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Ultrafast magneto-optical dynamics in nickel(111)single crystal studied by the integration of ultrafast reflectivity and polarimetry probes

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Chinese Physics B 2024年第3期33卷 65-69页

作者：匡皓余军潇陈洁 H.E.Elsayed-ali 李润泽 Peter M.Rentzepis School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Center for Transformative Science ShanghaiTech UniversityShanghai 201210China Center for Ultrafast Science and Technology Key Laboratory for Laser Plasmas (Ministry of Education)Collaborative Innovation Center of IFSA (CICIFSA)School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China department of Electrical and Computer Engineering Old Dominion UniversityNorfolkVirginia 23529USA department of Electrical and Computer Engineering Texas A&M UniversityCollege StationTexas 77843USA

With the integration of ultrafast reflectivity and polarimetry probes,we observed carrier relaxation and spin dynamics induced by ultrafast laser excitation of Ni(111)single *** carrier relaxation time within the linear excitation range reveals that electron-phonon coupling and dissipation of photon energy into the bulk of the crystal take tens of *** the other hand,the observed spin dynamics indicate a longer time of about 120 *** further understand how the lattice degree of freedom is coupled with these dynamics may require the integration of an ultrafast diffraction probe.

关键词： ultrafast spin dynamics non-equilibrium dynamics multi-probe

Modelling of debris-flow susceptibility and propagation: a case study from Northwest Himalaya

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Journal of Mountain Science 2024年第1期21卷 200-217页

作者： Hamza dAUd Javed Iqbal TANOLI Sardar Muhammad ASIF Muhammad QASIM Muhammad ali Junaid KHAN Zahid Imran BHATTI Ishtiaq ahm.d Khan JAdOON Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan 430074China department of Earth Sciences COMSATS University IslamabadAbbottabad Campus 22010Pakistan department of Earth Sciences Sultan Qaboos UniversityAl-KhoudMascat 123Oman Faculty of Engineering China University of Geosciences(Wuhan)Wuhan 430074China department of Earth Sciences Abbottabad University of Science and TechnologyHavelian 22500Pakistan

The geological and geographical position of the Northwest Himalayas makes it a vulnerable area for mass movements particularly landslides and debris flows. Mass movements have had a substantial impact on the study area which is extending along Karakorum Highway(KKH) from Besham to Chilas. Intense seismicity, deep gorges, steep terrain and extreme climatic events trigger multiple mountain hazards along the KKH, among which debris flow is recognized as the most destructive geohazard. This study aims to prepare a field-based debris flow inventory map at a regional scale along a 200 km stretch from Besham to Chilas. A total of 117 debris flows were identified in the field, and subsequently, a point-based debris-flow inventory and catchment delineation were performed through Arc GIS analysis. Regional scale debris flow susceptibility and propagation maps were prepared using Weighted Overlay Method(WOM) and Flow-R technique sequentially. Predisposing factors include slope, slope aspect, elevation, Topographic Roughness Index(TRI), Topographic Wetness Index(TWI), stream buffer, distance to faults, lithology rainfall, curvature, and collapsed material layer. The dataset was randomly divided into training data(75%) and validation data(25%). Results were validated through the Receiver Operator Characteristics(ROC) curve. Results show that Area Under the Curve(AUC) using WOM model is 79.2%. Flow-R propagation of debris flow shows that the 13.15%, 22.94%, and 63.91% areas are very high, high, and low susceptible to debris flow respectively. The propagation predicated by Flow-R validates the naturally occurring debris flow propagation as observed in the field surveys. The output of this research will provide valuable input to the decision makers for the site selection, designing of the prevention system, and for the protection of current infrastructure.

关键词： North Pakistan debris flow Flow-R Propagation Susceptibility mapping debris-flow inventory Weighted Overlay Method

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 Kottakkaran 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

Identification of thermal front dynamics in the northern Malacca Strait using ROMS 3d-model

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Journal of Oceanology and Limnology 2024年第1期42卷 41-57页

作者： Ku Nor Afiza Asnida Ku MANSOR Nur Hidayah ROSELI Poh Heng KOK Fariz Syafiq Mohamad ali Mohd Fadzil Mohd AKHIR Institute of Oceanography and Environment Universiti Malaysia TerengganuKuala Nerus 21030Malaysia Faculty of Science and Marine Environment Universiti Malaysia TerengganuKuala Nerus 21030Malaysia

