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Uheida, Abdusalam
Publikasjoner (10 av 10) Visa alla publikasjoner
Sallam, A., Hemeda, S., Toprak, M., Muhammed, M., Hassan, M. & Uheida, A. (2019). CT Scanning and MATLAB Calculations for Preservation of Coptic Mural Paintings in Historic Egyptian Monasteries. Scientific Reports, 9, Article ID 3903.
Åpne denne publikasjonen i ny fane eller vindu >>CT Scanning and MATLAB Calculations for Preservation of Coptic Mural Paintings in Historic Egyptian Monasteries
Vise andre…
2019 (engelsk)Inngår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, artikkel-id 3903Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Investigations of Coptic mural paintings in historic churches and monasteries demand a deep understanding of the micro structure of the mural painting layers. The main objective of the present study is to study the efficiency of new avenues of computed X-ray tomography (CT Scan) and MATLAB in the analysis of Coptic mural paintings, either in the form of images or videos made to collect information about the physical characteristics of the material structure of the layers of mural paintings. These advanced techniques have been used in the investigation of samples of Coptic mural paintings dating back to the V-VIII century A.D, which have been collected from several locations in the Coptic monasteries in Upper Egypt. The application of CT-scanning is a powerful non-destructive tool for imaging and investigation which can be applied to the preservation of monuments made from many different materials. The second stage of research will be to characterize the materials through analytical techniques including XRD, XRF, EDX and FTIR to confirm the findings of CT scanning and to provide additional information concerning the materials used and their deterioration processes. This paper presents the results of the first pilot study in which CT scan and MATLAB have been utilized in combination for the non-destructive evaluation and investigation of Coptic mural paintings in Upper Egypt. The examinations have been carried out on mural painting samples from three important Coptic monasteries in Upper Egypt: the Qubbat Al Hawa Monastery in Aswan, the Saint Simeon Monastery in Aswan and the Saint Matthew the Potter Monastery in Luxor. This multi-stranded investigation has provided us with important information about the physical structure of the paintings, grains dimensions, grain texture, pore media characterization which include the micro porosity, BET and TPV, surface rendering, and calculation of the points in the surface through calculations completed using MATLAB. CT scanning assisted in the investigation and analyses of image surface details, and helped to visualize hidden micro structures that would otherwise be inaccessible due to over painting.

sted, utgiver, år, opplag, sider
NATURE PUBLISHING GROUP, 2019
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-247812 (URN)10.1038/s41598-019-40297-z (DOI)000460508600133 ()30846738 (PubMedID)2-s2.0-85062614465 (Scopus ID)
Merknad

QC 20190401

Tilgjengelig fra: 2019-04-01 Laget: 2019-04-01 Sist oppdatert: 2019-04-01bibliografisk kontrollert
Zohdi, Z., Hashemi, M., Uheida, A., Moein, M. M. & Abdel-Rehim, M. (2019). Graphene Oxide Tablets for Sample Preparation of Drugs in Biological Fluids: Determination of Omeprazole in Human Saliva for Liquid Chromatography Tandem Mass Spectrometry. Molecules, 24(7), Article ID 1191.
Åpne denne publikasjonen i ny fane eller vindu >>Graphene Oxide Tablets for Sample Preparation of Drugs in Biological Fluids: Determination of Omeprazole in Human Saliva for Liquid Chromatography Tandem Mass Spectrometry
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2019 (engelsk)Inngår i: Molecules, ISSN 1420-3049, E-ISSN 1420-3049, Vol. 24, nr 7, artikkel-id 1191Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

In this study, a novel sort of sample preparation sorbent was developed, by preparing thin layer graphene oxide tablets (GO-Tabs) utilizing a mixture of graphene oxide and polyethylene glycol on a polyethylene substrate. The GO-Tabs were used for extraction and concentration of omeprazole (OME) in human saliva samples. The determination of OME was carried out using liquid chromatography-tandem mass spectrometry (LC-MS/MS) under gradient LC conditions and in the positive ion mode (ESI+) with mass transitions of m/z 346.3 -> 198.0 for OME and m/z 369.98 -> 252.0 for the internal standard. Standard calibration for the saliva samples was in the range of 2.0-2000 nmol L-1. Limits of detection and quantification were 0.05 and 2.0 nmol L-1, respectively. Method validation showed good method accuracy and precision; the inter-day precision values ranged from 5.7 to 8.3 (%RSD), and the accuracy of determinations varied from -11.8% to 13.3% (% deviation from nominal values). The extraction recovery was 60%, and GO-Tabs could be re-used for more than ten extractions without deterioration in recovery. In this study, the determination of OME in real human saliva samples using GO-Tab extraction was validated.

