scholarly journals Thermal and mechanical characteristics of local firewood species and resulting charcoal produced by slow pyrolysis

Author(s):  
Michael Lubwama ◽  
Vianney Andrew Yiga ◽  
Ivan Ssempijja ◽  
Harriet Nalubega Lubwama

AbstractThe main source of fuel for domestic cooking applications in Sub-Saharan Africa is either locally available firewood species or charcoal produced by slow pyrolysis of these species. However, very few studies exist that characterize and quantify physical properties, burning rates, peak temperatures, and calorific values of typical firewood species and resulting charcoal fuels produced by slow pyrolysis. This study evaluated the mechanical and thermal properties of firewood and charcoal from five tree species namely: Dichrostachys cinerea, Morus Lactea, Piliostigma thonningii, Combretum molle, and Albizia grandibracteata. Characterization was done by scanning electron microscopy, thermogravimetric analysis, bomb calorimetry, Fourier transform infrared spectroscopy, bulk density measurements, and durability, water boiling and absorption tests. SEM images showed the development of macropores on charcoal after slow pyrolysis. Peak temperatures during firewood and charcoal combustion ranged between 515.5–621.8 °C and 741.6–785.9 °C, respectively. Maximum flame temperatures ranged between 786.9–870.8 °C for firewood and 634.4–737.3 °C for charcoal. Bulk densities and calorific values of charcoal species were higher than those for firewood species. Drop strengths for firewood were all 100% while for charcoal were between 93.7 and 100%. Water boiling tests indicated that firewood fuel performed better that charcoal fuel for low amounts of water due to higher maximum flame temperatures obtained during combustion of firewood.


2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Poyodi Kola ◽  
Kossi Metowogo ◽  
Yendubé T. Kantati ◽  
Povi Lawson-Evi ◽  
Mabozou Kpemissi ◽  
...  

Cancer is an emerging public health problem in sub-Saharan Africa. Several medicinal plants are used by traditional healers to treat tumors. In Togo, there are no recorded data for these plants but traditional healers claim to cure tumors with some success. So, information on medicinal plants used to cure human tumors and cancer could be of great importance for their widespread use and scientific validation. The present ethnopharmacological survey aims to record information on antitumor plants in central and Kara regions of Togo. Semistructured validated questionnaires were administered to fifty-seven traditional healers specialized in tumor management in 7 prefectures of Togo. Good practices and know-how were recorded. Quantitative ethnobotanical tools were used to analyze and summarize the data collected. 85 recipes of medicinal plants for tumors management are provided. In the local dialect, 78.95% of traditional healers do not have a clear tumor designation and 29.90% find that the causes of tumors remain unknown. According to 48.78% of traditional healers, the diagnosis of tumors in patients is made in the hospital. The types of tumors frequently treated are those of the breast (43.75%) and the lung (16.67%). The seventy listed medicinal plants belong to thirty-nine families, the most represented being Rubiaceae (17.95%), Caesalpiniaceae (12.82%), Fabaceae (10.26%), and Annonaceae (7.69%). The ten most cited species were Xylopia aethiopica, Aframomum melegueta, Khaya senegalensis, Parkia biglobosa, Piliostigma thonningii, Blighia sapida, Vitellaria paradoxa, Adansonia digitata, Annona muricata, and Parinari curatellifolia. Most of the recipes are prepared as decoction (40%) and administered orally (54.12%). Both regions of our study have a wealth of medicinal plants, and traditional healers would use their local knowledge in the management of various tumors and chronic wounds.



2017 ◽  
Vol 1 (6) ◽  
pp. 533-537
Author(s):  
Lorenz von Seidlein ◽  
Borimas Hanboonkunupakarn ◽  
Podjanee Jittmala ◽  
Sasithon Pukrittayakamee

RTS,S/AS01 is the most advanced vaccine to prevent malaria. It is safe and moderately effective. A large pivotal phase III trial in over 15 000 young children in sub-Saharan Africa completed in 2014 showed that the vaccine could protect around one-third of children (aged 5–17 months) and one-fourth of infants (aged 6–12 weeks) from uncomplicated falciparum malaria. The European Medicines Agency approved licensing and programmatic roll-out of the RTSS vaccine in malaria endemic countries in sub-Saharan Africa. WHO is planning further studies in a large Malaria Vaccine Implementation Programme, in more than 400 000 young African children. With the changing malaria epidemiology in Africa resulting in older children at risk, alternative modes of employment are under evaluation, for example the use of RTS,S/AS01 in older children as part of seasonal malaria prophylaxis. Another strategy is combining mass drug administrations with mass vaccine campaigns for all age groups in regional malaria elimination campaigns. A phase II trial is ongoing to evaluate the safety and immunogenicity of the RTSS in combination with antimalarial drugs in Thailand. Such novel approaches aim to extract the maximum benefit from the well-documented, short-lasting protective efficacy of RTS,S/AS01.



1993 ◽  
Vol 47 (3) ◽  
pp. 555-556
Author(s):  
Lado Ruzicka


1987 ◽  
Vol 87 (1) ◽  
pp. 118-142


Crisis ◽  
2011 ◽  
Vol 32 (1) ◽  
pp. 43-51 ◽  
Author(s):  
Eugene Kinyanda ◽  
Ruth Kizza ◽  
Jonathan Levin ◽  
Sheila Ndyanabangi ◽  
Catherine Abbo

Background: Suicidal behavior in adolescence is a public health concern and has serious consequences for adolescents and their families. There is, however, a paucity of data on this subject from sub-Saharan Africa, hence the need for this study. Aims: A cross-sectional multistage survey to investigate adolescent suicidality among other things was undertaken in rural northeastern Uganda. Methods: A structured protocol administered by trained psychiatric nurses collected information on sociodemographics, mental disorders (DSM-IV criteria), and psychological and psychosocial risk factors for children aged 3–19 years (N = 1492). For the purposes of this paper, an analysis of a subsample of adolescents (aged 10–19 years; n = 897) was undertaken. Results: Lifetime suicidality in this study was 6.1% (95% CI, 4.6%–7.9%). Conclusions: Factors significantly associated with suicidality included mental disorder, the ecological factor district of residence, factors suggestive of low socioeconomic status, and disadvantaged childhood experiences.



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