THE KINETICS OF THE REACTION OF SILICA WITH GROUP I HYDROXIDES

1961 ◽  
Vol 39 (6) ◽  
pp. 1221-1230 ◽  
Author(s):  
J. G. Hooley
Keyword(s):  
Silica Glass ◽  
Maximum Rate ◽  
Inverse Function ◽  
Ammonium Ion ◽  
Water Addition ◽  
Group I ◽  
Hydroxyl Ion ◽  
Naoh Solution ◽  
Ion Size ◽  
Glass Surfaces

A method is presented for preparing a reproducible silica glass or quartz surface that does not craze during rate of solution measurements in solutions of the five group I hydroxides. For silica glass, initial rates are a maximum at 8 M for at least NaOH and KOH and are an inverse function of ion size for the five cations and tetramethyl ammonium ion. A proposed mechanism of water addition followed by reaction with hydroxyl ion is used to explain the maximum rate and the effect of solution products and the substitution of methanol for water as a solvent. For quartz an explanation is offered for the lower rate and for the absence of a maximum rate below 27 M NaOH. A common temperature coefficient of 20 kcal mole−1 is reported for all reactions in water. The crazing of finely ground or polished silica glass surfaces is related to the presence of surface cracks and their enlargement by possible conversion of some silica to quartz in NaOH solution.

An electron spin resonance study of ultraviolet photolyzed methanol adsorbed on porous high-silica glass

1969 ◽  
Vol 47 (8) ◽  
pp. 1375-1379 ◽  
Author(s):  
Michie Shimizu ◽  
H. D. Gesser ◽  
M. Fujimoto
Keyword(s):  
Free Radicals ◽  
Electron Spin Resonance ◽  
Electron Spin ◽  
Silica Glass ◽  
Electron Spin Resonance Study ◽  
Surface Contaminants ◽  
Spin Resonance ◽  
High Silica ◽  
Glass Surfaces ◽  
Spin Resonance Study

The electron spin resonance (e.s.r.) spectra of •CH3, •CHO, H and/or D, and possibly •CH2OH or •CH2OD were found by the ultraviolet (u.v.) photolysis of methanol —OH or —OD on porous high-silica glass at 77 °K. These e.s.r. spectra resemble the results of the u.v. photolysis of X-irradiated methanol indicating that some perturbation and/or sensitization occurred in the molecules by the glass surface. The absence of e.s.r. spectra from the same systems on the acid-leached glass, on the totally fluorinated glass, or on the totally —OH covered glass suggests that (i) the co-existence of surface contaminants, such as Al and Zr and not B, and some of surface —OH could be responsible for producing these free radicals, and (ii) the methanols adsorbed on these glass surfaces are stabilized against u.v. photolysis.

A Fundamental Investigation of Electrochemical Preparation of Battery Grade Nickel Hydroxide

2010 ◽  
Vol 117 ◽  
pp. 15-20 ◽  
Author(s):  
Baladev Ash ◽  
Raja Kishore Paramguru ◽  
Barada Kanta Mishra
Keyword(s):  
Current Density ◽  
Nickel Hydroxide ◽  
Direct Relationship ◽  
Ammonium Ion ◽  
Water Molecules ◽  
Electrochemical Studies ◽  
Electrochemical Preparation ◽  
Fundamental Investigation ◽  
Hydroxyl Ion ◽  
Size And Structure

Electrochemical studies on nickel hydroxide have shown that three reduction reactions take place simultaneously at the cathode to reduce nitrate to nitrite, nitrite to ammonium ion and nitrate to ammonium ion. All the three reactions produce hydroxyl ion which raise pH to a level favorable to precipitate Ni(OH)2. Current density, which regulates flow of OH- supply, has prominent effect on the process and products. It determines whether α- or β-Ni(OH)2 would be precipitated and has a direct relationship with size and structure of the product and also with the associated water molecules. Replacement of Ti anode with consumable Ni sheet remarkably improves current efficiency (production rate) and decreases power consumption.

scholarly journals Hydroxyl-concentration distribution near the binding interface formed by heating contacted flat silica glass surfaces at high temperature

2009 ◽  
Vol 117 (1362) ◽  
pp. 211-213 ◽  
Author(s):  
Nobu KUZUU ◽  
Hideharu HORIKOSHI ◽  
Akihide OKAZAKI ◽  
Tomoya SEKI ◽  
Mitsuya TANAKA
Keyword(s):  
High Temperature ◽  
Silica Glass ◽  
Concentration Distribution ◽  
Binding Interface ◽  
Glass Surfaces

scholarly journals The onset of optical breakdown in KrF-laser-irradiated silica glass surfaces

2002 ◽  
Vol 197-198 ◽  
pp. 50-55 ◽  
Author(s):  
Y Kawaguchi ◽  
A Narazaki ◽  
T Sato ◽  
H Niino ◽  
A Yabe ◽  
...  
Keyword(s):  
Silica Glass ◽  
Optical Breakdown ◽  
Krf Laser ◽  
Glass Surfaces

Smoothing of Silica Glass Surfaces by Ion Implantation

1991 ◽  
Vol 30 (Part 1, No. 8) ◽  
pp. 1854-1859 ◽  
Author(s):  
Keiji Oyoshi ◽  
Takashi Tagami ◽  
Shuhei Tanaka
Keyword(s):  
Ion Implantation ◽  
Silica Glass ◽  
Glass Surfaces
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