scholarly journals Analysis of Corrosion Products Transported through Secondary Side of Candu Steam Generator Using GIXRD

2020 ◽  
Vol 71 (2) ◽  
pp. 99-104
Author(s):  
Alice Dinu ◽  
Mariana Tunaru
Keyword(s):  
Iron Oxide ◽  
Steam Generator ◽  
Corrosion Products ◽  
Feed Water ◽  
X Ray Diffraction ◽  
Blow Down ◽  
X Ray ◽  
Oxide Hydroxide ◽  
Secondary Side ◽  
Millipore Filters

To verify the chemistry of secondary side of CANDU steam generators, Millipore filters are used to sampling from condensing extraction pump, feed water header and blow down of steam generator. These filters retain the corrosion products as very fine particles and are used as samples in chemistry water control. X-Ray diffraction (XRD) is the most used technique that can provide information about the phase composition of analyzed samples. Because the crud layers on the Millipore filters are very thin, to identify the corrosion products Grazing Incidence X-Ray diffraction (GIXRD) technique was used. The following compounds have identified: magnetite (Fe3O4), hematite (Fe2O3), and iron oxide hydroxide (FeOOH). It was observed a brown-reddish background specific to hematite and iron oxide hydroxide, especially for filters extracted from condensing extraction pump. The black colour of crud present on filters extracted from feed water header and blow down of steam generator shows the presence of magnetite.

scholarly journals Direct Production of a Novel Iron-Based Nanocomposite from the Laser Pyrolysis ofFe(CO)5/MMAMixtures: Structural and Sensing Properties

2010 ◽  
Vol 2010 ◽  
pp. 1-12 ◽  
Author(s):  
R. Alexandrescu ◽  
I. Morjan ◽  
A. Tomescu ◽  
C. E. Simion ◽  
M. Scarisoreanu ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Gas Sensors ◽  
High Sensitivity ◽  
X Ray Diffraction ◽  
Direct Production ◽  
X Ray ◽  
Metallic Particles ◽  
Ir Laser ◽  
Iron Iron ◽  
Optimum Working

Iron/iron oxide-based nanocomposites were prepared by IR laser sensitized pyrolysis ofFe(CO)5and methyl methacrylate (MMA) mixtures. The morphology of nanopowder analyzed by TEM indicated that mainly core-shell structures were obtained. X-ray diffraction techniques evidence the cores as formed mainly by iron/iron oxide crystalline phases. A partially degraded (carbonized) polymeric matrix is suggested for the coverage of the metallic particles. The nanocomposite structure at the variation of the laser density and of the MMA flow was studied. The new materials prepared as thick films were tested for their potential for acting as gas sensors. The temporal variation of the electrical resistance in presence ofNO2, CO, andCO2, in dry and humid air was recorded. Preliminary results show that the samples obtained at higher laser power density exhibit rather high sensitivity towardsNO2detection andNO2selectivity relatively to CO andCO2. An optimum working temperature of200°Cwas found.

scholarly journals Discovery of Fe7O9: a new iron oxide with a complex monoclinic structure

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Ryosuke Sinmyo ◽  
Elena Bykova ◽  
Sergey V. Ovsyannikov ◽  
Catherine McCammon ◽  
Ilya Kupenko ◽  
...  
Keyword(s):  
Applied Sciences ◽  
Crystal Structure ◽  
Iron Oxide ◽  
Iron Oxides ◽  
Industrial Applications ◽  
Ambient Conditions ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Pressure High Temperature ◽  
Insight Into

Abstract Iron oxides are fundamentally important compounds for basic and applied sciences as well as in numerous industrial applications. In this work we report the synthesis and investigation of a new binary iron oxide with the hitherto unknown stoichiometry of Fe7O9. This new oxide was synthesized at high-pressure high-temperature (HP-HT) conditions, and its black single crystals were successfully recovered at ambient conditions. By means of single crystal X-ray diffraction we determined that Fe7O9 adopts a monoclinic C2/m lattice with the most distorted crystal structure among the binary iron oxides known to date. The synthesis of Fe7O9 opens a new portal to exotic iron-rich (M,Fe)7O9 oxides with unusual stoichiometry and distorted crystal structures. Moreover, the crystal structure and phase relations of such new iron oxide groups may provide new insight into the cycling of volatiles in the Earth’s interior.

