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GSC 4560–02157: a new long-period eclipsing cataclysmic variable star

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Research in Astronomy and Astrophysics 2015年第7期15卷 1005-1011页

作者： Anton v.Khruslov anatoly v.Kusakin Elena A.Barsukova vitaly P.Goranskij Azamat F.valeev Nikolay N.Samus Institute of Astronomy Russian Academy of Sciences Fesenkov Astrophysical Institute Special Astrophysical Observatory Russian Academy of Sciences Sternberg Astronomical Institute Lomonosov Moscow State University

We study the newly discovered variable star GSC 4560-02157. CCD photometry was performed in 2013-2014 at the Tien Shan Astronomical Observatory,and a spectrum was obtained with the 6-m telescope of the Special Astrophysical Observatory in June, 2014. GSC 4560-02157 is demonstrated to be an eclipsing variable star（P = 0.265359d）. All its flat-bottom primary minima are approximately at the same brightness level, but the star＇s out-of-eclipse brightness and brightness at secondary minima vary considerably（by up to 0.6m） from cycle to cycle. Moreover,there are short-term（time scale of 0.03-0.04 days） small-amplitude brightness variations out of eclipse. This behavior suggests a cataclysmic nature for the star, which is confirmed with a spectrum taken on 2014 June 5. The spectrum shows numerous emissions of the hydrogen Balmer series, He Ⅰ and He Ⅱ.

关键词： stars: dwarf novae -- binaries: eclipsing -- stars: individual: GSC 4560-02157

Electrodynamics in Curvilinear Coordinates and the Equation of a Geodesic Line

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Journal of Modern Physics 2022年第11期13卷 1382-1402页

作者： anatoly v. Parfyonov Ulyanovsk State Technical University Ulyanovsk Russia

The creation of the theory of relativity, which discovered the equivalence of mass and energy, showed that the concept of a point charge, used in the formulation of Coulomb’s law, one of the basic laws of classical electrodynamics, contradicts the famous formula establishing the equivalence of mass and energy. But the discovery of quarks makes it possible to present classical electrodynamics in a form free from the indicated contradiction. In the article, having considered the electromagnetic field in a curvilinear coordinate system, a theory has been created that expands our understanding of the electromagnetic field, the nature of quarks, the nature of strong interaction, and the connection between strong interaction and electromagnetic interaction. This theory is based on the principle of equivalence of an electromagnetic field to a free material particle formulated in the article and the law of formation of elementary particles from an electromagnetic field that follows from it.

关键词： Electrodynamics Electromagnetic Field Curvilinear Coordinates Quarks Strong Interaction Equation of a Geodesic Line

Characterization and Electrochemical Properties of Nanostructured Zr-Doped Anatase TiO_2 Tubes Synthesized by Sol–Gel Template Route

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Journal of Materials Science & Technology 2017年第6期33卷 527-534页

作者： Denis P.Opra Sergey v.Gnedenkov Sergey L.Sinebryukhov Elena I.voit Alexander A.Sokolov Evgeny B.Modin anatoly B.Podgorbunsky Yury v.Sushkov veniamin v.Zheleznov Institute of Chemistry Far Eastern Branch of Russian Academy of Sciences Far Eastern Federal University National Research Centre "Kurchatov Institute"

A series of nanostructured Zr-doped anatase TiO_2 tubes with the Zr/Ti molar ratio of 0.01, 0.02, 0.03, and0.09 were prepared by a sol–gel technology on a carbon fiber template. The electrochemical performance of Zr-doped anatase TiO_2 as anodes for rechargeable lithium batteries was investigated and compared with undoped titania. Tests represented that after 35-fold charge/discharge cycling at C/10 the reversible capacity of Zr-doped titania（Zr/Ti = 0.03） reaches 135 m A h g^（-1）, while the capacity of undoped titania（Zr/Ti = 0） yielded only 50 m A h g^（-1）. Based on the results of the physicochemical investigation, three reasons of improving electrochemical performance of Zr-doped titania were suggested. According to the scanning electron microscopy and transmission electron microscopy, Zr^（4＋） doping induces a decrease in nanoparticle size, which facilitates the Li＋diffusion. The Raman investigations show the more open structure of Zr-doped TiO_2 as compared to undoped titania due to changing of the unit cell parameters, that significantly affects on the reversibility of the insertion/extraction process. The electrochemical impedance spectroscopy results indicate that substitution of Zr^（4＋） for Ti^（4＋） into anatase TiO_2 has favorable effects on the conductivity.

