Protection of internally displaced persons in Kenya under the Prevention, Protection and Assistance to Internally Displaced Persons and Affected Communities Act of 2012: an appraisal
- Authors: Juma, Laurence
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126122 , vital:35851 , https://hdl.handle.net/10520/EJC-107c9cba58
- Description: This article discusses Kenya’s Prevention, Protection and Assistance to Internally Displaced Persons and Affected Communities Act of 2012, which is among the very few national legislations globally that addresses the plight of internally displaced persons. While it records the momentous achievement in creating a viable and legally enforceable legislative framework for the protection of IDPs, the article highlights some of the areas that could be improved for the Act to realise its promise. It notes for example the inchoate manner in which institutions are created and the lack of resources. The article while isolating these challenges also suggests numerous ways in which such challenges can be overcome. It underscores the need for harmonised legal regimes, improvement of data collection and proper monitoring programmes, all which can be achieved and strengthened by a supportive political establishment as well as strategic amendments to various provisions of the Act.
- Full Text: false
- Date Issued: 2018
- Authors: Juma, Laurence
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126122 , vital:35851 , https://hdl.handle.net/10520/EJC-107c9cba58
- Description: This article discusses Kenya’s Prevention, Protection and Assistance to Internally Displaced Persons and Affected Communities Act of 2012, which is among the very few national legislations globally that addresses the plight of internally displaced persons. While it records the momentous achievement in creating a viable and legally enforceable legislative framework for the protection of IDPs, the article highlights some of the areas that could be improved for the Act to realise its promise. It notes for example the inchoate manner in which institutions are created and the lack of resources. The article while isolating these challenges also suggests numerous ways in which such challenges can be overcome. It underscores the need for harmonised legal regimes, improvement of data collection and proper monitoring programmes, all which can be achieved and strengthened by a supportive political establishment as well as strategic amendments to various provisions of the Act.
- Full Text: false
- Date Issued: 2018
Phototransferred thermoluminescence and thermally-assisted optically stimulated luminescence dosimetry using α-Al2O3:C,Mg annealed at 1200°C
- Kalita, Jitumani M, Chithambo, Makaiko L
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/105422 , vital:32511 , https://doi.org/10.1016/j.jlumin.2018.08.085
- Description: We report phototransferred thermoluminescence (PTTL) and thermally-assisted optically stimulated luminescence (TA-OSL) of α-Al2O3:C,Mg annealed at 1200 °C. PTTL is TL measured from an irradiated phosphor after its exposure to light. The other theme of this study, TA-OSL is the additional amount of luminescence optically stimulated from a sample over and above the amount that would be measured at room temperature. A sample irradiated to 10 Gy and preheated to 230 °C at 1 °C/s followed by illumination by 470 nm blue light produced four PTTL peaks at 53, 80, 102 and 173 °C. The PTTL peaks occur at the same positions as the corresponding conventional TL peaks. Their kinetic parameters are also similar. The intensity of the PTTL peaks increased with duration of illumination to a maximum within 200 s for doses between 1 Gy and 10 Gy. The dose response of each of the PTTL peaks at 80, 102 and 173 °C is linear within 1–15 Gy. The rate of fading is low and the peaks are reproducible. When the irradiated sample is optically stimulated at temperatures between 30 °C and 300 °C, after preheating to 500 °C, the intensity of its TA-OSL goes through a peak with temperature at 200 °C. Using the rising edge of the plot, activation energy of thermal assistance for a deep electron trap was estimated as (0.21 ± 0.02) eV. The TA-OSL dose response is sublinear from 10–250 Gy and saturates thereafter. The PTTL and TA-OSL analyses signify that the concentration of deep traps in α-Al2O3:C,Mg increased after annealing at 1200 °C. As a result, the sample produced better PTTL and TA-OSL response than when annealed at lower temperature.
- Full Text: false
- Date Issued: 2018
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/105422 , vital:32511 , https://doi.org/10.1016/j.jlumin.2018.08.085
- Description: We report phototransferred thermoluminescence (PTTL) and thermally-assisted optically stimulated luminescence (TA-OSL) of α-Al2O3:C,Mg annealed at 1200 °C. PTTL is TL measured from an irradiated phosphor after its exposure to light. The other theme of this study, TA-OSL is the additional amount of luminescence optically stimulated from a sample over and above the amount that would be measured at room temperature. A sample irradiated to 10 Gy and preheated to 230 °C at 1 °C/s followed by illumination by 470 nm blue light produced four PTTL peaks at 53, 80, 102 and 173 °C. The PTTL peaks occur at the same positions as the corresponding conventional TL peaks. Their kinetic parameters are also similar. The intensity of the PTTL peaks increased with duration of illumination to a maximum within 200 s for doses between 1 Gy and 10 Gy. The dose response of each of the PTTL peaks at 80, 102 and 173 °C is linear within 1–15 Gy. The rate of fading is low and the peaks are reproducible. When the irradiated sample is optically stimulated at temperatures between 30 °C and 300 °C, after preheating to 500 °C, the intensity of its TA-OSL goes through a peak with temperature at 200 °C. Using the rising edge of the plot, activation energy of thermal assistance for a deep electron trap was estimated as (0.21 ± 0.02) eV. The TA-OSL dose response is sublinear from 10–250 Gy and saturates thereafter. The PTTL and TA-OSL analyses signify that the concentration of deep traps in α-Al2O3:C,Mg increased after annealing at 1200 °C. As a result, the sample produced better PTTL and TA-OSL response than when annealed at lower temperature.
- Full Text: false
- Date Issued: 2018
The effect of annealing and beta irradiation on thermoluminescence spectra of α-Al2O3: C, Mg
- Kalita, Jitumani M, Chithambo, Makaiko L
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/112875 , vital:33669 , https://doi.org/10.1016/j.jlumin.2017.12.036
- Description: The effect of annealing on thermoluminescence spectra of beta irradiated α-Al2O3:C,Mg has been studied. Measurements were made on an un-annealed sample and samples annealed at 600, 700 and 900 °C. A glow curve measured at 1 °C/s from samples irradiated to 1 Gy shows a high intensity peak at 163 °C and six secondary peaks of weaker intensity at 43, 73, 195, 280, 329 and 370 °C. When the samples are annealed at 700 or 900 °C, an additional secondary peak appears at 100 °C. The thermoluminescence spectrum of an un-annealed sample measured at 1 °C/s between 300 and 700 nm shows the main emission band at ~ 410 nm and subsidiary emission bands at ~ 325 and 485 nm. The emission from samples annealed at 700 and 900 °C show similar bands except for a decrease in intensity of the emission at 485 nm. The emission bands at 325, 410 and 485 nm are attributed to F+, F and F22+(2Mg) -centres respectively. The decrease of the emission band at 485 nm is deduced to be due to the destruction of the F22+(2Mg) centre at 700 °C. The emission bands are unaffected by irradiation dose between 10 and 320 Gy. However, when the sample is annealed at or beyond 700 °C, any effects on the F+ and F centres emission can be easier distinguished particularly for doses greater than 10 Gy.
