Experimentally measured methane hydrate phase equilibria and ionic liquids inhibition performance in Qatar's seawater.

Qatar has the third-largest natural gas reserves in the world and is the second largest Liquefied natural gas (LNG) exporter in the world. These reserves are mainly located in its offshore North Field where the gas is extracted, transported to the onshore units, and is converted to LNG for international export. The formation of natural gas hydrates in the offshore subsea lines can cause unwanted blockages and hinder the smooth supply of gas supply from offshore to onshore units. In the present work, the formation and dissociation of methane gas hydrates have been studied in the ultra pure water system (UPW), artificial seawater (ASW), and Qatar seawater (QSW) at different conditions (4-10 MPa) using standard rocking cell rig. The naturally occurring seawater was collected from Ras Laffan seacoast located in Doha, Qatar. The seawater sample was examined for elemental analysis (SO4, Cl, Na, Ca, Mg, K, and Fe) using inductively coupled plasma atomic emission spectroscopy (ICP-AES) technique and its other properties like density, electrical conductivity, and pH were also measured. The experimental results show that the CH4 pure water HLVE curve is suppressed by about 3 K in Qatar seawater and 2 K in artificial seawater. The hydrate inhibition strength of the Ionic liquids (ILs) salts 3-Ethyl-1-methyl-1H-imidazol-3-ium methane-sulfonate [C7H14N2O3S] and 3-Ethyl-1-methyl-1H-imidazol-3-ium dicyanoazanide [C8H11N5] was evaluated in both the ultra pure water and Qatar seawater systems. Their performance was compared with methanol and other ILs salts reported in the literature. The selected ILs exhibited poor hydrate inhibition effect in the ultra pure water systems, but they show a noticeable thermodynamic and kinetic hydrate inhibition effect in the Qatar seawater system. The computational 3D molecular models of ILs and methanol were generated to cognize the plausible hydrate inhibition mechanism in the presence of these inhibitors.

Effects of an oral health promotion program in people with mental illness.

More knowledge is needed regarding what works to prevent oral health problems and reduce disparities in oral health. Motivational interviewing (MI) has demonstrated utility for improving health behavior, including among those with severe mental illness. This study tests whether MI enhances the efficacy of an oral health education intervention in individuals with severe mental illness. Sixty individuals were randomly assigned to MI plus oral health education or oral health education alone. Plaque scores, oral health knowledge, and self-regulation were assessed at baseline and at 4 and 8 weeks. Repeated-measures ANOVA showed improvement (p < 0.05) in plaque, autonomous regulation, and oral health knowledge across time for both groups; however, individuals receiving MI improved significantly more when compared with those receiving oral health education alone. Results suggest that MI is effective for enhancing short-term oral health behavior change for people with severe mental illness and may be useful for the general population.