element concentration
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2022 ◽  
Author(s):  
V.H. Isakson ◽  
et al. ◽  
M.D. Schmitz

<div>Figure S1. Thin-section photomicrographs for lithologies of the Bannock Volcanic Member and Scout Mountain Member of the Pocatello Formation exposed at Scout Mountain, Idaho. Sample numbers are illustrated on the stratigraphic section of Figure 4. Field of view is 24 mm × 40 mm. Tables S1–S3: LA-ICPMS U-Pb isotope and trace element concentration data. Table S4: CA-IDTIMS U-Pb isotope data.<br></div>


2022 ◽  
Author(s):  
V.H. Isakson ◽  
et al. ◽  
M.D. Schmitz

<div>Figure S1. Thin-section photomicrographs for lithologies of the Bannock Volcanic Member and Scout Mountain Member of the Pocatello Formation exposed at Scout Mountain, Idaho. Sample numbers are illustrated on the stratigraphic section of Figure 4. Field of view is 24 mm × 40 mm. Tables S1–S3: LA-ICPMS U-Pb isotope and trace element concentration data. Table S4: CA-IDTIMS U-Pb isotope data.<br></div>


Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 426
Author(s):  
Zhao Yang ◽  
Xiaolong He ◽  
Bin Li ◽  
Andrej Atrens ◽  
Xuyue Yang ◽  
...  

The influence of Si, Cu, B, and trace alloying elements on the conductivity of aluminum die cast 12 (ADC12) alloy was investigated. The conductivity decreased linearly with increasing volume fraction of the Si phase attributed to a linear decrease of the volume of the more conductive Al phase through a rule of mixtures. The conductivity also decreased with increasing Cu content, between 0~3%. The conductivity increased with increasing B content, reached the peak at 0.02% B and thereafter decreased somewhat. The mechanism was that B reacted with the transition element in the Al phase to form boride, decreasing the transition element concentration in the Al lattice, and decreasing the lattice constant. The thermal conductivity, λ, was related to the electrical conductivity, σ, by means of λ=LTσ+λg, where L is the apparent Lorentz constant, 1.86 × 10−8; T is the absolute temperature, 293 K; λg is the lattice conductivity, 42.3 W/(m·K).


2021 ◽  
Author(s):  
Charles Madden ◽  
Jamie K. Pringle ◽  
Adam J. Jeffery ◽  
Kristopher D. Wisniewski ◽  
Vivienne Heaton ◽  
...  

Abstract Human remains have been interred in burial grounds since historic times. Although the re-use of graveyards differs from one country, region or time-period to another, over time graveyard soil may become contaminated or enriched with heavy metal elements. This paper aims to present heavy metal element soil analysis from two UK church graveyard study sites with contrasting necrosols, but similar burial densities and known burial ages dating back to the 16th Century and some possibly older than 1,000 years. Portable X-Ray Fluorescence (pXRF) element analyses were undertaken, both in-situ on surface locations and laboratory-based on surface and near-surface soil pellets. Results show elevated levels of Pb, Mn, Cr, Cu, Zn and Ca in both necrosols when compared to background values. Element concentration anomalies remained consistently higher than background samples down to 2 m bgl, where sampled, but reduced away from church buildings which may reflect burial densities. Element concentration anomalies were higher in the clay-rich necrosol than in sandy necrosol. Field-based rapid measurements gave similar relative concentration values to laboratory-based soil pellet measurements, although laboratory-based analyses were more precise. Study results implications suggest that long-used necrosols are likely to be more contaminated with heavy-metal elements than similar soil outside graveyards with implications for burial grounds management, adjacent populations and where burial grounds have been deconsecrated and turned to residential dwellings.


2021 ◽  
Vol 5 (1) ◽  
pp. 23
Author(s):  
Sofia Barbosa ◽  
António Dias ◽  
Ana Ferraz ◽  
Sandra Amaro ◽  
M. Graça Brito ◽  
...  

