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关键词： Yogurt supplementation   Green tea polyphenols   Protein particles   Bioaccesibility  

摘要： Purpose The purpose of this paper is to evaluate the effect of green tea polyphenols addition on physicochemical, microbiological and bioactive characteristics of yogurt. Design/methodology/approach Two incorporation methods of polyphenols were evaluated: direct addition or incorporated within protein particles of whey protein concentrate and gelatin. During yogurt's shelf life, structure characteristics (water holding capacity, textural and rheological parameters), lactic acid bacteria (LAB) viability and polyphenols antioxidant activity were analyzed. Also, polyphenol bioaccesibility after in vitro digestion was evaluated. Findings Polyphenols addition (by the two methods used) did not affect the dynamics of the fermentation process, nor the LAB viability during storage. The color parameter a* for the yogurts with the highest polyphenol concentrations showed positive values (tending to red), but not visible to the naked eye. Because of the ability of polyphenols to interact with milk proteins, yogurts with polyphenols presented higher values in firmness and cohesiveness with respect to the control. Additionally, the incorporation of polyphenols in protein particles increased even more these parameters because of the higher protein content of these formulations. After simulated digestion, a high polyphenol bioaccesibility was observed, and the antioxidant activity was retained, which could be explained by the "protector" effect of the milk matrix. Practical implications Yogurt supplementation with green tea polyphenols is feasible for the development of functional food. However, the use of protein particles would not provide an extra benefit because milk proteins already act as protective molecules of polyphenols. Originality/value This study shows not only the physico-chemical implications of including polyphenols in yogurt but also their bioaccesibility after an in vitro digestion, revealing a suitable manner for delivery of antioxidants in a dairy product like y

摘要： The influence of the surface finishing of breast implants on physicochemical and mechanical properties, before and after extreme degradation experiments, was investigated in this study. Removal of superficial layers after degradation was verified for both smooth and rough membranes, in which local erosion was verified. FTIR results demonstrated the generation of low-molecular-weight structures in all samples due to exposure to acidic and basic environments. Furthermore, smooth samples presented higher degrees of crosslinking than rough samples. Considering the mechanical properties, no difference was verified between smooth and rough samples as received and after degradation studies. However, the pH of the degradation solution had an influence on mechanical properties of the material and a basic environment caused greater deterioration of the mechanical properties compared to acidic conditions.

关键词： Plant-based milk   Attalea speciosa   Fruit juice   Color   Penalty analysis   Check-all-that-apply  

摘要： Purpose The purpose of this study was to develop plant-based babassu milk flavored with grape fruit (GF). Design/methodology/approach A four mixed beverages formulations containing 15%, 25%, 35% and 45% GF were produced. The pH, titratable acidity (TA), soluble solids (SS), sugar: acid ratio and color analysis were performed. Sensory evaluation was measured by the hedonic scale, just-about-right (JAR) scale and purchase intent. Moreover, a check-all-that-apply (CATA) form was applied to obtain description data on the formulations. Findings The pH values of mixed beverages decreased (p < 0.05) when the concentration of GF increased, while the TA and the SS increased (p < 0.05). The GF addition provided the product with greater opaque and redness. Sensory evaluation revealed good consumer acceptance. For the hedonic scale, 35% and 45% GF contributed to the higher acceptance of color, appearance, flavor and overall liking attributes. For JAR data, the flavor grape term was highest in the JAR region (51%) with 45% GF. Based on the frequency of terms cited by consumers in the CATA test, the treatment with 15% GF was described by babassu flavor, strange and low astringency terms. For purchase intent, most consumers would buy the product with 35% and 45% GF. Originality/value This study demonstrates that babassu, an almond little used industrially, is an alternate to plant-based milk. The higher sensory acceptance occurs when 45% GF is used for its flavoring. The CATA indicated that ideal sweetness, striking, acid and ideal grape flavor described the better beverage.

