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f(T,B)gravity with statistically fitting of H(z)

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Communications in Theoretical Physics 2023年第9期75卷 79-90页

作者： s H shekh n myrzakulov A Bouali A Pradhan Department of Mathematics S.P.M.Science and Gilani ArtsCommerce CollegeGhatanjiYavatmalMaharashtra 445301India L.n.Gumilyov Eurasian national University Astana 010008Kazakhstan Ratbay myrzakulov Eurasian International Center for Theoretical Physics Astana010009Kazakhstan Laboratory of Physics of Matter and Radiation Mohammed I UniversityBP 717OujdaMorocco Centre for Cosmology Astrophysics and Space Science(CCASS)GLA UniversityMathura-281406Uttar PradeshIndia

some recent developments(accelerated expansion)in the Universe cannot be explained by the conventional formulation of general *** apply the recently proposed f(T,B)gravity to investigate the accelerated expansion of the *** parametrizing the Hubble parameter and estimating the best fit values of the model parameters b_(0),b_(1),and b_(2)imposed from supernovae type la,Cosmic Microwave Background,B aryon Acoustic Oscillation,and Hubble data using the Markov Chain Monte Carlo method,we propose a method to determine the precise solutions to the field *** then observe that the model appears to be in good agreement with the observations.A change from the deceleration to the acceleration phase of the Universe is shown by the evolution of the deceleration *** addition,we investigate the behavior of the statefinder analysis,equation of state(Eos)parameters,along with the energy ***,to discuss other cosmological parameters,we consider some wellknown f(T,B)gravity models,specifically,f(T,B)=aT^(b)+cB^(d).Lastly,we find that the considered f(T,B)gravity models predict that the present Universe is accelerating and the Eos parameter behaves like the ACDM model.

关键词： isotropic homogeneous space-time f(T,B)gravity statistical fitting of H(z)data cosmology

Early Phases of star Formation: Testing Chemical Tools

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Research in Astronomy and Astrophysics 2024年第1期24卷 96-118页

作者： n.C.Martinez s.Paron COnICET-Universidad de Buenos Aires.Instituto de Astronomía y Física del Espacio Ciudad Universitaria(C1428EGA)Ciudad Autónoma de Buenos AiresArgentina

star-forming processes strongly influence the IsM ***,many high-quality databases are available at millimeter *** them,it is possible to carry out studies that review and deepen previous *** these studies involve large samples of sources,it is preferred to use direct tools to study the molecular *** the aim of testing these tools such as the use of the HCn/HnC ratio as a thermometer,and the use of H^(13)CO^(+),HC_(3)n,n_(2)H^(+) and C_(2)H as "chemical clocks," we present a molecular line study toward 55 sources representing massive young stellar objects at different evolutionary stages:infrared dark clouds(IRDCs),highmass protostellar objects(HMPOs),hot molecular cores(HMCs) and ultracompact H II *** found that the use of the HCn/HnC ratio as a universal thermometer in the IsM should be taken with care because the HCn optical depth is a big issue that can affect the ***,this tool should be utilized only after a careful analysis of the HCn spectrum,checking that no line,neither the main nor the hyperfine ones,presents absorption *** point out that the analysis of the emission of H^(13)CO^(+),HC_(3)n,n_(2)H^(+) and C_(2)H could be useful to trace and distinguish regions among IRDCs,HMPOs and *** molecular line widths of these four species increase from the IRDC to the HMC stage,which can be a consequence of the gas dynamics related to the starforming processes taking place in the molecular *** results not only contribute with more statistics,acting as a probe of such chemical tools,useful to obtain information in large samples of sources,but also complement previous works through the analysis of other types of sources.

关键词： stars:formation IsM:molecules IsM:clouds

Chloride binding and time-dependent surface chloride content models for fly ash concrete

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Frontiers of structural and Civil Engineering 2016年第1期10卷 112-120页

作者： s. MUTHULInGAM B. n. RAO Department of Civil Engineering SSN College of Engineering Kalavakkam 603 110 India structural Engineering Division Department of Civil Engineering Indian Institute of Technology Madras Chennai 600 036 India

Corrosion of embedded rebars is a classical deterioration mechanism of reinforced concrete structures exposed to chloride environments. such environments can be attributed to the presence of seawater, deicing or sea-salts, which have high concentrations of chloride ion. Chloride ingress into concrete, essential for inducing rebar corrosion, is a complex interaction between many physical and chemical processes. The current study proposes two chloride ingress parameter models for fly ash concrete, namely： 1） surface chloride content under tidal exposure condition; and 2） chloride binding. First, inconsistencies in surface chloride content and chloride binding models reported in literature, due to them not being in line with past research studies, are pointed out. secondly, to avoid such inconsistencies, surface chloride content and chloride binding models for fly ash concrete are proposed based upon the experimental work done by other researchers. It is observed that, proposed models are simple, consistent and in line with past research studies reported in literature.

