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1.
Environ Monit Assess ; 193(4): 208, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33755795

RESUMO

Increasing gaseous emissions of nitrogen (N) and sulfur (S) associated with oil sands development in northern Alberta (Canada) has led to changing regional wet and dry N and S deposition regimes. We assessed the potential for using bog plant/lichen tissue chemistry (N and S concentrations, C:N and C:S ratios, in 10 plant/lichen species) to monitor changing atmospheric N and S deposition through sampling at five bog sites, 3-6 times per growing season from 2009 to 2016. During this 8-year period, oil sands N emissions steadily increased, while S emissions steadily decreased. We examined the following: (1) whether each species showed changes in tissue chemistry with increasing distance from the Syncrude and Suncor upgrader stacks (the two largest point sources of N and S emissions); (2) whether tissue chemistry changed over the 8 year period in ways that were consistent with increasing N and decreasing S emissions from oil sands facilities; and (3) whether tissue chemistry was correlated with growing season wet deposition of NH4+-N, NO3--N, or SO42--S. Based on these criteria, the best biomonitors of a changing N deposition regime were Evernia mesomorpha, Sphagnum fuscum, and Vaccinium oxycoccos. The best biomonitors of a changing S deposition regime were Evernia mesomorpha, Cladonia mitis, Sphagnum fuscum, Sphagnum capillifolium, Vaccinium oxycoccos, and Picea mariana. Changing N and S deposition regimes in the oil sands region appear to be influencing N and S cycling in what once were pristine ombrotrophic bogs, to the extent that these bogs may effectively monitor future spatial and temporal patterns of deposition.


Assuntos
Líquens , Áreas Alagadas , Alberta , Ascomicetos , Monitoramento Ambiental , Nitrogênio/análise , Campos de Petróleo e Gás , Parmeliaceae , Enxofre/análise
2.
Ecotoxicol Environ Saf ; 209: 111790, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33316728

RESUMO

AIMS: The objective of the present study was to elucidate the effects of sulfur (S) application on selenium (Se) uptake and seed Se speciation in high-protein soybean (Glycine max L.) grown in different soil types. METHODS: Pot experiments were conducted with soybean plants grown in yellow-brown soil (pH 5.68) and in calcareous alluvial soil (pH 7.87). Sodium selenate (Na2SeO4, 2 mg kg-1) was applied to soil with or without S fertilizer (S, 100 mg kg-1). RESULTS: Soybean grain yield and total biomass in calcareous alluvial soil were both approximately 1.3-fold the levels in yellow-brown soil. Following Se application, seed Se concentration in calcareous alluvial soil was 3.2-fold the concentration in yellow-brown soil, although additional S application reduced the corresponding seed Se concentrations by 55.6% and 38.6%, respectively. Generally, Se application facilitated Se translocation and enrichment in soybean seeds. Organic Se accounted for 92% of seed total Se and Se-methionine (>90%) was always the major Se species. Available Se (soluble and exchangeable fractions) accounted for 50.7% (yellow-brown soil) and 70.1% (calcareous alluvial soil) of soil total Se under Se treatment, while additional S application decreased the corresponding proportion of soluble Se by 12.6% and 14.4%. CONCLUSIONS: The bioavailability of selenate in calcareous alluvial soil was higher than the bioavailability in yellow-brown soil and was more negatively affected by S application. Although S application inhibited Se uptake in soybean plants in both soil types, it did not influence seed Se speciation and Se-methionine was the major Se species.


Assuntos
Selênio/metabolismo , Poluentes do Solo/metabolismo , Soja/fisiologia , Enxofre/análise , Disponibilidade Biológica , Transporte Biológico , Grão Comestível/química , Fertilizantes/análise , Sementes/química , Ácido Selênico , Selenometionina , Solo , Poluentes do Solo/análise
3.
Ecotoxicol Environ Saf ; 207: 111216, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32916525

