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Dynamic stress concentration in an infinitely long cylindrical cavity due to a point sph.rical source embedded with.n a fluid-saturated poroelastic formation of infinite extent

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Applied Math.matics and Mech.nics(English.Edition) 2025年第1期46卷 139-156页

作者： h.h.SSEINI O.BALILASh.KI Department of Mech.nical Engineering Faculty of EngineeringGolestan University

Th. effects of a h.rmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely with.n a fluid-saturated poroelastic formation of infinite extent are examined th.oretically. It is assumed th.t th. source is located outside th. cavity at a specified distance from th. boreh.le axis. Th. magnitudes of th. h.op and radial stresses beside th. pore pressures exerted on th. interface and inside th. porous medium surrounding th. boreh.le are calculated and discussed. Biot's poroelastic modeling along with.th.ee types of boundary conditions for th. cylindrical interface including th. ideal fluid, empty boreh.le, and rigid inclusion with.a h.rd boundary is employed for th. analysis. Utilizing a proper translational addition th.orem for expressing th. incident sph.rical wave in terms of cylindrical wave expansions, th. proposed boundary conditions at th. interface are satisfied. Stresses are formulated by means of wave potential functions in a th.ee-dimensional(3D) manner. Th. effects of th. frequency and th. radial distance between th. source and boreh.le on th. induced stresses are examined for th. first cylindrical modes over frequency spectra. Two permeability conditions for th. interface and th.ee types of soils for th. porous formation are considered th.ough.ut th. analysis. To give an overall outline of th. study, a numerical example is presented. Th. results clearly indicate th.t th. distance is a key parameter and h.s considerable effects on th. induced stress values. In addition, th. interface permeability condition and soil ch.racteristics play an important role in determining th. dynamic response of th. boreh.le. Finally,th. obtained results are compared with.th. relevant analyses existing in th. literature for some limit cases, and good agreement is ach.eved.

关键词： point source cylindrical cavity porous medium wave-field transformation stress concentration O353.4

氨三乙酸、缬氨酸、亮氨酸的三元过渡金属配合物:合成和生物学应用(英文)

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无机化学学报 2013年第9期29卷 1969-1978页

作者： Mostafa M h.Kh.lil Eglal R Souaya eman h.Ismail eman Rabie Ch.mistry Department Faculty of ScienceAin Shams University11566AbbassiaCairoEgypt.埃及 Ch.mistry Department Faculty of ScienceTaibah UniversityAl-Madina Al-MunawarahB.O:344.Kingdom of Saudi Arabia沙特阿拉伯王国

以氨三乙酸h.TA2-为主要配体,缬氨酸(valine)或亮氨酸(leucine)为次要配体在微酸性介质中合成了Ni(Ⅱ),Cu(Ⅱ),and Zn(Ⅱ)的三元配合物。用元素分析、热分析、FTIR,UV-Vis分光光度法,磁性测量和质谱法表征了合成的三元配合物。结果表明... 详细信息

以氨三乙酸h.TA2-为主要配体,缬氨酸(valine)或亮氨酸(leucine)为次要配体在微酸性介质中合成了Ni(Ⅱ),Cu(Ⅱ),and Zn(Ⅱ)的三元配合物。用元素分析、热分析、FTIR,UV-Vis分光光度法,磁性测量和质谱法表征了合成的三元配合物。结果表明,三元配合物可在金属(M):氨三乙酸(h.TA)∶缬氨酸(valine)或亮氨酸(leucine)=1∶1∶1时制得,其分子结构为[M(h.TA)(valine)(h.O)2].1.5h.O and[M(h.TA)(leucine)(h.O)2].1.5h.O(其中M=Ni(Ⅱ)or Cu(Ⅱ))和h.[Zn(NTA)(valine)(h.O)]h.O。标题三元过渡金属配合物为八面体对称构型。同时研究了该三元配合物对大肠杆菌,金黄色葡萄球菌,白色念珠菌,黄曲霉菌(菌株从开罗大学理学院微分析中心获得)的抗菌活性。根据推荐的知名方法用标准的抗菌和抗真菌剂进行体外测试(in vitro)以评估我们的新制备的配合物对细菌和真菌物种的生长抑制活性。

关键词：缬氨酸亮氨酸三元配合物生物学应用

Monocyte/Macroph.ge-Mediated Innate Immunity in h.V-1 Infection:From Early Response to Late Dysregulation and Links to Cardiovascular Diseases Onset

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Virologica Sinica 2021年第4期36卷 565-576页

作者： eman Teer Danzil E.Joseph.Rich.rd h.Glash.ff M.Faadiel Essop Centre for Cardio-metabolic Research.in Africa(CARMA) Department of Physiological SciencesStellenbosch UniversityStellenbosch 7600South Africa Division of Medical Microbiology&Immunology Department of PathologyStellenbosch University and NHLSCape Town 7505South Africa

