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Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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journal of Rare Earths 2024年第1期42卷 66-75页

作者： s.W.Wi Y.s.Lee department of Physics and Integrative Institute of Basic sciences Soongsil University

We investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence sensitizer Rare earths

Fuzzy difference Equations in diagnoses of Glaucoma from Retinal Images Using deep Learning

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Computer Modeling in Engineering & sciences 2024年第4期139卷 801-816页

作者： d.dorathy Prema Kavitha L.Francis Raj sandeep Kautish Abdulaziz s.Almazyad Karam M.sallam Ali Wagdy Mohamed department of Mathematics Voorhees CollegeVelloreTamil NaduIndia Chandigarh Group of Colleges JhanjeriMohaliPunjabIndia department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityP.O.Box 51178Riyadh11543Saudi Arabia Faculty of science and Technology School of IT and SystemsUniversity of CanberraCanberraAustralia Operations Research department Faculty of Graduate Studies for Statistical ResearchCairo UniversityGiza12613Egypt Applied science Research Center Applied Science Private UniversityAmman11937Jordan

The intuitive fuzzy set has found important application in decision-making and machine *** enrich and utilize the intuitive fuzzy set,this study designed and developed a deep neural network-based glaucoma eye detection using fuzzy difference equations in the domain where the retinal images *** image detections are categorized as normal eye recognition,suspected glaucomatous eye recognition,and glaucomatous eye *** degrees associated with weighted values are calculated to determine the level of concentration between the fuzzy partition and the retinal *** proposed model was used to diagnose glaucoma using retinal images and involved utilizing the Convolutional Neural Network(CNN)and deep learning to identify the fuzzy weighted regularization between *** methodology was used to clarify the input images and make them adequate for the process of glaucoma *** objective of this study was to propose a novel approach to the early diagnosis of glaucoma using the Fuzzy Expert system(FEs)and Fuzzy differential equation(FdE).The intensities of the different regions in the images and their respective peak levels were *** the peak regions were identified,the recurrence relationships among those peaks were then *** partitioning was done due to varying degrees of similar and dissimilar concentrations in the *** and dissimilar concentration levels and spatial frequency generated a threshold image from the combined fuzzy matrix and *** distinguished between a normal and abnormal eye condition,thus detecting patients with glaucomatous eyes.

关键词： Convolutional Neural Network(CNN) glaucomatous eyes fuzzy difference equation intuitive fuzzy sets image segmentation retinal images

Effect of Ta_(2)O_(5)nanoparticles on bioactivity,composition,structure,in vitro and in vivo behavior of PEO coatings on Mg-alloy

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journal of Magnesium and Alloys 2024年第6期12卷 2360-2379页

作者： d.V.Mashtalyar I.M.Imshinetskiy V.V.Kashepa K.V.Nadaraia M.A.Piatkova A.I.Pleshkova K.A.Fomenko A.Yu.Ustinov s.L.sinebryukhov s.V.Gnedenkov Institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok690022Russia Far Eastern Federal University Vladivostok690950Russia Regional Clinical dermatovenerological dispensary Vladivostok690033Russia

The present study investigates the physical and chemical characteristics,behavior in vitro and in vivo,and biocompatibility of coatings containing Ta_(2)O_(5),which are obtained by plasma electrolytic oxidation(PEO)on MA8 magnesium *** obtained coatings demonstrate in vivo biocompatibility and in vitro *** to the base PEO coating,the layers containing Ta_(2)O_(5)facilitate the development of apatite in simulated body fluid,suggesting that the inclusion of nanoparticles improves bioactivity of the *** was found that incorporation of Ta_(2)O_(5)nanoparticles increases roughness and porosity of the formed layers by increasing particle concentration in electrolytes for the PEO process contributing to sufficient soft tissue ingrowth in *** on in vivo studies,these coatings also provide favorable tissue response and minimal inflammatory reaction in comparison with the bare magnesium alloy due to protection of living tissues from deleterious corrosion events of magnesium implant such as local alkalization and intense hydrogen *** results obtained in the present study concluded biocompatibility,tissue integration of the PEO coatings containing Ta_(2)O_(5)nanoparticles making them a promising protective layer for biodegradable magnesium implants.

