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The aim of this study was to show that abundant and inexpensive plant oils can be biotransformed to increase biological activity (antioxidant, antimicrobial and cytotoxicity) through hydrolysis reaction catalysed by lipases. We tested homemade and commercial lipases through the biotransformation of nine different plant oils in forty different combinations. First, the chemical composition of the samples was investigated. Thereafter, biological tests were conducted to assess the antioxidant and antimicrobial activity of the sampled biotransformation products, as well as analyzed their influence on the viability of healthy and cancer cells. Summarising, sunflower, corn and olive oils modified by orange waste-obtained lipases presented the most promising results, reaching up to 90% of antioxidant activity increase and significant growth inhibition of bacteria colonies belonging to genera Escherichia, Listeria, Staphylococcus, Pseudomonas and Salmonella. In addition, those compounds affected human oral squamous carcinoma cells. The bioconversion of plant oils through lipases improves their biological properties and might be an option for biotechnological application.  相似文献   
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The authors examined whether people can use their knowledge of the wider discourse rapidly enough to anticipate specific upcoming words as a sentence is unfolding. In an event-related brain potential (ERP) experiment, subjects heard Dutch stories that supported the prediction of a specific noun. To probe whether this noun was anticipated at a preceding indefinite article, stories were continued with a gender-marked adjective whose suffix mismatched the upcoming noun's syntactic gender. Prediction-inconsistent adjectives elicited a differential ERP effect, which disappeared in a no-discourse control experiment. Furthermore, in self-paced reading, prediction-inconsistent adjectives slowed readers down before the noun. These findings suggest that people can indeed predict upcoming words in fluent discourse and, moreover, that these predicted words can immediately begin to participate in incremental parsing operations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Penalized solutions to functional regression problems   总被引:1,自引:0,他引:1  
Recent technological advances in continuous biological monitoring and personal exposure assessment have led to the collection of subject-specific functional data. A primary goal in such studies is to assess the relationship between the functional predictors and the functional responses. The historical functional linear model (HFLM) can be used to model such dependencies of the response on the history of the predictor values. An estimation procedure for the regression coefficients that uses a variety of regularization techniques is proposed. An approximation of the regression surface relating the predictor to the outcome by a finite-dimensional basis expansion is used, followed by penalization of the coefficients of the neighboring basis functions by restricting the size of the coefficient differences to be small. Penalties based on the absolute values of the basis function coefficient differences (corresponding to the LASSO) and the squares of these differences (corresponding to the penalized spline methodology) are studied. The fits are compared using an extension of the Akaike Information Criterion that combines the error variance estimate, degrees of freedom of the fit and the norm of the basis function coefficients. The performance of the proposed methods is evaluated via simulations. The LASSO penalty applied to the linearly transformed coefficients yields sparser representations of the estimated regression surface, while the quadratic penalty provides solutions with the smallest L2-norm of the basis function coefficients. Finally, the new estimation procedure is applied to the analysis of the effects of occupational particulate matter (PM) exposure on heart rate variability (HRV) in a cohort of boilermaker workers. Results suggest that the strongest association between PM exposure and HRV in these workers occurs as a result of point exposures to the increased levels of PM corresponding to smoking breaks.  相似文献   
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This paper presents the first attempt to fuse two different kinds of behavioral biometrics: mouse dynamics and eye movement biometrics. Mouse dynamics were collected without any special equipment, while an affordable The Eye Tribe eye tracker was used to gather eye movement data at a frequency of 30 Hz, which is also potentially possible using a common web camera. We showed that a fusion of these techniques is quite natural and it is easy to prepare an experiment that collects both traits simultaneously. Moreover, the fusion of information from both signals gave 6.8 % equal error rate and 92.9 % accuracy for relatively short registration time (20 s on average). Achieving such results were possible using dissimilarity matrices based on dynamic time warping distance.  相似文献   
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Lacking substantial erosive and sedimentation forces, regulated rivers allow their floodplains to become overgrown with forest, increasing the flood risk of the hinterland. In the Netherlands, floodplains have therefore been subjected to interventions, like clear cutting, lowering and creation of side channels, and management, consisting of grazing and mowing. However, the comprehension of how those activities influence landcover dynamics is lacking. The aim of this study is therefore to investigate long‐term landcover dynamics of a regulated river system through the lens of remote sensing. What transitions between landcover classes can be observed? And how (if) do management and interventions impact succession and retrogression of landcover classes? The study area comprised the upstream part of the Dutch Rhine River, its three branches and five adjacent floodplains. Satellite data (LandSat 5 and 8), encompassing a 35‐year period (1984–2018), were used for studying landcover dynamics. Landcover classification was based on seven classes: water, built‐up area, bare substrate, grass, herbaceous vegetation, shrubs and forest. Retrogression was highest for the landcover classes obstructing water flow (shrubs, forest and herbaceous vegetation), succession was most frequent on bare substrate, and water and grass were the most stable landcover classes. The regulated nature of the system became apparent from the spatial and temporal cacophony of landcover dynamics which differ from those of natural meandering rivers. This study showed that satellite data are useful for analyzing the impact of human activities within floodplains of regulated rivers and may assist in floodplain management aimed at combining water safety and nature policies.  相似文献   
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Drying and cooling are preparatory operations typically applied in the soybean processing industry to reduce the moisture content and temperature of the flakes fed to the extractor. Although these parameters are important for a safe and optimal process of extraction, limited or even inexistent schemes for their control are available. To deal with this problem, the current investigation suggests the use of a PID controller to manipulate the speed of the conveyor belt in order to keep the temperature of the flakes in the discharge of the dryer–cooler close to 61 °C without exceeding the acceptable outlet moisture content range from 9.9 to 12.3 % dry basis (d.b.). Closed-loop responses for the controlled variables when considering simultaneous arbitrary disturbances on operating conditions confirmed the reliability of the current control strategy. A dynamic model represented by a system of two partial differential equations obtained by energy and mass balances for the solute in the bed was used as a virtual conveyor-belt dryer-cooler. Its consistency was checked by a comparison between experimental and calculated results for moisture content and temperature at the exit of a size-scale dryer–cooler of soybean flakes at typical industrial operating conditions. The ISE technique and the simplex method of optimization were used to tune the set of PID parameters in which process control was stable.  相似文献   
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The main aim of this study was to investigate the kinetics of solid–liquid extraction of soluble matter from leaves of Ilex paraguariensis assisted by pulsed hydrostatic pressure. A large set of experiments was carried out involving a mixture of distilled water and comminute leaves of mate fed in a batch extractor kept at approximately 16.7 °C. The influence of pressure on equilibrium solute concentrations and rate of extraction was examined in the pressure range from 91.4 to 338.2 kPa by applying or not hydrostatic pressure cycles. Whatever the case a significant increase of such responses with direct positive impact on extraction yield and time of extraction was experimentally observed by changing the investigated factor (e.g.; the extraction yield was increased from ≈13% at 91.4 kPa to approximately 34% and the time to have 90% of the highest efficiency was reduced from ≈17,000 s at 91.4 kPa to ≈6000 s by applying hydrostatic pressure pulses at only 338.2 kPa). An hybrid diffusive–convective model was suggested to represent the transient extraction of soluble compounds from the discoid particles. The classical Fick’s law described the two-dimensional diffusion for the static long periods of mass transfer at constant pressure, while a model dependent on the gamma function computed the fraction of solute periodically extracted by convection from the internal solid microchannels during the rapid pulses of hydrostatic decompression. For all the investigated conditions the proposed analytical model well reproduced the kinetic experimental results of solute mass fraction in the solid and liquid phase.  相似文献   
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