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<p>The term biofuel is referred to as liquid or gasous fuels for the transport sector that are produced from biomass. Producing biofuels from cellulose- rich materials are considered as relevant technology nowadays.</p><p>There is a research and technological development project for years at Malardalens Högskola about bioethanol and biogas production, and the university joined to the Vaxtkraft project in Vasteras, Sweden, aims to produce biogas out of ley crop and organic waste.</p><p>The purpose of my study was to analyse the efficiency of producing transportation fuels, spezifyed ethanol and biogas from straw.</p><p>Extraction of sugar from straw under different conditions with respect to pH, temperature and extraction time were studied. Thereafter biogasification with bacteria to form CH4 and ethanol fermentation with Saccharomyces was performed and the gas production measured.</p><p>The extractions were carried out separately at 121 °C and 140-145 °C, with 20, 40, 60, 120 minutes extraction time. The pH during the processes was set to 5 and 3 with buffer solution. To consider the extraction rate, the better conditions are lower pH, higher temperature and longer extraction time.</p><p>The results show the optimal extraction is performed at 140-145 °C for 120 minutes with pH 3.</p><p>The gasification was carried out at 37 °C with using Baker’s yeast. The results indicate that in contrast to the extraction, the gasification is better with the samples which extraction was carried out at lower temperature and higher pH. The best gasification was achieved by the samples with 121°C and pH 5 extraction irrespectively of the extraction time, although they had the worst extraction rate results.</p><p>More research and detailed quality analysis are needed to determine the reason of this seeming contradiction</p>

Columbia River sediment was irradiated with ultraviolet light to determine if organic material could be removed without altering the sorptive properties of the hydrous oxides of iron and manganese. A laboratory preparation of Zn-65 spiked hydrous ferric oxide was subjected to ultraviolet irradiation in order to assess the photochemical effect upon Zn-65 release. The photochemically induced release of Mn-54 present on the Columbia River sediment was used to assess the effect on the hydrous oxides of manganese. The ultraviolet irradiation proved effective in removing up to 68% of the sedimentary organic material in 17 hours without causing release of Zn-65 or Sc-46. While the ultraviolet irradiation had no effect upon Zn-65 release from laboratory preparations of hydrous ferric oxides and Zn-65 spiked montmorillonite, a significant release of Mn-54 resulted from the photolysis treatment. The removal of Mn-54 was not accompanied by the release of sorbed Zn-65 or Sc-46 (nuclides expected to be sorbed by hydrous oxides), nor did there appear to be any permanent change in the nature of the Mn-54 on the sediment. Although it is possible that the hydrous oxides of manganese are affected by the ultraviolet treatment, it is likely that another species, such as the carbonate, is the species involved. Photo-oxidation appears to provide a method of obtaining sediments with substantially reduced organic content without affecting the sorptive properties of hydrous oxides or clay minerals. This result should allow the use of uptake studies to determine the importance of organic material in trace metal sorption by sediments. / Graduation date: 1972

Manual and automatic solvent extraction techniques were used to concentrate organic material from natural waters. Field and laboratory extractions were compared to determine the most probable method and best solvents for efficient concentration of organic material from estuarine and sea waters. The large scale extraction processes utilizing extractors made from 55 gallon drums were operated both by manually moving perforated metal discs through the water and solvent for mixing and by bubbling air through the aqueous-solvent mixture. Resulting samples proved large enough for the detection of short-chain fatty acids (carbon length 1 through 10). Identification of organic constituents was by gas chromatography-mass spectroscopy. Other portions of these samples were separated by column chromatography with subsequent analysis by infrared, visible, ultraviolet, and mass spectroscopy. The proximity of the Hanford Atomic Product Operations to the collecting area caused some of the organics to be labeled with trace amounts of radionuclides. A counter-current pulse column extractor was used at sea aboard the Research Vessel YAQUINA. The organic solvent, hexone, used in this extraction was distilled before and after the extraction with various fractions of solvent being kept for control. The extraction was carried out under varying chemical and physical conditions. The hexone was back-extracted into hydrochloric acid, sodium bicarbonate, or sodium hydroxide before analysis by flame-ionization gas chromatography and mass spectroscopy. Other portions of the product hexone were analyzed for total solid matter recovered and carbon, hydrogen, and nitrogen content. Small intermediate scale extractions were carried out in the laboratory using several solvents. Resulting organic material was analyzed by tandem gas chromatography-mass spectroscopy. Where possible, organic derivatives were prepared to aid in the identification of the recovered organic material. The advantages and disadvantages of large scale extractions and small laboratory procedures were discussed. / Graduation date: 1967