关键词： Beef   Colour   Drying   Dried meat   Microwave drying  

摘要： Purpose The aim of this work was to study the effect of the different levels of salt and the temperature on some physico-chemical and colour change properties of microwave-dried beef round (M. semitendinosus). Design/methodology/approach The samples were pretreated with different temperatures (0 degrees C, 40 degrees C and 50 degrees C) and salting (0, 1.5, 2.5%). Later these samples have been dried by the microwave energy at 540 W for seven minutes. Some physical properties (water activity, moisture content, change in diameter, change in thickness, change in shrinkage ratio) and texture, colour and microscopic surface structure analysis were conducted in dried beef round samples. Findings As a result, the colour and moisture were the most affected factors. Also, physical and microstructural characteristics were affected by salting and pre-drying. In addition, while the textural structure did not show a significant difference, meat weight and water activity varied. Research limitations/implications Meat obtained from a local butcher in Konya was used as the study material. In addition, only a special part of the meat (M. semitendinosus) was used in the study. In the drying process, the parameters were determined as 540 W and 7 min. These are the limitations of the research. Originality/value All changes that can occur in the physical properties of the meat after the drying process were examined. The structure of beef round samples formed by microwave drying was shown by using electron microscope. The effects of pretreatment such as salting and pre-drying have been examined on microwave drying.

关键词： MBR   Fouling control   Biological   Physicochemical   Wastewater reclamation  

摘要： Fouling in membrane bioreactors (MBR) is a bottleneck problem limiting their application. In-situ fouling control strategies have been continuously developed for decades, and can be mainly categorized as biological and physicochemical approaches. However, the mechanisms and performance of these methods as well as their application prospects have not been thoroughly discussed and compared in a systematic manner. This study was aimed at providing a detailed review on the various in-situ biological and physicochemical methods in terms of fouling control performance, fouling reduction mechanisms and practicability. This involves a comparison of the popular biological control strategies including quorum quenching (QQ)) and physicochemical approaches such as NaClO backflushing, hybrid electrochemical MBR and anti-biofouling membrane development, with the analysis of their potential, existing issues and practicality in full-scale applications. Future work is also recommended for developing more sustainable and more widely applicable MBR fouling control strategies. (C) 2021 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

关键词： Aging effect   Microscale zero-valent iron   Trichloroethylene (TCE)   Transformation   Removal mechanism  

摘要： Microscale zero-valent iron (mZVI) has been widely used for the in-situ groundwater remediation of various pollutants. However, the aging behavior of injectedmZVI particles limits the widespread application in groundwater remediation projects. To assess the long-term reactivity of mZVI particles, the mechanism of trichloroethylene (TCE) degradation by various aged mZVI particles (A-mZVI) was determined by quantitatively evaluating the contributions of chemical reduction and adsorption. Further, this study investigated the physicochemical transformation of mZVI particles aged under various hydraulic conditions (static and dynamic), redox conditions (anoxic and aerobic) and aging durations (152 d and 455 d). The results showthat the removal of TCE by different A-mZVI particles increased the sorption capacity in the initial period (0-6 h). However, in the long term, a significant inhibition of TCE removalwas observed because of the decreased TCE reduction capacity caused by the hindrance of electron transfer, which was generated by corrosion precipitates. Furthermore, the characterization results demonstrated that despite the significant differences in the apparent morphology of the A-mZVI particles in various groundwater conditions, the final crystal corrosion products were mainly Fe3O4. Thus, the aging and inactivation ofmZVI particles on TCE removalwere promoted under the aerobic conditions. In addition, the structure ofmZVI particles collapsed fromthemicro- to nanoscale under anaerobic dynamic over 455 d. No substantial impact on the final TCE removal was observed for the A-mZVI particles prepared under various hydraulic conditions and aging times. These findings provide insights regarding the impact mechanisms of corrosion precipitates on the removal of target contaminant and provide implications for long-term mZVI application under various target aquifer conditions. (c) 2021 Elsevier B.V. All rights reserved.

