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关键词： Ultrasonic speed   Viscosity   Acetonitrile   Alkyl acrylates   Excess properties   Intermolecular interactions  

摘要： The ultrasonic speeds, u and viscosities, eta of binary mixtures of acetonitrile with alkyl acrylate (methyl acrylate, ethyl acrylate, n-butyl acrylate and t-butyl acrylate) over the entire composition range were measured at temperatures (293.15, 298.15, 303.15, 308.15, 313.15, and 318.15) K and at atmospheric pressure. From the experimental data, the excess isentropic compressibility, k(s)(E), excess ultrasonic speed, u(E), excess molar isentropic compressibility, K-s,m(E) and deviations in viscosity, Delta eta have been calculated. The partial molar isentropic compressibilities and excess partial molar isentropic compressibilities over whole composition range, partial molar isentropic compressibilities and excess partial molar isentropic compressibilities of the components at infinite dilution are calculated. The variation of these parameters is discussed in terms of molecular interactions in these mixtures. The viscosities of these mixtures were correlated using various models and the ultrasonic speeds of these mixtures were theoretically calculated using scaled particle theory and the results are compared with experimental values. (C) 2021 Elsevier Ltd.

关键词： A-type granules   B-type granules   starch properties   wheat cultivars  

摘要： Background and objectives: In this study, the characteristics of A- and B-type starch granules from three wheat cultivars exhibiting weak, medium, and strong gluten forces were investigated. It was analyzed the wheat flour chemical composition and gluten content, wet starch extraction yield, and the physicochemical, morphological, and digestion properties of isolated A- and B-type starch granules. The starches were characterized for swelling power, solubility, pasting properties, gel texture profile, thermal properties, relative crystallinity, morphology, and in vitro starch digestibility. Findings: The starch extraction yield was higher for the wheat sample exhibiting weak gluten force, followed by the samples with medium and strong gluten. There was no difference between the A- and B-type starch granules regarding starch extraction yield. The wheat starch physicochemical properties varied depending on gluten force and starch granule size, specified as A-type or B-type. Weak gluten-containing wheat starch displayed a slower glucose release compared with the medium- and strong gluten-containing samples. A-type granules exhibited slower in vitro starch digestibility and digestion rate in the small intestine in all cultivars. Conclusions: The obtained results allow a great application diversity of wheat starch granules through their separation based either on the genotype or on the granule size. Significance and novelty: Starch extraction from wheat with different gluten forces could be an alternative to obtain starch with different characteristics as well as the separation of A- and B-type granules that would fulfill the needs of specific markets.

关键词： ?Betaone? barley   Germination   ?-Glucan   Bioactive compounds   Antioxidative capacity  

摘要： This study was conducted to investigate the effects of germination on the bioactive phytochemicals in the barley variety ?Betaone?, which has high ?-glucan content. Betaone barley seeds were germinated for 24, 48, 72, and 96 h at 25 ?C in a growth chamber. As the germination period progressed, crude protein, crude fat, and crude ash levels increased, while starch content decreased. ?-Glucan content significantly decreased during the germination period. However, after 96 h of germination, it was still 4.31%, which is similar to the amount found in ordinary barley varieties. The ?-and ?-amylase activities in Betaone barley increased, thereby significantly decreasing pasting viscosities (p ? 0.05), as germination progressed. The water absorption index increased in the early germination stage, subsequently decreasing as germination progressed. While the water solubility index fell in the first stage of germination, it subsequently increased as germination progressed. Oil absorption decreased as germination progressed. Bioactive compounds, in particular the total phenolic (122.84?322.67 ?g/g), total flavonoid (32.20?124.09 ?g/g), and GABA content (176.94?212.64 ?g/g), increased as germination progressed. The antioxidative properties mainly DPPH and ABTS radical scavenging activity also increased during the germination period. Therefore, these findings could be a useful method for improving new products with enhanced bioactive phytochemicals. ? 2021 Elsevier B.V. All rights reserved.

