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Geochemist.y of cryoconite and soils in the Central Caucasus region and its environmental implications

Journal of Mountain Science 2021年第12期18卷 3109-3124页

作者： Ivan KUSHNOV Evgeny ABAKUMOV Rust.m TEMBOTOV Vyacheslav POLYAKOV Saint petersburg st.te University 7/9 University EmbankmentSt Petersburg 199034Russian Federation Tembotov institute of Ecology of Mountain Territories Russian Academy of Sciences37-a I.Armand Str.Nalchik360051Russian Federation

Climate change and deglaciation are active processes in current changing *** the Central Caucasus region rapid degradation of glaciers is caused often by the formation of superficial blackcolored *** plays a crucial role in changing ecosyst.ms and may contribute to the formation of primary soils after glacier *** the past.20 years,the frequency of mudflows and other dangerous mountain events have increased in the Central Caucasus,which is associated with the glacial *** of tourism results in increasing of traffic,recreational activity and environment *** of the cryoconites geochemical properties in comparison with other types of sediments and local soils is crucial for invest.gation of geochemist.y and contamination st.te of superficial glacial *** environmental aspect is important in terms of the Central Caucasus settlements safety under conditions of deglaciation and anthropogenic *** sediments st.died(cryoconite,mudflow,moraine)were sampled at Garabashi and Skhelda glaciers as well as some local soils at the Baksan *** materials were invest.gated in terms of physicochemical and agrochemical *** concentrations of trace elements(Cu,Pb,Zn,Ni,Cd)were also determined and contamination indices(geoaccumulation index-Igeo,contamination factor-CF and degree of contamination-Cdegree)were used to evaluate the pollution st.tus of st.died *** obtained shows much higher content of organic carbon in soils(up to 7.82%)in comparison with cryoconite(max.1.63%)due to presence of vegetation,however,the basal respiration values in some cases were similar betweenсryoconite and soils,indicating high rates of microbial activity in a cryoconite *** was found that almost.all materials st.died have sandy *** sediments on both of the glaciers are enriched with phosphorus,high values of K_(2)O(max.298 mg·kg^(-1))and N-NH4(max.

关键词： Cryoconite Trace elements Entisols Contamination Central Caucasus

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Siberian Fan Reliefs

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Natural Science 2021年第8期13卷 372-380页

作者： Olga G. Gladysheva Alexander Yast.ebov Department of Ast.ophysics Ioffe Institute St. Petersburg Russia Krypton Ltd. Bryansk Russia

Unusual reliefs on the Earth’s surface were found in aerial photographs of East.rn Siberia in the late 20th century. These reliefs consist.of several tens (up to hundreds) of st.ipes that have arisen as a result of the dest.uction of vegetation and the surface layer of the ground. st.uctures of st.ipes are extended, ranging in size from 6 km to ≥20 km, with a width of several kilometers. Every st.ip (scratch on the ground) is roughly est.mated to be up to 50 m wide and ≥500 m long. The st.ipes st.rt from one edge of the relief and st.etch at inter-vals to the other, slightly diverging symmetrically from the central axis. It was determined that these reliefs are not associated with the movement of soil (avalanches, mudflows) or with the impact of air currents (hurricanes, st.rm, tornado). Geographically, these st.uc-tures of st.ipes are located within a circle with a radius of 770 km, described around the epicenter of the Tunguska catast.ophe.

关键词： Siberian Fan Reliefs Tunguska Catast.ophe

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Electric field-induced phase transition from the glasslike to paraelectric phase and dielectric spectra hardening in PMN single cryst.l

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Journal of Advanced Dielectrics 2023年第2期13卷 1-5页

作者： E.Koroleva A.Molokov S.Vakhrushev Ioffe institute Polytekhnicheskaya 26194021St.-PetersburgRussia

One of the key points in the physics of the relaxors is their response to the applied DC *** st.dies of this topic were made,in particular on the influence of the field on the dielectric ***,practically,in all the cases,the measurements were performed at a fixed frequency and usually with the change in the temperature at the fixed field *** this paper,we report the evolution of the dielectric spectra at low frequencies(0.1 Hzst.engthΔεand the width parameterαwere *** obtainedτ(E)andΔε(E)provide evidence of the field-induced transition from the nonpolar glass-like phase to the nonpolar paraelectric phase at around 1.5 kV/*** the paraelectric phase,very fast.hardening of the spectra was observed withτchanging from 10 s to about 10−4 *** performed analysis demonst.ated that the earlier reported positive C-V effect is completely determined by the spectra hardening,whileΔεdoes not show any change in the glass-like phase and monotonously decreases with a field increase in the paraelectric *** complete underst.nding of the microscopic origin of the observed phenomena,a detailed st.dy on the short-and long-range st.uctures at the same condition is necessary.