sted, utgiver, år, opplag, sider
MDPI, 2019
Emneord
graphene oxide, omeprazole, liquid chromatography, tandem mass spectrometry, saliva, GO-Tabs
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-251343 (URN)10.3390/molecules24071191 (DOI)000464946300002 ()30934659 (PubMedID)2-s2.0-85063759590 (Scopus ID)
Merknad

QC 20190521

Tilgjengelig fra: 2019-05-21 Laget: 2019-05-21 Sist oppdatert: 2019-05-21bibliografisk kontrollert
Yohai, L., Giraldo Mejía, H., Procaccini, R., Pellice, S., Laxman Kunjali, K., Dutta, J. & Uheida, A. (2019). Nanocomposite functionalized membranes based on silica nanoparticles oss-linked to electrospun nanofibrous support for arsenic(v) sorption from contaminated underground water. RSC Advances, 9(15), 8280-8289
Åpne denne publikasjonen i ny fane eller vindu >>Nanocomposite functionalized membranes based on silica nanoparticles oss-linked to electrospun nanofibrous support for arsenic(v) sorption from contaminated underground water
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2019 (engelsk)Inngår i: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 9, nr 15, s. 8280-8289Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Nanocomposite functionalized membranes were synthesized using surface functionalized mesoporous silica nanoparticles (MCM-NH2 or MCM-PEI) cross-linked to a modified polyacrylonitrile (mPAN) nanofibrous substrate for the removal of 1 mg L-1 of As(V); a concentration much higher than what has been reported for underground water in Argentina. Adsorption studies were carried out in batch mode at pH 8 with nanoparticles in colloidal form, as well as the nanoparticles supported on the modified PAN membranes (mPAN/MCM-NH2 and mPAN/MCM-PEI). Results indicate a twenty-fold improvement in As(V) adsorption with supported nanoparticles (nanocomposite membranes) as opposed to their colloidal form. The adsorption efficiency could be further enhanced by modifying the nanocomposite membrane surface with Fe3+ (mPAN/MCM-NH2-Fe3+ and mPAN/MCM-PEI-Fe3+) which resulted in more than 95% arsenic being removed within the first 15 minutes and a specific arsenic adsorption capacity of 4.61 mg g(-1) and 5.89 mg g(-1) for mPAN/MCM-NH2-Fe3+ and mPAN/MCM-PEI-Fe3+ nanocomposite membranes, respectively. The adsorption characteristics were observed to follow a pseudo-first order behavior. The results suggest that the synthesized materials are excellent for quick and efficient reduction of As(V) concentrations below the WHO guidelines and show promise for future applications.

sted, utgiver, år, opplag, sider
Royal Society of Chemistry, 2019
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-248339 (URN)10.1039/c8ra09866b (DOI)000461445300017 ()2-s2.0-85063011404 (Scopus ID)
Merknad

QC 20190503

Tilgjengelig fra: 2019-05-03 Laget: 2019-05-03 Sist oppdatert: 2019-05-03bibliografisk kontrollert
Uheida, A., Mohamed, A., Belaqziz, M. & Nasser, W. S. (2019). Photocatalytic degradation of Ibuprofen, Naproxen, and Cetirizine using PAN-MWCNT nanofibers crosslinked TiO2-NH2 nanoparticles under visible light irradiation. Separation and Purification Technology, 212, 110-118
Åpne denne publikasjonen i ny fane eller vindu >>Photocatalytic degradation of Ibuprofen, Naproxen, and Cetirizine using PAN-MWCNT nanofibers crosslinked TiO2-NH2 nanoparticles under visible light irradiation
2019 (engelsk)Inngår i: Separation and Purification Technology, ISSN 1383-5866, E-ISSN 1873-3794, Vol. 212, s. 110-118Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

In this work the photocatalytic degradation of pharmaceuticals (Ibuprofen, Cetirizine, and Naproxen) was evaluated using surface modified TiO2 nanoparticles immobilized on polyacrylonitrile/multiwall carbon nanotubes composite nanofibers. The photocatalytic degradation was studied under visible light (0.1 W/cm(2)) irradiation. Comparatively, the photocatalytic degradation of pharmaceuticals using PAN-CNT/TiO2-NH2 composite nanofibers was much more efficient than with PAN/TiO2-NH2 composite nanofibers under visible light irradiation. The results obtained showed that the photocatalytic efficiency of the studied pharmaceuticals is pH dependent in which more than 99% degradation was obtained at pH 2. Complete degradation of IBP, CTZ, and NPX was achieved within 200, 50, and 90 min, respectively under visible light.

sted, utgiver, år, opplag, sider
ELSEVIER SCIENCE BV, 2019
Emneord
Pharmaceuticals, Photodegradation, Composite nanofibers, Visible light
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-244479 (URN)10.1016/j.seppur.2018.11.030 (DOI)000457814700013 ()2-s2.0-85056218684 (Scopus ID)
Merknad

QC 20190320

Tilgjengelig fra: 2019-03-20 Laget: 2019-03-20 Sist oppdatert: 2019-03-20bibliografisk kontrollert
Mohamed, A., Salama, A., Nasser, W. S. & Uheida, A. (2018). Photodegradation of Ibuprofen, Cetirizine, and Naproxen by PAN-MWCNT/TiO2-NH2 nanofiber membrane under UV light irradiation. Environmental Sciences Europe, 30, Article ID 47.
Åpne denne publikasjonen i ny fane eller vindu >>Photodegradation of Ibuprofen, Cetirizine, and Naproxen by PAN-MWCNT/TiO2-NH2 nanofiber membrane under UV light irradiation
2018 (engelsk)Inngår i: Environmental Sciences Europe, ISSN 2190-4707, E-ISSN 2190-4715, Vol. 30, artikkel-id 47Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Background: In this study, the photodegradation of three pharmaceuticals, namely Ibuprofen (IBP), Naproxen (NPX), and Cetirizine (CIZ) in aqueous media was investigated under UV irradiation. The photocatalyst used in this work consists of surface functionalized titanium dioxide (TiO2-NH2) nanoparticles grafted into Polyacrylonitrile (PAN)/multi-walled carbon nanotube composite nanofibers. Surface modification of the fabricated composite nanofibers was illustrated using XRD, FTIR, and SEM analyses. Results: Sets of experiments were performed to study the effect of pharmaceuticals initial concentration (5-50 mg/L), solution pH (2-9), and irradiation time on the degradation efficiency. The results demonstrated that more than 99% degradation efficiency was obtained for IBP, CIZ, and NPX within 120, 40, and 25 min, respectively. Conclusions: Comparatively, the photocatalytic degradation of pharmaceuticals using PAN-CNT/TiO2-NH2 composite nanofibers was much more efficient than with PAN/TiO2-NH2 composite nanofibers.

sted, utgiver, år, opplag, sider
SPRINGEROPEN, 2018
Emneord
Photocatalytic, Cetirizine, Naproxen, Ibuprofen, Composite nanofibers, UV-light
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-240348 (URN)10.1186/s12302-018-0177-6 (DOI)000452025200001 ()2-s2.0-85057786194 (Scopus ID)
Merknad

QC 20181217

Tilgjengelig fra: 2018-12-17 Laget: 2018-12-17 Sist oppdatert: 2018-12-17bibliografisk kontrollert
Yazdi, M. G., Ivanic, M., Mohamed, A. & Uheida, A. (2018). Surface modified composite nanofibers for the removal of indigo carmine dye from polluted water. RSC Advances, 8(43), 24588-24598
Åpne denne publikasjonen i ny fane eller vindu >>Surface modified composite nanofibers for the removal of indigo carmine dye from polluted water
2018 (engelsk)Inngår i: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 8, nr 43, s. 24588-24598Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Surface coated magnetite nanoparticles (Fe3O4 NPs) with 3-mercaptopropionic acid were immobilized on amidoximated polyacrilonitrile (APAN) nanofibers using electrospinning followed by crosslinking. The prepared composite nanofibers were characterized with Scanning Electron Microscopy (SEM), and Fourier Transform Infrared analysis (FTIR). The composite nanofiber was evaluated for the removal of indigo carmine dye from aqueous solutions. The effects of contact time, initial dye concentration, solution pH and adsorption equilibrium isotherms were studied. The adsorption of indigo carmine was found to be greatly affected by solution pH. The maximum loading capacity was determined to be 154.5 mg g(-1) at pH = 5. The experimental kinetic data were fitted well using a pseudo-first order model. The adsorption isotherm studies showed that the adsorption of indigo carmine fits well with the Langmuir model. The reuse of the composite nanofiber was also investigated in which more than 90% of indigo carmine was recovered in 5 min. The results of stability studies showed that the adsorption efficiency can remain almost constant (90%) after five consecutive adsorption/desorption cycles.

sted, utgiver, år, opplag, sider
Royal Society of Chemistry, 2018
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-233304 (URN)10.1039/c8ra02463d (DOI)000440243600055 ()2-s2.0-85049838997 (Scopus ID)
Forskningsfinansiär
EU, FP7, Seventh Framework Programme
Merknad

QC 20180816

Tilgjengelig fra: 2018-08-16 Laget: 2018-08-16 Sist oppdatert: 2018-08-16bibliografisk kontrollert
Mohamed, A., Yousef, S., Ali Abdelnaby, M., Osman, T. A., Hamawandi, B., Toprak, M. S., . . . Uheida, A. (2017). Photocatalytic degradation of organic dyes and enhanced mechanical properties of PAN/CNTs composite nanofibers. Separation and Purification Technology, 182, 219-223
Åpne denne publikasjonen i ny fane eller vindu >>Photocatalytic degradation of organic dyes and enhanced mechanical properties of PAN/CNTs composite nanofibers
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2017 (engelsk)Inngår i: Separation and Purification Technology, ISSN 1383-5866, E-ISSN 1873-3794, Vol. 182, s. 219-223Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

This work describes the enhanced mechanical properties of the composite nanofibers and the photodegradation of two organic dyes using PAN/CNTs under UV irradiation at different volume concentration (0.05, 0.1, 0.2, and 0.3 wt.%). The composite nanofibers was performed with polyacrylonitrile (PAN), and carbon nanotubes (CNTs) by electrospinning process. The composite nanofibers structure and morphology is characterized by XRD, FTIR, SEM, and TEM. The result indicates that with increasing CNTs content, the mechanical properties of the composite nanofibers was enhanced, and became more elastic, and the elastic modulus increased drastically. The results of mechanical properties exhibit improvements in tensile strengths, and elastic modulus by 38% and 84% respectively, at only 0.05 wt.% CNTs. Moreover, photocatalytic degradation performance in short time and low power intensity was achieved comparison to earlier reports.

sted, utgiver, år, opplag, sider
Elsevier, 2017
Emneord
Composite nanofibers, Mechanical properties, Photodegradation, Carbon, Carbon nanotubes, Elastic moduli, Irradiation, Tensile strength, Yarn, Electrospinning process, Organic dye, Photo catalytic degradation, Polyacrylonitrile (PAN), Structure and morphology, UV irradiation, Volume concentration, Nanofibers
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-207443 (URN)10.1016/j.seppur.2017.03.051 (DOI)000401393700025 ()2-s2.0-85016937303 (Scopus ID)
Merknad

QC 20170523

Tilgjengelig fra: 2017-05-23 Laget: 2017-05-23 Sist oppdatert: 2017-06-14bibliografisk kontrollert
Ashour, R. M., Abdelhamid, H. N., Abdel-Magied, A. F., Abdel-Khalek, A. A., Ali, M. M., Uheida, A., . . . Dutta, J. (2017). Rare Earth Ions Adsorption onto Graphene Oxide Nanosheets. Solvent extraction and ion exchange, 35(2), 91-103
Åpne denne publikasjonen i ny fane eller vindu >>Rare Earth Ions Adsorption onto Graphene Oxide Nanosheets
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2017 (engelsk)Inngår i: Solvent extraction and ion exchange, ISSN 0736-6299, E-ISSN 1532-2262, Vol. 35, nr 2, s. 91-103Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Graphene oxide (GO) was synthesized and used as a coagulant of rare earth elements (REEs) from aqueous solution. Stability and adsorption capacities were exhibited for target REEs such as La(III), Nd(III), Gd(III), and Y(III). The parameters influencing the adsorption capacity of the target species including contact time, pH, initial concentration, and temperature were optimized. The adsorption kinetics and thermodynamics were studied. The method showed quantitative recovery (99%) upon desorption using HNO3 acid (0.1 M) after a short contact time (15 min).

sted, utgiver, år, opplag, sider
Taylor & Francis, 2017
Emneord
Adsorption, desorption, rare earth, graphene oxide
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-207923 (URN)10.1080/07366299.2017.1287509 (DOI)000400509800002 ()2-s2.0-85014556348 (Scopus ID)
Merknad

QC 20170529

Tilgjengelig fra: 2017-05-29 Laget: 2017-05-29 Sist oppdatert: 2017-05-29bibliografisk kontrollert
Mohamed, A., Osman, T. A., Toprak, M. S., Muhammed, M. & Uheida, A. (2017). Surface functionalized composite nanofibers for efficient removal of arsenic from aqueous solutions. Chemosphere, 180, 108-116
Åpne denne publikasjonen i ny fane eller vindu >>Surface functionalized composite nanofibers for efficient removal of arsenic from aqueous solutions
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2017 (engelsk)Inngår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 180, s. 108-116Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

A novel composites nanofiber was synthesized based on PAN-CNT/TiO2-NH2 nanofibers using electrospinning technique followed by chemical modification of TiO2 NPs. PAN-CNT/TiO2-NH2 nanofiber were characterized by XRD, FTIR, SEM, and TEM. The effects of various experimental parameters such as initial concentration, contact time, and solution pH on As removal were investigated. The maximum adsorption capacity at pH 2 for As(III) and As(V) is 251 mg/g and 249 mg/g, respectively, which is much higher than most of the reported adsorbents. The adsorption equilibrium reached within 20 and 60 min as the initial solution concentration increased from 10 to 100 mg/L, and the data fitted well using the linear and nonlinear pseudo first and second order model. Isotherm data fitted well to the linear and nonlinear Langmuir, Freundlich, and Redlich-Peterson isotherm adsorption model. Desorption results showed that the adsorption capacity can remain up to 70% after 5 times usage. This work provides a simple and an efficient method for removing arsenic from aqueous solution.

sted, utgiver, år, opplag, sider
Elsevier Ltd, 2017
Emneord
Arsenic adsorption, Composite nanofibers, Electrospinning, Isotherm, Kinetics
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-207283 (URN)10.1016/j.chemosphere.2017.04.011 (DOI)000401880500013 ()2-s2.0-85017101033 (Scopus ID)
Merknad

QC 20170619

Tilgjengelig fra: 2017-06-19 Laget: 2017-06-19 Sist oppdatert: 2017-06-19bibliografisk kontrollert
Mohamed, A., Osman, T. A., Toprak, M. S., Muhammed, M., Yilmaz, E. & Uheida, A. (2016). Visible light photocatalytic reduction of Cr(VI) by surface modified CNT/titanium dioxide composites nanofibers. Journal of Molecular Catalysis A: Chemical, 424, 45-53
Åpne denne publikasjonen i ny fane eller vindu >>Visible light photocatalytic reduction of Cr(VI) by surface modified CNT/titanium dioxide composites nanofibers
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2016 (engelsk)Inngår i: Journal of Molecular Catalysis A: Chemical, ISSN 1381-1169, E-ISSN 1873-314X, Vol. 424, s. 45-53Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

In this work we report a highly efficient photocatalytic reduction of Cr(VI) based on PAN-CNT/TiO2-NH2 composite nanofibers fabricated by using electrospinning technique followed by chemical crosslinking of surface modified TiO2 NPs functionalized with amino group. The structure and morphology of the fabricated composite nanofibers were characterized by FTIR, SEM, TEM, TGA, and XPS. The results indicate that the composite nanofibers possess excellent photoreduction performance for Cr(VI) under visible light (125 W) after 30 min, which is much faster than previous reports. The effects of various experimental parameters such as catalyst dose, irradiation time, initial concentration of Cr(VI), and pH on the photoreduction efficiency of Cr(VI) were investigated. The highest photoreduction efficiency of Cr (VI) was obtained at low acidity and low amount of TiO2/CNT photocatalyst. The kinetic experimental data was attained and fitted well with a pseudo-first-order model. The UV–vis spectrophotometer and XPS analyses proved that chromate Cr(VI) was reduced to Cr(III). In addition, it can be concluded that the addition of the phenol enhances the photocatalytic reduction of Cr(VI). Furthermore, the photoreduction mechanism has also been discussed. Finally, the fabricated composite nanofibers were found to be stable after at least five regeneration cycles.

sted, utgiver, år, opplag, sider
Elsevier, 2016
Emneord
Chromium (VI), Composite nanofibers, Photocatalytic reduction, Visible light, Chromium compounds, Crosslinking, Efficiency, Fabrication, Light, Nanofibers, Titanium dioxide, X ray photoelectron spectroscopy, Chemical cross-linking, Electrospinning techniques, Experimental parameters, Photoreduction mechanisms, Structure and morphology, Chromium
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-195184 (URN)10.1016/j.molcata.2016.08.010 (DOI)000386739300006 ()2-s2.0-84982123816 (Scopus ID)
Merknad

QC 20161118

Tilgjengelig fra: 2016-11-18 Laget: 2016-11-02 Sist oppdatert: 2017-11-29bibliografisk kontrollert
Organisasjoner