To improve photovoltaic system efficiencies, concentrating spectral dividers are used to separate solar light, and to focus each spectral portion onto photovoltaic cells of matching spectral response. In this investigation, an optical analysis is developed to study the feasibility for use of a Fresnel half-lens as a concentrating spectral divider. To facilitate the analysis, an existing curved-base linear Fresnel lens ray-trace model has been modified and expanded. Solar limb-darkening has been incorporated into the theory by means of a digitized sun model. The lens model allows for variation of lens geometrical characteristics. Transmission losses due to Fresnel reflection and bulk absorption are taken into account. The distribution of the concentrated solar flux in the lens image plane is modeled such that spectral regions may be examined separately. Concentration ratio profiles are used to derive and evaluate a quantity of spectral separation.A computer program has been used to generate data, based on the theoretical model, for example lenses. The spectral separation, transmission and concentration properties for each example lens have been systematically studied with respect to lens geometry. The effects of solar limb-darkening are determined by comparison with the data from a model that assumes a uniform solar source. Results of the study are discussed in detail.Ball State UniversityMuncie, IN 47306

The synthesis of 7-amino-2-methylquinoline-5-8-dione (17) and 7-amino-3-methylquinoline-5,8-dione (157) are described.7-Amino-3-methylquinoline-5,8-dione (157) was prepared via alkaline hydrolysis of 7-acetamido-3-methylquinoline5,8-dione (149). 7-Acetamido-3-methylquinoline-5,8-dione (149) was prepared via the Diels-Alder reaction of 2-acetamido-6-bromo-1,4-benzoquinone (6) and 2-methyl-2propenal dimethylhydrazone (110).7-Amino-2-methylquinoline-5,8-dione (17) was prepared by the acid hydrolysis of 7-(triphenylphosphineimino)-2methylquinoline-5,8-dione (16). 7-(Triphenylphosphineimino)2-methylquinoline-5,8-dione (16) was prepared by tie treatment of 7-azido-2-methylquinoline-5,3-dione (15) with triphenylphosphine. 7-Azido-2-methylquinoline-5,8-dione (15) was prepared by treating 7-bromo-2-methylquinoline-5,8-dione (14) with sodium azide. The structures of the new compounds 15, 16, 17,149 and 157 were confirmed using MP, NMR, IR, MS and HRMS data. NMR, IR and MS data for known compounds 10, 11, 12, 13 and 14 are included for future reference.Ball State UniversityMuncie, IN 47306

This study was undertaken to determine where adolescents obtain their health care. A survey form was sent to four high schools in this state which reported urban, suburban, and rural populations. This questionnaire contained 18 items designed to determine demographic statistics about the study population as well as to identify their source of health care. Results from the 569 respondents were tabulated and analyzed. Most of this 15-16 year old adolescent group considered their doctor to be a family doctor. It was to a family doctor that most adolescents turned to for medical care. Other physicians and health care providers delivered some of the care but usually the family physician was the most frequent care giver. Adolescents are felt to be an underserved group of patients and the results of this study could be used to channel more efforts toward delivery of their health care. Conclusions drawn here reveal that family physicians do provide most of an adolescent's care.Ball State UniversityMuncie, IN 47306

This creative project investigates a method for translating a run-length encoded data file of letterforms into bit mapped images. Each letterform is broken (cracked) into primitive strokes. Each primitive stroke is represented by equally spaced runlength spline points within a 72 unit counting system. The strokes are ordered from left to right, allowing a direct scan-line conversion using an on-off character fill. Most commercial letterforms are stored in an outline format. Outline letterfomrs must be converted to vector edges, and then quick sorted into two dimensional arrays of edges for scan-line conversion (no overlapping outlines are allowed). The author's method stores primitives in a left to right ordered format that eliminates the sorting routine.In order to display the letterforms as a body of text, an interpreted description language was developed. The language command structure is embedded in the text file and interpreted at run time. The language controlls the sizing and placement of letterforms at five levels. The page attributes controlls the placement of page margins, column margins, windows, headers, footers, etc. The Paragraph attributes controlles first word indents, paragraph indents, widow lines, etc. The line attributes controlles the text line length, inter word and character spacing, line leading, additional line indents, type of line justification and hyphenation, etc. No attributes were established at the word level. The character attributes controlles the type size, type style, degree of slant (poor man's italic), expansion or contraction, etc.Ball State UniversityMuncie, IN 47306

