This paper presented the preparation of TiO2 thin film on empty glass and Indium Tin Oxide (ITO) glass by spin coating method. Highly transparent titanium oxide thin films were obtained. The Optical absorption and tra...This paper presented the preparation of TiO2 thin film on empty glass and Indium Tin Oxide (ITO) glass by spin coating method. Highly transparent titanium oxide thin films were obtained. The Optical absorption and transmission of the film prepared from both the synthesized and the commercially available TiO2 were measured by the UV-Visible Spectrophotometer. A sharp absorption edge of the TiO2 film was observed. The estimated energy band gap for the film of the commercially available sample was larger than that of the synthesized one.展开更多
This work investigated the electrical properties of TiO2 thin film on empty glass and ITO glass by spin coating method. Highly transparent titanium oxide thin films were prepared on empty glass and Indium Tin Oxide (I...This work investigated the electrical properties of TiO2 thin film on empty glass and ITO glass by spin coating method. Highly transparent titanium oxide thin films were prepared on empty glass and Indium Tin Oxide (ITO) from a titanium (III) chloride precursor. The sheet resistance of the film prepared from both the synthesised and the commercially available TiO2 was measured by the Keithley four-point probe tester (KFPPT). A comparable sheet resistance of 10.69E + 00 Ω/sq was obtained on the ITO. The electrical conductivity of the TiO2 film on ITO glass substrate was found to be very high (3.46E + 05 Ω-1?cm-1) and comparable to that of the bare ITO glass.展开更多
This paper presents the report of corrosion prevention study carried out on plain carbon steel lined with calcite, magnesium carbonate and dolomite as coats. Eight samples each of the steel were dipped into solutions ...This paper presents the report of corrosion prevention study carried out on plain carbon steel lined with calcite, magnesium carbonate and dolomite as coats. Eight samples each of the steel were dipped into solutions of CaCO3, CaCO3 and MgCO3, and MgCO3. Pipe borne water obtained from Obafemi Awolowo University, Ile-Ife water works was used as the environment. The corroded sample surfaces were subject to microstructural characterization using optical microscopy technique. The results obtained showed that the steel exhibited minimum corrosion rate of less than 0.5 mm/yr in dolomite, followed by MgCO3 and then by CaCO3 with corrosion rate far above 0.5 mm/yr bench mark. The unlined (control) samples have maximum corrosion rate of 0.8 mm/yr. the microstructures revealed widespread localized attacks and to a uniform corrosion. The dolomite lined samples are recommended for corrosion prevention of plain carbon steel in pipe borne water.展开更多
Chemical mitigation is regularly used as one of the principal prevention and control techniques in reinforcement corrosion. Hence this study presents the effect of toluene and dioctylphthalate on the rebar corrosion o...Chemical mitigation is regularly used as one of the principal prevention and control techniques in reinforcement corrosion. Hence this study presents the effect of toluene and dioctylphthalate on the rebar corrosion of medium carbon steel in seawater and cassava fluid with a view to determining inhibitive potentials of the different inhibitors in the two media. Gravimetric and voltametric techniques were employed in this study and a total of forty-five corrosion coupons of different dimensions were produced. Forty coupons were used for gravimetry and the remaining five for corrosion potentials measurements. Eight of the samples were used as control;while other eight samples were admixed with dioctylphthalate and toluene in concrete cubes. It was later immersed in seawater and cassava fluid for a total duration of 32 days and the measurements were taken at interval of 4 days in order to determine the corrosion rates in mils per year (mmpy). Two controls and admixed samples were later immersed in seawater and cassava fluid, respectively, for durations of thirty-two days to determine the corrosion potentials using a voltmeter and a Copper-Copper Sulphate Electrode (Cu/CuSO4). The pH of each medium was also measured throughout the period of exposure. The results obtained showed that all the samples except the control samples, displayed some degree of inhibition. The inhibition levels for the admixed samples in seawater were on the higher side compared with those in cassava fluid. The inhibition efficiencies for different inhibitors followed different trends in different environment. The inhibition efficiencies for toluene in cassava fluid and seawater were 21.64% and 45.78% respectively. The study concluded that organic inhibitors were effective in inhibiting corrosion in cyanide and chloride contaminated concrete cubes.展开更多
Inhibitors are regularly used as one of the principal prevention and control techniques in reinforcement corrosion. Hence this study investigates the effect of calcium nitrate and sodium nitrite inhibitors on the reba...Inhibitors are regularly used as one of the principal prevention and control techniques in reinforcement corrosion. Hence this study investigates the effect of calcium nitrate and sodium nitrite inhibitors on the rebar corrosion of medium carbon steel in seawater and cassava fluid with a view to determining inhibitive potentials of the different inhibitors in the two media. Gravimetric and voltametric techniques were employed in this study and a total of forty-five corrosion coupons of different dimensions were produced. Forty coupons were used for gravimetric analysis and the remaining five for corrosion potentials measurements. Eight of the samples were used as control;while other eight samples each were admixed with calcium nitrate and sodium nitrite in concrete cubes. It was later immersed in seawater and cassava fluid for a total duration of 32 days and the measurements were taken at the interval of 4 days in order to determine the corrosion rates in mils per year (mmpy). Two controls and admixed samples each were later immersed in seawater and cassava fluid, respectively, for durations of 32 days to determine the corrosion potentials using a voltmeter and a Copper-Copper Sulphate Electrode (Cu/CuSO4). The pH of each medium was measured throughout the period of exposure. The results obtained expressed that all the samples except the control samples, displayed some degree of inhibition. The inhibition levels for the admixed samples in seawater were higher compared with those in cassava fluid. Inhibition efficiencies for various inhibitors followed different trends in different environment. The inhibition efficiencies for calcium nitrate in cassava fluid and seawater were 26.81% and 64.85% respectively. The study concluded that inorganic inhibitors were effective in inhibiting corrosion in cyanide and chloride contaminated concrete cubes.展开更多
文摘This paper presented the preparation of TiO2 thin film on empty glass and Indium Tin Oxide (ITO) glass by spin coating method. Highly transparent titanium oxide thin films were obtained. The Optical absorption and transmission of the film prepared from both the synthesized and the commercially available TiO2 were measured by the UV-Visible Spectrophotometer. A sharp absorption edge of the TiO2 film was observed. The estimated energy band gap for the film of the commercially available sample was larger than that of the synthesized one.
