scholarly journals Anthraxolite-Uranium Mineral: Composition, Structural Features and Genesis

2020 ◽  
Vol 5 (5) ◽  
Author(s):  
Pavel Straka
Keyword(s):  
Mineral Composition ◽  
Structural Features ◽  
Uranium Mineral

scholarly journals MINERAL COMPOSITION AND STRUCTURAL FEATURES OF JEWELER AMMONITES FROM KOSTROMA REGION

2017 ◽  
pp. 22-27 ◽  
Author(s):  
D. A. Petrochenkov
Keyword(s):  
Organic Matter ◽  
Mineral Composition ◽  
Structural Features ◽  
Electronic Microscopy ◽  
X Ray ◽  
Black Color

Detailed mineralogical examination of ammonites of jewelry quality has been carried out by means of radiographical, X-ray microanalyses and electronic microscopy. The ammonites consist mainly of calcite, apatite and some cells are constituted of phosphorite. The walls and shell’s septums consist of apatite and calcite, which have replaced original aragonite and maintain inclusions of pyrite of globular shape, aluminosilicate and organic matter. Dispersed apatite determines the black color of walls and shell’s septums. The color and transparency of the calcite, filling up the shell’s chambers, are determined by the quantity of micropores and microinclusions, mainly of apaTite. Ammonites from Kostroma region by its decorative and technology characteristics will be able to use widely in jewelry and interior articles.

scholarly journals Mineral and structural features of jewelery wood tin

2017 ◽  
pp. 36-44
Author(s):  
D. A. Petrochenkov
Keyword(s):  
Mineral Composition ◽  
Structural Features ◽  
Graphical Analysis ◽  
Electronic Probe ◽  
Tin Deposits ◽  
Native Bismuth

A mineral composition and gemological descriptions of the jewelery varieties of the wood tin of deposits Dzhalindinskoe (Khabarovskiy krai), Tynooken (East Chukotka) and Dominion Krik (Canada) have been explored. According to the data of radio-graphical analysis, wood tin consists mainly of cassiterite (76-98 mas.%). As admixtures, quartz, microcline and roentgenoamorphous phase have been found. Microinclusions of dzhalindite, preisingerite, acanthite, native bismuth, monazite and hemiatite have been found in wood tin by electronic-probe investigations. Color zonality of wood tin is defined by mineral composition, concentration of elements-admixtures (Fe, As) and microinclusions of hematite in cassiterite. Jewelery varieties of the wood tin are mainly connected with rhyolite , rarely with silicate and sulphide industrial types of tin deposits.

scholarly journals Mineral composition and gemological characteristics of jewelry-ornamental ammonites of the Republic of Adygea

2019 ◽  
pp. 32-38
Author(s):  
D. A. Petrochenkov
Keyword(s):  
Mineral Composition ◽  
Lower Cretaceous ◽  
Structural Features ◽  
Time Data ◽  
Mineral Inclusions ◽  
Technological Characteristics ◽  
Wide Range ◽  
The Republic ◽  
First Time

For the first time, data on the mineral composition and gemological characteristics of the jewelry-ornamental ammonites of the Republic of Adygea have been presented. Ammonites consist mainly of the calcite with inclusions of quartz, glauconite, kaolinite, aragonite, pyrite, apatite and hematite. The walls and partitions of the shells mainly lost the original aragonite composition and consist of calcite with inclusions of pyrite and apatite. Aragonite is preserved fragmentary in the walls and partitions of the shells. Calcite contains some elements-admixture, which average volumes, (wt. %), are: Mg0,62, Mn0,31 and Fe 1,26. The color and transparency of calcite is determined by the structural features of the crystals and mineral inclusions. Ammonites of the Republic of Adygea have a wide range of sizes and are associated with sediments of the lower Cretaceous. According to the decorative and technological characteristics ammonites can be used as a jewelry-ornamental material for the production of a wide range of ware.

scholarly journals BAMSKY GOLD DEPOSIT IN THE AMUR REGION: HISTORY OF DISCOVERY AND STUDY (FAR EAST, RUSSIA)

2021 ◽  
pp. 106-115
Author(s):  
ANTON VLADIMIROVICH MELNIKOV ◽  
◽  
VITALY ALEKSEEVICH STEPANOV ◽  
Keyword(s):  
Gold Deposit ◽  
Mineral Composition ◽  
Large Scale ◽  
Gold Mining ◽  
Far East ◽  
Mining Industry ◽  
Structural Features ◽  
Amur Region ◽  
East Russia ◽  
History Of

The materials on discovery and study of the Bamskoye gold deposit of the Amur province are given. The field was discovered in 1979 during lithogeochemical survey of 1: 200000 scale. The carried out prospecting and exploration work established a large scale of the field. An overview of publications on geological and structural features of the deposit, geochemistry and mineral composition of ores was made. It is indicated that the Bamskoye deposit may be the basis of the gold mining industry of the Amur Region for the coming decades.

scholarly journals Cummingtonite-bearing volcanic rocks: first evidence in the Central Slovak Volcanic Field