The thermal front in the oceanic system is believed to have a significant effect on biological *** an era of climate change,changes in heat regulation between the atmosphere and oceanic interior can alter the characteristics of this important *** the simulation results of the 3d Regional Ocean Modelling System(ROMS),we identified the location of thermal fronts and determined their dynamic variability in the area between the southern Andaman Sea and northern Malacca *** Single Image Edge detection(SIEd)algorithm was used to detect the thermal front from model-derived *** show that a thermal front occurred every year from 2002 to 2012 with the temperature gradient at the location of the front was 0.3°C/*** to the years affected by El Ni?o and negative Indian Ocean dipole(IOd),the normal years(e.g.,May 2003)show the presence of the thermal front at every selected depth(10,25,50,and 75 m),whereas El Ni?o and negative IOd during 2010 show the presence of the thermal front only at depth of 75 m due to greater warming,leading to the thermocline deepening and enhanced *** May 2003,the thermal front was separated by cooler SST in the southern Andaman Sea and warmer SST in the northern Malacca *** higher SST in the northern Malacca Strait was believed due to the besieged Malacca Strait,which trapped the heat and make it difficult to release while higher chlorophyll a in Malacca Strait is due to the freshwater conduit from nearby rivers(Klang,Langat,Perak,and Selangor).Furthermore,compared to the southern Andaman Sea,the chlorophyll a in the northern Malacca Strait is easier to reach the surface area due to the shallower thermocline,which allows nutrients in the area to reach the surface faster.

关键词： regional ocean modelling system thermal front Andaman Sea Malacca Strait single image edge detection algorithm

Bond-Slip Behavior of Steel Bar and Recycled Steel Fibre-Reinforced Concrete

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Journal of Renewable Materials 2024年第1期12卷 167-186页

作者： Ismail Shah Jing Li Nauman Khan Hamad R.Almujibah Muhammad Mudassar Rehman ali Raza Yun Peng School of Architecture and Civil Engineering Yunnan Agricultural UniversityKunming650000China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu610041China Yunnan International Joint R&d Center of Smart Agriculture and Water Security Yunnan Agricultural UniversityKunming650201China School of Water Conservancy Yunnan Agricultural UniversityKunming650201China School of Civil Engineering Guizhou UniversityGuiyang550025China department of Civil Engineering College of EngineeringTaif UniversityP.O.Box 11099Taif City21974Saudi Arabia School of Civil Engineering Zhengzhou UniversityZhengzhou450001China

Recycled steel fiber reinforced concrete is an innovative construction material that offers exceptional mechanical properties and *** is considered a sustainable material due to its low carbon footprint and environmental friendly *** study examines the key influencing factors that affect the behavior of this material,such as the steel fiber volume ratio,recycled aggregate replacement rate,concrete strength grade,anchorage length,and stirrup *** study investigates the bond failure morphology,bond-slip,and bond strength constitutive relationship of steel fiber recycled *** results show that the addition of steel fibers at 0.5%,1.0%,and 1.5%volume ratios can improve the ultimate bond strength of pull-out specimens by 9.05%,6.94%,and 5.52%,*** replacement rate of recycled aggregate has minimal effect on the typical bond strength of pull-out ***,the ultimate bond strengths of pull-out specimens with concrete strength grades C45 and C60 have improved compared to those with C30 *** specimens with longer anchorage lengths exhibit lower ultimate bond strength,with a reduction of 33.19%and 46.37%for anchorage lengths of 5d and 7d,respectively,compared to those without *** restraint of 1φ8 and 2φ8 improves the ultimate bond strength by 5.29%and 6.90%,*** fibers have a significant effect on the behavior of concrete after it cracks,especially during the stable expansion stage,crack instability expansion stage,and failure stage.

关键词： Recycled coarse aggregates(RCA) steel fiber bonding performance bond-slip environmental challenges

Exploring the impact of stratification on the dynamics of bioconvective thixotropic fluid conveying tiny particles and Cattaneo-Christov model:Thermal storage system application

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Propulsion and Power Research 2024年第3期13卷 416-432页

作者： T.Oreyeni M.d.Shamshuddin A.M.Obalalu A.Saeed Nehad ali Shah department of Physical Sciences Mathematics Programme UnitPrecious Cornerstone UniversityIbadanNigeria department of Computer Science and Artificial Intelligence(Mathematics) SR UniversityWarangalTelangana State 506371India department of Mathematics Augustine University Ilara EpeLagosNigeria Center of Excellence in Theoretical and Computational Science(TaCS-CoE) Faculty of ScienceKing Mongkut’s University of Technology Thonburi(KMUTT)126 Pracha Uthit Rd.BangModThung KhruBangkok 10140Thailand department of Mathematics and Statistics College of ScienceImam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh 11623Saudi Arabia

Stratified thermal storage promotes energy sustainability by storing excess energy during times of low demand for later use making it possible to integrate renewable energy sources like solar and *** communication discusses the significance of triple stratifica-tion using the Cattaneo-Christov model in the bioconvectiveflow of thixotropicfluid coexisting with nanoparticles and gyrotactic *** Cattaneo-Christov heat and massflux is incorporated into thefluid model allowing more accurate prediction of heat and mass phenomena in thefluid *** governing partial differential equations that describefluidflow are parametrized to yield an ordinary differential equation system by adopting suitable *** series solutions are obtained by applying the homotopy analysis method(HAM).The effects of relevant parameters on the various profiles are revealed and accurately *** is observed that amplified thermal stratification lowers the temperature of ***,Brownian motion is used to illustrate the random movement of small particles suspended in liquids,and it is envisioned that the concentration distribution is significantly influenced by the Brownian motion of nanoparticles.

