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Learning the right channel in multimodal imaging: automated experiment in piezoresponse force microscopy

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npj Computational Materials 2023年第1期9卷 2008-2015页

作者： Yongtao Liu Rama K.vasudevan Kyle P.Kelley Hiroshi Funakubo maxim Ziatdinov Sergei v.Kalinin Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37923USA Department of Materials Science and Engineering Tokyo Institute of TechnologyYokohama 226-8502Japan Computational Sciences and Engineering Division Oak Ridge National LaboratoryOak RidgeTN 37923USA Department of Materials Science and Engineering University of TennesseeKnoxvilleTN 37996USA

We report the development and experimental implementation of the automated experiment workflows for the identification of thebest predictive channel for a phenomenon of interest in spectroscopic measurements. The approach is based on the combinationof ensembled deep kernel learning for probabilistic predictions and a basic reinforcement learning policy for channel selection. Itallows the identification of which of the available observational channels, sampled sequentially, are most predictive of selectedbehaviors, and hence have the strongest correlations. We implement this approach for multimodal imaging in piezoresponse forcemicroscopy (PFM), with the behaviors of interest manifesting in piezoresponse spectroscopy. We illustrate the best predictivechannel for polarization-voltage hysteresis loop and frequency-voltage hysteresis loop areas is amplitude in the model samples. Thesame workflow and code are applicable for any multimodal imaging and local characterization methods.

关键词： automated policy modal

Does ADS 9346 have a low-mass companion?

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Research in Astronomy and Astrophysics 2021年第11期21卷 202-212页

作者： Olga v.Kiyaeva maxim Yu.Khovritchev Agrippina M.Kulikova Natalya v.Narizhnaya Tatyana A.vasilyeva Arina A.Apetyan Central Astronomical Observatory Russian Academy of Sciences65/1 Pulkovskoye ChausseeSt.Petersburg196140Russia

Based on the photographic and CCD observations of the relative motion of the A and B components of the binary system ADS 9346 obtained with the 26-inch refractor of Pulkovo Observatory during 1979–2019,we discover an invisible companion associated with star *** of the ephemerides with the positional and spectroscopic observations allowed us to calculate the preliminary orbit of the photocenter(P=15 yr).The minimal mass of the companion is approximately 0.13 *** existence of the invisible low-mass companion is implied by the IR-excess based on IRAS *** confirm this,additional observations of the radial velocity near the periastron need to be carried out.

关键词： (stars:)binaries:visual stars:low-mass stars:individual(ADS 9346)

Machine learning prediction of activation energy in cubic Li-argyrodites with hierarchically encoding crystal structure-based(HECS)descriptors

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Science Bulletin 2021年第14期66卷 1401-1408,M0003页

作者： Qian Zhao maxim Avdeev Liquan Chen Siqi Shi Materials Genome Institute Shanghai UniversityShanghai 200444China Australian Nuclear Science and Technology Organization New Illawarra RdLucas HeightsNSW 2234Australia School of Chemistry The University of SydneySydney 2006Australia Key Laboratory for Renewable Energy Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Materials Science and Engineering Shanghai UniversityShanghai 200444China

Rational design of solid-state electrolytes(SSEs)with high ionic conductivity and low activation energy(Ea)is vital for all solid-state *** learning(ML)techniques have recently been successful in predicting Li^(+) conduction property in SSEs with various descriptors and accelerating the development of *** this work,we extend the previous efforts and introduce a framework of ML prediction for E_(a) in SSEs with hierarchically encoding crystal structure-based(HECS)*** cubic Li-argyrodites as an example,an Ea prediction model is developed to the coefficient of determination(R^(2))and rootmean-square error(RMSE)values of 0.887 and 0.02 ev for training dataset,and 0.820 and 0.02 ev for test dataset,respectively by partial least squares(PLS)analysis,proving the prediction power of *** variable importance in projection(vIP)scores demonstrate the combined effects of the global and local Li^(+) conduction environments,especially the anion size and the resultant structural changes associated with anion site *** developed E_(a) prediction model directs us to optimize and design new Li-argyrodites with lower Ea,such as Li_(6–x)PS_(5–x)Cl_(1+x)(v),Li_(6+x)PS_(5+x)Br_(1–x)(v),Li_(6+x)PS_(5+x)Br_(0.25)I_(0.75–x)(v),Li_(6+(5–n)y)P_(1–y)N_(y)S_(5)I(v),Li_(6+(5–n)y)As_(1–y)N_(y)S_(5)I(v),Li_(6+(5–n)y)As_(1–y)NySe_(5)I(v),by broadening bottleneck size,invoking site disorder and activating concerted Li+*** analysis shows great potential in promoting rational design of advanced SSEs and the same approach can be applied to other types of materials.

