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31.
The force constants, Coriolis coupling constants and mean amplitudes of vibration at 0, 298.16 and 500 K for GaF63?FeF63? have been reported for the first time employing recent vibrational data. The results are discussed in the light of available information. 相似文献
32.
The authors present six general integral formulas (four definite integrals and two contour inegrals) for theH-function of several complex variables, which was introduced and studied in a series of earlier papers by H. M. Srivastava and R. Panda (cf., e.g., [25] through [29]; see also [14] through [18], [20], [24], [32], [34], [35], [37], and [38]). Each of these integral formulas involves a product of the multivariableH-function and a general class of polynomials with essentially arbitrary coefficients which were considered elsewhere by H. M. Srivastava [21]. By assigning suiatble special values to these coefficients, the main results (contained in Theorems 1, 2 and 3 below) can be reduced to integrals involving the classical orthogonal polynomials including, for example, Hermite, Jacobi [and, of course, Gegenbauer (or ultraspherical), Legendre, and Tchebycheff], and Laguerre polynomials, the Bessel polynomials considered by H. L. Krall and O. Frink [9], and such other classes of generalized hypergeometric polynomials as those studied earlier by F. Brafman [3] and by H. W. Gould and A. T. Hopper [8]. On the other hand, the multivariableH-functions occurring in each of our main results can be reduced, under various special cases, to such simpler functions as the generalized Lauricella hypergeometric functions of several complex variables [due to H. M. Srivastava and M. C. Daoust (cf. [22] and [23])] which indeed include a great many of the useful functions (or the products of several such functions) of hypergeometric type (in one and more variables) as their particular cases (see,e. g., [1], [10] and [39]). Many of the aforementioned applications of our integral formulas (contained in Theorems 1, 2 and 3 below) are considered briefly. Further usefulness of some of these consequences of Theorems 1 and 2 in terms of the classical orthogonal polynomials is illustrated by considering a simple problem involving the orthogonal expansion of the multivariableH-function in series of Jacobi polynomials. It is also shown how these general integrals are related to a number of results scattered in the literature. 0261 0262 V 相似文献
33.
IR relative integrated intensities and half-widths of rocking (R) and wagging (W) bands of water in MnCl2 · 2H2O and CoCl2 · 2H2O are presented at 300 K and 120 K. Departure of observed intensity into DW/DR from those predicted by the fixed dipole model is attributed to anisotropic dynamic changes in dipole during these oscillations. A quantity representing the variation of this anisotropy between W and R oscillations is computed and its origin is discussed. An increase by 20% to 50% in both DW and DR on lowering the temperature has also been discussed. 相似文献
34.
P. Richards T. Prach S. C. Srivastava G. E. Meinken 《Journal of Radioanalytical and Nuclear Chemistry》1981,65(1-2):47-50
Preliminary results are described of a123Xe filled device to serve as a combination123I generator/iodination kit.123X was produced in the Brookhaven Linac Isotope Producer (BLIP) by the reaction127I(p, 5n)123Xe. The device consists of a small glass ampoule containing an internal glass breakseal and a flanged neck on which was crimped
a multi-injection type septum. The ampoule contained a hydrogen sulfide atmosphere to assure that the iodine generated from
the decay of the xenon was in the form of iodide. Following an adequate period for123Xe to decay (this period can be used for shipment), a needle is forced through the septum breaking the seal and residual gases
are pumped off. The123I in the form of iodide can then be rinsed from the ampoule with any desired solvent or reagent added directly to the device
to carry out an iodination in an enclosed environment. Preliminary results of both iodine recovery and iodinations have been
promising.
This research was supported by the US Department of Energy under Contract No. DE-ACO2-76CH0016. 相似文献
35.
S. P. Agrawal R. C. Aggrawal T. N. Srivastava 《Fresenius' Journal of Analytical Chemistry》1959,171(2):91-95
Summary p-Cresotic acid and its nitro, bromo, sulfo, acetyl, benzoyl and hydrazine derivatives and 5-methyl salicylic-o-aeetic acid have been used for the estimation of thorium and zirconium. The precipitates obtained have in all cases been ignited and weighed as oxides. These reagents have been found under suitable experimental conditions to effect the separation of Th as well as Zr from cerite earths. 相似文献
36.
Summary First and second order resistance coefficients between membrane matrix and permeant for the permeation of methanol, acetone and methyl ethyl ketone through pyrex and quartz membranes have been evaluated from the experimental data on electroosmotic effects. Analysis of the data shows that-the following non-linear relationP =R
11
J
v
+R
12
I +R
122
I
2[1] exists between pressure difference,P, and the fluxes and a linear relation =R
21
J
v
+R
22
I [2] expresses the dependence of potential difference,, on the fluxes. The first order cross resistance coefficients have been found to obey theOnsager's reciprocity relation. An attempt has been made to explain the occurrence of higher order resistance coefficients in terms of electrokinetic character of the membrane, permeant interface.
