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This thesis presents a novel three dimensional (3D) image-analysis method for characterizing the physical characteristics of coarse particles in the field, and introduces new methodology for the total analysis of glacial till samples. The novel image analysis method, called the GID method, is capable of determining the size, shape and surface texture of each individual clast analysed. Images of particles are taken in the field and analysis is done in the laboratory. Therefore the GID method makes it feasible to analyse statistically representative large sample in short period; for poorly sorted sediments, such as till, one-tonne is required if the analysis includes cobble size. The capability of the GID method was demonstrated by studying coarse clasts (20-200 mm) from till. There is excellent agreement in the results of the size distribution obtained from the GID method and sieve analysis. The GID method results for size and shape parameters show high and very high repeatability. The particle angularity in the GID method has not been measured to acceptable level; the repeatability test shows some variability. The new methodology for total analysis of till applied the GID method at four different locations in Sweden. The total analysis included 3D size and shape distribution of coarse particles coupled to electrical resistivity, lithological distribution and magnetic susceptibility of the clasts. The results show clear difference in the till samples from the different sites. / <p>QC 20120828</p>

Made available in DSpace on 2015-03-26T13:53:14Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1644038 bytes, checksum: 68d3f82cdf154a7375fea21660c0f3e0 (MD5) Previous issue date: 2010-07-27 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / In laboratories in different regions of the country and in some cases, even in the same region, the procedures of particle size analysis are not standardized. There are differences in the chemical and physical dispersion techniques and in texture fraction quantification. There is no agreement on the most indicated chemical dispersant for particle-size analysis. Solutions of sodium hydroxide, sodium hexametaphosphate and sodium carbonate are the most commonly used. It is believed that the high pH of the NaOH solution favors the dispersion of variable-charge clay soils. Based on this statement the efficiency of NaOH, of [(NaPO3)n + Na2CO3] and of [(NaPO3)n + NaOH] solutions as chemical dispersants was tested in the particle-size analysis of two horizons of 26 reference soils of the state of Pernambuco. The treatments were arranged in a 26 x 2 x 3 factorial design (26 representative soils of Pernambuco, two horizons and three chemical dispersants {NaOH (D1), [(NaPO3)n + NaOH] (D2) and [(NaPO3)n + Na2CO3] (D3)}. A complete randomized block design was used with four replications. The dispersants were compared by the L&O test, which consists of a decision rule based on the F statistics and analysis of the average error and the correlation coefficient. The efficiency of dispersants was interpreted based on the clay proportion; the higher the clay proportion, the more effective the solution. A comparison of D2 = f (D1) and D3 = f (D1) showed no agreement between the dispersants. The intercept in the linear regression equation for the clay fraction was significant at 1% and negative, with highest clay values when using D1, while D2 and D3 were statistically equal. It was concluded that, given the higher clay proportion in the particle size analysis, NaOH was the most suitable dispersant to determine the texture of two horizons with 26 soil profiles in Pernambuco, representative of 82% of the total area of the state. / Laboratórios de diferentes regiões do País e, em alguns casos, da mesma região, não utilizam procedimentos uniformes para a execução da análise granulométrica. Há diferenças quanto à dispersão química, à dispersão física e a quantificação das frações texturais. Para o dispersante químico, não há unanimidade na indicação do mais apropriado para realização da análise granulométrica. Soluções de hidróxido de sódio e de hexametafosfato de sódio e carbonato de sódio são as mais utilizadas. Acredita-se que o elevado pH da solução de NaOH favorece a dispersão de solos com argilas de carga variável. Baseado nesta afirmativa objetivou-se testar a eficiência de soluções de NaOH, de [(NaPO3)n + Na2CO3] e de [(NaPO3)n + NaOH] como dispersantes químicos na análise granulométrica de dois horizontes de 26 solos de referência do Estado de Pernambuco. Os tratamentos corresponderam a um arranjo fatorial 26 x 2 x 3 (26 solos representativos do Estado de Pernambuco, 2 horizontes e 3 dispersantes químicos {NaOH (D1), [(NaPO3)n + NaOH] (D2) e [(NaPO3)n + Na2CO3] (D3)}. Utilizou-se delineamento experimental em blocos casualizadoscom quatro repetições. As análises granulométricas foram realizadas segundo a rotina do Laboratório de Física do Solo do Departamento de Solos da UFV. Na comparação dos dispersantes foi utilizado o teste L&O que consiste em uma regra decisória construída com base na estatística F, na avaliação do erro médio e na análise do coeficiente de correlação linear. O critério para considerar um dispersante mais efetivo foi a maior proporção de argila resultante da utilização dessa solução. Na comparação de D2 = f(D1) e D3 = f(D1) observou-se que não houve identidade entre os dispersantes. O intercepto encontrado na equação de regressão linear para a fração argila, significativo a 1 % e negativo, indica a obtenção de teores mais elevados de argila com D1. Houve igualdade na comparação de D2 com D3. Conclui-se assim que, considerando a maior proporção de argila na análise granulométrica, o NaOH foi o dispersante mais adequado na determinação da textura de dois horizontes de 26 perfis de solos do Estado de Pernambuco, representativos de 82 % da área total do Estado.

