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961.
The radially symmetrical small-angle scattering pattern (which would be obtained by the use of a direct beam having a point-like cross section) is in practice distorted, especially by the beam height. To eliminate this distortion the integration of a set of curves based on the derivative of the measured intensity distribution is required to derive the true radial intensity distribution. A rapid graphical method of plotting these curves is described and its accuracy is proved on an example. It is further shown that the radial intensity distribution can be determined in principle using the values of the measured curve instead of its derivative.
( ) . , . . . , .
  相似文献   
962.
As a base for the theory of moving striations a partial integro-differential equation (26) is derived from the equations of continuity (1), (2), the Laplace-Poisson equation (3) and relation (4) between the electric field and the temperature of the electrons. Apart from the processes necessary for the actual formation of striations according to [1] and for the amplification of the wave of stratification according to [2], the equation also includes the processes defining the Debye length of the electrons, the influence of the axial electric field and of its local deflections on the motion of current carriers and the direct influence of the deviations in concentration of the electrons on the rate of production of current carriers. In deriving the equation the main attention is paid to the physical sense of the mathematical operations applied. The general solution is found by the method of the two-sided Laplace transformation and is described by triple integral convolution (42).
I.
(1), (2), - (3) (4) (26). , , [1], , [2], , , . . (42).
  相似文献   
963.
The paper describes the principle of a detector with two opposite surface barriers and the experimental verification of its functioning. The detector permits double the effective depth to be attained on the material with a given bias voltage. The principle of opposite barriers also permits a reduction in the system of dE/dx andE detectors to one detector.
. . dE/dx E .


The authors thank A. Irra for carefully preparing the plates, K. Putz and J. imková for very effective help in measuring on the cyclotron and the members of of the cyclotron staff for their cooperation.  相似文献   
964.
The rocking curves of Ge (111), (220), (333) for CuK 1 radiation were measured by means of the triple-crystal diffractometer. Perfect silicon single crystals, cut parallel to the (111) plane were used in the monochromator part of the triple-crystal diffractometer. The results prove the suitability of such a monochromator for studying diffraction patterns.
. II
(rocking curves) (111), (220), (333) CuK 1 . , (111). .


In conclusion the authors thank A. Haruý for preparing the germanium single crystals and they are indebted to V. Smutná and A. Irra for the care with which they carried out various tasks.  相似文献   
965.
The paper gives the results of measuring the temperature dependence of the electrical conductivity(T), the Hall coefficientR H (T) and the magnetic susceptibility(T) forn-type CdSnAs2. The effective mass of the electrons was determined by analysis of the measured dependences on the basis of the simple theory for an isotropic non-degenerate semi-conductor. It was found to bem n /m 0=2×10–2 in the intrinsic region and does not depend on the temperature; the energy gap ise g 0=0·26 eV and the molar susceptibility of the CdSnAs2 lattice G mol=–112× ×10–6. The mobility of the electrons in the intrinsic region reaches a value of n =25 000 cm2V–1sec–1 at 500°K and decreases exponentially n T –1.67 with rising temperature. The density of CdSnAs2 was determined pyknometrically,g9=5·35 g cm–3. The measurements were made on ann-type polycrystalline sample consisting of crystals a few millimetres in diameter, which at a temperature of 100°K had a free electron concentration ofn s =6×1016 cm–3.
CdSnAs2
(T), R H (T) (T) CdSnAs2 . m n /m 0= =2.10–2, ; E G 0=0,26 eV, CdSnAs2 G mol= =–112.10–6. 500°K n =25 000 cm2V–1sec–1 , n T –1,67. CdSnAs2 =5,35 g cm–3. , , 100°K n s =6.1016cm–3.


The authors would like to thank Mr. P. Jansa for help in measuring the temperature dependence of the magnetic susceptibility.  相似文献   
966.
The plastic deformation of Fe-3%Si alloy single crystals made from the melt is studied by the method of etching of dislocations. At a room-temperature and at static stress deformation by slip occurs in the 1/2〈111〉 directions along planes of maximum resolved shear stress. The plastic properties are determined by the motion of screw dislocations which cause the broadening of slip bands.  相似文献   
967.
The characteristic function is introduced, describing completely the monochromating effect of monochromating units. Expressions for this function are presented for monochromating units frequently used. An example of computation for Johansson's unit shows the conditions in a special case. The curves indicating the shift of the wavelength centroid of monochromated radiation for crystals of different perfection allow conclusions to be drawn about the influence of the alignment of the crystal on precision measurements of lattice constants. The experiments verify the suggested model. The computations for a given experimental arrangement permit a simple determination of the effective breadth of the reflection curve, if a distance of two suitably chosen diffraction lines of a polycrystalline specimen is measured. Finally, it was found experimentally that a small elastic bending does not essentially alter the reflection curve of highly elastic and imperfect crystals unless macroscopic distortions are present.
, . . . , , . . , . , , , .


The author is deeply grateful to Prof. A. Kochanovská for her encouraging interest and wishes to express his thanks to Z. Hemanová for her careful computations.  相似文献   
968.
( )K- Fe, Ti Ca . , , , . , , , K- , .
The use of fluorescent X-rays for contact microradiography
The possibilities of using fluorescentK-radiation of the elements Fe, Ti and Ca for contact microradiography of thin, little absorbing samples were studied and a simple set-up for carrying out this method, which uses a common type of microstructural X-ray tube as a source of the exciting radiation, was proposed. The experiments performed showed that if large magnifications are not required secondary-excitedK-radiation of the above-mentioned elements can be advantageously used for contact microradiography without the exposure times becoming impracticably long.
  相似文献   
969.
970.
It was studied the tin phase composition of the electrodeposited alloys produced at different temperatures and current densities from an acid chloride/fluoride electrolyte and an acid chloride bath. Mössbauer spectra were consistent with a Ni3Sn4 intermetallic compound, dissolved tin, and a Cu?Sn intermetallic compound formed at the interface of the copper substrate.  相似文献   
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