35 results on '"Ahmed M. Tawfeek"'
Search Results
2. Stereoselective synthesis and X-ray structure determination of novel 1,2-dihydroquinolinehydrazonopropanoate derivatives
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Hendawy N. Tawfeek, Ahmed M. Tawfeek, Stefan Bräse, Martin Nieger, and Essmat M. El-Sheref
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Aza-michael addition ,Hydrazono-hydrazides ,Stereoselective synthesis ,4-Hydrazinyl-quinolin-2(1H)-Ones ,Ethyl propiolate ,1,2-Dihydroquinolin-4-yl(hydrazono)propanoate and X-ray crystallography ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
A novel series of 1,2-dihydroquinolinhydrazonopropanoate have been synthesized via a convenient aza-Michael addition reaction between hydrazinylquinolinones and ethyl propiolate in ethanol under refluxing temperature. The structures for all obtained products were confirmed with FTIR, NMR spectrums, as well as mass spectrometry. In addition, the monoclinic structure for compounds 8a, 8c, and 8d was also confirmed via X-ray crystallography analyses. The E-configuration for the obtained products was confirmed form the X-ray analysis. On the other hand, the crystal packing shows that the intermolecular and hydrogen bonds between atoms are parallel to the bc plan.
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- 2024
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3. Effects of sand and gating architecture on the performance of foot valve lever casting components used in pump industries
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I. Rajkumar, N. Rajini, Suchart Siengchin, Sikiru Oluwarotimi Ismail, Faruq Mohammad, Hamad A. Al-Lohedan, Ahmed M. Tawfeek, and Zuheir A. Issa
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Sand types ,Gating designs ,Surface roughness ,Porosity ,Simulation ,Experiment ,Mining engineering. Metallurgy ,TN1-997 - Abstract
This work addresses manufacture, testing and simulation of foot valve lever (FVL) for monoblock pump industry, using a cost-effective casting design process. The impact of different types of sands, such as air-set, dry and sodium silicate as well as gating designs, namely H-, U- and O-type, were studied with respect to surface roughness and porosity. The mold pattern was produced using additive manufacturing (AM) technology. Both experimental and numerical investigations were performed on the temperature distribution of molten metal at random locations for the different gating configurations or designs, considering mold filling and solidification. It was evident from the experimental investigation that contribution of air-set sand and O-type gating architecture showed limited consistency effects. Importantly, gating architecture was the most influential parameter to determine all specified quality outcomes, independent of sand mold. An order of O
- Published
- 2021
- Full Text
- View/download PDF
4. In-Silico Mining of the Toxins Database (T3DB) towards Hunting Prospective Candidates as ABCB1 Inhibitors: Integrated Molecular Docking and Lipid Bilayer-Enhanced Molecular Dynamics Study
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Mahmoud A. A. Ibrahim, Khlood A. A. Abdeljawaad, Alaa H. M. Abdelrahman, Peter A. Sidhom, Ahmed M. Tawfeek, Gamal A. H. Mekhemer, Mohamed K. Abd El-Rahman, Eslam Dabbish, and Tamer Shoeib
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MDR ,ABCB1 transporter ,Toxin and Toxin-Target Database (T3DB) ,docking computations ,MD simulations ,Medicine ,Pharmacy and materia medica ,RS1-441 - Abstract
Multidrug resistance (MDR) is one of the most problematic issues in chemotherapeutic carcinoma therapy. The ABCB1 transporter, a drug efflux pump overexpressed in cancer cells, has been thoroughly investigated for its association with MDR. Thus, discovering ABCB1 inhibitors can reverse the MDR in cancer cells. In the current work, a molecular docking technique was utilized for hunting the most prospective ABCB1 inhibitors from the Toxin and Toxin-Target Database (T3DB). Based on the docking computations, the most promising T3DB compounds complexed with the ABCB1 transporter were subjected to molecular dynamics (MD) simulations over 100 ns. Utilizing the MM-GBSA approach, the corresponding binding affinities were computed. Compared to ZQU (calc. −49.8 kcal/mol), Emamectin B1a (T3D1043), Emamectin B1b (T3D1044), Vincristine (T3D4016), Vinblastine (T3D4017), and Vindesine (T3D2479) complexed with ABCB1 transporter demonstrated outstanding binding affinities with ΔGbinding values of −93.0, −92.6, −93.8, −92.2, and −90.8 kcal/mol, respectively. The structural and energetic investigations confirmed the constancy of the identified T3DB compounds complexed with the ABCB1 transporter during the 100 ns MD course. To mimic the physiological conditions, MD simulations were conducted for those identified inhibitors complexed with ABCB1 transporter in the presence of a POPC membrane. These findings revealed that Emamectin B1a, Emamectin B1b, Vincristine, Vinblastine, and Vindesine are promising ABCB1 inhibitors that can reverse the MDR. Therefore, subjecting those compounds to further in-vitro and in-vivo investigations is worthwhile.
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- 2023
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5. Prostatic artery embolization versus transurethral resection of the prostate in management of benign prostatic hyperplasia
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Ahmed Radwan, Ahmed Farouk, Ahmed Higazy, Younan R. Samir, Ahmed M. Tawfeek, and Mohamed A. Gamal
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Prostate ,LUTS ,Embolization ,TURP ,Urine retention ,IPSS ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Background: Transurethral resection of the prostate (TURP) is considered the gold standard surgical intervention for prostate size less than 80 g. Prostatic artery embolization (PAE) has been suggested as a minimally invasive interventional radiological procedure in the management of benign prostatic hyperplasia (BPH), especially by using the PErFecTED technique. We aim through our study to evaluate the efficacy and safety of PAE compared with those of monopolar transurethral resection of prostate (M-TURP) and bipolar transurethral resection of prostate (B-TURP) in treating lower urinary tract symptoms (LUTSs) secondary to BPH. Methods: We randomized 60 patients into 3 equal groups representing M-TURP, B-TURP, and PAE. Patients were followed up at 1 and 6 months postoperatively with regard to the International prostate symptom score (IPSS) score; uroflowmetry; prostate volume by transrectal ultrasound; and postvoid residual urine. Results: The mean operative time was 59, 68, and 89 minutes for the M-TURP group, the B-TURP group, and the PAE group, respectively; only one patient, who represented 5% of the M-TURP group and 1.7% of the whole study population, developed transurethral resection syndrome. Four patients of the PAE group complained of postembolization syndrome, which represented 20% of the cases. Only two patients in our study, both belonging to the PAE group, developed acute urinary retention after catheter removal, representing 10% of the PAE group and 3.33% of the whole study population. The improvement in the IPSS score, the average uroflowmetry (Q-average) score, postvoid residual urine, and prostate volume reduction was noted in all groups, with more statistically significant improvement in each of the M-TURP and the B-TURP groups than in the PAE group. Conclusion: PErFecTED technique is a novel way of embolization, with statistically significant improvement for patients complaining of LUTSs due to BPH in terms of improvement of IPSS, uroflowmetry, prostate size, and amount of postvoid residual urine, yet these results are still not comparable with either the results of M-TURP or B-TURP that still show more effective improvement.