With 2 figures and 2 tables 相似文献
Zusammenfassung Die Widerstandskoeffizienten 1. und 2. Ordnung zwischen einer Membranmatrix und dem permeierenden Stoff wurden für die Permeation von Methanol, Aceton und Methyläthylketon durch Pyrex- und Quarz-Membranen auf Grund elektroosmotischer Effekte bestimmt. Die Auswertung gibt die nichtlineare BeziehungP =R 11 J v +R 12 I +R 122 I 2 [1] zwischen der Druckdifferenz und dem Fließen; die lineare Beziehung =R 21 J v +R 22 I [2] beschreibt die Abhängigkeit der Potentialdifferenz vom Fließen. Die gekreuzten Widerstandskoeffizienten 1. Ordnung gehorchen dem ReziprozitätsgesetzOnsager. Das Vorkommen von Widerstandskoeffizienten höherer Ordnung wird versuchsweise auf den elektrokinetischen Charakter der Membran-Grenzfläche zurückgeführt.
With 2 figures and 2 tables 相似文献
37.
K. C. Srivastava 《中国化学会会志》1974,21(3):163-166
A new, sensitive spectrophotometric method for the determination of palladium(II) with methylthymol blue has been developed. The palladium methylthymol blue complex has an absorption maximum at 530 nm. The colour reaction has a sensitivity of 0.005 µg of palladium/cm2 and obeys Beer's Law over the range 0.4 to 3.24 ppm of palladium. The effects of concentration of perchloric acid, reagent, heating, stability of colour and diverse ions have been investigated. The ratio of metal: ligand in the complex is 1:1 and the formation constant was calculated to be 1.18×104. 相似文献
38.
39.
Summary The coagulation concentration for silver iodide sol, both in presence of pyridine and dioxane, increases for mono- and bivalent
coagulating electrolyte. In presence of a mixture of pyridine and dioxane in equal volume, the coagulation concentration assumes
an intermediate value, which is nearer to dioxane. However, in presence of dioxane more bivalent electrolyte is needed than
in presence of pyridine. If a bivalent coagulating electrolyte is added to a sol containing a mixture of pyridine and dioxane,
the amount of electrolyte required to coagulate is less than pyridine and greater than dioxane. Thus silver iodide sol is
more stable toward mono- and bivalent coagulating electrolytes. The degree of stabilization increases with the decrease of
the dielectric constant of the dispersing medium. The intermediate values for dioxane pyridine mixture is accountable by the
fact that dioxane acts as a solvent for pyridine. The PH value of the sol increases up to the coagulation point. Beyond this,
there is an abrupt decrease. When the particles settle down completely a rise in PH is again noted on the further addition
of electrolytes. The increase in the electrical conductance is more significant after coagulation. These changes have been
explained by adsorption of the ions and due to the release of ions from the electrical double layer.
Our thanks are due to Prof. R. C. Mehrotra for providing all the facilities for this work and to Prof. S. Ghosh of Allahabad University for helpful discussions. Thanks are also due to the University Grants Commission, Government of India, for the award of a research scholarship to one of us (V. K. S.). 相似文献
Zusammenfassung Die Koagulationskonzentration für Silberjodidsol in Gegenwart von Pyridin und Dioxan steigt für ein- und zweiwertige Elektrolyte an. In Gegenwart einer Mischung zu gleichen Volumen erh?lt man mittlere Werte, n?her denen zu Dioxan. Für Koagulation in Gegenwart von Dioxan ist jedoch mehr zweiwertiger Elektrolyt notwendig als in Gegenwart von Pyridin. Bei Koagulation mit zweiwertigem Elektrolyt verbraucht ein Sol mit der Mischung von Pyridin und Dioxan weniger als für Pyridin und mehr als für Dioxan. Daher ist das Silbersol gegenüber ein- und zweiwertigen Elektrolyten stabiler. Der Grad der Stabilisierung w?chst mit abnehmender Dielektrizit?tskonstante des Dispersionsmediums. Die Zwischenwerte der Dioxan-Pyridin-Mischungen lassen sich verstehen durch die Tatsache, da? Dioxan als L?sungsmittel für Pyridin wirkt. Der PH-Wert des Sols w?chst bis zum Koagulationspunkt, darüberhinaus erfolgt ein steiler Abfall. Wenn die Teilchen vollst?ndig absetzen, ist bei weiterer Zugabe von Elektrolyt ein erneuter Anstieg im PH feststellbar. Der Anstieg der elektrolytischen Leitf?higkeit wird nach der Koagulation ausgepr?gter. Diese ?nderungen lassen sich durch Ionenadsorption und Freiwerden von Ionen aus der elektrischen Doppelschicht erkl?ren.
Our thanks are due to Prof. R. C. Mehrotra for providing all the facilities for this work and to Prof. S. Ghosh of Allahabad University for helpful discussions. Thanks are also due to the University Grants Commission, Government of India, for the award of a research scholarship to one of us (V. K. S.). 相似文献
40.