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A thermodynamic understanding of horizontal pores formation in anodized doped aluminum with alloying elements

Research Abstract
Although there is a plenty of work in many publications concerning three-dimensional (3D) pore formation by an anodization process, though no definitive conclusion has been given to the mechanism of its formation. Accordingly, the process of 3D architecture is still a subject of considerable debate. The aim of the present study is to extend the previous findings, bringing out the relationship between different components such as the thermodynamic role of the precipitations mechanism in dilute aluminum (Al) alloy at the alloy/oxide interface, film thickness, anodizing potential and the resulting porous anodic alumina (PAA) film morphology. Dislocation movement following Orowan mechanism and its role in enriching layer formation is connected for the first time in explaining the formation of the enriched layer. Consequently, the precise disruption of the 3D morphologies within the anodic films is developed. The distributions of copper (Cu) spices in the alloy as well as within the enriched layer on the alloy/oxide surface are carefully investigated and explained using different experimental techniques. In addition, the oxygen generation is explored. The present study is designed to reveal the influences of impurities on the PAA architecture. It has the advantage of being a direct explanation for the mechanism of the defect in the PAA and its incorporation into the anodic film throughout the anodic film. Moreover, a reliable explanation for current density oscillation is explored. That help to gain further understanding of this phenomenon o control PAA structure in thermodynamically similar alloys. Based on the present study, free Cu atoms in solid solution are swept driven by vacancies according to Orowan interface during anodization forming an enriched ~2 nm layer of Cu just beneath the anodic film. The Cu is not significantly incorporated into the anodic film before the formation of θ′ precipitates in a thick film; whereas of thickness500 nm, the Cu atom migrates outward forming patterned precipitates rest at the surface for the thin film. The concentration of θ′ precipitates is calculated and found ~9×1015m−3. Accordingly, the Cu incorporation into the anodic film and 3D structure mechanism are correctly explored.
Research Authors
A.M. Mebed; Alaa Abd-Elnaiem
Research Department
Research Journal
Journal of Electroanalytical Chemistry
Research Member
Research Pages
138-147
Research Publisher
Elsevier
Research Rank
1
Research Vol
829
Research Website
https://doi.org/10.1016/j.jelechem.2018.10.006
Research Year
2018

A thermodynamic understanding of horizontal pores formation in anodized doped aluminum with alloying elements

Research Abstract
Although there is a plenty of work in many publications concerning three-dimensional (3D) pore formation by an anodization process, though no definitive conclusion has been given to the mechanism of its formation. Accordingly, the process of 3D architecture is still a subject of considerable debate. The aim of the present study is to extend the previous findings, bringing out the relationship between different components such as the thermodynamic role of the precipitations mechanism in dilute aluminum (Al) alloy at the alloy/oxide interface, film thickness, anodizing potential and the resulting porous anodic alumina (PAA) film morphology. Dislocation movement following Orowan mechanism and its role in enriching layer formation is connected for the first time in explaining the formation of the enriched layer. Consequently, the precise disruption of the 3D morphologies within the anodic films is developed. The distributions of copper (Cu) spices in the alloy as well as within the enriched layer on the alloy/oxide surface are carefully investigated and explained using different experimental techniques. In addition, the oxygen generation is explored. The present study is designed to reveal the influences of impurities on the PAA architecture. It has the advantage of being a direct explanation for the mechanism of the defect in the PAA and its incorporation into the anodic film throughout the anodic film. Moreover, a reliable explanation for current density oscillation is explored. That help to gain further understanding of this phenomenon o control PAA structure in thermodynamically similar alloys. Based on the present study, free Cu atoms in solid solution are swept driven by vacancies according to Orowan interface during anodization forming an enriched ~2 nm layer of Cu just beneath the anodic film. The Cu is not significantly incorporated into the anodic film before the formation of θ′ precipitates in a thick film; whereas of thickness500 nm, the Cu atom migrates outward forming patterned precipitates rest at the surface for the thin film. The concentration of θ′ precipitates is calculated and found ~9×1015m−3. Accordingly, the Cu incorporation into the anodic film and 3D structure mechanism are correctly explored.
Research Authors
A.M. Mebed; Alaa Abd-Elnaiem
Research Department
Research Journal
Journal of Electroanalytical Chemistry
Research Pages
138-147
Research Publisher
Elsevier
Research Rank
1
Research Vol
829
Research Website
https://doi.org/10.1016/j.jelechem.2018.10.006
Research Year
2018

Morphology of anodic aluminum oxide anodized in a mixture of phosphoric acid and lithium phosphate monobasic

