Exemple de gisements plombo-zinciferes epigenetiques dans des niveaux calcaires de sillon subsident; les mineralizations du Diois et des Baronnies

Abstract The mineralization of Diois and Baronnies (France) is examined on the individual specimen, bed, and regional levels. The mineral composition consists essentially of zinc blende, galena and pyrite with some marcasite in a calcitic gangue. Study of galena and calcite samples indicates a low temperature of deposition. Three phases of mineral concentration are hypothesized; precipitation of water-dissolved metallic ions by hydrosulfuric acid; upper Eocene deposition of lead and zinc concentrations along faults by ground water; and upper Miocene to Recent superficial alteration of the beds.

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Determination of the total cadmium, copper, lead and zinc concentrations and their labile species fraction in apple beverages by flow-through anodic stripping chronopotentiometry

Food Chemistry ◽

10.1016/j.foodchem.2016.12.092 ◽

2017 ◽

Vol 225 ◽

pp. 220-229 ◽

Cited By ~ 12

Author(s):

Dominika Jedryczko ◽

Paweł Pohl ◽

Maja Welna

Keyword(s):

Lead And Zinc ◽

Stripping Chronopotentiometry ◽

Anodic Stripping ◽

Zinc Concentrations ◽

Flow Through ◽

Copper Lead

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Cadmium, Copper, Lead and Zinc Concentrations in Female and Embryonic Pacific Sharpnose Shark (Rhizoprionodon longurio) Tissues

Bulletin of Environmental Contamination and Toxicology ◽

10.1007/s00128-014-1360-0 ◽

2014 ◽

Vol 93 (5) ◽

pp. 532-535 ◽

Cited By ~ 15

Author(s):

M. G. Frías-Espericueta ◽

N. G. Cardenas-Nava ◽

J. F. Márquez-Farías ◽

J. I. Osuna-López ◽

M. D. Muy-Rangel ◽

...

Keyword(s):

Lead And Zinc ◽

Zinc Concentrations ◽

Copper Lead

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XRD Characterization of the Structure of Graphites and Carbon Materials Obtained by the Low-Temperature Graphitization of Coal Tar Pitch

Eurasian Chemico-Technological Journal ◽

10.18321/ectj198 ◽

2015 ◽

Vol 17 (2) ◽

pp. 87 ◽

Cited By ~ 20

Author(s):

Ch.N. Barnakov ◽

G.P. Khokhlova ◽

A.N. Popova ◽

S.A. Sozinov ◽

Z.R. Ismagilov

Keyword(s):

Low Temperature ◽

Carbon Materials ◽

Coal Tar ◽

Structural Phase ◽

Coherent Scattering ◽

Amorphous Structure ◽

Coal Tar Pitch ◽

X Ray Diffraction ◽

Needle Coke ◽

The Individual

The structure of some commercial graphites and carbon materials (CMs) obtained by the low-temperature catalytic graphitization of coal tar pitch with iron salt, needle coke, foamed graphite as the catalysts has been studied. The study was performed using the X-ray diffraction technique with reflections from base plane and their decomposition into two components corresponding to the structural phases of graphite which have different XRD characteristics. Various CMs were compared with respect to the structural phase ratio, distance between polyarene layers in these phases, and sizes of the coherent scattering regions. The (004) reflection provided a better fit of some properties of graphites to the calculated XRD characteristics as compared to calculation from the (002) reflection. In the case of carbonization of coal tar pitch with investigated catalyst additions, prepared carbon materials have a higher degree of graphitization and a crystallite size greater than in the other case of carbonization of the individual pitch. The highest catalytic activity is shown by foamed graphite. It was found that the use of foamed graphite as the catalyst at 800-900 ºC produced carbon materials possessing a crystalline structure with interplanar spacing close to that in commercial graphites, while in the absence of catalyst the coal tar pitch material has an amorphous structure.

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Comparison of Three Methods for Determination of /V-Nitrosopyrrolidine in Fried Dry-Cured and Pump-Cured Bacon

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/71.3.504 ◽

1988 ◽

Vol 71 (3) ◽

pp. 504-508

Author(s):

Anthony J Malanoski ◽

Wertice J Smith ◽

Thomas Phillipo

Keyword(s):

Low Temperature ◽

Thermal Energy ◽

Validation Studies ◽

Vacuum Distillation ◽

Mineral Oil ◽

Energy Analyzer ◽

Coefficients Of Variation ◽

The Individual

Abstract Three methods, the mineral oil distillation (MOD), the dry column (DC), and a low temperature vacuum distillation (LTVD), for the determination of iV-nitrosopyrrolidine in dry-cured and pump-cured bacon were compared. Each method uses the thermal energy analyzer for the determinative step. The coefficients of variation for repeatability were 10.3% (MOD), 7.2% (DC), and 9.1% (LTVD) for the dry-cured bacon study and 8.7% (MOD), 8.5% (DC), and 7.1% (LTVD) for the pump-cured bacon study. The pooled coefficients of variation for between-method reproducibility were 11.8% for the drycured bacon and 10.8% for the pump-cured bacon. The pooled coefficients of variation for repeatability were 9.0% for the dry-cured bacon and 8.2% for the pump-cured bacon. These values compare favorably with the values from previous collaborative or validation studies of the individual methods, and the methods can be considered to be equivalent

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Effect of Nitridation and Buffer in GaN Films Grown on A-Plane (11-20) Sapphire

MRS Proceedings ◽

10.1557/proc-482-51 ◽

1997 ◽

Vol 482 ◽

Cited By ~ 2

Author(s):

D. Doppalapudi ◽

E. Iliopoulos ◽

S. N. Basu ◽

T. D. Moustakas

Keyword(s):

Low Temperature ◽

Systematic Study ◽

Optoelectronic Properties ◽

Pronounced Effect ◽

Significant Fraction ◽

Plasma Nitridation ◽

Zinc Blende ◽

Photoluminescence Studies ◽

Structural And Optoelectronic Properties

AbstractIn this paper, we report on a systematic study of GaN growth on the A-plane sapphire by plasma-assisted MBE. The effects of plasma nitridation of the substrate and the growth of a low temperature GaN buffer on the structure and optoelectronic properties of the films are addressed. TEM studies indicate that films grown on substrates which were not nitridated prior to growth have a significant fraction of zinc-blende domains and poor orientational relation with the substrate. On the contrary, nitridation leads to films with superior structural and optoelectronic properties. The low temperature GaN buffer, grown on nitridated substrates, was found to also have a pronounced effect on the optoelectronic properties of the GaN films, especially in those with low carrier concentrations. The correlation between TEM and photoluminescence studies suggest that the transition at 3.27 eV can be attributed to the cubic domains in the films.

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