Control of seed-associated micro-organisms is vital in reducing losses of plants of economic importance. Recalcitrant seeds being metabolically active and able to be stored only under conditions of high relative humidity makes it more difficult to control contaminants. Nevertheless, means need to be developed to eliminate, or at least curtail, seed-associated fungi and bacteria. The use of biological control is a highly recommended alternative to chemical control for reducing the risk of killing beneficial organisms, as well as in terms of health and environmental hazards. Furthermore, when working with seed-derived tissues, it is extremely important to optimise a method or methods to control contamination without compromising the viability or further development of the explants. The original aim of the present study was to determine whether the biocontrol agents, EcoT® and Eco77® (commercial products of the spores of Trichoderma harzianum) would effectively control/eliminate micro-organisms from the embryonic axes of Trichilia dregeana, while promoting growth under in vitro conditions. Other means were also tested for their efficacy in controlling contaminants; these were application of Benlate®, Nipastat® (a mixture of parabens), anodic water (the anodic fraction of an electrolysed dilute solution of calcium and magnesium chloride), sodium dichloro-isocyanurate (Medi-Chlor®[NaDCC]) and alginate gel encapsulation of the embryonic axes. Prior to the experiments, fungal contaminants from the embryonic axes were isolated on potato dextrose medium and identified using light microscopy. EcoT and Eco77 were initially individually tested by co-culture as conidial suspensions with the embryonic axes. A further approach used liquid culture (potato dextrose broth) as well as solid culture medium (based on sugarcane bagasse) in/on which the strains of Trichoderma harzianum had been grown. This was aimed at testing for the possible presence of compounds released by T. harzianum into the media, which might prove to be effective in curtailing/eliminating the axis-associated microflora. Among the different treatments tested, the best method was utilised to decontaminate the embryonic axes prior to minimal-growth storage (hydrated axes encapsulated in alginate gel ‘beads’). Penicillium spp. were predominant among the different fungi isolated, which included Fusarium spp., Rhizopus spp., Aspergillus niger and Aspergillus flavus. Co-culturing with T. harzianum for 24 h was successful in terms of the survival of the embryonic axes, although the roots produced were shorter than when axes were cultured alone, but had no effect in eliminating the contaminants. Longer periods of co-culturing with T. harzianum affected the germination of the embryonic axes of T. dregeana compared with axes germinated in the absence of the biocontrol agent (control). The culture filtrate negatively affected germination of the T. dregeana embryonic axes, although it was effective against the associated contaminants. Nipastat was effective in reducing the contamination, and, depending on the concentration, did not affect germination adversely. Medi-Chlor was highly effective in eliminating all the contaminants from axes in vitro. Both these treatments were therefore used to decontaminate axes before minimal-growth storage. All the NaDCC-treated, encapsulated axes examined after 14 d hydrated storage [in Magenta boxes] and after 14-42 d in polythene bags survived; however the axes stored in aluminium foil-lined bags and Eppendorf tubes soon lost viability. The recommendation is therefore made that the decontamination treatment based on use of NaDCC (or other preparations of sodium dichloro-isocyanurate) be tested on embryonic axes of a range of recalcitrant-seeded species, and, if successful, the procedure be introduced into cryopreservation protocols. The use of NaDCC has emerged as a promising method of eliminating contaminating microflora which otherwise compromise in vitro procedures, from seed-derived explants. Furthermore, containment of decontaminated encapsulated axes in sealed polythene bags offers an apparently ideal means of temporary storage and dissemination. The results should find considerable applicability when excised embryonic axes representing the germplasm of recalcitrant seeds, are cryoconserved. / Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2013.

