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The diffusion coefficients of simple chain models are analyzed as a function of packing fraction, η, and as a function of a parameter C that is the density raised to a power divided by temperature to look at scalar metrics to find master curves. The central feature in the analysis is the mapping onto an effective hard site diameter, d. For the molecular models lacking restrictions on dihedral angle (e.g., freely jointed), simple mappings of molecular potential to d work very well, and the reduced diffusion coefficient, D*, collapses into a single-valued function of η. Although this does not work for the dihedral angle restriction case, assuming that d is inversely proportional to temperature to a power results in collapse behavior for an empirically selected value of the power. This is equivalent to D* being a single-valued function of C. The diffusion coefficient of a single-site penetrant in the chain systems also is found to be a scalar metric that can reduce the chain diffusion data for a given system to a single master curve.
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http://dx.doi.org/10.1063/1.4851437 | DOI Listing |
Small
September 2025
State Key Laboratory of Functional Materials and Devices for Special Environments Conditions, Xinjiang Key Laboratory of Electronic Information Materials and Devices, Xinjiang Technical Institute of Physics and Chemistry of CAS, Urumqi, 830011, P. R. China.
Owing to its wide bandgap, LaAlO has garnered extensive attention in the field of high-temperature negative temperature coefficient (NTC) thermistors. However, its poor thermal stability and excessively high B value limit the working temperature range. In this work, introducing O 2p and Ni 3d hybrid energy levels into the bandgap is proposed via Ni doping and inducing stacking faults in the crystal structure to narrow the bandgap and enhance aging performance.
View Article and Find Full Text PDFFront Oncol
August 2025
Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
Background: Low-grade endometrial stromal sarcoma (LG-ESS) is a rare malignant tumor of the female reproductive system with atypical clinical symptoms and slow progression.
Case: A 44-year-old female with a history of intermittent severe dysmenorrhea, previous laparoscopic myomectomy, and uterine artery embolization (UAE) presented with rapidly enlarging pelvic masses. Imaging revealed uterine masses suggestive of leiomyomas, although an adnexal origin could not be excluded.
Chem Commun (Camb)
September 2025
School of Chemistry and Life Resources, Renmin University of China, Beijing, 100872, China.
Through molecular dynamics simulations of imidazolium-based ionic liquid-water mixtures, it was found that the trace water leads to an anomalous non-monotonic change in the diffusion coefficients of ionic liquid, characterized by an initial decrease followed by an increase. Hydrogen bond analysis revealed that this unusual trend is governed by the weighted hydrogen bond lifetime, reflecting the stability of the hydrogen-bond network, rather than simply the number or energy of hydrogen bonds.
View Article and Find Full Text PDFUltrason Sonochem
September 2025
College of Science, Inner Mongolia University of Technology, Hohhot 010051, China.
In this study, the systematic investigation focused on how varying power levels of ultrasonic (US) pretreatment, when integrated with electrohydrodynamic (EHD) drying, influence the physicochemical properties of yam. Yam samples were subjected to ultrasonic pretreatment at 30 °C for 30 min using power levels of 0 W (Control), 150 W, 180 W, 210 W, 240 W, and 270 W, respectively, followed by drying in an EHD system. During the drying process, a range of metrics were measured, including moisture content, average drying rate, color change, as well as rehydration capacity.
View Article and Find Full Text PDFChemosphere
September 2025
UMR Epoc 5805, Bordeaux-INP. 1 Allée Daguin, 33607, Pessac cedex, France. Electronic address:
In order to validate some assumptions and calculations of Johnson and Ettinger's model, a mapping of measured VOC fluxes in a heavily contaminated building was undertaken. To this end, both advective and diffusive flux measurements were carried out under real conditions. Diffusive fluxes were measured with flux chambers recording the initial concentration rise during the first minutes.
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