The objective of this research was to investigate the effect of applied compressive strain in various environments, on the strength and stiffness of compressed wood samples. It is believed that transverse compression of wood at specific conditions of temperature and moisture will result in improved mechanical properties, which can be attributed to increased density and perhaps other physical or chemical changes. Specimens of both mature and juvenile southern pine (Pinus taeda) and yellow-poplar (Liriodendron tulipifera) were compressed radially at three different temperature, and moisture content conditions relevant to the glass transition of wood. Ultimate tensile stress and longitudinal modulus of elasticity were obtained by testing compressed, uncompressed and control samples in tension parallel-to-grain. Strain measurements were performed using laboratory-built clip-on strain gauge transducers. Results of the tensile tests have shown an increase in the ultimate tensile stress and modulus of elasticity after all densification treatments. Scanning electron microscopy was employed for observing changes in cellular structure of densified wood. Existence of the cell wall fractures was evaluated using image processing and analysis software. Changes in cellular structure were correlated with the results of the tensile test. Chemical composition of wood samples before and after desorption experiments was determined by acid hydrolysis followed by high performance liquid chromatography (HPLC). The results of the chemical analysis of the wood specimens did not reveal significant changes in chemical composition of wood when subjected to 160 °C, pure steam for up to 8 hours. The results of this research will provide information about modifications that occur during wood compression and will result in better understanding of material behavior during the manufacture of wood-based composites. In the long run, modification of wood with inadequate mechanical properties can have a significant effect on the wood products industry. Low density and juvenile wood can be used in new high-performance wood-based composite materials instead of old-growth timber. / Master of Science

The bond performance and surface energy of hygro-thermal compression densified wood were studied using comparisons to hygro-thermally treated and control yellow-poplar (Liriodendron tulipifera). Bond performance was studied using opening mode double cantilever beam fracture testing and cyclic boiling of one half of all fracture samples. Phenol formaldehyde film (PF-film) and polymeric diphenylmethane diisocyanate (pMDI) were the two different adhesives used to bond fracture samples. Hygro-thermal samples bonded with PF-film had significantly higher fracture toughness than control samples, while no difference was found for densified samples. Densified samples bonded with pMDI had significantly higher fracture toughness than control samples while no change was seen for hygro-thermal samples. Boil cycling reduced fracture toughness of hygro-thermal fracture samples only, irrespective of adhesive type. Surface energy was studied using sessile drop contact angle measurement and the Chang model of acid-base, surface energy component calculation. Water, glycerol, formamide, ethylene glycol, and -Bromonapthalene were used as probe liquids. Densified and hygro-thermally treated yellow-poplar had significantly higher contact angles than control samples. The contact angle trends for densified and hygro-thermally treated wood were found to be the same. Total surface energy as well as the polar and acid components of surface energy decreased with hygro-thermal treatment. The dispersive and base components of surface energy increased with hygro-thermal treatment. / Master of Science

Raw biomass material is bulky, high in void fraction, and very low in transportation efficiency. Furthermore, biomass dissipates quickly in harsh environments of high heat furnaces because of its relatively low calorific value (BTU/lb) and has grinding or size degradation properties highly dissimilar from commonly-used fossil fuels like coal. Therefore, the development of transformational technologies are necessary to convert raw biomass into high-value and useful products of high hardness and calorific value without requiring excessive process energy. This thesis investigates the sustainability of densified biomass fuels. In addition, a procedure that converts raw biomass from agro/forest industry waste into a fuel source known as semi-carbonized densified biomass (SCDB) is shown to have the necessary performance qualities that are conducive to applications involving the harsh conditions of high heat furnaces. The SCDB is produced at temperatures between 115-230°C and pressures between 8-25 MPa. The raw biomass is transformed into a densified fuel source with maximum compressive strengths between 60-200 MPa and calorific values between 18-23 MJ/kg, which are essential to operating in high heat furnace environments. The procedural steps and equipment used to manufacture this densified fuel source are outlined in detail along with experimental results and discussions of initial testing.

No description available.