摘要： Land degradation in the form of soil erosion and fertility depletion is the major environmental problem in Ethiopia. However, to curb this problem, soil and water conservation (SWC) structures are commonly practiced in many rural parts of Ethiopia. This study was conducted to assess the effects of SWC structures on selected soil physicochemical properties in Ejersa Lafo district. For this study, two kebeles (peasant associations) were selected purposively from the district based on the severity of soil erosion and information on SWC practices. The research design employed in this study was systematic, randomized, complete block design. A total of 12 composite soil samples were collected from the depth of 0 to 20 cm at two subwatersheds, namely, Jamjam laga batu and Koriso Odo guba with SWC and without SWC structures at three landscape positions. All the soil samples were analyzed following the standard and recommended procedures. The effect of independent variables (SWC practices and landscape positions) on the dependent variables (soil properties) was statistically tested using the SPSS computer program 21. In this study, most of the selected soil physicochemical properties were affected by watershed management intervention (SWC) structures. Soil moisture content (SMC), clay, pH, electrical conductivity (EC), total N (TN), available (AP), available K (AK), and organic carbon (OC) were higher in the subwatershed treated with SWC structures (conserved), whereas bulk density, silt, and sand were higher in the subwatershed without SWC structures (nonconserved). Most of the selected soil chemical properties were significantly varied (p<0.05) between conserved and nonconserved farm land except EC. All the selected soil physicochemical properties did not show any significant variation (p<0.05) at landscape positions except sandy soil. The physicochemical soil properties of selected parameters were in good conditions in the conserved areas with higher N and OM and lower BD

关键词： Pre-geopolymers   Geopolymerization kinetics   Mechanosynthesis   Mechanical resistance   Fly ash  

摘要： This work aims to study the feasibility of preparation of geopolymer pastes, from pre-geopolymer powders obtained by mechanosynthesis and water. These geopolymer pastes (MGP) were compared to the conventional geopolymer pastes (CGP) in terms of structural, microstructural and mechanical properties. CGP were manufactured by the mixture of fly ash as precursor with alkaline activator solution. Pre-geopolymer powders (PGP) were prepared by the high-energy milling of a dry mixture of fly ash and alkaline activators, with different Na2SiO3/NaOH mass ratios (2.5, 4 and 8) and milling times of 5, 10 and 15 min. CGP and MGP pastes were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), particle size distribution analysis, compressive strength tests and in situ attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), in order to highlight structural, microstructural and mechanical changes that could occur, and to follow geopolymerization kinetics respectively. The results pointed out that the MGP structures are mainly amorphous, with appearance of zeolitic crystals, depending of the chosen formula and the milling time. The in situ ATR-FTIR analysis indicated that the fly ash characteristic band (1027 cm(-1)) shifts towards lower wavenumbers, with a much larger shift for MGP than for CGP. The compressive strength results showed optimum values of 28 MPa for MGP and 15 MPa for CGP, after 7 curing days at 20 degrees C and 50% of relative humidity. (C) 2021 Elsevier Ltd. All rights reserved.

关键词： Positive ions  

摘要： Ionic liquids (ILs) have been labeled as a promising green alternative to traditional materials;however, many ILs have been discovered to be toxic, especially hydrophobic ILs (HILs). HILs are limited in their structural diversity as most are composed of heteroaromatic cations with long alkyl chains and paired with [BF4], [PF6], or [NTf2] anions. This study aims to diversify HILs by synthesizing two sets of HILs with unique cations and anions. The first set of HILs contain cholinium- and dicholinium-based cations paired with the [NTf2] anion. The [DC-ether] cation is identified as a promising cation and is paired with an array of asymmetric bis(sulfonyl)amide anions to form the second set of HILs. In total, twenty HILs are synthesized. Each HIL is characterized using traditional physicochemical techniques and is evaluted for toxicity using in vitro and in vivo methods.

关键词： Nanomaterials   Sensors   Biocompatibility   Two dimensional materials   Toxicity  

摘要： Graphene family nanomaterials (GFNs) are rapidly emerging for ocular applications due to their outstanding physicochemical properties. Since the eyes are very sensitive organs and the contact between the eyes and GFNs in eye drops, contact lenses, intraocular drug delivery systems and biosensors and even the workers handling these nanomaterials is inevitable, it is necessary to investigate their ocular toxicities and physiological interactions with cells as well as their toxicity mechanisms. The toxicity of GFNs can be extremely affected by their physicochemical properties, including composition, size, surface chemistry, and oxidation level as well as dose and the time of exposure. Up to now, there are several studies on the in vitro and in vivo toxicity of GFNs;however, a comprehensive review on ocular toxicity and applications of GFNs is missing, and a knowledge about the health risks of eye exposure to the GFNs is predominantly unspecified. This review highlights the ocular applications of GFNs and systematically covers the most recent advances of GFNs' physicochemical properties, in vitro and in vivo ocular toxicity, and the possible toxicity mechanisms as well as provides some perspectives on the potential risks of GFNs in material development and biomedical applications.