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熵增工程在电催化反应中的研究进展

物理化学学报 2024年第7期40卷 36-42页

作者：张新义任楷刘妍宁谷振一黄志雄郑硕航王晓彤郭晋芝 Igor v.Zatovsky 曹峻鸣吴兴隆东北师范大学化学学院长春130024 东北师范大学紫外光发光材料与技术教育部重点实验室长春130024 乌克兰国家科学院生物胶体化学研究所乌克兰基辅03142

目前对高性能与高稳定性的电催化剂进行精准合成仍然是亟待解决的问题。熵作为是最重要的热力学参数之一,是描述体系无序程度的物理量,其数值主要由材料的结构、磁矩、原子和电子振动共同决定。根据体系的构型熵值,我们通常将材料分为... 详细信息

目前对高性能与高稳定性的电催化剂进行精准合成仍然是亟待解决的问题。熵作为是最重要的热力学参数之一,是描述体系无序程度的物理量,其数值主要由材料的结构、磁矩、原子和电子振动共同决定。根据体系的构型熵值,我们通常将材料分为低熵材料(Δs_(mix)s_(mix)≥1.5R)和高熵材料(Δs_(mix)>1.5R)。随着熵值的增加,材料本征的物理与化学性质也会随之发生相应的变化。得益于不同金属元素的共存,在界面处原子级的多组分排列,所产生的协同性高熵效应能够有效地提升电催化反应的活性,因此在电催化领域中得到了广泛的研究关注。本综述对高熵电催化剂的基本概念、合成路线(“自上而下”与“自下而上”)以及在不同电催化反应类型中的高熵材料结构与性能之间的构效关系进行了系统总结,主要包括析氢(HeR)、析氧(oeR)、氧还原(oRR)、醇氧化(AoR)、氮还原(nRR)和二氧化碳还原反应(Co_(2)RR)等,从而阐明熵增工程对高性能电催化剂设计与应用的优势与潜力。同时,针对目前高熵催化剂研究所面临的主要问题与挑战,对未来基于熵增工程的高熵电催化剂的设计思路与合成方法进行展望。

关键词：熵增合成电化学高熵催化剂电催化

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Comparative investigations of structure and properties of micro-arc wollastonite-calcium phosphate coatings on titanium and zirconiumniobium alloy

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bioactive Materials 2017年第3期2卷 177-184页

作者： M.b.sedelnikova e.g.Komarova yu.p.sharkeev T.v.Tolkacheva I.A.Khlusov L.s.Litvinova K.A.yurova v.v.shupletsova Institute of strength physics and Materials science of sb RAs Academicheskii pr.2/4634055TomskRussia national Research Tomsk polytechnic University Lenina pr.30634050TomskRussia siberian state Medical University 2 Moskovsky tr.634050TomskRussia Immanuel Kant baltic Federal University 14 A.Nevskogo st.236041KaliningradRussia

Investigation results of micro-arc wollastoniteecalcium phosphate(W-Cap)biocoatings on the pure titanium(Ti)and Zr-1wt.%nb(Zr-1nb)alloy were *** voltages of 150-300 v generate the micro-arc oxidation(MAo)process with the initial amplitude current of 150-550 A and 100-350 A for Ti and Zr-1nb substrates,*** identical dependencies of changes of the coating thickness,surface roughness and adhesion strength on the process voltage were revealed for the both *** W-Cap coatings with the thickness of 10-11μm were formed on Ti and Zr-1nb under the low process voltage of 130-150 *** wollastonite particles with the size in the range of 40-100μm were observed in such *** structure of the coatings on Ti was presented by the X-ray amorphous and crystalline *** X-ray reflexes relating to the crystalline phases of Ti and wollastonite were observed only in XRD patterns of the coatings deposited under 130-200 v on ***,the crystalline structure with phases of CaZr4(po4)6,β-Zrp2o7,Zro2,and Zr was detected in the coatings on ***-IRs,XRD,seM,and TeM data confirmed that the increase of the process voltage to 300 v leads to the dissociation of the *** toxic effect of specimens on a viability,morphology and motility of human adipose-derived multipotent mesenchymal stem cells was revealed in vitro.

