Comprehensive analysis of the structure and phase behavior for a number of 2,3,4-tris(dodecyloxy)benzenesulfonates with alkali metal and organic focal groups revealed that the shape of the mesogenic group plays a decisive role in phase behavior of the material. Cubic and layered types of packing prevail when the size of the cation is small and, thus, the shape of the mesogenic molecule is close to conic one. With increasing cation size, the shape becomes more tapered, and columnar mesophases appear to be more stable. Interactions of the focal groups however determine the stability of mesophases. Comparatively strong interactions may, morever, provide substantial deviations from a phase diagram plotting the transition temperatures versus the radius of focal group, as in the case of pyridinium 2,3,4-tris(dodecyloxy)benzenesulfonate.
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http://dx.doi.org/10.1039/c7cc04807f | DOI Listing |
BMC Chem
January 2025
Nuclear Chemistry Department, Hot Laboratories Center, Egyptian Atomic Energy Authority, P.O. 13759, Cairo, Egypt.
In this work, selenium (IV) ions were adsorbed from aqueous solutions by the strongly basic anion exchange resin Amberlite IRA-400. The morphology of the resin before and after Se(IV) sorption was investigated using different techniques such as energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). To determine the ideal sorption conditions, a batch approach was used to examine the variables affecting Se(IV) sorption performance, including pH, shaking time, adsorbent dosage, initial metal ion concentration, and temperature.
View Article and Find Full Text PDFBMC Public Health
January 2025
School of Psychology, Guizhou Normal University, Guizhou, China.
Background: Functional Gastrointestinal Disorders (FGIDs) constitute a group of psychosomatic diseases characterized primarily by disruptions in the functioning of the digestive system, profoundly impacting the lives of affected individuals.
Objective: This study aims to investigate the influence of negative affect (NA) on the gastrointestinal symptoms of FGID patients, as well as the mediating role of rumination and the regulatory effects of expression suppression (ES) as an emotional regulation strategy.
Methods: A survey was conducted on 1000 patients (403M, 597F) with gastrointestinal disorders at a tertiary hospital using the negative affect subscale from the DS-14 (Type D Personality Scale), the Gastrointestinal Symptom Rating Scale (GSRS), the Rumination Response Scale (RRS), and the expression suppression subscale from the Gross-John Emotion Regulation Strategy.
Sci Rep
January 2025
Chengfa Urban Service Technology (Henan) Co., Ltd, Zhengzhou, 450002, People's Republic of China.
In order to study the change rule of freshness and acid ions in reconstituted tobacco slurry, the content changes of 17 organic acids and 5 inorganic anions in reconstituted tobacco slurry with different residence times under confined condition were determined by on-line solid-phase extraction ion chromatography in this study. The results showed that the changes of acetic acid, nitrate ion and isovaleric acid in different reconstituted tobacco slurries with oscillation time were regular and consistent, and the trends of the changes of acetic acid, nitrate ion and isovaleric acid in different reconstituted tobacco slurries with oscillation time were correlated with each other in a highly significant way. Taking the evaluation of olfactory aroma and sensory quality qualities of reconstituted tobacco pulps with different residence times as a benchmark, it was found that the variation patterns of nitrate ions and isovaleric acid in reconstituted tobacco pulps with oscillation time were consistent with the variation patterns of olfactory and sensory qualities in the process of closed oscillation; compared with the fresh pulp, the olfactory aroma and sensory qualities of tobacco pulps had unpleasant odours appearing when the content of nitrate ions was reduced by about 48%.
View Article and Find Full Text PDFQuantifying cognitive potential relies on psychometric measures that do not directly reflect cortical activity. While the relationship between cognitive ability and resting state EEG signal dynamics has been extensively studied in children with below-average cognitive performances, there remains a paucity of research focusing on individuals with normal to above-average cognitive functioning. This study aimed to elucidate the resting EEG dynamics in children aged four to 12 years across normal to above-average cognitive potential.
View Article and Find Full Text PDFNat Commun
January 2025
Department of Chemistry, Columbia University, New York, NY, USA.
Among expanding discoveries of quantum phases in moiré superlattices, correlated insulators stand out as both the most stable and most commonly observed. Despite the central importance of these states in moiré physics, little is known about their underlying nature. Here, we use pump-probe spectroscopy to show distinct time-domain signatures of correlated insulators at fillings of one (ν = -1) and two (ν = -2) holes per moiré unit cell in the angle-aligned WSe/WS system.
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