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21.
Linseed cake (LC), a byproduct of linseed oil extraction, is used as a functional filler for production of biodegradable composites. To determine the influence of residual linseed crude oil contained in lignocellulosic filler on the properties of the poly(lactic acid) (PLA)-based composites with 5–30% filler content, two types of LC were analyzed: a defatted and an unmodified one. Complex analysis of the composites' properties change was conducted in relation to their structure modification caused by the addition of a waste filler. It was found that the addition of LC resulted in simultaneous plasticization and improved crystallization of PLA. Lignocellulosic particles and crude linseed oil contained in the LC powder provided a modifying effect, influencing the level of crystallinity and mechanical and thermomechanical properties. Using LC may thus overcome one of the main drawbacks of PLA, which is brittleness and low crystallinity. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47152. 相似文献
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针对多目标绿色柔性作业车间调度问题(MGFJSP)的特点,提出从碳排放量、噪声和废弃物这3个指标来综合评定环境污染程度,建立了以最小化最大完成时间和环境污染程度为优化目标的MGFJSP模型,并提出了一种改进的人工蜂群算法来求解该模型。算法的具体改进包括:设计了一种三维向量的编码和对应解码方案,在跟随蜂搜索阶段引入一种有效的动态邻域搜索操作来提高算法的局部搜索能力,在侦查蜂阶段提出产生新食物源的策略用于增加种群的多样性。最后进行了实验研究与算法对比,以验证所建模型和所提算法的有效性。 相似文献
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Yifan Deng Bruno Faivre Dr. Olivier Back Dr. Murielle Lombard Dr. Ludovic Pecqueur Prof. Dr. Marc Fontecave 《Chembiochem : a European journal of chemical biology》2020,21(1-2):163-170
The hydroxylation of phenols into polyphenols, which are valuable chemicals and pharmaceutical products, is a challenging reaction. The search for green synthetic processes has led to considering microorganisms and pure hydroxylases as catalysts for phenol hydroxylation. Herein, we report the structural and functional characterization of the flavin adenine dinucleotide (FAD)-dependent 4-hydroxyphenylacetate 3-monooxygenase from Escherichia coli, named HpaB. It is shown that this enzyme enjoys a relatively broad substrate specificity, which allows the conversion of a number of non-natural phenolic compounds, such as tyrosol, hydroxymandelic acid, coumaric acid, hydroxybenzoic acid and its methyl ester, and phenol, into the corresponding catechols. The reaction can be performed by using a simple chemical assay based on formate as the electron donor and the organometallic complex [Rh(bpy)Cp*(H2O)]2+ (Cp*: 1,2,3,4,5-pentamethylcyclopentadiene, bpy: 2,2′-bipyridyl) as the catalyst for FAD reduction. The availability of a crystal structure of HpaB in complex with FAD at 1.8 Å resolution opens up the possibility of the rational tuning of the substrate specificity and activity of this interesting class of phenol hydroxylases. 相似文献
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María D Torres Herminia Domínguez 《International Journal of Food Science & Technology》2020,55(6):2296-2304
Potato processing industry has a high degree of discarding, which currently has low added value being used primarily for animal feed. However, potato wastes offer a broad range of interesting components such as antioxidants, starch, protein or fibre with potential applications in the food and non-food industries. The recovery of these high valuable fractions using efficient multistage and multiproduct processes could be of great interest. This short review provides a general overview on the integral valorisation of potato wastes, offering an updated vision of the main residual parts generated during potato harvesting and processing, the high valuable obtained components focusing on the bioactive ones and the potential of the emerging extraction techniques over conventional ones. In addition, innovative applications are discussed to highlight the scientific and applied interest of these underutilised and undervalued fractions and to emphasise the integral valorisation of raw materials. 相似文献
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Sangeetha Jayakumar T. Nandakumar M. Vadivel C. Thinaharan Rani P. George 《Journal of Adhesion Science and Technology》2020,34(7):713-743
AbstractWe report, here, the corrosion inhibition of mild steel specimen in 1?M HCl by tamarind fruit pulp aqueous (TFPA) extract. The inhibition property in the presence of TFPA extract is studied using weight loss, polarization measurement and electrochemical impedance spectroscopy (EIS). The inhibitor efficiency is found to vary from 74% to 88% (weight loss method) with TFPA concentration of 100–600?ppm. The reduction in Tafel slopes shows that TFPA acts as a mixed-type inhibitor. The adsorption of the inhibitor on the metal surface follows Langmuir isotherm. The standard Gibbs free energy of adsorption value of –40?kJ/mol suggests the chemisorption of inhibitor molecules via coordinate bond. AFM results exhibit a decrease in the surface roughness of mild steel, exposed to 1?M HCl from 299?±?12 to 154?±?6.6?nm, with increasing concentration of inhibitor from 0 to 600?ppm due to the uniform coverage of inhibitor molecules on the metal surface. X-ray photoelectron spectroscopy de-convoluted high resolution profiles of C 1?s (carbon) for mild steel exposed to 1?M HCl with 600?ppm inhibitor show major peaks corresponding to sp3 C–C/C–H (284.9?eV) and oxygen bondings in C–OH, C=O, COOH with a binding energy of 285.9, 286.9, 288.5?eV, respectively, thereby confirming the adsorption of organic moieties on mild steel surface. Fourier transform infrared spectroscopy further confirms the adsorption of inhibitor molecules on the metal surface. Therefore, tamarind fruit pulp extract is a potential corrosion inhibitor for mild steel, which is cost-effective, green and non-toxic. 相似文献
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