Estimating sorber capacity for multiple contaminants

Computer program estimates quantity of activated charcoal required to control multiple contaminants. Program scans all contaminants by potential parameter value and then orders them from lowest to highest values. It calculates quantity of sorbent required to remove most strongly adsorbed material; and then, using potential plot data, capacity of other materials is calculated on basis of corrected capacity

Study and preliminary design of an isotope- heated catalytic oxidizer system, addendum 1

Isotope-heated catalytic oxidizer system in life support systems for manned space fligh

Process for recovering terephthalic acid from waste polyethylene terephthalate

Terephthalic acid (TPA) is recovered from used polyethylene terephthalate beverage containers by reacting comminuted containers in a reaction zone with an aqueous medium containing ammonium hydroxide at elevated temperatures and pressures to form a water soluble diammonium salt of TP A, separating any undissolved solids from the reaction product, acidifying the remaining reaction product to liberate TP A, and separating the precipitated TPA. A portion of the liquid remaining after separation of TPA can be mixed with lime or slaked lime, the resulting mixture treated in an ammonia stripper to remove ammonia therefrom and the ammonia overheads from the stripper blended with another portion of the liquid remaining after separation of TPA to form a stream containing ammonium hydroxide which is recycled to the reaction zone. Ethylene glycol can be recovered from the bottoms from the ammonia stripper by distillation.https://digitalcommons.mtu.edu/patents/1102/thumbnail.jp

Evaluation testing of zero gravity humidity control system

Design criteria for zero gravity hydrophobic/ hydrophilic type humidity control syste

Contact angles mediate equilibrium fractionation between soil water and water vapor

Soil water potential is a function of grain size, adhesion and cohesion energy. The mechanical equilibrium between the interfacial free energies between water-gas, water-solid and solid-gas, leads to a particular contact angle at the three phase boundary water-solid-gas. The contact angle of the solid-soil affects the water retention in soils. Contact angles >0 lead to a shift of the water retention curve to simulating a coarser soil texture. Thus, a certain amount of water is stronger bound in a soil with a low contact angle compared to the same soil with a high contact angle. The relationship between the contact angle and the fractionation of water stable isotopes between soil water and water vapor has yet not been studied. We present a simple laboratory experiment with soil samples ranging from sand to silt to clay. Two subsamples were hydrophobized (or treated with) using dichlorodimethylsilane to produce different contact angles. Subsamples were transferred into Ziploc bags spiked with water of known isotopic composition and the headspace filled with dry air. After equilibration (at least 24h) the headspace was measured for its isotopic signature with a Laserspectrometer. Soil water potential was measured with a soil water potential meter and the contact angle determined with the Wilhelmy-plate-method (WPM). The working hypothesis is that the equilibrium between water and water vapor depends on the matric potential. Having the same pore and the same water content water repellency affects the soil water potential. Therefore the hydrophobized soil will change the equilibrium fractionation between water and water vapor. Hence, the contact angle between adsorbed water and water vapor is related to isotope effects

On the energy demands of small appliances in homes

Understanding the use of electrical appliances in households is crucial for improving the accuracy of electricity and energy loads forecasts. In particular, bottom-up techniques provide a powerful tool, not only for predicting demands considering socio-demographic characteristics of the occupants, but also to better resolve and implement demand side management strategies in homes. With this purpose, a study of the temporal energy use of low-load appliances (meaning those whose annual energy share is individually negligible but relevant when considered as a group) has been carried out, with the longer term objective of finding a parsimonious approach to modelling them, and which considers an appropriate aggregation of appliances. In this work, a discrete-time stochastic process has been implemented for a specific classification of low-load appliances. More precisely, a time-inhomogeneous Markov chain has been used to model energy variations over time for four different categories of appliances and its prediction capabilities have been tested and compared

Macchine da pressofusione Vacural Müller Weingarten

In questo articolo viene presentata una panoramica della macchina da pressocolata tipo “Vacural”prodotta dall’azienda tedesca Müller Weingarten. Questo tipo di impianto è stato inventato per produrregetti di pressocolati con alto vuoto: con questa tecnologia vengono eliminate le porosità all’interno deigetti. Le macchine da presso colata Vacural sono in uso in molte aziende che lavorano in particolare nelsettore dell’automotive. Una delle più importanti applicazioni degli impianti Vacural è nello stampaggiodello “space frame” di alcune autovetture

Eine neue Methode zur in-situ Bestimmung von präferentiellen Fließwegen von Wasser im Boden

Böden zeigen in der Regel, auch auf sehr kleinem Raum, eine große Variabilität der hydraulischen Eigenschaften. Diese Eigenschaften, aber auch verschiedene Rand- und Anfangsbedingungen oder andere Bodeneigenschaften, können zu einer räumlich und zeitlich unterschiedlichen Verlagerung von Wasser und damit transportierten Stoffen führen (preferential flow). Diese präferentiellen Flüsse werden in der Regel nicht bei der Vorhersage des Wasser- und Stofftransportes berücksichtigt und können daher starke Abweichungen vom prognostizierten Wasser- und Stofftransport verursachen. Präferentielle Flüsse sind an eine bestimmte räumliche Skala gebunden. Auf der Profilskala auftretende präferentielle Flüsse können i. d. R. nicht an Stechzylinderproben im Labor gemessen werden. Deshalb wird eine neue Feldmethode vorgestellt, bei der präferentiell fließendes Wasser in-situ detektiert werden kann. Mit Hilfe einer Beregnungsanlage wird Wasser mit einer konstanten Rate auf einer Fläche von ca. 8 m2 verregnet. Wassergehalte und –spannungen werden mit TDR-Sonden und Tensiometern kurz unter der Bodenoberfläche gemessen. Die Einstellung des Fließgleichgewichtes kann an der Konstanz der Wassergehalte und –spannungen detektiert werden. Die gleichmäßige, kurzzeitige Verregnung eines Salztracers wird durch die Messung der elektrischen Leitfähigkeit des Bodenwassers mit den TDR-Sonden erfasst werden. Mit Hilfe dieses Pulses können lokale Fließgeschwindigkeiten und somit präferentielle Fließwege aufgezeigt werden. Untermauert werden die Ergebnisse des Beregnungsversuches mit weiteren in-Situ- und Labormessungen der hydraulischen Leitfähigkeit und Simulationsmodellen. Mit der vorgestellten Methode konnten präferenzielle Wasserflüsse im Boden auch bei unterschiedlichen Anfangs- und Randbedingung beobachtet werden und so zu einem besseren Prozessverständnis beitragen

Performance Bottlenecks in Digital Movie Systems

Digital movie systems offer great perspectives for multimedia applications. But the large amounts of data involved and the demand for isochronous transmission and playback are also great challenges for the designers of a new generation of file systems, database systems, operating systems, window systems, video encoder/decoder and networks. Today's research prototypes of digital movie systems suffer from severe performance bottlenecks, resulting in small movie windows, low frame rates or bad image quality (or all of these!). We consider the performance problem to be the most important problem with digital movie systems, preventing their widespread use today. In this paper we address performance issues of digital movie systems from a practical perspective. We report on performance experience gained with the XMovie system and new algorithms and protocols to overcome some of these bottlenecks