Low Temperature Electrochemical Deposition of Highly Active Elements

Electrochemical methods are attractive for thin film deposition due to their simplicity, conformal and high rate deposition, the ability to easily make multilayers of different composition, ease of scale-up to large surface areas, and applicability to wide variety of different shapes and surface geometries. However, many elements from periodic table of commercial importance are too active to be electrodeposited from aqueous solution. Recent advances are briefly reviewed for room temperature methods for electrochemical deposition, including electrodeposition from ionic liquids, electrodeposition from organic solvents, combined electrodeposition and precipitation on liquid metal cathodes, and galvanic deposition. Recent studies of electrodeposition from ionic liquids include deposition of thick (40 µm) Al coatings on high-strength steel screws in a manufacturing environment; deposition of continuous Si, Ta and Nb coatings; and numerous interesting mechanistic studies. Recent studies of electrodeposition from organic solvents include Al coatings from the AlCl3-dimethylsulfone electrolyte, which demonstrate that additives can be employed to suppress impurity incorporation and to improve the deposit quality, and thick (5-7 µm) and continuous Si coatings from SiCl4 in acetonitrile. Galvanic deposition of Ti, Mo and Si coatings onto Al alloys has recently been reported, which is potentially much simpler and less expensive than electrodeposition from ionic liquids and organic solvents, but has complications associated with substrate consumption and coating adhesion

Impedance Biosensor Utilizing a Si Substrate Deposited by Wet Methods

We report an impedance biosensor utilizing a Si electrode created by wet chemical deposition atop 6061 Al alloy. The sensor electrode is created by galvanic/electroless Si deposition from an electrolyte containing 10 mM HF and 20 mM Na2SiF6 in 80 wt% formic acid, followed by antibody immobilization. The impedance response of the sensor electrode to increasing concentrations of peanut protein Ara h 1, a common food allergen, can be fit to an equivalent circuit containing three RC loops. The circuit element most sensitive to antigen binding is the charge transfer resistance, yielding a detection limit of 4 ng/mL

Electrodeposition of MoS2 for Charge Storage in Electrochemical Supercapacitors

Mo sulfide thin films were cathodically electrodeposited onto glassy carbon electrodes (GCE) from aqueous electrolytes containing 10 mM (NH4)2MoS4 and 0.2 M KCl. Film adhesion was adequate only for electrodes pretreated by potential cycling in 1.0 M HNO3 and 0.1 M NaF to enhance the surface roughness and partially oxidize the GCE. Previous studies report direct cathodic electrodeposition of MoS2, but energy dispersive x-ray spectroscopy and x-ray diffraction suggest that the as-deposited film is closer in stoichiometry to MoS3, which can be converted to MoS2 by annealing in Ar at 600°C for one hour. The charge storage capability of electrodeposited Mo sulfide films is studied here for the first time in 1.0 M Na2SO4 over the thickness range 50 nm to 5 µm, and before and after high temperature annealing. The highest capacitance is obtained for 50 nm thick MoS2 films is 330 F/g measured by galvanostatic charge discharge at 0.75 A/g, and 360 F/g measured by cyclic voltammetry at 10 mV/sec. The capacitance per unit mass decreases with increasing film thickness due to reduced electrochemical accessibility. MoS2 film formed by high temperature annealing in Ar have a charge storage capability about 40x higher than the as-deposited Mo sulfide films

STRATEGIC PEOPLE MANAGEMENT SKILL DIMENSIONS IN BUILDING SUSTAINABLE COMPETITIVE ADVANTAGE OF CHRISTIAN FAITH-BASED ORGANISATIONS IN NIGERIA: A CONCEPTUAL REVIEW

