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Aflatuni, Abbas. "The yield and essential oil content of mint (Mentha ssp.) in northern Ostrobothnia /." Oulu : Oulun Yliopisto, 2005. http://herkules.oulu.fi/isbn9514277465/.
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Landsburg, Craig. "Quality evaluation of essential oil from Nova Scotia grown mint." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0021/MQ57302.pdf.
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Aflatuni, A. (Abbas). "The yield and essential oil content of mint (Mentha ssp.) in Northern Ostrobothnia." Doctoral thesis, University of Oulu, 2005. http://urn.fi/urn:isbn:9514277465.
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Abstract
Peppermint (Mentha x piperita L.) oil is one of the most popular and widely used essential oils, mostly because of its main components menthol and menthone. Peppermint oil is used for flavouring pharmaceuticals and oral preparations. Corn mint is the richest source of natural menthol. Carvone-scented mint plants, such as spearmint (M. spicata), are rich in carvone and are widely used as spices, and they are cultivated in several countries. Studies were made into the yield and essential oil content of several mint species and the original. The general aim of the work was to examine the optimal conditions for cultivating mint in Northern Finland. The specific aims of the study were (first) to investigate the differences in the oil content for several mint species and (secondly) to compare the effect of various factors such as plant spacing (10, 20 and 30 × 50 cm), liming (0, 4, 8, 12 and 16 tons ha-1), propagation methods (micropropagated and conventionally propagated plants) and harvest date (once at the end of August in comparison with first cut at the beginning of August and second cut in mid September) on the cultivation success, quality and quantity of the plants. The constituents of the essential oil were analysed from leaf samples using GC-MS.
Among the peppermints of different origins studied, peppermint of USA and Egypt origin ('Black Mitcham') contain the highest menthol and optimum oil yield. Corn mint and Sachalin mints both had high menthol content. Due to several reasons, such as no significant differences between the different densities and oil composition, markedly higher amount of weeds at 30 × 50 cm than at 10 × 50 and 20 × 50 cm spacing and the high seedling costs and the danger of fungi and disease at a 10 × 50 cm spacing, a plant optimum of 20 × 50 cm spacing is recommended for Northern Ostrobothnia. If the pH value is lower than 6, or levels of Mg and Ca are low, liming at a rate of 4–8 t ha-1 for sandy soils in Finland is recommended in order to achieve higher fresh and oil yields. In the first year, there were no differences in the dry leaf yield of micropropagated and conventionally propagated plants, but the menthol content was significantly higher in conventionally than in micropropagated plants. In the second year, only the dry leaf yield of micropropagated plants was higher than that of their conventionally propagated counterparts. Cutting peppermint only once during full bloom (the end of August) gives the maximum oil yield of good quality. In conclusion, it is possible to achieve as high as or even higher oil quality and dry yield in North Ostrobothnia than it is in central Europe or south Asia. However, this requires observing certain cultivation factors such as having the right type of mint, soil pH, planting density, harvesting time and propagation method In addition, mints must be cultivated in the same place for only two and a maximum for three years.
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HEJNA, MONIKA. "PLANT-BASED STRATEGIES TO CONTROL THE ZINC AND THE COPPER OUTPUT FROM SWINE LIVESTOCK." Doctoral thesis, Università degli Studi di Milano, 2021. http://hdl.handle.net/2434/821594.
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The current state of agriculture, where demand for safe food is increasing rapidly as a consequence of growing population, raises a number of questions related to the one health approach and sustainable animal production with minimal impact on the environment. Swine production is an important branch of food production where weaning is the most vulnerable phase for piglets, often associated with decrease of growth performance and diarrhoea. The maintenance of gut health is therefore a complex endeavour where nutrition is crucial in order to reduce the intestinal disorders. Antimicrobial resistance is also a significant global concern. Reducing antibiotic use in animal production systems decreased prevalence of antibiotic-resistant bacteria in animals about 15%. In the last decade, the European Union banned the antibiotic use as growth promoters in livestock (EU Reg. 1831/2003). The first antibiotic alternative was the wide application of essential nutrients such as zinc (Zn) and copper (Cu) salts in the form of premix in the diets of animals to control digestive disorders. Due to their low bioavailability, Zn and Cu are commonly found in animal’ manure as a reflection of their content in the feed. The use of Zn and Cu in feed may also have contributed to the emergence of methicillin-resistant Staphylococcus aureus (MRSA). Despite antibacterial and anti-inflammatory activities, the first adopted alternative against in-feed antibiotics became unsafe due to heavy metal’ pollution in livestock wastewater. In order to reduce the high concentration of Zn and Cu and the antibiotic use in animal diets, plant extracts and different phytochemicals are of potential interest due to their antimicrobial, antioxidant and anti-inflammatory properties. However, if nutritional ecology’ strategy is not sufficient to reduce the wastewater pollution of heavy metals from livestock production, the development of efficient methods such as multidisciplinary phytoremediation approach is required. First, the preliminary aim was to overview of the role and the main challenges related to the content of essential heavy metals in
animal feed and to evaluate the concentration of heavy metals from feed and faeces in animal rearing systems in northern Italy. Based on an overview, the main second aim was to develop a plant-based integrated approach to reduce the input and output of both Zn and Cu as well as the use of antibiotic compounds in pig production. Hence, in order to reduce input, the first aim was to test several natural plant-based phytochemicals compounds (tannins and leonardite) in vivo and to test of the anti-inflammatory effects of peppermint oil and spearmint oil with porcine alveolar macrophages in vitro. The last aim was to assess the ability of two aquatic species, Typha latifolia and Thelypteris palustris to control the Zn and Cu output from contaminated livestock wastewaters as a cost-efficient phytoremediation strategy. The in vivo data revealed that natural plant extracts (leonarditre and tannins) improved animal health. High doses of tannins (1.25%) supplementation showed slight reduction of diet digestibility and protein utilization, however this did not influence on feed intake and growth performance of animals. The inclusion of 0.25% leonardite improved the zootechnical performance, serum lipid profile and gut epithelium integrity, indicating a good general health status. In vitro study results showed that both mint oils significantly reduced TNF-α secretion from macrophages. To conclude, leonardite supports an improved stress response in weaned piglets, high dose of tannins did not impair growth performance and both peppermint and spearmint oils had anti-inflammatory activities in vitro. Moreover, results obtained from the phytormediation trial showed that Typha latifolia and Thelypteris palustris can accumulate and translocate Zn and Cu from contaminated wastewater. Thus, phytoremediation was effective to counteract the output of zinc and copper, and possibly other heavy metals from the livestock industry. Hence, an integrated nutritional ecology strategy and phytoremediation approach, in accordance with the modern principles of agroecology is needed to reduce the antibiotics use and heavy metals pollution in food-producing animals. Moreover, plant-based strategy guarantees the improvement of the health status of human and animal and leads to increase of the sustainability in animal rearing systems.
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ALMEIDA, Alany Moisa Bezerra de. "Viabilidade agroeconômica da hortelã (Mentha piperita L.) em dois cultivos sob doses de jitirana e épocas de colheita." Universidade Federal de Campina Grande, 2016. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/806.
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ALANY MOISA BEZERRA DE ALMEIDA -- DISSERTAÇÃO PPGSA PROFISSIONAL 2018..pdf: 841322 bytes, checksum: 839ba5af833854ad276c1cdc955c7341 (MD5)Made available in DSpace on 2018-05-25T13:08:12Z (GMT). No. of bitstreams: 1 ALANY MOISA BEZERRA DE ALMEIDA -- DISSERTAÇÃO PPGSA PROFISSIONAL 2018..pdf: 841322 bytes, checksum: 839ba5af833854ad276c1cdc955c7341 (MD5) Previous issue date: 2016-11-29
A hortelã é uma planta bastante utilizada como planta medicinal e alimentícia, sendo produzida por agricultores em sistema familiar de produção. Dois experimentos foram conduzidos na Fazenda Experimental Rafael Fernandes, no distrito de Alagoinha, zona rural de Mossoró-RN, com o objetivo de avaliar o cultivo orgânico da hortelã sob diferentes doses de jitirana e épocas de colheita. O primeiro experimento foi conduzido no período de 13/08/2015 a 09/12/2015, e o segundo no período de 09/11/2015 a 10/12/2015, no delineamento experimental de blocos completos casualizados com os tratamentos arranjados em esquema fatorial 4 x 3, com três repetições. O primeiro fator foi constituído por quatro doses de jitirana (0,0; 0,5; 1,0 e 1,5 kg m-2 de canteiro em base seca) e o segundo fator, correspondendo a três épocas de colheita (30; 60 e 90 dias após o transplantio). Para a cultura da hortelã utilizou-se a cultivar “Mentha piperita”. As características avaliadas foram as seguintes: altura da biomassa, produção de biomassa, número de molhos, massa seca, teor e rendimento de óleo. Alguns indicadores econômicos foram observados, tais como: custo de produção, renda bruta, renda líquida, taxa de retorno e índice de lucratividade. Houve interação entre os fatores-tratamentos para o primeiro cultivo (produção, número de molhos e teor de óleo) e na rebrota da hortelã, nas características (rendimento e teor de óleo). No primeiro cultivo, houve acréscimo no número de molhos de hortelã em função dos fatorestratamentos com valores máximos de 1300; 3503 e 2651 unidades/100m2 nas épocas 30;60 e 90 dias, correspondendo as doses 1,3; 0,2 e 0,2 kg/m2, respectivamente. Na rebrota apresentou número médio de molhos de 2805 unidades/100 m2 (30 dias) e 2542 unidades/100 m2 (60 dias). A dose de 0 kg m2 de jitirana na época de colheita de 60 dias em primeiro cultivo, proporcionou rentabilidade liquida de R$ 3.458,00, taxa de retorno da ordem de R$ 3,26 e índice de lucratividade de 69,3%. Para a rebrota ocorreu rentabilidade liquida de R$ 2.753,00, taxa de retorno de 2,80 e índice de lucratividade de 64,2% na dose de 0 kg m-2 e época de colheita de 30 dias. A produção de hortelã em sistema orgânico de produção constitui-se em alternativa para o produtor.
