Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 327
Filtrar
Más filtros

Medicinas Complementárias
Tipo del documento
Intervalo de año de publicación
1.
Environ Sci Process Impacts ; 25(9): 1491-1504, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37584085

RESUMEN

Exposures to metals from industrial emissions can pose important health risks. The Chester-Trainer-Marcus Hook area of southeastern Pennsylvania is home to multiple petrochemical plants, a refinery, and a waste incinerator, most abutting socio-economically disadvantaged residential communities. Existing information on fenceline community exposures is based on monitoring data with low temporal and spatial resolution and EPA models that incorporate industry self-reporting. During a 3 week sampling campaign in September 2021, size-resolved particulate matter (PM) metals concentrations were obtained at a fixed site in Chester and on-line mobile aerosol measurements were conducted around Chester-Trainer-Marcus Hook. Fixed-site arsenic, lead, antimony, cobalt, and manganese concentrations in total PM were higher (p < 0.001) than EPA model estimates, and arsenic, lead, and cadmium were predominantly observed in fine PM (<2.5 µm), the PM fraction which can penetrate deeply into the lungs. Hazard index analysis suggests adverse effects are not expected from exposures at the observed levels; however, additional chemical exposures, PM size fraction, and non-chemical stressors should be considered in future studies for accurate assessment of risk. Fixed-site MOUDI and nearby mobile aerosol measurements were moderately correlated (r ≥ 0.5) for aluminum, potassium and selenium. Source apportionment analyses suggested the presence of four major emissions sources (sea salt, mineral dust, general combustion, and non-exhaust vehicle emissions) in the study area. Elevated levels of combustion-related elements of health concern (e.g., arsenic, cadmium, antimony, and vanadium) were observed near the waste incinerator and other industrial facilities by mobile monitoring, as well as in residential-zoned areas in Chester. These results suggest potential co-exposures to harmful atmospheric metal/metalloids in communities surrounding the Chester-Trainer-Marcus Hook industrial area at levels that may exceed previous estimates from EPA modeling.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Arsénico , Metales Pesados , Selenio , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Monitoreo del Ambiente/métodos , Antimonio/análisis , Arsénico/análisis , Cadmio/análisis , Material Particulado/análisis , Polvo/análisis , Selenio/análisis , Vanadio/análisis , Aerosoles/análisis , Metalurgia , Metales Pesados/análisis
2.
Environ Sci Pollut Res Int ; 30(21): 59660-59675, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37014596

RESUMEN

Electrolytic manganese residue (EMR) and red mud (RM) are solid waste by-products of the metal manganese and alumina industries, respectively. Under long-term open storage, ammonia nitrogen and soluble manganese ions in EMR and alkaline substances in RM severely pollute and harm the environment. In order to alleviate the pollution problem of EMR and RM. In this study, the alkaline substances in RM were used to treat ammonia nitrogen and soluble manganese ions in EMR. The results confirm the following suitable treatment conditions for the mutual treatment of EMR and RM: EMR-RM mass ratio = 1:1, liquid-solid ratio = 1.4:1, and stirring time = 320 min. Under these conditions, the elimination ratios of ammonia nitrogen (emitted in the form of ammonia gas) and soluble manganese ions (solidified in the form of Mn3.88O7(OH) and KMn8O16) are 85.87 and 86.63%, respectively. Moreover, the alkaline substances in RM are converted into neutral salts (Na2SO4 and Mg3O(CO3)2), achieving de-alkalinisation. The treatment method can also solidify the heavy metal ions-Cr3+, Cu2+, Ni2+, and Zn2+-present in the waste residue with leaching concentrations of 1.45 mg/L, 0.099 mg/L, 0.294 mg/L, and 0.449 mg/L, respectively. This satisfies the requirements of the Chinese standard GB5085.3-2007. In the mutual treatment of EMR and RM, the kinetics of ammonia nitrogen removal and manganese-ion solidification reactions are controlled via a combination of membrane diffusion and chemical reaction mechanisms.


