In this study, Acid Orange 7 azo dye was degraded on TiO2 catalyst layer illuminated with ultra-violet light. The TiO2 suspension had prior been sonicated at 20 kHz before electrophoretic deposition on smooth stainless steel surfaces, with the aim of increasing the efficiency of azo dyes degradation. The effect of sonication on the TiO2 suspension of 10 g.L-1 and electrophoretic deposition loading to layers on surfaces was studied. Morphological properties of the electrophoretic layers from two different suspensions, Alpha and Sigma TiO2 were characterized by Scanning Electron Microscopy to establish the specific surface properties, particle loading and crystalline sizes. A four–position reactor was used for dye degradation experiments under Ultra Violet light at 355 nm wavelength. The degradation of the azo dye was monitored at 30minutes interval for a total of 2 hours using Ultra Violet-Visible Spectrophotometer at λ = 485 nm. It was found out that 60% of dye degradation was achieved after 120 minutes without sonication pretreatment. Sonication pre-treatment resulted in 71.42% increase on the rate of photo-degradation, at a loading of 0.32 mg/cm2. Particulate layers coated with Alpha TiO2 showed more photoactivity compared to Sigma TiO2. Scanning Electron Microscopy indicated that Alpha TiO2 had  50 m2/g surface area and  28 nm crystal size compared to Sigma TiO2 with 10 m2/g and 169 nm crystal size. This study shows that sonication pretreatment of Alpha TiO2 /UV light system is most effective in photo-degrading Acid Orange 7 dye.

Advanced Oxidation Processes (AOPs) techniques are dependent on production of powerful oxidizing species that effectively treat wastewater (Fujishima and Rao, 1997; Ajmalet al., 2014; Al Rasheed and Cardin, 2003). Advanced Oxidation Processes (AOPs) as a novel technique has been used to eliminate organic contaminants in wastewater (Bergaminiet al., 2009). Photocatalysis as a novel wastewater treatment technique involves a light induced process that results in the oxidation of organic compounds by oxidation-reduction reactions activated by electron-hole pairs that form on the surface of powder catalysts i.e. semi-conductors (Chen et al., 2011). The subsequent generation of hydroxyl radicals (•OH), which are powerful oxidation species (2.8V vs. SHE) leads to non-selective reaction with the majority of electronrich sites of organic pollutants. With Ultra Violet (UV) light irradiation and appropriate photocatalyst, electron/hole pairs with free electrons are produced in the unfilled conduction band, leaving positively charged holes in the valence band (Wojnarovits and Takacs, 2008). These electron/hole pairs initiate a chain of chemical reactions that mineralize organic contaminants into CO2 and H2O. This process involves the cleavage of the conjugated carbon-carbon double bonds found in polyphenols by (•OH) radicals that causes decolourization of coloured wastewater and mineralization to CO2 and H2O (Chong et al., 2010; Gogate and Pandit, 2004). The process gradually degrades organic contaminants and prevents formation of sludge and secondary pollution. Suitable powder photocatalyst including TiO2 act as semi-conductor photocatalysts to degrade organic and inorganic pollutants into CO2 and H2O (Cernigoj, 2007; Bizaniet al., 2006) readily eliminating from wastewater all organic contaminants. Practical applications in slurry type suspensions are limited due to draw-backs caused by catalyst separation after photocatalytic treatment (Cernigoj, 2007). Photocatalytic Degradation MechanismThe photogenerated holes formed after the excitation of electrons from the valence band to conduction band exhibit strong oxidizing potential. The excited electrons are scavenged by oxygen and reduced to form superoxides from Dioxygen (Fujishimaet al., 2000; Fujishima and Rao, 1997). Fujishimaet al., (2000) described the 'Honda-Fujishima effect' that involved the photochemical splitting of H2O into H2 and O2 using titanium dioxide semi-conductor photocatalyst.

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This work examined the integral role of 'nonacademic stakeholders' in fostering the overall performance of students in primary and secondary schools in Kenya. School teachers are generally regarded by the Kenyan public as the 'sole custodians' of student performance in all assignments both curricular and extracurricular. On the contrary the progressive education of a learner from nursery to secondary school is evidently a 'wholesome' and 'holistic 'contribution from various stakeholders that comprises majorly; teachers, parents, and guardians. However nonacademic stakeholders that include subordinate staff, religious sponsors, old boy/girl alumni associations, health providers, Boards of Management (BOMs), Teachers Service Commission (TSC) and safety and security providers make equal significant contribution towards the eventual success of their students. In order to determine the extent of the role performed by nonacademic stakeholders 206 student respondents from a tertiary institution in Kenya were identified through a stratified random sampling technique and interviewed. The results obtained were presented using frequencies, graphs and pie-charts. The respondents reported the significant role of the nonacademic stakeholders as follows :-[( 86%, 178 students -important; 11%, 22 students -less important; 3%,6 students -not sure)].Individually the respondents ranked the following nonacademic stakeholders in order of significance; [( 14%, religious school sponsors; 8%, subordinate staff; 36%, parents; 6%, safety and security providers; 8%, old boy/girl alumni associations; 9%, Boards of Management (BOM); 6%, health providers; 13% Teachers Service Commission (TSC))].The present study concluded that overall performance in curricular and extracurricular assignments among students in Kenyan primary and secondary schools is influenced by multiple stakeholders in the education sector i.e. academic and nonacademic. The results show that 97% of all respondents viewed positively the role played by nonacademic stakeholders in promoting the overall performance of students in curricular and extracurricular assignments in primary and secondary schools in Kenya.