The plant consortium presents itself as one of the most appropriate methods to the practice of horticulture, in agroecological molds with numerous advantages in the environmental aspect, productive and economical. Two experiments were conducted at the Experimental Farm Rafael Fernandes in Alagoinha district, a rural area of Mossoró- RN, in order to assess the agricultural economic viability of mint consortium with coriander fertilized with manure jitirana more beef. The first experiment was conducted in the period from 08.11.2015 to 11.05.2015 and the second experiment in the period from 11.27.2015 to 22.03.2016, in a randomized complete block with treatments arranged in a 2x4 factorial design with three replications. The first factor consisted of monocropping and intercropping mint and coriander, and the second factor was the different doses of jitirana mixed with manure (0.0, 1.0, 2.0 and 3.0 kg m- 2 site). For mint culture was used to cultivate "Mentha piperita". For the coriander was used to cultivate "Verdão". The characteristics evaluated for the Mint culture were as follows: height of biomass, fresh weight, number of sauces, dry mass, oil content and yield. For the coriander crop the following characteristics were evaluated: plant height, number of stems plant-1, productivity, number of sauces and dry mass. Also economic indicators were used, such as land equivalent ratio (LER), cost of production, gross income, net income, rate of return and profitability index. The use of more manure jitirana cattle contributed to the increase of the productive characteristics of the consortium in the two growing seasons, with number of mint sauces 17.6 and 5.8 in 3.0 doses and 2.2 kg m-2 respectively. For coriander crop, the values were 16.5 and 15.3 m2 sauces in 3.0 kg dose m-2, respectively. The equivalent area obtained in the two experiments were 1.72 and 1.78, respectively. The greater economic efficiency of the consortium was observed in the first growing season with the application of 3.0 kg m-2 of more manure jitirana cattle in an area of 100 m2, with gross income of R $ 3,761.00; net income of R $ 2,727.50; return rate of R $ 3.64 and 72.52% profitability index.
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Luik, Oliver. "Integration von ODL und OQL mit dem Aktiven Semantischen Netz." [S.l.] : Universität Stuttgart , Fakultät Informatik, 1998. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB6783563.
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Agars, Robert C. "Assessment of the potential environmental effects of soluble hydraulic oil on natural waters /." [Richmond, N.S.W.] : Centre for Electrochemical Research and Analytical Technology, School of Science, Food and Horticulture, University of Western Sydney, 2001. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030409.114931/index.html.
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Thesis (M.Sc. (Hons))--University of Western Sydney, 2001."A thesis presented for the Degree of Master of Science (Honours), Centre for Electrochemical Research and Analytical Technology, School of Science, Food and Horticulture, University of Western Sydney, March 2001." Bibliography: leaves 62-67.
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Valås, Inge Åsmund. "A Data-intensive Approach to Prediction of Unwanted Events during Oil and Gas Well Drilling." Thesis, Norwegian University of Science and Technology, Department of Computer and Information Science, 2005. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9282.
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Tresselt, Hanne Jahreie. "Filter loss study: loss of hydrocarbons from filter when sampling and storing oil mist and oil vapour samples." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for industriell økonomi og teknologiledelse, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-15065.
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The main purpose of the thesis was to find the best way of storing samples of aerosol from drilling mud on filter.The patterns of loss depend on the properties of the base oil and the concentration of the sample. Most sample is lost during aspiration for high volatility samples, but the degree of loss during storage has similar patterns. Lower concentration samples loose more than higher concentration samples during aspiration.Filters should be taken out of the cassette before weighing rather than weighing the whole cassette with filter.Storage on cellulose acetate plus glass fibre filter combination and on double glass fibre filter have similar patterns, but more sample is lost during aspiration with a double glass fibre filter than with a cellulose acetate plus glass fibre filter combination for EDC Pearl and Sipdrill 2.0. Samples should be stored at refrigerator temperature for higher concentrations (ca. 70 mg/m3) and at room temperature for low concentrations (ca. 20 mg/m3). Plugs do not make much difference.How long a sample can be stored depends on the volatility of the sample, as high volatility (low viscosity) samples tend to lose more during aspiration.
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Bultongez, Kevin Kombo. "Experimental investigation on the effects of channel material, size, and oil viscosity in horizontal mini-channels." Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/35568.
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Master of ScienceDepartment of Mechanical and Nuclear Engineering
Melanie M. Derby
Oil-water separation is an important process in the petroleum industry. This research investigates the use of surface tension forces to improve current oil-water separation technologies. An understanding of oil-water flows in surface tension driven mini-channels is necessary. This work investigates the effects of mini-channel wall material and tube diameter, along with oil viscosity, on flow regimes and pressure drops in mini-channel oil-water flows. A horizontal closed-loop, adiabatic experimental apparatus was constructed and validated using single-phase water. 2.1-mm and 3.7-mm borosilicate glass, 3.7-mm stainless steel and 4.0-mm Inconel tubes, resulting in Eötvös numbers of 0.2, 0.6 and 0.7 were tested. The experimental data were analyzed and compared using two mineral oils (i.e., Parol 70 and 100) with densities of 840 kg/m³ for both and viscosities of 11.7 and 20.8 mPa-s, respectively. Experiments included a wide range of oil superficial velocities (e.g., 0.28-6.82 m/s for glass, 0.28-2.80 m/s for stainless steel and 0.21-2.89 for Inconel) and water superficial velocities (e.g., 0.07-6.77 for glass, 0.07-4.20 m/s for stainless steel and 0.06-3.86 m/s). Flow regimes were observed and classified as stratified, annular, intermittent, and dispersed flow regimes. Effects of tube diameter were observed. For example, the 2.1-mm glass tube had the smaller range of stratified flows and the larger range of annular and intermittent flows compared to the 3.7-mm glass tube. At the same oil and water superficial velocities and relatively the same flow regime, stainless steel and Inconel always displayed higher pressure drop than the glass tube. However, pressure drops were a strong function of flow regime; lowest pressure drops were found for annular flows and highest pressure drops for dispersed flows. Flow regime maps and pressure drop graphs were created. Overall effects of oil viscosity were modest; however, an increase in oil viscosity enhanced flow stability which affected flow regime transition points.
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De, Fazio Juliana Leticia [UNESP]. "Cálcio e ethephon no desenvolvimento e produção de óleo essencial de menta (Mentha Piperita L.), cultivada em solução nutritiva." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/88126.
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A Mentha piperita L., planta aromática da família Lamiaceae, é uma espécie de grande interesse econômico na obtenção de óleos essenciais. Seu óleo é amplamente empregado como aditivo de alimentos, em produtos de higiene bucal e em preparações farmacêuticas. Este estudo objetivou avaliar a influência da variação do nível de cálcio em solução nutritiva, associada à aplicação de ethephon, no desenvolvimento e na produção do óleo essencial de menta. O experimento foi conduzido em casa de vegetação do Departamento de Botânica do Instituto de Biociências, Universidade Estadual Paulista, UNESP, Botucatu, SP. Para tanto, as plantas foram cultivadas em solução nutritiva no 2 de Hoagland & Arnon, contendo 160 mg L-1 de cálcio e na mesma solução com sua redução para 50%, 80 mg L-1 e 90%, 16 mg L-1 e submetidas à pulverização foliar com 100, 200 e 400 mg L-1 de ethephon, onde permaneceram até as datas de colheitas, realizadas aos 46, 76, 106 e 136 dias após o transplante das mudas para a solução nutritiva. O delineamento foi inteiramente casualizado com doze tratamentos, constituídos por três níveis de cálcio e quatro doses de ethephon, quatro repetições e quatro colheitas. A aplicação do ethephon, via foliar, foi realizada em quatro épocas, com intervalos de 30 dias, tendo início aos 31 dias após transplante das mudas para a solução nutritiva. Em cada colheita foram determinados, o comprimento de parte aérea, a área foliar, a matéria seca de lâminas foliares, de caules mais pecíolos, de raízes e total das plantas. Para a análise de crescimento foram determinados os índices fisiológicos, taxa de crescimento absoluto (TCA), taxa de crescimento relativo (TCR), taxa assimilatória líquida (TAL), razão de área foliar (RAF) e área foliar específica (AFE).
