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Number of results: 7
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Abstract

The Bogdanka coal mine, the only currently operating mine in the Lublin Coal Basin (LCB),

extracts coal from the Upper Carboniferous formations of the LCB. The average sulfur content in

the No. 385/2 seam is 0.98%, while in the case of the No. 391 seam it is slightly higher and amounts

to 1.15%. The iron sulfides (pyrite and marcasite) in bituminous coal seams form macroscopically

visible massive, vein, and dispersed forms. A microscopic examination has confirmed their complex

structure. Massive forms contain euhedral crystals and framboids. The sulfide aggregations are often

associated with a halo of dispersed veins and framboids. Pyrite and marcasite often fill the fusinite

cells. Framboids are highly variable when it comes to their size and the degree of compaction within

the carbonaceous matter. Their large aggregations form polyframboids. The cracks are often filled

with crystalline accumulations of iron sulfides (octaedric crystals). The Wavelenth Dispersive Spectrometry

(WDS) microanalysis allowed the chemical composition of sulfides in coal samples from the

examined depoists to be analyzed. It has been shown that they are dominated by iron sulfides FeS2 –

pyrite and marcasite. The examined sulfides contain small admixtures of Pb, Hg, Zn, Cu, Ag, Sb, Co,

Ni, As, and Cd. When it comes to the examined admixtures, the highest concentration of up to 0.24%,

is observed for As. In addition, small amounts of galena, siderite, and barite have also been found in

the examined coal samples. The amounts of the critical elements in the examined samples do not allow

for their economically justified exploitation. Higher concentrations of these elements can be found in

the ashes resulting from the combustion process.

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Authors and Affiliations

Barbara Bielowicz
Jacek Misiak
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Abstract

Looking for alternative sources of energy to generate electricity has been a hot topic for society for a very long time. The need to replace current energy resources such as fuel, oil, and gas is increasing, and the replacement comes from energy obtained from the wind, sun, and sea waves. In many cases, valuable raw materials can be obtained in addition to energy production, while having a significant environmental effect simultaneously.
The shortage of energy and raw material resources in many countries stimulates the growth of interest in all potential sources of energy – solar, wind, wave, tidal – has lead to accelerating the demand for oil and gas, shale gas, as well as the expansion of the areas for the cultivation of technical crops for biofuels. Classical energy resources like oil, gas and coal are serious polluters of the natural environment. Especially harmful is the release of carbon dioxide and sulfur oxides during the exploitation of these resources.
A significant energy raw material potential of non-traditional resources lies in the waters and bottom of the Black Sea, which is a natural geobiotechnological reactor, capable of producing a variety of energy raw resources.
This paper discusses the use of hydrogen sulfide available in the Black Sea waters to produce energy and useful industrial products and proposes the respective. The technology also has an ecological effect in terms of the purification of the hydrogen sulfide pool. The paper also discusses some technologies for the separation of hydrogen sulfide to hydrogen and sulfur. An estimation of the heat value of hydrogen sulfide in the water of the Black Sea is also presented.
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Authors and Affiliations

Iskra Simova
1
Rositsa Velichkova
1
Milka Uzunova
2
Radostina Angelova
1
Peter Stankov
1
Koycho Atanasov
3

  1. Hydroaerodynamic and Hydraulic Machines, Technical University of Sofia, Bulgaria
  2. ECAM-EPMI, France
  3. Technical University of Sofia, Bulgaria
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Abstract

There is a sulfide mineralization vein type in the Cindakko area, Maros Regency, South Sulawesi. The results of mineralogical studies on the Cindakko prospects for sulfide ore mineralization are explained in this paper. Petrographic, mineragraphic, and XRD methods analyzed the mineralization and alteration samples from the research area. The results showed that the host rock mineralization is basalt, a member of the Baturappe-Cindakko Volcano from the Late Miocene age. The identified hydrothermal alteration mineral associations include quartz, chlorite, epidote, biotite, actinolite, and pyrite, generally formed in propyllitic alteration zones mainly characterized by chlorite. The analysis provides the occurrence of mineralization types: crustiform-banding quartz veins, vuggy quartz, and disseminated, contain hypogenic pyrite, chalcopyrite, sphalerite, bornite, and tennantite ores, and supergene ore minerals in the form of covellite. Ore textures recognized under a microscope are intergrowth, replacement, open-space filling, and exsolution. Based on the interpretation of temperature stability of hydrothermal alteration minerals, it is concluded that it was formed at approximately 200 to 320°C with the hydrothermal fluid pH almost neutral. The fundamental characteristics of hydrothermal alteration, ore mineral assemblage and texture, mineralization type, temperature range form, and hydrothermal fluid pH indicate that the mineralization in the Cindakko Prospect is an epithermal type.
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Authors and Affiliations

