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151.
The performance of dual chambered microbial fuel cell (MFC, Nafion 117, non-catalyzed graphite electrodes) in concurrence with anodic pH microenvironment was evaluated based on bioelectricity generation and wastewater treatment efficiency. Experiments were carried out at different anodic pH microenvironments (acidophilic (6), neutral (7) and alkaline (8)) using both aerated and ferricyanide catholytes with mixed consortia as anodic biocatalyst employing chemical wastewater. Acidophilic pH in anodic chamber showed effective performance with respect to power output compared to the corresponding neutral and alkaline operations. However, substrate degradation was observed to be higher at neutral condition followed by alkaline and acidophilic operations. Ferricyanide as catholyte showed positive influence on the power output parameters compared to aerated catholyte. Nature of the catholyte did not show any visible influence on the wastewater treatment efficiency.  相似文献   
152.
We study the nonlinear propagation of dust-ion acoustic (DIA) shock waves in an un-magnetized dusty plasma which consists of electrons, both positive and negative ions and negatively charged immobile dust grains. Starting from a set of hydrodynamic equations with the ion thermal pressures and ion kinematic viscosities included, and using a standard reductive perturbation method, the Kadomtsev-Petviashivili-Burgers (K-P-Burgers) equation is derived, which governs the evolution of DIA shocks. A stationary solution of the K-P-Burgers equation is obtained and its properties are analysed with different plasma number densities, ion temperatures and masses. It is shown that a transition from shocks with negative potential to positive one occurs depending on the negative ion concentration in the plasma and the obliqueness of propagation of DIA waves.  相似文献   
153.
Dual level of quantum mechanical calculations have been carried out for hydrogen abstraction from Piperazine [HN(CH2CH2)2NH] initiated by OH radical. Geometry optimisation and frequency calculations of all species involved in the titled reaction have been performed at M06-2X/6-31+G(d,p) level of theory. For the accuracy in the thermochemistry and kinetics data, single-point energy calculations have been further carried out at coupled cluster CCSD(T) method along with 6-311G(d,p) basis set. An energy profile diagram for the reaction has been plotted along with pre-reactive and post-reactive complexes at entrance and exit channels. Intrinsic reaction coordinates (IRCs) calculations have been performed for identification of real transition states that connect it via reactant to product. Our result shows that the H-atom abstraction takes place from the C–H position of Piperazine. The rate constant is calculated using canonical transition state theory (CTST) is found to be 2.86 × 10?10 cm3 molecule?1 s?1 which is in good agreement with the reported experimental rate constant (2.38 ± 0.28) × 10?10 cm3 molecule?1 s?1 at 298 K. We have also reported rate constant for the temperature range 300–500 K. Using group-balance isodesmic reaction, the standard enthalpies of formation for Piperazine and product radicals generated by hydrogen abstraction are reported. The branching ratios for both reaction channel (i.e. H-abstraction from –CH2 and –NH position of Piperazine) are found to be 93% and 7%, respectively. The calculated atmospheric life time of Piperazine is found to be 0.97 hour.  相似文献   
154.
We present an analysis of the xF3(x,Q2) structure function and Gross-Llewellyn Smith(GLS) sum rule taking into account the nuclear effects and higher twist correction. This analysis is based on the results presented in[N.M. Nath, et al., Indian J. Phys. 90 (2016) 117]. The corrections due to nuclear effects predicted in several earlier analysis are incorporated to our results of xF3(x,Q2) structure function and GLS sum rule for free nucleon, corrected upto next-next-to-leading order (NNLO) perturbative order and calculate the nuclear structure function as well as sum rule for nuclei. In addition, by means of a simple model we have extracted the higher twist contributions to the non-singlet structure function xF3(x,Q2) and GLS sum rule in NNLO perturbative orders and then incorporated them to our results. Our NNLO results along with nuclear effect and higher twist corrections are observed to be compatible with corresponding experimental data and other phenomenological analysis.  相似文献   
155.
An extraordinary amount of electrophysiological data has been collected from various brain nuclei to help us understand how neural activity in one region influences another region. In this paper, we exploit the point process modeling (PPM) framework and describe a method for constructing aggregate input-output (IO) stochastic models that predict spiking activity of a population of neurons in the "output" region as a function of the spiking activity of a population of neurons in the "input" region. We first build PPMs of each output neuron as a function of all input neurons, and then cluster the output neurons using the model parameters. Output neurons that lie within the same cluster have the same functional dependence on the input neurons. We first applied our method to simulated data, and successfully uncovered the predetermined relationship between the two regions. We then applied our method to experimental data to understand the input-output relationship between motor cortical neurons and 1) somatosensory and 2) premotor cortical neurons during a behavioral task. Our aggregate IO models highlighted interesting physiological dependences including relative effects of inhibition/excitation from input neurons and extrinsic factors on output neurons.  相似文献   
156.
