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Reduction of CeO2 in composites with transition metal complex oxides under hydrogen containing atmosphere and its correlation with catalytic activity

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Frontiers of Chemical Science and Engineering 2013年第3期7卷 249-261页

作者： elena yu. KONYSHEVA School of Chemistry University of St Andrews KY169ST St Andrews Fife UK Department of Chemistry Xi'an Jiaotong-Liverpool University Suzhou 215123 China

Reduction behavior of pure and doped CeO2, the multi-phase ***2, ***0.2MnO3 . xCeO2, and ***2 composites, was studied under hydrogen containing atmosphere to address issues related to the improvement of electrochemical and catalytic performance of electrodes in fuel cells. The enhanced reduction of cerium oxide was observed initially at 800~C in all composites in spite of the presence of highly reducible transition metal cations that could lead to the increase in surface concentration of oxygen vacancies and generation of the electron enriched surface. Due to continuous reduction of cerium oxide in La0.6Sr0.4CoO3 ＂x- CeO2 and ***3 ＂xCeO2 （up to 10 h） composites the redox activity of the Ce4＋/Ce3＋ pair could be suppressed and additional measures are required for reversible spontaneous regeneration of Ce4＋. After 3 h exposure to H2-Ar at 800~C the reduction of cerium oxides and perovskite phases in La0.95Ni0.6Fe0.403 ＂xCeO2 com- posites was diminished. The extent of cerium oxide involvement in the reduction process varies with time, and depends on its initial deviation from oxygen stoichiometry （that results in the larger lattice parameter and the longer pathway for O2 transport through the fluorite lattice）, chemical origin of transition metal cations in the perovskite, and phase diversity in multi-phase composites.

关键词： reduction of cerium oxide composites perovskites catalyst under hydrogen containing atmosphere

Palladium installed copper-organic framework for C–C coupling reactions

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Science China Chemistry 2025年

作者： yu.Mei Wang Mei-Xia Tao Kai-Ming Mo Xu Chen Shu-Hua Zhong elena S Shubina Guo-Hong Ning Dan Li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Supramolecular Coordination ChemistryJinan University A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences

The formation of C–C bonds is a crucial aspect of organic synthesis. Synthesists' long-term objective is to identify novel catalysts to optimize reaction systems based on traditional transition metal catalysis. This study explores the synthesis and catalytic potential of palladium-installed covalent metal-organic frameworks(CMOFs) based on copper cyclic trinuclear units(Cu-CTUs). By incorporating palladium ions into the imine-based framework JNM-7 through a straightforward immersion method, we achieved a notable enhancement in catalytic activity for critical C–C coupling reactions, including C–H arylation and Sonogashira cross-coupling. The resulting JNM-7-Pd demonstrated remarkable stability and recyclability, maintaining its efficiency over at least three cycles without any decline in efficiency.

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Subsolidus Conceptual Design of CaO-AI_2O_3-TiO_2-SiO_2 System and Its Significance for Manufacturing Advanced Ceramics

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China's Refractories 2016年第1期25卷 44-52页

作者： Michail I. RYSCHENKO Yaroslav N. PITAK elena yu. FEDORENKO Maria yu. LISyu.KINA Alexey V. SHEVTSOV National Technical University "Kharkiv Polytechnic Institute" Kharkov 61002 Ukraine

The article deals the structure of the CaO -Al2O3 - TiO2 -SiO2 system as a basis for obtaining advanced ce- ramics with a complex of high-operational characteris- tics. As a result o[＇investigations the phase charctcteristics are represented trod the graph of the relationship of the elementaory tetrahedra has been plotted. The most techno- logical system area ,for the production of heat resistant advanced ceramics has been determined. The batches for producing heat and chemical resistant dense advanced ceramics made of natural, technical and technogenic raw materials have been developed.

关键词： geometric - topological characteristics thermodynamic analysis resource conservation ceramic eomprising tialite sintering processes phase formation

Shape estimation for a TPU-based multi-material 3D printed soft pneumatic actuator using deep learning models

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Science China(Technological Sciences) 2024年第5期67卷 1470-1481页

作者： HU yu.TANG Wei QU Yang XU HuXiu KRAMARENKO yu.elena ZOU Jun State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310058China School of Mechanical Engineering Zhejiang UniversityHangzhou310027China Institute of Process Equipment College of Energy EngineeringZhejiang UniversityHangzhou310027China Faculty of Physics Lomonosov Moscow State UniversityMoscow119991Russia Enikolopov Institute of Synthetic Polymeric Materials of Russian Academy of Sciences Moscow117393Russia

