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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1583-1612页

作者： Sergiy Reutskiy Yuhui Zhang Jun Lu Ciren Pubu A.Pidhornyi Institute of Mechanical Engineering Problems of nas of ukraine Kharkiv61046Ukraine College of Mechanics and Materials Hohai UniversityNanjing211100China Nanjing Hydraulic Research Institute Nanjing210029China Shigatse Everest Urban Investment and Development Group Co Ltd.857000China

This paper presents an efficient numerical technique for solving multi-term linear systems of fractional ordinary differential equations(FODEs)which have been widely used in modeling various phenomena in engineering and *** approximate solution of the system is sought in the formof the finite series over the Müntz *** using the collocation procedure in the time interval,one gets the linear algebraic system for the coefficient of the expansion which can be easily solved numerically by a standard *** technique also serves as the basis for solving the time-fractional partial differential equations(PDEs).The modified radial basis functions are used for spatial approximation of the *** collocation in the solution domain transforms the equation into a system of fractional ordinary differential equations similar to the one mentioned *** examples have verified the performance of the proposed novel technique with high accuracy and efficiency.

关键词： System of FODEs numerical solution Müntz polynomial basis time fractional PDE BSM collocation method

Hybrid bimetallic cluster ZrO2/Rh@N,S co-doped porous carbon nanosheets for efficient hydrogen evolution in acid electrolytes

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Tungsten 2024年第4期6卷 657-662页

作者： Xin-Yi Zhang Igor V.Zatovsky Jun-Ming Cao Xing-Long Wu Faculty of Chemistry Northeast Normal University F.D.Ovcharenko Institute of Biocolloidal Chemistry NAS Ukraine MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal University

Acid hydrogen evolution reaction (HER) is a critical energy conversion process,which is significantly important in hydrogen energy manufacturing and storage [1].Although the performance of noble metal platinum (Pt)-based catalysts in acidic HER is well known,the challenges are high cost,limited reserves,poor stability,and susceptibility to toxic substances [2].Therefore,it is urgent to design and manufacture acidic HER catalysts with high reactivity,high stability,and low cost.

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Synergistic Co-doping effect of CNTs and PVP in Na_(4)MnCr(PO_(4))3 cathode as a strategy for improving the electrochemical performance of SIBs

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Chinese Chemical Letters 2024年第2期35卷 539-543页

作者： Ruoyu Chen Denys S.Butenko Shilin Li Xinyu Zhang Guangshe Li Igor V.Zatovsky Wei Han College of Physics State Key Laboratory of Inorganic Synthesis and Preparative ChemistryInternational Center of Future ScienceJilin UniversityChangchun 130012China Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China F.D.Ovcharenko Institute of Biocolloidal Chemistry NAS UkraineKyiv 03142Ukraine

In order to solve the contradiction between the rapidly growing energy demand and the excessive exploitation of fossil fuels,it is urgent to research and develops more environmentally friendly and efficient energy storage ***,the development of high-performance cathode materials to enhance the energy density of SIB is currently one of the most important topics of scientific *** high-voltage and low-cost cathode material for SIBs,a composite of carbon-coated Na_(4)MnCr(PO_(4))_(3)(nasICON-type),polyvinylpyrrolidone(PVP),and modified carbon nanotubes(CNTs)is prepared by sol-gel and freeze-drying *** to the high conductivity of CNTs,the conductivity of the composite is significantly improved,and its initial capacity is increased to 114 mAh/g at 0.5 C and 96 mAh/g at 5 C(Mn^(2+)/Mn^(4+)conversion for voltage windows 1.4-4.3 V).Moreover,the multi-electrons transfer of Cr^(3+)/Cr^(4+) and Mn^(2+)/Mn^(4+) can provide a high capacity of 165 mAh/g at 0.1 C and 102 mAh/g at 5 C in the high voltage window of 1.4-4.6 ***,PVP can effectively inhibit the Jahn-Teller effect caused by Mn ion,making the composite have more excellent high-rate performance and *** addition,GITT,EIS and CV curves were drawn to better reveal the excellent kinetic properties of Na_(4)MnCr(PO_(4))_(3)@C@PVP@CNT cathode,and the mechanism of its performance improvement is deeply studied and ***,the co-doping of CNTs and PVP is a simple way to high conductivity and fast charging of cathode materials for SIBs.

