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Online since: June 2019
Authors: Urs A. Peuker, Christos G. Aneziris, Thomas Leißner, Jens Fruhstorfer, Jana Hubálková
A (partial) carbothermal reduction of
alumina at 1550 ◦C was proposed.
In order to attain volume data of a sufficient resolution as well as an appropriate size (3D field of view (FOV)), the scans had voxel sizes of 2.7 µm.
During the reduction, the corresponding gaseous species and also CO formed.
Carbothermic reduction of alumina at 1823K: On the role of molten iron and reaction mechanisms.
Calciothermic reduction of TiO2: A diagrammatic assessment of the thermodynamic limit of deoxidation.
In order to attain volume data of a sufficient resolution as well as an appropriate size (3D field of view (FOV)), the scans had voxel sizes of 2.7 µm.
During the reduction, the corresponding gaseous species and also CO formed.
Carbothermic reduction of alumina at 1823K: On the role of molten iron and reaction mechanisms.
Calciothermic reduction of TiO2: A diagrammatic assessment of the thermodynamic limit of deoxidation.
Online since: January 2013
Authors: Si Zhang, Yue Lin Zhu, Jia Song
The ultra-fine silver powders were prepared by chemical reduction using nitric acid silver (AgNO3) as raw material, ascorbic acid (C6H8O6) as deoxidizer and adding polyvinylpyrrolidone (PVP) as dispersing agent.
Tthe reduction capacity of ascorbic acid increasesd with the increase of pH value, because ofowing to the decrease of E value.
(语法有问题) Ascorbic acid has excellent reduction capacity as a kind of unsaturated sugar acid lactone
Thus the reduction rate for the reaction of (1) can be adjusted by changing pH value.
The lattice constant calculated from this pattern were 2.359, 2.044, 1.444 and 1.231, which agree with the published data JCPDS. 4.Conclusion The ultra-fine silver powders with spherical, controllable size (0.5~2μm) have been synthesized via a wet chemical reaction.
Tthe reduction capacity of ascorbic acid increasesd with the increase of pH value, because ofowing to the decrease of E value.
(语法有问题) Ascorbic acid has excellent reduction capacity as a kind of unsaturated sugar acid lactone
Thus the reduction rate for the reaction of (1) can be adjusted by changing pH value.
The lattice constant calculated from this pattern were 2.359, 2.044, 1.444 and 1.231, which agree with the published data JCPDS. 4.Conclusion The ultra-fine silver powders with spherical, controllable size (0.5~2μm) have been synthesized via a wet chemical reaction.
Online since: July 2012
Authors: Mohammad Azmi Bustam, Siti Munirah Hasanaly, Zakaria Man
Based on literature, the next irreversible reaction for tin phosphate based system is often assigned to the reduction of tin phosphate to form the irreversible lithium phosphate phases (Li3PO4 and LiPO3) [14].
However, for this synthesized mesoporous SnP2O7, it was discovered that there are two energetically different environments for the reduction of SnP2O7 to occur.
It was hypothesized that some partially reduced tin phosphate (Sn0.5PO3) may be formed simultaneously during the initial reduction reaction of mesoporous SnP2O7 at the potential site of 1.10 V.
Therefore, the reduction reaction in the first cycle for mesoporous SnP2O7 was assumed to proceed in the following stepwise order; The irreversible electrochemical reactions at 1.10 V and 0.69 V are attributed to reaction (1) and (2), respectively.
Relating the pore size data with the cycling behaviour of the mesoporous SnP2O7 anodes observed in Figure 4 revealed that capacity retention tends to increase with increasing pore size.
However, for this synthesized mesoporous SnP2O7, it was discovered that there are two energetically different environments for the reduction of SnP2O7 to occur.
It was hypothesized that some partially reduced tin phosphate (Sn0.5PO3) may be formed simultaneously during the initial reduction reaction of mesoporous SnP2O7 at the potential site of 1.10 V.
Therefore, the reduction reaction in the first cycle for mesoporous SnP2O7 was assumed to proceed in the following stepwise order; The irreversible electrochemical reactions at 1.10 V and 0.69 V are attributed to reaction (1) and (2), respectively.
