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Late corneal ectasia after penetrating and deep anterior lamellar keratoplasty for keratoconus

International Journal of Ophthalmology(English edition) 2024年第10期17卷 1828-1836页

作者： Bora Yüksel Arife Esra Kocakaya Tuncay Küsbeci Fatih gümüş Department of Ophthalmology University of Health SciencesIzmir Bozyaka Education and Research HospitalIzmir 35110Türkiye

AIm:To investigate tomographic features of late corneal ectasia after keratoplasty for keratoconus and compare penetrating keratoplasty(PK)and deep anterior lamellar keratoplasty(DALK)in terms of incidence,time of onset and risk factors of corneal ***:Sixty eyes with PK and 30 eyes with DALK operated between 1999 and 2021 were *** Pentacam scans were evaluated together with vision and previous *** outcome measures were vision,K values,apparent thinning on graft-host cornea and the difference between opposing quadrants in the thinnest point *** segment optic coherence tomography was performed for further ***:mean follow-up was 127.2mo(24–282mo)in PK,and 64.3mo(24–144mo)in DALK.K max was higher in DALK(60.6 vs 56.7 D,P=0.012).Inferior recipient was thinner(595.9μm)in PK than DALK(662.2μm,P=0.021),due to longer *** corneal ectasia rate was 20.0%within *** rate was the same(6.7%)in DALK 2/30 and in PK 4/60 in 10y and 13.3%in 12y(4/30 and 8/60,respectively).It increased to 23.3%(14/60)in PK over *** ectasia was not seen before 7y in PK,it could be seen in DALK starting from the 5^(th) *** intervals between keratoplasty and ectasia were 144.5mo in PK and 99mo in *** recipient was significantly thinner in 18 eyes with ectasia(502.7μm)compared to 76 non-ectasia(649.1μm,P=0.000).Inferior graft was thinner(561.0 vs 620.4μm,P=0.006),K max(63.3 vs 56.5 D,P=0.000),and anterior elevation was higher in ectasia(89.1 vs 48.6μm,P=0.002).Accelerated crosslinking was performed on 5 ***:Inferior-superior recipient and inferior graft thinning on tomography,with high K max and anterior elevation emerge as the most reliable criteria for the diagnosis of late *** incidence of corneal ectasia increases with the time.

关键词： keratoconus penetrating keratoplasty deep anterior lamellar keratoplasty corneal ectasia

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Facile synthesis of samarium and cerium doped double perovskite cobaltite with enhanced dielectric response

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Journal of Rare Earths 2024年第7期42卷 1317-1327,I0005页

作者： Yasir Abbas m.Kamran m.Anis-ur-Rehman Applied Thermal Physics Laboratory Department of PhysicsCOMSATS University IslamabadIslamabad 45550Pakistan

The investigation of Sm-Ce doping on structure,conduction,and dielectric response of Bi_(2)Ca_(2-2x)Sm_(x)CexCoO_(6)(x=0.000,0.025,0.050,0.075)(BCSCCO)are *** the specimens were synthesized by a facile synthesis technique named the co-precipitation route.X-ray diffraction(XRD)reveals that BCSCCO crystallizes into one phase with space group P21/*** crystallite size,dislocation density,lattice parameters,lattice strain,unit cell volume,and bulk density were determined using XRD *** structural properties of Bi_(2)Ca_(2)CoO_(6)were examined using calculations based on the density functional *** and experimental values discrepancy is less than 1%.A scanning electron microscope was used for performing a microstructural *** SEm images demonstrate the homogeneous distribution of grains with a range of sizes(0.054-0.090μm).The alternating current(ac)conductivity,dielectric permittivity,and tangent loss were also studied as a function of frequency(20 Hz-3 mHz)at different temperatures(100-500℃).All synthesized samples were examined using non-linear Debye's function to determine their spreading factor and relaxation *** specimen with the lowest crystallite size(∼23 nm)exhibits a high dielectric permittivity(∼3.80×10^(6)).The conduction mechanism was examined in the studied samples with the use of Jonscher's power *** power law indicates that the BCSCCO(x=0.000,0.025)follows correlated barrier hopping,whereas the x=0.050 and 0.075 compositions follow non-overlapping polaron *** studied specimen Bi_(2)Ca_(1.9)0Sm_(0.05)0Ce_(0.05)_(0)CoO_(6)with the highest density(∼5.65 g/cm^(3))displays a high electrical conductivity(∼46.1 S/cm).These findings correspond to those published for ceramics made from calcium cobaltite using solid-state reactions(5.0-26.0 S/cm).

