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11.
    
The aim of this work was to deeply investigate the structure and properties of electrochemically synthesized silver nanoparticles (AgNPs) through high-resolution techniques such as transmission electron microscopy (TEM), scanning electron microscopy (SEM), Zeta Potential measurements, and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). Strong brightness, tendency to generate nanoclusters containing an odd number of atoms, and absence of the free silver ions in solution were observed. The research also highlighted that the chemical and physical properties of the AgNPs seemed to be related to their peculiar oxidative state as suggested by X-ray photoelectron spectroscopy (XPS) and X-ray powder diffraction (XRPD) analyses. Finally, the MTT assay tested the low cytotoxicity of the investigated AgNPs.  相似文献   
12.
New non-ionic microemulsions consisting of pentaethyleneglycol dodecyl ether, water, and 1-chloroalkanes were prepared, and their phase behavior was studied. A homologous series of five different 1-chloroalkanes from 1-chlorooctane to 1-chlorohexadecane was studied. The phase behavior of the microemulsions was determined by vertical sections through the Gibbs' phase prism ("fish" plots), from which valuable information such as the microemulsion balance temperature (T(0)), efficiency of the surfactant (phi*), temperature extension of the three-body phase (DeltaT), mean temperature (T(m)), and the monomeric solubility in oil (phi(mon,oil)) was obtained. The chlorinated alkanes in the microemulsions shift the balance temperature to about 14 degrees C lower compared with their n-alkane counterparts. This indicates the polar nature of the chlorinated oils and their ability to penetrate the surfactant film. The chlorinated alkanes thus behave as short n-alkane molecules and lower the spontaneous curvature of the microemulsion droplets. The efficiency of the surfactant and the monomeric solubility in oil systematically depend on the alkyl chain length of the oil, with the efficiency and solubility decreasing with increasing alkyl chain length of 1-chloroalkane. The size and shape of the microemulsion droplets in the microemulsion phase were studied by small-angle X-ray scattering (SAXS). For a surfactant-to-oil volume fraction ratio of 0.80, the droplets can be described by ellipsoidal shapes, and the size of the droplets increased with increasing alkyl chain length.  相似文献   
13.
Half-Heusler compounds are an impressive class of materials with a huge potential for different applications such as in future energy, especially in the fields of thermoelectrics and solar cells. We present ab fnitio total energy calculations within the modified Becke-Johnson generalized gradient approximation (mBJ-GGA) to obtain the physical properties of SrAlGa compounds. The structural, elastic, acoustic, electronic, chemical bonding, optical, and thermoelectric properties are calculated and compared with the available calculation data. The SrAlGa is found to be a small-band-gap (0.125-0.175 eV) material, suitable for thermoelectric applications with a relatively high Seebeck coefficient. Also, SrAIGa has the potential in the optoelectronic applications due to high optical conductivity and reflectivity in the infrared and visible region of electromagnetic spectra.  相似文献   
14.
In this work, the intense deuteron beam from a plasma focus device is investigated by the activation yield-ratio technique. It is shown that boron-carbide (B4C) and boron-nitride (BN) are complimentary targets for high energy deuteron beam studies. For deuteron spectra of the form dNd/dEEn, when deuteron spectra decrease relatively gradually (n<6) BN is a better choice, while for the case of very rapidly decreasing deuteron spectra (n>6), B4C is more suitable.  相似文献   
15.
S. Roshan Entezar   《Physics letters. A》2009,373(38):3413-3418
The entanglement of a two-level atom and its radiation field near the edge of a photonic band gap is studied by using the quantum entropy. Unlike the free space case, there is a steady-state entanglement between the atom and its spontaneous emission field even when the atomic transition frequency lies outside the band gap. Moreover, the degree of entanglement, which is due to the formation of atom–photon bound dressed state, depends on the detuning of the atomic transition frequency from the photonic band edge and can be controlled by a controllable photonic band gap crystal.  相似文献   
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The generalized equal width (GEW) equation is solved numerically by the Petrov-Galerkin method using a linear hat function as the test function and a quadratic B-spline function as the trial function. Product approximation has been used in this method. A linear stability analysis of the scheme shows it to be conditionally stable. Test problems including the single soliton and the interaction of solitons are used to validate the suggested method, which is found to be accurate and efficient. Finally, the Maxwellian initial condition pulse is studied.  相似文献   
18.
The equal width equation is solved numerically by Petrov-Galerkin method using linear hat function and quadratic B-spline function as trial and test functions respectively. Product approximation has been used in this method. A linear stability analysis of the scheme is shown to be conditionally stable. Test problems including the single soliton and the interaction of solitons are used to validate the suggested method, which is found to be accurate and efficient. The Maxwellian initial condition pulse and the development of an undular bore are also studied.  相似文献   
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The existence of the surface polaritons at the interface separating a semi-infinite uniform left-handed metamaterial and a one-dimensional photonic crystal composed of alternating layers of two kinds of single-negative materials is theoretically investigated. The dispersion characteristics of the surface polaritons are analyzed and demonstrated that in the presence of metamaterial, the surface polaritons are sensitive to light polarization, so that there exist only backward TM-polarized (or TE-polarized) kind of the surface polaritons depending on the ratio of the thicknesses of the two periodic stacking layers. The existence regions of the surface polariton modes are determined for both TM-polarized and TE-polarized surface polariton modes.  相似文献   
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