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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

Deep bed filtration model for cake filtration and erosion

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 355-372页

作者： L.i.KUZMiNA Y.v.OSiPOv A.R.PESTEREv Department of Applied Mathematics HSE UniversityMoscow 101000Russia Department of computer Science and Applied Mathematics Moscow State University of Civil EngineeringMoscow 129337Russia

Many phenomena in nature and technology are associated with the filtration of suspensions and colloids in porous media. Two main types of particle deposition,namely, cake filtration at the inlet and deep bed filtration throughout the entire porous medium, are studied by different models. A unified approach for the transport and deposition of particles based on the deep bed filtration model is proposed. A variable suspension flow rate, proportional to the number of free pores at the inlet of the porous medium, is considered. To model cake filtration, this flow rate is introduced into the mass balance equation of deep bed filtration. For the cake filtration without deposit erosion,the suspension flow rate decreases to zero, and the suspension does not penetrate deep into the porous medium. in the case of the cake filtration with erosion, the suspension flow rate is nonzero, and the deposit is distributed throughout the entire porous medium. An exact solution is obtained for a constant filtration function. The method of characteristics is used to construct the asymptotics of the concentration front of suspended and retained particles for a filtration function in a general form. Explicit formulae are obtained for a linear filtration function. The properties of these solutions are studied in detail.

关键词： deep bed filtration cake filtration porous medium particle deposition and erosion analytical solution concentration front

Antibacterial HA-coatings on bioresorbable Mg alloy

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Journal of Magnesium and Alloys 2024年第5期12卷 1965-1985页

作者： K.v.Nadaraia D.v.Mashtalyar M.A.Piatkova A.i.Pleshkova i.M.imshinetskiy M.S.Gerasimenko E.A.Belov v.v.Kumeiko D.N.Kozyrev K.A.Fomenko v.v.Mostovaya B.R.Torpanov A.R.Biktimirov i.S.Osmushko S.L.Sinebryukhov S.v.Gnedenkov institute of chemistry FEB RAS 159 Pr.100-letiya VladivostokaVladivostok 690022Russia Far Eastern Federal University 10 Ajax BayRussky IslandVladivostok 690922Russia A.v.Zhirmunsky National Scientific center of Marine Biology FEB RAS 17 St.PalchevskogoVladivostok 690041Russia Regional clinical Dermatovenerological Dispensary 18 V St.GamarnikaVladivostok 690033Russia NMic“Treatment and Rehabilitation center” 3 Ivankovskoe highwayMoscow 125367Russia

in this study,a calcium-phosphate coating was formed on a Mg-Mn-ce alloy by the plasma electrolytic oxidation(PEO).The antibiotic vancomycin,widely used in the treatment of infections caused by Staphylococcus aureus(***),was impregnated into the *** with vancomycin showed high bactericidal activity against *** mechanical and electrochemical properties of the formed coatings were studied,as well as in vitro cytotoxicity tests and in vivo tests on mature male rats were *** to SEM,EDS,XRD and XPS data,coatings had a developed morphology and contained hydroxyapatite,which indicates high *** analysis of roughness of coatings without and with vancomycin did not reveal any differences,confirming the high roughness of the *** electrochemical tests,an increase in corrosion resistance by more than two times after the application of PEO coatings was *** to the results of an in vivo study,after 28 days of the implantation of samples with calcium phosphate PEO coating and vancomycin,no signs of inflammation were observed,while an inflammatory reaction developed in the area of implantation of bare alloy,followed by *** release tests from the coatings show a sharp decrease in the concentration of the released antibiotic on day 7 and then a gradual decrease until day *** the experiment,no significant deviations in the condition and behavior of the animals were observed;clinical tests did not reveal a systemic toxic reaction.

