ferrous metal
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2021 ◽  
Vol 37 (4) ◽  
Author(s):  
Jolanta Surgiewicz

Arsenic is a chemical element classified as metalloids (semi-metals). Some arsenic compounds have been classified (according to CLP) as carcinogens, causing cancers of skin, respiratory system, liver and leukemia. In the industry, workers are exposed to arsenic and its compounds in its extraction, in metallurgy of non-ferrous metal ores, in metal refining processes, in the production of alloys, semiconductors, pigments and insecticides. In Poland, binding value of the hygienic standard (NDS) at workplace air, for the inhalable fraction of arsenic aerosol and its inorganic compounds, converted into As is 0.01 mg/m3 . A determination method has been developed that enables the determination of this substance in the air of 0.1 − 2 values of the hygiene standard, in accordance with the requirements of Standard PN-EN 482. Arsenic is determined with the atomic absorption spectrometry with electrothermal atomization (ET-AAS), in the concentration range of 5.00 − 100.0 μg/l which allows the determination of arsenic and its compounds in workplace air in the range of 0.0010 − 0.021 mg/m3 (for 480-L air sample). The presented procedure enables the determination of this substance with the use of individual dosimetry. This article discusses the problems of occupational safety and health, which are covered by health sciences and environmental engineering.


Author(s):  
A.D. Degtyareva

The article presents data on the morphological and typological characteristics of the trade tools of the Pet-rovka Culture of the South Trans-Urals and middle Tobol River region, originating from the sites of Chelyabinsk, Kurgan, and Tyumen Regions (77 specimens in total; 126 specimens in total including knives). According to the radiocarbon dating, the chronological period of the Petrovka sites in the Southern Trans-Urals spans the 19th through 18th centuries B.C. The distribution of tools into types was based on the techniques of typological division of the artifacts, taking into account their shape, presence of certain qualitative features, as well as consideration of the geographical and cultural areal of similar articles. The produce of the Southern Trans-Urals center is repre-sented by a diverse set of metal tools and by functioning of large settlements with metallurgical specialization — Kulevchi 3, Ustye 1, and Shibaevo 1. In the typology of the tool complex of the Petrovka Culture of the Southern Trans-Urals and the Middle Pre-Tobol region, common Eurasian types dominate, being genetically associated with the centers of the Middle Bronze Age of the Circumpontian Metallurgical Province — the Late Yamnaya-Poltavkino, Catacomb Culture, and metal-producing centers of the Corded Ware Culture — Volsk-Lbische and Balanovo. A pronounced variety of the morphotypes of the tools, especially knives, is characteristic of the initial stage of ethnogenesis of the cultures of the forest-steppe and steppe zone of Eurasia during the transitional pe-riod from the MBA to the LBA. Common Eurasian types of tools are characteristic of the cultures of the 1st phase of the Eurasian (West Asian) metallurgical province of the forest-steppe and steppe belt from the Don region to the Irtysh region: Abashevo; Sintashta; Early Srubnaya (Pokrovka); Petrovka (Early Alakul). Specific groups of tools inherent in the tribes of the Petrovka Culture were revealed: axes with a massive head; medium-curved sick-les with a prominent handle; socketed spearheads without eyelets and raised ribs along the edge of the socket; forged arrowheads with a through socket; knives with a straight prominent handle — double-edged and single-edged; knives with a forged open socket. In the appearance of some types of tools among the Petrovka population of the Trans-Urals, such as forged socketed tools — chisels, knives, arrows, double-edged knives with a prominent handle, and sickles with a small curvature, the influence of the Abashevo stereotypes of production is discernible. In the meantime, sufficient data have been obtained on the direct imports or on the conjugation of types of the metal tools and weapons of the Sintashta, Petrovka, and Seima-Turbino Cultures in closed complexes.


2021 ◽  
pp. 902-915
Author(s):  
Alexey Vladimirovich Kuznetsov

The article shows that although the threat of rapid depletion of mineral resources in the world is largely exaggerated, imbalances in their distribution and consumption are gradually increasing. On the one hand, globalization intensifies the competition of countries for resources, as the global development of recent decades shows. On the other hand, globalization mitigates imbalances through foreign trade and direct investment. The article examines the role of Russian investor companies in these processes. The research is based on corporate materials, official statistics and the most authoritative sources of industry information. The contribution of Russian oil and gas TNCs, companies specializing in the construction and operation of nuclear power plants and hydroelectric power plants, as well as leading investors in the field of non-ferrous metal industry was studied. A distinctive feature of Russian TNCs is the limited geography of their foreign business, especially in the countries of the global South. Usually we can see the preference of a narrow circle of countries which had long history of good political relations with Russia. At the same time, reliance on purely economic considerations is less pronounced than that of leading Western competitors. As a result, external shocks (whether political cataclysms in individual countries in the case of the oil and gas sector or sharp fluctuations in the international conjuncture in the case of non-ferrous metal industry) can greatly affect the scale of foreign activity of Russian TNCs. For the time being, it is more likely that we can still talk about the initial stages of internationalization of Russian business, which has little effect on the nature of global development with its investment activity. The article also shows that since in the future the scarcity of land and water resources will increase in the global economy, additional opportunities will open up for Russian companies to strengthen our country’s international positions. However, so far the activity of Russian TNCs is not observed there because it is limited mainly by the increase in grain exports to developing countries.


