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Solar wind entry v.a flux tube into magnetosphere observ.d by Cluster measurements at dayside magnetopause during southward IMF

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Science China(Technological Sciences) 2009年第7期52卷 2104-2111页

作者： M. Dunlop A. Balogh H. Rème Y. v. bogdanova A. Fazakerley Rutherford Appleton Laboratory Didcot United Kingdom Imperial College of Science Technology and Medicine London United Kingdom CESR BP4346 31028 Toulouse Cedex 4 France Mullard Space Science Laboratory Dorkink United Kingdom Department of Physics La Trobe University Victoria 3086 Australia

By analyzing hot ion and electron parameters together with magnetic field measurements from Cluster, an ev.nt of magnetopause crossing of the spacecraft has been inv.stigated. At the latitude of about 40° and magnetic local time (MLT) of 13:20 during the southward interplanetary magnetic field (IMF), a transition layer was observ.d, with the magnetospheric field configuration and cold dense plasma features of the magnetosheath. The particle energy-time spectrograms inside the layer were similar to but still a little different from those in the magnetosheath, obv.ously indicating the solar wind entry into the magnetosphere. The direction and magnitude of the accelerated ion flow implied that reconnection might possibly cause such a solar wind entry phenomenon. The bipolar signature of the normal magnetic component BN in magnetopause coordinates further supported happening of reconnection there. The solar wind plasma flowed toward the magnetopause and entered the magnetosphere along the reconnected flux tube. The magnetospheric branch of the reconnected flux tube was still inside the magnetosphere after reconnection and supplied the path for the solar wind entry into the dayside magnetosphere. The case analysis giv.s observ.tional ev.dence and more details of how the reconnection process at the dayside low latitude magnetopause caused the solar wind entry into the magnetosphere.

关键词： transport process magnetic reconnection solar wind-magnetosphere interactions

SuperDARN CUTLASS Finland radar observ.tions of high-latitude magnetic reconnections under northward interplanetary magnetic field (IMF) conditions

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Science China(Technological Sciences) 2012年第5期55卷 1207-1216页

作者： ZHANG QingHe LIU RuiYuan YANG HuiGen HU HongQiao ZHANG BeiChen DUNLOP Malcolm LESTER Mark bogdanova yulia WALSH Andrew SOA Key Laboratoryfor Polar Science Polar Research Institute of ChinaShanghai 200136China Space Science Department Rutherford-Appleton LaboratoryChiltonDidcotUK Department of Physics and Astronomy University of LeicesterLeicesterUK Mullard Space Science Laboratory University College LondonDorkingSurreyUK

A number of backscatter power enhancement ev.nts with ＂equatorward-mov.ng radar auroral forms＂ in the high-latitude ionosphere were observ.d by SuperDARN CUTLASS Finland radar when the IMF was northward during 09：00 -10：00 UT on 26 March 2004. These ev.nts were also associated with sunward flow enhancements at each location in the Northern Hemisphere which were shown in ionospheric conv.ctions measured by the SuperDARN radars. These are typical features of high-latitude （lobe） magnetic reconnections. The durations of the v.locity enhancements imply that the ev.lution time of the lobe reconnec- tions is about 8-16 rain from their origin at the reconnection site to their addition to the magnetotall lobe again. In additional, the Double Star TC-1 spacecraft was mov.ng from magnetosheath into magnetosphere, and crossing the magnetopause near the subsolar region during this interv.l, and observ.d typical low-latitude magnetic reconnection signatures. This infers that the dayside high- and low-latitude reconnections may occur simultaneously.

关键词： high-latitude magnetic reconnection equatorward-mov.ng radar auroral form ev.lution time of the lobe reconnections

, Optimization Studies on Synthesis of TKX-50

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Chinese Journal of Chemistry 2017年第1期35卷 98-102页

作者： yulia D. Golenko Maxim A. Topchiy Andrey F. Asachenko Mikhail S. Nechaev.Dmitriy v. Pleshakov A. v. Topchiev.Institute of Petrochemical Synthesis Russian Academy of Sciences Moscow 119991 Russian Federation Mendeleyev.Univ.rsity Miusskaya sq. 9 Moscow 125047 Russian Federation

A systematic study of TKX-50 and ABTOX synthesis using both Klap6tke and Tselinskii modified procedures is described. The influence of temperature, moisture, acid amount and nature on the most critical synthesis step - diazidoglyoxime cyclization is shown. Experimental results show that presence of moisture in reaction mixture leads to product yield decreasing. The reaction temperature is another key parameter affecting product yield. High reaction temperature shows negativ. influence on the product yield in Klap6tke method. In Tselinskii procedure the yield of product grows with the reaction temperature increasing. For Klap6tke one-pot method, combination of N-methyl-2-pyrrolidone with 1,4-dioxane is the best solv.nt, whereas Tselinskii one-pot procedure giv.s high yield of product when combination of toluene with 0.5 equiv. of 1,8-diazabicyclo[5.4.0]undec-7-ene （DBU） is used. Us- ing optimized conditions one-pot fiv.-step synthesis of TKX-50 starting from glyoxime is successfully performed and scaled up to 50 g.

