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Characterization and Electrochemical Properties of Nanostructured Zr-Doped Anatase TiO_2 Tubes Synthesized by Sol–Gel Template Route

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Journal of Materials Science & Technology 2017年第6期33卷 527-534页

作者： Denis P.Opra Sergey v.Gnedenkov Sergey L.Sinebryukhov Elena I.voit Alexander A.Sokolov Evgeny B.Modin Anatoly B.Podgorbunsky Yury v.Sushkov veniamin v.Zheleznov Institute of Chemistry Far Eastern Branch of Russian Academy of Sciences Far Eastern Federal University National Research Centre "Kurchatov Institute"

A series of nanostructured Zr-doped anatase TiO_2 tubes with the Zr/Ti molar ratio of 0.01, 0.02, 0.03, and0.09 were prepared by a sol–gel technology on a carbon fiber template. The electrochemical performance of Zr-doped anatase TiO_2 as anodes for rechargeable lithium batteries was investigated and compared with undoped titania. Tests represented that after 35-fold charge/discharge cycling at C/10 the reversible capacity of Zr-doped titania（Zr/Ti = 0.03） reaches 135 m A h g^（-1）, while the capacity of undoped titania（Zr/Ti = 0） yielded only 50 m A h g^（-1）. Based on the results of the physicochemical investigation, three reasons of improving electrochemical performance of Zr-doped titania were suggested. According to the scanning electron microscopy and transmission electron microscopy, Zr^（4＋） doping induces a decrease in nanoparticle size, which facilitates the Li＋diffusion. The Raman investigations show the more open structure of Zr-doped TiO_2 as compared to undoped titania due to changing of the unit cell parameters, that significantly affects on the reversibility of the insertion/extraction process. The electrochemical impedance spectroscopy results indicate that substitution of Zr^（4＋） for Ti^（4＋） into anatase TiO_2 has favorable effects on the conductivity.

关键词： Li-ion batteries Anatase titania Nanostructured materials Sol–gel template process Doping Electrochemical performance

New-type internal target for structural ion stripping

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Chinese Physics C 2018年第1期42卷 151-156页

作者： D.N.Makarov v.I.Matveev Federal Center for Integrated Arctic Research Russian Academy of Sciences Arkhangelsk 163000 Russia Northern (Arctic) Federal University Arkhangelsk 163002 Russia

The search is now on for new materials that can be used for ionic stripping. Materials that maximize the stripping of the structural ion are important for conducting experiments with quark-gluon plasma. Although this paper is a theoretical study, it offers practical applications, in heavy-ion accelerators, of the new effect of collision multiplicity with high-energy ions interacting with polyatomic targets. It is shown that internal nanostructured targets in which the collision multiplicity effect is manifested can more efficiently strip out structural ions compared to standard internal targets for stripping. A target consisting of oriented nano-tubes with the C_（240） chirality（10,0）is considered as an example. A comparison with the stripping process on a carbon target with the same number of misaligned atoms in a unit of volume C is provided.

关键词： ion stripping accelerator target ion beam nanotube charge composition

Dispersion of ventricular repolarization: Temporal and spatial

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World Journal of Cardiology 2020年第9期12卷 437-449页

作者： Natalia v Arteyeva Laboratory of Cardiac Physiology Institute of Physiology of Komi Science Centre of the Ural Branch of the Russian Academy of SciencesSyktyvkar 167982Russia

Repolarization heterogeneity(RH)is an intrinsic property of ventricular myocardium and the reason for T-wave formation on electrocardiogram(ECG).Exceeding the physiologically based RH level is associated with appearance of life-threatening ventricular arrhythmias and sudden cardiac *** this regard,an accurate and comprehensive evaluation of the degree of RH parameters is of importance for assessment of heart state and arrhythmic *** review is devoted to comprehensive consideration of RH phenomena in terms of electrophysiological processes underlying RH,cardiac electric field formation during ventricular repolarization,as well as clinical significance of RH and its reflection on ECG *** formation of transmural,apicobasal,left-toright and anterior-posterior gradients of action potential durations and end of repolarization times resulting from the heterogenous distribution of repolarizing ion currents and action potential morphology throughout the heart ventricles,and the different sensitivity of myocardial cells in different ventricular regions to the action of pharmacological agents,temperature,frequency of stimulation,etc.,are being *** review is focused on the fact that RH has different aspects–temporal and spatial,global and local;ECG reflection of various RH aspects and their clinical significance are being *** for comprehensive assessment of ventricular RH using different ECG indices reflecting various RH aspects are presented.

