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Synthesis, Crystal Structure and Antibacterial Activity of.1-((2-Chloroquinolin-3-yl)-methyl)-pyridin-2(1H)-one

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Chinese Journal of.Structural Chemistry 2010年第11期29卷 1612-1617页

作者： S. Mohana Roopan Venkatesha R. Hathwar f. Nawaz khan Atul Kumar Kushwaha Organic & Medicinal Chemistry Research Laboratory Organic Chemistry Division School of Advanced Sciences VIT University Solid State and Structural Chemistry Unit Indian Institute of Science

On the basis of.the interesting structures and biological activities exhibited by several heterocyclic systems possessing the pyridone nucleus such as mappcine and camptothecin, we have planed to design the synthesis, crystal studies and antibacterial activity of.the new 1-（（2- chloroquinolin-3yl）-methyl）-pyridine-2（1H）-one building block. An X-ray analysis has provided valuable insight into the ef.ect of.steric f.ctors on the three-dimensional shape of.this compound which serves as a usef.l advanced intermediate in the synthesis of.these biologically active molecules. A multistep synthesis of.camptothecin （5） has been designed by retrosynthetic analysis as part of.an ongoing program on lead anticancer drug.

关键词： crystal structure 1-((2-chloroquinolin-3yl)-pyridine-2(1H)-one

Nickel-Phosphorus Deposition on Pretreated Aluminium Alloys during Immersion in Electroless Nickel Bath

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材料科学与工程（中英文A版） 2011年第4X期1卷 457-471页

作者： Chike f. Oduoza Enam khan University of.Wolverhampton School of Engineering & Built Environment SC-040 Telford Campus Priorslee Telford TF2 9NTShropshire United Kingdom

Study of.Structural, Electrical and Magnetic Properties of.Manganese Doped Cobalt f.rrite Nanoparticles with Non-stoichiometric Composition

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Journal of.Physical Science and Application 2017年第6期7卷 30-37页

作者： M. Z. Ahsan f. A. khan Department of.Physics Military Institute of Science and Technology (MIST) Dhaka-1216 Bangladesh Department of.Physics Bangladesh University of Engineering and Technology (BUET) Dhaka-1000 Bangladesh

The nanoparticles of.Co1＋xMnxf.2-xO4 （0≤x ≤ 0.5） f.rrite system are synthesized by solid-state reaction route using planetary ball milling technique to investigate structural, electrical and magnetic properties. The X-ray dif.raction patterns conf.rm the inverse spinel structure with residual oxide phases. Three distinct regions of.f.equency response on dielectric constant are observed Co1.2sMn0.5f.1.75O4 as determined by the Wayne Kerr Impedance Analyzer. The f.rst two regions of.f.equency response 1.13-4.5 MHz and 4.5-6.5 MHz exhibit the normal behavior but the last region 6.5-10.5 MHz indicates its anomalous behavior due to concurrent contribution of.O^2-, f.^3＋, Co^2＋ and Mn^3＋ ions in the relaxation process f.r sintering ef.ects （sintered at 700℃）. This anomalous behavior is f.und to be pronounced and signif.cant f.r the sample of.composition Co1.25Mn0.25f.1.75O4, which may be suitable to be used in the f.equency band f.lter over wide range of.f.equencies. The single peak of.imaginary part of.dielectric constant （ε＂） indicates that the conduction process in this sample is due to the grain boundary resistance. The pronounced increase of.capacitance （C） as observed f.om 100 ℃ to 125 ~C in temperature dependent measurement （30-125℃） is expected to eause f.om the change of.polarization across the grain boundary due to redistribution of.ions by the thermal agitation. The variation of.resistance （R） with temperature （30-125 ℃） is f.und to exhibit semieonducting behavior that resulted f.om the p-type carriers （Co^2＋/Co^3＋）. A signif.cant increase of.Z f.om 105 ℃ with the increase of.temperature indicates the signature of.phase transition f.om f.rrimagnetic-to-f.rromagnetic, which may be ascribed to the increase of.Co content. The appearance of.the single semicircular arc in the Cole-Cole plot may be attributed to the contribution of.grain boundary resistance and correspond to the parallel equivalent circuit of.resistor-capacitor （R-C） combination with single relaxatio

关键词： Cobalt f.rrite dielectric constant capacitance resistance impedance cole-cole plot magnetization.

Modeling and Comprehensive Review of.Signaling Storms in 3GPP-Based Mobile Broadband Networks:Causes,Solutions,and Countermeasures

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 123-153页

作者： Muhammad Qasim khan f.zal Malik f.had Alturise Noor Rahman Department of.Computer Science Iqra National UniversityPeshawar25000Pakistan Department of.Cybersecurity College of ComputerQassim UniversityBuraydah52555Saudi Arabia Department of.Computer Science and Engineering Al-Fayha CollegeAl Jubayl31961Saudi Arabia

Control signaling is mandatory f.r the operation and management of.all types of.communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband ***,they consume important and scarce network resources such as bandwidth and processing *** have been several reports of.these control signaling turning into signaling storms halting network operations and causing the respective Telecom companies big f.nancial *** paper draws its motivation f.om such real network disaster incidents attributed to signaling *** this paper,we present a thorough survey of.the causes,of.the signaling storm problems in 3GPP-based mobile broadband networks and discuss in detail their possible solutions and *** provide relevant analytical models to help quantif. the ef.ect of.the potential causes and benef.ts of.their corresponding *** important contribution of.this paper is the comparison of.the possible causes and solutions/countermeasures,concerning their ef.ect on several important network aspects such as architecture,additional signaling,f.delity,etc.,in the f.rm of.a *** paper presents an update and an extension of.our earlier conf.rence *** our knowledge,no similar survey study exists on the subject.

关键词： Signaling storm problems control signaling load analytical modeling 3GPP networks smart devices diameter signaling mobile broadband data access data traf.ic mobility management signaling network architecture 5G mobile communication

Comparative study of.living donor kidney transplants:Right vs lef.

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World Journal of.Transplantation 2025年第1期15卷 115-123页

作者： Taqi khan Nadeem Ahmad Qaisar Iqbal Muneeb Hassan Lajward Asnath Naveed khan Sajid Shakeel Kidney Transplant Unit Rehman Medical InstitutePeshawar 25100Khyber PakhtunkhwaPakistan Department of.Surgery Princess Noura Binti AbdulRehman UniversityRiyadh 84428Saudi Arabia

BACKGROUND Transplant teams of.en hesitate to use the right kidney(RK)in living donor(LD)transplants due to the complexities of.anastomosing the short,thin-walled right renal veins,which can potentially lead to graf. loss or graf. ***,circumstances may arise where selecting the RK over the lef. kidney(LK)is ***,it is crucial to thoroughly examine the implications of.such a choice on the overall transplant *** To compare transplant outcomes between recipients of.RK and LK while examining the f.ctors that inf.uence these *** We retrospectively analyzed data f.om adult patients who received LD kidney transplants involving meticulous patient selection and surgical techniques at our center f.om January 2020 to December *** included all kidney donors who were over 18,f.t to donate,and had undergone diethylenetriamine pentaacetic acid split f.nction and/or computed tomography based *** variables examined comprised donor and recipient demographics,and outcome measures included technical graf. loss(TGL),delayed or slow graf. f.nction(SGf.,and post-transplant serum creatinine(SC)*** used a logistic regression model to assess the likelihood of.adverse outcomes considering the donor kidney *** Of.the 250 transplants perf.rmed during the period,56(22%)were *** recipient demographics and transplant f.ctors were comparable f.r the right and LKs,except that the donor warm and cold ischemia time were shorter f.r *** and SGf.each occurred in 2%(n=1)of.RKs and 0.5%(n=1)of.LKs,the dif.erence being *** complications,however,were not related to the venous *** RK(2%)developed delayed graf. f.nction af.er 48 hours,which was attributable to postoperative hypoxia rather than the surgical *** post-transplant SC trend and mean SC at the last f.llow-up were similar across both kidney *** The donor kidney side has little impact on post-transplant

