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The state of gold in phases of the Cu-Fe-S system:In situ X-ray absorption spectroscopy study

Geoscience Frontiers 2023年第3期14卷 103-116页

作者： Boris R.Tagirov Olga N.Filimonova Alexander L.Trigub Ilya v.vikentyev Elena v.Kovalchuk Maximilian S.Nickolsky andrey A.Shiryaev vladimir L.Reukov Dmitry A.Chareev Institute of Geology of Ore Deposits(IGEM RAS) 35Staromonetnyi per119017 MoscowRussia National Research Centre‘Kurchatov Institute’ 1Akademika Kurchatova pl123182 MoscowRussia Institute of Physical Chemistry and Electrochemistry(IPCE RAS) 31Leninsky Prospect119071 MoscowRussia Institute of Experimental Mineralogy(IEM RAS) 142432 ChernogolovkaMoscow RegionRussia

Chalcopyrite and bornite are the main Au-bearing minerals at Cu porphyry deposits,volcanogenic massive sulfide(vMS)deposits,Cu-Ni deposits of the mafic magmatic complexes,and ores of submarine sulfide *** and intermediate solid solutions with wide compositional variations(bnss and iss–high-temperature chalcopyrite,correspondingly),which can scavenge economic concentrations of Au,appear in the Cu-Fe-S system at ore-forming ***,the state of Au in bnss and iss is yet *** solve this conundrum,we synthesized samples with net chemical composition of bnss and iss,studied them by in situ X–ray absorption spectroscopy(XAS),and used the experimental data to explain the Au distribution among natural ore-forming *** sulfide samples were obtained at 495–700℃ in Au-saturated system by means of salt flux *** bnss contained1.2–1.6 log units more Au than iss:up to 18 wt.%Au in bnss vs 0.4 wt.%Au in iss at 700*** increase of temperature resulted in the sharp increase of Au concentration in both phases,1 log unit per 100℃ at f(S2)close to S_((l)) *** of Au L_(3)-edge spectra recorded at 25–675℃ revealed that at 25℃ Au exists mainly in the metallic *** t>500℃ the spectral features of Audisappear,and “chemically bound”Au *** Au form of occurrence in the iss field is interpreted as Au-bearing clusters with a stromeyerite-like(CuAgS)*** Cu_(2–x)S and bnss contain Au in a mixture of stromeyeritelike and petrovskaite-like(Au_(0.8)Ag_(1.2)S)*** chemical composition of both forms is close to CuAuS,where the nearest Au neighbors are two S atoms at R_(Au-S)=2.34–2.36Å.Results of the present study allow to determine the state of Au and its concentration in the main Cu-bearing minerals of sulfide ores as a function of the T-f(S_(2))-compositional *** to the sharp increase of the CuAuS clusters stability with increasing temperature,in high-temperature ores formed at t>350℃ A

关键词： “Invisible”gold Bornite solid solution Intermediate solid solution Digenite Chalcopyrite X-ray absorption spectroscopy

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Resolution and contrast enhancement of laser-scanning multiphoton microscopy using thulium-doped upconversion nanoparticles

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Nano Research 2019年第12期12卷 2933-2940页

作者： Alexey B.Kostyuk Artem D.vorotnov andrey v.Ivanov Arthur B.volovetskiy Aleksandr v.Kruglov Lyudmila M.Sencha Liuen Liang Evgenii L.Guryev vladimir A.vodeneev Sergey M.Deyev Yiqing Lu Andrei v.Zvyagin Lobachevsky State University of Nizhny Novgorod Nizhny Novgorod 603950Russia Center of Biomedical Engineering Institute of Molecular MedicineSechenov UniversityMoscow 119991Russia ARC Centre of Excellence"Nanoscale BioPhotonics" Department of Physics and AstronomyMacquarie UniversitySydney 2109Australia Institute ofBioorganic Chemistry Russian Academy of SciencesMoscow 117997Russia

