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关键词： Vitamin K3   Menadione   2-methyl-1,4-naphthoquinone   Abraham descriptors   Solubility   Linear free energy relationships   Partitions  

摘要： We have used literature values for the solubility of vitamin K3 in organic solvents to obtain Abraham descriptors for vitamin K3. Although these descriptors themselves are not exceptional in any way, when combined with equations that we have already set out, they lead to the prediction of important properties of vitamin K3. These include the vapor pressure and heat of sublimation (necessary for the analysis of data on the concentration of vitamin K3 in ambient air), and the partitions air-water, air-blood, air-lung, air-fat, air-skin, water-lipid, water-membrane, water-skin, as well as permeation from water through skin. Values of the partitions into biological phases are all quite large by comparison to those for organic compounds in general. (C) 2021 Elsevier B.V. All rights reserved.

关键词： Dry pea   Pea starch   Supercritical fluid extraction   Thermal properties   Gelatinization behavior   C-type Starch   Degree of double helix   HPSEC   FT-IR   X-ray diffraction  

摘要： The objective of this study was to establish the impacts of supercritical fluid extraction (SFE) processing on the physicochemical properties of pea flour and the structure of isolated pea starch. A significant (p < 0.05) increase in protein content and reduction in several pasting and thermal parameters as measured by rapid visco-analyzer and differential scanning calorimeter were observed after SFE. Additionally, SFE increased starch digestibility as determined by an in vitro starch digestion assay. An increased amylopectin content and crystallinity along with the loss of double helix content was supported by size exclusion chromatography and FT-IR data, respectively. X-ray diffraction and scanning electron microscopy showed minimal alterations of starch, by SFE, in long-range crystalline and morphological structure of starch granules, respectively. The data demonstrated SFE influenced the physicochemical and structural characteristics of pea starch. These outcomes illustrated that SFE might be a green and novel technology for starch modification.

关键词： Biomass feedstocks   Pyrolysis mechanisms   Carbon sequestration   Biochar properties   Agronomic applications  

摘要： The biochar is a solid carbon-rich, porous material produced by the thermochemical conversion of a diverse range of biomass feedstocks under an inert atmosphere (i.e., in the absence of oxygen). We can produce the biochar at all likely scales, ranging from the industrial to the domestic level and even at individual farms, thus, the biochar industry is leading as a most appropriate at different socioeconomic settings. The possibility of sustainable biochar production practices and multi-functionality features make it a promising candidate to fulfill an increasing demand in the fields of soil amendment, agricultural sustainability, environmental protection, cutting-edge materials, and to achieve circular bio-economy and mitigation of climate change. An available fraction of waste biomass (agroforestry waste, biomass crops, agricultural residues, mill residues, and animal manure, and many more) can be used efficiently in pyrolysis and converted into desired biochar materials, besides this alternative energy products, such as syngas, bio-oil, electricity generation, and process heat. This report emphasizes the fate of biomass composition, pyrolysis mechanisms, and applications of modern analytical and characterization techniques that are being adopted, applied, and standardized to improve understandings of molecular, structural, and surface properties characteristics of biochar. To achieve precisely designed biochar, there is a need to understand the latest advances in biochar materialization mechanisms and structure-application relationships to speed up their agronomic applications and to achieve a zero-waste dream. This report also summarizes a wide range of literature published on feedstocks, pyrolysis, and biochar and suggests several practical recommendations appropriate to implement and bring together specific details on the thermochemical conversion of biomass, desired biochar properties, organic and inorganic phases, and the significance to the agronomic applica

关键词： Resveratrol   ?-cyclodextrin   Oxidized gellan gum   Resistant starch   Hydrogel bead   In vitro release  