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- 2020
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6. Synthesis of New Hybrid Structured Magnetite Crosslinked Poly Ionic Liquid for Efficient Removal of Coomassie Brilliant Blue R-250 Dye in Aqueous Medium
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Abdelrahman O. Ezzat, Ahmed M. Tawfeek, Jothi Ramalingam Rajabathar, and Hamad A. Al-Lohedan
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magnetic nanoparticles ,ionic dye ,water treatment ,4-vinylpyridine-co-maleicanhydride ,poly ionic liquid ,Organic chemistry ,QD241-441 - Abstract
In this work, new crosslinked pyridinium poly ionic liquid and its magnetite hybrid structured composite were prepared and applied to remove the toxic dye Coomassie Brilliant Blue (CBB-R250) from aqueous solutions. In this respect, vinyl pyridine, maleic anhydride, and dibromo nonane were used to prepare crosslinked quaternized vinyl pyridinium/maleic anhydride ionic liquid (CQVP-MA). Furthermore, a linear copolymer was prepared by the reaction of vinyl pyridine with bromo nonane followed by its copolymerization with maleic anhydride in order to use it as a capping agent for magnetite nanoparticles. The monodisperse MNPs were incorporated into the crosslinked PIL (CQVP-MA) by ultrasonication to prepare CQVP-MA/Fe3O4 composite to facilitate its recovery using an external magnetic field and enhance its adsorption capacity. The chemical structures, thermal stabilities, zeta potential, particle size, EDS, and SEM of the prepared CQVP-MA and CQVP-MA/Fe3O4 were investigated. Adsorption kinetics, isotherms, and mechanisms of CB-R250 elimination from aqueous solutions using CQVP-MA and CQVP-MA/Fe3O4 were also studied, and the results revealed that the pseudo second-order kinetic model and the Langmuir isotherm model were the most suitable to describe the CBB adsorption from an aqueous solution. The adsorption capacities of CQVP-MA and CQVP-MA/Fe3O4 were found to be 1040 and 1198, respectively, which are more than those for previously reported material in the literature with reasonable stability for five cycles.
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- 2022
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7. Magnetic Ionic Liquid Nanocatalyst to Improve Mechanical and Thermal Properties of Epoxy Nanocomposites
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Ayman M. Atta, Hamad A. Al-Lohedan, Ahmed M. Tawfeek, and Nourah I. Sabeela
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magnetite ,imidazolium ionic liquid ,epoxy ,curing ,dynamic mechanical ,thermal ,Chemistry ,QD1-999 - Abstract
New magnetic imidazolium ionic liquid (IIL) was synthesized to improve the curing, mechanical, and thermal characteristics of the epoxy/polyamine system. In this respect, 2-(4-minophenyl)-1.3-bis(triethoxysilyl)-1H-imidazol-3-ium acetate as IIL was synthesized and characterized by different spectroscopy tools. The IIL was used as capping to prepare Fe3O4 nanoparticles (NPs) as new Fe3O4-IIL NPs. The thermal stability, morphology, crystal lattice structures, and magnetic properties were evaluated to confirm the formation of uniform, thermal, stable, and superparamagnetic Fe3O4-IIL NPs. The prepared Fe3O4-IIL NPs were mixed with an epoxy/polyamine system to improve the curing, thermal, and mechanical properties of epoxy through chemical reactions. The dynamic mechanical analyzer and differential scanning calorimeter were used to investigate the flexibility and storage modulus of the cured epoxy/polyamine system in the absence and presence of Fe3O4-IIL NPs. The atomic force microscope and scanning electron microscope were used to evaluate the dispersion and embedding of Fe3O4-IIL NPs into epoxy matrix. The thermal, mechanical, and surface morphologies data confirmed that the incorporation of Fe3O4-IIL NPs using 3 wt. % during the curing of an epoxy/polyamine system produces superior epoxy films without cracks, holes, and NPs agglomeration.
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- 2020
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8. Hybrid Ionic Silver and Magnetite Microgels Nanocomposites for Efficient Removal of Methylene Blue
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Ayman M. Atta, Amany K. Gafer, Hamad A. Al-Lohedan, Mahmood M. S. Abdullah, Ahmed M. Tawfeek, and Abdelrahman O. Ezzat
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water purification ,cationic dye ,adsorbents ,fenton oxidation catalyst ,magnetite ,silver nanocomposites ,Organic chemistry ,QD241-441 - Abstract
The ionic crosslinked 2-acrylamido-2-methylpropane sulfonic acid-co-acrylic acid hydrogel, AMPS/AA and its Ag and Fe3O4 composites were synthesized using an in situ technique. The surface charge, particle sizes, morphology, and thermal stability of the prepared AMPS/AA-Ag and AMPS/AA-Fe3O4 composites were evaluated using different analytical techniques and their adsorption characteristics were evaluated to remove the methylene blue cationic dye, MB, from their aqueous solutions at optimum conditions. Also, the same monomers were used to synthesize AMPS/AA microgel and its Ag and Fe3O4 nanocomposites, which were synthesized using the same technique. The AMPS/AA-Fe3O4 nanocomposite was selected as conventional iron-supported catalyst due to the presence of both Fe(II) and Fe(III) species besides its magnetic properties that allow their easy, fast, and inexpensive separation from the aqueous solution. It was then evaluated as a heterogeneous catalyst for complete MB degradation from aqueous solution by heterogeneous Fenton oxidation. It achieved a high rate of degradation, degrading 100 mg L−1 of MB during a short time of 35 min as compared with the reported literature.
