Contact Ion Engine System for ATS Satellites D and E Annual Progress Report

Performance testing of ion microthruster systems for Applications Technology Satellite

Program to develop and demonstrate method to deflect beam for ion thrustor Final progress report, 6 Dec. 1965 - 6 Jun. 1966

Electrostatic electrodes used for deflecting ion beam from ion thrusto

Study and Design of a Cesium Bombardment Ion Engine System

Cesium bombardment ion engine system design, modification, and testin

Direct thermal conductance measurements on suspended monocrystalline nanostructures

We describe and demonstrate a new class of devices that enable direct thermal conductance measurements on monocrystalline nanostructures. These are possible through our newly developed techniques for three-dimensional, successive surface nanomachining of GaAs-based heterostructures. Our methods allow the patterning of complex devices comprising electrically insulating, mesoscopic thermal conductors with separate, thermal transducers in situ. Intimate thermal contact between these elements is provided by their epitaxial registry. Low-temperature thermal conductance measurements indicate that phonon boundary scattering in these initial nanometer is scale structures is partially specular. These devices offer promise for ultrasensitive bolometry and calorimetry

Phonon scattering mechanisms in suspended nanostructures from 4 to 40 K

We have developed specially designed semiconductor devices for the measurement of thermal conductance in suspended nanostructures. By means of a novel subtractive comparison, we are able to deduce the phonon thermal conductance of individual nanoscale beams of different geometry and dopant profiles. The separate roles of important phonon scattering mechanisms are analyzed and a quantitative estimation of their respective scattering rates is obtained using the Callaway model. Diffuse surface scattering proves to be particularly important in the temperature range from 4 to 40 K. The rates of other scattering mechanisms, arising from phonon-phonon, phonon-electron, and phonon-point defect interactions, also appear to be significantly higher in nanostructures than in bulk samples

Nanoscale, Phonon-Coupled Calorimetry with Sub-Attojoule/Kelvin Resolution

We have developed an ultrasensitive nanoscale calorimeter that enables heat capacity measurements upon minute, externally affixed (phonon-coupled) samples at low temperatures. For a 5 s measurement at 2 K, we demonstrate an unprecedented resolution of ΔC ~ 0.5 aJ/K (~36 000 k_B). This sensitivity is sufficient to enable heat capacity measurements upon zeptomole-scale samples or upon adsorbates with sub-monolayer coverage across the minute cross sections of these devices. We describe the fabrication and operation of these devices and demonstrate their sensitivity by measuring an adsorbed ^4He film with optimum resolution of ~3 × 10^(-5) monolayers upon an active surface area of only ~1.2 × 10^(-9) m^2

Contact ion engine system for ATS satellites D and E Annual progress report, 22 Mar. 1967 - 22 Mar. 1968

Ion microthrustor systems and ground support equipment for Applications Technology Satellites D and

Herramienta para estimar el contenido residual de sorbato de potasio en ciruela deshidratada tiernizada, en función de la concentración y aplicación de conservante utilizado

Tesis para obtener el grado de Master Internacional en Tecnología De Alimentos, presentada en la Facultad de Agronomía, Universidad de Buenos Aires y la Università degli Studi di Parma en mayo de 2017Durante la elaboración de ciruela deshidratada la fruta se somete a un proceso de secado que finaliza al alcanzar una humedad del 20% o inferior. Posteriormente, se realiza el tiernizado, por exposición a vapor y/o agua caliente, con el objetivo de eliminar microorganismos y adquirir una textura agradable para el consumidor. En esta etapa se le incorpora humedad a la fruta, por lo cual es necesario emplear un conservante para protegerla del deterioro por hongos y levaduras. El conservante comúnmente utilizado para este proceso es el sorbato de potasio, el cual se emplea como antimicótico. Para asegurar que el producto final contenga una adecuada cantidad del conservante se realizan determinaciones de sorbato de potasio a través de diversas técnicas analíticas. Para ello es necesario contar con el equipamiento y personal idóneos. Sin embargo, no todos los productores y empresas elaboradoras cuentan con estos recursos. Es por ello, que el presente trabajo de investigación pretende evaluar el contenido residual de sorbato de potasio en ciruela d’Agen deshidratada tiernizada, en la cual se han aplicado distintas dosis del conservante y formas de aplicación (inmersión o aspersión), con el propósito de generar una herramienta que le permita a los elaboradores estimar el contenido del conservante residual en función de la concentración y del tipo de aplicación realizada.EEA Rama CaídaFil: Worlock, Jesica. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Rama Caída; Argentin