Real-time proprioception presents a significant challenge for soft robots due to their infinite degrees of freedom and intrinsic *** studies mostly focused on specific sensors and *** is still a lack of generalizable technologies for integrating soft sensing elements into soft actuators and mapping sensor signals to proprioception *** tackle this problem,we employed multi-material 3D printing technology to fabricate sensorized soft-bending actuators(SBAs)using plain and conductive thermoplastic polyu.ethane(TPU)*** designed various geometric shapes for the sensors and investigated their strain-resistive performance during *** address the nonlinear time-variant behavior of the sensors during dynamic modeling,we adopted a data-driven approach using different deep neural networks to learn the relationship between sensor signals and system states.A series of experiments in various actuation scenarios were conducted,and the results demonstrated the effectiveness of this *** sensing and shape prediction steps can run in real-time at a frequency of50 Hz on a consumer-level ***,a method is proposed to enhance the robustness of the learning models using data augmentation to handle unexpected sensor *** the methods are efficient,not only for in-plane 2D shape estimation but also for out-of-plane 3D shape *** aim of this study is to introduce a methodology for the proprioception of soft pneumatic actuators,including manufacturing and sensing modeling,that can be generalized to other soft robots.

关键词： shape estimation soft sensors and actuators 3D printing deep learning in robotics

Influence of Pt/Pd state on ceria-based support in CO oxidation

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Journal of Rare Earths 2023年第12期41卷 1963-1968,I0005页

作者： Igor V.Zagaynov elena yu.Liberman Alexander V.Naumkin A.A.Baikov Institute of Metallurgy and Materials Science MoscowRussia D.I.Mendeleev University of Chemical Technology of Russia MoscowRussia A.N.Nesmeyanov Institute of Organoelement Compounds MoscowRussia

Noble metal(M:Pt,Pd,PtPd) supported on ceria system catalysts were *** oxidized and reduced forms of the active component were examined in CO *** catalysts become more active after a reduction pretreatment,which shifts the temperature of CO *** of the data obtained from characterization techniques indicates that the strong interaction of metal ions with the support prevent the reduction of the initial MO_(x)to metallic *** formation of M-ceria interfaces efficiently boosts the oxygen activation during CO oxidation,leading to the formation of chemisorbed O on M and the regeneration of the ceria lattice oxygen,thus greatly improving the catalytic performance.

关键词： Ceria Platinum Palladium CO oxidation Rare earths

Activation of Auditory Centers during Freezing Response Depends on Visual Afferentation in Course of the Development of Pied Flycatcher Nestlings

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Journal of Behavioral and Brain Science 2019年第11期9卷 385-393页

作者： elena Korneeva Anna Tiunova Leonid Alexandrov Tatyana golubeva Institute of Higher Nervous Activity and Neurophysiology Moscow Russia P.K. Anokhin Institute of Normal Physiology Moscow Russia Biology Dept. Moscow State University Moscow Russia

The study of defense behavior development in pied flycatcher altricial nestlings has shown that preceding visual deprivation decreased the capability to freeze in the young. At the same time, auditory thresholds of deprived nestlings were lower than those of the nestlings developing in unaltered visual environment. Our goal in the present work was to study effects of visual input on the functional development of neural circuitry for flycatcher’s acoustically-guided defensive behavior. We compared the immunohistochemical response of transcription factors ZENK and c-Fos in the nestlings’ auditory telencephalic structures in visually deprived and non-deprived flycatcher nestlings to alarm calls emitted by adult birds. We have demonstrated that the development of flycatcher nestlings under the conditions of limited visual afferentation results in the decrease of induction of the immediate-early genes c-Fos and ZENK in auditory structures of 9-day-old nestlings performing auditory-guided defense behavior. The most marked decrease of induction of both genes is observed in Field L. Our data suggest that visual afferentation affects neuronal activations in higher auditory structures of nestlings’ brain that, in turn, may increase the efficiency of species-typical alarm call. Thus, the work demonstrated for the first time that visual affererntation facilitates the growth of efficiency of alarm call affecting the activity of neurons in auditory integrative structures.

关键词： Defense Behavior Freezing Alarm Call Visual Deprivation Flycatcher Nestlings ZENK c-Fos

Size-dependent gene delivery of amine-modified silica nanoparticles

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Nano Research 2016年第2期9卷 291-305页

作者： Meihua yu.yu.ing Niu Jun Zhang Hongwei Zhang Yannan Yang elena Taran Siddharth Jambhrunkar Wenyi Gu Peter Thorn Chengzhong yu Australian Institute for Bioengineering and Nanotechnology The University of Queensland Brisbane QLD 4072 Australia Australian National Fabrication Facility-QLD Node Brisbane QLD 4072 Australia School of Biomedical Sciences The University of Queensland Brisbane QLD 4072 Australia

