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cool white light and tunable multicolor emission from Tb^(3+)/Dy^(3+)co-activated glasses under different excitations for WLEDs

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Journal of Rare Earths 2024年第1期42卷 46-56,I0002页

作者： L.Vijayalakshmi k.Naveen kumar Jong Dae Baek Department of Automotive Engineering Yeungnam UniversityGyeongsanGyeongbuk38541Republic of Korea Department of Mechanical Engineering Yeungnam UniversityGyeongsan38541Republic of Korea

A set of co-doped(Tb^(3+)/Dy^(3+))lithium zinc borate(LZB)glasses were developed by melt *** structural evaluation was performed for synthesized glassy *** Dy^(3+)and Tb^(3+)individually doped glasses exhibit intense yellow and green luminescence bands at 575 nm(^(4)F_(9/2)→^(6)H_(13/2))and543 nm(^(5)D_(4)→^(7)F_(5)),*** sensitization effect of Dy^(3+)on Tb^(3+)was analyzed by increasing the Tb^(3+)content with respect to the optimum Dy^(3+)content(0.5 mol%)in Dy^(3+)/Tb^(3+).The spectral overlay of Dy^(3+)luminescence and Tb^(3+)absorption profiles,Dy^(3+)/Tb^(3+)PL spectra under different excitations 352,362,376,and 385 nm,shortening decay lifetimes of Dy^(3+)in Dy^(3+)/Tb^(3+)co-activated glasses,energy transfer(ET)parameters,chromaticity coordinates and their corresponding correlated temperatures all help to explain ET from Dy^(3+)to Tb^(3+).At 385 nm of Dy^(3+)excitation,the optimized co-activated(0.5Dy^(3+)+1.0Tb^(3+)):LZB glass displays cool white light *** non-radiative ET from Dy^(3+)to Tb^(3+)is dominated by electric dipole-dipole interaction and its ET efficiency was calculated to be 63%.At the same time,reverse ET from Tb^(3+)to Dy^(3+)was also *** shift in color coordinates from dominant yellow to greenish-yellow,green and white light emission suggests that Dy^(3+)/Tb^(3+)coactivated LZB glasses can be a potential candidate for UV converted multicolor and white light emitting devices.

关键词： Rare earths Photoluminescence Energy transfer Spectral overlap Decay lifetime Multicolor emitting LEDs

The diagnostic conundrum in necrotizing otitis externa

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第1期10卷 59-65页

作者： Abiya A.Ahmed Shaan Rashid Vinay k.Gupta Neil c.Molony keshav k.Gupta Bradford Royal Infirmary Bradford Teaching Hospitals NHS Foundation TrustWest BromwichWest YorkshireUK Sandwell and West Birmingham Hospitals NHS Trust West BromwichUK Russells Hall Hospital DudleyUK

Necrotizing otitis externa(NOE)is an aggressive and fast‐evolving infection of the external auditory *** diagnoses and untreated cases can lead to severe,even fatal consequences and so early diagnosis and treatment are *** is a notoriously challenging diagnosis to *** is therefore important to understand what diagnostic modalities are available and how otolaryngologists can use them to accurately treat such an aggressive *** review aims to evaluate the different diagnostic options available in NOE and discuss their advantages and limitations,thus,providing an up‐to‐date picture of the multimodal approach required in the diagnosis of this disease.

关键词： diagnostic malignant otitis externa necrotizing osteomyelitis skull base osteomyelitis temporal bone osteomyelitis

Thermal properties and high-temperature ablation of high-entropy (Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) coating on graphite substrate

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Journal of Advanced ceramics 2024年第8期13卷 1268-1281页

作者： Ana c.Feltrin Daniel Hedman Farid Akhtar Division of Materials Science Lulea University of TechnologyLulea 97187Sweden center for Multidimensional carbon Materials(cMcM) Institute for Basic Science(IBS)Ulsan 44919Republic of Korea

An entropy-stabilized multicomponent ultrahigh-temperature ceramic(UHTc)coating,(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2),on a graphite substrate was in-situ sintered by spark plasma sintering(SPs)from constituent transition metal diboride ***(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) coating had a hardness of 31.2±2.1 GPa and resisted 36.9 GPa of stress before delamination,as observed at the *** temperature-dependent thermal properties of the multicomponent diboride(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) were obtained by molecular dynamics(MD)simulations driven by a machine learning force field(MLFF)trained on density functional theory(DFT)*** thermal conductivity,density,heat capacity,and coefficient of thermal expansion obtained by the MD simulations were used in time-dependent thermal stress finite element model(FEM)*** low thermal conductivity(k^(-1))of the multicomponent diboride coupled with its similar coefficient of thermal expansion to that of graphite indicated that stresses of less than 10 GPa were generated at the interface at high temperatures,and therefore,the coating was mechanically resistant to the thermal stress induced during *** experiments at 220℃ showed that the multicomponent diboride coating was resistant to thermal stresses with no visible cracking or *** ablation mechanisms were mechanical denudation and evaporation of B_(2)O_(5) and light V-Ti oxides,which caused a decrease in the mass and thickness of the coating and resulted in mass and linear ablation rates of-0.51 mg·s^(-1) and -1.38μm·s^(-1),respectively,after 60 *** findings demonstrated the thermal and mechanical stability of multicomponent entropy-stabilized diborides as coatings for carbon materials in engineering components under extreme environments.

