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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Bioprocess development for removal of nitrogenous compounds from precious metal refinery wastewater

Manipura, Walappuly Mudiyanselage Janakasiri Aruna Shantha Bandara January 2008 (has links)
Removal of nitrogenous compounds from precious metal refinery (PMR) wastewater is important in terms of avoiding eutrophication (environmental protection), metal recovery (increased overall process efficiency and value recovery) and reuse of treated water (maximum use of natural resources). Extreme pH conditions (4 to 13 depending on the wastewater stream), high chemical oxygen demand (> 10,000 mg/I), numerous metals and high concentrations of those metals (> 20 mg/l of platinum group metals) in the wastewater are the main challenges for biological removal of nitrogenous compounds from PMR wastewater. Nitrogenous compounds such as NH₄⁺-N and N0₃-N are strong metal ligands, which make it difficult to recover metals from the wastewater. Therefore, a bioprocess was developed for removal of nitrogenous compounds from carefully simulated PMR wastewater. A preliminary investigation of metal wastewater was carried out to determine its composition and physico-chemical properties, the ability to nitrify and denitrify under different pH conditions and denitrification with different carbon Source compounds and amounts. Even at pH 4, nitrification could be carried out. A suitable hydraulic retention time was found to be 72 hours. There was no significant difference between sodium acetate and sodium lactate as carbon sources for denitrification. Based on these results, a reactor comparison study was carried out using simulated PMR wastewater in three types of reactors: continuously stirred tank reactor (CSTR), packed-bed reactor (PBR) and airlift suspension reactor (ALSR). These reactors were fed with 30 mg/l of Rh bound in an NH₄⁺ based compound (Claus salt: pentaaminechlororhodium (III) dichloride). Total nitrogen removal efficiencies of > 68 % , > 79 % and > 45 % were obtained in the CSTR, PBR and ALSR, respectively. Serially connected CSTR-PBR and PBR-CSTR reactor configurations were then studied to determine the best configuration for maximum removal of nitrogenous compounds from the wastewater. The PBR-CSTR configuration gave consistent biomass retention and automatic pH control in the CSTR. Ammonium removal efficiencies > 95 % were achieved in both reactors. As poor nitrate removal was observed a toxicity study was carried out using respirometry and the half saturation inhibition coefficients for Pt, Pd, Rh and Ru were found to be 15.81, 25.00, 33.34 and 39.25 mg/l, respectively. A mathematical model was developed to describe the nitrogen removal in PMR wastewater using activated sludge model number 1 (ASMl), two step nitrification and metal toxicity. An operational protocol was developed based on the literature review, experimental work and simulation results. The optimum reactor configuration under the set conditions (20 mg/I of Rh and < 100 mg/I of NH₄⁺-N) was found to be PBR-CSTR-PBR process, which achieved overall NH₄⁺-N and N0₃⁻-N removal efficiencies of > 90 % and 95 %, respectively. Finally, a rudimentary microbial characterisation was carried out on subsamples from the CSTR and PBRsecondary. It was found that the CSTR biomass consisted of both rods and cocci while PBRsecondary consisted of rods only. Based on these experimental works, further research needs and recommendations were made for optimisation of the developed bioprocess for removal of nitrogenous compounds from PMR wastewater.
22

Hepatitis C and human immunodeficiency virus infections in injecting drug users in drug treatment centers in Vietnam.

Phan, Ha Thi Thu. Mullen, Patricia D., Williams, Mark L., January 2009 (has links)
Source: Dissertation Abstracts International, Volume: 70-03, Section: B, page: 1572. Adviser: Lu-Yu Hwang. Includes bibliographical references.
23

An environmental impact perspective of the management, treatment, and disposal of hazardous pharmaceutical compounds generated as medical waste at selected hospitals in Cape Town, South Africa

