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Preface: Stars and interstellar medium

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Research in Astronomy and Astrophysics 2018年第8期18卷 1-3页

作者： nikolay n.samus Yan Li Institute of Astronomy Russian Academy of Sciences Yunnan Observatories Chinese Academy of Sciences

This issue presents proceedings of the ＂Stars and Interstellar Medium＂ section of the All- Russian Astronomical Conference VAK-2017. Sixteen papers （selected from about 70 talks） cover dif- ferent problems related... 详细信息

关键词： stars: binaries - ISM general - ISM clouds

The Fifth Edition of the General Catalogue of Variable Stars:experiences in the constellation Centaurus

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Research in Astronomy and Astrophysics 2018年第7期18卷 93-100页

作者： nikolay n.samus Elena n.Pastukhova Olga V.Durlevich Elena V.Kazarovets Institute of Astronomy Russian Academy of Sciences Sternberg Astronomical Institute Lomonosov Moscow University

We have recently announced that the General Catalogue of Variable Stars enters the stage of its fifth, purely electronic edition （GCVS 5.1）. We have included 1408 variable stars in the constellation Centaurus in this new version, GCVS 5.1. Working on this revision, we applied current possibilities from data mining, suggested new variability types for many variable stars and found new light elements for a large number of periodic variables. This paper describes the work completed during the preparation of GCVS 5.1 for Centaurus and discusses in detail a number of the most astrophysically significant cases.

关键词： catalogs - techniques photometric - stars variables general - binaries eclipsing

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

new variable stars from the photographic archive:semi-automated discoveries,attempts at automatic classification and the new field 104 Her

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Research in Astronomy and Astrophysics 2018年第8期18卷 29-40页

作者： Sergei V.Antipin Ignacio Becker Alexander A.Belinski Darya M.Kolesnikova Karim Pichara nikolay n.samus Kirill V.Sokolovsky Alia V.Zharova Alexandra M.Zubareva P.K.Sternberg Astronomical Institute M.V.Lomonosov Moscow University13University Ave.Moscow 119234Russia Pontificia Universidad Catolica de Chile SantiagoChile Institute of Astronomy Russian Academy of Sciences48Pyatnitskaya Str.Moscow 109017Russia Institute for Applied Computational Science Harvard UniversityCambridgeMAUSA IAASARS National Observatory of Athens15236 PenteliGreece Astro Space Center of Lebedev Physical Institute Profsoyuznaya Str.84/32Moscow 117997Russia

Using 172 plates taken with the 40-cm astrograph of the Sternberg Astronomical Institute （Lomonosov Moscow University） in 1976-1994 and digitized with a resolution of 2400dpi, we dis- covered and studied 275 new variable stars. We present the list of our new variables with all necessary information concerning their brightness variations. As in our earlier studies, the new discoveries show a rather large number of high-amplitude Delta Scuti variables, predicting that many stars of this type re- main not detected in the whole sky. We also performed automated classification of the newly discovered variable stars based on the Random Forest algorithm. The results of the automated classification were compared to traditional classification and showed that automated classification was possible even with noisy photographic data. However, further improvement of automated techniques is needed, which is especially important when considering the very large numbers of new discoveries expected from all-sky surveys.

关键词： techniques photometric

Ion-conducting Membranes Based on Bacterial Cellulose nanofibers Modified by Poly(sodium acrylate-co-2-acrylamido-2-methylpropanesulfonic acid)

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Chinese Journal of Polymer Science 2024年第3期42卷 333-343,I0007页

作者： Elizaveta V.Batishcheva nikolay n.Smirnov natalya V.Bobrova Maria P.Sokolova Michael A.Smirnov Institute of Macromolecular Compounds Russian Academy of SciencesBolshoy pr.31Saint Petersburg 199004Russia