A simple process to obtain onion oil by direct solvent extraction was proposed. Several solvents commonly utilized in the food industry were tested for their selectivity in the extraction of the oil of onion. Diethyl ether and methylene chloride appeared to be the most suitable solvents for the extraction operation. The direct solvent extraction method produced a yield of onion oil approximately seven times higher than the yield obtained by the steaim distillation method. A process of fermentation of the ground raw onions was used prior to the solvent extraction operation. This produced an improvement in the onion oil yield of 60% over the normal solvent extraction method. In order to determine the quality of the onion oil obtained, refractive index, specific gravity, melting point, and sulfur content were determined. Sulfur content in the onion oil obtained by the method proposed here had one-third (weight basis) of the sulfur content of commercial onion oil. Two organoleptic evaluations were conducted for commercial onion oil and for the onion oil obtained by direct solvent extraction: odor threshold determination and comparative flavor evaluation. The commercial onion oil showed a lower threshold concentration (1.6 ppb) than the onion oil obtained in the laboratory (8.4 ppb). With respect to the comparative flavor tests, the test panels did not detect a statistically significant difference between the flavor of commercial onion oil and the oil obtained by the method proposed here. / Graduation date: 1982

Fractures in carbonate strata are often associated with dissolution features such as karst cavities along the fracture plane. Integration of full resolution 3D GPR data and outcrop observation allows the visualization and quantification of fractures and karst cavites in three dimensions. Three 3D GPR cubes were acquired in the Solvay quarry, Provence region, SE France. The quarry exposes an intensly fractured and karstified shallow-water Barremian carbonates with matrix porosity less than 1.8%. The quarry walls provide the 2D information of the fractures (location, type, orientation, dip, length, aperture, spacing and stratigraphic position) and the karst (location, size, shape, stratigraphic position and relationship with fractures), that were documented using 1D scan line measurement. Several deformation features are observed in the quarry, dominated by meter-scale joints and tension gashes, and also minor faults, burial and tectonic-related stylolites. Three major fracture orientations (E-W, NW-SE and N-S) were found in the quarry with a non-uniform distribution influenced by structural position relative to major structural features (eg: large fractures (>10m) and faults). Interpretation of 3D GPR data reveals one major fracture orientation (NE-SW) that was not observed in the outcrop because it is oriented parallel with the quarry wall. Besides fractures, karst were also documented in outcrop as well as in 3D GPR data. Combination between 3D GPR and outcrop observation show that in the Solvay quarry karst occur along fracture plane and preferentially at fracture intersections. The karst are decimeter to meter-size karst which are below the resolution of 3D seismic reflection. Quantification of karst in the quarry show that karst size-frequency distribution follows power-law distribution, where small karst is more common and large karst is less common. The volume of karst in the quarry is up to 3.8% of the total rock volume. The power-law scaling relationship and the quantification of the sub-seismic karst volume will help predicting karst arrays in wide range of sizes in subsurface reservoirs, where visualization of karst is restricted to the resolution of 3D seismic data.