RESUMO

Low concentrations of selenium (Se) are beneficial for plant growth. Foliar Se application at high concentrations is toxic to plants due to the formation of reactive oxygen species (ROS). This study characterized Se toxicity symptoms using X-ray fluorescence (XRF) technique in response to foliar Se application in cowpea plants. Five Se concentrations (0, 10, 25, 50, 100 e 150 g ha-1) were sprayed on leaves as sodium selenate. The visual symptoms of Se toxicity in cowpea leaves were separated into two stages: I) necrotic points with an irregular distribution and internerval chlorosis at the leaf limb border (50-100 g ha-1); II) total chlorosis with the formation of dark brown necrotic lesions (150 g ha-1). Foliar Se application at 50 g ha-1 increased photosynthetic pigments and yield. Ultrastructural analyses showed that Se foliar application above 50 g ha-1 disarranged the upper epidermis of cowpea leaves. Furthermore, Se application above 100 g ha-1 significantly increased the hydrogen peroxide concentration and lipid peroxidation inducing necrotic leaf lesions. Mapping of the elements in leaves using the XRF revealed high Se intensity, specifically in leaf necrotic lesions accompanied by calcium (Ca) as a possible attenuating mechanism of plant stress. The distribution of Se intensities in the seeds was homogeneous, without specific accumulation sites. Phosphorus (P) and sulfur (S) were found primarily located in the embryonic region. Understanding the factors involved in Se accumulation and its interaction with Ca support new preventive measurement technologies to prevent Se toxicity in plants.


Assuntos
Selênio/metabolismo , Vigna/metabolismo , Peroxidação de Lipídeos , Fósforo/análise , Fotossíntese , Folhas de Planta/química , Sementes/química , Ácido Selênico/análise , Selênio/análise , Enxofre/análise
4.
Ecotoxicol Environ Saf ; 200: 110758, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32497991

RESUMO

This study attempts to identify the influence of various aspects of human activities in three medium-sized Central European cities (Cottbus, Germany; Nitra, Slovakia and Slupsk, Poland) on air contamination. For comparison purposes, bark of Pinus sylvestris L. was collected from polluted and non-polluted urban areas. Nine elements: Fe, Mn, Cu, Zn, Ni, Cd, Cr, Pb and S were determined using microwave plasma atomic emission spectrometry, flame atomic absorption spectrometry and elementary analyzer. Results of the study showed significant differences between the cities in term of elements content in pine bark. The differences reflected well specific character of the cities and various effects of human activity. Study revealed that elements spatial variability among the cities is driven by the factor loadings character and reflects various emission sources and their impact range.


Assuntos
Poluentes Atmosféricos/análise , Metais Pesados/análise , Pinus sylvestris/química , Cidades , Monitoramento Ambiental , Alemanha , Humanos , Pinus , Casca de Planta/química , Polônia , Eslováquia , Enxofre/análise
5.
PLoS One ; 15(6): e0234053, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32484834

RESUMO

The efficient (site-specific) management of soil nutrients is possible by understanding the spatial variability in distribution of phyto-available nutrients (here after called available nutrients) and identifying the soil management zones (MZs) of agricultural landscapes. There is need for delineating soil MZs of agricultural landscapes of the world for efficient management of soil nutrients in order to obtain sustainability in crop yield. The present study was, therefore, undertaken to understand the spatial distribution pattern of available micronutrients (zinc (Zn), boron (B), iron (Fe), manganese (Mn) and copper (Cu)), available sulphur (S), and soil properties (soil acidity (pH), electrical conductivity (EC) and organic carbon (SOC) content) in soils of intensively cultivated Indo-Gangetic Plain (IGP) of India and to delineate soil MZs for efficient management of soil nutrients. Totally, 55101 soil samples from 0-15 cm depth were obtained from 167 districts of IGP during 2014 to 2017 and were analysed for different soil parameters. Soil pH, EC and SOC content varied from 4.44 to 9.80, 0.02 to 2.13 dS m-1 and 0.10 to 1.99%, respectively. The concentration of available Zn, B, Fe, Mn, Cu and S varied from 0.01 to 3.27, 0.01 to 3.51, 0.19 to 55.7, 0.05 to 49.0, 0.01 to 5.29 and 1.01 to 108 mg kg-1, respectively. Geostatistical analysis resulted in varied distribution pattern of studied soil parameters with moderate to strong spatial dependence. The extent (% area) of nutrient deficiencies in IGP followed the order: S > Zn > B > Mn > Cu > Fe. Principal component analysis and fuzzy c-means clustering produced six distinctly different soil MZs of IGP for implementation of zone-specific soil nutrient management strategies for attaining sustainability in crop yield. The developed MZ maps could also be utilized for prioritization and rationalization of nutrients supply in IGP of India.


