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181.
The numerical study of laminar forced convection inside double-flow solar air heater with electrohydrodynamic technique is investigated by finite difference method. The electric field is generated by the wire electrodes charged with DC high voltage. The mathematical modeling of computational fluid dynamics includes the interactions among electric field, flow field, and temperature field. It can be perceived that augmented heat transfer with presence of an electric field increases with the supplied voltage but decreases with the total mass flux. The optimized mass flux ratio is expressed incorporating with concerning parameter comprising of the electrode arrangement, the number of electrodes, the total heat flux at an absorbing plate, and the channel geometry.  相似文献   
182.
Dietary fibres and high fibre-containing foods have been a huge attraction among researchers and nutraceutical industries due to their health-promoting benefits. From Greek and Roman times, edible mushrooms are considered the ‘elixir of life’ and are often stated as a new source of dietary fibre. Containing rich sources of essential amino acids and polysaccharides, mushrooms are viewed as an advantage over protein sources of both animal and plant origin. Additionally, the ability of mushrooms to grow under controlled conditions and attain high yield in a short span has made this added-value food of extreme interest. Nowadays, mushrooms and their by-products have been used to fortify various food products as well as for use in animal feed owing to their bioactive, therapeutic and nutritional value. Hence, this review intends to highlight the current knowledge on edible mushrooms and their waste for food and feed enrichment and nutritional purposes, along with their role in human and animal diet.  相似文献   
183.
This work proposes a fluorescent probe based on CdTe quantum dots (QDs) for the determination of resveratrol in wine samples. The synthesis of cysteamine (CA) capped CdTe QD was carried out in a one-pot eco-friendly process, resorting to the electrochemical reduction of metallic tellurium powder in a graphite macroelectrode (cavity cell). The reduced species of tellurium (Te2? and Te22?) migrated to an intermediate compartment of the electrochemical cell and in the presence of a cadmium salt and organic stabilizing agent (CA), forming the colloidal dispersion of CdTe in a single step. Under optimum synthesis conditions, the fluorescence intensity of the prepared nanoparticles varied linearly with the resveratrol concentration in the range from 3.25 to 75 μg L?1 (R2?=?0.9984), with a detection limit of 0.97 μg L?1 and RSD of 3.7% (5.0 μg L?1 resveratrol, n?=?10). The method was successfully applied to the resveratrol determination in wines, with recoveries from 97.8 to 112.4%. Student’s t test was applied and no statistically significant difference was observed between the two methods (HPLC and proposed), with a confidence level of 95% (ttabulated?=?2.45 and tcalculated?=?0.38). The resveratrol determination method, by using CdTe-CA QDs as fluorescence probe, was simple, rapid, inexpensive, and sensitive.  相似文献   
184.
This study compared the effectiveness of fungal chitosan nanocomposite, chitosan gel and chitosan nanoparticles against strawberry phytopathogenic fungi (Botrytis cinerea; Rhizopus stolonifer and Aspergillus niger). Nanoparticles were prepared by ionic gelation method and characterised by dynamic light scattering and scanning electron microscopy. The influence of the edible coatings on fungal growth was analysed in vitro and in vivo The fungal chitosan nanoparticles presented an average size = 331.1 nm (±7.21) with a narrow size distribution (PDI = 0.377) and a zeta potential = +34 mV. The edible coating made by the nanocomposite exhibited important changes in fungal morphology, and the best control of the growth of the assayed fungal strains in artificially infected strawberries. Therefore, nanotechnology brought some benefits to the conventional chitosan gel edible coating, improving its antifungal activity and forming a new eco-friendly coating.  相似文献   
185.
Despite the obvious diversity in the ideology, materiality and character of architectural production, here it is argued that the way we (architects) draw is surprisingly uniform. One reason for this might be the limited range of materials and tools we draw with, and their generic qualities. Architect, researcher and maker Nat Chard reveals relationships between acts of drawing, making images and making ideas, by taking us through the design and manufacture of a series of analytical drawing instruments and contingent works. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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