scholarly journals Elemental Composition of Algae-Based Supplements by Energy Dispersive X-ray Fluorescence

Plants ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2041
Author(s):  
Fernando H. Reboredo ◽  
Walter Junior ◽  
Maria F. Pessoa ◽  
Fernando C. Lidon ◽  
José C. Ramalho ◽  
...  
Keyword(s):  
Public Health ◽  
Elemental Composition ◽  
Great Variability ◽  
Energy Dispersive ◽  
Good Source ◽  
X Ray ◽  
High Daily Dose ◽  
Daily Dose ◽  
Organic Arsenic ◽  
And Control

The aim of this study is to evaluate the elemental composition of fifteen algae-based supplements commonly sold in the Portuguese market, by energy dispersive X-ray fluorescence. Despite the fact that the majority of Kelp samples were a good source of iodine, the levels observed might well contribute to an excess in the human body, which can cause dysfunction of the thyroid gland. Furthermore, the presence of lead in Sea spaghetti, Arame, Hijiki and Wakame caused a considerable risk to public health vis a vis possible ingestion of a high daily dose. Regarding arsenic, great variability was observed in all the samples with concentrations equal to or above 60 μg/g in the case of Arame, KelpJ and Hijiki. Although algae mainly accumulate organic arsenic, some also contain high levels of its inorganic form, as is commonly pointed out for Hijiki. Thus, regular ingestion of these supplements must also take into account the mentioned facts. There is no doubt that these supplements are also good sources of other nutrients, but the lack of accurate regulations and control should alert consumers to avoid indiscriminate use of these types of products.

Field-Emission Scanning Electron Microscopy and Energy-Dispersive X-Ray Analysis to Understand the Role of Tannin-Based Dyes in the Degradation of Historical Wool Textiles

2014 ◽  
Vol 20 (5) ◽  
pp. 1534-1543 ◽  
Author(s):  
Annalaura Restivo ◽  
Ilaria Degano ◽  
Erika Ribechini ◽  
Josefina Pérez-Arantegui ◽  
Maria Perla Colombini
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Elemental Composition ◽  
Field Emission ◽  
Cross Sections ◽  
Morphological Changes ◽  
Energy Dispersive ◽  
X Ray ◽  
Edx Analysis ◽  
Scanning Electron

Abstract:An innovative approach, combining field-emission scanning electron microscopy (FESEM) with energy dispersive X-ray spectroscopy (EDX) analysis, is presented to investigate the degradation mechanisms affecting tannin-dyed wool. In fact, tannin-dyed textiles are more sensitive to degradation then those dyed with other dyestuffs, even in the same conservation conditions.FESEM-EDX was first used to study a set of 48 wool specimens (artificially aged) dyed with several raw materials and mordants, and prepared according to historical dyeing recipes. EDX analysis was performed on the surface of wool threads and on their cross-sections. In addition, in order to validate the model formulated by the analysis of reference materials, several samples collected from historical and archaeological textiles were subjected to FESEM-EDX analysis.FESEM-EDX investigations enabled us to reveal the correlation between elemental composition and morphological changes. In addition, aging processes were clarified by studying changes in the elemental composition of wool from the protective cuticle to the fiber core in cross-sections. Morphological and elemental analysis of wool specimens and of archaeological and historical textiles showed that the presence of tannins increases wool damage, primarily by causing a sulfur decrease and fiber oxidation.

Energy Dispersive X-Ray Spectrometry of Gold-Silver-Copper Standards for Comparison with Historic Gold Objects

1990 ◽  
Vol 185 ◽  
Author(s):  
S.M. White ◽  
R.J. Koestler ◽  
C. Blair ◽  
N. Indictor
Keyword(s):  
Elemental Composition ◽  
Ternary Mixtures ◽  
Energy Dispersive ◽  
X Ray ◽  
Silver Copper ◽  
Gold Silver

AbstractSeven ternary mixtures of gold(80-95%)-silver(4-15%)-copper(1-15%) were prepared as standards for the determination of elemental composition by energy dispersive X-ray spectrometry (EDS). Two geometric forms (flat and oblate) of the standards were prepared for comparison to the analyses of historic gold objects. Surface analyses were performed. Polished sections of the standards were also analysed Comparison between two methods for collecting EDS data is reported. The analyses are discussed in terms of developing a generalized methodology for estimating elemental composition of museum artifacts.

