Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 4 uppsatser.

Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第15346号 / 工博第3225号 / 新制||工||1485(附属図書館) / 27824 / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 伊藤 禎彦, 教授 津野 洋, 教授 田中 宏明 / 学位規則第4条第1項該当

Master of Science / Department of Animal Sciences and Industry / Dale A. Blasi / Effects of nucleotides (NA) (PSB Complex; DSS Global, Chicago, IL) with corn germ meal (CGM) or dried corn distillers grains (DDG) on growth performance, digestibility, in vitro ruminal gas production, and mucosal immunity were analyzed in 4 experiments. In Exp. 1, 213 crossbred heifers (BW= 262 ± 67.4 kg) were used in a complete block design with a 3 x 2 factorial arrangement of treatments to determine the net energy values of CGM in comparison to DDG and the effects of NA at three inclusion levels (0, 2, and 4 g) during an 84-d receiving period. Pens were randomly assigned to one of six treatments: 1) CGM with no NA (CGM0), 2) CGM with 2 g/heifer daily NA (CGM2), 3) CGM with 4 g/heifer daily NA (CGM4), 4) DDG with no NA (DDG0), 5) DDG with 2 g/heifer daily NA (DDG2), and 6) DDG with 4 g/heifer daily NA (DDG4). There were no significant effects of NA or the type of corn byproduct on growth performance (P ≥ 0.15). Exp. 2, was conducted to determine the performance and mucosal immunity effects of NA using 240 crossbred heifers (BW= 268 ± 34.1 kg). Pens were randomly assigned to three treatments which consisted of diets 4, 5 and 6 from Exp. 1. Calves were blocked by weight and assigned to a pen for 56-d. There were no significant effects of NA on growth performance results (P ≥ 0.18). On d 28, fecal samples were collected from approximately 5 calves from each pen and analyzed for secretory IgA concentration. NA inclusion did not affect fecal IgA concentration (P = 0.15). Exp. 3, utilized 4 ruminally cannulated Holstein heifers in a 4 x 4 Latin square design. The four treatments included diets 1 and 4 from Exp. 1 along with those two diets supplemented with 3 g/heifer daily NA. Ruminal pH increased as NA was included (P < 0.05). Ammonia concentrations were greater for DDG than for CGM (P < 0.01). Ruminal propionate concentration was less in diets that contained NA (P < 0.05). DDG diets led to greater concentrations of butyrate, isobutyrate, isovalerate, and valerate in ruminal fluid than CGM diets (P < 0.01). Valerate concentrations were decreased by NA when included in DDG diets, but not when added to CGM diets (interaction, P < 0.01). Isovalerate concentrations were increased by NA when included in CGM diets, but not when added to DDG diets (interaction, P = 0.01). An in vitro study, Exp. 4, evaluated 24-h gas production effects of the 6 treatments in Exp. 1. Gas production was decreased linearly by the inclusion of NA in DDG diets, but it was unaffected by NA in CGM diets (interaction, P < 0.01). CGM can be included in receiving and growing diets at 24.5% on a DM basis in place of DDG while maintaining growth performance, digestibility, and gas production. There was no effect of NA on growth performance, digestibility, or mucosal immunity, but there was an effect on ruminal gas production and ruminal parameters. Further research is needed to determine the effects of NA on receiving and growing cattle.

Recent investigations have shown that engineered nanomaterials such as carbon nanotubes (CNTs) are a source and precursor for disinfection byproduct (DBP) formation. The aim of this study was to extend previous research of CNTs by investigating the potential for other classes of CNTs to generate disinfection byproducts (DBP) during chlorination. We examined particular types of CNTs with surface groups analogous to suspected model precursors for DBP formation.Specifically, we conducted experiments to determine the formation of haloacetic acids (HAAs) and N-nitrosodimethylamine (NDMA) via the chlorination of carbon nanotubes. Polymer coated CNTs generated the greatest total HAA concentration of up to 170 μg-HAA/mg-CNT. Results showed that the presence of surface oxide groups (e.g. surface carboxylic acid groups) promotes HAA formation. We observed a reasonably strong correlation between the extent of HAA formation and the concentration of surface oxygen on the CNT surface. Results also showed that CNTs behave similar to model precursors for di- and trichloroacetic acid formation (DCAA and TCAA, respectively). Nitrogen containing CNTs have been shown as source of N-nitrosodimethylamine (NDMA). Surprisingly, CS PEG, which does not contain N, produces NDMA when reacted with ethylenediamine (EDA). Ultimately, EDA is contributing N to CS PEG by sorbing to the CNT surface, which is the likely source of N for NDMA formation. At lower EDA concentrations, NDMA production is limited by available EDA. Conversely, at higher EDA concentrations, NDMA production is limited by available chlorine that is in competition with EDA and the CNT surface.

No description available.

