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Solder joints provide mechanical support, electrical and thermal interconnection between packaging levels in microelectronics assembly systems. Proper functioning of these interconnections and the reliability of the electronic packages depend largely on the mechanical properties of the solder joints. Lead free solders are common as interconnects in electronic packaging due to their relatively high melting point, attractive mechanical properties, thermal cycling reliability, and environment friendly chemical properties. However, environmental conditions, such as, operating temperature, aging temperature, and aging time significantly affect these properties due to the microstructural evolution of the solder that occurs during aging. Moreover, electronic devices, sometimes experience harsh environment applications including well drilling, geothermal energy, automotive power electronics, and aerospace engines, where solders are exposed to very high temperatures from T = 125-200 °C. Mechanical properties of lead free solders at elevated temperatures are limited. This research involves several projects to create a database of extreme high-temperature mechanical properties and the associated microstructural changes of several lead free solder alloys. In the first project, several SAC and SAC+X lead free solder alloys, recommended for high reliability applications have been chemically analyzed and then mechanically tested in order to determine the temperature dependent mechanical properties of these alloys. The alloys include SAC305, Ecolloy (SAC_R), Cyclomax (SAC_Q), and Innolot. The mechanical behavior of these alloys have been explored at several extreme high temperatures from 125 to 200 °C. For each of 4 elevated temperatures (T = 125, 150, 175, and 200 °C), tensile stress-strain tests were performed at three strain rates (SR = 0.001, 0.0001, and 0.00001 sec-1). For each alloy and testing temperature, the stress-strain curve shape and high temperature tensile properties (initial modulus, yield stress, and ultimate tensile strength) were measured and compared. In the second project, temperature dependent stress-strain behavior of SAC305, SAC_Q, and Innolot solders subjected to high temperature aging at 125 and 200 °C have been reported. Before testing, the solder uniaxial specimens were aged (preconditioned) at the extreme high temperature of either T = 125 °C or T = 200 °C. At each of these aging temperatures, several durations of aging were considered including 0, 1, 5, and 20 days. Stress-strain and creep tests were then performed on the aged specimens. Using the measured data, the evolutions of the stress-strain and creep behaviors were determined as a function of aging temperature and aging time. In third project, SAC305 and doped SAC solder alloys (SAC_Q and Innolot) recommended for high reliability applications have been chemically analyzed and then mechanically tested in order to determine the nine Anand parameters. Anand parameters were determined for SAC305 with both water quenched and reflowed microstructures. For SAC_Q and Innolot, only reflowed microstructures were explored to determine the Anand parameters. The nine Anand parameters were determined for each unique solder alloy from a set of uniaxial tensile tests performed at several strain rates and temperatures. Testing conditions included strain rates of 0.001, 0.0001, and 0.00001 (sec-1), and temperatures of 125, 150, 175, and 200 °C. In the fourth project, nanoindentation methods were utilized to explore the creep behavior, and aging effects of SAC305 solder joints at several extreme high testing temperatures from 125 to 200 °C. A special high temperature stage and test protocol was used within the nanoindentation system to carefully control the testing temperature, and make the measurements insensitive to thermal drift problems. Solder joints were extracted from 14 x 14 mm PBGA assemblies (0.8 mm ball pitch, 0.46 mm ball diameter). For all the experiments, only single grain solder joints were used to avoid introducing any unintentional variation from changes in the crystal orientation across the joint cross-section. After extraction, the single grain solder joints were subjected to various aging conditions. Nanoindentation testing was then performed on the aged specimens at four different testing temperatures (T = 125, 150, 175, and 200 °C). In order to understand creep response of the solder joints at different temperatures, a constant force at max indentation was applied for 900 sec while the creep displacements were monitored. With this approach, creep strain rate was measured as a function of both temperature and prior aging conditions. Nanoindentation pile-up effects, although insignificant at room temperature, were observed during high-temperature testing and corrections were made to limit their influence on the test results. The changes in mechanical behavior of solder alloys that occur during isothermal aging are a result of the evolution of microstructure. In the final project, the microstructural evolution of solder alloys were investigated for different aging conditions. In particular, aging was performed at T = 125, 150, and 175 °C for up to 20 days, and the topography of the microstructure of a fixed region was captured using the SEM system. This process generated several images of the microstructure as the aging progressed. These images were used to predict the microstructural evolution in SAC305 solder joints exposed to high temperature aging. Image analysis software was utilized to quantify microstructural changes (total area, number and average diameter of IMC particles, interparticle spacing etc.) with respect to aging time.