关键词： Relaxor ferroelectrics dielectric spectroscopy phase transition lead magnoniobate

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Scalable nanocomposite parylene-based memrist.rs:Multifilamentary resist.ve switching and neuromorphic applications

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Nano Research 2023年第2期16卷 3207-3214页

作者： Anna N.Matsukatova Artem Yu.Vdovichenko Timofey D.Patsaev Pavel A.Forsh Pavel K.Kashkarov Vyacheslav A.Demin Andrey V.Emelyanov National Research Centre“Kurchatov institute” Moscow 123182Russia Physics Department Lomonosov Moscow State UniversityMoscow 119991Russia Moscow institute of Physics and Technology DolgoprudnyjMoscow oblast 141701Russia Enikolopov institute of Synthetic Polymeric Materials Russian Academy of SciencesMoscow 117993Russia Physics Department Saint Petersburg State UniversitySt.Petersburg 199034Russia

Memrist.rs are promising candidates for synapse emulation in brain-inspired neuromorphic computing *** main obst.cle to their usage in such syst.ms is high variability of memrist.ve characterist.cs and its severe negative effect on the neural network *** paper addresses the issue from two points of view on the example of the parylene-based memrist.rs:(i)the methods of the memrist.r internal st.chast.city decrease and(ii)the methods of the memrist.ve neural network architecture *** introduction of an optimal Ag nanoparticle concentration(3 vol.%–6 vol.%)to the memrist.ve st.ucture leads to a st.tist.cally significant decrease in the switching voltage variation and endurance ***,it is shown that post.fabrication annealing improves memrist.ve characterist.cs,e.g.,resist.ve switching window increases by an order of magnitude and exceeds 106,the switching voltage variation decreases by a factor of 2(down to 7%for the set and 17%for the reset voltage),and thermost.bility is *** transmission electron microscopy and impedance spectroscopy analysis allowed est.blishing a multifilamentary resist.ve switching mechanism for nanocomposite parylene-based *** simulation of the formal neural network based on these memrist.rs demonst.ates high classification accuracy with low variation for an important biomedical task,heart disease prediction,after careful feature selection and network architecture *** prospects of the controlled incorporation of the nanocomposite parylene-based memrist.rs in neural networks are brightened by their scaling possibility in crossbar geometry.

关键词： memrist.r resist.ve switching neuromorphic computing parylene nanocomposite

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Evaluation of the Earth＇s Magnetospheric Magnetic Field Models by Means of Cosmic Ray Data

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Journal of Physical Science and Application 2012年第6期2卷 175-185页

作者： Marta I. Tyast. Olga A. Danilova Natalia G. Ptitsyna Valery E. Sdobnov st. petersburg Filial of lnst.tute of Terrest.ial Magnetism Ionosphere and Radiowave Propagation Russian Academy of Science(SPbF IZMIRAN) St. Petersburg 191023 Russia institute of Solar-Terrest.ial Physics Irkutsk 333101 Russia

At present, there are no reliable methods to evaluate uncertainty of model representation of magnetic field （MF） in the whole volume of the Earth＇s magnetosphere. Cosmic ray intensity dist.ibution on the Earth surface contains information on the space dist.ibution of magnetospheric MF through which charged particles propagate. Feasibility and limitations of cosmic ray data to be a tool for the validation of magnetospheric MF models have been analyzed. The authors＇ approach is based on the fact that time variations of magnetospheric cosmic ray are related to the changes in geomagnetic cutoff rigidities. The obtained cutoff rigidity changes by the trajectory tracing method in the MF model with those obtained on the base of experimental cosmic ray data have also been compared. The obtained results have shown that cosmic ray data can be successfully used for validation of models in presenting the dynamic st.ucture of magnetospheric MF at mid latitudes.

关键词： Magnetospheric model cosmic rays geomagnetic cutoff rigidity.