Sattar, Mohamed Shaheen January 2011 (has links)
Thesis (MTech (Environmental Health))--Cape Peninsula University of Technology, 2011. / Pharmaceuticals have been formulated to influence physiological systems in humans, animals, and microbes but have never been considered as potential environmental pollutants by healthcare professionals. The human body is not a barrier to chemicals, but is permeable to it. Thus after performing their in-vivo functions, pharmaceutical compound introduced into the body, exit mainly via urine and faeces. Sewage therefore contains highly complex mixtures of chemicals in various degrees of biological potency. Sewage treatment works including those in South Africa, on the other hand, are known to be inefficient in removing drugs from sewage and consequently either the unmetabolised pharmaceutical compounds or their metabolites emerge in the environment as pollutants via several trajectories. In the environment, the excreted metabolites may even undergo regeneration to the original parent molecule under bacterial influence, resulting in "trans-vivo-pharmaceutical-pollution-cycles". Although all incinerators are known to generate toxins such dioxins and furans from the drugs they incinerate, all the medicines disposed by the hospitals under research, were incinerated, as the preferred option of disposal. The incineration process employed was found to be environmentally unsafe. Expired and unused medicines which the general public discard as municipal solid waste become landfilled. Because many landfill sites are not appropriately engineered, the unwanted drugs landfilled therein, leach into the surrounding ground water, which is the influent source of water treatment plants. Water treatment plants, including those in South Africa, are also inefficient in eliminating pharmaceutical compounds, releasing them in sub-therapeutic concentrations into potable tap water as pollutants, the full effects of which are yet to be determined.
24

Behandelingsbehoeftes van Heroïenafhanklikes met spesiale verwysing na SANRA Kliniek, Witbank

Opperman, Hester Catharina 30 June 2006 (has links)
The motivation for this study is the increase of treatment needs of heroin dependents at SANCA, (South African National Council of Alcohol and Drug Abuse) Witbank. SANCA Witbank wants to ensure that the most effective treatment can be supplied. Research goals are to: &#61656; Do a literature study of out-patient treatment programmes. &#61656; Assess the needs of heroin out-patient dependents with regard to out-patient treatment programmes. &#61656; Make recommendations with regard to out-patient treatment programmes for heroin dependents. It was an exploratory research subject and the data collection methods were qualitative and quantitative. Interview schedules were used as research tools. Schedule B was completed by the researcher with heroin dependents that visited SANCA Witbank for the period 31 January 2005 to 4 February 2005. Schedule A was completed by the researcher with personnel of SANCA out-patient clinics and the questions were discussed and completed telephonically. The conclusion is that the treatment programme of SANCA Witbank is in line with the rest of the drug dependent field and only minimal recommendations were made. / Social Work / MA(SS)(MENTAL HEALTH)
25

An environmental impact perspective of the management, treatment, and disposal of hazardous compounds generated as medical waste at selected hospitals in Cape Town, South Africa

Sattar, Shaheen January 2013 (has links)
Thesis (MTech(Environmental Health))--Cape Peninsula University of Technology, 2011. / Pharmaceuticals have been formulated to influence physiological systems in humans, animals, and microbes but have never been considered as potential environmental pollutants by healthcare professionals. The human body is not a barrier to chemicals, but is permeable to it. Thus after performing their in-vivo functions, pharmaceutical compound introduced into the body, exit mainly via urine and faeces. Sewage therefore contains highly complex mixtures of chemicals in various degrees of biological potency. Sewage treatment works including those in South Africa, on the other hand, are known to be inefficient in removing drugs from sewage and consequently either the unmetabolised pharmaceutical compounds or their metabolites emerge in the environment as pollutants via several trajectories. In the environment, the excreted metabolites may even undergo regeneration to the original parent molecule under bacterial influence, resulting in “trans-vivo-pharmaceutical-pol ution-cycles”. Although all incinerators are known to generate toxins such dioxins and furans from the drugs they incinerate, all the medicines disposed by the hospitals under research, were incinerated, as the preferred option of disposal. The incineration process employed was found to be environmentally unsafe. Expired and unused medicines which the general public discard as municipal solid waste become landfilled. Because many landfill sites are not appropriately engineered, the unwanted drugs landfilled therein, leach into the surrounding ground water, which is the influent source of water treatment plants. Water treatment plants, including those in South Africa, are also inefficient in eliminating pharmaceutical compounds, releasing them in sub-therapeutic concentrations into potable tap water as pollutants, the full effects of which are yet to be determined.
26

