Composition minérale des écailles du Catostomus commersoni issu de deux milieux différents: étude par microscopie électronique analytique

1974 ◽  
Vol 31 (1) ◽  
pp. 63-66 ◽  
Author(s):  
R. van Coillie ◽  
A. Rousseau
Keyword(s):  
Electron Microprobe ◽  
Mineral Content ◽  
The Other ◽  
Catostomus Commersoni ◽  
X Ray ◽  
Healthy Environment ◽  
Microscopie Électronique ◽  
Other Substances ◽  
The Difference ◽  
Polluted Waters

The mineral content of scales, metals only, was studied. Fish of the Catostomus commersoni subspecies were used, taken from a healthy environment, (the Manicouagan River) and an environment polluted by, among other substances, various metals (Rivière des Prairies, near Montréal). X-ray microspectrometry was combined with electron microprobe scanning techniques, with subsequent microdensitometric scanning. Scales contained, in addition to the highly predominant calcium, the following: Na, Mg, Al, K, Fe, Cu, Zn, and Ba, as well as some Cr, Mn, Co, Ni, Sr, Ag, Cd, Cs, Hg, and Pb. All metals were between the circuli in the osteoid structures. The latter category of metals, widely known for their toxicity, were more abundant in the scales of the sample from polluted waters, whereas the reverse was true for the other metals, with the exception of Al and Ba, which were found in equal quantities in both samples. If the difference in content of the scales taken from fish of the two different environments is seen in relation with the fact that the toxic metals are more abundant in polluted waters and the fact that there is the possibility that excess metal from the water can replace calcium in the scales, we may infer that the mineral content of scales is related at least in part to that of the surrounding aquatic environment.

Synthesis and Characterization of Hydroxyapatite for Mercury Removal in Polluted Waters

MRS Advances ◽  
2019 ◽  
Vol 4 (64) ◽  
pp. 3569-3577
Author(s):  
Miguel José Álvarez Velásquez ◽  
Valentina Martínez Cortes ◽  
Lina Paola Guarín Alfaro ◽  
Alejandro Figueroa Jaramillo ◽  
Yesmith Santos Panqueva ◽  
...  
Keyword(s):  
Mercury Removal ◽  
Infrared Spectrophotometry ◽  
X Ray Diffraction ◽  
Negative Effects ◽  
X Ray ◽  
The World ◽  
Other Substances ◽  
Main Components ◽  
Polluted Waters

ABSTRACTAccording to the UNEP, mercury pollution is one of the main contamination problems of the world. The UN showed that more than 1,870 tons of this metal are released into the environment annually. This material arrives to water bodies where fish consume it and then reaches humans, producing negative effects on their health. The hydroxyapatite is one of the main components of bones and has proven itself to be useful in the removal of mercury from polluted sources. The aim of this research project is to synthesize and characterize different formulations of this substance and to determine which is the best selective formulation to remove mercury in water. Currently, twenty-one formulations have been produced. The experimental variables examined are the pH, the temperature and the time of calcination. These variables are characterized with Infrared Spectrophotometry (IR), Scanning Electron Microscope (SEM) and X-ray diffraction (XRD). Before calcination the samples contained 70% of hydroxyapatite. This concentration increased in some of them after calcination. The analysis of the results allowed to test the efficiency of these formulations at removing mercury from water. These materials will also be combined, in future stages of the research, with other substances such as activated carbon and organic fibers to improve their performance. The material will be used to coat a filter so that it can become a piping accessory to remove mercury from polluted waters as it is being recirculated.

In Situ X-Ray Stress Measurement in Electrodeposited Cu Foils under Tensile and Fatigue Loading

2007 ◽  
Vol 353-358 ◽  
pp. 2395-2398 ◽  
Author(s):  
Yoshiaki Akiniwa ◽  
Tsuyoshi Suzuki ◽  
K. Tanaka
Keyword(s):  
Plastic Deformation ◽  
Deformation Behavior ◽  
Stress Measurement ◽  
Fatigue Loading ◽  
The Other ◽  
Full Width ◽  
Half Maximum ◽  
X Ray ◽  
The Difference

Monotonic and cyclic loadings were subjected to electrodeposited copper foils (thickness is 8 and 20 μm), and the deformation behavior was observed. In-situ X-ray stress measurement was carried out under monotonic loading. The tensile strength of 8 μm foil was higher than that of 20 μm foil. On the other hand, the elongation of 8 μm foil was smaller. When the plastic deformation occurred, difference between the X-ray stress and the applied stress became large. The difference of 20 μm foil was larger than that of 8 μm foil. Fatigue strength of 8 μm foil was also higher than that of 20 μm foil. The value of the full width at half maximum, FWHM, increased dramatically at the first cycle, and then the value became nearly constant. Just before fracture, the value increased again. The change in FWHM corresponded to the change in the accumulated ratchet strain.

