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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
451

Building Integrated Water Efficiency Strategies that Generate Energy and Enhance Human Thermal Comfort

Selim, Kareem Hassan January 2014 (has links)
Building integrated water efficiency strategies can generate energy or reduce the energy consumption of the building. Solar and wind are two natural forces that are commonly used to provide energy to buildings today; water, on the other hand, is usually ushered off site and not utilized to its full potential. The question is how to find a way to reduce the energy used to get the water needed for the building, because water is an important aspect to care about and save. This will require several methods and strategies in order to find the best and most efficient way of doing this. This thesis is proposing a smarter way of utilizing one of earth's most precious resources as a guideline for the designer to conserve energy by using a water harvesting system, grey water system and reuse, water use reduction, water heating and cooling. Concentrating more on generating energy or reducing energy consumption using water by fuel cells, solar water heater, photovoltaic thermal and algae. Finally, the proposed method is to generate energy using algae, while growing it to the building's façade facing south. Algae panels use water and sunlight to grow, then are harvested in the building to generate enough energy to power it. Algae is the most known source of energy now and only used for industrial purposes, however applying it to a research building called Engineering Innovative building got 134 feet south façade, will be a huge source of energy to power it up. It also can be used for educational purposes to study.
452

A cytological investigation of cell division in the filamentous green alga, Sirogonium melanosporum (Rahdhawa) Transeau

Waer, Richard Dennis, 1939- January 1965 (has links)
No description available.
453

Characterization of twenty-one mutants resistant to high levels of streptomycin in Chlamydomonas reinhardi

Horn, Nancy Ann, 1949- January 1977 (has links)
No description available.
454

An ecological study of the viable airborne algae of the Tucson and the Santa Catalina Mountain areas

Luty, Elanny Thomas, 1938- January 1964 (has links)
No description available.
455

Fatty Acids as Dietary Tracers at the Base of Benthic Food Webs

Kelly, Jennifer R 21 July 2011 (has links)
Fatty acid (FA) analysis is a powerful ecological tool for examining trophic relationships among marine organisms. Its application in benthic food webs may be limited because many benthic organisms consume a highly mixed diet, and FA metabolism of benthic invertebrates may obscure dietary markers. This thesis examines the use of FA as dietary tracers for studying the diets of benthic invertebrates and the fate of primary production in rocky subtidal food webs. In Chapter 2, I review the use of FA for studying benthic marine food webs, and suggest that field studies using FA analysis should also include data from controlled feeding experiments, gut contents, or stable isotope analysis to provide more reliable results. In Chapter 3, I compare FA composition among sea urchins fed four natural algal diets in a controlled feeding study. These sea urchins substantially modified their dietary FA but differed in their overall FA composition according to diet. In Chapter 4, I use FA to trace the invasive alga Codium fragile ssp. fragile and the native kelp Saccharina longicruris through two trophic transfers in an experimental food web. Substantial signal attenuation occurred with each trophic transfer, suggesting that FA analysis may be of limited use for tracing benthic primary producers in field studies. In Chapter 5, I use FA in conjunction with stable isotope analysis and gut contents analysis to investigate the contribution of detrital kelp to the diet of sea urchins in habitats adjacent to kelp beds. FA analysis was unable to distinguish among sea urchins at different distances from the kelp bed, but the results of all analyses indicated that the availability of kelp detritus declines with distance from the kelp bed, and that sea urchins in low-productivity habitats rely on both kelp detritus and benthic diatoms. In Chapter 6, I summarize the overall findings and suggest experimental and statistical methods to address some of the problems associated with using FA analysis to study trophic relationships in benthic food webs.
456

Mercury uptake and dynamics in sea ice algae, phytoplankton and grazing copepods from a Beaufort Sea Arctic marine food web

Burt, Alexis Emelia 21 September 2012 (has links)
Mercury (Hg) is one of the primary contaminants of concern in the Arctic marine ecosystem. Methyl Hg (MeHg) is known to biomagnify in food webs. During the International Polar Year - Circumpolar Flaw Lead study, sea ice, seawater, bottom ice algae, phytoplankton and the herbivorous copepods were collected from the Amundsen Gulf to test whether ice algae and phytoplankton assimilate Hg from their habitat, and whether Hg bioaccumulates from the seawater to the primary consumers. Sea ice algae were found to accumulate Hg primarily from the bulk bottom ice, and the sea ice algae bloom depleted Hg stored within the bottom section of the ice. Furthermore, biodilution of Hg was observed to occur in sea ice algae. Higher concentrations of Hg were also found in phytoplankton and in grazing copepods. A positive correlation between MeHg and trophic level suggests the occurrence of MeHg biomagnification even at these low trophic positions.
457

