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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

The Situation Of Ecodesign In Turkish Industry

Gurakar, Ece 01 October 2008 (has links) (PDF)
Ecodesign is an approach for product development, which focuses on minimizing the environmental impacts of the product during the whole life cycle while maintaining the major concerns such as function, usability, aesthetic and ergonomic qualities. This approach is regarded as a fundamental step to achieve sustainable production, consumption and development. The thesis examines the current situation of ecodesign in Turkish Industry, in relation to design and manufacturing. First, it introduces the literature on ecodesign in general, and more specifically, it presents a comparative analysis of six international studies with an aim to explore internal and external stimuli for promoting ecodesign, as well as reflections on barriers that were encountered. Then, literature review on ecodesign activities in Turkish industry is discussed. To complement these findings, the results of the interviews conducted with three stakeholder groups (i.e. government, universities and industry) are presented. Finally, the results of a study that was conducted in Turkish packaging, and electric &amp / electronics sectors to understand approaches of environmentally-conscious product development, the drivers and the barriers of ecodesign implementation into these sectors are revealed. The level of ecodesign implementation is found to be strongly related with the economic situation of Turkish context, which is the most important determining factor for the drivers and barriers found in the study. Acquiring a more stable economic situation, ecodesign will become a considerable competitive advantage through: (i) reduction of manufacturing costs in the long term, (ii) innovational approach in the manufacturing process and product development, and (iii) increasing brand awareness.
22

Occurrence, Distribution And Sources Of Polychlorinated Biphenyls At Selected Industrial Sites In Turkey

Gedik, Kadir 01 June 2010 (has links) (PDF)
In this study, the occurrence and distribution of polychlorinated biphenyls (PCBs) were investigated via sampling studies conducted around a thermal power plant (Seyit&ouml / mer, K&uuml / tahya), a scrap metal yard (Kizilirmak, Kirikkale), transformer repair and maintenance facility (Lake Eymir, Ankara), and two organized industrial districts (izmit and Mersin), and 120 samples composed mainly of sediments were collected from those sites. Total PCBs ranged from not detected to 385 ng/g for all samples. Analysis of samples indicates enrichment of PCBs with special emphasis to sediments collected around the Seyit&ouml / mer thermal power plant. Congener specific results indicate domination of profiles by penta- and hexa-chlorobiphenyls. Overall, the PCB concentrations observed in sampling sites are comparable to the background levels of soil/sediments around the world. To identify relevant pollution sources, congener specific data were further evaluated in the subsequent process of source apportionment using Chemical Mass Balance (CMB) receptor model. A general overview of the source apportionment results indicate that equipments (transformers and capacitors) mainly used in the energy generation/transmission and high energy consuming industries as the major PCB sources. PCBs used in open applications were also predicted as sources depending on site characteristics. Overall, indications of contaminated sites are evident in a number of locations / yet, no major contamination is evident in any media according to the current relevant national regulatory actions. However, findings of this study suggest that, over expanded time exposure, threat to the environment and human health may be of concern.
23