Relating the pore size data with the cycling behaviour of the mesoporous SnP2O7 anodes observed in Figure 4 revealed that capacity retention tends to increase with increasing pore size.
Online since: November 2011
Authors: Xia Jie Jin, Wen Liang Wu, Ke Li Xing
Part V: the volume reduction design.
Finally, store data file as ncl format to prepare for processing.
Generate machine control data file by CL data file, and transfer to the machine controller.
In this paper, SIEMENS CNC system for example, shows application of software WINPCIN data transfer with CNC system [5] [6].
Click soft key “Read In” to make CNC in the state for reception, and in WINPCIN software click the “Send Data” button to select the program file to complete data transmission [9].
Finally, store data file as ncl format to prepare for processing.
Generate machine control data file by CL data file, and transfer to the machine controller.
In this paper, SIEMENS CNC system for example, shows application of software WINPCIN data transfer with CNC system [5] [6].
Click soft key “Read In” to make CNC in the state for reception, and in WINPCIN software click the “Send Data” button to select the program file to complete data transmission [9].
Online since: September 2020
Authors: Sroisiri Thaweboon, Boonyanit Thaweboon, Pakpoom Kedcharoen, Natthamet Wongsirichat
The percentage of biofilm reduction was 40.8%.
In the case of C. glabrata, no significant biofilm reduction was examined among all groups.
Microorganisms 0 Vanillin 0.1% 0.5% S. mutans 0.742+0.239 0.750+0.310 0.439+0.192** C. glabrata 0.321+0.137 0.279+0.028 0.298+0.089 *data expressed as mean optical density+ SD 0% vanillin was used as a control **significant difference from 0% vanillin Fig. 1 Percentage of biofilm reduction in vanillin-incorporated resin groups compared with 0% vanillin group.
It was found that 0.5% vanillin incorporated resin exhibited significant inhibitory effect against S. mutans biofilm formation with a percentage of reduction of 40.8%.
The results of this study were in agreement with our previous study on orthodontic resin [21] which reported 30% S. mutans biofilm reduction in 0.5% vanillin incorporated resin compared with a control.
In the case of C. glabrata, no significant biofilm reduction was examined among all groups.
Microorganisms 0 Vanillin 0.1% 0.5% S. mutans 0.742+0.239 0.750+0.310 0.439+0.192** C. glabrata 0.321+0.137 0.279+0.028 0.298+0.089 *data expressed as mean optical density+ SD 0% vanillin was used as a control **significant difference from 0% vanillin Fig. 1 Percentage of biofilm reduction in vanillin-incorporated resin groups compared with 0% vanillin group.
It was found that 0.5% vanillin incorporated resin exhibited significant inhibitory effect against S. mutans biofilm formation with a percentage of reduction of 40.8%.
The results of this study were in agreement with our previous study on orthodontic resin [21] which reported 30% S. mutans biofilm reduction in 0.5% vanillin incorporated resin compared with a control.
Online since: November 2005
Authors: John J. Jonas, Evgueni I. Poliak
It is shown that the kinetics of softening between mill passes can be modeled more
simply when the normalized strain (reduction) per pass is employed rather than the conventional
strain.
(7) -8.5 -7.5 -6.5 -5.5 -4.5 -3.5 -2.5 1.6 1.8 2 2.2 2.4 log σi log τ50 900 C 950 C 1050 C 1 sec -1 Eq. 7 allows for a radical reduction in the number of experiments required to characterize the rate of post-deformation softening, provided data regarding the Z-dependence of the peak stress are available and the strain hardening behavior is obtained beforehand by the analytical or numerical differentiation of continuous (uninterrupted) flow curves.
When corrections to the downstream stands are made in this way, the pass reductions (and consequently the pass speeds) are changed locally causing further variations in the softening kinetics.
By contrast, with the θ-based approach, the value of the strain hardening rate in successive stands can be readily computed, the changes in the softening kinetics assessed and fed forward, and then the pass reductions corrected accordingly to minimize the variations in gauge and microstructure.