Research Abstract
High-purity aluminum thin films (500nmthick) were anodized in a mixture of phosphoric acid and lithium phosphate monobasic at a constant anodizing voltage (2.5 or 50V) to obtain different structures of porous alumina doped with lithium ions. The morphology of the formed porous alumina was obtained by scanning electron microscopy (SEM). A few characteristic parameters of porous alumina such as pore diameter, inter-pore distance, volume expansion and etching process were investigated. The results showed that porous alumina having irregular, high pore size and very thin walls were formed at low anodization voltage (2.5V). The resulting low anodizing rates also lead to the dissolution of alumina in the electrolyte. In contrast, conventional pore structures with volume expansion factor close to 1.4 were formed at high anodization voltage (50V). The presence of lithium in porous anodic alumina confirmed by Raman spectroscopy. The possible formation of porous alumina incorporated with lithium ions opens the way for various applications such as energy and sensor based on anodized Al as a matrix of the Li-composite electrolyte.
Research Authors
Alaa M. Abd-Elnaiem; M. Rashad
Research Department
Research Journal
Materials Research Express
Research Pages
016412
Research Publisher
IOPscience
Research Rank
1
Research Vol
6
Research Website
http://iopscience.iop.org/article/10.1088/2053-1591/aae32d/pdf
Research Year
2019

Morphology of anodic aluminum oxide anodized in a mixture of phosphoric acid and lithium phosphate monobasic

Research Abstract
High-purity aluminum thin films (500nmthick) were anodized in a mixture of phosphoric acid and lithium phosphate monobasic at a constant anodizing voltage (2.5 or 50V) to obtain different structures of porous alumina doped with lithium ions. The morphology of the formed porous alumina was obtained by scanning electron microscopy (SEM). A few characteristic parameters of porous alumina such as pore diameter, inter-pore distance, volume expansion and etching process were investigated. The results showed that porous alumina having irregular, high pore size and very thin walls were formed at low anodization voltage (2.5V). The resulting low anodizing rates also lead to the dissolution of alumina in the electrolyte. In contrast, conventional pore structures with volume expansion factor close to 1.4 were formed at high anodization voltage (50V). The presence of lithium in porous anodic alumina confirmed by Raman spectroscopy. The possible formation of porous alumina incorporated with lithium ions opens the way for various applications such as energy and sensor based on anodized Al as a matrix of the Li-composite electrolyte.
Research Authors
Alaa M. Abd-Elnaiem; M. Rashad
Research Department
Research Journal
Materials Research Express
Research Member
Research Pages
016412
Research Publisher
IOPscience
Research Rank
1
Research Vol
6
Research Website
http://iopscience.iop.org/article/10.1088/2053-1591/aae32d/pdf
Research Year
2019

Zinc oxide nanoparticles-mediated changes in ultrastructure and macromolecules of pomegranate callus cells

Research Abstract
The dramatic increase in the usage of nanoparticles (NPs) in a variety of applications extensively expanded the possibility regarding the release of NPs into our ecosystem. Pomegranate is a tropical and subtropical countries’ shrub, as offers food supplement and more pharmaceutical and medicinal applications. Here, we investigated the effects concerning different concentrations regarding each of ZnO NPs and its bulk on growth, uptake of Zn, potassium (K), phosphorus (P), proline, ascorbic acid, total phenolic compounds, total antioxidant, localization of Zn in callus cells by transmission electron microscope (TEM) and changes in macromolecules by Fourier transform infrared spectroscopy (FT-IR) in pomegranate (Punica granatum cv. Hegazy) callus. Growth parameters in callus exposure to high concentrations of ZnO (50–200 µg mL−1) were reduced. Different concentrations of ZnO NPs and bulk did not affect the content of K and P. In comparison according to control, uptake of Zn was increased in pomegranate callus exposed to both ZnO NPs and its bulk. Moreover, TEM images showed small cells with the tortuous cell wall, disintegrated cytoplasmic content and Zn deposition in the cell walls at low concentration of ZnO NPs. However, the high concentration of ZnO NPs showed a further Zn influx in the cytoplasm and attachment to the tonoplast. The FT-IR analysis confirmed variations in the peaks corresponding to the most macromolecules, phenolic compounds, lipids, proteins, carbohydrates, cellulose, and hemicellulose. From these results, we could consider the toxicity effects concerning ZnO NPs and its bulk.
Research Authors
Abeer A. Radi· Fatma A. Farghaly· Fatma A. Al‑Kahtany· Afaf M. Hamada
Research Journal
Plant Cell, Tissue and Organ Culture (PCTOC)
Research Pages
15
Research Publisher
Springer Nature
Research Rank
1
Research Vol
NULL
Research Website
https://doi.org/10.1007/s11240-018-1460-3
Research Year
2018

