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751.
International Journal of Information Security - The growth of media services, multimedia conferencing, interactive distance learning, and distributed interactive simulations is becoming more...  相似文献   
752.
753.
The development of effective methods to utilize industrial and agricultural wastes is crucial from the perspective of a circular economy. Marble powder and olive pomace (OP), byproducts of olive oil production and marble processing, are considered one of the major sources causing severe environmental pollution, especially in Mediterranean countries. Herein, marble powder and OP are aimed to use as fillers in polypropylene (PP)-based polymer composite. In addition, fractionated OP is further fibrillated by a combination of mechanical grinding and ionic liquid treatment to enhance its performance as a reinforcement. After treatment for 24 h, the particle size decreases from about 2.1 to 1.1 µm, and the lignocellulosic composition also varies due to the partial removal of hemicellulose. Finally, the compounding ratio of polymer composites consisting of PP, marble powder, fibrillated OP, and compatibilizer is optimized using response surface methodology (RSM) to achieve both high mechanical properties and high filler contents. Mechanical properties of polymer composite fabricated with optimum ratio are in excellent agreement with those predicted by RSM. Furthermore, the yield strength and Young's modulus of polymer composite are 33.9 MPa and 1.89 GPa, accordingly, which are higher than those of PP.  相似文献   
754.
Diffusion of transition metals across the cathode–electrolyte interface is identified as a key challenge for the practical realization of solid-state batteries. This is related to the formation of highly resistive interphases impeding the charge transport across the materials. Herein, the hypothesis that formation of interphases is associated with the incorporation of Co into the Li7La3Zr2O12 lattice representing the starting point of a cascade of degradation processes is investigated. It is shown that Co incorporates into the garnet structure preferably four-fold coordinated as Co2+ or Co3+ depending on oxygen fugacity. The solubility limit of Co is determined to be around 0.16 per formula unit, whereby concentrations beyond this limit causes a cubic-to-tetragonal phase transition. Moreover, the temperature-dependent Co diffusion coefficient is determined, for example, D700 °C = 9.46 × 10−14 cm2 s−1 and an activation energy Ea = 1.65 eV, suggesting that detrimental cross diffusion will take place at any relevant process condition. Additionally, the optimal protective Al2O3 coating thickness for relevant temperatures is studied, which allows to create a process diagram to mitigate any degradation with a minimum compromise on electrochemical performance. This study provides a tool to optimize processing conditions toward developing high energy density solid-state batteries.  相似文献   
755.
A smart community grid is an electrical network, which connects several producers, consumers, and prosumers to share energy in an intelligent and secure way. The main challenges of smart community grid are demand response, demand bidding, dynamic electricity tariffs, demand-side management, and prosumers handling. The current state-of-the-art smart grid decision making is focused on consumers and producers behavior while the aim of this research is to achieve prosumer's different goals in an optimized and intelligent way. A genetic algorithm (GA)-based solution is proposed to share energy in an optimized way without affecting the prosumers' preferences. Six prosumers smart community grids data sets are used to validate the performance of the proposed system. The results show that the proposed method significantly improves the loss of energy sharing without compromising the user's preferences.  相似文献   
756.
Cadmium is an industrially applied plating metal used in aerospace applications, but electrodeposition of cadmium is toxic, and current production method will soon be banned. Therefore, electrodeposition of alternative alloys in environmentally friendly solutions is an attractive research area. An additive-free, nonaqueous, deep eutectic solvent (DES) containing Ni and Zn halide salts is developed in a greener environmental method. Gamma-phase nanocrystalline Ni2Zn11 is coated onto hot-rolled mild steel via pulse reverse current (PRC) in the developed nonaqueous solvent. The employed DES’ relatively low viscosity and sufficient conductivity enable the simultaneous reduction of Ni2+ and Zn2+ cations on microelectrode. Electrochemical quartz crystal microbalance (eQCM) analysis proves the absence of the commonly reported problem of electrode blocking during electrodeposition, revealing an efficiency of 86.07%. Appropriate PRC parameters are applied for scaled macroelectrode deposition. The plating profile exhibits 20 μm-thick alloy deposition without cracks around 3 h. Scanning electron microscopy–electron-dispersive spectroscopy and X-ray diffraction analyses reveal that 15.5 wt% Ni is in the nanograin phase, and all crystal planes belong to the γ-Ni2Zn11 phase, which is needed as an alternative to cadmium plating. Hardness and corrosion tests performed on the γ-Ni2Zn11 coating reveal better hardness and corrosion resistance with supporting morphological evidence.  相似文献   
757.