关键词： Li-ion batteries Anatase titania Nanostructured materials Sol–gel template process Doping Electrochemical performance

Revealing the nature of optical activity in carbon dots produced from different chiral precursor molecules

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Light(Science & Applications) 2022年第5期11卷 855-867页

作者： Ananya Das Evgeny v.Kundelev Anna A.vedernikova Sergei A.Cherevkov Denis v.Danilov Aleksandra v.Koroleva Evgeniy v.Zhizhin Anton N.Tsypkin Aleksandr P.Litvin Alexander v.Baranov anatoly v.Fedorov Elena v.Ushakova Andrey L.Rogach Center of Information Optical Technologies ITMO UniversitySaint Petersburg 197101Russia Research Park Saint Petersburg State UniversitySaint Petersburg 199034Russia Laboratory of Femtosecond Optics and Femtotechnology ITMO UniversitySaint Petersburg 197101Russia Laboratory of Quantum Processes and Measurements ITMO UniversitySaint Petersburg 197101Russia Department of Materials Science and Engineering and Centre for Functional Photonics(CFP)City University of Hong KongKowloonHong Kong SAR 999077China Shenzhen Research Institute City University of Hong KongShenzhen 518057China

Carbon dots(CDs)are light-emitting nanoparticles that show great promise for applications in biology and medicine due to the ease of fabrication,biocompatibility,and attractive optical *** chirality,on the other hand,is an intrinsic feature inherent in many objects in nature,and it can play an important role in the formation of artificial complexes based on CDs that are implemented for enantiomer recognition,site-specific bonding,*** employed a one-step hydrothermal synthesis to produce chiral CDs from the commonly used precursors citric acid and ethylenediamine together with a set of different chiral precursors,namely,L-isomers of cysteine,glutathione,phenylglycine,and *** resulting CDs consisted of O,N-doped(and also S-doped,in some cases)carbonized cores with surfaces rich in amide and hydroxyl groups;they exhibited high photoluminescence quantum yields reaching 57%,chiral optical signals in the Uv and visible spectral regions,and two-photon *** signals of CDs were rather complex and originated from a combination of the chiral precursors attached to the CD surface,hybridization of lower-energy levels of chiral chromophores formed within CDs,and intrinsic chirality of the CD *** DFT analysis,we showed how incorporation of the chiral precursors at the optical centers induced a strong response in their circular dichroism *** optical characteristics of these CDs,which can easily be dispersed in solvents of different polarities,remained stable during pH changes in the environment and after Uv exposure for more than 400 min,which opens a wide range of bio-applications.

关键词： properties chiral carbon

Directional coherent light via intensity-induced sideband emission

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Light(Science & Applications) 2016年第1期5卷 33-38页

作者： Andrew J Traverso Chris O’Brien Brett H Hokr Jonathan v Thompson Luqi Yuan Charles W Ballmann anatoly A Svidzinsky Georgi I Petrov Marlan O Scully vladislav v Yakovlev Texas A&M University College StationTX 77843USA Princeton University PrincetonNJ 08544USA Baylor University WacoTX 76798USA

We introduce a unique technique for generating directional coherent emissions that could be utilized to create coherent sources in a wide range of frequencies from the extreme ultraviolet(XUv)to the deep *** is accomplished without population inversion by pumping a two-level system with a far-detuned strong optical field that induces the splitting of the two-level system.A nonlinear process of four-wave mixing then occurs across the split system,driving coherent emission at sidebands both redand blue-detuned from the pump frequency,and propagates both forward and backward along the pump beam *** observed this phenomenon in dense rubidium vapor along both the D_(1) and D_(2) *** sideband emission exhibits a short pulse duration(o1 ns)with threshold-like behavior dependent on both the pump intensity and Rb vapor *** technique offers a new capability for manipulating the emission frequency simply through intensity-induced atomic modulation that can be scaled to most frequency regimes using various atomic/molecular ensembles and pump energies.

关键词： coherent emission collective coherence four-wave mixing

Features of adult neurogenesis and neurochemical signaling in the Cherry salmon Oncorhynchus masou brain

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Neural Regeneration Research 2013年第1期8卷 13-23页

作者： Evgeniya v. Pushchina Dmitry K. Obukhov anatoly A. varaksin Laboratory of Cytophysiology Institute of Marine Biology Far East Branch Russian Academy of Sciences St. Petersburg State University

We investigated the distribution of gamma aminobutyric acid, tyrosine hydroxylase and nitric oxide-producing elements in a cherry salmon Oncorhynchus masou brain at various stages of postnatal ontogenesis by immunohistochemical staining and histochemical staining. The periventricular region cells exhibited the morphology of neurons and glia including radial glia-like cells and contained several neurochemical substances. Heterogeneous populations of tyrosine hydroxylase-, gamma aminobutyric acid-immunoreactive, as well as nicotinamide adenine dinucleotide phosphate diaphorase-positive cells were observed in proliferating cell nuclear antigen-immunoreactive proliferative zones in periventricular area of diencephalon, central grey layer of dorsomedial tegmentum, medulla and spinal cord. Immunolocalization of Pax6 in the cherry salmon brain revealed a neuromeric construction of the brain at various stages of postnatal ontogenesis, and this was confirmed by tyrosine hydroxylase and gamma aminobutyric acid labeling.