- Full Text: false
- Date Issued: 2018
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/112875 , vital:33669 , https://doi.org/10.1016/j.jlumin.2017.12.036
- Description: The effect of annealing on thermoluminescence spectra of beta irradiated α-Al2O3:C,Mg has been studied. Measurements were made on an un-annealed sample and samples annealed at 600, 700 and 900 °C. A glow curve measured at 1 °C/s from samples irradiated to 1 Gy shows a high intensity peak at 163 °C and six secondary peaks of weaker intensity at 43, 73, 195, 280, 329 and 370 °C. When the samples are annealed at 700 or 900 °C, an additional secondary peak appears at 100 °C. The thermoluminescence spectrum of an un-annealed sample measured at 1 °C/s between 300 and 700 nm shows the main emission band at ~ 410 nm and subsidiary emission bands at ~ 325 and 485 nm. The emission from samples annealed at 700 and 900 °C show similar bands except for a decrease in intensity of the emission at 485 nm. The emission bands at 325, 410 and 485 nm are attributed to F+, F and F22+(2Mg) -centres respectively. The decrease of the emission band at 485 nm is deduced to be due to the destruction of the F22+(2Mg) centre at 700 °C. The emission bands are unaffected by irradiation dose between 10 and 320 Gy. However, when the sample is annealed at or beyond 700 °C, any effects on the F+ and F centres emission can be easier distinguished particularly for doses greater than 10 Gy.
- Full Text: false
- Date Issued: 2018
Thermally and optically stimulated luminescence of natural red and blue corundum (Al2O3)
- Kalita, Jitumani M, Thomas, Sunil, Chithambo, Makaiko L
- Authors: Kalita, Jitumani M , Thomas, Sunil , Chithambo, Makaiko L
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/105177 , vital:32472 , https://doi.org/10.1016/j.jlumin.2018.09.058
- Description: We report the thermoluminescence (TL) and optically stimulated luminescence (OSL) of natural corundum (Al2O3) of two varieties; one red and the other blue. X-ray fluorescence spectroscopy of the samples show that the concentration of Al2O3 in the red corundum is 43.05% and 46.87% in the blue corundum. TL measurements carried out on un-annealed samples and samples annealed at 700 °C, 900 °C and 1200 °C show that the TL sensitivity increases with annealing. The sensitivity of the red corundum reaches a maximum after annealing at 900 °C whereas that of the blue corundum increases with annealing up to the maximum annealing temperature of 1200 °C used in this study. Both samples have a complex glow curve between 30 °C and 500 °C. The composite nature of the glow curves is deduced to be due to a continuum in the trap distribution in the crystal. The activation energy of the traps vary between 0.70 eV and 1.15 eV. The dose response of the red corundum under TL is linear within 100‒1000 Gy whereas that of the blue corundum is superlinear for the same dose range. The TL of both samples is reproducible but the signal fades with time between irradiation and measurement. Both samples produce OSL under 470 nm blue light stimulation. The dose response of the OSL is superlinear within 100‒1000 Gy. It is found that the samples also produce thermally-assisted OSL (TA-OSL) at elevated temperature. The TA-OSL intensity of the red corundum increases with dose up to 400 Gy and saturates thereafter. On the other hand, the intensity of the blue corundum increases consistently with dose from 100 Gy to 1000 Gy.
- Full Text: false
- Date Issued: 2019
- Authors: Kalita, Jitumani M , Thomas, Sunil , Chithambo, Makaiko L
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/105177 , vital:32472 , https://doi.org/10.1016/j.jlumin.2018.09.058
- Description: We report the thermoluminescence (TL) and optically stimulated luminescence (OSL) of natural corundum (Al2O3) of two varieties; one red and the other blue. X-ray fluorescence spectroscopy of the samples show that the concentration of Al2O3 in the red corundum is 43.05% and 46.87% in the blue corundum. TL measurements carried out on un-annealed samples and samples annealed at 700 °C, 900 °C and 1200 °C show that the TL sensitivity increases with annealing. The sensitivity of the red corundum reaches a maximum after annealing at 900 °C whereas that of the blue corundum increases with annealing up to the maximum annealing temperature of 1200 °C used in this study. Both samples have a complex glow curve between 30 °C and 500 °C. The composite nature of the glow curves is deduced to be due to a continuum in the trap distribution in the crystal. The activation energy of the traps vary between 0.70 eV and 1.15 eV. The dose response of the red corundum under TL is linear within 100‒1000 Gy whereas that of the blue corundum is superlinear for the same dose range. The TL of both samples is reproducible but the signal fades with time between irradiation and measurement. Both samples produce OSL under 470 nm blue light stimulation. The dose response of the OSL is superlinear within 100‒1000 Gy. It is found that the samples also produce thermally-assisted OSL (TA-OSL) at elevated temperature. The TA-OSL intensity of the red corundum increases with dose up to 400 Gy and saturates thereafter. On the other hand, the intensity of the blue corundum increases consistently with dose from 100 Gy to 1000 Gy.
- Full Text: false
- Date Issued: 2019
Comprehensive kinetic analysis of thermoluminescence peaks of α-Al2O3: C, Mg
- Kalita, Jitumani M, Chithambo, Makaiko L
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/116142 , vital:34323 , https://doi.org/10.1016/j.jlumin.2017.01.003
- Description: A comprehensive kinetic analysis of the glow peaks in α-Al2O3:C,Mg is reported. A thermoluminescence glow curve measured at 1 °C/s after beta irradiation to 1 Gy shows a high intensity peak hereafter referred to as the main peak at 161 °C and six lower intensity secondary peaks at 42, 72, 193, 279, 330, 370 °C respectively. For ease of reference, the secondary peaks are labelled as I, II, IV, V, VI and VII respectively and the main peak denoted peak III. Kinetic analysis of the glow peaks has been carried out using the initial rise, whole glow peak, peak shape, variable heating rate and glow curve deconvolution methods as well as by way of phosphorescence. Using Tm-Tstop, Tm-dose and phosphorescence analyses, the order of kinetics of the peaks has been evaluated as first order. Analysis by the peak shape, whole glow peak and deconvolution methods produce the same conclusion. The activation energy of peaks I through VII are calculated as ~0.83, 0.96, 1.37, 1.20, 1.15, 1.61 and 1.94 eV respectively. The frequency factors for all the peaks are of the order of 109 to 1014 s−1. The question of thermal quenching affecting the peaks was considered. The peaks III, IV and V, the only ones that could be conveniently studied in this regard, were found to be affected by thermal quenching. The activation energy for thermal quenching was calculated for peak III as 0.96±0.03 eV, for peak VI as 0.95±0.07 eV and for peak V as 1.26±0.08 eV. The thermal quenching phenomenon has been discussed with reference to F+ and F centres. An energy band model has been developed to discuss the luminescence mechanisms in α-Al2O3:C,Mg in light of finding in this work.
- Full Text: false
- Date Issued: 2017
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/116142 , vital:34323 , https://doi.org/10.1016/j.jlumin.2017.01.003
- Description: A comprehensive kinetic analysis of the glow peaks in α-Al2O3:C,Mg is reported. A thermoluminescence glow curve measured at 1 °C/s after beta irradiation to 1 Gy shows a high intensity peak hereafter referred to as the main peak at 161 °C and six lower intensity secondary peaks at 42, 72, 193, 279, 330, 370 °C respectively. For ease of reference, the secondary peaks are labelled as I, II, IV, V, VI and VII respectively and the main peak denoted peak III. Kinetic analysis of the glow peaks has been carried out using the initial rise, whole glow peak, peak shape, variable heating rate and glow curve deconvolution methods as well as by way of phosphorescence. Using Tm-Tstop, Tm-dose and phosphorescence analyses, the order of kinetics of the peaks has been evaluated as first order. Analysis by the peak shape, whole glow peak and deconvolution methods produce the same conclusion. The activation energy of peaks I through VII are calculated as ~0.83, 0.96, 1.37, 1.20, 1.15, 1.61 and 1.94 eV respectively. The frequency factors for all the peaks are of the order of 109 to 1014 s−1. The question of thermal quenching affecting the peaks was considered. The peaks III, IV and V, the only ones that could be conveniently studied in this regard, were found to be affected by thermal quenching. The activation energy for thermal quenching was calculated for peak III as 0.96±0.03 eV, for peak VI as 0.95±0.07 eV and for peak V as 1.26±0.08 eV. The thermal quenching phenomenon has been discussed with reference to F+ and F centres. An energy band model has been developed to discuss the luminescence mechanisms in α-Al2O3:C,Mg in light of finding in this work.
