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Particuology 2014年第6期12卷 22-28页

作者： E.V.Tretyachenko A.V.Gorokhovsky G.Y.Yurkov f.s.fedorov M.A.Vikulova D.s.Kovaleva E.E.Orozaliev Department of Chemistry Saratov State Technical University

TiO2 compounds possess relatively high adsorption abilities and exhibit high photocatalytic activities that exhibit potential for the destruction of organic pollutants in natural and waste *** potassium polytitanates modified using transition metals and their oxides/hydroxides generate new nanomaterials that operate in the visible spectral *** study presents the synthesis and investigation of the structure,composition and photocatalytic activity of powdered nanoscale quasi-amorphous potassium polytitanates particles modified with iron,zinc,copper,cobalt and nickel sulfate in aqueous *** of the powders investigated in this work exhibit a high adsorption capacity for methylene blue dye（15-20mg/g） related to the welldeveloped surface of the layered potassium polytitanate *** transition metals and their oxides/hydroxides influences the electronic structure of the obtained systems.A high photocatalytic activity was observed for systems containing iron,zinc,nickel and their oxides/hydroxides in the ultraviolet and visible ranges.

关键词： Layered potassium titanate Chemical modification Heterostructured particles Photocatalytic activity Adsorption

selection of shaped charges parameters for producing aluminum particles with velocities in the range of 2.5-16 km/s

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Defence Technology（防务技术） 2024年第8期38卷 126-135页

作者： Vladimir I.Kolpakov sergey V.fedorov Ekaterina P.Vinogradova Irina A.Bolotina Bauman Moscow state Technical University Moscow 105005Russia

Testing rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out using shaped charges. To substantiate the design parameters of shaped charges that ensure the formation of aluminum particles in a wide velocity range(from 2.5 to 16 km/s), numerical modeling of the formation process was carried out within the framework of a two-dimensional axisymmetric problem of continuum mechanics using three different computing codes to increase the reliability of the results. The calculations consider shaped charges with a diameter of 20-100 mm with aluminum liners of various shapes. It is shown that the formation of particles with velocities close to the lower limit of the considered range is ensured by gently sloping segmental liners of degressive thickness. To form higher-velocity particles with velocities over 5 km/s, it is proposed to use combined liners, the jet-forming part of which has the shape of a hemisphere of constant thickness or the shape of a semi-ellipsoid or semi-superellipsoid of rotation of degressive thickness.

关键词： space debris Meteoric impact Explosion shaped charge High-velocity aluminum element segmental liner Combined liner Numerical simulation

Change in Grain-size Composition of Lignite under Cyclic freezing-Thawing and Wetting-Drying

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Natural Resources 2024年第1期15卷 17-27页

作者： Natalia s. Batugina Vladislav I. fedorov Chersky Institute of Mining of the North siberian Branch Russian Academy of sciences Yakutsk Russia

The paper presents the change in grain-size composition of lignite under cyclic freezing-thawing (fTC) and wetting-drying (WDC). The article shows that in the spring and autumn periods the lignites can be subjected to repeated freezing-thawing and wetting-drying, which determines the possibility of changing their grain-size composition and structure. Experimental studies in laboratory conditions on the influence of cyclic freezing-thawing (fTC) and wetting-drying (WDC) on the quality indicators of lignites have been carried out, their granulometric (fractional) composition has been studied. freezing-thawing cycle conditions are as follows (fTC): minimum exposure temperature: -20°C;maximum: +5°C;relative humidity: 30%;number of processing cycles: 3. Wetting-drying cycles are as follows (WDC): drying temperatures are +20, +40, +60, +80°C, drying time 90 minutes, the coals are further subjected to rain (soaking) for a period of water saturation to humidity of 30% - 40% and dry again. The number of wetting-drying cycles is 3 times. The tests have revealed the destructive effects of fTC and WDC on the samples of lower metamorphic grade coal, and the cycles of wet-dry lead to the much higher yield of fine sizes (-6+0;-13+0 mm) than the cycles of freeze-thaw. furthermore, it is found that the increase in the yield of fines depends on the heating temperature: coal disintegration proceeds more intensively at a higher temperature of drying.