Mentha piperita L., an aromatic plant from Lamiaceae family, is a species with great economic interest for producing essential oils. Its oil is extensively employed as food additive, in products of mouth hygiene and in pharmaceutical formulas. This research aimed to evaluate the influence of the calcium level variation in nutritive solution, associated to ethephon application, on the development and in the essential oil yield of mint. The experiment was conducted in the greenhouse at the Bio Science Institute/ Botany Department, UNESP, Botucatu-SP. Thus, all plants were grown in a no 2 Hoagland & Arnon nutritive solution, varying the calcium level in three different proportions: the first group contained the standart level of calcium, of 160 mg L-1 found in this nutritive solution. The second group was grown with Ca2+ reduction in 50%, therefore, 80 mg L-1. The third group was grown with Ca2+ reduction in 90%, therefore, 16 mg L-1. The three groups were submitted to leaf pulverization with 100, 200 and 400 mg L-1 of ethephon. Thus, the plants remained with this treatment until the dates of harvests, which were performed at 46, 76, 106 and 136 days after the transplantation to nutritive solution. The design was completely randomized with twelve treatments constituted of three and four levels of calcium and ethephon, respectively, four replicates and four harvests. The application of ethephon on the leaves first started at the 31st day after the transplantation (DAT) to nutritive solution, and was performed at four epochs, with intervals of 30 days. Shoot length, leaf area, and dry matter of leaf blades, stems plus petioles, roots and total of the plants were determined in each harvest. For growth analysis, it was measured the physiological indexes absolute growth rate (AGR), relative growth rate (RGR), net assimilation rate (NAR), leaf area ratio (LAR) and specific leaf area (SLA).
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Rowland, Sara Michelle. "Recreating a functioning forest soil in reclaimed oil sands in northern Alberta." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/514.
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During oil-sands mining all vegetation cover, soil, overburden and oil-sand is removed, leaving pits several kilometres wide and hundreds of metres deep. These pits are reclaimed by a variety of treatments using mineral soil or a mixed peat and mineral soil as the capping layer and planted with trees with natural colonisation from adjacent sites.
A number of reclamation treatments covering different age classes were compared with a range of natural forest ecotypes to identify the age at which the treatments become similar to a natural site with respect to vegetation composition and key soil attributes relevant to nutrient cycling.
Ecosystem function was estimated from plant community composition, litter decomposition, development of an organic layer and bio-available nutrients. Key response variables including moisture, pH, C:N ratios, bio-available nutrients and ground-cover were analysed by non-metric multidimensional scaling and cluster analysis to discover which reclamation treatments were moving towards or merging with natural forest ecotypes and at what age this occurs.
On reclaimed sites, bio-available nutrients including nitrate generally were above the natural range of variability but ammonium, phosphorus, potassium, sodium and manganese were generally very low and limiting to ecosystem development. Plant diversity was similar to natural sites from 5 years to 30 years after reclamation, but declined as reclaimed sites approached canopy closure. Grass and forb leaf litters decomposed faster than aspen or pine in the first year, but decomposition on one reclamation treatment fell below the natural range of variability. Development of an organic layer appeared to be facilitated by the presence of shrubs, while forbs correlated negatively with first-year decomposition of aspen litter.
The better restoration amendments for tailings sands involved repeated fertilisation of peat: mineral mixtures in the early years of plant establishment, these became similar to a target ecotype at about 25 years. Good results were also shown by subsoil laid over non-saline overburden and fertilised once, these became similar to a target ecotype at about 15 years. Other treatments receiving a single application of fertiliser remain entrenched in the early reclamation phase for up to 25 years.
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Agars, Robert C. "Assessment of the potential environmental effects of soluble hydraulic oil on natural waters." Thesis, [Richmond, N.S.W.] : Centre for Electrochemical Research and Analytical Technology, School of Science, Food and Horticulture, University of Western Sydney, 2001. http://handle.uws.edu.au:8081/1959.7/249.
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A series of physical and chemical analyses were conducted over a fifteen month period to establish the ecological risk, if any, of discharging minewater into aquatic ecosystems. Organic and inorganic analyses were used to determine the extent of contamination of minewater with soluble hydraulic fluids and other contaminant species. Throughout the sampling period the pithead discharge water exhibited a neutral pH and low levels of iron, manganese, zinc and potassium were found. Parallel toxicological and chemical studies identified elevated zinc levels above published toxicity levels for the test species Ceriodaphnia Dubia, but were not confirmed by subsequent study. The presence of organic species in the pit head discharge water was also identified, but the levels were found to be quite variable. Treatment processes involving the detention of the surface minewater and subsequent passage through wetlands exhibited a beneficial effect in reducing pollutant levels prior to disposal. Comparisons of the chemical composition of the minewater discharge with those of local waters were carried out and found to be similar in nature.
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Oisalu, Ott, and Taavi Lõhmuste. "STABILITY ANALYSIS OF A LONGWALL MINING IN NARVA OIL SHALE MINE." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-65372.
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Oil shale industry in Estonia is looking at other mining technologies as alternative to strip mining and room and pillar mining methods. One such alternative to the room and pillar method is the punch-longwall mining method. Enefit Kaevandused AS, one of the major oil shale companies in Estonia, plans to employ this technology in exploiting some of its resources in the near future. This thesis examines the different stability problems related to the planned punch-longwall mining project in Narva oil shale mine. Determining optimal chain pillar dimensions and stability of the punch-longwall highwall slope are the main objectives of this project. Rock mechanical analyses have been done and recommendations are made based on the rock mechanical aspect of the mining process. Taavi Lõhmuste is responsible for the chain pillar stability analysis and Ott Oisalu for the punch-longwall highwall slope stability analysis. It is essential to understand the geology of a certain area in order to make accurate stability assessments. Because of the previously stated requirements, the geology of Estonian oil shale deposit is examined in the first part of the thesis in order to determine the geological and rock mechanical conditions to set the foundation for further analyses. In conclusion, for the part of the highwall slope, a properly designed barrier pillar plays a key role in the stability of the slope. After reviewing and analyzing the results of both highwall slope numerical models, it can be stated that the minimum length for the barrier pillar that still will yield in stable highwall slope is 65 meters. For the part of the chain pillars, in conclusion, it can be determined that optimal chain pillar dimensions that should be suitable, from the stability standpoint, are 6x6 meters for 3-entry system and 7x7 meters for 2-entry system (length x width).
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Ekelund, Åsa. "Metal mobility and transport from an oil-shale mine, Lake Nõmmejärv, Estonia." Thesis, Stockholms universitet, Institutionen för naturgeografi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-195364.
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Mining activities have a large impact on the environment, for example by the release of heavy metals from acid mine drainage and erosion of mine waste. North-eastern Estonia has the largest commercially exploited oil-shale deposit in the world. Waste from the mining processes have led to contamination of groundwater and streams polluted by phenols, oil products, sulphates and heavy metals. This thesis concerns the metal mobility from oil-shale mines in north-eastern Estonia, through water flow in the drainage system directed into Lake Nõmmejärv, which acts as a sedimentation basin for the mining water. A sediment core along with lake bottom surface samples were retrieved and analysed for heavy metals associated with mining. Water samples were collected and analysed for TOC. The sedimentary records show distinctively the change with the high inflow of water. The analysis of heavy metal content does not suggest a high impact on the environment, possibly because of a buffering effect by the limestone bedrock. The contents of heavy metals are somewhat elevated compared to background contents in Swedish lake sediments, but only cadmium and nickel levels are in the range that can be hazardous for the survival of organisms.
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Pinckney, Francis Douglas. "Air-oil mist lubrication of small bore ball bearings at high speeds." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/104537.
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De, Fazio Juliana Leticia. "Cálcio e ethephon no desenvolvimento e produção de óleo essencial de menta (Mentha Piperita L.), cultivada em solução nutritiva /." Botucatu : [s.n.], 2007. http://hdl.handle.net/11449/88126.
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Orientador: Carmen Silvia Fernandes BoaroBanca: Márcia Ortiz Mayo Marques
Banca: João Domingos Rodrigues
Resumo: A Mentha piperita L., planta aromática da família Lamiaceae, é uma espécie de grande interesse econômico na obtenção de óleos essenciais. Seu óleo é amplamente empregado como aditivo de alimentos, em produtos de higiene bucal e em preparações farmacêuticas. Este estudo objetivou avaliar a influência da variação do nível de cálcio em solução nutritiva, associada à aplicação de ethephon, no desenvolvimento e na produção do óleo essencial de menta. O experimento foi conduzido em casa de vegetação do Departamento de Botânica do Instituto de Biociências, Universidade Estadual Paulista, UNESP, Botucatu, SP. Para tanto, as plantas foram cultivadas em solução nutritiva no 2 de Hoagland & Arnon, contendo 160 mg L-1 de cálcio e na mesma solução com sua redução para 50%, 80 mg L-1 e 90%, 16 mg L-1 e submetidas à pulverização foliar com 100, 200 e 400 mg L-1 de ethephon, onde permaneceram até as datas de colheitas, realizadas aos 46, 76, 106 e 136 dias após o transplante das mudas para a solução nutritiva. O delineamento foi inteiramente casualizado com doze tratamentos, constituídos por três níveis de cálcio e quatro doses de ethephon, quatro repetições e quatro colheitas. A aplicação do ethephon, via foliar, foi realizada em quatro épocas, com intervalos de 30 dias, tendo início aos 31 dias após transplante das mudas para a solução nutritiva. Em cada colheita foram determinados, o comprimento de parte aérea, a área foliar, a matéria seca de lâminas foliares, de caules mais pecíolos, de raízes e total das plantas. Para a análise de crescimento foram determinados os índices fisiológicos, taxa de crescimento absoluto (TCA), taxa de crescimento relativo (TCR), taxa assimilatória líquida (TAL), razão de área foliar (RAF) e área foliar específica (AFE).