The main goal of this study was to identify potential chemical elements present in three types of polymetallic mine waste, stored in the old mine site of São Domingos, located in the Iberian Pyrite Belt, Alentejo, Southern Region of Portugal. This study involves the characterization of potential resources in those mine residues, bearing in mind that its reprocessing can facilitate the environmental remediation and rehabilitation activities which are underway at the site. X-ray Fluorescence (XRF) and micro (μ)-XRF 2D mapping surveys were performed. Univariate and multivariate data analysis reveal that differences in compositions are mainly related with element concentration per type of waste. Image processing and clustering analysis allowed the recognition of distinct elemental spatial distribution patterns. Some of these residues, although classified as archeological-industrial heritage materials may present toxicity to the ecological environment and to human health. This fact enhances, therefore, geoethical doubts regarding its remining and exploitability. In this context, a multi-criteria decision analysis considering two geoethical alternatives was performed.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Devis Montroni ◽  
Andrea Simoni ◽  
Viviana Pasquini ◽  
Enrico Dinelli ◽  
Claudio Ciavatta ◽  
...  

AbstractThe fan shell Pinna nobilis is the largest bivalve endemic to the Mediterranean and is actually a strongly endangered species. Due to the biological, ecological, and historical relevance of this species, the research of a non-lethal method to relate the element content in organism’s tissues and environment can provide information potentially useful to evaluate environmental pollution and organism physiological status. In this study, a screening on element concentration in the animal growing environment (seawater and sediments) and in four soft tissues (hepatopancreas, gills, mantle, and muscle), and two acellular tissues (calcite shell layer, and byssus) was performed. The comparison among these results was used to assess whether the no-lethal acellular tissue element concentration can be used to reveal the element presence in the environment and soft tissues. Elements, such as B, Ag, As, Mn, Mo, Pb, or Se, showed a possible relationship between their presence in the byssus and soft tissues. In the byssus Cr, Sb, Sn, and V have shown to be mostly related to the environment, more than the soft tissues, and might be used to draw a historical record of the exposure of the organism. The element concentration in the calcite shell layer did not relate with environmental element concentrations. Essential elements, like Cu, Fe, Ni, and Zn, were present in calcite shell layer and byssus and are likely related to their biological activity in the organism. The research also gave an overview on the presence of pollution and on the preferential intake route of the element. In summary, this study, performed on a limited number of specimens of this protected species, indicated that element concentration in the byssus can be applied as non-lethal method to monitor this endangered species and its interaction with the elements in the growing environment.


Author(s):  
Fareh Abudawaba ◽  
Eslam Gomaa ◽  
Ahmed Gheni ◽  
Mohamed ElGawady

This study investigated the use of class C fly ash (FA) as a precursor for alkali-activated mortar (AAM) for 3D-printed concrete (3DPC). AAMs with different water-to-FA (W/FA), alkaline activator-to-FA (Alk/FA), and sodium silicate-to-sodium hydroxide (SS/SH) ratios were examined to develop mixtures that can be tailored for different structural applications of 3DPC. The fresh properties, including extrudability and buildability, were evaluated through the open time (OT) and immediate deformation tests, respectively. Different cycle times (CTs) were applied to achieve a strain limit state necessary to maintain the printed shape. The strength of AAMs in different directions at different CTs was examined. Scanning electron microscopy (SEM) was carried out on AAM specimens having different CTs for a better understanding of the bond area. OTs ranging from 2.5 min to 31 min and axial strains ranging from 0.17% to 11.2% were achieved depending on the proportions of the AAMs and CT, which offers flexibility in optimizing the speed of printing and strength of concrete for different projects. The 3DPC specimens displayed anisotropic behavior compared with full-height specimens, where the compressive strength of full-height specimens was higher by 0.2% to 18% and 0.9% to 28% than 3DPC specimens when tested parallel and normal to the printing directions, respectively. SEM images and line scan indicated an approximately even intensity of the element concentration at the interfacial zones of AAMs having short CTs, which explained the relatively high compressive strength of those specimens. For AAMs having long CTs, there was a significant change in the intensity of the element concentration at the interfacial bond zone, and voids were observed resulting in low compressive strength of those specimens.


Author(s):  
Sulieman Ahmed Gasim El Said ◽  
Hatil Hashim EL-Kamali ◽  
Sara Ahmed Saad

Analysis of some selected physico-chemical parameters and macro-elements in soil samples collected from six farmlands (Agricultural schemes) in Khartoum State, Central Sudan : EL-Gomouya, Wad Ramli, Umm Arda, EL-Waha, EL-Silait and EL-Shaab schemes) were carried out The soil characterization was carried out for parameters like pH, organic carbon, moisture content, electrical conductivity , soil texture , potassium, sodium, magnesium, calcium and phosphorus in the soil samples. The physicochemical analysis of soil samples understudy showed different concentrations of various parameters at different farmlands. Correlation analysis was employed to examine the relationship between the various parameters in the soil samples.


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