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41.
LCNO (Li0.35Cr0.10Ni0.55O) sample was prepared by modified sol–gel method and annealed at different temperatures (400, 800 and 1000 °C) in order to have variation in the size of grains and grain boundaries. The crystallinity and phase purity have been studied by employing the X-ray diffraction (XRD) technique. All the samples are crystallize to cubic symmetry with \(Fm\overline 3 m\) space group and, XRD patterns could be analysed by employing the Rietveld method. The microstructural and elemental analysis of the sample has been carried out by using the field emission scanning electron microscopy (FESEM). The grain size increases with the increase in annealing temperature which leads to increase the dielectric constant with the grain size. Interestingly, the enhancement of dielectric constant with the increase in grain size could be explained by the Barrier Layer Capacitances (BLCs) model. The frequency dispersion of dielectric constant could be explained by the Maxwell Wagner relaxation model. Furthermore, it is also observed that the activation energy obtained from dielectric relaxation analysis is comparable with the activation energy obtained by impedance analysis (Cole–Cole). In addition, the correlation between microstructure (grains and grain boundaries) with electrical transport properties of LCNO has been reported.  相似文献   
42.
In manufacturing industries, the facility layout design is a very important task, as it is concerned with the overall manufacturing cost and profit of the industry. The facility layout problem (FLP) is solved by arranging the departments or facilities of known dimensions on the available floor space. The objective of this article is to implement the firefly algorithm (FA) for solving unequal-area, fixed-shape FLPs and optimizing the costs of total material handling and transportation between the facilities. The FA is a nature-inspired algorithm and can be used for combinatorial optimization problems. Benchmark problems from the previous literature are solved using the FA. To check its effectiveness, it is implemented to solve large-sized FLPs. Computational results obtained using the FA show that the algorithm is less time consuming and the total layout costs for FLPs are better than the best results achieved so far.  相似文献   
43.
The tetrapodal ligand 1,1,1,1-tetrakis[(salicylaldimino)methyl]methane (H4tsam) has been introduced for the first time for metal complexation. Two zinc(II) complexes[Zn2(tsam)] (1) and [Zn3(Htsam)2]·2C7H8 (2) have been obtained by reacting zinc acetylacetonate with the ligand in the presence of triethylamine, while a cobalt(III) complex [Co(Htsam)]·CH3CN·H2O (3) is obtained when Co(ClO4)2·6H2O is reacted in air. All the compounds have been characterized by their elemental analyses and ESI-MS, IR, UV-VIS and 1H NMR spectra. The X-ray crystal structures of H4tsam, 2 and 3 have been determined. Compounds 1 and 2 exhibit fluorescence in solution and the lifetimes of their luminescence decay have been measured. Thermal analysis (TGA, DTA) of 2 with regard to loss of encapsulated toluenes and redox behaviour of 3 have been studied.  相似文献   
44.
Effect of heat treatment involved in domestic cooking on the bioaccessibility of β‐carotene from yellow‐orange as well as green leafy vegetables was evaluated. Heat treatment of these vegetables by pressure‐cooking, stir‐frying and open‐pan boiling had a beneficial influence on the bioaccessibility of β‐carotene. The extent of increase in the per cent bioaccessibility of β‐carotene as a result of pressure‐cooking was 21–84%. Stir‐frying in presence of a small quantity of oil brought about an enormous increase in the bioaccessibility of β‐carotene from these vegetables, the extent of increase being 67–191%. Open‐pan boiling of vegetables increased the bioaccessibility of β‐carotene in the range 23–36%. Thus, among the three domestic heat processing methods, stir‐frying results in maximum bioaccessibility of this provitamin. The use of suitably heat‐processed vegetable sources of β‐carotene could form a dietary strategy to derive this micronutrient maximally by the population dependent on plant foods.  相似文献   
45.