Asunto(s)
Amoníaco , Electrólitos , Manganeso , Amoníaco/química , Electrólitos/química , Iones , Manganeso/química , Nitrógeno/química , Metalurgia
3.
J Environ Radioact ; 251-252: 106987, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35981460

RESUMEN

The decommissioning of uranium mining and metallurgy facilities involves sensitive issues of the local government and the public, which is related to the vital interests of the surrounding residents. Improper disposal may lead to negative emotions among the public and affect the process of uranium mining and metallurgy facilities decommissioning projects. In order to explore the acceptance of uranium mining and metallurgy decommissioning projects by nearby residents and its influencing factors, a hypothesis model of influencing factors of public acceptance was constructed through literature survey. Taking the public around a uranium mining and metallurgy in Hunan Province as an example, a questionnaire survey was carried out. Using the AMOS21.0 tool, the fitting test of the structural equation model was carried out on 506 valid sample data and the hypothetical model, and the key factors affecting the public acceptance of the uranium mining and metallurgy decommissioning project were analyzed. The findings show that public perceived risk (-0.28), familiarity (0.26) and trust (0.175) are key factors influencing acceptance. The research results provide a methodological basis for improving the public acceptance of uranium mining and metallurgy decommissioning projects.


Asunto(s)
Monitoreo de Radiación , Uranio , Metalurgia , Minería , Uranio/análisis
4.
Sci Rep ; 12(1): 2693, 2022 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-35177739

RESUMEN

The global pandemic response to COVID-19 has led to the generation of huge volumes of unrecyclable plastic waste from single use disposable face coverings. Rotary hearth furnaces can be used to recover Zn and Fe from non-recyclable steelmaking by-product dusts, and waste plastic material such as facemasks could be utilized as a supplementary reductant for the rotary hearth furnace (RHF), but their fibrous form makes milling and processing to appropriate sizing for RHF application extremely challenging. A scalable method of grinding facemasks to powder by melting and mixing with Welsh coal dust reported herein provides a solution to both environmental challenges. The melt-blended PPE/coal dust shows a dramatically improved CO2 gasification reactivity (Ea = 133-159 kJmol-1) when compared to the untreated coal (Ea = 183-246 kJmol-1), because of improved pore development in the coal during the pyrolysis stage of heating and the catalytic activity of the CaO based ash present in the facemask plastic. The results are promising for the application of waste facemasks in recycling steelmaking by-product dusts in rotary hearth furnaces and may also be suitable for direct injection to the blast furnace subject to further study.


Asunto(s)
Industria del Carbón , Máscaras , Metalurgia , Reciclaje/métodos , Administración de Residuos/métodos
5.
Appl Radiat Isot ; 177: 109911, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34481316

RESUMEN

The bioleaching process is developing as an economic and successful biotechnology method in the metallurgy industry. Acidithiobacillus ferrooxidans is one of the most important bacteria involved in uranium bioleaching which converts insoluble U4+ to soluble U6+ by oxidation of Fe2+ to Fe3+ using several periplasmic proteins encoded by the genes in rus and petI operons in its electron transport pathway. Accordingly, the purpose of this study was to consider the expression of these genes through exposed A. ferrooxidans sp. FJ2 to γ-ray in 17 different doses targeting uranium extraction yield. Acidithiobacillus ferrooxidans sp. FJ2 was irradiated by gamma rays at 25, 50, 75, 100, 150, 300, 450, 600, 750 Gy and 1, 2, 5, 10, 15, 20, 25 and 30 kGy doses. Moreover, the Eh value of 9k culture media was measured as special screening criteria to select the four treatments. The selected bacteria were cultured in 9k media, containing 50% uranium ore powder in the bioleaching process. Then, the value of pH & Eh of culture media, Fe2+ and uranium concentrations in 4, 8 and 13 day's period of incubation were measured. In followings, the expression levels of cyc1, cyc2, rus, coxB, petA, petB, petC and cycA genes at the end of each period were investigated by real-time PCR. Overall, all samples demonstrated a decrease in pH value and Fe2+ concentration and an increase in Eh value and U concentration in time intervals. The gamma irradiation in given doses raised the expression levels of all genes encoded in rus and petI operons, except petB gene during the bioleaching process, although, it had no effect either on the pH, Eh values or on Fe2+ and uranium concentrations. This result implies that during the oxidation of ferrous iron and formation of Jarosite sediment, the decreasing trend of pH and the increasing trend of Eh occurred in all samples. However, the differences in expression of the genes of rus and petI operons in the samples did not have an effect on uranium extraction.


Asunto(s)
Acidithiobacillus/genética , Acidithiobacillus/efectos de la radiación , Proteínas Bacterianas/genética , Proteínas Bacterianas/efectos de la radiación , Operón/genética , Operón/efectos de la radiación , Uranio/aislamiento & purificación , Rayos gamma , Regulación Bacteriana de la Expresión Génica , Concentración de Iones de Hidrógeno , Metalurgia , Oxidación-Reducción
6.
PLoS One ; 16(7): e0254096, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34270592

RESUMEN

This paper presents a study on copper production and distribution in Lower Austria's southeastern region during the Late Bronze Age (c. 1350-800 BC), with the focal point being the chemistry and isotopic character of artifacts from a small copper mining site at Prigglitz-Gasteil on the Eastern Alps' easternmost fringe. Ores, casting cakes, and select objects from the Late Bronze Age mining site at Prigglitz-Gasteil, Lower-Austria, and within 15 km of its surroundings, were chemically and isotopically analysed using XRF, NAA, and MC-ICPMS. The importance of Prigglitz-Gasteil as a local mining and metal processing center is evaluated based on the produced data, and the distribution and sourcing of copper-producing materials found at the site are discussed. Special attention is paid to the mixing of scrap and source materials early in the metal production process. The most salient discussions focus on the variability of the chemistry and Pb isotopic ratios of the studied objects, which seem to constitute a multitude of source materials, unlike the pure chalcopyrite-source copper produced from the Prigglitz-Gasteil mine itself. The analytical data suggests that copper alloys were mainly imported from materials originating in the Slovakian Ore Mountains, which were subsequently mixed/recycled with relatively pure locally produced copper. The purity of the copper from Prigglitz-Gasteil was fortuitous in identifying imported copper that contained measurable amounts of Pb and other chemically distinct characteristics. The chaîne opératoire of metal production at the site is mentioned; however, it is clear that additional information on the region's geochemistry is required before any finite conclusions on the ore-to-metal production can be made.


Asunto(s)
Metalurgia/historia , Minería/historia , Austria , Evolución Cultural/historia , Historia Antigua , Humanos , Desarrollo Industrial/historia
7.
J Environ Manage ; 294: 113001, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34111595

RESUMEN

Yellow phosphorous flue dust (YPFD) is a solid waste produced by the yellow phosphorus industry that contains heavy metals such as zinc (Zn) and lead (Pb), causing environmental damage. In this work, a vacuum metallurgy method is proposed to separate and recover Zn and Pb from solid waste YPFD. Under optimized conditions of 1173 K, 30 wt% reductant dosage, 60 min, and 5-10 Pa, the pre-separation of Zn and Pb was realized and the recovery rates of Zn and Pb reached 92.47% and 99.78%, respectively. In addition, gallium (Ga) remained in the residue with little loss, and then recovered by raising the reaction temperature to 1323 K. The recovery rates of Ga reached 87.57%. The principle of metal volatilization under vacuum at different temperatures was also clarified. The thermodynamic calculations of the carbothermal reduction reaction of metal oxides under vacuum were carried out. The analysis of the product obtained at 1173 K showed that Zn and Pb mainly existed in the form of elemental or simple compounds. At 1323 K, Ga in the residue was highly enriched in the condensation zone, which is conducive for the subsequent purification. The whole process is short, there is no waste water, low levels of pollution of emitted, and the technology provides a clean and sustainable way to reuse YPFD.


Asunto(s)
Metales Pesados , Zinc , Polvo , Plomo , Metalurgia , Metales Pesados/análisis , Fósforo , Vacio , Zinc/análisis
8.
Int J Hyg Environ Health ; 235: 113775, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34058621

RESUMEN

The oxidative potential (OP) measures the ability of pollutants to oxidize a chemical/biological probe. Such assays are starting to gain acceptance as integrative exposure metrics associated with inflammatory-based pathologies. Diseases such as asthma, rhinitis or cancers are reported for workers exposed to oil mist, which are aerosols of metal working fluids (MWF) emitted during the machining of metals. Measuring oil mist in the air is challenging, and exposures are often quantified as the mass fraction, which does not account for exposures to the gaseous fraction. Consequently, exposures are underestimated and furthermore, the hazardous property of oil mist is not assessed. We postulate that it is more relevant to assess occupational exposures to the hazardous fractions of oil mist by measuring OP than by simply measuring mass. We characterized exposures to straight and water-based MWF among workers in the French and Swiss mechanical industry using standard methods for oil mist and the ferrous orange xylenol assay for OP assessment (OPFOX). Considering the particulate fraction, the water-based MWF presented the greatest OPFOX. The OP was associated with organic carbon and iron content. The gaseous fraction of the oil mist presented also an important redox activity, particularly in workshops where straight oils were used. The hexanal concentration was associated with this OPFOX. The OPFOX measurement is thus integrative of multiple parameters, and bring complementary information when assessing MWF exposures. Our results highlight that OPFOX account for MWF type and could be an interesting parameter to characterize such exposure.


Asunto(s)
Contaminantes Ocupacionales del Aire , Exposición Profesional , Aerosoles , Contaminantes Ocupacionales del Aire/análisis , Humanos , Exposición por Inhalación/análisis , Metalurgia , Exposición Profesional/análisis , Oxidación-Reducción , Estrés Oxidativo
9.
Radiat Environ Biophys ; 59(4): 703-710, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32970165

RESUMEN

Radiation monitoring is an important radiation safety measure implemented at the hydrometallurgical plant of the Stepnogorsk mining and chemical combine (HMP SMCC, Republic of Kazakhstan). Follow-up of the workers and their regular medical examinations has laid the basis to create a cohort with the potential to be used in radiation epidemiology. The aim of current pilot study was to analyze the dose forming factors for workers of HMP SMCC. For this, bioassays samples collected from 54 workers employed at eight HMP workshops were measured using the "Agilent 7800 ICP-MS" mass spectrometer. Three years later, measurements were repeated for four workers with the highest concentrations of uranium in urine. The results of site-specific measurements of dose rates, long-lived alpha-particle activity concentrations and equivalent equilibrium volume activity of radon were derived from the archive of the HMP SMCC Service of Radiation and Toxic Safety and analyzed to fully evaluate the radiation situation at those workplaces. Maximum urine uranium concentrations were measured for workers at the extraction workshop and mechanical repair shop (up to 26.7 µg/L and 14.6 µg/L, respectively). Urinary uranium from workers employed at other sites was mainly (for about 72% of the samples) in the range of values that may occur in natural conditions (< 0.4 µg/L). A wide individual variability in uranium concentration in urine samples (from 60% to 200% of CV) was found. A linear dependence of cumulative effective dose on work experience was found with a slope of 7.5 mSv per year. This slope did not depend on working place. For the investigated workers, cumulative effective doses of workers were found in the range of low (< 100 mSv) and medium doses (100-500 mSv). It is concluded that the newly created cohort of HMP SMCC workers has the potential to improve the knowledge on health effects from low- and medium doses of ionizing radiation.


Asunto(s)
Metalurgia , Exposición Profesional/análisis , Uranio/orina , Adulto , Anciano , Partículas alfa , Monitoreo Biológico , Humanos , Kazajstán , Masculino , Persona de Mediana Edad , Minería , Proyectos Piloto , Dosis de Radiación , Monitoreo de Radiación
10.
Sci Rep ; 10(1): 6746, 2020 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-32317769

RESUMEN

With the increase in iron/steel production, the higher volume of by-products (slag) generated necessitates its efficient recycling. Because the Linz-Donawitz (LD) slag is rich in silicon (Si) and other fertilizer components, we aim to evaluate the impact of the LD slag amendment on soil quality (by measuring soil physicochemical and biological properties), plant nutrient uptake, and strengthens correlations between nutrient uptake and soil bacterial communities. We used 16 S rRNA illumine sequencing to study soil bacterial community and APIZYM assay to study soil enzymes involved in C, N, and P cycling. The LD slag was applied at 2 Mg ha-1 to Japonica and Indica rice cultivated under flooded conditions. The LD slag amendment significantly improved soil pH, plant photosynthesis, soil nutrient availability, and the crop yield, irrespective of cultivars. It significantly increased N, P, and Si uptake of rice straw. The slag amendment enhanced soil microbial biomass, soil enzyme activities and enriched certain bacterial taxa featuring copiotrophic lifestyles and having the potential role for ecosystem services provided to the benefit of the plant. The study evidenced that the short-term LD slag amendment in rice cropping systems is useful to improve soil physicochemical and biological status, and the crop yield.


Asunto(s)
Fertilizantes/análisis , Consorcios Microbianos/efectos de los fármacos , Oryza/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Residuos/análisis , Actinobacteria/clasificación , Actinobacteria/genética , Actinobacteria/aislamiento & purificación , Alphaproteobacteria/clasificación , Alphaproteobacteria/genética , Alphaproteobacteria/aislamiento & purificación , Betaproteobacteria/clasificación , Betaproteobacteria/genética , Betaproteobacteria/aislamiento & purificación , Ciclo del Carbono/fisiología , Deltaproteobacteria/clasificación , Deltaproteobacteria/genética , Deltaproteobacteria/aislamiento & purificación , Firmicutes/clasificación , Firmicutes/genética , Firmicutes/aislamiento & purificación , Gammaproteobacteria/clasificación , Gammaproteobacteria/genética , Gammaproteobacteria/aislamiento & purificación , Humanos , Concentración de Iones de Hidrógeno , Hierro/metabolismo , Hierro/farmacología , Metalurgia/métodos , Consorcios Microbianos/fisiología , Ciclo del Nitrógeno/fisiología , Oryza/microbiología , Oryza/fisiología , Fósforo/fisiología , Fotosíntesis/fisiología , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/microbiología , Raíces de Plantas/fisiología , ARN Ribosómico 16S/genética , Silicio/metabolismo , Silicio/farmacología , Suelo/química , Microbiología del Suelo , Acero/química
11.
PLoS One ; 15(1): e0227259, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31968000

RESUMEN

The paper discusses results of an interdisciplinary research project integrating lead isotope, chemical, and archaeological analysis of 20 early metal objects from central Italy. The aim of the research was to develop robust provenance hypotheses for 4th and 3rd millennia BC metals from an important, yet hitherto neglected, metallurgical district in prehistoric Europe, displaying precocious copper mining and smelting, as well as socially significant uses of metals in 'Rinaldone-style' burials. All major (and most minor) ore bodies from Tuscany and neighbouring regions were characterised chemically and isotopically, and 20 Copper Age axe-heads, daggers and halberds were sampled and analysed. The objects were also reassessed archaeologically, paying special attention to find context, typology, and chronology. This multi-pronged approach has allowed us to challenge received wisdom concerning the local character of early metal production and exchange in the region. The research has shown that most objects were likely manufactured in west-central Italy using copper from Southern Tuscany and, quite possibly, the Apuanian Alps. A few objects, however, display isotopic and chemical signatures compatible with the Western Alpine and, in one case, French ore deposits. This shows that the Copper Age communities of west-central Italy participated in superregional exchange networks tying together the middle/upper Tyrrhenian region, the western Alps, and perhaps the French Midi. These networks were largely independent from other metal displacement circuits in operation at the time, which embraced the north-Alpine region and the south-eastern Alps, respectively.


Asunto(s)
Arqueología , Metalurgia/historia , Minería/historia , Aleaciones/historia , Entierro/historia , Carbón Mineral/historia , Cobre/historia , Geografía , Historia Antigua , Isótopos/análisis , Italia , Plomo/análisis
12.
Environ Geochem Health ; 42(12): 4113-4124, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31520319

RESUMEN

Active smelters release high concentration of multiple toxic metal(loid)s into the environment, degrading the soil cover and posing high risks to human health. The present study investigates Cu along with other metal(loids) such as As, Cd, Hg, Co, Mn, Pb and Zn in the soil collected from the vicinity of Cu smelter, Karabash, Russia, and potential health risks to local children and adults were assessed. The average concentrations of Cu, Zn, Pb, As, Cd, and Hg in the exposed soil were 2698, 1050, 702, 392, 9 and 2 mg kg-1, respectively, which was significantly (p < 0.05) much higher than reference soil: Cu(107), As(18), Cd(0.3), Hg(0.2), Pb(54) and Zn(125) mg kg-1. The enrichment factor (EF) for Cu, Hg, Pb and Zn showed significant enrichment, whereas very high enrichment was recorded for As (20.0) and Cd (27.6) suggesting the soil was severely affected by smelting activities. The pollution load index was tenfold higher than the acceptable level of one, whereas potential ecological risk factor showed very high potential risks of Cd and Hg, along with a considerable ecological risk of As and Cu. Very high ecological risk index of 1810 indicates severe degradation of environmental ecosystem. The results of EF, Pearson correlation and principle component analysis were complementary and suggest the anthropogenic source of contamination for Cu, As, Pb, Hg and Cd. The present result suggests As > Pb > Cu in the exposed soil were the major contributors for the health risks and account for 81%, 12% and 5%, and 77%, 12% and 8% of hazard quotient for children and adults, respectively. Noticeably, the health risks to local children dwelling in the vicinity of Cu smelter were 12 and 20 times higher than to adult and the acceptable level of one, respectively. Therefore, in order to reduce the health risk due to metal(loid)s, mitigation measures are needed to remediate the pollution of the exposed soil.


Asunto(s)
Metaloides/análisis , Metalurgia , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Cobre/análisis , Cobre/toxicidad , Monitoreo del Ambiente , Humanos , Metaloides/toxicidad , Metales Pesados/toxicidad , Medición de Riesgo , Federación de Rusia , Suelo/química , Contaminantes del Suelo/toxicidad
13.
J Biosci ; 44(3)2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31389357

RESUMEN

The Indo-European debate has been going on for a century and a half. Initially confined to linguistics, race-based anthropology and comparative mythology, it soon extended to archaeology, especially with the discovery of the Harappan civilization, and peripheral disciplines such as agriculture, archaeometallurgy or archaeoastronomy. The latest entrant in the field, archaeogenetics, is currently all but claiming that it has finally laid to rest the whole issue of a hypothetical migration of Indo-Aryan speakers to the Indian subcontinent in the second millennium BCE. This paper questions the finality of this claim by pointing to inherent limitations, methodological issues and occasional biases in current studies as well as in the interpretation of archaeological evidence.


Asunto(s)
Pueblo Asiatico/historia , Etnicidad , Migración Humana/tendencias , Lenguaje/historia , Lingüística/métodos , Población Blanca/historia , Agricultura/historia , Antropología/métodos , Arqueología/métodos , Astronomía/historia , Femenino , Variación Genética , Genética de Población , Historia Antigua , Humanos , India/etnología , Masculino , Metalurgia/historia
14.
PLoS One ; 14(7): e0219574, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31339904

RESUMEN

The rich and long-lasting Nordic Bronze Age was dependent throughout on incoming flows of copper and tin. The crucial turning point for the development of the NBA can be pinpointed as the second phase of the Late Neolithic (LN II, c. 2000-1700 BC) precisely because the availability and use of metal increased markedly at this time. But the precise provenance of copper reaching Scandinavia in the early second millennium is still unclear and our knowledge about the driving force leading to the establishment of the Bronze Age in southern Scandinavia is fragmentary and incomplete. This study, drawing on a large data set of 210 samples representing almost 50% of all existing metal objects known from this period in Denmark, uses trace element (EDXRF) and isotope analyses (MC-ICP-MS) of copper-based artifacts in combination with substantial typological knowledge to profoundly illuminate the contact directions, networks and routes of the earliest metal supplies. It also presents the first investigation of local recycling or mixing of metals originating from different ore regions. Both continuity and change emerge clearly in the metal-trading networks of the Late Neolithic to the first Bronze Age period. Artifacts in LN II consist mainly of high-impurity copper (so-called fahlore type copper), with the clear exception of British imports. Targeted reuse of foreign artifacts in local production is demonstrated by the presence of British metal in local-style axes. The much smaller range of lead isotope ratios among locally crafted compared to imported artifacts is also likely due to mixing. In the latter half of Nordic LN II (1800-1700 BC), the first signs emerge of a new and distinct type of copper with low impurity levels, which gains enormously in importance later in NBA IA.


Asunto(s)
Metalurgia , Artefactos , Análisis por Conglomerados , Historia Antigua , Isótopos , Metalurgia/historia , Análisis de Componente Principal , Países Escandinavos y Nórdicos , Oligoelementos/análisis
15.
Molecules ; 24(12)2019 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-31248081

RESUMEN

A method for processing of metallurgical waste materials (chemically defined as sulfur-bearing zinc-ferric materials) produced by plants processing zinc ores and their concentrates is proposed. The method proposed is a combination of pyro- and hydrometallurgical treatments of the waste material. The crucial steps in the developed method include: roasting the material at 450 °C to generate sulfur dioxide (SO2), absorption of SO2 in an aqueous system to form sulfuric acid (IV), carbothermic decomposition of zinc ferrite compounds, and leaching of zinc from the roasted material using sulfuric (IV) acid. The method allows one to extract up to 40% of zinc from the waste material and, consequently, to generate a fraction of material with substantially higher content of iron oxides. The proposed method takes advantage of the presence of sulfur in the processed material which upon roasting is converted to sulfuric acid (IV)-a leaching agent for selective extraction of zinc. The properly adjusted pH of the aqueous medium in which the leaching process is carried out is the key factor determining the quantitative and selective separation of zinc. If the amount of sulfur in the processed material is insufficient, it may be supplemented by adding sulfuric acid (VI) to adjust the pH. The method proposed was tested at a laboratory scale and quarter industrial scale using the real samples taken from stockpiles in the vicinity of the plant processing zinc and lead ores in Poland. It may also work for any zinc-ferric materials from various sources.


