The Experts below are selected from a list of 8160 Experts worldwide ranked by ideXlab platform
Ernesto C. Pereira - One of the best experts on this subject based on the ideXlab platform.
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Fractional Factorial Design applied to investigate properties of Ti/IrO2–Nb2O5 electrodes
Electrochimica Acta, 2000Co-Authors: Ailton José Terezo, Ernesto C. PereiraAbstract:The effects of the preparation variables on the electrochemical and morphological properties of Ti/IrO2–Nb2O5 (60:40 mol%) electrodes prepared by the polymeric precursor method were investigated. In order to reduce the number of experiments, the study was carried out using a two-level Fractional Factorial Design with resolution III. It was observed that the charge depends mainly on the temperature of calcination and on the composition of the precursor solution. An average decrease of 26.9 (mC cm−2 mg−1) was observed by changing the calcination temperature from 400 to 500°C. The average anodic charge decreased by 8.93 (mC cm−2 mg−1) when the molar ratio CA/EG (citric acid/ethylene glycol) was changed from 1:6 to 1:12. A similar behaviour was observed when the molar ratio between CA/PS (citric acid/precursor salt) was changed from 6:1 to 12:1, a decrease of 10.3 (mC cm−2 mg−1) being observed. The anodic charge decrease also occurred by increasing the time of calcination as well as controlling the heating rate. Once the temperature was the main variable affecting the anodic charge it was widely investigated in a range between 250 and 700°C. A maximum anodic charge was observed at 300°C while the electrode calcinated at 600°C showed the maximum value in the accelerated stability test (AST) for the oxygen evolving reaction in acid medium. The effects observed on the electrochemical properties were correlated with the morphological and microstructural changes occurring in the samples.
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Fractional Factorial Design applied to investigate properties of ti iro2 nb2o5 electrodes
Electrochimica Acta, 2000Co-Authors: Ailton José Terezo, Ernesto C. PereiraAbstract:The effects of the preparation variables on the electrochemical and morphological properties of Ti/IrO2–Nb2O5 (60:40 mol%) electrodes prepared by the polymeric precursor method were investigated. In order to reduce the number of experiments, the study was carried out using a two-level Fractional Factorial Design with resolution III. It was observed that the charge depends mainly on the temperature of calcination and on the composition of the precursor solution. An average decrease of 26.9 (mC cm−2 mg−1) was observed by changing the calcination temperature from 400 to 500°C. The average anodic charge decreased by 8.93 (mC cm−2 mg−1) when the molar ratio CA/EG (citric acid/ethylene glycol) was changed from 1:6 to 1:12. A similar behaviour was observed when the molar ratio between CA/PS (citric acid/precursor salt) was changed from 6:1 to 12:1, a decrease of 10.3 (mC cm−2 mg−1) being observed. The anodic charge decrease also occurred by increasing the time of calcination as well as controlling the heating rate. Once the temperature was the main variable affecting the anodic charge it was widely investigated in a range between 250 and 700°C. A maximum anodic charge was observed at 300°C while the electrode calcinated at 600°C showed the maximum value in the accelerated stability test (AST) for the oxygen evolving reaction in acid medium. The effects observed on the electrochemical properties were correlated with the morphological and microstructural changes occurring in the samples.
Yunlin Zhao - One of the best experts on this subject based on the ideXlab platform.
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Ethylenediamine grafted to graphene oxide@Fe3O4 for chromium(VI) decontamination: Performance, modelling, and Fractional Factorial Design
PloS one, 2017Co-Authors: Xu Jiawen, Wu Cuiyu, Deng Jianbin, Liao Wenwei, Ling Yuxiang, Yang Yuanxiu, Zhao Yina, Yunlin ZhaoAbstract:A method for grafting ethylenediamine to a magnetic graphene oxide composite (EDA-GO@Fe3O4) was developed for Cr(VI) decontamination. The physicochemical properties of EDA-GO@Fe3O4 were characterized using HRTEM, EDS, FT-IR, TG-DSC, and XPS. The effects of pH, sorbent dose, foreign anions, time, Cr(VI) concentration, and temperature on decontamination process were studied. The solution pH can largely affect the decontamination process. The pseudo-second-order model is suitable for being applied to fit the adsorption processes of Cr(VI) with GO@Fe3O4 and EDA-GO@Fe3O4. The intra-particle diffusion is not the rate-controlling step. Isotherm experimental data can be described using the Freundlich model. The effects of multiple factors on the Cr(VI) decontamination was investigated by a 25−1 Fractional Factorial Design (FFD). The adsorption process can significantly be affected by the main effects of A (pH), B (Cr(VI) concentration), and E (Adsorbent dose). The combined factors of AB (pH × Cr(VI) concentration), AE (pH × Adsorbent dose), and BC (Cr(VI) concentration × Temperature) had larger effects than other factors on Cr(VI) removal. These results indicated that EDA-GO@Fe3O4 is a potential and suitable candidate for treatment of heavy metal wastewater.