关键词： Plasma electrolytic oxidation Bioactive coatings Tantalum pentoxide simulated body fluid(sBF) Apatite formation Histology

First evidence for chiral wobbling of triaxial nuclei

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Nuclear science and Techniques 2024年第7期35卷 4-7页

作者： s.Frauendorf department of Physics and Astronomy University of Notre DameNotre DameIN 46556USA

Chirality(Greek“handiness”)is a property of many com-plex *** molecules exist in two forms,one being the mirror image of the *** for our hands,it is impossible to make the images identical by a suitable *** two forms are called left-handed and *** have the same binding energy,because the electro-magnetic interaction,which holds the molecule together,does not change under a *** properties that are insensitive to the geometry are also the *** different geometry is the reason why the left-handed form turns the polarization plane of transmitted light in one direction by some angle while the right-handed form turns it in the oppo-site direction by the same ***,the geometrical differences between the two species may have other *** two species of the carvon molecule shown in Fig.1 taste quite differently.

关键词： turns Chiral mirror

Tribological behavior of lubricant-impregnated porous polyimide

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Friction 2024年第4期12卷 711-725页

作者： jinbang LI Ningning ZHOU janet s.s.WONG school of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211China Beijing Key Laboratory of Long-life Technology of Precise Rotation and Transmission Mechanisms Beijing Institute of Control EngineeringBeijing 100029China department of Mechanical Engineering Imperial College LondonLondon SW72AZUK

Porous materials impregnated with lubricants can be used in conditions where limited lubricant is *** this work,three porous polyimides(PPI)with different densities were ***(PAO)impregnated PPI(iPPI)discs were rubbed against steel and sapphire *** operando observations of the iPPI-sapphire contacts show that oil is released under an applied load,forming a meniscus around *** at the outlet is created at high sliding *** amount of released oil increases with increasing PPI *** moduli,E*,estimated based on the actual contact size show that trapped oil in iPPIs contributes to load *** higher speeds,tribological rehydration of the contact occurs in low density iPPI,with that E*rises with *** high density PPIs,high speeds give a constantly high E*which is limited by the viscoelastic properties of the PPI network and possibly the rate of oil *** of iPPI-steel contacts is governed by the mechanical properties of the PPI,the flow of the lubricant,and the roughness of the PPI *** low-and medium-density(highly porous,high roughness)PPIs,large amount of oil is released,and lubrication is mainly via lubricant restricted in the contact in the pores and possibly tribological *** high density(low porosity)PPI,with lower roughness,hydrodynamic lubrication is achieved which gives the lowest *** results show that polymeric porous materials for effective lubrication require the optimization of its surface roughness,stiffness,oil flow,and oil retentions.

关键词： polyimide porous material friction mechanism polymer limited lubrication

Influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 563-580页

作者： N.HUMNEKAR d.sRINIVAsACHARYA department of Mathematics National Institute of TechnologyWarangal 506004TelanganaIndia

The influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel is *** darcyBrinkman model is used to characterize the fluid flow dynamics in porous *** analytical solutions are obtained for the unidirectional and completely developed *** on a normal mode analysis,the generalized eigenvalue problem under a perturbed state is *** eigenvalue problem is then solved by the spectral ***,the critical Rayleigh number with the corresponding wavenumber is evaluated at the assigned values of the other flow-governing *** results show that increasing the darcy number,the Lewis number,the dufour parameter,or the soret parameter increases the stability of the system,whereas increasing the inclination angle of the channel destabilizes the ***,the flow is the most unstable when the channel is vertically oriented.

关键词： nanofluid inclined channel variable viscosity linear stability double dif-fusion porous medium

Weight regain after intragastric balloon for pre-surgical weight loss

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World journal of Gastrointestinal surgery 2024年第7期16卷 2040-2046页

作者： danielle Abbitt Kevin Choy Alexandra Kovar Teresa s jones Krzysztof j Wikiel Edward L jones department of surgery University of ColoradoAuroraCO 80045United States department of surgery Rocky Mountain Regional Veteran Affairs Medical CenterAuroraCO 80045United States

BACKGROUNd Over one-third of Americans carry the diagnosis of obesity,many also with obesity-related *** can place patients at increased risk of operative and postoperative *** intragastric balloon has been shown to aid in minor weight loss,however its weight recidivism in patients requiring short interval weight loss has not been well *** To evaluate weight loss,ability to undergo successful elective surgery after intragastric balloon placement,and weight management after balloon *** This study is a retrospective review of patients in a single academic institution undergoing intragastric balloon placement from 2019-2023 to aid in weight loss prior to undergoing elective *** outcomes including weight loss,duration of balloon placement,successful elective surgery,weight regain postballoon and post-procedure complications were *** criteria included those with balloon in place at time of *** Thirty-three patients completed intragastric balloon therapy from 2019-2023 as a bridge to elective *** patients were required to participate in a 12-month weight management program to be eligible for balloon *** surgeries included incisional hernia repair,umbilical hernia repair,inguinal hernia repair,and knee and hip *** average age at placement was 53 years±11 years,majority(91%)were *** average duration of intragastric balloon therapy was 186 days±41 *** average weight loss was 14.0 kg±7.4 kg and with an average percent excess body weight loss of 30.0%(7.9%-73.6%).Over half of the patients(52.0%)achieved the goal of 30-50 lbs(14-22 kg)weight ***-one patients(64%)underwent their intended elective surgery,2 patients(6%)deferred surgery due to symptom relief with weight loss ***-one of the patients(64%)have documented weights in 3 months after balloon removal,in these patients the majority(76%)gained weight after balloon *** pat

