensitivity of the method is 0.25 ng/ml. The relative error is 4.8-18.2% for the concentration range 5-0.8 ng/ml. Most foreign ions do not change the rate of the catalysed reaction. Co(2+) and I(-) catalyse the reaction, Ni(2+) extensively inhibits it, and in the presence of EDTA only the uncatalysed reaction takes place. 相似文献
76.
We obtain sharp estimates for sums of reciprocals and sums of quotients of certain non-negative integer-valued additive arithmetical functions.Research financed by the Mathematical Institute of Belgrade and Republika Zaj. of Serbia 相似文献
77.
B. Pavković 《Archiv der Mathematik》1979,32(1):509-512
Ohne Zusammenfassung 相似文献
78.
L. N. Latysheva A. A. Bergman N. M. Sobolevsky R. D. Ilić 《Physics of Atomic Nuclei》2013,76(4):464-468
Lead slowing-down (LSD) spectrometers have a low energy resolution (about 30%), but their luminosity is 103 to 104 times higher than that of time-of-flight (TOF) spectrometers. A high luminosity of LSD spectrometers makes it possible to use them to measure neutron cross section for samples of mass about several micrograms. These features specify a niche for the application of LSD spectrometers in measuring neutron cross sections for elements hardly available in macroscopic amounts—in particular, for actinides. A mathematical simulation of the parameters of SVZ-100 LSD spectrometer of the Institute for Nuclear Research (INR, Moscow) is performed in the present study on the basis of the MCNPX code. It is found that the moderation constant, which is the main parameter of LSD spectrometers, is highly sensitive to the size and shape of detecting volumes in calculations and, hence, to the real size of experimental channels of the LSD spectrometer. 相似文献
79.
80.
Predrag M. Tekić Jelena B. Rađenović Svetlana S. Popović 《International Journal of Computational Fluid Dynamics》2013,27(9):383-390
In this article, the lattice Boltzmann method is employed in order to explore incompressible fluid flow inside a two-sided lid-driven staggered cavity. Results of the lattice Boltzmann simulation for antiparallel motion of lids are compared with the data from existing literature. For parallel motion of lids, the characteristics of flow pattern for a variety of Re numbers (50–3200) are presented. An asymmetric steady-state flow pattern for parallel motion of lids is obtained. 相似文献