Assuntos
Monitoramento Ambiental , Micronutrientes/análise , Solo/química , Análise Espacial , Enxofre/análise , Índia , Chuva , Estatística como Assunto
6.
Nat Commun ; 11(1): 1942, 2020 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-32327645

RESUMO

Dimethylsulfoniopropionate (DMSP) is a pivotal compound in marine biogeochemical cycles and a key chemical currency in microbial interactions. Marine bacteria transform DMSP via two competing pathways with considerably different biogeochemical implications: demethylation channels sulfur into the microbial food web, whereas cleavage releases sulfur into the atmosphere. Here, we present single-cell measurements of the expression of these two pathways using engineered fluorescent reporter strains of Ruegeria pomeroyi DSS-3, and find that external DMSP concentration dictates the relative expression of the two pathways. DMSP induces an upregulation of both pathways, but only at high concentrations (>1 µM for demethylation; >35 nM for cleavage), characteristic of microscale hotspots such as the vicinity of phytoplankton cells. Co-incubations between DMSP-producing microalgae and bacteria revealed an increase in cleavage pathway expression close to the microalgae's surface. These results indicate that bacterial utilization of microscale DMSP hotspots is an important determinant of the fate of sulfur in the ocean.


Assuntos
Regulação Bacteriana da Expressão Gênica , Água do Mar/microbiologia , Compostos de Sulfônio/metabolismo , Enxofre/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Redes e Vias Metabólicas/genética , Microalgas/metabolismo , Interações Microbianas , Fitoplâncton/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Rhodobacteraceae/genética , Rhodobacteraceae/metabolismo , Água do Mar/química , Análise de Célula Única , Compostos de Sulfônio/análise , Enxofre/análise , Transcrição Genética
7.
Environ Sci Technol ; 54(9): 5376-5384, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32250108

RESUMO

Particle emissions from marine traffic affect significantly air quality in coastal areas and the climate. The particle emissions were studied from a 1.4 MW marine engine operating on low-sulfur fuels natural gas (NG; dual-fuel with diesel pilot), marine gas oil (MGO) and marine diesel oil (MDO). The emitted particles were characterized with respect to particle number (PN) emission factors, PN size distribution down to nanometer scale (1.2-414 nm), volatility, electric charge, morphology, and elemental composition. The size distribution of fresh exhaust particles was bimodal for all the fuels, the nucleation mode highly dominating the soot mode. Total PN emission factors were 2.7 × 1015-7.1 × 1015 #/kWh, the emission being the lowest with NG and the highest with MDO. Liquid fuel combustion generated 4-12 times higher soot mode particle emissions than the NG combustion, and the harbor-area-typical lower engine load (40%) caused higher total PN emissions than the higher load (85%). Nonvolatile particles consisted of nanosized fuel, and spherical lubricating oil core mode particles contained, e.g., calcium as well as agglomerated soot mode particles. Our results indicate the PN emissions from marine engines may remain relatively high regardless of fuel sulfur limits, mostly due to the nanosized particle emissions.