The polarization of light is a valuable information channel that has been studied extensively in optical devices. There has been limited progress in developing low-refractive index contrast and large-scale chiral meta-devices that are easy to integrate and mass-produce. In this image, a chiral imaging meta-device with a large area and broadband chirality control is experimentally demonstrated. The centimeter-scale Moiré meta-device is achieved using nanoimprint technology. The Poynting vector and singularity features in the near field and chiral optical response in the far field are discussed. The proposed Moiré meta-devices can achieve circular dichroism (CD) of more than 10%. Further chiral imaging harnessing CD mechanisms are demonstrated, which may lead to significant potential in various fields, including encryption and security, materials science, biochemistry, and medicine.  相似文献   
758.
Solar energy will be a great alternative to fossil fuels since it is clean and renewable. The photovoltaic (PV) mechanism produces sunbeams’ green energy without noise or pollution. The PV mechanism seems simple, seldom malfunctioning, and easy to install. PV energy productivity significantly contributes to smart grids through many small PV mechanisms. Precise solar radiation (SR) prediction could substantially reduce the impact and cost relating to the advancement of solar energy. In recent times, several SR predictive mechanism was formulated, namely artificial neural network (ANN), autoregressive moving average, and support vector machine (SVM). Therefore, this article develops an optimal Modified Bidirectional Gated Recurrent Unit Driven Solar Radiation Prediction (OMBGRU-SRP) for energy management. The presented OMBGRU-SRP technique mainly aims to accomplish an accurate and time SR prediction process. To accomplish this, the presented OMBGRU-SRP technique performs data preprocessing to normalize the solar data. Next, the MBGRU model is derived using BGRU with an attention mechanism and skip connections. At last, the hyperparameter tuning of the MBGRU model is carried out using the satin bowerbird optimization (SBO) algorithm to attain maximum prediction with minimum error values. The SBO algorithm is an intelligent optimization algorithm that simulates the breeding behavior of an adult male Satin Bowerbird in the wild. Many experiments were conducted to demonstrate the enhanced SR prediction performance. The experimental values highlighted the supremacy of the OMBGRU-SRP algorithm over other existing models.  相似文献   
759.
This study conducted in Lima, Peru, a combination of spatial decision making system and machine learning was utilized to identify potential solar power plant construction sites within the city. Sundial measurements of solar radiation, precipitation, temperature, and altitude were collected for the study. Gene Expression Programming (GEP), which is based on the evolution of intelligent models, and Artificial Neural Networks (ANN) were both utilized in this investigation, and the results obtained from each were compared. Eighty percent of the data was utilized during the training phase, while the remaining twenty percent was utilized during the testing phase. On the basis of the findings, it was determined that the GEP is the most suitable network for predicting the location. The test state’s Nash-Sutcliffe efficiency (NSE) was 0.90, and its root-mean-square error (RMSE) was 0.04. Following the generation of the final map based on the results of the GEP model, it was determined that 9.2% of the province’s study area is suitable for the construction of photovoltaic solar power plants, while 53.5% is acceptable and 37.3% is unsuitable. The ANN model reveals that only 1.7% of the study area is suitable for the construction of photovoltaic solar power plants, while 66.8% is acceptable and 31.5% is unsuitable.  相似文献   
760.
Prominence of color perception in our day-to-day routine is unequivocally pronounced, yet visual ramifications due to color vision deficiency (CVD) or color blindness impede carriers of this disorder from functioning normally. To circumvent this deficiency, patients opt for tinted glasses/contact lenses to complement their color distinction capabilities. Red-green color blindness, the most prevalent form of CVD, can be alleviated using such glasses/lenses that filter out problematic wavelengths (540–580 nm). Nonetheless, nearly all contact lenses established by companies and developed by researchers are tinted throughout their entire surface, causing patients discomfort and needless attention as people can easily note their deficiency. Ideally, the tint within the lens should only cover the eye's pupil as it is responsible for perceiving light. Hence herein, CVD contact lenses are fabricated by solely tinting the midportion of commercial lenses utilizing two additively manufactured molds with 4 and 8 mm-diameter holes to emulate the humans’ average pupil size. The tinted lenses filter light effectively at 530–590 nm with their transmission dip being at 558 nm. The contact lenses show excellent wettability and water retention capabilities along with demonstrating superior wavelength-filtering properties to most of the commercial and research-based CVD wearables.  相似文献   
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