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Anode Plasma Electrolytic saturation of Titanium Alloys with Nitrogen and Oxygen

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Journal of Materials science & Technology 2016年第10期32卷 1027-1032页

作者： P.N.Belkin s.A.Kusmanov A.v.Zhirov v.s.Belkin v.I.Parfenyuk Nekrasov Kostroma state University 1 May14Kostroma 156961Russia

In this work, we investigated the features of the anode plasma electrolytic saturation of titanium alloys with nitrogen and oxygen. In this case, the titanium samples may be heated to 1050 ℃ using aqueous solutions of ammonium chloride as working electrolyte. The weight of titanium samples is found to change due to their oxidation and anode dissolution. An X-ray diffractometer, a scanning electron microscope,nuclear proton backscattering and an optical microscope were used to characterize the phase and elemental composition of the modified layer. The electrolyte composition（10 wt% ammonium chloride, 5wt% ammonia） and processing mode（850 ℃, 5 min） of commercially pure titanium（CP-Ti） allowing to obtain the hardened surface layer up to 0.1 mm with microhardness of 220 Hv were proposed. surface roughness Ra of samples after their nitriding for 5 min at 800 ℃ decreases from 1.67 to 0.082 μm. The anode plasma electrolytic nitriding could decrease friction coefficient and increase wear resistance of the CP-Ti. It is found that the anodic nitriding of low alloy titanium alloys reduces their corrosion rate in an aqueous solution of sulphuric（4.5%） and salt（0.2%） acids by 2 orders of magnitude. Results of cyclic testing show that anodic nitriding of commercial titanium leads to a decrease in corrosion rate by 8 times in solution of hydrochloric acid（6%） with addition of protein and vitamin.

关键词： Plasma electrolysis Titanium Nitriding Wear Corrosion

Carboxylates as green corrosion inhibitors of magnesium alloy for biomedical application

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Journal of Magnesium and Alloys 2024年第7期12卷 2909-2936页

作者： A.s.Gnedenkov s.L.sinebryukhov A.D.Nomerovskii v.s.Marchenko A.Yu.Ustinov s.v.Gnedenkov Institute of Chemistry of FEB RAs 159 Pr.100-letiya VladivostokaVladivostok 690022Russia

The efficiency of the green inhibitors(sodium salts of fumarate,glycolate and gluconate)in suppressing corrosion of the structural MA8 magnesium alloy(Mg–Mn–Ce)and the biomedical Mg–0.8Ca alloy was studied using the hydrogen evolution measurements,mass loss test,EIs,PDP,svET/*** analysis of the morphology,chemical composition,and growth kinetic of corrosion films formed in 0.9 wt%NaCl solution with and without corrosion inhibitors was carried *** most compact surface film with the smallest thickness was formed in a saline solution with sodium *** Mg alloy samples exhibited the highest polarization resistance,the lowest localized electrochemical activity,and the lowest corrosion rate in saline with the addition of sodium fumarate and sodium *** efficiency of the applied inhibitors was up to 81%.The model of the corrosion mechanism based on the sorption of molecules of organic inhibitors is *** results show the high compatibility of the used inhibitors with the calcium-phosphate PEO-matrix,indicating the possibility of forming a self-healing coating by means of these active substances.

关键词： Magnesium and its alloys Organic inhibitor Electrochemical behavior PEO-coatin Bioresorbable implant Degradation mechanism

Conformally symmetric wormhole solutions supported by non-commutative geometry in f(Q,T)gravity

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Communications in Theoretical Physics 2024年第2期76卷 111-124页

作者： Chaitra Chooda Chalavadi v venkatesha N s Kavya s v Divya Rashmi Department of P.G.studies and Research in Mathematics Kuvempu UniversityShankaraghattaShivamogga 577451KarnatakaIndia Department of Mathematics Vidyavardhaka College of EngineeringMysuru—570002India

This paper investigates wormhole solutions within the framework of extended symmetric teleparallel gravity,incorporating non-commutative geometry,and conformal *** achieve this,we examine the linear wormhole model with anisotropic fluid under Gaussian and Lorentzian *** primary objective is to derive wormhole solutions while considering the influence of the shape function on model parameters under Gaussian and Lorentzian *** resulting shape function satisfies all the necessary conditions for a traversable ***,we analyze the characteristics of the energy conditions and provide a detailed graphical discussion of the matter contents via energy ***,we explore the effect of anisotropy under Gaussian and Lorentzian ***,we present our conclusions based on the obtained results.

