scholarly journals Characterization of steel billet scales generated during the continuous casting process in SIDERPERU steel plant

2021 ◽  
Vol 242 (1) ◽  
Author(s):  
L. E. Borja-Castro ◽  
A. Bustamante Dominguez ◽  
M. I. Valerio-Cuadros ◽  
R. A. Valencia-Bedregal ◽  
H. A. Cabrera-Tinoco ◽  
...  

AbstractTons of waste is produced during iron steel’s industrial production, creating environmental pollution. This work aims to characterize the steel scale formed on the billet surface during the last step of steel production in the SIDERPERU steel plant. Scanning Electron Microscopy (SEM) shows stacked layers one above the other on steel billets scales surface. Energy Dispersive X-ray (EDX) and X-ray Fluorescence (XRF) reveal the high content of Fe and O, with Ca, Si, Mn, and Cr as minority elemental compounds. X-ray Diffraction (XRD) shows FeO, α-Fe2O3 and Fe3O4 as crystallographic phases. Magnetometry reveals Verwey transition and paramagnetic signals that screen the Morin transition. Mössbauer Spectroscopy at room temperature displays magnetic and non-magnetic parts. The non-magnetic part has the hyperfine parameters corresponding to predominant nonstoichiometric wustite. Octahedral (Fe+2/Fe3+) and tetrahedral Fe+3 hyperfine fields of 46.0 and 49.4 T values respectively are associated to nonstoichiometric magnetite and another sextet with a hyperfine field of 52.0 T is related to hematite.

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3502
Author(s):  
Fangzhou Song ◽  
Masayoshi Uematsu ◽  
Takeshi Yabutsuka ◽  
Takeshi Yao ◽  
Shigeomi Takai

LATP-based composite electrolytes were prepared by sintering the mixtures of LATP precursor and La2O3 nano-powder. Powder X-ray diffraction and scanning electron microscopy suggest that La2O3 can react with LATP during sintering to form fine LaPO4 particles that are dispersed in the LATP matrix. The room temperature conductivity initially increases with La2O3 nano-powder addition showing the maximum of 0.69 mS∙cm−1 at 6 wt.%, above which, conductivity decreases with the introduction of La2O3. The activation energy of conductivity is not largely varied with the La2O3 content, suggesting that the conduction mechanism is essentially preserved despite LaPO4 dispersion. In comparison with the previously reported LATP-LLTO system, although some unidentified impurity slightly reduces the conductivity maximum, the fine dispersion of LaPO4 particles can be achieved in the LATP–La2O3 system.


2000 ◽  
Vol 5 (S1) ◽  
pp. 412-424
Author(s):  
Jung Han ◽  
Jeffrey J. Figiel ◽  
Gary A. Petersen ◽  
Samuel M. Myers ◽  
Mary H. Crawford ◽  
...  

We report the growth and characterization of quaternary AlGaInN. A combination of photoluminescence (PL), high-resolution x-ray diffraction (XRD), and Rutherford backscattering spectrometry (RBS) characterizations enables us to explore the contours of constant- PL peak energy and lattice parameter as functions of the quaternary compositions. The observation of room temperature PL emission at 351nm (with 20% Al and 5% In) renders initial evidence that the quaternary could be used to provide confinement for GaInN (and possibly GaN). AlGaInN/GaInN MQW heterostructures have been grown; both XRD and PL measurements suggest the possibility of incorporating this quaternary into optoelectronic devices.


Inorganics ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 28
Author(s):  
Kriti Pathak ◽  
Chandan Nandi ◽  
Jean-François Halet ◽  
Sundargopal Ghosh

Synthesis, isolation, and structural characterization of unique metal rich diamagnetic cobaltaborane clusters are reported. They were obtained from reactions of monoborane as well as modified borohydride reagents with cobalt sources. For example, the reaction of [Cp*CoCl]2 with [LiBH4·THF] and subsequent photolysis with excess [BH3·THF] (THF = tetrahydrofuran) at room temperature afforded the 11-vertex tricobaltaborane nido-[(Cp*Co)3B8H10] (1, Cp* = η5-C5Me5). The reaction of Li[BH2S3] with the dicobaltaoctaborane(12) [(Cp*Co)2B6H10] yielded the 10-vertex nido-2,4-[(Cp*Co)2B8H12] cluster (2), extending the library of dicobaltadecaborane(14) analogues. Although cluster 1 adopts a classical 11-vertex-nido-geometry with one cobalt center and four boron atoms forming the open pentagonal face, it disobeys the Polyhedral Skeletal Electron Pair Theory (PSEPT). Compound 2 adopts a perfectly symmetrical 10-vertex-nido framework with a plane of symmetry bisecting the basal boron plane resulting in two {CoB3} units bridged at the base by two boron atoms and possesses the expected electron count. Both compounds were characterized in solution by multinuclear NMR and IR spectroscopies and by mass spectrometry. Single-crystal X-ray diffraction analyses confirmed the structures of the compounds. Additionally, density functional theory (DFT) calculations were performed in order to study and interpret the nature of bonding and electronic structures of these complexes.