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / This study aimed to investigate the mechanical and durability properties of recycled aggre-gate concrete with a ternary binder system and optimized mix proportion. Two concretebatches were developed using a densified mix design approach (DMDA) to evaluate therequired mix proportions. Batch I have GGBS content varied at 0%, 10%, 20%, 30%, 40% and50% at constant w/b ratio of 0.45, while batch II concrete mix have varied water/binder ratios:0.3, 0.35, 0.4, 0.45 and 0.5 at constant GGBS replacement level of 30%. The fine aggregate(river sand) of the two batches was blended with fly ash at optimum loose packing density(FA + Sand) and superplasticizer (SP) was incorporated in the mix at a constant level of 1.4%.A control mix comprising of natural aggregate was also developed. The results obtainedshowcased the feasibility of producing structural concrete with recycled aggregates usingGGBS and fly ash. The mechanical and durability properties were best at 30% GGBS contentand 0.35 water/binder ratio. The DMDA for mix proportion adopted for RAC contributed sig-nificantly to improving its properties when compared to NAC, especially at the optimumobserved RAC mix with compressive strength of 52 MPa. Also, the mix demonstrated goodpermeability resistance in terms of chloride-ion ingress and capillary water absorption.

Submitted by GABRIEL ALBUQUERQUE DE LYRA null (gabriel.lyra@hotmail.com) on 2016-12-19T19:21:33Z No. of bitstreams: 1 Tese Gabriel Lyra.pdf: 1897866 bytes, checksum: 8ba973ed81d889444a889d0064b3f3ed (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-12-21T11:07:29Z (GMT) No. of bitstreams: 1 lyra_ga_dr_bot.pdf: 1897866 bytes, checksum: 8ba973ed81d889444a889d0064b3f3ed (MD5) / Made available in DSpace on 2016-12-21T11:07:29Z (GMT). No. of bitstreams: 1 lyra_ga_dr_bot.pdf: 1897866 bytes, checksum: 8ba973ed81d889444a889d0064b3f3ed (MD5) Previous issue date: 2016-10-14 / Como grande pilar de sustentação econômica, a agricultura brasileira mantém-se em constante desenvolvimento e adaptação para atender as demandas de mercado, exigindo dos produtores rurais atualização de seus processos produtivos. Uma das formas mais comuns de incrementar a produção agrícola é aumentar a população de plantas na semeadura, visando acréscimo em produtividade. Contudo, na cultura do algodão a semeadura com espaçamento estreito entre fileiras tem como maior finalidade encurtar o ciclo produtivo, possibilitando o menor uso de defensivos agrícolas, principalmente de inseticidas e fungicidas, tendo em vista o grande número de aplicações. Esta prática foi implementada inicialmente nos Estados Unidos nos anos 70 e vem sendo adotada desde então em outros países, mas a grande limitação desse processo está na dificuldade da colheita, tornando a operação menos eficiente, principalmente no que diz respeito as perdas, sem deixar de lado a qualidade da fibra colhida. Visando minimizar estas perdas e manter as qualidades do algodão adensado, foi proposto nesse trabalho avaliar o desempenho de uma colhedora e a qualidade da fibra do algodão cultivado em espaçamentos tradicional simples e duplo combinado. A semeadura com utilização de espaçamentos duplos combinados entre fileiras permite aumentar a população de plantas sem mudar drasticamente o sistema operacional de colheita já consolidado, uma vez que a duas fileiras com menor espaçamento podem ser colhidas com a mesma máquina utilizada para o espaçamento tradicional de semeadura, por isso durante a condução do experimento foi realizada a implantação de quatro tipos de espaçamento: fileiras duplas espaçadas em 15x75 cm, 18x72 cm, 20x70 cm e o tradicional de 90 cm entre as fileiras de cultivo. Nos espaçamentos duplos combinados a densidade de semeadura foi dobro em relação a semeadura do espaçamento simples convencional. Os parâmetros avaliados foram: população de plantas ao fim do ciclo, número de capulhos por planta, produtividade, qualidade da fibra colhida, consumo de combustível da colhedora e perdas pós-colheita. As análises das características e qualidade da fibra foram realizadas em Laboratório de Classificação de Fibras por meio do sistema HVI (High Volume