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311.
We consider an n-player finite strategic game. The payoff vector of each player is a random vector whose distribution is not completely known. We assume that the distribution of a random payoff vector of each player belongs to a distributional uncertainty set. We define a distributionally robust chance-constrained game using worst-case chance constraint. We consider two types of distributional uncertainty sets. We show the existence of a mixed strategy Nash equilibrium of a distributionally robust chance-constrained game corresponding to both types of distributional uncertainty sets. For each case, we show a one-to-one correspondence between a Nash equilibrium of a game and a global maximum of a certain mathematical program.  相似文献   
312.
The present paper reports the thermoluminescence (TL) glow curve of Eu2+-activated SrAl2O4 phosphor with different UV exposure times. Evaluation of kinetic parameters was done by the peak shape method. The recorded glow curve shifts towards lower temperatures with respect to increasing UV exposure time. The peaks were found at 146.76, 141.34 and 140.37 °C, respectively, for 5, 10 and 15 min of UV exposure using the heating rate of 3°C s?1. The glow peak shows the second-order kinetics. Different kinetic parameters, i.e. trap depth, order of kinetics, activation energy, and frequency factor are also calculated. The XRD pattern of the sample is compared with reported XRD using the software match.  相似文献   
313.
1-Naphthol 2-hydroxylase (1-NH) catalyzes the conversion of 1-naphthol to 1,2-dihydroxynaphthalene. 1-NH from carbaryl degrading Pseudomonas strain C5 was purified and characterized for its kinetic and spectroscopic properties. The enzyme was found to be NAD(P)H-dependent external flavin monooxygenase. Though the kinetic parameters of 1-NH from strain C5 appear to be similar to 1-NH enzyme from strains C4 and C6, however, they differ in their N-terminal sequences, mole content of flavin adenine dinucleotide (FAD), reconstitution of apoenzyme, and K i. 1-NH showed narrow substrate specificity with comparable hydroxylation efficiency on 1-naphthol and 5-amino 1-naphthol (~30 %) followed by 4-chloro 1-naphthol (~9 %). Salicylate was found to be the nonsubstrate effector. The flavin fluorescence of 1-NH was found to increase in the presence of 1-naphthol (K d?=?11.3 μM) and salicylate (K d?=?1027 μM). The circular dichroism (CD) spectra showed significant perturbations in the presence of NAD(P)H, whereas no changes were observed in the presence of 1-naphthol. Naphthalene, 1-chloronaphthalene, 2-napthol, and 2-naphthoic acid were found to be the mixed inhibitors. Chemical modification studies showed the probable involvement of His, Cys, and Tyr in the binding of 1-naphthol, whereas Trp was found to be involved in the binding of NAD(P)H.  相似文献   
314.
Transport of contaminants through clays is characterized by a very low dispersivity, but depends on the sensitivity of its intrinsic permeability to the contaminant's concentration. An additional constitutive relationship for a variable intrinsic permeability is thus adopted leading to a coupled system of equations for diffusive–advective transport in multicomponent liquid. A one-dimensional transport problem is solved using finite difference and Newton–Raphson procedure for nonlinear algebraic equations. The results indicate that although diffusion contributes to an increase of transport with respect to pure advection, the flux ultimately depends on end boundary conditions for concentration which, if low, may actually slow down the evolution of concentration and thus of permeability. Indeed, the advective component of flux may still remain secondary if the end portion of the layer remains unaffected by high concentrations. With no constraints on concentration at the bottom (zero concentration gradient boundary condition) and high concentration applied at the top, a significant shortening of the breakthrough time occurs.  相似文献   
315.
Novel substituted phenol-based new symmetrical bis(2-hydroxy-3-isopropyl-6-methyl-benzaldehyde)ethylenediamine (1) has been designed and synthesized. The compound 1 fluorometrically recognized Cu2+ ion in CH3OH/H2O (90:10, v/v) by exhibiting an increase in emission upon complexation. In addition, Cu2+ gave rise to a change in colour of the solution of compound 1, which was clearly visible to the naked eye under UV irradiation. The association constant (K) of compound 1 with Cu2+ ion was computed with the Benesi-Hildebrand plot and Scatchard plot at 43,000 M?1 and 43,011 M?1 respectively.  相似文献   
316.
