Metasomatic studies in Bulgaria – an overview

This brief overview presents the study of metasomatic processes and rocks in Bulgaria. The very beginning of metasomatic studies coincides with the first steps of Bulgarian geology, with the discovery and description of minerals that are basic for altered rocks. Subsequently, the processes of spilitization and uralitization, the formation of fluorite-silicated rocks during intensive metasomatic alteration of marbles, were characterized. Around and after 1950, the increase in mapping and geological and mining activities created prerequisites for rapid development of the study of metasomatic processes, and especially of wall-rock alterations as their particular cases. Many new data filled in the pages of geological reports and the first dissertations. This was also the time of characterization of new metasomatic processes and metasomatic products for Bulgaria: potassium feldspatization and granitization, propylites and secondary quartzites, etc. Nowadays, the following metasomatic families have been established in Bulgaria: skarn, quartz-feldspar metasomatic rocks, greisen, beresite, secondary (hydrothermal) quartzite, propylite, argillisite, aceite, quartz-sericite and quartz-adularia-sericite. The products of potassium feldspatization and granitization, as well as rodingites, can also be included. The Geological Institute “Strashimir Dimitrov” (Bulgarian Academy of Sciences) is the cradle of the metasomatic doctrine in Bulgaria. Taking the best of world science, the metasomatic direction in our country has created its own image. Collaboration with prominent specialists from leading countries have helped Bulgarian metasomatists grow and show their knowledge at a number of geological forums in Bulgaria and abroad, as well as in theoretical and practical aspects taking part in exploration works in other countries. Proof of growth are the monographs issued; the large number of scientific and popular articles; the defended 17 PhD and four DSc theses; the new, found in Bulgaria, minerals, rocks, deposits and occurrences of ore and non-metallic raw materials with different applications. This overview examines in a detailed way the different directions in researches on metasomatic processes in Bulgaria: geochemical, mineralogical-petrological, structural-tectonic, theoretical and experimental modelling. The most important scientific and applied contributions are noted, and the problems in the study of metasomatic processes are briefly discussed. Research on metasomatic rocks (especially wall-rock alterations) and results are widely used in the discovery of a number of ore and raw material deposits, as well as in the proper direction of geological exploration and mining in promising areas.

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A Methodology Based on FT-IR Data Combined with Random Forest Model to Generate Spectralprints for the Characterization of High-Quality Vinegars

Foods ◽

10.3390/foods10061411 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1411

Author(s):

José Luis P. Calle ◽

Marta Ferreiro-González ◽

Ana Ruiz-Rodríguez ◽

Gerardo F. Barbero ◽

José Á. Álvarez ◽

...

Keyword(s):

Random Forest ◽

Raw Materials ◽

Principal Component ◽

Hierarchical Cluster ◽

Raw Material ◽

Support Vector ◽

Protected Designation Of Origin ◽

Ft Ir

Sherry wine vinegar is a Spanish gourmet product under Protected Designation of Origin (PDO). Before a vinegar can be labeled as Sherry vinegar, the product must meet certain requirements as established by its PDO, which, in this case, means that it has been produced following the traditional solera and criadera ageing system. The quality of the vinegar is determined by many factors such as the raw material, the acetification process or the aging system. For this reason, mainly producers, but also consumers, would benefit from the employment of effective analytical tools that allow precisely determining the origin and quality of vinegar. In the present study, a total of 48 Sherry vinegar samples manufactured from three different starting wines (Palomino Fino, Moscatel, and Pedro Ximénez wine) were analyzed by Fourier-transform infrared (FT-IR) spectroscopy. The spectroscopic data were combined with unsupervised exploratory techniques such as hierarchical cluster analysis (HCA) and principal component analysis (PCA), as well as other nonparametric supervised techniques, namely, support vector machine (SVM) and random forest (RF), for the characterization of the samples. The HCA and PCA results present a clear grouping trend of the vinegar samples according to their raw materials. SVM in combination with leave-one-out cross-validation (LOOCV) successfully classified 100% of the samples, according to the type of wine used for their production. The RF method allowed selecting the most important variables to develop the characteristic fingerprint (“spectralprint”) of the vinegar samples according to their starting wine. Furthermore, the RF model reached 100% accuracy for both LOOCV and out-of-bag (OOB) sets.

