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In this study, polyvinyl alcohol (PVA) and titania (TiO2) Degussa P-25 were mixed to generate TiO2nonwoven filters using electrospinning. The wires of titanium dioxide and the nonwoven binding titania nanofibers were formed using 14 kV voltage and a distance of 15 cm. A single-factor experimental method was used to investigate the effects of parameters such as initial concentration, retention time, and light source on acetone removal by nonwoven binding titania nanofibers. Furthermore, the effects of parameters such as gas pressure, particle size, initial concentration, and retention time on the removal of particulates were also assessed. The results showed that the degradation efficiency increased with decreasing initial concentrations and increasing retention time. The best operational conditions during this study for the removal of acetone using the TiO2nonwoven filters were a retention time of 100 sec, initial acetone concentration of 250 ppm, and ultraviolet (UV) light source of 254 nm. Under those conditions, 99% acetone removal efficiency was obtained. In addition, 90% particulate matter removal efficiency was reached when the particulate size was greater than 200 nm and the reaction time was longer than 5 minutes. The prepared TiO2/nanofiber has good performance for volatile organic compounds (VOCs) and particulate removal at the same time. Implications:In this study, polyvinyl alcohol (PVA) and titania (TiO2) Degussa P-25 were mixed to generate TiO2 nonwoven filters using electrospinning. The results showed that the optimum operating conditions for the removal of acetone using the TiO2 nonwoven filters were a retention time of 100 sec, initial acetone concentration of 250 ppm, and UV light source of 254 nm. Under those conditions, 99% acetone removal efficiency was obtained. [ABSTRACT FROM AUTHOR]

Various versions of the Soave–Redlich–Kwong(SRK)equation of state incorporating different mixing rules were appliedto calculate vapor–liquid equilibrium (VLE), liquid–liquidequilibrium (LLE), and vapor–liquid–liquid equilibrium(VLLE) properties for the systems containing water, alcohols, andesters. The calculated results showed that the SRK equation with theT-type α function and the Chung–Twu (CT) mixing rulesembedded in the UNIFAC–Lyngby model (SRK-T/CT–UNIFAC–Lyngby) not only predicts accurately the VLE properties of the constituentbinaries but also represents the ternary LLE and VLLE phase behaviorreasonably well. Using this model, the vapor pressure data of thepure constituent components are the only required property for thephase equilibrium calculations. [ABSTRACT FROM AUTHOR]

Abstract: The enhancement of phase splitting was investigated for the liquid mixtures of water+ethanol+ethyl acetate in the presence of a hydrophilic agent (glycerol) or an electrolyte compound (potassium acetate, KAc, or calcium chloride, CaCl2). The liquid–liquid equilibrium (LLE) properties were measured for ternary systems of water+ethanol+ethyl acetate and water+ethyl acetate+CaCl2, and three quaternary systems, including water+ethanol+ethyl acetate+auxiliary agent (glycerol, potassium acetate, or calcium chloride), at temperatures ranging from 283.15K to 313.15K. The region of heterogeneity was found to increase as one of the auxiliary agents was introduced into the aqueous mixtures. By adding the same percentage of auxiliary agents, the magnitudes of phase-splitting enhancement follow the order of CaCl2 >KAc>glycerol. The Electrolyte-NRTL model was used to correlate the new LLE data for the investigated mixtures. In general, the model reproduces reasonably for the LLE phase envelops. [Copyright &y& Elsevier]

Although zinc oxide nanoparticles (ZnONPs) are recognized to cause systemic disorders, little is known about the mechanisms that underlie the time-dependent differences that occur after exposure. The objective of this study was to investigate the mechanistic differences at 24 hours and 28 days after the exposure of BALB/c mice to ZnONPs via intratracheal instillation. An isobaric tag for the relative and absolute quantitation coupled with liquid chromatography/tandem mass spectrometry was used to identify the differential protein expression, biological processes, molecular functions, and pathways. A total of 18 and 14 proteins displayed significant changes in the lung tissues at 24 hours and 28 days after exposure, respectively, with the most striking changes being observed for S100-A9 protein. Metabolic processes and catalytic activity were the main biological processes and molecular functions, respectively, in the responses at the 24-hour and 28-day follow-up times. The glycolysis/gluconeogenesis pathway was continuously downregulated from 24 hours to 28 days, whereas detoxification pathways were activated at the 28-day time-point after exposure. A comprehensive understanding of the potential time-dependent effects of exposure to ZnONPs was provided, which highlights the metabolic mechanisms that may be important in the responses to ZnONP.