关键词： Bismuth calcium samarium cerium cobaltite (BCSCCO) Spreading factor Conduction mechanism Rare earths

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The initial stages of Li_(2)O_(2) formation during oxygen reduction reaction in Li-O_(2) batteries:The significance of Li_(2)O_(2) in charge-transfer reactions within devices

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Journal of Energy Chemistry 2024年第1期88卷 223-231,I0006页

作者： Daniela m.Josepetti Bianca P.Sousa Simone A.J.Rodrigues Renato g.Freitas gustavo Doubek Advanced Energy Storage Division LABCenter for Innovation on New EnergiesSchool of Chemical EngineeringUniversity of CampinasAv Albert Einstein 50013083-852CampinasSPBrazil Institute of Physics&Department of Chemistry Laboratory of Computational MaterialsFederal University of Mato Grosso78060-900CuiabáMTBrazil

Lithium-oxygen batteries are a promising technology because they can greatly surpass the energy density of lithium-ion ***,this theoretical characteristic has not yet been converted into a real device with high *** with air contamination,metallic lithium reactivity,and complex discharge and charge reactions are the main issues for this technology.A fast and reversible oxygen reduction reaction(ORR)is crucial for good performance of secondary batteries',but the partial knowledge of its mechanisms,especially when devices are concerned,hinders further *** this perspective,the present work uses operando Raman experiments and electrochemical impedance spectroscopy(EIS)to assess the first stages of the discharge processes in porous carbon electrodes,following their changes cycle by cycle at initial operation.A growth kinetic formation of the discharge product signal(Li_(2)O_(2))was observed with operando Raman,indicating a first-order reaction and enabling an analysis by a microkinetic *** solution mechanism in the evaluated system was ascribed for an equivalent circuit with three time *** the time constant for the anode interface reveals to remain relatively constant after the first discharge,its surface seemed to be more *** model indicated that the reaction occurs at the Li_(2)O_(2) surface,decreasing the associated resistance during the initial discharge ***,the growth of Li_(2)O_(2) forms a hetero-phase between Li_(2)O_(2)/electrolyte,while creating a more compact and homogeneous on the Li_(2)O_(2)/cathode *** methodology here described thus offers a way of directly probing changes in surface chemistry evolution during cycling from a device through EIS analysis.

关键词： Li-O_(2)battery Operando Raman analysis Equivalent circuit modeling Time-constant distribution

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Achieving superior performance in powder-metallurgy near-βtitanium alloy by combining hot rolling and rapid heat treatment followed by aging

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Journal of materials Science & Technology 2024年第4期171卷 24-36页

作者： Fucheng Qiu Tuo Cheng Yuchao Song Orest m.Ivasishin Dmytro g.Savvakin guangyu ma Huiyan Xu College of materials Science and Engineering Jilin UniversityChangchun 130025China International Center of Future Science Jilin UniversityChangchun 130025China g.V.Kurdyumov Institute for metal Physics KyivUkraine College of Biological and Agricultural Jilin UniversityChangchun 130025China