文摘This work investigated the electrical properties of TiO2 thin film on empty glass and ITO glass by spin coating method. Highly transparent titanium oxide thin films were prepared on empty glass and Indium Tin Oxide (ITO) from a titanium (III) chloride precursor. The sheet resistance of the film prepared from both the synthesised and the commercially available TiO2 was measured by the Keithley four-point probe tester (KFPPT). A comparable sheet resistance of 10.69E + 00 Ω/sq was obtained on the ITO. The electrical conductivity of the TiO2 film on ITO glass substrate was found to be very high (3.46E + 05 Ω-1?cm-1) and comparable to that of the bare ITO glass.
文摘This paper presents the report of corrosion prevention study carried out on plain carbon steel lined with calcite, magnesium carbonate and dolomite as coats. Eight samples each of the steel were dipped into solutions of CaCO3, CaCO3 and MgCO3, and MgCO3. Pipe borne water obtained from Obafemi Awolowo University, Ile-Ife water works was used as the environment. The corroded sample surfaces were subject to microstructural characterization using optical microscopy technique. The results obtained showed that the steel exhibited minimum corrosion rate of less than 0.5 mm/yr in dolomite, followed by MgCO3 and then by CaCO3 with corrosion rate far above 0.5 mm/yr bench mark. The unlined (control) samples have maximum corrosion rate of 0.8 mm/yr. the microstructures revealed widespread localized attacks and to a uniform corrosion. The dolomite lined samples are recommended for corrosion prevention of plain carbon steel in pipe borne water.
文摘Chemical mitigation is regularly used as one of the principal prevention and control techniques in reinforcement corrosion. Hence this study presents the effect of toluene and dioctylphthalate on the rebar corrosion of medium carbon steel in seawater and cassava fluid with a view to determining inhibitive potentials of the different inhibitors in the two media. Gravimetric and voltametric techniques were employed in this study and a total of forty-five corrosion coupons of different dimensions were produced. Forty coupons were used for gravimetry and the remaining five for corrosion potentials measurements. Eight of the samples were used as control;while other eight samples were admixed with dioctylphthalate and toluene in concrete cubes. It was later immersed in seawater and cassava fluid for a total duration of 32 days and the measurements were taken at interval of 4 days in order to determine the corrosion rates in mils per year (mmpy). Two controls and admixed samples were later immersed in seawater and cassava fluid, respectively, for durations of thirty-two days to determine the corrosion potentials using a voltmeter and a Copper-Copper Sulphate Electrode (Cu/CuSO4). The pH of each medium was also measured throughout the period of exposure. The results obtained showed that all the samples except the control samples, displayed some degree of inhibition. The inhibition levels for the admixed samples in seawater were on the higher side compared with those in cassava fluid. The inhibition efficiencies for different inhibitors followed different trends in different environment. The inhibition efficiencies for toluene in cassava fluid and seawater were 21.64% and 45.78% respectively. The study concluded that organic inhibitors were effective in inhibiting corrosion in cyanide and chloride contaminated concrete cubes.
文摘Inhibitors are regularly used as one of the principal prevention and control techniques in reinforcement corrosion. Hence this study investigates the effect of calcium nitrate and sodium nitrite inhibitors on the rebar corrosion of medium carbon steel in seawater and cassava fluid with a view to determining inhibitive potentials of the different inhibitors in the two media. Gravimetric and voltametric techniques were employed in this study and a total of forty-five corrosion coupons of different dimensions were produced. Forty coupons were used for gravimetric analysis and the remaining five for corrosion potentials measurements. Eight of the samples were used as control;while other eight samples each were admixed with calcium nitrate and sodium nitrite in concrete cubes. It was later immersed in seawater and cassava fluid for a total duration of 32 days and the measurements were taken at the interval of 4 days in order to determine the corrosion rates in mils per year (mmpy). Two controls and admixed samples each were later immersed in seawater and cassava fluid, respectively, for durations of 32 days to determine the corrosion potentials using a voltmeter and a Copper-Copper Sulphate Electrode (Cu/CuSO4). The pH of each medium was measured throughout the period of exposure. The results obtained expressed that all the samples except the control samples, displayed some degree of inhibition. The inhibition levels for the admixed samples in seawater were higher compared with those in cassava fluid. Inhibition efficiencies for various inhibitors followed different trends in different environment. The inhibition efficiencies for calcium nitrate in cassava fluid and seawater were 26.81% and 64.85% respectively. The study concluded that inorganic inhibitors were effective in inhibiting corrosion in cyanide and chloride contaminated concrete cubes.