For industrial processes high availability and efficiency are important goals in plant operation. This thesis presents studies and development of tools for on-line treatment of process deterioration and model and sensor errors in order to achieve these goals. Deterioration of measurement devices, process components and process models has caused economical losses, plant failure and human losses. The development of on-line methods to prevent such losses is of special interest and has been conducted at The Department of Energy Technology, Mälardalen University. Important technological obstacles to implementing automatic on-line methods have been identified, such as data selection for adaptation and adaptation of data-driven models to new states. A new method has been developed for decision support by combining artificial intelligence methods and heat and mass balance models, and concepts are proposed for decision support in order to detect developing faults and to conduct appropriate maintenance actions. The methods have been implemented in simulation environment and evaluated on real process data when available. The results can be sumarised as successful development of a decision support method on a steam turbine by combining artificial neural networks and Bayesian networks, and identification of important obstacles for automation of methods for adaptation of heat and mass balance process models and data-driven models when they are subject to deterioration.

Pavement Management Systems (PMS) are widely used by transportation agencies to maintain safe, durable and economic road networks. PMS prioritize the maintenance and rehabilitation of pavement sections by evaluating pavement performance at the network level. There are many PMS software packages that have been developed over the past decades for provincial/state road agencies. However, sometimes due to lack of budget and experience, adopting the existing PMS for a road agency is not cost effective. Thus, it is important to introduce a simple, effective, and affordable PMS for a local agency and municipality. This research is carried out in partnership between the City of Markham and the Centre for Pavement and Transportation Technology (CPATT) located at the University of Waterloo. For the purpose of developing a PMS for local agencies, an extensive literature review on PMS components was carried out, with emphasizing data inventory, data collection, and performance evaluation. In addition, the literature review also concentrated on the overall pavement condition assessment. In July 2011, a study on “Evaluation of Pavement Distress Measurement Survey” was conducted as a part of this research and was distributed to cities and municipalities across Canada. The study focused on the current state-of-the-practice in pavement distress and condition evaluation methods used by local agencies to compare the results from the literature review. The components of the proposed PMS framework are also developed based on the literature review with some modifications and technical requirements. The City of Markham is selected as a case study, since it represents a local agency and provides all the data, to illustrate the validation of the proposed PMS framework.

This research explored the processing and properties of PNCs using a polyfurfural alcohol (PFA) matrix. The precursor for PFA, furfuryl alcohol (FA) is sourced from feedstocks rich in hemicellulose, such as corn cobs, oat hulls and wood. To exploit FA as a polymerizable solvent, cellulose whiskers (CW) and montmorillonite clay (MMT) were used as the nanoparticle phase. Results from PNC processing show that CW and MMT can be dispersed in the PFA matrix by means of insitu polymerization, without the use of surfactants or dilution in solvents. Both CW and MMT nanoparticles catalyze the polymerization of furfuryl alcohol (FA). Moreover, the insitu intercalative polymerization of FA in the interlayer galleries of MMT leads to the complete exfoliation of the MMT in the PFA matrix. CW and MMT both function as effective matrix modifiers, increasing the thermal stability of PFA nanocomposites compared to pure PFA polymer. The increased thermal stability is seen as significant increases in the onset of degradation and in residual weight at high temperature. This research also explored the surface functionalization of Cu, Ni and Pt substrates by self-assembly of a range of difunctional linker molecules. Characterization by XPS and PM-IRRAS indicate that diisocyanides and dicarboxylic acids both form chemically "sticky" surfaces after self-assembly on Cu and Ni. Sticky surfaces may provide a means of increasing nanoparticle dispersion in metal nanocluster filled PNCs, by increasing their interaction with the matrix polymer. Another potential application for sticky surfaces on Cu is in the ongoing miniaturization of circuit boards. The functionalization of Cu bond pad substrates with linker molecules may provide an alternate means of bonding components to their bond pads, with higher placement accuracy compared to solder bumps.