Abstract: Mentha piperita L., an aromatic plant from Lamiaceae family, is a species with great economic interest for producing essential oils. Its oil is extensively employed as food additive, in products of mouth hygiene and in pharmaceutical formulas. This research aimed to evaluate the influence of the calcium level variation in nutritive solution, associated to ethephon application, on the development and in the essential oil yield of mint. The experiment was conducted in the greenhouse at the Bio Science Institute/ Botany Department, UNESP, Botucatu-SP. Thus, all plants were grown in a no 2 Hoagland & Arnon nutritive solution, varying the calcium level in three different proportions: the first group contained the standart level of calcium, of 160 mg L-1 found in this nutritive solution. The second group was grown with Ca2+ reduction in 50%, therefore, 80 mg L-1. The third group was grown with Ca2+ reduction in 90%, therefore, 16 mg L-1. The three groups were submitted to leaf pulverization with 100, 200 and 400 mg L-1 of ethephon. Thus, the plants remained with this treatment until the dates of harvests, which were performed at 46, 76, 106 and 136 days after the transplantation to nutritive solution. The design was completely randomized with twelve treatments constituted of three and four levels of calcium and ethephon, respectively, four replicates and four harvests. The application of ethephon on the leaves first started at the 31st day after the transplantation (DAT) to nutritive solution, and was performed at four epochs, with intervals of 30 days. Shoot length, leaf area, and dry matter of leaf blades, stems plus petioles, roots and total of the plants were determined in each harvest. For growth analysis, it was measured the physiological indexes absolute growth rate (AGR), relative growth rate (RGR), net assimilation rate (NAR), leaf area ratio (LAR) and specific leaf area (SLA).
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Yasuda, Naoki. "Hydraulic Performance of the Seepage Collection Ditches at the Albian Sands Muskeg River Mine." Thesis, University of Waterloo, 2006. http://hdl.handle.net/10012/2877.
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The tailings pond at the Muskeg River Mine is a large structure with a 11 km-long ring dyke that contains process affected water (PAW) and tailings sand. The dyke is made of permeable tailings sand and therefore it is equipped with seepage collection ditches that are designed to collect water from drains in the dyke but also to intercept seepage water not collected by the drains and transmit it to the seepage pond for recycling. The effectiveness of this seepage collection system was examined at the downgradient end of the tailings pond (Study Area) where near-surface permeable sand is present. Piezometric level measurements were performed and water samples were collected from a network of 21 piezometers and drive points, and at several other critical locations. Concentrations of major chemical tracers of PAW such as naphthenic acids (NAs) show signs of migration of PAW in the permeable sand deposit, beyond the dyke. This interpretation is supported by stable O and H isotope analysis of water. The interpretation of the piezometric and chemical data revealed that the PAW has migrated past the Inner Ditch but not beyond the Outer Ditch. Elevated hydraulic heads beyond the Outer Ditch prevented further migration. Groundwater locally converges and discharges as surface water in the wet area between the two ditches. Thus, the collection ditch system is currently working effectively to contain PAW.
Numerical modeling of the Study Area was able to reasonably recreate the observed hydraulic conditions. Based on these simulations, it is possible that PAW may be migrating through a permeable layer of sand under the bottom of the dyke and pond, and eventually discharging into the wet area between the ditches. The estimated amount of PAW seepage discharged into the wet area is small compared to the total dyke drainage collected by the ditches.
These conditions described above, however, may change with the progress of the current dyke expansion work. The wet area between the ditches will be buried and the local hydraulic condition is expected to alter. This may reverse the hydraulic gradient across the Outer Ditch and perhaps will facilitate migration of PAW beyond the Outer Ditch. It is recommended that the following key chemical parameters be used in future groundwater quality monitoring efforts to track PAW migration at the Muskeg River Mine: Na+ Cl- , SO42- , and Ca2+ ions, stable isotopes of hydrogen and oxygen, and Naphthenic acids (NAs. )
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Salzman-Gubbay, Gideon J. "Earth, Air, Water, Oil: Regulating Fracking in the Monterey Shale with Health and Environment in Mind." Scholarship @ Claremont, 2014. http://scholarship.claremont.edu/pomona_theses/112.
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“Earth, Air, Water, Oil: Regulating Fracking in the Monterey Shale with Health and Environment in Mind,” explores how hydraulic fracturing regulation in California’s oil-rich Monterey Shale will impact regional public health, including groundwater and air quality. This is achieved through a combination of case study and policy analysis on both the state and national level.
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Knieschewski, Arno [Verfasser]. "Energy efficiency rating of cooking fume extractors based on captured and filtered oil mist / Arno Knieschewski." Düren : Shaker, 2020. http://d-nb.info/1215461844/34.
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Jančová, Nikola. "Látky terpenické povahy v rostlinách máty a jejich ovlivnění elicitací." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2017. http://www.nusl.cz/ntk/nusl-295689.
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Diploma thesis is focused on study of compounds of terpenic nature in mint plants. Terpenic compounds are volatile hydrocarbons formed by several isoprenoid units with low molecular weight which cause the typical smell of plants. Presence of these compounds cause that plants seem to be fungicidal, bactericidal and insecticidal. Due to these properties, they can be used as botanical pesticides which are not toxic and no resistant organisms occur. Each plant contains relatively low concentrations of these compounds and therefore elicitors must be used for the increasing of terpenes amount. Elicitors activate defensive mechanisms in the plant leading to higher defense abilities and production of secondary metabolites. The identification and quantification of analytes was determined by gas chromatography in connection with mass spectrometry.
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Moreno, Oscar Ray. "Investigation and development of oil-injection nozzles for high-cycle fatigue rotor spin test." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Mar%5FMoreno.pdf.
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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, March 2005.Thesis Advisor(s): Raymond Shreeve, Garth Hobson. Includes bibliographical references (p. 91-93). Also available online.
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Thompson, Andrew P. "Effect of pressure and temperature on oil mist sprays used for blade excitation in high cycle fatigue testing." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2006. http://library.nps.navy.mil/uhtbin/hyperion/06Jun%5FThompson_Andrew.pdf.
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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, June 2006.Thesis Advisor(s): Raymond Shreeve. "June 2006." Includes bibliographical references (p. 131). Also available in print.
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Martin, Alexis. "Modélisation de saumures carbonatées et caractérisation hydrogéologique de la mine Niobec, Saint-Honore, Québec : /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1993. http://theses.uqac.ca.
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Vonderheide, Christopher M. "Laser velocimetric flow mapping and characterization of oil mist nozzles used for blade excitation in high cycle fatigue testing." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Sep%5FVonderheide.pdf.
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Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, September 2005.Thesis Advisor(s): Dr. Raymond Shreeve, Dr. Garth Hobson. Includes bibliographical references (p. 61). Also available online.
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Zedlitz, Jesper [Verfasser]. "Konzeptuelle Modellierung mit UML und OWL – Untersuchung der Gemeinsamkeiten und Unterschiede mit Hilfe von Modelltransformationen / Jesper Zedlitz." Kiel : Universitätsbibliothek Kiel, 2013. http://d-nb.info/103734278X/34.
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Mierendorff, Hanco-Gisbert. "Chemische Zusammensetzung des ätherischen Öls von Eriocephalus tenuifolius DC. (Cape Chamomile Oil) ein Vergleich von Handelsölen mit Ölen aus Wildpflanzen und Stecklingskulturen /." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=982353154.
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Townley, Paul Joseph. "Preliminary investigation for underground storage of pipeline gas in the Bruer and Flora pools, Mist gas field, Columbia County, Oregon." PDXScholar, 1985. https://pdxscholar.library.pdx.edu/open_access_etds/3542.
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Northwest Natural Gas Canpany has proposed to convert the Bruer and Flora pools of the Mist Gas Field in west-central Columbia County, Northwestern Oregon, to pipeline gas storage reservoirs. Conversion to underground storage of pipeline gas in these depleted gas reservoirs would be the first in the Pacific Northwest. The Bruer and Flora Pools are fault trapped within the Cowlitz Formation. The shales overlying the Cowlitz Formation create a local seal for these gas reservoirs. X-ray diffraction and density log measurements suggest that the clay in these shales is primarily composed of smectite, which provides an excellent caprock seal.
The reservoir rock of the Bruer and Flora Pools is the arkosic Cl ark and Wilson Sand. An average weighted grain density for the sand is 2.65 g/cm3. The abundance of potassium feldspar in the sand, hence K40, creates a background gamma radiation for the sand roughly equal to that of the shale, making the sand and shale virtually indistinguishable on the gamma ray log.
