Study on the oxidation process of cobalt hydroxide to cobalt oxides at low temperatures

RSC Advances ◽  
2016 ◽  
Vol 6 (83) ◽  
pp. 80059-80064 ◽  
Author(s):  
Zhifang Huang ◽  
Yan Zhao ◽  
Yuehong Song ◽  
Yawen Li ◽  
Gongjuan Wu ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Low Temperatures ◽  
Oxidation Process ◽  
Transformation Process ◽  
Cobalt Hydroxide ◽  
Cobalt Oxides ◽  
Temperature Range

The transformation process of cobalt hydroxide (Co(OH)2) to cobalt oxides (Co3O4/CoOOH) in aqueous solution was studied in the temperature range of 50–90 °C.

KINETICS OF THE OXIDATION OF TITANIUM

1950 ◽  
Vol 28b (2) ◽  
pp. 60-72 ◽  
Author(s):  
L. M. Pidgeon ◽  
W. A. Alexander
Keyword(s):  
Low Temperatures ◽  
Oxidation Process ◽  
Film Formation ◽  
Surface Film ◽  
Diffusion Constant ◽  
Initial Oxidation ◽  
Temperature Range ◽  
Logarithmic Equation ◽  
Kinetics Of ◽  
And Diffusion

The rates of oxidation of titanium powder and sintered bar have been investigated in the temperature range 25° to 550 °C. at pressures of 2 and 20 cm. oxygen maintained constant throughout each experiment. It has been shown that the oxidation process can be divided into two mechanisms, viz., the formation of a thin surface film and diffusion of oxide into the metal. The surface film formation at low temperatures follows the logarithmic equation:[Formula: see text]on vacuum annealed metal surface. The diffusion process at higher temperatures is described by the equation:[Formula: see text]after the initial oxidation. This equation leads to preliminary values of the diffusion constant of the order of 10 × 10−8 cm2. per min. in the temperature range 463° to 565 °C.

Features of radiothermoluminescence of polypropylene and ethylene propylenediene elastomer SKEPT-4044 compositions with nanoscale metal-containing fillers

2020 ◽  
pp. 66-73
Author(s):  
A.M. Magerramov ◽  
◽  
N.I. Kurbanova ◽  
M.N. Bayramov ◽  
N.A. Alimirzoyeva ◽  
...  
Keyword(s):  
Transition Temperature ◽  
Molecular Mobility ◽  
Fe3o4 Nanoparticles ◽  
Low Temperatures ◽  
Frost Resistance ◽  
Relaxation Processes ◽  
Ethylene Propylene ◽  
Temperature Range ◽  
Β Relaxation

Using radiothermoluminescence (RTL), the molecular mobility features in the temperature range of 77-300 K were studied for the polypropylene (PP)/ethylene propylene diene elastomer SKEPT-4044 with NiO, Cu2O and Fe3O4 nanoparticles (NPs) based on ABS-acrylonitrile butadiene or SCS-divinyl styrene matrices. It has been shown that the introduction of nanofillers in PP significantly affects the nature and temperature of γ- and β-relaxation processes, while the region of manifestation of the β-process noticeably shifts to the region of low temperatures. Composites with Cu2O NPs have a higher β-transition temperature Tβ than composites with other NPs. It was found that PP/SKEPT-4044 composites with Cu2O NPs with a dispersion of 11-15 nm and acrylonitrile butadiene thermoplastics have optimal frost resistance compared to other compositions.

Photo-degradation of monoazo dye blue 13 using advanced oxidation process

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Aqueous Solution ◽  
Advanced Oxidation Process ◽  
Oxidation Process ◽  
High Energy ◽  
Uv Exposure ◽  
H2o2 Concentration ◽  
Oxidizing Agent ◽  
Photo Degradation ◽  
High Energy Radiation ◽  
Uv Lamp

The high energy radiation overcome the bonding of solute in a solution and H2O2 acts as an oxidizing agent and generates a free radical in the solution which results in photo-degradation by converting the solute in to simple form and resultantly, colored substance under the effect of photo-degradation becomes colorless. The photo-degradation of monoazo dye Blue 13 in an aqueous solution was investigated using a laboratory scale UV lamp in the presence of H2O2 and for maximum degradation of dye, the independent parameter UV power, UV exposure time, pH and H2O2 concentration were optimized. It was found that neither UV in the presence of H2O2 is able to degrade Blue 13 under optimum condition. The results revealed that the use of both UV and H2O2 have pronounced effect on the discoloration of dyes which could be used for management of textile effluents contain waste dyes.