In a globalizing world, trade has become essential to supporting the needs and wants of billions of people. Virtually everyone now consumes resource commodities and manufactured products traded all over the world; the ecological footprints of nations are now scattered across the globe. The spatial separation of material production (resource exploitation) from consumption eliminates negative feedbacks from supporting eco-systems. Most consumers remain unaware of the impacts that their trade dependence imposes on distant ecosystems (out of sight out of mind). I take the first steps in developing a conceptual and practical framework for an ‘interregional ecology’ approach to exploring and analyzing sustainability in an increasingly interconnected world. Such an approach accounts for some of the ‘externalities’ of globalization and international trade. It underscores the increasing dependence and impact of almost any country on resources originating from others and recognizes that the sustainability of any specified region may be increasingly linked to the ecological sustainability of distant supporting regions. I empirically describe and quantify some of the interregional material linkages between selected countries. I document the flows of renewable resources into the U.S. and quantify the U.S. external material footprint (EF) on specific countries. I then document the physical inputs involved in production of most agricultural export products from Costa Rica and Canada. Finally, I focus on major export products such as bananas, coffee and beef in Costa Rica and agricultural activities in the Canadian Prairies and document some of the ecological consequences (loss of habitat, soil degradation, water contamination and biodiversity loss) of that production. My research findings show increasing U.S. imports, increasing reliance on external sources and growing external ecological footprints. They also show how production activities mostly for overseas consumption led to changes in ecological structure and function in the studied export countries. This dissertation adds a missing trans-national dimension to the sustainability debate effectively integrating the policy and planning domain for sustainability in one region with that in others. While my research focuses mainly on documenting the nature and magnitude of interregional connections I also consider some of the implications of the interregional approach for sustainability planning.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 4 uppsatser.

Vertical up-flow of supercritical fluid in the subchannel of a heated rod bundle was numerically simulated using the Computational Fluid Dynamics (CFD) codes ANSYS CFX and ANSYS FLUENT. A total of seven cases from three different sets of experiments were simulated. Three-dimensional steady-state predictions of fluid velocity, pressure, and temperature were made using five versions of two-equation RANS turbulence models with accompanying wall treatments. In addition, the temperature distribution in a solid region comprising a heater and sheathing was also computed in some cases. The k-epsilon turbulence model, implemented using CFX and scalable wall functions, provided the numerical results that have the smallest overall deviation from experimental results for three of the seven cases, and predicts the experimental data of the remaining four cases reasonably well, unlike other turbulence models that severely over-predict the experimental data for wall surface temperature. / February 2016

Thesis (MSc )--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: Washing and cleansing in an aqueous washing solution is a complex process involving the interaction of numerous physical and chemical processes. Investigations indicate that various factors present during repeated laundering might have an adverse effect on textile fabrics. Little is known, however, about the effect of the different mechanical wash actions on the deterioration of textiles. The automatic washing machines commonly used in South African households are often broadly classified as top loaders and front loaders. On closer inspection, however, it becomes clear that marked differences exist between the horizontal drum machines (H), vertical drum agitator type (V(A)) and vertical drum impeller type machines (V(/)). The effect of laundering on the wear life of textile fabrics has been extensively investigated, but a serious need for research on the effect of the different mechanical washing actions of the different washing machines on textile fabrics exists on both national and international level. A number of factors have an effect on textile deterioration during washing, e.g. number of washes, temperature of wash liquid, detergent type as well as fabric finishes and water quality. Fabric properties like changes in tensile strength, print deterioration and fraying, as well as electron microscope photographs, were