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111.
0.5BiNd x Fe1?x O 3 ? 0.5PbTiO3 (BN x F1?x ? PT)(x = 0.05, 0.10, 0.15, 0.20) composites were successfully synthesized by a solid state reaction technique. At room temperature, X-ray diffraction shows tetragonal structure for all concentrations of Nd doped 0.5BiFeO3 ? 0.5PbTiO3 composites. The nature of Nyquist plot confirms the presence of bulk effects only for BN x F1?x ? PT (x = 0.05, 0.10, 0.15, 0.20) composites. The bulk resistance is found to decreases with the increasing temperature as well as Nd concentration and exhibits a typical negative temperature coefficient of resistance (NTCR) behavior. Both the complex impedance and modulus studies have suggested the presence of non-Debye type of relaxation in the composites. Conductivity spectra reveal the presence of hopping mechanism in the electrical transport process of the composites. The activation energy calculated from impedance plot of the composite decreases with increasing Nd x concentration and found to be 0.89, 0.76, 0.71 and 0.70 eV for x=0.05, 0.10, 0.15 and 0.20 respectively.  相似文献   
112.
International Journal of Theoretical Physics - Quantum algorithm, as compared to classical algorithm, plays a notable role in solving linear systems of equations with an exponential speedup. Here,...  相似文献   
113.
Dyes are commonly used in coloring clothes; in fertilizers, as anti-freezers, as detergents and so on. The use of such dyes has carcinogenic and genotoxic effects. These dyes require proper removal from the environment. Subsequently, a green and low-cost approach promises to adhere to sustainability of the environment while maximum removal of these toxic dyes. The present study describes removal of methyl violet (MV) dye by adsorption process magnetically separable Fe3O4-coir pith composites. The study was evaluated in batch system taking the optimum conditions as: pH: 7, contact time: 12 h, stirring speed: 200 rpm, concentration of dye: 100 mg/L, adsorbent weight: 3 g/L, temp.: 308 K. The central composite design approach of response surface methodology in design-expert software showed maximum removal efficiency (>98%) for optimal parameters. The experimental equilibrium data fitted reasonably well to Langmuir isotherm model. ANOVA analysis along with Fisher's statistical test was also performed to validate the model. The predicted model was at par with the experimental values with adjusted R2 of 0.9914. A thorough investigation of kinetic (RPseudo second order2 = 0.99; RPseudo second order2=0.97;Rintra?particle diffusion2=0.98), thermodynamic, adsorption isotherm (RLangmuir isotherm2=0.997 RFreundlich isotherm2=0.99 and eco-toxicological characteristics were performed for proper evaluations of the properties as well as sustainability of the adsorbent material. The whole research indicated encouraging potential of the developed material for adsorption, reusability and sustainability in applications for industrial scale wastewater treatment.  相似文献   
114.
Protein pores that selectively transport ions across membranes are among nature’s most efficient machines. The selectivity of these pores can be exploited for ion sensing and water purification. Since it is difficult to reconstitute membrane proteins in their active form for practical applications it is desirable to develop robust synthetic compounds that selectively transport ions across cell membranes. One can envision tuning the selectivity of pores by incorporating functional groups inside the pore. Readily accessible octapeptides containing (aminomethyl)benzoic acid and alanine are reported here that preferentially transport cations over halides across the lipid bilayer. Ion transport is hypothesized through pores formed by stable assemblies of the peptides. The aromatic ring(s) appear to be proximal to the pore and could be potentially utilized for functionalizing the pore interior.  相似文献   
115.
Regio- and stereoselective cycloaddition of β-nitroacrylates with electron deficient cyclohexa-2,4-dienones leading to highly functionalised bicyclo[2.2.2]octanes having the β-nitroester group and their transformation to bicyclo[2.2.2]octanes having β-aminoester functionality is described.  相似文献   
116.
Journal of Radioanalytical and Nuclear Chemistry - Elemental concentrations namely P, S, Cl, K, Ca, Sc, Ti, Mn, Fe, Cu, Zn, Rb, Br and Sr were determined using Particle Induced X-ray Emission...  相似文献   
117.
We present ab initio calculations which show that the direct-band-gap, effective masses and Fermi velocities of charge carriers in ZnO monolayer (ML-ZnO) in graphene-like honeycomb structure are all tunable by application of in-plane homogeneous biaxial strain. Within our simulated strain limit of ±10%±10%, the band gap remains direct and shows a strong non-linear variation with strain. Moreover, the average Fermi velocity of electrons in unstrained ML-ZnO is of the same order of magnitude as that in graphene. The results promise potential applications of ML-ZnO in mechatronics/straintronics and other nano-devices such as the nano-electromechanical systems (NEMS) and nano-optomechanical systems (NOMS).  相似文献   
118.
1,8-Diazacubane-templated nickel(II) sulfate with the Kagome structure prepared under solvothermal conditions exhibits interesting magnetic properties.  相似文献   
119.
Lithium-doped zinc oxide films were synthesized by spray pyrolysis technique, and their structural and optical properties were characterized by X-ray diffraction, transmission electron microscope, atomic force microscope, and photoluminescence spectroscopy. The effect of doping on the photoluminescence properties was investigated at room temperature (300 K). Polycrystalline nature of the films was confirmed from X-ray diffraction and electron microscopic studies. A two-dimensional fringe moiré pattern with spacing of 1.2 nm was observed for the doped thin film. Lithium doping has been found to increase the roughness of the surface, thus making the film more passivated. Lithium was found to play a key role in the excitonic as well as visible luminescence of ZnO.  相似文献   
120.
We present here a theoretical study of the effect of Jahn-Teller(J-T) distortion on the self-energy of electrons in the CMR manganites. The model consists of the itinerant e g electrons distorted by J-T effect and the localized t 2g core electrons carrying strong ferromagnetism due to Hund’s rule. The phonon interacts with the e g electrons as well as the J-T distorted e g band. The electron Green’s functions are calculated by Zubarev’s technique. The electron self-energy which carries all the information of the model is calculated from the Green’s function. The effect of J-T distortion, magnetism on the frequency and temperature dependent dynamic self-energy is presented in this paper. The results are discussed.  相似文献   
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