This thesis describes a divide-and-conquer algorithm to improve the 3D boundary element method (BEM) for capacitance extraction. We divide large interconnect structures into small sections, set new boundary conditions using the borderfor each section, solve each section, and then combine the results to derive the capacitance. The target application is critical nets where 3D accuracy is required. The new algorithm is a significant improvement over the traditional BEMs and their enhancements, such as the "window" method where conductors far away are dropped, and the "shield" method where conductors hidden behind other conductors are dropped. Experimental results show that our algorithm is 25 times faster than the traditional BEM and 5 times faster than the window+shield method, for medium to large structures. The error of the capacitance computed by the new algorithm is within 2% for self capacitance and 7% for coupling capacitance, compared with the results obtained by solving the entire system using BEM. Furthermore, our algorithms gives accurate distributed RC, where none of the previous 3D BEM algorithms and their enhancements can.

The term biofuel is referred to as liquid or gasous fuels for the transport sector that are produced from biomass. Producing biofuels from cellulose- rich materials are considered as relevant technology nowadays. There is a research and technological development project for years at Malardalens Högskola about bioethanol and biogas production, and the university joined to the Vaxtkraft project in Vasteras, Sweden, aims to produce biogas out of ley crop and organic waste. The purpose of my study was to analyse the efficiency of producing transportation fuels, spezifyed ethanol and biogas from straw. Extraction of sugar from straw under different conditions with respect to pH, temperature and extraction time were studied. Thereafter biogasification with bacteria to form CH4 and ethanol fermentation with Saccharomyces was performed and the gas production measured. The extractions were carried out separately at 121 °C and 140-145 °C, with 20, 40, 60, 120 minutes extraction time. The pH during the processes was set to 5 and 3 with buffer solution. To consider the extraction rate, the better conditions are lower pH, higher temperature and longer extraction time. The results show the optimal extraction is performed at 140-145 °C for 120 minutes with pH 3. The gasification was carried out at 37 °C with using Baker’s yeast. The results indicate that in contrast to the extraction, the gasification is better with the samples which extraction was carried out at lower temperature and higher pH. The best gasification was achieved by the samples with 121°C and pH 5 extraction irrespectively of the extraction time, although they had the worst extraction rate results. More research and detailed quality analysis are needed to determine the reason of this seeming contradiction

The extraction of pentachlorophenol (PCP) from pressure treated wood wafers with supercritical carbon dioxide has been studied. Experimental data were obtained for the effects of pressure (17.5 - 25.0 MPa), temperature (313 - 353 K), flow rate (1 - 3 ml/min at supercritical conditions), and sample size (0.8 x 10 x 50 mm and 2.2 x 10 x 50 mm) by measuring the effluent concentration versus time. A fundamental model was developed which includes rates of intraparticle diffusion, external film mass transfer, desorption and the initial distribution of PCP between the pore volume (cell lumen) and pore surface (cell wall) of wood wafers. The intraparticle diffusion and external mass transfer rates are combined in terms of an overall mass transfer coefficient derived from the assumption of a parabolic concentration profile of PCP inside the wafer pores. The initial distribution of PCP between cell lumen and cell wall was determined by fitting the mathematical model to dynamic extraction rate data. The desorption rate was very small for all the extraction conditions, and extraction rate increased with the pressure, temperature, and flow rate because the combined mass transfer increased. Similar values of mass transfer coefficient were achieved for two different sample sizes: 0.8 x 10 x 50 mm and 2.2 x 10 x 50 mm. / Graduation date: 1994

A concern with organic farming is for the depletion of soil phosphorus. The objectives of this study were to determine which organic management systems deplete soil phosphorus and whether arbuscular mycorrhizal fungi (AMF) could assist crops in taking up phosphorus in these systems. The research site was a 14 year-old study at Glenlea, Manitoba, having 3 different 4-year rotations under organic and conventional management: forage-grain ± manure-compost, grain-only, and a restored tall grass prairie. The modified Hedley procedure revealed organic systems to have lower concentrations of labile phosphorus than conventional but recalcitrant fractions did not differ (P < 0.05). Nitrogen was limiting in the organic grain-only rotation; phosphorus in the organic forage-grain. Mycorrhizal colonization as arbuscules was higher in organic than conventional systems (P < 0.05). To prevent phosphorus limitation, we suggest high-export organic rotations be balanced with sufficient rates of manure-compost and AMF maintained to help with phosphorus absorption. / May 2007