495 research outputs found
Stuck in neutral: A case study of the challenges facing the Kenyan automotive sector
Successful industrialisation strategies have helped many developing countries transform the structure of their economies, enhance productivity and boost economic growth. Prioritising which industrial sectors to develop, and how, is paramount given scarce financial resources, skills shortages and limited technological capabilities. Although still a developing country, Kenya has the most advanced economy among her regional peers. Kenya's small automotive sector was established four decades ago with the support of import substitution industrialisation (ISI) policies. However, following liberalisation of the economy in the last decade of the 20th century, domestic industries were suddenly exposed to competition from imported products. On one hand this blunted prospects for faster development of manufacturing capabilities, but on the other, imports provided consumers with affordable alternatives. As a result, the domestic automobile assembly sector faces ongoing competition from used passenger vehicle imports. Fundamentally, the sector lacks access to a sizeable market, which inhibits attraction of large-scale investments necessary for upgrading. Market attributes aside, this study found several other challenges confronting the sector. These are; the absence of a national automotive strategy, incoherent policy decisions and ineffective regional integration which has hampered growth beyond national borders. Additionally, weak support for higher levels of domestic value addition in the auto components and motorcycle sectors has been exacerbated by fierce competition from Asian producers. Recent interventions to restart passenger vehicle assembly have only spurred superficial development notwithstanding some government support. The challenges facing late industrialisers are multi-dimensional with near term solutions difficult to discern - the small Kenyan automotive sector is emblematic of this
Establishment of background radiation dose rate in the vicinity of the proposed Manyoni Uranium Project, Singida
The absorbed dose rate in air in the vicinity of the proposed Manyoni uranium mining project located in Singida region, Tanzania, was determined so as to establish the baseline data for background radiation dose rate data prior to commencement of uranium mining activities. Twenty stations in seven villages were selected and monitored for six months from June 2012 to November 2012. The absorbed dose rate in air was measured by means of CaF2:Dy thermoluminescent dosimeters (TLD-200). The annual effective dose was estimated using outdoor occupancy factor of 0.2 and conversion coefficient factor of 0.7 SvG y-1. The mean dose rate was found to range from 16.68 - 507.00 nGy h-1 with an average of 74.86 nGy h-1. Maximum average dose rate of 396.7 nGy h-1 was found at station number 8 situated in Mwanzi Village which was about 7 times higher than the world average value of 59 nGy h-1 (UNSCEAR 2008) corresponding to annual effective dose of 0.5mSv y-1. This value is 2 fold lower than the recommended limit of 1 mSv y-1 for a member of the public (ICRP 1990). Minimum avarage dose rates of 30.9 nGy h-1 was found in station number 16 and 17 located in Aghondi village, corresponding to annual effective dose of 0.04 mSv y-1. This implies that prior to commencement of uranium mining activities in the proposed area the external exposure rates due to the natural background radiation are lower than the world recommended value.Keywords: Absorbed dose rate, Uranium mining, Background radiation, Thermoluminescent dosimeter, Annual effective dos
Viewpoint: Environmental Education Curriculum Policy in Tanzanian Schools
This viewpoint paper examines environmental education policy in practice in Tanzania in the context of the primary school curriculum. This policy review stretches back to the mid-1960s, when major curricula changes were effected, to the present. The paper highlights efforts during this period to provide relevant education and enhance development of environmental education skills as well as life skills for school candidates and community members. This paper provides background information and highlights several issues associated with current policies in operation, including interpretations of policy and implementation. It identifies some of the key achievements and makes recommendations for strengthening the implementation of policy in practice. A number of relevant documents were drawn on in this study, augmented by field observations. The study found that the school curriculum, which is the vehicle for translating policy into actions is not adequately implemented due to poor defining of environmental education in early policy documents
Effects of Social Media access on Learning in Secondary Schools, in Kinondoni Municipality, Tanzania
