A Study of Evaporation Heat Transfer Coefficient Correlations at Low Heat and Mass Fluxes for Pure Refrigerants and Refrigerant Mixtures

An average R12 refrigerant correlation has been developed for the mass flux range of 25-100 kg/m2-s and the heat flux range of 2-10 kW/m2. Refrigerant mixtures of 80% R22/lO% R141b and 65% R22/35% R123 have also been tested over asjrniJar range of conditions. Mixture heat transfer coefficients have been detennined and correlations for each mixture pair are presented. The R221R141b average correlation may have a strong dependence on changes in surface tension. The heat transfer coefficient of R22JR141b compares well with that of R12. The heat transfer coefficient of R22/R123 severely under performs R12.Air Conditioning and Refrigeration Center Project 0

Early life growth patterns persist for 12 years and impact pulmonary outcomes in cystic fibrosis

BACKGROUND: In children with cystic fibrosis (CF), recovery from growth faltering within 2 years of diagnosis (Responders) is associated with better growth and less lung disease at age 6 years. This study examined whether these benefits are sustained through 12 years of age. METHODS: Longitudinal growth from 76 children with CF enrolled in the Wisconsin CF Neonatal Screening Project was examined and categorized into 5 groups: R12, R6, and R2, representing Responders who maintained growth improvement to age 12, 6, and 2 years, respectively, and I6 and N6, representing Non-responders whose growth did and did not improve during ages 2-6 years, respectively. Lung disease was evaluated by % predicted forced expiratory volume in one second (FEV1) and chest radiograph (CXR) scores. RESULTS: Sixty-two percent were Responders. Within this group, 47% were R12, 28% were R6, and 25% were R2. Among Non-responders, 76% were N6. CF children with meconium ileus (MI) had worse lung function and CXR scores compared to other CF children. Among 53 children with pancreatic insufficiency without MI, R12 had significantly better FEV1 (97-99% predicted) and CXR scores during ages 6-12 years than N6 (89-93% predicted). Both R6 and R2 experienced a decline in FEV1 by ages 10-12 years. CONCLUSIONS: Early growth recovery in CF is critical, as malnutrition during infancy tends to persist and catch-up growth after age 2 years is difficult. The longer adequate growth was maintained after early growth recovery, the better the pulmonary outcomes at age 12 years

Time variation of total electron content over Tucumán

Este trabajo presenta un análisis de la variabilidad del contenido electrónico total, TEC, sobre Tucumán (26.9S; 294.6E; Dip: -21.1) usando mediciones obtenidas por medio de la técnica Faraday durante el período de alta actividad solar comprendido entre abril de 1982 (R12=114) y marzo de 1983 (R12= 75). Los parámetros de variabilidad seleccionados para el estudio han sido la desviación standard del valor promedio s y el índice de variabilidad v = (desviación estándar / promedio) x 100. Las variaciones diurnas y estacionales de ambos parámetros de variabilidad han sido analizadas. Un estudio comparativo con la variabilidad día a día de la frecuencia crítica de la región F2, foF2, ha sido también llevado a cabo. Una tabla de valores de la variabilidad relativa v es presentada. Estudios adicionales se recomiendan con el objeto de extender este tipo de análisis a datos de TEC obtenidos en distintas condiciones geográficas y geofísicas.12=114) y marzo de 1983 (R12= 75). Los parámetros de variabilidad seleccionados para el estudio han sido la desviación standard del valor promedio s y el índice de variabilidad v = (desviación estándar / promedio) x 100. Las variaciones diurnas y estacionales de ambos parámetros de variabilidad han sido analizadas. Un estudio comparativo con la variabilidad día a día de la frecuencia crítica de la región F2, foF2, ha sido también llevado a cabo. Una tabla de valores de la variabilidad relativa v es presentada. Estudios adicionales se recomiendan con el objeto de extender este tipo de análisis a datos de TEC obtenidos en distintas condiciones geográficas y geofísicas.The day-to-day variability of total electron content, TEC, at Tucumán (26.9S; 294.6E; Dip: -21.1) has been studied. The database includes TEC measurements by Faraday rotation during the high solar activity period from April 1982 (R12= 114) to March 1983 (R12= 75). Two variability parameters have been used in the analysis: the standard deviation from the mean values s and the variability index v = (standard deviation/mean value) x100. The diurnal and seasonal variations of both variability parameters have been analyzed. A comparative analysis with the day-to-day variability of critical frequency in the F2 region, foF2, is presented. A table of values of the relative variability v is presented in terms of seasons and typical hours. Additional studies are suggested in order to extend the results to other geographical and geophysical conditions.Fil: Mosert, Marta Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Complejo Astronómico "El Leoncito". Universidad Nacional de Córdoba. Complejo Astronómico "El Leoncito". Universidad Nacional de la Plata. Complejo Astronómico "El Leoncito". Universidad Nacional de San Juan. Complejo Astronómico "El Leoncito"; ArgentinaFil: Ezquer, Rodolfo Gerardo. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Física. Laboratorio de Ionósfera; Argentina. Universidad Tecnológica Nacional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Jadur, Camilo Alberto. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Matemáticas; ArgentinaFil: Oviedo, Rosario del Valle. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Física. Laboratorio de Ionósfera; Argentin