关键词： Lignite freezing-Thawing Cycle Wetting-Drying Cycle Grain size Composition Dust Coal storage Loss Quality

Measurement of yields and angular distributions ofγ-quanta from the interaction of 14.1 MeV neutrons with oxygen,phosphorus,and sulfur

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Chinese Physics C 2024年第3期48卷 79-92页

作者： D.N.Grozdanov N.A.fedorov s.B.Dabylova Yu.N.Kopatch I.N.Ruskov V.R.skoy T.Yu.Tretyakova C.Hramco P.I.Kharlamov G.V.Pampushik P.G.filonchik A.V.Andreev Joint Institute for Nuclear Research(JINR) DubnaRussia Institute for Nuclear Research and Nuclear Energy Bulgarian Academy of SciencesSofiaBulgaria faculty of Physics Lomonosov Moscow State UniversityMoscowRussia L.N.Gumilyov Eurasian National University AstanaKazakhstan skobeltsyn Institute of Nuclear Physics Moscow State UniversityMoscowRussia Institute of Chemistry of Moldova ChisinauRepublic of Moldova Moscow Institute of Physics and Technology MoscowRussia

A study of the inelastic scattering of neutrons with an energy of 14.1 MeV on the nuclei of oxygen,phosphorus,and sulfur was performed at the TANGRA facility at JINR(Dubna).The experiment aimed to refine existing data and obtain new data on the yields and angular distributions ofγ-quanta emitted by the studied nuclei due to neutron-induced nuclear reactions using the tagged neutron *** types of detector systems were used to registerγ-***γ-ray yields were measured using a high-purity germanium(HPGe)*** angular distributions ofγ-rays were obtained using a system of 18 scintillation detectors based on bismuth germanite Bi_(4)Ge_(3)O_(12)(BGO)located around the *** performed experiments measured the yields of two transitions for the reaction of tagged neutrons with 16O,nine transitions for the reaction with ^(31)P,and nine transitions for the reaction with ^(32)s for the first *** angular anisotropy of theγ-radiation accompanying the inelastic scattering of neutrons with an energy of 14.1 MeV on ^(31)P nuclei was also measured for the first time.

关键词： tagged neutron method yields of gamma-quanta high-resolution gamma-spectrometry neutron-nuclear reactions neutron scattering

生物炭/光催化复合材料去除水环境有机污染物研究进展

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化学试剂 2024年第5期46卷 53-62页

作者：周通任旭阳王晨阳李发站郭翔吴俊峰 fedorov svyatoslav V 华北水利水电大学环境与市政工程学院河南郑州450040 河南城建学院河南省水体污染防治与修复重点实验室河南平顶山467036 圣彼得堡国立建筑工程大学环境与市政工程学院俄罗斯圣彼得堡190005

以光催化材料为基础的高级氧化处理技术被公认为是处理水环境中有机污染物最具潜力的绿色方法之一。同时,“以废治废”逐渐成为“碳中和”背景下对污染治理的新要求,为提高环境治理水平和社会可持续发展能力,利用生物废弃物等转化为生... 详细信息

以光催化材料为基础的高级氧化处理技术被公认为是处理水环境中有机污染物最具潜力的绿色方法之一。同时,“以废治废”逐渐成为“碳中和”背景下对污染治理的新要求,为提高环境治理水平和社会可持续发展能力,利用生物废弃物等转化为生物炭已成为当前研究热点。利用生物炭具有比表面积易调控、导电性能好以及表面官能团丰富等优势,将光催化氧化与生物炭吸附进行功能协同是一种极具发展前景的有机污染物去除研究体系。概括了生物炭/光催化复合材料的制备方法与工艺,分析了复合材料中生物炭和光催化材料二者功能间的相互影响。此外,通过阐述生物炭/光催化复合材料对污染物的去除过程,深入探讨了吸附-光降解的整体作用机制,并梳理了国内外针对最新重点管控新污染物清单的相关研究进展。最后针对复合材料界面关系、电子迁移性质、综合水体应用等方面,对生物炭/光催化复合材料提出了相关讨论和未来建议。

