Corrosion is one of the most complicated and costly problems facing drinking water utilities. Corrosion of iron pipes can lead to economic losses and customer complaints, while lead corrosion poses a serious health risk. This work first synthesizes nearly 100 years of iron corrosion research to provide the water industry with an updated understanding of factors that influence iron pipe corrosion including water quality and composition, flow conditions, biological activity, and corrosion inhibitors. Potential impacts of upcoming regulations on iron corrosion are also considered. Next, a four-year study is presented that evaluated the effect of water quality and phosphate inhibitors on the corrosion of iron pipes under extended stagnant water conditions. Surprisingly, many of the water quality parameters traditionally thought to influence iron corrosion were not controlling under these "worst case" stagnant conditions. Moreover, addition of phosphate inhibitors often had either no statistically significant effect or actually increased iron concentration, scale build-up and overall weight loss. Temperature is often overlooked when corrosion of distribution systems pipes is considered. Temperature impacts many parameters that are critical to pipe corrosion including physical properties of the solution, thermodynamic and physical properties of corrosion scale, chemical rates, and biological activity. Moreover, variations in temperature and temperature gradients may give rise to new corrosion phenomena worthy of consideration by water treatment personnel. In laboratory experiments, cast iron samples at 5°C had 23% more weight loss, ten times higher iron release to water, and twice as much tuberculation compared to samples at 25°C. For lead corrosion, hexametaphosphate inhibitors were proven to increase release of both particulate and soluble lead to drinking water by 200 - 3500% over a wide range of water qualities when compared to orthophosphate, effectively ending a long term debate as to their impacts. Utilities should consider these adverse effects whenever polyphosphate is used to prevent scaling or iron precipitation. / Ph. D.

The research presented in this thesis represents an effort to characterize the properties of ultra-high molecular weight polyethylene (UHMWPE). As a composite of polymers, the properties of UHMWPE are time-dependent. It is desired by research sponsors to know the properties of the material at high strain rates, in order to simulate the use of these materials in computer models. Properties believed to be significant which are investigated in this research are the tensile properties of lamina and laminates, and the interlaminar shear properties of laminates. The efficacy of using time-temperature superposition to shift tensile properties of the composite is investigated, and a novel apparent shear strength test is proposed and demonstrated. The effects of processing the material at various temperatures and pressures are also investigated. / Master of Science

To fulfill the objective of providing robust and reliable fiber optic temperature sensors capable of operating in harsh environments, a novel type of fiber optic sensor system titled self-calibrated interferometric/intensity-based (SCIIB) fiber optic temperature sensor system is presented in this thesis including the detailed research work on the principle analysis, design, modeling, implementation and performance evaluation of the system. The SCIIB fiber optic temperature sensor system shows us an innovative fiber optic sensor system compared with traditional fiber optic sensors. In addition to the general benefits of the traditional fiber optic sensors, the SCIIB fiber optic sensor system possesses several unique advantages. By taking advantage of the Split-Spectrum technique developed in Photonics Lab at Virginia Tech, the SCIIB sensor technology possesses the capability of Self-Calibration that can fully compensate for the fluctuation of optical source power and the variations of fiber losses. It combines the advantages of both the interferometric-based and the intensity-based fiber optic sensors in a single system. A multimode fiber-based SCIIB temperature sensor system is designed and successfully implemented. Comprehensive experiments are performed to evaluate the principle of SCIIB technology and the performance of the multimode fiber-based SCIIB temperature sensor system. The experiment results illustrate that the development of the SCIIB fiber optic temperature sensor system provides a reliable tool for the temperature measurement capable of operation in high temperature harsh environments. / Master of Science