Model for End of Life Treatment of Polymer Composite Materials

Hedlund-Åström, Anna January 2005 (has links)
<p>Because of increasing environmental demands, especially on dealing with products end of life phase, product manufacturers and designers must consider the future disposal of their products. For conventional materials like steel and aluminium well-functioning recycling methods exists. This is not the case for structures of polymer composites, which are used more extensively, especially for structures like vehicles and vessels. Several techniques do exist but they are not yet commercially available. The current disposal methods of polymer composites are landfill and incineration.</p><p>Polymer composites are materials, which consist of several materials like fibre, matrix, and additives. In the form of sandwich constructions also foam core material is added. This circumstance complicates the waste treatment of composite materials. In this thesis a model for assessing possible future waste treatment techniques for polymer composites including sandwich structures is presented. The model is meant to be used as an aid for preparing future disposal for end of life products for planning waste treatment and for facilitating communication in contacts with waste receivers.</p><p>Recommendations for waste treatment have been formed for a number of polymer composites. These recommendations are based on the analysis of costs and environmental effects and they compare different scenarios for mechanical material recycling and energy recovery by waste incineration. The result of this study points out material recycling as the preferable method for the main part of the studied materials. But this recommendation is strongly dependent on type of virgin material replaced by the recycled material. Energy recovery can also be considered if the polymer composite waste replaces coal, which is non renewable. Though incineration will always result in a cost for the waste producer.</p><p>In the recommendations mentioned above no information concerning implementation of the different waste disposal techniques is included. Therefore, in this study a model for assessing possible waste disposal techniques for polymer composites is presented. The model is based on internal factors, which are related to the waste and to the processes. To implement the model relevant waste properties must be identified in order to fulfil the conditions set by the required processes involved.</p><p>A case study was carried out using the proposed model for assessing different waste disposal techniques for the hull of the Visby Class Corvette in the Royal Swedish Navy. Six different techniques were studied for the hull structure. Since almost all the important waste properties were known and the waste was assessed to be treatable all the included techniques except one are shown to be usable in the future.</p><p>Many investigations have pointed out material recycling as the best alternative considering environmental effects. This is also valid for polymer composite materials. Since recycling polymer composites is a complicated process, especially recycling thermoset composite it is important to aquire comprehensive information about the constituents of these materials.</p>
24

Resilient landscapes : socio-environmental dynamics in the Shashi-Limpopo Basin, southern Zimbabwe c. AD 800 to the present /

Manyanga, Munyaradzi, January 1900 (has links)
Diss. Uppsala : Uppsala universitet, 2006.
25

The Development of a Human Polyomavirus Quantitative PCR Assay to Assess Viral Persistence, Water Quality, and Human Health Risks

McQuaig, Shannon M. 06 November 2009 (has links)
Microbial water quality is generally assessed using fecal indictor organisms; however host-specific microbial source tracking (MST) methodologies can be employed to differentiate sources of fecal pollution. The central goal of this research was to develop and validate a QPCR assay for the quantification of two human-specific polyomaviruses (HPyVs) in environmental water samples. These viruses are prevalent worldwide and produce lifelong, asymptomatic viruria in immunocompetent individuals. A Taqman® quantitative PCR (QPCR) assay based on the conserved T-antigen of two HPyVs (JCV and BKV) was developed and optimized (Chapter 2). HPyVs were detected in a high proportion of human-associated waste samples (e.g. sewage) and were not detected in animal excrement samples (Chapter 2). The effects of ultraviolet radiation, temperature, and salinity on the persistence of HPyVs in water were reported in Chapter 3. Laboratory studies analyzing the effects of various UV doses, temperatures, and/or salinities demonstrated high doses of UV were required to significantly decrease the detection of HPyVs DNA and salinity stabilized pure cultures of HPyVs virus particles at high temperatures (25°C and 35°C). Solar radiation as well as potential predation from microorganisms in sewage significantly reduced the persistence of HPyVs DNA in outdoor mesocosm studies (Chapter 3). An improved method to extract human polyomavirus (HPyVs) DNA from environmental water samples was developed, and the recoveries were larger and more consistent over a range of DNA concentrations as compared to the standard protocol (Chapter 4). In the California beaches study (Chapter 4), the presence of HPyVs by either QPCR or PCR had a high degree of matching results with the adenoviruses (83-91%), Methanobrevibacter smithii marker (82-92%) and moderate degree of matching results with the human-associated Bacteroidales spp. marker (57-80%) (Chapter 4). HPyVs were detected in the presence of various pathogens including: Giardia spp., Cryptosporidium spp., Vibrio spp., enteroviruses, and noroviruses (Chapter 5). The presence of HPyVs in relatively high concentrations of sewage and the specificity of HPyVs combined with the relatively conservative persistence of HPyVs when exposed to environmental conditions and the correlation of HPyVs with pathogens demonstrates that this assay is a useful MST method to detect human sewage.
26

