Metal tube used as solar engine

Ends of metal tube are fastened to axles which are supported on bearings so tube can rotate about its long axis while subjected to invariant bending moment that stresses it along longitudinal axis of rotation. Heat absorbed leads to expansion of metal, which unbalances internal forces and generates rotational moment in tube

Solid medium thermal engine

A device is described which uses a single phase metallic working substance to convert thermal energy directly into mechanical energy. The device consists of a cylindrical metal tube which is free to rotate about its axis while being subjected to continuous bending moment stresses along the longitudinal axis of rotation. The stressing causes portions of the tube to be under compression while other parts are under tension which in turn causes the tube to rotate and provide mechanical energy

Ultrapure glass optical waveguide: Development in microgravity by the sol gel process

The sol-gel process for the preparation of homogeneous gels in three binary oxide systems was investigated. The glass forming ability of certain compositions in the selected oxide systems (SiO-GeO2, GeO2-PbO, and SiO2-TiO2) were studied based on their potential importance in the design of optical waveguide at longer wavelengths

Where Do I Belong?: Gender And/Or Sexual Minority Students And Leaders In International Schools

The heteronormative ordering of schools poses challenges for gender and/or sexual minorities (GSM). GSM leaders in schools are challenged by decisions about whether to come out of the closet and the implications that these decisions can have for the leadership they enact and their career trajectories. Meanwhile, GSM students face difficulties including identity-based victimization and diminished sense of belonging in school. The experiences of attending high school are further complicated for students who attend an international school outside their country of origin. This qualitative investigation explored how GSM former students at international schools experienced a sense of belonging at school and understood any changes in their sense of belonging at school after interacting with a visible GSM leader in their school. Guided by queer theory and employing interpretive phenomenological analysis, this study addressed both the diminished sense of belonging experienced by GSM students in schools and the gaps in literature surrounding GSM students, GSM leaders, and international schools. Analysis of semi-structured interviews with six GSM former students at international schools yielded three findings. Sense of belonging in school is connected to both (1) identity-related and (2) contextual factors. Further, (3) GSM leaders can serve as a support structure for GSM students in certain cases. The findings of the current research suggest that changes need to be made both in the ways that international schools are structured and how students with marginalized identities are supported

What do young children know about numerosity? : implications for teachers

Numerosity is the ability to count a set of objects using the correct number names in the proper order. Fuson and Hall (1983) assert that the use of cardinal words is one measure of the development of number knowledge. Using words in a cardinal context indicates that children are beginning to understand the manyiness of objects. The use of cardinal words is one of the best indicators that a child is beginning to understand counting and the underlying principles involved. Numerosity is a concept which children often, but not always, demonstrate with overt behaviors. Understanding cardinality and numerical order, develops with an understanding of numerosity Assessing numerosity skills is one of the most reliable gauges of overall mathematical development in the preschool child

Effect of IRC Code 1031 on Texas Agricultural Land Price

In this paper, we examine the effect of Section 1031 tax deferred payment on Texas agricultural land price. To analyze the effects, we estimate the market equilibrium price function using the dynamic panel model and Texas agricultural land sales for 1965-2007. We argue that Section 1031 increases both demand and supply of agricultural land by its tax reducing effect. Our empirical estimation shows that Section 1031 decreases the market price which means the supply curve shifted to the right more than the demand curve.Land Economics/Use,

Effects of lattice distortion and Jahn–Teller coupling on the magnetoresistance of La0.7Ca0.3MnO3 and La0.5Ca0.5CoO3 epitaxial films

Studies of La0.7Ca0.3MnO3 epitaxial films on substrates with a range of lattice constants reveal two dominant contributions to the occurrence of colossal negative magnetoresistance (CMR) in these manganites: at high temperatures (T → TC, TC being the Curie temperature), the magnetotransport properties are predominantly determined by the conduction of lattice polarons, while at low temperatures (T ≪ TC/, the residual negative magnetoresistance is correlated with the substrate-induced lattice distortion which incurs excess magnetic domain wall scattering. The importance of lattice polaron conduction associated with the presence of Jahn–Teller coupling in the manganites is further verified by comparing the manganites with epitaxial films of another ferromagnetic perovskite, La0.5Ca0.5CoO3. Regardless of the differences in the substrate-induced lattice distortion, the cobaltite films exhibit much smaller negative magnetoresistance, which may be attributed to the absence of Jahn–Teller coupling and the high electron mobility that prevents the formation of lattice polarons. We therefore suggest that lattice polaron conduction associated with the Jahn–Teller coupling is essential for the occurrence of CMR, and that lattice distortion further enhances the CMR effects in the manganites

Challenges for Novice School Leaders: Facing Today’s Issues in School Administration

Challenges for novice school leaders evolve as information is managed differently and as societal and regulatory expectations change. This study addresses unique challenges faced by practicing school administrators (n=159) during their first three years in a school leadership position. It focuses on their perceptions, how perceptions of present novices compare to those of experienced school leaders, and how pre-service programs can better prepare them for these challenges. Findings showed that perceptions of present novice school leaders vary somewhat from those of experienced school leaders. Two themes shared relatively the same prominence among experienced leaders as they did with novices: navigating politics and gaining a sense of credibility. Experienced leaders expounded more on specific political hurdles with school boards, other teachers, and parents, and—regarding these same populations—experienced leaders voiced that they wished they had been more successful in their earlier years in developing credibility more quickly with stakeholders. A theme not occurring at all among present novices but noted by five experienced leaders was that of adjusting to the culture of a new school as its leader. This phenomenon may be explained by the value more seasoned leaders have developed for factors inherent in a campus culture