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Physical properties and maximum allowable mass-radius relation of complexity-free compact stellar objects within modified f(R,T)gravity formalism

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Chinese Physics C 2024年第7期48卷 273-288页

作者： m.k.Jasim S.k.maurya Abdelghani Errehymy Ali khalid Jassim.k.ttakkaran Sooppy Nisar Abdel-Haleem Abdel-Aty Department of mathematical and Physical Sciences College of Arts and SciencesUniversity of NizwaNizwa 616Sultanate of Oman Astrophysics Research Centre School of MathematicsStatistics and Computer ScienceUniversity of KwaZulu-NatalPrivate Bag X54001Durban 4000South Africa Electrical Engineering Department College of EngineeringMustansiriyah UniversityBaghdadIraq Department of mathematics College of Science and Humanities in AlkharjPrince Sattam bin Abdulaziz UniversityAl KharjSaudi Arabia Department of Physics College of SciencesUniversity of BishaP.O.Box 344Bisha 61922Saudi Arabia

This paper investigates the physical properties and predicted radii of compact stars generated by the Tolman-IV complexity-free model within the background of modified gravity theory,particularly the f(R,T)-gravity theory,under complexity formalism for a spherically symmetric spacetime proposed by ***[Phys Rev D 97:044010,2018].By solving the resulting set of differential equations,we obtain the explicit forms of the energy-momentum(Em)tensor components,including the density,radial pressure,and tangential *** influence of the parameterχon various physical properties of the star is thoroughly *** model undergoes a series of rigorous tests to determine its physical *** findings indicate that the model exhibits regularity,stability,and a surface with vanishing *** boundary of this surface is determined by carefully selecting the parameter *** complexity method employed in f(R,T)gravity offers an interesting approach for developing astrophysical models that are consistent with observable events as demonstrated by recent *** this regard,we use observational data from the GW190814 event,detected by the LIGO and Virgo observatories,to investigate the validity of the Tolman-IV model in f(R,T)*** analysis includes comparing the model's predictions with the observed characteristics of the compact object involved in the *** addition,data from two-millisecond pulsars,PSR J1614-2230 and PSR J0952-0607,are incorporated to further constrain the theoretical ***,we present a diagram depicting the relationship between the total mass and radius of the compact object candidates for different values ofχ.

关键词： complexity modified gravity compact Stars

Hard yet tough and self-lubricating(CuNiTiNbCr)C_(x) high-entropy nanocomposite films:Effects of carbon content on structure and properties

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Journal of materials Science & Technology 2024年第6期173卷 20-30页

作者： Y.T.Li X.m.Chen X.k.Zeng m.Liu X.Jiang Y.X.Leng key Laboratory of Advanced Technologies of materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China key Laboratory of Noise and Vibration Research Institute of AcousticsChinese Academy of SciencesBeijing 100190China State key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China School of mechanical and Electrical Engineering Mianyang Teachers’CollegeMianyang 621000China

The single-phase high-entropy alloy film is difficult to meet severe friction conditions due to its low hardness and high friction ***-composite structure film is composed of at least two separated phases,showing the properties of strength and toughness integration and excellent wear *** design of nanocomposite structures can effectively improve the mechanical properties and tribological properties of high-entropy alloy *** this study,the(CuNiTiNbCr)C_(x) nanocomposite high-entropy films(HEFs)integrated with high hardness,high toughness,and self-lubrication were synthesized by the double-target co-sputtering *** effect of carbon content on microstructure,mechanical properties,and tribological properties of(CuNiTiNbCr)C_(x) films was *** the increase of carbon content in the HEFs,the carbon atoms preferentially react with Ti,Nb,and Cr to form a(TiNbCr)C ceramic-reinforced phase,and then the excess carbon atoms precipitate in the form of amorphous carbon(a-C)lubricating phase in the *** structure of the HEFs changes from an amorphous structure to a nanocomposite structure of amorphous(amorphous CuNiTiNbCr phase+a-C phase)/nanocrystalline(TiN-bCr)C *** the carbon content is about 21.2 at.%,the carbide phase in the film reaches saturation and the hardness and modulus of the films are highest,which are 18 GPa and 228 GPa,*** HEFs with a carbon content of 44.0 at.%show the best toughness and tribological properties with a friction coefficient of 0.16 and a wear rate of 2.4×10^(-6) mm^(3)/(N m),which is mainly attributed to the excellent resistance to fatigue crack growth and the interfacial lubricating layer formed in the friction *** nanocomposite(CuNiTiNbCr)C_(x) HEFs show very promising application prospect in the field of friction protection.

