Competitative adsorption of two dissolved organics onto activated carbon—II: Adsorption kinetics in batch reactors

Bi-solute adsorption of dissolved organics by activated carbon was studied in a finite bath system. The batch tests with strongly adsorbable species show that at low concentrations (X < 0.1 mmol/1) only external mass transfer resistance is rate-determining. For higher concentrations internal mass transfer becomes increasingly important. This behavior indicates that the diffusional process within the particle occurs predominantly in the adsorbed phase.Bi-solute calculations were performed, using only single-solute data. Systems with differing equilibrium behavior, but similar diffusive properties of both solutes, were described adequately by a model which takes into account diffusion in the liquid-filled pores and in the adsorbed phase, as well as external mass transfer. Deviations between measured and predicted rates can be observed for systems with large differences in the mobility of the diffusing molecules, or if counter diffusion inside the particles occurs. It is likely that the discrepancies in these cases are caused by diffusional interactions between the two different species in the adsorbed phase.     

Einfluß von Wasserdampf im Sintergas auf das Verhalten von Metallpulvern mit unter Sinterbedingungen reduzierbaren Oxydschichten

An aus Elektrolyteisen-, Karbonylnickel- und Kupferpulver hergestellten Preßkörpern Untersuchung ihres Sinterverhaltens unter Wasserstoffgas mit Zusätzen von 0,1 und 10 Vol.-% Wasserdampf bei Sintertemperaturen von 870 bis 1200 °C und Sinterdauern von 0 bis 8 h. Messung von Dichte, 0,2-Orenze, Zugfestigkeit und Bruchdehnung der Proben in Abhängigkeit vom Wasserdampfgehalt im Sintergas und dementsprechende thermochemische Deutung der Versuchsergebnisse.     

Einfluß der Schrottvorwärmung mit Erdgas und Sauerstoff im Konverter auf den Sauerstoffumsatz des LD-Verfahrens

Stand der Erkenntnisse und Ziel der eigenen Versuche. Anlagenbeschreibung und Betriebsbeobachtungen. Untersuchung der Schlackenbildung während der Schrottvorwärmung. Änderungen der Roheisenzusammensetzung durch Reaktionen mit den Vorwärmschlacken. Betrachtungen zur Sauerstoffbilanz.     

Low dimensional adaptive texture feature vectors from class distance and class difference matrices

In many popular texture analysis methods, second or higher order statistics on the relation between pixel gray level values are stored in matrices. A high dimensional vector of predefined, nonadaptive features is then extracted from these matrices. Identifying a few consistently valuable features is important, as it improves classification reliability and enhances our understanding of the phenomena that we are modeling. Whatever sophisticated selection algorithm we use, there is a risk of selecting purely coincidental "good" feature sets, especially if we have a large number of features to choose from and the available data set is limited. In a unified approach to statistical texture feature extraction, we have used class distance and class difference matrices to obtain low dimensional adaptive feature vectors for texture classification. We have applied this approach to four relevant texture analysis methods. The new adaptive features outperformed the classical features when applied to the most difficult set of 45 Brodatz texture pairs. Class distance and difference matrices also clearly illustrated the difference in texture between cell nucleus images from two different prognostic classes of early ovarian cancer. For each of the texture analysis methods, one adaptive feature contained most of the discriminatory power of the method.     

Scattering-type near-field optical microscopy

A highly promising tool for nanoscale material characterization exploits local optical/infrared light scattering simultaneously with standard atomic force microscopy imaging. Thus, both the topography and the local optical/infrared properties of a sample surface can be mapped at better than 20 nm spatial resolution.