scholarly journals MgO Refractory Doped with ZrO2 Nanoparticles: Influence of Cold Isostatic and Uniaxial Pressing and Sintering Temperature in the Physical and Chemical Properties

Metals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1297 ◽  
Author(s):  
Cristian Gómez-Rodríguez ◽  
Daniel Fernández-González ◽  
Linda Viviana García-Quiñonez ◽  
Guadalupe Alan Castillo-Rodríguez ◽  
Josué Amilcar Aguilar-Martínez ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Cold Isostatic Pressing ◽  
Zro2 Nanoparticles ◽  
Furnace Lining ◽  
Physical And Chemical Properties ◽  
X Ray ◽  
Isostatic Pressing ◽  
Physical And Chemical ◽  
The Impact ◽  
And Chemical Properties

The chemical environment and the internal conditions of the furnaces and ladles are extremely aggressive for the refractories, so metallurgical industries demand refractory linings with greater durability and resistance to avoid unforeseen stoppages and to reduce the changes of the furnace lining. Therefore, the current work aims to evaluate the impact of the additions of ZrO2-nanoparticles (1, 3, and 5 wt. %) in magnesia-based bricks. A comparative study of the physical and chemical properties in bricks obtained using two cold pressing techniques (uniaxial and isostatic pressing) and two sintering temperatures (1550 and 1650 °C) was carried out. The microstructure and crystalline phase characteristics obtained after the heat treatments and the slag corrosion test was studied using scanning electron microscopy/electron dispersive X-ray spectroscopy (SEM/EDX) and X-ray diffraction (XRD). The results reveal that the sample with 5 wt. % of ZrO2 nanoparticles (obtained by cold isostatic pressing and sintering at 1650 °C) has the lowest porosity and greatest resistance to penetration of blast furnace slag.

Monitoring of Fluctuations in the Physical and Chemical Properties of a High-Calcium Fly Ash

1987 ◽  
Vol 113 ◽  
Author(s):  
Scott Schlorholtz ◽  
Ken Bergeson ◽  
Turgut Demirel
Keyword(s):  
Fly Ash ◽  
Chemical Properties ◽  
Operating Conditions ◽  
Physical And Chemical Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Morphological Studies ◽  
High Calcium ◽  
Physical And Chemical ◽  
And Chemical Properties

ABSTRACTThe physical and chemical properties of fly ash produced at Ottumwa Generating Station have been monitored since April, 1985. The fly ash is produced from burning a low sulfur, sub-bituminous coal obtained from the Powder River Basin near Gillette, Wyoming. One-hundred and sixty samples of fly ash were obtained during the two year period. All of the samples were subjected to physical testing as specified by ASTM C 311. About one-hundred of the samples were also subjected to a series of tests designed to monitor the self-cementing properties of the fly ash. Many of the fly ash samples were subjected to x-ray diffraction and fluorescence analysis to define the mineralogical and chemical composition of the bulk fly ash as a function of sampling date. Hydration products in selected hardened fly ash pastes, were studied by x-ray diffraction and scanning electron microscopy. The studies indicated that power plant operating conditions influenced the compressive strength of the fly ash paste specimens. Mineralogical and morphological studies of the fly ash pastes indicated that stratlingite formation occurred in the highstrength specimens, while ettringite was the major hydration product evident in the low-strength specimens.

scholarly journals The Interstellar Medium of Dwarf Galaxies

Galaxies ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 11
Author(s):  
Christian Henkel ◽  
Leslie K. Hunt ◽  
Yuri I. Izotov
Keyword(s):  
Interstellar Medium ◽  
Dwarf Galaxies ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Ionized Gas ◽  
Green Pea ◽  
Physical And Chemical ◽  
The Impact ◽  
The Universe ◽  
And Chemical Properties

Dwarf galaxies are by far the most numerous galaxies in the Universe, showing properties that are quite different from those of their larger and more luminous cousins. This review focuses on the physical and chemical properties of the interstellar medium of those dwarfs that are known to host significant amounts of gas and dust. The neutral and ionized gas components and the impact of the dust will be discussed, as well as first indications for the existence of active nuclei in these sources. Cosmological implications are also addressed, considering the primordial helium abundance and the similarity of local Green Pea galaxies with young, sometimes protogalactic sources in the early Universe.

scholarly journals PHYSICAL AND CHEMICAL STUDIES OF OVERROOF ROCKS OF CLAY SHALES OF THE DZHERDANAK DEPOSIT

2021 ◽  
pp. 16-21
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Chemical Properties ◽  
Mineralogical Composition ◽  
Physical And Chemical Properties ◽  
X Ray ◽  
Clay Shales ◽  
Chemical Studies ◽  
Physical And Chemical ◽  
And Chemical Properties

The purpose of this study is study of the physical and chemical properties of the overburden of the Dzherdanak deposit. The chemical and mineralogical composition of the overburden of the Djerdanak deposit has been studied by the methods of X-ray and thermography, electron microscopy and infrared spectroscopy. The main phases are quartz, kaolinite and muscovite. The study of the fine structure of the rock under an electron microscope showed the homogeneity of the rock with pronounced uniform inclusions, which is preserved even after firing. Changes in the rock after firing at 1050 °C have been determined. The formation of mullite at this temperature has been established.

scholarly journals An Overview of Dynamic Heterogeneous Oxidations in the Troposphere

