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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

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

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(ying the high 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

Immediate implantation of ultrafine fiber slow-release system based on cell electrospinning to induce osteogenesis of mesenchymal stem cells

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Regenerative Biomaterials 2024年第2期3卷 76-87页

作者： Tao Lu Long yang Zhuoyang Li yin Liu Shun'en Xu Chuan ye Department of Orthopaedics The Affliated Hospital of Guizhou Medical UniversityGuiyang 550004China Department of Orthopaedics The First People's Hospital of GuiyangGuiyang 550004China Center for Tissue engineering and Stem Cell Research Guizhou Medical UniversityGuiyang 550004China Department of Otolaryngology Head and Neck Surgery Xinqiao HospitalArmy Medical University(Third Military Medical University)Chongqing 400037China Department of Dental implant Stomatological Hospital of GuiyangGuiyang 550000China

This study presents the development and evaluation of a poly(3-hydroxybutyrate-co-4-hydroxybutyrate)(P34HB)ultrafine fiber slow-release system for in vivo osteogenic induction of human umbilical cord mesenchymal stem cells(HUCMSCs).Utilizing dual-nozzle and cell electrospinning techniques,the system encapsulates L-ascorbic acid-2-phosphate magnesium(AsP),βB-glycerophosphate sodium and dexamethasone(DEX)within the'fbers,ensuring sustained osteogenic *** scaffold's morphology,characterization,hydrophilicity,mechanical properties and cellular behavior were *** subcutaneous implantation in rabbits was con-ducted to observe its ectopic osteogenic induction *** fabricated P34HB ultrafine fiber slow-release *** ization *** distribution of HUCMSCs and inducing components within the scaffold,with no chemical reactions affecting the active *** vitro tests showcased a prolonged release of DEX and ASP,while biocompatibility assays highlighted the scaffold's suitability for cellular *** Red,type I collagen,and osteopontin(OPN)staining verifed the scaffold's potent osteogenic induction effect on ***,immediate implantation into New Zealand White rabbits led to significant new bone formation within 8 *** findings underscore the system's potential for immediate in vivo implantation without prior in vitro induction,marking a promising advancement in bone tissue engineering.

关键词： bone tissue engineering cell electrospinning in vivo induction immediate implantation biomaterials

Factors influencing willingness to participate in ophthalmic clinical trials and strategies for effective recruitment

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International Journal of Ophthalmology(english edition) 2024年第1期17卷 157-163页

作者： Jia-en Liang Meng-yin Liang en-en Zhang yu-ying Peng Ling-Ling Chen Jia-yu Deng Ting Lin Jun Fu Jia-Ni Zhang Shao-Li Li Fei Li Hui-Ming Xaio Wen-Min Huang yu-Hong Liu State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangdong Provincial Key Laboratory of Ophthalmology and Visual ScienceGuangdong Provincial Clinical Research Center for Ocular DiseasesGuangzhou 510060Guangdong ProvinceChina

AIM:To explore the factors influencing individuals’willingness to participate in ophthalmic clinical ***:A questionnaire survey was conducted from January to April 2021 among patients and their family members at Zhongshan Ophthalmic Center,Sun yat-sen University,in Guangzhou,*** survey gathered data on respondents’willingness,demographic and socioeconomic profiles,as well as their reasons and concerns regarding engagement in clinical ***:Of the 1078 residents surveyed(mean age 31.2±13.1y;65.8%females)in Guangzhou,749(69.5%)expressed a willingness to participate in future ophthalmic clinical *** characteristics associated with greater willingness included a younger age,lower annual income,higher education,prior participation experience,previous ophthalmic treatment,and a better understanding of clinical *** the exception of age,these characteristics were significantly linked to a higher *** primary barrier to participation,expressed by 64.8%of those willing and 54.4%of those unwilling,was“Uncertain efficacy”.In terms of motivations,the willing group ranked“Better therapeutic benefits”(35.0%),“Professional monitoring”(34.3%),and“Trust in healthcare professionals”(33.1%)as their top three reasons,whereas the unwilling participants indicated“Full comprehension of the protocol”(46.2%)as the key ***:This study reveals a substantial willingness to participate in ophthalmic clinical trials and demonstrates the predictive role of demographic and socioeconomic *** in motivators and concerns between willing and unwilling participants highlight the significance of tailored recruitment ***,the need for and trust in healthcare professionals stand out as powerful motivations,underscoring the importance of enhancing physician-patient relationships,adopting patient-centered communication approaches,and addressing individualized needs to improve accrual rates.