used as indicators of mechanical deterioration to textiles. The broad aim of this exploratory study was firstly, to compare the effect of repeated washing in different domestic automatic washing machines (commonly used in South Africa) on the possible mechanical damage to textile fabrics and, secondly, to compare the soil removal efficiency of the mechanical wash actions of the different machines. An experimental study was therefore decided on. The washing of the test fabrics, as well as the testing, was carried out under controlled conditions in a laboratory. Apart from the different mechanical wash actions of the individual machines, the effect of the variables wash temperature, level of detergent and number of washes, was also investigated. This was done by measuring tensile strength, print deterioration and fraying propensity on samples laundered repeatedly at 40°C or 60°C, with and without detergent in the washing liquid, and comparing the colour change measured on laboratory-soiled test fabrics after washing. Analysis of the mechanical wash actions of the seven washing machines compared in this study indicated conspicuous differences among machines. It can be concluded that the mechanical wash action in the category V(A) machines is the most severe, and causes the highest reduction in tensile strength, the greatest print deterioration and the highest degree of fraying. These machines did not, however, exhibit greater soil removal efficiency than the other two categories of washing machines. The machines from category H did not exhibit a significantly different soil removal efficiency than those from category V(A), but their mechanical wash action proved to be less severe. Category V(/) machines seem to have the most delicate wash action and will probably cause the slightest fabric deterioration over the long term, but unfortunately produces poor soil removal efficiency results. This study also confirmed that washing fabrics in water alone causes more deterioration of tensile strength in fabrics than washing with detergent in the wash solution. Due to the limited scope and exploratory nature of this research/study, certain aspects of automatic washing machine processes could not be tested empirically. Recommendations for future research and implications for consumers were formulated. / AFRIKAANSE OPSOMMING: Was en skoonmaak in 'n waterige oplossing is 'n komplekse proses wat 'n interaksie tussen verskeie fisiese en chemiese prosesse behels. Ondersoeke dui aan dat verskeie van die faktore teenwoordig tydens herhaalde wasprosesse 'n nadelige effek op tekstielstowwe mag he. Baie min is egter bekend oor die effek van die verskillende meganiese wasaksies op die degenerasie van tekstiele. Die outomatiese wasmasjiene wat algemeen in Suid-Afrikaanse huishoudings gebruik word, word dikwels breedweg geklassifiseer as bolaaiers en voorlaaiers. By nadere ondersoek word dit egter duidelik dat daar opvallende verskille bestaan tussen die horisontale drom masjiene (H), die vertikale drom roerder tipe ((V)A)) en die vertikale drom stuwer tipe (V(/)) masjiene. Die effek van was op die draleeftyd van tekstielstowwe is uitvoerig ondersoek, maar daar bestaan op beide nasionale en internasionale vlak In ernstige behoefte aan navorsing oor die effek van die verskillende meganiese wasaksies van die verskillende wasmasjiene op tekstielstowwe. Faktore 5005 die aantal wasse, temperatuur van die wasoplossing, detergent tipe, water kwaliteit en tekstielstoftipe en -afwerking(s) het In effek of tekstieldegenerasie gedurende was. Tekstielstofeienskappe 5005 veranderinge in die breeksterkte van die tekstielstof of die tekstielstofmassa per eenheidsarea, agteruitgang van bedrukking, rafeling, sowel as elektronmikroskoop foto's word as aanduiding van meganiese degenerasie t.o.v. tekstiele beskou. Die oorkoepelende doe I van hierdie eksploratiewe studie was eerstens, om die effek te vergelyk van herhaalde was in verskillende outomatiese wasmasjiene (algemeen in gebruik in Suid-Afrika) op die moontlike meganiese beskadiging aan tekstielstowwe, en tweedens, om die doeltreffendheid van vuilverwydering op die wasaksies van die verskillende masjiene te vergelyk. Daar is gevolglik op In eksperimentele studie besluit. Die was van die tekstielstowwe, sowel as die laboratoriumtoetse, is onder gekontroleerde atmosferiese toestande in In laboratorium uitgevoer. Afgesien van die verskillende meganiese wasaksies van die individuele masjiene, is die effek van die veranderlikes westemperetuur, detergentv!ak en aanta! wasse ook ondersoek. Dit is gedoen deur die bepaling van breeksterkte en die meting van die mate van agteruitgang van bedrukking en mate van geneigdheid tot rafeling van kledingstowwe na herhaalde was by 40°C en 60°C, met en sonder detergent in die wasvloeistof. Die kleurverandering na was is ook gemeet op laboratorium gevlekte monsters. Die analise van die meganiese wasaksie van die sewe