The Crystal Structures of Some Phases of Silica

The Crystal Structures of Some Phases of Silica PDF Author: Wayne Alton Dollase
Publisher:
ISBN:
Category :
Languages : en
Pages : 256

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The Crystal Structures of Some Phases of Silica

The Crystal Structures of Some Phases of Silica PDF Author: Wayne Alton Dollase
Publisher:
ISBN:
Category :
Languages : en
Pages : 256

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Book Description


Silica

Silica PDF Author: Peter J. Heaney
Publisher: Walter de Gruyter GmbH & Co KG
ISBN: 1501509691
Category : Science
Languages : en
Pages : 624

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Book Description
Volume 29 of Reviews in Mineralogy provides an updated silica review which focuses on the most recent developments. This book describes the crystal structures and phase transitions of silica and its stuffed derivatives; bridges the relationship between the microstructural character of real silica minerals and the behavior of silica in the geological environment; covers Quantum mechanical considerations of the Si-O bond; shows how calculations based upon first-principles theory can explain and predict silica transitions at high temperatures and pressures; covers spectroscopic analyses of silica and how they reveal vibrational behaviors in response to variations in temperature, pressure, and composition and finally details the uses of silica for industrial purposes.

Relationships Between Crystal Structure and Thermodynamic Parameters of Silica Phases

Relationships Between Crystal Structure and Thermodynamic Parameters of Silica Phases PDF Author: P. Vieillard
Publisher:
ISBN:
Category :
Languages : en
Pages : 26

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Crystalline Silica Overview

Crystalline Silica Overview PDF Author: Sarkis G. Ampian
Publisher:
ISBN:
Category : Silica
Languages : en
Pages : 36

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Book Description
In 1987, the International Agency for Research Against Cancer conducted a review of the health literature and concluded that crystalline silica was a probable human carcinogen. As a result of this finding, OSHA was required to regulate crystalline silica under its Hazard Communication Standard (HCS). The standard requires that all materials handled by OSHA-regulated facilities be labeled according to the requirements of HCS and that workers receive proper training on the handling of the material if the crystalline silica content equals or exceeds 0.1 weight percent (0.1%). MSHA currently is considering enacting its own HCS. This will be similar to OSHA's HCS. If the standard is enacted, most mineral producers will have to determine the respirable monitor filter and bulk crystalline silica contents of their ores and products so that workers and/or customers will know whether they are in compliance with the 0.1% HCS and/ or the OSHA permissible exposure level (PEL) of 50 micro-g for an 8-hour workday for respirable crystalline silica as determined from monitor samples. Two major concerns with the HCS are the widespread occurrence of crystalline silica in nature and the suitability of current technology for routinely determining crystalline silica concentrations at the 0.1% HCS level. Most ores are extracted from silica-bearing deposits, and silica is a common constituent of rocks and soils. OSHA's HCS will have the greatest impact on the producers of crushed stone, diatomite, dimension stone, gravel, industrial sand, perlite, pumice, pyrophyllite, sand, and talc because these materials frequently are shipped directly from the mill to the customer. MSHA's HCS would affect nearly all mineral producers. Those producers that have crystalline silica present in concentrations near the 0.1% cutoff point will have the most difficulty with the analysis. Crystalline silica can be quantified at the 0.1% level by X-ray difractometry in simple systems containing one, two, and possibly three minerals if (l) none of the accessory minerals has X-ray diffraction reflections that coincide or overlap with those of crystalline silica and (2) the standard has a particle size distribution and crystallinity similar to those of the sample. In some instances, it may not be possible to determine the crystalline silica content of a sample with any degree of certainty using the recommended regulatory protocol. In all cases, it is recommended that a qualified mineralogist identify the minerals in a sample prior to any regulatory analysis. Additionally, the uncertainty as to whether some silica polymorphs should be classified as crystalline or noncrystalline and the suitability of metastable high-temperature standards, such as cristobalite and tridymite, for regulatory analysis at ambient temperatures should be addressed further. This overview is written both to highlight these problems and to serve as a guide for analysts, regulators, and industry personnel who are involved in the crystalline silica issue. It also covers some of the difficulties and/or shortcomings in quantifying crystalline silica, such as the ubiquitous mineral quartz, in the workplace.