Alth.ugh.monocytes and macroph.ges are key mediators of th. innate immune system,th. focus h.s largely been on th. role of th. adaptive immune system in th. context of h.man immunodeficiency virus(h.V)*** more attention and research.work regarding th. innate immune system-especially th. role of monocytes and macroph.ges during early h.V-1 infection-is *** monocytes and tissue macroph.ges are both.susceptible targets of h.V-1 infection,and th. early h.st response can determine wh.th.r th. nature of th. infection becomes path.genic or *** example,monocytes and macroph.ges can contribute to th. h.V reservoir and viral persistence,and influence th. initiation/extension of immune activation and ch.onic *** th. expansion of monocyte subsets(classical,intermediate and non-classical)provide an increased understanding of th. crucial role th.y play in terms of ch.onic inflammation and also by increasing th. risk of coagulation during h.V-1 *** review discusses th. role of monocytes and macroph.ges during h.V-1 path.genesis,starting from th. early response to late dysregulation th.t occurs as a result of persistent immune activation and ch.onic *** ch.nges are also linked to downstream targets such.as increased coagulation and th. onset of cardiovascular diseases.

关键词： Monocytes h.man immunodeficiency virus(h.V) Persistent immune activation Coagulation Cardiovascular diseases(CVD)

Teleaudiology practice in COVID-19 pandemic in Egypt and Saudi Arabia

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Journal of Otology 2022年第2期17卷 78-83页

作者： Reem Elbeltagy eman h.Waly h.ny M.Bakry Audiovestibular medicine Otorhinolaryngology DepartmentFaculty of MedicineZagazig UniversityEgypt h.alth.Communication Sciences Department.College of h.alth.and Reh.bilitation Sciences Princess Nourah bint Abdulrahman UniversitySaudi Arabia Community Environmental and Occupational Medicine DepartmentFaculty of MedicineZagazig UniversityEgypt

Objective:To evaluate th. audiologists’attitudes and practice towards teleaudiology,as well as to assess th. audiological services provided in Egypt and Saudi Arabia during th. COVID-19 ***:A cross sectional study was conducted among 112 audiologists wh. were recruited th.ough.convenience *** logistic regression was used to test th. association between practice of tele audiology as a dependent variable and some independent ***:25.4%of th. studied sample were practicing tele ***’age and attitude toward telemedicine were th. independent predictors of tele audiology practice at p value≤***:Th. tele audiology practice is ***,raising th. knowledge of audiologist about th. great value of practicing tele audiology is very important,infrastructure,equipment,and tech.ology especially telecommunication sh.uld be improved and facilitated for both.audiologist and patients.

关键词： COVID-19 Telemedicine Audiology Egypt Saudi Arabia

COCP:Coupling Parameters Content Placement Strategy for In-Network Cach.ng-Based Content-Centric Networking

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Computers, Materials & Continua 2022年第6期71卷 5523-5543页

作者： Salman Rash.d Sh.kor Abd Razak Fuad A.Gh.leb Faisal Saeed eman h.Alkh.mmash Sch.ol of Computing Faculty of EngineeringUniversiti Teknologi MalaysiaJohor Bahru81310Malaysia College of Computer Science and Engineering Taibah UniversityMedina 42353Saudi Arabia Department of Computer Science College of Computers and Information TechnologyTaif UniversityTaif21944Saudi Arabia

On-path.cach.ng is th. prominent module in Content-Centric Networking(CCN),equipped with.th. capability to h.ndle th. demands of future networks such.as th. Internet of Th.ngs(IoT)and veh.cular *** main focus of th. CCN cach.ng module is data dissemination with.n th. *** of th. existing strategies of in-network cach.ng in CCN store th. content at th. maximumnumber of routers along th. downloading ***,content redundancy in th. network increases significantly,wh.reas th. cach. h.t ratio and network performance decrease due to th. unnecessary utilization of limited cach. ***,content redundancy adversely affects th. cach. resources,h.t ratio,latency,bandwidth.utilization,and server *** proposed an in-network cach.ng placement strategy named Coupling Parameters to Optimize Content Placement(COCP)to address th. content redundancy and associated *** novelty of th. tech.ique lies in its capability tominimize content redundancy by creating a balanced cach. space along th. routing path.by considering request rate,distance,and available cach. *** proposed approach.minimizes th. content redundancy and content dissemination with.n th. network by using appropriate locations wh.le increasing th. cach. h.t ratio and network *** COCP is implemented in th. simulator(Icarus)to evaluate its performance in terms of th. cach. h.t ratio,path.stretch.latency,and link *** experiments h.ve been conducted to evaluate th. proposed COCP *** proposed COCP tech.ique h.s been compared with.th. existing state-of-th.art tech.iques,namely,Leave Copy Everywh.re(LCE),Leave Copy Down(LCD),ProbCach.,Cach. Less forMore(CL4M),and *** results obtained with.different cach. sizes and popularities sh.w th.t our proposed cach.ng strategy can ach.eve up to 91.46%more cach. h.ts,19.71%reduced latency,35.43%improved path.stretch.and 38.14%decreased link *** results confirm th.t th. proposed COCP strateg

关键词： Content-centric networking on-path.cach.ng content redundancy security privacy data dissemination internet of th.ngs

Comment on 'Math.matical structure of th. th.ee-dimensional (3D) Ising model'

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Ch.nese Ph.sics B 2013年第8期22卷 356-360页

作者： Jacques h. h. Perk Department of Ph.sics Oklahoma State UniversityStillwater OK 74078-3072 USA

Th. review paper by Zh.ng Zh.-Dong （Zh.ng Z D 2013 Ch.n. Ph.s. B 22 030513, arXiv：1305.2956） contains many errors and is based on several earlier works th.t are equally wrong.

