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关键词： Acidity   Firmness   Maturation stage   pH value   Starch content   VSWIR  

摘要： measurement of physicochemical properties of fruits during maturation stages can help having proper fruit management. Spectroscopy data analyzing and processing is among the commonly used methods that enable nondestructive accurate property estimation. Non-destructive linear (partial least squares regression, PSLR) and nonlinear (artificial neural network, ANN) regression estimation of different physicochemical properties including firmness, acidity (pH) and starch content of 160 Fuji (Malus pumila) apple fruit samples at various maturity stages using visible and short wave near infrared (VSWIR) spectroscopic data in wavelength range 400-1000 nm is investigated with the following steps: (1) harvesting 160 Fuji apple samples at four different maturation levels;(2) extracting spectral data in wavelength range of 400-1000 nm;extracting physicochemical properties of tissue firmness, acidity (pH) and starch content;(3) pre-processing the reflectance spectra from each sample;(4) selecting effective wavelength values for each chemical property;and (5) non-destructive estimation of tissue firmness, acidity (pH) and starch content using spectral data range 400-1000 nm and spectral data based on effective wavelengths, by means of an ensemble average artificial neural network method. Results show that the neural ensemble reached similar results when using VSWIR spectral data content (wavelength range) and fixed effective selected NIR wavelengths. Correlation coefficients estimating tissue firmness, acidity (pH), and starch content were 0.800, 0.919, and 0.940 for VSWIR spectral data (linear PLS regression), 0.826, 0.947, and 0.969 for VSWIR spectral data (non-linear ANN), 0.827, 0.946, and 0.969 for fixed NIR effective wavelengths (non-linear ANN). Mean +/- std. regression coefficients (R) for tissue firmness, acidity (pH), and starch content were 0.717 +/- 0.113, 0.786 +/- 0.131, and 0.941 +/- 0.013 for Vis/NIR spectral data (linear PLS regression), 0.849 +/- 0.017, 0.930 +/-

关键词： Marinated egg   Gelation   Braising   High temperature  

摘要： In this paper, changes in physicochemical properties, gel structure and in vitro digestion of marinated egg with spice or tea during braising were investigated. Results indicated that the moisture content and surface hydro-phobicity of marinated egg white showed an overall decreased trend. The springiness of marinated egg white showed an increased trend, and the hardness in the late stage showed an increased trend. Microstructure showed that compact gel structures formed many holes during the braising. Intermolecular forces showed that ionic bonds and disulfide bonds played a dominant role in the marinated egg white. Secondary structure showed that the beta-turn showed a decreased trend, contrary to that of random coils and alpha-helices. Appropriate braising in-creased the digestibility of marinated egg white, but excessively long-time braising could reduce it. Both spice and tea braising could improve the gel strength of protein, and the tea braising was also slightly better than spice braising.

关键词： Oil-in-water emulsion   Emulsion stability   Lecithin  

摘要： The effects of lecithin addition at different concentrations (0-2.0%) on the physicochemical and emulsifying properties of mussel water-soluble proteins (MWP) were investigated. In solution system, low lecithin concentration (0.5%-1.0%) induced the aggregation and increased turbidity of composite particles. Lecithin addition caused changes in secondary structure and induced partial unfolding of MWP. Hydrophobic interactions between MWP and lecithin may contribute to the exposure of chromophores and hydrophobic groups of MWP. The interfacial tension decreasedwith lecithin addition. However, at a high lecithin concentration (1.5%-2.0%), the degree of aggregation and state of unfolding alleviated due to competitive adsorption. In emulsion system, with the low concentration of lecithin addition (0.5%-1.0%), droplet size and surface charge of emulsion decreased. The emulsion activity index, emulsion stability index, percentage of adsorbed protein increased. Both creaming stability and viscoelastic properties improved. At an intermediate lecithin concentration (1.0%), the emulsion showed the highest physical stability, while further addition of lecithin caused a slight deterioration in emulsifying properties. Overall, these results indicated the possibility that the lecithin-MWP mixed emulsifiers can be used to obtain emulsions with desirable properties. (C) 2020 Elsevier B.V. All rights reserved.