Heat treatment plays an important role in tailoring the mechanical properties of powder-metallurgy(Pm)titanium ***,only limited work about the rapid heat treatment(RHT)of Pm titanium alloys has been *** this work,RHT was applied to Pm Ti-5Al-5mo-5V-1Cr-1Fe alloy after hot rolling to study the evolution of its mechanical properties and the influence of residual pores on its *** hot rolling and annealing,a fine and uniformα+βstructure with few residual pores is *** RHT,the primaryαdissolves gradually and completes in theβregion,and theβgrains then grow,resulting in the continuous decrease in elongation after ***,the tensile strength first increases and then decreases with increasing RHT temperature,owing to the increase in volume fraction of secondaryαinα+βregion and theβgrain growth inβ*** contrast to the RHT of cast-and-wrought titanium,the negative influence of residual pores lowers the RHT temperature for obtaining the highest tensile strength to a temperature below theβ-transus *** the negative influence of the residual pores,retained primaryαand fineβgrains with fine secondaryαinside contribute to achieving a good strength/ductility balance(1570 mPa and 6.1%,respectively).Addi-tionally,although at higher cycles to failure,the negative influence of residual pores increases as it affects the crack initiation zone at the subsurface,the good resistance of secondaryαto fatigue crack propaga-tion still enhances the fatigue strength considerably(about 300 mPa).This work suggests a cost-effective strategy to produce titanium alloys with high performance.

关键词： Rapid heat treatment Powder metallurgy mechanical properties Near-βtitanium Residual pores

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Braneworld black holes with modmax electrodynamics on the brane

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Communications in Theoretical Physics 2024年第6期76卷 120-128页

作者： Haryanto m Siahaan Jurusan Fisika Universitas Katolik ParahyanganJalan Ciumbuleuit 94Bandung 40141Indonesia

In this study,we investigate modmax electrodynamics localized within the Randall-Sundrum Ⅱ and Dvali-gabadadze-Porrati branes,deriving corresponding 3-brane spacetime solutions that conform to the effective Einstein equations in each specific *** construct solutions for charged black holes within the effective Einstein equation framework in both braneworld *** examination explores the trajectories of charged objects in this spacetime,underscoring the significance of the nonlinear *** analysis uncovers the fact that,similar to the prior modmax black hole investigation,the nonlinear parameter plays a pivotal role in suppressing the effective charge of the black hole,due to its definite positive value.

关键词： RS-II DgP modmax brane

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Higgs-like(pseudo)scalars in AdS_(4),marginal and irrelevant deformations in CFT_(3),and instantons on S^(3)

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Chinese Physics C 2024年第4期48卷 68-81页

作者： m.Naghdi Department of Physics Faculty of Basic SciencesUniversity of IlamIlamIran

Employing a 4-form ansatz of 11-dimensional supergravity over a non-dynamical AdS_(4)×S^(7)/Z_(k)background and setting the internal space as an S1 Hopf fibration on CP3,we obtain a consistent ***(pseudo)scalars,in the resulting scalar equations in Euclidean AdS_(4)space,may be considered to arise from(anti)m-branes wrapping around the internal directions in the(Wick-rotated)skew-whiffed m2-brane background(as the resulting theory is for anti-m2-branes),thus realizing the modes after swapping the three fundamental representations 8_(s),8_(c),and 8_(v) of SO(8).Taking the backreaction on the external and internal spaces,we obtain the massless and massive modes,corresponding to exactly marginal and marginally irrelevant deformations on the boundary CFT3,***,we obtain a closed solution for the bulk equation and compute its correction with respect to the background ***,considering the Higgs-like(breathing)mode m^(2)=18,having all supersymmetries as well as parity and scale-invariance broken,solving the associated bulk equation with mathematical methods,specifically the Adomian decomposition method,and analyzing the behavior near the boundary of the solutions,we realize the boundary duals in the SU(4)×U(1)-singlet sectors of the ABJm ***,introducing the new dual deformationΔ_(+)=3,6 operators made of bi-fundamental scalars,fermions,and U(1)gauge fields,we obtain the SO(4)-invariant solutions as small instantons on a three-sphere with the radius at infinity,which correspond to collapsing bulk bubbles leading to big-crunch singularities.

