When operating microsystems in harsh environments, many conventionally used techniques are limiting. Further, depending on if the demands arise from the environment or the conditions inside the system, different approaches have to be used. This thesis deals with the challenges encountered when microsystems are used at high pressures and high temperatures. For microsystems operating at harsh conditions, many parameters will vary extensively with both temperature and pressure, and to maintain control, these variations needs to be well understood. Covered within this thesis is the to-date strongest membrane micropump, demonstrated to pump against back-pressures up to 13 MPa, and a gas-tight high pressure valve that manages pressures beyond 20 MPa. With the ability to manipulate fluids at high pressures in microsystems at elevated temperatures, opportunities are created to use green solvents like supercritical fluids like CO2. To allow for a reliable and predictable operation in systems using more than one fluid, the behavior of the multiphase flow needs to be controlled. Therefore, the effect of varying temperature and pressure, as well as flow conditions were investigated for multiphase flows of CO2 and H2O around and above the critical point of CO2. Also, the influence of channel surface and geometry was investigated. Although supercritical CO2 only requires moderate temperatures, other supercritical fluids or reactions require much higher temperatures. The study how increasing temperature affects a system, a high-temperature testbed inside an electron microscope was created. One of the challenges for high-temperature systems is the interface towards room temperature components. To circumvent the need of wires, high temperature wireless systems were studied together with a wireless pressure sensing system operating at temperatures up to 1,000 °C for pressures up to 0.3 MPa. To further extend the capabilities of microsystems and combine high temperatures and high pressures, it is necessary to consider that the requirements differs fundamentally. Therefore, combining high pressures and high temperatures in microsystems results in great challenges, which requires trade-offs and compromises. Here, steel and HTCC based microsystems may prove interesting alternatives for future high performance microsystems.

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This study sought out the perceptions of middle school (any combination of grades 5-9) educators in 19 states regarding the specific learning experiences that should be included in the curriculum for the preparation of junior high/middle school teachers, the skills or characteristics that are needed by a junior high/middle school teacher to best meet the needs of the early adolescent, the desirability of a discrete middle school certificate and the reasons why or why not. Using the data collected, a paradigm was designed for a junior high/middle school teacher training program that reflected the best thinking of these educators. This middle school study utilized a modified Delphi Technique in surveying the perceptions of administrators, teachers holding secondary certificates and teachers holding elementary certificates currently employed at junior high/middle schools, North Central Association associate state chairmen, and college of education professors. The three primary points emerging from this study are (1) that the lines of communication need to be opened between educators in the junior high/middle schools and those at institutions where policies, teacher preparation programs and certification requirements regarding middle school education (and educators) are being formulated, (2) that those same policies, teacher preparation programs and certification requirements be formulated on the basis of research data gathered directly from those educators in junior high/middle schools, and (3) that a middle school teacher's characteristics are considered by those involved currently in middle school education to be more important than his/her skills.

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The following thesis investigates parametric thinking and evolutionary solving principles in the creation of a framework for residential high rise design. Site specific parameters such as site access (pedestrian and vehicular), views, acknowledgement of neighbours, or climatic, such as natural day lighting and ventilation, should be used to inform the design. Parametric software is used as a tool to generate designs dynamically. With the help of an evolutionary solver component, the design potential is augmented by generating multiple iterations which are analyzed for their success or failure in an effort to provide an appropriate response within the context of the site. The framework is tested on a site located at the corner of Duplex Avenue and Eglinton Avenue West in Toronto, Canada.

Common brown colour in natural diamond forms by plastic deformation during storage in the subcontinental lithospheric mantle (SCLM). Dislocation movement generates vacancies, which aggregate into clusters of perhaps 30–60 vacancies. Positron annihilation lifetime spectroscopy (PALS) and electron energy loss spectroscopy (EELS) support such vacancy clusters as the cause of brown colour. Brief treatment in a high-pressure–high-temperature (HPHT) vessel at 1800–2700 °C can destroy the brown colour. There has been speculation that similar colour removal should occur continuously at depth in the SCLM. Diamonds are stored at 900–1400 °C in the SCLM, according to inclusion thermometry. The effect of temperature on the time required to destroy brown colour has been calculated from published data. The activation energy for the breakup of vacancy clusters is a critical component. The time required to destroy brown colour in the SCLM is significant at the scale of geological time. Brown diamonds should easily maintain their colour for millions of years during cooler mantle storage at or below about 1000 °C. Warmer temperatures toward the base of the lithosphere may be able to reduce or eliminate brown colour within thousands of years. The survival of brown colour in the lithospheric mantle does not require the colour to be formed late in the storage history nor does it require metastable storage in the graphite stability field. Crystal strain is preserved upon loss of brown colour during HPHT treatment. Inhomogeneous crystal strain was measured in 18 natural diamonds using micro-X-ray diffraction (μXRD) χ-dimension peak widths. There is a correlation between strain and depth of brown colour. None of the colourless diamonds examined have high strain, as should be expected for a diamond that has gained and lost brown colour. This suggests that removal of brown colour is not a common natural occurrence. Infrared spectroscopy was used to determine nitrogen concentration and aggregation state in 60 natural diamonds. A loose association was found between brown colour and lower total nitrogen content. Within single diamonds, regions with less nitrogen tend to exhibit more anomalous birefringence due to strain. Colour zoned diamonds tend to have less nitrogen in the darker brown regions. This supports the hypothesis that diamonds with less nitrogen are more susceptible to plastic deformation and the development of brown colour. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2009-09-17 17:10:11.078

The purpose of this study was to investigate how the biological science curriculum was being implemented at the secondary school level in Kenya under the 8-4-4 system of education. In this study, the case method was used to investigate implementation in two secondary schools in Baringo district, Kenya. Data were collected using observation, interviews, questionnaires, and audio recordings. / Implementation standards were found to be rather low because of a number of factors. The general laboratories in the two schools of the study were poorly equipped, and textbooks available to students were too few. Moreover, the textbooks were reported as being shallow and sketchy. In addition, the content of some topics was too difficult especially at the lower secondary (Forms I and II) level. The syllabus was also too wide for satisfactory coverage in the four-year duration of secondary education. / An additional problem found was that there were no inservice courses for the biology teachers. It was also found that the head teachers played a limited role as instructional supervisors because most of their time was spent on administrative duties.

The purpose of this study was to examine the role of the secondary school principal in anglophone Quebec. A sample of eighteen experienced principals were interviewed in-depth about their role expectations, sources of role conflict, and their sense of ambiguity. / Role ambiguity appeared to be non-existent in the principalship. Expectations and conflicts were identified with regard to students, teachers, parents, community members, and principal's superiors. The principalship was clearly more a managerial than leadership role. Principals were responders to a series of problems and issues. They orchestrated responses. Instructional leadership was not a part of their role.