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Insights into the adsorption performance and mechanism of Cr(Ⅵ)onto porous nanocomposite prepared from gossans and modified coal interface:Steric,energetic,and thermodynamic parameters interpretations

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Chinese Journal of Chemical Engineering 2023年第9期61卷 118-128页

作者： Mohamed Mobarak Saleh Qaysi Mohamed Saad ahmed Yasser F.Salama ahmed Mohamed Abbass Mohamed Abd Elrahman Hamdy Aabdel-Gawwad Moaaz k.Seliem Physics Department Faculty of ScienceBeni-Suef UniversityEgypt Geology and Geophysics Department College of ScienceKing Saud University11451 RiyadhSaudi Arabia Geology Department Faculty of ScienceBeni-Suef UniversityEgypt Department of Building Materials and Construction ChemistryInstitute of Civil EngineeringTechnische Universitat BerlinBerlinGermany Structural Engineering Department Faculty of EngineeringMansoura UniversityMansouraEgypt Raw Building Materials and Processing Technology Research Institute Housing and Building National Research Center(HBRC)CairoEgypt Faculty of Earth Science Beni–Suef UniversityEgypt

Herein,iron oxide/hydroxides deposits(gossans)were utilized,for the first time,in the fabrication of magnetite nanoparticles(MNPs)to load modified coal(MC).The as-synthesized MNPs@MC composite was characterized via different techniques and utilized for the Cr(Ⅵ)remediation.Experimental studies supported by theoretical treatment were applied to offer a new overview of the Cr(Ⅵ)adsorption geometry and mechanism at 25-45℃.Experimental results suggested that the Cr(Ⅵ)uptake was mainly governed by adsorption-reduction coupled mechanism.The Langmuir model fitted well the Cr(Ⅵ)adsorption data with maximum adsorption capacities extended from 115.24 to 129.63 mg·g^(-1).Theoretical calculations indicated that Cr(Ⅵ)ions were adsorbed on the MNPs@MC following the theory of the advanced monolayer statistical model.The number of ions removed per site ranged from 1.88 to1.23 suggesting the involvement of vertical geometry and multi-ionic mechanism at all temperatures.The increment of the active sites density and the adsorption capacity at saturation with improving temperature reflected an endothermic process.Energetically,the Cr(Ⅵ)adsorption was controlled by physical forces as the adsorption energies were less than 40 kJ·mol^(-1).The calculated free enthalpy,entropy.and internal energy explained the spontaneous nature and the viability of Cr(Ⅵ)adsorption on the MNPs@MC adsorbent.These results offer a new approach in utilizing the iron-rich deposits as gossans in the preparation of magnetic and low-cost adsorbents for wastewater remediation.

关键词： Coal Magnetic nanoparticles Cr(Ⅵ)adsorption Statistical models Thermodynamic parameters

Hepatocellular Carcinoma:Diagnosis, Treatment Algorithms, and Imaging Appearance after Transarterial Chemoembolization

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Journal of Clinical and Translational Hepatology 2018年第2期6卷 175-188页

作者： Patrick Vande Lune ahmed k.abdel Aal Sergio klimkowski Jessica G.Zarzour Andrew J.Gunn University of Alabama at Birmingham School of Medicine BirminghamALUSA Division of Vascular and Interventional Radiology Department of RadiologyUniversity of Alabama at BirminghamBirminghamALUSA Department of Radiology University of Alabama at BirminghamBirminghamALUSA Division of Abdominal Imaging Department of RadiologyUniversity of Alabama at BirminghamBirminghamALUSA

Hepatocellular carcinoma(HCC)is a common cause of cancer-related death,with incidence increasing worldwide.Unfortunately,the overall prognosis for patients with HCC is poor and many patients present with advanced stages of disease that preclude curative therapies.Diagnostic and interventional radiologists play a key role in the management of patients with HCC.Diagnostic radiologists can use contrast-enhanced computed tomography(CT),magnetic resonance imaging,and ultrasound to diagnose and stage HCC,without the need for pathologic confirmation,by following established criteria.Once staged,the interventional radiologist can treat the appropriate patients with percutaneous ablation,transarterial chemoem-bolization,or radioembolization.Follow-up imaging after these liver-directed therapies for HCC can be characterized according to various radiologic response criteria;although,enhancement-based criteria,such as European Association for the Study of the Liver and modified Response Evaluation Criter in Solid Tumors,are more reflective of treatment effect in HCC.Newer imaging technologies like volumetric analysis,dual-energy CT,cone beam CT and perfusion CT may provide additional benefits for patients with HCC.

