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Effect of Aging on the Toughness of Austenitic and Duplex Stainless Steel Weldments

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Journal of Materials Science & Technology 2010年第9期26卷 810-816页

作者： Omyma hassan Ibrahim Ibrahim Soliman Ibrahim Tarek ahmed Fouad Khalifa Metallurgy Dept. Nuclear Research CentreAtomic Energy Authority(Egypt) Nuclear Safety Centre Atomic Energy Authority(Egypt) Shoubra Faculty of Engineering Benha University

In the present study,the effect of aging heat treatment at 650,750,and 850？C on the impact toughness of 316L austenitic stainless steel,2205 duplex stainless steel and their weldments has been *** process was conducted using the TIG（tungsten inert gas） welding *** impact testing,at room temperature,was employed to determine the effect of aging treatment on the impact properties of investigated *** treatment resulted in degradation in the impact toughness as demonstrated by the reduction in the impact fracture energy and deformation parameters（strain hardening capacity,fracture deffection,and crack initiation and propagation energy）.The degree of embrittlement was more noticeable in duplex stainless steel parent and weld-metal than in 316L stainless steel and became greater with the increase of aging *** degradation in impact toughness was discussed in relation to the observed precipitation of the intermetallic sigma phase in the microstructure of the stainless steel weldments and the corresponding fracture surface morphology.

关键词： Austenitic and duplex stainless steels Aging Instrumented impact Toughness

Green synthesis of bentonite-supported iron nanoparticles as a heterogeneous Fenton-like catalyst:Kinetics of decolorization of reactive blue 238 dye

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Water Science and Engineering 2020年第4期13卷 286-298页

作者： ahmed Khudhair hassan Ghayda Yaseen Al-Kindi Dalal Ghanim Environment and Water Directorate Ministry of Science and TechnologyBaghdad 10070Iraq Sanitary and Environmental Branch Civil Engineering DepartmentUniversity of TechnologyBaghdad 10009Iraq

This study aimed to synthesize green tea nano zero-valent iron(GT-NZVI)and bentonite-supported green tea nano zero-valent iron(BGT-NZVI)nanoparticles using green tea extracts in an environmentally sustainable *** was used as a support material because it disperses and stabilizes GT-NZVI,and it helps to reduce the cost,increase the adsorption capacity of GT-NZVI,and decrease the optimum amount of GT-NZVI used in Fenton-like oxidation.A scanning electron microscope,an atomic force microscope,and a Fourier transform infrared spectroscope were used to characterize GT-NZVI and B-GT-NZVI,while the zeta potential was measured to evaluate the stability of iron *** decolorization kinetics of reactive blue 238(RB 238)dye in the aqueous phase in the Fenton-like oxidation process were investigated as *** effects of various experimental conditions such as reaction time,dosages of catalysts,concentration of H2O2,temperature,addition of inorganic salts,and other parameters were *** results show that the oxidative degradation efficiencies of RB 238 dye catalyzed by GT-NZVI and B-GT-NZVI were 93.5%and 96.2%,respectively,at the optimum reaction conditions as follows:c(H2O2)¼5 mmol/L,r(GT-NZVI)¼0.5 g/L or r(B-GT-NZVI)¼0.5 g/L,c(RB 238 dye)¼0.05 mmol/L,and pH¼2.5 at 180 *** best catalytic performance was exhibited when B-GT-NZVI was *** kinetic models were employed,and the second-order model was found to be the best model representing the experimental kinetic data of RB 238 *** value of activation energy decreased from 38.22 kJ/mol for GT-NZVI to 14.13 kJ/mol for *** indicates that the effect of B-GT-NZVI in decreasing the energy barrier is more pronounced than that of the GT-NZVI catalyst,leading to improved Fenton-like oxidation processes.©2020 Hohai *** and hosting by Elsevier *** is an open access article under the CC BY-NC-ND license(http://***/licenses/by-nc-nd/4.0/).

