Interest in biodiesel has piqued with advent of stringent emissions regulations. Biodiesel is a viable substitute for petroleum diesel because biodiesel produces significantly lower particulate and soot emissions relative to petroleum diesel. Higher nitric oxide (NO) emissions for biodiesel, however, are of primary concern in biodiesel-fueled engines. Search for an in-cylinder technique to reduce NO emissions for biodiesel has motivated studies to gain an improved understanding of fundamental factors that drive increase in NO emissions with biodiesel. Potential factors include fuel-bound oxygen, fuel-bound nitrogen and post-flame gas temperature. The role of fuel-bound oxygen however is debated in the literature. The research objective of this study is to computationally determine if biodiesel and petroleum diesel yield equivalent concentrations of NO with the same oxygen equivalence ratio in a 0-D homogeneous reactor, to explain the role of fuel-bound oxygen in biodiesel on increases in NO emissions with biodiesel. The results from this study indicate that the biodiesel surrogate yields higher NO emissions than the n-heptane because of its lower oxygen consumption efficiency. The lower oxygen consumption efficiency for biodiesel is likely because of the slower decomposition of the individual components and the blending ratios of the biodiesel surrogate blend. The relative differences in combustion efficiency of individual components of the biodiesel blend suggest this conclusion. The more efficient burning of the methyl esters relative to the n-heptane in biodiesel surrogate perhaps indicates the favorable role of fuel-bound oxygen in the fuel’s combustion. The low utilization of oxygen by the biodiesel surrogate could not be explained in this study. The dominance of NO2 H ↔ NO OH and N NO ↔ N2 O mechanisms during biodiesel combustion however explain the high NO emissions for the biodiesel surrogate relative to the n-heptane. The biodiesel may yield lower NO emissions than the petroleum diesel if the blending ratios for the biodiesel are adjusted such that combustion efficiency of biodiesel and petroleum diesel is same or the NO2 H ↔ NO OH and N NO ↔ N2 O mechanisms are suppressed during biodiesel combustion.

In recent years, the development and use of biofuels have received considerable attention due to the high demand for environmentally acceptable (green) fuels. Most of the recent studies have looked at the processes of converting vegetable oils into biodiesel. It is well known vegetable oil to biodiesel conversion involves many processes including transesterification, which makes biodiesel costly and time-consuming to produce. In this study, the effects of blending high-viscosity fresh and used corn oils with low-viscosity diesel and jet fuel mixed with butanol and ethanol were studied. Several corn oil-based blends were formulated and characterized to understand the effect of composition on viscosity, fuel stability and energy content. The formulated corn oil blends were combusted in a 30 kW modified combustion chamber to determine the corresponding NOx and CO emission levels, along with CO₂ levels. Used corn oil was made by simply heating fresh corn oil for a fixed period of time (about 44 hours), and was characterized by quantifying its total polar material (TPM), iodine value, free fatty acid content, and peroxide value. The combustion experiments were conducted at a constant heat output of 68,620 kJ/hr (19 kW), to observe and study the effects of equivalence ratio, swirl number, and fuel composition on emissions. Used corn oil blends exhibited better combustion performance than fresh corn oil blends, due in part to the higher unsaturation levels in fresh corn oil. NOx emissions for used corn oil increased with swirl number. Among all the blends, the one with the higher amount of diesel (lower amount of corn oil) showed higher NOx emissions. The blend with fresh corn oil showed decreasing NOx with increasing equivalence ratio at swirl number 1.4. All blends showed generally decreasing CO trends at both swirl numbers at very lean conditions. The diesel fuel component as well as the alcohols in the blends were also important in the production of pollutants. Compared to the diesel-based blends mixed with used corn oil, butanol, and ethanol, the jet fuel-based blends showed higher NOx levels and lower CO levels at both swirl numbers.

A mixture experiment is an experiments in which the q-ingredients are nonnegative and subject to the simplex restriction on the (q-1)-dimentional probability simplex. In this work , we investigate the robust A-optimal designs for mixture experiments with uncertainty on the linear, quadratic models considered by Scheffe' (1958). In Chan (2000), a review on the optimal designs including A-optimal designs are presented for each of the Scheffe's linear and quadratic models. We will use these results to find the robust A-optimal design for the linear and quadratic models under some robust A-criteria. It is shown with the two types of robust A-criteria defined here, there exists a convex combination of the individual A-optimal designs for linear and quadratic models respectively to be robust A-optimal. In the end, we compare efficiencies of these optimal designs with respect to different A-criteria.