Introduction to Crystal Growth and Characterization

Introduction to Crystal Growth and Characterization PDF Author: Klaus-Werner Benz
Publisher: John Wiley & Sons
ISBN: 3527684344
Category : Technology & Engineering
Languages : en
Pages : 559

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Book Description
This new textbook provides for the first time a comprehensive treatment of the basics of contemporary crystallography and crystal growth in a single volume. The reader will be familiarized with the concepts for the description of morphological and structural symmetry of crystals. The architecture of crystal structures of selected inorganic and molecular crystals is illustrated. The main crystallographic databases as data sources of crystal structures are described. Nucleation processes, their kinetics and main growth mechanism will be introduced in fundamentals of crystal growth. Some phase diagrams in the solid and liquid phases in correlation with the segregation of dopants are treated on a macro- and microscale. Fluid dynamic aspects with different types of convection in melts and solutions are discussed. Various growth techniques for semiconducting materials in connection with the use of external field (magnetic fields and microgravity) are described. Crystal characterization as the overall assessment of the grown crystal is treated in detail with respect to - crystal defects - crystal quality - field of application Introduction to Crystal Growth and Characterization is an ideal textbook written in a form readily accessible to undergraduate and graduate students of crystallography, physics, chemistry, materials science and engineering. It is also a valuable resource for all scientists concerned with crystal growth and materials engineering.

The Phases of Silica

The Phases of Silica PDF Author: Robert Browning Sosman
Publisher:
ISBN:
Category : Silica
Languages : en
Pages : 408

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Structural Chemistry of Silicates

Structural Chemistry of Silicates PDF Author: F. Liebau
Publisher: Springer Science & Business Media
ISBN: 3642500765
Category : Science
Languages : en
Pages : 484

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Book Description
As natural minerals, silica and silicates constitute by far the largest part of the earth's crust and mantle. They are equally important as raw materials and as mass produced items. For this reason they have been the subject of scientific research by geoscientists as well as by applied scientists in cement, ceramic, glass, and other industries. Moreover, intensive fun damental research on silicates has been carried out for many years because silicates are, due to their enormous variability, ideally suited for the study of general chemical and crystallographic principles. Several excellent books on mineralogy and cement, ceramics, glass, etc. give brief, usually descriptive synopses of the structure of silicates, but do not contain detailed discussions of their structural chemistry. A number of monographs on special groups of silicates, such as the micas and clay min erals, amphiboles, feldspars, and zeolites have been published which con tain more crystal chemical information. However, no modern text has been published which is devoted to the structural chemistry of silicates as a whole. Within the last 2 decades experimental and theoretical methods have been so much improved to the extent that not only have a large number of silicate structures been accurately determined, but also a better under standing has been obtained of the correlation between the chemical composition of a silicate and its structure. Therefore, the time has been reached when a modern review of the structural chemistry of silicates has become necessary.

Structure and Chemistry of Crystalline Solids

Structure and Chemistry of Crystalline Solids PDF Author: Bodie Douglas
Publisher: Springer Science & Business Media
ISBN: 0387366873
Category : Technology & Engineering
Languages : en
Pages : 356

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Book Description
Understandable by anyone concerned with crystals or solid state properties dependent on structure Presents a general system using simple notation to reveal similarities and differences among crystal structures More than 300 selected and prepared figures illustrate structures found in thousands of compounds

Crystal Chemistry of Tetrahedral Structures

Crystal Chemistry of Tetrahedral Structures PDF Author: Erwin Parthé
Publisher: CRC Press
ISBN: 9780677007007
Category : Science
Languages : en
Pages : 190

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Structure and Dynamics

Structure and Dynamics PDF Author: Martin T. Dove
Publisher: Oxford University Press
ISBN: 9780198506782
Category : Science
Languages : en
Pages : 364

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Book Description
This book describes how the arrangement and movement of atoms in a solid are related to the forces between atoms, and how they affect the behaviour and properties of materials. The book is intended for final year undergraduate students and graduate students in physics and materials science.