scholarly journals Inherited structure of amorphous matter

2017 ◽  
Vol 66 (17) ◽  
pp. 176405
Author(s):  
Wu Zhen-Wei ◽  
Li Mao-Zhi ◽  
Xu Li-Mei ◽  
Wang Wei-Hua
Keyword(s):  
Amorphous Matter

scholarly journals Determination of amorphous matter in industrial minerals with X-ray diffraction using Rietveld refinement.

2020 ◽  
Vol 56 (1) ◽  
pp. 1
Author(s):  
George Christidis ◽  
Katerina Paipoutlidi ◽  
Ioannis Marantos ◽  
Vasileios Perdikatsis
Keyword(s):  
Particle Size ◽  
Rietveld Refinement ◽  
Raw Materials ◽  
Internal Standard ◽  
Absolute Error ◽  
Matter Content ◽  
Size Difference ◽  
X Ray Diffraction ◽  
X Ray ◽  
Amorphous Matter

A great variety of fine grained industrial rocks, which are valued by the industry contain variable amounts of amorphous or poorly crystalline matter, which is not easily detectable by the conventional mineralogical analysis methods based on X-ray diffraction (XRD). The quantification of amorphous matter in industrial rocks is a major task because it provides a thorough characterization of the raw materials and assists to interpret their reactivity. Among the most reliable methods used for quantification of amorphous matter, are those which are based on Rietveld refinement. In this study we prepared 1:1 mixtures of synthetic or natural calcite and quartz with 5-80% glass flour and added corundum (α-Al2O3) internal standard and applied the Autoquan2.80 © software based on the BGMN computer code to quantify the amorphous matter content. The mixtures with synthetic minerals yielded results with minimum absolute error due to the similar particle size of the minerals, the internal standard and the glass. By contrast, the mixtures with natural minerals displayed greater relative error due to the particle size difference between the minerals on the one hand and the internal standard and the glass on the other, due to the microabsorption effect. Moreover, preferred orientation was important in the case of natural calcite, due to perfect  cleavage plane. Mixtures containing up to 25% amorphous matter did not display the characteristic hump at 20-30 °2θ, suggesting that the lack of the hump is not a safe criterion for the recognition of amorphous matter.

Modeling NMR Chemical Shifts in Polymers and Amorphous Matter

1999 ◽  
pp. 24-39 ◽  
Author(s):  
Isao Ando ◽  
Shigeki Kuroki ◽  
Hiromichi Kurosu ◽  
Masahito Uchida ◽  
Takeshi Yamanobe
Keyword(s):  
Chemical Shifts ◽  
Nmr Chemical Shifts ◽  
Amorphous Matter

scholarly journals Topological Weaire–Thorpe models of amorphous matter

2020 ◽  
Vol 117 (48) ◽  
pp. 30260-30265 ◽  
Author(s):  
Quentin Marsal ◽  
Dániel Varjas ◽  
Adolfo G. Grushin
Keyword(s):  
Coordination Number ◽  
Amorphous Solids ◽  
Real Space ◽  
Complete Classification ◽  
Spectral Gaps ◽  
Topological Materials ◽  
Covalently Bonded ◽  
Topological States ◽  
Amorphous Matter

Amorphous solids remain outside of the classification and systematic discovery of new topological materials, partially due to the lack of realistic models that are analytically tractable. Here we introduce the topological Weaire–Thorpe class of models, which are defined on amorphous lattices with fixed coordination number, a realistic feature of covalently bonded amorphous solids. Their short-range properties allow us to analytically predict spectral gaps. Their symmetry under permutation of orbitals allows us to analytically compute topological phase diagrams, which determine quantized observables like circular dichroism, by introducing symmetry indicators in amorphous systems. These models and our procedures to define invariants are generalizable to higher coordination number and dimensions, opening a route toward a complete classification of amorphous topological states in real space using quasilocal properties.

Ejaculate-storage patterns and the site of fertilization in female snow crabs (Chionoecetes opilio; Brachyura, Majidae)

2000 ◽  
Vol 78 (11) ◽  
pp. 1902-1917 ◽  
Author(s):  
Guy Sainte-Marie ◽  
Bernard Sainte-Marie ◽  
Jean-Marie Sévigny
Keyword(s):  
Microscopy Study ◽  
Sperm Precedence ◽  
Single Male ◽  
Chionoecetes Opilio ◽  
Intermediate Chamber ◽  
Snow Crabs ◽  
Multiple Male ◽  
Storage Patterns ◽  
Basic Configuration ◽  
Amorphous Matter