Bighead carp are characterized by many morphological and physiological adaptations that allow them to survive and grow in wide range of environmental conditions. However, information on how this species withstands environmental change is contradictory. To address this issue a set of experiments were conducted with the aim of determining the effects of two major environmental factors (temperature and oxygen saturation) on the growth of bighead carp under laboratory conditions. Small (S; 2.5±0.3g) and large (L; 5.7±0.5g) bighead carp juveniles were reared in temperatures that were gradually increased by 5°C. Overall, environmental factors significantly (P

Remote Sensing engages electromagnetic sensors to measure and monitor changes in the earth's surface and atmosphere. Remote Sensing Satellites are currently the fastest growing source of geographical area. Using data-mining techniques enables more opportunistic use of data banks of remote sensing satellite images. This thesis focuses on supervised and unsupervised classification, the two data mining techniques on the high resolution satellite Imagery from satellite IKONOS and satellite LANDSAT taken of the area around Kent State University, Ohio.The image was classified into ten distinct class: 1) Water, 2) Forested, 3) Agriculture, 4) Urban Development, 5) Vegetation1, 6) Vegetation2, 7) Vegetation3, 8) Vegetation4, 9) Grass, 10)Road. ERDAS Imagine was used in manipulating the images and creating the classification and analysis. The result obtained in form of accuracy helps to decide which image and classification technique is better to identify geographical patterns related to land use.

Comparative aspects of intake, digestibility, partitioning of digestion, energy requirement, energy utilization and water metabolism of kids and lambs have been made. Ad libitum intake and digestibility were determined in a series of short-term (4-6 weeks) experiments with forages ranging in N content from 6.6 to 26.8 g N/kg DM. The forage types were meadow hay, lucerne hay, prairie grass hay, ryegrass hay, ryegrass straw, cocksfoot straw and barley straw. No consistent differences between the animal species were found in the digestibility of DM, OM or NDF. However, as digestibility of the forage declined the ratio of DOMI (kids: lambs) increased indicating that with maintenance and sub maintenance forages kids were able to maintain a higher intake of digestible nutrients. The difference between the species was particularly evident below an OMD of approximately 0.6. A high and a low quality meadow hay (23.9 and 7.1 g N/kg DM, respectively) were offered during longer periods of 13-16 weeks. No differences in OMD occurred between the species on the high quality forage but with the low quality forage OMD in lambs gradually declined over the 16 week period whilst in kids OMD was maintained. This further emphasizes the ability of kids to obtain and maintain a higher input of digestible nutrients with low quality forage. Higher DOMI of forages with low N content appeared to be related to an ability of kids to maintain higher rumen NH₃-M concentrations. The quantitative partitioning of digestion in the stomachs (R), small intestine (SI) and large intestine (LI) of both species was examined in fistulated kids and lambs offered a high quality meadow hay at varying levels from maintenance to ad libitum. No differences were observed between the species in digestion of OM, NOF and NAN at any of the sites and regression equations relating nutrient flow (g/kgW⁰•⁷⁵/d) against nutrient intake were established. Approximately 0.60, 0.29 and 0.13 of the in vivo DM digestion (0.78) occurred in the R, SI and LI, respectively, in both species and approximately 0.94 and 0.06 of the in vivo NDF digestion (0.82) occurred in the R and LI of both species. There was a gain of total N (22%) and NAN (15%) in the R of both species whilst net disappearance of NAN in the SI and N in the LI was approximately 0.62 and 0.27, respectively. All these parameters varied slightly with level of feeding. The protein energy apparently absorbed in the small intestine per unit metabolizable energy intake (0.17) was low and not different between the species. A further group of kids and lambs were offered the same high quality meadow hay in a comparative slaughter experiment to compare the species for maintenance energy requirement (MEm) and efficiency of use of ME for growth (kg). There was no significant difference in MEm (0.44 vs 0.37 MJ ME/kgW⁰•⁷⁵/d in kids and lambs respectively) and in kg (0.28 ±0.067 vs 0.22 ±0.032) between the two animal species. The efficiency of use of absorbed amino acid for protein deposition was estimated by using the regression equations established for nutrient flow past the abomasum and ileum of fistulated kids and lambs to calculate absorbed amino acid in animals in the comparative slaughter trial. There was a marked difference in efficiency of use of protein for body protein deposition (0.59 ±0.097 vs 0.31 ±0.037; P0.05; kids vs lambs, respectively). The protein energy content of the energy gain was low (0.20) and not different between the species. Kids consistently consumed less water than did lambs (mean ratio of water intake - kids: lambs - was 0.70). When flow of water down the digestive tract was examined in fistulated animals consuming the high quality meadow hay, both species gained water across the R but there was a greater proportional addition of water across the R of kids compared to lambs such that water flow out of the abomasum was similar for both species. Most water absorption occurred in the small intestine of both species and there was no difference in faecal water output between the species. There was no consistent difference between the species in the route of water excretion (urine water/faecal water). It was concluded that, with high quality forages used to promote live weight gain, there was little difference between kids and lambs in the utilization of forage. With low quality maintenance or sub maintenance forages, kids appeared able to obtain and maintain higher levels of nutrient input.

The literature on the effects of phytohormone on algae is clouded with contradictory reports. Reports have been published which substantiate and deny the effects of phytohormones in enhancing the growth and developmental processes in algae. The overall aim of this study was to investigate the response, if any, of the phytohormones indole-3-acetic acid (IAA), gibberellic acid A3 (GA) and kinetin on the physiology of the green alga, Scenedesmus quadricauda. Results obtained for the uptake of 14^C-IAA an(j l4C-kinetin by Scenedesmus strongly support the presumption that the alga does not absorb the hormones. The retention of the phytohormones by the alga is due to adsorption, and is independent of hormone concentration. Most of the label was adsorbed by the outer pectic layers of the cell wall.