Adsorptive removal of various phenols from water by South African coal fly ash

South African coal fly ash (SACFA) was used to effectively remove phenol, 2-nitrophenol and 4-nitrophenol from wastewater. The rate of adsorption follows first-order kinetics before attaining equilibrium with the sorption rate (Kad) obtained being the  highest for 4-nitrophenol (p-nitrophenol) (7.0 x 10.3/h), followed by phenol (1.2 x 10.3/h) and 2-nitrophenol (o-nitrophenol) (1.0 x 10.3/h). Batch studies were performed to evaluate the adsorption process, and it was found that the Freundlich isothermeffectively fits the experimental data for the adsorbates better than the Langmuir model, with the fly ash having the highest adsorption capacity of 6.51 X 10-2 mg/g for 4-nitrophenol, 6.00 x 10-2 mg/g for 2-nitrophenol and 6.31 x10-2 mg/g for phenol. The fly ash was found to adsorb 90.2% of phenol, 88.9% of 2-nitrophenol and 92.6% of 4-nitrophenol at an initialconcentration of 20 mg/.. The desorption studies suggested that the desorption of 4-nitrophenol was the most difficult of the three adsorbates to be desorbed. The desorption efficiency was 17.9% for phenol, 18.8% for 2-nitrophenol and 10.2% for 4-nitrophenol. This work proved that SACFA can be used as an efficient adsorbent material for removal of phenol from water and wastewater

Sexually transmitted infections and their diagnoses: Bapedi experience

Background: The global burden of sexually transmitted infections (STIs) is a major concern to the World Health Organization (WHO).Objective: To document STIs treated by Bapedi traditional healers and their methods of diagnoses in the Limpopo Province, South Africa. Methods: A semi-structured questionnaire with closed and open-ended questions was used to collect data from 34 traditional healers, during a face-to-face interview.Results: Five seemingly dissimilar STIs; gonorrhoea, chlamydia, HIV/AIDS, nta (Bapedi-terminology) and syphilis were identified as being treated by Bapedi traditional healers. With the exclusion of HIV/AIDS, all STIs are known by healers via their vernacular names. Not all of the recorded STIs are treated by all the questioned traditional healers. Generally, diagnosis of these infections was based primarily on the presentation of symptoms and certain behavioural traits; mostly unprotected sexual intercourse with multiple partners.Conclusion: The current study concludes that Bapedi traditional healers play an important role in the treatment STIs in the Limpopo Province. Of concern is their diagnosis which is based primarily on the presentation of symptoms and behavioural traits, which are not always accurate indicators. Thus, to make their contribution to the treatment and management of STIs beneficial, they have to receive elementary training in diagnostic methods particularly for HIV/AIDS.Keywords: Bapedi, diagnoses, Limpopo Province, sexually transmitted infections, traditional healers.African Health Sciences 2013; 13(4): 1047 - 105

Chloride-binding Effect of Blast Furnace Slag in Cement Pastes Containing Added Chlorides

Corrosion of rebar in concrete is commonly associated with, and to a large degree influenced by, the free chloride concentration in the pore water. It is standard industry practice to add various mineral admixtures such as pulverised fuel ash (PFA), or fly ash, ground granulated blast furnace slag (GGBS) and silica fume (SF), to concrete mixtures to increase the corrosion resistance of the reinforcement in the matrix and its subsequent design life span. Various investigations have reported on the effect of mineral admixtures and additions on chloride binding in cementitious matrices, and the current study contributes further to knowledge in this field. Unlike previous investigations, this study attempted to make a clear distinction between the contributions of the two components in a blended cement consisting of ordinary Portland cement (OPC) and ground blast furnace slag (BFS). These contributions of each component have been quantified. Relationships between the total amount of chloride bound, the level ofBFS additions, and the levels of initial chloride content present in the matrix were determined. It was found that the OPC/BFS blended cement with partial BFS replacements of up to 50% displayed a lower binding capacity than that of the OPC on its own. This observation was derived based on the assumption that the OPC and slag reactions were treated as competing and equivalent and did not take any potential time delays into account, nor the degree of cement hydration. The chloride-binding efficiency by the BFS is dependent on both the BFS partial replacement addition level as well as the initial amount of chloride present in the matrix. It is shown that both the OPC and BFS contribute to chloride binding in cement pastes, depending on the amount of BFS that replace the OPC component in the matrix.Keywords: Chloride binding, granulated blast furnace slag, pore solution, permeability, corrosio

Use, conservation and present availability status of ethnomedicinal plants of Matebele-Village in the Limpopo Province, South Africa

Ethnobotanical surveys were carried out between January 2011 and April 2012 to compile an inventory of plants used medicinally by people of the Matebele village. A semi-structured questionnaire was used to collect data on the species used by the villagers. The results show that 65 species (86.1% indigenous and 13.8% exotics) from 36 families, mostly the Asteraceae (13.8%) and Fabaceae (10.7%), are being used to treat 28 ailments or conditions. To the best of our knowledge, 24.4% of the species were recorded for the first time as medicinal. The most widely used species were Terminalia sericea (43.3%), followed by Acacia senegal, Eucomis pallidiflora (36.6% each), Drimia elata (26.6%), Warburgia salutaris (19.9%) and Artemisia afra (16.6%). Roots (39.1%), leaves (21.6%) and stem bark (10.8%) were the most frequently used parts. The heavy dependence on wild medicinal plants and utilization of threatened (E. pallidiflora, D. elata and W. salutaris) and protected (Sclerocarya birrea) species by inhabitants of Matebele village calls for urgent conservation intrusion.Keywords: Ethnomedicinal plants, Limpopo Province, Matebele Village, conservation, present availability status, South Africa, useAfrican Journal of Biotechnology Vol. 12(18), pp. 2392-240