Impact of Sludge Volume and Water Quality on DBPs in a Full-Scale Water Works The goal of this research was to determine the role of settled sludge on the formation of disinfection by-products in a full-scale water treatment plant. The occurrence of disinfection by-products in chlorinated drinking water has become a major concern to treatment facilities in their effort to comply with strict regulations set by the United States Environmental Protection Agency. Water samples were tested for trihalomethanes and haloacetic acids at both ends of the sedimentation process to evaluate formation over the length of the basin. Sludge volume and other important water quality parameters were also measured at the time of sample collection. Statistical analyses were used to analyze contributions from the sludge and to determine influential factors leading to disinfection by-product formation. The treatment plant incorporated chlorine dioxide into the treatment process seasonally, and effects were evaluated. Predictive models were developed from the data to be used under various treatment methods. The models created for trihalomethanes and haloacetic acids require measurements of chlorine dose, reaction time, total organic carbon, pH, water temperature, and sludge volume. The models performed well in predicting actual trihalomethane and haloacetic acid concentrations and could serve as a valuable tool in the control of disinfection by-products. DBP Formation Potential of Settled Sludge in a Full-Scale Water Treatment Facility It is still a common occurrence for water treatment facilities to store sludge in sedimentation basins for extended periods, rather than relying on mechanical collection equipment. The goal of this research was to characterize contributions from settled sludge to the formation of disinfection by-products (DBPs), and determine whether continuous removal is essential in the control of DBPs. Samples were taken from top and bottom sludge layers in the sedimentation basin and water was extracted either by draining or centrifugation. The water was analyzed for trihalomethanes and haloacetic acids and water quality measurements were recorded. Concentrations of both DBPs were very high in top-layer sludge; trihalomethanes ranged from 321.5 μg/L to 568 μg/L and haloacetic acids ranged from 74.6 μg/L to 409.8 μg/L. Evidence of biodegradation was observed in the bottom-layer sludge. The water samples were dosed with 4 mg/L chlorine, the United States Environmental Protection Agency's maximum residual disinfectant level, to determine if further DBP formation was possible. The extracted water from the bottom-layer sludge was shown to form high trihalomethane concentrations when chlorinated, and haloacetic acid concentrations were observed to increase when samples from the top-layer sludge were chlorinated. / Master of Science

In an effort to maintain compliance with current and future United States Environmental Protection Agency regulations governing haloacetic acids (HAAs) and trihalomethanes (THMs), the Blacksburg, Christiansburg, VPI (BCVPI) Water Authority in Radford, Virginia elected to eliminate prechlorination and replace it with preoxidation using chlorine dioxide (ClO2). Prior to full-scale application at the BCVPI Water Treatment Plant, jar testing was done to determine the effects of ClO2 on the formation of HAAs and THMs. Jar testing results showed a significant reduction in THM formation potential when 2.0 mg/L ClO2 was applied to raw water and chlorination was delayed. Chlorine dioxide doses less than 2.0 mg/L were statistically insignificant in the reduction of THM formation potentials below samples that were prechlorinated according to the BCVPI Water Treatment Plant's current practice. Likewise, ClO2 did not alter HAA formation potentials in such a way that statistical differences could be detected between ClO2 pretreatment and prechlorination, even at a dose of 2.0 mg/L ClO2. The two inorganic byproducts of ClO2, chlorite and chlorate, were also measured following jar tests. Chlorite concentrations increased with an increased ClO2 dose, but remained below 1.0 mg/L. Chlorate was formed in all jar-test samples. / Master of Science

Global energy requirements are heavily dependent on fossil fuels such as oil, coal, and natural gas. With the expectation of fossil fuels being exhausted in the future, novel strategies need to be discovered for alternative energy generation. Biofuels such as acetone, butanol, ethanol, and hydrogen gas are gaining interest as high value energy sources. These fuels can be produced by anaerobic clostridia as metabolic byproducts of fermentation. The capability to produce these biofuels has been widely studied using glucose or other common feedstocks. Biofuels from renewable and industrial waste feedstocks such as algae and cheese whey may have significant implications on the efficiency of biofuel production, where the price associated with feedstocks is considered a major bottleneck in biotechnology processes. Algae and cheese whey are both rich in organic nutrients and can be utilized by clostridia to produce not only biofuels, but also bioacids, which are considered fuel intermediate compounds. Additionally, understanding microbial communities both in the biosphere and within bioreactors can provide knowledge on microbial relationships and novel microbes, and provide knowledge to optimize engineered systems for biofuels and bioremediation strategies. In this study, a comprehensive investigation of the Logan City Wastewater Lagoon System at the microbial level was executed. Microalgae were utilized for the production of acetone, butanol, and ethanol using Clostridium saccharoperbutylacetonicum. High-throughput 454 pyrosequencing technology was utilized to understand the biogas-producing microbial consortium within an algal-fed anaerobic digester inoculated with lagoon sludge. This technology platform was also utilized to study the microbial diversity of a municipal waste remediating community while probing for clostridia capable of producing biofuels. Bioproduct producing clostridia from this system were isolated and employed using cheese whey as feedstock for the production of hydrogen, ethanol, acetic acid, butyric acid, and lactic acid. Integrating fundamental science with engineering strategies was demonstrated using this lagoon system. To optimize and fully understand and manage anaerobic microbial systems, an understanding of their phylogeny and their capabilities are vital for success at the industrial level for the production of high value bioproducts.

No description available.

京都大学 / 新制・課程博士 / 博士(工学) / 甲第23871号 / 工博第4958号 / 新制||工||1775(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 伊藤 禎彦, 教授 藤原 拓, 教授 越後 信哉 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM