Characterization and dielectric studies of hydrogen-beam-irradiated PDMS polymeric materials

Haifa A. Al‑Yousef,B. M. Alotaibi,A. Atta,M. M. Abdel‑Hamid 한국고분자학회 2023 Macromolecular Research Vol.31 No.8

In this work, PDMS films are treated with varying fluence of hydrogen ion beams (6 × 1017, 9 × 1017, and 12 × 1017 ions/cm2) for used in storage energy devices. XRD and FTIR were used to analyze the PDMS films. Furthermore, the SEM is employed to study the morphological alterations in treated PDMS films. Both XRD and FTIR result indicated that PDMS is chemically interacting after ion treatment. In addition, the dielectric parameters of PDMS films are measured using an LCR device in the frequencies 102–106 Hz. After PDMS exposed to 12 × 1017 ions/cm2, the dielectric constant of the PDMS increased from 23.4 to 44.8, and energy density increased from 1.01 × 10–4 to 1.92 × 10–4 J/m3, while the conductivity increased from 0.29 × 10–7 to 4.3 × 10–7 S/cm. Moreover, the real M′ decreased from 0.198 for PDMS to 0.165 for 6 × 1017 ions/cm2 and to 0.052 at 12 × 1017 ions/cm2, while the imaginary M″ is decreased from 0.205 to 0.155 for 6 × 1017 ions/cm2, and to 0.069 for 12 × 1017 ions/cm2. The studies indicated that the structure as well as electrical characteristics of the treated PDMS had been improved, which allowing being used these substances in different electronic instrumentations.

Low energy irradiation induced effects on the surface characteristics of polydimethylsiloxane polymeric films

B. M. Alotaibi,A. Atta,M. R. Atta,E. Abdeltwab,M. M. Abdel-Hamid 한국고분자학회 2023 Macromolecular Research Vol.31 No.1

This work attempts to modify the hydrophilic-adherence properties of polydimethylsiloxane (PDMS) by exposing to oxygen beam for used in painting, printing, and clothing applications. The structural and morphology changes of irradiated PDMS films are analyzed using XRD and SEM, respectively. The chemical functional group is investigated by Fourier infrared spectroscopy (FTIR). The contact angle for water is reduced from 81.38° to 42.50°, while the contact angle for diiodomethane is reduced from 63.20° to 25.40° by varying the irradiation time from 1.5 to 6 min. On the other hand, for water liquid, the adhesion work is enhanced from 82.75 to 125.5 mJ/m2, and for diiodomethane liquid, it’s increased from 73.70 to 96.68 mJ/m2. Moreover, the polar energy γsp is enhanced from 6.44 to 20.25 mJ/m2, while, the γsd is increased from 26.73 to 46.01 mJ/m2, and the total γst is increased from 33.18 to 66.26 mJ/m2 by enhancing exposing time 1.5–6 min. The improvement in the adhesion and surface energy of the irradiated PDMS films is due to oxygen ion beam induced decreasing in PDMS surface hydrophobicity. The experimental data show the surface morphology, structure and surface properties of treated PDMS are modified and depend closely on the oxygen beam irradiation time.

Clinical Utility of Chest Sonography in Chronic Obstructive Pulmonary Disease Patients Focusing on Diaphragmatic Measurements

Hend M. Esmaeel, M.B.B.S., M.D.,Kamal A. Atta, M.B.B.S., M.D.,Safiya Khalaf, M.B.B.S.,Doaa Gadallah, M.B.B.S., M.D. 대한결핵및호흡기학회 2024 Tuberculosis and Respiratory Diseases Vol.87 No.1

Background: There are many methods of evaluating diaphragmatic function, includingtrans-diaphragmatic pressure measurements, which are considered the key rule of diagnosis. We studied the clinical usefulness of chest ultrasonography in evaluating stablechronic obstructive pulmonary disease (COPD) patients and those in exacerbation,focusing on diaphragmatic measurements and their correlation with spirometry andother clinical parameters. Methods: In a prospective case-control study, we enrolled 100 COPD patients dividedinto 40 stable COPD patients and 60 patients with exacerbation. The analysis included20 age-matched controls. In addition to the clinical assessment of the study population,radiological evaluation included chest radiographs and chest computed tomography. Transthoracic ultrasonography (TUS) was performed for all included subjects. Results: Multiple A lines (more than 3) were more frequent in COPD exacerbation thanin stable patients, as was the case for B-lines. TUS significantly showed high specificity,negative predictive value, positive predictive value, and accuracy in detecting pleuraleffusion, consolidation, pneumothorax, and lung mass. Diaphragmatic measurementswere significantly lower among stable COPD subjects than healthy controls. Diaphragmaticthickness and excursion displayed a significant negative correlation with bodymass index and the dyspnea scale, and a positive correlation with spirometry measures. Patients in Global Initiative for Chronic Obstructive Lung Disease (GOLD) groupD showed lower diaphragmatic measurements (thickness and excursion). Conclusion: The TUS of COPD patients both in stable and exacerbated conditions andthe assessment of diaphragm excursion and thickness by TUS in COPD patients andtheir correlations to disease-related factors proved informative and paved the way forthe better management of COPD patients.