This allows for: 1) A radical reduction in the number of experiments required to generate sufficient data for modeling the post-deformation softening behavior; 2) A description of "strain accumulation" due to incomplete interpass softening in multipass hot rolling in terms of the strain hardening rate. 3) Significant simplification of the extrapolation of laboratory results to industrial high strain rate multipass processing.
(7) -8.5 -7.5 -6.5 -5.5 -4.5 -3.5 -2.5 1.6 1.8 2 2.2 2.4 log σi log τ50 900 C 950 C 1050 C 1 sec -1 Eq. 7 allows for a radical reduction in the number of experiments required to characterize the rate of post-deformation softening, provided data regarding the Z-dependence of the peak stress are available and the strain hardening behavior is obtained beforehand by the analytical or numerical differentiation of continuous (uninterrupted) flow curves.
When corrections to the downstream stands are made in this way, the pass reductions (and consequently the pass speeds) are changed locally causing further variations in the softening kinetics.
By contrast, with the θ-based approach, the value of the strain hardening rate in successive stands can be readily computed, the changes in the softening kinetics assessed and fed forward, and then the pass reductions corrected accordingly to minimize the variations in gauge and microstructure.
This allows for: 1) A radical reduction in the number of experiments required to generate sufficient data for modeling the post-deformation softening behavior; 2) A description of "strain accumulation" due to incomplete interpass softening in multipass hot rolling in terms of the strain hardening rate. 3) Significant simplification of the extrapolation of laboratory results to industrial high strain rate multipass processing.
Online since: December 2018
Authors: Athanasios Vazdirvanidis, Marianna Katsivarda, Nikos Kolioubas, Sofia Papadopoulou, Eugenia Spiropoulou, Spyros Papaefthymiou, Andreas Rikos, George Pantazopoulos
The resulting mean diameter and aspect ratio data generated by such measurements using OM and image analysis of the intermetallics, that are relevant to the extent of beta-to-alpha transformation, are statistically processed with “ANOVA”.
Analysis of Variance (ANOVA) was performed for statistical processing of mean aspect ratio and mean diameter data of AlFeSi intermetallic particles.
Statistical analysis of the raw data of aspect ratio and mean diameter of AlFeSi intermetallics with ANOVA indicated that: (i) The aspect ratio of AlFeSi particles in the as cast (AC) condition was 5.8 (Table 2), which was the highest value compared with the homogenized samples which had 3.2-4.0 for homogenization at 560oC and 2.8-4.3 for homogenization at 585oC.
Lack of cohesion is also restricted a fact that becomes apparent from the reduction of standard deviation in comparison to the as cast condition
· ANOVA is a useful tool for comparing a large amount of data, through the provision of visualized interpretations of the results.
Analysis of Variance (ANOVA) was performed for statistical processing of mean aspect ratio and mean diameter data of AlFeSi intermetallic particles.
Statistical analysis of the raw data of aspect ratio and mean diameter of AlFeSi intermetallics with ANOVA indicated that: (i) The aspect ratio of AlFeSi particles in the as cast (AC) condition was 5.8 (Table 2), which was the highest value compared with the homogenized samples which had 3.2-4.0 for homogenization at 560oC and 2.8-4.3 for homogenization at 585oC.
Lack of cohesion is also restricted a fact that becomes apparent from the reduction of standard deviation in comparison to the as cast condition
· ANOVA is a useful tool for comparing a large amount of data, through the provision of visualized interpretations of the results.
Online since: October 2010
Authors: Vilma Ducman, Urška Lavrenčič Štangar, Marko Kete, Urh Černigoj
The data reported herein correspond to the stable value of the angles obtained by averaging three repeated measurements.
Upon illumination, the dye is reduced by the photogenerated electrons to the form of a different colour (resazurin reduction) [6] or to the bleached form (2,6-dichloroindophenol reduction) [7].
A fitting of the data according to a simplified kinetic analysis has been performed for the initial degradation (till the plateau).
(2) The fitted curves for three different photocatalyst surfaces are presented in Fig. 9 and the correlation between experimental and fitted data is fairly valid for the initial irradiation time.
In order to quantify the data, the time to achieve half decrease of the initial CA was obtained from the curves and the data are collected together with the fluorescence data in Table 1.
