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The COVID-19 pandemic has deeply impacted patient and family communication and patient- and family-centred care in the intensive care unit (ICU). A new role—the ICU Family Liaison Nurse (FLN)—was introduced in an Australian metropolitan hospital ICU to facilitate communication between patient and family and ICU healthcare professionals, although there is limited knowledge about the impact of this from the ICU healthcare professionals' perspectives.

The capture and separation properties of surface-functionalized activated carbons (AC–Rs, R= −COOH, −OH, −NH2, and −SO3H) for the methanol–acetone mixture were investigated for the first time by grand canonical Monte Carlo simulation (GCMC) and density functional theory (DFT). The effects of surface functional groups and structural characteristics of AC–Rs on the adsorption and separation behaviors of methanol and acetone were clarified. The surface functional group with strong electron-donating or electron-accepting capacity (i.e., −NH2, −OH, and −SO3H) was a crucial factor for the methanol–acetone capture and separation performance at the lower pressure range, and the accessible surface area was found to be another determinative factor. AC–NH2with the relatively large accessible surface area (4497 m2/g) exhibited an efficient capture performance for the single component (15.7 mol/kg for methanol and 6.7 mol/kg for acetone) and the highest methanol/acetone selectivity (∼23) at 0.02 kPa. At high pressures, the surface functionalization and available pore volume of AC–Rs played pivotal roles in the adsorptive separation process. This study provided mechanistic insights on how the surface functional groups affected the capture and separation properties of ACs, which would further provide a rational alternative strategy in the preparation and synthesis of ACs for the effective gas mixture separation.

ABSTRACTActivated carbons were prepared from tobacco stem by chemical activation using potassium hydroxide (KOH), potassium carbonate (K2CO3), and zinc chloride (ZnCl2). The effects of the impregnation ratio (activating agent/precursor) and activating agents on the physical and chemical properties of activated carbons were investigated. The textual structure and surface properties of activated carbons were characterized by nitrogen (N2) adsorption isotherm, scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), x-ray photoelectron spectroscopy (XPS), and thermogravimetry (TG). ZnCl2, acting as a superior activating agent compared to the others, produced much more porosity. The maximum specific surface area reached 1347 m2/g, obtained by ZnCl2activation with an impregnation ratio of 4.0. Moreover, ZnCl2activation yielded products with an excellent thermostability, attributed to different activation mechanisms. Various oxygen functions were detected on the activated carbon surface, and hydroxyl and ester groups were found to be in the majority.Implications: Tobacco stem, the residue from cigarette manufacturing, is usually discarded as waste, leading to serious resource waste and environmental problems. This study provides an effective utilization available for this solid residue by using it as the starting material in the preparation of activated carbon with chemical activation. Activated carbons with high specific area and various surface functions have been prepared, and the effects of the amount and type of activating agents on the physical and chemical properties of activated carbon were investigated as well.

Commercial activated carbon (AC) was modified using formic acid, oxalic acid, and sulfamic acid separately. The effects of the modification on the physicochemical properties of ACs were evaluated using specific surface area and pore distribution, scanning electron microscope, and Fourier transform infrared spectroscopy. After the modification, (i) the BET specific surface area and total pore volume of ACs decreased, (ii) uneven etching trace and white crystal particles were observed on the surface of AC, and (iii) more oxygen-containing functional groups such as OH, CO, CO, and SO were formed on the surface. The effects of the modifications on the adsorption behavior of acetone and isopropanol on ACs at different inlet concentrations were studied from adsorption equilibrium, kinetics, and energy point of view. The results show that the equilibrium adsorption capacity has been greatly improved by the modification of organic acids. The adsorption isotherms of acetone and isopropanol on ACs are well fitted by both Langmuir and Freundlich equations. Characteristic adsorption energy values of acetone and isopropanol slightly increase with increasing of oxygen functional groups on the ACs surface. The adsorption kinetics of acetone and isopropanol on ACs are best described by Bangham kinetics model.