Green method for preparation of ion-conducting membranes(ICM) based on bacterial cellulose nanofibers(CnF) modified by a copolymer of sodium acrylate and 2-acrylamido-2-methylpropanesulfonic acid was elaborated. FTIR and nMR data confirmed grafting of polyacrylate onto cellulose surface. Formation of porous structure of the ICM was controlled by SEM and AFM. The maximal ionic conductivity of the membranes reaches 1.5 and 3.1 mS·cm^(-1)(60 ℃ and 98% relative humidity) when they are saturated with water or H_2SO_4(1 mol·L^(-1)) electrolyte,respectively. Prepared ICM was tested as a separator in a symmetrical supercapacitor with electrodes based on polyaniline hydrogel. The assembled cell demonstrate ability to operate at high current density up to 100 A·g^(-1) maintaining specific capacitance 165 F·g^(-1). Maximal specific capacitance of 289 F·g^(-1) was achieved at current density 1 A·g^(-1). Retaining of 90% of initial capacitance after 10000 of charge-discharge cycles proves high electrochemical stability of prepared ICM.

关键词： Bacterial cellulose Ion conductivity Porous membrane Supercapacitor

Self-healable and Robust Film Based on Electroactive Polymer Brush as Electrode for Flexible Supercapacitor

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Chinese Journal of Polymer Science 2024年第8期42卷 1049-1059页

作者： Maria P.Sokolova Vitaly K.Vorobiov nikolay n.Smirnov Ivan S.Kuryndin natalya V.Bobrova Michael A.Smirnov Institute of Macromolecular Compounds Russian Academy of SciencesBolshoy pr.31Saint Petersburg 199004Russia

The aim of this study was to develop self-healable and robust elect roconductive film based on polyaniline copolymer for application as electrode in flexible *** this purpose,the electroconductive polymer brushes(EPB)was *** synthesis of EPB is based on graft polymerizations of acrylamide(AAm)on poly(vinyl alcohol)(PVA)with formation of PVA-PAAm polymer brush and subsequent graft copolymerization of aniline and p-phenylenediamine on PVA-PAAm resulting in formation of EPB with electroconducting copoly(aniline-co-pphenylenediamine)(PAPh DA).It was found that the ratio between PVA and PAAm at the first stage greatly influence the electrochemical performance of the *** films were prepared by casting of EPB solution with subsequent *** of electrical current distribution through the film with AFM reveal more uniform distribution of PAPhDA in EPB in comparison with reference PVA-PAPhDA and PAAm-PAPhDA *** was demonstrated that mechanical cha racteristics and electrical conductivity values of films restore at large extent after curring and self-healing under optimal relative humidity level(58%).The flexile supercapacitor cell with EPB film electrodes demon strate specific capacitance 602 mF·cm^(-2)at the current density of 1 mA·cm^(-2)and retention 94%of initial capacitance after 5000 charge/discharge cycles.

关键词： Polymer brush Polyaniline Flexible supercapacitor Self-healing Electroconducting film

Kinetics and mechanism of the low-energy b-a phase transition of the second kind in 2,4-dinitroanisole

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Defence Technology（防务技术） 2024年第10期40卷 210-224页

作者： Aleksandr V.Stankevich nikolay A.Rasputin Anisa KhRudina Gennady L.Rusinov Vera I.Filyakova Valery n.Charushin y1.postovsky institute of organic synthesis ural branch of the russian academy of sciencesekaterinburg 620108russia russian federal nuclear center e zababakhin all-russia research institute of technical physics snezhinsk 456770russia kazan national research technological university kazan 420015russia