关键词： binding isotherms chloride ingress concrete fly ash surface chloride content

Comprehensive investigation of stress intensity factors in rotating disks containing three-dimensional semi-elliptical cracks

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Applied Mathematics and Mechanics(English Edition) 2017年第11期38卷 1565-1578页

作者： M.FAKOOR s.M.n.GHOREIsHI Faculty of new sciences and Technologies University of Tehran Tehran 14395-1561 Iran

Initiation and propagation of cracks in rotating disks may cause catastrophic failures. Therefore, determination of fracture parameters under different working con- ditions is an essential issue. In this paper, a comprehensive study of stress intensity factors （sIFs） in rotating disks containing three-dimensional （3D） semi-elliptical cracks subjected to different working conditions is carried out. The effects of mechanical prop- erties, rotational velocity, and orientation of cracks on sIFs in rotating disks under cen- trifugal loading are investigated. Also, the effects of using composite patches to reduce sIFs in rotating disks are studied. The effects of patching design variables such as mechanical properties, thickness, and ply angle are investigated separately. The modeling and analytical procedure are verified in comparison with previously reported results in the literature.

关键词： stress intensity factor (sIF) semi-elliptical crack rotating disk finite ele-ment analysis (FEA)

comseedling growth of five tropical dry forest tree species in relation to light and nitrogen gradients

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Journal of Plant Ecology 2014年第3期7卷 250-263页

作者： s.n.Tripathi A.s.Raghubanshi Ecosystems Analysis Laboratory Department of BotanyBanaras Hindu UniversityVaranasiUttar Pradesh 221005India Deen Dayal Upadhyaya College University of DelhiShivaji MargKarampuraNew Delhi 110015India Institute of Environment and sustainable Development Banaras Hindu UniversityVaranasiUttar Pradesh 221005India

Aims Increasing anthropogenic nitrogen(n)deposition has been claimed to induce changes in species composition and community dynamics.A greenhouse experiment was conducted to examine the effect of increased n availability on growth and functional attributes of seedlings of five tree species with different life history characteristics under varying *** following questions have been addressed:(i)how do the pioneer and non-pioneer species respond in absolute growth and relative growth rate(RGR)to the interaction of light and nitrogen?(ii)how does the interaction between irradiance and nitrogen availability modulate growth attributes(*** attributes)?(iii)is there any variation in growth responses between leguminous and non-leguminous species along the light and nitrogen gradients?Methods seedlings of five tree species(Acacia catechu,Bridelia retusa,Dalbergia sissoo,Lagerstroemia parviflora and Terminalia arjuna)were subjected to twelve combinations of irradiance and n *** growth traits,including height(HT),basal area(BA),whole plant dry biomass(MD),leaf mass per unit area(LMA),leaf area ratio(LAR),net assimilation rate(nAR),RGR,biomass fractions,root-toshoot ratio(R:s)and leaf nitrogen content,were studied to analyse intra-and inter-specific responses to interacting light and n *** Findings significant interactions for irradiance and n availability for majority of growth attributes indicates that growth and biomass allocation of seedlings were more responsive to n availability under high ***,species responded differentially to n addition and they did not follow successional *** growers(***,a shade-tolerant species and ***,a light demander)exhibited greater response to n enrichment than the fast growers(***,*** and ***).However,n-mediated increment in growth traits was greater in non-legumes(***,*** and ***)compared with that of legumes(*** and D

关键词： tropical dry forest irradiance nitrogen biomass allocation relative growth rate net assimilation rate

structural and photoluminescence properties of La3+ doped CdO nanophosphors synthesised via green mediated solution combustion route

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Journal of Rare Earths 2019年第9期37卷 916-923,I0001页

作者： M.s. Geetha H.n. shivananjaiah Vijaya Composite College Bangalore560 003India Government science College Nrupatunga RoadBangalore 560 001India

This paper reports a facile environmentally safe green combustion synthesis method of La3+doped CdO nanoparticles(nPs)using different concentrations of Aloe vera(A.V)gel as combustible *** crystallite size obtained using PXRD pattern is found to be 12-22 *** structural analysis was further analysed by Rietveld refinement *** X-ray photoelectron spectroscopy(XPs)analysis reveals the presence of two electronic states of CdO around 400 and 411 eV attributed to Cd 3 d3/2 and 3 d3/2,*** photoluminescence(PL)studies were carried upon 350 nm excitation *** PL emission spectra are found to have two prominent peaks centered at 410 and 510 nm and are attributed to 5D3→7F1 and 5D1→7F0 transitions,*** Commission International de l’Eclairage(CIE)chromaticity diagram reveals blue-green color *** correlation color temperature(CCT)value is found to be around^9793 *** obtained results suggest that the product is quite useful for cool light emitting diode applications when doping concentration is 2 mol%.