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ethylenediamine grafted to graphene oxide fe3o4 for chromium vi decontamination performance modelling and Fractional Factorial Design
PLOS ONE, 2017Co-Authors: Jianbin Deng, Hui Wang, Yunlin Zhao, Wenwei Liao, Yuxiang Ling, Yuanxiu Yang, Yina Zhao, Yunguo LiuAbstract:A method for grafting ethylenediamine to a magnetic graphene oxide composite (EDA-GO@Fe3O4) was developed for Cr(VI) decontamination. The physicochemical properties of EDA-GO@Fe3O4 were characterized using HRTEM, EDS, FT-IR, TG-DSC, and XPS. The effects of pH, sorbent dose, foreign anions, time, Cr(VI) concentration, and temperature on decontamination process were studied. The solution pH can largely affect the decontamination process. The pseudo-second-order model is suitable for being applied to fit the adsorption processes of Cr(VI) with GO@Fe3O4 and EDA-GO@Fe3O4. The intra-particle diffusion is not the rate-controlling step. Isotherm experimental data can be described using the Freundlich model. The effects of multiple factors on the Cr(VI) decontamination was investigated by a 25−1 Fractional Factorial Design (FFD). The adsorption process can significantly be affected by the main effects of A (pH), B (Cr(VI) concentration), and E (Adsorbent dose). The combined factors of AB (pH × Cr(VI) concentration), AE (pH × Adsorbent dose), and BC (Cr(VI) concentration × Temperature) had larger effects than other factors on Cr(VI) removal. These results indicated that EDA-GO@Fe3O4 is a potential and suitable candidate for treatment of heavy metal wastewater.
Yunguo Liu - One of the best experts on this subject based on the ideXlab platform.
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Optimization of Cadmium Adsorption by Magnetic Graphene Oxide Using a Fractional Factorial Design.
International journal of environmental research and public health, 2020Co-Authors: Hui Wang, Yiming Zhou, Yuan Guo, Xiaoxi Cai, Chunjie Liu, Wang Ping, Yunguo LiuAbstract:Graphene materials have attracted increasing interest in water remediation. In this study, magnetic graphene oxide (MGO) was prepared through the modified Hummers method and the adsorption behaviors of cadmium were investigated. Firstly, the sorption kinetics, isotherms, as well as the effects of pH were investigated. Then, Fractional Factorial Design (FFD) was used to optimize the effects of pH, temperature, time, initial concentration of cadmium ion and NaCl on cadmium adsorption. The results indicate that MGO could effectively remove cadmium ions from an aqueous solution and the sorption data could be described well by pseudo-second-order and Freundlich models, showing that the adsorption rate of cadmium ions on MGO is multilayer adsorption and dominated by the chemical adsorption. According to the FFD results, the maximum adsorption capacity of cadmium ions was 13.169 mg/g under the optimum condition of pH value 8, 45 °C, contact time 60 min, initial cadmium concentration of 70 mg/L and NaCl concentration of 100 mg/L. Higher levels of the pH value, temperature and initial cadmium concentration are beneficial to the adsorption process. These results are important for estimating and optimizing the removal of metal ions by MGO composite.
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ethylenediamine grafted to graphene oxide fe3o4 for chromium vi decontamination performance modelling and Fractional Factorial Design
PLOS ONE, 2017Co-Authors: Jianbin Deng, Hui Wang, Yunlin Zhao, Wenwei Liao, Yuxiang Ling, Yuanxiu Yang, Yina Zhao, Yunguo LiuAbstract:A method for grafting ethylenediamine to a magnetic graphene oxide composite (EDA-GO@Fe3O4) was developed for Cr(VI) decontamination. The physicochemical properties of EDA-GO@Fe3O4 were characterized using HRTEM, EDS, FT-IR, TG-DSC, and XPS. The effects of pH, sorbent dose, foreign anions, time, Cr(VI) concentration, and temperature on decontamination process were studied. The solution pH can largely affect the decontamination process. The pseudo-second-order model is suitable for being applied to fit the adsorption processes of Cr(VI) with GO@Fe3O4 and EDA-GO@Fe3O4. The intra-particle diffusion is not the rate-controlling step. Isotherm experimental data can be described using the Freundlich model. The effects of multiple factors on the Cr(VI) decontamination was investigated by a 25−1 Fractional Factorial Design (FFD). The adsorption process can significantly be affected by the main effects of A (pH), B (Cr(VI) concentration), and E (Adsorbent dose). The combined factors of AB (pH × Cr(VI) concentration), AE (pH × Adsorbent dose), and BC (Cr(VI) concentration × Temperature) had larger effects than other factors on Cr(VI) removal. These results indicated that EDA-GO@Fe3O4 is a potential and suitable candidate for treatment of heavy metal wastewater.
