Results 21 to 30 of about 9,098 (128)

Incorporation of H_2 in vitreous silica, qualitative and quantitative determination from Raman and infrared spectroscopy [PDF]

, 1998
Incorporation mechanisms of H_2 in silica glass were studied with Raman and infrared (IR) microspectroscopy. Hydrogenated samples were prepared at temperatures between 800 deg C and 955 deg C at 2 kbar total pressure.
Bény, Jean-Michel, Holtz, François, Schmidt, Burkhard C.   +2 more
core   +2 more sources

Carbonate sedimentology: An evolved discipline

The Depositional Record, EarlyView.
Abstract Although admired and examined since antiquity, carbonate sediment and rock research really began with Charles Darwin who, during a discovery phase, studied, documented and interpreted their nature in the mid‐19th century. The modern discipline, however, really began after World War II and evolved in two distinct phases.
Noel P. James, Peir K. Pufahl
wiley   +1 more source

Silica in Protoplanetary Disks

, 2008
Mid-infrared spectra of a few T Tauri stars (TTS) taken with the Infrared Spectrograph (IRS) on board the Spitzer Space Telescope show prominent narrow emission features indicating silica (crystalline silicon dioxide).
A. Li, A. R. Basu, Alexander, Armus, B. A. Sargent, Barkume, Barsony, Benzerara, Binns, Bohren, Bouvier, Bowen, Bowen, Brearley, C. J. Bohac, C. Tayrien, Calvet, Calvet, Chen, Chiar, Cohen, D'Alessio, D'Alessio, D. M. Watson, de Pater, de Zeeuw, Dodd, Dorschner, E. Furlan, Edgar, Emery, Fabian, Furlan, G. C. Sloan, Grün, Hanner, Harker, Harker, Heaney, Hemley, Henning, Herbig, Honda, Houck, J. D. Green, Jaeger, K. H. Kim, Kamp, Kastner, Kemper, Kimura, Klein, Koike, Li, Li, Luhman, Luhman, M. K. McClure, Marshall, Metchev, Mikouchi, Mutschke, Norton, P. Manoj, Palik, Pascucci, Pilipp, Plyusnina, Posch, Prato, Preibisch, Reipurth, Rietmeijer, Rietmeijer, Rietmeijer, Sargent, Schaefer, Silverstone, Tuttle, Uchida, W. J. Forrest, Werner, Wilking   +82 more
core   +1 more source

Evidence From Microscopy and U–Pb Geochronology as a Clue to the Influence of the Cretaceous Magmatism in the Diagenesis of Pre‐Salt Carbonate Reservoirs in the Santos Basin (Brazil)

Geological Journal, EarlyView.
Carbonates from Santos Basin revealed U–Pb ages correlated with basalt ages (A), suggesting that they were formed during magmatic events. These events placed hot CO2 in the reservoir, which, when mixed with carbonate‐rich cold water (B), led to thermal convection, enabling the formation of the U contained in the carbonates.
Marco António Ruivo de Castro e Brito, Cristiano Leite Sombra, Davy Raeder Brandão, Cleverson Guizan Silva, Sidney Luiz de Matos Mello, Eugênio Vaz dos Santos Neto, Rui Jorge Fernandes Baptista, Ramsés Capilla, Luiz Antônio Pierantoni Gambôa   +8 more
wiley   +1 more source

Integrating rotational components to optical properties observed in petrographic thin sections via automated image acquisition and analysis

Mineralogia
The analysis of petrographic thin sections is a widely used process for the identification of the mineralogy of rocks and the analysis of their textural and microstructural characteristics.
Pretorius Jacob Johannes, Mayne Matthew Jason   +1 more
doaj   +1 more source

Optical properties of cosmic dust analogs: A review

, 2010
Nanometer- and micrometer-sized solid particles play an important role in the evolutionary cycle of stars and interstellar matter. The optical properties of cosmic grains determine the interaction of the radiation field with the solids, thereby ...
Henning, Thomas, Mutschke, Harald
core   +1 more source

“Flames Over Persepolis”: New Scientific Evidence Supporting Historical Perspectives

Archaeometry, EarlyView.
ABSTRACT This study investigates the burning of Persepolis Terrace, historically attributed to Alexander III in 330 bce. A review of classical accounts and excavation reports, combined with diagnostic surveys, confirms the fire's historicity and provides novel insights.
Maria Letizia Amadori, Ileana De Giuseppe, Fabrizio Frontalini, Luca Pellegrino, Richard W. Jordan, Pierfrancesco Callieri, Emad Matin, Alireza Askari Chaverdi, Hamid Fadaei, Valeria Mengacci, Fulvio Fantino   +10 more
wiley   +1 more source

Structural and compositional properties of brown dwarf disks: the case of 2MASS J04442713+2512164 [PDF]

, 2008
In order to improve our understanding of substellar formation, we have performed a compositional and structural study of a brown dwarf disk. We present the result of photometric, spectroscopic and imaging observations of 2MASS J04442713+2512164, a ...
A. Bayo, Alencar, Apai, Appenzeller, B. Lefort, Baraffe, Barrado y Navascués, Basri, Bockelée-Morvan, Bouwman, C. Pinte, Cabrit, Calvet, Chiang, Ciesla, Comerón, D. Barrado y Navascués, Devillard, Dorschner, Dullemond, E. L. Martín, E. Pantin, F. Marchis, F. Ménard, Fernández, Fernández, G. Basri, G. Duchêne, G. Duvert, Gail, Garcia Lopez, Guieu, H. Bouy, Harker, Harker, Hartmann, Houck, J. Olofsson, J.-C. Augereau, J.-L. Monin, Kaito, Keller, Keller, Kemper, Kessler-Silacci, Kessler-Silacci, Knapp, Lagage, Lay, Luhman, Luhman, Luhman, Martín, Meeus, Merín, Mohanty, Molster, Muzerolle, Muzerolle, Muzerolle, N. Huélamo, Natta, Nuth, Ochsenbein, Pantin, Pinte, Pinte, S. Bottinelli, S. Guieu, Sargent, Scholz, Tozzi, van Boekel, van Boekel, Vogt, Walker, Whelan, White   +77 more
core   +4 more sources

Shock effects in plagioclase feldspar from the Mistastin Lake impact structure, Canada [PDF]

, 2015
Shock metamorphism, caused by hypervelocity impact, is a poorly understood process in feldspar due to the complexity of the crystal structure, the relative ease of weathering, and chemical variations, making optical studies of shocked feldspars ...
Flemming, Roberta L., Osinski, Gordon R., Pickersgill, Annemarie E.   +2 more
core   +1 more source

The nature and formation of silica minerals in eucrite meteorites: Insight into the protoplanetary magma crystallization

Meteoritics &Planetary Science, EarlyView.
Abstract Silica polymorphs in meteorites provide critical constraints on crystallization processes associated with thermal activity in the early solar system. A detailed investigation of silica polymorphs in eucrites (the largest group of achondrites) using cathodoluminescence imaging and laser‐Raman spectroscopy revealed significant variations in the ...
Rei Kanemaru, Akira Yamaguchi, Naoya Imae, Ryoga Maeda, Makoto Kimura, Kenji Horie, Takashi Mikouchi, Masaaki Miyahara, Masahiro Yasutake, Atsushi Takenouchi, Haruka Ono, Aiko Nakato, Junko Isa, Tomohiro Usui, Hirotsugu Nishido   +14 more
wiley   +1 more source