Assuntos
Gás Natural , Navios , Gasolina/análise , Tamanho da Partícula , Material Particulado/análise , Enxofre/análise , Emissões de Veículos/análise
8.
Microbiol Res ; 236: 126453, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32155560

RESUMO

Sulfate related water quality and trophic status are crucial to operation of water diversion. Though the sulfur geochemistry in the lake sediment have been well studied, the effective indicator of surrounding environment conditions related to sulfur in river-lake systems are still unknown. In this study, Dongping Lake (DPH), Weishan Lake (WSH), and Hanzhuang trunk canal (HZQ) were selected as the typical river-lake systems in the eastern of China. Different spatial variations in sedimentary sulfate, total sulfur, and elemental composition of sediments were investigated in these areas. The relatively high sulfate in surface water and sediments appeared in portions of WSH. The biodiversity of HZQ and WSH surface sediments was much higher than that of DPH. Pseudomonas, Acinetobacter, and Thiobacillus were the dominant genera of the river-lake systems. Among the different genera in distribution, genera such as Malikia, Sulfurovum and Lysinibacillus were significantly negatively correlated with sulfur related environmental factors. While the genera such as Pseudomonas, Vogesella and Acinetobacter were significantly positively correlated with these factors. Compared with connectivity in the largest interaction network, bacteria such as Proteus, Acidobacter and Chlorobacteria were identified as indicatory taxa to infer sulfate related conditions in the river-lake systems.


Assuntos
Bactérias , Lagos/química , Rios/química , Espécies Sentinelas , Enxofre/análise , Bactérias/classificação , Bactérias/genética , Biodiversidade , China , Genes Bacterianos , Sedimentos Geológicos/química , Sedimentos Geológicos/microbiologia , Lagos/microbiologia , Metagenômica , Microbiota/genética , Filogenia , RNA Ribossômico 16S , Rios/microbiologia , Espécies Sentinelas/classificação , Espécies Sentinelas/genética , Poluentes Químicos da Água/análise
9.
Anal Bioanal Chem ; 412(6): 1353-1363, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31900540

RESUMO

The study of biologically important Cu2+ and S2- ions has drawn great attention in the recent years since an abnormal level of these ions is an indication for health impairment. Therefore, a reliable strategy for effective fluorescence determination of Cu2+ and S2- ions was developed. Simply, the method based on economical plant-dependent thermolysis procedure for efficient green synthesis of water dispersible luminescent polyamine-based carbon dots (PA@C-dots) utilizes Vitis vinifera juice as precursor with a high quantum yield (32.1%) and good photo-stability. The fluorescent PA@C-dots were characterized by different spectroscopical, physical, and structural techniques. Furthermore, the synthesized PA@C-dots can be used as an efficient dual functional fluorescent probe for the sensitive and selective estimation of Cu2+ and S2- ions. The incorporation of Cu2+ ions and their adsorption on the surface of PA@C-dot skeleton leads to the respectable fluorescence quenching of C-dots (turn-off mode). The Cu2+-PA@C-dot was found to be sensitive to S2- ions. The addition of S2- recovers the fluorescence (turn-on mode) of Cu2+-PA@C-dots, thanks to its capacity for withdrawing Cu2+ from the shell of PA@C-dots. Fluorescence quenching in the range of 0.07-60 µM Cu2+ was obtained with LOD and LOQ of 0.02 and 0.066 µM, respectively. Sulfide detection provides linearity in the range of 0.8 to 95 µM with LOD and LOQ of 0.24 and 0.79 µM, respectively. The optimal excitation and emission wavelengths for all experiments are 435 nm and 498 nm, respectively. Experiment results elucidate that the proposed method is suitable for Cu2+and S2- ion detection in environmental water samples. Graphical abstract Green synthesis of polyamine-functionalized nanoprobe by thermolysis method from plant source as bifunctional sensing platform for determination of Cu2+ and S2- in environmental water samples.


Assuntos
Carbono/química , Cobre/análise , Química Verde , Poliaminas/química , Pontos Quânticos/química , Enxofre/análise , Limite de Detecção , Microscopia Eletrônica de Transmissão , Difração de Pó , Análise Espectral/métodos , Vitis/química
10.
J Synchrotron Radiat ; 27(Pt 1): 60-66, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31868737

RESUMO

A new Rococo 2 X-ray fluorescence detector was implemented into the cryogenic sample environment at the Hard X-ray Micro/Nano-Probe beamline P06 at PETRA III, DESY, Hamburg, Germany. A four sensor-field cloverleaf design is optimized for the investigation of planar samples and operates in a backscattering geometry resulting in a large solid angle of up to 1.1 steradian. The detector, coupled with the Xspress 3 pulse processor, enables measurements at high count rates of up to 106 counts per second per sensor. The measured energy resolution of ∼129 eV (Mn Kα at 10000 counts s-1) is only minimally impaired at the highest count rates. The resulting high detection sensitivity allows for an accurate determination of trace element distributions such as in thin frozen hydrated biological specimens. First proof-of-principle measurements using continuous-movement 2D scans of frozen hydrated HeLa cells as a model system are reported to demonstrate the potential of the new detection system.


Assuntos
Espectrometria por Raios X/instrumentação , Síncrotrons , Cálcio/análise , Cloretos/análise , Criopreservação , Eletrodos , Desenho de Equipamento , Células HeLa/química , Humanos , Fósforo/análise , Potássio/análise , Compostos de Silício , Espectrometria por Raios X/métodos , Enxofre/análise , Raios X
11.
Environ Pollut ; 258: 113682, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31812529

RESUMO

The active use of solid fossil fuels (coal) in the production of heat and electricity has led to significant pollution, climate change, environmental degradation, and an increase in morbidity and mortality. Many countries (in particular, European ones, China, Japan, the USA, Canada, etc.) have launched programs for using plant and agricultural raw materials to produce heat and electricity by burning them instead of or together with traditional fuels. It is a promising solution to produce slurry fuels, based on a mixture of coal processing, oil refining and agricultural waste. This paper presents the results of experimental research into the formation and assessment of the most hazardous emissions (sulfur and nitrogen oxides) from the combustion of promising coal slurry fuels with straw, sunflower and algae additives, i.e. the most common agricultural waste. A comparative analysis has been carried out to identify the differences in the concentrations of sulfur and nitrogen oxides from the combustion of typical coal, coal processing waste, as well as fuel slurries with and without plant additives. It has been shown that the concentration of sulfur and nitrogen oxides can be reduced by 62-87% and 12-57%, respectively, when using small masses of plant additives (no more than 10 wt%) and maintaining high combustion heat of the slurry fuel. However, the use of algae and straw in the slurry composition can increase the HCl emissions, which requires extra measures to fight corrosion. A generalizing criterion of slurry fuel vs. coal efficiency has been formulated to illustrate significant benefits of adding plant solid waste to coal-water slurries containing petrochemicals. Straw and sunflower waste (10 wt%) were found to be the best additives to reduce the air pollutant emissions.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Carvão Mineral , Óxidos de Nitrogênio/análise , Enxofre/análise , Canadá , China , Helianthus , Japão , Feófitas , Caules de Planta , Água
12.
Sci Total Environ ; 703: 135591, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31767317

RESUMO

In Antarctica, penguins transport sulfur and other bio-elements in the form of guano from marine to terrestrial environments where they become deposited in ornithogenic soils and sediments, including lake or pond systems. Transformation of sulfur species in these terrestrial and aquatic deposits, however, has rarely been studied. Here, we used the cold diffusion method to analyze various sulfur species in a lake deposit of ornithogenic sediment core (C1) and a pristine lake sediment core (C2), collected from Ardley Island and Fildes Peninsula, Antarctic Peninsula, respectively. The total organic carbon, total phosphorus, total nitrogen and various sulfur species in C1 were more fluctuant and much higher than those in C2, indicating a primary source from penguin guano. In core C1, organic sulfur (Org-S) was the main form of sulfur, and sulfate (SO42-) was the main form of inorganic sulfur. The acid volatile sulfur (AVS) in C1 was much higher than pyrite sulfur (CRS). In the pristine lake sediment core C2, Org-S and SO42- were the main sulfur species. CRS was the primary form of reduced inorganic sulfur in C2 sediments in contrast to the AVS in C1, indicating that AVS had been effectively transformed into CRS in C1. Our results demonstrate that the high levels of organic matter in C1 likely limited the transformation of AVS to CRS.