- Full Text: false
- Date Issued: 2017
Thermoluminescence of α-Al2O3: C, Mg annealed at 1200° C
- Kalita, Jitumani M, Chithambo, Makaiko L
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/111030 , vital:33365 , https://doi.org/10.1016/j.nimb.2018.03.003
- Description: Stimulated luminescence in α-Al2O3:C,Mg has thus far been studied for samples annealed at temperature no higher than 900 °C as can be seen by an examination of the literature. We report the thermoluminescence (TL) features of α-Al2O3:C,Mg annealed at 1200 °C. A glow curve measured at 1 °C/s from the samples annealed at 1200 °C shows eight peaks at 54, 80, 102, 173, 238, 290, 330 and 387 °C. Kinetic analyses show that the peak at 54 °C follows general order kinetics (b = 1.3) whereas the rest follow first order kinetics. The values of the activation energy of the peaks are between 0.77 eV and 1.90 eV and the frequency factors are of the order of 1010–1014 s−1. The intensity of the peaks at 54, 80, 102 and 173 °C increase with heating rate whereas those of the peaks at 238 and 290 °C decrease with heating rate. The decrease of intensity of the peaks at 238 and 290 °C with heating rate is due to thermal quenching whereas the increase of intensity of the peaks with heating rate indicates an inverse thermal-quenching-like behaviour. Interestingly this behaviour is observed only after annealing at 1200 °C. The activation energy for thermal quenching as calculated using the peaks at 238 and 290 °C are (1.02 ± 0.16) eV and (1.33 ± 0.15) eV respectively. Regarding the dosimetric features, the dose response of the peaks at 54, 80 and 102 °C are sublinear within 1–10 Gy and the peak at 54 °C saturates above 6 Gy. In contrast, the response of the peak at 173 °C is sublinear with 1–4 Gy and superlinear between 4 and 10 Gy. The peaks are found to fade at different rates and the rate of fading is also affected by annealing.
- Full Text: false
- Date Issued: 2018
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/111030 , vital:33365 , https://doi.org/10.1016/j.nimb.2018.03.003
- Description: Stimulated luminescence in α-Al2O3:C,Mg has thus far been studied for samples annealed at temperature no higher than 900 °C as can be seen by an examination of the literature. We report the thermoluminescence (TL) features of α-Al2O3:C,Mg annealed at 1200 °C. A glow curve measured at 1 °C/s from the samples annealed at 1200 °C shows eight peaks at 54, 80, 102, 173, 238, 290, 330 and 387 °C. Kinetic analyses show that the peak at 54 °C follows general order kinetics (b = 1.3) whereas the rest follow first order kinetics. The values of the activation energy of the peaks are between 0.77 eV and 1.90 eV and the frequency factors are of the order of 1010–1014 s−1. The intensity of the peaks at 54, 80, 102 and 173 °C increase with heating rate whereas those of the peaks at 238 and 290 °C decrease with heating rate. The decrease of intensity of the peaks at 238 and 290 °C with heating rate is due to thermal quenching whereas the increase of intensity of the peaks with heating rate indicates an inverse thermal-quenching-like behaviour. Interestingly this behaviour is observed only after annealing at 1200 °C. The activation energy for thermal quenching as calculated using the peaks at 238 and 290 °C are (1.02 ± 0.16) eV and (1.33 ± 0.15) eV respectively. Regarding the dosimetric features, the dose response of the peaks at 54, 80 and 102 °C are sublinear within 1–10 Gy and the peak at 54 °C saturates above 6 Gy. In contrast, the response of the peak at 173 °C is sublinear with 1–4 Gy and superlinear between 4 and 10 Gy. The peaks are found to fade at different rates and the rate of fading is also affected by annealing.
- Full Text: false
- Date Issued: 2018
On the sensitivity of thermally and optically stimulated luminescence of α-Al2O3: C and α-Al2O3: C, Mg
- Kalita, Jitumani M, Chithambo, Makaiko L
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/119803 , vital:34784 , https://doi.org/10.1016/j.radmeas.2017.03.006
- Description: The luminescence sensitivity of α-Al2O3:C and α-Al2O3:C, Mg is of interest because of the contemporary use of these materials in dosimetry related applications. We report investigations concerning the change in sensitivity of thermoluminescence (TL) and optically stimulated luminescence (OSL) from α-Al2O3:C and α-Al2O3:C, Mg with re-use. The study was carried out on a set of un-annealed samples and others annealed at 700 and 900 °C. The TL and OSL sensitivity in α-Al2O3:C and α-Al2O3:C, Mg was found to increase with sample re-use whether the intensity was monitored as peak area or peak height for the main TL peak or, in the case of OSL, as the maximum intensity or the area under a decay curve. The fractional increase in area under either the main TL peak or the OSL decay curve exceeds that of the TL peak height or maximum OSL intensity when samples are re-used. However, when un-annealed samples are used, any increase in TL peak height or peak area per measurement is less than observed in annealed samples. It is also interesting to note that the change in maximum OSL intensity or OSL area is minimal for samples annealed at 900 °C. In general, the TL sensitivity in α-Al2O3:C increases more than that in α-Al2O3:C, Mg with re-use. On the other hand, the OSL sensitivity in α-Al2O3:C, Mg increases more than that in α-Al2O3:C with re-use. These findings suggest that it is advisable to take into account the fractional increase in sensitivity per measurement when one uses α-Al2O3:C as a TL dosimeter and α-Al2O3:C, Mg as an OSL dosimeter.
- Full Text: false
- Date Issued: 2017
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/119803 , vital:34784 , https://doi.org/10.1016/j.radmeas.2017.03.006
- Description: The luminescence sensitivity of α-Al2O3:C and α-Al2O3:C, Mg is of interest because of the contemporary use of these materials in dosimetry related applications. We report investigations concerning the change in sensitivity of thermoluminescence (TL) and optically stimulated luminescence (OSL) from α-Al2O3:C and α-Al2O3:C, Mg with re-use. The study was carried out on a set of un-annealed samples and others annealed at 700 and 900 °C. The TL and OSL sensitivity in α-Al2O3:C and α-Al2O3:C, Mg was found to increase with sample re-use whether the intensity was monitored as peak area or peak height for the main TL peak or, in the case of OSL, as the maximum intensity or the area under a decay curve. The fractional increase in area under either the main TL peak or the OSL decay curve exceeds that of the TL peak height or maximum OSL intensity when samples are re-used. However, when un-annealed samples are used, any increase in TL peak height or peak area per measurement is less than observed in annealed samples. It is also interesting to note that the change in maximum OSL intensity or OSL area is minimal for samples annealed at 900 °C. In general, the TL sensitivity in α-Al2O3:C increases more than that in α-Al2O3:C, Mg with re-use. On the other hand, the OSL sensitivity in α-Al2O3:C, Mg increases more than that in α-Al2O3:C with re-use. These findings suggest that it is advisable to take into account the fractional increase in sensitivity per measurement when one uses α-Al2O3:C as a TL dosimeter and α-Al2O3:C, Mg as an OSL dosimeter.