关键词： Green synthesis Bentonite-supported iron nanoparticles Azo dye Fenton-like process Kinetics

Handy locoregional flaps for nasal reconstruction

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Chinese Journal of Plastic and Reconstructive Surgery 2023年第1期5卷 13-19页

作者： ahmed hassan El-Sabbagh Plastic Surgery Center Faculty of MedicineMansoura UniversityElgomhouria StreetMansoura 35516Egypt

Background Skin lesions on the nose are *** surgical techniques have been used for nasal *** options may be autogenous or alloplastic and can be performed in single or multiple *** choice of coverage depends on the nature of the lesion,location on the nose,and available donor *** study aimed to evaluate the surgical outcomes of using locoregional flaps for nasal *** A total of 27 patients underwent *** were 9 men and 18 women,aged 7 months to 93 *** patients presented with involuting hemangioma,five patients with ischemic necrosis of the columella,and five patients with congenital nevus;the remaining 13 patients were previously diagnosed with basal cell *** techniques have been described for nasal reconstruction at our institution from 2016 to *** patients had basal cell carcinoma(n=13).Locoregional flaps and primary sutures were used for nasal *** The complications were *** patient had a superficial infection and one experienced postoperative *** recurrence was observed,and none of the patients asked for a second *** Radical excision of tumors combined with analysis of nasal defects and nearby donor sites is essential for nasal *** use of locoregional flaps leads to consistent and good aesthetic outcomes.

关键词： Nose Skin defect Pedicled flap

Hydrocarbon generating-potential and maturity-related changes of the Khatatba Formation, Western Desert, Egypt

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Petroleum Research 2019年第2期4卷 148-163页

作者： Mohammed A.ahmed Mostafa M.A.hassan Geology Department Faculty of ScienceMansoura University35516MansouraEgypt Egyptian General Petroleum Corporation CairoEgypt

The petroliferous province of the Western Desert comprises several sedimentary basins with different hydrocarbon potentiality and production *** middle Jurassic Khatatba Formation was proved a potential source rock in some basins and active/effective in *** current study aims to give a comprehensive assessment and evaluation of the potential organic-rich intervals of the Khatatba Formation across JG and JD fields,northeast Abu Gharadig Basin(NEAG).The hydrocarbon generating capability and sourcing of the Khatatba Formation studied through organic geochemistry calibrated with well ***,the efficiency of some widely used plots of geochemistry is re-evaluated according to their accuracy and *** cuttings,thirteen cores and two oil samples obtained from three wells(JG-2,JG-3 and JD-4)were *** samples revealed total organic carbon(TOC)values ranging from 1 to 9 wt%,exhibiting a good-excellent potential source rock.A single sample in the JD-4 well attained a TOC value of 21.3 wt%with a generating potential(represented by S2 parameter)exceeding 146 mgHc/g rock required a special *** of the samples(mainly in the JD-4 well)attained a sufficient level of thermal maturity for hydrocarbon generation with a Tmax up to 449*** vitrinite reflectance(%Ro)values(a common maturity-related indicator)acquired from the JD-4 well ranging between 0.76%and 0.92%.These values are tediously increasing with depth indicating a uniform geothermal *** Khatatba organofacies,with wide variety of kerogen types(I,II,II-S and II/III),contain marine organic matter with a slight terrigenous input,exhibiting anoxic-suboxic environmental ***-source correlations define the organic-rich intervals responsible for charging the accumulated hydrocarbon in the NEAG concession.

关键词： NEAG concession Abu Gharadig Basin Source rock evaluation Khatatba Formation Well logging

IPv6 Cryptographically Generated Address:Analysis,Optimization and Protection

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Computers, Materials & Continua 2021年第7期68卷 247-265页

作者： Amjed Sid ahmed Rosilah hassan Faizan Qamar Mazhar Malik Department of Computing and Information Technology Global College of Engineering and TechnologyRuwi112Sultanate of Oman Faculty of Information Science and Technology Center for Cyber SecurityUniversiti Kebangsaan MalaysiaBangi43600Malaysia Faculty of Information Science and Technology Universiti Kebangsaan Malaysia43600BangiMalaysia

