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emission colour tuning in KLnF_(4):Yb^(3+),er^(3+)/Ho^(3+)phosphor

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Journal of Rare earths 2024年第1期42卷 57-65,I0002页

作者： Janani K Gayathri e vijayatha v Ramasubramanian S Thiyagarajan P Department of Science and Humanities Nehru Institute of TechnologyKaliapuramThirumalayampalayamCoimbatoreIndia Department of Sciences Amrita School of Physical SciencesAmrita Vishwa VidyapeethamCoimbatoreIndia Department of Physics Anna UniversityChennaiIndia

KLnF_(4):Yb^(3+),er^(3+)/Ho^(3+)(Ln=Y,Yb,Gd)phosphors were prepared by solid-state reaction *** each of the Yb^(3+)/er^(3+)and Yb^(3+)/Ho^(3+)co-doped phosphors independently,phase confirmation and morphological examination were accomplished using the X-ray diffraction technique and scanning electron microscope analysis.X-ray photoelectron spectroscopy analysis shows the charge state and existence of lanthanides and *** luminescence emissions of green and red colour were detected for the synthesized *** changes in the upconverted emission intensities and colour output pertaining to the change of the lanthanide host matrix along with dopants were investigated for the prepared *** the upconversion luminescence,erbium-doped samples exhibit a predominance of red emission while holmium-doped samples display a prevalence of green *** rare-earth er/Ho doped KYbF4shows strong red emission compared to other ***_(4):Yb,er/Ho exhibits relatively significant green upconve rsion emissions,while Yb,er-doped KGdF_(4)host displays a 10-fold increase in green/red emission ratio with an increase in the input power of 20-780 *** photoluminescence studies and decay curve analysis were carried out using Uv light excitation for the developed phosphors.A higher lifetime of 2.2 ms was measured for the downshifting red emission in the Ho doped KYbF_(4)*** study suggests a potential for colour tunability in the upconversion and downshifting emissions through host modifications to the fluoride phosphor.

关键词： Rare earths energy transfer upconversion Downshifting Colour coordinates

Optimizing Spatial Pattern Analysis in Serial Remote Sensing Images through empirical Mode Decomposition and Ant Colony Optimization

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Journal of Harbin Institute of Technology(New Series) 2024年第4期31卷 52-60页

作者： J Srinivasan S Uma Saleem Raja Abdul Samad Jayabrabu ramakrishnan Department of Computer Applications Madanapalle Institute of Technology&Science(MITS)Madanapalle 517325Andhra PradeshIndia Department of Information Technology Panimalar Engineering CollegeChennai 600123India Information Technology Department College of Computing and Information SciencesUniversity of Technology and Applied Sciences-Shinas 324Sultanate of Oman Department of Information Technology and Security College of Computer Science and Information TechnologyJazan UniversityJazan 45142Kingdom of Saudi Arabia

Serial remote sensing images offer a valuable means of tracking the evolutionary changes and growth of a specific geographical area over *** the original images may provide limited insights,they harbor considerable potential for identifying clusters and *** aggregation of these serial remote sensing images(SRSI)becomes increasingly viable as distinct patterns emerge in diverse scenarios,such as suburbanization,the expansion of native flora,and agricultural *** a novel approach,we propose an innovative method for extracting sequential patterns by combining Ant Colony Optimization(ACD)and empirical Mode Decomposition(eMD).This integration of the newly developed eMD and ACO techniques proves remarkably effective in identifying the most significant characteristic features within serial remote sensing images,guided by specific *** findings highlight a substantial improvement in the efficiency of sequential pattern mining through the application of this unique hybrid method,seamlessly integrating eMD and ACO for feature *** study exposes the potential of our innovative methodology,particularly in the realms of urbanization,native vegetation expansion,and agricultural activities.

关键词： spatial pattern analysis eMD ACO

The multi-impurity system in CdSe nanoplatelets:electronic structure and thermodynamic properties

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Communications in Theoretical Physics 2024年第3期76卷 165-173页

作者： D A Baghdasaryan v A Harutynyan e M Kazaryan H A Sarkisyan Russian-Armenian University H Emin 1230051YerevanArmenia Institute of Applied Problems of Physics 25 Nersisyan St0014YerevanArmenia

This paper theoretically studies the impurity states and the effects of impurity concentration and configuration on the optical,electrical,and statistical properties of CdSe nanoplatelets(NPLs).An image charge-based model of electron-impurity interaction is *** charge-carrier energy spectra and corresponding wave functions depending on the impurity number and configuration are *** electron binding energies are calculated for different NPL *** is shown that the image charge-based interaction potential that arises due to the dielectric constants mismatch is much stronger than the interaction potential that does not take such a mismatch into ***,it is demonstrated that the binding energies are increasing with the number of *** calculate the canonical partition function using the energy levels of the electron,which in turn is used to obtain the mean energy,heat capacity,and entropy of the non-interacting electron *** thermodynamic properties of the non-interacting electron gas that depend on the geometric parameters of the NPL,impurity number,configuration,and temperature are studied.

