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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.
81

Tailored glycopolymers

Ramiah, Vernon 12 1900 (has links)
Thesis (PhD (Chemistry and Polymer Science))--Stellenbosch University, 2008. / The synthesis of glycopolymers with various comonomers as prepared via the RAFT process is investigated. The macro-RAFT agent poly(3-O-methacryloyl-1,2:5,6-di-O-isopropylidene-D-glucofuranose) (PMAlpGlc) was prepared by polymerization of the glycomonomer with cumyl phenyl dithioacetate as the chain transfer agent. Chain extension with styrene or methyl acrylate or acrylic acid afforded novel diblock copolymers, (PMAlGlc-b-poly[styrene] or PMAGlc-b-poly[methyl acrylate] or PMAlGlc-b-poly[acrylic acid]), with predetermined molecular weights and narrow molecular weight distributions. The poly(acrylic acid) based glycopolymer was used to modify the surface of CaCO3, forming what will be referred to as a ‘sugar-coated CaCO3’ particle. This surface modifying effect was evaluated in depth; a schematic study of the effect of reaction temperature, pH, reaction time and glycopolymer concentration on CaCO3 crystallization was carried out. The analytical techniques Thermal Gravimetric Analysis (TGA) and Scanning Electron Microscopy (SEM) were used to verify that these ‘sugar-coated CaCO3’ particles have an increased adherence to cellulose compared to ‘non sugar-coated’ particles. A series of polymer configurations comprising various ratios of glycomoiety to poly(acrylic acid) was prepared. The effect of this polymer series on CaCO3 crystallization was evaluated and the ideal polymer configuration and its optimum synthesis conditions (i.e. reaction pH, temperature, time and polymer concentration) that gave maximum adherence of the ‘sugar-coated CaCO3’ particle onto cellulose were identified. The ability of these poly(acrylic acid) based glycopolymers to increase the interaction between CaCO3 and cellulose was then evaluated. This was done by simply mixing all three substrates, i.e. glycopolymer, cellulose and CaCO3 together. Analysis by TGA, SEM and Thin Layer Chromatography (TLC) revealed both the ideal polymer configuration that favoured increased adherence of the CaCO3 to cellulose and the optimum reaction conditions required for application and testing. In addition to studying the interaction between cellulose and CaCO3, the amphiphilic nature of the glycopolymers was determined. Transmission Electron Microscopy (TEM) confirmed that coreshell particles were prepared and that these particles are solvent exchangeable (in the case of styrene and methyl acrylate glyco-blocks) or pH exchangeable (in the case of acrylic acid glyco-blocks).
82

Case study of how a project is proposed for possible inclusion in China's seventh five-year plan, 1986-1990

楊潤財, Yeung, Yun-choi. January 1986 (has links)
published_or_final_version / Business Administration / Master / Master of Business Administration
83

Water usage in the South African pulp and paper industry.

Macdonald, C. J. M. January 2004 (has links)
The pulp and paper industry holds a reputation in the public eye for being a large consumer of water. This dissertation analyses water usage within the industry with a particular application to the South African pulp and paper industry. Unlike in other paper-producing countries, water in South Africa is a scarce commodity with a wide range of consumers. Faced with this, it is important for the leaders of the paper industry to have a tool with which to manage water consumption. This dissertation analyses the water usage aspects (including volumes needed and water quality needed) of the different processes, as well as the impact of different products, describing the reasons for water usage in each process. The application of best available technologies for water reduction is discussed. A theoretical or expected range and norm for water usage for each of seventeen South African mills is derived, based on each mill's particular processes, capacities and products. The actual water usage by each mill was surveyed by personally interviewing personnel at each mill. Comparisons are made between expected and actual water usage, and the total daily water consumption of the industry is derived. Only two mills operate below the expected norm level, most smaller mills operate close to the norm level, while five of the larger mills need to apply various techniques to reduce their water usage. The approximation of mill water usage to the predicted or expected norm clearly supports the hypothesis that water usage can be predicted by analysing process and capacity, and indicates that this dissertation can be used as a tool to manage water usage within the industry. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2004.
84

Water usage in the South African pulp and paper industry.

Macdonald, C. J. M. January 2004 (has links)
The pulp and paper industry holds a reputation in the public eye for being a large consumer of water. This dissertation analyses water usage within the industry with a particular application to the South African pulp and paper industry. Unlike in other paper-producing countries, water in South Africa is a scarce commodity with a wide range of consumers. Faced with this, it is important for the leaders of the paper industry to have a tool with which to manage water consumption. This dissertation analyses the water usage aspects (including volumes needed and water quality needed) of the different processes, as well as the impact of different products, describing the reasons for water usage in each process. The application of best available technologies for water reduction is discussed. A theoretical or expected range and norm for water usage for each of seventeen South African mills is derived, based on each mill's particular processes, capacities and products. The actual water usage by each mill was surveyed by personally interviewing personnel at each mill. Comparisons are made between expected and actual water usage, and the total daily water consumption of the industry is derived. Only two mills operate below the expected norm level, most smaller mills operate close to the norm level, while five of the larger mills need to apply various techniques to reduce their water usage. The approximation of mill water usage to the predicted or expected norm clearly supports the hypothesis that water usage can be predicted by analysing process and capacity, and indicates that this dissertation can be used as a tool to manage water usage within the industry. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2004.
85

Water usage in the South African pulp and paper industry.