关键词： AdS_(4)/CFT_(3)correspondence scalar equations in AdS_(4) instantons marginal and irrelevant operators (anti)m-branes

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Influence of erbium on structural,and charged particles,photons,and neutrons shielding properties of Ba_(1-x)Er_(x)SnO_(3) perovskite ceramics

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Journal of Rare Earths 2024年第4期42卷 724-732页

作者： m.K.h.Hamad Nidal Dwaikat m.H.A.mhareb m.I.Sayyed R.m.Hamad Y.S.m.Alajerami m.A.Almessiere gameel Saleh Ahmad Hussein Alomari K.A.Ziq Department of Basic Sciences School of Social and Basics SciencesAl Hussein Technical UniversityKing Abdullah II St 242Amman11831Jordan Department of Physics College of Engineering and PhysicsInterdisciplinary Research Center for Advanced MaterialsKing Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Basic and Applied Scientific Research Center Imam Abdulrahman Bin Faisal UniversityP0.Box 1982Dammam31441Saudi Arabia Department of Physics Faculty of ScienceIsra UniversityAmman11622Jordan Department of Nuclear medicine Research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Arabia medical Imaging Department Applied Medical Sciences FacultyAl Azhar University-Gaza CityPo.Box 1277Palestine Department of Biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box1982Dammam 31441Saudi Arabia Department of Biomedical Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Energy&minerals Regulatory Commission Amman11821Jordan

Five perovskite ceramics samples of Ba_(1-x)Er_(x)SnO_(3) with x=0.00,0.05,0.10,0.15,and 0.20 were synthesized using the conventional solid-state reaction *** prepared samples were characterized by X-ray diffraction(XRD),Fourier transforms infrared(FTIR),and UV-Vis *** shielding properties against ionizing radiation were also *** XRD analysis shows the perovskite cubic structure as the major phase in all *** FTIR reveals a distinctive band around 614-620 cm^(-1) ascribed to the antisymmetric O-Sn-O ***-Vis spectroscopy was used to determine the bandgap according to diffuse reflectance,and the results display a fixed enhancement in the bandgap from 3.2 to 3.3 eV for all ***-ray shielding properties of the synthesized samples were experimentally measured and compared with XCOm computational *** relative differences(Δ,%)between experimental and theo retical values are low and fall within the 0.446%-7.10%*** addition of Er leads to the enhanced density,neutron,and gamma shielding *** contrast,charged particles’shielding parameters gradually reduce with rising Er *** results suggest that Ba_(1-x)Er_(x)SnO_(3) samples can be used in different radiation shielding applications.

关键词： Perovskite Ceramics gamma ray shielding mass stopping power Rare earths

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Carbon monoxide as C1 Building Block in Fine Chemical Synthesis

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Chinese Journal of Chemistry 2024年第2期42卷 199-221页

作者： Rui m.B.Carrilho mario J.F.Calvete gabor mikle Laszlo Kollar mariette m.Pereira University of Coimbra Coimbra Chemistry CentreDepartment of ChemistryRua Larga3004-535 CoimbraPortugal Department of general and Inorganic Chemistry and ELKH-PTE Research groupfor Selective Chemical Syntheses University of PecsIfjusag utja 6H-7624 PecsHungary

Carbon monoxide(CO)has become one of the most relevant and versatile renewable C1 building blocks for chemical synthesis,especially in the fine chemicals industry,due to the development of efficient and selective catalysts for its *** this review,we present a comprehensive critical analysis of the last 10 years literature on the use of CO as a renewable feedstock for fine chemicals *** review is organized by type of catalytic reaction,namely alkene and alkyne carbonylation,hydroformylation,carbonylation of aryl halides,carbonylative cross-coupling and C-H *** examples of the synthesis of relevant building blocks and/or known pharmaceuticals are *** is placed on examples of utilizing CO as the C1 building block in one or more catalytic *** catalyst used and the reaction conditions are consistently presented throughout all of the examples.