关键词： Interventional radiology Interventional oncology Hepatocellular carcinoma Response criteria Transarterial chemoembolization Diagnostic radiology

Effect of Pd or Ir on the catalytic performance of Mo/H-ZSM-5 during the non-oxidative conversion of natural gas to petrochemicals

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Journal of Natural Gas Chemistry 2008年第4期17卷 337-343页

作者： ahmed k.Aboul-Gheit ahmed E.Awadallah Salah M.El-kossy abdel-Lateef H.Mahmoud Process Development Division Egyptian Petroleum Research Institute Faculty of Science Department of ChemistryMNF University Ageeba Petroleum Co.

Natural gas conversion to petrochemicals, principally, benzene, naphthalene, toluene, as well as ethylene under non-oxidative conditions was examined in a fixed bed flow reactor at 700 ℃ and gaseous hourly space velocity （GHSV） of 1500 ml·g ^-1·h^-1 at time-on-stream ranging from 5 rain to 4 h using catalysts containing 6.0%Mo/H-ZSM-5 promoted with Pd or Ir metal. The catalysts were characterized by XRD, TPD, and TGA. The addition of Pd or Ir to 6%Mo/H-ZSM-5 catalyst promoted ethylene production but inhibited the cyclization reaction to aromatics owing to the strong interaction between these noble metals and the framework Al species, which were attached to the acid sites during the impregnation process. Coke deposition on the catalysts was found to decrease upon addition of 0.5wt% of Pd or Ir to 6%Mo/H-ZSM-5 catalyst owing to the hydrogenating activity of these metals.

关键词： natural gas methane benzene ethylene molybdenum Pd Ir H-ZSM-5

Thermomechanical Behavior of Brake Drums Under Extreme Braking Conditions

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Computers, Materials & Continua 2022年第8期72卷 2259-2273页

作者： T.khatir M.Bouchetara k.Derrar M.Djafri S.khatir M.abdel Wahab Institute of Science and Technology University Center Salhi Ahmed NaamaAlgeria Laboratory of Gas Combustion and Environment University of Sciences and Technology of OranL.P 1505 El-MenaouerOranUSTO 31000Algeria High School of Aeronautic Techniques Dar El Beida Algeria Ho Chi Minh City Open University Ho Chi Minh CityViet Nam Faculty of Engineering Van Lang UniversityHo Chi Minh CityVietnam Soete Laboratory Faculty of Engineering and ArchitectureGhent UniversityTechnologieparkZwijnaarde 903B-9052 ZwijnaardeBelgium

Braking efficiency is characterized by reduced braking time and distance,and therefore passenger safety depends on the design of the braking system.During the braking of a vehicle,the braking system must dissipate the kinetic energy by transforming it into heat energy.A too high temperature can lead to an almost total loss of braking efficiency.An excessive rise in brake temperature can also cause surface cracks extending to the outside edge of the drum friction surface.Heat transfer and temperature gradient,not to forget the vehicle’s travel environment(high speed,heavy load,and steeply sloping road conditions),must thus be the essential criteria for any brake system design.The aim of the present investigation is to analyze the thermal behavior of different brake drum designs during the single emergency braking of a heavy-duty vehicle on a steeply sloping road.The calculation of the temperature field is performed in transient mode using a three-dimensional finite element model assuming a constant coefficient of friction.In this study,the influence of geometrical brake drum configurations on the thermal behavior of brake drums with two different materials in grey cast iron FG200 and aluminum alloy 356.0 reinforced with silicon carbide(SiC)particles is analyzed under extreme vehicle braking conditions.The numerical simulation results obtained using FE software ANSYS are qualitatively compared with the results already published in the literature.