In this work,comprehensive studies of 2,4-dinitroanisole(2,4DnAn)were carried out using powder thermorentgenography of the internal *** time of the complete polymorphic transition in the solid phase b/a in 2,4DnAn under various combinations of conditions has been *** has been established that,regardless of the season of manufacture of the substance,when it is stored for 8e9 months,with a change in ambient temperature from minus 30℃ to plus 30℃,a complete polymorphic transition b/a *** stored in conditions below minus 5℃,polymorphic transition does not *** stored in conditions above plus 30℃ in a closed container,polymorphic transition occurs within 3 *** polymorphic transition is accompanied by a decrease in density by 1.3%e1.5%and an increase in melting temperature by 10-12℃,depending on the degree of purity of the starting *** activation energy of the molecular rearrangement was 68e70 kJ/mol(16.5±3 kcal/mol).The mechanism of polymorphic transition has been evaluated,which is presumably based on internal homodiffusion and energy transfer to the surface of the mass of powder particles and the *** average activation energy of the polymorphic transition process was 110±6.2 kJ/mol(26.2 kcal/mol).In an open container,reactions proceed by a homogeneous mechanism,and in a closed container by a heterogeneous mechanism involving the gas phase.

关键词： Energetic materials Melt-castable 2,4-Dinitroanisole Polymorphic transition Kinetics Mechanism Homodiffusion Sublimation

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超表面:塑造光子学的未来

Science Bulletin 2024年第11期69卷 1607-1611页

作者： nikolay L.Kazanskiy Svetlana n.Khonina Muhammad A.Butt Samara national Research University Samara 443086Russia

A metasurface, often abbreviated as MS, represents a thin, artificially crafted surface consisting of an assembly of subwavelength structures that interact with light in distinct manners. Typically,smaller than the wavelength of the light they engage with, these structures empower precise management of light properties such as polarization, phase, and amplitude.

关键词： precise abbreviated 光子学

The biosynthetic pathway of the hallucinogen mescaline and its heterologous reconstruction

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Molecular Plant 2024年第7期17卷 1129-1150页

作者： Paula Berman Luis Alejandro de Haro Ana-Rita Cavaco Sayantan Panda Younghui Dong nikolay Kuzmich Gabriel Lichtenstein Yoav Peleg Hila Harat Adam Jozwiaki Jianghua Cai Uwe Heinig Sagit Meir Ilana Rogachev Asaph Aharoni Department of Plant and Environmental Sciences Weizmann Institute of ScienceRehovot 7610001Israel Life Sciences Core Facilities Weizmann Institute of ScienceRehovot 7610001Israel The Maurice and Vivienne Wohl Institute for Drug Discovery Weizmann Institute of ScienceRehovot 7610001Israel Present address:Department of Cell and Metabolic Biology Leibniz Institute of Plant BiochemistryWeinberg 306120 Halle(Saale)Germany Department of Molecular&Cellular Pharmacology University of Miami Miler School of MedicineMiamiFL 33136USA Department of Botany and Plant Sciences University of California RiversideRiversideCA 92521USA Laboratory of Plant Hormones and Development Regulation of Chongqing School of Life SciencesChongqing UniversityChongqing 401331China

Mescaline,among the earliest identified natural hallucinogens,holds great potential in psychotherapy ***,despite the existence of a postulated biosynthetic pathway for more than half a century,the specific enzymes involved in this process are yet to be *** this study,we investigated the cactus Lophophora williamsii(Peyote),the largest known natural producer of the phenethylamine *** employed a multi-faceted approach,combining de novo whole-genome and transcriptome sequencing with comprehensive chemical profiling,enzymatic assays,molecular modeling,and pathway engineering for pathway *** identified four groups of enzymes responsible for the six catalytic steps in the mescaline biosynthetic pathway,and an n-methyltransferase enzyme that n-methylates all phenethylamine intermediates,likely modulating mescaline levels in ***,we reconstructed the mescaline biosynthetic pathway in both nicotiana benthamiana plants and yeast cells,providing novel insights into several challenges hindering complete heterologous mescaline *** together,our study opens up avenues for exploration of sustainable production approaches and responsible utilization of mescaline,safeguarding this valuable natural resource for future generations.

关键词： mescaline Lophophora williamsi Peyote biosynthetic pathway de novo genome sequencing mo-lecular modeling