摘要： Hydrogel beads composed of oxidized gellan gum (OGG) and resistant starch (RS) were successfully fabricated by ionic cross-linking and used as delivery carriers for resveratrol. Firstly, OGG with different degrees of oxidation were prepared through 2, 2, 6, 6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated oxidation, and characterized by Fourier transform infrared spectroscopy and carbon-13 nuclear magnetic resonance to prove that carboxyl groups were successfully introduced into the gellan gum molecules. Molecular weight, thermal stability, zeta potential and gelation temperature of OGG were also investigated. Subsequently, resveratrol was encapsulated into OGG/RS hydrogel beads in the form of resveratrol/?-cyclodextrins inclusion complexes. The addition of RS significantly influenced the morphological structure and swelling capacity of OGG/RS hydrogel beads. The OGG/RS hydrogel beads exhibited a pH-sensitivity and high encapsulation efficiency of resveratrol (84.95 %?90.73 %). Furthermore, the in-vitro release behaviors demonstrated that OGG/RS hydrogel beads showed good stability in simulated gastric fluids and sustained release of resveratrol in simulated intestinal fluids. The obtained results indicate that OGG/RS hydrogel beads show a potential as delivery system for resveratrol in the food industry.

关键词： Hydroxyapatite   In vitro bioactivity   Sol-gel processes   TiO2   Ag2O  

摘要： This research presents an investigation on the simultaneous effect of titanium (Ti) and silver (Ag) on structural and biological behaviors of the co-substituted 585 bioactive glass. Structural and morphological characterizations were studied by means of X-ray diffraction (XRD) analysis, Fourier transform infrared spectrum (FTIR), scanning electron microscopy (SEM) as well as Energy-dispersive X-ray Spectroscopy (EDS) analysis. The structural results exhibited that the hydroxyapatite)HA) layer was formed on the T/A-BGs after the 7th day of immersion in simulated body fluid)SBF(solution and increased overtime. Furthermore, the trend of cell proliferation and antibacterial activity were the same and by increasing Ag percentage up to 8 mol.% firstly, mentioned properties increased and then decreased. Hence, T/A-BG containing fixed 5 mol.% Ti and 2 mol. % Ag (TA2 (indicated higher in vitro biological performance compared to other synthesized T/A-BGs and suggested as an optimal specimen for further clinical applications.

关键词： Nanoencapsulation   Nanotechnology   Rhamnolipids   Biosurfactants   Lipid nanosystems  

摘要： In this work rhamnolipids were evaluated as surfactants for the production of nanostructured lipid carriers (NLCs). NLCs were produced by melt-emulsification using ultra-homogenisation followed by ultrasonication and different ratios of medium-chain-triglycerides and glycerol monostearate (lipid phase) were tested. NLCs presented sizes and polydispersity index values ranged between 97 and 120 nm and 0.20-0.26, respectively. Transmission electron microscopy observations confirmed the size and the spherical morphology of the NLCs. The thermal analysis and X-ray diffraction showed that the amount of solid lipid (glycerol monostearate) influences the melting, crystallisation and enthalpy of NLCs and their degree of crystallinity. Results showed that NLCs were more stable at 4 degrees C and the best formulation (1% of water phase, 0.05% of biosurfactant and solid: liquid ratio of 10:90) was stable for 30 days. This work showed the possibility of using rhamnolipids to produce NLCs and represent an important step for the development of lipid-based nanosystems using biosurfactants.

关键词： Physicochemical properties   Geopolymer   Graphene oxide   In-situ reduction   DFT calculations  

摘要： In this work, the physicochemical properties of palm oil fuel ash (POFA) based geopolymers with the addition of graphene oxide (GO) were investigated. Geopolymer composites were prepared by mixing the treated POFA, sand, NaOH, Na2SiO3, and GO. The mixtures were then cast in mortar molds to form the geopolymer composites, with different GO proportions and curing temperatures applied to the composites. Compressive strength, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) analyses, as well as density functional theory (DFT) calculations, have been performed. The compressive test results showed that the compressive strength increased proportionally with the increase of GO content and decreased when there was an excess of GO. The excessive GO and the limited amount of NaOH activator solution inhibited the formation of reduced graphene oxide (rGO) via an in-situ reduction mechanism. The FTIR and SEM analyses revealed that the excess GO tended to promote the formation of epoxy groups on the GO, which eventually confined the formation of dense agglomeration and led to a decrease in compressive strength. The DFT calculations confirmed the significance of the epoxy group stretching. Overall, the ratio of NaOH to GO is a crucial factor in determining the mechanical properties of geopolymers-GO composites.