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A Tale of Two Tiles: Characterization of Floor Tiles from the Nineteenth-Century Akko Tower Shipwreck (Israel)

Coatings ◽

10.3390/coatings10111091 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1091

Author(s):

Alexandra Inberg ◽

Dana Ashkenazi ◽

Yishai Feldman ◽

Omri Dvir ◽

Deborah Cvikel

Keyword(s):

Secondary Ion Mass Spectrometry ◽

Raw Materials ◽

Type A ◽

Raw Material ◽

Brown Pigment ◽

Blue Color ◽

Type B ◽

Yellow Color ◽

Floor Tiles

Fragments of decorated floor tiles were retrieved from the Akko Tower shipwreck, Israel. Most tiles were made of bright brown fired clay with a white glaze decorated with colored stenciled motifs (Type A); and others consisted of a red-brown fired clay body, coated with a brown pigment covered with transparent brown glaze (Type B). This study aimed to characterize the two tile types; to reveal information concerning the manufacturing process; and to determine the origin of their raw material. A multidisciplinary approach was used, including light microscopy, SEM-EDS, electron probe microanalysis with wavelength-dispersive X-ray spectroscopy (EPMA-WDS), XRD, Raman spectroscopy, and time-of-flight secondary ion mass spectrometry (TOF-SIMS) analyses. The characterization of both tile types demonstrated the use of different raw materials. The Type A tiles were covered with tin-opacified majolica glaze and colored with various mixtures of pigments. The blue color was due to pigment rich in cobalt; the yellow color was due to Naples yellow and lead-tin yellow I minerals; and the green, orange, and brown colors were all prepared by mixing the Naples yellow pigment with different minerals. These majolica glaze tiles were probably manufactured in Sicily. The brown coating of the Type B tiles was due to pigment rich in lead and iron minerals. These tiles were produced with different manufacturing processes, and apparently made in France.

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QUALIDADE DO CALDO PARA PRODUÇÃO DE ETANOL EM CULTIVARES DE SORGO SACARINO SOB ADUBAÇÃO NITROGENADA

Revista Brasileira de Milho e Sorgo ◽

10.18512/1980-6477/rbms.v16n3p388-400 ◽

2017 ◽

Vol 16 (3) ◽

pp. 388

Author(s):

CRISTÓBAL SOTO SOLANO ◽

NIRALDO JOSÉ PONCIANO ◽

ROGÉRIO FIGUEIREDO DAHER ◽

RAFAEL AUGUSTO DA COSTA ◽

PAULO MARCELO DE SOUZA ◽

...

Keyword(s):

Ethanol Production ◽

Nitrogen Fertilization ◽

Ethanol Yield ◽

Raw Materials ◽

Raw Material ◽

Maximum Value ◽

Total Reducing Sugars ◽

Nitrogen Rates

RESUMO - O sorgo sacarino tem potencial de uso como fonte de matéria-prima para a produção de bioetanol. Objetivou-se, com este estudo, analisar o efeito da adubação nitrogenada de cobertura na qualidade do caldo para produção de etanol de quatro cultivares de sorgo sacarino. O experimento foi conduzido em Campos dos Goytacazes- RJ, de janeiro a maio de 2014. Foram estudadas quatro cultivares de sorgo sacarino: BRS 506, BRS 508, BRS 509 e BRS 511 e cinco de doses de nitrogênio (0, 80, 160, 240 e 320 Kg ha-1), aplicadas aos 25 e 45 dias após semeadura. Os resultados mostraram que valor Brix, açúcares redutores totais, açúcares totais recuperáveis, volume do caldo e rendimento de etanol foram afetados pela adubação nitrogenada. Para todas as características, o valor máximo foi obtido pela dose de 240 kg de N ha-1. Entre as cultivares, a BRS 506 mostrou-se superior em produção de caldo e rendimento de etanol. Enquanto a BRS 511 destacou-se nos atributos ART e ATR, e a cultivar BRS 508 sobressaiu-se no valor Brix. A cultivar BRS 506 apresentou melhor resultado combinado, com maior volume de caldo e rendimento de etanol com as doses de 204 e 212 kg N ha-1, respectivamente. Palavras-chave: biocombustíveis, rendimento de álcool carburante, atributos industriais, caracterização da matéria prima, genótipos. QUALITY OF BROTH FOR ETHANOL PRODUCTION IN CULTIVARS OF SACARINE SORGHUM UNDER NITROGEN FERTILIZATION ABSTRACT - Sweet sorghum has potential as a source of raw material for the production of bioethanol. The objective of this study was to analyze the effect of nitrogen topdressing on the quality of the juice for ethanol production from four cultivars of sorghum. The experiment was conducted in Campos, State of Rio de Janeiro, Brazil, from January to May 2014. Four cultivars of sorghum: BRS 506, BRS 508, BRS 509 and BRS 511 were studied, and five nitrogen rates (0, 80, 160, 240 and 320 kg ha-1), applied to 25 and 45 days after sowing. The results showed that the value Brix, total reducing sugars, total recoverable sugars, broth volume and ethanol yield were affected by nitrogen fertilization. For all features, the maximum value was obtained for the dose of 240 kg N ha-1. Among cultivars, BRS 506 was superior in production of broth and ethanol yield. BRS 511 stood out in the attributes ART and ATR, and BRS 508, in value Brix. BRS 506 had better combined result of higher volume of juice and ethanol yield with doses of 204 and 212 kg N ha-1, respectively Keywords: biofuels, fuel ethanol output, industrial attributes, characterization of raw materials, genotypes.

