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Online since: February 2014
Authors: Jana Stachová, Marcela Fridrichová, Jan Gemrich, Radek Magrla
By influence of establishment of dynamic balance saturated SOx vapours before finished decomposition of calcium sulphate it came up to mentioned effect and by this against draft of substantial reduction of alite in arisen clinker.
The sharper torrid modes 1400oC/5 hours to 1450oC/3 hours has shown as suitable, whose thermal energy is enough to perfect alite synthesis, but it was not insofar high yet to cue consolidation of structure and by this the reduction of reactivity too.
CO2 emission saving, expressed as reduction of carbon dioxide content in given raw powder in relation to similarly drafted raw mixture, in which the whole lime would come only from calcium carbonate, was calculated in level 6,5 % for this clinker.
ISSN 0008-8919 [2] EN 197-1 ed.2, Cement - Part 1: Composition, specifications and conformity criteria for common cements [3] Poon C.S., Kou S.C., Lam L., Lin Z.S.: Activation of Fly Ash/Cement Systems Using Calcium Sulfate Anhydrite (CaSO4), Cement and Concret Research, www.sciencedirect.com, 2001 [4] Chemical Comparison of Fly Ash and Portland Cement, Headwaters Resources, Data 2007 [online], www.flyash.com [5] Sebök, T, Šimoník J, Kulísek K, The compressive strength of samples containing fly ash with high content of calcium sulfate and calcium oxide, Cement and Concrete Research 31 (2001) 1101 – 1107
[7] Fly Ash – Types and Benefits, Headwaters Resources, Data 2007 [online], URL: www.flyash.com
The sharper torrid modes 1400oC/5 hours to 1450oC/3 hours has shown as suitable, whose thermal energy is enough to perfect alite synthesis, but it was not insofar high yet to cue consolidation of structure and by this the reduction of reactivity too.
CO2 emission saving, expressed as reduction of carbon dioxide content in given raw powder in relation to similarly drafted raw mixture, in which the whole lime would come only from calcium carbonate, was calculated in level 6,5 % for this clinker.
ISSN 0008-8919 [2] EN 197-1 ed.2, Cement - Part 1: Composition, specifications and conformity criteria for common cements [3] Poon C.S., Kou S.C., Lam L., Lin Z.S.: Activation of Fly Ash/Cement Systems Using Calcium Sulfate Anhydrite (CaSO4), Cement and Concret Research, www.sciencedirect.com, 2001 [4] Chemical Comparison of Fly Ash and Portland Cement, Headwaters Resources, Data 2007 [online], www.flyash.com [5] Sebök, T, Šimoník J, Kulísek K, The compressive strength of samples containing fly ash with high content of calcium sulfate and calcium oxide, Cement and Concrete Research 31 (2001) 1101 – 1107
[7] Fly Ash – Types and Benefits, Headwaters Resources, Data 2007 [online], URL: www.flyash.com
Online since: September 2008
Authors: Krzysztof Wolski, Michèle Pijolat, Céline Cabet, Gouenou Girardin, Jerome Chapovaloff, Fabien Rouillard
Role of chromium in the chromia reduction.
Exception made of the point in He-In1, the experimental TA for both commercial alloys in Fig. 6 globally follow the general trend predicted through (Eq. 3) and the results obtained on Inconel 617 are in good agreement with the data from reference [9].
The experimental data at low P(CO) (bottom of the graph) show a deviation toward curves for higher a(Cr).
Besides, it was elsewhere [6] demonstrated for Inconel 617 that the partial pressure of water vapour during step 1 (oxidation at 850°C) influences the value of TA, but in Fig. 6 we gather data irrespective of the atmosphere moisture in the range 0.5-6 µbar.
Therefore, the relevant thermodynamic data have to be the interfacial activities which could be significantly different from the bulk values.
Exception made of the point in He-In1, the experimental TA for both commercial alloys in Fig. 6 globally follow the general trend predicted through (Eq. 3) and the results obtained on Inconel 617 are in good agreement with the data from reference [9].
The experimental data at low P(CO) (bottom of the graph) show a deviation toward curves for higher a(Cr).
Besides, it was elsewhere [6] demonstrated for Inconel 617 that the partial pressure of water vapour during step 1 (oxidation at 850°C) influences the value of TA, but in Fig. 6 we gather data irrespective of the atmosphere moisture in the range 0.5-6 µbar.