Carbonate enrichment at the margins of a basic dyke, Ardnamurcha

1974 ◽  
Vol 39 (305) ◽  
pp. 514-524 ◽  
Author(s):  
M. K. Wells ◽  
A. C. S. Smith ◽  
J. F. W. Bowles
Keyword(s):  
Mineral Content ◽  
Microprobe Analysis ◽  
The Other ◽  
Transient Effects ◽  
Basic Dyke ◽  
X Ray ◽  
Fine Grained ◽  
Titaniferous Magnetite ◽  
Oxide Phases ◽  
Opaque Minerals

SummaryA gradational increase in concentration of CO2 towards the margins of a very fine-grained basalt dyke has led to the development of a pale marginal facies, enriched in carbonates, particularly siderite. Increases in CO2 from about 3 % in the interior of the dyke to 8 % at the margins are accompanied by decreases in SiO2 and Fe2O3, increases in Al2O3, and less significant changes in the other major components. Cu, Co, and Zn change only slightly, and Cr, Ni, and Li remain constant. Petrographic variation is considerable, even in the superficially homogeneous interior of the dyke, in which it ranges from a type containing a titanaugite (analysed) to one devoid of pyroxene, but containing conspicuous opaque minerals. Microprobe analysis for Fe and Ti shows that these comprise: cotahedral titaniferous magnetite; rodlets, less than 1 µm thick, of rutile partly altered to, or overgrown by, ilmenite; and sub-opaque patches with a very low Ti/Fe ratio. Plagioclase, An55, is the most abundant and constant crystalline phase in the interior of the dyke, but changes to An20 in the marginal facies. Mineral-content of the latter, deduced from optical, chemical, and X-ray data, also includes siderite, serpentine and clay minerals, leucoxene, and apatite. There is no evidence of quartz, sericite, or calcite.Petrographic evidence shows that variations in concentrations of CO2 and H2O affected phase equilibria from the start of magmatic crystallization. Data on the fO2 required for TiO2 and Fe-oxide phases to co-exist at magmatic temperatures indicate that, initially, the concentrations of CO2 and H2O in the interior of the dyke were higher than the values recorded in analyses of the rocks. From this evidence and the field relationships, it is concluded that the intruding magma was rich in volatiles, which diffused towards the dyke margins and, in part, became trapped as the magma congealed, producing a changed marginal assemblage of minerals. The dyke provides a unique glimpse of influences on a basic magma exerted by what S. J. Shand has aptly termed the ‘fugitive constituents’, the transient effects of which are rarely preserved in the rocks.

Assessment of the mineral density and mineral content of the equine third metacarpal and first phalanx bone by dual energy x-ray absorptiometry

2010 ◽  
Vol 58 (3) ◽  
pp. 317-329 ◽  
Author(s):  
Péter Tóth ◽  
Csaba Horváth ◽  
Viktória Ferencz ◽  
Krisztina Nagy ◽  
Noémi Gligor ◽  
...  
Keyword(s):  
Bone Mineral ◽  
Mineral Content ◽  
Dual Energy ◽  
Mineral Density ◽  
X Ray ◽  
Number Of Patients ◽  
Metacarpal Bones ◽  
The Difference ◽  
The Individual ◽  
The Right

In the first part of this methodological study eleven metacarpi of 9 skeletally normal horses were examined from 4 directions by dual energy x-ray absorptiometry (DXA). The differences between the dorsopalmar-palmarodorsal and lateromedial-mediolateral (opposite sites) bone mineral density (BMD) values were found to be nonsignificant. In the second part of the study the precision of the Norland XR-26 densitometer was tested by measuring 34 metacarpal bones and 34 proximal phalanges, each of them three times, from a single direction. The difference between the individual measurements of the first phalanges and of the metacarpal bones originating from the right or the left side of the same horse were not significant, nor did the age or breed have a significant effect on BMD or bone mineral content (BMC). However, both BMD and BMC are greater in the metacarpal bones than in the proximal phalanges and are higher in geldings than in mares or to stallions, while the BMD or BMC values of mares and stallions did not differ from each other significantly. These data point to the necessity of further BMD studies in a higher number of patients.