关键词： Green synthesis nanostructures Photoluminescence Judd-ofelt Rare earths CdO

Comparative assessment of mechanical and chemical fluid diversion techniques during hydraulic fracturing in horizontal wells

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Petroleum science 2023年第6期20卷 3582-3597页

作者： Maunish s.shah subhash n.shah Drilling Cementingand Stimulation Research CenterDepartment of Petroleum EngineeringSchool of Energy TechnologyPandit Deendayal Energy UniversityRaisanGandhinagarGujaratIndia Mewbourne school of Petroleum and Geological Engineering The University of OklahomaNormanOKUSA

The application of fluid diversion during hydraulic fracturing is an evolving technology and has become popular amongst E&P operators over the past few *** primary objective of the fluid diversion is to improve hydraulic fracturing treatment by increasing stimulated reservoir volume and improving hydrocarbon *** is possible by achieving any of the following objectives:creating uniform distribution of treatment slurry within the target zone;treating unstimulated and under-stimulated zones;or by increasing fracture density by creating a complex fracture *** fluid diversion application is also helpful in decreasing the number of stages(by increasing stage length)for multi-stage plug-n-perf(PnP)fracturing *** is also applied to prevent fracture-driven interactions between adjacent wells,which is currently a major issue,especially in *** addition,for successful refracturing treatment,the diverter application is essential for isolating the existing fractures and redirecting the treatment slurry to the desired unstimulated *** diversion methods can be broadly categorized into the mechanical and chemical *** established mechanical diversion techniques are frac plugs,expandable casing patches,expandable liners,swellable packers,straddle packer assembly,sand plugs,frac sleeves,perforation ball sealers,and limited entry *** different chemical diversion techniques are particulates,fibers,gels,surfactants,perforation pods,and composite *** paper describes the current status of established mechanical and chemical diverter technologies and examines their comparative advantages and *** techniques are suitable for diverter application,but the technique is selected based on the desired objective and conditions of the wellbore and *** general guidelines for selecting diversion techniques and operational considerations are also provided in the *** diagnosis of diversion treatme

关键词： Fluid diversion Diverter Diverting agents Multi-stage fracturing Hydraulic fracturing Horizontal well

Mat hematical modeling and analysis of innate and humoral immune responses to dengue infections

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International Journal of Biomathematics 2019年第7期12卷 95-110页

作者： sulanie Perera s.s.n.Perera Research and Development Center for Mathematical Modeling Faculty of ScienceUniversity of ColomboColombo 3Sri Lanka

Dengue is an acute arthropode-borne virus,belonging to the family ***,there are no vaccines or treatments available against *** it is important to understand the dynamics of dengue in order to control the *** this paper,we study the long-term dynamics of the model that is presented in[*** and ***,simulation model for dynamics of dengue with innate and humoral immune responses,*** Med.2018(2018)8798057,18 ***:10.1155/2018/8798057]which describes the interaction of virus with infected and uninfected cells in the presence of innate and humoral immune *** was found the model has three equilibria,namely:infection free equilibrium,no immune equilibrium and endemic equilibrium,then analyzed its stability *** analytical findings of each model have been exemplified by numerical *** the fact that intensity of dengue virus replication at early times of infection could determine clinical outcomes,it is important to understand the impact of innate immunity,which is believed to be the first line of defense against an invading *** this we carry out a simulation case study to investigate the importance of innate immune response on dengue virus dynamics.A comparison was done assurming that innate immunity was active;innate immunity was in quasi-steady state and innate immunity was inactive during the virus replication *** a further analysis of the qualitative behavior of the quasi-steady state,it was observed that innate immune response plays a pivotal role in dengue virus *** can change the dynamical behavior of the system and is essential for the virus clearance.

关键词： Dengue humoral inate equilibrium stability quasi-steady state

Combustion synthesis of Ce^(3+), Eu^(3+) and Dy^(3+) activated naCaPO_4 phosphors

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Journal of Rare Earths 2011年第6期29卷 527-535页

作者： K n shinde s J Dhoble Animesh Kumar Department of Physics RTM Nagpur University national Environmental Engineering Research Institute

The preparation of naCaPO4 doped with rare earth （RE） ions Ce3＋, Eu3＋ and Dy3＋ by combustion method was described. Under UV excitation （251 nm） of naCaPO4：Ce3＋ showsd emission （367 nm） in UV range. When naCaPO4：Dy3＋ phosphor was excited at 349 nm, the emission spectrum showed intense bands at 482 nm （blue） and 576 nm （yellow）. In Eu activated naCaPO4 phosphor, the emission spectrum showed a dominant peak at 594 nm （orange） while others were at 614 and 621 nm （red） when excited at 393 nm. The prepared phosphor was characterized by X-ray diffraction （XRD）, scanning electron microscope （sEM） and photoluminescence （PL） measurement. Thus, the photoluminescence behavior of naCaPO4：Ce3＋ was strongly suggested for scintillator. Likewise, Eu3＋ and Dy3＋ activated naCaPO4 phosphors were recommended for near-UV white light-emitting diodes （LEDs）.

关键词： combustion synthesis photoluminescence phosphor scintillator solid state lighting rare earths