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- 2019
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9. Synthesis of New Magnetic Crosslinked Poly (Ionic Liquid) Nanocomposites for Fast Congo Red Removal from Industrial Wastewater
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Ayman M. Atta, Abdelrahman O. Ezzat, Yaser M. Moustafa, Nourah I. Sabeela, Ahmed M. Tawfeek, Hamad A. Al-Lohedan, and Ahmed I. Hashem
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magnetite ,cross-linking ,poly(ionic liquids) ,4-vinylpyridine-co-acrylamide ,adsorbents ,Chemistry ,QD1-999 - Abstract
Advanced materials reliant on cross-linked magnetic poly (ionic liquids) (PILs) have been widely utilized in environmental applications for water purification. The present work demonstrates our preparation of a new magnetic cross-linked PIL based on quaternized 4-vinyl-pyridine-co-acrylamide (QVP/AAm). The chemical composition, thermal stability, magnetic properties, morphology, particle sizes, and zeta potential of the magnetic QVP/AAm composites were investigated. Fast adsorption and desorption kinetics, high adsorption capacity, rapid magnetic separation, and the absence of secondary pollution in the adsorption process make QVP/AAm-Fe3O4 a highly effective adsorbent for the elimination of anionic acidic Congo red contaminants from industrial wastewater.
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- 2019
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10. Application of New Sodium Vinyl Sulfonate–co-2-Acrylamido-2-me[thylpropane Sulfonic Acid Sodium Salt-Magnetite Cryogel Nanocomposites for Fast Methylene Blue Removal from Industrial Waste Water
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Sami A. Al-Hussain, Ayman M. Atta, Hamad A. Al-Lohedan, Abdelrahman O. Ezzat, and Ahmed M. Tawfeek
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methylene blue ,water treatment ,magnetic nanomaterials ,cryogel ,nanocomposites ,Chemistry ,QD1-999 - Abstract
Inorganic nanoparticles based on magnetite were used to improve the mechanical, thermal, and magnetic properties of microporous cryogel polymer composites. Here we report the synthesis of microporous cryogel based on the crosslinked sodium vinyl sulfonate (Na-VS) and 2-acrylamido-2-methylpropane sulfonic acid sodium salt (Na-AMPS). The magnetite nanoparticles were incorporated into Na-VS/Na-AMPS cryogel networks either during its crosslinking polymerization or by the in-situ technique after its crosslinking. The morphology, particle sizes, thermal stability, and magnetite contents of Na-VS/Na-AMPS cryogel and its magnetite composite were investigated. The prepared Na-VS/Na-AMPS cryogel and its magnetite composite were used as adsorbents for methylene blue (MB) cationic dye using optimum conditions. The magnetite Na-VS/Na-AMPS cryogel composite prepared by in-situ technique achieved the best adsorption MB removal capacity for 7 cycles among the other adsorbents via chemical adsorption mechanism at room temperature.
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- 2018
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11. Synthesis and characterization of novel metal chalcogenide modified Ni-Co-MnO2 nanofibers rolled with graphene based visible light active catalyst for nitro phenol degradation
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Rajabathar, Jothi Ramalingam, Arunachalam, Prabhakarn, Issa, Zuheir A., and Ahmed M, Tawfeek
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- 2020
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12. One-Step Synthesis of New Amphiphilic Nonionic Surfactants Based on Alkylamine and Poly(ethylene glycol) Dimethacrylate for Demulsification of Arabian Heavy Crude Oil Emulsions
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Abdelrahman O. Ezzat, Hamad A. Al-Lohedan, Ahmed M. Tawfeek, and Noorah A. Faqihi
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General Chemical Engineering ,General Chemistry - Published
- 2023
13. Clinical and Urodynamic Findings Before and After Surgical Repair of Pelvic Organ Prolapse in Women With Lower Urinary Tract Symptoms. A Prospective Observational Study
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Ahmed M. Tawfeek, Tarek Osman, Hany Hamed Gad, Mohamed Elmoazen, Dana Osman, and Ahmed Emam
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Adult ,Urodynamics ,Urinary Incontinence ,Lower Urinary Tract Symptoms ,Urinary Incontinence, Stress ,Urology ,Urinary Bladder, Underactive ,Humans ,Female ,Prospective Studies ,Middle Aged ,Pelvic Organ Prolapse - Abstract
To investigate the association between urodynamic findings and lower urinary tract symptoms (LUTS) before and after surgical treatment of pelvic organ prolapse (POP).Seventy-four patients with stage II or more anterior POP associated with LUTS and eligible for surgical repair of POP were included in this prospective study. All cases had clinical evaluation and urodynamic testing (UDS) before and 6 months after surgical repair of POP.Mean age was 45 ± 9 years. Mean BMI was 28 ± 6 kg/mPatients had significant improvement in LUTS after POP surgery with or without an anti-incontinence procedure. Detrusor underactivity was associated with persistence of voiding LUTS. Meanwhile, preoperative DO and post-void residual urine volume were of limited prognostic value.