Asunto(s)
Plomo/química , Metalurgia , Residuos , Zinc/química , Zinc/aislamiento & purificación , Compuestos Férricos/química , Residuos Industriales , Metalurgia/métodos , Análisis Espectral
16.
World J Microbiol Biotechnol ; 35(5): 69, 2019 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-31011888

RESUMEN

The filamentous Bipolaris and Curvularia genera consist of species known to cause severe diseases in plants and animals amounting to an estimated annual loss of USD $10 billion worldwide. Despite the harmful effect of Bipolaris and Curvularia species, scarce attention is paid on beneficial areas where the fungi are used in industrial processes to generate biotechnological products. Catalytic potential of Bipolaris and Curvularia species in the production of biodiesel, bioflucculant, biosorbent, and mycoherbicide are promising for the bioeconomy. It is herein demonstrated that knowledge-based application of some endophytic Bipolaris and Curvularia species are indispensable vectors of sustainable economic development. In the twenty-first century, India, China, and the USA have taken progress in the biotechnological application of these fungi to generate wealth. As such, some Bipolaris and Curvularia species significantly impact on global crop improvement, act as catalyst in batch-reactors for biosynthesis of industrial enzymes and medicines, bioengineer of green-nanoparticle, agent of biofertilizer, bioremediation and bio-hydrometallurgy. For the first time, this study discusses the current advances in biotechnological application of Bipolaris and Curvularia species and provide new insights into the prospects of optimizing their bioengineering potential for developing bioeconomy.


Asunto(s)
Ascomicetos , Bioingeniería , Biotecnología , Endófitos , Ascomicetos/clasificación , Ascomicetos/enzimología , Ascomicetos/metabolismo , Biodegradación Ambiental , Biocombustibles , Agentes de Control Biológico , Biotransformación , Endófitos/clasificación , Endófitos/enzimología , Endófitos/metabolismo , Fertilizantes , Floculación , Virus Fúngicos , Herbicidas , Metalurgia , Nanopartículas , Suelo/química , Simbiosis , Termotolerancia , Uranio
17.
J Environ Manage ; 232: 625-635, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30530272

RESUMEN

The aim of this study was to evaluate the biodegradation potential of microbiota isolated from different environmental niches towards different types of metalworking fluids (MWF). The first experimental stage was focused on the assessment of biochemical oxygen demand reduction efficiency of autochthonous and environmental microbial communities. Based on the obtained results, the following order describing the biodegradation potential of communities from the studied niches was established: petroleum contaminated soil > waste repository ≥ waste MWF tanks > pesticide-treated field > activated sludge > municipal sewage effluents. For comparative purposes, the most efficient community originating from petroleum contaminated soil (PCS1) was selected for further studies along with the most efficient community originating from a waste MWF tank (WMT1). The studied communities achieved 100% biodegradation efficiency of decanedioic and dodecanedioic acids as well as glycerine and polyethoxylated dodecanol. However, the PCS1 community was more versatile and displayed significantly higher biodegradation efficiency of mineral oil (80% compared to 50% in case of WMT1). Similarly, experiments using pristine and spent MWF solutions confirmed that the PCS1 community outperformed the WMT1 community during the biodegradation of MWF containing oil as the main component (COD reduction of 80, 60 and 30% in case of semi-synthetic MWF, soluble oil and spent MWF, respectively). Results of community dynamics assessment using quantitative real-time PCR after the biodegradation of different types of MWF confirmed that the PCS1 community was characterized by high genetic stability and allowed to indicate the potential 'key players'.


Asunto(s)
Metalurgia , Petróleo , Biodegradación Ambiental , Aguas del Alcantarillado
18.
Proc Natl Acad Sci U S A ; 115(25): E5661-E5668, 2018 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-29844161

RESUMEN

The Balkans are considered the birthplace of mineral resource exploitation and metalworking in Europe. However, since knowledge of the timing and extent of metallurgy in southeastern Europe is largely constrained by discontinuous archaeological findings, the long-term environmental impact of past mineral resource exploitation is not fully understood. Here, we present a high-resolution and continuous geochemical record from a peat bog in western Serbia, providing a clear indication of the extent and magnitude of environmental pollution in this region, and a context in which to place archaeological findings. We observe initial evidence of anthropogenic lead (Pb) pollution during the earliest part of the Bronze Age [∼3,600 years before Common Era (BCE)], the earliest such evidence documented in European environmental records. A steady, almost linear increase in Pb concentration after 600 BCE, until ∼1,600 CE is observed, documenting the development in both sophistication and extent of southeastern European metallurgical activity throughout Antiquity and the medieval period. This provides an alternative view on the history of mineral exploitation in Europe, with metal-related pollution not ceasing at the fall of the western Roman Empire, as was the case in western Europe. Further comparison with other Pb pollution records indicates the amount of Pb deposited in the Balkans during the medieval period was, if not greater, at least similar to records located close to western European mining regions, suggestive of the key role the Balkans have played in mineral resource exploitation in Europe over the last 5,600 years.