- Full Text: false
- Date Issued: 2017
Features of an annealing-induced thermoluminescence peak in α-Al2O3: C, Mg
- Kalita, Jitumani M, Chithambo, Makaiko L
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/116013 , vital:34289 , DOI: 10.1016/j.optmat.2017.05.034
- Description: We report the thermoluminescence glow curves of beta irradiated single crystal α-Al2O3:C,Mg after annealing at 700 and 900 °C. A glow curve measured at 1 °C/s from samples irradiated to 1 Gy following annealing at 700 and 900 °C shows a high intensity peak at 163 °C and seven secondary peaks of weaker intensity at 43, 73, 100, 195, 280, 329 and 370 °C. Comparing the position of the peaks in the annealed samples with those in an un-annealed one, it is observed that the peak at 100 °C appears only after annealing at and above 700 °C. Kinetic analysis of this annealing-induced peak was carried out using the initial rise, whole glow peak, peak shape, curve fitting and variable heating rate methods. The order of kinetics of the peak was determined as first order using various methods including the Tm-Tstop technique and the dependence of Tm on irradiation dose. The activation energy of the peak is about 1.01 eV and the frequency factor of the order of 1012 s−1. The peak was found to be affected by thermal quenching in analysis based on change of peak intensity with heating rate. The activation energy of thermal quenching was evaluated as 1.06 ± 0.08 eV. We speculate that the annealing-induced peak is due to formation of a new electron trap after destruction of the F22+(2 Mg) centre when the sample is annealed at 700 °C. The annealing-induced peak fades with storage between irradiation and measurement. It was also concluded that electrons from traps corresponding to secondary peaks get re-trapped at the main electron trap.
- Full Text: false
- Date Issued: 2017
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/116013 , vital:34289 , DOI: 10.1016/j.optmat.2017.05.034
- Description: We report the thermoluminescence glow curves of beta irradiated single crystal α-Al2O3:C,Mg after annealing at 700 and 900 °C. A glow curve measured at 1 °C/s from samples irradiated to 1 Gy following annealing at 700 and 900 °C shows a high intensity peak at 163 °C and seven secondary peaks of weaker intensity at 43, 73, 100, 195, 280, 329 and 370 °C. Comparing the position of the peaks in the annealed samples with those in an un-annealed one, it is observed that the peak at 100 °C appears only after annealing at and above 700 °C. Kinetic analysis of this annealing-induced peak was carried out using the initial rise, whole glow peak, peak shape, curve fitting and variable heating rate methods. The order of kinetics of the peak was determined as first order using various methods including the Tm-Tstop technique and the dependence of Tm on irradiation dose. The activation energy of the peak is about 1.01 eV and the frequency factor of the order of 1012 s−1. The peak was found to be affected by thermal quenching in analysis based on change of peak intensity with heating rate. The activation energy of thermal quenching was evaluated as 1.06 ± 0.08 eV. We speculate that the annealing-induced peak is due to formation of a new electron trap after destruction of the F22+(2 Mg) centre when the sample is annealed at 700 °C. The annealing-induced peak fades with storage between irradiation and measurement. It was also concluded that electrons from traps corresponding to secondary peaks get re-trapped at the main electron trap.
- Full Text: false
- Date Issued: 2017
Temperature dependence of optically stimulated luminescence of α-Al2O3: C, Mg
- Kalita, Jitumani M, Chithambo, Makaiko L
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/115708 , vital:34217 , https://doi.org/10.1016/j.radmeas.2017.08.009
- Description: Thermal assistance and thermal quenching are two independently acting thermodynamic phenomena that simultaneously affect the stimulation of luminescence. We have studied thermal assistance to luminescence optically stimulated from α-Al2O3:C,Mg. Since thermal assistance causes only a minor change in the luminescence intensity, measurements were made after the sample had been pre-exposed to stimulating light to reduce its intensity significantly, that is, in the slow component of its decay curve. The luminescence intensity was monitored as a function of measurement temperature between 30 and 130 °C. The intensity goes through a peak at 60 °C due to competing effects of thermal assistance and thermal quenching. The initial increase of intensity is attributed to dominant thermal assistance whereas the subsequent decrease of intensity is ascribed to dominant thermal quenching. The activation energy for thermal assistance was calculated for the main electron trap of an un-annealed sample as 0.324 ± 0.020 eV and in a sample annealed at 900 °C as 0.416 ± 0.028 eV. Implications of such differences in the value of the activation energy for thermal assistance are considered.
- Full Text: false
- Date Issued: 2017
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/115708 , vital:34217 , https://doi.org/10.1016/j.radmeas.2017.08.009
- Description: Thermal assistance and thermal quenching are two independently acting thermodynamic phenomena that simultaneously affect the stimulation of luminescence. We have studied thermal assistance to luminescence optically stimulated from α-Al2O3:C,Mg. Since thermal assistance causes only a minor change in the luminescence intensity, measurements were made after the sample had been pre-exposed to stimulating light to reduce its intensity significantly, that is, in the slow component of its decay curve. The luminescence intensity was monitored as a function of measurement temperature between 30 and 130 °C. The intensity goes through a peak at 60 °C due to competing effects of thermal assistance and thermal quenching. The initial increase of intensity is attributed to dominant thermal assistance whereas the subsequent decrease of intensity is ascribed to dominant thermal quenching. The activation energy for thermal assistance was calculated for the main electron trap of an un-annealed sample as 0.324 ± 0.020 eV and in a sample annealed at 900 °C as 0.416 ± 0.028 eV. Implications of such differences in the value of the activation energy for thermal assistance are considered.
- Full Text: false
- Date Issued: 2017
Temperature dependence of persistent luminescence in CaAl2O4: Eu2+, Nd3+ related to beta irradiation and optical excitation
- Kalita, Jitumani M, Chithambo, Makaiko L
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/105158 , vital:32470 , https://doi.org/10.1016/j.jlumin.2018.10.062
- Description: Mechanisms responsible for the emission of persistent luminescence in CaAl2O4:Eu2+,Nd3+ are typically studied following excitation by ultraviolet or visible light. In contrast, we have studied the persistent luminescence from this material after beta irradiation and optical excitation. These studies have been carried out at 25 °C as well as at various temperatures up to 100 °C. A thermoluminescence (TL) glow curve measured at 1 °C/s following beta irradiation showed a glow peak at 63 °C. On the other hand, a glow curve measured after 15 s of optical excitation by polychromatic white light shows a peak at 102 °C. The partial heating procedure reveals that each of the TL peaks consist of several overlapping components. The TL in each case was analysed for kinetic parameters. The initial rise analysis carried out on the rising edge of the overlapping components shows that the activation energy of the component peaks corresponding to beta irradiation is consistent at (0.59 ± 0.01) eV. In comparison, activation energies corresponding to optical excitation increases with the partial heating temperature from (0.71 ± 0.01) eV to (0.76 ± 0.01) eV. The activation energy of (0.59 ± 0.01) eV is ascribed to an oxygen vacancy whereas the range of activation energies between (0.71 ± 0.01) eV and (0.76 ± 0.01) eV is ascribed to the 4 f levels of the Nd dopant.