关键词： participation willingness recruitment strategy ophthalmic clinical trial

Ibuprofen-Induced Toxic Epidermal Necrolysis:A Case Report

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International Journal of Dermatology and Venereology 2024年第2期7卷 108-110页

作者： Nevin Kannappilly mohamed Z.Peediyakkal Mohamad y.Khatib Dore C.Ananthegowda Moustafa S.elshafei Hani el Zeer Karimulla S.Shaik Moayad M.AlFayoumi Dyaneshwar P.Mutkule Ahmed A.Soliman Abdulqadir J.Nashwan Critical Care Department Hamad Medical Corporation(HMC)Doha 3050Qatar

Introduction:Toxic epidermal necrolysis(Ten)is a medical emergen.y that most commonly occurs as an adverse effect of certain ***,we describe a case of a 41-year-old man with no comorbid illness who developed *** presentation:The patient had been prescribed ibuprofen for myalgia and developed skin lesions after the single *** lesions were erythematous papules and macules distributed all over the body after ibuprofen *** was diagnosed based on the patient’s clinical presentation and laboratory *** was treated with intravenous dexamethasone,intravenous immunoglobulin,and *** dressing changes and skin care was done with saline,chlorhexidine,and liquid *** patient was intubated and tracheostomized,and he gradually improved and ***,he developed septicemia in the intensive care unit and was treated ***:The management of Ten includes cessation of the causative cause,multidisciplinary intensive care unit(ICU)care,prevention and early detection of sepsis,fluid and electrolyte balance,adequate analgesia and temperature control,proper organ support,aggressive nutritional management,and good psychological *** pharmacological therapy for Ten includes corticosteroids,intravenous immunoglobulin,and *** key elements of management are aseptic care and proper dressing of the ***:Ten is associated with high mortality if not managed in a systemic and protocolized way.

关键词： ibuprofen toxic epidermal necrolysis erythema drug-induced erythema

Treatment of Prostatorectal Fistula by Transanorectal Route: About an Observation

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Open Journal of Urology 2024年第4期14卷 262-266页

作者： mohamed Mahmoud Beya Ahmed Salem Terouzi y. Tfeil Diagana Mouhamadou Urology Department Cheikh Zayed Hospital Nouakchott Mauritania

This is a 54-year-old patient admitted for the management of urinary leakage through the anus that had been occurring for a month, in whom the diagnosis of a prostatorectal fistula was made. The fistula was successful... 详细信息

关键词： Fistula Prostate Rectum york Masson

Mechanical Behavior and Failure Mechanism of an As-Extruded Mg-11wt%y Alloy at elevated Temperature

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Acta Metallurgica Sinica(english Letters) 2024年第6期37卷 969-981页

作者： Lan Zhang Dao-Kui Xu Bao-Jie Wang Cui-Lan Lu Shuo Wang Xiang-Bo Xu Dong-Liang Wang Xin Lv en-Hou Han School of Materials Science and engineering University of Science and Technology of ChinaShenyang110016China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of environmental and Chemical engineering Shenyang Ligong UniversityShenyang110159China Key Lab of electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang110819China Institute of Corrosion Science and Technology Guangdong510070China

