Mould is a common contamination in cereals. The growth of mould can stimulate mycotoxins production andsome of which at critical concentrations cause health problems in humans and animals. Fusarium is one of thefungus species that has been found in crops and can cause major problems for farmers such as reduced harvestand economic losses. A group of Fusarium species, Fusarium avenaceum, Fusarium poae and Fusariumtricinctum express a mycotoxin, enniatin. The limited information available today about enniatin-forming fungiis that they grow out on fields of wheat in colder climates. This project aims at developing methods for detection,quantification and identification of known and unknown fungi present in Swedish cereals during 2009-2011. Theproject was carried out using two previously published methods, TMAV and MGB, which both use TaqManprobes with realtime-PCR detection. The methods were evaluated for robustness, efficiency, accuracy, inclusionand exclusion. The results showed that both methods, TMAV and MGB, could be used to detect Fusariumavenaceum. The results for the TMAV method were that it could be used with custom annealing temperatureand chemical concentrations for the best detection. The MGB method can be used to detect Fusarium avenaceumwith Fusarium tricinctum in the same analysis. Both methods can be included in future mapping projects when itis of interest to quantify enniatin producing moulds.

<I>Phytophthora cinnamomi </I>var. <I>cinnamomi, Pythium ultimum </I>var. <I>ultimum </I>and <I>Pythium undulatum </I>were successfully isolated from naturally regenerating <I>Pinus sylvestris </I>forests across north Scotland. Molecular and morphological characterisation enabled accurate identification of these Oomycetes to the variety level. <I>In vitro</I> and glasshouse pathogenicity trials demonstrated that under artificial temperature, light and water regimes the Oomycetes had the potential to reduce plant growth and cause chlorosis of the <I>P. sylvestris</I> foliage after two months. Soil pH was also determined as having a significant effect on <I>P. sylvestris </I>growth in terms of foliage colour and dry mass. Biological control <I>in vitro </I>experiments with <I>Bacillus subtilis</I> and <I>Pseudomonas fluorescens</I> produced significant inhibition of Oomycete growth but on transfer to the glasshouse trials, antagonism was not observed. This study was undertaken to establish the presence of fine root pathogens, namely those belonging to the Oomycetes, within regenerating <I>Pinus sylvestris</I> forests in northern Scotland. The identify of the pathogens was determined using morphological and molecular biology techniques. The virulence of the fine root pathogens on <I>Pinus sylvestris </I>seedlings (1 + 0) was then determined by a series of <I>in vitro</I> and glasshouse trials. Interactions between soil pH and bacterial biological control agents were also tested against each of the pathogens. Pathogen trials were undertaken to show the potential effect of the Oomycetes on <I>Pinus sylvestris </I>seedlings. The glass house trial was scored on foliage colour and dry weight of seedlings 18 months of age, grown in pH amended Irish moss peat. In comparison to the control, inoculation with <I>P. cinnamomi</I> caused a significantly greater frequency of chlorotic/dead seedlings. In contrast, inoculation with <I>P. undulatum </I>(syn. <I>P. dimorphum</I>) resulted in a greater number of healthy seedlings than the control. No significant difference in the proportion of healthy and chlorotic/dead seedlings was found between the bio-control bacteria groups. pH was found to have a significant effect on seedling growth. At pH 7, compared to pH 3, there was a significant greater likelihood of the seedlings being chlorotic/dead.

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Understanding how respiratory health risks are associated with poor housing is essential to designing effective strategies to improve children’s quality of life. The objective of this thesis is to determine the relationship between the respiratory health of children and the condition of the homes in which they reside – using both building science and health data. The thesis therefore, examines the association between self-reported mould in the home, housing conditions, and the respiratory health of children. The study contributes to both the medical and engineering research community by enabling researches, designers, and Building Code officials to focus on cost-effective target areas for improving indoor air quality and thus, the respiratory health of children. A survey designed to assess the relationship between respiratory health and housing conditions was completed by 3,424 parents of grades 3 and 4 children in Winnipeg, Manitoba, Canada. Air samples were then taken in the homes of a subset of 715 houses– one in the child’s bedroom and another in the basement – with an exterior neighborhood air sample as a control measure. Engineering audits on 715 homes were then conducted – including measurements of relative humidity, temperature, and moisture content of walls. Major findings include the following: (1) Self-reported visible mould in the home is clearly associated with the presence of air-borne mould. (2) There are fewer healthy children when mould is present in the home. (3) Cladosporium levels (CFU/m3) in the house were associated with children’s asthma in combination with persistent colds. (4) Measures taken by homeowners to increase the air-tightness of their homes, such as new windows increased the likelihood of having higher air-borne moisture and mould levels. (5) The “hygiene hypothesis” was supported, which postulates that denying children access to certain types and levels of biological contamination at a young immune-developmental age, increases their susceptibility to allergic responses at a later age.

