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11.
Six essential oils (EOs), Juniperus phoenicea (leaves and berries), Thymus capitatus, Lauris nobilis, Melaleuca armillaris, and Eucalyptus gracilis, were screened for their antioxidant and antihypertensive activity as well as their chemical compositions. We identified and quantified 24 compounds (representing 99.8% of total oil) for J. phoenicea leaves, 14 compounds (representing 98.8% of total oil) for J. phoenicea berries, 11 compounds (representing 99.6% of total oil) for T. capitatus, 32 compounds (representing 98.9% of total oil) for L. nobilis, 32 compounds (representing 98.7% of total oil) for M. armillaris, and 26 compounds (representing 99.3% of total oil) for E. gracilis. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, the antioxidant activity was in the range of 0.59 to 2183.6 mg/L, whereas T. capitatus (1.24 ± 0.05 mg/L) gave the best activity in the 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonate assay. Antihypertensive activity was evaluated by testing the vasorelaxing capacity of EOs on rat aorta precontracted by phenylephrine (10(-6) M). T. capitatus and L. nobilis were most active for an antihypertensive activity (29 ± 3 and 59 ± 2 mg/L, respectively). Correlations between chemical composition or antioxidant activity and/or antihypertensive activity were studied. Significant correlation has been found for antihypertensive activity and p-cymene (R(2) = 0.86), β-elemene (R(2) = 0.90), and β-myrcene (R(2) = 0.76). A good correlation has been found between antihypertensive activity and antioxidant activity by DPPH assay (R(2) = 0.98). Antioxidant activity can contribute to the prevention of the increase of the blood pressure. According to the literature, no study has been reported until now of correlation between antihypertensive activity and antioxidant activity. Natural EOs can find its interest and application in a medicinal area.  相似文献   
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Activated carbon was used as an adsorbent for the removal of phenol from aqueous solution under various operating conditions. Statistical design using MATLAB® tools was employed to study the effects of three variables on six different response factors. MATLAB® software was employed to solve proposed quadratic model equations and for fitting a quadratic response surface. All the models with a very high adjusted R‐square predicted the experimental data well. The Thomas, the Yoon‐Nelson, the Wolborska, the bed depth service time, and the linear driving force models were used to predict breakthrough curves for experimental data. The results showed that the linear driving force model was suitable for the prediction of the breakthrough curve data.  相似文献   
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Yoghurt was prepared by adding three concentrations of fennel essential oil (FEO) (2.5, 5 and 7.5 µL) in 100 mL of pasteurised milk. Fennel essential oil did not affect the viability of yoghurt starters during fermentation. Based on sensory analysis, only the 5‐µL FEO concentration was incorporated in order to investigate the physicochemical and microbiological properties of enriched yoghurt during storage. Results showed that FEO in yoghurt did not significantly affect the quality after acidification (> 0.05). However, total solid content, syneresis and lightness (L*) differed significantly (P < 0.05). Bacterial counts indicated that the control yoghurt had the highest values. Fortified yoghurt had an increased shelf life of 29 days.  相似文献   
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Filter Bank Multi-carrier Modulations with Offset Quadrature Amplitude Modulations (FBMC/OQAM) is an appropriate alternative to Orthogonal Frequency Division Multiplexing (OFDM) for the fifth generation radio access technology. Being a multi-carrier modulation scheme (MCM), FBMC/OQAM suffers from high Peak to Average Power Ratio (PAPR) and thus exhibits significant distortion in the presence of a non-linear high power amplifier (HPA). To date, no research has considered the idea of combining both linearization and PAPR reduction approaches for the FBMC/OQAM system to cope with this problem. In this paper we jointly used the Tone Reservation (TR) PAPR reduction scheme and the Neural Networks Predistortion (NNPD) as a linearization scheme for both the FBMC/OQAM and the OFDM systems. We suggest a serial combination of the TR and the NNPD schemes. Numerical results showed that the proposed combination of the TR and the NNPD schemes provided better performances than when used separately for both OFDM and FBMC/OQAM systems.  相似文献   