关键词： Cerasus humilis pectic polysaccharides   RG-I structure   Emulsifier   Rheological modifier   Sugar-free gels systems  

摘要： Rhamnogalacturonan I (RG-I) enriched pectic polysaccharides were extracted from Cerasus humilis fruits (RPCF, RG-I: 74.46 %). Structural characterization including FTIR, XRD, NMR, HPAEC and SEM demonstrated that RPCF was a high-methoxy acetylated pectin macromolecule with abundant arabinose and galactose side chains (DM: 53.41 %, MW: 1098 kDa, (Ara + Gal)/Rha: 5.37 %). RPCF afforded additional lipid oxidation stability for emulsions, and exhibited significantly better emulsification performance than citrus pectin. In addition, RPCF formed a weak gel network that stabilized the emulsions (G ' > G ''). Interestingly, RPCF had behaviors that are divergent from those of commercial high-methoxy pectin because it demonstrated potential in forming sugar-free gels systems. Overall, Cerasus humilis is a new source of pectin rich in RG-I. RPCF can be used as a novel emulsifier with gelling and antioxidant effects, providing its alternative application as a natural emulsifier and rheological modifier in a wide range of products, including those with oil-in-water and low sugar.

关键词： Cocoyam   Cormels   Physico-chemical properties   Starch   Paste   Digestibility  

摘要： The corms of cocoyams, specifically Colocasia esculenta (L.) Schott and Xanthosoma sagittifolium (L.) Schott are usually consumed as pastes. Nevertheless, the secondary corms, also named cormels, are not fully exploited. In this study, the chemical composition and functional properties of cormels from different botanical sources were evaluated, and the digestibility of the resulting pastes investigated. Colocasia spp. flour contained significantly higher protein (10.32% vs 9.65%), ash (5.65% vs 5.05%) and oxalates (0.32% vs 0.22%) content, and exhibited lower Amylab gel strength (773 g vs 1040 g) than Xanthosoma spp. flour. In the resulting pastes, micrographs revealed that starch gelatinization depended on cocoyam variety. Indeed, the very tight and closed microstructure of pastes containing Colocasia spp. flour led them to better stability during storage with lower syneresis. Lower protein digestibility was obtained in Colocasia spp. gels (67.56% vs 70.91%), but they showed faster (higher k) in vitro starch hydrolysis (0.0140 vs 0.0050) with lower estimated glycemic index (61.29 vs 65.84) than Xanthosoma spp. gels. The present findings offer ways to develop cocoyam based foods by using cormels, enhancing the applicability of cocoyams.

关键词： Coal   Compound reagents   Liquid nitrogen freeze-thaw cycle   Micro physicochemical characteristics   Combined modification mechanism  

摘要： To meet urgent demands for efficient resources and sustainable development, an experimental study on combined physicochemical modification of coal was carried out. After 49 tests analyzed of single-factor experiment and orthogonal experiment, it was found that MW (mine water), 6% SLS (sodium N-lauroyl sarcosinate), 10% HNO3 and 3% [Bmim]Cl (1-Butyl-3-methylimidazole chloride), freeze-thaw cycle 8 times, and freeze-thaw time of 1.25 h each time was the best physicochemical modification scheme. Compared with raw coal, the wettability, porosity and permeability of the treated coal are significantly increased. Under the synergy of the combined physicochemical modification (including hydrogen bonding and tight filling) and the multi-field coupling (including temperature field, stress field and deformation field), the porosity is at an increase rate of 335.65%;the permeability is at an increase rate of 882.24%;while surface tension of the compound reagent is reduced to 16.24 mN/m. Furthermore, the relative content of C?C bonds and C?H bonds on coal surface increases greatly, while the relative content of C-O and COO decreased gradually, with a decrease rate of 57.61%. The results of this paper are beneficial to achieve efficient co-mining of coal and coalbed methane, and further improve safety and efficient production levels of coal mines.