Assuntos
Monitoramento Ambiental , Lagos/química , Enxofre/análise , Poluentes Químicos da Água/análise , Animais , Regiões Antárticas , Sedimentos Geológicos/química , Ilhas , Fósforo , Spheniscidae
13.
J Sci Food Agric ; 100(2): 785-793, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31612485

RESUMO

BACKGROUND: Red onion is popular in cuisines worldwide and is valued for its potential medicinal properties. Red onion is an important source of several phytonutrients such as flavonoids, thiosulfinates and other sulfur compounds, recognized as important elements of the diet. Nowadays, there is the need of producing food enriched in health benefit compounds. In this study, pads of sulfur bentonite (SB) with the addition of orange residue (OR) or olive pomace (OP) were used to improve the quality of red onion. The experiment was conducted for 3 months in the field to evaluate the phytochemicals of differently amended red onion. RESULTS: Treated plants were better in quality than controls. Antioxidant activity, detected as DPPH, ORAC and ABTS, was highest in plants grown in the presence of SB enriched with agricultural wastes, particularly SB-OR. Polyphenols increased in all treated plants. The volatile fraction was clearly dominated by sulfur compounds that are strictly related to the concentration of the aroma precursors S-alkenyl cysteine sulfoxides. The greater amount of thiosulfinates in treated compared with untreated onion evidenced that SB pelletized with agricultural wastes can represent a new formulation of organic fertilizer able to improve the beneficial properties of onion. The results highlighted that the best red onion quality was obtained using SB-OR pads. CONCLUSION: The use of SB bound with agricultural wastes represents a novel strategy to increase bio-compounds with beneficial effects on human health, to enhance the medical and economic values of sulfur-loving crops, with important consequences on the bio and green economy. © 2019 Society of Chemical Industry.


Assuntos
Antioxidantes/análise , Bentonita/análise , Produção Agrícola/métodos , Fertilizantes/análise , Cebolas/química , Extratos Vegetais/análise , Enxofre/análise , Resíduos/análise , Antioxidantes/metabolismo , Bentonita/metabolismo , Olea/química , Cebolas/crescimento & desenvolvimento , Cebolas/metabolismo , Extratos Vegetais/metabolismo , Enxofre/metabolismo
14.
Environ Geochem Health ; 42(1): 95-108, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31011941

RESUMO

Soils formed after the desiccation of Lake Atamanskoe, which has served as a reservoir for liquid industrial waste from the city of Kamensk-Shakhtinsky during a long time, were studied. These soils differ from zonal soils by a strong contamination with zinc and sulfur. Preliminary studies showed that Fe compounds fix a significant part of zinc. This requires to study S, Zn, and Fe minerals. In this work, Mössbauer spectroscopy was used for the identification of iron compounds and scanning electron microscopy was used for the microanalysis of these and other minerals. To facilitate the identification of Fe minerals, brown iron ocher was removed from a contaminated soil sample and analyzed. From electron microscopy and Mössbauer spectroscopy data, ocher contained hydrogoethite with a high content of sorption water and schwertmannite (a rare mineral, probably found in Russia for the first time). The chemical composition of this schwertmannite better corresponds to the Cashion-Murad model than to the Bigham model. Particles of partially oxidized magnetite and wustite enriched with zinc were revealed under electron microscope. Siderite with partial substitution of Fe2+ by Zn2+ was detected. Thus, contaminated hydromorphic soil contains both common minerals (illite, goethite, hematite, gypsum) and rare minerals (schwertmannite, Zn siderite, partially oxidized magnetite and wustite enriched with zinc).


Assuntos
Ferro/análise , Minerais/análise , Poluentes do Solo/análise , Enxofre/análise , Zinco/análise , Carbonatos/análise , Compostos Férricos/análise , Compostos Ferrosos/análise , Compostos de Ferro/análise , Minerais/química , Federação Russa , Solo/química
15.
Crit Rev Anal Chem ; 50(2): 161-178, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31001988

RESUMO

Determination of sulfur and deleterious trace elements in crude oil has long been an area of active investigation and still attracting interest due to their undesirable economic consequences and adverse environmental impacts. Therefore, analytical methods devoted to their sensitive, rapid, and accurate determination are of paramount importance in various areas of oil refining and petrochemical industry. In the present review, occurrence and implications of the main metallic constituents in crude oil are summarized. Furthermore, currently available methodological approaches including sample pretreatment procedures along with the most commonly used measurement techniques employed for crude oil analysis are overviewed. A summary of the applications and recent developments over the past years is discussed. The basic principle, pros and cons of each analytical method are highlighted. The overview is based on 172 references.


