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81.
82.
In the 21st century, all the major countries around the world are coming together to reduce the impact of energy generation and consumption on the global environment. Energy conservation and its efficient usage has become a top agenda on the desks of many governments. In the last decade, the drive to make homes automated and to deliver a better assisted living picked pace and the research into home automation systems accelerated, usually based on a centralized residential gateway. However most devised solutions fail to provide users with information about power consumption of different house appliances. The ability to collect power consumption information can lead us to have a more energy efficient society. The goal addressed in this paper is to enable residential gateways to provide the energy consumption information, in a machine understandable format, to support third party applications and services. To reach this goal, we propose a Semantic Energy Information Publishing Framework. The proposed framework publishes, for different appliances in the house, their power consumption information and other properties, in a machine understandable format. Appliance properties are exposed according to the existing semantic modeling supported by residential gateways, while instantaneous power consumption is modeled through a new modular Energy Profile ontology.  相似文献   
83.
Copper and zinc ions were removed from synthetic acidic aqueous solutions onto cement kiln dust (CKD) particles in a single component system. The objectives of this study were to: distinguish between adsorption and precipitation when both mechanisms are occurring simultaneously; define their individual contributions; and consequently, specify the dominant mechanism. This was achieved by conducting a new experimental procedure for the precipitation phase that depended on CKD leachate in combination with a derivation of a simultaneous adsorption-precipitation equation. High removal efficiencies, approaching 100?%, of the Cu and Zn ions, were attained. Precipitation was the dominant mechanism for removing low concentrations of these metals, while adsorption appears to be more significant in removal of high metal concentrations.  相似文献   
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85.
Abstract

The results of an experimental study on clear-water scour at long skewed rectangular piers under steady flows at threshold velocity are presented. The scour mechanisms due to skewness effects with a wide range of angle of attack, α, and two sizes of uniform cohesionless bed sediment (d50 = 0.23 and d50 = 0.80 mm) have been investigated in a 50-m-long, 1.5-m-wide, and 2.0-m-deep flume. Empirical relation to demonstrate the effects of skewness in terms of dimensionless variables, such as aspect ratio (L/b), the angle of attack (α), flow shallowness (y/Bα), sediment coarseness (Bα/d50), the sediment gradation coefficient (σg), on scour depth is presented. The empirical relation is focused on predicting the angle of attack factor, Kα. The experimental data obtained in this study and data available from the literature were used to validate the predictions of existing methods and the accuracy of the proposed method. The proposed method gives reasonable scour depth predictions and was verified with statistical methods where the mean error was reduced from 53.6 to 18.1%.  相似文献   
86.
As the loadings of precious metals in surface-chemical systems continue to decrease for photo-and electro-catalysts for energy and environmental applications, the study of near-surface electronic and atomic structure in functional materials becomes critically important. Extremely small quantities of active elements, whether grown as clusters or ultrathin films, exhibit changes in catalytic activity that arise from both size effects and electron-transfer effects. These size and transfer effects can be related to increased propensity for oxidation of the metallic deposit, as well as to various changes in electrochemical performance such as durability or required overpotential for a given reaction. This work establishes a minimum threshold for Pt loading beyond which bulk-type electronic behavior may be expected. By iteratively growing atomic monolayers and multilayers using self-limited electrodeposition and studying these films using core-electron spectroscopy (X-ray absorption and X-ray photoelectron spectroscopy), electrochemical methods and DFT-based computations the fundamental interactions that govern oxidation state and electron transfer near the surface of a Pt–Au bimetallic system have been explored. It has been shown that the Pt–Au system exhibits increased tendency for the Pt layer to remain cationic below a minimum threshold film thickness of two monolayers. At monodispersed levels of submonolayer coverage Pt exhibits deviated electronic structure, reactivity, and metal stability compared to films in excess of this minimum threshold thickness. At three monolayers Pt is thick enough to avoid the preference for cationicity and the resulting higher rates of metal dissolution, but thin enough to benefit from electron transfers from Au that assist in lowering the overpotentials for CO oxidation. This study shows the efficacy of a concerted method for the investigation of near-surface phenomena in multicomponent systems. By combining electrochemical and vacuum studies of solute-derived samples with advanced computational techniques, a multifaceted understanding of these architectures has been achieved.  相似文献   
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88.
Both α- and β-thalassaemia syndromes are public health problems in the multi-ethnic population of Malaysia. To molecularly characterise the α- and β-thalassaemia deletions and mutations among Malays from Penang, Gap-PCR and multiplexed amplification refractory mutation systems were used to study 13 α-thalassaemia determinants and 20 β-thalassaemia mutations in 28 and 40 unrelated Malays, respectively. Four α-thalassaemia deletions and mutations were demonstrated. −−SEA deletion and αCSα accounted for more than 70% of the α-thalassaemia alleles. Out of the 20 β-thalassaemia alleles studied, nine different β-thalassaemia mutations were identified of which βE accounted for more than 40%. We concluded that the highest prevalence of (α- and β-thalassaemia alleles in the Malays from Penang are −−SEA deletion and βE mutation, respectively.  相似文献   
89.
Carbon fiber reinforced aluminum laminates (CARALL) are one of the aluminum based Fiber metal laminates (FMLs) which, due to their high strength to weight ratio and good impact resistance are greatly replacing aluminum alloys in aircraft structures. In this research work, interlaminate shear strength of Vacuum assisted resin transfer molding (VARTM) manufactured CARALL has been investigated. Numerical simulation model incorporated with real time material data has been developed to predict the delamination behavior of CARALL laminates. Standard CARALL specimens with different surface morphologies were prepared by electric discharge machining, mechanical, chemical and electrochemical surface treatments. T-peel tests were carried out according to standard ASTM D1876-08 to find out inter laminate shear strength. FMLs made out of mechanically, chemically and electrochemically cleaned metal sheets depicted high interlaminate shear strength. SEM micrographs of failed surfaces verify the high adhesive strength of epoxy. Developed numerical simulation model accurately predicts the delamination behavior of CARALL as observed during experimentation.  相似文献   
90.
The long-term performance of a bioaugmented membrane bioreactor (MBR) containing a GAC-packed anaerobic zone for treatment of textile wastewater containing structurally different azo dyes was observed. A unique feeding strategy, consistent with the mode of evolution of separate waste streams in textile plants, was adopted to make the best use of the GAC-zone for dye removal. Dye was introduced through the GAC-zone while the rest of the colorless media was simultaneously fed through the aerobic zone. Preliminary experiments confirmed the importance of coupling the GAC-amended anaerobic zone to the aerobic MBR and also evidenced the efficacy of the adopted feeding strategy. Following this, the robustness of the process under gradually increasing dye-loading was tested. The respective average dye concentrations (mg/L) in the sample from GAC-zone and the membrane-permeate under dye-loadings of 0.1 and 1 g/L.d were as follows: GAC-zone (3, 105), permeate (0, 5). TOC concentration in membrane-permeate for the aforementioned loadings were 3 and 54 mg/L, respectively. Stable decoloration along with significant TOC removal during a period of over 7 months under extremely high dye-loadings demonstrated the superiority of the proposed hybrid process.  相似文献   
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