This article presents a low hardware complexity for exponent calculations based on CORDIC. The proposed CORDIC algorithm is designed to overcome major drawbacks (scale-factor compensation, low range of convergence and optimal selection of micro-rotations) of the conventional CORDIC in hyperbolic mode of operation. The micro-rotations are identified using leading-one bit detection with uni-direction rotations to eliminate redundant iterations and improve throughput. The efficiency and performance of the processor are independent of the probability of rotation angles being known prior to implementation. The eight-staged pipelined architecture implementation requires an 8?×?N ROM in the pre-processing unit for storing the initial coordinate values; it no longer requires the ROM for storing the elementary angles. It provides an area-time efficient design for VLSI implementation for calculating exponents in activation functions and Gaussain Potential Functions (GPF) in neural networks. The proposed CORDIC processor requires 32.68% less adders and 72.23% less registers compared to that of the conventional design. The proposed design when implemented on Virtex 2P (2vp50ff1148-6) device, dissipates 55.58% less power and has 45.09% less total gate count and 16.91% less delay as compared to Xilinx CORDIC Core. The detailed algorithm design along with FPGA implementation and area and time complexities is presented.  相似文献   
46.
Four transition metal nanoparticles (TMNs) of 3d series (Cu, Co, Ni, and Fe) were prepared by hydrazine reduction of metal chloride in ethylene glycol at 60°C and characterized by X-ray diffraction (XRD). The XRD pattern showed average particle sizes for Cu, Ni, Co, and Fe of 16.7, 40.5, 27.4, and 35.0 nm, respectively. The activity of these TMN accelerants on the thermal decomposition of ammonium perchlorate (AP) was investigated using thermogravimetry (TG), differential scanning calorimetry (DSC), and ignition delay studies. Isothermal TG data were used to evaluate the kinetic parameters by model fitting as well as an isoconversional methods. The activation energy for thermal decomposition of AP was found to be 66.8, 68.7, 78.5, and 85.4 kJmol?1, respectively, for Co, Cu, Ni, and Fe, when they were mixed with AP. Hence, the order of activity was found to be Co > Cu > Ni > Fe. The accelerant effect of nanoparticles of TMNs was found to be better than their respective nano-oxides.  相似文献   
47.
The rapid growth in demand for data and the emerging applications of Big Data require the increase of memory capacity. Magnetic memory devices are among the leading technologies for meeting this demand; however, they rely on the use of ferromagnets that creates size reduction limitations and poses complex materials requirements. Usually magnetic memory sizes are limited to 30–50 nm. Reducing the size even further, to the ≈10–20 nm scale, destabilizes the magnetization and its magnetic orientation becomes susceptible to thermal fluctuations and stray magnetic fields. In the present work, it is shown that 10 nm single domain ferromagnetism can be achieved. Using asymmetric adsorption of chiral molecules, superparamagnetic iron oxide nanoparticles become ferromagnetic with an average coercive field of ≈80 Oe. The asymmetric adsorption of molecules stabilizes the magnetization direction at room temperature and the orientation is found to depend on the handedness of the chiral molecules. These studies point to a novel method for the miniaturization of ferromagnets (down to ≈10 nm) using established synthetic protocols.  相似文献   
48.
Wireless Personal Communications - In this paper numerical integration techniques are used to derive an approximation to $$Q(a\sqrt{\gamma })Q(b\sqrt{\gamma })$$ . Further this approximation is...  相似文献   
49.
Reliable data is needed to understand financial relationships in the power sector. However, relevant data acquisition and visualization can be a challenge due to the fragmented nature of the power sector. The US DOE and ORNL leveraged a Sankey prototype to elucidate the ‘big picture’ of financial flows to understand the complex relationships between specific actors within the power sector. The continued incorporation of high quality data can improve the fidelity of such an approach and lead to an increasingly detailed understanding of financial relationships in the power sector and their implications for policymakers.  相似文献   
50.
Karmakar  Supriya 《SILICON》2019,11(6):2775-2788
Silicon - The generation of four states in their transfer characteristic of QDG-QDCFET makes them useful to implement four state logic or quaternary logic. On the other hand, the number of device...  相似文献   
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