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991.
The damage spreading of the Ising model on three kinds of networks is studied with Glauber dynamics. One of the networks is
generated by evolving the hexagonal lattice with the star-triangle transformation. Another kind of network is constructed
by connecting the midpoints of the edges of the topological hexagonal lattice. With the evolution of these structures, damage
spreading transition temperature increases and a general explanation for this phenomenon is presented from the view of the
network. The relationship between the transition temperature and the network measure-clustering coefficient is set up and
it is shown that the increase of damage spreading transition temperature is the result of more and more clustering of the
network. We construct the third kind of network-random graphs with Poisson degree distributions by changing the average degree
of the network. We show that the increase in the average degree is equivalent to the clustering of nodes and this leads to
the increase in damage spreading transition temperature.
相似文献
992.
A zero modes’ Fock space is constructed for the extended chiral WZNW model. It gives room to a realization of the fusion ring of representations of the restricted quantum universal enveloping
algebra at an even root of unity, and of its infinite dimensional extension by the Lusztig operators We provide a streamlined derivation of the characteristic equation for the Casimir invariant from the defining relations
of A central result is the characterization of the Grothendieck ring of both and in Theorem 3.1. The properties of the fusion ring in are related to the braiding properties of correlation functions of primary fields of the conformal current algebra model.
相似文献
993.
Nils M. Bezares-Roder Hemwati Nandan Heinz Dehnen 《International Journal of Theoretical Physics》2007,46(10):2429-2436
The exact static and spherically symmetric solutions of the vacuum field equations for a Higgs Scalar-Tensor theory (HSTT)
are derived in Schwarzschild coordinates. It is shown that in general there exists no Schwarzschild horizon and that the fields
are only singular (as naked singularity) at the center (i.e. for the case of a point-particle). However, the Schwarzschild
solution as in usual general relativity (GR) is obtained for the vanishing limit of Higgs field excitations. 相似文献
994.
Kalnina I Klimkane L Kirilova E Toma MM Kizane G Meirovics I 《Journal of fluorescence》2007,17(6):619-625
The fluorescent probe-aminoderivative of benzanthrone, ABM (developed at Riga Technical University, Riga, Latvia) was used
to characterize the membranes of lymphocytes of cancer patients: 46 patients with gastrointestinal diseases, 13 patients having
different primary localizations with massive metastases and intoxication. Patients were divided into three groups: (1) with
decreased fluorescence intensity, (2) normal fluorescence intensity, (3) increased fluorescence intensity. The lymphocytes
distribution among subsets differed between groups, in correspondence to the level of florescence intensity. Surgical treatment
affected the main immunological parameters and elevated the functional activity of lymphocytes. In the advanced tumors group,
fluorescence intensity correlates with the survival rate. Results suggest that determination of lymphocytes functional activity
by ABM can aid evaluation of the immune status in cancer patients. 相似文献
995.
Abhishek Verma Swati Nagpal Praveen K. Pandey P. K. Bhatnagar P. C. Mathur 《Journal of nanoparticle research》2007,9(6):1125-1131
Quantum Dots of CdS
x
Se1−x
embedded in borosilicate glass matrix have been grown using Double-Step annealing method. Optical characterization of the
quantum dots has been done through the combinative analysis of optical absorption and photoluminescence spectroscopy at room
temperature. Decreasing trend of photoluminescence intensity with aging has been observed and is attributed to trap elimination.
The changes in particle size, size distribution, number of quantum dots, volume fraction, trap related phenomenon and Gibbs
free energy of quantum dots, has been explained on the basis of the diffusion-controlled growth process, which continues with
passage of time. For a typical case, it was found that after 24 months of aging, the average radii increased from 3.05 to
3.12 nm with the increase in number of quantum dots by 190% and the size-dispersion decreased from 10.8% to 9.9%. For this
sample, the initial size range of the quantum dots was 2.85 to 3.18 nm. After that no significant change was found in these
parameters for the next 12 months. This shows that the system attains almost a stable nature after 24 months of aging. It
was also observed that the size-dispersion in quantum dots reduces with the increase in annealing duration, but at the cost
of quantum confinement effect. Therefore, a trade off optimization has to be done between the size-dispersion and the quantum
confinement. 相似文献
996.
