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关键词： Vegetable fibers   Polypropylene fiber   Physical properties   Mechanical properties   High temperatures   Microstructure  

摘要： Sustainable development today requires smart deployment of renewable environmentally-friendly materials and innovative thoughts. It is unavoidable to assess their performance and engineering properties to be accepted by the civil engineering community. Thus, vegetable fibers as reinforcement for cementitious materials are a very interesting eco-option for the construction industry. This paper study the behavior of metakaolin cementitious mortars reinforced with vegetable (VF)/polypropylene (PP) fibers under high temperature exposure. Vegetable fibers were previously treated with calcium hydroxide in order to improve their paste-adhesion and durability. Four VF mortars (including Alfa mortar (MAF), Diss mortar (MDS), Date Palm mortar (MDP), Hemp mortar (MHE)), one PP mortar (MPP) and one control mortar (CM) were made. The mixes had a sand/binder ratio of 3, 30% matakaolin content, and 0.1%/m(3) fibers dosage. The induced firing-changes were studied at room temperature (20 degrees C) and after heating process at 150, 300, 450, and 600 degrees C. The tested properties were: residual mechanical strengths, ultrasonic velocity, thermal conductivity, porosity, density, thermogravemetric analysis, and optical and microstructural observations. The results showed a similar behavior of vegetable and polypropylene fibers' mortars under fire with a different mechanism;a diminished spalling with fibred mortars;Ca(OH)(2) treatment and metakaolin rich matrix was a good prescription to get enhanced VF-mortars properties. (C) 2021 Elsevier Ltd. All rights reserved.

关键词： PET-poly(terephtalate ethylene)   Fly ash   Composite lightweight aggregate   Portland cement   Circular economy   Eco-composite  

摘要： This article presents testings' results of cement composites with Composite Lightweight Aggregates (CLAs) as a partial substitute of natural aggregates. A new sustainable eco-composite manufacturing took place in laboratory conditions by using 100% waste by-products: PET flakes and sewage sludge fly ash (ssFA) streams or siliceous fly ash (FA). The manufactured (EN 196-1) modified cement mortars were tested in a various series of CLAs by applying volume replacements of 10% and 25% regarding the standard aggregate. The new insights on physical-chemical properties of the original materials and effective water and mechanical performance of both the fresh and hardened specimens contrasted the qualitative and quantitative assessments in the function of the two different aggregates production methods lines. Frattini test is also used to assess the impact of the aggregate composite on the cement composite and their mutual interactions. The obtained results show that the use of CLA as a substitute of standard aggregate allows reducing the water content in the mix while maintaining good workability and increasing compressive and flexural strengths up to 25% of reference mortar. (c) 2020 Elsevier Ltd. All rights reserved.

关键词： edible film   navy bean starch   corn starch   physicochemical properties  

摘要： BACKGROUND Recently, there has been a great interest in developing new applications of edible dry beans (Phaseolus vulgarisL.). The utilization of starch, comprising the major component of dry bean seeds, for the preparation of edible films has just emerged. RESULTS In the present study, we chose navy bean as a model dry bean source, isolated its starch component, prepared edible films with different formulations (35 and 40 g L-1), and compared these with the films made using isolated and commercial corn starches. Sunflower oil at 10 g L(-1)was dispersed into film-forming solution to design composite films. The water vapor barrier property, mechanical properties and microstructure of starch films from navy bean and corn were studied to evaluate their potential for use in food packaging. All of the films had smooth and uniform surface and were transparent. CONCLUSION Navy bean starch film showed physicochemical and mechanical properties comparable to corn starch films, and the addition of sunflower oil could further improve the water vapor barrier and mechanical properties of films. The findings obtained in the present study demonstrate the potential of using navy bean starch to prepare edible films. (c) 2020 Society of Chemical Industry

关键词： Melanoidin (MLD)   Black garlic   Physicochemical properties   Antioxidant activities   Simulated digestion  

摘要： As the important compounds in black garlic, the physicochemical properties and bioactivities of melanoidin (MLD) were investigated in this study. The results showed that MLD possessed strong metal-ion chelating capacity and radical scavenging activities which were positively correlative with molecular weight (MW). During the simulated digestion in vitro, the ultraviolet absorption, browning degree and MW distribution of MLD remained the same as initial. It proved that the MLD from black garlic could be indigestible like the dietary fiber with little loss of volatile compounds and polysaccharides. Remarkably, the bioactivities of MLD were reduced significantly under the treatment of alpha-amylase or hydrochloric acid, while they were stable and retained over 60% after adding pepsin and pancreatin. This study provides fundamental evidences for further research and widely application of MLD and black garlic in the production of functional food or food additives.