Through carrying out the high-temperature tensile experiments on an as-extruded Mg-11wt%y alloy at 350℃,400℃,450℃,500℃and 550℃,the mechanical behavior and fracture mechanisms at elevated temperatures are investigated and *** results show that with the increase of temperature,the yield strength and ultimate tensile strength of the alloy increase at first and then decrease,while that the elongation ratio decreases firstly and then *** the sample being tested at 350℃,the values of yield strength,ultimate tensile strength and the elongation ratio are 188 MPa,266 MPa and 11%,*** 400℃,the yield strength and ultimate tensile strength reach the maximum values of,respectively,198 MPa and 277 MPa,but the elongation ratio is the lowest and its value is only 8%.When the applied temperature is increased to 550℃,the values of yield strength and ultimate tensile strength,respectively,decrease to 140 MPa and 192 MPa and the elongation ratio increases to 38%.Failure analysis demonstrates that the fracture surfaces of different samples are mainly composed of plastic dimples and exhibit the typical characteristic of ductile *** observation to the fracture side surfaces indicates that at the temperatures of 350℃and 400℃,microcracks mainly initiate in the interior of Mg_(24)y_(5)*** the temperatures are 450℃,500℃and 550℃,the cracks preferentially initiate at the Mg_(24)y_(5)/α-Mg interfaces.

关键词： Mg-y alloy High-temperature tensile properties Fracture mechanism Failure analysis

Dynamics of Plate Equations with Memory Driven by Multiplicative Noise on Bounded Domains

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1492-1521页

作者： mohamed y. A. Bakhet Abdelmajid Ali Dafallah Jing Wang Qiaozhen Ma Fadlallah Mustafa Mosa Ahmed Eshag mohamed Paride O. Lolika Makur Mukuac Chinor School of Mathematics University of Juba Juba South Sudan Department of Mathematics Faculty of Petroleum and Hydrology Engineering Alsalam University Almugled Sudan College of Mathematics and Statistics Northwest Normal University Lanzhou China Department of Mathematics and Physics Faculty of Education University of Kassala Kassala Sudan Department of Mathematics School of Education University of Juba Juba South Sudan

This article examines the dynamics for stochastic plate equations with linear memory in the case of bounded domain. We investigate the existence of solutions and bounded absorbing set by using the uniform pullback attractors on the tails estimates, and the asymptotic compactness of the random dynamical system is proved by decomposition method, and then we obtain the existence of a random attractor.

关键词： Plate Equations Random Attractors Memory Term Dynamical Systems

Microstructure and texture evolution of Cu–Cr–Co–Ti alloys during the two-stage cryorolling

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Rare Metals 2024年第9期43卷 4535-4547页

作者： Jia-Jun Zhang Long-Jian Li Zhi-Feng Liu Zong-Ning Chen en.yu Guo Hui-Jun Kang Ren-Geng Li Tong-Min Wang Key Laboratory of Solidification Control and Digital Preparation Technology (Liaoning Province) School of Materials Science and EngineeringDalian University of Technology Center of Hyper-Gravity Experimental and Interdisciplinary Research Zhejiang University Ningbo Institute of Dalian University of Technology！Ningbo315000 China Key Laboratory for Light-Weight Materials Nanjing Tech University

This study entailed an investigation of the mechanical properties, microstructural and texture orientation evolutions of CuDCrDCoDTi alloys prepared via twostage cryorolling and intermediate aging treatment. To this end, X-ray diffraction and electron backscatter diffraction were employed. The results indicate that the two-stage cryorolling and intermediate aging treatments led to the development of profuse twin bundles and significantly enhanced the mechanical properties. The initial cryorolling led to coplanar slip and developed a strong y({111} ) orientation, accelerating the formation of Goss({011} ) orientation and a Brass-type *** intermediate aging treatment relieved the restriction on dislocation slip and reoriented the grains toward the Copper({112} ) and Z({111} ) *** Z orientation, with a relatively high volume fraction,dominated the macrotexture. Secondary cryorolling intensified twinning and shear banding, transforming the Copper-type shear bands into Brass-type shear bands with rhomboidal prism morphology. The areas inside the Brasstype shear bands exhibited a y orientation, and the areas outside the shear bands exhibited a stable Brass-type texture. The evident decrease in the weighted Schmid factors demonstrated that the two-stage cryorolling and intermediate aging treatment can modify the texture evolution and aid the design of high-performance Cu alloys.

关键词： Copper alloys electron backscatter diffraction Macrotexture evolution Schmid factor Two-stage cryorolling