Recent years have witnessed a great deal of interest in the design and synthesis of small molecules, which can mimic complex carbohydrates of vital importance in various life processes. Carbasugars constitute one such class of molecules among several others, in which ring oxygen of sugar is replaced by a methylene unit. Several approaches have been reported in the literature for the synthesis of carbasugars emanating both from carbohydrate and non-carbohydrate sources. While the carbohydrate-based approaches require extensive prote'ction-deprotection maneuver, the non-carbohydrate-based approaches generally have problems of diastereoselection and introduction of chirality. In the context of synthesis of carbasugars, we envisaged that a suitable derivative of i bicyclo[2.2.1]heptane (norbornyl system), could serve as a carbasugar equivalent provided the inherent cyclohexane ring could be disengaged through a tactical cleavage of C1-C7 or C4-C7 bonds. In the present thesis entitled "Synthesis of carbasugars and other structurally related motifs", we have established the carbasugar-norbornyl system equivalence by using 7-* oxobicyclo[2.2.1]hept~5-en-2~yl acetate as precursor . While the tactical cleavage of C1-C7 bond was employed in the synthesis of carbasugars, the C4-G7 bond cleavage provided access to a new class of carbasugars i.e. "confused" carbasugars* The quest for stronger and specific inhibitors of glycosidases led us to synthesize a diverse array of polyoxygenated compounds in this new family of carbasugars. The thesis has been organized under five main sections: I. Introduction, II. Results & Discussion, III. Experimental, IV. Spectra, and V. References where we have narrated our I synthetic efforts with suitable literature citations.

Electronic data capture technologies, such as interactive voice response (IVR) systems, are emerging as important alternatives for collecting self-reported data. The purpose of this research was to assess the measurement equivalence between the original paper-based versions and the adapted interactive voice response (IVR) versions of the EQ-5D and the QLQ-C30. Furthermore, we examined the test-retest reliability of two consecutive administrations of the IVR versions of the EQ-5D and the QLQ-C30. The comparison of the paper and IVR versions of the EQ-5D was conducted utilizing a crossover design with subjects randomly assigned to one of two assessment orders: 1) paper then IVR or 2) IVR then paper. A convenience sample of in-treatment outpatient cancer clinic patients (n=139) were asked to complete each assessment two days apart. For the test-retest component, outpatient cancer clinic patients (n=127) were asked to complete the IVR-based EQ-5D twice, two days apart. The analyses tested for mean differences (paired t-test) and test-retest reliability (ICC).In the crossover analysis, ten of the fifteen mean differences analyzed for the scales and items of the QLQ-C30 were within the equivalence interval set a priori. The ICCs for the scales and items of the QLQ-C30 ranged from 0.698 to 0.899. Two of the items, insomnia and appetite loss, did not meet our threshold of being statistically different from an ICC of 0.70. The EQ-5D index score means were equivalent between paper and IVR, however the EQ VAS score differences were not wholly contained in the equivalence interval. The ICCs were above 0.890 for the index and the EQ VAS. In the test-retest analysis, the ICCs for the nine multi-item scales for the QLQ-C30 were all above 0.69, ranging from 0.698 to 0.891. Ten of the fifteen mean differences analyzed were within the equivalence interval set a priori. For the EQ-5D, the mean differences were wholly contained within the equivalence intervals for both the index and the EQ VAS and the ICCs were significantly different from 0.70. Overall, the IVR version of the questionnaires provided psychometrically equivalent results to those obtained on the original paper version and showed good stability over time.

The subject of Master`s work – Lithuanian Phraseological Units With Component „eye“ Equivalents In English And Russian Languages. 518 examples of phraseological units with component „eye“, are picked out from Lithuanian, English and Russian Dictionaries of Phraseology. These tasks are set in Master`s work: • To consider an academic material, which deals with the subject. • To pick out phraseological units with component „eye“ from Lithuanian, English and Russian Dictionaries of Phraseology. • To group phraseological units into thematic groups according to their meanings. • To do contrastive analysis of fraseological units according to their stucture and stylistic. • To group phraseological thematic groups according to their equivalence in Lithuanian, English and Russian languages. In the preface of Master`s work, the tasks of the subject are stated, academic material is analysed. In the main part of Master`s work, Lithuanian, English and Russian phraseological units with component „eye“, are contrasted and analysed according to these positions: meaning, structure, stylistic, equivalence. All phraseological units with component „eye“ in Lithuanian, English and Russian languages are grouped in 4 thematic groups according to their meaning: motion, visual, physical, psychoemotional. Lithuanian, English and Russian phraseological units are classified from the point of view of their structure and stilistic. According to their equivalents in Lithuanian, English and Russian... [to full text]

In this thesis we discuss how to find equivalent representations of polynomial functions over the ring of integers modulo a power of a prime. Specifically, we look for lower degree representations and representations with fewer variables for which important applications in electrical and computer engineering exist. We present several algorithms for finding these compact formulations.

This thesis proposed two nonparametric statistical tests, based on the Kolmogorov-Smirnov distance and L2 mallows disatnce. To implement the proposed tests, nonparametric bootstrap method is employed to approximate the distributions of the test statistics to construct the corresponding bootstrap confidence interval procedures. Monte-Carlo simulations are performed to investigate the actual type I error of the proposed bootstrap procedures. It is found that the type I error of the bootstrap BC confidence interval procedure is close to the nominal level when censoring is not heavy and the boosttrap percentile confidence interval procedure works well when Kolmogorov-Smirnov distance is used to characterize the equivalence. When the data is heavily censored, the procedures based on the Kolmogorov-Smirnov distance have very conservative type I errors, while the procedures based on the Mallows distance are very liberal. / Thesis (Ph.D, Mathematics & Statistics) -- Queen's University, 2007-08-01 10:43:32.345

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