Mastoid Pneumatization in Otosclerosis

1989 ◽  
Vol 98 (6) ◽  
pp. 451-454 ◽  
Author(s):  
Jacob Sadé ◽  
Susan Kremer ◽  
Anat Shatz ◽  
Irena Levit
Keyword(s):  
Hereditary Disease ◽  
The Other ◽  
Mastoid Pneumatization ◽  
X Ray ◽  
Healthy Control ◽  
The Difference ◽  
Ray Projection ◽  
The One ◽  
The Right

The extent of mastoid pneumatization in 150 otosclerotic ears was compared with that of 150 healthy control ears. The size of mastoid pneumatization was measured by use of the Schüller lateral x-ray projection with the help of computed planimetry. The measurements showed the average pneumatized area in otosclerotic ears to be 17.4 ± 5 cm2, in contrast to 12.9 ± 4 cm2 for the healthy control ears. The difference between the two groups was highly significant (p<.0001). While both groups showed a bell-shaped distribution of the measured pneumatized area, the curve of the otosclerotic ears was shifted significantly to the right. Our findings indicate a link between otosclerosis on the one hand and highly pneumatized mastoids on the other. This link between a hereditary disease and a specific type of pneumatization points to the likelihood that heredity also plays some role in determining the final type of pneumatization.

scholarly journals Bowel preparation in intravenous urography doesn’t have an impact on the quality of urinary tract image

2017 ◽  
Vol 16 (1) ◽  
pp. 107-114
Author(s):  
Yuyun Yueniwati ◽  
Ari Eko Laksono
Keyword(s):  
Urinary Tract ◽  
Adverse Effects ◽  
Bowel Preparation ◽  
Medical Science ◽  
Intravenous Urography ◽  
The Other ◽  
X Ray ◽  
Intestinal Gas ◽  
The Difference

Purpose: The procedure of bowel preparation before intravenous urography (IVU) is still a controversial debate and it varies in each health center. Preparation is believed to reduce residual feces and intestinal gas thus improving the quality of visualization of the urinary tract. On the other hand, many radiology and urology studies did not mention the need for preparation before IVU procedure. Preparation before IVU, especially giving laxative agent, gives many adverse effects to the patient. The purpose of this study was to know the difference in quality visualization of the urinary tract in IVU patients with and without preparation in Saiful Anwar hospital Malang.Materials and Methods: A total of 20 patients participated in this study and they were divided into two groups in which each group consists of 10 patients with and without preparation before IVU. Abdominal x-ray and IVU were performed on all patients. Urinary tract visualization quality assessment was done through two methods of assessing the quality of the image by the European Commission Guidelines and of assessing the residue of feces/ intestinal gas based on Dadkhah’s studies.Results: Results showed the total score of image quality and the residue of feces/intestinal gas was not significantly different in the abdominal plain photo of IVU patients with and without preparation (Mann-Whitney test (p=1.000) and Independent T-test (p=0.5111)).Conclusions: In conclusion, there was no difference in the quality of visualization of the urinary tract in IVU patients with and without preparation in Saiful Anwar hospital Malang.Bangladesh Journal of Medical Science Vol.16(1) 2017 p.107-114

Holistic Mapping in an Electron Microprobe

2001 ◽  
Vol 7 (S2) ◽  
pp. 146-147
Author(s):  
Colin M. MacRae ◽  
N.C. Wilson ◽  
M. Otsuki
Keyword(s):  
Electron Beam ◽  
Electron Microprobe ◽  
Visible Spectrum ◽  
The Other ◽  
Single Frequency ◽  
Small Range ◽  
Solid Target ◽  
X Rays ◽  
X Ray

When an electron beam interacts with a solid target a number of interactions occur which produce electrons, x-rays and light. Typically in an electron microprobe analyser (EPMA) both the electron and x-ray signals are collected for analysis and imaging. However, if the EPMA is equipped with an optical spectrometer then all three signals can be collected. Commonly, the optical or CathodoLuminescence (CL) spectrometer is a monochromator type and can only collect a single frequency or small range of frequencies at a time. Simultaneous collection of the complete visible spectrum is not possible. The collection optics associated with the spectrometer often must be moved into place to start collection, this then obscures the other detectors and prevents simultaneous collection. At CSIRO Minerals an optical spectrometer has been integrated into a JEOL 8900R EPMA and allows simultaneous collect of all light, x-rays and electron signals. This form of mapping, termed Holistic Mapping, has significant advantages over traditional mapping in that it removes the need to have a priori knowledge about what the important frequencies are that will provide the solution to the problem at hand.