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Investigations of quartz raw materials from the locality of Rekovac muncipality

Hemijska industrija ◽

10.2298/hemind190328023m ◽

2019 ◽

Vol 73 (4) ◽

pp. 265-274

Author(s):

Slavica Mihajlovic ◽

Zivko Sekulic ◽

Jovica Stojanovic ◽

Vladan Kasic ◽

Iroslav Sokic ◽

...

Keyword(s):

Chemical Composition ◽

Physical Properties ◽

Quartz Sand ◽

Raw Materials ◽

Construction Materials ◽

Size Fraction ◽

Point Of View ◽

Raw Material ◽

Potential Applications

Quality of raw materials, including quartz sand and quartzite, varies from one deposit to another. Furthermore, the material quality determines in which industrial branches it can be used after certain preparation processes. Potential applications of quartz raw materials are: in the construction and refractory industry, ceramics and glass industry, then in metallurgy, foundry and also in production of water treatment filters. Geological investigations of the central Serbia region, in the Rekovac municipality, resulted in identification of occurrence of quartz sand ("Ursula") and quartzite ("Velika Krusevica"). Preliminary laboratory tests and characterization of the quartz sand size fraction -0.63+0.1 mm confirmed the possibility of applying this size fraction in the construction materials industry, while the quartzite can be used in refractory, glass and metallurgy industries. After determining the geological reserve of quartz sand "Ursula" and quartzite "Velika Krusevica", detailed investigations are required. Quality conditions from the aspect of chemical composition and physical properties of quartz sand and quartzite are mostly clearly defined by a special standard for this purpose. On the other hand, there are also application areas where standards does not exist, but users define their quality conditions. This example is with the application of quartz sand in the production of water glass. Chemical composition as well is not always the determining factor for the application of quartz raw material. For example, for quartz sand used for sandblasting, grain form is essential. From the economic analysis point of view, the prices of quartz raw materials vary depending on their chemical and physical properties. After all, what needs to be pointed out is the fact that these raw materials are very widespread in nature and that their exploitation is quite simple. After the raw material is excavated, it is stored and further sieved, washed, dried and processed according to customer requirements. All of these processes are cheaper than preparing, for example, limestone, and significaly cheaper than preparation of metal ores.

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Synthesis and characterization of innovative insulation materials

MATEC Web of Conferences ◽

10.1051/matecconf/201814901078 ◽

2018 ◽

Vol 149 ◽

pp. 01078

Author(s):

Aggeliki Skaropoulou ◽

Afroditi Ntziouni ◽

Dimitris Kioupis ◽

Sotiris Tsivilis ◽

Glikeria Kakali

Keyword(s):

Raw Materials ◽

Raw Material ◽

Synthesis And Characterization ◽

Insulation Material ◽

Foaming Agent ◽

Insulation Materials ◽

Major Disadvantage ◽

Reinforcing Agent ◽

By Products

Insulation elements are distinguished in inorganic fibrous and organic foamed materials. Foamed insulation materials are of great acceptance and use, but their major disadvantage is their flammability. In case of fire, they tend to transmit the flame producing toxic gases. In this paper, the synthesis and characterization of innovative inorganic insulation materials with properties competitive to commercial is presented. Their synthesis involves the mixing of inorganic raw material and water with reinforcing agent or/and foaming agent leading to the formation of a gel. Depending on raw materials nature, the insulation material is produced by freeze drying or ambient drying techniques of the gel. The raw material used are chemically benign and abundantly available materials, or industrial by-products and the final products are non-toxic and, in some cases, non-flammable. Their density and thermal conductivity was measured and found 0.02-0.06 g/cm3 and 0.03-0.04 W/mK, respectively.