The main purpose of this study was to optimise the grain size distribution of the raw material mixture for the production of iron sinter. It well known that the constitution of the sinter mix is based on the knowledge of chemical composition and grain size distribution. Although Mittal Vanderbijlpark has fixed specifications on the physical and chemical properties of the sinter for optimal blast furnace performance, the particle size distribution of the sinter mix has not yet been optimized. This was achieved by using the granulation characteristics of the sinter mix and the green bed permeability tests. The influence of the moisture content of the feed, granulation time, and mean granule diameter on permeability was investigated on Thabazimbi and Sishen iron ore, as well as on their mixture with fluxes and without fluxes. The iron ore results indicated that the mixture containing 20% Thabazimbi iron ore and 80% Sishen iron ore with fluxes where the coke, lime and return fines were sized by removing the – 0.5 mm size fraction of the return fines and coke, and the 1 mm size fraction of lime has the highest permeability of all the studied mixtures. The sintering properties of the mixtures of optimised grain size distributions were also investigated and the results were very similar for all the mixtures and better than the base case mixture, which was not optimised with respect to grain size distribution. / Dissertation (MEng)--University of Pretoria, 2008. / Materials Science and Metallurgical Engineering / unrestricted

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Objective knowledge about quantity, composition and physicochemical characteristics of municipal solid waste (MSW) in the Czech Republic will form the basis for decision- making when considering processing facilities or regional waste management systems. As the country continues to streamline its legislation to the European Union's solid waste mandates, the results of these studies were employed by the Czech Ministry of Environment to optimise the national waste management strategy. This doctoral thesis focuses on the composition of MSW, primarily the mixed MSW from three types of households in the Czech Republic (urban, mixed and rural) differentiated by their heating methods and possibility of waste disposal. The respective experimental work and data-collection took place in years 2008 and 2009. Methodology used in the analyses is based on the sieve analysis of mixed MSW within predetermined grain size fraction and on the final manual sorting of the waste by material categories. The physicochemical characteristics were measured according to the standard analysis methods. The composition of mixed MSW in urban and mixed households are similar. Some of the biggest differences were found in the quantities of certain subsample categories, especially fine fraction (matter smaller than 8 mm), between...

Feather pecking is a serious problem in laying hen husbandry, which can lead to feather damage, performance losses and economic disadvantages. In this context, feed has been identified as an important factor, whereby scientific knowledge is primarily available on the effect of ingredients but hardly on the feed structure. In this study, feed samples from feather pecking and non-feather pecking herds from production farms were analyzed for their nutrient contents and feed particle sizes. More coarser (>2.00 mm) and fewer medium and finer feed particles (≤1.60 mm) were found in the feed of the flocks affected by feather pecking. The coarser components contained lower levels of nutrients important for preventing feather pecking (e.g., methionine, sodium). The study demonstrated that a feed structure that is too coarse can be considered a risk factor for feather pecking. / Die Studie untersucht die Zusammensetzung der Futterpartikelfraktionen und deren Nährstoffgehalte in Legehennenfutter. Hierfür wurden 103 Futterproben von federpickenden (AH, n=37) und nicht-federpickenden Herden (CH, n=66) von Produktionsbetrieben mittels trockener Siebanalyse und Nährstoffanalytik untersucht. In den AH zeigten sich in der Futterstruktur im Vergleich zu den CH höhere Anteile an Partikeln >2,50 mm (MW ± STW: CH: 11,0 ± 8,5 %, AH: 24,9 ± 14,3 %) und 2,00-2,50 mm (CH: 11,2 ± 5,3 %, AH: 15,7 ± 5,7 %) bei niedrigeren Anteilen der Fraktionen 1,01-1,60 mm (CH: 22,9 ± 4,9 %, AH: 17,8 ± 5,7 %), 0,51-1,00 mm (CH: 25,5 ± 8,2 %, AH: 16,0 ± 6,8 %) und ≤0,50 mm (CH: 15,4 ± 5,0 %, AH: 11,0 ± 4,8 %) (p<0,001). Die Futter der AH (1470,8 ± 343,9 μm) wiesen dabei auch einen höheren geometrischen Durchmesser aus (GMD) im Vergleich zu den CH (1113,3 ± 225,7 μm) auf (p<0,001). Die vorgefundenen Anteile der Partikelgrößenfraktionen 1,01-1,60 mm und ≥2,50 mm lagen außerhalb des empfohlenen Referenzbereichs (p<0,001). Die Gehalte an Rohasche (CH: 130,3 ± 18,8 g/kg, AH: 115,9 ± 24,3 g/kg), Lysin (CH: 8,2 ± 1,0 g/kg, AH: 7,7 ± 1,2 g/kg), Methionin (CH: 3,4 ± 0,5 g/kg, AH: 3,2 ± 0,6 g/kg) und Natrium (CH: 1,7 ± 0,4 g/kg, AH: 1,3 ± 0,4 g/kg) waren bei den AH niedriger als in den CH (p≤0,041). Im Modell der logistischen Regression zeigten sich das Tieralter (p=0,041) und der GMD (p<0,001) als signifikante Einflussfaktoren auf das Auftreten von Federpicken. Anhand der Studie konnte gezeigt werden, dass eine zu grobe Futterstruktur als Risikofaktor für Federpicken zu betrachten ist.

