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31.
    
The encapsulation process has been utilized in the field of food technology to enhance the technofunctional properties of food products and the delivery of nutraceutical ingredients via food into the human body. The latter application is very similar to drug delivery systems. The inherent sophisticated nature of release mechanisms requires the utilization of mathematical equations and statistics to predict the release behavior during the time. The science of mathematical modeling of controlled release has gained a tremendous advancement in drug delivery in recent years. Many of these modeling methods could be transferred to food. In order to develop and design enhanced food controlled/targeted bioactive release systems, understanding of the underlying physiological and chemical processes, mechanisms, and principles of release and applying the knowledge gained in the pharmaceutical field to food products is a big challenge. Ideally, by using an appropriate mathematical model, the formulation parameters could be predicted to achieve a specific release behavior. So, designing new products could be optimized. Many papers are dealing with encapsulation approaches and evaluation of the impact of process and the utilized system on release characteristics of encapsulated food bioactives, but still, there is no deep insight into the mathematical release modeling of encapsulated food materials. In this study, information gained from the pharmaceutical field is collected and discussed to investigate the probable application in the food industry.  相似文献   
32.
    
This study aims to improve the oxidative stability of olive oil using microformulated vitamin-C (Vit-C). The microemulsion containing 10,000 µg/ml Vit-C with a droplet size of 1,000 ± 68 nm was first prepared. Free radical scavenging of olive oil and olive oil containing blank microemulsion, different amounts of formulated Vit-C (100–500 µg/ml), and TBHQ (100 and 200 µg/ml as a standard antioxidant) was around 90% during 21 days of incubation at 60°C. The oxidative stability of the mentioned samples during incubation was investigated using the rancimat test, and their quality criteria analysis was studied by peroxide and the acid values. Results showed that the sample's acid value containing 500 µg/ml of Vit-C did not show significant differences (p < .05) with samples containing TBHQ. However, samples containing TBHQ's peroxide value were significant (p < .05) lower than samples containing 500 µg/ml of Vit-C. Furthermore, the induction time of samples containing 500 µg/ml of Vit-C was significantly (p < .05) higher than other treatments during incubation. Thus, the prepared microemulsion could be used as a natural antioxidant in the oil industry instead of harmful synthetic TBHQ.  相似文献   
33.
    
In Large Scale Systems the concept of centrality fails due to the lack of centralized computing capability. The control of such systems has to be performed using multiple control agents. In this case, the matter of interactions among neighboring subsystems needs to be considered. In this paper, a water control system in the Netherlands is studied as a real large scale system. A multi‐agent scheme is applied to control the flow through the system which is decomposed into two interconnected subsystems. Each agent employs a model‐based predictive control (MPC) technique. The model of this large scale system is nonlinear and nonconvex. Therefore, an augmented Lagrangian pattern search optimization algorithm is used to implement multi‐agent MPC for this system. This proposed algorithm is applied by each control agent to solve its own interconnected optimization problem, at each subsystem of whole the water system. Simulation results show the effectiveness of the proposed approach.  相似文献   
34.
    
Mixed matrix materials (MMMs) integrating excellent processability from polymers and distinct separation properties from nanofillers are of interest for membrane gas separations, and they are often made into freestanding films (>100 µm) to demonstrate superior gas separation properties. However, they are difficult to fabricate into thin-film nanocomposite (TFN) membranes due to interfacial incompatibility between polymers and nanofillers. Here TFN membranes based on MMMs (as thin as 200 nm) are successfully developed comprising amorphous poly(ethylene oxide) (aPEO) and UiO-66-NH2 enabling strong hydrogen bonds between the two matrices. Increasing the UiO-66-NH2 loading unexpectedly decreases CO2 permeability in freestanding films, but it surprisingly leads to the best CO2/N2 separation properties in the membranes at a loading of 10 mass% (CO2 permeance of 2900 GPU and CO2/N2 selectivity of 48). Nanoconfinement significantly influences the morphological and gas separation properties of the MMM layer. The membrane with 10 mass% UiO-66-NH2 demonstrates mixed-gas CO2 permeance of 1400 GPU and CO2/N2 selectivity of 76 in the presence of 1.2 mol% water vapor at ≈23 °C, surpassing Robeson's upper bound. The membrane also demonstrates stable CO2/N2 separation performance when challenged with real flue gas for 700 h continuously.  相似文献   
35.
    
Recent technological developments in renewable energy systems and significant growth of solar and wind energy have made these 2 renewable sources potential viable alternatives for conventional energy sources. However, due to intermittent nature, their reliability and availability are not similar to traditional sources. Hence, it is crucial to estimate the solar and wind availability and contribution more accurately. There are various factors affecting the generation capacity of renewable sources. There has been a vast research on the impact of factors related to climate condition such as wind speed, air temperature, and humidity on renewable energy generation. However, there are several other factors with indirect impact on renewable capacity and generation mostly overshadowed by the climate factors. In this study, a multi‐predictor regression model is developed and presented for solar and wind energy generation capacity across the USA. Our study of 50 states shows how the generation capacity can be affected by several indexes including human development index. Variables with the more significant impacts have been chosen using a regression analysis. A recommendation on the best transformation of the response variables and sensitivity analysis of the results has also been presented. The results provide a model to estimate the generation capacity using significant predictors. For instance, the impact of population growth on the wind turbine generation can be explored using these models.  相似文献   
36.
    