关键词： Micro-arc oxidation biocoatings Calcium phosphate Wollastonite

phlogopite in mantle xenoliths and kimberlite from the grib pipe,Arkhangelsk province,Russia:evidence for multi-stage mantle metasomatism and origin of phlogopite in kimberlite

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geoscience Frontiers 2019年第5期10卷 1941-1959页

作者： A.v. Kargin L.v. sazonova A.A. nosova n.M. Lebedeva yu.A. Kostitsyn e.v. Kovalchuk v.v. Tretyachenko Ya.s. Tikhomirova Institute of geology of ore Deposits PetrographyMineralogyand GeochemistryRussian Academy of Sciences (IGEM RAS)MoscowRussia Lomonosov Moscow state University MoscowRussia vernadsky Institute of geochemistry and Analytical Chemistry of Russian Academy of sciences MoscowRussia AC ALRosA Research geological prospecting enterprise ArkhangelskRussia

We present petrography and mineral chemistry for both phlogopite,from mantle-derived xenoliths (garnet peridotite,eclogite and clinopyroxene-phlogopite rocks) and for megacryst,macrocryst and groundmass flakes from the grib kimberlite in the Arkhangelsk diamond province of Russia to provide new insights into multi-stage metasomatism in the subcratonic lithospheric mantle (sCLM) and the origin of phlogopite in *** on the analysed xenoliths,phlogopite is characterized by several *** first generation (phl1) occurs as coarse,discrete grains within garnet peridotite and eclogite xenoliths and as a rock-forming mineral within clinopyroxene-phlogopite *** second phlogopite generation (phl2) occurs as rims and outer zones that surround the phl1 grains and as fine flakes within kimberlite-related veinlets filled with carbonate,serpentine,chlorite and *** garnet peridotite xenoliths,phlogopite occurs as overgrowths surrounding garnet porphyroblasts,within which phlogopite is associated with Cr-spinel and minor *** eclogite xenoliths,phlogopite occasionally associates with carbonate bearing veinlet ***,from the kimberlite,occurs as megacrysts,macrocrysts,microcrysts and fine flakes in the groundmass and matrix of kimberlitic *** phlogopite grains within the kimberlite are characterised by signs of deformation and form partly fragmented grains,which indicates that they are the disintegrated fragments of previously larger ***1,within the garnet peridotite and clinopyroxeneephlogopitexenoliths,is characterised bylow Ti and Cr contents (Tio2o3ndMg#=100×Mg/(MgtFe)>92) typical of primary peridotite phlogopite in mantle peridotite xenoliths from global kimberlite *** formed during sCLM metasomatism that led to a transformation from garnet peridotite to clinopyroxene-phlogopite rocks and the crystallisation of phlogopite and high-Cr clinopyroxene megacrysts before the

关键词： Mantle metasomatism Kimberlite phlogopite Mantle xenoliths Megacrysts

effect of Tio_(2) nanoparticles on the photocatalytic properties of peo coatings on Mg alloy

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Journal of Magnesium and Alloys 2023年第2期11卷 735-752页

作者： D.v.Mashtalyar I.M.Imshinetskiy K.v.nadaraia A.s.gnedenkov s.n.suchkov D.p.opra e.v.pustovalov A.yu Ustinov s.L.sinebryukhov s.v.gnedenkov Institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok690022Russia Far eastern Federal University Vladivostok690950Russia

A comprehensive study of the properties of coatings formed on a magnesium alloy by plasma electrolytic oxidation(peo) using the electrolytes with nanosized particles of anatase(titanium dioxide) has been carried out. Formed coatings reduce corrosion current density 2.5-fold and increase hardness by 25% compared to a coating without particles. Confocal micro-Raman spectroscopy revealed the presence of anatase and rutile phases in the composition of peo coating due to the incorporation of Tio2nanoparticles during plasma electrolytic treatment. The presence of titanium dioxide had a positive effect on the photocatalytic properties of coatings: the constant rate of the methyl orange and methyl blue decomposition is increased in 1.6 and 1.8-fold, respectively, compared to the coating formed in electrolyte without Tio_(2) particles.