We compute the longitudinal structure function F L of proton from its QCD (Quantum Chromodynamics) evolution equation in next-to-next-to-leading order (NNLO) approximation at small-x. Here we use Taylor series expansion method to solve the evolution equation for small-x and the obtained simple analytical expressions for F L provide t- and x-evolution equations for the computation of the longitudinal structure function. Finally, we compare our results with the recent H1, ZEUS experimental data and results of MSTW, CT10 parameterizations and Block, Donnachie-Landshoff (DL) models. Our results are in good agreement with the data and the related fittings and parameterizations, which can also be described within the framework of perturbative QCD.  相似文献   
157.
A Wireless Sensor Networks (WSNs) consist of spatially distributed autonomous sensors to cooperatively monitor physical or environmental conditions, such as temperature, sound, vibration, pressure, motion or pollutants. WSNs are more vulnerable to attacks and failures due to the involvement of many numbers of tiny sensor nodes. As the technology is tremendously increasing in the recent past, the implementation of this for various time critical applications is quite interesting and challenging. Moreover, WSNs have no specific hierarchical structures, leads to security and maintenance problems. Trust in WSN is defined as the degree of belief or confidence about the nodes based on the past interactions and observations has which become a mandatory requirement for reliable communication in WSN under security constraints. In this paper, we propose a Heuristic Approach based Trust Worthy Architecture for WSN that considers the challenges of the system and focus on the collaborative mechanism for trust evaluation and maintenance. Our proposed Architecture could also be capable of fulfilling critical security, reliability, mobility and performance requirements for reliable communication while being readily adaptable to different applications. The simulation results of the proposed architecture outperformed the recent trust worthy architecture using the analysis of the performance requirements such as communication overhead, memory requirements and energy consumption.  相似文献   
158.
Three copper(II) complexes, 1, 2, and 3 with L(1), L(2) and L(3) [L(1) = 2-(2-aminoethyl)-pyridine; L(2) = 2-(N-ethyl-2-aminoethyl)-pyridine; L(3) = 3,3'-iminobis(N,N-dimethylpropylamine)], respectively, were synthesized and characterized. Addition of nitric oxide gas to the degassed acetonitrile solution of the complexes were found to result in the reduction of the copper(II) center to copper(I). In cases of complexes 1 and 2, the formation of the [Cu(II)-NO] intermediate prior to the reduction of Cu(II) was evidenced by UV-visible, solution FT-IR and X-band EPR spectroscopic studies. However, for complex 3, the formation of [Cu(II)-NO] has not been observed. DFT calculations on the [Cu(II)-NO] intermediate generated from complex 1 suggest a distorted square pyramidal geometry with the NO ligand coordinated to the Cu(II) center at an equatorial site in a bent geometry. In the case of complex 1, the reduction of the copper(II) center by nitric oxide afforded ligand transformation through diazotization at the primary amine site in acetonitrile solution; whereas, in an acetonitrile-water mixture, it resulted in 2-(pyridine-2-yl)ethanol. On the other hand, in cases of complexes 2 and 3, it was found to yield N-nitrosation at the secondary amine site in the ligand frameworks. The final organic products, in each case, were isolated and characterized by various spectroscopic studies.  相似文献   
159.
Three copper(ii) complexes with bidentate ligands L(1), L(2) and L(3) [L(1), N,N(/)-dimethylethylenediamine; L(2), N,N(/)-diethylethylenediamine and L(3), N,N(/)-diisobutylethylenediamine], respectively, were synthesized as their perchlorate salts. The single crystal structures for all the complexes were determined. The nitric oxide reactivity of the complexes was studied in acetonitrile solvent. The formation of thermally unstable [Cu(II)-NO] intermediate on reaction of the complexes with nitric oxide in acetonitrile solution was observed prior to the reduction of copper(II) centres to copper(I). The reduction was found to result with a simultaneous mono- and di-nitrosation at the secondary amine sites of the ligand. All the nitrosation products were isolated and characterized. The ratio of the yield of mono- and di-nitrosation product was found to be dependent on the N-substitution present in the ligand framework.  相似文献   
160.
The effects of high Frequency (HF) progressive ultrasonic wave on the F-centers in KCl single crystals are discussed in this paper. Ultrasonics of 3 MHz and 9 MHz are used in the present investigation to produce strain wave perturbation on the F-centers. The thermoluminescence (TL) glow curves obtained from X-irradiated normal and strain wave exposed KCl single crystals show two peaks. In the TL glow curves recorded from X-irradiation followed by the ultrasonic wave exposure of KCl single crystals result in the shift of these peaks to higher temperature side with an increase in their separation and a change in relative areas. However, no additional peaks were seen. Apart from this the strain wave perturbation was also found to effect trapping parameters.  相似文献   
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