2021 ◽  
Vol 940 (1) ◽  
pp. 012054
Author(s):  
H Pratikno ◽  
H S Titah ◽  
D M Aisyah

Abstract Steel is an alloy of ferrous metal with a maximum carbon content of 2%. This material is widely used for jetty building structures at rivers, estuary, and coastal areas. Corrosion of steel can occur due to several factors, such as the steel material itself and the surrounding environmental factors. One of the corrosion is biocorrosion that occurs due to the presence of biofouling. This study aims to determine the effect of adding extraction of mangrove (Avicennia marina) as an antifouling compound mixed in epoxy paint through adhesion strength parameter. Then the alloy was applied as a coating on the ASTM A36 steel specimen. The variation of coating composition were 100% of epoxy paint, 90%:10% (epoxy paint and extraction of Avicennia marina), 80% : 20% and 70% : 30%. The results showed that the adhesion strength occurred in 100% of epoxy paint (10.15 ± 0.64 Mpa). The adhesion strength was 8.86 ± 0.21 Mpa, 8.50 ± 0.03 Mpa, and 8.19 ± 0.07 Mpa at ratio of composition coating 90%: 10%, 80%: 20%, and 70%: 30%, respectively. In conclusion, the more mangrove extraction was added, the smaller the adhesion strength.


KALPATARU ◽  
2021 ◽  
Vol 30 (2) ◽  
pp. 141-152
Author(s):  
Harry Octavianus Sofian

Abstract. Technological knowledge of the use of metals is inseparable from human knowledge in the processing pyrotechnics of fire as a power in high temperature processes for producing objects. The fire is used for smelting and casting in melting furnaces. Metal smelting furnace is a heat production device, which is used to purify the metal, in this case iron. This paper aims to determine the development of ferrous metal smelting furnace technology in Indonesia with the library research method from the results of previous studies. Based on the results of the analysis, there are four technologies for smelting iron, namely pit kiln, bloomery furnace, blast furnace, and induction furnace. Of the four technologies, three are in use in Indonesia, namely bloomery furnace, blast furnace, and induction furnace.


2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Kaihe Shi ◽  
Danning Du ◽  
Xiaoxuan Zhang

Supply-side structural reforms and environmental protection policies have a great impact on the ferrous metal smelting and rolling processing industry. This paper uses a grey model that introduces a fractional-order cumulative generating operator to study the development of ferrous metal smelting and rolling processing enterprises under the influence of supply-side structural reform in order to derive the future development trend of the industry. The forecast results show that from 2018 to 2022, the number of enterprises and substitute enterprises, inventory, finished products, and assets and liabilities decreases; the scale of income of metal smelting and rolling processing industry increases. The results can serve as a reference for policy makers and industry investors.


Author(s):  
Yanxin Hu ◽  
Chuan Wang ◽  
Zhengcheng Song ◽  
Min Chen ◽  
Li Ding ◽  
...  

Non-ferrous metal smelting is a significant source of anthropogenic heavy metal emission and has led to severe environmental pollution that ultimately threatens the health of local residents. In this study, we determined concentrations of copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb), as well as Pb isotopic compositions in rice, vegetables and human hair in areas surrounding the Zhuzhou Pb/Zn smelter in Hunan, China and we assessed the health risks associated with rice and vegetable consumption for local residents. Results showed that rice and vegetable samples were significantly contaminated by Cd and Pb. Age and source of rice were important factors for the enrichment of heavy metal concentrations in human hair. The ratios of Pb isotopes in human hair (1.164–1.170 for 206Pb/207Pb and 2.102–2.110 for208Pb/206Pb) were comparable to those in rice (1.162–1.172 for 206Pb/207Pb and 2.098–2.114 for208Pb/206Pb) and were slightly lower than those in vegetables (1.168–1.172 for 206Pb/207Pb and 2.109–2.111 for208Pb/206Pb), indicating that Pb in human hair mainly originated from food ingestion. A non-carcinogenic risk assessment showed that Cd exposure was the dominant health risk for local residents. This study suggested that crops planted surrounding the smelter were seriously contaminated with Cd and human exposure was related to dietary intake.


2021 ◽  
Author(s):  
S.V. Gladyshev ◽  
◽  
M.N. Azlan ◽  

The method of preliminary chemical activation of mineral raw materials was used in the conducted studies for the complex processing of pyritic slags. The influence of preliminary chemical activation of kaolinite clays of Alexeevsky deposit in the solution of sodium hydrogen carbonate on the separation of kaolinite and quartz fractions was studied. The temperature of 150 oC, the duration of 120 minutes, and the concentration of sodium bicarbonate solution of 120 g/dm3 should be considered the optimum mode of activation. As a result of activation, the phase composition of the kaolinite fraction changed: the percentage of kaolinite fraction decreased; new phases of muscovite and sodium aluminosilicate appeared; the amount of quartz increased.


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