关键词： Drum brake finite element method braking energy distribution friction heat power friction heat flux transient temperature field

Improvement of Selected Morphological, Physiological, and Biochemical Parameters of Banana (Musa acuminata L.) Using Potassium Silicate under Drought Stress Condition Grown in vitro

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Phyton-International Journal of Experimental Botany 2023年第4期92卷 1019-1036页

作者： Hosny abdel Aziz Mohamed Sharaf Magdy Omar ahmed Abou El-Yazied Nada Ibrahim AlJwaizea Shaimaa Ismail Mohamed M.A.Omar khadiga Alharbi Amr Elkelish Moataz Tawfik Department of Horticulture Faculty of AgricultureAl-Azhar UniversityCairo11651Egypt Department of Biochemistry Faculty of AgricultureAl-Azhar UniversityCairo11651Egypt Department of Biochemistry and Molecular Biology College of Marine Life SciencesOcean University of ChinaQingdao266003China Department of Agricultural Botany Faculty of AgricultureAl-Azhar UniversityNasr CityCairo11751Egypt Department of Horticulture Faculty of AgricultureAin Shams UniversityCairo11566Egypt Department of Biology College of SciencePrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Biochemistry Faculty of AgricultureAin Shams UniversityCairo11566Egypt Biology Department College of ScienceImam Mohammad ibn Saud Islamic University(IMSIU)Riyadh11623Saudi Arabia Botany Department Faculty of ScienceSuez Canal UniversityIsmailia41522Egypt Botany Department Faculty of SciencePort Said UniversityPort Said42511Egypt

Drought stress has become more common in recent years as a result of climate change impacts on the production of banana crops and other fruit trees.The growth and productivity of Musa spp are severely impacted by the gradual degradation of water resources and the erratic distribution pattern of annual precipitation amount.The aim of the work includes increased drought tolerance in light of water scarcity in the world as a result of the bananas’being gluttonous for water needs.This investigation was carried out from 2019 to 2020 to study the effect of potassium silicate on morphological growth and biochemical parameters of Musa acuminata L under drought stress by PEG.As a result,drought stress reduced the morphological characteristics such as shoots number,shoot length,roots number,and survival percentage and biochemical characteristics such as chlorophyll a,b,carotenoids,stomatal status,and RWC.While proline content increased in the leaf of M.acuminata L.Media complemented with k2SiO3(2 to 6 mM)either individually or in combination with PEG led to an improvement in all morphological and biochemical characteristics.The activities of CAT,POD,and PPO enzymes increased significantly compared to control.Furthermore,the lowest PPO,CAT,and POD activity were achieved.Additionally,k2SiO3 treatments under drought stress successfully enhanced the leaf stomatal behavior.Our results suggest that k2SiO3 can help to maintain plant integrity in the tested cultivar under drought stress.

关键词： Musa acuminata L potassium silicate photosynthetic pigments stomata enzymatic activity

First United Arab Emirates consensus on diagnosis and management of inflammatory bowel diseases:A 2020 Delphi consensus

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World Journal of Gastroenterology 2020年第43期26卷 6710-6769页

作者： Maryam Alkhatry Ahmad Al-Rifai Vito Annese Filippos Georgopoulos Ahmad N Jazzar ahmed M khassouan zaher koutoubi Rahul Nathwani Mazen S Taha Jimmy k Limdi Gastroenterology and Endoscopy Department Ibrahim Bin Hamad Obaid Allah HospitalMinistry of Health and PreventionRas Al KhaimanUnited Arab Emirates Department of Gastroenterology Sheikh Shakbout Medical CityAbu DhabiUnited Arab Emirates Department of Gastroenterology Valiant ClinicDubaiUnited Arab Emirates Department of Gastroenterology and Endoscopy American HospitalDubaiUnited Arab Emirates Gastroenterology and Endoscopy Unit Al Zahra HospitalDubaiUnited Arab Emirates Gastroenterology Division Sheikh Khalifa Medical CityAbu DhabiUnited Arab Emirates Digestive Disease Unit Rashid HospitalDubaiUnited Arab Emirates Digestive Disease Institute Cleveland ClinicAbu DhabiUnited Arab Emirates Department of Gastroenterology Mediclinic City HospitalDubaiUnited Arab Emirates Gastroenterology and Hepatology Tawam HospitalAl AinUnited Arab Emirates Department of Gastroenterology The Pennine Acute Hospitals NHS TrustManchester Academic Health SciencesUniversity of ManchesterManchester M85RBUnited Kingdom