- Published
- 2022
14. Multi-dimensional structural footprint identification for the design of potential scaffolds targeting METTL3 in cancer treatment from natural compounds
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Abdul Rashid Issahaku, Samukelisiwe Minenhle Mncube, Clement Agoni, Samuel K. Kwofie, Mohamed Issa Alahmdi, Nader E. Abo-Dya, Peter A. Sidhom, Ahmed M. Tawfeek, Mahmoud A. A. Ibrahim, Namutula Mukelabai, Opeyemi Soremekun, and Mahmoud E. S. Soliman
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Inorganic Chemistry ,Computational Theory and Mathematics ,Organic Chemistry ,Physical and Theoretical Chemistry ,Catalysis ,Computer Science Applications - Published
- 2023
15. Immobilization of lanthanide doped aluminate phosphor onto recycled polyester toward the development of long‐persistent photoluminescence smart window
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Mohamed El‐Newehy, Hany El‐Hamshary, Meera Moydeen Abdulhameed, and Ahmed M. Tawfeek
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Luminescence ,Strontium ,Chemistry (miscellaneous) ,Polyesters ,Biophysics ,Hydrophobic and Hydrophilic Interactions ,Lanthanoid Series Elements - Abstract
Smart window can be defined as switchable material whose light transmission is altered upon exposure to light, voltage, or heat. However, smart windows are usually produced from expensive and breakable glass materials. Herein, transparent smart window with long-persistent phosphorescence, high optical transmittance, ultraviolet (UV) protection, rigid, high photostability and durability, an d superhydrophobicity was developed from recycled polyester (PET). Recycled polyester waste (RBW) was simply immobilized with different ratios of lanthanide-doped aluminate nanoparticles (LdAN) to provide a long-persistent phosphorescent polyester smart window (LdAN@PET) with an abili ty to persist emitting light for extended time periods. The solid-state high temperature technique was used to prepare lanthanide-doped aluminate (LdA) micro-scale powder. Then, the top-down technique was applied to afford the corresponding LdAN. Recycled shredded recycled polyester bottles were charged into a hot bath to provide a clear plastic shred bulk, which was then well-mixed with LdAN and drop-casted to provide long-persistent luminescent smart window. In order to improve the phosphor dispersion in the PET bulk, LdAN was synthesized in the nanoparticle form which was characterized utilizing transmission electron microscopy (TEM). For better preparation of translucent smart window of long-persistent phosphorescent polyester, LdAN must be homogeneously dispersed in the PET matrix without agglomeration. The morphology and chemical composition were studied by Fourier-transform infrared (FTIR) spectra), X-ray fluorescence (XRF) analysis, scanning electron microscopy (SEM), and energy-dispersion X-ray spectroscopy (EDX). In addition, spectral profiles of excitation and emission, and decay and lifetime were used to better understand the photoluminescence properties. The hardness properties were also investigated. The developed phosphorescent transparent polyester smart window demonstrated a color switch to intense green underneath UV irradiation and greenish-yellow under darkness as verified by CIELab color parameters. The afterglow polyester smart window showed an absorption wavelength at 365 nm and two phosphorescence intensities at 442 and 512 nm. An enhanced UV protection, photostability and hydrophobic activity were detected. The luminescent polyester substrates with lower LdAN ratios demonstrated rapid and reversible fluorescent photochromic activity beneath the UV light. The luminescent polyester substrates with higher LdAN contents displayed long-persistent phosphorescence afterglow. The current strategy can be simply applied for the production of smart windows, low thickness anti-counterfeiting films and warning signs.
- Published
- 2022
16. Effects of sand and gating architecture on the performance of foot valve lever casting components used in pump industries
- Author
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Zuheir A. Issa, Sikiru Oluwarotimi Ismail, I. Rajkumar, Ahmed M. Tawfeek, Nagarajan Rajini, Suchart Siengchin, Faruq Mohammad, and Hamad A. Al-Lohedan
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business.product_category ,Materials science ,Mechanical engineering ,Sodium silicate ,Gating ,medicine.disease_cause ,Biomaterials ,Experiment ,chemistry.chemical_compound ,Surface roughness ,Gating designs ,Mold ,medicine ,Porosity ,Lever ,Mining engineering. Metallurgy ,Sand types ,TN1-997 ,Metals and Alloys ,Surfaces, Coatings and Films ,chemistry ,Casting (metalworking) ,Ceramics and Composites ,Design process ,business ,Simulation - Abstract
This work addresses manufacture, testing and simulation of foot valve lever (FVL) for monoblock pump industry, using a cost-effective casting design process. The impact of different types of sands, such as air-set, dry and sodium silicate as well as gating designs, namely H-, U- and O-type, were studied with respect to surface roughness and porosity. The mold pattern was produced using additive manufacturing (AM) technology. Both experimental and numerical investigations were performed on the temperature distribution of molten metal at random locations for the different gating configurations or designs, considering mold filling and solidification. It was evident from the experimental investigation that contribution of air-set sand and O-type gating architecture showed limited consistency effects. Importantly, gating architecture was the most influential parameter to determine all specified quality outcomes, independent of sand mold. An order of O
- Published
- 2021
17. The effect of stone size on the results of extracorporeal shockwave lithotripsy versus semi-rigid ureteroscopic lithotripsy in the management of upper ureteric stones
- Author
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Mohamed G. Soliman, Shawky A. El-Abd, Tarik A. Gameel, Ahmed M. Tawfeek, Magdy A. El-Sabaa, Ahmed S. El-Abd, and Hasan H. El-Tatawy
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medicine.medical_specialty ,Extracorporeal shockwave lithotripsy ,business.industry ,Urology ,Medicine ,Ureteroscopic lithotripsy ,Stone size ,business ,Surgery - Abstract
To evaluate the role of stone size on the efficacy and safety of extracorporeal shockwave lithotripsy (ESWL) monotherapy vs ureteroscopy (URS) for managing upper ureteric stones.The study design was a randomised prospective study of a total cohort of 180 patients with upper ureteric single stones of 0.5-1.5 cm. Half of the patients were managed by ESWL monotherapy, while the other half underwent URS with stone fragmentation using an ultrasound lithotripter (URSL). The success rate, re-treatment rate, auxiliary procedure (AP) rate, efficacy quotient, and complications were compared between the two groups.After single URSL and ESWL procedures 70/90 (77.8%) and 35/90 (38.9%) of the stones were successfully cleared, respectively (Our present study supports that ESWL is recommended as a first-line non-invasive monotherapy for upper ureteric opaque stones of1 cm, while URSL is recommended as a first-line treatment for stones of1 cm. The results for URSL were superior with lower a re-treatment rate, rapid stone clearance in a very short time, and less radiation exposure. Therefore, stone size is an important factor for the final decision of the initial management of upper ureteric stones because it has a direct relation to the efficacy of ESWL, but it has no effect on the results of URSL.