2018 ◽  
Vol 69 (4) ◽  
pp. 335-346
Author(s):  
Katarína Šarinová ◽  
Samuel Rybár
Keyword(s):  
Volcanic Rock ◽  
Mineral Composition ◽  
Volcanic Rocks ◽  
Volcanic Field ◽  
Structural Features ◽  
Heavy Fraction ◽  
Small Admixture ◽  
Volcanic Fields ◽  
Depositional Evolution

Abstract Within the framework of reinterpretation of the depositional evolution of the Komjatice depression, presence of cummingtonite in weakly lithified sediment has been detected. The sediment is formed by volcanic lithoclasts and phenocrysts with a small admixture of non-volcanic grains. The different mineral composition and various degrees of alteration of volcanic lithoclasts, together with structural features point to epiclastic origin. Therefore, the studied samples can be described as volcanic paraconglomerate and sandstone. The cummingtonite is found in rusty coloured volcanic lithoclasts and in the heavy fraction. Cummingtonite-bearing volcanic rocks have not been described so far from the Slovak Neogene volcanic fields. Therefore its presence in the studied samples represents the first indication of such volcanic rock in Slovakia. The aim of the article is to invoke interest for finding these volcanic rocks in situ.

scholarly journals Studying the effect the physicochemical properties of fine size raw coal organic and mineral composition have on beneficiation efficiency

2021 ◽  
Vol 6 ◽  
pp. 65-75
Author(s):  
Ekaterina S. Kamoza ◽  
Keyword(s):  
Mineral Composition ◽  
Structural Features ◽  
Raw Material ◽  
Petrographic Analysis ◽  
Material Base ◽  
Technical Parameters ◽  
Fine Coal ◽  
Thermal Coal ◽  
Three Samples

Introduction. This work presents the results of the research on the effect the petrographic characteristics, elemental and mineral composition have on the Kedrovsko-Krohalevskoe fine coal beneficiation efficiency. The data has been analyzed of raw coal physochemical properties at the stage of mining and dressing mill raw material base formation. Research objective is to study thermal coal by physicochemical methods of analysis to identify the main parameters affecting the quality of beneficiation products. Based on the data obtained, the research aims to develop the method of assessing the indicators affecting the beneficiation process and further forecasting during the development of new areas and coal seams. Methods of research. The structural features of raw KCN (coking low-caking low-metamorphosed) coal were determined by comparative analysis of three samples according to the following parameters: laboratory flotation results, general technical parameters, maceral composition, organic matter elemental composition, and ash mineral composition. Results. It has been established that coals of a similar nature of origin and stage of metamorphism, can have different indicators in vaarious parameters: particle size, number and morphology of microcomponents according to quantitative petrographic analysis, as well as the presence of hydrophilic functional groups on the surface of coals. Conclusions. The results of the studies made it possible to identify a number of dependencies that can be used in a preliminary assessment of the quality of raw coal sent to a coal processing enterprise.

Electron microscopy and diffraction studies of polyimides

1983 ◽  
Vol 41 ◽  
pp. 28-29
Author(s):  
O.C. de Hodgins ◽  
K. R. Lawless ◽  
R. Anderson
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Structural Features ◽  
Inert Atmosphere ◽  
Polyimide Films ◽  
Resolution Electron ◽  
The Matrix ◽  
High Resolution Electron Microscope ◽  
Diffraction Patterns ◽  
Polymeric Samples

Commercial polyimide films have shown to be homogeneous on a scale of 5 to 200 nm. The observation of Skybond (SKB) 705 and PI5878 was carried out by using a Philips 400, 120 KeV STEM. The objective was to elucidate the structural features of the polymeric samples. The specimens were spun and cured at stepped temperatures in an inert atmosphere and cooled slowly for eight hours. TEM micrographs showed heterogeneities (or nodular structures) generally on a scale of 100 nm for PI5878 and approximately 40 nm for SKB 705, present in large volume fractions of both specimens. See Figures 1 and 2. It is possible that the nodulus observed may be associated with surface effects and the structure of the polymers be regarded as random amorphous arrays. Diffraction patterns of the matrix and the nodular areas showed different amorphous ring patterns in both materials. The specimens were viewed in both bright and dark fields using a high resolution electron microscope which provided magnifications of 100,000X or more on the photographic plates if desired.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

Study of the Molecular Architecture of Keratin Filaments by Electron Microscopy

1982 ◽  
Vol 40 ◽  
pp. 118-119
Author(s):  
U. Aebi ◽  
P. Rew ◽  
T.-T. Sun
Keyword(s):  
Electron Microscopy ◽  
Structural Organization ◽  
Cell Types ◽  
Structural Features ◽  
Molecular Architecture ◽  
The Past ◽  
Keratin Filaments ◽  
Different Types ◽  
10 Nm Filaments ◽  
Different Cell Types

Various types of intermediate-sized (10-nm) filaments have been found and described in many different cell types during the past few years. Despite the differences in the chemical composition among the different types of filaments, they all yield common structural features: they are usually up to several microns long and have a diameter of 7 to 10 nm; there is evidence that they are made of several 2 to 3.5 nm wide protofilaments which are helically wound around each other; the secondary structure of the polypeptides constituting the filaments is rich in ∞-helix. However a detailed description of their structural organization is lacking to date.

Sign in / Sign up

Export Citation Format

Share Document