Ulcerative colitis and Crohn’s disease are the main entities of inflammatory bowel disease characterized by chronic remittent inflammation of the gastrointestinal tract.The incidence and prevalence are on the rise worldwide,and the heterogeneity between patients and within individuals over time is striking.The progressive advance in our understanding of the etiopathogenesis coupled with an unprecedented increase in therapeutic options have changed the management towards evidence-based interventions by clinicians with patients.This guideline was stimulated and supported by the Emirates Gastroenterology and Hepatology Society following a systematic review and a Delphi consensus process that provided evidence-and expert opinion-based recommendations.Comprehensive up-to-date guidance is provided regarding diagnosis,evaluation of disease severity,appropriate and timely use of different investigations,choice of appropriate therapy for induction and remission phase according to disease severity,and management of main complications.

关键词： Ulcerative colitis Crohn’s disease Infliximab Adalimumab Vedolizumab Ustekinumab Tofacitinib

Geology and Mineral Chemistry of Uranium-and Thorium-bearing Minerals in Rare-Metal(NYF)Pegmatites of Um Solimate,South Eastern Desert,Egypt

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Acta Geologica Sinica(English Edition) 2021年第5期95卷 1568-1582页

作者： Mohamed A.ALI ahmed E.abdel GAWAD Mohamed M.GHONEIM Nuclear Materials Authority 530 El-MaadiCairoEgypt

The garnet muscovite granitic pegmatite of Um Solimate,in southern Egypt,represents a promising asset for strategic and economic metals,especially Bi-Ni-Ag-Nb-Ta as well as U and Th.The ore bodies occur as large masses,pockets and/or veins of very coarse-grained pegmatites,which consist mainly of k-feldspar,quartz and albite with subordinate muscovite,garnet,and biotite.Radiometric data revealed that e U-and e Th-contents of the pegmatites reach up to 39 ppm and 82 ppm,respectively.The studied pegmatites are enriched in primary U and Th minerals(uraninite,coffinite,thorianite and uranothorite)as well as Hf-rich zircon and monazite,which give rise to anomalous radioactive zones.Niobium-tantalium-bearing minerals(i.***.ferrocolumbite,microlite and uranopyrochlore),xenotime,barite,galena,fluorite,and apatite are ubiquitous,and,consequently,the studied pegmatites belong tothe Niobium-Yttrium-Fluorine-type(NYF)family.The noble metal mineralization includes argentite(Ag_(2)S),native Ni and Bi as well as bismite and bismoclite.In addition,beryl and tourmaline are observed in pegmatites near the contact with metasediments and ultramafic bodies.The observed compositional variations of Ta/(Ta+Nb)and Mn/(Mn+Fe)ratios in columbite(0.08-0.45 and 0.11-0.57,respectively)and Hf contents in zircon(3.54-6.46 wt%)may reflectan extreme degree of magmatic fractionation leading to formation of the pegmatite orebody.

关键词： radioactivity rare-metal mineralization pegmatites U/Th-bearing minerals Um Solimate Egypt

Regulatory and activated effector T cells in chronic hepatitis C virus: Relation to autoimmunity

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World Journal of Hepatology 2016年第30期8卷 1287-1294页

作者： Hanan Fouad Maissa El Raziky Eman Medhat Hassan Ghada Mahmoud abdel Aziz Samar k Darweesh ahmed Reda Sayed Department of Medical Biochemistry Faculty of Medicine Cairo University Department of Pharmacology and Toxicology Faculty of Pharmacy Hail University Department of Hepato-gastroenterology and Tropical Medicine Faculty of Medicine Cairo University Department of Medical Biochemistry Faculty of Medicine Beni Suef University

