Recovery of Gold from Refractory Sulphide Concentrates by Means of Pressure Oxidation and Thiocyanate Leaching

1971 ◽

Vol 29 ◽

pp. 212-213

Author(s):

R. H. Geiss ◽

R. L. Ladd ◽

K. R. Lawless

Keyword(s):

High Vacuum ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Ultra High Vacuum ◽

Pure Oxygen ◽

Pressure Oxidation ◽

High Voltage Electron Microscopy ◽

Oxidation Study ◽

Voltage Electron ◽

Good Agreement

Detailed electron microscope and diffraction studies of the sub-oxides of vanadium have been reported by Cambini and co-workers, and an oxidation study, possibly complicated by carbon and/or nitrogen, has been published by Edington and Smallman. The results reported by these different authors are not in good agreement. For this study, high purity polycrystalline vanadium samples were electrochemically thinned in a dual jet polisher using a solution of 20% H2SO4, 80% CH3OH, and then oxidized in an ion-pumped ultra-high vacuum reactor system using spectroscopically pure oxygen. Samples were oxidized at 350°C and 100μ oxygen pressure for periods of 30,60,90 and 160 minutes. Since our primary interest is in the mechanism of the low pressure oxidation process, the oxidized samples were cooled rapidly and not homogenized. The specimens were then examined in the HVEM at voltages up to 500 kV, the higher voltages being necessary to examine thick sections for which the oxidation behavior was more characteristic of the bulk.

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Formation of defects in implanted hipox-structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131668 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1406-1407

Author(s):

Peter Pegler ◽

N. David Theodore ◽

Ming Pan

Keyword(s):

High Pressure ◽

Cross Section ◽

Semiconductor Devices ◽

Silicon Substrates ◽

Processing Conditions ◽

Pressure Oxidation ◽

Deep Trench ◽

Local Oxidation ◽

Trench Isolation ◽

And Behavior

High-pressure oxidation of silicon (HIPOX) is one of various techniques used for electrical-isolation of semiconductor-devices on silicon substrates. Other techniques have included local-oxidation of silicon (LOCOS), poly-buffered LOCOS, deep-trench isolation and separation of silicon by implanted oxygen (SIMOX). Reliable use of HIPOX for device-isolation requires an understanding of the behavior of the materials and structures being used and their interactions under different processing conditions. The effect of HIPOX-related stresses in the structures is of interest because structuraldefects, if formed, could electrically degrade devices.This investigation was performed to study the origin and behavior of defects in recessed HIPOX (RHIPOX) structures. The structures were exposed to a boron implant. Samples consisted of (i) RHlPOX'ed strip exposed to a boron implant, (ii) recessed strip prior to HIPOX, but exposed to a boron implant, (iii) test-pad prior to HIPOX, (iv) HIPOX'ed region away from R-HIPOX edge. Cross-section TEM specimens were prepared in the <110> substrate-geometry.

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A novel preparation process for LaCuO3 involving a high pressure oxidation of precursor derived from the perovskite structure: An appropriate route for doping with 57Fe Mössbauer probe

Solid State Sciences ◽

10.1016/j.solidstatesciences.2007.03.007 ◽

2007 ◽

Vol 9 (5) ◽

pp. 376-379 ◽

Cited By ~ 11

Author(s):

G. Demazeau ◽

A. Baranov ◽

G. Heymann ◽

H. Huppertz ◽

A. Sobolev ◽

...

Keyword(s):

High Pressure ◽

Perovskite Structure ◽

Preparation Process ◽

Pressure Oxidation ◽

57Fe Mössbauer ◽

High Pressure Oxidation

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Mass spectrometric studies of the low-pressure oxidation of methane on samarium sesquioxide

The Journal of Physical Chemistry ◽

10.1021/j100350a026 ◽

1989 ◽

Vol 93 (13) ◽

pp. 5155-5158 ◽

Cited By ~ 13

Author(s):

Valentin T. Amorebieta ◽

Agustin J. Colussi

Keyword(s):

Low Pressure ◽

Mass Spectrometric ◽

Pressure Oxidation ◽

Oxidation Of Methane

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The Effect of Ge Segregation on Oxidation of Si

MRS Proceedings ◽

10.1557/proc-105-277 ◽

1987 ◽

Vol 105 ◽

Cited By ~ 8

Author(s):

E. C. Frey ◽

N. R. Parikh ◽

M. L. Swanson ◽

M. Z. Numan ◽

W. K. Chu

Keyword(s):

High Pressure ◽

Low Temperature ◽

Epitaxial Layer ◽

Atmospheric Pressure ◽

Oxidation Rate ◽

Oxidation Temperature ◽

Pressure Oxidation ◽

Enhanced Oxidation ◽

High Pressure Oxidation

AbstractWe have studied oxidation of various Si samples including: Ge implanted Si, CVD and MBE grown Si(0.4–4% Ge) alloys, and MBE grown Si-Si(Ge) superlattices. The samples were oxidized in pyrogenic steam (800–1000°C, atmospheric pressure) and at low temperature and high pressure (740°C, 205 atm of dry O2). The oxidized samples were analyzed with RBS/channeling and ellipsometry.An enhanced oxidation rate was seen for all Ge doped samples, compared with rates for pure Si. The magnitude of the enhancement increased with decreasing oxidation temperature. For steam oxidations the Ge was segregated from the oxide and formed an epitaxial layer at the Si-SiO2 interface; the quality of the epitaxy was highest for the highest oxidation temperatures. For high pressure oxidation the Ge was trapped in the oxide and the greatest enhancement in oxidation rate (>100%) was observed.

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