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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1048-1071页

作者： Huajing Zong Nan Kang Zehao Qin mohamed el mansori Arts et Metiers Institute of Technology MSMPHESAM UniversitéChâlons-en-Champagne F-51006France Texas A&M Engineering Experiment Station Institute for Manufacturing SystemsCollege Station TX77843USA

The laser powder bed fusion(LPBF) process can integrally form geometrically complex and high-performance metallic parts that have attracted much interest,especially in the molds *** appearance of the LPBF makes it possible to design and produce complex conformal cooling channel systems in ***,LPBF-processed tool steels have attracted more and more *** complex thermal history in the LPBF process makes the microstructural characteristics and properties different from those of conventional manufactured tool *** paper provides an overview of LPBF-processed tool steels by describing the physical phenomena,the microstructural characteristics,and the mechanical/thermal properties,including tensile properties,wear resistance,and thermal *** microstructural characteristics are presented through a multiscale perspective,ranging from densification,meso-structure,microstructure,substructure in grains,to ***,a summary of tool steels and their challenges and outlooks are introduced.

关键词： additive manufacturing laser powder bed fusion tool steel multi-scaled structure mechanical properties thermal properties

Toward understanding the microstructure characteristics,phase selection and magnetic properties of laser additive manufactured Nd-Fe-B permanent magnets

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International Journal of Extreme Manufacturing 2024年第1期6卷 277-294页

作者： Bo Yao Nan Kang Xiangyu Li Dou Li mohamed el mansori Jing Chen Haiou Yang Hua Tan Xin Lin State Key Laboratory of Solidiffcation Processing Northwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Arts et Metiers Institute of Technology MSMPHESAM UniversitéF-51006 Chˆalons-en-ChampagneFrance Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Texas A&M Engineering Experiment Station Institute for Manufacturing SystemsCollege StationTX 77843United States of America

Nd-Fe-B permanent magnets play a crucial role in energy conversion and electronic *** essential magnetic properties of Nd-Fe-B magnets,particularly coercivity and remanent magnetization,are significantly infuenced by the phase characteristics and *** this work,Nd-Fe-B magnets were manufactured using vacuum induction melting(VIM),laser directed energy deposition(LDED)and laser powder bed fusion(LPBF)*** evolution and phase selection of Nd-Fe-B magnets were then clarified in *** results indicated that the solidification velocity(V)and cooling rate(R)are key factors in the phase *** terms of the VIM-casting Nd-Fe-B magnet,a large volume fraction of theα-Fe soft magnetic phase(39.7 vol.%)and Nd2Fe17Bxmetastable phase(34.7 vol.%)areformed due to the low R(2.3×10-1?C s-1),whereas only a minor fraction of the Nd2Fe14B hard magnetic phase(5.15 vol.%)is *** the LDED-processed Nd-Fe-B deposit,although the Nd2Fe14B hard magnetic phase also had a low value(3.4 vol.%)as the values of V(10-2m s-1)and R(1.45×106?C s-1)in the LPBF process resulted in the substantial formation of the Nd2Fe14B hard magnetic phase(55.8 vol.%)directly from the liquid,while theα-Fe soft magnetic phase and Nd2Fe17Bxmetastable phase precipitation are suppressed in the LPBF-processed Nd-Fe-B ***,crystallographic texture analysis reveals that the LPBF-processedNd-Fe-B magnets exhibit isotropic magnetic ***,the LPBF-processed Nd-Fe-B deposit,exhibiting a coercivity of 656 k A m-1,remanence of 0.79 T and maximum energy product of 71.5 k J m-3,achieved an acceptable magnetic perfor

关键词： laser additive manufacturing(LAM) Nd-Fe-B permanent magnets numerical simulation microstructure magnetic properties

Comparison between seismic analysis of twisting and regular 52-story towers considering soil-structure interaction

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 663-675页

作者： mohamed Naguib Abouelsaad Mohammed Shaaban Salah el Bagalaty mohamed E.el Madawy Structural Engineering Department Faculty of EngineeringMansura UniversityMansoura 35511Egypt Faculty of Engineering Delta University for Science and TechnologyGamasa 35712Egypt

A dynamic analysis of both twisting and regular towers is carried out to determine the results of considering soil-structure interaction(SSI)on high-rise *** addition,the difference between the seismic performance of using twisting towers over regular ones is *** twisting tower is a simulation of the Evolution Tower(Moscow).The towers’skeletons consist of RC elements and rest on a reinforced concrete piled-raft *** soil model is considered as multi-layered with the same soil properties as the zone chosen for the analysis(New Mansoura City,Egypt).The only difference between both towers is their shape in *** whole system is modelled and analyzed in a single step as one full 3D model,which is known as the direct approach in *** analyses are carried out using finite-element software(Midas GTS NX).Dynamic output responses due to three records of seismic loads are proposed and presented in some *** on the results,it is concluded that SSI has a considerable effect on the dynamic response of tall buildings mainly because of the foundation flexibility,as it leads to lengthening the vibration period,increasing the story drift and the base shear for both cases.