关键词： Solid-state electrolytes(SSEs) Hierarchically encoding crystal structurebased (HECS)descriptors Predicting activation energy Cubic Li-argyrodites Machine learning

Extended Corey-Chaykovsky reactions:transformation of 2-hydroxychalcones to benzannulated 2,8-dioxabicyclo[3.2.1]octanes and 2,3-dihydrobenzofurans

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Organic Chemistry Frontiers 2022年第3期9卷 737-744页

作者： Alexander A.Fadeev Anton S.Makarov Olga A.Ivanova maxim G.Uchuskin Igor v.Trushkov Department of Chemistry Perm State UniversityBukireva 15Perm 614990Russian Federation Department of Chemistry M.V.Lomonosov Moscow State UniversityLeninskie Gory 1-3Moscow 119991Russian Federation N.D.Zelinsky Institute of Organic Chemistry Leninsky pr.47Moscow 119334Russian Federation. D.Rogachev National Medical Research Center of Pediatric Hematology Oncology and ImmunologySamory Mashela 1Moscow 117997Russian Federation

We report the divergent synthesis of benzannulated 2,8-dioxabicyclo[3.2.1]octanes and 2,3-dihydrobenzofurans using the concept of extended Corey-Chaykovsky *** this concept,2-hydroxychalcones were treated with the Corey ylide providing highly reactive donor-acceptor cyclopropanes that were introduced in a one pot manner for further transformations.

关键词： octane donor

Highly Heat-Resistant Materials for Microelectronics:Hydrodynamic,Optical,and Conformational Properties of Fluorine Containing Poly(Amido-ortho-Hydroxy Amide)

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Journal of Wuhan University of Technology(Materials Science) 2020年第1期35卷 223-230页

作者： Irina A Strelina Liudmila I Rudaya Ol’ga v Okatova maxim N Bol’shakov Aleksey YuMarfichev Galina K Lebedeva Yuliya v Shagayko Stanislav M Ramsh Institute of Macromolecular Compounds Russian Academy of SciencesBolshoi pr.VO 31St Petersburg199004 Russia Saint-Petersburg State Institute of Technology(Technical University) Moskovskii pr.26St Petersburg190013 Russia

The polycondensation of the mixture of diamines 5,5-methylene bis(2-aminophenol) and 4,4-(hexafluoroisopropylidene)dianiline(molar ratio 0.8:0.2) with isophthaloyl dichloride was used to synthesize poly(amido-o-hydroxy amide)(POA-F)-new heat resistant binder of the composites for microelectronics. The copolymer was fractionated, its hydrodynamic, optical, and conformational properties were researched, and molecular masses(ММ) of the fractions were defined. The polydispersity index was estimated. Based on experimental data, calculation of the size of a segment of Kuhn characterizing degree of an intramolecular orientation order and value of coefficients of the equation of Mark-Kuhn-Hauvink for viscometric and diffusion data were performed. It was demonstrated that introducing 20 mol % of the monomer with-CF3-groups does not lead to any changes in conformational properties of the macromolecules and does not change the degree of intramolecular orientational order(the Kuhn segment length). Optical characteristics of POA-F solutions are virtually similar to the corresponding values for POA prepared with the use of single amine-containing component-5,5-methylene bis(2-aminophenol). The received MM distribution for POA-F(prepolymer) provided the solubility of its films in alkaline solutions. The heat resistance(τ5 and τ10-temperatures corresponding to 5% and of 10% PBO-F mass loss of a polymer) of the powders and the films of PBO, PBO-F were determined. The electrophysical parameters-dielectric permittivity(ε) and dielectric loss tangent(tan δ) of the PBO-F films decreased down to 3.30 and 0.017, in comparison 3.40 and 0.025 for PBO respectively.

关键词： poly(o-hydroxy amide) 4,4-(hexafluoroisopropylidene) dianiline Kuhn segment Mark-Kuhn-Houwink equations translational diffusion intrinsic viscosity flow birefringence

Trapped on the Roof of the World:taxonomic diversity and evolutionary patterns of Tibetan Plateau endemic freshwater snails(Gastropoda:Lymnaeidae:Tibetoradix)

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Integrative Zoology 2022年第5期17卷 825-848页

作者： maxim v.vINARSKI Parm viktor vON OHEIMB Olga v.AKSENOvA Mikhail Yu.GOFAROv Alexander v.KONDAKOv Ivan O.NEKHAEv Ivan N.BOLOTOv Laboratory of Macroecology and Biogeography Saint-Petersburg State UniversitySaint-PetersburgRussia Museum für Naturkunde-Leibniz Institute for Evolution and Biodiversity Science BerlinGermany N.Laverov Federal Center for Integrated Arctic Research of the Ural Branch of the Russian Academy of Sciences ArkhangelskRussia Department of Applied Ecology Saint-Petersburg State UniversitySaint-PetersburgRussia Northern(Arctic)Federal University ArkhangelskRussia

The high-elevation Tibetan Plateau(western China)is inhabited by a unique,though not particularly species-rich,community of *** explored the species content and evolutionary history of the Tibetan Plateau endemic freshwater snail genus *** relationships within the genus were reconstructed based on available sequence *** used a single-rate Poisson Tree Processes approach for species delimitation and compared putative species-level clades with already described *** found that the genus consists of at least 6 species,of which we described 4 as new to *** and soft body morphology was examined and the radula in Tibetoradix was described for theﬁrst *** on ourﬁndings,the diversiﬁcation of the genus did not result in a prominent morphological differentiation and a number of species can be regarded as morphologically *** species found in different drainage areas indicate relatively good passive dispersal abilities of the *** allopatric distribution of the species could result from competitive exclusion between *** absence of Tibetoradix *** the Tibetan Plateau could be explained by a scenario of an“evolutionary trap”,where adaptations to high elevation conditions prevented the taxa from a successful colonization of lower elevations.