关键词：生物炭光催化吸附-降解机制新污染物碳中和

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A route to understanding the variability in permafrost distribution under climate change

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Advances in Climate Change Research 2023年第2期14卷 164-165页

作者： Alexander N.fedorov Melnikov Permafrost Institute Yakutsk 677010Russian Federation

Researchers are concerned about the present state of permafrost,which occupies about 25%of the Earth's *** degradation disturbs the landscape and increases greenhouse gas emissions,creating serious problems for human settlements,infrastructure,new land creation and mineral resource *** in previously stable permafrost systems impact surface hydrology,transform ecosystems,and change the way people live in permafrost。

关键词： landscape greenhouse Earth

Powerful terahertz waves from long-wavelength infrared laser filaments

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Light(science & Applications) 2020年第1期9卷 204-219页

作者： Vladimir Yu.fedorov stelios Tzortzakis science Program Texas A&M University at QatarP.O.Box 23874DohaQatar P.N.Lebedev Physical Institute of the Russian Academy of sciences 53 Leninskiy ProspektMoscow 119991Russia Institute of Electronic structure and Laser(IEsL) Foundation for Research and Technology-Hellas(FORTH)P.O.Box 1527Heraklion GR-71110Greece Department of Materials science and Technology University of CreteHeraklion GR-71003Greece

strong terahertz(THz)electric and magnetic transients open up new horizons in science and *** review the most promising way of achieving sub-cycle THz pulses with extreme field *** the nonlinear propagation of two-color mid-infrared and far-infrared ultrashort laser pulses,long,and thick plasma strings are produced,where strong photocurrents result in intense THz *** corresponding THz electric and magnetic field strengths can potentially reach the gigavolt per centimeter and kilotesla levels,*** intensities of these THz fields enable extreme nonlinear optics and relativistic *** offer a comprehensive review,starting from the microscopic physical processes of light-matter interactions with mid-infrared and far-infrared ultrashort laser pulses,the theoretical and numerical advances in the nonlinear propagation of these laser fields,and the most important experimental demonstrations to date.

关键词： laser extreme optics

Low temperature properties of organicinorganic Ag/p-CuPc/n-GaAs/Ag photoelectric sensor

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science China(Technological sciences) 2008年第2期51卷 153-161页

作者： Kh. s. KARIMOV I. QAZI T. A. KHAN M. I. fedorov Physical Technical Institute of Academy of sciences GIK Institute of Engineering science and Technology state Technical University

A thin organic film of p-type semiconducting copper phthalocynanine (CuPc) was deposited by vacuum evaporation on an n-type GaAs single-crystal semiconductor substrate. The fabricated Ag/p-CuPc/n-GaAs/Ag sensor was carried through an ageing process to stabilize the parameters. Voltage-current characteristics and photoelectrical response of the sensor were investigated at a wide temperature range of 82 to 350 K. Photoelectric characteristics were measured under non-modulated filament-lamp illumination. It was observed that such sensor parameters as rectification ratio,threshold voltage,junction,shunt and series resistances,open-circuit voltage and short circuit current are temperature-dependent. It was found that wide-range voltage-current characteristics of the sensor may be de-scribed similarly to that of a schottky barrier diode. Using the experimental data on voltage-current characteristics and absorbance of the CuPc films,the energy-band diagram of the p-CuPc/n-GaAs heterojunction was developed. It was shown that data obtained from simulation of an equivalent circuit of photoelectric sensor agreed with experimental results.