Environments ◽  
2018 ◽  
Vol 5 (9) ◽  
pp. 104 ◽  
Author(s):  
Elizabeth Pillar-Little ◽  
Marcelo Guzman
Keyword(s):  
Atmospheric Aerosols ◽  
Atmospheric Transport ◽  
Cloud Condensation Nuclei ◽  
Complex Mixture ◽  
Organic Aerosols ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Physical And Chemical ◽  
The Impact ◽  
And Chemical Properties

Due to the adverse effect of atmospheric aerosols on public health and their ability to affect climate, extensive research has been undertaken in recent decades to understand their sources and sinks, as well as to study their physical and chemical properties. Atmospheric aerosols are important players in the Earth’s radiative budget, affecting incoming and outgoing solar radiation through absorption and scattering by direct and indirect means. While the cooling properties of pure inorganic aerosols are relatively well understood, the impact of organic aerosols on the radiative budget is unclear. Additionally, organic aerosols are transformed through chemical reactions during atmospheric transport. The resulting complex mixture of organic aerosol has variable physical and chemical properties that contribute further to the uncertainty of these species modifying the radiative budget. Correlations between oxidative processing and increased absorptivity, hygroscopicity, and cloud condensation nuclei activity have been observed, but the mechanisms behind these phenomena have remained unexplored. Herein, we review environmentally relevant heterogeneous mechanisms occurring on interfaces that contribute to the processing of aerosols. Recent laboratory studies exploring processes at the aerosol–air interface are highlighted as capable of generating the complexity observed in the environment. Furthermore, a variety of laboratory methods developed specifically to study these processes under environmentally relevant conditions are introduced. Remarkably, the heterogeneous mechanisms presented might neither be feasible in the gas phase nor in the bulk particle phase of aerosols at the fast rates enabled on interfaces. In conclusion, these surface mechanisms are important to better understand how organic aerosols are transformed in the atmosphere affecting the environment.

scholarly journals Fracture analysis and countermeasures of the grid switch castings

2020 ◽  
Vol 165 ◽  
pp. 06015
Author(s):  
Chao Feng ◽  
Siyuan Yang ◽  
Qiao Li ◽  
Mengbao Zhou ◽  
Songqi Wu ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Fracture Analysis ◽  
Casting Defects ◽  
Physical And Chemical Properties ◽  
Direct Reading ◽  
X Ray ◽  
Detection Technology ◽  
Two Stages ◽  
Physical And Chemical ◽  
And Chemical Properties

Based on the detection technology of direct reading spectrum, metallographic microscope and X-ray, the defects of the grid switch castings were analyzed. The four main forms of casting fracture were summarized as poor physical and chemical properties, material misuse, casting defects and designing defects. In order to strengthen the quality control of the source of the product, it was proposed to carry out targeted network inspection in the two stages of material arrival and infrastructure acceptance.

scholarly journals The kinetic parameters of aerosols formed during combustion of modified wood

2018 ◽  
Vol 251 ◽  
pp. 02023
Author(s):  
Feodor Portnov
Keyword(s):  
Grain Size ◽  
Surface Layer ◽  
Chemical Properties ◽  
Quantitative Composition ◽  
Kinetic Properties ◽  
Physical And Chemical Properties ◽  
Physical And Chemical ◽  
The Impact ◽  
And Chemical Properties ◽  
Modified Wood

The paper studies kinetic properties of aerosols formed in thermal degradation of wood. The impact of modifying agents in wood surface layer on the quantitative composition of smoke aerosol solids was analyzed. For this purpose, grain-size of aerosol solids was analyzed, and the physical and chemical properties of source and modified wood were assessed.

scholarly journals A Convenient Synthesis of Antimony Nanorods using 1,2,4,5-Benzenetetracarboxylic Acid

2019 ◽  
Vol 31 (6) ◽  
pp. 1301-1304
Author(s):  
NTAOTE DAVID SHOOTO
Keyword(s):  
Coordination Polymers ◽  
Chemical Properties ◽  
Carboxyl Groups ◽  
Physical And Chemical Properties ◽  
X Ray ◽  
Ideal Candidate ◽  
Convenient Synthesis ◽  
Physical And Chemical ◽  
Coordination Configuration ◽  
And Chemical Properties

1,2,4,5-Benzenetetracarboxylic acid (H4Btec) is an ideal candidate for the synthesis of new coordination polymers compounds because of its four carboxyl groups bridging moieties with antimony ions having distorted coordination configuration. This work reports a new compound of coordination polymer, namely, [Sb2(C4H4O6)2(Btec)(H2O)]n, [(C4H4O6)2 = tartrate and Btec4− = 1,2,4,5-benzenetetracarboxylic anion] has been synthesized under reflux. The physical and chemical properties of coordination polymers; Sb2(C4H4O6)2(Btec)(H2O) was affirmed by scanning electron microscope, Fourier transform infrared spectroscopy, X-ray powder diffraction, thermogravimetric analyses and photoluminescence spectroscopy.

scholarly journals Crystal structure and chemical constitution of basic beryllium acetate and its homologues

1926 ◽  
Vol 112 (761) ◽  
pp. 441-448 ◽  
Keyword(s):  
Crystal Structure ◽  
Organic Compound ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
X Ray ◽  
Chemical Constitution ◽  
Physical And Chemical ◽  
And Chemical Properties

The physical and chemical properties of basic beryllium acetate, OBe 4 (CH 3 .CO 2 ) 6 , are those of a non-ionised substance having the unitary structure of a typical organic compound, each chemical molecule of which may be regarded as forming one co-ordination complex. The fact that the arrangement of the eleven associating units of which this molecule is composed possesses the geometrical attributes of a tetrahedron has led to a stereochemical conception of the constitution of the compound, which is confirmed by the results of X-ray analysis.

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