Over the last few decades, the significant increase in energy demand followed by increasing fossil fuels depletion convinced countries authority to choose renewable energy to satisfy demand. Therefore, global enthusiasm in renewable energy such as bioenergy technology is increased. Is biofuels technology ready to address the global demand for energy? Investigating in technology development can answer. In this paper, the current statuses of biofuel technologies are determined. Regarding patent codes, seven technologies are identified, which are CHP turbines for biofeed, gas turbine for biofeed, biodiesel, grain bioethanol, bio‐pyrolysis, torrefaction of biomass, and cellulosic bioethanol. The results of patent investigating show that the biodiesel technology is in the mature status and its technology trend is going to go downward. The others six technologies are in the growth stage. Analysis of 57 619 patents in biofuel technologies for technology forecasting has been done by technology life cycle. The torrefication of biomass technology has started its growth stages and will become mature in 2061. In this research, the S‐curves of all biofuel groups are plotted and maturity phases are forecasted.  相似文献   
37.
    
Wettability alteration of carbonate reservoirs from oil-wet to water-wet is an important method to increase the efficiency of oil recovery. Interaction between surfactants and polymers can enhance the effectiveness of surfactants in EOR applications. In this study, the interaction of polyethylene glycol (PEG) with an ionic surfactant, sodium dodecyl sulphate (SDS), is evaluated on an oil-wet carbonate rock surface by using contact angle measurements. The results reveal that wettability alteration of carbonate rocks is achieved through PEG/SDS interaction on the rock surface above a critical aggregation concentration (CAC). The behaviour of PEG/SDS aqueous solutions is evaluated using surface and interfacial tension measurements. Furthermore, the effect of PEG and SDS concentrations and impact of electrolyte addition on PEG/SDS interaction are investigated. It is shown that electrolyte (NaCl) can effectively decrease the CAC values and accordingly initiate the wettability alteration of rocks. Moreover, in a constant SDS concentration, the addition of NaCl leads to a reduction in the contact angle, which can also be obtained by increasing the aging time, temperature and pre-adsorption of PEG on the rock surface.  相似文献   
38.
This study investigated and compared the practical methods used for the efficient Field- Programmable Gate Array (FPGA) implementation of space-time adaptive processing (STAP). The most important part of calculating the STAP weights is the QR decomposition (QRD), which can be implemented using the modified Gram-Schmidt (MGS) algorithm. The results show that the method that uses QRD with less computational burden leads to a more effective implementation. Its structure was parameterised with the vector size to create a trade-off between the hardware and performance factors. For this purpose, QRD-MGS algorithm was first modified to increase the speed, and then the STAP weight vector was calculated. The implementation results show that decreasing the vector size decreases the resource utilisation, computational burden and the consumption power. While the computation time increases slightly, the updated rate of the STAP weights is maintained. For example, the STAP weights in a system with 6 antenna arrays, 10 received pulses and 200 range samples computed in 262 µs using a vector size of 17 on the Arria10 FPGA that has a maximum of 155 µs correlates to the QRD-MGS algorithm and 107 µs correlates to the other parts. Therefore, QRD-MGS algorithm is the most important component of the calculation of the STAP weight vector, and its simplification leads to efficient implementation.  相似文献   
39.
    
The probabilistic risk of arch dam failure under thermal loading is studied. The incorporated uncertainties, which are defined as random variables, are associated with the most affecting structural (material) properties of concrete and thermal loading conditions. Karaj arch dam is selected as case study. The dam is numerically modeled along with its foundation in three-dimensional space; the temperature and thermal stress distribution is investigated during the operating phase. The deterministic thermal finite element analysis of the dam is combined with the structural reliability methods in order to obtain thermal response predictions, and estimate the probability of failure in the risk analysis context. The tensile overstressing failure mode is considered for the reliability analysis. The thermal loading includes ambient air and reservoir temperature variations. The effect of solar radiation is considered by an increase in the ambient temperatures. Three reliability methods are employed: the first-order second-moment method, the first-order reliability method, and the Monte-Carlo simulation with Latin Hypercube sampling. The estimated failure probabilities are discussed and the sensitivity of random variables is investigated. Although most of the studies in this line of research are used only for academic purposes, the results of this investigation can be used for both academic and engineering purposes.  相似文献   
40.
    
Gas release and its dispersion is a major concern in chemical industries. In order to manage and mitigate the risk of gas dispersion and its consequences, it is necessary to predict gas dispersion behavior and its concentration at various locations upon emission. Therefore, models and commercial packages such as Phast and ALOHA have been developed. computational fluid dynamics (CFD) can be a useful tool to simulate gas dispersion in complex areas and conditions. The validation of the models requires the employment of the experimental data from filed and wind tunnel experiments. It appears that the use of the experimental data to validate the CFD method that only includes certain monitor points and not the entire domain can lead to unreliable results for the intended areas of concern. In this work, some of the trials of the Kit Fox field experiment, which provided a wide-range database for gas dispersion, were simulated by CFD. Various scenarios were considered with different mesh sizes, physical conditions, and types of release. The results of the simulations were surveyed in the whole domain. The data matching each scenario was varied by the influence of the dominant displacement force (wind or diffusivity). Furthermore, the statistical parameters suggested for the heavy gas dispersion showed a dependency on the lower band of gas concentration. Therefore, they should be used with precaution. Finally, the results and computation cost of the simulation could be affected by the chosen scenario, the location of the intended points, and the release type.  相似文献   
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