Vikas Mittal 《哲学杂志》2013,93(7):777-793
Montmorillonite layered silicate has been commonly used to reinforce polymer matrices. Due to its swelling in water, organic modification of the mineral surface is easily achieved which makes the surface compatible with polymers. Other minerals like mica and vermiculite though can also lead to high aspect ratio platelets in nanocomposites, but they do not swell in water owing to much stronger electrostatic forces of attraction holding their platelets together (layer charge density >0.5?eq?·?mol?1 in comparison with 0.25–0.5?eq?·?mol?1 for montmorillonite). In current study, milling, delamination and cation exchange processing of mica and vermiculite minerals has been reported to explore their potential as reinforcement materials. Wet grinding and subsequent sieving of the coarse minerals led to fine-sized particles suitable to perform chemical delamination in water. The delamination process resulted in Li-mica and Na-vermiculite with enhanced access to the interlayer cations, thus, higher CEC. Successful surface modification of the delaminated minerals with alkyl ammonium ions could be achieved which resulted in significant enhancements in their basal plane spacing. Peak degradation temperatures of 260°C were measured for C18 and 2C18 modified vermiculite, whereas 300°C and 275°C were observed respectively for C18 and 2C18 modified mica minerals which make them suitable for compounding with polymers at high temperature.  相似文献   
317.
We compared the effectiveness of different forcefields for computing the density of CHNO explosives using crystal packing methodology. Densities obtained for 68 CHNO explosives of various sizes vary in chemical nature, contain different functionalities, and are compared with the experimental data. The predicted densities with Dreiding forcefield for 84% explosives without an aromatic ring in the structure (NonAr-Explosives) gave deviation within 5%. While the predicted densities with PCFF forcefield for 83% of explosives containing aromatic ring in the structure (Ar-Explosives) found within 4% deviation, the computed densities using various forcefields judged with experimental data indicate that choice of forcefield is crucial for precise density prediction. This study will be valuable in selecting forcefield for crystal packing calculations and directing research efforts towards the design of denser CHNO energetic materials. Please be informed that Graphical Abstract is not allowed per journal style. Thus, the graphical abstract provided was not captured.Author agrees with the comment.  相似文献   
318.
319.
Photoluminescence studies of pure and Dy3+, Eu3+ doped Sr2CeO4 compounds are presented by oxalate precipitation method for solid state lighting. The prepared samples also characterized by XRD, SEM (EDS) and FTIR spectroscopy. The pure Sr2CeO4 compound displays a broad band in its emission spectrum when excited with 280 nm wavelength, which peaks centered at 488 nm, which is due to the energy transfer between the molecular orbital of the ligand and charge transfer state of the Ce4+ ions. Emission spectra of Sr2CeO4 with different concentration of Dy3+ ions under near UV radiation excitation, shows that intensity of luminescence spectra is found to be affected by Dy3+ ions, and it increases with adding some percentages of Dy3+ ions. The maximum doping concentration for quenching is found to be Dy3+?=?0.2 mol % to Sr2+ions. The observed broad spectrum from 400 to 560 nm is mainly due to CT transitions in Sr2CeO4 matrix and some fractional contribution of transitions between 4F9/26H15/2 of Dy3+ ions. Secondly the effect of Eu3+ doping at the Sr2+ site in Sr2CeO4, have been studied. The results obtained by doping Eu3+ concentrations (0.2 mol% to 1.5 mol%), the observed excitation and emission spectra reveal excellent energy transfer between Ce4+ and Eu3+. The phenomena of concentration quenching are explained on the basis of electron phonon coupling and multipolar interaction. This energy transfer generates white light with a color tuning from blue to red, the tuning being dependent on the Eu3+ concentration. The results establish that the compound Sr2CeO4 with Eu3+?=?1 mol% is an efficient “single host lattice” for the generation of white lights under near UV-LED and blue LED irradiation. The commission internationale de I’Eclairage (CIE) coordinates were calculated by Spectrophotometric method using the spectral energy distribution of prepared phosphors.  相似文献   
320.
We describe a rationally designed peptide with tunable surface activity, where the dynamics of surface activity are an outcome of helical folding. Our rationally designed model peptide is surface-active only as an alpha-helix. We apply circular dichroism to show that the folded population can be controlled with changes in electrolyte concentration, and we apply pendant bubble tensiometry to explore dynamic surfactant activity. This study shows a peptide that responds to environmental stimuli with dynamic folding and surface activity. Extending this concept to selective binding peptides will lead to new tools, where dynamic surface activity is coupled to targeted binding.  相似文献   
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