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11.
Adaptive neural net (ANN) model of hot metal desulphurization is first optimized by various search methods including the golden section search and Davies-Swann-Campey methods. Logarithmic preprocessing of input data leads to a further improvement in generalization ability of the net. Genetic adaptive search (GAS) method is used to optimize the mathematical model for desulphurization and when the input data are preprocessed with this optimized model and fed into an artificial neural net, the generalization ability of the net becomes even better. Best results are obtained when using GAS to optimize the interconnection weights during the training phase, while training data are preprocessed through a mathematical model already optimized by GAS. For every process several options presented by a combination of ANN and GAS must be systematically investigated before choosing the ultimate model for predictions on shop floor.  相似文献   
12.
Integrating biomass energy generation with carbon capture will result in “carbon neutral” to “carbon negative” technology. Countries like India and China possess significant reserves of limestone. Calcium looping (CaL) technology can prove to be a promising option for carbon capture in these countries. The present work aims at improving the performance of CaL‐integrated biomass‐fired power plant (BFPP) by exploring different looping configurations. In this study, (i) standalone BFPP, (ii) conventional CaL (single stage), and (iii) double CaL‐integrated BFPP have been systematically evaluated. A comparative performance evaluation of these three plants in terms of energy, exergy and ecological assessment, has been carried out. A detailed parametric study and unit‐wise exergy analysis of the best configuration among the three are presented to identify the scope for further improvement in efficiency and energy savings.  相似文献   
13.
Multimedia Tools and Applications - In this paper, an improved wavelet based medical image watermarking algorithm is proposed. Initially, the proposed technique decomposes the cover medical image...  相似文献   
14.
Controversies surround levothyroxine sodium as a drug and product, and are reflected in compendia (USP vs BP) differences in levothyroxine sodium tablets specifications concerning potency limit and dissolution test conditions, and in lack of consensus on several issues such as whether the drug BCS class I or III. We have recently published a clinical study in patients comparing the efficacy of multisource 100?mcg levothyroxine sodium tablets (three sources, two brands, a total of five batches). Clinical efficacy and dissolution rate data varied among the tablet batches studied and indicated that brand/source interchangeability could not be claimed. The efficacy parameters showed good correlation with dissolution data generated under BP 2014, but not under USP 2014 dissolution test conditions. In the present study, we decided to expand the number of tablet batches studied in vitro to a total of 12, to report potency and content uniformity data missing in the clinical study, and to further examine the discrepancy in dissolution results based on the medium used. The wide range of batch age in the studied samples allowed investigating the effect of batch age on in-vitro tablet performance parameters. Generated potency values indicated the prevalence of super-potent tablet batches. The dissolution data reflected the effect of compendia monograph differences in dissolution medium. The results also indicated an inverse relationship between tablet potency and batch age and, between dissolution and batch age. The possible effect of potency results on the generated dissolution data was discussed. Statistical significance of correlations examined was assessed by linear and non-linear regression analysis. Statistical significance was evident for the relation between batch age and BP 2014 dissolution data, compared to USP 2014 dissolution results.  相似文献   
15.
Building integrated photovoltaic thermal (BIPVT) system has the potential to become a major source of renewable energy in the urban environment. In this paper, the system has been used as the roof top of a building to generate higher electrical energy per unit area and to produce necessary thermal energy required for space heating. One-dimensional transient model has been developed using basic heat transfer equations. On the basis of this model, an analysis has been carried in order to select an appropriate BIPVT system suitable for the cold climatic conditions of India. The PV performances, net energy gain and exergy of the building are determined. The results show that for a constant mass flow rate of air the system connected in series gives a better performance whereas for a constant velocity of air flow the system connected in parallel gives a better performance. The BIPVT system, fitted on the rooftop in an effective area of 65 m2, is capable of annually producing the net electrical and thermal exergies of 16,209 kW h and 1531 kW h, respectively, at an overall thermal efficiency of 53.7%.  相似文献   
16.