Bottan Hole Temperatures (BHT), which were recorded on open hole logs, indicate the Bruer Pool is 7°C (20°F) wanner than the Flora Pool, even though the Flora Pool is deeper. This temperature anomaly may be the result of equipment variation. A calibrated temperature survey would remove any discrepancies. A comparison of the thermal gradient determined in a previous study of the Oregon Coast Range and a gradient determined using BHT, suggest that BHT provide a good approximation of formation temperature.
Utilizing the formation water analysis determined from four different wells in the Mist Gas Field, average total dissolved solids was found to be 24, 444 mg/l. Of the four analyses, the sample from Well CC#6 R/D2 is considered to be the most representative of the Bruer and Flora fools formation waters. Analysis of the four samples using the Palmer System suggests that the formation water of the Cowlitz Formation is in the early stages of sea water diagenasis.
Formation water resistivity (Rw) was determined using a chemical and spontaneous potential analysis. Rw derived using chemical analysis averaged 0.175 ohm-meters and is considered the ITDst precise. Water saturation determined using the Archie saturation equation averaged 47.5% and ranged from 26.4 to 80.0% for the zone 814-836 meters (2670-2742 feet) in CC#10. These results are similar to those determined by the Thermal Time Decay (TDT) log.
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Oehler, Beatrice. "TRPA1 ist funktionell in Melanomzellen exprimiert, hat jedoch keinen Einfluss auf die verminderte Proliferation der Zellen nach Stimulation mit Senföl oder Zimtaldehyd." Doctoral thesis, Universitätsbibliothek Leipzig, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-116482.
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Melanome zählen zu den zehn häufigsten Tumorentitäten weltweit. Bei frühzeitiger Diagnose ist eine Exzision im Gesunden kurativ. Sobald eine Resektion im Gesunden jedoch nicht mehr möglich ist, sinken die Heilungschancen drastisch. Maligne Melanome sprechen wenig auf konventionelle Tumortherapien wie Radiatio und zytostatische Chemotherapie an. Daher werden neue Therapieoptionen in der Melanomtherapie getestet. Neueste Ansätze beziehen sich auf die Modulation von Immunzellen mittels monoklonaler Antikörper sowie die Modifikation der Signaltransduktion über die Mitogen-aktivierte Protein Kinase Kinase (MAPKK = MEK), BRAF und c-KIT. Auch Ionenkanäle stellen eine vielversprechende, zukünftige Option in der Behandlung maligner Melanome dar. Ich konnte zeigen, dass neben der bereits beschriebenen funktionellen Expression des „transient receptor potential“ Kanals TRPM8 in Melanomzelllinien auch TRPA1 in verschiedenen Melanomzelllinien exprimiert und funktionell ist. Die Phytopharmaka Senföl (Allylisothiozyanat; AITC) und Zimtaldehyd zeigen in Melanom-Modellen antitumoröse Effekte. Zudem sind beide Substanzen potente Stimulatoren von TRPA1. In dieser Arbeit wurde untersucht, ob AITC und Zimtaldehyd TRPA1-vermittelt die Proliferation, Apoptose und Migration von Melanomzellen beeinflussen. Das Vorkommen von TRPA1 in verschiedenen Melanomzelllinien wurde auf molekularbiologischer Ebene, mit fluorometrischen Bestimmungen des TRPA1-vermittelten Ca2+-Einstroms sowie in elektrophysiologischen Messungen nachgewiesen. Anschließend wurde die funktionelle Relevanz von TRPA1 bezüglich tumorhemmender Eigenschaften geprüft. Durch die Anwendung von TRPA1-Blockern konnte die AITC- und Zimtaldehyd-induzierte Verminderung der Proliferation nicht aufgehoben werden. Auch bezüglich der Migration und Apoptose konnte keine Korrelation zu einer TRPA1-Modulation festgestellt werden. Daher scheinen die durch AITC und Zimtaldehyd induzierten Effekte höchstwahrscheinlich nicht durch TRPA1 vermittelt zu werden.
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Williams, Charles L. "Environmental impact on the Northern Persian Gulf: a mine drift and chemical spill study centered on Iraq's oil terminals using Navy's ocean-atmospheric physical and chemical models." Thesis, Monterey, Calif. : Naval Postgraduate School, 2007. http://bosun.nps.edu/uhtbin/hyperion.exe/07Mar%5FWilliams%5FCharles.pdf.
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Thesis (M.S. in Meteorology and Physical Oceanography)--Naval Postgraduate School, March 2007.Thesis Advisor(s): Peter C. Chu. "March 2007." Includes bibliographical references (p. 119-125). Also available in print.
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Schwartz, Julie Ann. "Systemic and immune toxicity induced by low concentration chronic fuel oil exposure in American mink (Mustela vison), a surrogate model for the Southern sea otter (Enhydra lutris nereis) /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.
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Tlapák, Michal. "Technologické, ekonomické a ekologické aspekty použití mazání mlhou." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2009. http://www.nusl.cz/ntk/nusl-228837.
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The assessment of MQL technology application in reaming process was elaborated in this diploma work. The evaluation of energy intensity was carried out in terms of specific cutting force during reaming of austenitic stainless steel work piece by using HSS reamers. The comparison of economic costs in the case of the application of MQL technology in production was made. Confrontation of oil mist removal principles. At the conclusion the evaluation of ecological benefits for the environment and the positive influence on the working environment cleanness was defined.
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Soden, Michael. "Dynamische Modellanalyse von Metamodellen mit operationaler Semantik." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät II, 2015. http://dx.doi.org/10.18452/17168.
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Metamodellierung im Sinne der Meta Object Facility (MOF) stellt eine Methode für die strukturelle Definition der abstrakten Syntax von Modellierungssprachen und Modellen im Softwareentwicklungsprozess dar. Um Modellsimulation und dynamische Analysen für metamodellbasierte Sprachen zu unterstützen, fehlt es an einem Kalkül zur operationalen Semantik. In dieser Arbeit wird ausgehend von MOF die Aktionssemantik MActions entwickelt, die die Definition von operationaler Semantik als Verhalten in Metamodellen ermöglicht. Diese Erweiterung geht einher mit der Beschreibung von Laufzeitmodellen sowie Zuständen und Parallelitätseigenschaften, so dass eine Verifikation von dynamischen Eigenschaften möglich wird. Zu diesem Zweck wird mit der Linear Temporal Object Constraint Language (LT-OCL) exemplarisch eine prädikatenlogische Temporallogik entwickelt, die eine metamodellunabhängige Analyse für ausführbare Modelle erlaubt. Dabei ist die Semantik von temporalen Ausdrücken über Zuständsänderungen von (aufgezeichneten) Ausführungsläufen beschrieben, wobei eine Linearisierung parallele Änderungen zusammenführt. Als weiteren Anwendungsfall der dynamischen Analyse untersuchen wir die Relation zum Verhaltensvergleich im Sinne der Bisimulationstheorie. Metamodelle, Aktionssemantik und Temporallogik werden mittels einer erweiterten Abstract State Machine (ASM) formal beschrieben und kommen in zwei Fallstudien zur Anwendung (Timed Automata und C#).Object-oriented metamodelling as defined by the Meta Object Facility (MOF) provide a means to describe the structure of models and the abstract syntax of modelling languages at various stages in a software development process. However, MOF lacks concepts for the definition of operational semantics and there is no support for dynamic model analysis based on the semantics and abstract states of a language definition. This thesis investigates on extending the metamodelling framework with an action semantics - the MActions - to support the definition of operational semantics in metamodels and enable simulation as well as verification of dynamic properties. For this purpose, runtime models are incorporated with semantics for states, time, and properties of parallelism that allow a generic analysis solely bound to a certain metamodel definition. Furthermore, we develop the Linear Temporal Object Constraint Language (LT-OCL) to perform a dynamic analysis of execution runs based on the executable models. The semantics of this temporal predicate logic is bound to state changes of (recorded) execution traces that are linearizations of parallel changes of the runtimes model. This establishes the link to the theory of bisimulation as a second application case of dynamic analysis. Abstract State Machines (ASM) have been used to formally define the action language in conjunction with metamodels and the temporal logic. As proof of concept of the whole approach, the framework has been implemented and applied to two languages as case studies (namely Timed Automata and C#).
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Meyer, Julia. ""The owl hugs me in the forest" : Children's Experiences and Educators' Perceptions of Learning in a Swedish Mini-Forest Garden." Thesis, Linköpings universitet, Institutionen för beteendevetenskap och lärande, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-158203.