关键词： Soybean roasting   Beany flavor   Lipoxygenase   Peroxidase   Volatile compounds   Electronic nose   HS-SPME-GC-MS  

摘要： We applied oven-roasting on soybean in order to investigate their physicochemical, sensory, and volatile profiles using electronic nose and HS-SPME-GC-MS. Results revealed a temperature dependent kinetic on the physicochemical index except fat content. Roasting at 200 degrees C for 20 min decreased the protein dispersibility index about 38%;while, lipoxygenase and peroxidase were entirely inactivated. The primary heat sensitive amino acids were methionine, arginine, and cysteine. Electronic nose showed certain capacity to discriminate varying roasted soybeans. Out of 41 volatile compounds identified in soybean headspace, 2,5-dimethylpyrazine showed the highest abundance of 411.18 mu g/Kg. Regression model suggested the association of hexanal and aliphatic alcohols with beany flavor, while pyrazines, heterocycles, and furanoids showed a positive correlation with roasted flavor. The selected flavor markers can be used to predict the development of flavor in roasted soybeans. Our study emphasized the effect of roasting level on nutritive value and flavor profiles of soybeans.

关键词： Phenolic compounds   Antioxidants   Antimicrobial activity   Emulsion gels   Physico-chemical properties   Lipid structure  

摘要： This article evaluates the use of emulsion gels (EGs) containing two different solid polyphenol extracts [from grape seed (R-EPG) or grape seed and olive (R-EPGO)] as animal fat replacers in the development of frankfurters. The incorporation of EGs improved their lipid content, particularly R-EPG and R-EPGO also contained high levels of phenolic compounds (hydroxytyrosol and flavanols). These frankfurters were judged acceptable by the panellists and showed good thermal and storage stability. Colour parameters, pH and textural properties were affected (p < 0.05) by the formulation, being significant the influence of polyphenols extracts. Spectroscopic results showed greater (p < 0.05) interand intramolecular lipid disorder in the frankfurters with EGs, irrespective of the presence of polyphenol extracts. Comparing the reduced-fat samples, R-EPG and R-EPGO showed the lowest (p < 0.05) total viable counts. Significant changes in pH and texture parameters were observed during chilled storage while lipid structure was not affected.

关键词： Lanthanide oxide   Functionalization   Physicochemistry   Superhydrophobicity   Petal and lotus effect  

摘要： According to the developed bioinspired method in the one-step procedure, the material with the petal effect was switched to lotus one. Therefore, highly hydrophobic and super-hydrophobic materials with tunable adhesive properties and fractal-like structures were successfully produced with high efficiency (67-84%). The work's essence was to modify chemically selected powders of lanthanide oxides (CeO2, Pr6O11, Nd2O3, and Gd2O3). High effectiveness of the functionalization process with 1H,1H,2H,2H-perfluorooctyltriethoxysilane (FC6) and n-octyltriethoxysilane (C6) was proven by various techniques, e.g. XPS, HR-TEM, ATR, XRD, zeta potential. Materials with water contact angle between 143.6 degrees (CeO2-C6) and 175.5 degrees (Nd2O3-FC6) with thermally stable nanolayer (up to 380 degrees C) were generated. Surfaces functionalized with FC6 possessed a polar component of surface free energy (SFE) close to zero. Water behavior in contact with the modified materials was studied, taking into consideration the unique electron structure of lanthanides assessed by goniometric measurement, also adhesion and spreading pressure were determined. Very low adhesion and polar SFE partly resulted in immediate bouncing of water droplet upon contact with the modified surface. The presented method allows preparing stable materials with a high potential in materials chemistry and modulation of surface features and engineering (e.g. heat transfer fluids, specific coating).

关键词： Metal nanoparticles   Metals   Gold   Metal clusters   Chemical synthesis