Macdonald, C. J. M. January 2004 (has links)
The pulp and paper industry holds a reputation in the public eye for being a large consumer of water. This dissertation analyses water usage within the industry with a particular application to the South African pulp and paper industry. Unlike in other paper-producing countries, water in South Africa is a scarce commodity with a wide range of consumers. Faced with this, it is important for the leaders of the paper industry to have a tool with which to manage water consumption. This dissertation analyses the water usage aspects (including volumes needed and water quality needed) of the different processes, as well as the impact of different products, describing the reasons for water usage in each process. The application of best available technologies for water reduction is discussed. A theoretical or expected range and norm for water usage for each of seventeen South African mills is derived, based on each mill's particular processes, capacities and products. The actual water usage by each mill was surveyed by personally interviewing personnel at each mill. Comparisons are made between expected and actual water usage, and the total daily water consumption of the industry is derived. Only two mills operate below the expected norm level, most smaller mills operate close to the norm level, while five of the larger mills need to apply various techniques to reduce their water usage. The approximation of mill water usage to the predicted or expected norm clearly supports the hypothesis that water usage can be predicted by analysing process and capacity, and indicates that this dissertation can be used as a tool to manage water usage within the industry. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2004.
86

Application of pinch technology in an integrated pulp and paper mill.

Naylor, Gladys M. January 2003 (has links)
The objective of this investigation was to utilise water pinch analysis as a tool for the optimisation of fresh water use in an integrated pulp and paper mill. The investigation was carried out at Mondi Paper in Merebank, south of Durban. The pulp and paper manufacturing process is a large consumer of fresh water and minimising the amount of fresh water used in the processes is beneficial from both a cost and environmental point of view. There are examples of mills which have "closed" their water systems to the extent that fresh water make up is minimal and most of the water is recycled and reused in a closed loop. These examples provide guidance on the basis of proven methods for reducing water consumption in the pulp and paper industry and can be used as a reference for mills wishing to reduce water consumption by making use of tried and tested methods. This investigation sought to provide an alternative method to identifying potential savings in fresh water consumption by making use of water pinch analysis. This was done at Mondi Paper by analysing individual parts of the mill and then a larger section of the mill which included both pulp and paper production. Flow rates of water streams and fibre content in those streams were obtained from plant data, where available, and this data was used to produce.a mass balance using the Linnhoff-March software, Water Tracker. The balance produced using Water Tracker provided the missing flow and fibre content data and this data was used as the input for the Linnhoff-March software, Water Pinch , to perform the water pinch analysis. The results achieved when analysing the individual parts of the mill did not demonstrate potential for significant savings in fresh water consumption, however the analysis of the integrated section of the mill identified a potential reduction in fresh water. It was found that the application of a single contaminant analysis to the larger section of the mill identified a possible reduction in the freshwater requirement of 8.1% and a reduction in effluent generated of 5.4%. This is a savings of R1 548 593 per annum based on 2003 costs of fresh water and effluent disposal. This analysis was conducted using the most simplified representation possible to produce meaningful results in order to evaluate the effectiveness of water pinch analysis in optimising the fresh water consumption in an integrated pulp and paper mill. It is demonstrated that water pinch analysis is potentially a useful tool in determining the minimum fresh water requirement of a site. / Thesis (M.Sc.Eng.)-University of Natal, Durban, 2003.
87

Materials and new designs in sustainable community development : a case study of Phumani Paper's Eshowe and Endlovini projects

14 January 2014 (has links)
M.Tech. (Fine Art) / As a Fine Art graduate student, I worked at Phumani Paper Project's research unit based at the Technikon Witwatersrand from 2001 to 2004. The experience allowed me to render my services as a trainer for craft product design to help develop and sustain the poverty alleviation programme for Phumani Paper's papermaking projects around the country. Participants of the project benefit from the program in terms of training in the making of craft items, personal capacity building, and income generating opportunities. South Africa's history is fundamental to understanding the present social imbalance which the government, non-governmental organisations and private organisations are trying to address in various ways. My research work at the KwaZulu-Natal Papermaking and Packaging Project (KZN-PCPP) in Eshowe culminated in the writing of this dissertation. My research explored issues related to materials and design for the sustainability of the KZNPCPP. In regard to poverty alleviation I used Participatory Action Research (PAR), which was core to the activities and works presented in this dissertation. New designs for the packaging of craft products introduced during my intervention period helped improve the marketability of the products produced at KZNPCPP, and helped the participants to learn new skills. I focused on the introduction of sugar cane paper pulp in the making of ceramic wares. This added value to the potters' experience and to a certain extent helped reduce losses due to breakage during transportation.
88

