heavy elements
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Author(s):  
H. Ernandes ◽  
B. Barbuy ◽  
B. Castilho ◽  
C. J. Evans ◽  
G. Cescutti
Keyword(s):  

Author(s):  
Beatrice Daniela TUDOR ◽  
Bianca Teodora BUCEVSCHI

The paper presents an analysis of the soil in an agricultural area, to determine the influence of pesticides on the soil where agricultural production is carried out. For the research of the soil quality, were analysed areas, for harvesting soil samples. On the samples collected were determined, the amount of nitrates and nitrites from the soil, were determination of heavy elements from soil composition, soil pH and it was observed of the impact of pollutants on the soil.


2021 ◽  
pp. 47-75
Author(s):  
Raymond T. Pierrehumbert

‘What are planets made of?’ assesses what planets are made of, beginning by looking at the life cycle of stars, and the kinds of stars which populate the Universe. Although the first stars of the Universe could not have formed planetary systems, the process did not take long to get under way. The Milky Way galaxy formed not long after the Big Bang and has been building its stock of heavy elements ever since. Thus, our Solar System incorporates ingredients from a mix of myriad expired stars, most of which have been processed multiple times through short-lived stars.


2021 ◽  
Author(s):  
Liping Liu ◽  
Jin Cao ◽  
Wei Guo ◽  
Chongyu Wang

Abstract Heavy elements (X = Ta/W/Re) play an important role in the performance of superalloys, which enhance the strength, anti-oxidation, creep resistance, and anti-corrosiveness of alloy materials in a high-temperature environment. In the present research, the heavy element doping effects in FCC-Ni (γ) and Ni3Al (γ') systems are investigated in terms of their thermodynamic and mechanical properties, as well as electronic structures. The lattice constant, bulk modulus, elastic constant, and dopant formation energy in non-spin, spin polarized, and spin-orbit coupling (SOC) calculations are compared. The results show that the SOC effects are important in accurate electronic structure calculations for alloys with heavy elements. We find that including spin for both γ and γ' phases is necessary and sufficient for most cases, but the dopant formation energy is sensitive to different spin effects, for instance, in the absence of SOC, even spin-polarized calculations give 1% to 9% variance in the dopant formation energy in our model. Electronic structures calculations indicate that spin polarization causes a split in the metal d states, and SOC introduces a variance in the spin-up and spin-down states of the d states of heavy metals and reduces the magnetic moment of the system.


2021 ◽  
Vol 19 (51) ◽  
pp. 7-14
Author(s):  
Hala A Rasheed ◽  
Auday H. Shaban

Groundwater can be assessed by studying water wells. This study was conducted in Al-Wafa District, Anbar Governorate, Iraq. The water samples were collected from 24 different wells in the study area, in January 2021. A laboratory examination of the samples was conducted. Geographical information systems technique was relied on to determine the values of polluting elements in the wells. The chemical elements that were measured were [cadmium, lead, cobalt and chromium]. The output of this research were planned to be spatial maps that show the distribution of the elements with respect to their concentrations. The results show a variation in the heavy elements concentrations at the studied area groundwater. The samples show different values of concentrations; for Cadmium (0.218-1.624) ppm, Lead (0.217-1.157) ppm, Cobalt (0.014-0156) ppm, and for Chromium (0.045-0263) ppm. The distribution of the materials concentrations differs for each element which is refer to the sources of pollution are not relate to industry, but it could be relate to fertilization.


PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0260418
Author(s):  
Somayeh Soltani-Gerdefaramarzi ◽  
Mohsen Ghasemi ◽  
Behzad Ghanbarian

Urban soil pollution with heavy metals is one of the environmental problems in recent years, especially in industrial cities. The aim of this study is to evaluate the role of geogenic and anthropogenic sources in the urban soil pollution in Yazd, Iran. For this purpose, 30 top-soil (0–10 cm) samples from Yazd within an area of 136.37 Km2 and population of nearly 656 thousand are collected, and the concentration of heavy elements is measured. To evaluate factors affecting the concentration of heavy elements in urban soils and determine their possible sources, Multivariate statistical analysis, including correlation coefficient, principal components analysis (PCA) and cluster analysis (CA) are performed. Enrichment Factor (EF), Geo-accumulation index (Igeo), and Modified potential ecological Risk Index (MRI) are used to assess the level and extension of contamination. Results of this study suggest that As, Cd, Pb and Zn are affected by anthropogenic source, while the concentrations of Fe, Mn, Ni, Cr, Co, Cu and Cs have come from mostly natural geologic sources. As, Cd and Pb are considerably enriched in the area, provided moderately enriched for the elements Mn, Zn and Cu. However, the other heavy elements show minimal enrichment. Igeo reveal that Co, Cr, Cs, Cu, Fe, Mn, Zn and Ni with negative values are unpolluted, Pb posed unpolluted to moderately polluted, and As and Cd represent high polluted. Based on the results of the ecological risk factor, the heavy metals of Mn, Ni, Cr, Zn and Cu have a low ecological risk level. More specifically, we find that Pb shows a moderated ecological risk in 39% of the urban soil in the studied area. As and Cd with respectively 100 and 72% contribution have considerable and very high ecological risk. According to the results of MRI, the area is in a very high ecological risk level, and appropriate management practice is essential to reduce the pollution of heavy elements in this area.