Purpose/Aim In order to build principles in the organisational workforce and environment, strategic people management skills include articulating the selection of skills, expertise, competencies and personal qualities. This paper aims to explore how the implementation of strategic people management skills serves as a driver to sustainable competitive advantage in the competitive religious environment by utilizing the Christian Faith-Based Organisations in Nigeria. Research Methodology A conceptual approach based on the analysis of historical trends in the implementation of people management skills, especially among Christian Faith-based organisations in Nigeria, based on current literature. Key factors necessary for the satisfactory implementation of strategic people management skills were identified which include training and re-training, career development and motivational factors. Research Findings Findings from extant literature show that beyond the operational strategic purview of Nigerian Christian Faith- Based Organisations, other critical factors such as environmental influence create a significant link between people management skills and the level of compliance from affected parties. This also partly determines the amount of resource requirement to support the implementation of people management projects. In terms of the aspirations of Christian Faith-Based Organisational leaders in Nigeria, environmental variables play a key role. Conclusion and Recommendations Based on these findings, we recommend that leaders should endeavour to define directional policy that enhances people management skills and establish measurable goals to meet members of staff, members and followers’ expectations and to improve on organisational competitive advantage. Future research could be focused on empirical studies of Christian faith-based organisation in this direction. Keywords: Christian Faith-Based Organisations, Strategic People Management Skills, Sustainable Competitive Advantage

ESPOUSING THE DETERMINANTS OF ACADEMIC STAFF RETENTION PRACTICES IN THE PUBLIC UNIVERSITIES

In the globalized knowledge-based economy, retention is recognized as the key element for competitiveness and economic growth. In the University system, retention practices have played a substantial role in nation-building and economic affluence. The early decades of the Nigerian university system were characterised by impressive achievements. Today, Universities in Nigeria are subdued by limited access to resources, inadequacies in facilities for teaching, learning and research; inadequate funding; deficits in teacher quality and quantity (including quality of professors); governance deficits (including stemming the tide of strikes); depressed quality of graduates; inadequacies in access; deficiencies in research and postgraduate training; academic corruption and other social vices. Hence, this study examines the determinant of academic staff retention practices in the Nigerian University system. Articles indexed in Google scholar, NUC, EBSCO, Science direct, Sage, Elsevier and Scopus database were reviewed. The underlying theories adopted for this study were Expectancy theory, Fredrick Herzberg Two-factor theory and Job embeddedness Theory. The study concludes that we need as a nation (Nigeria) to adopt the UNESCO recommendation on spending 25% GDP on Education. This study recommends that increased academic staff retention can be achieved through the implementation of systemic regulatory functions by NUC and professional bodies, promotion of ICT-driven universities, fostering skills development and entrepreneurship, and gender issues

Moving boundary models for the growth of crystalline deposits from undetected leakages of industrial process liquors

In this study, a computational model which simulates the growth of crystalline deposits from dripping salt solution is developed and validated. This problem is of interest to the nuclear industry where the morphology of deposited material impacts on its associated criticality risk. An existing model for simulating geological-stalagmite formations is adapted to the case of dripping salt-solutions which form thin films of fluid that precipitate out over time, forming accumulations. The implementation of a CFD Volume-of-Fluid multiphase model is developed such that the fluid-flow is coupled to the crystallisation kinetics and a moving-boundary model is used for describing the size and shape of growing crystalline deposits. The fluid-flow and forming accumulation are fully coupled, with the model able to account for solute diffusion and solvent evaporation. Results are in good agreement with experimental data for surrogate salt-solutions. Numerical results are presented to assess the sensitivity to process and environmental parameters

High-depth African genomes inform human migration and health.

The African continent is regarded as the cradle of modern humans and African genomes contain more genetic variation than those from any other continent, yet only a fraction of the genetic diversity among African individuals has been surveyed1. Here we performed whole-genome sequencing analyses of 426 individuals-comprising 50 ethnolinguistic groups, including previously unsampled populations-to explore the breadth of genomic diversity across Africa. We uncovered more than 3 million previously undescribed variants, most of which were found among individuals from newly sampled ethnolinguistic groups, as well as 62 previously unreported loci that are under strong selection, which were predominantly found in genes that are involved in viral immunity, DNA repair and metabolism. We observed complex patterns of ancestral admixture and putative-damaging and novel variation, both within and between populations, alongside evidence that Zambia was a likely intermediate site along the routes of expansion of Bantu-speaking populations. Pathogenic variants in genes that are currently characterized as medically relevant were uncommon-but in other genes, variants denoted as 'likely pathogenic' in the ClinVar database were commonly observed. Collectively, these findings refine our current understanding of continental migration, identify gene flow and the response to human disease as strong drivers of genome-level population variation, and underscore the scientific imperative for a broader characterization of the genomic diversity of African individuals to understand human ancestry and improve health