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81.
82.
Jürgen Mimkes 《Physica A》2010,389(8):1665-1676
Economic growth depends on capital and labor and two-dimensional calculus has been applied to economic theory. This leads to Riemann and Stokes integrals and to the first and second laws of production and growth. The mathematical structure is the same as in thermodynamics, economic properties may be related to physical terms: capital to energy, production to physical work, GDP per capita to temperature, production function to entropy. This is called econophysics. Production, trade and banking may be compared to motors, heat pumps or refrigerators. The Carnot process of the first law creates two levels in each system: cold and hot in physics; buyer and seller, investor and saver, rich and poor in economics. The efficiency rises with the income difference of rich and poor. The results of econophysics are compared to neoclassical theory. 相似文献
83.
Marina Davydova Alexander Kromka Oleg Babchenko Karel Hruska 《Applied Surface Science》2010,256(18):5602-1312
Diamond nanorods were fabricated for a sensing device by utilizing reactive ion etching in CF4/O2 radio frequency plasma. The length of the nanorods has been controlled by the ion etching time. The obtained morphologies were investigated by scanning electron microscopy. The gas sensing properties of the H-terminated diamond-based sensor structures are indicating that we have achieved high sensitivity to detect phosgene gas. Also, our sensor exhibited good selectivity between humid air and phosgene gas if the measurement is conducted at elevated temperatures, such as 140 °C. Furthermore, such sensor response rating could reach as high value as 4344 for the phosgene gas, which was evaluated for the sample consisting of the longest nanorods (up to 200 nm). 相似文献
84.
Edward Sun 《Applied Surface Science》2010,256(16):5021-5223
Temperature-dependent photoluminescence (PL) from Si nanodots with Al2O3 surface passivation layers was studied. The Si nanodots were grown by low pressure chemical vapor deposition and the Al2O3 thin films were prepared by atomic layer deposition (ALD), respectively. The BOE (Buffer-Oxide-Etch) treatment resulted in the damaged surface of Si nanodots and thus caused dramatic reduction in the PL intensity. Significant enhancement of the PL intensity from Si nanodots after the deposition of Al2O3 thin films was observed over a wide temperature range, indicating the remarkable surface passivation effect to suppress the non-radiative recombination at the surface of Si nanodots. The results demonstrated that the Al2O3 surface passivation layers grown by ALD are effectually applicable to nanostructured silicon devices. 相似文献
85.
Yttrium oxide thin films are deposited by microwave electron cyclotron resonance (ECR) plasma assisted metal organic chemical vapour deposition process using an indegeneously developed Y(thd)3 {(2,2,6,6-tetramethyl-3,5-heptanedionate)yttrium} precursor. Depositions were carried out at two different argon gas flow rates keeping precursor and oxygen gas flow rate constant. The deposited coatings are characterized by X-ray photoelectron spectroscopy (XPS), glancing angle X-ray diffraction (GIXRD) and infrared spectroscopy. Optical properties of the films are studied by spectroscopic ellipsometry. Hardness and elastic modulus of the films are measured by load depth sensing nanoindentation technique. Stability of the film and its adhesion with the substrate is inferred from the nanoscratch test.It is shown here that, the change in the argon gas flow rates changes the ionization of the gas in the microwave ECR plasma and imposes a drastic change in the characteristics like composition, structure as well as mechanical properties of the deposited film. 相似文献
86.
M. Gligor M. Ausloos 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,63(4):533-539
GDP/capita correlations are investigated in various time windows (TW), for the time interval 1990–2005. The target group of
countries is the set of 25 EU members, 15 till 2004 plus the 10 countries which joined EU later on. The TW-means of the statistical
correlation coefficients are taken as the weights (links) of a fully connected network having the countries as nodes. Thereafter
we define and introduce the overlapping index of weighted network nodes. A cluster structure of EU countries is derived from the statistically relevant eigenvalues and
eigenvectors of the adjacency matrix. This may be considered to yield some information about the structure, stability and
evolution of the EU country clusters in a macroeconomic sense. 相似文献
87.
