Sort by:
Publication Type:
Open access:
Publication Date:
Periodicals:
Search results
Online since: September 2007
Authors: D. Djurović, Fritz Aldinger, Matvei Zinkevich, Snezana Bošković, V. Srot
On the
basis of shrinkage kinetics data in oxygen atmosphere a master sintering curve for CeO2 was
constructed.
The agreement between the experimental data and the predicted curve is evident.
The experimental data for isothermal sintering at 1020 °C in air were also compared with the predicted densification results (Fig. 8). 0 40 80 120 160 200 240 280 0.70 0.75 0.80 0.85 0.90 0.95 1.00 Experimental data Predicted curve for Ea=285 kJ/mol Relative Density t (min) 0 100 200 300 400 500 600 700 800 0.70 0.75 0.80 0.85 0.90 0.95 1.00 Experimental data Predicted curve for Ea=285 kJ/mol Predicted curve for Ea=500 kJ/mol Relative Density t (min) Fig. 7 Comparison of the predicted densification results with the experimental data for isothermal sintering of ceria at 1200 °C in oxygen atmosphere.
Fig. 8 Comparison of the predicted densification results with the experimental data for isothermal sintering of ceria at 1020 °C in air atmosphere.
These experimental data can be fitted by MSC constructed for apparent activation energy of 500 kJ/mol.
The agreement between the experimental data and the predicted curve is evident.
The experimental data for isothermal sintering at 1020 °C in air were also compared with the predicted densification results (Fig. 8). 0 40 80 120 160 200 240 280 0.70 0.75 0.80 0.85 0.90 0.95 1.00 Experimental data Predicted curve for Ea=285 kJ/mol Relative Density t (min) 0 100 200 300 400 500 600 700 800 0.70 0.75 0.80 0.85 0.90 0.95 1.00 Experimental data Predicted curve for Ea=285 kJ/mol Predicted curve for Ea=500 kJ/mol Relative Density t (min) Fig. 7 Comparison of the predicted densification results with the experimental data for isothermal sintering of ceria at 1200 °C in oxygen atmosphere.
Fig. 8 Comparison of the predicted densification results with the experimental data for isothermal sintering of ceria at 1020 °C in air atmosphere.
These experimental data can be fitted by MSC constructed for apparent activation energy of 500 kJ/mol.
Online since: September 2022
Authors: Mohammad R. Alenezi, Abdullah M. Almeshal, Abdullah N.F.N.R. Alkhaledi
The improvement in the photocatalytic performance was ascribed to the reduction in dimensionality, the ultrahigh surface-to-volume ratio, the expanded proportion of the exposed polar area, and the creation of nano-junctions between the secondary nanowires and initial ZnO nanowires or nanodiscs.
In principle, organic pollutant photodegradation is a surface oxidation-reduction process which is driven by photogenerated electron-hole pairs [7,8].
Much research exists on the theoretical calculations and experimental data of the part played by the chemistry defects of the ZnO surface and the chemisorption effects [23,24].
The improvement in the photocatalytic performance was ascribed to the reduction in dimensionality, the ultrahigh surface-to-volume ratio, the expanded proportion of the exposed polar area, and the creation of nano-junctions between the secondary nanowires and initial ZnO nanowires or nanodiscs.
The enhanced photocatalytic activity of the ZnO HNWs and HNDs were attributed to the reduction in size and the ultrahigh surface-to-volume ratio and increased proportion of exposed polar facets compared to those of the other tested mono-morphological nanomaterials.
In principle, organic pollutant photodegradation is a surface oxidation-reduction process which is driven by photogenerated electron-hole pairs [7,8].
Much research exists on the theoretical calculations and experimental data of the part played by the chemistry defects of the ZnO surface and the chemisorption effects [23,24].
The improvement in the photocatalytic performance was ascribed to the reduction in dimensionality, the ultrahigh surface-to-volume ratio, the expanded proportion of the exposed polar area, and the creation of nano-junctions between the secondary nanowires and initial ZnO nanowires or nanodiscs.
The enhanced photocatalytic activity of the ZnO HNWs and HNDs were attributed to the reduction in size and the ultrahigh surface-to-volume ratio and increased proportion of exposed polar facets compared to those of the other tested mono-morphological nanomaterials.
Online since: January 2010
Authors: Henryk Dyja, Konrad Błażej Laber, Sebastian Mróz
The paper presents results of theoretical and experimental studies on the influence of strip
temperature reduction at the final stage of the normalizing rolling process in a continuous bar rolling
mill on the energy and force parameters.
Analysis of examination results Heat transfer coefficient values, as computed and taken from technical literature, and other data required for performing numerical modelling of the rolling process under analysis, are given in Table 1.
Input data for computer simulations Process variant Air and water temperatures, airt , watert , [ C° ] Roll temperature rollt , [ C° ] Friction factor, m Coefficient of heat transfer between strip and air, airα , [ KmW 2 / ] Coefficient of heat transfer between strip and rolls, rollα , [ KmW 2 / ] Coefficient of heat transfer between strip and water, waterα , [ KmW 2 / ] Variant 1 20 60 0.8 123 ÷ 138 3000 ÷ 6703 - Variant 2 104 ÷138 3000 ÷ 6431 17500 (after Stand 9) 22500 (after Stand 10) 15000 (after Stand 11) The initial strip temperature was taken based on measurements done during the actual rolling process.
Distribution of temperature after rolling stand no. 12, as obtained from numerical computation (Variant 2) At the subsequent stage of the studies, the effect of strip temperature reduction during the round plain bar normalizing rolling process on the energy and force parameters was determined.
Analysis of examination results Heat transfer coefficient values, as computed and taken from technical literature, and other data required for performing numerical modelling of the rolling process under analysis, are given in Table 1.
Input data for computer simulations Process variant Air and water temperatures, airt , watert , [ C° ] Roll temperature rollt , [ C° ] Friction factor, m Coefficient of heat transfer between strip and air, airα , [ KmW 2 / ] Coefficient of heat transfer between strip and rolls, rollα , [ KmW 2 / ] Coefficient of heat transfer between strip and water, waterα , [ KmW 2 / ] Variant 1 20 60 0.8 123 ÷ 138 3000 ÷ 6703 - Variant 2 104 ÷138 3000 ÷ 6431 17500 (after Stand 9) 22500 (after Stand 10) 15000 (after Stand 11) The initial strip temperature was taken based on measurements done during the actual rolling process.
Distribution of temperature after rolling stand no. 12, as obtained from numerical computation (Variant 2) At the subsequent stage of the studies, the effect of strip temperature reduction during the round plain bar normalizing rolling process on the energy and force parameters was determined.
Online since: March 2009
Authors: Dario Salinas, Vito Raineri, Filippo Giannazzo, Fabrizio Roccaforte, Martin Rambach
An accurate comparison between the
electrical activation data obtained by FPP and SCM was carried out.
Recently, FPP data on samples implanted at temperatures ranging from RT to 1000 °C with similar energies and doses as in this work were reported [6].
SCM raw data were acquired by using a DI3100 AFM by Veeco with Nanoscope V electronics and equipped with the SCM head.
The electrical activation data obtained by SCM were compared with those obtained by FPP analyses.
An activation energy of 6.3±0.3 eV was estimated by linear fitting of the data.
Recently, FPP data on samples implanted at temperatures ranging from RT to 1000 °C with similar energies and doses as in this work were reported [6].
SCM raw data were acquired by using a DI3100 AFM by Veeco with Nanoscope V electronics and equipped with the SCM head.
The electrical activation data obtained by SCM were compared with those obtained by FPP analyses.
An activation energy of 6.3±0.3 eV was estimated by linear fitting of the data.
Online since: December 2014
Authors: Chao Yan, Wu Yuan, Da Hai Luo, Wei Lin Zheng
PANS computations are compared to the experimental data and the traditional Detached Eddy Simulations (DES), showing their excellent capability of resolving turbulent fluctuations.
The computational results are compared with the experimental data of Driver and Seegmiller [3] to evaluate the model performance for predicting separating and reattaching flows.
PANS gives the most excellent agreement of Cf and Cp with the experimental data in the recirculation region and also the closest reattachment point to the experiment.
The computed Cf and Cp from DES computation are comparable to the experimental data, though a much delayed reattachment is observed.
PANS and DES simulations of flow past a backward-facing step are performed and compared with the experimental data to evaluate their performance for unsteady separated flows.
The computational results are compared with the experimental data of Driver and Seegmiller [3] to evaluate the model performance for predicting separating and reattaching flows.
PANS gives the most excellent agreement of Cf and Cp with the experimental data in the recirculation region and also the closest reattachment point to the experiment.
The computed Cf and Cp from DES computation are comparable to the experimental data, though a much delayed reattachment is observed.
PANS and DES simulations of flow past a backward-facing step are performed and compared with the experimental data to evaluate their performance for unsteady separated flows.
Online since: August 2013
Authors: Hong Yong Huang, Zhi You Guo, Dong Xing Cao, Ming Jun Zhu
In this way we overcome the problem of a significant reduction in luminous efficiency.
According to the above simulation data, the trapezoid structure has a higher optical output power.
According to smallest physical size which the LEDs chip can be achieved, we set four sets of data.
Four sets of data are 8μm, 16μm, 24μm and 32μm.
We use the Monte Carlo ray-tracing method to simulate the four sets of data, and we will get the luminous efficiency which is shown in Fig.6.
According to the above simulation data, the trapezoid structure has a higher optical output power.
According to smallest physical size which the LEDs chip can be achieved, we set four sets of data.
Four sets of data are 8μm, 16μm, 24μm and 32μm.
We use the Monte Carlo ray-tracing method to simulate the four sets of data, and we will get the luminous efficiency which is shown in Fig.6.