- Full Text: false
- Date Issued: 2019
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/105158 , vital:32470 , https://doi.org/10.1016/j.jlumin.2018.10.062
- Description: Mechanisms responsible for the emission of persistent luminescence in CaAl2O4:Eu2+,Nd3+ are typically studied following excitation by ultraviolet or visible light. In contrast, we have studied the persistent luminescence from this material after beta irradiation and optical excitation. These studies have been carried out at 25 °C as well as at various temperatures up to 100 °C. A thermoluminescence (TL) glow curve measured at 1 °C/s following beta irradiation showed a glow peak at 63 °C. On the other hand, a glow curve measured after 15 s of optical excitation by polychromatic white light shows a peak at 102 °C. The partial heating procedure reveals that each of the TL peaks consist of several overlapping components. The TL in each case was analysed for kinetic parameters. The initial rise analysis carried out on the rising edge of the overlapping components shows that the activation energy of the component peaks corresponding to beta irradiation is consistent at (0.59 ± 0.01) eV. In comparison, activation energies corresponding to optical excitation increases with the partial heating temperature from (0.71 ± 0.01) eV to (0.76 ± 0.01) eV. The activation energy of (0.59 ± 0.01) eV is ascribed to an oxygen vacancy whereas the range of activation energies between (0.71 ± 0.01) eV and (0.76 ± 0.01) eV is ascribed to the 4 f levels of the Nd dopant.
- Full Text: false
- Date Issued: 2019
Phototransferred thermoluminescence in α-Al2O3: C, Mg under 470 nm blue light stimulation
- Kalita, Jitumani M, Chithambo, Makaiko L
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/116026 , vital:34290 , https://doi.org/10.1016/j.jlumin.2017.04.059
- Description: Phototransferred thermoluminescence (PTTL) in α-Al2O3:C,Mg under 470 nm blue light has been investigated. Conventional thermoluminescence (TL) measured at 1 °C/s following irradiation to 10 Gy shows the main peak (labelled as III) at 163 °C and six secondary peaks I, II, IV, V, VI and VII at 45, 74, 200, 279, 328, 370 °C respectively. When a sample irradiated to 10 Gy is preheated to 220 °C at 1 °C/s to remove peaks I, II, III and IV and then exposed to 470 nm blue light for 100 s, it is found that three peaks I, II and III are reproduced under phototransfer. Kinetic analysis of the PTTL peaks shows that their kinetic parameters are similar to those of peaks I, II and III from conventional TL. Pulse annealing experiments, intended to study the dependence of PTTL peak intensity on preheating temperature, show that the electron traps corresponding to peaks V, VI and VII act as donor traps whereas the traps corresponding to peaks I, II and III act as acceptor traps. Further, it was found that no PTTL can be generated when all the traps corresponding to peaks I, II…VII are erased by preheating after irradiation. The primary conclusion here is that α-Al2O3:C,Mg does not have any deep traps beyond 400 °C sensitive to 470 nm stimulation or if there are any, their concentration is negligible. The PTTL for any of the PTTL peaks mentioned earlier increases with illumination time to a maximum within 400 s for measurements corresponding to doses between 6 and 15 Gy. The dose response of PTTL peaks II and III is linear within 1–15 Gy. Regarding fading, PTTL peak II fades to background level within 18000 s whereas in the same time, PTTL peak III fades down to 40% of its initial intensity.
- Full Text: false
- Date Issued: 2017
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/116026 , vital:34290 , https://doi.org/10.1016/j.jlumin.2017.04.059
- Description: Phototransferred thermoluminescence (PTTL) in α-Al2O3:C,Mg under 470 nm blue light has been investigated. Conventional thermoluminescence (TL) measured at 1 °C/s following irradiation to 10 Gy shows the main peak (labelled as III) at 163 °C and six secondary peaks I, II, IV, V, VI and VII at 45, 74, 200, 279, 328, 370 °C respectively. When a sample irradiated to 10 Gy is preheated to 220 °C at 1 °C/s to remove peaks I, II, III and IV and then exposed to 470 nm blue light for 100 s, it is found that three peaks I, II and III are reproduced under phototransfer. Kinetic analysis of the PTTL peaks shows that their kinetic parameters are similar to those of peaks I, II and III from conventional TL. Pulse annealing experiments, intended to study the dependence of PTTL peak intensity on preheating temperature, show that the electron traps corresponding to peaks V, VI and VII act as donor traps whereas the traps corresponding to peaks I, II and III act as acceptor traps. Further, it was found that no PTTL can be generated when all the traps corresponding to peaks I, II…VII are erased by preheating after irradiation. The primary conclusion here is that α-Al2O3:C,Mg does not have any deep traps beyond 400 °C sensitive to 470 nm stimulation or if there are any, their concentration is negligible. The PTTL for any of the PTTL peaks mentioned earlier increases with illumination time to a maximum within 400 s for measurements corresponding to doses between 6 and 15 Gy. The dose response of PTTL peaks II and III is linear within 1–15 Gy. Regarding fading, PTTL peak II fades to background level within 18000 s whereas in the same time, PTTL peak III fades down to 40% of its initial intensity.
- Full Text: false
- Date Issued: 2017
The influence of dose on the kinetic parameters and dosimetric features of the main thermoluminescence glow peak in α-Al2O3: C, Mg
- Kalita, Jitumani M, Chithambo, Makaiko L
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/119834 , vital:34787 , https://doi.org/10.1016/j.nimb.2016.12.027
- Description: The influence of dose (0.1–100 Gy) on the kinetic parameters and the dosimetric features of the main glow peak of α-Al2O3:C,Mg have been investigated. Thermoluminescence (TL) measured at 1 °C/s shows a very high intensity glow peak at 161 °C and six secondary peaks at 42, 72, 193, 279, 330, 370 °C respectively. Analysis shows that the main peak follows first order kinetics irrespective of the irradiation dose. The activation energy is found to be consistent at 1.37 eV and the frequency factor is of the order of 1014 s−1 for any dose between 0.1 and 100 Gy. Further, the analysis for thermal quenching of the main peak of 0.1 Gy irradiated sample shows that the activation energy for thermal quenching is (0.94 ± 0.04) eV.
- Full Text: false
- Date Issued: 2017
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/119834 , vital:34787 , https://doi.org/10.1016/j.nimb.2016.12.027
- Description: The influence of dose (0.1–100 Gy) on the kinetic parameters and the dosimetric features of the main glow peak of α-Al2O3:C,Mg have been investigated. Thermoluminescence (TL) measured at 1 °C/s shows a very high intensity glow peak at 161 °C and six secondary peaks at 42, 72, 193, 279, 330, 370 °C respectively. Analysis shows that the main peak follows first order kinetics irrespective of the irradiation dose. The activation energy is found to be consistent at 1.37 eV and the frequency factor is of the order of 1014 s−1 for any dose between 0.1 and 100 Gy. Further, the analysis for thermal quenching of the main peak of 0.1 Gy irradiated sample shows that the activation energy for thermal quenching is (0.94 ± 0.04) eV.
- Full Text: false
- Date Issued: 2017
The effect of pre-dose on thermally and optically stimulated luminescence from α-Al2O3C, Mg and α-Al2O3: C
- Kalita, Jitumani M, Chithambo, Makaiko L
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/111011 , vital:33363 , https://doi.org/10.1016/j.apradiso.2018.06.012
- Description: We report the effect of pre-dose on the thermoluminescence (TL) and optically stimulated luminescence (OSL) dose response of α-Al2O3:C,Mg and α-Al2O3:C. Before any luminescence measurement, the samples were irradiated with different doses, namely 100, 500 and 1000 Gy to populate the deep electron traps. This is the pre-dose. The results from TL and OSL studies are compared with results from samples used without any pre-measurement dose. The TL glow curves and OSL decay curves of α-Al2O3:C,Mg recorded after pre-doses of 100, 500 and 1000 Gy are identical to those from a sample used without any pre-dose. Further, the TL and OSL dose response of all α-Al2O3:C,Mg samples are similar regardless of pre-dose. In comparison, the TL glow curves and OSL decay curves of α-Al2O3:C are influenced by pre-dose. We conclude that the differences in the TL and OSL dose response of various pre-dosed samples of α-Al2O3:C are due to the concentration of charge in the deep traps. On the other hand, owing to the lower concentration of such deep traps in α-Al2O3:C,Mg, the TL or OSL dose responses are not affected by pre-dose in this material.