Asunto(s)
Monitoreo del Ambiente/historia , Monitoreo del Ambiente/estadística & datos numéricos , Contaminación Ambiental/historia , Contaminación Ambiental/estadística & datos numéricos , Plomo/efectos adversos , Plomo/química , Arqueología/historia , Arqueología/estadística & datos numéricos , Peninsula Balcánica , Ambiente , Europa (Continente) , Historia del Siglo XVI , Historia Antigua , Metalurgia/historia , Metalurgia/estadística & datos numéricos , Minerales/efectos adversos , Minerales/química , Minería/historia , Minería/estadística & datos numéricos , Suelo/química , Contaminantes del Suelo/efectos adversos , Contaminantes del Suelo/química
19.
Environ Sci Pollut Res Int ; 25(18): 18130-18137, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29691750

RESUMEN

The aim of this work was to study Cr, Ni, Zn, and P bioaccumulation in different compartments of Typha domingensis plants and sediment in a free-water surface constructed wetland for the treatment of a metallurgical effluent for 5 years. Removal efficiencies were satisfactory. To increase metal tolerance, its transport from belowground to aboveground tissues is reduced, being metal concentrations in the roots and rhizomes significantly higher than in the aerial and submerged parts of leaves. Regarding belowground tissues, metals were retained in the roots, while P was mainly accumulated in rhizomes. Bioaccumulation factors (BAFs) of Cr and Ni showed values near 1, and BAF of Zn and P were above 1 in several samplings, indicating bioaccumulation in the roots. Translocation factors (TFs) of Cr, Ni, and Zn were below 1, showing a scarce translocation from the roots to the aerial parts of the leaves, while the TF of P were above 1 in many samplings, indicating that this element is necessary for plant metabolism. The study of plant tissues where contaminants are accumulated allows gaining insight into the constructed wetland operation. The high translocation of P in T. domingensis makes this species suitable for its phytoextraction, while the low metal translocation makes T. domingensis suitable for phytostabilization.


Asunto(s)
Cromo/análisis , Níquel/análisis , Fósforo/análisis , Typhaceae/metabolismo , Humedales , Zinc/análisis , Argentina , Biodegradación Ambiental , Cromo/metabolismo , Metalurgia , Níquel/metabolismo , Fósforo/metabolismo , Typhaceae/crecimiento & desarrollo , Zinc/metabolismo
20.
Hum Exp Toxicol ; 37(4): 350-357, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28441892

RESUMEN

The aim of this study was to assess changes in bone mineral density (BMD) and cadmium (Cd) levels in blood and urine in individuals living in a Cd-contaminated area according to the type of osteoporosis medication over a three-year period. This follow-up study included 204 residents living in the vicinity of a closed copper refinery, who had been found to have elevated urinary or blood Cd levels. Cd levels in the blood and urine, as well as BMD, were measured every 6 months. After the first BMD measurement, individuals were prescribed antiresorptives such as alendronate or vitamin D and calcium, according to their BMD. Subjects were classified according to the type of medicine provided over the previous 6 months. General linear models controlling for other factors were used to evaluate the effects of each type of medication on the participants' Cd levels and BMD. Spinal BMD showed a significant increase in the antiresorptive group compared to the nontreatment group. Significant decreases in blood Cd levels were found in the vitamin D and calcium group, in comparison to the nontreatment group, as well as a marginally significant decrease in the antiresorptive group. The vitamin D and calcium group showed a significantly greater decrease in urinary Cd levels than the nontreatment group. In contrast, antiresorptive medication was found to have a negative effect on urinary Cd excretion. These results suggest that vitamin D and calcium treatment for osteoporosis lowers blood Cd levels more effectively and improves urinary Cd excretion.


Asunto(s)
Alendronato/uso terapéutico , Conservadores de la Densidad Ósea/uso terapéutico , Densidad Ósea/efectos de los fármacos , Cadmio/sangre , Cadmio/orina , Calcio/uso terapéutico , Suplementos Dietéticos , Contaminantes Ambientales/sangre , Contaminantes Ambientales/orina , Osteoporosis/tratamiento farmacológico , Vitamina D/uso terapéutico , Absorciometría de Fotón , Anciano , Carga Corporal (Radioterapia) , Cobre , Femenino , Humanos , Masculino , Metalurgia , Persona de Mediana Edad , Osteoporosis/diagnóstico , Osteoporosis/fisiopatología , Eliminación Renal , República de Corea , Factores de Tiempo , Resultado del Tratamiento
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA