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关键词： Grain hardness   Meal   Flour   Gluten   Solvent retention capacity   Farinograph   SDS-PAGE   Pasting  

摘要： The physicochemical and functional characteristics of grain, meal and flour of timely sown wheat (TSW) and delayed sown wheat (DSW) were compared to see the effects of heat stress (HS). TSW and DSW of different lines were sown as per the approved timings. DSW experienced higher temperature during flowering and had shorter vegetative and maturation period than TSW. Pasting and dough rheological properties were measured using Rapid Visco-Analyser and Farinograph, respectively, while gliadins and glutenins profiling was done by SDS-PAGE. Delayed sowing decreased grain yield and diameter while increased protein and all categories of gliadins and high molecular weight glutenins. DSW showed higher peak viscosity, breakdown-viscosity and dough stability and lower setback viscosity, damaged starch, arabinoxylans and water absorption than TSW. HS in DSW appeared to lower starch synthesis causing proportionate increase in grain hardness and proteins content leading to changes in milling and rheological characteristics.

关键词： Naphthalene-1,4,5,8-tetracarboxylic acid   Synthetic ester   Tribological property   Lubricant  

摘要： Ester oils (1,4,5,8-4C(n)) were synthesized through esterification of naphthalene-1,4,5,8-tetracarboxylic acid with aliphatic alcohols. The molecular structures were confirmed with H-1 NMR, C-13 NMR, FT-IR and elemental analysis. Their KV, VI, FP, PP, oxidation and thermal stabilities, friction reducing and anti-wear performances were measured. The results demonstrate that the 1,4,5,8-4C(n) have obviously higher thermal and oxidation stabilities than the existing esters DOS, PIS and Phe-3C(i8). They also have predominant tribological behavior at both 50 degrees C and 120 degrees C. Analyzing from the results of ECR, QCM and XPS, it could be concluded that strongly and orderly physicochemical adsorption of the 1,4,5,8-4C(n) molecules on the sliding surfaces is the critical factor for these oils to demonstrate excellent tribological performance for steel contacts. (C) 2021 Elsevier B.V. All rights reserved.

关键词： Sodium oleate   Green formulation   Viscoelasticity   Soft matter   Wormlike micelles  

摘要： Hypothesis: The structure, rheology and other physicochemical properties of dilute aqueous dispersions of sodium oleate (NaOL) are well known. This paper is the first report in which a moderately concentrated (13% w/w) dispersion of NaOL in water is investigated. In fact, at this concentration the phase and rheology behavior of the surfactant remarkably deviates from those of its dilute solutions in water and a significant effect is imparted by the addition of potassium chloride. Experimental: The structural, thermal and rheological properties of a 13% w/w dispersion of NaOL in water were investigated by cryo-TEM, rheology, and DSC experiments with and without the addition of potassium chloride. The system is comprised of elongated wormlike micelles that turn into a gel like more disordered viscous material upon addition of small amounts of KCl (4% w/w). Findings: This paper illustrates the multifaceted behavior of sodium oleate dispersions at intermediate concentrations that depends on the presence of other cosolutes (such as KCl). The results show that viscoelastic aqueous dispersions of NaOL are excellent candidates for the preparation of stimuli-responsive green materials to be used in a number of different applications. We also discuss the genesis of wormlike micelles (WLMs) in terms of the general theory of self-assembly. (c) 2021 Elsevier Inc. All rights reserved.