Social media is rapidly changing the communication setting of day-to-day activities of young people. The presence of social media has ominously influenced the academic life of students. Social media is used to fulfill perceived social needs, but social media cannot fulfill all needs. Institutions and academicians are continually trying social media technologies hoping to excite critical thinking skills, associations, and knowledge construction. This study intended to explore and examine the effects of social media access on learning in secondary schools in Kinondoni Municipality in the city of Dar es Salaam based on the following specific objectives: i) to investigate the effects of Facebook on students learning in secondary schools in Kinondoni Municipality ii) to determine the effects of WhatsApp usage to students learning and attitude, in Kinondoni Municipality with relationship to their time management iii) to establish the effects of Instagram on change of student behavior in secondary school, in Kinondoni Municipality and iv) to explore how YouTube contributes to the moral development of secondary school students in Kinondoni Municipality. The study employed a mixed-method design in examining these effects. Five hundred and fifty (550) participants were conveniently sampled and heads of schools were interviewed within a week. After studying the phenomena that were of interest to the study, and transcribing the various responses of the participants the results revealed that social media is widely used by secondary school students for non-beneficial activities and less used for gaining subject knowledge and acquiring learning basis. Surprisingly, however, participants were in support of the idea that social media access to students contributes a significant quota to their academy based on basis of belongingness. It concluded and recommended that, to the leaders, policy regarding social media to students should be amended to support the view that teachers can have the ability to teach students better ways they can use available social media. To the bloggers, it is recommended that the communication authority, TCRA should restrict those Bloggers who share and publish unwanted, unethical material and morally threatening content to youth. The content among others includes “UtamuRaha”, “Bongo Sex” and such porn content that students have access to. To the practitioners, the study recommends that teachers in schools should make sure that they keep a close eye on students' changes in behavior. Elements of homosexual behaviour and other forms of Internet-learned behaviour in school demonstrates the failure of close supervision of students use of media. We recommend that psychotherapy and guidance should be regularly provided by school teachers to lead students in achieving school goals and divert them from these behaviors. We also recommend that TCRA should block unsuitable content from school-based internet to keep students out of danger and help them to use the appropriate internet sites for serious learning and character formation. Keywords: Social media access, students learning. DOI: 10.7176/JEP/13-24-03 Publication date:August 31st 2022
Densification Behaviour and Structural Properties of Niobium and Lanthanum-doped Lead Zirconate Titanate and Lead Barium Zirconate Ferroelectrics for Low-donor Dopants Concentrations
In this paper we report the densification behaviour and structural properties of niobium and lanthanum-doped lead zirconate titanate (PZT) and lead barium zirconate (PBZ) ferroelectrics for low additive concentrations (0-2%).The PZT materials were calcined at 800 oC and sintered at 1200 oC while the PBZ materials were calcined at 850 oC and sintered at 1250 oC. Densification behaviour revealed that materials with lanthanum or niobium additives of greater than 0.5% for PZT and 0.2% for PBZ achieved complete densification. A strong distortion was observed in lattice parameters for lower dopants in which PBZ doped materials showed higher lattice distortions than PZT doped materials. The grain sizes decreased with increasing dopants concentrations for PZT while it increased with increasing dopants concentrations for PBZ materialsKeywords: Densification; structural; low level donor dopants; ferroelectrics; sintering
Assessment of concentrations of trace and toxic heavy metals in soil and vegetables grown in the vicinity of Manyoni uranium deposit in Tanzania
This study reports on determination of concentrations of trace and toxic heavy metals in soil and vegetables grown near of Manyoni uranium deposit. Soil and vegetable samples were collected from five sites namely Mitoo Mbuga, farming area, Miyomboni, Tambukareli and near water pump. The concentrations of heavy metals in soil and edible vegetables samples were analyzed using Energy Dispersive X-ray Fluorescence Spectrometry (EDXRF).All vegetable samples were found to have higher concentrations (in μg/g) of trace elements such as Ni (67.3) in pea leaves, Cu (14.9) in pumpkin leaves, Fe (478.6), (200.5) and (337.1) in pea, pumpkin and spinach leaves respectively, than the maximum tolerable limits recommended by WHO/FAO. Mean concentration of Pb (1.6 μg/g) in pumpkin leaves collected from Miyomboni (area D) were observed to be higher than the safe limit of (0.3μg/g) set by Codex 2006. Toxic elements concentrations (in μg/g) such as Cd (10.4), Pb (23.2),Hg (4.1), Th (31.5) and U (23.9) were observed to be high in soil collected from Mitoo Mbuga and farming area. Therefore, vegetables in the vicinity of Manyoni uranium deposit can expose people to toxic elements which are detrimental to their health. A more detailed study involving other foodstuffs is needed to establish conclusive results.Keywords: Soil, vegetables, Manyoni Uranium Deposit, Toxic Elements, EDXR
Assessment of indoor radon-222 concentrations in the vicinity of Manyoni uranium deposit, Singida