A light-microscopy study of mated female snow crabs (Chionoecetes opilio) was conducted to investigate the site of fertilization and to resolve how multiple ejaculates are stored in the spermathecae. In its basic configuration, an ejaculate consisted of a layer or patch of spermatophores enclosing mature spermatids that was capped by a relatively large volume of amorphous matter, which in turn could include a patch of spermatophores containing immature spermatids. Up to 10-12 ejaculates were stored in the spermathecae with the largest loads. An ejaculate was initially deposited in the intermediate chamber and ventral part of the spermatheca, and was displaced toward the dorsal part of the spermatheca when a new ejaculate was inserted. Ejaculates were neatly stratified along the ventrodorsal axis of spermathecae with small to moderate loads, but they were disrupted and the storage pattern was disorderly in spermathecae with large loads. Ejaculate stratification favors last-male sperm precedence and single-male paternity. However, multiple-male paternity might occur in females with large spermathecal loads, in part because several ejaculates can co-occur close to the oviduct opening. Mixing of male and female gametes in preparation for oviposition, and probably also fertilization, occurs to some degree in the ovaries.

Production of Nanosilica from Iron Tailing and Characterization

2011 ◽  
Vol 295-297 ◽  
pp. 282-285
Author(s):  
Feng Feng Li ◽  
Ming Xi Zhang ◽  
Yi Shen ◽  
Du Jiao ◽  
Gui Qin Hou ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
High Temperature ◽  
Silicon Dioxide ◽  
Chemical Deposition ◽  
Deposition Method ◽  
Analysis Techniques ◽  
Chemical Deposition Method ◽  
Ft Ir ◽  
Thermal Analysis Techniques ◽  
Amorphous Matter

Nanosilica was extracted from iron tailing by the chemical deposition method, involving pickling, filters washing, alkali dissolving of pickling dregs in high temperature, precipitating silica controlled by diluted acid and so on. The product has been studied by SEM, XRD, FT-IR, and thermal analysis techniques, etc. These study shows that the nanosilica is a kind of amorphous matter consists of hydrous silicon dioxide (97.076%) with small amount of sodium and aluminum trapped inside the Si–O network. The diameter of globular silica particles is 30-50 nm.

In Silico Prediction of Drug Solubility. 3. Free Energy of Solvation in Pure Amorphous Matter

2007 ◽  
Vol 111 (25) ◽  
pp. 7303-7311 ◽  
Author(s):  
Kai Lüder ◽  
Lennart Lindfors ◽  
Jan Westergren ◽  
Sture Nordholm ◽  
Roland Kjellander
Keyword(s):  
Free Energy ◽  
In Silico ◽  
Drug Solubility ◽  
In Silico Prediction ◽  
Free Energy Of Solvation ◽  
Amorphous Matter

scholarly journals Quantitative Analysis of Portland Cement Clinker with Rietveld Refinement: Implications of the Amorphous Matter

2021 ◽  
Vol 5 (1) ◽  
pp. 75
Author(s):  
Georgios E. Christidis ◽  
Maria Dimitriadi ◽  
George Triantafyllou ◽  
Christos Tsoumeleas
Keyword(s):  
Portland Cement ◽  
Rietveld Method ◽  
Internal Standard ◽  
Complete Characterization ◽  
Cement Clinker ◽  
White Cement ◽  
Portland Cement Clinker ◽  
Amorphous Matter

Six ordinary Portland cement (OPC) clinkers and one white cement clinker were analyzed with the Rietveld method, using ZnO internal standard (IC), to determine the presence of amorphous matter (AM). All clinkers contain abundant AM and have lower silicate phase contents when compared with the same clinkers analyzed without IC, whereas the abundances of the aluminate and ferrate phases were not affected by AM. The white cement clinker had the highest AM content. Determination of AM is important for complete characterization of the OPC clinker and might contribute to a better understanding of the mechanical properties of the clinker.

scholarly journals Alkali-Aggregate Reaction: A study of the influence of the petrographic characteristics of volcanic rocks

2018 ◽  
Vol 8 (1) ◽  
pp. 2399-2404
Author(s):  
F. Tiecher ◽  
M. B. Gomes ◽  
D. C. C. Dal Molin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Chemical Composition ◽  
Volcanic Rocks ◽  
Degree Of Crystallinity ◽  
Mineral Phases ◽  
Alkali Aggregate Reaction ◽  
The Degree Of Crystallinity ◽  
Scanning Electron ◽  
Amorphous Matter

When the rock involved in the alkali-aggregate reaction (AAR) is volcanic, the matter present in the interstices of the grains, called mesostasis is considered responsible for the expansions. Mesostasis is a residue which consists of mineral phases rich in silica and alkalis (K and Na) and in optical microscopy looks like amorphous matter. By means of scanning electron microscopy (SEM) and with the aid of energy dispersive spectroscopy (EDS), the presence of well-crystallized mineral phases in mesostasis can be observed. The objective of this study was to evaluate the amount, the chemical composition and the degree of crystallinity of mesostasis on the reactive potentiality of volcanic rocks.

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