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911.
采用多模熔石英光纤对磷酸铕玻璃和铒的磷酸盐烧结体样品进行了光纤传输拉曼光谱测量,并与直接测量样品的拉曼光谱进行对比,两者的结果基本符合,从而证实了光纤传输拉曼光谱对样品检测的可行性,达到扩展拉曼光谱仪的应用领域,为特定条件下研究材料性能提供了良好的途径。由此还可发现和研制出新的光电产品材料。 相似文献
912.
S. K. Andrukhovich A. V. Berestov B. A. Martsynkevich A. M. Khil'manovich N. Antovich 《Journal of Applied Spectroscopy》1998,65(2):290-296
In the paper we describe the capabilities of the multidimensional (multidetector) spectroscopy of photon cascades. Attention
is paid to a considerable increase in the resolution of multidetector spectrometers compared to one-detector spectrometers.
We give a derivation of the radiation intensity detection limit, which relates all the basic characteristics of a multidetector
spectrometer, and present examples of calculation of spectrometer characteristics.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 2, pp. 278–283, March–April, 1998. 相似文献
913.
The measurement in thermal equilibrium of the vacancy contribution to the residual resistivity of metals has posed certain
difficulties. The recent experiment of Celasco and co-workers represents a new, powerful approach to this problem, via the
measurement of the power spectrum of the voltage noise generated by resistivity fluctuations. The latter originate in vacancy
number fluctuations. We develop a theory for the power spectrum, incorporating three basic features. Vacancies can be annihilated
in the material and they diffuse. Grain boundaries act as sources and sinks for vacancies. Both annihilation (a form of reaction)
and diffusion are noisy processes. We therefore set up and solve a reactive-diffusive stochastic equation for the instantaneous
density, with appropriatefinite boundary conditions. Assuming for simplicity that the grains are spherical, the power spectrum is evaluated exactly, in closed
form. A detailed comparison with experiment is made. The physical origins of different time scales in the problem and the
consequent frequency regimes in the power spectrum are analysed. Recognising the very general applicability of our theory,
we also mention possible applications to other problems. 相似文献
914.
An emulsion chamber was used to study the characteristics of high energy nuclear interactions from the production spectra
ofγ-rays. The emulsion chamber, which comprised of two parts, namely the detector and the graphite producer unit, was exposed
to cosmic rays for about 7 hr at an atmospheric depth of 10 g cm−2 at Hyderabad (geomagnetic latitude 7·6°N). 720 electromagnetic cascades due toγ-rays were recorded in the detector. These cascades were classified into three groups; (a)γ-rays from nuclear interactions in the detector (b)γ-rays from nuclear interactions in the producer unit and (c)γ-rays of atmospheric origin. The energies of the cascades were determined using photometric method. The spectra ofγ-rays from groups (a) and (c) were determined and compared with similar spectra obtained at greater atmospheric depths. The
spectra were found to obey a power law. The spectrum ofγ-rays of atmospheric origin was found to steepen at high energies,E
r>2200 GeV. 相似文献
915.
916.
The laser Raman spectrum of tere-phthalaldehyde powder has been recorded on a Jobin Yvonhg 2S spectrophotometer with a~100 mW Argon-Ion laser. The infrared spectrum of the solid substance has been recorded on a Perkin-Elmer
621 spectrophotometer in the region 300–4000 cm-1 using KBr and nujol mull techniques. The observed frequencies have been assigned in terms of the fundamentals, overtones
and combinations assumingD
2h point-group symmetry. 相似文献
917.
An empirical mass formula is tested for the basic fermion sequences of charged quarks and leptons. This relation is a generalization
of Barut’s mass formula for the lepton sequence (e, μ, τ......). It is found that successful mass extrapolation to the third and possibly to other higher generations (N>2) can be obtained with the first and second generation masses as inputs, which predicts the top quark massm
t to be around 20 GeV. This also leads to the mass ratios between members of two different sequences (i) and (i′) corresponding to the same higher generations (N>2). 相似文献
918.
G.?N.?TenEmail author T.?G.?Burova V.?I.?Baranov 《Journal of Applied Spectroscopy》2005,72(1):104-110
Calculations of the frequencies and absolute intensities of the IR bands of plane vibrations of thymine and N1,N3-deuterothymine in various phase states have been carried out. It has been shown that in the polycrystalline state thymine forms hydrogen bonds C2=O8...HN1 and C2=O8...HN3, and in an aqueous solution the intermolecular interaction is realized by means of the hydrogen bonds O8...HO and O...HN1.__________Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 1, pp. 99–105, January–February, 2005. 相似文献
919.
Yu.?Yu.?BacherikovEmail author N.?V.?Kitsyuk S.?V.?Optasyuk V.?E.?Rodionov A.?A.?Stadnik E.?G.?Reutova 《Journal of Applied Spectroscopy》2005,72(1):95-98
The influence of atmospheric passivation on the electro- and photoluminescent properties of ZnS powders doped with In and/or CuCl is investigated. The processes proceeding in the material during thermal doping with In and/or CuCl as well as participation of oxygen in forming the electro- and photoluminescent radiation centers are discussed. The possibility of creating electro- and photoluminophors based on ZnS that have a continuous spectrum in the visible range with the same spectral density is shown. An electroluminophor based on ZnS:In,Cu,Cl that emits radiation with practically the same spectral density in the 550–750-nm range has been created as well as a photoluminophor based on ZnS:In that emits similarly within the range 500 < < 700 nm.__________Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 1, pp. 90–93, January–February, 2005. 相似文献
920.
T.?A.?Prokof’evEmail author B.?A.?Polezhaev A.?V.?Kovalenko 《Journal of Applied Spectroscopy》2005,72(6):865-871
The mechanisms of photoluminescence excitation of Mn2+ ions in ZnS crystals have been investigated on the basis of complex analysis of the temperature dependences of the photoluminescence
and photoluminescence-excitation spectra of ZnS:Mn crystals. The activation energy of a manganese luminescence center was
estimated at Ea = 0.17 ± 0.05 eV. It is shown that Ea represents an energy band with a width ΔEa = 0.1 eV, within which a manganese luminescence center can experience radiationless recombination.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 6, pp. 788–793, November–December, 2005. 相似文献