Ailton José Terezo - One of the best experts on this subject based on the ideXlab platform.
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Fractional Factorial Design applied to investigate properties of Ti/IrO2–Nb2O5 electrodes
Electrochimica Acta, 2000Co-Authors: Ailton José Terezo, Ernesto C. PereiraAbstract:The effects of the preparation variables on the electrochemical and morphological properties of Ti/IrO2–Nb2O5 (60:40 mol%) electrodes prepared by the polymeric precursor method were investigated. In order to reduce the number of experiments, the study was carried out using a two-level Fractional Factorial Design with resolution III. It was observed that the charge depends mainly on the temperature of calcination and on the composition of the precursor solution. An average decrease of 26.9 (mC cm−2 mg−1) was observed by changing the calcination temperature from 400 to 500°C. The average anodic charge decreased by 8.93 (mC cm−2 mg−1) when the molar ratio CA/EG (citric acid/ethylene glycol) was changed from 1:6 to 1:12. A similar behaviour was observed when the molar ratio between CA/PS (citric acid/precursor salt) was changed from 6:1 to 12:1, a decrease of 10.3 (mC cm−2 mg−1) being observed. The anodic charge decrease also occurred by increasing the time of calcination as well as controlling the heating rate. Once the temperature was the main variable affecting the anodic charge it was widely investigated in a range between 250 and 700°C. A maximum anodic charge was observed at 300°C while the electrode calcinated at 600°C showed the maximum value in the accelerated stability test (AST) for the oxygen evolving reaction in acid medium. The effects observed on the electrochemical properties were correlated with the morphological and microstructural changes occurring in the samples.
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Fractional Factorial Design applied to investigate properties of ti iro2 nb2o5 electrodes
Electrochimica Acta, 2000Co-Authors: Ailton José Terezo, Ernesto C. PereiraAbstract:The effects of the preparation variables on the electrochemical and morphological properties of Ti/IrO2–Nb2O5 (60:40 mol%) electrodes prepared by the polymeric precursor method were investigated. In order to reduce the number of experiments, the study was carried out using a two-level Fractional Factorial Design with resolution III. It was observed that the charge depends mainly on the temperature of calcination and on the composition of the precursor solution. An average decrease of 26.9 (mC cm−2 mg−1) was observed by changing the calcination temperature from 400 to 500°C. The average anodic charge decreased by 8.93 (mC cm−2 mg−1) when the molar ratio CA/EG (citric acid/ethylene glycol) was changed from 1:6 to 1:12. A similar behaviour was observed when the molar ratio between CA/PS (citric acid/precursor salt) was changed from 6:1 to 12:1, a decrease of 10.3 (mC cm−2 mg−1) being observed. The anodic charge decrease also occurred by increasing the time of calcination as well as controlling the heating rate. Once the temperature was the main variable affecting the anodic charge it was widely investigated in a range between 250 and 700°C. A maximum anodic charge was observed at 300°C while the electrode calcinated at 600°C showed the maximum value in the accelerated stability test (AST) for the oxygen evolving reaction in acid medium. The effects observed on the electrochemical properties were correlated with the morphological and microstructural changes occurring in the samples.
Xu Jiawen - One of the best experts on this subject based on the ideXlab platform.
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Ethylenediamine grafted to graphene oxide@Fe3O4 for chromium(VI) decontamination: Performance, modelling, and Fractional Factorial Design
PloS one, 2017Co-Authors: Xu Jiawen, Wu Cuiyu, Deng Jianbin, Liao Wenwei, Ling Yuxiang, Yang Yuanxiu, Zhao Yina, Yunlin ZhaoAbstract:A method for grafting ethylenediamine to a magnetic graphene oxide composite (EDA-GO@Fe3O4) was developed for Cr(VI) decontamination. The physicochemical properties of EDA-GO@Fe3O4 were characterized using HRTEM, EDS, FT-IR, TG-DSC, and XPS. The effects of pH, sorbent dose, foreign anions, time, Cr(VI) concentration, and temperature on decontamination process were studied. The solution pH can largely affect the decontamination process. The pseudo-second-order model is suitable for being applied to fit the adsorption processes of Cr(VI) with GO@Fe3O4 and EDA-GO@Fe3O4. The intra-particle diffusion is not the rate-controlling step. Isotherm experimental data can be described using the Freundlich model. The effects of multiple factors on the Cr(VI) decontamination was investigated by a 25−1 Fractional Factorial Design (FFD). The adsorption process can significantly be affected by the main effects of A (pH), B (Cr(VI) concentration), and E (Adsorbent dose). The combined factors of AB (pH × Cr(VI) concentration), AE (pH × Adsorbent dose), and BC (Cr(VI) concentration × Temperature) had larger effects than other factors on Cr(VI) removal. These results indicated that EDA-GO@Fe3O4 is a potential and suitable candidate for treatment of heavy metal wastewater.