关键词： entropy-stabilized diborides ultrahigh temperature ceramics molecular dynamics(MD)simulations density functional theory(DFT) ablation properties

Thermal conductivity suppression in uranium-doped thorium dioxide due to phonon-spin interactions

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Journal of Materiomics 2024年第3期10卷 709-715页

作者： Zilong Hua Saqeeb Adnan Amey R.khanolkar karl Rickert David B.Turner Timothy A.Prusnick J.Matthew Mann David H.Hurley Marat khafizov cody A.Dennett Materials Science and Engineering Department Idaho National LaboratoryIdaho FallsID83415USA Department of Mechanical and Aerospace Engineering The Ohio State UniversityColumbusOH43210USA kBR DaytonOH45431USA Azimuth corporation FairbornOH45324USA Air Force Research Laboratory Wright-Patterson AFBOH45433USA Department of Nuclear Science and Engineering Massachusetts Institute of TechnologyCambridgeMA02139USA

In this work,impact of low level of uranium(U)atom substitution on thermal conductivity of thorium dioxide(ThO_(2))is ***_(2)is an electronic insulator with a wide optical band-gap and no unpaired electrons whose thermal transport is governed by phonons.U-substitution introduces unpaired f-electrons resulting in paramagnetic behavior of UeThO_(2)at room temperature,which significantly suppresses its thermal conductivity.A single crystal of UeThO_(2)with graded composition of U is grown using a hydrothermal synthesis method,and thermal conductivity measurements are performed in re-gions with uniform composition of U at levels of 0%,6%,9%and 16%.Measured thermal conductivity profiles over 77e300 k temperature range are analyzed using an analytical expression for phonon-mediated thermal transport based on klemens-callaway *** dependent thermal con-ductivity is found to deviate significantly from the Rayleigh scattering trend expected for a simple substitutional point defect with a small perturbation to mass and interatomic *** the resonant scattering term,observed large suppression of thermal conductivity at low temperatures can be closely ***,the extracted phonon-spin coupling constants imply a nonlinear relation of phonon-spin interaction intensity with respect to U doping *** study reveals how phonon-spin scattering contributed by unpaired f-electrons in U atoms influences thermal transport in the UeThO_(2)system.

关键词： Phonon-spin interactions Thermal conductivity UdThO_(2)system

Anti-obesity effects of fucoidan from Sargassum thunbergii in adipocytes and high fat diet induced obese mice through inhibiting adipogenic specific transcription factor

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Food Science and Human Wellness 2024年第3期13卷 1608-1616页

作者： Hyo-Geun Lee H.H.A.c.k.Jayawardhana Fengqi Yang D.P.Nagahawaththa N.M.Liyanage kyung-Mo Song Yun-Sang choi Seung-Hong Lee You-Jin Jeon Min-cheol kang Department of Marine Life Sciences Jeju National UniversityJeju 63243Republic of Korea Marine Science Institute Jeju National UniversityJeju 63333Republic of Korea Research Group of Food Processing Korea Food Research InstituteWanju 55365Republic of Korea Department of Pharmoceutical Engineering Soonchunhyang UniversityAsan 31538Republic of Korea

The prevalence of obesity has increased and is a health concern *** to the concerns regarding synthetic anti-obesity treatments,nowadays natural products become a *** studies proved that there is a potential to use marine algae as anti-obesity ***,in this study,the lipid inhibitory effect of crude polysaccharide of amyloglucosidase-assisted hydrolysate from Sargassum thunbergii(STAc)and its fucoidan fractions(STAFs)on 3T3-L1 cells and high-fat diet(HFD)-induced obese mice were *** to the results,the STAF3,showed the highest xylose content and exhibited significant inhibitory effects on lipid accumulation by downregulating adipogenic and lipogenic proteins in 3T3-L1 ***,oral supplementation with STAc significantly declined gain in body weight and fat weight,and serum lipid contents in an HFD-induced obesity mouse *** and chemical characterizations demonstrated that puritied STAF3 has consistent surface morphology and small particle size,with similar structural characteristics as commercial ***,these results indicate that STAc and purified STAF3 from Sargassum thunbergia is a potent source to develop as ananti-obesity agents or functional food products to counter obesity.