Exotic and indigenous problem plants species used, by the Bapedi, to treat sexually transmitted infections in Limpopo Province, South Africa

Background: The ethnic usage of exotics and indigenous problem plants is a highly debated topic, as legislative requirements over-shadow their potential medicinal value, particularly to treat sexually transmitted  infections (STIs). Limited information exists regarding their medicinal value among the Bapedi.Objective: To ascertain the importance of exotics and indigenous problem plants in the treatment of STIs, a major global primary health care challenge.Methods: A field observation and semi-structured questionnaire focussing on species diversity, types of STIs treated and medicinal preparation as well as application was used to collect data from 34 traditional healers.Results: Seven exotics and three indigenous problem species were  identified. These species were used to treat four STIs; with Catharanthus roseus illustrating its dominance in the treatment of gonorrhoea. Some medicinal species used by Bapedi traditional healers have been validated through scientific research or through their extensive use by various  cultures in South Africa and other parts of Africa. To the best of our  knowledge Alternanthera pungens, Caesalpinia decapetala, Cinnamomumverum, and Citrullus lanatus are reported for the first time in the treatment of the investigated STIs.Conclusion: Exotic and indigenous problem species constitute an important component of the STIs treatment protocol. Their utilization by Bapedi cautions against the narrow-minded approach of indiscriminate eradication, as these species can play a significant role in the primary health care needs of socio-economic vulnerable people.Keywords: Bapedi, exotics, indigenous problem plants, sexually transmitted infections

The Corrosion Behaviour of WC-Co-Ru Alloys in Aggressive Chloride Media

Hardmetals possess excellent wear resistance, making them suitable alloys in several industrial applications. Mine waters with both dissolved chloride and sulphate salts can be severely corrosive and can limit the application of hardmetal tools in the mining industry. Ru additions to these alloys can refine and improve selected mechanical properties, but its influence on the corrosion resistance is unknown. A series of WC-Co-Ru alloys was evaluated in different chloride containing media to investigate their corrosion resistance. Standard electrochemical corrosion tests, chronoamperometric measurements, and surface analyses with Raman spectroscopy were conducted. An increasing amount of Ru improves the corrosion resistance of all the alloys. The effect is not as dramatic as that observed with stainless steels containing Ru in corrosive media. In both corrosive media Ru decreased the cathodic Tafel constant and has a retarding influence on the cathodic part of the corrosion reaction. Raman analyses indicated the presence of tungsten oxide, hydrated tungsten oxide compounds, and CoO and Co3O4 formed on the alloy surfaces during the corrosion process

Phytomedicine versus Gonorrhoea: The Bapedi Experience

Records regarding the phytomedicine employed by the Bapedi are almost non-existent. This is the first study of herbal remedies used by Bapedi traditional healers to treat gonorrhoea, of concern as it is a danger to reproductive health. A semi-structured questionnaire, centred on sexual health, was administered to 30 traditional healers in 15 local municipalities across the three districts of Limpopo Province during 2009/10. The questionnaire focussed on the use of plants for medicine as well their application in reproductive health management. This investigation found that the Bapedi employed no less than 18 different plant species, sometimes as multiple-plant extracts, but more often as single-plant extracts. The single most used species was Catharanthus roseus, which accounted for 60% of all reported cases, followed by Aloe marlothii subsp. marlothii (13.3%). Both these species occur abundantly throughout the province and are currently not threatened. This is the first record for the use of Callilepis salicifolia, Jatropha zeyheri and Cotyledon orbiculata to treat gonorrhoea by people of any culture

Effectiveness of Selective Catalytic Reduction (SCR) systems on reducing gaseous emissions from an engine using Diesel and Biodiesel Blends

The aim of this investigation was to quantify organic and inorganic gas emissions from a four-cylinder diesel engine equipped with a urea selective catalytic reduction (SCR) system. Using a bench dynamometer, the emissions from the following mixtures were evaluated using a Fourier transform infrared (FTIR) spectrometer: low-sulfur diesel (LSD), ultralow-sulfur diesel (ULSD), and a blend of 20% soybean biodiesel and 80% ULSD (B20). For all studied fuels, the use of the SCR system yielded statistically significant (p < 0.05) lower NOx emissions. In the case of the LSD and ULSD fuels, the SCR system also significantly reduced emissions of compounds with high photochemical ozone creation potential, such as formaldehyde. However, for all tested fuels, the SCR system produced significantly (p < 0.05) higher emissions of N2O. In the case of LSD, the NH3 emissions were elevated, and in the case of ULSD and B20 fuels, the non-methane hydrocarbon (NMHC) and total hydrocarbon of diesel (HCD) emissions were significantly higher

Intraocular lenses in age-related macular degeneration

Purpose: The aim of this work is to review the lenses, assessing their advantages and disadvantages. We describe a total of seven types of intraocular lenses (IOLs) recommended for age-related macular degeneration (AMD). Methods: We used the PubMed web platform to search for implantable devices in various stages of AMD. We searched for both prospective and retrospective studies and also case reports. Results: Clinical results in AMD patients have been described for a total of seven types of IOLs recommended for AMD: an implantable miniature telescope (IMT), IOL-VIP System, Lipshitz macular implant (LMI), sulcus-implanted Lipshitz macular implant, LMI-SI, Fresnel Prism Intraocular Lens, iolAMD and Scharioth Macula Lens. Conclusions: We conclude that to objectively ascertain the effectiveness and safety of these lenses, further independent clinical studies with longer follow-up data are necessary prior to the general use of these optical devices