High-contrast optical imagi ng is achievable using phosphoresce nt labels to suppress the short-lived background due to the optical backscatterand autofluoresce ***,the long-lived phosphorescence is generally incompatible with high-speed laser-scan ning imaging ***,we show that upc on versi on nan oparticles of structure NaYF4:Yb co-doped with 8%Tm(8T-UCNP)in combi nation with a commerciallaser-scanning multiphoton microscopy are uniquely suited for labeling biological systems to acquire high-resolution images with the enhancedcon *** comparison with many phosphoresce nt labels,the 8T-UCNP emission lifetime of-15μs affords rapid image ***-order optical nonlinearity of the 8T-UCNP(n=4,as confirmed experimentally and theoretically)afforded pushing the resolution limitattain able with UCNPs to the *** contrast enha nceme nt was achieved by suppressing the backgro und using(i)ban dpassspectral filtering of the narrow emission peak of 8T-UCNP at 455-nm,and(ii)time-gating implemented with a time-correlated single-photon counting system that demonstrated the contrast enhancement of>2.5-fold of polyethyle neimine-coated 8T-UCNPs take n up by huma nbreast adeno carcinoma cells *** a result,discrete 8T-UCNP nan oparticles became clearly observable in the freshly excised splee ntissue of laboratory mice 15-min post in trave nous injectio n of an 8T-UCNP *** dem on strated approach paves the way forhigh-contrast,high-resoluti on,and high-speed multiphot on microscopy in challe nging envir onments of i ntense autofluorescence,exogenous staining,and turbidity,as typically occur in intravital imaging.

关键词： upconversion nanoparticles autofluorescence time-gated imaging scanning microscopy time-correlated single photon counting

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Sociability and pair-bonding in gerbils: a comparative experimental study

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Current Zoology 2019年第4期65卷 363-373页

作者： andrey v. TCHABOvSKY Ludmila E. SAvINETSKAYA Natalia L. OvCHINNIKOvA Alexandra SAFONOvA Olga N. ILCHENKO Svetlana R. SAPOZHNIKOvA Nina A. vASILIEvA Department of vertebrate Zoology A.N. Severtsov Institute of Ecology and Evolution Moscow Russia Laboratory for Population Ecology Lomonosov Moscow State University Russia Moscow Zoo Russia

In a study of gerbils with contrasting social and mating systems (group-living monogamous Mongolian gerbil Meriones unguiculatus, solitary nonterritorial promiscuous midday jird M. meridianus, and solitary territorial promiscuous pale gerbil Gerbillus perpallidus), we employed part ner pref ere nee tests (PPTs) to assess among-species variation in sociability and pair-bonding patterns and tested whether the nature of contact between individuals: direct contact (DC) versus nondirect contact (NDC) affected our results. We measured male pref ere nces as the time: 1) spe nt alone, 2) with familiar (partner), and 3) unfamiliar (stranger) female in the 3-chambered apparatus. Gerbil species differed strongly in sociability and male partner preferences. The time spent alone was a reliable indicator of species sociability indepe ndent of the nature of con tact, whereas the pattern and level of betwee n-species differe nces in male partner preferences depended on con tact type: DC PPTs, un like NDC-tests, discriminated well betwee n monogamous and promiscuous species. In the DC-tests, stranger-directed aggression and stranger avoidanee were observed both in the highly social monogamous M. unguiculatus and the solitary territorial promiscuous G. perpallidus, but not in the non territorial promiscuous M. meridianus. In M. unguiculatus, stranger avoidanee in the DC-tests increased the time spent with the partner, thus providing evidence of a partner preference that was not found in the NDC-tests, whereas in G. perpallidus, stran ger avoidance in creased the time spe nt alone. This first comparative experimental study of partner prefere nces in gerbils provides new in sights into the in terspecific variation in gerbil sociality and mating systems and sheds light on behavioral mechanisms un derlyi ng social fidelity and pair-b on ding.

关键词： gerbils mating systems partner preference test partner fidelity social systems stranger-directed aggression

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Energy Gap in Saturn’s Rings

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Journal of Modern Physics 2019年第4期10卷 477-485页

作者： andrey Yu Pospelov vladimir v. Tchernyi Independent Researcher Los Angeles USA Modern Science Institute at SAIBR Moscow Russia

In this article, we consider, based on the super-diamagnetic model, the new problems of Saturn’s rings discovered by Cassini, such as: 1) anomalous purity of water ice;2) Saturn’s magnetic field alignment with the planet’s rotation axis;3) “ring rain” of the submicron particles;4) the deviation in the qualitative composition of the “rain” from the composition of the rings;5) “dirt” concentrated in the ring gaps;6) “plateaus” in Saturn’s C ring;7) age of the rings;8) roll-off in the spectrum of Saturn’s rings, and 9) “propellers” in Saturn’s A ring. Interpretation of Cassini’s observations of spectral roll-off in Saturn’s rings in the wavelength range from 100 micrometers to 0.5 mm is given. It was concluded that the substance of the rings could be in the superconducting state. An explanation of the Cassini spectral data is given using the hypothesis of the existence of a superconducting energy gap in the substance of rings.