- Published
- 2022
18. A computational approach to standardise prostatic resection interventions by virtual reconstruction
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Ahmad M I Mahmoud, Ehab N Mohamed, Ahmed M Tawfeek, and Amr Y Elbanhawy
- Published
- 2021
19. Modification of magnetite nanoparticles surface with multifunctional ionic liquids for coomassie brilliant blue R-250 dye removal from aqueous solutions
- Author
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Abdelrahman O. Ezzat, Ahmed M. Tawfeek, Faruq Mohammad, and Hamad A. Al-Lohedan
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Materials Chemistry ,Physical and Theoretical Chemistry ,Condensed Matter Physics ,Spectroscopy ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials - Published
- 2022
20. Magnetic Ionic Liquid Nanocatalyst to Improve Mechanical and Thermal Properties of Epoxy Nanocomposites
- Author
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Ahmed M. Tawfeek, Ayman M. Atta, Hamad A. Al-Lohedan, and Nourah I Sabeela
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Magnetic ionic liquid ,Materials science ,magnetite ,Scanning electron microscope ,General Chemical Engineering ,curing ,Epoxy ,Dynamic mechanical analysis ,Article ,epoxy ,thermal ,lcsh:Chemistry ,Differential scanning calorimetry ,lcsh:QD1-999 ,Chemical engineering ,imidazolium ionic liquid ,visual_art ,visual_art.visual_art_medium ,dynamic mechanical ,General Materials Science ,Thermal stability ,Curing (chemistry) ,Superparamagnetism - Abstract
New magnetic imidazolium ionic liquid (IIL) was synthesized to improve the curing, mechanical, and thermal characteristics of the epoxy/polyamine system. In this respect, 2-(4-minophenyl)-1.3-bis(triethoxysilyl)-1H-imidazol-3-ium acetate as IIL was synthesized and characterized by different spectroscopy tools. The IIL was used as capping to prepare Fe3O4 nanoparticles (NPs) as new Fe3O4-IIL NPs. The thermal stability, morphology, crystal lattice structures, and magnetic properties were evaluated to confirm the formation of uniform, thermal, stable, and superparamagnetic Fe3O4-IIL NPs. The prepared Fe3O4-IIL NPs were mixed with an epoxy/polyamine system to improve the curing, thermal, and mechanical properties of epoxy through chemical reactions. The dynamic mechanical analyzer and differential scanning calorimeter were used to investigate the flexibility and storage modulus of the cured epoxy/polyamine system in the absence and presence of Fe3O4-IIL NPs. The atomic force microscope and scanning electron microscope were used to evaluate the dispersion and embedding of Fe3O4-IIL NPs into epoxy matrix. The thermal, mechanical, and surface morphologies data confirmed that the incorporation of Fe3O4-IIL NPs using 3 wt. % during the curing of an epoxy/polyamine system produces superior epoxy films without cracks, holes, and NPs agglomeration.
- Published
- 2020
21. Synthesis and application of novel gemini pyridinium ionic liquids as demulsifiers for arabian heavy crude oil emulsions
- Author
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Ahmed M. Tawfeek, Abdelrahman O. Ezzat, and Hamad A. Al-Lohedan
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Ethylene oxide ,Chemistry ,Chloride ,Surface tension ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,Pulmonary surfactant ,Chemical engineering ,Ionic liquid ,medicine ,Heavy crude oil ,Pyridinium ,Solubility ,medicine.drug - Abstract
Ionic liquids (ILs) are environmentally friendly compounds and their gemini types exhibit high thermal stabilities and high surface and interfacial activity. The main objective of this work is to prepare, characterize and investigate the demulsification efficiency of two gemini pyridinium surfactant ILs. They were prepared by the introduction of long chain decanoyl chloride to aminopyridine followed by quaternization with two dichloro spacers containing different ethylene oxide units (DCDE and TEGDC) to form MEGPy and TEGPy ILs, respectively. The structure properties of the prepared demulsifiers were investigated using different spectral tools including 1HNMR and 13CNMR and DLS. Also, their solubility and surface activity were investigated to confirm their ability to reduce surface tension (ST) and interfacial tension (IFT). Gemini pyridinium IL with triethylene oxide spacer (TEGP) showed higher ability to reduce both ST and IFT than that with mono ethylene oxide spacer (MEGP). Thanks to the ability of both TEGPy and MEGPy surfactant IL to reduce ST and IFT, they were applied successfully as demulsifiers for W/O emulsions with different water percentages. Demulsification study indicated that both TEGPy and MEGPy were able to demusify W/O emulsions with high performance which reached to 100% at low concentrations (250 ppm) for some compositions with higher activity to TEGP IL than MEGPy surfactant.
- Published
- 2022
22. New crosslinked poly (ionic liquid) cryogels for fast removal of methylene blue from waste water
- Author
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Ayman M. Atta, Ahmed M. Tawfeek, Sami A. Al-Hussain, Abdelrahman O. Ezzat, Ahmed I. Hashem, and Hamad A. Al-Lohedan
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Polymers and Plastics ,General Chemical Engineering ,02 engineering and technology ,Sulfonic acid ,010402 general chemistry ,01 natural sciences ,Biochemistry ,chemistry.chemical_compound ,Adsorption ,Materials Chemistry ,medicine ,Environmental Chemistry ,Thermal stability ,Acrylic acid ,chemistry.chemical_classification ,Aqueous solution ,General Chemistry ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,chemistry ,Chemical engineering ,Triethanolamine ,Ionic liquid ,Radical initiator ,0210 nano-technology ,medicine.drug - Abstract
New crosslinked Poly(ionic liquids), PILs, cryogels based on 2-acrylamido- 2-methylpropane sulfonic acid, AMPS, were prepared and copolymerized with acrylic acid, acrylamide or 2-hydroxyethyl methacrylate in the presence of triethanolamine. The crosslinking copolymerization of AMPS were carried in the presence of water at cooling temperature in the presence of amoniumpersulfate, N,N, N′, N′ tetramethylethylenediamine and N , N ′-methylenebisacrylamide as radical initiator, activator and crosslinker, respectively. The chemical structures, surface morphologies of the PILs cryogels were investigated. The PILs cryogels showed high thermal stability and interconnected pores. The cryogels achieved high adsorption capacity as 1228 mg·g −1 for removal of MB from aqueous solution during contact times ranged from 5 to 10 min. New mechanism for chemisorption of MB with the active centers of PIL cryogels is proposed and elucidated.