关键词： soil-structure interaction seismic analysis twisting towers base shear story drift finite element method Midas GTS NX

Hepatitis B virus as a risk factor for hepatocellular carcinoma:There is still much work to do

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Liver Research 2024年第2期8卷 83-90页

作者： Walaa Abdelhamed mohamed el-Kassas Endemic Medicine Department Sohag UniversitySohagEgypt Endemic Medicine Department Faculty of MedicineHelwan UniversityCairoEgypt Liver Disease Research Center College of MedicineKing Saud UniversityRiyadhSaudi Arabia

Hepatitis B virus(HBV)infection is a significant health problem that can result in progression to liver cirrhosis,decompensation,and the development of hepatocellular carcinoma(HCC).On a country level,the prevalence of chronic HBV infection varies between 0.1%and 35.0%,depending on the locality and the population being ***-third of all liver cancer fatalities worldwide are attributable to *** adoption of standard birth-dose immunization exerted the most significant impact on the decline of HBV *** incidence ranges from 0.01%to 1.40%in noncirrhotic patients and from 0.9%to 5.4%annually,in the settings of liver *** antiviral therapy significantly reduces the risk of developing HBV-related HCC,studies have demonstrated that the risk persists,and that HCC screening is still *** review discusses the complex relationship between HBV infection and HCC,recent epidemiological data,different aspects of clinical disease characteristics,and the impact of antiviral therapy in this context.

关键词： Hepatitis B virus(HBV) Hepatocellular carcinoma(HCC) HBV vaccine Carcinogenesis Antiviral therapy

Mafic and felsic magmatism in the Wadi Kalalat area, South Eastern Desert, Egypt: mineralogy, geochemistry and geodynamic evolution during the Neoproterozoic in the Nubian Shield

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Acta Geochimica 2024年第1期43卷 150-173页

作者： Adel A.Surour Ahmed A.Madani mohamed A.el-Sobky Faculty of Science Galala UniversityNew Galala CitySuez 43511Egypt Department of Geology Faculty of ScienceCairo UniversityGiza 12613Egypt Egyptian Mineral Resources Authority P.O.Box 11517AbbasiyaCairoEgypt

In the south Eastern Desert of Egypt,two contrasting types of magmatism(mafic and felsic) are recorded in the Wadi Kalalat area,and form the Gabal el Motaghiarat and Gabal Batuga intrusions,*** two intrusions post-dates ophiolitic and arc associations represented by serpentinite and metagabbro-diorite,*** mafic intrusion has a basal ultramafic member represented by fresh peridotite,which is followed upward by olivine gabbro and anorthositic or *** mafic intrusion pertains to the Alaskan-type mafic-ultramafic intrusions in the Arabian-Nubian Shield(ANS)being of tholeiitic nature and emplaced in a typical arc *** the other hand,the Gabal Batuga intrusion comprises three varieties of fresh A-type granites of high K-calc alkaline nature,which is peraluminous and garnetbearing in parts.A narrow thermal aureole in the olivine gabbro of the mafic intrusion was developed due to the intrusion of the Batuga *** results in the development of a hornfelsic melagabbro variety in which the composition changed from tholeiitic to a calc-alkaline composition due to the addition of S_(i)O_(2),Al_(2)O_(3),alkalis,lithosphile elements(LILEs) such as Rb(70 ppm) and Y(28 ppm) from the felsic *** the thermal aureole,Rb amounts 2-8 ppm and Y lies in the range elieved that the Gabal Batuga felsic intrusion started to emplace during the waning stage of an arc system,with transition from the pre-collisional(i.e.,arc setting) to post-collisional and within plate *** from which the Gabal Batuga granites were fractionated is high-K calc-alkaline giving rise to a typical post-collisional A-type granite(A_(2)-subtype) indicating an origin from an underplating crustal ***,it is stressed here that the younger granites in the ANS are not exclusively post-collisional and within-plate but most likely they started to develop before closure of the arc *** possible source(s) of mafic magmas

关键词： Wadi Kalalat Gabal el Motaghairat mafic intrusion Gabal Batuga felsic intrusion Arc setting Post-collision Within-plate

Evaluation of urea breath test as a diagnostic tool for Helicobacter pylori infection in adult dyspeptic patients

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World Journal of Gastroenterology 2024年第17期30卷 2302-2307页