Monoclinic FeO at high pressures

2008 ◽  
Vol 223 (7/2008) ◽  
Author(s):  
Innokenty Kantor ◽  
Alexander Kurnosov ◽  
Catherine McCammon ◽  
Leonid Dubrovinsky
Keyword(s):  
High Pressure ◽  
Iron Oxide ◽  
Single Crystal ◽  
Diffraction Study ◽  
High Pressures ◽  
X Ray Diffraction ◽  
X Ray

AbstractA high-pressure quasi-single crystal X-ray diffraction study of a synthetic iron oxide Fe

scholarly journals Production and characterization of iron-chromium-zinc pigment based ceramic stain colour of red-brown shade

2013 ◽  
Vol 48 (3) ◽  
pp. 213-216 ◽  
Author(s):  
S Parveen ◽  
SA Jahan ◽  
S Ahmed
Keyword(s):  
Zinc Oxide ◽  
Iron Oxide ◽  
Chemical Durability ◽  
X Ray Diffraction ◽  
X Ray ◽  
Exposure Limit ◽  
Substitute Material ◽  
Pure Chromium ◽  
Iron Chromium

Considering the demand of ceramic stain colours in Bangladesh, an attempt has been taken to develop iron-chromium-zinc pigment based ceramic stain colour of red-brown shade which could be used as an import substitute material in the local ceramic industries. The desired shade of red-brown stain was synthesized from an equimolar mixture of pure chromium oxide (Cr2O3), iron oxide (Fe2O3) and zinc oxide (ZnO). The developed stain was characterized by X-ray diffraction (XRD) technique. The characteristic of the stain complied with the chemical durability. Moreover, chromium leaching was below the permissible exposure limit which makes it as a promising ceramic stain to be used in our ceramic industries. DOI: http://dx.doi.org/10.3329/bjsir.v48i3.17334 Bangladesh J. Sci. Ind. Res. 48(3), 213-216, 2013

scholarly journals PHYSICOCHEMICAL STUDY AND QUANTITATIVE ANALYSIS SWARNA MAKSHIKA BHASMA.

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Rajni Bhardwaj ◽  
Smita Johar ◽  
Amit Kapila ◽  
Amandeep Sharma
Keyword(s):  
Particle Size ◽  
Quantitative Analysis ◽  
Iron Oxide ◽  
Major Element ◽  
X Ray Diffraction ◽  
X Ray ◽  
Minor Elements ◽  
Rhombohedral Crystal ◽  
Main Component ◽  
Reddish Brown Color

Swarnamakshika is grouped under Updhatu of Swarna and is composed of Copper, Iron and Sulphur. In this study Swarnamakshika was subjected to Shodhana by Bharjana with Nimbuka swarasa and Shudha Swarnamakshika was given Bhavana with Nimbuka swarasa and subjected to Varahaputa. With ten Varahaputa Bhasma Siddhi Lakshanas were attained swarnamakshika Marana was done by using Nimbuka swarasa until bhasma siddi lakshanas found and it took 10 puta till it attained reddish brown color. The X-ray diffraction analysis showed that d-identified peaks after 10th puta Swarnamakshika bhasma composition is of Iron oxide with rhombohedral crystal system as main component. EDX analysis of Swarna makshika bhasma shows that it contains Iron and Oxygen, as major element and Copper, Sulphur, Carbon, Aluminium, Calcium etc. as minor elements. FESEM study revealed that the particle size of Ashudha and Shudha Swarnamakshika was in the range of 500 nm-3nm. Keywords: Swarnamakshika Bhasma, Nimbuka swarasa, puta

Corrosion Behavior of Q235A Steel under Wet-Dry Cyclic Condition

2012 ◽  
Vol 557-559 ◽  
pp. 139-142
Author(s):  
Jian Guo Liu ◽  
Yan Tao Li ◽  
Bao Rong Hou
Keyword(s):  
Electron Microscopy ◽  
Chloride Concentration ◽  
Corrosion Products ◽  
Drying Process ◽  
X Ray Diffraction ◽  
Cathodic Process ◽  
X Ray ◽  
Reduction Processes ◽  
Cyclic Condition ◽  
Scanning Electron

The corrosion processes and mechanisms of Q235A steel under wet-dry cyclic condition were studied using polarization curve compared with immersion samples, while, the corrosion morphologies and corrosion products of the steel samples were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The cathodic process of wet-dry samples was likely to be controlled not by the oxygen reduction, but rather by the reduction of corrosion products. During the drying process of the wet-dry sample, the electrolyte thickness decreased and chloride concentration increased. Oxygen would be much easier to diffuse into the interface of electrolyte/metal, which improved the cathodic reduction processes. Except for this, the rust itself took part in the reduction processes and hence increased the corrosion rate of the steel samples.

Characterization of iron oxide-based pigments by synchrotron-based micro X-ray diffraction

2008 ◽  
Vol 42 (1-2) ◽  
pp. 57-62 ◽  
Author(s):  
L.K. Herrera ◽  
M. Cotte ◽  
M.C. Jimenez de Haro ◽  
A. Duran ◽  
A. Justo ◽  
...  
Keyword(s):  
Iron Oxide ◽  
X Ray Diffraction ◽  
X Ray
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