- Full Text: false
- Date Issued: 2018
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/111011 , vital:33363 , https://doi.org/10.1016/j.apradiso.2018.06.012
- Description: We report the effect of pre-dose on the thermoluminescence (TL) and optically stimulated luminescence (OSL) dose response of α-Al2O3:C,Mg and α-Al2O3:C. Before any luminescence measurement, the samples were irradiated with different doses, namely 100, 500 and 1000 Gy to populate the deep electron traps. This is the pre-dose. The results from TL and OSL studies are compared with results from samples used without any pre-measurement dose. The TL glow curves and OSL decay curves of α-Al2O3:C,Mg recorded after pre-doses of 100, 500 and 1000 Gy are identical to those from a sample used without any pre-dose. Further, the TL and OSL dose response of all α-Al2O3:C,Mg samples are similar regardless of pre-dose. In comparison, the TL glow curves and OSL decay curves of α-Al2O3:C are influenced by pre-dose. We conclude that the differences in the TL and OSL dose response of various pre-dosed samples of α-Al2O3:C are due to the concentration of charge in the deep traps. On the other hand, owing to the lower concentration of such deep traps in α-Al2O3:C,Mg, the TL or OSL dose responses are not affected by pre-dose in this material.
- Full Text: false
- Date Issued: 2018
Thermally-assisted optically stimulated luminescence from deep electron traps in α-Al2O3: C, Mg
- Kalita, Jitumani M, Chithambo, Makaiko L, Polymeris, G S
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L , Polymeris, G S
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/116133 , vital:34322 , https://doi.org/10.1016/j.nimb.2017.04.075
- Description: We report thermally-assisted optically stimulated luminescence (TA-OSL) in α-Al2O3:C,Mg. The OSL was measured at elevated temperatures between 50 and 240 °C from a sample preheated to 500 °C after irradiation to 100 Gy. That OSL could be measured even after the preheating is direct evidence of the existence of deep electron traps in α-Al2O3:C,Mg. The TA-OSL intensity goes through a peak with measurement temperature. The initial increase is ascribed to thermal assistance to optical stimulation whereas the subsequent decrease in intensity is deduced to reflect increasing incidences of non-radiative recombination, that is, thermal quenching. The activation energy for thermal assistance corresponding to a deep electron trap was estimated as 0.667 ± 0.006 eV whereas the activation energy for thermal quenching was calculated as 0.90 ± 0.04 eV. The intensity of the TA-OSL was also found to increase with irradiation dose. The dose response is sublinear from 25 to 150 Gy but saturates with further increase of dose. The TA-OSL dose response has been discussed by considering the competition for charges at the deep traps. This study incidentally shows that TA-OSL can be effectively used in dosimetry involving large doses.
- Full Text: false
- Date Issued: 2017
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L , Polymeris, G S
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/116133 , vital:34322 , https://doi.org/10.1016/j.nimb.2017.04.075
- Description: We report thermally-assisted optically stimulated luminescence (TA-OSL) in α-Al2O3:C,Mg. The OSL was measured at elevated temperatures between 50 and 240 °C from a sample preheated to 500 °C after irradiation to 100 Gy. That OSL could be measured even after the preheating is direct evidence of the existence of deep electron traps in α-Al2O3:C,Mg. The TA-OSL intensity goes through a peak with measurement temperature. The initial increase is ascribed to thermal assistance to optical stimulation whereas the subsequent decrease in intensity is deduced to reflect increasing incidences of non-radiative recombination, that is, thermal quenching. The activation energy for thermal assistance corresponding to a deep electron trap was estimated as 0.667 ± 0.006 eV whereas the activation energy for thermal quenching was calculated as 0.90 ± 0.04 eV. The intensity of the TA-OSL was also found to increase with irradiation dose. The dose response is sublinear from 25 to 150 Gy but saturates with further increase of dose. The TA-OSL dose response has been discussed by considering the competition for charges at the deep traps. This study incidentally shows that TA-OSL can be effectively used in dosimetry involving large doses.
- Full Text: false
- Date Issued: 2017
Thermoluminescence of α-Al2O3: C, Mg: kinetic analysis of the main glow peak
- Kalita, Jitumani M, Chithambo, Makaiko L
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/119844 , vital:34788 , https://doi.org/10.1016/j.jlumin.2016.10.031
- Description: The kinetic analysis of the thermoluminescence of aluminium oxide doped with carbon and co-doped with magnesium (α-Al2O3:C,Mg) is reported. Measurements were made at 1 °C/s following beta irradiation to 1 Gy. The glow curve consists of a dominant peak at a peak-maximum Tm of 161 °C and six secondary peaks of weaker intensity at 42, 72, 193, 279, 330 and 370 °C. Kinetic analysis of the main peak, the subject of this report, was carried out using initial rise, whole glow peak, peak shape, curve fitting and variable heating rate methods. The order of kinetics of the main peak was determined as first order using various methods including the Tm–Tstop technique and the dependence of Tm on irradiation dose. The activation energy of the peak is about ~1.36 eV and the frequency factor of the order of 1014 s−1. The peak area changes with heating rate in a manner that shows that the peak is affected by thermal quenching. The activation energy of thermal quenching was evaluated as 0.99±0.08 eV. A comparison of analytical results from the main peak before and after correction for thermal quenching show that the kinetic parameters of the main peak are not that affected by thermal quenching.
- Full Text: false
- Date Issued: 2017
- Authors: Kalita, Jitumani M , Chithambo, Makaiko L
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/119844 , vital:34788 , https://doi.org/10.1016/j.jlumin.2016.10.031
- Description: The kinetic analysis of the thermoluminescence of aluminium oxide doped with carbon and co-doped with magnesium (α-Al2O3:C,Mg) is reported. Measurements were made at 1 °C/s following beta irradiation to 1 Gy. The glow curve consists of a dominant peak at a peak-maximum Tm of 161 °C and six secondary peaks of weaker intensity at 42, 72, 193, 279, 330 and 370 °C. Kinetic analysis of the main peak, the subject of this report, was carried out using initial rise, whole glow peak, peak shape, curve fitting and variable heating rate methods. The order of kinetics of the main peak was determined as first order using various methods including the Tm–Tstop technique and the dependence of Tm on irradiation dose. The activation energy of the peak is about ~1.36 eV and the frequency factor of the order of 1014 s−1. The peak area changes with heating rate in a manner that shows that the peak is affected by thermal quenching. The activation energy of thermal quenching was evaluated as 0.99±0.08 eV. A comparison of analytical results from the main peak before and after correction for thermal quenching show that the kinetic parameters of the main peak are not that affected by thermal quenching.
