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41.
Neural Computing and Applications - Patient falls due to unattended bed-exits are costly to patients, healthcare personnel and hospitals. Numerous researches based on up to three predetermined...  相似文献   
42.
A true three-dimensional cone-beam reconstruction (TTCR) algorithm for direct volume image reconstruction from 2-D cone-beam projections is developed for the complete sphere geometry. The algorithm is derived from the parallel-beam true three-dimensional reconstruction (TTR) algorithm and is based on the modified filtered backprojection technique, which uses a set of 2-D space-invariant filters. The proposed algorithm proved to be superior in spatial resolution to the parallel-beam TTR algorithm and to offer better computational efficiency.  相似文献   
43.
Wireless Personal Communications - The expansion of information technology has led to a new form of banking. Traditional banking, based on the physical presence of the customer, is only a part of...  相似文献   
44.
Sodium and calcium petroleum sulphonates have been prepared by sulphuric acid treatment of the Egyptian Morgan 350–450 °C petroleum fraction. Extraction and purification of the sulphonates from the sulphonated oil and the residual acid sludge is described. Corrosion studies revealed that the sodium petroleum sulphonates are more effective as corrosion inhibitors than the calcium salts in a neutral as well as in an acid medium. A maximum inhibition efficiency of about 75% was obtained by the sodium salt in an acid and a neutral medium, while the relevant value obtained by the calcium salt is 60 and 23% in an acid and a neutral medium respectively. It has been also found that both salts accelerated corrosion when used at relatively high concentration in a neutral medium. Results are discussed according to the current views of corrosion inhibition.  相似文献   
45.
Microbial fuel cells are a type of bio-electrochemical system which can capture electrons produced by microorganisms. In this study, it is aimed to increase the electrogenic capacity of photosynthetic microbial fuel cells in a newly designed fuel cell. Rhodobacter sphaeroides, non-sulfur purple bacterium, was grown in anodic part of the fuel cells against permanganate as a cathodic electrolyte. Platine and graphite were used as the anodic and cathodic electrode, consequently. The distance between two electrodes was 1.5 cm. The concentrations of cathodic electrolyte were optimized. By the end, it is made to reach the highest anode potential (1.006 V) and electrogenic capacity (851.82 μA) in 5 mM permanganate concentration. The internal resistance was calculated as 1170 Ω. In these conditions, the current density with 2.1 cm2 cathodic surface is 405.63 mA/m2. These are the highest value of electricity generation potential of R. sphaeroides within the known PMFCs.  相似文献   
46.
The electronic and thermoelectric properties of biaxially strained magnesium silicide Mg2Si are analyzed by means of first-principle calculations and semiclassical Boltzmann theory. Electron and hole doping are examined for different doping concentrations and temperatures. Under strain the degeneracy of the electronic orbitals near the band edges is removed, the orbital bands are warped, and the energy gap closes up. These characteristics are rationalized in the light of the electron density transfers upon strain. The electrical conductivity increases with the biaxial strain, whereas neither the Seebeck coefficient nor the power factor (PF) follow this trend. Detailed analysis of the evolution of these thermoelectric properties is given in terms of the in-plane and cross-plane components. Interestingly, the maximum value of the PF is shifted towards lower temperatures when increasingly intensive strain is applied.  相似文献   
47.
The main objective of this study is to design and build an affordable solar thermoelectric refrigerator for the Bedouin people (e.g. deserts) living in remote parts of Oman where electricity is still not available. The refrigerator could be used to store perishable items and facilitate the transportation of medications as well as biological material that must be stored at low temperatures to maintain effectiveness. The design of the solar-powered refrigerator is based on the principles of a thermoelectric module (i.e., Peltier effect) to create a hot side and a cold side. The cold side of the thermoelectric module is utilized for refrigeration purposes; provide cooling to the refrigerator space. On the other hand, the heat from the hot side of the module is rejected to ambient surroundings by using heat sinks and fans. The designed solar thermoelectric refrigerator was experimentally tested for the cooling purpose. The results indicated that the temperature of the refrigeration was reduced from 27 °C to 5 °C in approximately 44 min. The coefficient of performance of the refrigerator (COPR) was calculated and found to be about 0.16.  相似文献   
48.
49.
Human fall detection (FD) acts as an important part in creating sensor based alarm system, enabling physical therapists to minimize the effect of fall events and save human lives. Generally, elderly people suffer from several diseases, and fall action is a common situation which can occur at any time. In this view, this paper presents an Improved Archimedes Optimization Algorithm with Deep Learning Empowered Fall Detection (IAOA-DLFD) model to identify the fall/non-fall events. The proposed IAOA-DLFD technique comprises different levels of pre-processing to improve the input image quality. Besides, the IAOA with Capsule Network based feature extractor is derived to produce an optimal set of feature vectors. In addition, the IAOA uses to significantly boost the overall FD performance by optimal choice of CapsNet hyperparameters. Lastly, radial basis function (RBF) network is applied for determining the proper class labels of the test images. To showcase the enhanced performance of the IAOA-DLFD technique, a wide range of experiments are executed and the outcomes stated the enhanced detection outcome of the IAOA-DLFD approach over the recent methods with the accuracy of 0.997.  相似文献   
50.
α-Amylase (EC 3.2.1.1; α-d-1,4,glucan glucanohydrolase) catalyzes the hydrolysis of α-d-(1,4)-glucosidic linkages in starch, glycogen, and various malto-oligosaccharides, by releasing α-anomeric products. In this study, a novel method has been developed to prepare nanoprotein particles that carry α-amylase as a monomer by using a photosensitive microemulsion polymerization process. The nanostructured α-amylase with photosensitive features have been characterized by fluorescence spectroscopy, transmission electron microscopy (TEM) and Zeta Sizer. The fluorescence intensity of amylase nanoparticles was determined to be 658 a.u. at 610 nm and the average particle size of nanoamylase was found to be about 71.8 nm. Both free α-amylase and nanoparticles were used in the hydrolysis of starch under varying reaction conditions such as pH and temperature that affect enzyme activity and the results were compared to each other. Km values were 0.26 and 0.87 mM and Vmax values were 0.36 IU mg? 1 and 22.32 IU mg? 1 for nanoenzyme and free enzyme, respectively. Then, thermal stability, storage stability and reusability were investigated and according to the results, activity was preserved 60% at 60 °C; 20% at 70–80 °C temperature values and 80% after 105 days storage. Finally after 10 cycles, the activity was preserved 90% and this novel enzymatic polymeric amylase nanoparticle has showed considerable potential as reusable catalyst.  相似文献   
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