It is known that a newly formed glass container will only possess a very small fraction of its theoretical strength. This suggests that damage occurs on the surface of the glass melt during the forming process due to glass to mould contact and hot glass handling. It might be expected that any damage inflicted on the surface of a glass article during manufacture would heal at the elevated manufacturing temperatures used, however this does not appear to be true. Therefore, the actual mechanism by which glass strength is reduced during forming needs to be fully understood and the work presented in this thesis addresses this problem. Experiments, therefore, have been carried out here which simulate the formation of glass articles using an experimental pressing rig by systematically altering processing parameters such as the mould material, surface fmish of the mould, pressing temperature and atmosphere. Processing parameters that are used industrially for the formation of glass containers were generally reproduced wherever possible in order to investigate the glass-to-mould interaction. The interaction of both a cast iron mould material and carbon-carbon composite materials with a soda-lime-silica glass were examined using the techniques of scanning electron microscopy, x-ray photoelectron spectroscopy and atomic force microscopy in order to determine the type and extent of surface damage formed. The surfaces of the pressed glass samples made were found to contain defects of embedded particles and indented dimples. The embedded particles found were usually due to bulk material transfer from the plunger material used. The texture found on the surface of the pressed glass samples was found to be directly affected by the surface fmish of the plunger. Pressing glass samples using a cast iron plunger at an initial plunger temperature below 450°C resulted in a randomly rippled 'chilled' surface. As the initial temperature of the plunger was increased, the surface texture of the pressed glass became a closer replica of the plunger surface. The use of vacuum assistance to form the glass samples also resulted in the surface of the pressed glass becoming a closer replica of the original plunger surface, even at lower pressing temperatures. The surfaces of the cast iron and carbon-carbon composite plungers appeared to have been affected by the initial plunger temperatures used. As the initial pressing temperature was increased, the amount of oxidation for both material types increased. In the case of the carbon-carbon composite materials investigated, both the matrix and fibres were found to have broken down at the pressing temperatures used. X-ray photoelectron spectroscopy, of the pressed glass surfaces and the plunger materials indicated that sodium ions had migrated from the glass melt to the plunger surface during forming.

No / Eleven species of fungi and one slime-mould are added to the previous list of fungi from Indian Ocean islands made by the authors in 2004. Two other species in the area are confirmed. Our knowledge of fungal distributions in these remote islands is extended and comments are made on some immature collections. This small collection does, however, indicate a palaeotropical element to the mycota with bias towards species found in Southeast Asia, although some have a worldwide distribution.

The diploma thesis presents a production technology design of an automotive industry component – a resonator holder. The initial production run of the part is 500 000 pcs. Injection production has been selected based on variant analysis of available technologies. Technological calculations have been performed. The selected material PP 56M10 will be used for operation in granules. A quadruple shaped cavity injection mold with a tunnel gate has been designed. Based on estimated technological properties an Arburg Allrounder 470 A machine has been selected. The break-even point (BEP) shows economic return at the production of 185 595 pcs.

Due to the high efficiency and productivity of continuous casting process, this method has been the most employed process to produce steel in past decades. The need to improve and optimize the finished product made it essential to gain more knowledge about the process, types of defects that may occur and the reasons for them. Moreover, the solutions for reducing the shortcomings in continuous casting process have been an intriguing subject to study. Many attempts have been done in order to reach this goal. Understanding, determining and optimizing the mould flux slag properties is especially important, since it plays an important and significant role in this process. For this, it is of outmost importance to acquire more knowledge about different properties of mould flux powders. Hence, there has been a world wide effort to measure and model the properties of mould flux properties, such as liquidus and solidus temperatures, heat capacity, enthalpy, thermal expansion, density, viscosity, electrical conductivity, surface tension and thermal conductivity. This thesis presents a brief review on continuous casting process, mould flux powder and its properties and characteristics. Furthermore, it focuses on the thermo-physical properties of mould fluxes. In present work, different industrial mould flux powders have been analyzed to measure their viscosity, break temperature, physical properties such as density, flowablity of powder, slag structure and chemical composition. The experimental data have been compared to some of the most commonly used models such as Riboud model, Urbain model, Iida model and KTH model.