Assuntos
Petróleo/análise , Enxofre/análise , Oligoelementos/análise , Análise Espectral
16.
Sci Total Environ ; 699: 134277, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31689668

RESUMO

Oil sands developments release acidifying compounds (SO2 and NO2) with the potential for acidifying deposition and impacts to forest health. This article integrates the findings presented in the Oil Sands Forest Health Special Issue, which reports on the results of 20 years of forest health monitoring, and addresses the key questions asked by WBEA's Forest Health Monitoring (FHM) Program: 1) is there evidence of deposition affecting the environment?, 2) have there been changes in deposition or effects over time?, 3) do acid deposition levels require management intervention?, 4) what are major sources of deposited substances? and 5) how can the program be improved? Deposition of sulphur, nitrogen, base cations (BC), polycyclic aromatic compounds and trace elements decline exponentially with distance from sources. There is little evidence for acidification effects on forest soils or on understory plant communities or tree growth, but there is evidence of nitrogen accumulation in jack pine needles and fertilization effects on understory plant communities. Sulphur, BC and trace metal concentrations in lichens increased between 2008 and 2014. Source apportionment studies suggest fugitive dust in proximity to mining is a primary source of BC, trace element and organic compound deposition, and BC deposition may be neutralizing acidifying deposition. Sulphur accumulation in soils and nitrogen effects on vegetation may indicate early stages of acidification. Deposition estimates for sites close to emissions sources exceed proposed regulatory trigger levels, suggesting a detailed assessment of acidification risk close to the emission sources is warranted. However, there is no evidence of widespread acidification as suggested by recent modeling studies, likely due to high BC deposition. FHM Program evolution should include continued integration with modeling approaches, ongoing collection and assessment of monitoring data and testing for change over time, and addition of monitoring sites to fill gaps in regional coverage.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Florestas , Campos de Petróleo e Gás , Líquens , Modelos Teóricos , Nitrogênio/análise , Compostos Orgânicos , Pinus , Enxofre/análise , Árvores
17.
J Chromatogr A ; 1611: 460605, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31662186

RESUMO

The petroleum industry is increasingly concerned with the conversion of vacuum residues as a consequence of decreased conventional crude oil availability. The compositional analysis of heavy oil products has become a key step in conversion processes, but the complexity of these oil matrices tends to increase with their boiling point. In this study, comprehensive two-dimensional liquid chromatography (LCxLC) coupled to inductively coupled mass spectrometry (ICP-MS/MS) is considered with a view to meet new requirements and to bring additional information regarding the species present in these matrices. In search for a high degree of orthogonality, two separation techniques involving two different retention mechanisms were evaluated: Size Exclusion Chromatography (SEC) and Reverse Phase Liquid Chromatography (RPLC). In SEC, the analytes are separated according to their molecular weight while according to their hydrophobicity in RPLC. The separation power of both individual separation techniques was first evaluated. Off-line and on-line LCxLC were compared on the basis of an optimization approach. It is shown that off-line SECxRPLC can provide, for the same analysis time of 150 min, a higher peak capacity (2600 vs 1700) than on-line RPLCxSEC while a similar dilution factor (close to 30) but also requires far fewer fractions to be analyzed (12 vs 400). Asphaltenes which constitute the heaviest fraction of crude oils (obtained from petroleum industry) were analyzed by the developed off-line SECxRPLC method. The resulting 2D-contour plots show that co-elutions could be removed leading, for the first time, to new information on high molecular weight species containing sulfur and vanadium.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Níquel/análise , Petróleo/análise , Enxofre/análise , Espectrometria de Massas em Tandem/métodos , Vanádio/análise , Cromatografia em Gel , Cromatografia de Fase Reversa , Interações Hidrofóbicas e Hidrofílicas , Poliestirenos/química , Padrões de Referência
18.
Radiat Prot Dosimetry ; 186(2-3): 202-205, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31702764