关键词： Cattaneo-Christov model Stratification Bioconvection Nanofluid

In-cylinder in-depth combustion investigation for a heavy-duty diesel engine

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Propulsion and Power Research 2024年第3期13卷 335-359页

作者： Anam ali Khalid Saifullah Syed Centre for Advanced Studies in Pure and Applied Mathematics(CASPAM) Bahauddin Zakariya University(BZU)MultanPunjab 60800Pakistan

t This present study is part of the design improvement process of a specified high torque low-speed *** work aims at carrying out an in-depth analysis of in-cylinder combustion,mesh sensitivity,and engine performance at supercharge conditions to provide a foundation for the design improvement process of the given *** computational fluid dynamic(CFd)simulations are carried out on a 3d sector from-130°to 130°crank angle(CA)by employing appropriate models to represent the different physical and chemical processes and using the finite volume method for solving the governing differential *** extensive investigation has been carried out for the choice of base mesh size and the number of local and temporal refinements to capture the phenomena happening in the combustion chamber at diverse temporal and local *** present results have been validated against available literature experimental and simulation *** field variables and the wellknown four phases of combustion have been studied for gaining in-depth insight into these *** average pressure,mean temperature,heat release rate(HRR),integrated heat release rate(IHRR),and emissions of CO2,CO,NOx,HC and soot are presented to assess the quality of *** performance analysis has been done in terms of combustion ef-ficiency,gross work,power,torque,and integrated mean effective pressure(IMEP).The base mesh of 1.4 mm may be an appropriate choice during the injection and combustion process spanning throughout around 40CA from the start of injection while in the remaining simulation duration of around 220CA base mesh of 2 mm gives a sufficient *** has been found that maximum heat release takes place in Phase-III,the mixing-controlled phase,of the combustion *** than 98%combustion efficiency has been achieved in all the *** 99%of the total heat release and emissions production takes place within 60CA after top dead center(ATd

关键词： Phases of combustion Heat release rate(HRR) Integrated heat release rate(IHRR) Emissions Performance parameters

Optimizing the utilization of maize silage in forage blends-based rations to improve production performance and reduce methane emissions from fattening calves

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 75-81页

作者： Khalid Farooq Asad Sultan Assar ali Shah Rifat Ullah Khan Rajwali Khan Ghazala Yasmeen Nazir ahm.d Khan Faculty of Animal Husbandry and Veterinary Sciences The University of AgriculturePeshawar 25130Pakistan Pakistan Scientific and Technological Information Center(PASTIC) Islamabad 44000Pakistan

This research investigated the effect of various mixtures of maize silage and ryegrass fodder on nutrient digestibility,production performance,and methane(CH4)emission of fattening ***-four fattening calves((228±10)kg body weight(BW),(280±5)d of age)were allocated to 8 diets for 84 d,according to a randomized complete block design,and the blocks were balanced for BW,age,and *** diets consisted of 4 levels of maize silages,i.e.,40%(MS40),50%(MS50),60%(MS60),and 70%(MS70)in the maize silage and ryegrass fodder mixture on a dry matter(dM)basis,and each of the mixture was supplemented with either low(LC,1.0%BW)or high(HC,1.5%BW)levels of fattening *** results revealed greater(pdM(8.35 kg/d),organic matter(OM,7.85 kg/d),and metabolizable energy(ME,12.00 Mcal/d)in calves fed with MS70-LC *** highest(pdigestibility(g/100 g)of dM(65.2),OM(67.3),crude protein(69.1),and neutral detergent fibre(56.3)was recorded for MS40-HC *** maximum(pdaily gain(AdG,571 g/d)was recorded for diet *** lowest value(pded in MS70-LC,MS70-HC,and MS60-HC as compared to other *** 70%maize silage in the ryegrass-maize silage based diet improved AdG by 174 g/d with LC *** is concluded that the optimum inclusion level of maize silage and ryegrass in the fattening ration can improve animal production performance and reduces CH4 production and concentrate requirements of fattening calves.

关键词： average daily gain farm-grown forages forage mixture fattening calves maize silage ryegrass fodder

An Analysis of the Fragmentation of Observing Time At the Muztagh-Ata Site

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Research in Astronomy and Astrophysics 2024年第3期24卷 29-33页

作者： Wen-Bo Gu Jing Xu Guo-Jie Feng Xuan Zhang Le-Tian Wang Xin-Liang Wang ali Esamdin Li-Xian Shen Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 83001lChina School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

Cloud cover plays a pivotal role in assessing observational conditions for astronomical *** for the fraction of observing time,its fragmentation also wields a significant influence on the quality of nighttime sky *** this article,we introduce the functionΓ∈[0,1],designed to comprehensively capture both the fraction of available observing time and its *** in situ measurement data gathered at the Muztagh-Ata site between 2017 and 2021,we showcase the effectiveness of our *** statistical result illustrates that the Muztagh-Ata site affords approximately 122 nights that were absolutely clear and 205 very good nights annually,corresponding toΓ≥0.9 andΓ≥0.36 respectively.

关键词： site testing-atmospheric effects-methods statistical