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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.
91

Luminescence from d5 transition metal cation centres in plagioclase feldspars

Telfer, D. J. January 1975 (has links)
No description available.
92

Sustainable Residential Development in the Southwest

Donovan, Brian 09 May 2014 (has links)
Sustainable Built Environments Senior Capstone / The goal of this study is to address the issues of sustainable residential housing in the United States, more specifically Tucson and the arid climate of the southwest. Until recent years the lack of awareness for sustainable practices has not damaged society, but currently, mankind’s impacts on the planet are unprecedented. As we progress into the future, acknowledgment of this problem needs to be addressed with innovation and solutions to secure a guaranteed healthy future for humanity, the species that humanity coexists with, and planet Earth. This study examines the principles of development that best produce sustainability and addresses building form and material use, solar orientation and shading, and land-use efficiency and governmental policy. These aspects of development are examined in detail by contrasting a typical University of Arizona rental development and a development that was constructed with sustainable consciousness for Tucson’s local population. Sustainable residential development is an issue that must begin on large scale with government policy and lawmakers, and end with individual home residencies and educated personal environmental decisions. The study found that, while there are many different aspects of sustainable development that are influenced by countless variables, a sense of cooperation among all phases of construction is the most effective way to guarantee a smooth transition into a more sustainable future.
93

The attributes of green manuring as soil amendments for succeeding crops

Czajkowski, Henry Julian, 1924- January 1951 (has links)
No description available.
94

Considering a green roof substrate for northern climates

Yuristy, Greg 12 April 2013 (has links)
Twenty two substrates were developed and tested for two different green roof plant production methodologies. Growth rate analysis of Sedum sp. revealed distinct differences in performance of the mat substrates across a two year time frame with substrate water holding capacity (v/v) being a primary promoter of rapid mat coverage. Tray substrate analysis revealed numerous component options provided similar production speeds, with diverse and beneficial physical properties being described. Zebra and Quagga mussel shells proved to be a sustainable and beneficial component option for both mat and tray substrates. Further substrate component identification resulted in Biochar being investigated for its potential use in green roof media mixtures. The additions of incremental amounts of biochar into control substrates reduced bulk density by up to 20%, while simultaneously increasing volumetric water holding capacity to 54%, 12% greater than that of the control. Sedum plant growth in biochar revealed the lowest shoot dry weights resulting from no biochar additions. Substrate and plant water relationships were explored further with four substrates being planted with four diverse herbaceous and succulent plant communities. Substrate composition and plant community was observed to significantly affect dry down rates. / OMAFRA
95

The Transportation and Transformation of Energy Through Reversible Hydrogenation

CARRIER, ANDREW JAMES 30 August 2011 (has links)
Cycles of reversible hydrogenation reactions are important for at least two different energy-related applications: reversible chemical hydrogen storage and thermally regenerative fuel cells. Hydrogen fuel is a green alternative to conventional hydrocarbon fuels for transportation applications. This is because the combustion product of hydrogen is simply water, which is non-toxic and ubiquitous. Hydrogen is also an attractive fuel because of its high energy content; however, because it is a gas it has poor volumetric energy density. In Chapter 2, ionic liquids consisting of both cations and anions that can undergo reversible dehydrogenative aromatization were used to chemically store hydrogen. Cations investigated included pyridinium ions, which were easily hydrogenated but could not be regenerated through the dehydrogenation of piperidinium ions; and carbazole containing ammonium (whose synthesis failed) and imidazolium (which failed to hydrogenate) cations. The anions studied were heterocyclic carboxylates and sulfonates, these ions were observed to undergo both hydrogenation and dehydrogenation to various degrees when reacted in solution. However, as components of ionic liquids, they fail to react at a significant rate. The viscosity of the fluids was suspected to be hindering the diffusion of either hydrogen or the ions to or from the catalyst surface. In addition to using hydrogen as the primary source of energy in a vehicle, reversible hydrogenation can form the basis of a thermally regenerative fuel cell: a device that converts low grade vehicle waste heat, from a conventional engine, into electricity for the vehicles auxiliary power units. In Chapter 3, secondary benzylic alcohols, in particular 1-phenyl-1-propanol, were determined to be able to undergo dehydrogenation to the corresponding ketone rapidly and with extremely high selectivity over a palladium on silica catalyst. The dehydrogenation gave an initial rate of hydrogen evolution of 4.6 l of hydrogen per gram of palladium per minute and the enthalpy and entropy of the dehydrogenation is +56 kJ mol-1 and +117 J mol-1 K-1. This adsorbed energy can then be released as electricity in a fuel cell and be used to power auxiliary units in a vehicle without decreasing fuel economy. / Thesis (Ph.D, Chemistry) -- Queen's University, 2011-08-29 16:19:06.012
96

Immunocytochemical localization of photosystems I and II in the green alga Tetraselmis subcordiformis

Song, Xiu-Zhen January 1993 (has links)
The distribution of photosystem I (PS I) and photosystem II (PS II) in a primitive green alga Tetraselmis subcordiformis, which belongs to Prasinophyceae and does not have grana in its chloroplast, was studied by immunoelectron microscopy. Two PS I antibodies were used: one against a PS I component of maize, the other against the 60 and 62 KDa PS I reaction centre proteins of the cyanobacterium Synechococcus elongatus. Both antibodies showed that 76-78% of the labelling is on the appressed thylakoid membranes and only 22-24% is located on the unappressed membranes. Use of antiserum against cp-47 of PS II from S. elongatus also gives 76% of the labelling on appressed thylakoid membranes and 24% on unappressed thylakoid membranes. Cytochemical detection of PS I activity by the photooxidation of 3,3$ sp prime$-diaminobenzidine and of PS II activity by the photoreduction of distyryl nitroblue tetrazolium chloride also revealed that PS I and PS II activities exist on both types of thylakoid membranes. Therefore, our results indicate that the distribution of PS I and PS II in green algae may differ from that in higher plants.
97

Le Desir dans Moira de Julien Green.

Trahan, Victor January 1973 (has links)
No description available.
98

Mutagenesis of cytochrome b-559 in Chlamydomonas reinhardtii

Morais, Francisco Silverio January 2010 (has links)
No description available.
99

Biomarkers of flavonoid consumption for the evaluation of dietary burden

Copeland, Emma January 1996 (has links)
No description available.
100

The antigenotoxic effect of tea

McArdle, Nicholas J. January 2001 (has links)
No description available.

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