Therefore, the relevant thermodynamic data have to be the interfacial activities which could be significantly different from the bulk values.
Online since: July 2015
Authors: Mohamed Nur Shafiq Mohamed Hanif, Mohd Shalahuddin Adnan, Nurul Syakeera Nordin, Mohamad Azim Mohammad Azmi, Aeslina Abdul Kadir, Saiful Azhar Ahmad Tajudin
The results indicate that with 7.5% of treated sugarcane bagasse replacement in cement resulted significant reduction of lead contaminant in soil up to 99 % after 28 days.
The leaching data collected through laboratory leaching tests could estimate and simulate the behavior of waste under ideal, static or worst case field condition.
The highest reduction of lead concentration was occurred in a sample with additional of 7.5% OPC + 7.5% treated SCB which is 99.58% reduction with pH 5.12 to 12.96.
The significant reduction occurred due to two main mechanisms which are microencapsulation process and chemical fixation [10].
However, based on TCLP and SPLP result after treatment, shows that by using treated SCB (sample G, H and I) there have a significant reduction of lead leachability up to 99.6%.
The leaching data collected through laboratory leaching tests could estimate and simulate the behavior of waste under ideal, static or worst case field condition.
The highest reduction of lead concentration was occurred in a sample with additional of 7.5% OPC + 7.5% treated SCB which is 99.58% reduction with pH 5.12 to 12.96.
The significant reduction occurred due to two main mechanisms which are microencapsulation process and chemical fixation [10].
However, based on TCLP and SPLP result after treatment, shows that by using treated SCB (sample G, H and I) there have a significant reduction of lead leachability up to 99.6%.
Online since: April 2005
Authors: M. Rekas, M. Radecka
The aim of this work is, basing on defect model, comparison of chemical diffusion coefficient
with atomic diffusion data in titanium dioxide.
As can be seen, good agreement between experimental and theoretical data is observed.
The statistical analysis showed that there are no differences between both sets of these data.
As can be seen the best agreement was achieved for A = 0.1 at.% and literature data of DO and DTi [11,12], respectively.
Conclusions Chemical diffusion coefficient in TiO2 single crystal within n-p transition range was determined from electrical conductivity transient data.
As can be seen, good agreement between experimental and theoretical data is observed.
The statistical analysis showed that there are no differences between both sets of these data.
As can be seen the best agreement was achieved for A = 0.1 at.% and literature data of DO and DTi [11,12], respectively.
Conclusions Chemical diffusion coefficient in TiO2 single crystal within n-p transition range was determined from electrical conductivity transient data.
Online since: September 2013
Authors: Zhan Jun Jiang, Yu Hong Liu, Dong Mei Zhou
Simulation results show that the proposed algorithm is superior to the conventional SS method, not only in the improvement of output SNR, but in the reduction of the speech distortion and residual musical noise.
In lower SNR conditions, it’s difficult to find the best tradeoff between the amount of noise reduction, the speech distortion and the level of residual noise in a perceptual sense.
In order to reduce the effect of the annoying musical noise, the form of SS algorithm is modified as [8]: (6) where α is the over-subtraction factor which determines the balance of the amount of noise reduction and speech distortion β is the noise spectral flooring which is the addition of background noise in order to mask the residual noise. γ1 and γ2 are the exponent factors, the typical values of γ1 and γ2 are 1 and 2 respectively.
Signal spectral is obtained by using Fast Fourier Transform over the Hamming windowed, half-overlapped input data buffer.
The power spectral of the windowed data is calculated and subtracted by the average noise spectral calculated during non-speech period.
In lower SNR conditions, it’s difficult to find the best tradeoff between the amount of noise reduction, the speech distortion and the level of residual noise in a perceptual sense.
In order to reduce the effect of the annoying musical noise, the form of SS algorithm is modified as [8]: (6) where α is the over-subtraction factor which determines the balance of the amount of noise reduction and speech distortion β is the noise spectral flooring which is the addition of background noise in order to mask the residual noise. γ1 and γ2 are the exponent factors, the typical values of γ1 and γ2 are 1 and 2 respectively.
Signal spectral is obtained by using Fast Fourier Transform over the Hamming windowed, half-overlapped input data buffer.
The power spectral of the windowed data is calculated and subtracted by the average noise spectral calculated during non-speech period.