关键词： neural regeneration neurogenesis teleostei adult neurogenesis neurotransmitter signaling migration tyrosine hydroxylase gamma aminobutyric acid development Pax6 NADPH-diaphorase proliferation grant-supported paper neuroregeneration

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

variation Trend and Characteristics of Anthropogenic CO Column Content in the Atmosphere over Beijing and Moscow

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Atmospheric and Oceanic Science Letters 2014年第3期7卷 243-247页

作者： WANG Pu-Cai Georgy S.GOLITSYN WANG Geng-Chen Evgeny I.GRECHKO vadim S.RAKITIN Ekaterina v.FOKEEvA anatoly v.DZHOLA Institute of Atmospheric Physics Chinese Academy of Sciences А.М.Оbukhov Institute of Atmospheric Physics Russian Academy of Sciences

The anthropogenic CO column content in the atmosphere is derived from measurements with infrared grating spectrometers in Beijing,China,and Moscow,Russia,during 1992–*** specific variation characteristics and long-term variation trends of the CO column content in the atmosphere in these regions are *** evident variation trend of anthropogenic CO in the atmosphere for the Beijing region is not observed during 1992–2012,while for the Moscow region,it decreases yearly by about 1.4% for the same *** CO concentrations appear quite frequently in Beijing,but much less frequently in Moscow,except during the natural fire events in summer *** back trajectory analysis,the high CO concentration observed in Beijing can be attributed to the intensive CO emission sources in its surrounding areas.

关键词： anthropogenic CO column contentinfrared grating spectrometerair pollution

俄罗斯-蒙古地学断面地壳模型的地质-地球物理资料综合研究

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地学前缘 2021年第5期28卷 260-282页

作者： Evgeny Kh.TURUTANOv Evgeny v.SKLYAROv valentina v.MORDvINOvA anatoly M.MAZUKABZOv viktor S.KANAYKIN Institute of the Earth's Crust Siberian Branch of the Russian Academy of Science Lermontov ave.128Irkutsk 664033Russia Irkutsk National Research Technical University Lermontov ave.83Irkutsk 664074Russia

地学断面是指地壳的垂直剖面,主要通过对地质和地球物理资料的综合分析来揭示构造带的性质及其空间关系。横断面的研究所采用的数据基本包括100 km宽区域地质图、上地壳的地质剖面图、重磁图(沿横断面的重磁剖面图)以及地壳的地震波速... 详细信息

地学断面是指地壳的垂直剖面,主要通过对地质和地球物理资料的综合分析来揭示构造带的性质及其空间关系。横断面的研究所采用的数据基本包括100 km宽区域地质图、上地壳的地质剖面图、重磁图(沿横断面的重磁剖面图)以及地壳的地震波速度、密度和其他地球物理属性的剖面图。这些数据被用于构建综合的数据剖面图(结果图),以展示各种地球动力学条件下(裂谷、海洋、碰撞带、造山盆地、大陆地台和岩浆弧,包括安第斯岛弧、活动大陆边缘、海沟、弧前和弧后盆地)的特定的岩石组构。本项目的研究目标是根据研究区现存的地质和地球物理数据的综合解释,统一图例,建立研究区深部剖面,以确定地体的空间关系及其在板块构造方面的地球动力学性质。前人已分别对东西伯利亚南部和蒙古境内的多个地体进行了构造划分,并对它们的地球动力学性质和时空关系进行了分析。研究结果显示该系列地体为早古生代、中晚古生代和晚古生代—早中生代的岛弧和微大陆。此外,研究还识别出了中-晚古生代和晚古生代-早中生代安第斯型活动大陆边缘、晚古生代-早中生代被动大陆边缘和早白垩世裂谷。与岛弧和安第斯型活动大陆边缘相关的岩体被推覆至相邻大陆和微陆块上,部分推覆宽度可达150 km。目前已开展泥盆纪到晚侏罗世时期蒙古鄂霍次克海地区的古地球动力学重建。“非地槽”型花岗岩类岩浆作用在板块构造方面找到了直接且合理的解释,其中泥盆纪-石炭纪和二叠纪-三叠纪岩浆作用区域对应于安第斯型活动大陆边缘,中—晚侏罗世岩浆作用则与西伯利亚/蒙古中国大陆板块碰撞有关。碰撞岩浆作用中亚碱性(地幔)元素的存在及其所在的构造区域在很大程度可以说明蒙古鄂霍次克海闭合后,巨厚大陆岩石圈下曾经发生过持续的大洋裂谷活动(地幔热点)。在早白垩世时期,大陆裂谷活动影响到了同一时期正在发生的大陆汇聚作用。西伯利亚南部边界大部分具有安第斯型活动大陆边缘性质,这也是蒙古—鄂霍次克缝合线沿线蛇绿岩数量较少的原因。因为当汇聚大陆一个具有安第斯类型的活动边缘,而另一个具有被动边缘时,前者的大陆地壳会最终逆冲到后者之上,并因此破坏掉先前出露的蛇绿杂岩体。部分被破坏的蛇绿岩块是俯冲带保留下来的海山残余,其可能成为增生俯冲楔体的混沌复合体的一部分。然而,由于快速俯冲作用,这种楔形体在晚二叠世—早侏罗世的积累并不是西伯利亚活动边缘的典型特征。沿地学断面综合的地质和地球物理资料分析表明,亚洲大陆是在显生宙时期由部分前寒武纪微陆块构造拼贴而成的。前寒武纪地块间存在不同宽度的已变形且剥蚀强烈的显生宙火山弧,它们也被归类为特定地体。

关键词：地质地球物理地壳横断面