关键词： High-entropy films Nanocomposite Double-target co-sputtering Strengthening-toughening Tribological properties

A new technique for fault diagnosis in transformer insulating oil based on infrared spectroscopy measurements

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High Voltage 2024年第2期9卷 319-335页

作者： mohamed m.F.Darwish mohamed H.A.Hassan Nagat m.k.Abdel-Gawad matti Lehtonen Diaa-Eldin A.mansour Department of Electrical Engineering Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of Electrical Engineering and Automation School of Electrical EngineeringAalto UniversityEspooFinland Department of Electrical Power Engineering Egypt-Japan University of Science and Technology(E-JUST)New Borg El-Arab CityEgypt Department of Electrical Power and machines Engineering Faculty of EngineeringTanta UniversityTantaEgypt

Condition monitoring of the insulating system within power transformers has a massive importance according to the electrical *** gas analysis(DGA)is frequently used for this ***,DGA lacks the necessary level of accuracy to identify all equipment faults,particularly in their initial stages of ***,it does not have the capability for real-time monitoring and relies on manual sampling and laboratory testing,causing potential delays in fault ***,the interpretation of DGA data necessitates specialised expertise,which may pose difficulties for smaller entities that have limited access to ***,the contribution of this research is to use infrared spectroscopy measurements as a new effective technique substituting the DGA method for fault diagnosis in insulating *** inception faults that were considered in this study were the electrical fault(discharges of high energy)and the thermal fault(300°Cmperaturemulation processes inside the laboratory for both types of inception ***,six samples of pure paraffinic mineral oil were taken to be degraded in the *** that,all of them besides another sample that were not subjected to any kind of faults were taken to be examined by Fourier transform infrared(FTIR)spectroscopy to obtain an overview of the oil's behaviour in each fault *** that,the FTIR analysis was initially verified utilising the DGA ***,for further affirmation,the dielectric dissipation factor(DDF)for all samples was *** the final analysis,the verification tests provide experimental evidence about the outperformance of this new optical technique in detecting the transformer's inception faults in addition to proving its potential for being a superior alternative to the well-known traditional diagnostic techniques.

关键词： fault diagnosis spectroscopy

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瞳孔对光反射参数的单侧化

世界核心医学期刊文摘（神经病学分册） 2005年第8期1卷 30-30页

作者： Br k.-J. boettger m.k. Till S. 高中宝 Departmentof Psychiatry Friedrich-Schiller-Univ. Jena Philosophenweg3 07743 Jena Germany

Objective: The aim of this study was to determine differing reactions of the l eft and right eyes with regard to pupillary light reflex (PLR) parameters. metho ds: All together 90 healthy subjects were included. In the first test series, 34 subjects were investigated on both eyes (left eye was tested first, three tests per day and one reliability test). In the second test series, 32 subjects were studied while changing the beginning side. In the last test series, 29 subjects were investigated 12 times each within 1 h (beginning side changed, without spok en advice).Infrared pupillometry was used to study pupil diameter, latency time, relative amplitude, contraction/dilation velocity, and pupil redilation time. R esults: The study demonstrated significant differences of PLR parameters between both eyes. In contrast to the pupil diameter of the left eye the papasympatheti cally dominated right eye was not influenced by vocal instructions or by changin g the beginning side. Conclusions: PLR parameters might indicate functional late ralization of autonomic functionin the central nervous system. High sensitivity of the procedure(arousal due to spoken advice, time of day) is advantageous for various psychophysiological investigations. Significance:Differences between bot h eyes might point towards cortical lateralization of central autonomic function .

