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91.
Oil Content and Fatty Acids Composition in Brassica Species   总被引:1,自引:0,他引:1  
Seeds of 20 accessions of six Brassica species including cultivated and five wild relatives were analyzed for oil and fatty acid composition. The results showed that oil content varied from 21 (B. nigra) to 46% (B. napus). Among wild species, B. rapa and B. oleracea had highest oil content (31 and 28%, respectively). The main fatty acids of oleic, linoleic, linolenic, erucic, palmitic, and stearic acids accounted for 89–94% of the total fatty acids in all species. Cultivated species of B. napus had highest oleic acid (61%) and lowest erucic acid (1%) content compared to other studied species. Brassica rapa and B. oleracea had the highest content of erucic acid (41 and 46%, respectively). The highest content of linolenic (20%) and linoleic (19%) acid was observed for B. juncea. The results showed that there was high genetic variation among the studied species for oil content and fatty acids composition. This indicates that seed oil of these species is possibly suitable for both human consumption and industrial purposes.  相似文献   
92.
93.
Renewable energy resources play a very important rule these days to assist the conventional energy systems for doing its function in the UAE due to high greenhouse gas (GHG) emissions and energy demand. In this paper, the analysis and performance of integrated standalone hybrid solar PV, fuel cell and diesel generator power system with battery energy storage system (BESS) or supercapacitor energy storage system (SCESS) in Khorfakkan city, Sharjah were presented. HOMER Pro software was used to model and simulate the hybrid energy system (HES) based on the daily energy consumption for Khorfakkan city. The simulation results show that using SCESS as an energy storage system will help the performance of HES based on the Levelized cost of energy (LCOE) and greenhouse gas (GHG) emissions. The HES with SCESS has renewable fraction (68.1%) and 0.346 $/kWh LCOE. The HES meets the annual AC primary load of the city (13.6 GWh) with negligible electricity excess and with an unmet electrical load of 1.38%. The reduction in GHG emissions for HES with SCESS was 83.2%, equivalent to saving 814,428 gallons of diesel.  相似文献   
94.
Microbial fuel cell (MFC) is a promising technology for simultaneous wastewater treatment and energy harvesting. The properties of the anode material play a critical role in the performance of the MFC. In this study, graphene oxide was prepared by a modified hummer's method. A thin layer of graphene oxide was incorporated on the carbon brush using an electrophoretic technique. The deoxygenated graphene oxide formed on the surface of the carbon brush (RGO-CB) was investigated as a bio-anode in MFC operated with real wastewater. The performance of the MFC using the RGO-CB was compared with that using plain carbon brush anode (PCB). Results showed that electrophoretic deposition of graphene oxide on the surface of carbon brush significantly enhanced the performance of the MFC, where the power density increased more than 10 times (from 33 mWm?2 to 381 mWm?2). Although the COD removal was nearly similar for the two MFCs, i.e., with PCB and RGO-CB; the columbic efficiency significantly increased in the case of RGO-CB anode. The improved performance in the case of the modified electrode was related to the role of the graphene in improving the electron transfer from the microorganism to the anode surface, as confirmed from the electrochemical impedance spectroscopy measurements.  相似文献   
95.
96.
A facile route for the synthesis of high-quality Fe3O4 nanoparticles (FNPs) has been successfully confirmed by employing a co-precipitation technique and then was stabilized onto wool fabric through a simple “impregnating” process. Here, the synergistic effect of BTCA and synthesized FNPs on magnetic and antifungal characteristics of the wool fabric was investigated. The FNPs was stabilized on the wool surface using BTCA cross-linking agent. The role of both FNPs and BTCA concentrations on magnetic and antifungal properties of samples was optimized using response surface methodology. The magnetization properties and uniform distribution of FNPs on the wool surface were characterized by vibrating sample magnetometry, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The saturation magnetization and antifungal activity against Candida albicans of BTCA/FNPs-optimized wool was 7.8 emu g?1 and 98.31%, respectively. Subsequently, treated wool fabric with optimum concentration of FNPs and BTCA enhanced magnetic and antifungal properties.  相似文献   
97.
Evaluation of membrane clarification of pomegranate juice showed that a cake layer is created at the beginning of the process. This evaluation was used as the basis for modelling the solute concentration in the concentration polarisation layer to control the fouling of the membrane. The model of changes in concentration as a function of time and distance (in its dimensionless form) was solved numerically using the Forward‐Time/Central‐Space (FTCS) method. Programming was performed using MATLAB software, and the predicted concentration on the membrane surface was compared with experimental data; the prediction fit well with the experimental data. The model showed that the solute concentration increased as distance to the membrane surface decreased, time increased, transmembrane pressure increased and velocity decreased. Also, the model matched the experimental data in that it showed the cake layer to be created in the early stages of the membrane clarification process.  相似文献   
98.
In recent years, due to the increasing consciousness of quality in the food and health sector, much progress has been made in developing non-invasive techniques for the evaluation or inspection of internal qualitative parameters of fruits, vegetables, and processed foodstuffs considering, e.g., moisture content, soluble solid content, acidity, and mechanical properties. This paper reviews the theoretical and technical principles as well as the recent achievements and applications of light backscattering imaging for nondestructive evaluation of food and agricultural produce. The results suggest the potential use of this emerging technique in the food industry. Further attempts are pointed out to improve its performance through utilizing advanced image processing coupled with artificial intelligence techniques.  相似文献   
99.
The monitoring of synthetic dyes in foods is very important due to their potential harmfulness to human beings. Herein, a carbon-paste electrode (CPE) that is chemically modified with gold nanoparticles (nAu) was fabricated and used for the determination of Sunset yellow (SY) and Tartrazine (Tz). Cyclic and differential pulse voltammetry (CV and DPV) results revealed two well-resolved anodic peaks for SY and Tz with remarkably increase in oxidation signals of these colourants. Based on this, a novel electrochemical method was developed for the simultaneous determination of SY and Tz. High sensitivity and selectivity, sub-micromolar detection limit, high reproducibility and regeneration of the electrode surface by simple polishing make the nAu-CPE electrode very suitable for the determination of SY and Tz in commercially available soft drinks. The detection limits was 3.0 × 10−8 and 2.0 × 10−9 mol l−1 for SY and Tz, respectively, which are remarkably lower than those reported previously for SY and Tz using other modified electrodes.  相似文献   
100.
The present work deals with the numerical and experimental analyses to study the detailed behavior of the thermally induced flow of water in an open vertical annulus, circulating through a cold leg forming a closed loop thermo-siphon. Spatio-temporal behavior of fluid flow is also studied for variety of heat fluxes. The annuli in the present study have a radius ratio of 1.184 and aspect ratio (length to annular gap) equal to 352. The objective of the present work is to quantify the effect of heating on design parameters such as liquid and wall temperatures, mass flow rate, and heat transfer coefficient. Experiments have also been conducted on a similar system with water at constant heat flux of 1 kW/m2, 2.5 kW/m2, 5 kW/m2, 7.5 kW/m2, 10 kW/m2, 12.5 kW/m2 and 15 kW/m2. For numerical purpose, a two-dimentional solver has been developed for direct numerical simulation of the essential thermally induced flow dynamics The numerical solution was thus performed for Rayleigh numbers ranging between, 4.4 × 103 and 6.61 × 104 which correspond to the given heat flux, respectively.  相似文献   
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