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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.
451

Color removal from softwood, kraft, caustic extract effluent by polyamines

Kisla, T. C. (Thomas Carl) 01 January 1976 (has links)
No description available.
452

In-situ biodegradation study using ³⁶Cl labeled bleaching filtrates / In-situ biodegradation study using 36Cl labeled bleaching filtrates

Williams, Chris L. 12 1900 (has links)
No description available.
453

Improving access to drinking water in the developing world through guided household water treatment and storage technology selection

Newton, Jessica 08 July 2011 (has links)
Beginning at least as early as 1977, the international community formally recognized that drinking water and sanitation were not a reality for large percentage of the world and that it was necessary to take action to change this. Over the following three decades more actions and agreements were made, each with a progressively acute awareness of the requirements to achieve this goal and the failures of previous attempts. Poor information sharing and underestimation of cost were identified as two of the greatest recurring impediments. The Millennium Declaration made in 2000 is the newest campaign to move towards this goal, among others, and provides a metric against which progress and success can be measured. At this point, great success has been made overall towards the Millennium Development Goals. Millions of people have gained access to improved sources of drinking water and several regions have surpassed their goals. Unfortunately this progress is not homogenous and the definitions of success are misleading. Sub-Saharan Africa is lagging significantly behind due to water scarcity, large population growth, urban versus rural disparities, and slow growth of piped infrastructure. Limitations to the sector as a whole have been identified as logistics, funding limitations, inadequate cost recovery, and inadequate operations and maintenance. Additionally, the metric of access to an "improved" source does not equate to safe drinking water and is not attached to sanitation improvements or overall health improvements. In further examining the financial aspects of achieving the goals, it is clear that there is a great deal of inconsistency. Many donors, whether public or private, international or local, are giving money to the development goals. But the money given is often not equivalent to the original commitment, not given to the countries with the greatest need, not given to the water and sanitation sector specifically, given in the form of loans which must be repaid, given to new large scale systems which are not always appropriate, or not sufficient to achieve the desired target. This makes it very difficult to achieve and sustain progress in the areas which have been difficult to reach thus far, including Sub-Saharan Africa. The need for progress toward safe water is clear from the perspective of health. Water is needed for hygienic practices, as well as consumption, and it is counterproductive to use water that is not clean. One of the leading causes of both death and disability worldwide is diarrheal disease which can largely be attributed to unsafe water. Studies have shown that there is a positive correlation between drinking water interventions and improved health outcomes, especially with increased proximity of the source, and for this reason there is an even greater need to tie the definition of success in improved water to overall health outcomes. It is also important that public health practitioners, engineers, and professionals from other related sectors work together to improve knowledge sharing and ultimately efficiency in achieving the goal of safe water for all. Point-of-use interventions are among the best approaches to delivering means of water treatment to unreached communities because they can be deployed much more quickly and easily than a traditional piped system, require less expertise, and reduce recontamination that may occur during transport and storage. Such technologies utilize a variety of mechanisms to address a range of contaminants and concerns. In order for any technology to be successful though, it must be accompanied by a method of safe storage as well as education, training, and continued external support. This information is synthesized in a technology selection guide, which attempts provide assistance in technology selection by addressing the immediate issue of water quality for the sake of health benefits, while also considering the context of the installation, the user preferences, the level of expertise of the implementers, the cost, operations and maintenance requirements, and common areas of failure. Simultaneously it allows for technologies to be compared so that the most appropriate technology may be chosen. The guide is marketed towards a non-technical audience with the intention of promoting knowledge sharing and serving as a translation between the developers of the treatment technology and those who implement it in developing countries.
454

Performance evaluation of nanofiltration membranes : theory and experiment

Agboola, Oluranti January 2014 (has links)
D. Tech. Chemical Engineering / Concerns for the limitations of conventional technology for acid mine water treatment and the potential use of waste water have led to increased interest in membrane technologies. Studying the physical properties of nanofiltration membranes is a very important development in nanofiltration separation process. For optimum separation performance, the nanofiltration membranes have to possess certain physical properties, given the appropriate interactions with solutes in the process stream. This study investigated the performance evaluation of Nano-Pro-3012 and NF90 membranes in the treatment of synthetic wastewater effluents and acid mine water and the influence of membrane characteristics on retention in nanofiltration. The research was aimed to evaluate the performance of a new acid stable nanofiltration material (Nano-Pro-3012) produced by Bio Pure Technology for the removal of heavy metals from shaft 8 at Rand Uranium wastewater treatment plant and compare with a commercially available nanofiltration membrane.
455

Removal of emerging contaminants from aqueous solution using carbon nanotube with tailored properties.