Exploring the perceived effectiveness of cognitive behavioural therapy as a treatment model for substance use disorders with co-occurring disorders at substance abuse rehabilitation centres in Gauteng

Mhlungu, Sabelo Albert 02 1900 (has links)
Text in English / Against the background of high prevalence of substance abuse in the globe generally and South Africa in particular, research has shown an association between substance abuse and other mental disorders or vice-versa. With most rehabilitation centres offering separate diagnosis and treatment for the two disorders, the problem of relapse has been significant. The purpose of this study is to explore the perceived effectiveness of CBT as a treatment model for substance use disorders with co-occurring disorders. Subsequently, the research will add to the already existing research evidence. The study was conducted in five rehabilitation centres in Gauteng Province. The qualitative descriptive research approach was used to conduct the study. Both purposive and snowball sampling were used to recruit participants in this study. The sample consisted of CBT specialist participants from diverse race, gender, ethnicity, and age ranging from 30 to 65 years, with at least a minimum of five years’ experience. A pilot study with two specialist participants was conducted, and this enhanced trustworthiness and authenticity of the study. The primary method of qualitative data collection employed in this study was semi-structured individual interviews for specialist participants. Grounded theory analysis was employed to analyse data. The findings of the study emphasised a need to not separate treatment of substance use disorders and psychiatric pathologies. More importantly, the effectiveness of CBT in treating both disorders was established by the study. The study further encourages more time in therapy as the way to increase effective results accompanied by less relapse rate. Accordingly, the findings of this study encourage more research and use of CBT treatment for substance use disorders with co-occurring disorders in South Africa. This study found that the most used substances are both legal and illegal, and they are further classified as depressants, stimulants, opioids, and new psychoactive substances. A vulnerable population to abuse substances includes adolescent and young adults, individuals with co-occurring disorders, and low socio-economic status. The disorders that normally co-exist with substance use disorder ranges from depression, bipolar disorder, schizophrenia, sleeping disorder, impulsivity, antisocial behaviour, borderline disorder, paranoia, panic disorder, and suicide behaviour. The study found that genetic predisposition, depression, parental neglect and financial problems, experimentation with substances for relaxation, peer group pressure, and co-occurring disorders are high risk causes for substance abuse. The experience of participants in treating substance use disorder with co-occurring disorders involves which disorders get treated first, and the mental state of patients for effective treatment. The various substance abuse treatment models includes person centred approach, bio-psychosocial approach, holistic approach, eclectic therapy, integrated approach, resilient approach, rational emotive behavioural therapy, family therapy, motivational interviewing, 12-step programme, and cognitive behavioural therapy. The participants’ experience with CBT entails its usability in both individual and group therapy, the use of CBT skills after therapy, and CBT effectiveness in relapse prevention. Accessibility and affordability of CBT treatment is influenced by access to rehabilitation centres and cost of rehabilitation centres. Lastly, individual factors, family factors, and environmental factors are part of the contributing factors towards high relapse rates. / Psychology / M.A. (Psychology)
27

Behandelingsbehoeftes van Heroïenafhanklikes met spesiale verwysing na SANRA Kliniek, Witbank

Opperman, Hester Catharina 30 June 2006 (has links)
The motivation for this study is the increase of treatment needs of heroin dependents at SANCA, (South African National Council of Alcohol and Drug Abuse) Witbank. SANCA Witbank wants to ensure that the most effective treatment can be supplied. Research goals are to: &#61656; Do a literature study of out-patient treatment programmes. &#61656; Assess the needs of heroin out-patient dependents with regard to out-patient treatment programmes. &#61656; Make recommendations with regard to out-patient treatment programmes for heroin dependents. It was an exploratory research subject and the data collection methods were qualitative and quantitative. Interview schedules were used as research tools. Schedule B was completed by the researcher with heroin dependents that visited SANCA Witbank for the period 31 January 2005 to 4 February 2005. Schedule A was completed by the researcher with personnel of SANCA out-patient clinics and the questions were discussed and completed telephonically. The conclusion is that the treatment programme of SANCA Witbank is in line with the rest of the drug dependent field and only minimal recommendations were made. / Social Work / MA(SS)(MENTAL HEALTH)

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