关键词： Living donor Right kidney Right renal vein Venous anastomosis Technical graf. loss Early graf. f.nction

Exploring Nanoscale Perovskite Materials f.r Next‑Generation Photodetectors:A Comprehensive Review and f.ture Directions

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Nano-Micro Letters 2025年第2期17卷 46-108页

作者： Xin Li Sikandar Af.ab Maria Mukhtar f.hmid Kabir Muhammad f.rooq khan Hosameldin Helmy Hegazy Erdi Akman State Key Laboratory of.Pulsed Power Laser Technology National University of Defense TechnologyHefei 230037AnhuiPeople’s Republic of China Anhui Laboratory of.Advanced Laser Technology Hefei 230037AnhuiPeople’s Republic of China Nanhu Laser Laboratory Changsha 410015HunanPeople’s Republic of China Department of.Semiconductor Systems Engineering and Clean Energy Sejong UniversitySeoul 05006Republic of Korea Department of.Artif.cial Intelligence and Robotics Sejong UniversitySeoul 05006Republic of Korea School of.Engineering Science Simon Fraser UniversityBurnabyBC V5A 1S6Canada Department of.Electrical Engineering Sejong UniversitySeoul 05006South Korea Department of.Physics Faculty of ScienceKing Khalid UniversityP.O.Box 9004AbhaSaudi Arabia Central Labs King Khalid UniversityAlQura’aP.O.Box 96061413 AbhaSaudi Arabia Scientif.c and Technological Research and Application Center Karamanoglu Mehmetbey University70100 KaramanTurkey

The rapid advancement of.nanotechnology has sparked much interest in applying nanoscale perovskite materials f.r photodetection *** materials are promising candidates f.r next-generation photodetectors(PDs)due to their unique optoelectronic properties and f.exible synthesis *** review explores the approaches used in the development and use of.optoelectronic devices made of.dif.erent nanoscale perovskite architectures,including quantum dots,nanosheets,nanorods,nanowires,and *** a thorough analysis of.recent literature,the review also addresses common issues like the mechanisms underlying the degradation of.perovskite PDs and of.ers perspectives on potential solutions to improve stability and scalability that impede widespread *** addition,it highlights that photodetection encompasses the detection of.light f.elds in dimensions other than light intensity and suggests potential avenues f.r f.ture research to overcome these obstacles and f.lly realize the potential of.nanoscale perovskite materials in state-of.the-art photodetection *** review provides a comprehensive overview of.nanoscale perovskite PDs and guides f.ture research ef.orts towards improved perf.rmance and wider applicability,making it a valuable resource f.r researchers.

关键词： Nanoscale perovskites Photodetectors Nanosheets Nanorods Nanowires Quantum dots Nanocrystals

Optimization of.gob ventilation boreholes design in longwall mining

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International Journal of.Mining Science and Technology 2020年第6期30卷 811-817页

作者： Saqib Ahmad Saki Jürgen f.Brune Muhammad Usman khan University of.Engineering and Technology Lahore Lahore 54890Pakistan Colorado School of.Mines GoldenCO 80401USA

Gob ventilation boreholes(GVBs)are widely used f.r degasif.cation in *** coal *** on geological conditions,30–50%of.methane can be recovered f.om longwall gob using GVBs.A NIOSH f.nded research at the Colorado School of.Mines conf.rmed that GVBs can ef.iciently reduce methane at the ***,GVBs can also draw some f.esh air f.om the f.ce and create explosive gas zones(EGZs).Explosive gas mixtures may be f.rmed in gob areas due to the increased ingress of.oxygen f.om *** is critical to identif. the locations f.r GVBs f.r maximizing extraction of.methane and minimizing hazards of.*** study analyzes the ef.ect of.operating parameters and design of.GVB on methane extraction,EGZs f.rmation,and f.ce and tailgate methane *** extraction,f.rmation of.EGZs,and concentration of.methane in working areas are signif.cantly impacted by various *** f.ctors include the distance of.work f.ce and tailgate f.om GVBs,diameter of.GVBs,vacuum pressure of.wellhead,GVB distance f.om the roof.of.the coal seam,and number of.operating GVBs in a *** f.uid dynamics(Cf.)evaluations suggest optimal design and operating parameters of.GVBs that can contribute to maximum benef.ts with minimum risks.