关键词： Amaranth   Isolation   Mechanical separation   Crystalline orthorhombic structure  

摘要： This work focused on the physicochemical properties of isolated Amaranth starch. Inductively coupled plasma (ICP) showed that amaranth is low-lipid calcium and magnesium source for the human diet. Scanning Electron Microscopy showed that isolated granules are in the range of sub and micro size. DSC starch thermogram showed a gelatinization temperature of 67.9 degrees C and an enthalpy of 10.6 J/g suggesting the presence of an ordered crystalline structures. High-resolution X-ray diffraction showed the isolated starch contents nanocrystals with an orthorhombic crystalline structure whose pattern was indexed. The pasting profile showed that this kind of starch has an end cold viscosity as a custard, making it useful for infantile formulations. It does not present dynamic viscosity and would not be a problem when swallowed. A very important finding in this work was that the orthorhombic nanocrystals, after solvation during gelatinization, do not contribute to the apparent viscosity development. (c) 2021 Published by Elsevier B.V.

关键词： Bacillus cereus  

摘要： The aim of this study was to evaluate the physicochemical, nutraceutical, antioxidant, and antibacterial properties of tunichrome released from Persian Gulf tunicate (Phallusia nigra). For this purpose, molecular weight (SDS-PAGE), amino acid profile, chemical composition (GC-MS), mineral composition, functional groups (FTIR), total phenol content (TPC), total flavonoid content (TFC), antioxidant activity, and antimicrobial properties were investigated. The results showed that tunichrome contained a high amount of essential amino acids (i.e., Lys = 32.24 mg/100 g) and essential minerals. According to GC-MS results, tunichrome had different antioxidant and antimicrobial components. The TPC and TFC of tunichrome were 0.55 mg GA/g and 0.21 mg quercetin/100 g, respectively. Tunichrome showed higher antioxidant activity than ascorbic acid, and its radical scavenging activity values were increased from 30.28 to 82.08% by increasing concentration from 50 to 200 ppm. Inhibition zones of Staphylococcus aureus, Bacillus cereus, Salmonella enterica, and Escherichia coli O157:H7 were 14, 18, 17, and 15 mm, respectively. Moreover, the minimum inhibitory concentration values of tunichrome for S. aureus, Bacillus cereus, S. enterica, and E. coli O157:H7 were 1.17, 0.59, 0.59, and 1.17 mg/ml, respectively. The minimum bacterial concentrations were 2.34, 1.17, 1.17, and 2.34 mg/ml for S. aureus, Bacillus cereus, S. enterica, and E. coli O157:H7, respectively. These results showed that tunichrome of Phallusia nigra has excellent biological effects as a bioactive compound for food fortification.

关键词： Fermentation  

摘要： This study aimed to evaluate the influence of lactic acid bacteria fermentation on the physicochemical properties and antioxidant activity of chickpea yam milk. Four groups of chickpea milk were prepared through fermentation with lactic acid bacteria for quality and functionality improvement. Results indicate that the polysaccharide content of four samples declines during the fermentation process, and their infrared spectrums are similar with a slight difference in the transmittances of some characteristic bands. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) profiles of four samples with 24 h fermentation showed a band disappearance in the range of 94.3 KDa and generation of many small-molecule peptides, revealing the protein degradation during fermentation. The moderate enzymatic hydrolysis had no adverse effect on the texture and color of the samples. A substantial increase in DPPH, ABTS radical scavenging rates, and FRAP value was observed after 12 h fermentation, especially the CPBY sample. The present results indicate that lactic acid bacteria fermentation can be used to improve the physicochemical properties of samples and enhance their antioxidant activity.