Correction: Nitrogen plasma synthesis of flexible supercapacitors based on reduced graphene oxide/aloe vera/carbon nanotubes nanocomposite

M. M. Atta,Hesham M. H. Zakaly,N. Almousa,A. M. Abdel Reheem,M. Madani,Usama.F. Kandil,A. M. A. Henaish,Eman O. Taha 한국탄소학회 2023 Carbon Letters Vol.33 No.7

Nitrogen plasma synthesis of flexible supercapacitors based on reduced graphene oxide/aloe vera/carbon nanotubes nanocomposite

M. M. Atta,Hesham M. H. Zakaly,N. Almousa,A. M. Abdel Reheem,M. Madani,Usama.F. Kandil,A. M. A. Henaish,Eman O. Taha 한국탄소학회 2023 Carbon Letters Vol.33 No.6

Flexible supercapacitors (FS) are ideal as power backups for upcoming stretchable electronics due to their high power density and good mechanical compliance. However, lacking technology for FS mass manufacturing is still a significant obstacle. The present study describes a novel method for preparing FS based on reduced graphene oxide (RGO) using the N+ plasma technique, in which N+ reduces graphene oxide on the surface of a cotton/polyester substrate. The effect of aloe vera (AV) as a natural reducing & capping agent and carbon nanotubes (CNT) as nanoconductors on the electrochemical performance of the electrodes is studied. FESEM and XPS were employed to investigate the electrodes' structural and chemical composition of electrodes. The galvanostatic charge–discharge curves of electrodes revealed the enhancement of the electrochemical activity of the as-prepared electrode upon additions of AV and CNT. The areal capacitance of the RGO, RGO/AV, and RGO/ AV/CNT supercapacitors at 5 mV/s was 511, 1244.5, and 1879 mF/cm2, respectively. The RGO electrode showed capacitive retention of 80.9% after 2000 cycles enhanced to 89.7% and 92% for RGO/AV and RGO/AV/CNT electrodes, respectively. The equivalent series resistance of the RGO electrode was 126.28 Ω, decreased to 56.62 and 40.06 Ω for RGO/AV and RGO/ AV/CNT electrodes, respectively.

Effect of nitrogen ions on the structural, optical, and thermal properties of polyvinyl alcohol/starch blend

Atta M.M.,Abdel Reheem A.M. 한국물리학회 2022 Current Applied Physics Vol.36 No.-

This work examines the properties of polyvinyl alcohol (PVA)/starch film containing glycerol as a plasticizer under exposure to different nitrogen ion fluence. The prepared PVA/starch blend was irradiated with ion fluence from 3 × 1017 to 12 × 1017 ions.cm− 2 . From FTIR, the ion beam irradiation attack and weakens the C–H bond in PVA/starch blend. From XRD findings, the crystallite size of the blend decreased at 3 × 1017 ions/cm2 while it increased at higher fluence up to 9 × 1017 ions/cm2 . This indicates the degradation of the blend at low ion fluence compared to crosslinking at high ion fluence. Also, the optical bandgap of the blend was decreased with an increase in ion fluence. Furthermore, the effect of N+ ions on some optical dispersion parameters is studied. The thermal stability of the PVA/starch blend shows a decrease in thermal stability upon irradiation with 3 × 1017 ions/cm2 compared to higher thermal stability at higher doses up to 9 × 1017 ions/cm2 .

