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Yongchun Dong - One of the best experts on this subject based on the ideXlab platform.
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photoassisted degradation of ci reactive red 195 using an Fe iii grafted polytetrafluoroethylene fibre complex as a novel heterogeneous Fenton catalyst over a wide ph range
Coloration Technology, 2013Co-Authors: Yongchun Dong, Zhizhong DingAbstract:Polytetrafluoroethylene fibre was grafted with acrylic acid to form an efFective ligand, which coordinated with Fe(III) ions to prepare an Fe(III)-grafted polytetrafluoroethylene fibre complex. The photoassisted degradation of a typical azo dye, CI Reactive Red 195, using the Fe(III)-grafted polytetrafluoroethylene fibre complex as a novel heterogeneous Fenton catalyst in a wide pH range of 3–9 was investigated. In order to achieve better degradation in a higher pH range, the efFect of Fe Content, incorporation of Cu(II) ions and UV light irradiation on dye degradation was also examined. The results indicated that dye degradation was efFective in the presence of the Fe(III)-grafted polytetrafluoroethylene fibre complex. Fast degradation of the dye can take place in an acidic environment. Increasing the Fe Content or incorporating Cu(II) ions can significantly accelerate dye degradation, and UV light irradiation is much more efFective than visible light irradiation in a higher pH range, especially in the alkaline pH range.
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preparation and catalytic activity of Fe alginate gel beads for oxidative degradation of azo dyes under visible light irradiation
Catalysis Today, 2011Co-Authors: Yongchun Dong, Wenjing Dong, Yanan Cao, Zhenbang Han, Zhizhong DingAbstract:Abstract Fe alginate gel beads were prepared by adding sodium alginate aqueous solution drop-wise into the FeCl3 gelling solution using a syringe needle at room temperature, and measured in terms of size, mass and Fe Content, then characterized using SEM, XRD, FT-IR, XPS and TGA, respectively. The gel beads were evaluated as the heterogeneous Fenton catalysts for oxidative degradation of two typical azo dyes, Reactive Blue 222 and Acid Black 234 in the presence of H2O2 under visible light irradiation. Some important factors afFecting the preparation of the beads and their catalytic function such as FeCl3 concentration, irradiation intensity and pH value were examined. The results indicated that Fe3+ ions coordinated with oxygen atoms in carboxyl groups from glucose chains of alginates to form the Fe alginate gel beads. And Fe3+ ion was a central cation that has a coordination number of 6 in the complex. Higher concentration of FeCl3 solution caused the significant increase in the Fe Content of the gel bead during preparation. Fe alginate gel beads showed a great catalytic role in the degradation of the azo dyes in a wide pH range of 3.0–8.0. Moreover, higher Fe Content and increasing irradiation intensity could promote the catalytic performance of Fe alginate gel beads.
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preparation and photocatalytic performance of Fe iii amidoximated pan fiber complex for oxidative degradation of azo dye under visible light irradiation
Science of The Total Environment, 2010Co-Authors: Yongchun Dong, Fang DuAbstract:Abstract Polyacrylonitrile (PAN) fiber was modified with hydroxylamine hydrochloride to introduce amidoxime groups onto the fiber surface. These amidoxime groups were used to react with Fe (III) ions to prepare Fe (III)-amidoximated PAN fiber complex, which was characterized using SEM, XRD, FTIR, XPS, DMA, and DRS respectively. Then the photocatalytic activity of Fe–AO–PAN was evaluated in the degradation of a typical azo dye, C. I. Reactive Red 195 in the presence of H 2 O 2 under visible light irradiation. Moreover, the efFect of the Fe Content of Fe–AO–PAN on dye degradation was also investigated. The results indicated that Fe (III) ions can crosslink between the modified PAN fiber chains by the coordination of Fe (III) ions with the amino nitrogen atoms and hydroxyl oxygen atoms of the amidoximation groups to form Fe (III)-amidoximated PAN fiber complex, and the Fe Content of which is mainly determined by Fe (III) ions and amidoximation groups. Fe (III)-amidoximated PAN fiber complex is found to be activated in the visible light region. Moreover, Fe (III)-amidoximated PAN fiber complex shows the catalytic activity for dye degradation by H 2 O 2 at pH = 6.0 in the dark, and can be significantly enhanced by increasing light irradiation and Fe Content, therefore, it can be used as a new heterogeneous Fenton photocatalyst for the efFective decomposition of the dye in water. In addition, ESR spectra confirm that Fe (III)-amidoximated PAN fiber complex can generate more OH radicals from H 2 O 2 under visible light irradiation, leading to dye degradation. A possible mechanism of photocatalysis is proposed.