关键词： nanoplateletes thermodynamic properties impurity states

Juvenile survival curves in a solitary ground squirrel with a prolonged hibernation:effects of individual characteristics,environment,and maternal investment

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Current Zoology 2024年第1期70卷 13-23页

作者： Nina A.vasilieva Liudmila e Savinetskaya Andrey v.Tchabovsky A.N.Severtsov Institute of ecology and evolution Russian Academy of SciencesMoscow 119071Russia

Juvenile survival is a key life-history influence on population dynamics and adaptive *** analyzed the effects of individual chara-cteristics,early environment,and maternal investment on juvenile survival in a large solitary hibernating rodent-yellow ground squirrel Spermophilus fulvus using Cox mixed-effects *** 48%of weaned pups survived to dispersal and 17%survived to *** life expectancy was primarily determined by individual characteristics and,to a lesser extent,by the early *** strongest and pos-itive predictor of juvenile survival was body mass which crucially affected mortality immediately after *** suffered higher mortality than females after the onset of dispersal;however,the overall difference between sexes was partly masked by high rates of mortality in the first days after emergence in both *** emerged juveniles had lower life expectancy than the earliest *** overall effect of local juvenile density was *** lactation did not enhance juvenile survival:Pups nursed longer survived shorter than the young nursed for a shorter *** findings support the hypothesis that females of *** cannot effectively regulate maternal expenditures to mitigate the effects of unfavorable conditions on their *** strategy to deal with seasonal time constraints on life history in female *** suggests an early termination of maternal care at the cost of juvenile quality and *** female reproductive strategy corresponds to a"fast-solitary"life of folivorous desert-dwelling *** and other solitary ground squirrels with prolonged hibernation.

关键词： early-life conditions ground squirrels hibernation juvenile mortality maternal investment survival curves

不均匀海底地形影响下柔性板与斜向来浪的相互作用

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哈尔滨工程大学学报（英文版） 2024年第2期23卷 261-275页

作者： Saista Tabssum Balaji ramakrishnan School of Advanced Science-Mathematics VIT-APAmravati744101India Department of Civil engineering Indian Institute of TechnologyBombay 400076India

The present work analyzes the interaction of oblique waves by a porous flexible breakwater in the presence of a step-type *** physical models for both scattering and trapping cases are considered and developed within the framework of small amplitude water-wave ***’s law is used to model the wave interaction with the porous *** is assumed that the varying bottom extends over a finite interval,connected by a finite length of uniform bottom near an impermeable wall,and a semi-infinite length of bottom in the open water *** boundary value problem is solved using the eigenfunction expansion method in the uniform bottom regions,while a modified mild-slope equation(MMSe)is used for the region with the varying ***,a mass-conserving jump condition is employed to handle the solution at slope discontinuities in the bottom.A system of equations is derived by matching the solutions at *** reflection coefficient and force on the breakwater and impermeable wall are plotted and analyzed for various parameters,such as the length of the varying bottom,depth ratio,angle of incidence,and flexural *** is observed that moderate values of flexural rigidity and depth ratio significantly contribute to an optimum reflection coefficient and reduce the wave force on the wall and ***,the outcomes of this study are assumed to be applicable in the construction of this type of breakwater in coastal regions.

关键词： Porous flexible breakwater varying bottom Mild-slope equation Reflection coefficient Wave force

Nanomotion of bacteria to determine metabolic profile

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Nanotechnology and Precision engineering 2024年第1期7卷 1-9页

作者： S.N.Pleskova e.v.Lazarenko N.A.Bezrukov R.N.Kriukov A.v.Boryakov M.e.Dokukin S.I.Surodin Research Laboratory of Scanning Probe Microscopy Lobachevsky State University of Nizhny NovgorodNizhny Novgorod 603950Russia Department of Nanotechnology and Biotechnology Nizhny Novgorod State Technical University n.a.R.E.AlekseevNizhny Novgorod 603950Russia Sarov Physics and Technology Institute National Research Nuclear University MEPhISarov 607186Russia

In addition to their visible motion such as swimming(e.g.,with the help ofﬂagella),bacteria can also exhibit nanomotion that is detectable only with highly sensitive instruments,and this study shows that it is possible to detect bacterial nanomotion using an AFM detection *** results show that the nanomotion characteristics depend on the bacterial strain,and that nanomotion can be used to sense the metabolic activity of bacteria because the oscillations are sensitive to the food preferences of the bacteria and the type of surrounding medium.