This study aimed to assess indoor radon concentrations in the vicinity of the Manyoni Uranium Deposit in Singida. The concentrations were measured for two months in 32 houses in the vicinity of Manyoni Uranium Deposit and 9 houses at Manyoni town using a portable radon gas monitor (Alpha –GUARDTM). The radon concentrations ranged from 27±3 to 518±28 Bq/m3with the overall mean of 166±12 Bq/m3 which is above recommended values of 100 Bq/m3 and 148 Bq/m3 set by WHO (World Health Organization) and EPA (Environmental Protection Agency's), respectively. The overall mean of indoor radon concentrations from each village were Kipondoda (169±13 Bq/m3), Muhalala (177±16 Bq/m3), Mwanzi, (287±13 Bq/m3), Mitoo (325±21 Bq/m3) and Majengo (377±23 Bq/m3) which exceed the limit set by WHO (World Health Organization) and EPA (Environmental Protection Agency). The value of 325±21 Bq/m3 and 377±23 Bq/m3 from Mitoo and Majengo respectively, exceed the limit of 300 Bq/m3 recommended by ICRP (International Commission on Radiation Protection). Thus there is a non-negligible probability of incurring stochastic effects for people living in the vicinity of Manyoni Uranium mine. It is recommended that human activities should be controlled near the uranium deposits and dwelings should be well ventilated.Keywords: Indoor radon, Concentrations, Cancer, Manyoni uranium deposit, Alpha –GUAR
Studies on Animal Health Delivery Systems in Pastoral Areas in Manyara, Tanzania
A study to identify animal health delivery systems to show how marginalized pastoral communities are accessing animal health services was conducted in Babati, Hanang and Mbulu Districts of Manyara Region. It was shown that livestock was the principal economic activity for pastoralists in Mbulu, Babati and Hanang and that pastoralists are located in relatively remote areas. Animal diseases, in particular parasitic infections, viral/bacterial epizootics and scarcity of water and pasture are among the major constraints that these pastoralists face. Despite of such problems, reliable animal health delivery system lacks in these areas and handling of almost all animal husbandry services, treatment and control of diseases is exclusively carried out by farmers that are quite skilful home grown animal para-veterians. Efforts to improve animal health and productivity and thus economy and livelihood of these pastoral farmers will succeed through their involvement in solving the problems. It was observed that there is a high illiteracy rate among the pastoralists; hence education for all is essential for success of any developmental project to be implemented in the pastoral areas. In summary the information available in the present study validates the need for planning of an effective and sustainable animal health delivery system in the pastoral farming systems in Manyara region and Tanzania as a whole
Determination of radon gas and respirable ore dust concentrations in the underground merelani Tanzanite mines
This study has estimated the concentrations of radon gas and respirable ore dust in the Merelani underground tanzanite mines. Two different portable monitors were used to measure the radon gas and respirable ore dust concentrations respectively. The mean radon gas concentration (disintegrations per second per cubic meter) ranges from 40.1 Bq/m3 to 4.2x103 Bq/m3 with the geometric mean of 118.4 Bq/m3 which is below the ICRP workplace guidance level of 500 - 1500 Bq/m3. The estimated mean annual effective dose (D) was 1.6 mSv which is significantly lower than the external exposure annual effective dose of 20 mSv and the annual organ dose limit of 2.4 mSv. The overall concentrations of respirable ore dust arithmetic mean was 18.2 g/m3 and the geometric mean of 2.1 g/m3 which is very high compared to the guidance level of 2 g/m3. The respirable dust was mainly produced during drilling and blasting of rocks, under normal conditions the geometric mean of respirable gas concentrations was 0.8 g/m3. It is recommended that immediate intervention such as providing proper ventilation during the two processes to dilute radon levels in underground mines and the monitoring should be done regularly
Assessment of radioactivity levels in coal and coal ash in Kiwira coal mine using gamma-ray spectrometry
This study aimed to assess the radioactivity levels and associated dose rates from the naturally occurring radionuclides 226Ra, 232Th and 40K in coal and coal ashes at Kiwira coal mine. The radioactivity of 40 representative coal, fly ash samples were measured using gamma spectroscopy of the Tanzania Atomic Energy Commission (TAEC) in Arusha, Tanzania. The activity concentrations of 226Ra, 232Th and 40K in coal and coal ashes from Kiwira were higher by several orders of magnitude than their worldwide average values. The calculated radium equivalent activity, the air absorbed dose rate, external hazard index and the average annual effective dose rate in fly ashes were 1335 ± 60 Bq kg-1, 610 ± 29 nGy h-1, 4 ± 0.4, 738 ± 52 µSv y-1 which were higher than the international recommended values of 370 Bq kg-1, 57 nGy h-1, and 70 µSv y-1 for fly-ashes respectively. The results provide information for the radiation protection when the coal and its by-products in the vicinity of Kiwira coal field is used. The data can be used by the authorities to design an appropriate method for handling wastes and implement intervention measures to protect the miners, the public as well as the environment.Keywords: Coal, fly ash, soil, radioactivity, gamma-ray spectrometr
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