- Full Text: false
- Date Issued: 2017
Reinventing the oral word and returning it to the community via technauriture
- Kaschula, Russell H, Dlutu, Bongiwe
- Authors: Kaschula, Russell H , Dlutu, Bongiwe
- Date: 2015
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/67052 , vital:29024 , https://books.google.co.za/books?id=6IpwCgAAQBAJ
- Description: publisher version , From Introduction: The aim of this article is to situate the importance of orality in rural communities within the paradigm of Technauriture, which is defined below. The chapter will also explore/describe the process of orality supported through community meetings, oral histories, and story-telling, and how it interacts with the recording process facilitated through modern technology, as well as the return of the oral material via technology. These objectives will be pursued as part of empirical data collected at Tshani, an area falling within the in Mankosi tribal authority in the Eastern Cape Province of South Africa. Mankosi’s twelve villages are inhabited by amaXhosa people and is situated in the Ngqeleni district in the former Transkei region. Mankosi is about 76 kilometres away from Mthatha, the major city in that area. These villages are under the Nyandeni Local Municipality and are regarded as very disadvantaged. There is poor sanitation, gravel roads, and few local people have access to electricity. Most of the villagers depend on government support grants. These include Child Support Grants, Old Age Grants, Disability Grants, and Foster-Care Grants. Furthermore, most of the community is involved in small-scale agriculture for survival. People often move, temporarily, from their village to towns in order to gain employment, including domestic work and working on the mines in the mineral rich Gauteng Province. They send cash remittances home to their families. The primary technological devices that people in the village are familiar with would be radio and the cell phone. Even television sets are relatively uncommon.
- Full Text: false
- Date Issued: 2015
- Authors: Kaschula, Russell H , Dlutu, Bongiwe
- Date: 2015
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/67052 , vital:29024 , https://books.google.co.za/books?id=6IpwCgAAQBAJ
- Description: publisher version , From Introduction: The aim of this article is to situate the importance of orality in rural communities within the paradigm of Technauriture, which is defined below. The chapter will also explore/describe the process of orality supported through community meetings, oral histories, and story-telling, and how it interacts with the recording process facilitated through modern technology, as well as the return of the oral material via technology. These objectives will be pursued as part of empirical data collected at Tshani, an area falling within the in Mankosi tribal authority in the Eastern Cape Province of South Africa. Mankosi’s twelve villages are inhabited by amaXhosa people and is situated in the Ngqeleni district in the former Transkei region. Mankosi is about 76 kilometres away from Mthatha, the major city in that area. These villages are under the Nyandeni Local Municipality and are regarded as very disadvantaged. There is poor sanitation, gravel roads, and few local people have access to electricity. Most of the villagers depend on government support grants. These include Child Support Grants, Old Age Grants, Disability Grants, and Foster-Care Grants. Furthermore, most of the community is involved in small-scale agriculture for survival. People often move, temporarily, from their village to towns in order to gain employment, including domestic work and working on the mines in the mineral rich Gauteng Province. They send cash remittances home to their families. The primary technological devices that people in the village are familiar with would be radio and the cell phone. Even television sets are relatively uncommon.
- Full Text: false
- Date Issued: 2015
The amaXhosa ukuthwala marriage custom in fact and fiction: a contemporary critique
- Kaschula, Russell H, Huisamen, Tim, Mostert, Andre, Nosilela, Bulelwa
- Authors: Kaschula, Russell H , Huisamen, Tim , Mostert, Andre , Nosilela, Bulelwa
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68344 , vital:29241 , https://doi.org/10.1080/02572117.2013.871454
- Description: publisher version , Ukuthwala is traditionally a marriage custom within the amaXhosa culture in South Africa which permits a ‘legal abduction’ of a bride-to-be. Similar customs of ‘bridal abduction’ exist, most notably in Kyrgyzstan, where it is known as ala kachuu. Research into these customs necessitates a more innovative approach to explore the impact of this social phenomenon. In this article the authors mobilise a fictional narrative to offer a backdrop for a comparative assessment of the impact of bridal ‘legal abduction’ and assess its contemporary status and role within a multicultural society which celebrates the rights of the individual while recognising the value and importance of maintaining cultural identity and traditions. Cultural dissonance has always been characteristic of modern and post-modern societies as they strive for a workable shared ethos. However, when customs such as ‘legal abduction’ (Mtuze, 1993:50) continue under the veil of cultural rights, the wider social sensibilities and perspectives can be at odds with the maintenance of such activities where these activities contradict the rights of the individual as enshrined for example in what can be seen as a liberal South African Constitution.
- Full Text: false
- Date Issued: 2013
- Authors: Kaschula, Russell H , Huisamen, Tim , Mostert, Andre , Nosilela, Bulelwa
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68344 , vital:29241 , https://doi.org/10.1080/02572117.2013.871454
- Description: publisher version , Ukuthwala is traditionally a marriage custom within the amaXhosa culture in South Africa which permits a ‘legal abduction’ of a bride-to-be. Similar customs of ‘bridal abduction’ exist, most notably in Kyrgyzstan, where it is known as ala kachuu. Research into these customs necessitates a more innovative approach to explore the impact of this social phenomenon. In this article the authors mobilise a fictional narrative to offer a backdrop for a comparative assessment of the impact of bridal ‘legal abduction’ and assess its contemporary status and role within a multicultural society which celebrates the rights of the individual while recognising the value and importance of maintaining cultural identity and traditions. Cultural dissonance has always been characteristic of modern and post-modern societies as they strive for a workable shared ethos. However, when customs such as ‘legal abduction’ (Mtuze, 1993:50) continue under the veil of cultural rights, the wider social sensibilities and perspectives can be at odds with the maintenance of such activities where these activities contradict the rights of the individual as enshrined for example in what can be seen as a liberal South African Constitution.
- Full Text: false
- Date Issued: 2013
Technauriture as a platform to create an inclusive environment for the sharing of research
- Authors: Kaschula, Russell H
- Date: 2017
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/67005 , vital:29016 , http://books.openedition.org/obp/4209
- Description: publisher version , From Introduction: This chapter examines the importance of orality in rural communities using the paradigm of technauriture, which describes how technology, auriture2and literature intersect to transmit educational and other messages within communities. It uses oral literary research that has been conducted in the Eastern Cape region to show how technology can aid the data collection process, and how this technology can return such information to the communities from which it comes. This chapter also explores the process of orality fostered by community meetings, oral histories, oral poetry, beadwork, music and story-telling, and how this culture interacts with the recording process facilitated by modern technology. It will also consider the return of recorded oral material to educational and archival circles. These objectives are pursued using empirical data collected at Tshani near Port St. Johns, an area falling within the Mankosi tribal authority in the Eastern Cape Province of South Africa. They are also considered in relation to the work of oral poet, Bongani Sitole who lived in Mqhekezweni village near Qunu and Mthatha, as well as against the backdrop of research conducted in Keiskammahoek, and at the Broster Beadwork Collection, now housed at Walter Sisulu University in Mthatha.
- Full Text: false
- Date Issued: 2017
- Authors: Kaschula, Russell H
- Date: 2017
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/67005 , vital:29016 , http://books.openedition.org/obp/4209
- Description: publisher version , From Introduction: This chapter examines the importance of orality in rural communities using the paradigm of technauriture, which describes how technology, auriture2and literature intersect to transmit educational and other messages within communities. It uses oral literary research that has been conducted in the Eastern Cape region to show how technology can aid the data collection process, and how this technology can return such information to the communities from which it comes. This chapter also explores the process of orality fostered by community meetings, oral histories, oral poetry, beadwork, music and story-telling, and how this culture interacts with the recording process facilitated by modern technology. It will also consider the return of recorded oral material to educational and archival circles. These objectives are pursued using empirical data collected at Tshani near Port St. Johns, an area falling within the Mankosi tribal authority in the Eastern Cape Province of South Africa. They are also considered in relation to the work of oral poet, Bongani Sitole who lived in Mqhekezweni village near Qunu and Mthatha, as well as against the backdrop of research conducted in Keiskammahoek, and at the Broster Beadwork Collection, now housed at Walter Sisulu University in Mthatha.