Online since: December 2013
Authors: Ashot Tamrazyan
It is possible to reveal the influence of the dynamic effect on the reduction of the bearing capacity of the pylon and fire and columns of 40%.
Table 1 The results of the calculation of heating The Point of section 60 min 90 min 120 min 150 min 180 min 210 min 240 min Corner point(˚C) 934 999 1045 1079 1107 1131 1151 The middle of the side face (˚C) 868 950 1004 1044 1077 1103 1126 Reinforcement steel (˚C) 156 261 342 407 461 507 548 On the basis of temperature fields by using the Eq.1: N≤φ(γbtRbnAb+γstRbnAs) , (1) where and - reduction factors for concrete and reinforcement, following results were obtained calculating the pylon(Fig. 1) .
(4) Heating concrete over (100) ° C generally leads to defects in its structure and reduction in strength.
Fig. 2.Graph of the dynamics coefficient of concrete depending on temperature Generalizing the data obtained from the calculation of the bearing capacity of the column for four cases was built the following diagram (Fig.3).
Table 1 The results of the calculation of heating The Point of section 60 min 90 min 120 min 150 min 180 min 210 min 240 min Corner point(˚C) 934 999 1045 1079 1107 1131 1151 The middle of the side face (˚C) 868 950 1004 1044 1077 1103 1126 Reinforcement steel (˚C) 156 261 342 407 461 507 548 On the basis of temperature fields by using the Eq.1: N≤φ(γbtRbnAb+γstRbnAs) , (1) where and - reduction factors for concrete and reinforcement, following results were obtained calculating the pylon(Fig. 1) .
(4) Heating concrete over (100) ° C generally leads to defects in its structure and reduction in strength.
Fig. 2.Graph of the dynamics coefficient of concrete depending on temperature Generalizing the data obtained from the calculation of the bearing capacity of the column for four cases was built the following diagram (Fig.3).
Online since: September 2017
Authors: D.M. Grintsov, M.O. Korovkin
However, there are data that show that joint grinding of superplasticizers and cement is not effective in mixtures with low water-cement ratio at cement grinding to a specific surface area of 450 m2/ kg [19].
Cement 3 65.4±4.7 13.8±4.1 9.5±1.7 11.3±2.5 0.53 ± 0.15 0.29 ±0.2 0.6 ±0.08 * According to the manufacturer data Results and Discussion The dependence of water-reducing effect of the SP on the time of determining the consistency of hard and poor plastic mixtures (mixture flow on a jolting table 110 and 190 mm, respectively) at different methods of additives introducing is shown in Table 2.
Cement 3 350 hard at grinding 18.5 18.6 17.1 15.7 13.9 17.7 16.3 powder 24.0 20.9 19.6 16.8 14.7 14.7 9.4 plastic at grinding 16.3 12.6 12.3 12.8 16.7 14.4 1.1 powder 18.2 13.3 9.8 10.2 11.9 6.6 0.0 450 hard at grinding 12.9 14.1 22.1 23.7 23.8 19.0 12.5 powder 26.8 18.4 18.2 20.0 22.2 22.8 21.1 plastic at grinding 18.2 11.3 6.8 1.5 -4.1 -7.3 -4.5 powder 17.3 16.6 14.8 13.0 11.4 4.9 4.0 As we can see from the data shown in Table 2, almost for all compositions the efficiency of two methods of SP S-3 introduction is approximately at the same level.
These data are consistent with the results of research obtained in [19].
Influence of a Superplasticizer on Cement Grinding and Its Activity Reduction During Storage, Procedia Engineering, 150 (2016) 1600-1604.
Cement 3 65.4±4.7 13.8±4.1 9.5±1.7 11.3±2.5 0.53 ± 0.15 0.29 ±0.2 0.6 ±0.08 * According to the manufacturer data Results and Discussion The dependence of water-reducing effect of the SP on the time of determining the consistency of hard and poor plastic mixtures (mixture flow on a jolting table 110 and 190 mm, respectively) at different methods of additives introducing is shown in Table 2.
Cement 3 350 hard at grinding 18.5 18.6 17.1 15.7 13.9 17.7 16.3 powder 24.0 20.9 19.6 16.8 14.7 14.7 9.4 plastic at grinding 16.3 12.6 12.3 12.8 16.7 14.4 1.1 powder 18.2 13.3 9.8 10.2 11.9 6.6 0.0 450 hard at grinding 12.9 14.1 22.1 23.7 23.8 19.0 12.5 powder 26.8 18.4 18.2 20.0 22.2 22.8 21.1 plastic at grinding 18.2 11.3 6.8 1.5 -4.1 -7.3 -4.5 powder 17.3 16.6 14.8 13.0 11.4 4.9 4.0 As we can see from the data shown in Table 2, almost for all compositions the efficiency of two methods of SP S-3 introduction is approximately at the same level.