关键词： Temporal Spatial Global and local dispersion of repolarization Action potential duration Tpeak-Tend interval Tpeak-Tend dispersion T-vector Arrhythmogenesis

Electron-beam Treatment of Tungsten-free TiC/NiCr Cermet Ⅰ:Influence of Subsurface Layer Microstructure on Resistance to Wear during Cutting of Metals

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Journal of Materials Science & Technology 2005年第3期21卷 427-429页

作者： v.E.Ovcharenko BaohaiYU S.G.Psakhie InstituteofStrengthPhysicsandMaterialsScience SiberiaBranchRussianAcademyofSciences2/1AcademicheskyPr.Tomsk634021Russia InstituteofMetalResearch ChineseAcademyofSciences72WenhuaRoadShenyang110016China

An experimental investigation were performed on the effect of the impulse electron-beam irradiation upon microstruc-ture of the surface layer and on wear resistance of a cutting tool for sintered TiC/NiCr cermet. The results showed that the surface electron-beam treatment of the TiC/NiCr cermet is an efficient method for investigating the mi-crostructure and phase composition in the surface layer of the powder composite and there are optimal regimes of electron-beam treatment, which ensure a substantial increase in the resistance of the cermet to wear during cutting of metals.

关键词： Cermet TiC/NiCr Electron-beam treatment Microstructure Wear resistance

Application of an LC–MS/MS method for the analysis of amlodipine,valsartan and hydrochlorothiazide in polypill for a bioequivalence study

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Journal of Pharmaceutical Analysis 2017年第5期7卷 309-316页

作者： Jaivik v.Shah Jignesh M.Parekh Priyanka A.Shah Priya v.Shah Mallika Sanyal Pranav S.Shrivastav Department of Chemistry School of Sciences Gujarat University Department of Chemistry St.Xavier's College Department of Pharmacy M.S.University

A sensitive and selective method has been proposed for the simultaneous determination of amlodipine(AML),valsartan(vAL) and hydrochlorothiazide(HCTZ) in human plasma by liquid chromatography–tandem mass spectrometry(LC–MS/MS). The analytes and their deuterated analogs were quantitatively extracted from100 μL human plasma by solid phase extraction on Oasis HLB cartridges. The chromatographic separation of the analytes was achieved on a Chromolith RP18 e(100 mm × 4.6 mm) analytical column within 2.5 min. The resolution factor between AML and vAL, AML and HCTZ, and vAL and HCTZ was 2.9, 1.5 and 1.4, respectively,under isocratic conditions. The method was validated over a dynamic concentration range of 0.02–20.0 ng/m L for AML, 5.00–10,000 ng/m L for vAL and 0.20–200 ng/m L for HCTZ. ion-suppression/enhancement effects were investigated by post-column infusion technique. The mean IS-normalized matrix factors for AML, vAL and HCTZ were 0.992, 0.994 and 0.998, respectively. The intra-batch and inter-batch precision(% Cv) across quality control levels was ≤ 5.56% and the recovery was in the range of 93.4%–99.6% for all the analytes. The method was successfully applied to a bioequivalence study of 5 mg AML + 160 mg vAL + 12.5 mg HCTZ tablet formulation(test and reference) in 18 healthy Indian males under fasting. The mean log-transformed ratios of C max, AUC0–120 h and AUC0-inf and their 90% CIs were within 90.2%–102.1%. The assay reproducibility was demonstrated by reanalysis of 90 incurred samples.

关键词： Amlodipine valsartan Hydrochlorothiazide LC–MS/MS Polypill Bioequivalence

Structural,phonon,elastic,thermodynamic and electronic properties of Mg-X(X=La,Nd,Sm)intermetallics:The first principles study

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Journal of Magnesium and Alloys 2019年第1期7卷 166-185页

作者： S.Rameshkumar G.Jaiganesh v.Jayalakshmi Department of Physics SRM Institute of Science and TechnologyRamapuram CampusChennai 600089India Materials Science Group Indira Gandhi Centre for Atomic ResearchKalpakkam 603102India

We show the results of first-principles calculations of structural,phonon,elastic,thermal and electronic properties of the Mg-X inter-metallics in their respective ground state phase and meta-stable phases at equilibrium geometry and the studied pressure *** dispersion spectra for these compounds were investigated by using the linear response *** phonon spectra do not show any abnormality in their respective ground state *** respective ground states phases of the studied system remain stable within the studied pressure *** and thermodynamic properties were derived by analysis of the electronic structures and quasi-harmonic *** mixed bonding character of the Mg-X intermetallics is revealed by Mg-X bonds,and it leads the metallic *** of the contribution originated from X ions d like states at Fermi level compared to that of Mg ion in these *** this work,we also predicted the melting temperature of these intermetallics and evaluated the Debye temperature by using elastic constants.