Ibnu Munzir
1
ORCID: ORCID
Arif Arif
2
Musri Mawaleda
3
Irzal Nur
4

  1. Institute of Geological Science, Jagiellonian University, Kraków, Poland
  2. Department of Earth Resources Engineering, Kyushu University; Japan
  3. Geology Engineering Department, Hasanuddin University, Gowa 92171, South Sulawesi; Indonesia
  4. Mining Engineering Department, Hasanuddin University, Gowa 92171, South Sulawesi; Indonesia
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Abstract

Hydrogen sulfide (H2S) regulates many critical processes of plants. The effect of sodium hydrogen sulfide as H2S agent was investigated in basil plants under cadmium stress. A completely randomized design with three different concentrations (0, 50 and 100 μM) of CdCl2 and two levels of NaHS (0 and 100 μM) was used in this study. Cadmium exposure reduced growth parameters and relative water content. Cd also caused a significant increase in ion leakage and higher oxidative stress in terms of lipid peroxidation and H2O2 production. Although exogenous NaHS used in non-stressed control plants negatively affected growth and physiological parameters, it improved the root/shoot length ratio and fresh weight in basil plants under Cd 50 μM exposure. Moreover, NaHS alleviated deleterious effects of cadmium on ion leakage, relative water content and photosynthetic pigments of leaves. The activity of antioxidant enzymes like catalase, peroxidase and ascorbate peroxidase were also enhanced by NaHS in plants under moderate cadmium stress. Our results show that NaHS 50 μM ameliorates growth retardation induced by cadmium 50 μM stress in basil plants, probably through regulating physiological parameters such as photosynthetic pigments content, relative water content and the activity of antioxidant enzymes.

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Authors and Affiliations

Hakimeh Oloumi
Mansooreh Khodashenas
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Abstract

This paper presents an analysis of non-metallic inclusions occurring in high-silicon steels containing about 3% Si of terms of their type, volume fraction and morphology. The inclusions were divided into 3 main groups: oxides, sulfides, nitrides which together can also form complex. The work was based on numerous metallographic observations in two sections (longitudinal and transverse to the rolling direction). The study was performed on three casts differing in chemical composition. The analyzed casts were characterized by a different content of non-metallic inclusions, which can be associated with slight differences in chemical composition. The analyzed results showed that the most common inclusions were oxides and nitrides. Sulfides occurred sporadically.
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Authors and Affiliations

K. Ścibisz
1
ORCID: ORCID
J. Krawczyk
2
ORCID: ORCID

  1. ArcelorMittal Poland S.A. Unit in Krakow, Tadeusza Sendzimira 1 Str., 31-752 Krakow, Poland; AGH University of Krakow, Faculty of Metals Engineering and Computer Science, AGH Do ctoral School, al. Mickiewicza 30, 30-059 Krakow, Poland
  2. AGH University of Krakow, Faculty of Metals Engineering and Computer Science, Al. Mickiewicza 30, 30-059 Krakow, Poland
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Abstract

Composting of municipal solid waste with a 1 % addition of pulverized metallic iron, iron oxide(III) and iron sulfide(II) has been carried out. The amounts of iron in the bioavailable forms have been assayed in the composts obtained by means of speciation analysis, and the influence of composting on iron mobility has been evaluated. It has been found that pulverized metallic iron introduced into the waste occurs in the compost in the fractions easily accessible to plants, mainly the carbonate fraction. In the waste contaminated with Fe203 iron remains in the residual fraction, and composting does not practically increase its mobility. Over half of the iron from FeS remains in the waste in the residual fraction however, after composting there was an increased iron concentration in the bioavailable carbonate fraction.
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Authors and Affiliations

Jerzy Ciba
Maria Zolotajkin
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Abstract

Measurements were made of sediment characteristics, benthic microbial activity and optimum temperature for sulfate reduction at Signy Island, South Orkney Islands, Antarctica . There was little evidence to support any seasonal variation in oxygen penetration of surface sediments. Oxygen penetrated to only 1.5 to 3 mm throughout the year, despite bioturbation from a dense amphipod population. The distribution of acid volatile sulfides increased with depth below 1 cm and above this, surface sediments were lighter in colour and contained fewer sulfides. The rates of sulfate reduction increased during winter under sea-ice cover, and remained high after ice break up. Seasonal water temperature was relatively constant between –1.8 and 0.5°C. Optimum temperature for anaerobic sediment respiration was investigated using different substrates and was found to be in the range 17–27°C, suggesting that sulfate reducing bacteria are psychrotolerant as they were inhibited by low temperatures.

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Authors and Affiliations

Tony R. Walker

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