Dynamic Viscosity of Compressed Water to 10 Kilobar and Steam to 1500°C

1969 ◽  
Vol 11 (2) ◽  
pp. 189-205 ◽  
Author(s):  
E. A. Bruges ◽  
M. R. Gibson
Keyword(s):  
Gaseous Phase ◽  
Dynamic Viscosity ◽  
Low Temperatures ◽  
Pressure Range ◽  
Low Pressure ◽  
Temperature Range ◽  
Inversion Temperature ◽  
Pressure Steam ◽  
Correlating Equations ◽  
First Time

Equations specifying the dynamic viscosity of compressed water and steam are presented. In the temperature range 0-100cC the location of the inversion locus (mu) is defined for the first time with some precision. The low pressure steam results are re-correlated and a higher inversion temperature is indicated than that previously accepted. From 100 to 600°C values of viscosity are derived up to 3·5 kilobar and between 600 and 1500°C up to 1 kilobar. All the original observations in the gaseous phase have been corrected to a consistent set of densities and deviation plots for all the new correlations are given. Although the equations give values within the tolerances of the International Skeleton Table it is clear that the range and tolerances of the latter could with some advantage be revised to give twice the existing temperature range and over 10 times the existing pressure range at low temperatures. A list of the observations used and their deviations from the correlating equations is available as a separate publication.

The decomposition mechanism for TDO in aqueous solution within 25–95 °C temperature range

2019 ◽  
Vol 731 ◽  
pp. 136603
Author(s):  
Jianzhong Shao ◽  
Xiaoyun Liu ◽  
Sergei V. Makarov ◽  
Kemei Pei
Keyword(s):  
Aqueous Solution ◽  
Decomposition Mechanism ◽  
Temperature Range

Optimization of Sample Holder Materials for Sensitive Magnetometry Measurements at Low Temperatures

2004 ◽  
Vol 825 ◽  
Author(s):  
I. Bossi ◽  
N.R. Dilley ◽  
J. R. O'Brien ◽  
S. Spagna
Keyword(s):  
Magnetic Field ◽  
Low Temperatures ◽  
Magnetic Response ◽  
Sample Holder ◽  
Magnetization Measurements ◽  
Temperature Range ◽  
Paramagnetic Impurities ◽  
Fused Quartz

AbstractMagnetization measurements were performed as a function of magnetic field H and temperature T on samples of nine different materials including clear fused quartz, cartridge brass, G-10 glass-reinforced epoxy, acetal homopolymer, glass-filled acetal, phenolic, and other plastics. A small yet distinct amount of ferromagnetic or paramagnetic impurities is observed in all the materials investigated in this study except quartz. In contrast, the magnetic response of quartz is typical of a diamagnet over the temperature range 5 K to 300 K. The volume susceptibility is equal to −4.4×10−7 (cgs) over the whole temperature range.

scholarly journals The behaviour of visual purple at low temperature

1941 ◽  
Vol 179 (977) ◽  
pp. 151-159 ◽  
Keyword(s):  
Aqueous Solution ◽  
Low Temperature ◽  
Low Temperatures ◽  
Room Temperature ◽  
Absorption Curve ◽  
Quantum Yields

Visual purple is soluble and stable in a mixture of glycerol and water (3:1). At room temperature the spectrum of such a solution is identical with that of the aqueous solution. At — 73° C the peak of the absorption curve is higher and narrower than at room temperature, and it is shifted towards longer waves. The product of photodecomposition at — 73° C has a spectrum in ­ dependent of pH and is at low temperatures thermostable and photostable, but at room temperature it decomposes therm ally to indicator yellow. The primary product appears to be identical with transient orange. The quantum yields of the photoreaction at low and at room temperature are of the same order.

Electrochemical studies of the Pb2+/Pb(Hg) system in aqueous and aqueous ethylene glycol solutions

1979 ◽  
Vol 57 (14) ◽  
pp. 1801-1803 ◽  
Author(s):  
Tibor Rabockai
Keyword(s):  
Aqueous Solution ◽  
Ethylene Glycol ◽  
Organic Solvent ◽  
Electrochemical Behavior ◽  
Experimental Error ◽  
Electrochemical Studies ◽  
Temperature Range ◽  
All Solutions ◽  
Aqueous Ethylene Glycol ◽  
Current Reversal

The electrochemical behavior of the Pb2+/Pb(Hg) system in aqueous and aqueous ethylene glycol solutions is studied in the temperature range of 20.0 to 50.0 °C by means of current reversal chronopotentiometry. It is shown that the reduction of Pb2+ ion is reversible and that kinetic or catalytic complications are not present. The value of dE1/2/dT is −0.6 mV/deg in the aqueous solution and −0.5 mV/deg in the solution with 56% (w/w) or higher concentrations of the organic solvent. In the above concentration range of ethylene glycol the activation energies of diffusion and viscosity vary from 4.3 × 103 to 7.2 × 103 cal mol−1 and from 3.7 × 103 to 6.7 × 103 cal mol−1, respectively. For all solutions the solvodynamic mean radius of the diffusing species remains constant within the experimental error, suggesting that the diffusing species is always the hydrated Pb2+ ion.

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