In networking,one major difficulty that nodes suffer from is the need for their addresses to be generated and verified without relying on a third party or public authorized *** resolve this issue,the use of selfcertifying addresses have become a highly popular and standardized method,of which Cryptographically Generated Addresses(CGA)is a prime *** was primarily designed to deter the theft of IPv6 addresses by binding the generated address to a public key to prove address *** though the CGA technique is highly effective,this method is still subject to several vulnerabilities with respect to security,in addition to certain limitations in its *** this study,the authors present an intensive systematic review of the literature to explore the technical specifications of CGA,its challenges,and existing proposals to enhance the *** that CGA generation is a time-consuming process,this limitation has hampered the application of CGA in mobile environments where nodes have limited energy and *** Hash2 conditions in CGA is the heaviest and most timeconsuming part of *** improve the performance of CGA,we replaced the Secure Hash Algorithm(SHA1)with the Message Digest(MD5)hash ***,this study also analyzes the possible methods through which a CGA could be *** conducting this analysis,Denial-of-Service(DoS)attacks were identified as the main method of attack toward the CGA verification process,which compromise and threaten the privacy of ***,we propose some modifications to the CGA standard verification algorithm to mitigate DoS attacks and to make CGA more security conscious.

关键词： IPv6 GCA SEND DoS attacks RSA SHA-1

Double-antibody-based nano-biosensing systemfor the onsite monitoring of SARS-CoV-2 variants

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Microsystems & Nanoengineering 2023年第4期9卷 247-262页

作者： Heba A.Hussein ahmed Kandeil Mokhtar Gomaa Rabeay Y.A.hassan Virology Department Animal Health Research Institute(AHRI)Agricultural Research Center(ARC)Giza 12619Egypt Biosensors Research Laboratory Zewail City of Science and Technology6th October CityGiza 12578Egypt Center of Scientific Excellence for Influenza Viruses Environmental Research DivisionNational Research CentreGiza 12622Egypt Nanoscience Program University of Science and Technology(UST)Zewail City of Science and TechnologyGiza 12578Egypt

The fast and reliable diagnosis of COVID-19 is the foremost priority for promoting public health ***, double-antibody-based immunobiosensor chips were designed, constructed, and exploited for clinicaldiagnosis. Gold nanoparticles/tungsten oxide/carbon nanotubes (AuNPs/WO3/CNTs) were used as the active workingsensor surface to support the chemical immobilization of a mixture of SARS-CoV-2 antibodies (anti-RBD-S and anti-RBD-S-anti-Llama monoclonal antibodies). The morphology and chemical functionalization of the fabricateddisposable immunochips was characterized using scanning electron microscopy (SEM), Fourier transform infrared(FTIR) spectroscopy, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). After full assayoptimization, the immunobiosensor showed a high sensitivity to detect SARS-CoV-2-S protein with limits of detectionand quantification of 1.8 and 5.6 pg/mL, respectively. On the other hand, for the SARS-CoV-2 whole virus particleanalysis, the detection and quantification limits were determined to be 5.7 and 17 pg/mL, respectively. The biosensorshowed a highly selective response toward SARS-CoV-2, even in the presence of influenza, nontargeting humancoronaviruses, and Middle East respiratory syndrome coronavirus (MERS-CoV). The immunochips exhibited distinctresponses toward the variants of concern: B.1>C.36.3>Omicron> Delta> Alpha coronavirus variants. For biosensorvalidation, twenty-nine clinical specimens were analyzed, and the impedimetric responses were positively detected fortwo Delta samples, eighteen Omicron samples, and six B.1-type samples in addition to three negative ***, the immunobiosensor was fabricated in the form of ready-to-use chips capable of sensitive detection ofvirus variants, especially variants of concern (VOC) and interest, in a specimen within 15 min. The chips providedinstantaneous detection with the direct application of clinical samples and are considered a point-of-care

关键词： system limits optimization

Synthesis of ZnO Nanoparticles onto Sepiolite Needles and Determination of Their Sensitivity toward Humidity, NO_2 and H_2

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Journal of Materials Science & Technology 2016年第6期32卷 573-582页

作者： M.hassan ahmed S.Afify J.M.Tulliani Department of Applied Science and Technology Politecnico di Torino

