A Comparison of Photocatalytic Oxidation Reactor Performance for Spacecraft Cabin Trace Contaminant Control Applications

Photocatalytic oxidation (PCO) is a maturing process technology that shows potential for spacecraft life support system application. Incorporating PCO into a spacecraft cabin atmosphere revitalization system requires an understanding of basic performance, particularly with regard to partial oxidation product production. Four PCO reactor design concepts have been evaluated for their effectiveness for mineralizing key trace volatile organic com-pounds (VOC) typically observed in crewed spacecraft cabin atmospheres. Mineralization efficiency and selectivity for partial oxidation products are compared for the reactor design concepts. The role of PCO in a spacecraft s life support system architecture is discussed

Exploration Mission Particulate Matter Filtration Technology Performance Testing in a Simulated Spacecraft Cabin Ventilation System

Human deep space exploration missions will require advances in long-life, low maintenance airborne particulate matter filtration technology. As one of the National Aeronautics and Space Administrations (NASA) developments in this area, a prototype of a new regenerable, multi-stage particulate matter filtration technology was tested in an International Space Station (ISS) module simulation facility. As previously reported, the key features of the filter system include inertial and media filtration with regeneration and in-place media replacement techniques. The testing facility can simulate aspects of the cabin environment aboard the ISS and contains flight-like cabin ventilation system components. The filtration technology test article was installed at the inlet of the central ventilation system duct and instrumented to provide performance data under nominal flow conditions. In-place regeneration operations were also evaluated. The real-time data included pressure drop across the filter stages, process air flow rate, ambient pressure, humidity and temperature. In addition, two video cameras positioned at the filtration technology test articles inlet and outlet were used to capture the mechanical performance of the filter media indexing operation under varying air flow rates. Recent test results are presented and future design recommendations are discussed

Performance Testing of a Photocatalytic Oxidation Module for Spacecraft Cabin Atmosphere Revitalization

Photocatalytic oxidation (PCO) is a candidate process technology for use in high volumetric flow rate trace contaminant control applications in sealed environments. The targeted application for PCO as applied to crewed spacecraft life support system architectures is summarized. Technical challenges characteristic of PCO are considered. Performance testing of a breadboard PCO reactor design for mineralizing polar organic compounds in a spacecraft cabin atmosphere is described. Test results are analyzed and compared to results reported in the literature for comparable PCO reactor designs

Disponibilidade de zinco para as culturas do milho, sorgo e soja em Latossolo Vermelho-Escuro argiloso

Two field experiments were carried out on a Typic Haplusthox (clayey, kaolinitic, isohyperthermic) originally under cerrado vegetation, to evaluate the effects of zinc on maize (Zea mays L.), sorghum (Sorghum bicolor (L.) Moench), and soybean (Glycine max (L.) Merrill) yields and the effect of pH on zinc availability to maize. In the first experiment the main plots received, once only, 0, 1, 3, 9 and 27 kg/ha of zinc broadcast. The subplots were sown in the first year with three maize genotypes; in the second year, only 'Cargill 111’ maize was sown; in the third year. 'Cargill 111’ and RS 610 sorghum were sown, while in the fourth year 'Cargill 111’and ‘lAC-2’ soybean were sown. The 3 kg/ha rate was sufficient to maintain near-maximum maize yield for at least four consecutive crops. For 'Cargill 111’maize the soil critical levels were 1.4 ppm, 1.0 ppm and 0.7 ppm for the 0.1N HCl, 0.05N HCl + 0.025N H2SO4, and DTPA-TEA extractants, respectively. In the second experiment, 75, 15 and 22.5 t/ha of lime and 0.3, and 9 kg/ha of zinc were applied in a factorial design. The pH increase decreased maize yields.Foram conduzidos dois experimentos de campo para avaliar o efeito de doses de zinco na produção de milho (Zea mays L.), do sorgo (Sorghum bicolor (L.) Moench) e da soja (Glycine max (L.) Merrill), e o efeito do pH na disponibilidade do zinco para o milho. Nas parcelas principais do primeiro experimento, foram aplicados a lanço e, apenas no primeiro ano, 0, 1, 3, 9 e 27 kg/ha de zinco. Nas subparcelas, cultivaram-se, no primeiro ano, três genótipos de milho; no segundo ano, apenas o milho 'Cargill 111'; no terceiro ano, o 'Cargill 111' e o sorgo cv. RS 610; no quarto ano, o 'Cargill 111' e a soja cv. IAC-2. A dose de 3 kg/ha de zinco foi suficiente para manter as produções de milho próxima ao máximo por, pelo menos, quatro colheitas consecutivas. Os níveis críticos de zinco no solo para o milho 'Cargill 111' foram de 1,4 ppm, 1,0 ppm e 0,7 ppm quando se usou, respectivamente, HCl 0,1 N, HCl 0,05 N + H2SO40,025 N e DTPA-TEA, como soluções extratoras. No segundo experimento, utilizaram-se três doses de zinco (0, 3 e 9 kg/ha) e três doses de calcário (7,5; 15; e 22,5 t/ha) num esquema fatorial. A elevação do pH causou decréscimo na produção dos três genótipos de milho

Administración financiera y toma de decisiones en la institución educativa privada Enrique Espinosa 2019

La presente investigación tuvo como objetivo determinar la relación existente entre la Administración financiera y la Toma de decisiones en la Institución Educativa Enrique Espinosa. El estudio fue de tipo básica descriptiva con un enfoque cuantitativo de diseño no experimental, con alcance correlacional y usó el método hipotético deductivo. El trabajo de campo contó con una población total de 80 personas, todos colaboradores de la institución educativa. La muestra fue de carácter censal todos los colaboradores fueron parte del estudio. La técnica usada para la recolección de datos fue la encuesta, los instrumentos usados fueron el cuestionario de Administración financiera y el de toma de decisiones; el primero de ellos con un Alfa de Cronbach de 0.801 y el segundo con 0.833. El estudio se sustenta su base teórica en la teoría general de finanzas de Gitman en la cual se establece su principal prioridad en las decisiones de financiamiento de cualquier tipo de activo que posee una empresa. Asimismo, el estudio explica la teoría de la holgura financiera de Van Horne, en donde se indica que las organizaciones deben de poseer determinadas características para llegar al financiamiento rápido de inversiones. Por otra parte, en cuanto a la teoría de Toma de decisiones, la presente investigación centra su atención en la teoría de juego de Kelly en donde cada jugador posee un rol determinante en el proceso de la toma de decisión; así como los modelos de tomas de decisiones planteados por Fitzgerald, que van desde los modelos más lógicos hasta los más complejos. Los resultados arrojaron que el 72.5% de los encuestados percibe un buen nivel de administración financiera en la institución educativa privada Enrique Espinosa. Mientras que el 96.25% de los mismos consideran que la toma de decisiones en la misma institución es acertada. Finalmente, se pudo concluir con la investigación que la relación que existe entre las variables es moderada y significativa con Rho de Spearman de 0.426 y p<0.05, implicando rechazar la hipótesis nula

Discussions and Reviews : Theorizing about theory in international politics

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66906/2/10.1177_002200276000400405.pd