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61.
Kenaf (Hibiscus cannabinus L.) is a valuable fiber and medicinal plant from the Malvaceae family. It is an alternative crop that may be a feasible source of cellulose which is economically viable and ecologically friendly. This plant is cultivated for its fiber although its leaves and seeds have also been used in traditional medicine in India and Africa for the treatment of various disease conditions. Kenaf fibers are commonly used for paper pulp and cordage, but it is also a promising lignocellulosic feedstock for bioenergy production. The kenaf seed oil can be used for cooking and in different industrial applications. The present paper is an overview on its ethnobotanical and phytochemical properties reported in the literature that we have investigated and its great potential as a valuable multipurpose crop due to numerous uses.  相似文献   
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In physical vapor deposition on a magnetron cathode, temperature of sensitive components must be kept under threshold limit, so as to ensure the cathode reliability,the process reproducibility, and the best quality of thin films.This can be achieved by an adequate design to enhance the dissipation of heat generated at the cathode. In this paper,temperature distribution and streamlines velocity of the cathode coolant inside a cathode magnetron are analyzed by using CFD solver ANSYS FLUENT in the single-phase method in combination with k–e standards turbulent model.The results show that the design is appropriate under the calculation parameters, and for high heat densities some improvements are necessary to enhance heat dissipation and keep temperature under the threshold limit.  相似文献   
64.
The study focused on characterizing the 10 major Moroccan cultivars to acknowledge the quality and bioactive compounds of the fruits. The following determinations were assessed: pomegranate fruit maturity index, which truly defines juice taste, as well as organic acids and sugar contents, total phenols, and antioxidant activity of pomegranate juice. The cultivar per se (genotype) behaved as the most influencing factor conditioning pomegranate sugar and organic acids profiles, antioxidant activity, and total phenolics. The assessment of pomegranate chemical compositions implies the great potential of Moroccan cultivars for both fresh market and fruit processing. In fact, the "Hamde" sour cv. seems particularly suitable for juice production because of its high phenolics content. Additionally, the presence of bioactive compounds in pomegranate juices may encourage their consumption for potential health benefits. PRACTICAL APPLICATION: The cultivar per se (genotype) behaved as the most influencing factor conditioning pomegranate sugar and organic acids profiles, antioxidant activity, and total phenolics. Given the divergence observed on bioactive compounds concentrations and antioxidant activity among evaluated cultivars, the genotype factor should be considered as the most influencing factor in future breeding programs to enhance the synthesis of beneficial bioactive compounds.  相似文献   
65.
Agricultural wastes such as olive pomace and barley bran have been transformed in plastic by esterification with fatty acid chlorides after acidic or alkaline delignification. These esterifications were carried out in homogenous solution DMA/LiCl by classical heating or microwave activation. The plastics obtained were characterized by IR and NMR spectra, and tested for their mechanical properties and potentiality of biodegradation. The mechanical properties were improved by olefin metathesis of undecylenic ester from olive cellulose. delignification. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 751–755, 2006  相似文献   
66.
The localisation of devices that generate periodically activated hot spots in a CMOS IC comprising five metal layers and metal fills is addressed. The feasibility of using the phase shift of the displacement of the uppermost metal layer due to thermal expansions is demonstrated.  相似文献   
67.
A series of random polyesteramides (PEAs) based on ε‐caprolactone and glycine were synthesized by a direct melt polycondensation method. Their structure was fully characterized by NMR spectroscopy. High molar mass PEAs were obtained for glycine contents lower than 15 mol‐%. The resulting copolymers are semi‐crystalline and present increasing glass transition temperatures but decreasing melting points at increasing glycine contents. Some of these PEAs exhibit better thermal stability and higher Young's modulus and ultimate tensile strength than PCL homopolymer. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40573.  相似文献   
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Rising progress of mm-wave technology in spectroscopy, remote-sensing and its prospective application in communications requires accurate radiation beam characterization in quasi-optical systems. Gaussian approximation is a well-known practical model at optical and infrared wavelengths, and here we try to show the performance and limits of this method for the horn antenna as a classical mm-wave radiation source. This approach provides a compact and more practical analytical tool to design and optimize quasi-optical systems, compared to electromagnetic (EM) full-wave solutions. The radiation pattern (beam shape) and the phase distribution are studied analytically, both with the EM full-wave method and Gaussian approximation. Comparative results with measurements are presented to verify the analytical process and show the feasibility of the method for conventional horns.  相似文献   
70.
We propose in this paper a new backside imaging technique. Due to the constant increase ofnumerous metal layers, active areas can no longer be characterized through the frontside component. Nowadays, the most advanced imaging and failure analysis techniques require a modified backside component to allow probing. We propose a technique, where sample preparations are minimized. An optical time gating is used to reduce artefacts coming from the backside surface.  相似文献   
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