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preparation and photocatalytic performance of Fe iii amidoximated pan fiber complex for oxidative degradation of azo dye under visible light irradiation
Science of The Total Environment, 2010Co-Authors: Yongchun Dong, Zhenbang Han, Chunyan LiuAbstract:Abstract Polyacrylonitrile (PAN) fiber was modified with hydroxylamine hydrochloride to introduce amidoxime groups onto the fiber surface. These amidoxime groups were used to react with Fe (III) ions to prepare Fe (III)-amidoximated PAN fiber complex, which was characterized using SEM, XRD, FTIR, XPS, DMA, and DRS respectively. Then the photocatalytic activity of Fe–AO–PAN was evaluated in the degradation of a typical azo dye, C. I. Reactive Red 195 in the presence of H 2 O 2 under visible light irradiation. Moreover, the efFect of the Fe Content of Fe–AO–PAN on dye degradation was also investigated. The results indicated that Fe (III) ions can crosslink between the modified PAN fiber chains by the coordination of Fe (III) ions with the amino nitrogen atoms and hydroxyl oxygen atoms of the amidoximation groups to form Fe (III)-amidoximated PAN fiber complex, and the Fe Content of which is mainly determined by Fe (III) ions and amidoximation groups. Fe (III)-amidoximated PAN fiber complex is found to be activated in the visible light region. Moreover, Fe (III)-amidoximated PAN fiber complex shows the catalytic activity for dye degradation by H 2 O 2 at pH = 6.0 in the dark, and can be significantly enhanced by increasing light irradiation and Fe Content, therefore, it can be used as a new heterogeneous Fenton photocatalyst for the efFective decomposition of the dye in water. In addition, ESR spectra confirm that Fe (III)-amidoximated PAN fiber complex can generate more OH radicals from H 2 O 2 under visible light irradiation, leading to dye degradation. A possible mechanism of photocatalysis is proposed.
J W Chai - One of the best experts on this subject based on the ideXlab platform.
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deposition of iron containing amorphous carbon films by filtered cathodic vacuum arc technique
Diamond and Related Materials, 2001Co-Authors: J S Chen, Gang Chen, Yingtao Li, J W ChaiAbstract:Ž. Iron containing amorphous carbon a-C:Fe films have been deposited with an Fegraphite composite target with difFerent Fe Ž. Ž . Content by filtered cathodic vacuum arc FCVA technique. X-Ray induced photoelectron spectroscopy XPS was used to analyze the Fe Content in the films. Micro-Raman spectroscopy was employed to characterize the structural changes of a-C:Fe films. The properties of the a-C:Fe films such as the intrinsic stress, morphology and roughness investigated by the profiler, atomic force Ž. microscope AFM . The XPS results show that there exists small amount of oxygen in the form of FeO in the films and the Fe fraction in the films is always larger than that in the target. Compared with pure amorphous carbon films the intrinsic stress was efFectively reduced by incorporating Fe into the films, and decreases with increasing Fe Content. As increasing the Fe Content, the clusters in the films become finer and the roughness increases The studies of Raman spectra show that the positions of G peak and D peak shift to low and high wavenumbers, respectively, and the ratio of the intensity of D and G peaks increases with an increase in Fe Content, that suggests that the sp 2 -bonded carbon and the size of the sp 2 -bonded cluster increases with an increase in the Fe Content. 2001 Elsevier Science B.V. All rights reserved.
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deposition of iron containing amorphous carbon films by filtered cathodic vacuum arc technique
Diamond and Related Materials, 2001Co-Authors: J S Chen, Gang Chen, Shu Ping Lau, Zhili Sun, B K Tay, J W ChaiAbstract:Ž. Iron containing amorphous carbon a-C:Fe films have been deposited with an Fegraphite composite target with difFerent Fe Ž. Ž . Content by filtered cathodic vacuum arc FCVA technique. X-Ray induced photoelectron spectroscopy XPS was used to analyze the Fe Content in the films. Micro-Raman spectroscopy was employed to characterize the structural changes of a-C:Fe films. The properties of the a-C:Fe films such as the intrinsic stress, morphology and roughness investigated by the profiler, atomic force Ž. microscope AFM . The XPS results show that there exists small amount of oxygen in the form of FeO in the films and the Fe fraction in the films is always larger than that in the target. Compared with pure amorphous carbon films the intrinsic stress was efFectively reduced by incorporating Fe into the films, and decreases with increasing Fe Content. As increasing the Fe Content, the clusters in the films become finer and the roughness increases The studies of Raman spectra show that the positions of G peak and D peak shift to low and high wavenumbers, respectively, and the ratio of the intensity of D and G peaks increases with an increase in Fe Content, that suggests that the sp 2 -bonded carbon and the size of the sp 2 -bonded cluster increases with an increase in the Fe Content. 2001 Elsevier Science B.V. All rights reserved.