Silica-based nanoparticles are promising carriers for gene delivery applications. To gain insights into the effect of particle size on gene transfection efficiency, amine-modified monodisperse St6ber spheres （NH2-SS） with diameters of 125, 230, 330, 440, and 570 nm were synthesized. The in vitro transfection efficiencies of NH2-SS for delivering plasmid DNA encoding green fluorescent protein （GFP）（pcDNA3-EGFP, abbreviated as pcDNA, 6.1 kbp） were studied in HEK293T cells. NH2-SS with a diameter of 330 nm （NH2-SS330） showed the highest GFP transfection level compared to NH2-SS particles with other sizes. The transfection efficiency was found as a compromise between the binding capacity and cellular uptake performance of NH2-SS330 and pcDNA conjugates. NH2-SS330 also demonstrated the highest transfection efficiency for plasmid DNA （pDNA） with a bigger size of 8.9 kbp. To our knowledge, this study is the first to demonstrate the significance of particle size for gene transfection efficiency in silica-based gene delivery systems. Our findings are crucial to the rational design of synthetic vectors for gene therapy.

关键词： silica nanoparticles gene delivery plasmid DNA particle sizes cellular uptake

Features of Internal Waves in a Shoaling Thermocline

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International Journal of Geosciences 2013年第5期4卷 871-879页

作者： Vadim V. Navrotsky Valeriy yu. Liapidevskii elena P. Pavlova M.A. Lavrentiev Institute of Hydrodynamics Siberian Branch of Russian Academy of Sciences Novosibirsk Russia V.I.Il’ichev Pacific Oceanological Institute Far-Eastern Branch of Russian Academy of Sciences Vladivostok Russia

Observations and numeric modeling of internal wave generation and transformation in the shelf zone of sea show that the main part of tidal energy is transported to shores in form of internal gravitational waves. Long-term measurements of temperature and current velocity fluctuations at many levels in the near-bottom thermocline were carried out during the periods when stable seasonal thermocline was present. Analysis of the measurements permits us to understand mechanisms of internal wave destruction with turbulent motion generation and corresponding rebuilding of velocity and density mean fields in the stratified near-bottom layer. Spectral analysis of temperature fluctuations shows that in shoaling internal waves the low-frequency maxima disappear, maxima at higher frequencies appear, and the spectra slope in the high frequency range changes with depth. Taking into account the concurrent analysis of near-bottom pressure fluctuations and current velocity fluctuations from surface till bottom we come to the conclusion that breaking internal waves in a near-bottom thermocline generate not only small-scale three-dimensional turbulence, but also quasi-horizontal turbulence of larger scales, which considerably contributes into mixing and sediments, alluvium, and nutrients transport in the shelf zone of sea.

关键词： Shelf Shoaling Thermocline Internal Waves Turbulence

3D model of Svecofennian Accretionary Orogen and Karelia Craton based on geology,reflection seismics,magnetotellurics and density modelling:Geodynamic speculations

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Geoscience Frontiers 2020年第3期11卷 999-1023页

作者： Michael V.Mints Victor N.Glaznev Olga M.Muravina elena yu.Sokolova Geological Institute RASMoscowRussia Voronezh State University VoronezhRussia Schmidt Institute of Physics of the Earth RASMoscowRussia All-Russian Research Geological Oil Institute MoscowRussia

A 3D model of deep crustal structure of the Archaean Karelia Craton and late Palaeoproterozoic Svecofennian Accretionary Orogen including the boundary zone is *** model is based on the combination of data from geological mapping and reflection seismic studies,along profiles 1-EU,4 B,FIRE-1-2 a-2 and FIRE-3-3 a,and uses results of magnetotelluric soundings in southern Finland and northern Karelia.A seismogeological model of the crust and crust-mantle boundary is compared with a model of subhorizontal velocity-density layering of the *** TTG-type crust of the Palaeoarchaean and Mesoarchaean microcontinents within the Karelia Craton and the Belomorian Province are separated by gently dipping greenstone belts,at least some of which are *** structure of the crust was determined mainly by Palaeoproterozoic tectonism in the intracontinental settings modified by a strong collisional compression at the end of the *** insights into structure,origin and evolution of the Svecofennian Orogen are *** accretionary complex is characterized by inclined tectonic layering:the tectonic sheets,~15 km thick,are composed of volcanic-sedimentary rocks,including electro-conductive graphite-bearing sedimentary rocks,and electro-resistive granitoids,which plunge monotonously and consecutively *** reaching the level of the lower crust,the tectonic sheets of the accretionary complex lose their distinct *** the seismic reflection pattern they are replaced by a uniform acoustically translucent medium,where separate sheets can only be traced *** crust-mantle boundary bears a diffuse character:the transition from crust to mantle is recorded by the disappearance of the vaguely drawn boundaries of the tectonic sheets and in the gradual transition of acoustically homogeneous and translucent lower crust into transparent *** the effect of endogenic heat flow,the accretionary complex underwent high-temperatu

关键词： Reflection seismics Magnetotellurics Svecofennian accretionary Orogen Svecofennian Ocean 3D crustal model Velocity-density layering