wasmasjiene wat in hierdie studie vergelyk is, het opvallende verskille tussen masjiene uitgewys. Daar kan tot die gevolgtrekking gekom word dat die meganiese wasaksie in kategorie V(A) masjiene die ergste is, wat gevolglik die grootste verlaging in breeksterkte en die meeste afieruitgang van bedrukking en rafeling veroorsaak het. Hierdie masjiene het egter nie meer doeltreffende vuilverwydering tot gevolg gehad in vergelyking met die ander kategoriee van wasmasjiene nie. Die masjiene in kategorie H het nie 'n betekenisvolle verskil in doeltreffenheid van vuilverwydering van die van kategorie V(A) getoon nie, maar die meganiese wasaksie was minder straf. Kategorie V(/) masjiene het blykbaar die mees delikate wasaksie en sal moontlik die minste tekstielstof degenerasie oor die langtermyn toon, maar ongelukkig is die resultate t.o. v. die doeltreffendheid van vuilverwydering swak. Die studie bevestig dat die was van tekstielstowwe in water aileen 'n groter verlaging in breeksterkte van tekstielstowwe veroorsaak as wat die geval is wanneer met 'n detergent in die wasvloeistof gewas word. Weens die beperkte omvang en eksploratiewe aard van die studie kon sekere aspekte van die outomatiese wasprosesse nie empiries getoets word nie. Aanbevelings vir toekomstige navorsing en implikasies vir verbruikers is geformuleer.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The wood over time passes through a process natural what that gradually losing their (mechanical, physical or chemical) properties in a gradual state of decay. This fact is compounded by the action of wood-destroying organisms that under favorable weather conditions such as rain, wind, damage with the quality of the wood. The present study aimed to evaluate the natural durability of wood Tetrorchidium rubrivenium Poeppig & Endlicher (Canemaçu) under the action of deteriorative organisms in field tests and laboratory analyzing two regions of wood, peripheral region and central region. The wood used for this work were obtained from five trees Canemaçu. We analyzed the apparent specific gravity for the two regions studied wood. For the laboratory test was followed to ASTM D 2017 (ASTM , 2005) with modification in the specimens to 2.0 x 2.0 x 0.9 cm , which were sawn parts of the peripheral region and the central region of same samples prepared for testing field with dimensions of 2.0 x 2.0 x 30 . Were analyzed for laboratory testing and field: mass loss and colorimetry and the field test: index behavior, static bending (MOR and MOE) and solubility in sodium hydroxide. For mass density at 12% moisture was obtained for peripheral region 0.483 g / cm ³ and central 0.424 g / cm ³ , which statistically significantly. The loss of mass in the laboratory test for brown rot was similar in the two regions with an average of 33 %, while for white rot results are different, with the peripheral region 23.35% and 36.57 % central region. The colorimetric parameters L *, a * and b * were significantly different depending on the fungal attack of brown rot and white rot in laboratory test values. In field trial samples installed in the open field showed a trend towards higher mass losses for samples of the forest. The deterioration index was reduced with the passage of time of exposure to the environment. The MOE and MOR were being reduced over time, but with periods of oscillation. The values obtained in solubility in 1% sodium hydroxide solution been declining with increasing time of exposure in the field. All wood samples exposed to natural weathering demonstrated a reduction in the b * parameter, causing the browning of the samples. Comparing the results obtained in laboratory tests and field for both regions analyzed the wood, it is concluded that both conditions do not have to be exposed in contact with the ground. / A madeira passa ao longo do tempo por um processo em que acontece aos poucos a perda de suas propriedades (mecânicas, físicas ou químicas) em um gradativo estado de apodrecimento. Este fato é potencializado pela ação de organismos xilófagos que em condições favoráveis de intempéries, como chuvas, ventos, entre outros corrompem com a qualidade da madeira. A presente pesquisa teve por objetivo avaliar a durabilidade natural da madeira de Tetrorchidium rubrivenium Poeppig & Endlicher (Canemaçu) sob a ação de organismos biodeterioradores, em ensaios de campo e de laboratório, analisando duas regiões da madeira, região próxima a casca e região próxima a medula. A madeira utilizada para a realização deste trabalho foi obtida de cinco árvores de Canemaçu. Foi analisada a massa especifica aparente para as duas regiões da madeira estudadas. Para o ensaio em laboratório foi seguido à norma ASTM D 2017 (ASTM, 2005) com modificação nos corpos de prova para 2,0 x 2,0 x 0,9 cm, onde foram serrados de peças da região próxima a casca e da região próximo a medula das mesmas amostras confeccionadas para ensaio de campo com