Fang Du - One of the best experts on this subject based on the ideXlab platform.
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preparation and photocatalytic performance of Fe iii amidoximated pan fiber complex for oxidative degradation of azo dye under visible light irradiation
Science of The Total Environment, 2010Co-Authors: Yongchun Dong, Fang DuAbstract:Abstract Polyacrylonitrile (PAN) fiber was modified with hydroxylamine hydrochloride to introduce amidoxime groups onto the fiber surface. These amidoxime groups were used to react with Fe (III) ions to prepare Fe (III)-amidoximated PAN fiber complex, which was characterized using SEM, XRD, FTIR, XPS, DMA, and DRS respectively. Then the photocatalytic activity of Fe–AO–PAN was evaluated in the degradation of a typical azo dye, C. I. Reactive Red 195 in the presence of H 2 O 2 under visible light irradiation. Moreover, the efFect of the Fe Content of Fe–AO–PAN on dye degradation was also investigated. The results indicated that Fe (III) ions can crosslink between the modified PAN fiber chains by the coordination of Fe (III) ions with the amino nitrogen atoms and hydroxyl oxygen atoms of the amidoximation groups to form Fe (III)-amidoximated PAN fiber complex, and the Fe Content of which is mainly determined by Fe (III) ions and amidoximation groups. Fe (III)-amidoximated PAN fiber complex is found to be activated in the visible light region. Moreover, Fe (III)-amidoximated PAN fiber complex shows the catalytic activity for dye degradation by H 2 O 2 at pH = 6.0 in the dark, and can be significantly enhanced by increasing light irradiation and Fe Content, therefore, it can be used as a new heterogeneous Fenton photocatalyst for the efFective decomposition of the dye in water. In addition, ESR spectra confirm that Fe (III)-amidoximated PAN fiber complex can generate more OH radicals from H 2 O 2 under visible light irradiation, leading to dye degradation. A possible mechanism of photocatalysis is proposed.
Chunyan Liu - One of the best experts on this subject based on the ideXlab platform.
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preparation and photocatalytic performance of Fe iii amidoximated pan fiber complex for oxidative degradation of azo dye under visible light irradiation
Science of The Total Environment, 2010Co-Authors: Yongchun Dong, Zhenbang Han, Chunyan LiuAbstract:Abstract Polyacrylonitrile (PAN) fiber was modified with hydroxylamine hydrochloride to introduce amidoxime groups onto the fiber surface. These amidoxime groups were used to react with Fe (III) ions to prepare Fe (III)-amidoximated PAN fiber complex, which was characterized using SEM, XRD, FTIR, XPS, DMA, and DRS respectively. Then the photocatalytic activity of Fe–AO–PAN was evaluated in the degradation of a typical azo dye, C. I. Reactive Red 195 in the presence of H 2 O 2 under visible light irradiation. Moreover, the efFect of the Fe Content of Fe–AO–PAN on dye degradation was also investigated. The results indicated that Fe (III) ions can crosslink between the modified PAN fiber chains by the coordination of Fe (III) ions with the amino nitrogen atoms and hydroxyl oxygen atoms of the amidoximation groups to form Fe (III)-amidoximated PAN fiber complex, and the Fe Content of which is mainly determined by Fe (III) ions and amidoximation groups. Fe (III)-amidoximated PAN fiber complex is found to be activated in the visible light region. Moreover, Fe (III)-amidoximated PAN fiber complex shows the catalytic activity for dye degradation by H 2 O 2 at pH = 6.0 in the dark, and can be significantly enhanced by increasing light irradiation and Fe Content, therefore, it can be used as a new heterogeneous Fenton photocatalyst for the efFective decomposition of the dye in water. In addition, ESR spectra confirm that Fe (III)-amidoximated PAN fiber complex can generate more OH radicals from H 2 O 2 under visible light irradiation, leading to dye degradation. A possible mechanism of photocatalysis is proposed.
Akihiro Makino - One of the best experts on this subject based on the ideXlab platform.