关键词： Carbon monoxide Fine chemicals Carbonylation Hydroformylation C-H functionalization

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Surface activation of viscose textiles via air,argon,and oxygen dielectric barrier discharge plasma:influence of peak voltage

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Plasma Science and Technology 2024年第7期26卷 134-147页

作者： Shrouk ELASHRY Usama m.RASHED mostafa A.WAHBA Hend m.AHmED Nabil m.ELSIRAgY Plasma Laboratory Physics DepartmentFaculty of scienceTanta UniversityTanta 31527Egypt Physics Department Faculty of Science(Male)Al-Azhar UniversityCairo 11651Egypt Textile Research Industrial Division National Research CentreDokkiGiza 12622Egypt

This paper discusses the use of atmospheric pressure dielectric barrier discharge(DBD)plasma treatment to enhance the surface qualities of viscose *** study explores the effects of different plasma gases,discharge voltages,and exposure times on the treated *** findings emphasize the importance of optimizing the plasma's peak voltage to achieve the desired surface treatment *** document also presents data on colour strength,wettability,colour fastness,and tensile strength of the treated fabrics,as well as scanning electron microscopy(SEm)analysis of surface morphology and chemical analysis using fouriertransition infrared spectroscopy(FTIR)and energy dispersive X-ray(EDX).The results show that treatment at a peak voltage of 11.83 k V is more efficient,except for the tensile strength which is enhanced at a peak voltage of 8.92 k *** oxygen plasma treatment significantly improves the colour strength,which exhibits an increase from 11 to *** intensified colour was attributed to the significant influence of electrostatic interactions between the charged hydroxyl groups of the oxygen plasma treated viscose textiles and the dye molecules,which enhance the *** oxygen DBD plasma exhibits a higher ability to enhance the properties of textiles when compared to air and argon *** study presents a sustainable,economical,secure,and ecologically friendly approach to explore new fabrics for specific uses.

关键词： Lissajous diagrams printability wettability tensile strength SEm EDX FTIR

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Classifying moisture sources associated with snowfall in the mountains of Lesotho

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Journal of mountain Science 2024年第6期21卷 1941-1953页

作者： Alexi m.mARINAKI Jennifer m.FITCHETT School of geography Archaeology and Environmental StudiesUniversity of the WitwatersrandPrivate Bag X3Wits 2050South Africa

An average of eight snowfall events occur each year in the eastern Lesotho *** snowfall events are typically associated with cut-off low(CoLs)systems and mid-latitude ***,the moisture sources of the snowfall are unclassified and *** Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)model,an air mass back trajectory model,has been used to evaluate moisture source waters locally in southern Africa and internationally in China and *** study uses HYSPLIT to determine the source moisture of snow in Lesotho.A list of all 82 snowfall events in Lesotho spanning 2017 to 2022 was compiled using the Snow Report SA Instagram page,including the date and location of snowfall.A 72-hour back trajectory for each snowfall event was initiated for both Afriski and the whole of *** amounts to models of moisture source trajectories for 28 and 82 snowfall days,*** air mass pathways are classified according to their frequency per snowfall event,per month in the snow season,per year and for the full *** this,associated moisture source regions and dominant air mass trajectories were *** study reports that the air mass trajectories associated with Afriski and Lesotho as a whole are very *** most common pathway of air mass trajectories transporting snow-bearing moisture to Lesotho was an inland trajectory from the northern regions of southern *** pathway makes up 16.6%of all trajectories reported and is associated with the Angola Low,the Congo Air Boundary and the *** High Pressure.

关键词： Eastern Lesotho Highlands Afriski Snow Cut-off Lows HYSPLIT Synoptic Climatology

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