AIM To investigate how Tregs are regulated in chronic hepatitis C virus(HCV) patients via assessment of Tregs markers(granzyme 2, CD69 and FoxP3), Teffs markers [TNFRSF4(OX40), INFG] and CD4, CD25 genes. METHODS A prospective study was conducted on 120 subjects divided into 4 groups: Group Ⅰ(n = 30) treatment na?ve chronic HCV patients; Group Ⅱ(n = 30) chronic HCV treated with Peg/Riba; Group Ⅲ(n = 30) chronic HCV associated with non-organ specific autoantibody and Group Ⅳ(n = 30) healthy persons as a control group. Tregs and Teffs markers were assessed in peripheral blood mononuclear cells by quantitative real time reverse transcriptase-polymerase chain reaction. RESULTS Chronic HCV patients exhibited significant higher levels of both Teffs and Tregs in comparison to healthy control group. Tregs markers were significantly decreased in Peg/Riba treated HCV patients in comparison to treatment na?ve HCV group. In HCV patients with antinuclear antibody(ANA) +ve, Tregs markers were significantly decreased in comparison to all other studied groups. Teffs markers were significantly elevated in all HCV groups in comparison to control and in HCV group with ANA +ve in comparison to treatment na?ve HCV group.CONCLUSION Elevated Tregs cells in chronic HCV patients dampen both CD4^+ and CD8^+ autologous T cell immune response. Interferon-α and ribavirin therapy suppress proliferation of Tregs. More significant suppression of Tregs was observed in HCV patients with autoantibodies favoring pathological autoimmune response.

关键词： Autoimmunity T 规章的房间丙肝病毒 T 使活跃之物房间干扰素

Nanofibrous ε-polycaprolactone scaffolds containing Ag-doped magnetite nanoparticles: Physicochemical characterization and biological testing for wound dressing applications in vitro and in vivo

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Bioactive Materials 2021年第7期6卷 2070-2088页

作者： M.k.ahmed M.A.Zayed S.I.El-dek Mayssa abdel Hady Doaa H.El Sherbiny Vuk Uskokovic Faculty of Nanotechnology for Postgraduate studies Cairo UniversityEl-Sheikh Zayed 12588Egypt Department of Physics Faculty of ScienceSuez UniversitySuez 43518Egypt Chemistry Department Faculty of ScienceCairo University12613GizaEgypt Materials Science and Nanotechnology Department Faculty of Postgraduate Studies for Advanced SciencesBeni-Suef UniversityBeni SuefEgypt Pharmaceutical Technology Department National Research CentreDokiiGizaEgypt Advanced Materials and Nanobiotechnology Laboratory TardigradeNano LLCIrvineCA92604USA Department of Biochemistry Faculty of DentistryModern University for Technology and InformationMokattamCairoEgypt

Skin wounds can lead to numerous complications with dangerous health consequences.In this work,magnetite nanoparticles were doped with different concentrations of antimicrobial silver(Ag)ions and incorporated into the electrospun nanofibrous ε-polycaprolactone(PCL)scaffolds.Nanoparticles and scaffolds with various Ag contents were characterized using a range of physicochemical techniques.Ag entered magnetite as cations and preferentially positioned at tetrahedral sites,introducing lattice distortions and topographic irregularities.Amorphization of the structure due to accommodation of Ag expanded the lattice in the bulk and contracted it on the surface,where broadened distribution of Fe-O coordinations was detected.Promoting spin canting and diminishing the double exchange interaction through altered distribution of ferric and ferrous ions,Ag softened the magnetism of magnetite.By making the nanoparticle structure more defective,Ag modified the interface with the polymer and promoted the protrusion of the nanoparticles from the surface of the polymeric nanofibers,thus increasing their roughness and hydrophilicity,with positive repercussions on cell adhesion and growth.Both the viability of human melanocytes and the antibacterial activity against E.coli and S.aureus increased with the concentration of Ag in the magnetite phase of the scaffolds.Skin wound healing rate in rats also increased in direct proportion with the concentration of Ag in the magnetite phase,and no abnormalities in the dermal and epidermal tissues were visible on day 10 in the treatment group.These results imply an excellent potential of these composite nanofibrous scaffolds for use as wound dressings and in other reconstructive skin therapies.

关键词： Tissue engineering Wound healing Skin Magnetic nanoparticles Nanofiber