The purpose of this study was to develop a composite manufacturing process that would be able to deliver Class A surface finished products in the context of mould manufacturing methods. The problem required solving was to overcome the time needed to prepare Class A surfaces, by developing a composite manufacturing process that will deliver Class A surface finished products straight from the mould. The process was aimed at the entire development process, from mould and plug design up to the finished product. A literature study and a factory mould survey were conducted with a view to obtain the necessary insights into surface finishing and composite manufacturing. These surveys were followed by seven constructional tests which determined the most appropriate solutions for the proposed manufacturing processes. Test 1 was used to determine a quality finish standard for composites from the sanding grits used to finished composite surfaces versus surface roughness values used in other industries. The standard determined that a P800 finish has a roughness between 0.200 and 0.150 um and constitutes a Class A3 finish. P1000 to P1200 have a roughness between 0.150 um to 0.100 um and constitutes a Class A2 finish. Finally a P2000 and higher have a roughness of 0.100 um and lower and constitutes Class A1 surface finish. After the standard was set, the tests for finishing of the moulds, plugs and parts commenced. Test 2 was conducted on the CNC manufacturing of plugs out of Nuceron651 tooling board. Tool path parameters were varied in a matrix. The samples with the best surface finish value were cut with a step-over of 0.5 and feed of 800 mm/min. These parameters were found to be the most influential. Test 2 and 4 revealed that the plug surface finishing should commence with conventional 2K paint finishing, with a possibility of acrylic split surface. This process produced projected mould surfaces between 0.150 um and 0.200 um, which can be categorised as Class A-3. Test 5 and 6 determined methods for improving the mould surface quality and durability. It was established that the tooling gelcoat should be applied whilst being heated and backed with at least two layers of glass veil and a steady increase of GSM of structural glass fibres to prevent print-through. Test 3 determined that the mould corners could be strengthened with rovings pressed into the corner. It was also established that the moulds surfaces will require finishing after demoulding. The final moulds were manufactured from a fibreglass composite structure with tooling gelcoat surface. A number of guidelines and a set process were developed in order to produce moulds with a surface finish of average 0.9 um, equivalent to Class A1. Release agents were tested in Test 7, and the Loctite Frekote 770-NC release system was deemed appropriate for use with In Mould Coating (IMC) of 2K Paint. These elements were all synthesised into plug, mould and part manufacturing processes. The proposed processes were validated by the manufacturing of a JS instrument panel, which delivered a Class A2, 0.175 um, finish with IMC of 2K paint. With only a minor sanding of P3000 grit and polishing, the part was made into a Class A1 surface, measured at 0.63 um. The study proved that it is possible to produce Class A finished part with IMC. This method can provide a solution aimed at the elimination of P600 and lower finishing of composite parts manufactured with IMC. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014

The purpose of this study was to develop a composite manufacturing process that would be able to deliver Class A surface finished products in the context of mould manufacturing methods. The problem required solving was to overcome the time needed to prepare Class A surfaces, by developing a composite manufacturing process that will deliver Class A surface finished products straight from the mould. The process was aimed at the entire development process, from mould and plug design up to the finished product. A literature study and a factory mould survey were conducted with a view to obtain the necessary insights into surface finishing and composite manufacturing. These surveys were followed by seven constructional tests which determined the most appropriate solutions for the proposed manufacturing processes. Test 1 was used to determine a quality finish standard for composites from the sanding grits used to finished composite surfaces versus surface roughness values used in other industries. The standard determined that a P800 finish has a roughness between 0.200 and 0.150 um and constitutes a Class A3 finish. P1000 to P1200 have a roughness between 0.150 um to 0.100 um and constitutes a Class A2 finish. Finally a P2000 and higher have a roughness of 0.100 um and lower and constitutes Class A1 surface finish. After the standard was set, the tests for finishing of the moulds, plugs and parts commenced. Test 2 was conducted on the CNC manufacturing of plugs out of Nuceron651 tooling board. Tool path parameters were varied in a matrix. The samples with the best surface finish value were cut with a step-over of 0.5 and feed of 800 mm/min. These parameters were found to be the most influential. Test 2 and 4 revealed that the plug surface finishing should commence with conventional 2K paint finishing, with a possibility of acrylic split surface. This process produced projected mould surfaces between 0.150 um and 0.200 um, which can be categorised as Class A-3. Test 5 and 6 determined methods for improving the mould surface quality and durability. It was established that the tooling gelcoat should be applied whilst being heated and backed with at least two layers of glass veil and a steady increase of GSM of structural glass fibres to prevent print-through. Test 3 determined that the mould corners could be strengthened with rovings pressed into the corner. It was also established that the moulds surfaces will require finishing after demoulding. The final moulds were manufactured from a fibreglass composite structure with tooling gelcoat surface. A number of guidelines and a set process were developed in order to produce moulds with a surface finish of average 0.9 um, equivalent to Class A1. Release agents were tested in Test 7, and the Loctite Frekote 770-NC release system was deemed appropriate for use with In Mould Coating (IMC) of 2K Paint. These elements were all synthesised into plug, mould and part manufacturing processes. The proposed processes were validated by the manufacturing of a JS instrument panel, which delivered a Class A2, 0.175 um, finish with IMC of 2K paint. With only a minor sanding of P3000 grit and polishing, the part was made into a Class A1 surface, measured at 0.63 um. The study proved that it is possible to produce Class A finished part with IMC. This method can provide a solution aimed at the elimination of P600 and lower finishing of composite parts manufactured with IMC. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014