Direct synthesis of methanol by partial oxidation of methane with oxygen over cobalt modified mesoporous H-ZSM-5 catalyst

This work was funded by International Collaboration Research Grant UI No.1832/H2.R12/HKP.05.00 Perjanjian/2014.Peer reviewedPublisher PD

Photon sensitivity of superheated drop at room temperature

It has been reported so far that superheated drop detector made of R-12 at room temperature are sensitive to neutrons yet insensitive to photons. This property makes its use as one of the most useful neutron dosimeter. The photon sensitivity of R12 at room temperature when exposed to 59.54kev photons obtained from radioactive Am has been noted for the first time in our laboratory. This discovery is important nt only from the point of view of basic science but more important to the users of R12 in neutron dosimetry to take note of this in assessing the neutron dose correctly.Comment: 3pages, 1 fig. Nuclear Instruments and Method A, 2000, (accepted

Universality in sandpiles

We perform extensive numerical simulations of different versions of the sandpile model. We find that previous claims about universality classes are unfounded, since the method previously employed to analyze the data suffered a systematic bias. We identify the correct scaling behavior and conclude that sandpiles with stochastic and deterministic toppling rules belong to the same universality class.Comment: 4 pages, 4 ps figures; submitted to Phys. Rev.

From Motion to Emotion : Accelerometer Data Predict Subjective Experience of Music

Music is often discussed to be emotional because it reflects expressive movements in audible form. Thus, a valid approach to measure musical emotion could be to assess movement stimulated by music. In two experiments we evaluated the discriminative power of mobile-device generated acceleration data produced by free movement during music listening for the prediction of ratings on the Geneva Emotion Music Scales (GEMS-9). The quality of prediction for different dimensions of GEMS varied between experiments for tenderness (R12(first experiment) = 0.50, R22(second experiment) = 0.39), nostalgia (R12 = 0.42, R22 = 0.30), wonder (R12 = 0.25, R22 = 0.34), sadness (R12 = 0.24, R22 = 0.35), peacefulness (R12 = 0.20, R22 = 0.35) and joy (R12 = 0.19, R22 = 0.33) and transcendence (R12 = 0.14, R22 = 0.00). For others like power (R12 = 0.42, R22 = 0.49) and tension (R12 = 0.28, R22 = 0.27) results could be almost reproduced. Furthermore, we extracted two principle components from GEMS ratings, one representing arousal and the other one valence of the experienced feeling. Both qualities, arousal and valence, could be predicted by acceleration data, indicating, that they provide information on the quantity and quality of experience. On the one hand, these findings show how music-evoked movement patterns relate to music-evoked feelings. On the other hand, they contribute to integrate findings from the field of embodied music cognition into music recommender systems

Ground state of N=Z doubly closed shell nuclei in CBF theory

The ground state properties of N=Z doubly closed shell nuclei are studied within correlated basis function theory. A truncated version of the Urbana v14 realistic potential, with spin, isospin and tensor components, is adopted, together with state dependent correlations. Fermi hypernetted chain integral equation and single operator chain approximation are used to evaluate density, distribution function and ground state energy of 16O and 40Ca. The results favourably compare with the available, variational MonteCarlo estimates and provide a first substantial check of the accuracy of the cluster summation method for state dependent correlations. We achieve in finite nuclei at least the same level of accuracy in the treatment of non central interactions and correlations as in nuclear matter. This opens the way for a microscopic study of medium heavy nuclei ground state using present days realistic hamiltonians.Comment: 35 pages (LateX) + 3 figures. Phys.Rev.C, in pres

Hypernetted-chain study of broken rotational symmetry states for the ν\bm{\nu} = 1/3 fractional quantum Hall effect and other fractionally filled Landau levels

We investigate broken rotational symmetry (BRS) states for the fractional quantum Hall effect (FQHE) at 1/3-filling of the valence Landau level (LL). Recent Monte Carlo calculations by Musaelian and Joynt [J. Phys.: Condens.\ Matter {\bf 8}, L105 (1996)] suggest that Laughlin's state becomes unstable to a BRS state for some critical finite thickness value. We study in detail the properties of such state by performing a hypernetted-chain calculation that gives results in the thermodynamic limit, complementing other methods which are limited to a finite number of particles. Our results indicate that while Laughlin's state is stable in the lowest LL, in higher LLs a BRS instability occurs, perhaps indicating the absence of FQHE at partial fillings of higher LLs. Possible connections to the newly discovered liquid crystalline phases in higher LLs are also discussed.Comment: 7 pages including 3 eps figure