关键词： Bioactive coatings Biocompatibility Mg alloy Plasma electrolytic oxidation Hydroxyapatite vancomycin

Enhanced saturation magnetization in La^(3+) doped Nico ferrites prepared by sol-gel auto-combustion method

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Journal of Rare Earths 2024年第8期42卷 1546-1554,I0005页

作者： Maddileti Jelli vidyasagar Thopudurthy Krishna Reddy c.v. Department of Physics Rayalaseema UniversityKurnoolA.P518007.Iindia Department of Physics Govermment PolytechnicRayachotiA.P516269India

Lanthanum doped nickel-cobalt nano ferrites with chemical formula Ni_(0.5)co_(0.5)LaxFe_(2-x)O_(4)(x=0.05,0,10,0.15 and 0,20) were prepared using a simple sol-gel auto combustion *** basic structural properties were determined by X-ray diffraction method and the formation of single phased spinel ferrite was *** crystalline size decreased from 25 to 11 nm and lattice parameter a increases with increase of La *** surface morphology of these ferrites was observed by field-emission scanning electron microscopy(FESEM) and agglomerated irregular grains are observed with increase of the rare earth element La ***-dispersive X-ray spectroscopy(EDX) result confirms the presence of the required *** Fourier transform infrared spectroscopy(FTiR) spectrum indicates the formation of the spinel ferrite structure with M-O *** direct band measurements from ultraviolet-visible spectroscopy(Uv-vis) spectroscopy indicate that the direct band gap decreases from 1.39 to 1.19 ev for x=0.05 to x=0.15,then increases to 1.28 ev for x=*** room temperature magnetic properties of these ferrites were studied by a vibrating sample magnetometer(vSM).The enhanced saturation magnetization of 49.73 emu/g is observed for x=0.10 and then saturation magnetizations are gradually decreased for x=0.15 and x=*** the remanent magnetization and coercivity also follow the same trend.

关键词： Ferrites Sol-gel auto combustion La doping Magnetic properties Rare earths

Near resonance vibration isolation on a levered-dual response(LEDAR)coulomb-damped system by differential preloads/offsets in linear springs

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1033-1050页

作者： T.i.TOLUWALOJU c.K.THEiN D.HALiM Department of Mechanical Materials and Manufacturing EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100Zhejiang ProvinceChina Nottingham Ningbo china Beacons of Excellence Research and innovation institute University of Nottingham Ningbo ChinaNingbo 315048Zhejiang ProvinceChina

The levered-dual response(LEDAR)coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear *** takes the advantages of both the preloads/offsets in linear springs and the guiderail friction for realizing different levels of vibration *** isolation capacities are investigated on the strategies with both the horizontal and vertical guiderails,with the horizontal rail only,and without *** compressive preloads generally result in the consumption of most of the initial excitation energy so as to overcome the potential *** isolation onsets at the frequency ratio of 1∓0.095 on the left-hand side(LHS)and the right-hand side(RHS)of the lever are relative to the load plate *** observed near resonant isolation thus makes the LEDAR system a candidate for the isolation of the mechanical systems about resonance while opening a path for simultaneous harvesterisolation functions and passive functions at extreme frequencies.

关键词： lever ratio coulomb damping preload tension/compression isolation band/depth offset potential

Harnessing the power of complex light propagation in multimode fibers for spatially resolved sensing

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Photonics Research 2024年第3期12卷 411-422页

作者： DARcY L.SMiTH LiNH v.NGUYEN MOHAMMAD i.REJA ERiK P.ScHARTNER HEiKE EBENDORFF-HEiDEPRiEM DAviD J.OTTAWAY STEPHEN c.WARREN-SMiTH institute for Photonics and Advanced Sensing and School of Physics Chemistry and Earth SciencesThe University of AdelaideAdelaideSA 5005Australia Australian Research council centre of Excellence for Gravitational Wave Discovery(OzGrav) AdelaideSAAustralia Future industries institute University of South AustraliaMawson LakesSA 5095Australia Laser Physics and Photonics Devices Laboratory University of South AustraliaMawson LakesSA 5095Australia

The propagation of coherent light in multimode optical fibers results in a speckled output that is both complex and sensitive to environmental *** properties can be a powerful tool for sensing,as small perturbations lead to significant changes in the output of the ***,the mechanism to encode spatially resolved sensing information into the speckle pattern and the ability to extract this information are thus far *** this paper,we demonstrate that spatially dependent mode coupling is crucial to achieving spatially resolved *** leverage machine learning to quantitatively extract the spatially resolved sensing information from three fiber types with dramatically different characteristics and demonstrate that the fiber with the highest degree of spatially dependent mode coupling provides the greatest accuracy.