- Published
- 2018
23. Preparation of pH Responsive Polystyrene and Polyvinyl Pyridine Nanospheres Stabilized by Mickering Microgel Emulsions
- Author
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Hamad A. Al-Lohedan, Ahmed M. Tawfeek, Abdelrahman O. Ezzat, Abdulaziz A Alobaidi, and Ayman M. Atta
- Subjects
chemistry.chemical_classification ,Materials science ,Cyclohexane ,Scanning electron microscope ,General Chemical Engineering ,Mickering emulsions ,polystyrene composites ,Sulfonic acid ,Article ,microgels ,chemistry.chemical_compound ,Dynamic light scattering ,Chemical engineering ,chemistry ,Emulsion ,Particle ,General Materials Science ,Surface charge ,Polystyrene ,poly(4-vinylpyridine) - Abstract
New pH-sensitive polystyrene, PS, and poly(4-vinylpyridine), P4-VP, nanospheres were prepared by using surfactant-free method based on soft microgels (Mickering emulsion). The formation of stable Mickering cyclohexane/water emulsions was investigated by using soft microgel particles of poly(acrylamide), PAAm, poly(2-acrylamido-2-methylpropane sulfonic acid), PAMPS, and sodium salt of PAMPS, PAMPS-Na, as stabilizers. The dynamic light scattering (DLS), optical microscopy, and scanning electron microscopy (SEM) were used to investigate the optimum conditions and effects of surrounding solutions on the microgels characteristics and their corresponding Mickering emulsions. The cyclohexane/water Mickering emulsions stabilized by softer and neutral charged microgels were considerably more stable under the same conditions. Furthermore, the stimuli-responsive properties of PAMPS microgel stabilized cyclohexane/water Mickering emulsions suggest the potential utility in the preparation of PS and P4-VP nanospheres. The effects of pH changes on the morphology, particle sizes, and surface charges of PS and P4-VP microgels were evaluated to prove the pH-sensitivity of the prepared nanospheres.
- Published
- 2019
24. In situpreparation of magnetic Fe3O4.Cu2O.Fe3O4/cryogel nanocomposite powder via a reduction-coprecipitation method as adsorbent for methylene blue water pollutant
- Author
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Ayman M. Atta, Ahmed M. Tawfeek, Mona A. Ahmed, and Hamad A. Al-Lohedan
- Subjects
Nanocomposite ,Materials science ,Polymers and Plastics ,Coprecipitation ,Organic Chemistry ,Nanoparticle ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Adsorption ,chemistry ,Materials Chemistry ,Water treatment ,Particle size ,0210 nano-technology ,Methylene blue ,Sodium sulfite ,Nuclear chemistry - Published
- 2018
25. In situpreparation of magnetite/cuprous oxide/poly(AMPS/NIPAm) for removal of methylene blue from waste water
- Author
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Abdelrhman O. Ezzat, Ahmed M. Tawfeek, Talal Al-Otabi, Sami A. Al-Hussain, Ayman M. Atta, and Hamad A. Al-Lohedan
- Subjects
Materials science ,Polymers and Plastics ,Organic Chemistry ,Oxide ,Nanoparticle ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Adsorption ,chemistry ,Chemical engineering ,Wastewater ,Materials Chemistry ,Water treatment ,Sewage treatment ,0210 nano-technology ,Methylene blue ,Magnetite - Published
- 2018
26. Assessment on hybrid jute/coir fibers reinforced polyester composite with hybrid fillers under different environmental conditions
- Author
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K. Ganesan, Zuheir A. Issa, Hamad A. Al-Lohedan, Nadir Ayrilmis, Sikiru Oluwarotimi Ismail, Daifallah M. Aldhayan, Faruq Mohammad, C. Kailasanathan, Ahmed M. Tawfeek, and Nagarajan Rajini
- Subjects
Polyester composite ,Materials science ,Moisture absorption ,General Materials Science ,Building and Construction ,Composite material ,Coir ,Civil and Structural Engineering - Abstract
© 2021 Elsevier Ltd. All rights reserved. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1016/j.conbuildmat.2021.124117
- Published
- 2021
27. Synthesis, characterization and optical properties of sulfur and fluorine doped ZnO nanostructures for visible light utilized catalysis
- Author
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K. Kombaiah, R. Jothi Ramalingam, Arun Kumar Shukla, J. Judith Vijaya, and Ahmed M. Tawfeek
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Materials science ,Photoluminescence ,Band gap ,Doping ,chemistry.chemical_element ,02 engineering and technology ,Zinc ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,Dye-sensitized solar cell ,chemistry ,Chemical engineering ,Fluorine ,Electrical and Electronic Engineering ,0210 nano-technology ,Spectroscopy ,Visible spectrum - Abstract
Zinc oxide and sulfur/fluorine doped ZnO with nanosphere structure are synthesized by facile low cost solid state route. The synthesized material was characterized using XRD (X-ray diffraction), FE-SEM (Field emission scanning electron microscopy), photoluminescence spectroscopy and electrical conductive gas sensor measurements. FE-SEM images are showing spherical aggregated particle morphology, in the case of Fluorine doped ZnO showing flaky pastry shapes and sulphur doped ZnO shows particle with aggregated morphology. DRS and absorbance spectra is utilized to calculate the band gap values of the respective sample. The as prepared materials shows efficient activity towards methylene blue dye degradation and in future it could be utilized in improved photo catalytic and dye sensitized solar cell applications.
- Published
- 2017
28. Catalytic conversion of polyols (sorbitol and xylitol) to hydrocarbons over hierarchical ZSM-5 zeolite catalysts in a fixed bed reactor
- Author
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Subramanian Sivasanker, Ahmed M. Tawfeek, R. Jothiramalingam, L. John Kennedy, C. Ragupathi, J. Judith Vijaya, S. Narayanan, T.M. Sankaranarayanan, and Hamad A. Al-Lohedan
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Atmospheric pressure ,010405 organic chemistry ,Fixed bed ,010402 general chemistry ,Xylitol ,01 natural sciences ,Substrate concentration ,Catalysis ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Organic chemistry ,Sorbitol ,Physical and Theoretical Chemistry ,ZSM-5 zeolite ,Space velocity - Abstract
The catalytic activity of hierarchical ZSM-5 zeolites was investigated in the polyols (sorbitol and xylitol) to hydrocarbons conversion in a fixed bed reactor under atmospheric pressure by altering different parameters. A lower sorbitol and xylitol conversion was achieved at the reaction temperature of 375 °C, whereas a higher value of 92.33 and 88.19% sorbitol conversion, 95.58 and 92.32% xylitol conversion was obtained when the reaction temperature was further elevated to 425 °C for ZSM-5-WS(28) and ZSM-5-WOS(28) catalysts. Other important parameters, such as substrate concentration, weight hourly space velocity (WHSV) and Si/Al ratio strongly influenced the polyols to hydrocarbons conversion reaction. The optimal conditions are substrate concentration (sorbitol/xylitol) of 15%, WHSV of 1.0 h−1, reaction temperature of 425 °C. In addition to that, the recycling performances of the ZSM-5 catalysts were carried out for four runs and the catalysts were showed better recycling performance and stability.