Leonite [K2Mg(SO4)2·4H2O], konyaite [Na2Mg(SO4)2·5H2O] and syngenite [K2Ca(SO4)2·H2O] fromTausoare Cave, Rodnei Mts, Romania

2001 ◽  
Vol 65 (1) ◽  
pp. 103-109 ◽  
Author(s):  
B. P. Onac ◽  
W. B. White ◽  
I. Viehmann
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electron Microprobe ◽  
The Other ◽  
Mineral Association ◽  
X Ray ◽  
Dehydration Product ◽  
Cave Environment ◽  
Dining Room ◽  
Scanning Electron

AbstractTausoare Cave is renowned in Romania for its gypsum and mirabilite speleothems. Of interest are the white crystalline speleothems formed on the floor of the ‘Sala de Mese’ (Dining Room) that were previously described as consisting of mirabilite. The samples we collected reveal crystals of two different habits. One shows the characteristic mirabilite fibrous crystals (cotton-like speleothem) while the other formed bladed and short prismatic crystals which comprise the delicate ‘cave flowers’. The mineral association was characterized by means of X-ray analysis, scanning electron microscopy and electron microprobe. Beside thenardite (dehydration product of mirabilite) we also identified three sulphate minerals: leonite [K2Mg(SO4)2·4H2O], syngenite [K2Ca(SO4)2·H2O] and konyaite [Na2Mg(SO4)2·5H2O]. Of these, leonite and konyaite have never been reported in a cave environment. This paper describes the mineralogy of this particular sulphate deposit and offers some viewpoints on the crystallogenesis.

Difference Fourier Analysis of Glucose Embedded and Frozen Hydrated Purple Membrane

1982 ◽  
Vol 40 ◽  
pp. 74-75
Author(s):  
Jules S. Jaffe ◽  
Robert M. Glaeser
Keyword(s):  
Purple Membrane ◽  
Data Set ◽  
High Resolution Data ◽  
X Ray ◽  
X Ray Crystallography ◽  
Fourier Techniques ◽  
Versus Protein ◽  
The Difference ◽  
Difference Fourier ◽  
Ideal Method

Although difference Fourier techniques are standard in X-ray crystallography it has only been very recently that electron crystallographers have been able to take advantage of this method. We have combined a high resolution data set for frozen glucose embedded Purple Membrane (PM) with a data set collected from PM prepared in the frozen hydrated state in order to visualize any differences in structure due to the different methods of preparation. The increased contrast between protein-ice versus protein-glucose may prove to be an advantage of the frozen hydrated technique for visualizing those parts of bacteriorhodopsin that are embedded in glucose. In addition, surface groups of the protein may be disordered in glucose and ordered in the frozen state. The sensitivity of the difference Fourier technique to small changes in structure provides an ideal method for testing this hypothesis.

Antiphase Boundaries in Ordered Ni3FE Crystals

1969 ◽  
Vol 27 ◽  
pp. 62-63
Author(s):  
Y. H. Liu
Keyword(s):  
Domain Size ◽  
Antiphase Domain ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hardening Mechanism ◽  
Superlattice Structure ◽  
Disordered Phase ◽  
Domain Boundaries ◽  
Atomic Scattering ◽  
The Difference

Ordered Ni3Fe crystals possess a LI2 type superlattice similar to the Cu3Au structure. The difference in slip behavior of the superlattice as compared with that of a disordered phase has been well established. Cottrell first postulated that the increase in resistance for slip in the superlattice structure is attributed to the presence of antiphase domain boundaries. Following Cottrell's domain hardening mechanism, numerous workers have proposed other refined models also involving the presence of domain boundaries. Using the anomalous X-ray diffraction technique, Davies and Stoloff have shown that the hardness of the Ni3Fe superlattice varies with the domain size. So far, no direct observation of antiphase domain boundaries in Ni3Fe has been reported. Because the atomic scattering factors of the elements in NijFe are so close, the superlattice reflections are not easily detected. Furthermore, the domain configurations in NioFe are thought to be independent of the crystallographic orientations.

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