The determination of core competencies of Sappi Forest Product Division as a basis of establishing future development

Khan, Imtiaz January 2004 (has links)
Thesis (M.B.A.)-Business Studies Unit, Durban Institute of Technology, 2004 iii, 111 leaves / The purpose of this study was to determine the core competencies of Sappi Forest Product division as a basis for establishing future developments. The literature focused on the resource-based view where the analysis of the firm’s internal resources and capabilities can be used as the starting point of strategy. / M
89

The importance of end customer value in the paper industry

Herlitz, Erik January 2019 (has links)
In a more digitalized world the paper industry has struggled to deliver customer value and stay relevant when the digital media has started to emerge. This problem has especially happened to newspaper which has seen a decline in Sweden with over 20% the last decade. Paper mills has also started to destroy shareholder value as many mills only work with offering customers low prices and tries to outlive their competitors. This has led to the following research objective of this study:  To examine the importance of end customer value in paper industry for developing market shares in the digital era. This study has been an exploratory and descriptive study with a qualitative data collection. The data has been to one part been collected through a market survey that has asked end-users how they perceive price and quality when comparing two different types of paper. Also interviews with one paper producer and two printing companies have been done to cover the professional aspect of customer value for the paper industry.  It has been clearly shown in this study that customers and companies inside the paper industry are agreeing in which customer values being most important, quality and price. The importance of being innovative was also stated by interviewed printing companies and the paper producer. The market survey was a good example of how innovation, from a paper producer, related to important customer values – perceived quality and perceived price – can create a potentially higher market share and profitability, instead of just lowering their prices and try to outlive their competitors.  The study has also contributed to see that companies inside the paper industry are conscious that they face tough competition from a more digitalized world. Even though the companies know that they face competition from the digital media the companies have a good understanding of which products they can continue to compete with and which products that digital media has the upper hand on.
90

La importación de papel y el efecto de las políticas de desarrollo sostenible aplicados en el Perú / The importation of paper and the effect of sustainable development policies applied in Peru

Cárdenas De la Cruz, Christian Edgardo, Salazar Manuyama, Fiorella Marcia 04 July 2019 (has links)
La presente investigación tiene como finalidad estudiar si los efectos de la importación de papel y cartón en el Perú puede estar influenciada por la promoción de políticas de desarrollo sostenible en el mismo sentido que se aplican en Colombia, en particular con respecto a las medidas de protección al medio ambiente, tales como la reducción del uso, la reutilización y el reciclaje. La investigación contiene cinco puntos, el primer capítulo presenta el marco teórico que explica acerca del desarrollo sostenible, cuáles son los modelos aplicados en Colombia y Perú, los inicios de la industria en Perú, procesos de producción e importación, la tecnología y su impacto en la industria peruana, comportamiento de la industria de papel a nivel internacional, avances que ha tenido el Perú en temas medioambientes, políticas eco amigables aplicadas en los últimos cinco años y certificaciones manejadas dentro del sector. En el segundo capítulo se plantea la metodología de investigación, donde se exponen el problema de investigación, los objetivos, las hipótesis, el diseño metodológico, los actores a entrevistar y las variables planteadas para la elaboración de nuestra investigación. En el tercer capítulo, se muestra la información recabada de las entrevistas realizadas a los actores. En el cuarto capítulo, se realiza un análisis de los hallazgos encontrados luego de procesar la información. Además, se explican las dificultades de la investigación y brecha de la información presentada en el estudio. Finalmente, en el quinto capítulo se presenta las conclusiones y recomendaciones de la investigación. / The purpose of this research is to study whether the effects of the import of paper and cardboard in Peru may be influenced by the promotion of sustainable development policies in the same sense as those applied in Colombia, in particular with regard to protection measures to the environment, such as reducing use, reuse and recycling. The research contains five points, the first chapter presents the theoretical framework that explains about sustainable development, what are the models applied in Colombia and Peru, the beginnings of the industry in Peru, production and import processes, technology and its impact on Peruvian industry, behavior of the paper industry at international level, advances that Peru has had in environmental issues, eco-friendly policies applied in the last five years and certifications managed within the sector. In the second chapter the research methodology is presented, where the research problem, the objectives, the hypotheses, the methodological design, the actors to be interviewed and the variables proposed for the elaboration of our research are exposed. In the third chapter, the information collected from the interviews with the actors is shown. In the fourth chapter, an analysis of the findings found after processing the information is performed. In addition, the difficulties of the investigation and the information gap presented in the study are explained. Finally, the conclusions and recommendations of the research are presented in the fifth chapter. / Tesis

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