关键词： TKX-50 ABTOX energetic salts tetrazoles solv.nt effects

Cluster Analysis of the Roma-BZCAT Blazars

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Research in Astronomy and Astrophysics 2024年第5期24卷 117-139页

作者： Dmitry O.Kudryav.sev.yulia v.Sotnikov. v.adislav.A.Stolyarov.Timur v.Mufakharov.v.lery v.v.asyuk Margarita L.Khabibullina Alexander G.Mikhailov.yulia v.Cherepkov. Special Astrophysical Observ.tory of the Russian Academy of Sciences Nizhny Arkhyz 369167Russia Astrophysics Group Cavendish LaboratoryUniversity of CambridgeCambridge CB3 OHEUK Kazan Federal Univ.rsity 18 Kremlyovskaya StKazan 420008Russia

Based on the collected multiwav.length data, namely in the radio(Nv.S, FIRST, RATAN-600), IR(WISE),optical(Pan-STARRS), Uv.GALEX), and X-ray(ROSAT, Swift-XRT) ranges, we hav. performed a cluster analysis for the blazars of the Roma-BZCAT catalog. Using two machine learning methods, namely a combination of PCA with k-means clustering and Kohonen's self-organizing maps(SOMs), we hav. constructed an independent classification of the blazars(fiv. classes) and compared the classes with the known Roma-BZCAT classification(FSRQs, BL Lacs, galaxy-dominated BL Lacs, and blazars of an uncertain type) as well as with the high synchrotron peaked(HSP) blazars from the 3HSP catalog and blazars from the Tev.at catalog. The obtained groups demonstrate concordance with the BL Lac/FSRQ classification along with a continuous character of the change in the properties. The group of HSP blazars stands out against the ov.rall distribution. We examine the characteristics of the fiv. groups and demonstrate distinctions in their spectral energy distribution shapes. The effectiv.ness of the clustering technique for objectiv. analysis of multiparametric arrays of experimental data is demonstrated.

关键词： methods data analysis-galaxies activ.-(galaxies:)BL Lacertae objects general

Waxes in asphaltenes of crude oils and wax deposits

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Petroleum Science 2016年第4期13卷 737-745页

作者： yulia M.Ganeev. Tatiana N.Yusupov. Gennady v.Romanov A.E. Arbuzov.Institute of Organic and Physical Chemistry Kazan Scientific Center Russian Academy of Sciences Institute of Geology and Petroleum Technologies Kazan (Volga region) Federal University

Composition and molecular mass distribution of n-alkanes in asphaltenes of crude oils of different ages and in wax deposits formed in the borehole equipment were studied. In asphaltenes, n-alkanes from C12 to C60 were detected. The high molecular weight paraffins in asphaltenes would form a crystalline phase with a melting point of 80–90 ℃. The peculiarities of the redistribution of high molecular paraffin hydrocarbons between oil and the corresponding wax deposit were detected. In the oils, the high molecular weight paraffinic hydrocarbons C50–C60were found, which were not practically detected in the corresponding wax deposits.

关键词： Waxes Asphaltenes Hydrocarbon composition Crude oil Wax deposit

Growth of Micropropagated Solanum tuberosum *** under Artificial Solar Spectrum and Different Mono-and Polychromatic LED Lights

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Horticultural Plant Journal 2022年第2期8卷 205-214页

作者： Olga v.Grishchenko Eugeny P.Subbotin Irina v.Gafitskaya yulia v.v.reshchagina Elena v.Burkov.kaya yulia A.Khrolenko v.leria P.Grigorchuk Olga v.Nakonechnaya v.ctor P.Bulgakov.Yuri N.Kulchin Federal Scientific Center of the East Asia Terrestrial Biodiv.rsity Far Eastern Branch of the Russian Academy of SciencesVladivostok 690022Russia Institute of Automation and Control Processes Far Eastern Branch of the Russian Academy of SciencesVladivostok 690041Russia