关键词： Sargassum thunbergii Fucoidan Anti-obesity Anti-steatosis

Pelvic fractures in blunt trauma patients:A comparative study

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World Journal of Orthopedics 2024年第5期15卷 418-434页

作者： Alexander A Fokin Joanna Wycech knight Madison E Tharp kyler c Brinton Phoebe k Gallagher Justin Fengyuan Xie Russell D Weisz Ivan Puente Trauma and critical care Services Delray Medical CenterDelray BeachFL 33484United States charles E Schmidt college of Medicine Department of SurgeryFlorida Atlantic UniversityBoca RatonFL 33431United States Trauma and critical care Services Broward Health Medical CenterFort LauderdaleFL 33316United States charles E Schmidt college of Medicine Florida Atlantic UniversityBoca RatonFL 33431United States Herbert Wertheim college of Medicine Department of SurgeryFlorida International UniversityMiamiFL 33199United States

BAckGROUND Pelvic fractures(PF)with concomitant injuries are on the rise due to an increase of high-energy *** of the elderly population with age related comorbidities further complicates the *** organ injuries are kindred with PF due to the proximity to pelvic *** of contrast blush(cB)on computed tomography in patients with PF is considered a sign of active bleeding,however,its clinical significance and association with outcomes is *** To analyze polytrauma patients with PF with a focus on the geriatric population,co-injuries and the value of contrast *** This retrospective cohort study included 558 patients with PF admitted to level 1 trauma center(01/2017-01/2023).Analyzed variables included:Age,sex,mechanism of injury(MOI),injury severity score(ISS),Glasgow coma scale(GcS),abbreviated injury scale(AIS),co-injuries,transfusion requirements,pelvic angiography,embolization,laparotomy,orthopedic pelvic surgery,intensive care unit and hospital lengths of stay,discharge disposition and *** study compared geriatric and non-geriatric patients,patients with and without cB and abdominal *** score matching was implemented in comparison *** PF comprised 4%of all trauma admissions.89 patients had cB.286(52%)patients had concomitant injuries including 93(17%)patients with abdominal *** patients compared to non-geriatric had more falls as MOI,lower ISS and AIS pelvis,higher GcS,less abdominal co-injuries,similar cB and angio-embolization rates,less orthopedic pelvic surgeries,shorter lengths of stay and higher *** propensity matching,orthopedic pelvic surgery rates remained lower(8%vs 19%,Pc *** of 89 patients with cB,45(51%)were *** propensity matching,patients with cB compared to without cB had more pelvic angiography(71%vs 12%,P<0.001),hi

关键词： Pelvic fractures Geriatric trauma patients Abdominal co-injuries contrast blush contrast extravasation Angioembolization Polytrauma patients Surgical interventions Blunt trauma External and internal fixation for pelvic stabilization

Structural,morphological,optical and antibacterial performances of rare earth(Sm)-doped ZnO nanorods

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Journal of Rare Earths 2024年第11期42卷 2119-2127页

作者： A.Ravi J.Samuel S.Sahaya Jude Dhas S.Usharani Turibius Simon D.Senthil kumar S.k.Jasmin Vijitha A.Sivakumar Raju Suresh kumar c.S.Biju Department of Physics University College of Engineering Department of Physics and Research centre Malankara Catholic College Manonmaniam Sundaranar University Saveetha School of Engineering Saveetha Institute of Medical and Technical SciencesSaveetha University Department of chemistry S.I.V.E.T College Department of Biotechnology Vivekanandha College of Arts and Science for Woman (Autonomous) Department of Physics Vel Tech Rangarajan Dr.Sagunthala R & D Institute of Science and Technology Department of Physics & Research centre Muslim Arts College key Laboratory of High-temperature and High-pressure Study of the Earth's Interior Institute of GeochemistryChinese Academy of Sciences Department of chemistry College of ScienceKing Saud University Department of Physics St. Alphonsa College of Arts and Science

The significant rise of ultra-violet（UV） radiation and pathogenic infectious bacteria poses a serious threat to global *** researchers' interests are attracted by novel materials with strong UVblocking ability,antibacterial activity and low toxicity to other *** this case,a simple wet chemical method with different annealing temperatures（400,500,and 600℃） was employed to create highly effective rare earth（Sm）-doped ZnO ***（101） plane of wurtzite ZnO shifts towards a lower angle with increasing annealing temperature,according to the X-ray diffraction（XRD） study findings,which additionally establishes the consequence of lattice *** of doublet peaks of Sm 3d(Sm 3d5/2and Sm 3d3/2) in the X-ray photoelectron spectroscopy（XPS） spectrum clearly validates the substitution of Sm3+ions in the 500℃-annealed *** 500℃-annealed nanorods exhibit combined performances of the wide band gap,improved UV absorbance,and vivid green luminescent emission（563 nm）.Additio nally,the nanorods have favorable UV-blocking execution of 96% for UVA at 360 nm,92% for UVB at 320 nm,and 57% for UVc at 225 nm,which is greater than the majority of ZnO-related materials that have been reported up to this *** doping is also appropriate for improving bacterial inhibition against the two studied strains（Escherichia coli and Staphylococcus aureus）,in addition to the intriguing features discussed ***,with maximum inhibition zone diameters of 20±0.72 and 18±0.57 mm,respectively,these nanorods exhibit high inhibitory action against *** and *** bacterial *** rare earth-doped material developed during the current experiment,which was annealed at 500℃,could potentially serve as an effective replacement for UV-blocking and antibacterial material,especially for biomedical applications.

关键词： Wet chemical method rare earth doping Metal oxide UV-Shielding Bacterial inhibition

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： c.Y.Morassuti A.P.L Silva L.A.O.Nunes S.M.Lima L.H.c.Andrade Optical and Photothermal Spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 k is 3.00%/k,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

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