Development Of A Luminescent Polymer Sensor Array For The Discrimination Of Carboxylates And Further Improvements In A Solvent Programmable Polymer

This thesis summarizes the work performed on two stimuli responsive polymer projects. The first project used a lanthanide based luminescent polymer to create a sensor array for carboxylate analytes. Initial attempts incorporated molecular imprinting as a means to incorporate unique selectivity into the polymer by introducing acetate, benzoate, and phenylacetate as templates prior to polymerization. This process was successful at creating unique sensing elements for the array, but the polymers lacked the specific selectivity typically seen in molecularly imprinted polymers (MIPs). Instead, a ligand displacement mechanism that relied on multiple sensors with different labile anion ligands directly complexed with the europium center was utilized. This system resulted in unique response patterns with the introduction of carboxylate analytes, which were characterized using linear discriminant analysis (LDA). The second project re-examined our group’s theory about our solvent programmable polymer (SPP). Specifically, previous evidence suggested that the SPPs undergo a conformational change when heated and then cooled in a nonpolar solvent due to a dimerization between the carboxylate functional groups. To expand the utility of this unique polymer, synthetic modifications were made to the functional monomer in order to replace the ring opened metathesis polymerization (ROMP) with free radical polymerization

Do Borders Matter? Soviet economic Reform after the Coup

macroeconomics, Soviet, borders, economic reform

A technique for the direct measurement of transport with application to the Straits of Florida

A method is described by which the volume transport per unit width of a water column is obtained from measurements of the run time, depth, and horizontal d efl ection of a freely falling instrument. Measurements of the north-south component of transport in the Straits of Florida using this technique gave 35.5 ± 1.2 x 106 m3/sec on August 16 and 17, 1964. The surface currents and east-west components of transport are also given

Effects of Nutrient Availability and Other Elevational Changes on Bromeliad Populations and Their Invertebrate Communities in a Humid Tropical Forest in Puerto Rico

Nutrient inputs into tank bromeliads were studied in relation to growth and productivity, and the abundance, diversity and biomass of their animal inhabitants, in three forest types along an elevational gradient. Concentrations of phosphorus, potassium and calcium in canopy-derived debris, and nitrogen and phosphorus in phytotelm water, declined with increasing elevation. Dwarf forest bromeliads contained the smallest amounts of debris/plant and lowest concentrations of nutrients in plant tissue. Their leaf turnover rate and productivity were highest and, because of high plant density, they comprised 12.8and contained 3.3 t ha -1 of water. Annual nutrient budgets indicated that these microcosms were nutrient-abundant and accumulated \u3c 5dwarf forest, where accumulation was c. 25biomass/plant peaked in the intermediate elevation forest, and were positively correlated with the debris content/bromeliad across all forest types. Animal species richness showed a significant mid-elevational peak, whereas abundance was independent of species richness and debris quantities, and declined with elevation as forest net primary productivity declined. The unimodal pattern of species richness was not correlated with nutrient concentrations, and relationships among faunal abundance, species richness, nutrient inputs and environment are too complex to warrant simple generalizations about nutrient resources and diversity, even in apparently simple microhabitats

Influence of springtime phenology on the ratio of soil respiration to total ecosystem respiration in a mixed temperate forest

Total ecosystem (Reco) and soil (Rs) respiration are important CO2 fluxes in the carbon balance of forests. Typically Rs accounts for between 30-80% of Reco, although variation in this ratio has been shown to occur, particularly at seasonal time scales. The objective of this study was to relate changes in Rs/Reco ratio to changing springtime phenological conditions in forest ecosystems. We used one year (2003) of automated and twelve years (1995-2006) of manual chamber-based measurements of Rs. Reco was determined using tower-based eddy covariance measurements for an oak-dominated mixed temperate forest at Harvard Forest, Petersham, MA, USA. Phenological data were obtained from field observations and the JRC fAPAR remote sensing product. The automated and eddy covariance data showed that springtime phenological events do influence the ratio of soil to total ecosystem respiration. During canopy development, Reco rose strongly, mainly the aboveground component, due to the formation of an increasing amount of respiring leaf tissue. An increase in Rs was observed after most of the canopy development, which is probably the consequence of a shift in allocation of photosynthate products from above- to belowground. This hypothesized allocation shift was also confirmed by the results of the twelve year manual chamber-based measurements

Economic Feasibility of Ethanol Production from Sweet Sorghum Juice in Texas

The economic feasibility of producing ethanol from sweet sorghum juice is projected using Monte Carlo simulation models to estimate the price ethanol plants will likely have to pay for sweet sorghum and the uncertain returns for ethanol plants. Ethanol plants in high yielding regions will likely generate returns on assets of 11%-12% and in low yield areas the returns on assets will be less than 10%.Sweet Sorghum, Ethanol, Monte Carlo Simulation, Agribusiness, Agricultural Finance, Crop Production/Industries, Farm Management, Risk and Uncertainty, D20 G10 D81 C15,