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Ceramic matrix composites (CMCs) offer great potential for developing lighter and more efficient aero-engines. Due to their high-temperature capability, CMCs are mainly used in the hot gas section in order to replace cooled metallic components and thus save cooling air. Especially CMC vanes for high-pressure turbines (HPTs) have been researched and tested in the past. A realistic design approach for cooled CMC vanes is the so-called shell and spar concept. The application of such vanes in HPTs as inlet guide vanes (IGVs) at constant rotor inlet temperature (T41) enables performance and emissions benefits which are assessed by means of a reference engine in this paper. Compared to metallic IGVs, more temperature-resistant CMC IGVs require significantly less cooling air and generate lower cooling losses. A quantitative comparison will be presented. Consequently, the redesign of the reference engine to the setting of a hybrid HPT leads to a reduction in thrust specific fuel consumption (TSFC) by 0.23% at cruise conditions. Additionally, there is potential to extract the IGV cooling air at a lower pressure level, increasing the cruise TSFC gain to 0.41%. In the course of the redesign process, the turbine inlet temperature (T4) is reduced by 50 K in order to reach the same T41 with a lower IGV coolant mass flow. Regarding emissions, this leads to a decreased production of nitrogen oxides (NOx). Hence, several NOx emissions parameters can be reduced by more than 4%. [ABSTRACT FROM AUTHOR]

Abstract: In order to establish the effect of alumina modification and calcination temperature on the reducibility of cobalt oxide, alumina-modified cobalt oxide crystallites containing less than 2.5 wt% Al were prepared via incipient wetness impregnation, and calcined at 300 °C or 500 °C. The catalysts were characterised using X-ray diffraction, scanning transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy, temperature programmed reduction (TPR) and X-ray absorption near edge spectroscopy. The alumina modification was found to prevent sintering during calcination and decrease the reducibility of the catalysts. With increasing alumina loading, and increasing calcination temperature, reduction peaks shift to higher temperatures and peaks above 400 °C appear in the TPR. The kinetic evaluation shows that the decreased reducibility is due to a decrease in the pre-exponential factor, which suggests that the alumina modification hinders hydrogen activation and the nucleation of reduced cobalt phases. The catalysts are completely reduced below 800 °C, and no CoAl2O4 phase formation was observed. TPR peaks between 400 and 650 °C were assigned to the formation of a non-stoichiometric cobalt-alumina phase with cobalt ions in octahedral coordination, while peaks between 650 and 800 °C correspond to cobalt ions in tetrahedral coordination. The results show that introduction of small amounts of alumina to cobalt oxide can have drastic effects on the rate of reduction and sintering.Graphical Abstract: [ABSTRACT FROM AUTHOR]

This article focuses on administrative problems of a women's reformatory. They are of a great many types and may be interpreted from a great many angles, but after carefully sifting them they seem to fall into four relative classes, namely: those which involve the public, those which involve the board of directors, those which pertain to the staff, and those which pertain to the inmates. Social agencies with public or private subsidies are doing relief work or investigative work of one kind or another. In this connection may also be cited the police department of the state because it comes in contact with most of the wards that come to institutions. Another group that is included in the public are the judges who commit the women to the reformatory. Large sums of money must be appropriated to establish the physical side of the organization and other sums of money must be secured to provide the staff which forms the other part of the organization.

To summarize an innovative initiative in oncology nurse workforce development that addresses critical current and future gaps and encompasses use of dedicated education units for student nurse rotation and a transition-to-practice residency program. Review of institutional data including original pilot analysis and ongoing programmatic metrics (N=8 years), consensus, professional guidelines, and published literature. The dedicated education unit serves as a conduit for recruitment into institutional oncology nurse residency positions, and retention rates in the residency program continue to exceed national averages. Subsequent mentoring of these nurses in transition to practice has manifested high rates of promotion into nurse leadership roles year over year. Oncology nurse practice incorporates state-of-the-science approved therapies, early phase clinical trial implementation, and evidence-based complex oncology patient care management. A new model of student clinical nurse rotations in ambulatory settings, nurse resident transition to practice, and ongoing leadership mentoring is essential in creating a sustainable, highly skilled, and robust oncology nurse work force. [ABSTRACT FROM AUTHOR]