Biotransformation of 2,4,6-trinitrotoluene (TNT) by the cyanobacterium anabaena spiroides

Jackson, Gardner H. 08 1900 (has links)
No description available.
458

The allometry of algal growth and respiration

Tang, Evonne P. Y. (Evonne Pui Yue) January 1995 (has links)
A knowledge of the allometry of algal growth and respiration can be applied to biomass-size distribution models which are in turn used in the prediction of fish yield and ecosystem studies. However, the scaling exponents reported in the literature are variable. This variation may be attributed to differences in the expression of cell size and phylogeny, but could also reflect small sample size which underlie most published regressions. This thesis establishes the allometry of algal growth and respiration based on a larger sample taken from the literature, and evaluates the effects of differences in gross taxonomy and in the expression of cell size on these relations. Allometric relations based on cell carbon appear more consistent with relations from other taxa than those based on cell volume, reflecting the size dependence of algal elemental composition which does not occur in most other taxa. The allometric relation of algal respiration (R in pl O$ rm sb2 cdot cell sp{-1} cdot hr sp{-1})$ was found to be R = 0.030C$ sp{0.93}$ where C is cell carbon content in pg C$ rm cdot cell sp{-1}$. Among the 6 divisions studied (Chlorophyta, Chrysophyta, Cyanophyta, Euglenophyta, Pyrrophyta, Rhodophyta), chlorophytes, euglenophytes and rhodophytes exhibited different respiration-size relation but separate relations were not developed for each of those groups due to patterns in residuals or small sample sizes. The specific rate of algal growth ($ mu$ in divisions$ cdot$day$ sp{-1}$) also depends on size and it is found to be $ mu$ = 3.45C$ sp{-0.21}.$ All taxa studied here (Chlorophyta, Chrysophyta, Pyrrophyta) have similar scaling exponents for growth but Pyrrophyta have significantly lower growth rates than other algae of similar size.
459

Composition and function of the pyrenoids of algal chloroplasts

McKay, R. Michael L. (Robert Michael Lee) January 1991 (has links)
Immunocytochemical analyses have demonstrated that the Calvin cycle enzyme ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) is predominantly localized in the pyrenoid region of chloroplasts of evolutionarily diverse algae. That Rubisco remains pyrenoid-localized at photosynthetically-saturating irradiance in the green alga Chlorella pyrenoidosa indicates a catalytic, rather than storage function for pyrenoid-localized Rubisco. This is further supported by the immunolocalization of Rubisco activase to the pyrenoids of two species of green algae. The exclusion of phosphoribulokinase from the pyrenoids of a red and a green alga indicates that pyrenoids do not possess the full complement of Calvin cycle enzymes. / Thylakoid lamellae traverse the pyrenoids of many algae. The absence of light-harvesting phycoerythrin and of photosystem (PS) II activity, but not PSI activity, from the intrapyrenoid thylakoids of the red alga Porphyridium cruentum indicates a structural and functional heterogeneity between these lamellae and those located in the chloroplast stroma. In contrast, the intrapyrenoid thylakoids of cryptomonads, algae whose chloroplast is thought to have evolved from red algae, possess both PSI and PSII protein complexes. These results are discussed with reference to Rubisco being mainly pyrenoid-localized in these algae.
460

Mercury uptake and dynamics in sea ice algae, phytoplankton and grazing copepods from a Beaufort Sea Arctic marine food web

Burt, Alexis Emelia 21 September 2012 (has links)
Mercury (Hg) is one of the primary contaminants of concern in the Arctic marine ecosystem. Methyl Hg (MeHg) is known to biomagnify in food webs. During the International Polar Year - Circumpolar Flaw Lead study, sea ice, seawater, bottom ice algae, phytoplankton and the herbivorous copepods were collected from the Amundsen Gulf to test whether ice algae and phytoplankton assimilate Hg from their habitat, and whether Hg bioaccumulates from the seawater to the primary consumers. Sea ice algae were found to accumulate Hg primarily from the bulk bottom ice, and the sea ice algae bloom depleted Hg stored within the bottom section of the ice. Furthermore, biodilution of Hg was observed to occur in sea ice algae. Higher concentrations of Hg were also found in phytoplankton and in grazing copepods. A positive correlation between MeHg and trophic level suggests the occurrence of MeHg biomagnification even at these low trophic positions.

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