These data are consistent with the results of research obtained in [19].
Influence of a Superplasticizer on Cement Grinding and Its Activity Reduction During Storage, Procedia Engineering, 150 (2016) 1600-1604.
Online since: April 2014
Authors: Wei Hua Zeng, Zhe Liu
However, their true ability of contribution to greenhouse gas (GHG) emissions reductions is invisible.
There is, therefore, a demand to develop alternatives motivated by the reduction of the dependency on fossil fuel due to the limited resources.
It can also fully support data collection and record the original parameters and the data collecting process.
The data we use is coming from CLCD and all of them are background data.
In this study, we choose global warming potential and acidification as the characterization factors, the normalization reference of China in 2010 as the normalization, the ECER-125 (twelfth five year energy conservation and emission reduction overall indicator) as the weighted comprehension targets.
There is, therefore, a demand to develop alternatives motivated by the reduction of the dependency on fossil fuel due to the limited resources.
It can also fully support data collection and record the original parameters and the data collecting process.
The data we use is coming from CLCD and all of them are background data.
In this study, we choose global warming potential and acidification as the characterization factors, the normalization reference of China in 2010 as the normalization, the ECER-125 (twelfth five year energy conservation and emission reduction overall indicator) as the weighted comprehension targets.
Online since: October 2007
Authors: S. Endo, T. Yokota, H. Ohtsubo
Slab was reheated at 780°C (ferrite; α +
austenite; γ phase region) and rolled with 90% reduction down to 12mm in thickness using laboratory
mill. 700°C (ferrite; α + cementite; θ phase region) rolled plate was also prepared to compare with 780°C
rolled plate.
The rolling reduction was divided into 20 passes to lighten a load imposed on the mill and average reduction per pass was around 10%.
Deformation stress was derived from experimental data measured by thermo-mechanical simulator in advance.
Fine-grained ferrite is formed by Total reduction 90% Ac3: 880°C α + θ α + γ Ac1: 730°C 780°C 700°C 120mm 12mm grain subdivision, thus dynamic recrystallization process.
The ratio evaluated by SEM micrographs is in good accordance with EBSD data.
The rolling reduction was divided into 20 passes to lighten a load imposed on the mill and average reduction per pass was around 10%.
Deformation stress was derived from experimental data measured by thermo-mechanical simulator in advance.
Fine-grained ferrite is formed by Total reduction 90% Ac3: 880°C α + θ α + γ Ac1: 730°C 780°C 700°C 120mm 12mm grain subdivision, thus dynamic recrystallization process.
The ratio evaluated by SEM micrographs is in good accordance with EBSD data.
Online since: February 2019
Authors: S. Chupin, Victor I. Bolobov
It has been found out that HTMT leads to increase of steel hardness and reduction of wear rate compared to heat treatment applied at manufacture of cutters.
The maximal increase of hardness (by 23%) and reduction of wear rate (by 38%) corresponds to the mode of distortion accumulation of ~1,5 at 900 °С at water quenching and tempering at 230 °C.
Reduction of these resources has been a very urgent issue in the industry and its topicality remains in mining mechanical engineering today.
Influence of thermomechanical treatment on wear resistance of materials is studied insufficiently [13-18] and there is almost no data about its effects on abrasion wear resistance.
Obtained positive effect can be explained by austenite grain refinement and corresponding reduction of martensite crystal sizes (from 20 to 4 micron) which occur during HTMT.
The maximal increase of hardness (by 23%) and reduction of wear rate (by 38%) corresponds to the mode of distortion accumulation of ~1,5 at 900 °С at water quenching and tempering at 230 °C.
Reduction of these resources has been a very urgent issue in the industry and its topicality remains in mining mechanical engineering today.
Influence of thermomechanical treatment on wear resistance of materials is studied insufficiently [13-18] and there is almost no data about its effects on abrasion wear resistance.
Obtained positive effect can be explained by austenite grain refinement and corresponding reduction of martensite crystal sizes (from 20 to 4 micron) which occur during HTMT.