关键词： plasma electrolytic oxidation nanoparticles Titanium dioxide photocatalysis protective coatings

Development of Zeff diagnostic system on the globus-M（M2） tokamak and the first experimental results

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plasma science and Technology 2019年第10期21卷 33-39页

作者： e A TUKHMenevA s yu ToLsTYAKov g s KURsKIev v K gUsev v b MInAev yu v peTRov n v sAKHARov A yu TeLnovA n n bAKHARev p b sHegoLev e o KIseLev Ioffe Institute

studying the behavior of effective ion charge Zeff, which indicates the degree of pollution of plasma and can provide valuable information about many processes taking place in plasma, mechanisms of the releasing impurities, transport, etc is of great interest. This paper describes the development of the Zeff diagnostic system for the globus-M2 tokamak. The effective ion charge is determined on the basis of measurements of the bremsstrahlung intensity and Thomson scattering data-Te and ne profiles. The results of the first Zeff measurements obtained for several discharges on the globus-M tokamak are presented in this paper. The results have been validated by simulation using the AsTRA transport code for the same discharges, and it has demonstrated a good agreement with the experimental results.

关键词： tokamak effective ion charge magnetic confinement

Response of wild Avena species to fungal infection of grain

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The Crop Journal 2017年第6期5卷 499-508页

作者： T.yu.gagkaeva o.p.gavrilova A.s.orina e.v.blinova I.g.Loskutov All-Russian Institute of plant protection (vIZR) St-Petersburg Pushkin 196608 Russia n.I.vavilov All-Russian Institute of plant genetic Resources (vIR) St-Petersburg 190000 Russia st-petersburg state University St-Petersburg 199034 Russia

sixty-six accessions belonging to Avena species(A. atlantica, A. canariensis, A. clauda, ***, A. hirtula, A. longiglumis, A. wiestii, A. agadiriana, A. barbata, A. vaviloviana, ***, A. magna, A. murphyi, ***, A. ludoviciana, A. occidentalis, A. sterilis, A. sativa, and A. byzantina) obtained from the n. I. vavilov Institute of plant genetic Resources(vIR) were tested for the infection of grain by Alternaria and Cladosporium at the genus level and by a group of trichothecene-producing Fusarium fungi. Real-time pCR was performed to quantify fungal abundance and eLIsA was performed for mycotoxin analysis in grain. The average amounts of all tested fungi in tetraploid Avena species were higher than those in diploid and hexaploid species. Low amounts of deoxynivalenol(Don) were detected in seven hexaploid genotypes(A. sterilis, A. byzantina, A. sativa, and A. fatua) and one diploid genotype(***). The relationship between some morphological traits(1000-grain weight, percent of husk, trichome density, and plant height) of Avena species and grain infection by fungi and mycotoxins was investigated. Alternaria and Cladosporium fungi could not penetrate the husk. A highly negative correlation of the amounts of their DnA with the proportions of husk in grain as well as with trichome density was found. In contrast, a significant positive correlation between the amount of Fusarium DnA and these traits was found. A strong negative correlation bctween plant height and DnA of the analyzed fungi was found. The oats least infected by Alternaria, Cladosporium, and Fusarium fungi and containing low amounts of Don were accessions of the hexaploids A. byzantina, ***, A. sativa, A. sterilis,and the diploid A. lwiestii.

关键词： Auena species grain Fungal DnA Mycotoxin

Thermodynamic analysis of metal segregation in dual phase high entropy ceramics

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Journal of Materiomics 2024年第4期10卷 889-895页

