Browsing Research Output by Title
Now showing items 2709-2728 of 13381
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Density functional theory calculation of Ti3C2 MXene monolayer as catalytic support for platinum towards the dehydrogenation of methylcyclohexane
(Elsevier, 2020)The need for sustainable energy systems and reducing greenhouse gas emissions are key drivers in the development of liquid hydrogen organic carriers (LOHCs). Density functional theory calculations were performed on the ... -
Density functional theory molecular modelling and experimental particle kinetics for CO2-char gasification
(Elsevier, 2015)Experimental measurements and DFT atomistic modelling were conducted to elucidate the mechanisms for gasification chemistry of char with CO2 gas. The molecular models used were based on experimental representations of coal ... -
Density functional theory prediction of the aqueous speciation of ZrF4 and HfF4
(SAIMM, 2018)Computational chemistry was used to make predictions regarding the stepwise hydrolysis and fluoride dissociation reactions of ZrF4 and HfF4 in aqueous solutions. Specifically, density functional theory was used to predict ... -
Density functional theory studies of the SrC and SrN compounds
(Elsevier, 2019)The structural, magnetic, elastic, dynamical and thermodynamic properties of the SrC and SrN compounds were studied using density functional theory. We found that the CsCl and NaCl phases have the lowest energy configurations ... -
Density functional theory study with and without COSMO of H2SO4 reactions in an aqueous environment for metal extraction
(Wiley, 2019)In a recent study investigating the suitability of solvent extraction (SX) for the separation of Ta and Nb, it was shown that speciation data would be required to help explain the data obtained. As traditional speciation ... -
Density-dependent growth response and sensitivity of Meloidogyne incognita to Maerua angolensis and Tabernaemontana elegans: Card model
(Taylor & Francis, 2019)Curve-fitting Allelochemical Response Dosage (CARD) computer-based model has proven to be a valuable tool in the definition of dosage response relationships between organisms and various plant extracts. Its use in the ... -
Density-dependent spatial patterning of woody plants differs between a semi-arid and a mesic savanna in South Africa
(Elsevier, 2018)Savannas can be defined by the co-dominance of grasses and trees. Interactions between these two life forms are relatively well studied, whereas tree-tree interactions attracted increased attention only recently. However, ... -
A density-functional theory approach to the separation of K2ZrF6 and K2HfF6 via fractional crystallization
(Wiley, 2011)Because of the low absorption cross-section for thermal neutrons of zirconium (Zr) as opposed to hafnium (Hf), Zr-metal must essentially be Hf-free (<100 ppm Hf) to be suitable for use in nuclear reactors. However, Zr and ... -
Dentalisation as regional indicator in general South African English: an acoustic analysis of /z/, /d/ and /t/
(Taylor & Francis, 2011)Drawing on Bekker's (2007) study on the dentalisation of /s/ among young middle-class females from Johannesburg, this research aims to test whether the other traditionally alveolar oral obstruents, namely /z/, /d/ and /t/, ... -
Dependence of cardiac systolic function on elevated fatty acid availability in obese, insulin-resistant rats
(Elsevier, 2016)Background Clinical data advocating an adverse effect of obesity on left ventricular (LV) systolic function independent of comorbidities is controversial. We hypothesized that in obesity with prediabetic insulin resistance, ... -
The dependence of optical polarisation of blazars on the synchrotron peak frequency
(PoS, 2017)The RoboPol instrument and the relevant program was developed in order to conduct a systematic study of the optical polarisation variability of blazars. Driven by the discovery that long smooth rotations of the optical ... -
Dependency on chloride concentration and ‘in-sphere’ oxidation of H2O for the effective TiO2-photocatalysed electron transfer from H2O to [PdCln(H2O)4−n]2−n (n = 0–4) in the absence of an added sacrificial reducing agent
(Elsevier, 2012)The photocatalytic reduction trends of palladium chloride aqua complexes, [PdCln(H2O)4−n]2−n (n = 0–4), have been investigated employing titanium dioxide (TiO2) as photocatalyst in the absence of an added sacrificial ... -
The depletion of narrative resources in the Kenyan trade union movement
(Virtus Interpress, 2015)We discuss in this study the problems of mobilization and effectiveness faced by Kenyan trade unions. In a country with high levels of unemployment and weak labour legislation, it is imperative that the labour movement ... -
Depressed, not depressed or unsure: prevalence and the relation to well–being across sectors in South Africa
(AOSIS, 2012)Orientation: Work engagement, burnout and stress-related ill health levels of individuals, suffering from depression, who are unsure whether or not they suffer from depression, or who do not suffer from depression, have ... -
Depression symptoms facilitated fibrinolytic dysregulation and future coronary artery disease risk in a black male cohort: the sympathetic activity and ambulatory blood pressure in Africans study
(Wolters Kluwer, 2017)Background: Hypercoagulation is associated with coronary artery disease (CAD). Whether depression symptoms dysregulate inflammatory and hemostatic markers in an African cohort is not known; therefore, we assessed the ... -
Depression, cardiometabolic function and left ventricular hypertrophy in African men and women: the SABPA study
(Taylor & Francis, 2013)Depressive symptoms are associated with an increased risk for developing cardiovascular diseases, driven by its link to the metabolic syndrome (MetS). This phenomenon, however, still needs to be investigated in the African ... -
Depressive symptoms and 24-hour ambulatory blood pressure in Africans: the SABPA study
(Hindawi, 2012)Disturbances in circadian rhythm might play a central role in the neurobiology of depression. We examined the association between depressive symptoms and 24-hour ambulatory BP in a sample of 405 (197 black and 208 Caucasian) ... -
Depressive symptoms and sub-clinical atherosclerosis in Africans: role of metabolic syndrome, inflammation and sympathoadrenal function
(Elsevier, 2011)Depressive symptoms have been consistently associated with sub-clinical atherosclerosis and future risk of coronary heart disease events. However, the pathways linking depression and coronary atherosclerosis are poorly ... -
Deriving an optimal threshold of waist circumference for detecting cardiometabolic risk in sub-Saharan Africa
(Nature, 2018)BACKGROUND: Waist circumference (WC) thresholds derived from western populations continue to be used in sub-Saharan Africa (SSA) despite increasing evidence of ethnic variation in the association between adiposity and ... -
Dermal exposure and changes in skin barrier function of base metal refinery workers co-exposed to cobalt and nickel
(The South African Society of Occupational Medicin, 2013)Refi nery workers are exposed to many metals, including cobalt and nickel, both of which are skin sensitisers, causing allergic contact dermatitis. Dermal exposure, and changes in skin barrier function [skin hydration, ...