关键词： Sodium-ion batteries Na_(4)MnCr(PO_(4))_(3) Carbon nanotubes Polyvinylpyrrolidone Synergistic effect

The role of singlet oxygen and hydroxyl radical in the photobleaching of meso-substituted cationic pyridyl porphyrins in the presence of folic acid

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JOURNAL OF INNOVATIVE OPTICAL HEALTH SCIENCES 2024年第5期17卷 67-80页

作者： Mkrtchyan, Lusine Seferyan, Torgom Parkhats, Marina Lepeshkevich, Sergei Dzhagarov, Boris Shmavonyan, Gagik Tuchina, Elena Tuchin, Valery Gyulkhandanyan, Grigor nas Armenia Inst Biochem Lab Bioengn 5-1 Paruyr Sevak St Yerevan 0014 Armenia nas Armenia Inst Biochem Lab Biomed Res 5-1 Paruyr Sevak St Yerevan 0014 Armenia nas Belarus BI Stepanov Inst Phys 68-2 Nezavisimosti Ave Minsk 220072 BELARUS Natl Polytech Univ Armenia 105 Teryan St Yerevan 0009 Armenia Saratov NG Chernyshevskii State Univ Sci Med Ctr 83 Astrakhanskaya St Saratov 410012 Russia

Using a photosensitizer (PS), light, and oxygen, photodynamic therapy creates cytotoxic reactive oxygen species, such as singlet oxygen (1O2), that kill cancer cells. Many cancer cell lines have up to 300 times more folic acid receptors than healthy cells. Therefore, folic acid is often used to improve selectivity of PSs. Photobleaching poses a disadvantage for PSs. In this paper, we have studied the photoinduced changes of meso-substituted cationic pyridyl porphyrins in the presence of folic acid using fluorescence and absorption spectroscopy. In this work, it was demonstrated that L-histidine, which is a 1O2 quencher, and D-mannitol, which is a hydroxyl radical quencher, can reduce photobleaching of cationic porphyrins and their interaction products with FA. This implies both singlet oxygen and hydroxyl radicals are involved in photobleaching. Additionally, our study revealed certain important features of the photobleaching of cationic porphyrins in the presence of folic acid.

关键词： Photodynamic therapy cancer quenchers histidine mannitol PHOTODYNAMIC THERAPY GLYCEROL (1)DELTA(G) HEMOGLOBIN MANNITOL DNA

Investigation of WZ Sge-type Dwarf Nova ASASSN-19oc:Optical Spectroscopy and Multicolor Light Curve Analysis

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Research in Astronomy and Astrophysics 2024年第8期24卷 20-31页

作者： Viktoriia Krushevska Sergey Shugarov Paolo Ochner Yuliana Kuznyetsova Mykola Petrov Peter Kroll Astronomical Institute of the Slovak Academy of Sciences Tatranska Lomnica05960 VysokéTatrySlovakia Main Astronomical Observatory of nas of ukraine 27 Akademika Zabolotnoho St.03143 KyivUkraine INAF—Osservatorio Astronomico di Padova Vicolo dell’Osservatorio 5I-35122 PadovaItaly Department of Physics and Astronomy University of PadovaVia F.Marzolo 8I-35131 PadovaItaly Max Planck Computing and Data Facility(MPCDF) Gießenbachstrasse 2D-85748 GarchingGermany Sonneberg Observatory Sternwartestr.32D-96515 SonnebergGermany

In this study,we present an investigation of the newly discovered dwarf nova ASASSN-19oc during its superoutburst on 2019 June *** carried out detailed UBVRcIc-photometric observations and also obtained a spectrum on day 7 of the outburst,which shows the presence of hydrogen absorption lines commonly found in dwarf nova *** of photometric data reveals the occurrence of early superhumps in the initial days of observations,followed by ordinary and late *** have accurately calculated the period of the ordinary superhumps as Pord=0.05681(10)days and determined the periods at different stages,as well as the rate of change of the superhump period(P_(dot)=(5)P/P=8.1×10^(-5)).Additionally,we have derived the mass ratio of the components(q=0.09),and estimated the color temperature during the outburst as~11,000 K,the distance to the system(d=560 pc)and absolute magnitude of the system in outburst(MV=5.3).We have shown that outbursts of this star are very rare:based on brightness measurements on 600 archival photographic plates,we found only one outburst that occurred in *** fact,as well as the properties listed above,convincingly shows that the variable ASASSN-19oc is a dwarf nova of WZ Sge type.