作者： Zeinab Nabil Ahmed Said Asmaa mohamed el-Nasser Department of Medical Microbiology&Immunology Faculty of Medicine for Girls Al-Azhar UniversityNasr City 11754CairoEgypt

In this editorial,we discuss the article in the World Journal of *** article conducts a meta-analysis of the diagnostic accuracy of the urea breath test(UBT),a non-invasive method for detecting Helicobacter pylori(***)infection in *** is based on radionuclide-labeled *** methods,both invasive and non-invasive,are available for diagnosing *** infection,inclu-ding endoscopy with biopsy,serology for immunoglobulin titers,stool antigen analysis,and *** guidelines recommend UBTs as the primary choice for diagnosing *** infection and for reexamining after eradication *** is used to be the first choice non-invasive test due to their high accuracy,specificity,rapid results,and ***,its performance remains unaffected by the distribution of *** in the stomach,allowing a high flow of patients to be *** its widespread use,the performance characteristics of UBT have been inconsistently described and remain incompletely *** are two UBTs available with Food and Drug Administration approval:The 13C and 14C *** tests are affordable and can provide real-time *** may prefer the 13C test because it is non-radioactive,compared to 14C which uses a radioactive isotope,especially in young children and pregnant *** there was heterogeneity among the studies regarding the diagnostic accuracy of both UBTs,13C-UBT consistently outperforms the *** makes the 13C-UBT the preferred diagnostic ***,the provided findings of the meta-analysis emphasize the significance of precise considerations when choosing urea dosage,assessment timing,and measurement techniques for both the 13C-UBT and 14C-UBT,to enhance diagnostic precision.

关键词： Helicobacter pylori Urea breath test Diagnosis Diagnostic test accuracy Meta-analysis

Wood By-Products as UV Protection:A Consequence Review

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Journal of Renewable Materials 2024年第4期12卷 699-720页

作者： Naglaa Salem el‑Sayed mohamed Hasanin Samir Kamel Cellulose and Paper Department National Research CentreCairo12622Egypt

In recent decades,the ozone layer has suffered considerable damage,increasing the entry of ultraviolet(UV)light into the atmosphere and reaching the earth’s surface,negatively affecting ***,researchers aimed to solve this problem by synthesizing advanced UV-shielding *** the other hand,developing an easy and green strategy to prepare functional materials with outstanding properties based on naturally abundant and environmentally friendly raw materials is highly desirable for sustainable *** biomass-derived materials are sustainable and biodegradable,they present a promising substitute for petroleum-based *** three main structural constituents of the plant biomass-based materials that are naturally available are cellulose,hemicellulose,and *** review details current developments using wood-based products such as cellulose,hemicellulose,and lignin in UV-shielding *** will start with assembling the structure and chemistry of cellulose,hemicellulose,and lignin,followed by their contributions to preparing UV-shielding ***,it will briefly discuss the different processing methods for the design of UV-shielding *** wood by-products offer additional opportunities to use the whole tree harvest.

关键词： UV-shielding wood cellulose lignin hemicellulose sunlight protection

Dysprosium oxide,alumina,and graphene oxide reinforced polycaprolactone thin films:Thermal stability,morphology,and cell viability

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Journal of Rare Earths 2024年第7期42卷 1337-1343,I0005页

作者： mohamed Tharwat elabbasy mohamed R.Atteya Mai A.Samak Mousa Abdelrahman Tahani AlMahmoud M.A.el-Morsy A.A.Menazea M.F.H.Abd el-Kader Department of Public Health College of Public Health and Health InformaticsUniversity of Ha'ilHa'il2440Saudi Arabia Food Control Department Faculty of Veterinary MedicineZagazig UniversityZagazig44519Egypt Department of Physical Therapy College of Applied Medical SciencesUniversity of Ha'ilHa'ilSaudi Arabia Department of Histology and Cell Biology Faculty of MedicineZagazig UniversityZagazig44519Egypt College of Nursing University of Ha'ilHa'ilSaudi Arabia College of Science and Humanities in Al-Kharj Physics DepartmentPlasma Technology and Material Science UnitPrince Sattam Bin Abdulaziz UniversityAl-kharj11942Saudi Arabia Physics Department Faculty of ScienceUniversity of DamiettaNew Damietta34517Egypt Spectroscopy Department Physics Research InstituteNational Research CentreDokki12622GizaEgypt Biophysics Department Faculty of ScienceCairo UniversityGizaEgypt

Developing a biomaterial for wound healing applications is still a ***,dysprosium oxide(Dy_(2)O_(3)),aluminum oxide(Al_(2)O_(3)),and graphene oxide(GO)were embedded in cast films based on polycaprolactone(PCL)to be examined for wound dressing *** techniques were used to characterize the fabricated films including X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),Raman,and scanning electron microscopy(SEM),besides their biological *** thermogravimetric analysis(TGA)exhibits high thermal stability as the scaffold weight decreases slightly to 98.6%after raising the temperature from room temperature to 280℃.The cell viability was investigated and it is shown that the viable cells grow up to approximately 93%at 75μg/***,the cell attachment shows excellent behavior as the cells attach on most of the surface of the modified PCL which shows high biocompatibility.

