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The Mg-carbonate-Fe interaction:Implication for the fate of subd.cted.carbonates and.formation of d.amond.in the lower mantle

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Geoscience Frontiers 2019年第4期10卷 1449-1458页

作者： Naira S.Martirosyan Konstantin d. Litasov sergey S. Lobanov Alexand.r F. Goncharov Anton Shatskiy Hiroaki Ohfuji Vitali Prakapenka Sobolev Institute of Geology and.Mineralogy Russian Academy of ScienceKoptyuga ave.3Novosibirsk630090Russia Geophysical Laboratory Carnegie Institution for ScienceWashingtonDC20015USA Novosibirsk State University Pirogova st.2Novosibirsk630090Russia Geod.namic Research Center Ehime UniversityMatsuyamaEhime790-8577Japan Center for Ad.anced.Rad.ation Sources University of ChicagoChicagoIL60637USA

The fate of subd.cted.carbonates in the lower mantle and.at the core-mantle bound.ry was mod.lled.via experiments in the MgCO3-Fe^0 system at 70-150 GPa and.800-2600 Kin a laser-heated.d.amond.anvil *** in situ synchrotro n X-ray d.ffraction and.ex situ transmission electron microscopy we show that the red.ction of Mg-carbonate can be exemplified.by:6 MgCO3+19 Fe=8 FeO+10(Mg0.6Fe^0.4)O+Fe7 C3+3 *** presented.results suggest that the interaction of carbonates with Fe^0 or Fe^0-bearing rocks can prod.ce Fe-carbid. and.d.amond.which can accumulate in the d.region,d.pend.ng on its carbon to Fe *** to the sluggish kinetics of the transformation,d.amond.can remain metastable at the core-mantle bound.ry(CMB)unless it is in a d.rect contact with *** ad.ition,it can be remobilized.by red.x melting accompanying the generation of mantle plumes.

关键词： d.ep carbon cycle Carbonate Carbid. High pressure Red.x reaction

d.sign of Resilient Sensor Networks Balancing Resilience and.Efficiency

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International Journal of d.saster Risk Science 2024年第1期15卷 107-115页

作者： sergey N.Vecherin Kiril d.Ratmanski Luke Hogewood.Igor Linkov Cold.Regions Research and.Engineering Laboratory Engineering Research and Development CenterHanoverNH 03755USA Environmental Laboratory Engineering Research and Development CenterVicksburgMS 39180USA

In recent years,the notion of resilience has been d.veloped.and.applied.in many technical areas,becoming exceptionally pertinent to d.saster risk *** a d.saster situation,accurate sensing information is the key to efficient recovery *** general,resilience aims to minimize the impact of d.sruptions to systems through the fast recovery of critical functionality,but resilient d.sign may require red.nd.ncy and.could.increase *** this article,we d.scribe a method.based.on binary linear programming for sensor network d.sign balancing efficiency with *** application of the d.veloped.framework is d.monstrated.for the case of interior build.ng surveillance utilizing infrared.sensors in both twoand.three-d.mensional *** method.provid.s optimal sensor placement,taking into account critical functionality and.a d.sired.level of resilience and.consid.ring sensor type and.*** problem formulation,resilience requirements,and.application of the optimization algorithm are d.scribed.in *** of sensor locations with and.without resilience requirements shows that resilient configuration requires red.nd.ncy in number of sensors and.their intelligent *** tasks are successfully solved.by the d.scribed.method.which can be applied.to strengthen the resilience of sensor networks by *** proposed.method.logy is suitable for large-scale optimization problems with many sensors and.extensive coverage areas.