关键词： (stars)binaries(including multiple) close-(stars)novae-cataclysmic variables-stars dwarf novae

Cretaceous crown male ant reveals the rise of modern lineages

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ZOOLOGICAL RESEARCH 2024年第5期45卷 983-989页

作者： Wu, Qiong Radchenko, Alexander G. Engel, Michael S. Li, Xiao-Qin Yang, Hong-Ru Li, Xing-Ru Shih, Chung-Kun Ren, Dong Gao, Tai-Ping Capital Normal Univ Coll Life Sci Beijing 100048 Peoples R China Smithsonian Inst Dept Paleobiol Natl Museum Nat Hist Washington DC 20013 USA nas ukraine I I Schmalhausen Inst Zool UA-01054 Kiev Ukraine Amer Museum Nat Hist Div Invertebrate Zool New York NY 10024 USA Univ Nacl Mayor San Marcos Fac Ciencias Biol Lima 110058 Peru Univ Nacl Mayor San Marcos Dept Entomol Museo Hist Nat Peru Codigo postal Lima 14 Peru Capital Normal Univ Analyt & Testing Ctr Dept Chem Beijing 100048 Peoples R China

Most described Mesozoic ants belong to stem groups that existed only during the Cretaceous period. Previously, the earliest known crown ants were dated to the Turonian (Late Cretaceous, ca. 94-90 million years ago (Ma)) deposits found in the USA, Kazakhstan, and Botswana. However, the recent discovery of an alate male ant in Kachin amber from the earliest Cenomanian (ca. 99 Ma), representing a new genus and species, Antiquiformica alata, , revises the narrative on ant diversification. Antiquiformica can be distinctly differentiated from all known male stem ants by its geniculate antennae with elongated scape, extending far beyond the occipital margin of the head and half the length of the funiculus, as well as its partly reduced forewing venation. Furthermore, the combination of a one-segmented waist with a well- developed node, elongated scape extending beyond the occipital margin, and reduced forewing venation, particularly the completely reduced m-cu and rs-m crossveins and absence of rm and mcu closed cells, firmly places the fossil within the extant subfamily Formicinae. Fourier transform infrared spectroscopy (FTIR) confirmed that the amber containing Antiquiformica alata originated from the Kachin mines in Myanmar. This discovery significantly revises our understanding of the early evolution of Formicinae. The presence of Antiquiformica in Cenomanian amber indicates that the subfamily Formicinae emerged at least by the start of the Late Cretaceous, with crown ants likely originating earlier during the earliest Cretaceous or possibly the Late Jurassic, although paleontological evidence is lacking to support the latter hypothesis.

关键词： Formicidae Formicinae Morphology Taxonomy Antiquiformica alata Paleontology Kachin amber HYMENOPTERA-FORMICIDAE INFRARED-SPECTROSCOPY AMBER HYMENOPTERA EARLY EVOLUTION FOSSIL ANTS DIVERSIFICATION GENERA DOLICHODERINAE COLOBOPSIS PHYLOGENY

Monitoring of ground subsidence movements over territory of mines being flooded in Budyonnovsky and Proletarsky districts in Donetsk city with help of GPS-technology

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中国有色金属学会会刊：英文版 2005年第S1期15卷 266-268页

作者： A.V. Antsiferov Y.N. Gavrilenko N.N. Kiselyov UkrNIMI nas ukraine Donetsk 83121 UkraineDonetsk National Technical University Donetsk 83000 UkraineUkrNIMI NAS Ukraine Donetsk 83121 Ukraine

This paper considers the processes of activation in ground subsidence movements in flooding mine workings of mines being liquidated in two districts in Donetsk city on the area of more than 60km^2. A concept is given to build up control network of geomechanical monitoring in conditions of existing old mining operations at shallow depths (down to 100m), strong damages of objects of urban building. Given are GPS network structure, layouts for location of basic and local profile lines, special control stations for monitoring ground subsidence movements over the territory of mines being flooded. Results of the series of observations made are discussed and their accuracy is analyzed.