- Published
- 2017
29. Synthesis of New Magnetic Crosslinked Poly (Ionic Liquid) Nanocomposites for Fast Congo Red Removal from Industrial Wastewater
- Author
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Hamad A. Al-Lohedan, Nourah I Sabeela, Abdelrahman O. Ezzat, Yaser M. Moustafa, Ayman M. Atta, Ahmed I. Hashem, and Ahmed M. Tawfeek
- Subjects
Materials science ,Nanocomposite ,magnetite ,adsorbents ,General Chemical Engineering ,Magnetic separation ,equipment and supplies ,Article ,Congo red ,Industrial wastewater treatment ,lcsh:Chemistry ,chemistry.chemical_compound ,Adsorption ,poly(ionic liquids) ,Chemical engineering ,chemistry ,lcsh:QD1-999 ,Ionic liquid ,parasitic diseases ,Zeta potential ,General Materials Science ,Thermal stability ,human activities ,4-vinylpyridine-co-acrylamide ,cross-linking - Abstract
Advanced materials reliant on cross-linked magnetic poly (ionic liquids) (PILs) have been widely utilized in environmental applications for water purification. The present work demonstrates our preparation of a new magnetic cross-linked PIL based on quaternized 4-vinyl-pyridine-co-acrylamide (QVP/AAm). The chemical composition, thermal stability, magnetic properties, morphology, particle sizes, and zeta potential of the magnetic QVP/AAm composites were investigated. Fast adsorption and desorption kinetics, high adsorption capacity, rapid magnetic separation, and the absence of secondary pollution in the adsorption process make QVP/AAm-Fe3O4 a highly effective adsorbent for the elimination of anionic acidic Congo red contaminants from industrial wastewater.
- Published
- 2019
30. Application of New Sodium Vinyl Sulfonate–co-2-Acrylamido-2-me[thylpropane Sulfonic Acid Sodium Salt-Magnetite Cryogel Nanocomposites for Fast Methylene Blue Removal from Industrial Waste Water
- Author
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Ahmed M. Tawfeek, Hamad A. Al-Lohedan, Abdelrahman O. Ezzat, Ayman M. Atta, and Sami A. Al-Hussain
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cryogel ,Materials science ,General Chemical Engineering ,02 engineering and technology ,Sulfonic acid ,010402 general chemistry ,01 natural sciences ,Article ,lcsh:Chemistry ,chemistry.chemical_compound ,Adsorption ,nanocomposites ,General Materials Science ,Thermal stability ,Magnetite ,chemistry.chemical_classification ,Cationic polymerization ,Microporous material ,water treatment ,magnetic nanomaterials ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Sulfonate ,Chemical engineering ,chemistry ,Polymerization ,lcsh:QD1-999 ,methylene blue ,0210 nano-technology - Abstract
Inorganic nanoparticles based on magnetite were used to improve the mechanical, thermal, and magnetic properties of microporous cryogel polymer composites. Here we report the synthesis of microporous cryogel based on the crosslinked sodium vinyl sulfonate (Na-VS) and 2-acrylamido-2-methylpropane sulfonic acid sodium salt (Na-AMPS). The magnetite nanoparticles were incorporated into Na-VS/Na-AMPS cryogel networks either during its crosslinking polymerization or by the in-situ technique after its crosslinking. The morphology, particle sizes, thermal stability, and magnetite contents of Na-VS/Na-AMPS cryogel and its magnetite composite were investigated. The prepared Na-VS/Na-AMPS cryogel and its magnetite composite were used as adsorbents for methylene blue (MB) cationic dye using optimum conditions. The magnetite Na-VS/Na-AMPS cryogel composite prepared by in-situ technique achieved the best adsorption MB removal capacity for 7 cycles among the other adsorbents via chemical adsorption mechanism at room temperature.
- Published
- 2018
- Full Text
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31. Application of New Sodium Vinyl Sulfonate-co-2-Acrylamido-2-methylpropane Sulfonic Acid Sodium Salt—Magnetite Cryogel Nanocomposites for Fast Methylene Blue Removal from Industrial Waste Water
- Author
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Ayman Mohamamdy Atta, Abdelrahman O. Ezzat, Sami A. Al-Hussain, Ahmed M. Tawfeek, and Hamad Abdulla Al-Lohedan
- Subjects
chemistry.chemical_compound ,Nanocomposite ,Sulfonate ,chemistry ,applied_chemistry ,Sodium ,chemistry.chemical_element ,Water treatment ,2-Acrylamido-2-methylpropane sulfonic acid ,Methylene blue ,Sodium salt ,Magnetite ,Nuclear chemistry - Abstract
Inorganic nanoparticles based on magnetite improve the mechanical, thermal, and magnetic properties of microporous cryogel polymer composites. Here we report the synthesis of microporous cryogel based on the crosslinked sodium vinyl sulfonate (Na-VS) and 2-acrylamido-2-methylpropane sulfonic acid sodium salt (Na-AMPS). The magnetite nanoparticles were inserted into Na-VS/Na-AMPS cryogel either during its crosslinking polymerization or by in-situ technique after its crosslinking. The morphology, particle sizes, thermal stability and magnetite contents of Na-VS/Na-AMPS cryogel and its magnetite composites were investigated. The prepared Na-VS/Na-AMPS cryogel and its magnetite composites were used as adsorbents for methylene blue (MB) cationic dye using optimum conditions. The magnetite Na-VS/Na-AMPS cryogel composite prepared by in-situ technique achieved the best adsorption MB removal capacity for 7 cycles among the other adsorbents via chemical adsorption mechanism at room temperature.