RESUMO

The unique feature of nuclear accidents with neutron exposure is the induced radioactivity in body tissues. For dosimetry purposes, the most important stable isotopes occurring in human body, which can be activated by neutrons, are 23 Na and 32 S. The respective activation reactions are as follows:23Na(n,γ)24Na and32S(n,p)32P. While sodium occurs in human blood, sulfur is present in human hair. In order to verify the practical feasibility of this dosimetry technique in conditions of our laboratory, samples of human blood and hair were irradiated in a channel of a training reactor VR-1.24Na activity was measured by gamma-ray spectrometry.32P activity in hair was measured by means of a proportional counter. Based on neutron-spectrum calculation, relationships between neutron dose and induced activity were derived for both blood and hair.


Assuntos
Sangue/efeitos da radiação , Cabelo/efeitos da radiação , Nêutrons , Radioisótopos de Fósforo/análise , Radiometria/métodos , Sódio/análise , Enxofre/análise , República Tcheca , Raios gama , Humanos , Doses de Radiação , Liberação Nociva de Radioativos , Radioatividade , Radioisótopos de Sódio
19.
Artigo em Inglês | MEDLINE | ID: mdl-31623089

RESUMO

This study aimed to investigate the characteristics of gaseous emission (methane-CH4, carbon dioxide-CO2, nitrous oxide-N2O, nitric oxide-NO, hydrogen sulfide-H2S and sulfur dioxide-SO2) and the conservation of carbon (C), nitrogen (N), and sulfur (S) during cattle manure composting under different aeration strategies. Three aeration strategies were set as C60, C100, and I60, representing the different combinations of aeration method (continuous-C or intermittent-I) and aeration rate (60 or 100 L·min-1·m-3). Results showed that C, N, S mass was reduced by 48.8-53.1%, 29.8-35.9% and 19.6-21.9%, respectively, after the composing process. Among the three strategies, the intermittent aeration treatment I60 obtained the highest N2O emissions, resulting in the highest N loss and greenhouse gas (GHG) emissions when the GHG emissions from power consumption were not considered. Within two continuous aeration treatments, lower aeration rates in C60 caused lower CO2, N2O, NO, and SO2 emissions but higher CH4 emissions than those from C100. Meanwhile, C and N losses were also lowest in the C60 treatment. H2S emission was not detected because of the more alkaline pH of the compost material. Thus, C60 can be recommended for cattle manure composting because of its nutrient conservation and mitigation of major gas and GHG emissions.


Assuntos
Dióxido de Carbono/análise , Compostagem/métodos , Esterco/análise , Nitrogênio/análise , Enxofre/análise , Aerobiose , Anaerobiose , Animais , Bovinos
20.
J Agric Food Chem ; 67(44): 12313-12321, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31618030

RESUMO

Soybean provides essential protein and amino acids for humans and animals, while sulfur-containing amino acids (SAA), including methionine (Met) and cysteine (Cys), are very limited. In this study, we constructed a high-density bin-map with 3420 bin markers using 676 857 SNPs of a recombinant-inbred line (RIL) population derived from a cross between Kefeng no. 1 and Nannong 1138-2. Quantitative trait loci (QTL) mapping was performed for Cys, Met, SAA, and the protein content using this high-density bin-map. Twenty-five QTLs linked to these four traits were identified, and four genomic regions located on chromosomes (Chr) 07, 08, 15, and 20 were overlapped by multiple QTLs. Among them, bin 115-124 located on Chr 15 was associated with all four traits and was a novel locus with a high LOD value. These findings will provide a basis for nutritional quality improvement using marker-assisted selection breeding and clarify the genetic mechanisms of SAA and protein in soybean.


Assuntos
Aminoácidos/análise , Locos de Características Quantitativas , Proteínas de Soja/genética , Soja/genética , Enxofre/análise , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Polimorfismo de Nucleotídeo Único , Sementes/química , Sementes/genética , Soja/química
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