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1.
This article presents a hybrid model involving artificial neural networks and biogeography-based optimization for long-term forecasting of India's sector-wise electrical energy demand. It involves socio-economic indicators, such as population and per capita gross domestic product, and uses two artificial neural networks, which are trained through a biogeography-based optimization algorithm with a goal of perfect mapping of the input–output data in the non-linear space through obtaining the global best weight parameters. The biogeography-based optimization based training of the artificial neural network improves the forecasting accuracy and avoids trapping in local optima besides enhancing the convergence to the lowest mean squared error at the minimum number of iterations than existing approaches. The model requires an input and the year of the forecast and predicts the sector-wise energy demand. Forecasts up to the year 2025 are compared with those of the regression model, the artificial neural network model trained by back-propagation, and the artificial neural network model trained by harmony search algorithm to exhibit its effectiveness.  相似文献   
2.
The gradual depletion of fossil fuels has greatly enhanced the necessity to look for alternative fuels for automobile engines. In response to this, biodiesel is being considered as a promising and potential alternative substitute to conventional petroleum diesel. However, long-term storage stability of biodiesel is poorer compared to conventional petroleum diesel. The aim of the project work is to study the long-term storage stability of biodiesel (B100) and its blend (B20) prepared from used frying oil in different conditions of storage. In this work, the effect of antioxidants and temperature on long storage stability of biodiesel obtained from with respect to storage period is analysed using response surface methodology (RSM). The long storage of biodiesel obtained from used frying oils were optimised by varying parameters such as antioxidant concentration, storage period by Box-Behnken RSM. The properties such as the acid value and the viscosity of biodiesel were initially measured. The results of the investigation showed that the addition of sufficient concentration of antioxidant (pyrogallol) significantly maintains the acid value and viscosity of biodiesel and helps to store for a longer storage period at the given storage temperature.  相似文献   
3.
Lipomannan and lipoarabinomannan are integral components of the mycobacterial cell wall. Earlier studies demonstrated that synthetic arabinan and arabinomannan glycolipids acted as inhibitors of mycobacterial growth, in addition to exhibiting inhibitory activities of mycobacterial biofilm. Herein, it is demonstrated that synthetic mannan glycolipids are better inhibitors of mycobacterial growth, whereas lipoarabinomannan has a higher inhibition efficiency to biofilm. Syntheses of mannan glycolipids with a graded number of mannan moieties and an arabinomannan glycolipid are conducted by chemical methods and subsequent mycobacterial growth and biofilm inhibition studies are conducted on Mycobacterium smegmatis. Growth inhibition of (73±3) % is observed with a mannose trisaccharide containing a glycolipid, whereas this glycolipid did not promote biofilm inhibition activity better than that of arabinomannan glycolipid. The antibiotic supplementation activities of glycolipids on growth and biofilm inhibitions are evaluated. Increases in growth and biofilm inhibitions are observed if the antibiotic is supplemented with glycolipids, which leads to a significant reduction of inhibition concentrations of the antibiotic.  相似文献   
4.
It has been noted in the past that economically sound, environmentally preferable life extension modes such as remanufacturing and recycling have special characteristics that complicate the management of their production, logistics and associated operations. This paper considers these complicating characteristics from the perspective of the nine different modes of product life extension. In doing so, a framework and guide is provided to what issues, resource requirements and management capabilities are required for specific life extension modes. This framework provides guidance to practitioners and academics on commonalities between different product life extension modes, thereby assisting practitioners in leveraging current internal skills and capabilities and researchers in determining the generalizability of research.  相似文献   
5.
A series of Gd100−xMnx (x = 0, 5, 10, 15, and 20 at.%) alloys were prepared by arc-melting. The Curie temperature (TC) associated with the ferromagnetic-paramagnetic transitions, derived from M-T curves, show decrease in TC for as-cast alloys (∼279 K) as compared to as-cast Gd (∼292 K). No appreciable decrease in the |ΔSM|max values ∼4.6 J/kg K (0-2 T) and ∼8.6 J/kg K (0-5 T) were observed upon alloying Gd with Mn up to x ≤ 15 at.%. Refrigerant capacity (q) showed negligible variation ∼195 J/kg (0-2 T) and ∼450 J/kg (0-5 T) with increasing Mn (up to x ≤ 15 at.%) content. Similar values of |ΔSM|max and q coupled with ∼13 K decrease in TC for as-cast Gd100−xMnx (0 ≤ x ≤ 15) alloys as compared to Gd, suggests expansion of working temperature region of Gd upon alloying with Mn up to 15 at.%. Low cost, adjustable TC, favorable magnetocaloric properties make Gd100−xMnx alloys potential candidates as second-order transition based magnetic refrigerants for near room temperature air-conditioning and magnetic refrigeration.  相似文献   
6.