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In recent years, there has been converging evidence on the relation between nature experiences and learning. Although outdoor experiences are not just seen as leisurely activities anymore, barriers, such as lack of resources or travel time can hinder the propagation of more outdoor educational programs. This study explores a relatively new outdoor educational setting that can help overcome these difficulties by decreasing the amount of resources, input and energy necessary to set up such measures: the educational forest garden. With lower maintenance in creating an environment that resembles an authentic ecosystem, the question remains if forest gardening can foster similar learning outcomes than those reported in other educational settings. A qualitative study in a Swedish mini-forest garden was employed to explore what types of learning are possible in this new type of setting. Interviews with two educators and eight children were conducted to find out what perceptions and experiences they communicate after spending time in the mini-forest garden. The educator’s ideas were compared with children’s accounts and observational notes on their behavior to see if there was a difference in perception and experience. Examples for learning were found in three different dimensions: cognitive, emotional and social. The explored categories were ecological literacy, language learning, attention; being comfortable outdoors, respect and care, awareness of surroundings, co-creation, teacher-student interaction, gender differences and free play and imagination. The findings indicate an overlap between teacher’s and children’s experiences and perceptions in almost all categories and similar beneficial learning outcomes with forest gardening to other outdoor educational endeavors. Along with the potential for self-development, forest gardening may be a new way to successfully teach in the outdoors with less input or resources. Although a small scale study that should not be generalized, the study gives insight to educators’ and children’s voices in a new outdoor educational setting and can help overcome the lack of children’s voices in research in general. At the same time, it adds to the limited amount of research on forest gardening and potentially helps to increase the popularity of forest gardening as a new outdoor educational method.
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Backhaus, Karsten. "Das dielektrische Verhalten der Öl-Papier-Isolierung bei Belastung mit hoher Gleichspannung." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-228992.
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Basierend auf den physikalischen Eigenschaften der unterschiedlichen ölintrinsischen und injizierten Ladungsträger wird ein neues Leitfähigkeitsmodell für Isolieröl und -papier für die Belastung mit hoher Gleichspannung aufgestellt. Das Modell wird mit der Wahl geeigneter Randbedingungen für das elektrische Feld und der Teilchenströme auf die Poisson-Nernst-Planck-Gleichung übertragen. Es steht damit ein Werkzeug zur Verfügung, das dielektrische Verhalten der Öl-Papier-Isolierung zu modellieren, dessen Parameter auf den physikalischen Ladungsträgereigenschaften wie Mobilität und Diffusion basieren. Mit dessen Hilfe werden sowohl die nichtlineare Leitfähigkeit als auch das Durchschlagverhalten als deren Extrapolation feldstärkeabhängig erklärt.
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Kubitza, Christoph Alexander [Verfasser], Matin [Akademischer Betreuer] Qaim, Bernhard [Gutachter] Brümmer, Krisztina [Gutachter] Kis-Katos, and Miet [Gutachter] Maertens. "Land-use change and rural development in Indonesia: Economic, institutional and demographic aspects of deforestation and oil palm expansion / Christoph Alexander Kubitza ; Gutachter: Bernhard Brümmer, Krisztina Kis-Katos, Miet Maertens ; Betreuer: Matin Qaim." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://d-nb.info/1160753563/34.
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Kubitza, Christoph Alexander Verfasser], Matin [Akademischer Betreuer] [Qaim, Bernhard [Gutachter] Brümmer, Krisztina [Gutachter] Kis-Katos, and Miet [Gutachter] Maertens. "Land-use change and rural development in Indonesia: Economic, institutional and demographic aspects of deforestation and oil palm expansion / Christoph Alexander Kubitza ; Gutachter: Bernhard Brümmer, Krisztina Kis-Katos, Miet Maertens ; Betreuer: Matin Qaim." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://nbn-resolving.de/urn:nbn:de:gbv:7-11858/00-1735-0000-002E-E40D-9-9.
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Kunkel, Luisa [Verfasser], and Frank [Akademischer Betreuer] Ohl. "Untersuchungen zur Perzeption musikalischer Parameter von Cochlea-Implantat-Trägern mit den Sprachkodierungsstrategien ACE und MP3000 im Vergleich zu normalhörenden Probanden / Luisa Kunkel. Betreuer: Frank Ohl." Magdeburg : Universitätsbibliothek, 2014. http://d-nb.info/106791644X/34.
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Hewitt, Mark S. "Alternative rehabilitation techniques and sustainable outcomes from mining using appropriate environmental management and mine closure planning in an arid region of Western Australia." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2007. https://ro.ecu.edu.au/theses/250.
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The subject of this thesis is the development of alternative approaches to environmental management and mine closure plans using case examples of the Big Bell/Cue Mining District and as a working example, an area of unconfined washout of historical gold-mine process tailings located in this arid inland region of Western Australia. This is considered appropriate in the light of the social and political thrust for industry to develop simultaneously positive economic, social and environmental outcomes from their activities. The Big Bell mining operation ceased mining in June 2003 and the Mine Closure Plan reflected a classical approach of minimization of public liability and strict compliance with legislative requirements. During the life of the modern mine the approach to rehabilitation was similarly classical in its approach It is intended for this document to inform the mining industry using the case example of the now closed Big Bell Mine as to how greater long-term outcomes may have been achieved for the State and the region for the future. This thesis specifically investigates alternative ways to approach rehabilitation in arid areas of Western Australia using the washout area as an example and trial area. This thesis has approached the issue by addressing the quantification of what has occurred through the gathering of baseline data of the case study area and then by the implementation of a series of relevant trials to identify appropriate eco-functional process-sensitive methods for rehabilitation as an alternative to current industry practice. Trials investigating the use of "retention banks" and "clay/seed balls" and the use of ex-mine milling waste carbon were conducted to investigate relevant possible techniques suitable for arid mine-site waste dump rehabilitation. Data analysis indicated that the main reason for the high level of degradation within the case study area is due to the smothering effect of the fine clayey tails cover and due to acidity of the tailings. A detailed examination of 92 soil samples found water infiltration of tails-washed areas as half that of control areas. Acidity of alluvium has declined from pH 5.2 to 3.8. The acidity has penetrated at depth to hardpan. Trials were commenced to rehabilitate the area using a combination of earthworks (retention banks and· scarification), pH- adjustment (using ex-mill carbon and crushed lime), and the use of native seed pelletised into clay-balls. The introduction of ex-mill carbon was shown to be effective in ameliorating pH in the tails wash area and improving its capacity to regenerate. Considering it is a widely available waste product with the gold mining industry it should be seriously considered in its application for rehabilitation purposes, and specifically in areas affected by severe acidification and desertification particularly by mismanaged tailings with pyrite content. The use of clay balls should also be subjected to further investigation. It is at least equal to the traditional use of raw seed and fertilizer with immediate and abundant rainfall. As this almost never occurs, it should prove to be superior, in delivering higher rates of viability for seed used. The thesis then attempts to integrate this study within the context of the wider issues of environmental management, specifically the best practice of mine closure plans and the adoption of sustainable economic, social and environmental outcomes from mining as an integral part of responsible operational environmental management plans. The thesis argues that the environmental management planning and specifically the Mine Closure Plan should not waste the myriad of opportunities that are the by-product of mining for the long-term sustainable benefit of the wider region. It is argued that if mining companies are serious about sustainability, then they cannot continue with short-term cycles of mining and closure. However to be realistic it will take concerted willingness from all stakeholders to pursue these outcomes. While a given mining operation can offer extensive resources and assets to support this approach the commercial and legislative pressures of core mining activities necessarily mean that mines are in fact encouraged to simply return the environment back to as natural state after operations are complete. Invariably this means hundreds of millions of dollars of infrastructure are levelled and scrapped to avoid all future liability, whilst the potential for sustainable outcomes is essentially ignored. The same Government that enforces the Mining Act and has a State Sustainability Strategy imposes the conditions which create unimaginative classical mine closure plans. Government, industry and the residents of regions must work together to seriously develop sustainable outcomes to mining.
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Stotz, Julia [Verfasser]. "Videojournalismus in öffentlich-rechtlichen Regionalmagazinen : eine Evaluation des Umfangs und der Qualität des Videojournalismus im Vergleich mit arbeitsteiligen Produktionen am Beispiel der "Lokalzeit Köln" (WDR), der "Lokalzeit OWL" (WDR) und der "Hessenschau" (HR) / Julia Stotz." Dortmund : Universitätsbibliothek Technische Universität Dortmund, 2011. http://d-nb.info/1018099069/34.
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Chiu, Chih-hao, and 邱志浩. "The genetic and growth period variation of yield, volatile oil and glandular trichomes of mint." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/50160066585112378821.
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碩士國立中興大學
農藝學系所
98
Twenty-three mint collections were collected in Taiwan to investigate the yields of shoot fresh weight, volatile oil and which’s components and to analyze the variation among collections and annual harvests. The yields of fresh weight and volatile oil between leaf and stem were also compared, and fresh weight ratio of leaf versus stem was estimated. Furthermore, the correlation of volatile oil components, tissue and agronomic traits were estimated. Finally, the yields of fresh weight and volatile oil during growth period were studied. According to ANOVA results, there is significant among collections in new and ratoon cropping and yields of fresh weight, volatile oil and which’s components, and remarked interaction between collections and cropping years is also significant. Generally, the yields of fresh weight, volatile oil and components in ratoon cropping were higher than new cropping. The fresh weight, volatile oil and fresh weight ratio of leaf versus stem among collections were significant. After observed the distribution and amount of leaf epidermal glandular trichomes, 12 collections have capitate and peltate glands at upper and lower epidermal, but the distribution is various. The amount of peltate glands at lower epidermal were more than upper whereas the upper and median leaf were more than lower. The fresh leaf weight positively correlates to leaf and plant volatile oil content, and the volatile oil content of leaf positively correlates to plant volatile oil, menthone, menthol and α-pinene. The fresh weight ratio of leaf versus stem positively correlates to plant volatile oil and menthol content. The amount of peltate glands in different leaf positions positively correlates to volatile oil and menthol content. The menthone content was positive correlation with amount of peltate glands in upper and median leaf, but there were no significant correlation between menthone content and amount of peltate glands in lower leaf. The results elucidate that the collections carried high leaf-stem fresh weight ratio and more leaf peltate glands have high plant volatile oil and menthol content. Compare the fresh weight and volatile oil in different growth period, the yields of collections 16 and 18 increased with days after transplanting （DAT）. Until DAT 146（full bloom stage）, fresh weight, volatile oil and menthol content were highest. Collection 10 was not at reproductive growth in this study and however the fresh weight, volatile oil and menthone content arrived maximum before senescence. Finally, we suggest that the optimal harvest time is between early to late bloom.
