601 research outputs found
Tabulated values of cavitation B-factor for helium, H2, N2, F2, O2, Refrigerant 114, and H2O
Tabulated values of cavitation b-factor for helium, H2, N2, F2, O2, refrigerant 114, and H2
Incipient and developed cavitation in liquid cryogens
Cavitational flow of liquid nitrogen and liquid hydrogen in Venturi tub
Cavitation in liquid cryogens
Cavitation in liquid hydrogen and nitrogen flowing in transparent plastic ventur
Cavitation in liquid cryogens. 4: Combined correlations for venturi, hydrofoil, ogives, and pumps
The results of a series of experimental and analytical cavitation studies are presented. Cross-correlation is performed of the developed cavity data for a venturi, a hydrofoil and three scaled ogives. The new correlating parameter, MTWO, improves data correlation for these stationary bodies and for pumping equipment. Existing techniques for predicting the cavitating performance of pumping machinery were extended to include variations in flow coefficient, cavitation parameter, and equipment geometry. The new predictive formulations hold promise as a design tool and universal method for correlating pumping machinery performance. Application of these predictive formulas requires prescribed cavitation test data or an independent method of estimating the cavitation parameter for each pump. The latter would permit prediction of performance without testing; potential methods for evaluating the cavitation parameter prior to testing are suggested
Thermodynamic depressions within cavities and cavitation inception in liquid hydrogen and liquid nitrogen Final report, 15 Jul. 1964 - 15 Dec. 1967
Thermodynamic depressions within cavities and cavitation inception in liquid hydrogen and nitrogen in transparent plastic venturi tube
Cavitation inception in liquid nitrogen and liquid hydrogen flowing in a venturi Interim report, 15 Jul. 1964 - 15 Jul. 1967
Cavitation characteristics of liquid hydrogen, and liquid nitrogen flow in plastic ventur
NuSTAR Hard X-ray Observation of the Gamma-ray Binary Candidate HESS J1832-093
We present a hard X-ray observation of the TeV gamma-ray binary candidate
HESS J1832-093 coincident with supernova remnant (SNR) G22.7-0.2 using the
Nuclear Spectroscopic Telescope Array (NuSTAR). Non-thermal X-ray emission from
XMMU J183245-0921539, the X-ray source associated with HESS J1832-093, is
detected up to ~30 keV and is well-described by an absorbed power-law model
with the best-fit photon index . A re-analysis of archival
Chandra and XMM-Newton data finds that the long-term X-ray flux increase of
XMMU J183245-0921539 is % (90% C.L.), much less than previously
reported. A search for a pulsar spin period or binary orbit modulation yields
no significant signal to a pulse fraction limit of fp < 19% in the range 4 ms <
P < 40 ks. No red noise is detected in the FFT power spectrum to suggest active
accretion from a binary system. While further evidence is required, we argue
that the X-ray and gamma-ray properties of XMMU J183245-0921539 are most
consistent with a non-accreting binary generating synchrotron X- rays from
particle acceleration in the shock formed as a result of the pulsar and stellar
wind collision. We also report on three nearby hard X-ray sources, one of which
may be associated with diffuse emission from a fast-moving supernova fragment
interacting with a dense molecular cloud.Comment: ApJ in press. 9 page
Evaluation of two weather-based spray programs for control of mango anthracnose in Costa Rica
Se realizaron dos experimentos en las provincias de Alajuela y Guanacaste, Costa Rica a fin de evaluar dos métodos de combate quÃmico de la antracnosis del mango con base en condiciones meteorológicas. Aplicaciones del fungicida erradicante prochloraz fueron programadas de acuerdo con un sistema desarrollado en Australia basado en temperatura y mojadura foliar, o con una modificación del método australiano que incluÃa la humedad relativa. Ambos métodos fueron comparados con un tratamiento estándar a base de benomil y mancozeb, y con un testigo sin fungicida. La aplicación preventiva de la mezcla benomil + mancozeb durante la floración y el desarrollo del fruto fue el tratamiento más eficaz (p ≤ 0,05) para el combate de la antracnosis en frutos producidos en época lluviosa, con más de un 80% de frutos exportables. El uso de los métodos basados en condiciones meteorológicas (Australiano y el modificado) resultó en un menor número de aplicaciones de fungicidas, pero en una mayor severidad de antracnosis (p ≤ 0,05) en comparación con el tratamiento estándar. No hubo diferencias significativas entre estos métodos y el testigo, con respecto al porcentaje de frutos exportables, el cual fue menor al 15%. En época seca fue innecesario hacer aplicaciones de fungicidas ya que más del 90% de la fruta fue de calidad exportable en todos los tratamientos, sin diferencias estadÃsticas entre ellos.Field trials were conducted in the Alajuela and Guancaste provinces of Costa Rica to evaluate two weather-based spray programs for control of mango anthracnose. Applications of the eradicant fungicide prochloraz were scheduled according to a predictive model developed in Australia based on temperature and leaf wetness, or a modification of the Australian system that included relative humidity. The weather-based spray programs were compared to a standard chemical treatment of benomyl+mancozeb, and to an untreated control. Application of benomyl + mancozeb on a preventive schedule during flowering and fruit development was the most effective treatment (p≤0.05) for control of anthracnose in fruit produced under wet conditions, resulting in >80% exportable fruit. The weather-based spray programs resulted in fewer fungicide applications, but the percentage of exportable fruit produced in wet conditions was <15% and did not differ from the untreated control. Use of the weatherbased systems during dry conditions resulted in unnecessary fungicide applications; more than 90% of the fruit were of export quality with no significant differences among treatments.UCR::VicerrectorÃa de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Estación Experimental AgrÃcola Fabio Baudrit Moreno (EEAFBM
Mariner 6 and 7 ultraviolet spectrometer experiment - Upper atmosphere data
Ultraviolet emissum spectrum of Mars upper atmosphere from Mariner 6 and 7 spaceprobe
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