关键词：单侧化瞳孔对光反射瞳孔测量法扩张时间健康受试者扩张速度瞳孔反射单侧性自主功能优势侧

Background removal from global auroral images:Data-driven dayglow modeling

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Earth and Planetary Physics 2024年第1期8卷 247-257页

作者： A.Ohma m.madelaire k.m.Laundal J.P.Reistad S.m.Hatch S.Gasparini S.J.Walker Birkeland Centre for Space Science Department of Physics and TechnologyUniversity of BergenBergenNorway

Global images of auroras obtained by cameras on spacecraft are a key tool for studying the near-Earth ***,the cameras are sensitive not only to auroral emissions produced by precipitating particles,but also to dayglow emissions produced by photoelectrons induced by *** emissions and scattered sunlight can contribute to the background *** fully utilize such images in space science,background contamination must be removed to isolate the auroral *** we outline a data-driven approach to modeling the background intensity in multiple images by formulating linear inverse problems based on B-splines and spherical *** approach is robust,flexible,and iteratively deselects outliers,such as auroral *** final model is smooth across the terminator and accounts for slow temporal variations and large-scale asymmetries in the *** demonstrate the model by using the three far ultraviolet cameras on the Imager for magnetopause-to-Aurora Global Exploration(ImAGE)*** method can be applied to historical missions and is relevant for upcoming missions,such as the Solar wind magnetosphere Ionosphere Link Explorer(SmILE)mission.

关键词： aurora dayglow modeling global auroral images far ultraviolet images dayglow removal

Rare earth-doped mixed Ni-Cu-Zn ferrites as an effective photocatalytic agent for active degradation of Rhodamine B dye

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Journal of Rare Earths 2024年第3期42卷 488-496,I0003页

作者： Swapnil A.Jadhav Sandeep B.Somvanshi Sudarshan S.Gawali kranti Zakde k.m.Jadhav Department of Physics Dr.Babasaheb Ambedkar Marathwada UniversityAurangabad431004MaharashtraIndia School of materials Engineering Purdue UniversityWest Lafayette 47906USA University Department of Basic and Applied Sciences MGM UniversityAurangabad431003MaharashtraIndia

In this study, a series of Gd^(3+)-doped mixed Ni-Cu-Zn ferrites with composition of Zn_(0.5)Ni_(0.3)Cu_(0.2)Fe_(2-x)Gd_(x)O_(4)(x = 0, 0.025, 0.05, 0.075, 0.1) was prepared using self-ignition sol-gel method. The prepared nanoparticles with an average size ranging from 22 to 26 nm show a single-phase cubic structure belonging to the spinel matrix. A rise in the Gd^(3+)concentration leads to an increase in crystallite size and lattice parameter. In Fourier transform infrared spectra, two main absorption bands belonging to the spinel structure are observed. The high-frequency bands(v_(1)) represent the tetrahedral complex, while the lowfrequency bands(v_(2)) signify the octahedral complex. The optical bandgap of the nanoferrites is found within the range of 2.91 to 2.41 eV, depending on their size. The magnetic characteristics of the material,such as saturation magnetization and coercivity are significantly altered with the concentration of Gd^(3+)in the solution. Using Rhodamine B(RhB) as a model organic pollutant, an in-depth investigation of the photocatalytic activity of the compounds was carried out. The present outcomes show that adding an adequate amount of Gd^(3+)significantly enhances the number of hydroxyl radicals produced by the ferrite,in turn, increasing the photocatalytic activity of the material. mechanism elucidated by scavenger studies reveals that ·OH and holes are the primary reactive radicals responsible for the degradation *** photocatalysts show an insignificant performance loss in five consecutive cycles. Thus, it is concluded that these photocatalysts are highly suitable for the remediation of dye-contaminated wastewater.

关键词： Gd^(3+)substitution Spinel ferrite Structural properties magnetic properties Photocatalysis Rare earths

Combination treatment of inflammatory bowel disease:Present status and future perspectives

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World Journal of Gastroenterology 2024年第15期30卷 2068-2080页

作者： John k Triantafillidis Constantinos G Zografos manousos m.k.nstadoulakis Apostolos E Papalois Inflammatory Bowel Disease Unit "Metropolitan General"HospitalHolargos 15562AtticaGreece Hellenic Society for Gastrointestinal Oncology 354 Iera OdosChaidari 12461AtticaGreece The 2^(nd)Department of Surgery University of AthensSchool of MedicineAretaieion HospitalAthens 11528Greece Unit of Surgical Research and Training The 2^(nd)Department of SurgeryUniversity of AthensSchool of MedicineAretaieion HospitalAthens 11528Greece