关键词： SARS Coronavirus   Homology modeling   RdRp   Azafluorene   ADMET   MM-GBSA  

摘要： The crystal structures of 2-(1H-indol-3-yl)-4-phenyl-5H-indeno [( Cheng et al., 2007;Lee et al., 2003) 1,21,2-b]pyridine-3-carbonitrile (la) and 2-(1H-indol-3-yl)-4-(4-methoxyphenyl)-5H-indeno [( Cheng et al., 2007;Lee et al., 2003) 1,21,2-b]pyridine-3-carbonitrile (Ib) were determined using single crystal Xray diffraction. Both the compounds belong to the triclinic system with the P-1 space group. The azafluorene ring system in both the compounds is effectively planar. The intermolecular interactions present in the compounds are discussed using Hirshfeld surface analysis, QTAIM and NCI. Compound Ib formed a strong interaction (-24.174 kJ/mol) with the solvent molecule. Both the compounds were geometry optimized using DET/B3LYP level of theory. The compound's drug-like behaviors were studied using HOMO-LUMO analysis. The homology modeling of SARS CoV-2 RdRp was done utilizing the PDB 6NUR_A as a template. The model showed above 99% similarity with its preceder SARS CoV. The molecular docking analysis of the synthesized compounds was carried out along with some suggested drugs for COVID-19 and some phytochemicals. The docking results were then analyzed. The binding free energy of the complexes were calculated using MM-PB(GB)SA and ADMET properties of Ia and Ib were also predicted. Some suggestions are given from this analysis. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Starch   Polyol sugar   Ultrasound-assisted pregelatinization   Aggregation structure  

摘要： The present research investigated the aggregation behaviors of different levels (4, 8 and 12%) of incorporation of sucrose, isomalt and maltodextrin to pre or post- ultrasonication (400 W, 10 min at 60 degrees C) by fourier transform infrared spectroscopy (FTIR), microstructure by scanning electron microscopy (SEM), water absorption, pasting by rapid visco analysis (RVA), and thermal by differential scanning calorimetry (DSC). FTIR results showed that the aggregation process between polyol and starch after ultrasonication is more effective than before ultrasonication owning to more hydroxyl groups of polyols are engaged with the hydrogen bonds of starch which is more pronounced peaks at 1500-1750 cm(-1), 1700-2700 cm(-1) and 3000-3700 cm(-1). These findings are in line with the results from SEM analysis. The spots, deformations and cross-linking created by the polyols were more significant after ultrasound assisted pregelatinizion. Impact intensity of polyol on starch granule was reduced in the following order: isomalt > sucrose > maltodextrin. RVA profiles showed that through the incorporation of polyols after sonication, were higher in samples pregelatinized in comparison with those before sonication. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Ti-Nb-Ta-Zr alloys   Mechanical properties   Structural properties   Physicochemical properties   Implantation  

摘要： A technology for producing a new homogeneous Ti-20Nb-13Ta-5Zr alloy has been developed. It is shown that the alloy is single-phase with a beta-Ti type crystal lattice. The alloy has the required mechanical properties (tensile strength of about 745 MPa). On the surface of plates and wire made of alloy, a relief of micro- and nanoscale is observed. In terms of the ability to generate reactive oxygen species and long-lived reactive protein species, the Ti-20Nb-13Ta-5Zr alloy is more preferable than nitinol. It was established that cell cultures growing on plates or wire made of Ti-20Nb-13Ta-5Zr alloy had a significant mitotic index (2%). The number of viable cells was at least 95-96% of the overall cell count. According to the results of implantation of the alloy in the form of plates or wire ring to animals, it can be concluded that the alloy is biocompatible. The morphology of the surface of the samples did not change after biological experiments. It can be assumed that the alloy Ti-20Nb-13Ta-5Zr is a material potentially suitable for medical applications.