- Published
- 2018
32. Characterization of reactive amphiphilic montmorillonite nanogels and its application for removal of toxic cationic dye and heavy metals water pollutants
- Author
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Z.A. ALOthman, Ayman M. Atta, Ahmed M. Tawfeek, Ahmed A. Abdel-Khalek, and Hamad A. Al-Lohedan
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Chemistry ,General Chemical Engineering ,Metal ions in aqueous solution ,Intercalation (chemistry) ,Inorganic chemistry ,Portable water purification ,Exfoliation joint ,Chloride ,chemistry.chemical_compound ,Adsorption ,Montmorillonite ,Chemical engineering ,mental disorders ,medicine ,Nanogel ,medicine.drug - Abstract
The present work aims to reduce the water surface tension using dispersed organophilic clay minerals to increase the adsorption water pollutants (organic and inorganic) into the clay galleries. Therefore, sodium montmorillonite (Na-MMT) was functionalized with amphphiles based on crosslinked nanogel polymers of N-isopropylacrylamide (NIPAm), sodium 2-acrylamido-2-methylpropane sulfonate (Na-AMPS), acrylamide (AAm) and acrylamidopropyl)trimethylammonium chloride solution (APTAC) using surfactant free technique. The chemical interactions between nanogels and Na-MMT and their chemical structure were confirmed by FTIR analysis. The intercalation and exfoliation of Na-MMT were confirmed by wide-angle X-ray diffraction. The morphology of Na-MMT nanogel composites was investigated by TEM 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 nanogels reduced the surface tension of water and efficiently remove dye and metal ions from water.
- Published
- 2015
33. Role of Doppler US and MRI in diagnosis of placenta accreta
- Author
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Manal Hamisa, Emad M. Mashaly, Samer Fathy, and Ahmed M. Tawfeek
- Subjects
medicine.medical_specialty ,Placenta accreta ,business.industry ,Ultrasound ,lcsh:R ,lcsh:Medicine ,General Medicine ,Previous cesarean delivery ,medicine.disease ,Placenta previa ,Clear zone ,Placenta accreta (PA) ,Cesarean section (cs) ,Retroplacental complex (RPC) ,medicine ,Fast low angle shot (FLASH) ,Single shot fast spin echo (SSFSE) ,Myometrial thickness ,In patient ,Doppler ultrasound ,Radiology ,Magnetic resonance imaging (MRI) ,business ,reproductive and urinary physiology - Abstract
The aim of this work is to evaluate the role of Doppler US and MRI in the diagnosis of placenta accreta.Patients and methods: During period between 2012 to 2013, 120 pregnant patients with previous cesarean section were investigated by ultrasound and Doppler and then in suspected cases MRI was obtained (10 cases). The Sonographic and MRI diagnoses were compared with the final pathologic or operative findings or with both.Results: The mean age of this study group was 29 years ranging from 20 to 40. Among patients with confirmed placenta accreta, the mean age was 32.25 ranging from 25 to 40 years. The mean parity of patients ranged from 1 to 6 with a mean of 1.6. Among patients with placenta accreta, the mean parity ranged from 2 to 6 with a mean of 3.75. The total number of cases with placenta accreta in this study was 4, all of which were previa. This was out of a total of 25 cases of placenta previa. Transabdominal US features were the presence of intraplacental lacunae (sonolucencies), loss of retroplacental clear zone and disruption of bladder–uterine serosa interface with smallest myometrial thickness
- Published
- 2015
34. A new ion-selective electrode for potentiometric determination of Ce(III) ions
- Author
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Mohamed B. Saleh, Moustafa M.R. Khalaf, Ahmed A. Abdel Gaber, and Ahmed M. Tawfeek
- Subjects
Detection limit ,Chemistry ,Potentiometric titration ,Inorganic chemistry ,Metals and Alloys ,Analytical chemistry ,Ionophore ,chemistry.chemical_element ,Condensed Matter Physics ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Ion ,Ion selective electrode ,Cerium ,Membrane ,Electrode ,Materials Chemistry ,Electrical and Electronic Engineering ,Instrumentation - Abstract
A novel ion-selective PVC membrane sensor for cerium(III) ions based on [4-(4′-nitrobenzyl)-1-phenyl-3,5-pyrazolidinedion)] (NBPP) as a new ionophore has been prepared and studied. This electrode has a wide linear dynamic range from 10−1 to 2.5 × 10−6 mol l−1 with a Nernstian slope of 19.5 ± 0.2 mV decade−1 and low detection limit of 1.6 × 10−6 mol l−1. It has a fast response time (
- Published
- 2006
35. Novel Sm(III) Ion‐Selective Polymeric Membrane Sensor Based on Spiro[Oxirane‐Pyrazolidinedione] Derivative Ionophore
- Author
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Moustafa M.R. Khalaf, Mohamed B. Saleh, Ahmed A. Abdel Gaber, and Ahmed M. Tawfeek
- Subjects
Chemistry ,Metal ions in aqueous solution ,Biochemistry (medical) ,Clinical Biochemistry ,Inorganic chemistry ,Potentiometric titration ,Ionophore ,Biochemistry ,Oxalate ,Analytical Chemistry ,Ion selective electrode ,chemistry.chemical_compound ,Membrane ,Stability constants of complexes ,Electrochemistry ,Selectivity ,Spectroscopy - Abstract
A poly vinyl chloride (PVC) membrane sensor for Sm(III) ions based on [1-phenyl-3'(2-nitrophenyl) spiro[Oxirane-2.4-Pyrazoline]-3,5-dione] (PNSOP) as a membrane carrier was developed. This sensor exhibits a rapid and good Nemstian response towards Sm(III) ions in the range of 10 -1 to 10 -6 mol l -1 with a slope of 19.3 + 0.2mV per decade and a detection limit of 6.1 x 10 -7 mol l -1 . The sensor response and selectivity remained almost unchanged for at least 4 months. It has a fast response time about of 5 s. The sensor can be used in a pH range from 4.0 to 8.2 and demonstrates good discriminating power over a wide variety of other metal ions. The formation constant of ionophore complex with Sm(III) was calculated by using the segmented sandwich membrane method. The nature of the PNSOP ionophore and its Sm(III) complex is examined using Fourier-transform infrared analysis and elemental analysis technique. The proposed sensor was successfully applied as an indicator electrode in potentiometric titration of oxalate and carbonate ions and determination of acetylsalicylate and carbonate ions in some drugs.
- Published
- 2006
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