关键词： Longwall mining Explosive gas zones Computational f.uid dynamics Gob ventilation boreholes

Rare earth element(REE) geochemistry of.phosphorites of.the Sonrai area of.Paleoproterozoic Bijawar basin,Uttar Pradesh,India

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Journal of.Rare Earths 2012年第5期30卷 507-514页

作者： K.f.khan Shamim A.Dar Saif.A.khan Department of.Geology Aligarh Muslim UniversityAligarh-202002Uttar PradeshIndia

The rare earth element（REE） data f.om the Paleoproterozoic Bijawar basin,Sonrai phosphorites were used to interpret the depositional conditions of.the *** post archean Australian shales（PAAS） normalized REE patterns of.the Sonrai phosphorites were characterized by negative Ce and positive Eu *** rare earth elements（MREE）-enrichment was a characteristic *** showing the diagenetic ef.ects on the REE patterns were *** observed Eu anomaly was indicative of.an anoxic（or sulphate reducing） diagenetic environment of.phosphate *** of.sea water and upwelling during the Paleoproterozoic was responsible f.r the recording of.positive Eu and negative Ce anomalies in the Sonrai phosphorites.

关键词： rare earth elements geochemistry phosphorites Sonrai Bijawar basin Ce anomaly Eu anomaly

Transportation of.heat through Cattaneo-Christov heat f.ux model in non-Newtonian f.uid subject to internal resistance of.particles

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Applied Mathematics and Mechanics(English Edition) 2020年第8期41卷 1157-1166页

作者： M.I.khan f.ALZAHRANI Department of.Mathematics Riphah International UniversityFaisalabad 38000Pakistan Nonlinear Analysis and Applied Mathematics(NAAM)-Research Group Department of MathematicsFaculty of SciencesKing Abdulaziz UniversityJeddah 21589Saudi Arabia

Thermal conduction which happens in all phases(liquid,solid,and gas)is the transportation of.internal energy through minuscule collisions of.particles and movement of.electrons within a working *** colliding particles comprise electrons,molecules,and atoms,and transf.r disorganized microscopic potential and kinetic energy,mutually known as the internal *** engineering sciences,heat transf.r comprises the processes of.convection,thermal radiation,and sometimes mass ***,more than one of.these procedures may happen in a given *** use the Cattaneo-Christov(CC)heat f.ux model instead of.the f.urier law of.heat conduction to discuss the behavior of.heat transportation.A mathematical model is presented f.r the Cattaneo-Christov double dif.usion(CCDD)in the f.ow of.a non-Newtonian nanof.uid(the Jef.rey f.uid)towards a stretched *** magnetohydrodynamic(MHD)f.uid is *** behaviors of.heat and mass transportation rates are discussed with the *** models are based on f.urier’s and f.ck’s *** convective transportation in nanof.uids is discussed,subject to thermophoresis and Brownian *** nonlinear governing f.ow expression is f.rst altered into ordinary dif.erential equations via appropriate transf.rmations,and then numerical solutions are obtained through the built-in-shooting *** impact of.sundry f.ow parameters is discussed on the velocity,the skin f.iction coef.icient,the temperature,and the concentration *** is reported that the velocity of.material particles decreases with higher values of.the Deborah number and the ratio of.the relaxation to retardation time *** temperature distribution enhances when the Brownian motion and thermophoresis parameters *** concentration shows contrasting impact versus the Lewis number and the Brownian motion *** is also noticed that the skin f.iction coef.icient decreases when the ratio of.the relaxation to retarda

关键词： Cattaneo-Christov double dif.usion(CCDD) non-Newtonian f.uid model(Jef.rey model) viscous dissipation magnetohydrodynamic(MHD) Brownian dif.usion thermophoresis dif.usion