排序方式: 共有44条查询结果,搜索用时 15 毫秒
41.
Marielle Soniat Meron Tesfaye Amirhossein Mafi Daniel J. Brooks Nicholas D. Humphrey Lien-Chun Weng Boris Merinov William A. Goddard III Adam Z. Weber Frances A. Houle 《Journal of polymer science. Part A, Polymer chemistry》2020,58(9):1207-1228
Glassy polymers are often used for gas separations because of their high selectivity. Although the dual-mode permeation model correctly fits their sorption and permeation isotherms, its physical interpretation is disputed, and it does not describe permeation far from steady state, a condition expected when separations involve intermittent renewable energy sources. To develop a more comprehensive permeation model, we combine experiment, molecular dynamics, and multiscale reaction–diffusion modeling to characterize the time-dependent permeation of N2 and CO2 through a glassy poly(dimethyl phenylene oxide) membrane, a model system. Simulations of experimental time-dependent permeation data for both gases in the presteady-state and steady-state regimes show that both single- and dual-mode reaction–diffusion models reproduce the experimental observations, and that sorbed gas concentrations lag the external pressure rise. The results point to environment-sensitive diffusion coefficients as a vital characteristic of transport in glassy polymers. 相似文献
42.
Bazargan Amirhossein Karray Salma Zolfaghari Saeed 《Computational Management Science》2021,18(1):99-124
Computational Management Science - This research investigates whether it is beneficial for competing firms offering loyalty programs (LPs) to restrict the reward redemption time. We develop a... 相似文献
43.
Amir Akbari Sarah Maghsoodi Amirhossein Shahbazi Kootenaei 《Journal of Dispersion Science and Technology》2019,40(1):17-24
This research aimed to evaluate the thermal viscosity, stability, conductivity and density of coolants including PEG-functionalized graphene nanoplatelets (GNPs) and gum Arabic (GA)-treated GNPs as a base fluid at various temperatures and concentrations. The present study explores the impacts of GNPs functionalized with poly ethylene glycol (PEG) on the colloidal stability and thermophysical properties of water-based PEG-functionalized GNPs suspensions as a new generation of heat transfer fluids. To this end, PEG-functionalized GNPs as a covalent sample and GA-treated GNPs were synthesized and their colloidal stabilities were traced via UV–vis spectrometry. After functionalized, colloidal stability results indicate less sedimentation for covalent samples (less than 10%) that that of noncovalent one (almost 20%) after a 15-day period. In addition, all the thermophysical properties e.g. thermal conductivity, density and viscosity were measured experimentally. Further, it has shown that by loading PEG-functionalized GNPs in the water, the increasing rate of the density and viscosity is not significant, while water-based GA-treated GNPs nanofluids showed higher rates of increase. Interestingly, the water-based PEG-functionalized GNP nanofluids at very low concentration significantly increase the thermal conductivity in comparison with that of non-covalent nanofluid at the same concentration and temperature and defiantly water. 相似文献
44.
Karimian Somaye Ranjbar Sara Dadfar Mahsa Khoshneviszadeh Mahsima Gholampour Maryam Sakhteman Amirhossein Khoshneviszadeh Mehdi 《Molecular diversity》2021,25(4):2339-2349
Molecular Diversity - A series of ethyl 2-amino-4H-benzo[h]chromene-3-carboxylate derivatives, having phenyl ring with diverse substituents at C4 position of 4H-benzochromene nucleus, were... 相似文献