Online since: December 2013
Authors: Mohamad Farid Sies, Hanis Zakaria, Bukhari Manshoor, Amir Khalid, Norrizal Mustaffa
Dynapack chassis dynamometer was used to perform the performance data while Autocheck gas/smoke analyzer and Drager were used to obtain the emissions data.
The data obtained at four different engine speed; 1500rpm, 2000rpm, 2500rpm and 3000rpm.The load were varied at 0%, 50% and 100% load conditions.
Two types of emissions analyzer were used to produce emissions data.
To minimize errors and obtain better results, the experiment conducted were repeated three times for each data at the same operating condition.
This may be due to the reduction in viscosity that subsequently results on the improvement in spray characteristics, better air-fuel mixing and better combustion characteristics.
The data obtained at four different engine speed; 1500rpm, 2000rpm, 2500rpm and 3000rpm.The load were varied at 0%, 50% and 100% load conditions.
Two types of emissions analyzer were used to produce emissions data.
To minimize errors and obtain better results, the experiment conducted were repeated three times for each data at the same operating condition.
This may be due to the reduction in viscosity that subsequently results on the improvement in spray characteristics, better air-fuel mixing and better combustion characteristics.
Online since: December 2013
Authors: Nigel J. Simms, Shao Min Wu, Mohammad Asgaryan
The integrated model is validated with historical data from Central Electricity Research Laboratories.The remainder of this paper is structured as follows: Model integration, results and discussion and summary.
Combined model Stress rupture data.
Stress rupture data for the common boiler tube materials (Low and high alloy ferritic and austenitic) are given in C.E.R.L (Central Electricity Research Laboratories) report [7].
Fig. 2 shows the stress rupture data of T22 (2.25Cr-1Mo) for metal temperatures between 450 and 650°C and hoop stress between 10 and 300MPa [7].
These predictions for T22 (2.25Cr-1Mo) were close to the stress rupture data provided by [7] (Fig. 2).
Combined model Stress rupture data.
Stress rupture data for the common boiler tube materials (Low and high alloy ferritic and austenitic) are given in C.E.R.L (Central Electricity Research Laboratories) report [7].
Fig. 2 shows the stress rupture data of T22 (2.25Cr-1Mo) for metal temperatures between 450 and 650°C and hoop stress between 10 and 300MPa [7].
These predictions for T22 (2.25Cr-1Mo) were close to the stress rupture data provided by [7] (Fig. 2).
Online since: August 2021
Authors: Aleksey N. Shapovalov, Lilya A. Ayvazyan, Nadezhda K. Nikoli
The Purpose and Object of the Study
The aim of the research is to improve the continuous casting technology of round blooms based on the analysis of production data on the blooms quality and casting parameters.
The research was conducted on the basis of data on the operation of 4-strand bloom caster JSC “Ural Steel” curvilinear type.
Calculated data on the surface temperature dynamics of a 455 mm diameter round bloom within the secondary cooling zone at current and optimum coolant flow rates (at normal overheating) are shown in figure 3.
The data in Fig. 3 confirms that under the current secondary cooling and casting temperature-rate regimes, overcooling of the round bloom surface occurs in the first two segments of secondary cooling, which leads to additional thermal and phase stresses.
Conclusion The analysis of production data on casting of round blooms 455 mm in diameter (from steel grade “2”) at blooming caster of JSC “Ural Steel” has allowed to establish the main reasons for unsatisfactory quality of billet, which consist of increased steel overheat in the tundish and irrational of secondary cooling mode.
The research was conducted on the basis of data on the operation of 4-strand bloom caster JSC “Ural Steel” curvilinear type.
Calculated data on the surface temperature dynamics of a 455 mm diameter round bloom within the secondary cooling zone at current and optimum coolant flow rates (at normal overheating) are shown in figure 3.
The data in Fig. 3 confirms that under the current secondary cooling and casting temperature-rate regimes, overcooling of the round bloom surface occurs in the first two segments of secondary cooling, which leads to additional thermal and phase stresses.
Conclusion The analysis of production data on casting of round blooms 455 mm in diameter (from steel grade “2”) at blooming caster of JSC “Ural Steel” has allowed to establish the main reasons for unsatisfactory quality of billet, which consist of increased steel overheat in the tundish and irrational of secondary cooling mode.
Online since: September 2016
Authors: Yu.I. Kretova, S.P. Merenkova, A.A. Lukin
Under these conditions, hydrolysis of starch and a significant reduction in the solubility of protein fractions.
Table 1 presents experimental data of research of degree of influence of electrophysical effects on the development of fungi of the genus Aspergillus in barley grain.
Experimental research data.
Data on the reaction of fungi of the genus Penicillium on the effect of microwave fields are presented in Table. 2.
Experimental research data Number options The heating temperature, [°C] The infestation of fungal infection [%] р.
Table 1 presents experimental data of research of degree of influence of electrophysical effects on the development of fungi of the genus Aspergillus in barley grain.
Experimental research data.
Data on the reaction of fungi of the genus Penicillium on the effect of microwave fields are presented in Table. 2.
Experimental research data Number options The heating temperature, [°C] The infestation of fungal infection [%] р.