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Production of Foundry Filters Using Al2O3 from the Al-Anodizing Process

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.62.119 ◽

2010 ◽

Vol 62 ◽

pp. 119-124 ◽

Cited By ~ 1

Author(s):

Graziela G. de Moraes ◽

Bianca G. Oliveira ◽

Cristina Siligardi ◽

Murilo Daniel de Mello Innocentini ◽

Amir A.M. Oliveira Jr. ◽

...

Keyword(s):

Particle Size ◽

Raw Materials ◽

Raw Material ◽

Industrial Processes ◽

High Alumina ◽

Secondary Products ◽

Ceramic Filters ◽

Application Potential ◽

Aluminum Anodizing

The manufacturing and materials transformation industries generate residues, which do not always have an adequate ecological destination. In many cases, however, these secondary products can be directly re-used as raw materials in other industrial processes. In this context, this article presents the characterization of the sludge generated in the aluminum anodizing process and emphasizes the application potential of this residue as a raw material for the production of industrial ceramic filters. Results show that the high alumina contents (89-96 wt%) and composition constancy, as well as the low particle size (~1 m) after calcination and milling, render this residue a suitable raw material to produce alumina filters with optimized properties for casting engineering metal components with better performance.

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Chert from the Vegamián Formation: A new raw-material supply source in the Cantabrian Mountains (NW Spain) during prehistory

Journal of Lithic Studies ◽

10.2218/jls.v3i2.1449 ◽

2016 ◽

Vol 3 (2) ◽

Cited By ~ 1

Author(s):

Diego Herrero-Alonso ◽

Antonio Tarriño-Vinagre ◽

Ana Neira-Campos ◽

Natividad Fuertes-Prieto

Keyword(s):

Raw Materials ◽

Raw Material ◽

Cantabrian Mountains ◽

Nw Spain ◽

Supply Source ◽

Geochemical Characterization ◽

Material Supply ◽

Different Types

This work provides the keys to the mineralogical and geochemical characterization of black chert from the Vegamián Fm. This formation crops out throughout the whole of the Cantabrian Zone (of Palaeozoic age), one of the geological zones of the Cantabrian Mountains (NW Spain). The geographical distribution of this formation is very wide, surfacing in the provinces of León, Asturias, Palencia and Cantabria.This variety of chert had been included within the group generically known as ‘black chert’, a macrogroup including different types of chert that appear in different Palaeozoic formations in the area and which share a characteristic black colour at the macroscopic level. The characterisation presented here has enabled us to distinguish it from other varieties. In this study, Vegamián chert has been divided into two different groups depending on their textural, mineralogical, geochemical and thermal propierties. Type 1, the most suitable for knapping, is characterized by high content in silica (>97%), laminated matrix and, occasionally, ghost of radiolarians. In addition, the characteristics specific to this chert make it suitable for lithic knapping processes. To confirm its use by prehistoric populations, this chert will be compared to that found in two Mesolithic sites, the caves of La Uña and El Espertín (León, south versant of the Cantabrian Mountains), the raw materials from which are currently under study.

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Development and proximate and microbiological characterization of Nile Tilapia (Oreochromis niloticus) protein hydrolyzed.