关键词： fiber spatially resolved

Measurement of yields and angular distributions ofγ-quanta from the interaction of 14.1 Mev neutrons with oxygen,phosphorus,and sulfur

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chinese Physics c 2024年第3期48卷 79-92页

作者： D.N.Grozdanov N.A.Fedorov S.B.Dabylova Yu.N.Kopatch i.N.Ruskov v.R.Skoy T.Yu.Tretyakova c.Hramco P.i.Kharlamov G.v.Pampushik P.G.Filonchik A.v.Andreev Joint institute for Nuclear Research(JiNR) DubnaRussia institute for Nuclear Research and Nuclear Energy Bulgarian Academy of SciencesSofiaBulgaria Faculty of Physics Lomonosov Moscow State UniversityMoscowRussia L.N.Gumilyov Eurasian National University AstanaKazakhstan Skobeltsyn institute of Nuclear Physics Moscow State UniversityMoscowRussia institute of chemistry of Moldova ChisinauRepublic of Moldova Moscow institute of Physics and Technology MoscowRussia

A study of the inelastic scattering of neutrons with an energy of 14.1 Mev on the nuclei of oxygen,phosphorus,and sulfur was performed at the TANGRA facility at JiNR(Dubna).The experiment aimed to refine existing data and obtain new data on the yields and angular distributions ofγ-quanta emitted by the studied nuclei due to neutron-induced nuclear reactions using the tagged neutron *** types of detector systems were used to registerγ-***γ-ray yields were measured using a high-purity germanium(HPGe)*** angular distributions ofγ-rays were obtained using a system of 18 scintillation detectors based on bismuth germanite Bi_(4)Ge_(3)O_(12)(BGO)located around the *** performed experiments measured the yields of two transitions for the reaction of tagged neutrons with 16O,nine transitions for the reaction with ^(31)P,and nine transitions for the reaction with ^(32)S for the first *** angular anisotropy of theγ-radiation accompanying the inelastic scattering of neutrons with an energy of 14.1 Mev on ^(31)P nuclei was also measured for the first time.

关键词： tagged neutron method yields of gamma-quanta high-resolution gamma-spectrometry neutron-nuclear reactions neutron scattering

Microstructure， electrochemical， wear and corrosive wear performance of laser-based powder bed fusion(lpbf) and wrought biomedical Ti-6Al-4v alloys

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Transactions of Nonferrous Metals Society of china 2024年

作者： A.G.Lekatou B.v.Efremenko v.Haoui v.G.Efremenko S.Emmanouilidou v.i.Zurnadzhy i.Petryshynets Yu.G.chabak i.i.Sili Laboratory of Applied Metallurgy Department of Materials Science and Engineering School of Engineering University of ioannina institute of Materials Science and computing University Research center of ioannina (URci) Pryazovskyi State Technical University Department of Physics institute of Materials Research of Slovak Academy of Sciences

Wrought and laser powder bed fusion （LPBF） Ti-6Al-4v specimens were comparatively evaluated， with the objective to determine LPBF Ti-6-4’s suitability for biomedical applications. Testing included nanoindentation， cyclic polarization in simulated body fluid （SBF， 37 ℃ ）， and dry and SBF “Ball-on-Plate” sliding. Wrought Ti-6-4 exhibited a lamellar （α+β） microstructure， whereas LPBF displayed a fine-grained α'-martensite microstructure. LPBF Ti-6-4 demonstrated ～3% higher indentation modulus and ～32% higher hardness， while wrought Ti-6-4 showed ～8% higher plasticity. Both alloys exhibited low corrosion rates (10–5mA/cm2order) and true passivity (10–4mA/cm2order). No localized corrosion was observed in either alloy， except for occasional metastable pitting in the LPBF alloy. However， LPBF Ti-6-4 presented higher corrosion rate and passive current， ascribed to its martensitic structure. During dry sliding， LPBF Ti-6-4 exhibited ～14% lower volume loss compared to wrought Ti-6-4. Sliding in SBF increased volume losses for both alloys， with wear resistances nearly equalized， as the advantage of LPBF Ti-6-4 decreased due to more intensive wear-accelerated corrosion induced by the stressed martensite. Overall， the results demonstrate the suitability of LPBF Ti-6Al-4v for biomedical uses.