关键词： Nanomotion Bacteria Cantilever Oscillation Atomic force microscopy Metabolism

Simple collective model for nuclear chiral mode

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Frontiers of physics 2024年第2期19卷 1-5页

作者： R.v.Jolos e.A.Kolganova D.R.Khamitova Joint Institute for Nuclear Research 141980 DubnaMoscow regionRussia Dubna State University 141982 DubnaMoscow RegionRussia

A simple semi-analytical collective model that takes into account the limitations of the variation interval of the collective variable is suggested to describe the chiral dynamics in triaxial odd−odd nuclei with a fixed particle−hole *** collective Hamiltonian is constructed with the potential energy obtained using the postulated ansatz for the wave function symmetric with respect to chiral *** diagonalizing the collective Hamiltonian the wave functions of the lowest states are obtained and the evolution of the energy splitting of the chiral doublets in transition from chiral vibration to chiral rotation regime is demonstrated.

关键词： collective model nuclear chiral

First results of turbulence investigation on Globus-M2 using radial correlation Doppler reflectometry

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Plasma Science and Technology 2024年第10期26卷 49-55页

作者： A.PONOMAReNKO A.YASHIN v.GUSev e.KISeLev G.KURSKIev v.MINAev Y.PeTROv N.SAKHAROv P.SHCHeGOLev e.TKACHeNKO N.ZHILTSOv Peter the Great St.Petersburg Polytechnic University St.Petersburg 195251Russia Ioffe Institute St.Petersburg 194064Russia

The first results of investigation of the turbulence structure using Doppler backscattering(DBS)on the Globus-M2 tokamak are presented.A one-channel DBS system with a variable probing frequency within the 18–26 GHz range was installed to investigate the edge plasma at normalized minor radiiρ=0.9–*** correlation Doppler reflectometry was used to study the changes in turbulence eddies after the LH *** analysis was applied to the phase derivative of complex in-phase and quadrature(IQ)signals of the DBS diagnostic as it contains information about the poloidal plasma rotation *** L-mode,the radial correlation length L_(r)is estimated to be 3 cm and after transition to H-mode reduces to approximately 2 *** modelling in a linear local approximation using code GeNe indicates that the instability with positive growth rate at the normalized minor radiusρ=0.75 in L-mode and H-mode on Globus-M2 was the ion temperature gradient(ITG)mode.

关键词： tokamak turbulence Doppler backscattering correlation reflectometry

Genetic Basis for Mucormycosis Progression in COvID-19 Patients:From Susceptibility to Severity

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Infectious Diseases & Immunity 2024年第2期4卷 86-92页

作者： Jethendra Kumar Muruganantham ramakrishnan veerabathiran Human Cytogenetics and Genomics Laboratory Faculty of Allied Health SciencesChettinad Hospital and Research InstituteChettinad Academy of Research and EducationKelambakkamTamilnadu 603103India.

The dynamics of COvID-19 and mucormycosis reveal a complex interplay of genetic factors that influence the susceptibility,severity,and immune ***-19,caused by severe acute respiratory syndrome coronavirus 2(SARS-Cov-2),exhibits an increased incidence of mucormycosis,particularly in individuals with comorbidities or corticosteroid *** is a fungal infection that affects the sinuses,orbits,and lungs and demands timely intervention with antifungal medications and surgery because of its life-threatening *** on the genetic underpinnings of this intersection has unveiled key insights into the pathogenicity of *** in genetic tools have exposed virulence factors,such as the CotH protein family and high-affinity iron-uptake *** susceptibility is a pivotal element in identifying individuals at risk of developing COvID-19,facilitating early detection,and allowing for personalized treatment ***9,MIF,and TYK2 are among the genes implicated in COvID-19 severity,emphasizing the intricate relationship between genetic makeup and viral *** genetic landscape extends to viral entry mechanisms,thereby affecting infection *** polymorphisms in genes such as IFNAR2,OAS3,and TYK2 are associated with COvID-19 severity,indicating shared genetic bases between severe and hospitalized *** is genetically predisposed,particularly in immunocompromised *** challenge lies in understanding the genetic factors influencing susceptibility and offering insights into pathogenesis and potential therapeutic *** transplantation adds another layer,increasing susceptibility to infections such as COvID-19 and *** impact of immunosuppression on COvID-19 severity remains elusive,necessitating ongoing research on the immunological *** the challenges posed by emerging SARSCov-2 variants,the intricate connection between genetic factors and the

关键词： COvID-19 Mucormycosis Pathogenesis Genetics basis