关键词： biogeography High Asia molecular phylogenetics morphology species delimitation

Thermodynamics of order and randomness in dopant distributions inferred from atomically resolved imaging

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npj Computational Materials 2021年第1期7卷 397-405页

作者： Lukas vlcek Shize Yang Yongji Gong Pulickel Ajayan Wu Zhou Matthew FChisholm maxim Ziatdinov Rama K.vasudevan Sergei v.Kalinin Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTNUSA Joint Institute for Computational Sciences University of TennesseeKnoxvilleOak RidgeTNUSA Center for Functional Nanomaterials Brookhaven National LaboratoryBrookhavenNYUSA School of Materials Science and Engineering Beihang UniversityBeijingChina Department of Materials Science and NanoEngineering Rice UniversityHoustonTXUSA Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTNUSA

Exploration of structure-property relationships as a function of dopant concentration is commonly based on mean field theories for solid ***,such theories that work well for semiconductors tend to fail in materials with strong correlations,either in electronic behavior or chemical *** these cases,the details of atomic arrangements are generally not explored and *** knowledge of the generative physics and chemistry of the material can obviate this problem,since defect configuration libraries as stochastic representation of atomic level structures can be generated,or parameters of mesoscopic thermodynamic models can be *** obtain such information for improved predictions,we use data from atomically resolved microscopic images that visualize complex structural correlations within the system and translate them into statistical mechanical models of structure *** the significant uncertainties about the microscopic aspects of the material’s processing history along with the limited number of available images,we combine model optimization techniques with the principles of statistical hypothesis *** demonstrate the approach on data from a series of atomically-resolved scanning transmission electron microscopy images of Mo_(x)Re_(1-x)S_(2) at varying ratios of Mo/Re stoichiometries,for which we propose an effective interaction model that is then used to generate atomic configurations and make testable predictions at a range of concentrations and formation temperatures.

关键词： atomic resolved dopant

Imaging mechanism for hyperspectral scanning probe microscopy via Gaussian process modelling

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npj Computational Materials 2020年第1期6卷 1477-1483页

作者： maxim Ziatdinov Dohyung Kim Sabine Neumayer Rama K.vasudevan Liam Collins Stephen Jesse Mahshid Ahmadi Sergei v.Kalinin Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831USA Computational Sciences and Engineering Division Oak Ridge National LaboratoryOak RidgeTN 37831USA Joint Institute for Advanced Materials Department of Materials Science and EngineeringUniversity of TennesseeKnoxvilleTN 37996USA

We investigate the ability to reconstruct and derive spatial structure from sparsely sampled 3D piezoresponse force microcopy data,captured using the band-excitation(BE)technique,via Gaussian Process(GP)*** for weakly informative priors,GP methods allow unambiguous determination of the characteristic length scales of the imaging process both in spatial and frequency *** further show that BE data set tends to be oversampled in the spatial domains,with~30% of original data set sufficient for high-quality reconstruction,potentially enabling faster BE *** the same time,reliable reconstruction along the frequency domain requires the resonance peak to be within the measured *** behavior suggests the optimal strategy for the BE imaging on unknown ***,we discuss how GP can be used for automated experimentation in SPM,by combining GP regression with non-rectangular scans.

关键词： methods Gaussian weakly

, Optimization Studies on Synthesis of TKX-50

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Chinese Journal of Chemistry 2017年第1期35卷 98-102页

作者： Yulia D. Golenko maxim A. Topchiy Andrey F. Asachenko Mikhail S. Nechaev Dmitriy v. Pleshakov A. v. Topchiev Institute of Petrochemical Synthesis Russian Academy of Sciences Moscow 119991 Russian Federation Mendeleyev University Miusskaya sq. 9 Moscow 125047 Russian Federation

A systematic study of TKX-50 and ABTOX synthesis using both Klap6tke and Tselinskii modified procedures is described. The influence of temperature, moisture, acid amount and nature on the most critical synthesis step - diazidoglyoxime cyclization is shown. Experimental results show that presence of moisture in reaction mixture leads to product yield decreasing. The reaction temperature is another key parameter affecting product yield. High reaction temperature shows negative influence on the product yield in Klap6tke method. In Tselinskii procedure the yield of product grows with the reaction temperature increasing. For Klap6tke one-pot method, combination of N-methyl-2-pyrrolidone with 1,4-dioxane is the best solvent, whereas Tselinskii one-pot procedure gives high yield of product when combination of toluene with 0.5 equiv, of 1,8-diazabicyclo[5.4.0]undec-7-ene （DBU） is used. Us- ing optimized conditions one-pot five-step synthesis of TKX-50 starting from glyoxime is successfully performed and scaled up to 50 g.

关键词： TKX-50 ABTOX energetic salts tetrazoles solvent effects