Instrument). Os resultados obtidos foram submetidos a análise de variância e as médias comparadas pelo teste Tukey a 5% de significância. Os resultados mostraram que o número de capulhos por planta é significativamente maior quando o algodão é cultivado em espaçamento simples convencional, média de 11,2 capulhos por planta, enquanto nos espaçamentos duplos combinados a média foi de 7,5 capulhos por planta, contudo, por conta da maior densidade populacional não houveram diferenças significativas entre as produtividades. O consumo de combustível da colhedora não foi afetado pela densidade populacional, ou pelos tipos de espaçamentos duplos combinados. As perdas pós-colheita foram significativamente maior no algodão cultivado com espaçamento duplo combinado de 20x70 cm, média superior a 18%, enquanto nos demais espaçamentos duplos combinados as perdas ficaram com médias próximas a 10%, e média de 12,4% no espaçamento simples convencional. De maneira geral a qualidade da fibra do algodão colhido não apresentou diferenças entre os espaçamentos de cultivo simples convencional e duplo combinado. / Brazilian agriculture is in constant development and adaptation to meet market demands, requiring rural producers to update their production processes. One of the most common ways of increasing agricultural production is to increase the population of plants at sowing, aiming to expand productivity. However, in the cotton crop, sowing with narrow spacing between rows has as main purpose to shorten the productive cycle, making it possible to use less pesticides, mainly insecticides and fungicides, in view of the large number of applications. This practice was initially implemented in the United States in the 1970s and has since been adopted in other countries, but the major limitation of this process lies in the difficulty of harvesting, making the operation less efficient, especially with regard to losses, without leaving aside the quality of the harvested fiber. Aiming to minimize these losses and maintain the qualities of the higher density cotton, it was proposed in this study to evaluate the performance of a harvester and the quality of cotton fiber grown in traditional single and double combined spacings. Sowing with the use of double combined spacings between rows allows to increase the population of plants without drastically changing the harvesting system already consolidated, since the two rows with smaller spacing can be harvested with the same machine used for the traditional seeding spacing, so during the conduction of the experiment was performed the implantation of four types of spacing: double rows spaced in 15x75 cm, 18x72 cm, 20x70 cm and the traditional one of 90 cm between the rows of cultivation. In the combined double spacings the sowing density was double in relation to conventional simple spacing. The parameters evaluated were: Population of plants at the end of the cycle, number of balls per plant, productivity, quality of harvested fiber, harvester fuel consumption and post-harvest losses. The analysis of fiber characteristics and quality was carried out in Laboratory of Fiber Classification through the HVI (High Volume Instrument) system. The results were submitted to analysis of variance and the means were compared by the Tukey test at 5% of significance. The results showed that the number of balls per plant is significantly higher when the cotton is cultivated in conventional single spacing, with an average of 11.2 balls per plant, while in the combined double spacings the average was 7.5 balls per plant. However, due to the higher population density there were no significant differences between the productivities. The fuel consumption of the harvester was not affected by the population density or by the combined double spacing types. Postharvest losses were significantly higher in cotton grown with combined double spacing of 20x70 cm, average higher than 18%, while in the other combined double spacings the losses were with averages close to 10%, And a mean of 12.4% in conventional single spacing. In general, the quality of the harvested cotton fiber did not show differences between conventional and double combined single crop spacings.