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Huang, Rex, and 黃志龍. "Study on reducing oil mist concentration." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/92859099207014203480.
Full textAbstract:
碩士國立清華大學
動力機械工程學系
88
Our work is to observe how oil mist is generated in grinding operations, find out the major factors of oil mist formation, and propose some measures and guidelines reducing worker exposure to oil mist. The mechanism of oil mist formation mainly consists of fast motion of grinding wheel, high shear stress and heat. Increasing the velocity of grinding wheel and material removal rate give rise to thicker oil mist concentration. The larger flow rate of oil-based grinding fluid enhances cooling efficiency and then lowers oil mist concentration resulting from heat. It is not helpful to alter the angles of nozzles in suppressing oil mist. The most efficient methods of controlling air quality in manufacturing plants include installation of air cleaners, enclosure of machines, frequent air exchange between factories and outdoors or using different grinding fluids with low misting property. Besides, adding mist suppressants like PIB is one of turnkey solutions to decrease oil mist concentration. Experiments on suppressing oil mist from grinding operation show that PIB and PEG reduce mist concentration of oil-based and water-based grinding fluids respectively.
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Thorley, URSULA. "Open Pit Mine Planning: Analysis and system modeling of conventional and oil sands applications." Thesis, 2012. http://hdl.handle.net/1974/7577.
Full textAbstract:
In the last decade mineable oil sands production in Canada has grown rapidly. Constraints on the planning and design processes employed by surface mining oil sands operations vary in distinct ways from other commodities mined by both hard and soft rock open pit methods. The unique waste handling needs, including tailings disposal, of contemporary oil sands mining requires specific planning considerations.
It is the purpose of this research to analyze and document a conventional hard rock, metal mine planning system, and contrast this with the unconventional mine planning system used by oil sands mines. Systems activity models of both the conventional and unconventional systems are developed in support of documenting and contrasting the two systems.
Constraints unique to oil sands mine planning are identified and their impact on the oil sands mine planning system are documented. The impacts of challenging waste handling and storage requirements and a uniquely prescriptive regulatory environment defining mineable ore are identified as key constraints.
The research concludes with a proposal for a new planning system to better support the planning of oil sands mines. The proposed system respects the unique waste management considerations in oil sands planning and revisits the current regulatory approach to ensuring resource recovery. The proposed system is compatible with traditional approaches to economic analysis in open pit planning, and with emerging best practices to manage technical and economic uncertainty, improve project optimization, and develop robust mine plans.Thesis (Ph.D, Mining Engineering) -- Queen's University, 2012-10-02 17:52:18.223
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SUNG, Sz-Huei, and 宋思慧. "Exploration of Mind- Oil Painting Study of SUNG,Sz-Huei." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/5q8mv5.
Full textAbstract:
碩士國立臺灣師範大學
美術學系
103
A delicate balance among the body, mind and soul has been an ultimate pursuit of all mankind. People have struggled to calm down with outward interference, therefore, how to properly transform the ripple of our inner core into a peace would be certainly a great issue to us. The author constructed a “mind place” in paintings through a profound talk with herself. It makes the train of thinking roam on the sideline with different perspective toward difficulties, furthermore helps us pick up the connection between ourselves and the universe in conscious level, to open up our inner spirituality after a better comprehension of life. The objective of this study is to acquire the inner peace under various emotions and face the mood originally suppressed by ourselves, via the paintings showing how we react the life under different circumstances. It drives us to see ourselves in other point of view with more magnanimous attitude then to handle every presence. The more the inside balance ball becomes tranquil, the better we master ourselves. The paintings provide another outlet of dispersing her emotion that cannot be expressed by words, especially that the process of painting itself is a best time of settling herself and ruminating life experience. By means ofthe display of the pictures, the author expects that people are able to escape their bustling life and listen to their own inner voice, giving rise to trigger a further enlightenment.
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Lee, Sung-Chan, and 李松展. "Combination of oleophilic/oleophobic filter materials for oil mist remover." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/vbwevu.
Full textAbstract:
碩士國立臺灣大學
應用力學研究所
107
Fine particulate matter (PM2.5) is a critical and imperative problem in Asia. United Nation International Agency for Research on Cancer (IARC) had been considered it as 1A carcinogen, which means the substance is carcinogenic to human. According to the latest TEDS 9.0, it shows ratio of domestic usage and restaurant accounts for 17.13％ and 6.39 ％ of total PM2.5 emission respectively. The proportion is even higher than power supply industries which is 3.64％ of total emission. Therefore, it is crucial to deal with oil mist problem. Fibrous filter plays a crucial role in the market. However, the performance during loading and the difference of oleophilic and oleophobic remains poorly known. Hence, this study not only researches the performance of the material with different surface energy but also develops the better combination design in the market. The research first concentrated on the performance of one commercial high efficiency particulate air (HEPA) filter during loading. Though electrostatic property was able to enhance the efficiency from 85.5％ to 99.7％, efficiency shrank sharply from 98.6％ to 88.3％ within 35 minutes owning to the shedding effect of filtered oil. Furthermore, most of commercial filter is oleophilic filter. Based on previous studies, there is only a few researches related to oleophobic filter; further, the penetration distribution during oil has not been discovered. Thus, here I not only presented the change of penetration distribution and pressure drop during loading but also divided the results into different characteristic regions. Last but not least, one better combination (oleophilic/-phobic) has been discovered and further applied it to improve the performance of HEPA filter, which prominently extended the time of efficiency above 90％ from 35 minutes to 215 minutes under the tested condition (CMD:265 nm; GSD:1.65; Concentration:5x106 counts/cm3).
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"An evaluation of the use of natural stable isotopes of water to track water movement through oil sands mine closure landforms." Thesis, 2014. http://hdl.handle.net/10388/ETD-2014-03-1466.
Full textAbstract:
Surface mining of oil sands results in extensive land disturbance, earth movement and water usage. After mining, the disturbed landscapes must be reconstructed and reclaimed as natural landforms. There are numerous challenges associated with understanding the responses of these landforms over time, including a need to track and characterize water movement through closure landforms to understand the hydrological responses of these landforms over time. This study attempted to use natural stable isotopes of water (δD and δ18O) to identify and characterize source waters from various closure landforms at an oil sands mine site.
The study area is Syncrude‟s Mildred Lake mine, an open pit oil sands mine located in northern Alberta. A variety of groundwater, surface water and soil samples from a variety of landforms (overburden dumps, composite and mature fine tailings areas, tailings sand structures and freshwater reservoirs) were collected in an attempt to fully represent the isotopic distribution of waters across the mine site. Laboratory analysis of δD and δ18O was done on all samples.
The local meteoric water line first established by Hilderman (2011) was redeveloped with additional precipitation data and calculated to be δD=7.0(δ18O) -18.6‰. A natural evaporation line having a slope of 5.3 was calculated for the mine site with samples collected from three surface water ponds on the mine site.
Five primary source waters were identified on the mine site: process affected water/tailings, rainfall, snow, interstitial shale water and Mildred Lake water. It was found that these sources of water generally have unique natural stable water isotope signatures. Process affected water at the site generally had an enriched signature compared to other mine waters. The enrichment was attributed to fractionation from the recycle water circuit and natural evaporation.
The characterizations of these source waters were then used in several hydrogeological examples to demonstrate that natural stable water isotopes can be applied to water balance estimates and to identify water movement processes related to closure landforms.
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Mota, Íris Alves. "Variation of yield and composition of essential oils from Mint and Basil in response to mycorrhizae bio-elicitor and hydric stress." Master's thesis, 2017. http://hdl.handle.net/10198/18292.