关键词： Saturn Rings Cassini CIRS Interpretation Super-Diamagnetic Model Superconducting Energy Gap Ring Rain Plateaus and Propellers in Saturn’s Rings

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New luminescent 10-oxybenzoquinolate complexes of rare earth metals

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Journal of Rare Earths 2023年第8期41卷 1135-1143,I0001页

作者： Tatyana v.Balashova Svetlana K.Polyakova vasily A.Ilichev andrey A.Kukinov Roman v.Rumyantcev Georgy K.Fukin Ivan D.Grishin Artem N.Yablonskiy Alexander F.Shestakov Mikhail N.Bochkarev G.A.Razuvaev Institute of Organometallic Chemistry of Russian Academy of Sciences Tropinina Street49603950Nizhny NovgorodRussian Federation Nizhny Novgorod State University Gagarina Avenue 23/2603950Nizhny NovgorodRussian Federation Institute for Physics of Microstructures of Russian Academy of Sciences Akademicheskaya Street 7603950Nizhny NovgorodRussian Federation Institute of Problems of Chemical Physics of Russian Academy of Sciences Academician Semenov Avenue1ChernogolovkaMoscow Region142432Russian Federation

A series of Sc,Y,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Ho,Er,Tm and Yb complexes with oxybenzoquinoline ligands(BQ) was synthesized by the reactions of 10-hydroxybenzo[h]quinoline with cyclopentadienides or tris(trimethylsilyl)amides of rare earth *** structure,as well as the photo-and electroluminescent(PL,EL) properties of these complexes in solutions and solid state were *** solutions,complexes of sodium and lanthanides exhibit double peaked ligand-centered PL of enol and keto forms of BQ with a quantum yield of 1%-8%.In the solid state the complexes of Sm,Eu,Ho,Nd,Er,and Yb along with the ligand-centered PL also exhibit a moderate-intensity metal-centered PL which is characteristic of the corresponding Ln^(3+) ***(BQ)_(3) complex shows bright green EL which has intensity comparable to the best results observed for scandium complexes with other organic ligands.

关键词： Lanthanides Photoluminescence(PL) Electroluminescence(EL) 10-hydroxybenzo[h]quinoline X-ray structure Organic light-emitting diodes(OLEDs)

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Emerging 2D magnetic states in a graphene-based monolayer of EuC_(6)

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Nano Research 2022年第1期15卷 408-413页

作者： Ivan S.Sokolov Dmitry v.Averyanov Fabrice Wilhelm Andrei Rogalev Oleg E.Parfenov Alexander N.Taldenkov Igor A.Karateev andrey M.Tokmachev vyacheslav G.Storchak National Research Center“Kurchatov Institute” Kurchatov Sq.1Moscow 123182Russia ESRF-The European Synchrotron CS 4022038043 Grenoble Cedex 9France

Recent discoveries of intrinsic two-dimensional(2D)magnets open up vast opportunities to address fundamental problems in condensed matter physics,giving rise to applications from ultra-compact spintronics to quantum *** ever-growing material landscape of 2D magnets lacks,however,carbon-based systems,prominent in other areas of 2D *** measurements of the Eu/graphene compound-a monolayer of the EuC_(6) stoichiometry-reveal the emergence of 2D ferromagnetism but detailed studies of competing magnetic states are still ***,we employ element-selective X-ray absorption spectroscopy(XAS)and magnetic circular dichroism(XMCD)to establish the magnetic structure of monolayer *** system exhibits the anomalous Hall effect,negative magnetoresistance,and magnetization consistent with a ferromagnetic state but the saturation magnetic moment(about 2.5/%/Eu)is way too low for the half-filled f-shells of Eu^(2+)*** XAS/XMCD studies at the Eu L3 absorption edge probe the EuC6 magnetism in high fields and reveal the nature of the missing magnetic *** results are set against XMCD studies in Eu/silicene and Eu/germanene to establish monolayer EuC6 as a prominent member of the family of Eu-based 2D magnets combining the celebrated graphene properties with a strong magnetism of europium.

关键词： two-dimensional(2D)ferromagnetism graphene EuC_(6) X-ray magnetic circular dichroism(XMCD) monolayer

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Boron nitride nanotube growth via boron oxide assisted chemical vapor transport-deposition process using LiNO3 as a promoter

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Nano Research 2015年第6期8卷 2063-2072页

作者： Andrei T. Matveev Konstantin L. Firestein Alexander E. Steinman andrey M. Kovalskii Oleg I. Lebedev Dmitry v. Shtansky Dmitri Golberg National University of Science and Technology 'MISIS' Leninskiy prospect 4 Moscow 119049 Russia CRISMAT UMR 6508 CNRS-ENSICAEN 6BdMarechalJuin Caen 14050 France Institute for Materials Science (NIMS) Namiki 1 Ibaraki Tsukuba 3050044 Japan

High-purity straight and discrete multiwalled boron nitride nanotubes （BNNTs） were grown via a boron oxide vapor reaction with ammonia using LiNO3 as a promoter. Only a trace amount of boron oxide was detected as an impurity in the BNNTs by energy-dispersive X-ray （EDX） and Raman spectroscopies. Boron oxide vapor was generated from a mixture of B, FeO, and MgO powders heated to 1,150 ℃, and it was transported to the reaction zone by flowing ammonia. Lithium nitrate was applied to the upper side of a BN bar from a water solution. The bar was placed along a temperature gradient zone in a horizontal tubular furnace. BNNTs with average diameters of 30-50 nm were mostly observed in a temperature range of 1,280-1,320 ℃. At higher temperatures, curled polycrystalline BN fibers appeared. Above 1,320 ℃, the number of BNNTs drastically decreased, whereas the quantity and diameter of the fibers increased. The mechanism of BNNT and fiber growth is proposed and discussed.

关键词： boron nit-ride nanotubes CvD lithium nitrate lithium borate BNNT growth mechanism

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Cytotoxicity and non-specific cellular uptake of bare and surface-modified upconversion nanoparticles in human skin cells

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Nano Research 2015年第5期8卷 1546-1562页

作者： Anna E. Guller Alia N. Generalova Elena v. Petersen andrey v. Nechaev Inna A. Trusova Nikolay N. Landyshev Annemarie Nadort Ekaterina A. Grebenik Sergey M. Deyev Anatoly B. Shekhter Andrei v. Zvyagin Macquarie University Australia I.M. Sechenov First Moscow State Medical University Russia Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences Russia Nizhny Novgorod State University Russia Moscow Institute of Physics and Technology Russia Moscow State University of Fine Chemical Technologies Russia University of Amsterdam the Netherlands

The cytotoxicity and non-specific cellular uptake of the most popular composition of upconversion nanoparticle （UCNP）, NaYF4：Yb^3＋：Er^3＋, is reported using normal human skin cells, including dermal fibroblasts and immortalized human epidermal linear keratinocytes （HaCaT）. A new hydrophilization reaction of as-synthesized UCNPs based on tetramethylammonium hydroxide （TMAH） enabled evaluation of the intrinsic cytotoxicity of bare UCNPs. The cytotoxicity effects of the UCNP surface-coating and polystyrene host were investigated over the concentration range 62.5-125 μg/mL with 24-h incubation, using a MTT test and optical microscopy. The fibroblast viability was not compromised by UCNPs, whereas the viability of keratinocytes varied from 52% ± 4% to 100% ± 10% than the control group, depending on the surface modification. Bare UCNPs reduced the keratinocyte viability to 76% ± 3%, while exhibiting profound non-specific cellular uptake. Hydrophilic poly（D,L-lactide）- and poly（maleic anhydride-alt-l-octadecene）-coated UCNPs were found to be least cytotoxic among the polymer-coated UCNPs, and were readily internalized by human skin cells. Polystyrene microbeads impregnated with UCNPs remained nontoxic. Surprisingly, no correlation was found between UCNP cytotoxicity and the internalization level in cells, although the latter ranged broadly from 0.03% to 59%, benchmarked against 100% uptake level of TMAH-UCNPs.