关键词： Salts   Anions   Cations   Electrolytes   Electrodes  

摘要： Ionic liquid-type electrolytes (ILELs) based on boronium cations, (trimethylamine)(dimethylethylamine)-dihydroborate [N111N112BH2](+), are revisited as they have barely been studied for Li battery applications as alternatives to the ubiquitous [C(x)mpyr](+) and [R4P](+) cations. We demonstrate the potential of binary and ternary ILELs with bis-(trifluoromethanesulfonyl)imide [TFSI](-) and bis(fluorosulfonyl)imide [FSI](-) anions in comparison with N-butyl-N-methylpyrrolidinium [C(4)mpyr] [TFSI] as a reference. The conductivity of neat ILs and their 0.5 mol kg(-1) Li-salt-containing mixtures (sigma(25)degrees(C) = 0.5-1.68 mS cm(-1)), differential scanning calorimetry (T-g = -83 to -77 degrees C, T-m = 14 to 28 degrees C), solid-solid-state transitions for [N111N112BH2] [FSI], cyclic voltammetry (electrochemical stability window 5.6 V), Li vertical bar LFP and Li vertical bar Li cells, and a crystal structure of the Li environment have been investigated. The binary mixture of [N111N112BH2][TFSI](+) 0.8 mol kg(-1) of Li[TFSI] yielded a crystalline material for which the X-ray structure showed a four-coordinate square-planar [Li(TFSI)(2)](-) environment with O boolean AND O chelation, while two-coordinate environments were reported for Li+ centers in [C(x)pyr][Li-2(TFSI)(3)] with higher anion numbers, both tetrahedral monodentate coordination by four TFSI anions and five-coordinate, square-based pyramidal coordination by three TFSI anions. Charge-discharge cycling studies were conducted on lithium metal electrodes in a symmetrical Li vertical bar Li coin cell configuration for 1500 charge-discharge cycles at 50 degrees C and a current density of 0.2 mA cm(-2). When used as an electrolyte in Li vertical bar LFP half cells, several hundred charge-discharge cycles with high initial discharge capacity (similar to 155 mA h g(-1) at 50 degrees C) and good retention (0.03 to 0.05% capacity loss per cycle) are possible at cycle rates of 0.1-0.25 C (0.07-0.2 mA cm(-2)). A good

关键词： Chalcone   dipole moment   pyrazoline   stokes shift  

摘要： The title compound 2-(3-(2,5-dimethylthiophen-3-yl)-5-(2,4,5-trimethoxyphenyl)-4,5-dihydro-1H-pyrazol-1-yl)benzo[d]thiazole (DTPH) was synthesized by the reaction of (E)-1-(2,5-dimethylthiophen-3-yl)-3-(2,4,5-trimethoxyphenyl)prop-2-en-1-one (DTPO) with 2-hydrazinyl benzothiazole under microwave irradiation. Chalcone was synthesized by the reaction of 1-(2,5-dimethylthiophen-3-yl)ethan-1-one with 2,4,5-trimethoxybenzaldehyde under same conditions. The structure of the DTPH was confirmed by the spectroscopic techniques (IR, H-1-NMR, C-13-NMR, EI-MS) and elemental analysis. The physicochemical behavior of newly synthesized DTPH was determined in different solvents. As a result of the measurements, a large red shift in the fluorescence of the DTPH studied was observed, when the polarity of the solvents increases (n-Hexane to DMSO). Optical properties of DTPH such as dipole moment, oscillator strength, stokes shift, and fluorescence quantum yields were determined in different polarities of the solvents. The effect of cationic and anionic surfactant such as CTAB and SDS on DTPH dye was also studied to determine the critical micelle concentration of CTAB and SDS surfactants.

关键词： BDE   DFT   molecular docking   RDF   TD-DFT   terphenyl  

摘要： Theoretical calculations at the B3LYP/CC-pVDZ level were used to find the IR, Raman, VCD, and various molecular properties of a terphenyl derivative. Experimental and theoretical spectra agree within their respective limits. Partial density of states shows which parts of the molecules have the most important contribution to the FMO. Fluorine, sulfur, oxygen, and nitrogen atoms have practically insignificant contribution to the HOMO. Time dependent DFT calculations were used to study excitations, while natural transition orbitals were used to study the charge transfer in the strongest excitation. The experimentally observed FTIR modes are compared with calculated wavenumbers. Natural bond orbital analysis gives the idea about stability of molecules. MD simulations are used for calculating solubility parameters. Autoxidation and bond dissociation studies indicate stability of the compound. The docked ligands form secure complexes with the receptor methionyl-tRNA synthetase which indicates new anti-protozoan drugs.

关键词： Reinforcement   Properties   Synergism   CO2 curing   Ca(OH)(2) solution drenching  

摘要： We investigated the influences of technological parameters and CO2 curing on cement slurry carbonation and concrete properties, respectively. The products of cement hydration and carbonation were studied for further analyzing the mechanism underlying the reinforcement of concrete through the combination of Ca(OH)(2) solution drenching and CO2 curing. A newly formed precipitate, aragonite-CaCO3, deposited onto the active surface and filled the concrete block's pores, thereby increasing the block's density. Consequently, results show that the synergism between CO2 curing and Ca(OH)(2) solution drenching could increase the concrete blocks' density and compressive strength. The proposed method could solve the problem of CO2 erosion of cement and concrete materials. Therefore, CO2 could be an advantageous factor for the compressive strength of concrete and less harmful to concrete. (C) 2021 Elsevier Ltd. All rights reserved.