- Full Text: false
- Date Issued: 2017
From linguistic determinism to technological determinism
- Kaschula, Russell H, Mostert, Andre M
- Authors: Kaschula, Russell H , Mostert, Andre M
- Date: 2015
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/67062 , vital:29027 , https://doi.org/10.4018/978-1-4666-5888-2.ch447
- Description: publisher version , From Introduction: This article seeks to analyse the link between linguistic determinism, the notion that language determines our thought and the way we perceive our reality, as espoused by the Sapir-Whorf hypothesis, and contemporary technological determinism. Arguably this link takes place within a global context where equal access to technology is not yet guaranteed. Ellul (1964) and Lawson’s (2004) observations create an interesting metaphor in terms of the technological beast staring down human society. The overwhelming response if we accept Lawson’s observation is complacency at best or downright naivety at worst regarding the impact of technology on our thinking. Lawson made his observation in the pre-Facebook era and subsequent literature is now much more focused on all aspects of technology within our contemporary milieu. Technology is now totally ubiquitous in the developed world and becoming more so in developing countries, albeit with a much stronger mobile bias for early technology adopters. That technology is rushing ahead of many individuals and institutions is almost an aphorism with many lagging in its wake. This lag as recognised by Brynjolfson and McAfree (2011) has wide social and economic implications for all members of society, in the case of business those that do not keep up go under. A further pertinent question revolves around how individuals who start from low technological literacy levels or do not keep pace with technological developments are impacted. Dlutu (2013) assesses for example the impact of social network sites on the isiXhosa language and culture in both a rural and urban area of South Africa. Furthermore one may then ask how this technological milieu impacts on the general aspects of the day to day lives and thinking of all members of a society. This gives rise to the concept of technological determinism which in its simplest form states ‘that technology has important effects on our lives’ (Adler, 2008, p. 537). This is far too simplistic when the contemporaneous technological developments are assessed. Adler (2008, p. 537) goes further and recognizes ‘that technology itself is socially determined…and social structures co-evolve in a non-deterministic, emergent process…the effects of any given technology depend mainly on how it is implemented which in turn is socially determined’ (Adler, 2008, p. 537). Engaging this socially determined application of technology can be advanced when the relationship with language and language determinism is considered. Moreover, it is the interplay between technology and language that gives rise to the emerging concept of a language singularity which is brought about by a form of technological determinism. This article seeks to explore the possible effects of rapid technological development on human interaction, language and culture in a ‘globalized’ world which has unequal access to literacy and technology. Furthermore, the article explores the link between language, culture, thought and technology and the type of linguistic and technological determinism that we can anticipate.
- Full Text: false
- Date Issued: 2015
- Authors: Kaschula, Russell H , Mostert, Andre M
- Date: 2015
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/67062 , vital:29027 , https://doi.org/10.4018/978-1-4666-5888-2.ch447
- Description: publisher version , From Introduction: This article seeks to analyse the link between linguistic determinism, the notion that language determines our thought and the way we perceive our reality, as espoused by the Sapir-Whorf hypothesis, and contemporary technological determinism. Arguably this link takes place within a global context where equal access to technology is not yet guaranteed. Ellul (1964) and Lawson’s (2004) observations create an interesting metaphor in terms of the technological beast staring down human society. The overwhelming response if we accept Lawson’s observation is complacency at best or downright naivety at worst regarding the impact of technology on our thinking. Lawson made his observation in the pre-Facebook era and subsequent literature is now much more focused on all aspects of technology within our contemporary milieu. Technology is now totally ubiquitous in the developed world and becoming more so in developing countries, albeit with a much stronger mobile bias for early technology adopters. That technology is rushing ahead of many individuals and institutions is almost an aphorism with many lagging in its wake. This lag as recognised by Brynjolfson and McAfree (2011) has wide social and economic implications for all members of society, in the case of business those that do not keep up go under. A further pertinent question revolves around how individuals who start from low technological literacy levels or do not keep pace with technological developments are impacted. Dlutu (2013) assesses for example the impact of social network sites on the isiXhosa language and culture in both a rural and urban area of South Africa. Furthermore one may then ask how this technological milieu impacts on the general aspects of the day to day lives and thinking of all members of a society. This gives rise to the concept of technological determinism which in its simplest form states ‘that technology has important effects on our lives’ (Adler, 2008, p. 537). This is far too simplistic when the contemporaneous technological developments are assessed. Adler (2008, p. 537) goes further and recognizes ‘that technology itself is socially determined…and social structures co-evolve in a non-deterministic, emergent process…the effects of any given technology depend mainly on how it is implemented which in turn is socially determined’ (Adler, 2008, p. 537). Engaging this socially determined application of technology can be advanced when the relationship with language and language determinism is considered. Moreover, it is the interplay between technology and language that gives rise to the emerging concept of a language singularity which is brought about by a form of technological determinism. This article seeks to explore the possible effects of rapid technological development on human interaction, language and culture in a ‘globalized’ world which has unequal access to literacy and technology. Furthermore, the article explores the link between language, culture, thought and technology and the type of linguistic and technological determinism that we can anticipate.
- Full Text: false
- Date Issued: 2015
Multilingualism and intercultural communication: a South African perspective
- Kaschula, Russell H, Maseko, Pamela, Wolff, H Ekkehard
- Authors: Kaschula, Russell H , Maseko, Pamela , Wolff, H Ekkehard
- Date: 2017
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/67015 , vital:29019 , ISBN 9781776140275 , https://muse.jhu.edu/book/52741
- Description: publisher version , To date, there has been no published textbook which takes into account changing sociolinguistic dynamics that have influenced South African society. Multilingualism and Intercultural Communication breaks new ground in this arena. Its scope ranges from macro-sociolinguistic questions pertaining to language policies and their implementation (or non-implementation), to micro-sociolinguistic observations of actual language-use in verbal interaction, mainly in multilingual contexts of Higher Education (HE). There is a gradual move for the study of language and culture to be taught in the context of (professional) disciplines in which they would be used, such as Journalism and African languages, Education and African languages, etc. The book caters for this growing market. Because of its multilingual nature, it caters to English and Afrikaans language speakers, as well as the Sotho and Nguni language groups. It brings together various inter-linked disciplines such as Sociolinguistics and Applied Language Studies, Media Studies and Journalism, History and Education, Social and Natural Sciences, Law, Human Language Technology, Music, Intercultural Communication and Literary Studies. The unique cross-cutting disciplinary features of the book will make it a must-have for twenty-first century South African students and scholars and those interested in applied language issues.
- Full Text: false
- Date Issued: 2017
- Authors: Kaschula, Russell H , Maseko, Pamela , Wolff, H Ekkehard
- Date: 2017
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/67015 , vital:29019 , ISBN 9781776140275 , https://muse.jhu.edu/book/52741
- Description: publisher version , To date, there has been no published textbook which takes into account changing sociolinguistic dynamics that have influenced South African society. Multilingualism and Intercultural Communication breaks new ground in this arena. Its scope ranges from macro-sociolinguistic questions pertaining to language policies and their implementation (or non-implementation), to micro-sociolinguistic observations of actual language-use in verbal interaction, mainly in multilingual contexts of Higher Education (HE). There is a gradual move for the study of language and culture to be taught in the context of (professional) disciplines in which they would be used, such as Journalism and African languages, Education and African languages, etc. The book caters for this growing market. Because of its multilingual nature, it caters to English and Afrikaans language speakers, as well as the Sotho and Nguni language groups. It brings together various inter-linked disciplines such as Sociolinguistics and Applied Language Studies, Media Studies and Journalism, History and Education, Social and Natural Sciences, Law, Human Language Technology, Music, Intercultural Communication and Literary Studies. The unique cross-cutting disciplinary features of the book will make it a must-have for twenty-first century South African students and scholars and those interested in applied language issues.
- Full Text: false
- Date Issued: 2017