Full textAbstract:
Hoje em dia, perante a realidade das alterações climáticas, manifestas, por exemplo, nas mudanças nos padrões de precipitação e temperaturas extremas, torna-se necessário encontrar novos métodos de cultivo de plantas medicinais e aromáticas (MAP), uma vez que o clima tem grandes implicações para o metabolismo vegetal. O aproveitamento da água toma particular importância em climas áridos ou semi-áridos como é exemplo o da região Mediterrânica. Uma consequência comum associada à ocorrência de stress hídrico é a diminuição da biomassa que, no contexto do cultivo, resulta numa poupança de água que não compensa a perda de rendimento. No entanto, na última década, a aplicação de fungos micorrízicos arbusculares (AMF) tem sido considerada uma estratégia importante para contrariar os efeitos do stress hídrico, melhorando simultaneamente o rendimento e qualidade das culturas. No presente estudo, uma experiência fatorial baseada no randomized complete block design com três fatores foi realizada para investigar o efeito de AMF e do stress hídrico sobre a composição do óleo essencial (OE), rendimento, características fisiológicas e morfológicas da menta (Mentha sp.) e manjericão (Ocimum basilicum L. cv. Genovese Gigante). Os fatores incluíram a inoculação de um AMF (Glomus intraradices), um nível de irrigação (stress hídrico leve (60% de capacidade de campo)) e a interação de ambos, AMF e stress hídrico. Adicionalmente examinaram-se os efeitos da secagem das plantas e da colheita em duas alturas diferentes (inverno e final da primavera) na produtividade e qualidade dos óleos essenciais.
Inicialmente, as sementes foram germinadas e as plantas transplantadas e transferidas para uma estufa, permitindo melhor controlo das condições do meio. No decorrer da experiência, diferentes características funcionais foram registradas para obter informações relacionadas à influência do AMF e do stress hídrico no desenvolvimento das plantas. Após cada colheita, o rendimento dos óleos essenciais foi registrado e finalmente estes foram analisados com o auxílio de CG e CG-EM.
Em todas as amostras os principais constituintes dos OE para a menta foram o óxido de piperitenona (22%-91%) e para o manjericão o Eugenol (1%-51%) e o Linalool (18%-60%). A maior quantidade de óxido de piperitenona (91%) foi obtida na 1ª colheita com plantas sob stress hídrico e posteriormente secas. Relativamente aos compostos do manjericão, a maior quantidade de Eugenol (51%) foi obtida na 1ª colheita com plantas sob stress hídrico e destiladas em fresco enquanto a maior quantidade de Linalool (60%) foi obtida na 2a colheita com plantas micorrizadas (sem stress hídrico) e posteriormente secas. As condições de stress diminuíram a altura e a biomassa das plantas, enquanto as plantas inoculadas apresentaram uma atenuação dos efeitos adversos do stress hídrico. Como tal, a inoculação micorrízica resultou numa melhoria relativamente aos parâmetros de crescimento, bem como nas características fitoquímicas e fisiológicas da menta e manjericão. Em conclusão, os resultados deste estudo poderam ser úteis para se avaliarem novas possibilidades de melhorar a produtividade, o manejo do cultivo e a qualidade da menta e manjericão em países mais quentes e permitindo um menor input de agroquímicos.Nowadays, faced with the reality of climate change and increasing threat of unstable precipitation and temperature increase, it is necessary to find new methods of cultivation of medicinal and aromatic plants (MAP), since the climate has great implications for the plant metabolism. The exploitation of water is particularly important in arid or semi-arid climates such as the Mediterranean. A common consequence associated with the occurrence of water stress is the reduction of the biomass that in the context of the crop production, results in the saving of water but does not compensate the loss of profit. However, in the last decade, the application of arbuscular mycorrhizal fungi (AMF) has been considered an important strategy to counteract the effects of water stress while improving crop yield and quality. In the present study, a factorial experiment based on randomized complete block design with three factors was performed to investigate the effect of AMF and water stress on the essential oil (EO) composition, yield, and physiological and morphological characteristics of mint (Mentha sp.) and basil (Ocimum basilicum L. cv. Genovese Gigante). The factors included AMF inoculation (Glomus intraradices), an irrigation level (mild water stress (60% Field capacity)) and the interaction of both AMF and drought stress. In addition, the effects of plant drying and harvesting at two different stages (winter and late spring) on yield and quality of essential oils were examined. Initially, the seeds were germinated, and the plants transplanted and transferred to a greenhouse, allowing a better control of the environment conditions. During the experiment, different functional characteristics were recorded to obtain information related to the influence of AMF and hydric stress on plant development. After each harvest, the yield of the essential oils was registered and finally the latter were analyzed with the aid of GC and GC-MS. The main EO constituents for mint were Piperitenone oxide (22%–91%) and for basil Eugenol (1%-51%) and Linalool (18%-60%). Overall, the highest amount of Piperitenone oxide (91%) was obtained in the 1st harvest with plants under hydric stress and posteriorly dried and the highest amount of Eugenol (51%) was obtained in the 1st harvest with plants under hydric stress, distillated in fresh. In addition, the highest amount of Linalool (60%) was obtained with mycorrhizal plants (without hydric stress) from the 2nd harvest and posteriorly dried. Drought conditions decreased the height and biomass, whereas AMF plants ameliorated the adverse effect of drought conditions. In general, mycorrhizal inoculation resulted in an improvement in the growth parameters as well as the phytochemical and physiological characteristics of mint and basil. In conclusion, the results of this study might be useful to improve the productivity, cultivation management and quality of mint and basil in warmer countries and with less input of agrochemical
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Ya-Min, Chuang, and 莊雅閔. "The Beauty of Creation—The Works of Oil Painting by Chuang Ya-Min." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/06437908923064343101.
Full textAbstract:
碩士大葉大學
設計暨藝術學院碩士在職專班
97
This research main purpose lies in discusses in the Western drawing art, the realism, impressionism and the abstractionism style's evolution, as well as the oil painting in performance technique, annotates beauty the divine creative force in the creation process the meaning. The present paper subject is “beauty the divine creative force”, namely beautiful scene, kindness the God creation myriad things, the author divides three series according to three stages to conduct the creation research. The author the God words and the life practice takes the creation by the Holy Bible in the springhead, the basis creation scientific theory foundation, and the Western art background research, contains the realism, impressionism and the abstractionism thorough discussion, carries on the drawing creation, simultaneously oneself to US's comprehension and image projection in work. Finally, author by marvelous, change, sumptuous three series, the altogether 30 works share the creation the mood, and hoped that individual will face abstractlyThe artistic creation aspect continues to try hard, to seek the breakthrough, constructs own unique style.
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"Biogeochemical investigation of centrifuged fine tailings deposits at an oil sands mine in Northern Alberta, Canada." Thesis, 2015. http://hdl.handle.net/10388/ETD-2015-09-2334.
Full textAbstract:
Centrifuged fine tailings (CFT) technology was developed to reduce volumes of fluid fine tailings (FFT) stored in tailings ponds at oil sands mines. Increasing FFT inventories in tailings ponds results from slow settlement of clay minerals suspended in oil sands process-affected water (OSPW). High sodium (Na) concentrations in OSPW increase the electrical double layer (EDL) thickness at clay-mineral surfaces, which hinders aggregation and, therefore, settlement. Production of CFT involves dredging FFT from tailings ponds, amending with polyacrylamide and gypsum, and decanter centrifuging. This process promotes aggregation and flocculation, and decreases gravimetric water content from approximately 70 to 55 % (w/w). The resulting CFT is deposited in thin lifts (< 2 m) into sub-aerial containment areas to facilitate further dewatering via freeze-thaw cycling.
This research was focused on characterizing the biogeochemical conditions and processes within the CFT deposits. These deposits remain tension-saturated and, similar to tailings ponds, anaerobic redox processes including iron (Fe) reduction, sulfate (SO4) reduction, and methanogenesis likely dominate.
The geochemistry, mineralogy, and microbiology of core samples from two field-scale test deposits and two full-scale production deposits were examined. Results were compared with previously published data from FFT deposits to assess impacts of chemical amendments on biogeochemical processes within CFT deposits.
Pore-water chemistry within the CFT deposits is affected by evaporative concentration of dissolved ions, which leads to high concentrations of salts (Na, 3000 mg L-1; Cl, 1500 mg L-1; SO4, 5000 mg L-1) and naphthenic acids (NAs 150 mg L-1) near the surface (< 0.3 m) of these deposits. Increases in concentrations of conservative ions (i.e., Cl) indicated that 30 to 40 % of pore water was lost to evaporation at a depth of 0.1 m below surface. Results also suggest that microbially-mediated Fe reduction, SO4 reduction, and methanogenesis are dominant redox processes within the CFT deposits. Microbes related to genera known to use these terminal electron acceptors were identified by high-throughput DNA sequencing data. Increases in dissolved Fe and H2S with depth were also indicative of Fe and SO4 reduction, respectively. These results provide the first insight into biogeochemical conditions and processes within oil sands CFT deposits.
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(9807671), Gregory Jensen. "On-line oil condition monitoring of mobile coal hauling units in establishing improved maintenance practices." Thesis, 2011. https://figshare.com/articles/thesis/On-line_oil_condition_monitoring_of_mobile_coal_hauling_units_in_establishing_improved_maintenance_practices/13457117.
Full textAbstract:
"The research presented represents the culmination of four years of on-site research at BMA Peak Downs Mine located south-west of Mackay in Central Queensland. The primary focus of this research was to improve oil cleanliness and filter life through the installation of Pall Corporation Stress Resistant Technology (SRT) filters across the steering, hydraulic, transmission and differential oil circuits on a Caterpillar (CAT) 784C coal hauling unit"--P. 2.