关键词： Averrhoa bilimbi   Edible film   Film characterization   Pectin   Structural characteristics  

摘要： The potential of Averrhoa bilimbi pectin (ABP) as a source of biopolymer for edible film (EF) production was explored, and deep eutectic solvent (DES) (1% w/w) containing choline chloride-citric acidmonohydrate at a molar ratio of 1:1 was used as the plasticizer. The EF-ABP3:1, which was produced from ABP with large branch size, showed a higher value of melting temperature (175.30 degrees C), tensile stress (7.32 MPa) and modulus (33.64MPa). The EF-ABP3:1 also showed better barrier properties by obtaining the lowest water vapor transmission rates (1.10-1.18mg/m(2).s) and moisture absorption values (2.61-32.13%) depending on the relative humidity compared to other EF-ABPs (1.39-1.83mg/m(2).s and 3.48-51.50%, respectively) that have linear structurewith smaller branch size. Fromthese results, itwas suggested that the galacturonic acid content, molecularweight, degree of esterification and pectin structure of ABP significantly influenced the properties of EFs. The interaction of highly branched pectin chains was stronger than the linear chains, thus reduced the effect of plasticizer and produced a mechanically stronger EF with better barrier properties. Hence, it was suggested that these EFs could be used as alternative degradable packaging/coating materials. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Zirconia-alumina   Copper   Methanol steam reforming   Highly dispersed catalysts   Hydrogen  

摘要： ZrAl materials with different compositions have been synthesized by the hydrothermal method and used as supports of Cu catalysts for hydrogen production from methanol steam reforming (MSR). The effect of the support composition, Zr/Al ratio, on the physicochemical and catalytic properties of CuZrAl catalysts was studied. The characterization results show that there is an optimal support composition (Zr/Al ratio of 0.4), allowing to achieve the highest methanol conversion due to enhanced dispersion and reducibility of copper. Zr-rich catalysts displayed low MSR activity, which is likely due to the segregation and crystallization of zirconia, resulting in the formation of large copper particles with lowered dispersion and reducibility. The catalyst with the optimal Zr/Al ratio shows the highest methanol conversion, enhanced selectivity and good long term stability, rendering this catalyst a promising material for the production of high purity H-2 from MSR.

关键词： Carbohydrate radicals   EPR   Functional properties   GPC   Octenyl succinate starch   Starch structure   XRD  

摘要： The aim of this paper was to evaluate the effect of thermal treatment and UV irradiation on structural and physicochemical properties of octenyl succinate (OS) maize starches differing in content of OS groups (0.76%-2.38%). X-ray diffraction (XRD), gel permeation chromatography (GPC), and electron paramagnetic resonance (EPR) spectroscopy were used to estimate structural characteristics of octenyl succinate starches and their physically treated counterparts. Starch functional properties were also determined. XRD spectra and hydrodynamic volume distribution revealed that growth of octenyl succinate groups' content resulted in stabilization of starch structure, which was confirmed by processes of radical formation, stimulated by thermal and UV treatments. It was found, on the basis of measurements of water binding capacity, water solubility and intrinsic viscosity, that OSA addition changed physicochemical properties of starch and influenced the course of physical modifications. It was established that temperature affected starch properties to a greater extent than UV.

关键词： Vermiculite-phlogopite   Physicochemical properties   Phase analysis   Organo-mineral complexes   Soil amelioration  

摘要： Physicochemical properties of expanded vermiculite-phlogopite products from Kovdor (Murmansk region, Russia) used for 15 years as a hydroponics substratum were studied. The four investigated samples were as follows: natural vermiculite, initial expanded (roasted at 700 degrees C) vermiculite, spent expanded vermiculite and spent vermiculite roasted again at the same temperature. Data on the bulk density, field capacity, hygroscopicity, and expansion coefficients showed that the degradation of the substratum was accompanied by mechanical destruction, reduction of water absorption by half, and transformation of mineral phases. The structural transformation of expanded vermiculite was studied using X-ray diffraction (XRD), thermogravimetric analysis (TG), and differential scanning calorimetry (DSC), coupled with a mass spectrometric analysis of the released gases. Under conditions with a sufficient supply of plants with potassium of nutrient solution, a change in the mineral composition occurred: a decrease in the content of vermiculite and an increase in phlogopite. The formation of organomineral complexes on the surface of the vermiculite was detected. There was no noticeable change in the chemical composition of the expanded vermiculite during its use in hydroponics. In essence, the levels of potentially toxic elements (Mn, V, Ni, Cr, Co, Cu, Zn) met environmental regulations, and the levels of major elements (Mg, Ca, K, Fe, Mn) corresponded to those found in natural vermiculite. The chemical composition and structure of spent vermiculite allows its use as an ameliorant to improve soil, water, and air regimens.