Assuandammens påverkan på Nilen, Egypten

Lehman, Hanna January 2013 (has links)
Regulation of rivers by dams and reservoirs is a good example where anthropogenic impact could be considerable both in the local environment, but also has major implications upstream and downstream. This study was accomplished as a literature study of the river Nile, which is extremely important for water supply. The purpose of this study was to investigate the consequences of the construction of the Aswan High Dam, to obtain a consistent flow for water supply, irrigation and power generation in Egypt. Since Egypt has a very hot and dry climate large amounts of water in reservoir is lost to the Nubian aquifer system and by evaporation. The consequences from constructing the dam are considerable. It has led to the preventing of the annual flooding and a significant reduction in sediment load reaching the outer delta, which has led to an erosion of the delta front. The incoming waves create a current, mainly towards the east, carrying away the eroded material. In order to protect the delta front seawalls and breakwaters has been built. They have stopped the erosion of the areas behind them, but it has also led to the erosion of other areas. The issues in Egypt reflect the global crisis, mainly in delta areas, which prevail in regulated rivers. The biggest issue globally is the reduced sediment transport to the coast that causes land loss.
27

Light and other environmental effects on nutritional quality of lettuce / Šviesos ir kitų aplinkos veiksnių poveikis salotų maistinei kokybei

Sirtautas, Ramūnas 26 September 2014 (has links)
The aim of the research was to investigate the solid-state lighting parameters with natural lighting sources in horticulture effect on nutritional quality of baby leaf lettuce. The tasks of the research: 1. To investigate the effects of solid-state lighting on different leaf lettuce varieties nutritional quality in phytotron chambers. 2. To evaluate the impact on combination of blue and green light-emitting diodes with high-pressure sodium lamps lighting, at the stage of technological maturity, on the different varieties of lettuce internal quality in different growing seasons in greenhouses. 3. To evaluate the effect of supplemental 638-LED lighting, supplemental with natural and high pressure sodium lamps in greenhouse on the nutritional quality of lettuce in different growing seasons. 4. To investigate the effect of supplemental 638-LED lighting on the nutritional quality of lettuce lasting effect. / Tyrimų tikslas. Ištirti kietakūnio apšvietimo parametrų ir jo derinių su įprastiniais daržininkystėje šviesos šaltiniais efektus salotų maistinės kokybės valdymui. Tyrimų uždaviniai: 1. Fitotrono kamerose ištirti kietakūnio apšvietimo spektro efektus skirtingų veislių lapinių salotų maistinei kokybei 2. Gamybiniuose šiltnamiuose įvertinti kombinuoto mėlynų, žalių šviesos diodų su aukšto slėgio natrio lempomis apšvietimo, taikomo technologinės brandos tarpsnyje, poveikį skirtingų veislių salotų vidinei kokybei skirtingais auginimo sezonais. 3. Įvertinti trumpalaikį didelio srauto tankio raudonos LED (638 nm) šviesos, papildomos natūraliam ir aukšto slėgio natrio lempų apšvietimui šiltnamyje, poveikį salotų maistinei kokybei skirtingais auginimo sezonais. 4. Ištirti trumpalaikio papildomo raudonų 638 nm LED apšvietimo poveikio salotų maistinei kokybei išliekamąjį efektą.
28

Avaliacao da toxicidade de aguas de chuva a organismos aquaticos / Evaluation of toxicity of rainwater on aquatic organisms

MARTINS, RENATA de S.L. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:27:07Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:20Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
29

Sobre a influencia de fatores ambientais nos niveis de radonio em cavernas dos Parques Estaduais do Vale do Ribeira, SP e avaliacao do equilibrio radioativo e fator de equilibrio entre radonio e seus descendentes / On the influence of environmental factors on radon levels in caves of Ribeira Valley State Parks, SP and evaluation of radioactive equilibrium and equilibrium factor between radon and its progeny

ALBERIGI, SIMONE 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:12Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:13Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
30

Aspectos ambientais do processo de fabricacao de placas de revestimentos ceramicos ( via umida ) , com enfase nos efluentes liquidos

FERRARI, KATIA R. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:24Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:21Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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