Revista Brasileira de Pesquisa em Alimentos ◽

10.14685/rebrapa.v4i1.97 ◽

2014 ◽

Vol 4 (1) ◽

pp. 27

Author(s):

Juliana Cristina Veit ◽

Aldi Feiden ◽

Marcia Luzia Ferrarezi Maluf ◽

Wilson Rogerio Boscolo

Keyword(s):

Nile Tilapia ◽

Raw Materials ◽

Nutrient Content ◽

Biological Properties ◽

Raw Material ◽

Degree Of Hydrolysis ◽

High Productivity ◽

Nile Tilapia Oreochromis Niloticus ◽

Health Quality

The proteic hydrolysis is a technology developed with the aim of adding value, functionality and increase the use of undervalued raw materials. Through this process is possible to modify the chemical, physical and biological properties of proteins without changing their nutrient content. This study aimed to develop proteic hydrolyzed of Nile tilapia “V” cuts and to characterize them according to their degree of hydrolysis, chemical composition and microbiology. The results of analyses showed that the developed hydrolyzed had high productivity and appropriate degree of hydrolysis (14.8 % to H1 and 13.2 % to H2) that allow to use them both in the treatment of diseases as a flavoring in foods. In addition to presenting good composition, similar to the initial raw material, with 81.4 and 81.0 % for moisture, 13.6 and 14.6 % for protein, 3.5 and 2.8 % for lipids and 2.7 and 2.0 % for ash, respectively for H1 and H2. With relation to microbiological results, the hydrolyzed showed great health quality, well below the limits allowed by law. Therefore, the enzymatic hydrolysis proved to be an efficient process to obtain hydrolyzed proteins from a high biological value and low value raw material. DOI: <a href="http://dx.doi.org/10.14685/rebrapa.v4i1.97">http://dx.doi.org/10.14685/rebrapa.v4i1.97</a>

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Characterization of the Obsidian Used in the Chipped Stone Industry in Kendale Hecala

Quaternary ◽

10.3390/quat5010003 ◽

2022 ◽

Vol 5 (1) ◽

pp. 3

Author(s):

Üftade Muşkara ◽

Ayşin Konak

Keyword(s):

Multivariate Analysis ◽

Raw Materials ◽

Raw Material ◽

Chipped Stone ◽

Cultural Organization ◽

Lithic Industry ◽

Southeast Anatolia ◽

Stone Industry ◽

Technological Analysis

Kendale Hecala is located on the Ambar River in the Upper Tigris Basin, province of Diyarbakır in Southeast Anatolia. Various raw materials, including obsidian, radiolarite, chert, jasper, chalcedony, and quartzite, were used in the lithic industry. Obsidian artefacts constitute an average of 64% of the chipped stone assemblage. Technological analysis reveals that obsidian was brought to the settlement as nodules and chipped into various tools at the settlement. Understanding the operational sequence of the lithic industry, chaîne opératoire, including the distribution of raw material from source to site, is important to demonstrate the socio-cultural organization of the settlement in Southeastern Anatolia during the Ubaid period. In order to identify source varieties, the obsidian artefacts uncovered from Ubaid layers of Kendale Hecala were analyzed by macro-observations, and the characterization of archaeological samples was performed using a handheld XRF. Multivariate analysis of the data indicates the use of obsidian from different resources at the settlement, including Nemrut Dağ, Bingöl B, and Group 3d.

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Evaluation of Kalalani vermiculite for production of high strength porcelain insulators

Science of Sintering ◽

10.2298/sos1902223n ◽

2019 ◽

Vol 51 (2) ◽

pp. 223-232 ◽

Cited By ~ 1

Author(s):

Blasius Ngayakamo ◽

Eugene Park

Keyword(s):

Water Absorption ◽

Bulk Density ◽

Bending Strength ◽

Raw Materials ◽

High Strength ◽

Microstructural Characterization ◽

Dielectric Strength ◽

Raw Material ◽

Porcelain Insulators

The present work has evaluated Kalalani vermiculite as a potential raw material for the production of high strength porcelain insulators. Three porcelain compositions were prepared to contain 0, 20 and 30 wt% of Kalalani vermiculite. Porcelain samples were fabricated using a semi-drying method. The chemical, mineralogical phases and microstructural characterization of the raw materials were carried out using XRF, XRD, and SEM techniques, respectively. Water absorption, bulk density, dielectric and bending strengths were performed on porcelain samples fired up to 1300?C. However, at the sintering temperature of 1250?C, the porcelain sample with 20 wt% of Kalalani vermiculite gave the dielectric strength of 61.3 kV/mm, bending strength of 30.54 MPa, bulk density of 2.21 g/cm3 and low water absorption value of 0.21 % which is the prerequisite properties for high strength porcelain insulators. It was therefore concluded that Kalalani vermiculite has the potential to be used for the production of high strength porcelain insulators

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