关键词： ground surface movement activation GPS network geomechanical monitoring mine

Low-agglomerated yttria nanopowders via decomposition of sulfate-doped precursor with transient morphology

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Journal of Rare Earths 2014年第4期32卷 320-325页

作者： R.P.Yavetskiy D.Yu.Kosyanov V.N.Baumer A.G.Doroshenko A.I.Fedorov N.A.Matveevskaya A.V.Tolmachev O.M.Vovk Institute for Single Crystals of nas of ukraine State Scientific Institution"Institute for Single Crystals"of nas of ukraine

The fabrication peculiarities of low-agglomerated yttria （Y2O3） nanopowders via thermal decomposition of sulfate-doped precursor with transient morphology were studied. It was determined that Y2（OH）5（NO3）x（CO2）y（SO4）z·nH2O （n=1-2） crystalline precursor underwent fragmentation and decomposition into isolated quasi-spherical Y2O3 particles upon calcination. Effect was con-nected with minimizing the free energy of the plate-like crystallites via reducing the contact surface until to the moment of spheroidi-zation and attainment of isolation that occurred atТ=1100 °С. Residual sulfate ions slowed down the surface diffusion during heat treatment thus retaining quasy-spherical morphology and low aggregation degree of Y2O3 nanopowders. Sulfate-doped yttria nanopowders with medium particle size of 53±13 nm possessed improved sinterability in comparison with undoped ones arising from finer particle size, narrower particle distribution and lower agglomeration degree.

关键词： precursor transient morphology sulfate-ions yttria nanopowders particle size sinterability rare earths

Selective catalytic reduction of NOX with ethanol and other C1-4 oxygenates over Ag/Al2O3 catalysts: A review

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Frontiers of Chemical Science and Engineering 2020年第4期14卷 471-491页

作者： Pavlo I.Kyriienko L.V.Pisarzhevskii Institute of Physical Chemistry of the nas of ukraine Kyiv 03028Ukraine

Research results regarding selective catalytic reduction(SCR)of NOx with ethanol and other C1-4 oxygenates as reductants over silver-alumina catalysts are *** aspects of the process mechanism,nature of active sites,role of alumina and silver(especially in the formation of bifunctional active sites),effects of reductants and reaction conditions are *** has been determined that key stages of the process include formation of reactive enolic species,their interaction with NOx and formation of nitroorganic compounds which transform to NCOads species and further to *** results obtained over various silver-alumina catalysts demonstrate the perspectives of their application for reducing the level of nitrogen oxides in engine emissions,including in the presence of water vapor and sulfur *** to improve the catalysts for the SCR of NOx with C1-4 oxygenates are outined.

关键词： SCR nitrogen oxides silver-alumina catalyst silver species ethanol oxygenates

Determining the Source Time Function Using the Modified Matrix Method

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Journal of Earth Science 2016年第6期27卷 1054-1059页

作者： Anastasiia Pavlova Carpatian Branch of Subbotin Institute of Geophysics of NAS of Ukraine Lviv 79060 Ukraine

The modified matrix method of construction of wavefield on the free surface of an anisotropic medium is proposed. The earthquake source represented by a randomly oriented force or a seismic moment tensor is placed on an arbitrary boundary of a layered anisotropic medium. The theory of the matrix propagator in a homogeneous anisotropic medium by introducing a ＂wave propagator＂ is presented. It is shown that the matrix propagator can be represented by a ＂wave propagator＂ in each layer for anisotropic layered medium. The matrix propagator P（z, z0=0） acts on the free surface of the layered medium and generates stress-displacement vector at depth z. The displacement field on the free surface of an anisotropic medium is obtained from the received system of equations considering the radiation condition and that the free surface is stressless. The new method determining source time function in anisotropic medium for three different types of seismic source is validated.

关键词： matrix method seismic tensor synthetic seismograms.