关键词： traversable wormhole f(Q T)gravity energy conditions non-commutative geometry conformal motion

vagus nerve stimulation in intracerebral hemorrhage:the need for further research

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Neural Regeneration Research 2025年第11期20卷 3213-3214页

作者： sheharyar s.Baig Ali N.Ali Arshad Majid sheffield Institute for Translational Neuroscience Division of NeuroscienceThe University of SheffieldSheffieldUK

vagus nerve stimulation(vNs)and stroke:stroke is the second leading cause of death and the third leading cause of disability worldwide(Baig et al.,2023).There have been significant paradigm shifts in the management of acute ischemic stroke through mechanical *** chronic ischemic stroke,invasive vNs paired with rehabilitation is associated with a significant increase in upper limb motor recovery and is FDA-approved(Baig et al.,2023).There are no treatments of similar efficacy in acute intracerebral hemorrhage(ICH)where several promising trials,e.g.,TICH-2,sTOP-AUsT,and TRAIGE did not show improvements in functional outcomes(Puy et al.,2023).

关键词： stimulation acute

Isomeric ratio of the ^(181)Ta(γ,3n)^(178m,g)Ta reaction products at energy Eγmax up to 95 Mev

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Chinese Physics C 2022年第1期46卷 102-109页

作者： O.s.Deiev I.s.Timchenko s.N.Olejnik v.A.Kushnir v.v.Mytrochenko s.A.Perezhogin National science Center"Kharkiv Institute of Physics and Technology" 1 Akademicheskaya St.61108 KharkivUkraine

The photoneutron reaction^(18)Ta(y,3m)(178m,g)Ta was investigated with the beam from the NsC KIPT electron linear accelerator *** measurements were performed using the residual y-activity *** bremsstrahlung flux-averaged cross sections((E_(γmax))>.(r(E_(γmax))>m.somerie ratio of the re-action products d(E_(γmax))were *** theoretical values of the averaged cross-sections and isomeric ratio were calculated using the partial cross-sections from the TALYs1.95 code for different level density models LD 1-6..The obtained experimental d(E_(γmax))agree with the data in the lterature,but differ from the theoretical values in ab-solute magnitude and the behavior of the energy dependence.A comparison of the determined averaged cross-sec-tions with the calculated cross sections showed the best agreement for the case of the LD 5 model.

关键词： bremsstrahlung flux-averaged cross-section isomeric ratio bremsstrahlung end-point energy of 35-95 Mev activation and off-line 7-ray spectrometric technique TALYs1.95 GEANT4.9.2

Cross-sections for the 27Al(γ,x)22Na multichannel reaction with the 28.3 Mev difference of reaction thresholds

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Chinese Physics C 2022年第6期46卷 129-137页

作者： O.s.Deiev I.s.Timchenko s.N.Olejnik v.A.Kushnir v.v.Mytrochenko s.A.Perezhogin National science Center"Kharkov Institute of Physics and Technology" 1 Akademichna St.61108 KharkivUkraine

The bremsstrahlung flux-averaged cross-sections(σ(Eγmax))and the cross-sections per equivalent photon(σ(Eγmax)Q)were first measured for the photonuclear multichannel reaction ^(27)Al(γ,x)22 Na at end-point bremsstrahlung gamma energies ranging from 35 Mev to 95 *** experiments were performed with the beam from the NsC KIPT electron linear accelerator LUE-40 using theγ-activation *** bremsstrahlung quantum flux was calculated with the GEANT4.9.2 program and was also monitored via the ^(100)Mo(γ,n)^(99)Mo *** flux-averaged cross-sections were calculated using the partial cross-sectionσ(E)values computed with the TALYs1.95 code for different level density *** is given to special features of calculating the cross-sectionsandfor the case of the final nucleus ^(22)Na via several partial channels x:nα+dt+npt+2 n^(3) He+n2d+2 npd+2 p3 n.