关键词： Wound healing Polycaprolactone Dy203 Al203 Biocompatible Rare earths

Jellyfish-inspired alginate composite hydrogel filter prepared by macro-micro double bionic strategy for efficient water purification

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 141-157页

作者： Huiting Peng Yan Chen Jiaopan Lin Chelsea Benally mohamed Gamal el-Din Junkai Gao School of Naval Architecture and Marinetime Zhejiang Ocean UniversityZhoushan 316022China Department of Civil and Environmental Engineering University of AlbertaEdmontonAB T6G 1H9Canada

Recently,research on hydrogel materials with a porous structure and superior water absorption capabilities significantly ***,the hydrogel under gravity-driven separation conditions often exhibit an unstable pore structure,poor mechanical properties,and limited *** this end,this work presents a novel approach that combines a macro-micro double bionic strategy with a triple crosslinking method to develop a multifunctional alginate composite hydrogel filter(2%-SA-κCG-PVA-Ca^(2+),2%-SKP-Ca^(2+)for short)with a stable pore structure and superior mechanical properties,which possessed an umbrella-shaped structure resembling that of *** 2%-SKPCa^(2+)filter was synthesized using polyvinyl alcohol(PVA)as a stable structure-directing agent,and sodium alginate(SA)andκ-carrageenan(κ-CG)as polymer *** distinctive umbrellashaped hydrogel of 2%-SKP-Ca^(2+)filter,formed through the triple crosslinking method,overcomes the limitations of unstable pore structure and poor durability seen in hydrogels prepared by traditional crosslinking ***,the utilization of the 2%-SKP-Ca^(2+)filter in water treatment demonstrates its good selective permeability,excellent resistance to fouling,and extended longevity,which enables it to simultaneously achieve the multifunctional water purification and the coating of multi-substrate anti-fouling ***,not only does this research provide an efficient,multifunctional,highly pollution-resistant preparation method for designing a new filter,but it also confirms the application prospect of the macro-micro dual bionic strategy developed in this study in complex water treatment.

关键词： Triple crosslinking method Alginate Umbrella-shaped Jellyfish Water purification

Comparative study between three carbonaceous nanoblades and nanodarts for antimicrobial applications

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Journal of Environmental Sciences 2024年第2期136卷 594-605页

作者： mohamed S.Selim Ahmed M.Azzam mohamed A.Shenashen Shimaa A.Higazy Bayaumy B.Mostafa Sherif A.el-Safty National Institute for Materials Science(NIMS) 1-2-1 SengenTsukuba-ShiIbaraki-Ken 305-0047Japan Petroleum Application Department Egyptian Petroleum Research InstituteNasr City 11727Egypt Department of Environmental Research Theodor Bilharz Research InstituteGizaEgypt

The design of nanostructured materials occupies a privileged position in the development and management of affordable and effective technology in the antibacterial ***,we discuss the antimicrobial properties of three carbonaceous nanoblades and nanodarts materials of graphene oxide(GO),reduced graphene oxide(RGO),and single-wall carbon nanotubes(SWCNTs)that have a mechano-bactericidal effect,and the ability to piercing or slicing bacterial *** demonstrate the significance of size,morphology and composition on the antibacterial activity mechanism,the designed nanomaterials have been *** minimum inhibitory concentration(MIC),standard agar well diffusion,and transmission electron microscopy were utilized to evaluate the antibacterial activity of GO,RGO,and *** on the evidence obtained,the three carbonaceous materials exhibit activity against all microbial strains tested by completely encapsulating bacterial cells and causing morphological disruption by degrading the microbial cell membrane in the order of RGO>GO>*** of the external cell wall structure and outer membrane proteins,the synthesized carbonaceous nanomaterials exhibited higher antibacterial activity against Gram-positive bacterial strains than Gram-negative and fungal *** had the lowest MIC values(0.062,0.125,and 0.25 mg/mL against ***,***,and ***,respectively),as well as minimum fungal concentrations(0.5 mg/mL for both *** and ***).At 12 hr,the cell viability values against tested microbial strains were completely *** lysis and death occurred as a result of severe membrane damage caused by microorganisms perched on RGO *** work gives an insight into the design of effective graphene-based antimicrobial materials for water treatment and remediation.

关键词： Antimicrobial properties Nanoblades Mechano-bactericidal effect RGO nanosheets Gram-positive bacteria Cell viability