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Fe rich soft magnetic Fesibpcu hetero amorphous alloys with high saturation magnetization
Materials Transactions, 2009Co-Authors: Takeshi Kubota, Kunio Yubuta, Liying Cui, Akihiro MakinoAbstract:Magnetic properties are perhaps the most remarkable and unique properties of Fe-based amorphous alloys. To obtain high saturation magnetization, high Fe Content is preFerred. However, there is a strict upper limit of Fe Content for the formation of a single amorphous structure with good magnetic softness. Fe-based amorphous alloys with high Fe Content over the limit have an as-quenched structure consisting of coarse � -Fe grains in an amorphous matrix, which inevitably results in inFerior magnetic softness. We have studied the efFect of P and/or Cu additions on the microstructure of Fe-based amorphous alloys with high Fe Content. The � -Fe grain size and the coercivity (Hc) decrease by the simultaneously adding P and Cu. The Fe-rich FeSiBPCu alloys with the optimized composition have an extremely small � -Fe-like phase of about 3 nm or smaller in a diameter, exhibits the higher Js of about 1.67 T than that of the typical Fe-based amorphous alloy and show the low coercivity (Hc) of about 4 Am � 1 in an as-quenched state. [doi:10.2320/matertrans.ME200831]
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soft magnetic Fesibpcu heteroamorphous alloys with high Fe Content
Journal of Applied Physics, 2009Co-Authors: Akihiro Makino, Kunio Yubuta, Takeshi KubotaAbstract:Fe–Si–B amorphous alloys with less than 80 at. % Fe are now in practical use because of their excellent magnetic softness and rather high magnetization (Js) basically owing to the lack of intrinsic magnetic anisotropy and the high Fe Content, respectively. A strict upper limit of the Fe Content (about 80 at. %) for the formation of a single amorphous phase with good magnetic softness hinders the improvement in Js of the Fe-based amorphous alloys. The alloys with the high Fe Content exceeding the limit commonly have the as-quenched structure consisting of coarse α-Fe grains in an amorphous matrix, which inevitably results in inFerior magnetic softness. The simultaneous addition of proper amounts of P and Cu is found to be significantly efFective in decreasing the grain size of α-Fe phase, formed in an amorphous matrix in the as-quenched Fe82Si9B9 amorphous alloys with high Fe Content exceeding the limit. Fe-rich Fe81.7Si9B7P2Cu0.3 heteroamorphous alloy with an as-quenched structure consisting of extremely ...
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Fesibp bulk metallic glasses with high magnetization and excellent magnetic softness
Journal of Magnetism and Magnetic Materials, 2008Co-Authors: Akihiro Makino, Takeshi Kubota, Chuntao Chang, Masahiro Makabe, Akihisa InoueAbstract:Abstract Fe-based amorphous alloy ribbons are one of the major soft magnetic materials, because of their superior magnetic properties such as the relatively high saturation magnetization (Js) of 1.5–1.6 T and good magnetic softness. However, the preparation of the ordinary amorphous magnetic alloys requires cooling rates higher than 104 K/s due to the low glass-forming ability (GFA) and thus restricts the material outer shape. Recently, Fe-metalloid-based bulk metallic glasses (BMGs) containing glass-forming elements such as Al, Ga, Nb, Mo, Y and so forth have been developed. These alloys have high GFA, leading to the formation of BMG rod with diameters of mm-order. However, the glass-forming metal elements in BMGs result in a remarkable decrease in magnetization. Basically, Js depends on Fe Content; hence, high Js requires high Fe Content in the Fe-based amorphous alloys or BMGs. On the other hand, high GFA requires a large amount of glass-forming elements in the alloys, which results in lower Fe Content. Therefore, in substances, the coexistence of high Js and high GFA is difficult. Since this matter should be immensely important from academia to industry in the material field, a great deal of effort has been devoted; however, it has remained unsolved for many years. In this paper, we present a novel Fe-rich FeSiBP BMG with high Js of 1.51 T comparable to the ordinary Fe–Si–B amorphous alloy now in practical use as well as with high GFA leading to a rod-shaped specimen of 2.5 mm in diameter, obtained by Cu-mold casting in air.
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Fe metalloids bulk glassy alloys with high Fe Content and high glass forming ability
Journal of Materials Research, 2008Co-Authors: Akihiro Makino, Takeshi Kubota, Chuntao Chang, Masahiro Makabe, Akihisa InoueAbstract:The coexistence of high Fe Content and high glass-forming ability (GFA) has been earnestly desired from academia to industry. We report a novel Fe 76 Si 9 B 10 P 5 bulk metallic glass with an unusual combination of high magnetization of 1.51 T due to high Fe Content as well as high GFA leading to a glassy rod with a diameter of 2.5 mm despite not containing any glass-forming metal elements. This alloy composed of familiar and low-priced elements, also exhibiting very excellent magnetic softness, has a great advantage for engineering and industry, and thus should make a contribution to energy saving and conservation of earth’s resources and environment.