Mphahlele, Keletso. January 2013 (has links)
M. Tech. Department of Chemical, Metallurgical and Materials Engineering. / Aimes to explore the effect of using N-CNTs in comparison with undoped CNTs as an anchor for silver or metallic nanoparticles. The metal/CNT will be polymerized with beta-cyclodextrin and will be used as adsorbent for water purification.
456

Experimental investigation and modelling of oligodynamic nanoparticles based filtration system for water disinfection.

Mthombeni, Nomcebo Happiness. January 2011 (has links)
M. Tech. Engineering Chemical. / Developes and evaluate next generation antimicrobial filtration systems based on oligodynamic nanoparticles for complimentary water disinfection systems (CDWS) in under developed regions
457

Bio compatible nano-structured hydrotalcite for the removal of heavy metals from wastewater.

Setshedi, Katlego. January 2011 (has links)
M. Tech. Chemical Engineering. / In this study, nano-structure hydrotalcite material was used as an adsorbent for the removal of heavy metals of lead (Pb), nickel (Ni), cadmium (Cd) and cobalt (Co) from wastewater. It was observed that, in comparison with single component system (Ni, Cd and Co only), the presence of co-ions reduced the Ni (II), Cd (II) and Co (II) adsorption suggesting suppression of the desired ion by the presence of co-existing ions. The kinetic data fitted well to pseudo-second order model while the equilibrium data were satisfactorily described by Langmuir isotherm. The adsorption capacities of Ni (II), Cd (II) and Co (II) at pH 6.0 were found to be 142.8, 200 and 142.8 mg/g at 25oC.
458

The use of maize tassel as a solid phase extraction sorbent for the recovery of copper, gold and silver from aqueous solution.

Sekhula, Mahlatse Mapula. January 2011 (has links)
M. Tech. Environmental Management / Investigates the possibility of using maize tassel powder as a solid phase extraction sorbent for the recovery of Ag, Au and Cu from aqueous solution. The surface characteristics of maize tassel and its ability to remove Ag, Au and Cu from aqueous solutions needed to be established before the preparation of maize tassel beads.
459

Optimisation and validation of methods used to detect amoebae resistant bacteria in water distribution systems.

Muchesa, Petros. January 2011 (has links)
M. Tech. Water care / Free-living amoebae are important predators that feed on bacteria, fungi and algae by phagocytosis. However, a number of bacteria have become resistant to, and are able to survive, grow and exit Free-living amoebae. Free-living amoebae are ubiquitous organisms that have been isolated from various man-made and environmental water systems. Some of these free-living amoebae host amoeba-resistant bacteria such as Legionella spp. Vibrio cholerae and Mycobacterium species which are regarded as human pathogens. The objective of this study was to establish amoebal enrichment and co-culture techniques in order to isolate and identify amoebae and amoeba-resistant bacteria from seeded and environmental water samples. The aim of the study was to introduce and establish amoebal co-culture and amoebal enrichment techniques in South Africa, to provides South African laboratories with baseline information on the efficiency of culture-based methods as well as analytical requirements like incubation temperature, media preparation and storage conditions for amoebal enrichment and co-culture techniques for the detection and isolation of amoebae and amoeba-resistant bacteria from environmental water systems.
460

Anaerobic treatment of benzoate- and phenol- containing wastewaters

Chen, Tong, 陳彤 January 1996 (has links)
published_or_final_version / Civil and Structural Engineering / Master / Master of Philosophy

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