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The mechanism for the formation of slip bands by the sequential activation of internal Frank-Read sources on clusters of glide planes is widely accepted. A study of slip bands produced by plastic deformation at the yield point of single crystals of α-phase CuAl alloys provides no evidence for the operation of this mechanism. The observations lead to the conclusion that the elementary primary process in these alloys involves the generation of long-range avalanches of dislocations at opposite surfaces of the crystals on adjacent clusters of glide planes by the correlated operation of surface terrace sources. Als Mechanismus zur Bildung von Gleitbandern wird allgemein die aufeinanderfolgende Aktivierung innerer Frank-Read-Quellen auf Bundeln von Gleitebenen angenommen. Eine Untersuchung der Gleitbander, die durch plastische Verformung an der Fliesgrenze von Einkristallen aus α-CuAl-Legierungen erzeugt werden, hat jedoch keinen Beweis fur die Betatigung dieses Mechanismus erbracht. Die Beobachtungen fuhren zu dem Schlus, das der elementare Primarprozes in diesen Legierungen mit der Erzeugung langreichweitiger Versetzungslawinen an gegenuberliegenden Kristalloberflachen auf benachbarten Gleitebenenbundeln durch die korrelierte Betatigung von Oberflachenterrassen-Quellen verbunden ist.

An experimental investigation was conducted on the electrochemical generation of arsine from high purity (99.9999%), vapor-deposited arsenic metal in alkaline solutions. A novel method using high-sensitivity mass spectrometry (MS) coupled to an electrochemical hydrogen calibration (MS-HC) cell was employed for quantitative analysis of gaseous products. A scheme is presented for an on-demand electrochemical generator system that can provide high-purity arsine over a wide range of concentrations and flow rates to meet the requirements for practical electronic processing applications

A mathematical model of NO formation during pulverised coal combustion was developed from a proposed kinetic mechanism involving 12 overall chemical reactions. Most significantly, the model describes the complex conversion of coal bound nitrogen compounds to NO during combustion. The predictions of the model compare favourably with literature data and are in qualitative agreement with trends observed in practical coal combustion.

Chemical reactions potentially useful for converting intractable allotropes of germania (aged hexagonal and tetragonal forms) into reactive products are investigated. The effectiveness of reactions in aqueous solutions under basic, basic-reductive, acidic-oxidative, and acidic-reductive conditions is reported in terms of germania solubilization. Solubility versus time of reaction at elevated temperatures is reported for the most effective medium, 2.5M NaOH. For six flux media, fusion reactions and respective temperatures are reported with the percentage of germania solubilized from the fused melt. Additionally, the crystalline germania materials are characterized by infrared and differential thermal analyses. Chemical procedures compatible with batch or continuous processing methods are discussed.

is studied in order to investigate the most direct and economically feasible procedures for the conversion of hexagonal (quartz-type) and tetragonal (rutile-type) GeO2 into chemically reactive products useful as Ge raw materials.

Selective photochemical oxidation of trichlorosilane, , and infrared spectroscopy are used to generate and then identify trichlorosilanol, , in silicon tetrachloride, . The , an impurity unavailable in pure form and existing normally in , as an intermediate specie in equilibrium with others, is produced quantitatively at trace levels. The chemistry of formation and subsequent reactions of the silanol in , are discussed and the infrared absorptivity of the photogenerated product is experimentally determined.