关键词： Sol-gel processes   Bioactivity   MgO   Biomedical applications  

摘要： Novel pyrophosphate glass ceramic scaffolds (3D-Ca-P-2) were fabricated and coated with several layers of CaO-P2O5-SiO2-MgO [3D-[Ca/P/Si]-XMg (X = 1,3 and 10 mol%)] as potential bioactive scaffolds for bone regeneration. The core scaffolds present a homogeneous distribution of polygonal grains consisting of 97% Ca2P2O7 with CaO-P2O5 glass as the matrix phase. Incorporating MgO into coatings led to extremely porous layers, assembled by nanosized equiaxed particles, which favoured the formation of different phases of tricalcium phosphate instead of pyrophosphate. Possible applications were determined based on Standard ISO/FDIS 23317:2014 for ceramics and powder samples. The 3D-Ca-P-2 scaffolds' non-bioactivity was modulated by coatings of different bioactivity behaviours depending on MgO contents. 3D-[Ca/P/Si]-10Mg was the best scaffold as precipitated hydroxyapatite (HA), was more amorphous than in the other scaffolds because Mg was incorporated into the HA network, which could favour subsequent cell adhesion. The multilayer scaffold provides advantages over others developed until now because in a unique structure all the characteristics required for an implant are combined. On a physical level, mechanical resistance, and porosity, and on a chemical level, a combination of calcium phosphate phases, similar to the mineral phase of bone, doped with Mg ions, which are capable of being transformed into HA in different periods of time.

关键词： Resistant starch   Pearl millet   Functionality   Food applications  

摘要： Pearl millet (Pennisetum glaucum (L.) ***.) is a sustainable and underutilized starch source, constituting up to 70 % starch in its grain. Pearl millet could be used as a cheaper source of starch as compared to other cereals for developing functional foods. This review is mainly focused on isolation methods, and chemical composition of the pearl millet starch (PMS). Techno-functional characteristics such as;gelatinization, pasting properties, solubility, swelling power, and digestibility to infer wider application of the PMS critically highlighted in the review. Native starches have limited functionalitiesfor food applications due to the instability in developed pastes and gels. A number of modifications (physical, mechanical and enzymatic) have been developed to increase the functionality and to obtain desired characteristics of PMS thus improving its utilization in food applications. Further, the utilization of native as well as modified PMS is also discussed comprehensively. In addition, a number of recommendations to further improve its functionality and increase its application are also discussed.

关键词： Novel gelling agent   Gelatine replacement   Antimicrobial activity   Gel characterisation  

摘要： A novel innovative viscoelastic gelling agent (novel gel, NG) has been developed by combining citric acid (CA) and disodium 5-guanylate (DG). NG has the potential to replace other gelling agents such as gelatine, which has been commonly used in foods, dietary supplements, pharmaceutical and cosmetic products including ointments and sprays. NG has unique physico-chemical properties, including a wide range of concentration-dependent, temperature-sensitive gel strengths. Based on the rheological measurement results, NG depicted similar shear thinning behaviour to gelatine, within shear rates ranging from 25.8 to 129 (s(-1)). NG also significantly increased the shelf-life (by 21 days) of minced beef, as well as inhibited the growth of major spoilage pathogens, such as E. coli, S. aureus, Salmonella sp., Listeria sp., yeast and moulds, making it an ideal candidate for gelatine replacement.

关键词： Hydrogen   Redox reactions   Hydrocarbons   Aromatic compounds   Carbon  

摘要： This Perspective presents recent advances in our in knowledge of the fundamental elementary mechanisms involved in the low- and high-temperature molecular mass growth processes to polycyclic aromatic hydrocarbons in combustion systems and in extraterrestrial environments (hydrocarbon-rich atmospheres of planets and their moons, cold molecular clouds, circumstellar envelopes). Molecular beam studies combined with electronic structure calculations extracted five key elementary mechanisms: Hydrogen Abstraction-Acetylene Addition, Hydrogen Abstraction-Vinylacetylene Addition, Phenyl Addition-DehydroCyclization, Radical-Radical Reactions, and Methylidyne Addition-Cyclization-Aromatization. These studies, summarized here, provide compelling evidence that key classes of aromatic molecules can be synthesized in extreme environments covering low temperatures in molecular clouds (10 K) and hydrocarbon-rich atmospheres of planets and their moons (35-150 K) to high-temperature environments like circumstellar envelopes of carbon-rich Asymptotic Giant Branch Stars stars and combustion systems at temperatures above 1400 K thus shedding light on the aromatic universe we live in.

