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ISBN: (纸本)9787311062903

关键词： Derivative of carboxylic acid   triorganotin complex   spectroscopic analysis   DNA binding study   In silico study  

摘要： The ligand, (E)-4-((2-methoxyphenyl)amino)-4-oxobut-2-enoic acid, and its tri-butylstannyl (E)-4-((2-methoxyphenyl)amino)-4-oxobut-2-enoate, trimethylstannyl (E)-4-((2-methoxyphenyl)amino)-4-oxobut-2-enoate and triethylstannyl (E)-4-((2-methoxyphenyl)amino)-4-oxobut-2-enoate complexes were obtained and characterized by different techniques. The spectroscopic data revealed the presence of the OH in the FTIR and NMR spectra of the (E)-4-((2-methoxyphenyl)amino)-4-oxobut-2-enoic acid and the absence of this peak in the spectra of the complexes confirm their successful formation. The geometry confirmation was done using single-crystal X-ray diffraction and found a 5-coordinated distorted trigonal bipyramidal comprising of the O1 of the carboxylate moiety, O3 of the amide moiety occupying the axial position while the three equatorial positions were occupied by the carbon atoms of the three butyl groups. The result of the DNA interaction of the representative compounds explored an intercalative binding mode as confirmed by UV-Visible spectroscopy and viscometry. The in silico study performed by SwissADME webserver suggested that reported compounds obey the rules of drug-likeness.

关键词： Poly (vinyl alcohol)   ethylene glycol   gamma-rays   N-2 ion beam   gel fraction   micro-hardness and thermal stability  

摘要： Poly (vinyl alcohol) is blended with ethylene glycol by casting method to form PVA-EG blend films. These films were irradiated by both N-2 ion beam extracted from dc ion source at different ion fluences and gamma-rays with various irradiation doses. The effects of ion beam and gamma-rays irradiation on the thermal, micro-hardness, and gel fraction properties of PVA-EG blend films were investigated. The gel fraction % and micro-hardness increase with increasing the gamma-rays doses up to 150 kGy and then decreased, where they increased at all fluences of ion beam irradiation. The improvement in the gel fraction percentage and micro-hardness suggest that PVA-EG blend films exhibited a crosslink density. The thermal behavior was examined by thermogravimetric analysis and it shows different thermal patterns depending on the type and dose of radiation. The thermal stability parameters of gamma-rays- and ion beam-irradiated PVA-EG samples were evaluated using the Ti, Ts, T0.5, Tf temperatures, and activation energy (Ea) values. The thermal stability parameters were dependent on both the type and extent of irradiation dose and fluence. Finally, there is a good agreement between the obtained results from different measurement techniques.

ISBN: (纸本)9787522607108

关键词： Full-fat almond flour   Enzymatic extraction   Plant-based protein   Functional properties  

摘要： The need for sustainable protein sources has prompted research on several plant-based protein matrices. The effects of enzymatic extraction on the composition, physicochemical, structural, and functional properties of protein-extracts (skim) from full-fat almond flour were elucidated. Protein-extracts were produced by aqueous (AEP), and enzyme-assisted extraction processes (EAEP), which enable concurrent extraction and fractionation of lipids and proteins without the use of flammable solvents. Except for the use of 0.5% of protease in the EAEP, extraction parameters were similar for both processes (pH 9.0, 50 degrees C, 1:10 solids-to-liquid ratio, and 60 min). The use of enzyme to assist the extraction resulted in the production of protein extracts with higher protein content and promoted the formation of smaller peptides and a more unordered protein secondary structure with reduced surface hydrophobicity. These structural modifications reduced the EAEP skim protein thermostability and improved its water absorption capacity (2.4 vs. 2.7 g water/g protein) compared with the AEP proteins. Importantly, proteolysis significantly enhanced the functionality of the hydrolysates at pH values close to the almond protein isoelectric point. At pH 5.0, EAEP skim proteins had higher solubility (47 vs 23%), emulsification capacity (492 vs 402 g oil/g protein), emulsification activity index (35 vs 17 m(2) /g) and foaming capacity (23 vs 11%) compared with AEP proteins. These results indicate that moderate hydrolysis can be used to improve extractability and the functionality of almond proteins, creating new opportunities for its application as food ingredients.

关键词： Oligonucleotides  

摘要： Rationale Therapeutic oligonucleotides have molecular weights of more than 6000 Da. They typically contain chemically modified structures such as phosphorothioate (PS) and a locked nucleic acid (LNA). To determine the effect of the length and chemical modification on the physicochemical properties, various nucleic acids with different lengths and modified structures were analyzed using traveling-wave ion mobility mass spectrometry (TWIMS). Methods The physicochemical characteristics of the modified oligonucleotides were determined using IM-MS. Each oligonucleotide was evaluated by confirming the multivalent charge state drift times, collision cross-section (CCS) values, and CCS widths. Results By plotting the m/z for oligonucleotides of different lengths and the CCS values at each charge state, a bottoming-out shape plot at one charge per 4.0-3.5 bases was confirmed. Moreover, significant differences were observed in the CCS values between the PS-modified and unmodified oligonucleotides. The PS-modified oligonucleotide showed a wider CCS range that was proportional to the PS modification ratio of the oligonucleotide sequence. Conclusions The TWIMS results showed a correlation between the length and modification of oligonucleotides and the CCS values. In addition, it suggested that each charge state of the oligonucleotide ion has different physicochemical properties.

关键词： YSZ   Sintering   Reducing atmosphere   CO2+air atmosphereXPS   Electrical conductivity  

摘要： Given the need to process anodes and composites based on nano-YSZ in reducing or in air containing additional CO2 atmospheres for the fabrication of solid oxide fuel cells (SOFCs), and solid oxide electrolysis cells (SOECs), we have studied the effect of the exposure to CO+N-2/H-2 or CO2+air mixtures during sintering of YSZ green pellets, prepared from commercial nanopowders, on their structure, microstructure, chemical composition and their electrical properties. The reduced sample shows Raman bands at 1298 and 1605 cm(-1) that are assigned to the D and G bands of carbon, respectively. The bands intensity ratio ID/IG indicates a larger content of disordered carbon. X-ray photoelectron spectroscopy (XPS) shows that C is present in the reduced samples as reduced carbon. However, the samples sintered in CO2+air present C as carbonate-type. Impedance spectroscopy reveals that the highest total conductivity is for the reduced samples in the whole range of studied temperatures. In addition, sintering in CO2+air causes a detrimental effect on the grain boundary conductivity and therefore, on the total electrical conductivity of YSZ. It can be due to the presence of impurities such as carbonates and oxidised or even, polymerised carbonaceous species located at those areas. (C)2022 The Author(s). Published by Elsevier B.V. CC_BY_4.0

关键词： UV irradiation   Superhydrophobicity   Acetylated wood   Surface modification   Lignin degradation   Wettability  

摘要： The effect of prolonged ultraviolet (UV) irradiation on the performance of superhydrophobized birch and acetylated birch wood was investigated. The surface modification of the wood was based on a newly developed method using silicone nanofilaments. The combination of surface modification and acetylation of wood showed good wetting resistance also after 600 h of UV exposure, with water contact angles greater than 140 degrees and water uptake 30 times lower by weight than that of the non-surface-modified wood as determined by multicycle Wilhelmy plate measurements. Scanning electron microscopy images revealed that the silicone nanofilaments can still be observed on the wood samples after UV irradiation. The surface-modified wood samples exhibited significant color change after UV exposure. FTIR spectra showed that lignin was degraded on both the nonsurface-modified wood surfaces and the wood surface-modified with the silicone nanofilaments.