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Old-growth mixed dipterocarp forests show variable losses and gains in aboveground biomass and standing carbon over forty years

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Forest Ecosystems 2024年第1期11卷 14-23页

作者： Sisira Ediriweera champika Bandara Tithira Lakkana Shanika Jayasinghe David Woodbury Arun Dayanandan B.M.P.Singhakumara Xiangcheng Mi i.A.U.N.Gunatilleke c.v.S.Gunatilleke Mark SAshton Department of Science and Technology Uva Wellassa UniversityBadullaSri Lanka The Forest School Yale School of the EnvironmentYale UniversityNew HavenCT06511USA Department of Forestry and Environmental Science University of Sri JayewardenepuraNugegodaSri Lanka State Key Laboratory of vegetation and Environmental change Institute of BotanyChinese Academy of SciencesBeijing100093China Botany Department University of PeradeniyaPeradeniyaSri Lanka

Background:No studies have documented long-term trends in aboveground biomass(AGB)for mixed-dipterocarp forests(MDF),the dominant rain forest type in tropical wet equatorial *** our study,we sought to document such trends over forty years across three sites representing lowland to lower montane ***:To do this,we established fifty 100 m×25 m plots in 1978 across three sites sampled along an elevation gradient,identified as mature old-growth *** measured trees for diameter at breast height that we identified to species and *** took wood samples to calculate species wood-specific *** re-measured plots in 1998 and again in ***:We show standing AGB for all sites combined to be 517.52 Mg·ha^(-1)in 1978,but this declined by 17%over 40 years to 430.11 Mg·ha^(-1).No differences exist among sites in AGB primarily because of considerable within site variation;but interactions of time with site show declines across sites were not uniform,one remained about the *** few species represented a high proportion of the AGB with the top five species comprising between 34%and 65%,depending upon site and year *** species,Mesua nagassarium,represented a disproportionately large amount of AGB and decline over time,particularly at the low elevation ***:Our results are directly relevant to estimating AGB and standing carbon sequestered in *** study is the first to demonstrate varying but overall,declining trends in amounts of AGB among forests making predictions of biomass and standing carbon in MDF difficult over wide regions.

关键词： Western ghats Shorea spp. Southeast Asia Sri Lanka Tropical rain forest Wood specific gravity

Photoluminescence,structural and antibacterial properties of co-doped β-ca3（PO4）2-type phosphates ca8cuRE（PO4）7（RE=Eu-Er）

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Journal of Rare Earths 2024年第9期42卷 1658-1668页

作者： ivan v.Nikiforov Ekaterina v.iliin Bogdan i.Lazoryak Sergey M.Aksenov Pavel v.Slukin Dina v.Deyneko Department of chemistry Lomonosov Moscow State University Laboratory of Arctic Mineralogy and Material Sciences Kola Science CentreRussian Academy of Sciences Geological institute Kola Science CentreRussian Academy of Sciences State Scientific center of Applied Microbiology and Biotechnology of Rospotrebnadzor 24

Novel ca8cuRE（PO4）7where RE3+=Eu3+,Tb3+,Dy3+,Ho3+and Er3+were synthesized by a solid-state method in *** structures of the samples were characterized by powder X-ray diffraction using Rietveld refinement to determine the occupation of crystal *** samples are found to have a centrosymmetric structure with space group R3c,as shown by dielectric *** synthesized ca8cuRE（PO4）7samples have multifunctional *** cu2+ions provide antibacterial properties,while the rare earth elements ions exhibit luminescence properties,and the β-ca3（PO4）2-type host is *** photoluminescence properties of RE3+ions were studied and compared with other simmilar ca8MRE（PO4）7phosphates,where M is a divalent *** photoluminescence intensity quenching in terms of energy transfer from RE3+to cu2+is *** bioactive properties were studied in relation to antibacterial activity against *** and *** syntesized ca8cuRE（PO4）7samples demonstrate very high and stable inhibition of bacteria *** correlation between crystal structure and properties is *** combining multiple approaches to the directio nal design of such materials,several important properties within a single chemical compound to achieve biovisualization and bioactive properties simultaneously can be combined.

关键词： Whitlockite-type structure Bioactive phosphates TcP Photoluminescence Rare earths