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Exemplar-based inpainting methods involve three critical steps: finding the patch processing order, searching for best matching patches, and estimating the unknown pixels from the best matching patches. The paper addresses each step and first introduces a new patch priority term taking into account the presence of edges in the patch to be filled-in. The paper then presents a method using linear regression based local learning of subspace mapping functions to enhance the search for the nearest neighbors (K-NN) to the input patch in the particular case of inpainting. Several neighbor embedding (NE) methods are then considered for estimating the unknown pixels. The performances of the resulting inpainting algorithms are assessed in two application contexts: object removal and loss concealment. In the loss concealment application, the ground truth is known, hence objective measures (e.g., PSNR) can be used to assess the performances of the different methods. The inpainting results are compared against those obtained with various state-of-the-art solutions for both application contexts.  相似文献   
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Six Tunisian durum wheat genotypes (4 landraces and 2 improved) were evaluated for protein content, gluten strength, rheological characteristics, and HMW-GS patterns using a LabChip system. Variance analysis identified genotypic variation. The landraces Azizi, Mahmoudi, Chili, and Arbi exhibited the highest protein concentrations and gluten contents, and best dough tenacity and extensibility values. The Mahmoudi and Chili varieties had the highest protein contents (17.06 and 17.32% dry mass, respectively). Arbi and Chili had the highest gluten contents (60.88 and 60.59%, respectively). Azizi, Mahmoudi, and Chili were characterized by higher dough tenacity, lower dough extensibility, and a greater alveograph configuration ratio P/L. The high molecular weight glutenin subunits 6+8 (Azizi and Mahmoudi) and 7+15 (Chili), coded by the Glu-B1 locus, improved gluten strength and viscoelastic dough properties. Calculated HMW to LMW-GS ratios were within a narrow range of 0.17–0.29. Some genotypes have potential to be used as parents in breeding programs.  相似文献   
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This document investigates the causal relationship between nuclear energy (NE), pollutant emissions (CO2 emissions), gross domestic product (GDP) and renewable energy (RE) using dynamic panel data models for a global panel consisting of 18 countries (developed and developing) covering the 1990–2013 period. Our results indicate that there is a co-integration between variables. The unit root test suggests that all the variables are stationary in first differences. The paper further examines the link using the Granger causality analysis of vector error correction model, which indicates a unidirectional relationship running from GDP per capita to pollutant emissions for the developed and developing countries. However, there is a unidirectional causality from GDP per capita to RE in the short and long run. This finding confirms the conservation hypothesis. Similarly, there is no causality between NE and GDP per capita.  相似文献   
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Ontological analysis of modelling languages has been mainly used for evaluating quality of modelling language w.r.t. one specific upper ontology. Generally speaking this evaluation has been done by identifying the coverage of the modelling language constructs w.r.t. the ontology and vice-versa. However, a quite limited support has been developed for performing the ontological analysis task. Specifically, various ontologies used for ontological analysis are not associated to a machine readable format; the coverage of modelling language constructs is mostly provided by informal tables mapping one construct on to one ontological concept; the way in which this coverage task is undertaken is poorly specified (resulting in distinct results for distinct experts involved), and finally, preventing any ontology enrichment for dealing with some specialised language constructs. This limited support also prevents application of ontological analysis outcomes to problems and domains dealing with interoperability, integration and integrated usage of enterprise and IS models, which is today one of the key aspects for making interoperable, maintainable and evolvable inter and intra enterprise software systems. The paper provides an overview of the Unified Enterprise Modelling Language (UEML) approach, which introduces advanced support to ontological analysis of modelling languages. The paper is specifically focused on the task of ontological analysis of modelling languages (named incorporation of modelling languages) by introducing and explaining several guidelines and rules for driving the task: therefore, not all the aspects of the UEML approach will be discussed through the paper. The guidelines and rules are illustrated by incorporation of three selected modelling constructs from IDEF3, a well known language for specifying enterprise processes.  相似文献   
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