The purpose of this study was to optimize and investigate crown ether analysis by using a mass spectrometer equipped with a direct insertion solids probe. The typical aliphatic and aromatic crowm ethers, 18-crown-6 and dibenzo-18-crown-6 were chosen for the study. The crown ether samples were prepared by miximg with the reagents (some inorganic and organic salts and glycine) or being supported on the support materials (diatomite and glass supports) in a 1:10 ratio by weight as the samples for testing. The pure crown ethers and their mixtures were tested by the programmed temperature direct insertion probe mass spectrometer. The effects of the reagents and support materials on the peak maximum temperature (Tm) and the spectra of the crown ethers were studied. The results Tm of the crown ethers to increase significantly, and glycine and ammonium salts interfered the spectra of the crown ethers. The effect of sample size and "concentration" on Tm of the crowns also was investigated. The bigger sample size caused the Tm to be higher. No significant effect of the "concentration" on Tm was observed. It was concluded that tha smaller sample size provided better spectra with less interfererences and that some thermally stable reagents or support materials could be used to facilitate the sampling of crown ethers. More detailed study of the effects of iodides on Tm was recommended. In addition, more detailed investigation of the approach of using a CI source without reagent gases is needed. Switching to the CI configuration appears to be a simple and effective method for providing complementary information about the molecules.Ball State UniversityMuncie, IN 47306

Mechanical Alloying is a manufacturing process that produces alloys by cold welding of powders. Usually, a vial containing both the powder and steel balls is agitated. Due to impact between the balls and balls and the vial, the powder is mechanically deformed, crushed, and mixed at nano-scales. In this thesis, a numerical model is developed to simulate the dynamics of the vial and the grinding balls of the SPEX 8000 ball milling device, a standardized equipment in both industrial and academic investigations of ball milling. The numerical model is based on the Event Driven Method, typically used to model granular flows. The method implemented is more efficient than the discrete element method used previously to study ball milling dynamics. The numerical tool obtained is useful for scale-up and optimization of mechanical alloying of various materials. An optimization study is presented for the SPEX 8000.

There is no abstract available for this dissertation.

An experimental ball-milling study was performed to compare the deagglomeration behavior and the evolution of the particle size distribution with increasing milling time of two relatively coarse WC powders used for the production of cemented carbide cutting tools. The WC-powders were found to have distinctly different particle size distributions and particle morphologies prior to milling. Lab-scale WC samples were made using a range of different process parameters and milling times. These were then analysed by means of microscopy, laser light scattering, gas adsorption BET analysis and X-ray powder diffraction, XRD, to attain particle size distribution, specific surface area and a mean crystal size, respectively. The results suggested a linear relation between log(particle size) and log(milling time) between 10 and 80 hours milling. The viscosity was shown to have a minor effect on the milling efficiency. Both the number of collisions of milling balls per unit time as well as the kinetic energy of the milling ball affected the size reduction; more collisions or higher energy resulted in a higher milling efficiency. The evaluation of the effect of the process parameters on milling efficiency was facilitated by the use of simple scaling factors. For example, all milling curves for samples with different WC amounts coincided when rescaling the milling time using a scaling factor based on the weight of the WC and milling balls. The same scaling factor could be used with success for rescaling the results from different trials obtained with laser light scattering, gas adsorption and XRD. The results of this work are useful for future work on modeling of the milling process which should lead to more accurate predictions of the outcome of milling unit operations.

A widespread problem in the housing of captive animals is the occurrence and development of abnormal behaviors. In the pig breeding industry the abnormal behaviors causing the biggest welfare problems are stereotypies such as tail-biting, ear-biting, equipment-biting and belly-nosing. In this study a rope and an activation ball were tested as curative treatments to reduce the performance of these stereotypies by inducing the underlying innate behaviors. A total of 141 pigs spread over 18 pens were used as test-subjects. They were divided into three groups which were introduced to one of the two enrichments or no enrichment at all. Both the enrichments contained characteristics which mostly targeted exploratory and foraging needs and, if functional, were thought to mainly have an effect on tail-biting, ear-biting and equipment-biting. The pigs were observed both at initial contact with the enrichments and after having familiarized with them for three days, and the amount of registered enrichment interaction and performed stereotypies were used to evaluate the effect of the enrichment objects. In both enrichment treatments the enrichments occupied the pigs both on day one and after three days. The presence of equipment-biting was successfully reduced on both day one and day three while the presence of tail-biting and ear-biting only were initially reduced. No effect was found on belly-nosing in either enrichment treatment. This suggests that both enrichments are functional over time and efficient in reducing some types of harmful social behaviors. However, belly-nosing would need to be targeted with a different kind of object.

No description available.