关键词： organic solar cell organic-inorganic heterojunction temperature dependent I-V characteristics

fluoride solid electrolytes containing rare earth elements

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Journal of Rare Earths 2008年第2期26卷 225-232页

作者： Viera Trnovcová Pavel P. fedorov Ivan furár1 Department of Physics Faculty of Materials Science and Technology Slovak University of Technology SK-91724 Trnava Slovakia Institute of General Physics Russian Academy of Sciences Moscow Russia

Relations between the structure, ionic conductivity and dielectric properties of fluoride systems of different structures containing rare earth elements were presented. superionic conductivities, by fluoride ions, of fluorite-structured （Mf2-REf3, M=Ba, Pb, RE=La-Lu, sc, Y）, orthorhombic （REf3, RE=Tb-Er, Y）, tysonite-structured （REf3-Mf2, RE=La-Nd, M=sr）, monoclinic （BaRE2fs, RE=Ho-Yb, Y） fluoride single crystals and eutectic composites （Lif-REf3, RE=La-Gd, Y） were compared. Anisotropy of electrical properties of crystals with a lower symmetry was explained by modeling optimum ionic paths. for explanation of concentration dependences of fast ionic conductivity, models of aggregation of defects into clusters were proposed. In fluorite-structured crystals, the highest ionic conductivity was found for Pbf2：7 mol% scf3 （at 500 K, σ500=0.13 s/cm）. In tysonite-structured crystals, the highest ionic conductivity was found for Laf3：3 mol% srf2 （σ500=2.4×10^-2 s/cm）. Different types of coordination polyhedrons and their different linking in orthorhombic and tysonite structure explained large differences between conductivities in both structures. Eutectic systems, prepared as directionally solidified composites, enabled to study some orthorhombic fluoride phases （Gdf3, smf3）, which cannot be prepared as single crystals. An influence of the orthorhombic-tysonite phase transition on the ionic conductivity was shown.

关键词： rare earth containing fluorides superionic conductivity defects conduction mechanisms clustering single crystals composites

Geochemistry and petrology of superpure quartzites from East sayan Mountains, Russia

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Acta Geochimica 2019年第1期38卷 22-39页

作者： A.M.fedorov V.A.Makrygina A.I.Nepomnyaschikh A.P.Zhaboedov A.V.Parshin V.f.Posokhov Yu.V.sokolnikova A.P.Vinogradov Institute of Geochemistry sB RAs Irkutsk National Research Technical University Irkutsk scientific Center sB RAs Irkutsk state University Geological Institute sB RAs

Quartzites are widespread within Earth's lithosphere, but their highly pure varieties occur quite infrequently. With the development of alternative energy sources, including solar, and with increasing demand for high-purity quartz for optics, interest has risen in highpurity silicon-bearing materials. The quartzites discovered in the southeast part of the Eastern sayan Mountains are particularly attractive for exploration in terms of their raw material quality and feasibility to be enriched. for this reason, their genesis also merits study. Available geochemical data show that chemogenic(d^(18)O>29.2%)siliceous-carbonate sediments of the Irkut formation are fairly pure(impurity elements f the impurities are easily removed carbonate components of the rock. Bedded quartzites remote from the intrusive granitoids and near-contact quartzites were recognized based on geochemical and petrographic data. Influenced by the sumsunur granitoids, the near-contact quartzites originally contained >0.9% impurities, but later, under the action of sliding slabs of ophiolite dynamothermal treatment reduced impurities to sulting in ‘‘superquartzites' '(highly pure quartzites). The presence of only minor structural impurities is due to the enrichment capacity of superquartzites to 10.1 ppm(7.2 ppm under special conditions) of 10 elements: fe, Al, Ti, Ca, Mg, Cu,Mn, Na, K, and Li.

关键词： High-purity quartz superquartzite Gravitational sliding Dynamic metamorphism Recrystallization