Made available in DSpace on 2016-12-12T20:12:32Z (GMT). No. of bitstreams: 1 PGEF15MA051.pdf: 1474402 bytes, checksum: caefe48730a523187b058411009c1fc0 (MD5) Previous issue date: 2015-07-22 / The pellets produced from forest biomass appear alternatively in obtaining thermal and electrical energy. Biomass compressed manufacturing must meet some standards of quality that are based on standards, however it is known that in Brazil there is no specific standard for the manufacture of that product. In this way, the study sought to determine the quality of the pellets from forest biomass produced in Santa Catarina, based on international standards, aiming at the proposal of criteria for the establishment of a State quality standards for this energy resource. Nine samples were collected in the State, in which they were certain the properties: physical (size, apparent density and density of unit), mechanical (durability and fine content) and energy (moisture content; immediate analysis and calorific value) of pellets. After the completion of the analysis the data were compared with the standards: European (CEN/TS 14961), North American (USA PFI), Italian (CTI-R 04/5), German (DIN 51735), Swedish (SS 187120), Austria (Onörm M7135) and with the international standard ISO 17225-2. From this, a proposal of normalization for the State of Santa Catarina. The average values of the properties were: 6.58 mm diameter; 17,31 mm length; apparent density of 663,46 kg/m³; 1,70 unit density kg/m³; 7,89% moisture content; volatile content of 81,29%; fixed carbon of 18,33%; from 0,38% ash content; 4827 superior calorific value Kcal/kg; durability of 99,07% and percentage of 1,05% fines. The pellets produced in Santa Catarina feature hig The shavings of Pinus spp. is used by all producers of pellet formation of the State, thus, a norm for this energy resource does not require subdivisions depending on the raw material used. The standard should present only categories depending on the final use of the product, which is directed at the service sector and the manufacturing sector. All properties reviewed are important indicators of the quality of the pellets and must appear in the standard. On the information researched and results obtained, it becomes possible to propose a standardization for pellets in Santa Catarina. The quality and meet the requirements laid down by the main international standards / Os péletes produzidos a partir de biomassa florestal surgem como alternativa na obtenção de energia térmica e elétrica. A fabricação dos compactados de biomassa precisa atender alguns padrões de qualidade que são fundamentados por normas, no entanto sabe-se que, no Brasil não existe uma norma específica para a fabricação desse produto. Desta forma, o trabalho buscou determinar a qualidade dos péletes de biomassa florestal produzidos em Santa Catarina, com base em normas internacionais, visando à proposição de critérios para a elaboração de uma normalização estadual de qualidade para este recurso energético. Foram coletadas nove amostras no estado, nas quais foram determinadas as propriedades: físicas (dimensões, densidade aparente e densidade da unidade), mecânicas (durabilidade e teor de finos) e energéticas (teor de umidade; análise imediata e poder calorífico) dos péletes. Após a realização das análises os dados foram comparados com as normas europeia (CEN/TS 14961), norte-americana (EUA PFI), italiana (CTI-R 04/5), alemã (DIN 51735), sueca (SS 187120), austríaca (Onörm M7135) e com a norma internacional ISO 17225-2. A partir disso, foi elaborada uma proposição de normalização para o estado de Santa Catarina. Os valores médios das propriedades foram: diâmetro de 6,58 mm; comprimento de 17,31 mm; densidade aparente de 663,46 kg/m³; densidade da unidade de 1,70 kg/m³; teor de umidade de 7,89 %; teor de materiais voláteis de 81,29 %; carbono fixo de 18,33%; teor de cinzas de 0,38 %; poder calorífico superior de 4827 Kcal/kg; durabilidade de 99,07% e porcentagem de finos de 1,05 %. Os péletes produzidos em Santa Catarina apresentam elevada qualidade e atendem as exigências estabelecidas pelas principais normas internacionais. A maravalha de Pinus spp. é utilizada por todos os produtores de péletes do estado, dessa forma, uma norma para esse recurso energético não requer subdivisões em função da matéria-prima utilizada. É necessário que a norma apresente categorias em função do uso final do produto, que é direcionado ao setor de serviços e setor industrial. Todas as propriedades analisadas são importantes indicadores da qualidade dos péletes e precisam constar na norma. Diante das informações pesquisadas e resultados obtidos, é possível a proposição de uma normalização para péletes em Santa Catarina