Yes / Condition monitoring of micro injection moulding is an effective way of understanding the processing effects of variable parameter settings. This paper reports an experimental study that investigates the characteristics of the demoulding behaviour in micro injection moulding (A mu-IM) with a focus on the process factors that affect parts' quality. Using a Cyclic Olefin Copolyme (COC) microfluidics demonstrator, the demoulding performance was studied as a function of four process parameters (melt temperature, mould temperature, holding pressure and injection speed), employing the design of experiment approach. The results provide empirical evidences on the effect that processing parameters have on demoulding conditions in A mu-IM, and identifies combinations of parameters that can be used to achieve the optimal processing conditions in regards to demoulding behaviour of micro parts. It was concluded that there was a direct correlation between the applied pressure during part filling, holding phases and the demoulding characteristic factors of the A mu-IM cycle such as ejection force, integral and time.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

Hur mycket lufttemperaturen varierar på en plats på land beror till stor del av platsens avstånd till havet. Ju längre ifrån havet platsen ligger, ju mindre influeras dess lufttemperatur av havstemperaturen. Hav värms och kyls långsammare än land vilket innebär att maritima platser har en stabilare lufttemperatur i jämförelse med inlandet.             Syftet med denna studie är att undersöka lufttemperaturer på en liten ö för att bestämma i vilken grad havsavståndet påverkar temperaturvariationer på liten skala. Mätningarna skedde på ön Mefjärd i Stockholms skärgård. Mefjärd har en storlek på ca 3000 x 400 m och är belägen drygt 10 km från Sveriges östkust. Mätningar av lufttemperatur gjordes kontinuerligt mellan den 20/3 och 22/4 både vid strandlinjen och vid mitten av ön. Även havstemperatur, vind och solinstrålning mättes. Statistiska beräkningar genomfördes och grafer över temperaturer och resterande uppmätt data skapades. Resultaten visade bland annat att lufttemperaturen vid strandlinjen var stabilare och generellt sätt närmare havstemperaturen än vad lufttemperaturen mitt på ön var samt att lufttemperaturen mitt på ön var känsligare för skillnader i solinstrålning än lufttemperaturen vid strandlinjen. Dessa resultat var tydliga trots att studien utfördes på liten skala. / The amount of air temperature variation at some location on land depends to a large extent on the distance between the location and the sea. The further from the sea a place is located, the less is its air temperature influenced by the sea temperature. The sea is heated and cooled more slowly than land which means that maritime locations has a more stable air temperature compared to inland locations.             The purpose of this study is to examine air temperatures on a small island in order to determine to what extent air temperature variations are influences by distance to sea, on a small scale. Measurements were taken on the island Mefjärd in the archipelago of Stockholm. Mefjärd is about 3000 x 400 m in size, located 10 km from the eastern coast of Sweden. Measurements of air temperature was taken continuously between the 20/3 and 22/4 both by the shoreline and in the middle of the island. Sea temperature, wind and solar radiation were also measured. Statistical calculations were done and figures displaying air temperatures and other measured data were created. The result showed, among other things, that the air temperature by the shoreline was more stable and generally closer to the sea temperature than the air temperature in the middle of the island, and that the air temperature in the middle of the island was more sensitive to changes in sun radiation than the air temperature by the shoreline. These results were apparent even though the study was conducted on a small scale.

published_or_final_version / abstract / Physics / Doctoral / Doctor of Philosophy

The hydraulic conductance of a plant is a significant factor in determining the / Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2008.

CTMinimum and CTMaximum were measured in 620 goldfish to determine if biotic factors, in particular starvation, condition factor and size, affect temperature tolerance. Twenty-eight days of starvation adversely affected both upper and lower temperature tolerance. Condition factor was related to upper but not lower temperature tolerance.

An experiment was conducted to test the hypothesis that more intelligent Ss would produce greater increases in peripheral skin temperature using autogenic feedback training. At the completion of training, the Ss were divided into two groups by IQ scores and matched with pretraining (baseline) temperatures. The hypothesis was rejected when results opposite to those predicted occurred. Large group differences, however, prompted a po4t-hoc investigation to determine the statistical significance between group performances. This analysis revealed that the less intelligent Ss experienced greater success (p<.05) in increasing skin temperature. Possible explanations for these results are discussed and considerations for future investigations with biofeedback training and intelligence are suggested.