This work investigated the sensitivity toward humidity, NO2 and H2 of ZnO modified sepiolite （Si12Mg8O30（OH）4.（H2O）4.8H2O）. To this aim, sepiolite powder was first modified by leaching magnesium ions in HCI then by precipitating nano-sized Zn-based compounds under basic conditions. A subse- quent thermal treatment at 550 ℃ for 1 h was performed. The powders were characterized by X-ray diffraction （XRD）, specific surface area measurements, thermogravimetric and differential thermal anal- ysis and field emission scanning electron microscopy, as well as high resolution transmission electron microscopy. The XRD patterns showed that all leached heat treated samples were made of anhydrous sepiolite and of ZnO. Sensors were then obtained by screen printing these materials onto commercial alumina substrates with Pt electrodes. All the investigated compositions were capable of detecting NO2 down to ppm level and 20 ppm H2, at an optimal working temperature of 300°C. These detection limits are in line with the current best results reported in literature.

关键词： Clay minerals Gas sensor Sensitivity Hydrogen sensor Nitrogen Oxide

3D static reservoir modelling of Abu Madi paleo-valley in Baltim Field,Offshore Nile Delta Basin,Egypt

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Petroleum Research 2022年第4期7卷 473-485页

作者： Mohammad Abdelfattah Sarhan Tamer hassan ahmed Saied Ali Geology Department Faculty of ScienceDamietta University34517Egypt Qarun Petroleum Company(Apache J.V) New MaadiCairo11742Egypt

The 3D static reservoir modelling provides a good understanding for the hydrocarbon reservoir distri-bution and *** study aimed to construct a static model to study the gas-reservoir potentiality of the Messinian Abu Madi Formation in Baltim Field,offshore Nile Delta *** model was constructed based on the interpretation of the thirty-seven 2D seismic sections besides the analysis of well logs data for five drilled wells(Baltim East-2,Baltim East-3,Baltim East-5,Baltim North-1 and Baltim North-2).The seismic interpretation exposed that the Abu Madi incised valley in Baltim Field is oriented NNW-SSE with width ranges from 5 to 8 km and approximately 32 km in *** reservoir modelling revealed a relatively homogeneous reservoir facies qualities for gas production in two different zones within the Abu Madi *** trapping mechanism for these intervals is represented by pinching out in the two sides of the Abu Madi paleo-valley and bounded by two faults in the northern and southern parts of the study area.

关键词： Abu madi reservoir Baltim field Nile Delta Basin Seismic interpretation Static model Well logging

Geochemical characteristics of natural gases and source rocks in Obayied sub-basin,north Western Desert,Egypt:implications for gas-source correlation

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Acta Geochimica 2023年第2期42卷 241-255页

作者： Mostafa hassan Mahmoud Leila Mohammed ahmed Ghalib Issa Omar Hegab Geology Department Faculty of ScienceMansoura UniversityMansoura 35516Egypt Egyptian General Petroleum Corporation CairoEgypt

Western Desert represents a major oil and gas province in Egypt producing more than 50%of the country’s oil *** and gas blend occurs in most producing fields,however,the genetic link between gas and liquid hydrocarbon phases are not *** sub-basin in the Western Desert where oil and gas phases coexist in the Middle Jurassic sandstones of the Khatatba Formation provides an ideal place to investigate the link between oil and gas *** analyses on rock samples(Rock–Eval pyrolysis,vitrinite reflectance,R_(o))and gases(molecular and isotopic composition)were conducted in order to identify the genetic characteristics of the hydrocarbon phases ***-relevant parameters(Rock–Eval T_(max),vitrinite reflectance R_(o))elucidate that only Middle Jurassic Khatatba organofacies capable of generating wet and dry hydrocarbon ***,the enrichment of C_(7)normal alkanes,mono-branched alkanes relative to polybranched components in the Obayied gases reflect their generation via cracking of *** modelling results confirm gas generation through both primary and secondary ***,secondary cracking of liquid hydrocarbon phases is volumetrically more *** cracking of the Khatatba organofacies likely predate and catalyze the secondary cracking of the liquid phases and therefore the volume of generated gas increases incrementally eastward where both processes *** present study highlights the significant role of secondary cracking in the generation and accumulation of huge gas accumulations in the basins containing oil-prone source intervals.

关键词： Primary and secondary cracking Gas geochemistry Jurassic Khatatba Obayied Western Desert