关键词： bremsstrahlung flux-averaged cross-section bremsstrahlung end-point energy of 35-95 Mev activation and off-lineγ-ray spectrometric technique TALYs1.95 GEANT4.9.2

Disproportionation of ethylbenzene in the presence of C_8 aromatics

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Journal of Natural Gas Chemistry 2009年第3期18卷 369-374页

作者： N.sharnappa s.Pai v.v.Bokade Catalysis Division National Chemical Laboratory

The selective synthesis of p-diethylbenzene （p-DEB） by disproportionation of ethylbenzene （EB） in the presence of aromatics like m- and p- xylene isomers has been studied over a pore size regulated HZsM-5 catalyst. The industrial feed having different compositions of ethylbenzene and xylene isomers was used for the experimentation. Hence, they were expected to hinder the movement of reactant molecules both on the external surface and within the zeolite channels. It was observed that irrespective of the different feed compositions the concentration of the xylene isomers was intact in the product. There is no other byproducts formation like para-ethylmethyl benzene. The effects of varying the concentration of aromatic compounds in the feed on ethylbenzene conversion and product distribution over the parent and modified H-ZsM-5 catalyst have been discussed. Ethylbenzene disproportionation reaction follows the pseudo first order reaction with an activation energy of 8.6 kcal/mol.

关键词： ethylbenzene xylene isomers catalyst disproportionation diethylbenzene

Influence of ZrO_(2)/siO_(2) nanomaterial incorporation on the properties of PEO layers on Mg-Mn-Ce alloy

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Journal of Magnesium and Alloys 2022年第2期10卷 552-566页

作者： D.v.Mashtalyar I.M.Imshinetskiy K.v.Nadaraia A.s.Gnedenkov s.L.sinebryukhov A.Yu.Ustinov A.v.samokhin s.v.Gnedenkov Institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok 690022Russian Federation Far Eastern Federal University Vladivostok 690922Russian Federation A.A.Baikov Institute of Metallurgy and Materials science Russian Academy of SciencesMoscow 119991Russian Federation

The properties of coatings formed on the MA8 magnesium alloy by the plasma electrolytic oxidation in electrolytes containing mechanical mixture of zirconia and silica nanoparticles in concentrations of 2,4 and 6 g/l have been *** has been established by sEM,EDs,and XPs that ZrO_(2)/siO_(2)nanoparticles successfully were incorporated into the ***-Raman spectroscopy showed the presence of ZrO_(2)in tetragonal and monoclinic forms in the PEO-coating composition as well as Mg_(2)siO_(4) in tetrahedral configuration uniformly distributed in the outer part of *** coatings significantly reduce corrosion current density in comparison with bare Mg alloy and base PEOlayer(from 2.4×10^(–7)A/cm^(2) for base PEO layer to 0.7×10^(–7)A/cm^(2) for coatings with nanoparticles).It has been found that the presence of solid nanoparticles in the composition of coating has a positive effect on their hardness(this parameter was increased from 2.1±0.3 GPa to 3.1±0.4 GPa)and wearproof(the wear was reduced from(4.3±0.4)×10^(–5)mm^(3)/(N×m)to(3.5±0.2)×10^(–5)mm^(3)/(N×m)).

关键词： Plasma electrolytic oxidation Composite coatings Nanoparticles Zirconia silica Protective coatings

Magnetic nanoparticles and concentrated magnetic nanofluids:synthesis,properties and some applications

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China Particuology 2007年第1期5卷 43-49页

作者： Ladislau vks Doina Bica Mikhail v. Avdeev Lab Magnetic Fluids CFATR Romanian Academy-Timisoara Division Timisoara Romania National Center for Engineering of Systems with Complex Fluids Univ. Politehnica Timisoara Timisoara Romania Lab Magnetic Fluids CFATR Romanian Academy-Timisoara Division Timisoara Romania Frank Laboratory of Neutron Physics Joint Institute for Nuclear Research Dubna Russia

This paper reviews some recent results concerning chemical synthesis of magnetic nanoparticles and preparation of various types of magnetic nanofluids. structural properties and behaviour in external magnetic field of magnetic nanofluids will be emphasized with relation to their use in leakage-free rotating seals and in biomedical applications.

关键词： Magnetic nanoparticle Magnetic nanofluid Rotating seal Biomedical application Chemical co-precipitation structural characterization