I detta examensarbete behandlas en jämförelse mellan två olika material utifrån LCC för GC-broar. Dessa är stål och Delignified Densified Wood (DDW). Samhället är i behov av att utvecklas inom ett mer hållbart- och anpassad till klimatkraven. Detta innebär att det ställs krav på Trafikverket. Dessa krav innebär bland annat att byggnadsmaterial behöver utvecklas. Sverige har god tillgång till skog och träframtagning. Trafikverket bör nyttja mer av träets potential. Denna studie har därför gjorts för att bedöma DDW som är ett träbaserat material utifrån intervjuer och livscykelkostnadsanalys (LCC-analys). LCC är ett tillvägagångsätt för att få en totalbild över en produkts samtliga kostnader under dess livslängd. Det vill säga att för en bro bedöms kostnaderna från projektering till rivning. Syftet med LCC-analys är att hitta den mest lönsamma investeringskostnad som uppfyller dagens samhällskrav. DDW är framtagen av Forskare vid Marylands Universitet. Forskningen har observerat att obehandlat trä går att få lika starkt som stål. Processen innebär att ligninet avlägsnas och träet placeras i tryck under värme på cirka 100 C°. Detta leder till att cellulosafibrerna pressas samman och blir hårdare. Det resulterar förenklat sagt att träet blir mycket hårdare, tåligare och starkare och går att forma och böja. Resultatet av examensarbetet tyder på att DDW inte är lämpligt just nu som konstruktionsmaterial i utomhusklimat och inte är ekonomiskt lönsamt. DDW är vetenskapligt intressant och bör forskas vidare. I dagsläget rekommenderas inte DDW som GC-bromaterial. Trafikverket bör bygga mer GC- broar av trä som passar väl som GC-bromaterial. / n this thesis a comparison is made between two different construction materials based on LCC for pedestrian and cycle bridges. These materials are steel and Delignified Densified Wood (DDW). Today ́s society needs to develop with more sustainable and climate-friendly construction. This need imposes demands on the Swedish transport administration, e.g. that building materials need to be developed. One viable material for Sweden, since it has good access to forestry and wood production, is wood. The Swedish transport administration should use more of the potential of wood. This study therefore assesses DDW, which is a wood-based material, based on interviews and life cycle cost analysis (LCC-analysis). LCC is a way of getting a complete picture of a product's entire costs during its lifespan. In the case of a bridge, the costs are estimated from planning to demolition. The purpose of LCC analysis is to find the most profitable investment cost that meets today's social requirements. DDW is developed by researchers at Maryland University. Researchers have observed that natural wood can be as strong as steel. The process involves removing lignin and placing it under pressure at a temperature of about 100 ° C. This causes the cellulosic fibers to compress and become harder. This simply means that the wood becomes much harder, more durable and stronger, and can also shape and bend. The result of the thesis suggests that DDW is not suitable at present as construction material in outdoor climate and is not economically profitable. DDW is scientifically interesting and should be researched further.

This work includes two unrelated areas of research. The first portion of this work involved combusting densified refuse derived fuel (dRDF) with coal and studying the effect that Ca(0H)2 binder had on reducing polycyclic aromatic hydrocarbon (PAH) and polychlorinated biphenyl (PCB) emissions. The second area of work was directed at developing nondestructive infrared techniques in order to aid in the analysis of postage stamp adhesives. With Americans generating 150-200 million tons a year of Municipal Solid Waste (MSW) and disposing of nearly ninety percent of it in landfills, it is easy to understand why American landfills are approaching capacity. One alternative to landfilling is to process the MSW into RDF. There are technical and environmental problems associated with RDF. This work provides some answers concerning the amount of PAH and PCB emissions generated via the combustion of RDF with coal. It was found that the Ca(OH)2 binder greatly reduced both the PAH and the PCB emissions. In fact, PAH emissions at the ten-percent level were reduced more by using the binder than by the pollution control equipment. If the Ca(0H)2 binder can reduce not only PAH and PCB emissions, but also other noxious emissions, such as acid gases or dioxin, RDF technology could soon be the answer to the current landfill problems. The second portion of this work focused on developing a method to analyze stamp adhesives nondestructively. Using this method, it was fairly easy to differentiate among the three different types of adhesives that have been used by the United States Postal Service: gum arabic, dextrin, and polyvinyl alcohol. Differences caused by changes in chemicals added to the adhesives were also detected. Also, forgeries were detected with as much success, if not more, than by conventional methods. This work also led to the construction of equipment that allows large samples to be analyzed by reflectance infrared methods.

No description available.