dimensões de 2,0 x 2,0 x 30 cm. Foram analisados para ensaios de laboratório e campo: perda de massa e colorimetria, e para o ensaio de campo: indicie de comportamento, flexão estática (MOE e MOR) e solubilidade em hidróxido de sódio. Para a massa específica aparente a 12% de umidade obteve-se para região próxima a casca 0,483g/cm³ e região próxima a medula 0,424g/cm³, onde apresentou diferença estatística. A perda de massa sofrida em ensaio de laboratório para a podridão parda foi parecida nas duas regiões com uma média de 33%, já para podridão branca os resultados foram distintos, com na região próxima a casca 23,35 % e região próximo a medula 36,57%. Os parâmetros colorimétricos L*, a* e b* apresentaram valores significativamente distintos em função do ataque dos fungos de podridão parda e podridão branca em ensaio de laboratório. Em ensaio de campo as amostras instaladas no campo aberto apresentaram a tendência de maiores perdas de massa em relação às amostras da floresta. O Índice de deterioração foi reduzindo-se com o decorrer do tempo de exposição ao ambiente. O MOE e o MOR foram sendo reduzidos com o passar do tempo, porém com períodos de oscilação. Para os valores obtidos na solubilidade em hidróxido de sódio 1% observou-se que foram decaindo conforme aumenta o tempo em exposição a campo de apodrecimento. Todas as amostras de madeira expostas ao desgaste natural demostraram uma redução do parâmetro b*, ocasionando o escurecimento das amostras. Comparando-se os resultados obtidos nos testes de laboratório e de campo para ambas as regiões da madeira analisadas, conclui-se que ambas não apresentam condições de serem expostas em contato com o solo.

Across a large part of the UK highways network the carriageway and pavement foundations are drained by Highway Filter Drains (HFDs). A HFD is a linear trench constructed either at the pavement edge or central reserve, fitted with a porous carrier pipe at the base and backfilled with an initially highly porous aggregate material. This arrangement enables the swift removal of surface runoff and subsurface water from the pavement system minimising road user hazards and eliminating risk of structural damage to the pavement sub-base. The highly porous backfill filters throughout its operational life fines washed from the pavement wearing course or adjacent land. HFDs have been found to be prone to collecting near the basal sections (pipe) or surface layers contaminants or detritus that causes the filter media to gradually block. The process has been defined as HFD clogging and it has been found to lead to reduced drainage capacity and potentially severe drop of serviceability. O&M contractual agreements for DBFO projects usually propose in-service and handback requirements for all assets included in the concession portfolio. Different performance thresholds are thus prescribed for pavements, structures, ancillary assets or street lighting. Similar definitions can be retrieved for drainage assets in such agreements, and these include HFDs. Performance metrics are defined though in a generic language and residual life (a key indicator for major assets that usually drives long-term maintenance planning) is prescribed without indicative means to evaluate such a parameter. Most of pavement maintenance is carried out nowadays using proactive management thinking and engineered assessment of benefits and costs of alternative strategies (what-if scenarios). Such a proactive regime is founded upon data driven processes and asset specific ageing / renewal understanding. Within the spectrum of road management, maintenance Life Cycle Costs are usually generated and updated on an annual basis using inventory and condition data linked to a Decision Support Tool (DST). This enables the assessment and optimisation of investment requirements and projection of deterioration and of treatment impacts aligned to continuous monitoring of asset performance. Following this paradigm shift in infrastructure management, a similar structured methodology to optimise HFD maintenance planning is desired and is introduced in this thesis. The work presented enables the identification of proactive maintenance drivers and potential routes in applying a systemised HFD appraisal and monitoring system. An evaluation of Asset Management prerequisites is thus discussed linked to an overview of strategic requirements to establish such a proactive approach. The thesis identifies condition assessment protocols and focuses on developing the means to evaluate deteriorated characteristics of in service drains using destructive and non-destructive techniques. A probabilistic HFD ageing / renewal model is also proposed using Markov chains. This builds upon existing deterioration understanding and links back to current treatment options and impacts. A filter drain decision support toolkit is lastly developed to support maintenance planning and strategy generation.