关键词： Catalytic reactions   Oxidation   Reactivity   Particulate matter   Permeability  

摘要： In this work, we present a multiscale experimental and modeling study focusing on the reactivity and flow permeability characteristics of the soot, relevant for SCR-coated particulate filter applications. Extensive kinetic studies on a synthetic gas bench were initially conducted to understand the role of NO2 on soot oxidation, employing both uncoated and SCR-coated filters. Experimental results suggest that carbon reactions with O-2 and NO2 are not a simple superimposition and that strong synergistic phenomena between the two are present. These results were used to calibrate a physicochemically informed SCRoF mathematical model, which was subsequently validated against engine tests, confirming the need for an extended soot reaction mechanism. Irrespectively of the filter coating, the size of the emitted soot particles seems to affect the reactivity of the soot. Soot deposits with a smaller mean particle size were experimentally found to exhibit a higher soot oxidation rate and correlated with the higher available surface area. Next, the backpressure increase, associated with the addition of SCR coating, was evaluated by direct comparison of a DPF and a SCRoF. Experimental results showed that the rate of flow-resistance increase with increasing soot loading is different between the two filters, indicating a dependency of the soot physicochemical properties from the catalytic coating. The backpressure behavior of SCRoF was also evaluated under regeneration conditions, where a nonlinear decrease was observed with decreasing soot loading. Then, the accuracy of the soot deposition/oxidation model was evaluated, employing destructive methods to characterize the in-filter axial soot distribution profiles under both reacting and nonreacting conditions. In a final step, transient driving cycle sequences were performed to evaluate the correlation between backpressure and the accumulated soot amount inside the filter.

关键词： Ionic liquids   Gas chromatography   Quantitative structure-retention   relationships   Physiochemical properties   Solvation parameter model   Partition constants   Infinite dilution activity coefficients   Solubility parameters  

摘要： Over the years room temperature ionic liquids have gained attention as solvents with favorable environmental and technical features. Both chromatographic and conventional methods afford suitable tools for the study of their physicochemical properties. Use of gas chromatography compared to conventional methods for the measurement of physicochemical properties of ionic liquids have several advantages;very low sample concentrations, high accuracy, faster measurements, use of wider temperature range and the possibility to determine physicochemical properties of impure samples. Also, general purpose gas chromatography instruments are widely available in most laboratories thus alleviating the need to purchase more specific instruments for less common physiochemical measurements. Some of the main types of physicochemical properties of ionic liquids accessible using gas chromatography include gas-liquid partition constants, infinite dilution activity coefficients, partial molar quantities, solubility parameters, system constants of the solvation parameter model, thermal stability, transport properties, and catalytic and other surface properties. (c) 2021 Elsevier B.V. All rights reserved.

关键词： SARS-CoV-2 classification   machine learning   support vector machines   physicochemical properties  

摘要： There is an urgent need to elucidate the underlying mechanisms of coronavirus disease (COVID-19) so that vaccines and treatments can be devised. Severe acute respiratory syndrome coronavirus 2 has genetic similarity with bats and pangolin viruses, but a comprehensive understanding of the functions of its proteins at the amino acid sequence level is lacking. A total of 4320 sequences of human and nonhuman coronaviruses was retrieved from the Global Initiative on Sharing All Influenza Data and the National Center for Biotechnology Information. This work proposes an optimization method COVID-Pred with an efficient feature selection algorithm to classify the species-specific coronaviruses based on physicochemical properties (PCPs) of their sequences. COVID-Pred identified a set of 11 PCPs using a support vector machine and achieved 10-fold cross-validation and test accuracies of 99.53% and 97.80%, respectively. These findings could provide key insights into understanding the driving forces during the course of infection and assist in developing effective therapies.