Zinc oxide nanoparticles-mediated changes in ultrastructure and macromolecules of pomegranate callus cells

Research Abstract
The dramatic increase in the usage of nanoparticles (NPs) in a variety of applications extensively expanded the possibility regarding the release of NPs into our ecosystem. Pomegranate is a tropical and subtropical countries’ shrub, as offers food supplement and more pharmaceutical and medicinal applications. Here, we investigated the effects concerning different concentrations regarding each of ZnO NPs and its bulk on growth, uptake of Zn, potassium (K), phosphorus (P), proline, ascorbic acid, total phenolic compounds, total antioxidant, localization of Zn in callus cells by transmission electron microscope (TEM) and changes in macromolecules by Fourier transform infrared spectroscopy (FT-IR) in pomegranate (Punica granatum cv. Hegazy) callus. Growth parameters in callus exposure to high concentrations of ZnO (50–200 µg mL−1) were reduced. Different concentrations of ZnO NPs and bulk did not affect the content of K and P. In comparison according to control, uptake of Zn was increased in pomegranate callus exposed to both ZnO NPs and its bulk. Moreover, TEM images showed small cells with the tortuous cell wall, disintegrated cytoplasmic content and Zn deposition in the cell walls at low concentration of ZnO NPs. However, the high concentration of ZnO NPs showed a further Zn influx in the cytoplasm and attachment to the tonoplast. The FT-IR analysis confirmed variations in the peaks corresponding to the most macromolecules, phenolic compounds, lipids, proteins, carbohydrates, cellulose, and hemicellulose. From these results, we could consider the toxicity effects concerning ZnO NPs and its bulk.
Research Authors
Abeer A. Radi· Fatma A. Farghaly· Fatma A. Al‑Kahtany· Afaf M. Hamada
Research Journal
Plant Cell, Tissue and Organ Culture (PCTOC)
Research Member
Research Pages
15
Research Publisher
Springer Nature
Research Rank
1
Research Vol
NULL
Research Website
https://doi.org/10.1007/s11240-018-1460-3
Research Year
2018

Zinc oxide nanoparticles-mediated changes in ultrastructure and macromolecules of pomegranate callus cells

Research Abstract
The dramatic increase in the usage of nanoparticles (NPs) in a variety of applications extensively expanded the possibility regarding the release of NPs into our ecosystem. Pomegranate is a tropical and subtropical countries’ shrub, as offers food supplement and more pharmaceutical and medicinal applications. Here, we investigated the effects concerning different concentrations regarding each of ZnO NPs and its bulk on growth, uptake of Zn, potassium (K), phosphorus (P), proline, ascorbic acid, total phenolic compounds, total antioxidant, localization of Zn in callus cells by transmission electron microscope (TEM) and changes in macromolecules by Fourier transform infrared spectroscopy (FT-IR) in pomegranate (Punica granatum cv. Hegazy) callus. Growth parameters in callus exposure to high concentrations of ZnO (50–200 µg mL−1) were reduced. Different concentrations of ZnO NPs and bulk did not affect the content of K and P. In comparison according to control, uptake of Zn was increased in pomegranate callus exposed to both ZnO NPs and its bulk. Moreover, TEM images showed small cells with the tortuous cell wall, disintegrated cytoplasmic content and Zn deposition in the cell walls at low concentration of ZnO NPs. However, the high concentration of ZnO NPs showed a further Zn influx in the cytoplasm and attachment to the tonoplast. The FT-IR analysis confirmed variations in the peaks corresponding to the most macromolecules, phenolic compounds, lipids, proteins, carbohydrates, cellulose, and hemicellulose. From these results, we could consider the toxicity effects concerning ZnO NPs and its bulk.
Research Authors
Abeer A. Radi· Fatma A. Farghaly· Fatma A. Al‑Kahtany· Afaf M. Hamada
Research Journal
Plant Cell, Tissue and Organ Culture (PCTOC)
Research Pages
15
Research Publisher
Springer Nature
Research Rank
1
Research Vol
NULL
Research Website
https://doi.org/10.1007/s11240-018-1460-3
Research Year
2018

On Soft Semi-open Sets and Soft Semi-Continuity in Fuzzifying Soft Topological Spaces

Research Abstract
NULL
Research Authors
Ramadhan A. Mohammed A, Tahir H. Ismaild, Ahmed A. Allam
Research Department
Research Journal
Accepted of Publication in Euroasian Journal of Science and Engineering

Research Pages
NULL
Research Publisher
NULL
Research Rank
1
Research Vol
Vol.4,No.1
Research Website
NULL
Research Year
2018
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