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51.
Wireless Personal Communications - Due to using wireless sensor nodes (WSNs) in inaccessible areas and applying limitations in making nodes to reduce costs, these networks are prone to faults. The...  相似文献   
52.
The Journal of Supercomputing - Network on chip (NoC) has been of great interest in recent years. However, according to the recent studies, high communication cost has been raised as the one most...  相似文献   
53.
This study reports the effect of particle mass compositions on the bed expansion behaviour of a binary solid liquid fluidised bed (SLFB) system. Experiments were performed comprising equal density (2230 kg m?3) spherical glass beads particles of diameter 3, 5 and 8 mm and water as fluidising medium with different particle mass ratios varying from 0.17 to 6.0. In the expanded bed, both segregated and intermixed zones were observed depending on the different particle diameter combinations. In a completely segregated SLFB, the bottom monosized layer exhibited a negative deviation ~23% whereas a positive deviation ~25% was found in the top monosized layer when compared with the corresponding pure monosized system. A small mixing zone spanning approximately two particle diameters thick was observed to exist even in a completely segregated SLFB for higher diameter ratio cases. A slight decrease in the mixing zone height was noted with increasing liquid superficial velocity. For lower diameter ratio cases, a relatively lager mixing zone height was observed which increased with increasing liquid superficial velocity. The bed expansion ratio was noted to decrease with increasing solid mass ratio however it increased with increase in the fluidising velocity ratio following a reasonable power law trend. The expanded bed height of the binary mixture was not entirely additive of its corresponding mono-component bed heights and both positive and negative deviations were observed. Finally, a two-dimensional (2D) Eulerian-Eulerian (E-E) model incorporating the kinetic theory of granular flow (KTGF) was used to quantify the binary system hydrodynamics. The model predicted expanded bed height agreed with experimental measurements within ±6% deviation. Presence of a mixing zone was also confirmed by the CFD model and simulated particle phase volume fraction distribution qualitatively agreed with the experimental visualisations.  相似文献   
54.
This study examines the oxygen adsorption and desorption characteristics of La0.5Sr0.5Co0.8Fe0.2O3?δ (LSCF5582) membranes prepared at sintering temperatures of 1200–1300 °C, with the aim of gaining an insight into their performance in the surface reaction limited regime for oxygen separation applications. The findings of this work are then compared with our experimental data on Ba0.5Sr0.5Co0.8Fe0.2O3?δ (BSCF5582) membranes. It is demonstrated that the adsorption rate constants of both membranes are two orders of magnitude greater than their respective oxygen desorption rate constants as the oxygen adsorption occurs in less than 24 s whilst the oxygen desorption takes approximately one hour to reach equilibrium. The activation energy for oxygen adsorption of LSCF5582 reduced to a quarter of its value with increasing the sintering temperature from 1200 °C to 1300 °C. This is attributed to the oxygen exchange occurring more rapidly along the grain boundaries resulting in a lower activation energy. The LSCF5582 grain sintered at 1200 °C is the optimum selection for oxygen separation applications at an operating temperature of 850 °C and oxygen partial pressure of 0.21 bar.  相似文献   
55.
Neural Computing and Applications - Estimating the uniaxial compressive strength (UCS) of travertine rocks with an indirect modeling approach and machine learning algorithms is useful as models can...  相似文献   
56.
Multimedia Tools and Applications - Nowadays, due to widespread usage of the Internet, digital contents are distributed quickly and inexpensively throughout the world. Watermarking techniques can...  相似文献   
57.
In the knowledge economy, human capital is a key factor in any organization to achieve a sustainable competitive advantage. Thus, selection of competent personnel is the most important function of human resource managers. However, because of a wide range of criteria and organizational factors that affect the process, personnel selection is often regarded as a complex problem that can be answered through multicriteria decision‐making (MCDM) procedures. Despite the great importance of determining a comprehensive set of criteria, it has not gained enough attention in the literature. This study presents a competency framework with five criteria for choosing the best information technology (IT) expert from five alternatives. The stepwise weight assessment ratio analysis (SWARA) and grey additive ratio assessment (ARAS‐G) methods are also used to derive the criteria weights and provide the final alternative, respectively. The results reveal that subject competency is the major criteria in IT personnel selection.  相似文献   
58.
Photonic Network Communications - Based on the recent research, the communication cost has been the most important open issue in network on chip (NoC). In other words, the lower the communication...  相似文献   
59.
60.
Because of the high level of chlorophyll-type compounds found in canola oil, bleaching is an important and critical step in the canola oil refining process. In this study, a new method for reducing the chlorophyll-type impurities prior to the bleaching step was developed. This method is based on precipitating the chlorophyll compounds with mineral acids. Concentrations of chlorophyll-type compounds of up to 30 ppm could be reduced to amounts of less than 0.01 ppm by mixing the crude canola oil with a 0.4 wt% mixture of phosphoric and sulfuric acids (2:0.75, vol/vol) for 5 min at 50°C. Centrifugation and filtration also were examined as two main methods for separating the chlorophyll precipitates. The results showed that filtration by a precoated textural filter with filter-aid clay could separate the precipitates as well as the centrifugation method.  相似文献   
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