关键词： Intragastric balloon Weight loss Obesity Bariatric Body mass index

A detailed comparison of the composition of(RE)-Ba-Cu-O-Ag bulk superconductors

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superconductivity 2024年第1期9卷 87-94页

作者： j.V.j.Congreve Y.shi A.R.dennis H.druiff N.C.Tutt d.A.Cardwell j.H.durrell department of Engineering University of CambridgeCambridgeUK

The homogeneity of the microstructure and composition are critical in determining the properties of rare earthbarium‐cuprate,single grain bulk superconductors[(RE)BCO].The magnitude of the trapped magnetic field achieveable in these technologically important materials,in particular,is influenced heavily by the size and distribution of(RE)_(2)BaCuO_(x)(RE‐211)flux pinning inclusions in the bulk microstructure,whereas the size and distribution of silver agglomerates present within the bulk superconducting matrix correlate directly with improved mechanical *** careful engineering,these materials have significant potential for application in range of devices related to energy storage,medicine,electro‐magnetic machinery and microelectronic *** of(RE)BCO bulk superconductors typically involves heating a powder compact above its peritectic decomposition temperature followed by slow cooling to facilitate the growth of a single ***(RE)BCO composition has a different peritectic temperature and growth rate,which,therefore,necessitates different requirements in the heating *** fabrication temperature and growth rate,for example,may have an effect on the RE‐211 and silver distribution,which may,in turn,affect the superconducting properties of the resulting single *** this work we compare the distributions of silver and RE‐211 in the single grain microstructures of YBCOAg,GdBCO‐Ag,EuBCO‐Ag and smBCO‐Ag bulk superconductors using optical microscopy,scanning electron microscopy and energy dispersive X‐ray *** observe that the distributions are very similar along both the a/b‐axis and c‐axis of these *** suggests that factors other than the maximum temperature used to achieve peritectic decomposition and the rate of single grain growth are particularly influential in determining the properties of the as‐processed samples in the top seeded melt growth *** observation demonstrates there is freedom to us

关键词： YBCO‐Ag GdBCO‐Ag smBCO‐Ag EuBCO‐Ag Composition Bulk superconductor

Highly defective dark TiO_(2) Modified with Pt: Effects of Precursor Nature and Preparation Method on Photocatalytic Properties

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Transactions of Tianjin University 2024年第2期30卷 198-209页

作者： E.d.Fakhrutdinova O.A.Reutova T.A.Bugrova I.Yu.Ovsyuk L.s.Kibis O.A.stonkus d.B.Vasilchenko O.V.Vodyankina V.A.svetlychnyi National Research Tomsk state University TomskRussia 634050 Novosibirsk state University NovosibirskRussia 630090 Boreskov Institute of Catalysis NovosibirskRussia 630090 Nikolaev Institute of Inorganic Chemistry NovosibirskRussia 630090

The study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibited similar phase compositions, specific surface areas, and Pt contents. High-resolution transmission electron microscopy coupled with pulsed CO adsorption revealed increased dispersity when photoreduction and the hydroxonitrate complex (Me _(4) N) _(2) [Pt _(2) (OH) _(2) (NO _(3) ) _(8) ] were used. The sample featured a high content of single-atom species and subnano-sized Pt clusters. The X-ray photoelectron spectroscopy results showed that the photoreduction method facilitated the appearance of a larger number of Pt ^(2+) states, which appeared owing to the strong metal-support interaction (sMsI) eff ect of the transfer of electron density from the electron-saturated defects on the TiO _(2) surface to Pt ^(4+) . In the hydrogen evolution reaction, samples with a significant fraction of the Pt ^(2+) ionic component, capable of generating short-lived Pt^(0) single-atom sites under irradiation due to the sMsI eff ect, exhibited the highest photocatalytic activity. The 0.5Pt(C)/TiO_(2) -Ph sample exhibited the highest hydrogen yield with a quantum efficiency of 0.53, retaining its activity even after 8 h of operation.

关键词： dark(black)TiO_(2) Pulsed laser ablation Platinum reduction method Precursor type Photocatalysis Hydrogen evolution reaction