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Frontiers of physics 2016年第5期11卷 57-78页

作者： V. R. Shaginyan A. Z. Msezane G. S. Japaridze K. G. Popov V. A. Khodel petersburg Nuclear Physics institute NRC Kurchatov Institute Gatchina 188300 Russia Clark Atlanta University Atlanta GA 30314 USA Komi Science Center Ural Division RAS Syktyvkar 167982 Russia Russian Research Centre Kurchatov institute Moscow 123182 Russia McDonnell Center for the Space Sciences & Department of Physics Washington University St. Louisa MO 63130 USA

The aim of this review paper is to expose a new st.te of matter exhibited by st.ongly correlated Fermi syst.ms represented by various heavy-fermion （HF） metals, two-dimensional liquids like 3He, compounds with quantum spin liquids, quasicryst.ls, and syst.ms with one-dimensional quantum spin liquid. We name these various syst.ms HF compounds, since they exhibit the behavior typical of HF metals. In HF compounds at zero temperature the unique phase transition, dubbed throughout as the fermion condensation quantum phase transition （FCQPT） can occur; this FCQPT creates flat bands which in turn lead to the specific st.te, known as the fermion condensate. Unlimited increase of the effective mass of quasiparticles signifies FCQPT; these quasiparticles determine the thermodynamic, transport and relaxation properties of HF compounds. Our discussion of numerous salient experimen- tal data within the framework of FCQPT resolves the myst.ry of the new st.te of matter. Thus, FCQPT and the fermion condensation can be considered as the universal reason for the non-Fermi liquid behavior observed in various HF compounds. We show analytically and using arguments based completely on the experimental grounds that these syst.ms exhibit universal scaling behavior of their thermodynamic, transport and relaxation properties. Therefore, the quantum physics of different HF compounds is universal, and emerges regardless of the microscopic st.ucture of the compounds. This uniform behavior allows us to view it as the main characterist.c of a new st.te of matter exhibited by HF compounds.

关键词： quantum phase transition flat bands syst.ms quantum spin liquids heavy fermions effects scaling behavior new st.te of matter non-Fermi-liquid st.tes st.ongly correlated electron quasicryst.ls thermoelectric and thermomagnetic

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Subst.tuted diamides of dipicolinic acid as extractants and ionophores for rare earth metals

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Journal of Rare Earths 2023年第8期41卷 1234-1241,I0005页

作者： Yingchao Ren Valery A.Polukeev Ekaterina V.Kenf Liudmila I.Tkachenko Mikhail Yu Alyapyshev Vasily A.Babain Andrey V.Nechaev Andrey V.Legin Dmitry O.Kirsanov institute of Chemist.y Saint-Petersburg UniversityPeterhofUniversitetsky Prospect 26198504Saint-PetersburgRussia JSVC Vekton Ul.2-oy Luch 9192019Saint-PetersburgRussia Khlopin Radium institute 194021282nd Murinsky avRussia ThreeArc Mining LLC Pr.Narodnogo Opolchenia 10198216Saint-PetersburgRussia Rusredmet Vosstanovleniya str.15bl.3198320St.PeterburgKrasnoe seloRussia

The variety of newly synthesized diamides of dipicolinic acid(DPA)bearing methyl-and oxymethyl subst.tuents in various positions of phenyl ring was invest.gated as potential ligands for liquid-liquid extraction of rare earth metal ions and as membrane active compounds in plast.cized polymeric membranes of potentiometric *** is found that scandium is extracted with 2,6-pyridinedicarboxylic acid diamides similarly to heavy lanthanides,while yttrium is extracted together with light group *** shows high selectivity for the separation of cadmium/zinc,lead/nickel or copper/nickel *** four out of six st.died ligands demonst.ate significant potentiometric sensitivity towards scandium,yttrium and lanthanides in 10^(-7)-10^(-3)mol/L concentration range in nitric acid *** trends in sensitivity values vary depending on a ligand st.ucture and the highest.values are observed for Sc^(3+)and heavy *** to the evaluated selectivity Sm^(3+)is the most.preferred ion,while La^(3+)is the most.*** differences in sensor behavior in rare earth metal solutions assume that such devices can be applied in sensor arrays for potentiometric analysis of lanthanide mixtures.

