相关论文: Do cement nanoparticles exist in space ?
We investigated the infrared (IR) dust emission from PN IC 418, using a detailed model controlled by a previous determination of the stellar properties and the characteristics of the photoionized nebula, keeping as free parameters the dust…
The eventual presence of the diamond carbon allotrope in space is discussed in numerous theoretical and experimental studies. The review summarizes the principal mechanisms of nanodiamond formation and experimental results of spectroscopic…
The condensation of complex silicates with pyroxene and olivine composition at conditions prevailing in molecular clouds has been experimentally studied. For this purpose, molecular species comprising refractory elements were forced to…
Clustering and dynamics of nano-sized particles (nano dust) is investigated using high-resolution ($1024^3$) simulations of compressible isothermal hydrodynamic turbulence, intended to mimic the conditions inside cold molecular clouds in…
We are living in a dusty universe: dust is ubiquitously seen in a wide variety of astrophysical environments, ranging from circumstellar envelopes around cool red giants to supernova ejecta, from diffuse and dense interstellar clouds and…
Cement mineral tobermorite was formed in hydrothermal experiments on alternation of calcium-aluminum-rich inclusions (CAIs) in carbonaceous chondrite meteorites. Unidentified bands at 14 microns were measured for CAIs and the matrix of the…
Models of astrophysical dust are key to understand several physical processes, from the role of dust grains as cooling agents in the ISM to their evolution in dense circumstellar disks, explaining the occurrence of planetary systems around…
Silicate minerals belong to the most abundant solids in space. Their formation becomes difficult at the transition from the oxygen rich chemistry of M-stars to the carbon rich chemistry of C-stars. In the intermediate type S-stars oxygen…
Context. As the 4th most abundant element in the universe, carbon (C) is widespread in the interstellar medium (ISM) in various allotropic forms (e.g., fullerenes have been identified unambiguously in many astronomical environments, the…
X-ray absorption fine structure (XAFS) in the 0.2-2 keV band is a crucial component in multi-wavelength studies of dust mineralogy, size, and shape -- parameters that are necessary for interpreting astronomical observations and building…
The abundances of gas and dust (solids and complex molecules) in the interstellar medium (ISM) as well as their composition and structures impact practically all of astrophysics. Fundamental processes from star formation to stellar winds to…
Crystalline silicates are an important tracer to the dust evolution in protoplanetary disks. In the inner disk, amorphous silicates are annealed by the high temperatures. These crystalline silicates are radially and vertically distributed…
The spectral region around 10 micrometer, showing prominent dust emission bands, is commonly used to derive the chemical composition of protoplanetary dust. Different analysis methods have been proposed for this purpose, but so far, no…
Silicon Carbide (SiC) optical constants are fundamental inputs for radiative transfer models of astrophysical dust environments. However, previously published values contain errors and do not adequately represent the bulk physical…
The spectral energy distribution of quasars shows a sharp steepening of the continuum shortward of ~ 1100 A. The steepening could be a result of dust absorption. We present a dust extinction model which considers crystalline carbon grains…
This article gives an overview of the constitution, physical conditions and observables of dust in the interstellar medium of nearby galaxies. We first review the macroscopic, spatial distribution of dust in these objects, and its…
Interstellar iron in the form of metallic iron nanoparticles may constitute a component of the interstellar dust. We compute the stability of iron nanoparticles to sublimation in the interstellar radiation field, finding that iron clusters…
Carbon dioxide is one of the three most abundant species within the ice mantles around dust grains inside molecular clouds. Since a substantial amount of interstellar grains is made of siliceous materials, we have studied the infrared…
Any distortion of a chemical structure causes new features to appear in the absorption spectrum of the structure, especially in the visible and near UV (see Paper I). Chemical modeling, using molecular orbital theory, showed that the…
Since their discovery in 1991, carbon nanotubes (CNTs) -- a novel one-dimensional carbon allotrope -- have attracted considerable interest worldwide because of their potential technological applications such as electric and optical devices.…