Reaction rates for ozone + hydrochloric acid .fwdarw. atomic oxygen + molecular oxygen + hydrochloric acid, atomic chlorine + ozone .fwdarw. chlorine monoxide + molecular oxygen, and hydrochloric acid + atomic oxygen .fwdarw. hydroxyl + atomic chlorine at elevated temperatures

1977 ◽  
Vol 81 (6) ◽  
pp. 499-504 ◽  
Author(s):  
Chul Park
Keyword(s):  
Hydrochloric Acid ◽  
Molecular Oxygen ◽  
Atomic Oxygen ◽  
Elevated Temperatures ◽  
Reaction Rates ◽  
Chlorine Monoxide ◽  
Atomic Chlorine

Electric-Field Effects on Reactions Between Oxides

1997 ◽  
Vol 481 ◽  
Author(s):  
Matthew T. Johnson ◽  
Shelley R. Gilliss ◽  
C. Barry Carter
Keyword(s):  
Solid State ◽  
Electric Field ◽  
Elevated Temperatures ◽  
Ionic Current ◽  
Reaction Rates ◽  
Solid State Reactions ◽  
Interfacial Stability ◽  
Electric Field Effects ◽  
Thin Film Diffusion ◽  
Microscopy Techniques

ABSTRACTThin films of In2O3 and Fe2O3 have been deposited on (001) MgO using pulsed-laser deposition (PLD). These thin-film diffusion couples were then reacted in an applied electric field at elevated temperatures. In this type of solid-state reaction, both the reaction rate and the interfacial stability are affected by the transport properties of the reacting ions. The electric field provides a very large external driving force that influences the diffusion of the cations in the constitutive layers. This induced ionic current causes changes in the reaction rates, interfacial stability and distribution of the phases. Through the use of electron microscopy techniques the reaction kinetics and interface morphology have been investigated in these spinel-forming systems, to gain a better understanding of the influence of an electric field on solid-state reactions.

Scanning Tunneling Microscope Study of Etch Pits on Highly Oriented Pyrolytic Graphite Heated in an Atomic Absorption Electrothermal Analyzer

1997 ◽  
Vol 51 (12) ◽  
pp. 1896-1904 ◽  
Author(s):  
Kurt G. Vandervoort ◽  
Kristin N. McLain ◽  
David J. Butcher
Keyword(s):  
Elevated Temperatures ◽  
Pyrolytic Graphite ◽  
Reaction Rates ◽  
Surface Reactivity ◽  
Scanning Tunneling ◽  
Highly Oriented Pyrolytic Graphite ◽  
Tunneling Microscopy ◽  
Etch Pits ◽  
Pit Formation ◽  
Second Period

Scanning tunneling microscopy (STM) was used to elucidate monolayer etch pits that form on highly oriented pyrolytic graphite (HOPG) heated in an electrothermal analyzer. Pits form at elevated temperatures due to reactions between oxygen and exposed carbon edge atoms (defects) and additionally with intraplanar carbon atoms (through abstraction). Samples of HOPG without analyte or matrix modifier were placed in the depression of a pure pyrolytic graphite platform and heated by using standard analysis furnace programs. Under argon stop-flow conditions, pits form in less than a second at atomization temperatures equal to and above 1200 °C. With low argon flow rates (40 mL/min), pits formed at atomization temperatures equal to and greater than 1750 °C in less than a second. Quantitative pit formation rates were used to indicate oxygen partial pressure, which may be as high as ∼ 10−3 atm at 1200 °C. Reaction rates were used to predict surface degradation due to oxygen attack and determine that 1-μm depth normal to the surface would be removed by 200 successive 5-second-period furnace firings at 1200 °C. Implications for increases in surface reactivity and analyte intercalation are discussed.

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