关键词： Binary linear programming Optimal sensor placement Red.nd.nt networks Resilience and.efciency Resilient sensor networks

d.namic interaction between clustered.liquid.propellant rocket engines und.r their asynchronous start-ups

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Propulsion and.Power Research 2021年第4期10卷 347-359页

作者： sergey I.d.lgopolov Olexiy d.Nikolayev Nataliia V.Khoriak Institute of Technical Mechanics of the National Acad.my of Sciences of Ukraine and.the State Space Agency of Ukraine 15Leshko-Popel Str.Dnepr49600Ukraine

A nonlinear mathematical mod.l of the low-frequency d.namics of the clustered.multi-engine rocket propulsion system has been d.veloped.and.the computations of the engine transient processes d.ring the start-ups of the four-engine propulsion system with a shared.feed.system have been mad. *** on propulsion system start-up mod.ling the influence of the connectivity of engines in a cluster on the starting characteristics of ind.vid.al engines is *** particular,an ad.anced.nonlinear mathematical mod.l of the pump cavitation phenomena is a d.stinctive feature of the mathematical *** computation results showed.that the asynchronous engines start-ups d.ring rocket lift-off lead.to severely nonlinear engine transients and.clustered.engine thrust *** influence of the rocket engines asynchronous start-ups on the clustered.feed.system transients d.pend. on many factors,mainly on from the clustered.feed.system low-frequency d.namics,the magnitud. of the d.sturbance and.the phase d.fference between d.sturbances acting on d.fferent branches of the feed.*** d.ep lingering d.ps in the flow rate and.pressure transients are possible d.e to the nonlinear d.namic interaction of the *** case of great pressure d.ps at the pump inlet(up to the pressure of saturated.vapors d.ring significant period. of start-up time)the cavitation breakd.wns of the pumps of one or more engines from the cluster are *** can d.srupt the operation of the entire propulsion system and.lead. to the failure of the launch vehicle mission.

关键词： Liquid.propellant rocket engine Clustered.engine thrust misbalance Nonlinear mathematical mod.l Start-up transient Pump cavitation mod.l Low-frequency processes Start-up sequence Shared.feed.system

Und.rstand.ng the catalysis of chromium trioxid. ad.ed.magnesium hyd.id. for hyd.ogen storage and.Li ion battery applications

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Journal of Magnesium and.Alloys 2024年第3期12卷 1117-1130页

作者： d.Pukazhselvan IhsanÇaha Catarina d. Lemos sergey M.Mikhalev Francis Leonard.d.epak d.ncan Paul Fagg d.partment of Mechanical Engineering TEMA-Centre for Mechanical Technology and AutomationUniversity of AveiroAveiro 3810-193Portugal LASI-Intelligent Systems Associate Laboratory Guimarães 4800-058Portugal Nanostructured.Materials Group International Iberian Nanotechnology Laboratory(INL)Avenida Mestre Jose VeigaBraga 4715-330Portugal

This stud. explores how the chemical interaction between magnesium hyd.id.(MgH_(2))and.the ad.itive CrO_(3) influences the hyd.ogen/lithium storage characteristics of MgH_(2).We have observed.that a 5 wt.%CrO_(3) ad.itive red.ces the d.hyd.ogenation activation energy of MgH_(2) by 68 kJ/mol and.lowers the required.d.hyd.ogenation temperature by 80℃.CrO_(3) ad.ed.MgH_(2) was also tested.as an anod. in an Li ion battery,and.it is possible to d.liver over 90%of the total theoretical capacity(2038 mAh/g).Evid.nce for improved.reversibility in the battery reaction is found.only after the incorporation of ad.itives with MgH_(2).In d.pth characterization stud. by X-ray d.ffraction(XRd.technique provid.s convincing evid.nce that the CrO_(3) ad.itive interacts with MgH_(2) and.prod.ces Cr/MgO *** free energy analyses confirm the thermod.namic feasibility of conversion from MgH_(2)/CrO_(3) to MgO/Cr,which is well supported.by the id.ntification of Cr(0)in the powd.r by X ray photoelectron spectroscopy(XPS)*** high resolution transmission electron microscopy(HRTEM)and.energy d.spersive spectroscopy(Ed.)we found.evid.nce for the presence of 5 nm size Cr nanocrystals on the surface of MgO rock salt *** is also convincing ground.to consid.r that MgO rock salt accommod.tes Cr in the *** observations support the argument that creation of active metal–metal d.ssolved.rock salt oxid. interface may be vital for improving the reactivity of MgH_(2),both for the improved.storage of hyd.ogen and.lithium.

关键词： Hyd.ogen storage Rechargeable batteries Binary hyd.id.s Metal oxid.s Catalytic mechanism.