2014 ◽  
Vol 625 ◽  
pp. 661-664
Author(s):  
Chen Chuang Lok ◽  
Yin Fong Yeong

In the present work, ZIF-8/6FDA-durene mixed matrix membranes (MMMs) were synthesized and characterized. ZIF-8 nanocrystals, which were used as the inorganic filler, were synthesized using rapid room-temperature synthesis method whereas 6FDA-durene polyimide was synthesized by polycondensation method followed by chemical imidization. Pure and 6FDA-durene membranes loaded with 5 wt%, 10 wt% and 15 wt% of ZIF-8 were fabricated. The structural properties and morphology of the resultant membranes were characterized by using X-ray Diffraction (XRD) and Field emission scanning electron microscope (FESEM) . The EDX images showed that ZIF-8 particles agglomerated in the polymer matrix. However, no phase separation was observed for all resultant MMMs.


2009 ◽  
Vol 63 (6) ◽  
Author(s):  
Yan Li ◽  
Chuan-Sheng Liu ◽  
Yun-Ling Zou

AbstractZnO nano-tubes (ZNTs) have been successfully synthesized via a simple hydrothermal-etching method, and characterized by X-ray diffraction, field emission scanning electron microscopy and room temperature photoluminescence measurement. The as-synthesized ZNTs have a diameter of 500 nm, wall thickness of 20–30 nm, and length of 5 µm. Intensity of the plane (0002) diffraction peak, compared with that of plane (10$$ \bar 1 $$0) of ZNTs, is obviously lower than that of ZnO nano-rods. This phenomenon can be caused by the smaller cross section of plane (0002) of the nano-tubes compared with that of other morphologies. On basis of the morphological analysis, the formation process of nano-tubes can be proposed in two stages: hydrothermal growth and reaction etching process.


2017 ◽  
Vol 31 (02) ◽  
pp. 1750006 ◽  
Author(s):  
Mohammad Hossein Ghorbani ◽  
Abdol Mahmood Davarpanah

Manganese oxides are of more interest to researchers because of their ability as catalysts and lithium batteries. In this research, MnO2nanowires with diameter about 45 nm were synthesized by sol–gel method at room temperature (RT). Effect of increasing the annealing temperature from 400[Formula: see text]C to 600[Formula: see text]C on crystalline structure of nanostructure were studied and average crystallite size was estimated about 22 nm. X-ray Diffraction (XRD) method, Energy-Dispersive X-ray Diffraction (EDXD), Scanning Electron Microscopy (SEM) and Vibrating Sample Magnetometer (VSM) were used to characterize the nanowires of MnO2.


1999 ◽  
Vol 595 ◽  
Author(s):  
Jung Han ◽  
Jeffrey J. Figiel ◽  
Gary A. Petersen ◽  
Samuel M. Myers ◽  
Mary H. Crawford ◽  
...  

AbstractWe report the growth and characterization of quaternary AlGaInN. A combination of photoluminescence (PL), high-resolution x-ray diffraction (XRD), and Rutherford backscattering spectrometry (RBS) characterizations enables us to explore the contours of constant- PL peak energy and lattice parameter as functions of the quaternary compositions. The observation of room temperature PL emission at 351nm (with 20% Al and 5% In) renders initial evidence that the quaternary could be used to provide confinement for GaInN (and possibly GaN). AlGaInN/GaInN MQW heterostructures have been grown; both XRD and PL measurements suggest the possibility of incorporating this quaternary into optoelectronic devices.


2020 ◽  
Vol 307 ◽  
pp. 339-344
Author(s):  
Ishak Qayyum Afiqah ◽  
Nik Aziz Nik Ali ◽  
Abd Majid Siti Nurhaziqah ◽  
Hasiah Salleh

Age of monstrous amount of underutilized marine processing byproducts has been perceived as waste and many effort were given to utilize these materials in various application. With an incredible number of study on these byproducts, some compound were identified and apply for human utilization. Hydroxyapatite (HAp) is the main inorganic calcium phosphate mineral with excellent osteoconductivity, good bioactivity and biocompatibility. The production of HAp powder from synthetic process involves many chemicals with complicated procedures. Due to this matter, the raw HAp powder was extracted from natural sources selayang fish bones. Extortion process started with boiling fish bones to eliminate adherent fish meats. After calcination process fish bone were dried in room temperature before crushed by using grinder to obtain the powder. Next, the powder undergo calcination process at 900°C for 5 hours. The characterization of raw HAp was done via X-ray Diffraction, Fourier Transform Infrared Spectometer, Scanning Electron Microscopy, and Thermogravimetric analysis.


2011 ◽  
Vol 10 (01n02) ◽  
pp. 237-240 ◽  
Author(s):  
J. P. BORAH ◽  
C. BORGOHAIN ◽  
K. C. SARMA ◽  
K. K. SENAPATI ◽  
P. PHUKAN

The synthesis of composite magnetic nanomaterials has received increasing attention due to their electronic, magnetic, catalytic, and chemical or biological sensing properties. We have prepared cobalt ferrite–zinc sulfide nanocomposites by a chemical route. The synthesized nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), and photoluminescence spectrometer (PL). The fluorescent magnetic nanoparticles (FMNPs) had a typical diameter of 30±5 nm and saturation magnetization of 5.8 emu g-1 at room temperature. So, these FMNPs may be potentially applied in different fields such as optoelectronic devices, biolabeling, imaging, drug targeting, bioseparation, magnetic fluid hyperthermia, etc.


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