作者： steven M.smith II William g.Fahrenholtz gregory e.Hilmas stefano Curtarolo Missouri University of science and Technology Materials Science and Engineering DepartmentRollaMO65409USA Duke University Department of Mechanical Engineering and Materials ScienceDurhamNC27708USA Duke University Center of Autonomous Materials DesignDurhamNC27708USA

equilibrium gibbs'free energy calculations were used to determine metal segregation trends between boride and carbide solid solutions containing two metals that are relevant to dual phase high entropy *** model predicted that Ti had the strongest tendency to segregate to the boride phase followed by Zr,nb,Mo,v,Hf,and Ta,which matches experimental results of measured *** ratio of a metal in the carbide phase to the content of the same metal in the corresponding metal boride had a linear trend with the change in standard gibbs'free energy of reaction for a metal carbide reacting with b_(4)C to produce its corresponding metal boride and *** proposed model was used to predict the changes in standard gibbs'free energy for CrC→Crb_(2) to be−260 kJ and WC→Wb_(2) to be 148 kJ,which indicates that Cr has the strongest segregation to the boride and W has the strongest segregation to the *** proposed model can be used to estimate the segregation of metals in dual phase high entropy boride-carbide ceramics of any boride/carbide ratio or metal content.

关键词： Dual phase High entropy ceramic boride Carbide Thermodynamics

second-Harmonic Response in Magnetic nodal-Line semimetal Fe3geTe2

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Chinese physics Letters 2022年第9期39卷 78-82页

作者： v.D.esin A.A.Avakyants A.v.Timonina n.n.Kolesnikov e.v.Deviatov Institute of solid state physics of the Russian Academy of sciences

We experimentally investigate second-harmonic transverse voltage response to ac electrical current for a magnetic nodal-line semimetal Fe3geTe2（FgT）. For zero magnetic field, the observed second-harmonic voltage behaves as a square of the longitudinal current, as it should be expected for nonlinear Hall effect. The magnetic field behavior is found to be sophisticated: while the first-harmonic response shows the known anomalous Hall hysteresis in FgT, the second-harmonic Hall voltage is characterized by the pronounced high-field hysteresis and flat（b-independent） region with curves touching at low fields. The high-field hysteresis strongly depends on the magnetic field sweep rate, so it reflects some slow relaxation process. For the lowest rates, it is also accomplished by multiple crossing points. similar shape of the second-harmonic hysteresis is known for skyrmion spin textures in nonlinear optics. since skyrmions have been demonstrated for FgT by direct visualization techniques, we can connect the observed high-field relaxation with deformation of the skyrmion lattice. Thus, the second-harmonic Hall voltage response can be regarded as a tool to detect spin textures in transport experiments.

关键词： Hysteresis

Development of Mg-Zn-Y-Zr casting magnesium alloy with high thermal conductivity

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Journal of Magnesium and Alloys 2021年第5期9卷 1583-1593页

作者： v.e.bazhenov A.v.Koltygin M.C.sung s.H.park yu.v.Tselovalnik A.A.stepashkin A.A.Rizhsky M.v.belov v.D.belov K.v.Malyutin national University of science and Technology“MIsis” Leninskiy pr.4Moscow 119049 Russia Lg electronics Inc. Yeoui-daeroYeongdeungpo-gu.128LG Twin TowerSeoul 07336 Republic of Korea

Magnesium alloys are used in aircraft because of their light ***,for these alloys to be applied in electronic devices,high thermal conductivities are *** high-potential compositions of Mg-Zn-Y-Zr alloys were selected by phase composition and their freezing ranges calculated using Thermo-Calc *** alloys were prepared,and their fluidity,hot tearing susceptibility,mechanical properties,and thermal conductivity were obtained and *** alloy composed of Mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr was selected for further investigation,because of its high thermal conductivity and satisfactory mechanical *** Mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr alloy’s fluidity and hot tearing susceptibility were similar to those of the widespread AZ91 commercial casting magnesium *** influence of a heat treatment regime on the microstructure,thermal conductivity,and mechanical properties of the developed alloy was also *** was established that the room temperature thermal conductivity of the Mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr alloy after aging at 300℃for 5 h was 105 W/m K^(-1).Additionally,the following tensile test results were obtained in aged condition:120 Mpa yield strength,200 Mpa ultimate tensile strength,and 4%*** utilization of solid solution heat treatment at 520℃for 8 h prior to aging can promote up to 9%increase in *** Mg-4 wt%Zn-3 wt%Y-0.3 wt%Zr casting alloy can be used as a high thermal conductivity material with industrial applications.

关键词： Magnesium alloy Mg-Zn-Y-Zr Thermal conductivity phase composition Fluidity Hot tearing susceptibility