X-ray microanalysis of the cuticle surface of the terrestrial isopod Porcellionides pruinosus

1987 ◽  
Vol 65 (5) ◽  
pp. 1218-1223 ◽  
Author(s):  
Neil F. Hadley ◽  
Gregory M. Hendricks
Keyword(s):  
Acetic Acid ◽  
Elemental Composition ◽  
Marked Reduction ◽  
Common Origin ◽  
Energy Dispersive ◽  
X Ray ◽  
Structural Support ◽  
Terrestrial Isopod

The elemental composition of the cuticle surface and associated microstructures of the isopod Porcellionides pruinosus was examined using energy dispersive X-ray spectroscopy (EDS). The cuticle surface (epicuticle + exocuticle), balls, tricorns, tricorn lips, and epimeral sensilla all contained abundant calcium, with smaller amounts of sulfur, potassium, phosphorus, and chloride also present. Silicon was detected only in the sensilla. The ratios of these lesser elements to calcium were similar in the tricorns, balls, and lips, supporting their common origin. There was a marked reduction in the amount of calcium in the exuviae, and in the amount of calcium and other elements in newly released young when compared with intermoult adult cuticle. Cuticle treated with acetic acid exhibited loss of structural support and no calcium peak in the EDS spectrum, whereas treatment with EDTA had no effect on calcium levels or cuticle morphology.

Aluminium Distribution in Freeze-Dried Roots of Cabbage, Lettuce and Kikuyu Grass by Energy-Dispersive X-Ray Analysis

1980 ◽  
Vol 7 (1) ◽  
pp. 101 ◽  
Author(s):  
DO Huett ◽  
RC Menary
Keyword(s):  
Emission Spectra ◽  
Energy Dispersive ◽  
Poor Correlation ◽  
Cortical Cells ◽  
X Ray ◽  
Freeze Dried ◽  
Back Ground ◽  
The Mean ◽  
Kikuyu Grass ◽  
And Control

The aluminium distribution in transverse sections of fractured and freeze-dried roots of cabbage, lettuce and kikuyu grass was studied by energy-dispersive X-ray analysis. The mean ratios of the integrated counts corresponding to Kα emission spectra for aluminium, phosphorus and silicon were recorded between aluminium and control treatments over three experiments. Peak-to-back- ground ratios (PA/B) were calculated and the aluminium ratios corrected for variations in the corresponding total silicon ratios. Aluminium was found to be uniformly distributed along roots of the three species. The highest peaks (PA) and peak-to-background ratios, suggesting higher concentrations, were recorded in the epidermis followed by the cortex. Aluminium was recorded in the stele of all species and in the protoplasm of cortical cells, with smaller amounts in the protoplasm of xylem parenchyma cells for lettuce and kikuyu grass. The distribution of aluminium supports the hypothesis that its entry to the stele can be achieved by transport both into meristematic cells and the symplasm via the cortex and hence bypassing the barrier at the endodermis. The latter evidence was supported by the presence of aluminium in the radial wall (and cytoplasm) of the endodermis for each species. There was a poor correlation between the distribution of aluminium and phosphorus.

Elemental Composition of the Developing Inner Ear

1981 ◽  
Vol 90 (1) ◽  
pp. 25-32 ◽  
Author(s):  
Matti Anniko ◽  
Romuald Wroblewski
Keyword(s):  
Inner Ear ◽  
Elemental Composition ◽  
Apical Part ◽  
Energy Dispersive ◽  
X Ray ◽  
Peak Intensity ◽  
Relative Peak Intensity ◽  
Present Technique ◽  
Before And After ◽  
Endolymphatic Space

The elemental composition of the inner ear fluid-filled compartments has been analyzed using the x-ray energy dispersive technique (CBA mouse). Special attention has been focused on the maturation of endolymph. A few days before and after birth the relative peak intensity of potassium (R k) in the vestibular endolymphatic compartment was slightly surpassing that in the cochlear part of the labyrinth. From the fourth day after birth (DAB) a rapid increase occurred concerning the R k. The highest R k was found in the endolymphatic space in the basal part of the cochlea followed by that in the vestibular endolymph. The lowest R k was measured in endolymph of the apical part of the cochlea. These obvious differences were abandoned already on the sixth DAB. A mature composition of endolymph was reached on the eighth DAB. The present technique does not allow analyses of differences between cochlear and vestibular endolymph with regard to minimal shifts.

scholarly journals Chemical Analysis of Coal by Energy Dispersive X-Ray Fluorescence Utilizing Artificial Standards

1982 ◽  
Vol 26 ◽  
pp. 457-466
Author(s):  
Bradner D. Wheeler
Keyword(s):  
Chemical Analysis ◽  
Elemental Composition ◽  
Coal Sample ◽  
Energy Dispersive ◽  
Absorption Coefficients ◽  
X Ray ◽  
Geological Materials ◽  
Powder Method ◽  
Mass Absorption ◽  
Calibration Curves

AbstractAccurate determinations of the elemental composition of coal by classical methods can be quite difficult and are normally very time consuming. X-ray fluorescence utilizing the powder method, however, has the ability of providing accurate and rapid analyses. Unfortunately, well characterized standards, although available, are not plentiful. In addition, the durability or stability of ground and pelletized coal samples is poor resulting in deterioration with time. As a result, artificial coal standards were prepared from certified geological materials by fusing in lithium-tetra-borate in percentages approximating expected ash contents and compositions in coal. Since the lithium-tetra-borate comprises about the same percentage of the standard as does the carbon, hydrogen, and oxygen in coal, the ground and pelletized coal sample can be assayed against the fused calibration curves by compensating for the differences in the mass absorption coefficients of the two matrices.

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