The Sm3+ doped Y3?xSmxFe5O12 (x = 0–3) nanopowders were prepared using modified sol–gel route. The crystalline structure and morphology was confirmed by X-ray diffraction and atomic force microscopy. The nanopowders were sintered at 950 °C/90 min using microwave sintering method. The lattice parameters and density of the samples were increased with an increase of Sm3+ concentration. The room temperature dielectric (ε′ and ε″) and magnetic (μ′ and μ″) properties were measured in the frequency range up to 20 GHz. The room temperature magnetization studies were carried out using Vibrating sample magnetometer using filed of 1.5 T. Results of VSM show that the saturation and remnant magnetization of Y3?xSmxFe5O12 (0–3) decreases on increasing the Sm concentration (x). The low values of magnetic (μ′ and μ″) properties makes them a good candidates for microwave devices, which can be operated in the high frequency range.  相似文献   
7.
The nanocomposites of NiCuZnFe2O4-SiO2 were prepared using Microwave-Hydrothermal method at 160°C/45 min.The as-synthesized powders were characterized using X-ray diffraction and Transmission Electron Microscope (TEM).The average particle size of the powders were found to be ~20 nm.The powders were densified at 900°C/30 min using Microwave sintering method. The sintered composite samples were characterized using XRD and Scanning Electron Microscopy (SEM). Crystallite size of the ferrites decreases with an increase of SiO2 content. The density of the composites varies of 93–98% of theoretical density. The densities of the present composites were increasing with the addition of SiO2. The bulk densities of the present composites were increasing with the addition of SiO2. The structural changes in these samples were characterized using Fourier Transform Infrared Spectrometer (FTIR) in the 400–4000 cm?1. The bands in the range of 580–880 cm?1 show a slight increase in intensity, which could be ascribed to the enhanced interactions between the NiCuZnFe2O4 clusters and silica matrix. The resistivity of the sintered samples was increased with an addition of ferrite content. The real and imaginary parts of permittivity and permeability were measured in the frequency range of 1 MHz–1.8 GHz.The addition of SiO2 alters the values of dielectric constant and permeability which is useful to the Multilayer Chip Inductors (MLCI) fabrication.  相似文献   
8.
The combined effect of annular gap, yield stress and irreversible boundary reaction on the dispersion process in a Casson fluid flow is studied using generalized dispersion model. The study describes the development of dispersive transport following the injection of a tracer in terms of the three effective transport coefficients viz. absorption, convection and dispersion coefficients. The combined effect of annular gap, yield stress and wall absorption parameter on the above three effective transport coefficients is discussed. It is observed that the absorption coefficient is independent of the yield stress of the fluid and depends on the annular gap and wall absorption parameter. It is also observed that the asymptotic convection, dispersion coefficients are dependent on the yield stress of the fluid, annular gap and wall absorption parameter. The effect of the flow parameters on the mean concentration is studied. Application of this model for understanding the dispersion of solute in blood in a catheterized artery is discussed.  相似文献   
9.
We discuss smart environments that identify and track their occupants using unobtrusive recognition modalities such as face, gait, and voice. In order to alleviate the inherent limitations of recognition, we propose spatio-temporal reasoning techniques based upon an analysis of the occupant tracks. The key idea underlying our approach is to determine the identity of a person based upon information from a track of events rather than a single event. We abstract a smart environment by a probabilistic state transition system in which each state records a set of individuals who are present in various zones of the smart environment. An event abstracts a recognition step, and the transition function defines the mapping between states upon the occurrence of an event. We express two forms of spatio-temporal reasoning in the form of transition functions: a track-based transition function and an error-correcting transition function. We also define the concepts of ‘precision’ and ‘recall’ to quantify the performance of the smart environment and provide experimental results to clarify the performance improvements from spatio-temporal reasoning. Our conclusion is that the state transition system is an effective abstraction of a smart environment and the application of spatial-temporal reasoning enhances the overall performance of a biometric recognition system.  相似文献   
10.
This investigation focuses on slow, isothermal, two-phase flow of gas bubble suspensions in Separan solutions, prepared with the help of a sodium borohydride blowing agent at room temperature. The total residence time in these experiments is much smaller than characteristic times for growth or rise of bubbles. The variation of bubble volume fraction across a narrow gap between two planes, is recorded at two locations along the flow direction. This is done with a Cesium gamma-radiation source focused on a region of area.012 cm2 in the flow plane, and a Sodium iodide detector across the channel yielding a resolution of.01 over the range of void fractions investigated from.02 to.08. This measurement allows us to identify conditions under which the two-phase flow may be described by a two fluid model with a uniform bubbly core and a bubble free wall layer. With this two phase flow structure, a relative viscosity equation for the suspension is used to compute an apparent viscosity. Such calculations indicate that the observed reduction in apparent viscosity for the two phase flow may be attributed to a bubbly core which is more shear thinning than the medium. The additional shear thinning factor for the suspension is related to the elasticity of the medium.  相似文献   
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