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121.
CoSn4 nano-particles were synthesized on Cu and Ni substrates through pulsed current electrodeposition and used as anode in lithium ion batteries. Nano particles with Flower-like morphology were obtained through applying an average current density of 85 mA/cm2 on Ni substrate while the particles formed using constant current electrodeposition are greater in size ca. 500 nm. Optimum discharge capacity of synthesized CoSn4 was obtained 848 mAh g?1 which reduced to 500 mAh g?1 at 120th cycle indicating an enhanced electrochemical performance compared to anode films synthesized through other pulsed current densities and also constant current electrodeposition. This high discharge capacity and cycleability is attributed to finer crystal grains and flower-like morphology of nano particles. Also, the sample synthesized on Ni substrate showed higher cycleability and noticeably lower resistance. High resistance of anode film synthesized on Cu substrate is due to the corrosion and passivation of copper occurred by HF formation in LiPF6 electrolyte.  相似文献   
122.
This paper provides a new methodology for the evaluation of the tangible benefits of information networks, based on their utilization and performance. The methodology enables the evaluation of different tangible benefits including those resulting from time, movement, paper, and space savings. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
123.
This paper presents a methodology for the analysis of the cost‐effectiveness of information networks over a period of time. The cost‐effectiveness is considered to be associated with use‐dependent and use‐independent costs and benefits. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
124.
Granulated blast furnace slag has been widely used as a partial substitute for Portland cement in many applications because of advantages which include cost reduction, reduction in heat evolution and improvement of durability properties. However, the effectiveness of slag depends on its hydraulic reactivity. In this paper, the results of an experimental study on the effect of slag with low hydraulicity on the mechanical and durability properties of concrete and the performance of mortar under sulfate attack are discussed. Special attention is given to gas permeability and water absorption of slag concrete. The durability of slag concrete is improved at long term at low Water/Binder ratio. Sulfate resistance of mortar is improved by slag replacement up to 30%.  相似文献   
125.
Biomass should be considered as one of the promising sources of energy for mitigating greenhouse gas (GHG) emissions. Co-firing biomass with coal has become a solution for meeting the power crisis as well as to reduce the pollutant emissions. The biomass fuels typically found from woody to grassy and solid recovered fuels depending on its origin and properties. It is suggested that co-firing coal with biomass has a substantial effect on SOx and NOx emission level. The ashing process, fly ash quality depends on the conversion technology, capture technology and the properties of the biomass. In order to control the furnace efficiency and production, burnout, optimum injection of biomass sharing with specific information of particle ignition properties are also important. A number of small/laboratory scale and industrial scale experiments have been conducted by different researchers. Different experimental studies performed are reviewed, grouped and summarized based on the fuel processing technology, burnout performance, emission level, environmental aspect, ash information and deposit characteristics, effect of co-firing ratios and adoption of oxy-fuel co-firing. Overall, this paper will highlight existing technologies and emerging trends in co-firing of different types of biomass which will be helpful for future investigations.  相似文献   
126.
Food Science and Biotechnology - Recently, considerable attention has been paid to drug exploration from natural sources for treating memory loss, a major manifestation of various neurodegenerative...  相似文献   
127.
Machines are key elements in manufacturing systems and their breakdowns can dramatically affect system performance measures. This paper proposes a new multi-objective pure integer linear programming approach for the cell formation problem with alternative process routings and machine reliability consideration. The model minimizes total cost and maximizes system reliability simultaneously. Traditional reliability evaluation approaches attempt to model the reliability of the manufacturing system as a function of its elements. These approaches have some negative aspects; therefore, instead of modeling the system reliability as an explicit objective function, we use an approach to model the effects of the machine unreliability in terms of cost and time-based effects. Using the ?-constraint method as an optimization tool for multi-objective programming, a numerical example is solved to demonstrate the capability of the proposed model in evaluating various effects of the reliability consideration.  相似文献   
128.
The aim of this paper is to present an extension of the original non-intrusive radioactive particle tracking method (RPT) to any geometries with irregular moving boundaries. The principal advantage of RPT over other non-intrusive methods is that it enables the visualization of rather large systems. However, the underlying reconstruction algorithm is limited to cylindrically shaped systems such as fluidized beds and columns. It excludes a wide variety of systems involving multiphase flows such as, for instance, spherical reactors, cyclones and powder silos, hoppers and blenders, all of which are thus currently out of reach of current RPT capabilities. This work addresses these limitations and proposes an approach that solves the inverse map problem to reconstruct the tracer position with time by using a mesh of unstructured cells to discretize the system geometry and kinematics. The anisotropy induced by the gas-solid interface is discussed and taken into account in the proposed model. To show the possibilities and assess the performance of the developed technique, the flow of particles in a 16-qt V-blender is mapped and the mean velocity field is computed.  相似文献   
129.
Poly(o-methoxyaniline) (POMA) salts doped with organic sulphonic acids (methanesulphonic acid, p-toluenesulphonic acid and dodecylbenzenesulphonic acid) were firstly synthesized by using solid-state polymerization method. The polymers were characterized by Fourier transform Infrared (FTIR) spectra, ultraviolet visible (UV–vis) spectrometry, X-ray diffraction (XRD), Cyclic Voltammetry (CV), and conductivity measurements. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were done to study the morphologies of POMA salts. The results showed that the POMA doped with methanesulphonic acid displayed higher doping level and conductivity. On the contrary, POMA doped with dodecylbenzenesulphonic acid was lower at doping level and conductivity. In accordance with these results, the electrochemical activity was also found to be lower in dodecylbenzenesulphonic acid doped POMA. The results also revealed that the particles of POMA salts have the average size of less than 100 nm.  相似文献   
130.
Designing a cellular manufacturing (CM) system involves three major decisions: cell formation (CF), cellular layout (CL), and cellular scheduling (CS). The integrated design of CM systems is investigated in this paper by proposing two mathematical models. The first model integrates cellular layout problem with cell formation problem to determine optimal cell configuration and the layout of machines and cells in order to minimize the total movement costs. The second model takes also the cellular scheduling into consideration with the objective of minimizing the total completion time of parts. Two genetic algorithms are developed to solve the real-sized problems. The proposed models are formulated as mixed integer linear programming, and two numerical examples are solved in order to investigate the effects of integration in the CM systems design. The results show that considering CF, CL, and CS decisions in a simultaneous manner can significantly improve the performance of the CM systems.  相似文献   
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