The work deals with the examination of repression and segregation in asphalt mixtures. The theoretical part is monitoring the current situation about the problem of segregation, which mainly refers to the practical adjustments during laying „risking“ asphalt mixtures on the formation of segregated places in the shelter layers of roads. The practical parts of the thesis are summarised measurements on six samples of the most commonly used asphalt mixtures to determine the segregation depending on the selected parameters. The work is describing and valorising a test for determining segregation according to ČSN EN 12697-15.

Para la presente investigación de tesis desarrollada entre los distritos de Imperial y Pampas, provincia de Tayacaja, en el departamento de Huancavelica, se tiene como unidad de análisis a 60 muros de contención, donde se aplicó criterios muestréales de 23 muros f´c 210 kg/cm2. Como resultados alcanzados se logró elaborar concreto hidráulico de calidad usando agregado fino marginal con el cual se pudo satisfacer los parámetros de resistencia y durabilidad. Para demostrar la durabilidad se realizaron distintos ensayos; los que no cumplieron con las especificaciones de la norma EG-2000 fueron el de Equivalente de arena MTC E 114, Material que pasa el Tamiz N°200 MTC E 202 y Análisis granulométrico por tamizado ASTM C 136, por lo cual se efectuaron análisis más rigurosos como: el ensayo de Valor de azul de metileno y el ensayo de Análisis petrográfico macroscópico y microscópico en agregados para concreto ASTM C 295, donde se obtuvo como resultado que la arena no presenta elementos activos en su composición, lo que quiere decir que ante las condiciones ambientales de la zona estos elementos no se expanden ni se contraen y adicionalmente como medida de control se diseñó la mezcla de concreto hidráulico con aditivo incorporador de aire AirMix-200. Del mismo informe petrográfico se concluyó que la composición principal del agregado es la caliza, la cual es materia prima para la elaboración del cemento, que de alguna manera adicional ayuda a cumplir satisfactoriamente el parámetro de resistencia. Así mismo quedó demostrado que a través de ensayos a compresión no confinada de testigos de concreto, se alcanzó resistencias superiores a lo requerido en la norma EG-2000. Research for this thesis developed between the districts of Imperial and Pampas, Tayacaja province, in the department of Huancavelica, it has the analysis unit 60 retaining walls, where 23 sample criteria applied walls f´c 210 kg/cm2. Results obtained are as elaborate hydraulic concrete achievement of marginal quality using fine aggregate with which it was able to satisfy the parameters of strength and durability. To demonstrate the durability various tests were performed; those who do not comply with the specifications of the EG-2000 were rule the sand equivalent MTC E 114, passes what material the sieve No. 200 MTC E 202 and sieve analysis ASTM C 136, here by which they were made Analysis More rigorous like: The test value of methylene blue and testing of macroscopic and microscopic petrographic analysis in paragraph aggregate concrete ASTM C 295, where it resulted the sand without presents elements active in their composition, which means they say to the area Environmental Conditions These elements do not expand or contract and additionally as a control measure of self-design hydraulic concrete mix with entraining admixture AirMix-200 air. Same petrographic report concluded that the composition of the director of aggregate is limestone, which is a raw material for the production of cement, which in some additionally helps one perform satisfactorily resistance parameter. Also it demonstrated that one through essays of unconfined compressive concrete witness, higher strengths than required was reached in the EG-2000 standard.

The diploma thesis deals with using of recycled aggregate of concrete for base layers of pavement. The work is divided into practical and theoretical part. The theoretical part deals with basic concepts of construction and demolition waste, production, development and management of this waste in the Czech Republic. It also focuses on the principle of recycling and the use of recycled concrete in the Czech Republic and abroad. The practical part of the thesis deals with laboratory testing and assessment of recycled aggregates in bound, unbound and grouted courses layers of the base layers of roads.