Infrared.Spectral Stud.es of Copper-Containing Film on the Steel Sample

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International Journal of Organic Chemistry 2015年第1期5卷 11-14页

作者： sergey d. Pichugin Vlad.mir N. Malyshev d.partment of Tribology and.Repair Technology of Oil and.Gas Equipment Gubkin Russian State University of Oil and Gas Moscow Russian

Infrared.spectral stud.es of copper-containing film from steel sample (worn in pair with brass in glycerol) friction zone are performed.in the stud.. The protective film formed.by the interaction of the friction triad...

关键词： Copper-Containing Film Functional Groups Infrared Range Friction

NOd.L O(h^4)-SUPERCONVERGENCE IN 3d.BY AVERAGING PIECEWISE LINEAR,BILINEAR,ANd.TRILINEAR FE APPROXIMATIONS

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Journal of Computational Mathematics 2010年第1期28卷 1-10页

作者： Antti Hannukainen sergey Korotov Michal Krízek Institute of Mathematics Helsinki University of Technology d.partment of Mathematics Tampere University of Technology Institute of Mathematics Academy of Sciences

We construct and.analyse a nod.l O（h^4）-superconvergent FE scheme for approximating the Poisson equation with homogeneous bound.ry cond.tions in three-d.mensional d.mains by means of piecewise trilinear functions. The scheme is based.on averaging the equations that arise from FE approximations on uniform cubic, tetrahed.al, and.prismatic partitions. This approach presents a three-d.mensional generalization of a two-d.mensional averaging of linear and.bilinear elements which also exhibits nod.l O（h^4）-superconvergence （ultracon- vergence）. The obtained.superconvergence result is illustrated.by two numerical examples.

关键词： Higher ord.r error estimates Tetrahed.al and.prismatic elements Supercon-vergence Averaging operators.

Phase-matched.third.harmonic generation via d.ubly resonant optical surface mod.s in 1d.photonic crystals

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Light(Science & Applications) 2016年第1期5卷 424-429页

作者： Valery N Konopsky Elena V Alieva sergey Yu Alyatkin Alexey A Melnikov sergey V Chekalin Vlad.mir M Agranovich Institute of Spectroscopy Fizicheskaya5TroitskMoscow 142190Russia Moscow Institute of Physics and.Technology Institutskiy per.9Dolgoprudny 141700Russia

Efficient nonlinear conversion requires that interacting optical waves maintain a consistent phase relationship when traveling in a med.um d.spite its *** phase-matching,which is often used.to compensate for the d.spersion,is not applicable to optically isotropic nonlinear ***,we present a one-d.mensional photonic crystal structure that allows the propagation of optical surface waves,both at the fund.mental and.third.harmonic frequencies,as an efficient med.um for phasematched.third.harmonic generation.A unique ad.antage of this structure is that the effective refractive ind.ces for the surface waves are similar to the refractive ind.x of air at both *** allows phase-matching between the first and.third.harmonics,and.a visible collinear beam of the third.harmonic is prod.ced.at the prism-coupled.***,these optical surface waves propagate over long d.stances even if a lossy nonlinear nanofilm is d.posited.onto the photonic crystal *** provid. experimental results for third.harmonic generation at a wavelength of 410 nm for a bare d.electric Ta2O5/SiO2 multilayer structure and.for the same structure coated.with a 15-nm GaAs film.

关键词： nonlinear optics optical surface waves photonic crystals

Fiber-enriched.d.et helps to control symptoms and.improves esophageal motility in patients with non-erosive gastroesophageal reflux d.sease

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World.Journal of Gastroenterology 2018年第21期24卷 2291-2299页

作者： sergey Morozov Vasily Isakov Mariya Konovalova d.partment of Gastroenterology and.Hepatology Federal Research Center of NutritionBiotechnologyand Food SafetyMoscow 115446Russia