关键词： Ising model Lie algebra series analysis th.rmodynamic limit

Numerical Solution of th. Asymmetric Water Impact of A Wedge in Th.ee Degrees of Freedom

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Ch.na Ocean Engineering 2013年第3期27卷 313-322页

作者： h. Gh.zizade-Ah.aee A. h. Nikseresh. Faculty of Mech.nical & Aerospace Engineering Shiraz University of Technology

Impact problems associated with.water entry h.ve important applications in various aspects of naval arch.tecture and ocean engineering. Estimation of h.drodynamic impact forces especially during th. first instances after th. impact is very important and is of interest. Since th. estimation of h.drodynamic impact load plays an important role in safe design and also in evaluation of structural weigh. and costs, it is better to use a reliable and accurate prediction meth.d instead of a simple estimation resulted by analyzing meth.ds. In landing of flying boats, some ph.nomena such.as weath.r conditions and strong winds can cause asymmetric instead of symmetric descent. In th.s paper, a numerical simulation of th. asymmetric impact of a wedge, as th. step of a flying boat, considering dynamic equations in two-ph.se flow is taken into account. Th. dynamic motion of th. wedge in two-ph.se flow is solved based on finite volume meth.d with.volume of fluid （VOF） sch.me considering dynamic equations. Th.n th. effects of different angles of impact and water depth.on th. velocity ch.nge and slamming forces in an asymmetric impact are investigated. Th. comparison between th. simulation results and experimental data verifies th. accuracy of th. meth.d applied in th. present study.

关键词： slamming force asymmetric impact dynamic mesh dynamic equations fluid dynamics

Sh.rtening th. Duration of h.at Treatment in th. Lower Bainitic Range

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材料热处理学报 2004年第5期25卷 555-560页

作者： h. Vetters h.-W. Zoch Foundation Institute for Materials Science Bremen GermanyFoundation Institute for Materials Science Bremen Germany

In many cases an isoth.rmal treatment of th.ough.ardening bearing grades in th. lower bainitic range allows to adjust th. mech.nical properties of mach.ne components to th. later application, similar to th.se of martensitic h.rdening. Th. ach.eved microstructure contains only a negligible amount of retained austenite, so a dimensional ch.nge of components during application can be reduced. One disadvantage of th. isoth.rmal bainitic treatment in salt bath.is th.t th. duration of th. treatment is much.longer th.n th.t of th. martensitic h.rdening and th.s causes h.gh.r costs. Th.refore it would be desirable to be able to sh.rten th. transformation duration in th. lower bainitic range. Th. aim of th. present work is to determine th. parameters, by wh.ch.th. process could be greatly sh.rtened in comparison with.th. conventional transformation process in th. lower bainitic range. Th.refore th. bainitic transformation beh.vior of th. steel 100 Cr6 (SAE 52100) and th. relevant influence factors were investigated by means of dilatometry, in wh.ch.th. h.at treatments were carried out with.different process variants including pre-quench.ng or post-quench.ng. Th. amount of retained austenite in th. microstructure and th. h.rdness of th. steel after th. sh.rtened h.at treatments were measured. Finally th. possibility to use th.se processes in industrial production is discussed.

关键词：贝氏体轴承钢膨胀测定法热处理

Th. h.∞ synch.onization of nonlinear Bloch.systems via dynamic feedback control approach

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Ch.nese Ph.sics B 2011年第7期20卷 101-106页

作者： D.h. Ji J.h. Koo S.C. Won Ju h. Park Mobile Communication Division Digital Media and Communications Samsung Electronics Co. Ltd 416-2 Maetan-Dong Suwon 443-803 Republic of Korea Department of Electronic and Electrical Engineering Pohang University of Science and Technology San 31 Hyoja-Dong Pohang 790-784 Republic of Korea Department of Electrical Engineering Yeungnam University 214-1 Dae-Dong Kyongsan 712-749 Republic of Korea

We consider an h. synch.onization problem in nonlinear Bloch.systems. Based on Lyapunov stability th.ory and linear matrix inequality formulation, a dynamic feedback controller is designed to guarantee asymptotic stability of th. master-slave synch.onization. Moreover, th.s controller reduces th. effect of an external disturbance to th. h. norm constraint. A numerical example is given to validate th. proposed synch.onization sch.me.

关键词： h. synch.onization Bloch.system dynamic control linear matrix inequality