Silicon dioxide (silica) is ubiquitous, and a variety of crystalline and amorphous silica polymorphs is known. They originate from both, natural and synthetic processes. Examples of silica polymorphs that are amorphous to X-rays are synthetically pure precipitated or fumed silica, gem opal, diatoms...
Specific features of erbium ion photoluminescence in structures with amorphous and crystalline silicon nanoclusters in silica matrix annealing of Si-rich oxide or nitride films which gives rise to the phase separation reaction and the formation of crystalline silicon nanoclusters in the ... Sergey Dyakov...
Related to Crystalline silicon: Amorphous siliconsil·i·con (sĭl′ĭ-kən, -kŏn′) n. Symbol Si A nonmetallic element occurring extensively in the earth's crust in silica and silicates, having both a brown amorphous and a gray lustrous crystalline allotrope, and used doped or in co...
硅andOtherForms无定形非结晶otherformsnon 系统标签: silicaamorphouscrystalline定形formsnon Chief Engineer’s Office TEXAS COMMISSION ON ENVIRONMENTAL QUALITY Development Support Document Final, July 29, 2011 Accessible 2013 Silica, Amorphous and Other Non-Crystalline Forms CAS Registry Numbers: 7631-86-9...
An improved catalytic process for making para-xylene from toluene and a methylating agent employing the described crystalline silica as catalyst, said catalyst optionally promoted by one or more compounds of arsenic, phosphorus, magnesium, boron, antimony and amorphous silica. Preferred promoters are bo...
Fig. 2: Helical dichroism in amorphous solids. aHD (Type I) for fused silica (blue) and borosilicate (red) as a function of displacement of the singularity with linearly polarized (ϵ = 0.05) asymmetrical OAM beam (l = ± 3).bOrientation-dependent transmission ofl = ±...
(crystalline vs. amorphous), composition (metals present in the silica, e.g., iron), or compounds that can be associated with crystalline silica (iron) can influence its bioactivity.In addition to a direct cytotoxic action, crystalline silica can activate cells to release proinflammatory and ...
Differential molar enthalpy of displacement was correlated with the experimental adsorption isotherm and plotted as a function of the amount adsorbed. The general (qualitative) shape of the enthalpy curve appears to be dependent upon the crystalline structure of silica (amorphous-crystalline). The ...
Moreover, the combination of chemical deposition and annealing avoids difficulties associated with undesired transfer of oxygen impurities to the silicon core from the molten cladding during the drawing process. The high aspect ratio of the amorphous silicon core and the presence of the silica cladding...
These minerals have a characteristic absorption band corresponding in position to the analytical peak for crystalline silica. In this paper, six typical interference minerals (Kaolinite, Mullite, Muscovite, Pyrophyllite, Montmorillonite and Amorphous silica) were pre-size controlled to respirable range and...