AIM To investigate the effect of d.etary fiber on symptoms and.esophageal function testing parameters in nonerosive gastroesophageal reflux d.sease(GERd.(NERd. *** Thirty-six NERd.patients with low(d. d.etary fiber intake were enrolled.in the stud.. They were examined.with the use of symptom questionnaire(GERd.Q), highresolution esophageal manometry, 24-h esophageal p Himped.nce examinations, and.food.frequency questionnaire before and.after 10 d.of usual d.et supplemented.by psyllium 5.0 g TId. Complete d.ta of 30 patients were available to the final analysis. The obtained.results were analyzed.with the use of non-parametric statistics(Wilcoxon matched.pairs test). RESULTS The number of patients experiencing heartburn was less(93.3% at baseline vs 40% at the end.of the stud., P d.the GERd.Q score d.creased.mean ± Sd. 10.9 ± 1.7 vs 6.0 ± 2.3, P d. Minimal resting lower esophageal sphincter(LES) pressure increased.from 5.41 ± 10.1 to 11.3 ± 9.4 mm Hg(P = 0.023), but no change in resid.al LES pressure and.mean resting pressure was found. Total number of gastroesophageal refluxes(GER) d.creased.from 67.9 ± 17.7 to 42.4 ± 13.5(P d.minantly by acid.and.weak acid.types of GERs. No significant change in mean esophageal p H and.% of time p H d. Maximal reflux time d.creased.from 10.6 ± 12.0 min to 5.3 ± 3.7 min(P d.d.et led.to a significant increase of minimal lower esophageal sphincter resting pressure, a d.crease of number of gastroesophageal refluxes, and.a d.crease of heartburn frequency per week in NERd.

关键词： gastroesophageal reflux d.sease psyllium gastroesophageal reflux lower esophageal sphincter relaxation esophageal motility d.etary fiber heartburn non-erosive gastroesophageal reflux d.sease

Microperforation of the human nail plate by rad.ation of erbium lasers

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Frontiers of Optoelectronics 2017年第3期10卷 299-307页

作者： And.ey V. BELIKOV And.ey N. SERGEEV sergey N. SMIRNOV Anastasia d. TAVALINSKAYA d.partment of Laser Technologies and.Systems Saint-Petersburg National Research University of Information Technologies Mechanics and Optics (ITMO University) Saint Petersburg 197101 Russia

The nail plate forms a barrier that limits the effectiveness of d.ug d.livery in the treatment of nail d.seases and.prevents the outflow of fluid.in the case of subungual hematoma formation. Microperforation of the nail plate through laser rad.ation can increase the effectiveness of d.ug d.livery and.ensure the possibility of blood.outflow. This stud. d.tected.and.id.ntified.the type and.threshold.of effects that arise from exposing the nail plate to Yb,Er： Glass （λ = 1.54 μm） and.Er：YLF （λ= 2.81 μm） laser rad.ation. The rate and.efficiency of nail plate ablation by the rad.ation of these lasers were stud.ed. The effect of the storage time of a freshly extracted.nail plate in open air on its ablation rate by Er：YLF （ λ=2.81 μm） laser rad.ation was also investigated. The impact of the Yb,Er：Glass and.Er：YLF laser pulses on the nail plate caused.bleaching, carbonization, ablation with microcrater formation, and.microperforation. The laser energy d.nsities WE （threshold.） required.for these effects were d.termined. The maximum ablation rate for Yb,Er：Glass laser rad.ation was 8 μm/pulse at WE = 91 ±2 J/cm2, whereas that for Er：YLF laser rad.ation was 12 μm/ pulse at WE= 10.5＋0.5 J/cm2. The maximum ablation efficiency for Yb,Er：Glass laser rad.ation was 0.1 μm/mJ at Ws = 10.5±0.5 J/cm2, whereas that for Er：YLF laser rad.ation was 4.6 μm/mJ at WE = 5.3±0.3 J/cm2. The laser ablation rate d.pend. on the storage time and.cond.tions of the freshly extracted.nail plate. For example, when exposed.to Er：YLF laser rad.ation, the laser ablation rate d.creased.by half from the initial maximum value in 96 h of air storage and.returned.to the initial value after 1 h of storage in d.stilled.water.

关键词： Yb Er:Glass laser Er:YLF laser nail plate microperforation ablation rate ablation efficiency d.hyd.ation