Heliyon ◽  
2021 ◽  
pp. e08427
Author(s):  
Michael Lintner ◽  
Bianca Lintner ◽  
Wolfgang Wanek ◽  
Nina Keul ◽  
Frank von der Kammer ◽  
...  

2021 ◽  
Vol 904 (1) ◽  
pp. 012057
Author(s):  
B A AI-Qasi ◽  
M M Sharqi ◽  
S E Faiath

Abstract The study was conducted in the Department of biology - College of Education for Girls - University of Anbar in order to study the effect of cadmium and lead pollution and nitrogen fertilizer sources on the accumulation of heavy metals in the root, the vegetative part, yield and its components of barley (Hordeum vulgare L.) during growing season 2020-2021, Where the experiment was carried out in pots containing 20 kg of soil. The experiment was designed according to a randomized complete block design and in the order of factorial experiments with three replications. The experiment included two factors, the first factor is three concentrations of the elements lead and cadmium (0, 40, 80 mg liter -1), and the second factor is three types of nitrogen fertilizer sources are (ammonium sulfate (NH4)2SO4, ammonium nitrate NH4NO3 and urea CO(NH2)2). The experiment was planted and irrigated with the three nitrogen fertilizer sources on 1/11/2020. After 14 days of planting, heavy metals were added to the soil in the above-mentioned concentrations in the form of two batches. The weight of 1000 grains/g and the concentration of heavy elements (Pb, Cd) in the root, vegetative and grains after harvest were calculated. The results of the study showed: The barley plant had the ability to accumulate heavy elements in the different parts of the plant, and their concentration in the root system was the highest, then the vegetative system, then the grain. However, the accumulated amounts of lead were less than cadmium in the roots, as the highest concentrations of lead and cadmium in the roots were (24.78 and 37.22 mg kg-1) and (61.13 and 92.3 mg kg-1). for the concentrations (40 and 80 mg L-1) respectively.


2021 ◽  
Author(s):  
motahareh esfandiari ◽  
Mohammad Ali Hakimzadeh

Abstract There is a lack of information about urban transport activity in adding heavy elements to the environment. This research assesses concentration some of heavy elements in the deposited atmospheric dust in Yazd bus terminals. Dust samples were collected from the green space in the bus terminals of urban transportation. Following the digestion by nitric acid, determination of the total metal concentration of cadmium(Cd), cobalt(Co), copper(Cu), nickel(Ni), lead(Pb), zinc(Zn), chromium (Cr), and manganese(Mn) in the dust were performed via Atomic Absorption Spectrometry. The map representing the spatial distribution of metals was plotted and their source was identified using Pearson correlation coefficients, Principal Component Analysis(PCA), and Cluster Analysis(CA). The findings indicated that the mean concentration of heavy metals in the deposited dust on the leaves of the trees was in the following order; Cd < Co < Ni < Pb < Cu < Zn < Cr < Mn. The map representing the spatial distribution of heavy metal concentrations indicated that the abundance of metals in different stations varies according to their location. Two important sources for the concentration of heavy metals in the deposited dust on the leaves were identified. The sources of Co, Cd, Mn, and Ni were anthropogenic and lithogenic, and the sources of Pb, Zn, Cr and Cu were the traffic and industrial activities. The amounts of EF, CF, IPI and, RI Indicators in residential, commercial, green space and environmental uses were estimated at low to extremely high levels of pollution. The findings showed that the growth of industrialization and human activities had caused contamination of the environment by heavy metals emitted into the atmosphere of Yazd.


2021 ◽  
pp. 110006
Author(s):  
Yoshitaka Kasamatsu ◽  
Masahiro Nagase ◽  
Hidemi Ninomiya ◽  
Eisuke Watanabe ◽  
Yudai Shigekawa ◽  
...  

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