Results 81 to 90 of about 381,696 (284)
Experimental study of amorphous silicate formation
, 2003 Broad infrared bands at 10 and 18 μm have often been observed around oxygen-rich evolved stars, and these are thought to arise from amorphous silicate dust grains.
J. Watanabe +3 more
core +1 more source
Geological Journal, EarlyView.Petrography, thermobarometry, and pseudosection modelling reveal peak metamorphic conditions of 3–7.5 kbar and 520°C–800°C in Tonian‐Cryogenian orthogneisses of the Dom Feliciano Belt. Metamorphic field gradients of 27°C/km–39°C/km and variable exhumation mechanisms support correlation of these units as remnants of a Himalayan‐type Piratini Orogeny ...
Thaiane Niederauer‐Santos +6 more
wiley +1 more source
A Steep-extinction Quasi-stellar Object at z = 4.6: JWST Evidence for Abundant Small Dust Grains
The Astrophysical Journal LettersThe rapid accumulation of massive dust reservoirs in the early Universe remains a major challenge in astrophysics. While core-collapse supernovae can inject large dust grains ( a ≳ 0.1 μ m) on short timescales, explaining the total dust budgets in the ...
Mingyu Li +11 more
doaj +1 more source
The CH carbonaceous chondrites contain a population of ferrous (Fe/(Fe + Mg) approximate to 0.1-0.4) silicate spherules (chondrules), about 15-30 mum in apparent diameter, composed of cryptocrystalline olivine-pyroxene normative material, +/-SiO2-rich ...
Zolensky, M.E. +7 more
core +1 more source
Geological Journal, EarlyView.In this study, we re‐examine the depositional architecture of the Erfoud limestone in Morocco. Introducing new biostratigraphic constraints from chitinozoan assemblages, we show that Katian to Hirnantian bryozoan‐pelmatozoan meadows reflect flooding events linked to a series of interglacial transgressions known to have occurred immediately prior to the
Philippe Razin +4 more
wiley +1 more source
CO2 Infrared Spectra on Silicate Dust Grain Analogs: Implications for JWST Observations
The Astrophysical Journal LettersCarbon dioxide is one of the three most abundant species within the ice mantles around dust grains inside molecular clouds. Since a substantial number of interstellar grains are made of siliceous materials, we have studied the infrared profile of CO _2 ...
Tushar Suhasaria +4 more
doaj +1 more source
Journal of Chemical Technology &Biotechnology, EarlyView.Abstract BACKGROUND The continuous discharge of organic dyes into freshwater poses long‐term environmental risks. Heterogeneous Fenton‐like processes using iron (Fe)‐modified silica (SiO2) supports are promising for dye removal; however, catalysts derived from natural sand and operating under near‐neutral conditions remain relatively underexplored ...
Hajer Aloulou +6 more
wiley +1 more source
Journal of Plant Nutrition and Soil Science, EarlyView.ABSTRACT Background Sewage sludge ash (SSA) is a potential phosphorus (P) source for fertilizers, but untreated SSA (USSA) often shows low plant availability of P. To increase P availability, sodium additives can be applied before sewage sludge incineration or during thermochemical SSA posttreatment, as this leads to the formation of CaNaPO4.
Kai Leers +4 more
wiley +1 more source
Journal of Quaternary Science, EarlyView.ABSTRACT Central Australia's ngarrawa, or ‘mound springs’, are unique hydrological systems that serve as some of the only near‐permanent sources of water and continuous sediment deposition in Australia's arid interior. As such, they hold significant potential as palaeo‐climate and ‐environmental archives in a region where many aspects of past climate ...
Fletcher C. Nixon +3 more
wiley +1 more source
The Astrophysical JournalThe dusty interstellar medium (ISM) of the Milky Way is distributed in a complex, cloudy structure. It is fundamental to the radiation balance within the Milky Way, provides a reaction surface to form complex molecules, and is the feedstock for future ...
S. T. Zeegers +35 more
doaj +1 more source