关键词： Mg-X intermetallics First principle calculation Heat of formation Elastic constants Electronic and phonon properties Thermodynamic property

Assessing the performance of YOLOv5 algorithm for detecting volunteer cotton plants in corn fields at three different growth stages

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Artificial Intelligence in Agriculture 2022年第1期6卷 292-303页

作者： Pappu Kumar Yadav J.Alex Thomasson Stephen W.Searcy Robert G.Hardin Ulisses Braga-Neto Sorin C.popescu Daniel E.Martin Roberto Rodriguez Karem Meza Juan Enciso Jorge Solórzano Diaz Tianyi Wang Department of Biological&Agricultural Engineering Texas A&M UniversityCollege StationTXUnited States of America Department of Agricultural&Biological Engineering Mississippi State UniversityMississippi StateMSUnited States of America Department of Electrical&Computer Engineering Texas A&M UniversityCollege StationTXUnited States of America Department of Ecology&Conservation Biology Texas A&M UniversityCollege StationTXUnited States of America Aerial Application Technology Research U.S.D.A.Agriculture Research ServiceCollege StationTXUnited States of America U.S.D.A.-APHIS PPQ S&T Mission LabEdinburgTXUnited States of America Department of Civil&Environmental Engineering Utah State UniversityLoganUTUnited States of America Texas A&M AgriLife Research&Extension Center WeslacoTXUnited States of America College of Engineering China Agricultural UniversityBeijingChina

The feral or volunteer cotton(vC)plants when reach the pinhead squaring phase(5–6 leaf stage)can act as hosts for the boll weevil(Anthonomus grandis L.)*** Texas Boll Weevil Eradication Program(TBWEP)employs people to locate and eliminate vC plants growing by the side of roads or fields with rotation crops but the ones growing in the middle of fields remain *** this paper,we demonstrate the application of computer vision(Cv)algorithm based on You Only Look Once version 5(YOLOv5)for detecting vC plants growing in the middle of corn fields at three different growth stages(v3,v6 and vT)using unmanned aircraft systems(UAS)remote sensing *** the four variants of YOLOv5(s,m,l,and x)were used and their performances were compared based on classification accuracy,mean average precision(mAP)and *** was found that YOLOv5s could detect vC plants with maximum classification accuracy of 98%and mAP of 96.3%at v6 stage of corn while YOLOv5s and YOLOv5m resulted in the lowest classification accuracy of 85%and YOLOv5m and YOLOv5l had the least mAP of 86.5%at vT stage on images of size 416×416 *** developed Cv algorithm has the potential to effectively detect and locate vC plants growing in the middle of corn fields as well as expedite the management aspects of TBWEP.

关键词： Boll weevil volunteer cotton plant Computer vision YOLOv5 Unmanned aircraft systems(UAS) Remote sensing

Formation of Nanoscale Intermetallic Phases in Ni Surface Layer at High Intensity Implantation of Al ions

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Journal of Materials Science & Technology 2004年第5期20卷 583-586页

作者： I.A.Bozhko S.v.Fortuna I.A.Kurzina I.B.Stepanov E.v.Kozlov Yu.P.Sharkeev Tomsk State University of Architecture & Building 2 Solyanaya pl.Tomsk 634003RussiaTomsk State University of Architecture & Building2 Solyanaya pl.Tomsk 634003RussiaTomsk State University of Architecture & Building2 Solyanaya pl.Tomsk 634003RussiaNuclear Physics InstituteTomsk Polytechnic University2a Lenin Str.Tomsk 634050RussiaTomsk State University of Architecture & Building2 Solyanaya pl.Tomsk 634003.RussiaInstitute of Strength Physics and Materials ScienceRussian Academy of Sciences2/1 Pr.AkademicheskiiTomsk 634021Russia

The results of experimental study of nanoscale intermetallic formation in surface layer of a metal target at ion implantation are presented. To increase the thickness of the ion implanted surface layer the high intensive ion implantation is used. Compared with the ordinary ion implantation, the high intensive ion implantation allows a much thicker modified surface layer. Pure polycrystalline nickel was chosen as a target. Nickel samples were irradiated with Al ions on the vacuum-arc ion beam and plasma flow source 'Raduga-5'. It was shown that at the high intensity ion implantation the fine dispersed particles of Ni3AI, NiAl intermetallic compounds and solid solution Al in Ni are formed in the nickel surface layer of 200 nm and thicker. The formation of phases takes place in complete correspondence with the Ni-AI phase diagram.

关键词： High intensive ion implantation ion-plasma source Intermetallic nanophases

Conversion of an atomic to a molecular argon ion and low pressure argon relaxation

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Chinese Physics B 2016年第1期25卷 697-705页

作者： M N Stankov A P Jovanovie v Lj Markovic S N Stamenkovic Department of Physics Faculty of Sciences and MathematicsUniversity of Ni Viegradska 33Ni 18001Serbia

The dominant process in relaxation of DC glow discharge between two plane parallel electrodes in argon at pressure 200 Pa is analyzed by measuring the breakdown time delay and by analytical and numerical models. By using the approx- imate analytical model it is found that the relaxation in a range from 20 to 60 ms in afterglow is dominated by Ar＋ ions, produced by atomic-to-molecular conversion of Ar＋ ions in the first several milliseconds after the cessation of the discharge. This conversion is confirmed by the presence of double-Gaussian distribution for the formative time delay, as well as con- version maxima in a set of memory curves measured in different conditions. Finally, the numerical one-dimensional （1D） model for determining the number densities of dominant particles in stationary DC glow discharge and two-dimensional （2D） model for the relaxation are used to confirm the previous assumptions and to determine the corresponding collision and transport coefficients of dominant species and processes.

关键词： argon discharge afterglow relaxation fluid model plasma reactions