关键词： nanoparticle upconversion surface modification biocompatibility cytotoxicity human skin

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Septic arthritis of the hand: From etiopathogenesis to surgical treatment

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World Journal of Orthopedics 2022年第11期13卷 993-1005页

作者： Konstantin v Lipatov Arthur Asatryan George Melkonyan Aleksandr D Kazantcev Ekaterina I Solov’eva Irina v Gorbacheva Alexander S vorotyntsev andrey Y Emelyanov General Surgery Department Institute of Clinical Medicine named after N.V.SklifosovskySechenov First Moscow State Medical University(Sechenov University)Moscow 119021Russia General Surgery Department State Budgetary Institution“City Clinical Hospital named after S.S.Yudin of Moscow Healthcare Department”Moscow 115142Russia General Surgery Department The Hospital for War Veterans N3Moscow 129336Russia General Surgery Department I.M.Sechenov First Moscow State Medical UniversityMoscow 119991Russia

BACKGROUND Septic arthritis of the hand,which is the second most common after damage of the knee joint,remains one of the leading causes of temporary *** inflammation can cause dysfunction of the joint,and in the most severe cases,the need for amputation of the finger may *** results of their treatment today,especially from a functional point of view,cannot be considered *** surgical treatment is extremely important in septic arthritis of the hand,as it helps to prevent cartilage destruction and the development of *** To explore the features of the course of septic arthritis of the hand as well as approaches to surgical treatment and its results,depending on the nature of the damage to the articular *** The results of the treatment of 170 patients with septic arthritis of the hand,which were treated in the period of 2020-2021,were *** of the interphalangeal and metacarpophalangeal joints(MCP)of fingers 1,2,and 3 was more often noted in 147(81.6%)*** most common cause of arthritis was a penetrating injury as a result of household trauma(101,59.4%),animal bite(30,17.6%),and clenched fist injury(15,8.8%).Septic arthritis with contiguous osteomyelitis was observed in 98(54.4%)*** treatment was completed with drainage and irrigation of the *** mobilization was used to restore *** patients with osteomyelitis,it was aimed at the formation of *** was not ***-term results of treatment were assessed in 142(83.5%)patients within 1 mo to 12 mo after discharge from the hospital[the median was 7 mo(IQR:4-9)].RESULTS The most commonly isolated organism was Staphylococcus aureus(35.3%).The median treatment delay in patients without osteomyelitis was 5 d(IQR:4-7);for septic arthritis with contiguous osteomyelitis,it was 14 d(IQR:5-21).Radiography for osteomyelitis within 2 wk was uninformative:41.2%of diagnoses.A single surgical treatment was

关键词： Septic arthritis Osteomyelitis Hand Surgical treatment Neoarthrosis

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Comparison of diode laser in soft tissue surgery using continuous wave and pulsed modes in vitro

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Frontiers of Optoelectronics 2015年第2期8卷 212-219页

作者： andrey v.BELIKOv Alexei v.SKRYPNIK Ksenia v.SHATILOvA Saint-Petersburg National Research University of Information Technologies Mechanics and Optics (ITMO University)

In this study, the interaction between diode laser radiation and chicken soft tissue was studied in vitro by a high-speed digital video camera. We used a diode laser with a wavelength of(980 ± 10) nm and average power of 10 W. The diode laser was operated in continuous wave(CW) and pulsed modes. In CW mode, the average laser radiation power was 10 W; in pulsed mode, the average laser radiation power was 10 W and the peak power was 20 W. Diode laser radiation was delivered to soft tissue(chicken meat) using a quartz optical fiber with either a clear distal end(clear tip) or a distal end containing an optothermal converter(hot tip). Application of the diode laser in pulsed mode resulted in crater depths and areas of collateral damage in soft tissue about 1.6 times greater than those observed in CW mode at treatment with the clear *** differences in the crater depth and collateral damage width of chicken meat were not found after hot-tip treatment with the diode laser in CW and pulsed *** tissue treated with the hot tip showed crater depths about 3.4 times greater than those observed after treatment with the clear tip. Hot tip treatment further resulted in collateral damage widths about 2.7 times lower than those obtained after treatment with the clear tip.

关键词： diode laser thermo-optically powered surgery hot tip surgery laser surgery soft tissue

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