Upon illumination, the dye is reduced by the photogenerated electrons to the form of a different colour (resazurin reduction) [6] or to the bleached form (2,6-dichloroindophenol reduction) [7].
A fitting of the data according to a simplified kinetic analysis has been performed for the initial degradation (till the plateau).
(2) The fitted curves for three different photocatalyst surfaces are presented in Fig. 9 and the correlation between experimental and fitted data is fairly valid for the initial irradiation time.
In order to quantify the data, the time to achieve half decrease of the initial CA was obtained from the curves and the data are collected together with the fluorescence data in Table 1.
Online since: November 2012
Authors: Saíd Jalali, Joana Faria, F. Pacheco-Torgal
Cepinha et al. [3] argue that energy efficiency could easily lead to a reduction by one fifth of the energy consumed in the residential sector implying a reduction of 340 Mt of carbon dioxide.
Data of electricity and gas consumption is present in Table 1.
Embodied energy in concrete represents 70% of the total; therefore, high energy reductions can only occur by lowering the energy in this material.
This means that the mere change of concrete composition would mean a 25% embodied energy reduction.
However, as the legislation on energy efficiency lead to a building sector with minimal energy consumption, further energy reduction can only be achieved by using low embodied energy building materials.
Data of electricity and gas consumption is present in Table 1.
Embodied energy in concrete represents 70% of the total; therefore, high energy reductions can only occur by lowering the energy in this material.
This means that the mere change of concrete composition would mean a 25% embodied energy reduction.
However, as the legislation on energy efficiency lead to a building sector with minimal energy consumption, further energy reduction can only be achieved by using low embodied energy building materials.
Online since: February 2019
Authors: Ivan V. Ivanov, Elizaveta I. Tkachenko, Alexander Thoemmes
For corrosion analysis the specimens were cut and grinded using SiC sandpaper with gradual reduction of grain size to 1000 grit.
All corrosion resistance data in work are presented relative to the hydrogen reference electrode.
Metal/alloy Potential, V AISI 304 (18% Cr and 8% Ni) 0.36 Fe12Cr 0.2 Ni - 0.28 Cr > 1.0 Ti > 1.0 When considering the mechanism of crevice corrosion, it is necessary to understand that the electrochemical corrosion of metals in neutral media passes via two independent reactions: reduction of protons to hydrogen (Eq. 1-3) and reduction of dissolved oxygen to hydroxyl anions (Eq. 4-6).
Anode dissolution: Me0 → Men++ ne̅ (1) Cathode reduction: 2H+ + 2e ̅→ H2 (2) Corrosion mechanism: nMe0 + nH+ → nMen+ + H2 (3) Anode dissolution: Me0 → Men++ ne̅ (4) Cathode reduction: O2 + 2H2O + 4e ̅→ 4OH- (5) Corrosion mechanism: Me0 + O2 + H2O →Me(OH )n↓ (6) Initially, corrosion occurs evenly over the entire surface of the metal.
There is no oxygen reduction reaction in this region, however, the dissolution of the metal continues.
All corrosion resistance data in work are presented relative to the hydrogen reference electrode.
Metal/alloy Potential, V AISI 304 (18% Cr and 8% Ni) 0.36 Fe12Cr 0.2 Ni - 0.28 Cr > 1.0 Ti > 1.0 When considering the mechanism of crevice corrosion, it is necessary to understand that the electrochemical corrosion of metals in neutral media passes via two independent reactions: reduction of protons to hydrogen (Eq. 1-3) and reduction of dissolved oxygen to hydroxyl anions (Eq. 4-6).
Anode dissolution: Me0 → Men++ ne̅ (1) Cathode reduction: 2H+ + 2e ̅→ H2 (2) Corrosion mechanism: nMe0 + nH+ → nMen+ + H2 (3) Anode dissolution: Me0 → Men++ ne̅ (4) Cathode reduction: O2 + 2H2O + 4e ̅→ 4OH- (5) Corrosion mechanism: Me0 + O2 + H2O →Me(OH )n↓ (6) Initially, corrosion occurs evenly over the entire surface of the metal.
There is no oxygen reduction reaction in this region, however, the dissolution of the metal continues.