Silk sericin (SS), a protein biopolymer, is gaining an increasing attention in a variety of biomedical applications. Our objective was to identify the optimal extraction method yielding the highest silk protein content, to assess its chemical elemental composition, to characterize it, and to compare its conformation by X-ray diffraction and Fourier-transform infrared versus that of the commercial one. Herein, alkali and high temperature is the perfect approach. This study aimed further to test whether extracted SS could attenuate the adverse hepatotoxic effects induced by diethylnitrosamine (DEN) in mice. Animals were injected intraperitoneally once weekly for four consecutive weeks with physiological saline (0.9% NaCl), DEN (25 mg/kg), SS (1 g/kg) 90 min prior to DEN injection, melatonin (10 mg/kg) followed within 1 h with the administration of SS and 30 min later with DEN. The results confirmed the hepatotoxicity of DEN manifested by an increase in liver enzymes' activity, and pathological changes in the liver tissue. The combined use of SS and/or melatonin with DEN returned most of the parameters to values similar to the controls. Briefly, chemically characterized SS seems a valuable extract for further consideration as anti-carcinogenic agent. It has the potential to upgrade liver cancer chemotherapeutic agents.  相似文献   
17.
This study investigates the free convective flow of heat generating/absorbing fluid between vertical parallel porous plates due to periodic heating of the porous plates. The analysis is performed by considering fully developed flow and steady-periodic regime. The momentum and energy equations, which arise from the definition of velocity and temperature, are written in dimensionless form. Separating the temperature and velocity fields into steady and periodic parts, the resulting second order differential equations are solved to obtain the expressions for velocity, temperature, skin friction and the rate of heat transfer. The effects of various flow parameters such as the suction/injection (s), heat source/sink (δ), Strouhal (St) and Prandtl (Pr) numbers on the skin friction coefficient, rate of heat transfer, velocity and temperature profiles are discussed with the aid of line graphs and contour maps.  相似文献   
18.
In this article, an exact solution is obtained to investigate the role of nonlinear Boussinesq approximation on mixed convection flow in a vertical channel subject to asymmetric wall heating. The nonlinear density variation with temperature (NDT) in the buoyancy term is introduced to the momentum equation and solved exactly by direct integration. During the course of graphical and numerical computations, results show that the role of NDT is to increase fluid velocity as well as skin‐friction while it reduces the rate of heat transfer. In addition, reverse flow formation at the walls is increased due to the inclusion of NDT (nonlinear Boussinesq approximation).  相似文献   
19.
Unsteady free convection and mass transfer flow past an accelerated infinite nonconducting vertical plate through a porous medium have been analyzed in the presence of a uniform magnetic field and constant heat source. Expressions for the velocity field for two different cases are obtained by the Laplace-transform technique. The influence of the various parameters entering into the problem on the velocity field is extensively discussed.  相似文献   
20.
Small extracellular vesicles isolated from urine (uEVs) are increasingly recognized as potential biomarkers. Meanwhile, different uEV preparation strategies exist. Conventionally, the performance of EV preparation methods is evaluated by single particle quantification, Western blot, and electron microscopy. Recently, we introduced imaging flow cytometry (IFCM) as a next-generation single EV analysis technology. Here, we analyzed uEV samples obtained with different preparation procedures using nanoparticle tracking analysis (NTA), semiquantitative Western blot, and IFCM. IFCM analyses demonstrated that urine contains a predominant CD9+ sEV population, which exceeds CD63+ and CD81+ sEV populations. Furthermore, we demonstrated that the storage temperature of urine samples negatively affects the recovery of CD9+ sEVs. Although overall reduced, the highest CD9+ sEV recovery was obtained from urine samples stored at −80 °C and the lowest from those stored at −20 °C. Upon comparing the yield of the different uEV preparations, incongruencies between NTA and IFCM data became apparent. Results obtained by both NTA and IFCM were consistent with Western blot analyses for EV marker proteins; however, NTA results correlated with the amount of the impurity marker uromodulin. Despite demonstrating that the combination of ultrafiltration and size exclusion chromatography appears as a reliable uEV preparation technique, our data challenge the soundness of traditional NTA for the evaluation of different EV preparation methods.  相似文献   
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