The treatment of patients with inflammatory bowel disease(IBD),especially those with severe or refractory disease,represents an important challenge for the clinical *** seems to be no exaggeration to say that in these patients,not only the scientific background of the gastroenterologist is tested,but also the abundance of“gifts”that he should possess(insight,intuition,determ-ination,ability to take initiative,etc.)for the successful outcome of the *** daily clinical practice,depending on the severity of the attack,IBD is treated with one or a combination of two or more pharmaceutical *** combin-ations include not only the first-line drugs(e.g.,mesalazine,corticosteroids,antibiotics,etc)but also second-and third-line drugs(immunosuppressants and biologic agents).It is a fact that despite the significant therapeutic advances there is still a significant percentage of patients who do not satisfactorily respond to the treatment ***,a part of these patients are going to *** recent years,several small-size clinical studies,reviews,and case reports have been published combining not only biological agents with other drugs(e.g.,immunosuppressants or corticosteroids)but also the combination of two biologi-cal agents simultaneously,especially in severe *** our opinion,it is at least a strange(and largely unexplained)fact that we often use combinations of drugs in a given patient although studies comparing the simultaneous administration of two or more drugs with monotherapy are very *** mentioned above,there is a timid tendency in the literature to combine two biological agents in severe cases unresponsive to the applied treatment or patients with severe extraintestinal *** appropriate dosage,the duration of the administration,the suitable timing for checking the clinical and laboratory outcome,as well as the treatment side-effects,should be the subject of intense clinical research *** this

关键词： Biologics for immune-mediated conditions Dual-targeted treatment Combination treatment Inflammatory bowel disease Crohn’s

Empirical model for fusion cross sections of Ca-induced reactions

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Chinese Physics C 2024年第3期48卷 126-132页

作者： Reddi Rani.L N.Sowmya k.N Sridhar H C.manjunatha m.m.Armstrong Arasu Department of Physics St.Joseph's College(Autonomous)Affiliated to Bharathidasan UniversityTiruchirappalli620002TNIndia Department of Physics Govt.First.Grade CollegeChikkaballapur-562101KarnatakaIndia Department of Physics Govt.First.Grade CollegeMalur-563160KarnatakaIndia Department of Physics Govt.First.Grade CollegeDevanahalli-562110KarnatakaIndia

A new empirical formula for the astrophysical S-factor has been suggested as a function of the Coulomb interaction parameter,center of mass energy,and barrier *** 22 fusion reactions with ^(40,48)Ca as projectiles were considered for different targets,leading to compound nuclei with atomic and mass numbers varying between 40≤Z≤≤Z≤112 and 88≤A≤27888≤A≤278,*** fusion cross-sections have been estimated using the geometric factor,the Gamow-Sommerfield factor,and the empirical formula for the *** study's findings showed better agreement with those of available experiments when compared to Wong's *** present work leads to a smaller standard deviation value than Wong's formula when used to correlate the experimental data of calcium-induced fusion ***'s formula provides a good approximation of fusion cross-sections when the center of mass energy is below the fusion barrier when compared to above the fusion barrier.

关键词： fusion cross-sections Wong formula Gamow-Sommerfield-factor Geometric-factor S-factor

A Comprehensive 3-Steps methodology for Vibration-Based Fault Detection,Diagnosis and Localization in Rotating machines

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Journal of Dynamics, monitoring and Diagnostics 2024年第1期3卷 49-58页

作者： khalid m.Almutairi Jyoti k.Sinha Dynamics Laboratory School of EngineeringThe University of ManchesterManchester M139PLUK

In any industry,it is the requirement to know whether the machine is healthy or not to operate machine *** the machine is not healthy then what is the fault in the machine and then finally its *** paper is proposing a 3-Steps methodology for the machine fault diagnosis to meet the industrial requirements to aid the maintenance *** Step-1 identifies whether machine is healthy or faulty,then Step-2 detect the type of defect and finally its location in *** method is extended further from the earlier study on the 2-Steps method for the rotor defects only to the 3-Steps methodology to both rotor and bearing *** method uses the optimised vibration parameters and a simple Artificial Neural Network(ANN)-based machine Learning(mL)model from the earlier *** model is initially developed,tested and validated on an experimental rotating rig operating at a speed above 1st critical *** proposed method and model are then further validated at 2 different operating speeds,one below 1st critical speed and other above 2nd critical *** machine dynamics are expected to be significantly different at these *** highlights the robustness of the proposed 3-Steps method.

关键词： bearing faults fault diagnosis machine learning rotating machines rotor faults vibration analysis