Characterization of reactive amphiphilic montmorillonite nanogels and its application for removal of toxic cationic dye and heavy metals water pollutants

Ayman M. Atta,Hamad A. Al-Lohedan,Z.A. ALOthman,Ahmed A. Abdel-Khalek,Ahmed M. Tawfeek 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.31 No.-

The present work aims to reduce the water surface tension using dispersed organophilic clay minerals toincrease the adsorption water pollutants (organic and inorganic) into the clay galleries. Therefore,sodium montmorillonite (Na-MMT) was functionalized with amphphiles based on crosslinked nanogelpolymers of N-isopropylacrylamide (NIPAm), sodium 2-acrylamido-2-methylpropane sulfonate (Na-AMPS), acrylamide (AAm) and acrylamidopropyl)trimethylammonium chloride solution (APTAC) usingsurfactant free technique. The chemical interactions between nanogels and Na-MMT and their chemicalstructure were confirmed by FTIR analysis. The intercalation and exfoliation of Na-MMT were confirmedby wide-angle X-ray diffraction. The morphology of Na-MMT nanogel composites was investigated byTEM analysis. The adsorption capacities of the prepared Na-MMT nanogels for methylene blue dye,cobalt and nickel cations from water were investigated. The data indicated that the Na-MMT nanogelsreduced the surface tension of water and efficiently remove dye and metal ions from water.

Application of new amphiphilic ionic liquid based on ethoxylated octadecylammonium tosylate as demulsifier and petroleum crude oil spill dispersant

Ayman M. Atta,Hamad A. Al-Lohedan,Mahmood M.S. Abdullah,Shymaa M. ElSaeed 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.33 No.-

This work reports the synthesis and application of amphiphilic ionic liquid (IL) in the petroleum field. Theionic liquid was synthesized by etherification of octadecylamine with tetraethylene glycol followed byquaternization with p-toluene sulfonic acid. The chemical structure was confirmed by NMRspectroscopy. The surface activity, aggregation, adsorption, and the solubility of the ethoxylatedoctadecylammonium tosylate were investigated. The interfacial parameters between IL aqueoussolution and crude oil emulsions were determined from interfacial tension measurement. The resultsshowed the dependence of interfacial tension on the concentration, crude oil emulsion composition andchemical structure of the prepared amphiphiles. The mechanism of aggregation and adsorptionethoxylated octadecylammonium tosylate was proposed and confirmed at different interfaces. Thedemulsification and oil spill dispersion efficiencies were investigated at different amphiphileconcentrations. The performance of amphiphilic ILs revealed that their demulsification efficiencyreached 100% and the settling time required for efficient separation decreased with increment of watercontents of crude oil emulsions. Moreover, the prepared amphiphilic ILs achieved oil spill dispersionefficiency more than 80% at surfactant oil ratio (1:25).

Temperature induced delocalization of charge carriers and metallic phase in Co_0.6Sn_0.4Fe₂O₄ nanoparticles

ur Rahman, Atta,Rafiq, M. A.,Maaz, K.,Karim, S.,Oh Cho, Sung,Hasan, M. M. American Institute of Physics 2012 JOURNAL OF APPLIED PHYSICS - Vol.112 No.6

Synthesis, structural characterization, and optical properties of PVA/MnO2 materials for optoelectronics applications

Norah A. M. Alsaif,A. Atta,E. Abdeltwab,M. M. Abdel‑Hamid 한국고분자학회 2024 Macromolecular Research Vol.32 No.1

In this study, polyvinyl alcohol (PVA) was mixed with concentration of 5%, 7.5%, and 10% of manganese dioxide ( MnO2) to form PVA/MnO2 films using solution cast approach method. The X-ray diffraction (XRD) verified that the nanomaterials films were successfully fabricated. The scanning electron microscope (SEM) illustrates the uniform MnO2 dispersion within the PVA host matrix. Additionally, the influence of MnO2 on the optical properties is recorded. The refractive index (n0) is improved by adding MnO2, from 1.29 for PVA to 1.87 for PVA/5%MnO2 and 2.86 for PVA/10%MnO2. The PVA had a dispersion energy of 2.53 eV, while PVA with 5% MnO2 had 4.86 eV, PVA with 7.5% MnO2 had 5.74 eV, and PVA with 10%MnO2 had 7.12 eV. In addition, the oscillation energy E0 decreased from 3.79 for PVA to 1.94, 1.72, and 0.99 eV, respectively for PVA/5%MnO2, PVA/7.5%MnO2, and PVA/10%MnO2. It is evident from the data that the incorporation of MnO2 to the PVA polymer alters its optical properties. This proved the existence of strong interactions of PVA and MnO2 due to the modification of the PVA/MnO2 electronic structure. Moreover, the plasma frequency W p value increased from 0.79 × 1013 s− 1 for PVA to 2.06 × 1013 s− 1 for PVA/10%MnO2. These shifts in W p provided the polarization is modified for the PVA/MnO2. The results obtained in this study provide evidence of the advantages associated with the utilization of MnO2 nanoparticles as a filler of improved polymeric structures. These findings also propose the potential suitability of MnO2 nanoparticles for application in the field of optics and electronic devices.