A modified combustion process, namely a mixed fuel process making use of a mixture of two fuels, such as citric acid and glycine
has been developed to prepare nanocrystalline ceria powders. The effect of the mixed fuel and the different fuel to oxidant
ratios on the decomposition characteristics of the gels were investigated by simultaneous thermal analysis experiments. It
was established from various characterization techniques that the ceria powder prepared through the mixed fuel process has
got the optimum powder characteristics, namely, a surface area of 33.33 m2/g and a crystallite size of 14 nm compared to the powders produced through the combustion process using a single fuel like
glycine or citric acid. Such powders when sintered at 1250°C resulted in pellets with densities in the range of 94–96% of
theoretical density. In this paper, we have carried out systematic studies on the sintering of ceria powders prepared by different
approaches. The sintered ceramic from mixed fuel batch, exhibited and retained relative density more than 95% up to 1250°C
and this data clearly underscores the ability of this process in developing ceria ceramics with increased stability against
reduction. 相似文献
997.
998.
The value of intrinsic chlorophyll fluorescence polarization, and the intensity in emission spectrum were investigated in
leaf segments of Alocasia macrorrhiza under several stress conditions including different temperatures (25–50°C), various concentrations of NaCl (0–250 mM), methyl
viologen (MV, 0–25 μM), SDS (0–1.0%) and NaHSO3 (0–80 μM). Fluorescence emission spectrum of leaves at wavelength regions of 500–800 nm was monitored by excitation at 436 nm.
The value of fluorescence polarization (P value), as result of energy transfer and mutual orientation between chlorophyll molecules, was determined by excitation at
436 nm and emission at 685 nm. The results showed that elevated temperature and concentrations of salt (NaCl), photooxidant
(MV), surfactant (SDS) and simulated SO2 (NaHSO3) treatments all induced a reduction of fluorescence polarization to various degrees. However, alteration of the fluorescence
spectrum and emission intensity of F685 and F731 depended on the individual treatment. Increase in temperature and concentration of NaHSO3 enhanced fluorescence intensity mainly at F685, while an increase in MV concentration led to a decrease at both F685 and F731. On the contrary, NaCl and SDS did not cause remarkable change in fluorescence spectrum. Among different treatments, the
negative correlation between polarization and fluorescence intensity was found with NaHSO3 treatments only. We concluded that P value being measured with intrinsic chlorophyll fluorescence as probe in leaves is a susceptible indicator responding to
changes in environmental conditions. The alteration of P value and fluorescence intensity might not always be shown a functional relation pattern. The possible reasons of differed
response to various treatments were discussed. 相似文献
999.
A binary subwavelength structure for multilevel phase modulation can be designed by our previously proposed deterministic
design method without iterative optimization method. To use our design technique in various applications of a computer generated
hologram (CGH) like an array illuminator, beam-shaping, signal processing, and so on, an image quality of a reconstructed
image from a CGH has become much more important. In this paper, we verify the image quality of a reconstructed image from
a CGH designed by our method in terms of the modulation transfer function (MTF) and the spatial resolution. Simulation results
show that our technique can theoretically achieve a MTF of more than 99% over a wide range and a spatial resolution of less
than 9.66μm. 相似文献
1000.
The specific heat and related thermophysical properties of liquid Fe77.5Cu13Mo9.5 monotectic alloy were investigated by an electromagnetic levitation drop calorimeter over a wide temperature range from 1482 to 1818 K. A maximum undercooling of 221 K (0.13 Tm) was achieved and the specific heat was determined as 44.71 J·mol-1·K-1. The excess specific heat, enthalpy change, entropy change and Gibbs free energy difference of this alloy were calculated on the basis of experimental results. It was found that the calculated results by traditional estimating methods can only describe the solidification process under low undercooling conditions. Only the experimental results can reflect the reality under high undercooling conditions. Meanwhile, the thermal diffusivity, thermal conductivity, and sound speed were derived from the present experimental results. Furthermore, the solidified microstructural morphology was examined, which consists of (Fe) and (Cu) phases. The calculated interface energy was applied to exploring the correlation between competitive nucleation and solidification microstructure within monotectic alloy. 相似文献