关键词： Dipicolini cacid diamides Scandium Yttrium Lanthanides Extraction Potentiometric sensors

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Effect of interface carbonization on dielectric properties of potassium nitrate nanocomposite based on porous glasses

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Journal of Advanced Dielectrics 2022年第4期12卷 42-48页

作者： A.Molokov A.Sysoeva A.Naberezhnov R.Kumar E.Koroleva S.Vakhrushev Peter the Great st.-petersburg Polytechnical University Polytechnicheskaya 29195251 St.-PetersburgRussia Ioffe institute Polytekhnicheskaya 26194021 St.-PetersburgRussia Laboratory for High Performance Ceramics Department of Metallurgical and Materials Engineering Indian Institute of Technology-Madras(IIT Madras)Chennai 600036India

Dielectric properties and st.ucture of pure and carbon-modified nanocomposites on the base of porous glasses with an average pore diameter of 6 nm(PG6)with embedded KNO3 have been st.died at the temperature diapason of 300-430 K and at fre-quencies of 0.1-3×10^(6) Hz on cooling.X-ray diffraction st.dies of these samples have shown,that in modified and unmodified composites there is a mixture of the low-temperature paraelectric phase(α-phase)and the ferroelectricγ-*** modified composites,a decrease in permittivity and conductivity is *** response has been analyzed in the framework of modern theoretical *** relaxation processes have been identified and their origin has been *** has been found that the main contribution to the dielectric response of nanocomposite material PG6+KNO3 is provided by charge polarization on interfaces,which can be governed by modifying the inner pore ***-conductivity of both composites has been est.mated and the activation energies have been *** energy change observed in a vicinity of 360 K is attributed to the phase transformation and the appearance of KNO3α-phase.

关键词： Nanocomposites ferroelectrics potassium nitrate porous glasses dielectric properties

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Pellet Injectors Developed at the Pelin Laboratory for st.ady-st.te Plasma Fuelling

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Plasma Science and Technology 2004年第3期6卷 2286-2290页

作者： I.Vinyar A.Geraud H.Yamada R.Sakamoto Y.Oda A.Lukin A.Umov S.Skoblikov G.Gros G.Saksaganskii P.Reznichenko I.Krasilnikov V.Panchenko PELIN Laboratory Ltd. 2 Admiral Makarov St. Moscow 125212 Russia Association Euratom-CEA Departement de Recherches sur la Fusion Controllee CEA/Cadarache 13108 St Paul Lez Durance France National institute for Fusion Science 322-6 Oroshi-cho Toki-shi 509-5292 Japan Mitsubishi Heavy Indust.ies Ltd. 1-1 Wadasaki-cho 1-Chome Hyogo-ku Kobe-shi 652-8585 Japan D. V. Efremov Scientific Research institute of Electrophysical Apparatus St. Petersburg 196641 Russia

Pneumatic and centrifugal injectors for st.ady-st.te plasma refuelling bysolid hydrogen, deuterium and tritium pellets have been designed at the PELIN Laboratory to meetrequirements of LHD, TORE SUPRA, and ITER. Prese... 详细信息

关键词： pellet plasma fuelling

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Wearable Robots for Human Underwater Movement Ability Enhancement:A Survey

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IEEE/CAA Journal of Automatica Sinica 2022年第6期9卷 967-977页

作者： Haisheng Xia Muhammad Alamgeer Khan Zhijun Li MengChu Zhou IEEE Department of Automation University of Science and Technology of ChinaHefei 230026China institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230026China Helen and John C.Hartmann Department of Electrical and Computer Engineering New Jersey Institute of TechnologyNewark NJ 07102 USA Department of Cyber-Physical Syst.ms St.Petersburg State Marine Technical UniversitySt.Petersburg 198262Russia

Underwater robot technology has shown impressive results in applications such as underwater resource *** underwater applications that require extremely high flexibility,robots cannot replace skills that require human dexterity yet,and thus humans are often required to directly perform most.underwater *** robots(exoskeletons)have shown outst.nding results in enhancing human movement on *** are expected to have great potential to enhance human underwater *** purpose of this survey is to analyze the st.te-of-the-art of underwater exoskeletons for human enhancement,and the applications focused on movement assist.nce while excluding underwater robotic devices that help to keep the temperature and pressure in the range that people can *** work discusses the challenges of exist.ng exoskeletons for human underwater movement assist.nce,which mainly includes human underwater motion intention perception,underwater exoskeleton modeling and human-cooperative *** research should focus on developing novel wearable robotic st.uctures for underwater motion assist.nce,exploiting advanced sensors and fusion algorithms for human underwater motion intention perception,building up a dynamic model of underwater exoskeletons and exploring human-in-theloop control for them.

关键词： Cyborg intelligence diving exoskeleton intention perception modeling and control swimming underwater exoskeletons underwater robots wearable robots

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