Y. Safa D. Pfenniger 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,66(3):337-352
The equation of state and the stability of the helium-molecular hydrogen mixture at cryogenic temperature up to moderate pressure
are studied by means of current molecular physics methods and statistical mechanics perturbation theory. The phase separation,
segregation and hetero-coordination are investigated by calculating the Gibbs energy depending on the mixture composition,
pressure and temperature. Low temperature quantum effects are incorporated via cumulant approximations of the Wigner-Kirkwood
expansion. The interaction between He and H2 is determined by Double Yukawa potentials. The equation of state is derived from the hard sphere system by using the scaled
particle theory. The behavior of the mixture over a wide range of pressure is explored with the excess Gibbs energy of mixing
and the concentration fluctuations in the long wavelength limit. The theory is compared to cryogenic data and Monte-Carlo
calculation predictions. Contrary to previous similar works, the present theory retrieves the main features of the mixture
below 50 K, such as the critical point and the condensation-freezing curve, and is found to be usable well below 50 K. However,
the method does not distinguish the liquid from the solid phase. The binary mixture is found to be unstable against species
separation at low temperature and low pressure corresponding to very cold interstellar medium conditions, essentially because
H2 alone condenses at very low pressure and temperature, contrary to helium. 相似文献
88.
Basu A Joanny JF Jülicher F Prost J 《The European physical journal. E, Soft matter》2008,27(2):149-160
We discuss general features of noise and fluctuations in active polar gels close to and away from equilibrium. We use the
single-component hydrodynamic theory of active polar gels built by Kruse and coworkers to describe the cytoskeleton in cells.
Close to equilibrium, we calculate the response function of the gel to external fields and introduce Langevin forces in the
constitutive equations with correlation functions respecting the fluctuation-dissipation theorem. We then discuss the breakage
of the fluctuation-dissipation theorem due to an external field such as the activity of the motors. Active gels away from
equilibrium are considered at the scaling level. As an example of application of the theory, we calculate the density correlation
function (the dynamic structure factor) of a compressible active polar gel and discuss possible instabilities. 相似文献
89.
E. Ben-Jacob 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,65(3):315-322
I describe how bacteria develop complex colonial patterns by utilizing intricate communication capabilities, such as quorum
sensing, chemotactic signaling and exchange of genetic information (plasmids) Bacteria do not store genetically all the information
required for generating the patterns for all possible environments. Instead, additional information is cooperatively generated
as required for the colonial organization to proceed. Each bacterium is, by itself, a biotic autonomous system with its own
internal cellular informatics capabilities (storage, processing and assessments of information). These afford the cell certain
plasticity to select its response to biochemical messages it receives, including self-alteration and broadcasting messages
to initiate alterations in other bacteria. Hence, new features can collectively emerge during self-organization from the intra-cellular
level to the whole colony. Collectively bacteria store information, perform decision make decisions (e.g. to sporulate) and
even learn from past experience (e.g. exposure to antibiotics)-features we begin to associate with bacterial social behavior
and even rudimentary intelligence. I also take Schrdinger’s’ “feeding on negative entropy” criteria further and propose that,
in addition organisms have to extract latent information embedded in the environment. By latent information we refer to the
non-arbitrary spatio-temporal patterns of regularities and variations that characterize the environmental dynamics. In other
words, bacteria must be able to sense the environment and perform internal information processing for thriving on latent information
embedded in the complexity of their environment. I then propose that by acting together, bacteria can perform this most elementary
cognitive function more efficiently as can be illustrated by their cooperative behavior. 相似文献
90.
Zyn VI 《The European physical journal. E, Soft matter》2008,25(1):51-59
A mathematical model of the volumetric part of plasma polymerization influenced by gravity is presented. Plasma-activated
adhesion of monomer molecules to a surface of a germinal particle is assumed as a basic mechanism of particulate growth. The
continuity equation for the flow of matter through the discharge has been formulated and solved in two extreme asymptotic
approximations --for small and major duration of the process. Several non-equilibrium distribution functions of the polymer
were obtained, for instance, an amount of the particles as a function of their size or time of fall. Within the adopted model
this function demonstrates a sharp downward increase inside a discharge. In addition it contains such parameters as the free
fall acceleration or reaction rate coefficients, variations of which enable control of the discharge and properties of the
disperse medium. 相似文献