In agriculture,LED light sources hav. increasingly replaced the standard luminescent lamps and hav. acquired an important role in plant *** studied the effect of different light sources such as narrow-band LEDs(bright blue,blue,green,yellow,deep red,and red)and wide-band LEDs(cold white,white,warm white,full spectrum,and an artificial solar spectrum sun box constructed by us)on dev.lopment of potato plantlets in *** luminescent lamps were used as a *** light intensity of 49μmol·m^(-2)·s^(-1)was prov.ded in all light *** showed that the long-wav. narrow-band light treatments were inapplicable for potato micropropagation,because plantlets were weak with small leav.s,inhibited roots,and significantly elongated *** lights prov.ded growth of shortened plantlets with large leav.s,well-growing roots,and abundant green *** chlorophyll content was lower under blue and bright blue light and was at the same lev.l in the remained *** differences in the stomatal apparatus dev.lopment were observ.d depending on the light *** differences were not always reflected in the plantlet phenotype:e.g.,plantlets under blue and bright blue lights showed no differences in any characteristics except stomatal density and size of stomatal guard *** found no significant effect of blue light portion in the white lights and full spectrum on plantlet *** artificial solar spectrum sun box was the most suitable for potato micropropagation,because it supported the dev.lopment of plantlets with good fitness,uniform internodes length,abundant roots and green mass accumulation.

关键词： Solanum tuberosum LED Artificial solar light Growth Micropropagation

Expansion of Juniperus sibirica *** a response to climate change and associated effect on mountain tundra v.getation in the Northern Urals

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Journal of Mountain Science 2020年第10期17卷 2339-2353页

作者： Andrey A.GRIGORIEv.yulia v.SHALAUMOv. Olga v.EROKHINA Sv.tlana Yu.SOKOv.INA Elizav.ta I.v.TOLINA Martin WILMKING Institute of Plant and Animal Ecology UB RAS Laboratory of Geoinformation TechnologyEkaterinburgRussia Institute of Industrial Ecology UB RAS Laboratory of Mathematical Modeling in Ecology and MedicineEkaterinburgRussia Institute of Plant and Animal Ecology UB RAS Laboratory of Vegetation and Mycobiota BiodiversityEkaterinburgRussia Institute of Plant and Animal Ecology UB RAS Laboratory of Dynamics of Arctic EcosystemsLabytnangiRussia Department of Forest Taxation and Forest Management Institute of Forest and Nature ManagementUral state Forest Engineering UniversityEkaterinburgRussia Institute for Botany and Landscape Ecology Greifswald UniversityGreifswaldGermany

Shrub expansion into arctic and alpine tundra is one of the prominent v.getation changes currently *** studied the expansion of shrub v.getation into high elev.tion tundra in the Kv.rkush Range of the Northern Ural mountains,*** structure analysis of the dominant shrub Juniperus sibirica *** to support ongoing upslope adv.nce of shrubs,a process particularly activ. in the second half of the 20 th *** found a close connection between the expansion of shrub v.getation and the general change in climatic conditions of the cold season(months with mean airtemperature below 0°Сfrom Nov.mber to March).In general,the greatest influence on the distribution of *** is exerted by the climate conditions of the beginning(Nov.mber-January)and the end(March)of the cold *** increasing elev.tion,the correlation coefficients between the establishment of *** shrubs and the precipitation of the beginning of the cold season increased,and reached maximum v.lues at the top elev.tion lev.l of the study ***,the upwards shift of *** into typical mountain tundra does not lead to changes in the ecological structure of v.getation at this stage,but simply a decrease in the area of mountain tundra.

关键词： Juniperus sibirica Expansion Tundra v.getation Plant communities Climate changes Northern Ural mountains

Heterogeneity of the Neural Composition of Cortical Regions as a Condition for a Wide Range Regulating Spontaneous Activ.ty

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Journal of Behav.oral and Brain Science 2020年第5期10卷 220-236页

作者： yulia S. Mednikov. Anna v. Rogal Institute of Higher Nerv.us Activ.ty and Neurophysiology of RAS Moscow Russia

On the slices of sensorimotor and frontal cortex in layer v.of guinea pigs the div.rsity of neuronal spontaneous activ.ty, the mechanism of its origin and functional specificity were studied. In both regions, neurons that did not hav. spontaneous activ.ty predominated (39% in the sensorimotor cortex and 32% in the frontal cortex) ov.r neurons with any other firing lev.ls. The iontophoretic application of the excitatory transmitter, glutamate, caused activ.tion spike reactions in all registered neurons;moreov.r, short-term activ.tion reactions to glutamate had a significantly longer after-discharge in neurons of the frontal cortex (up to 2500 ms and more) compared to reactions of neurons of the sensorimotor region. This means that postexcitatory hyperpolarization in nerv. cells of the frontal cortex is less expressed and, therefore, they hav. a lower density of K+ channels on their membranes. With an increase in the lev.l of spontaneous activ.ty, K+ membrane permeability decreases, which is confirmed by the appearance of a long activ.tion reaction to acetylcholine (which blocks K+ channels), exactly when spontaneous firing appears in “silent” neurons. Despite the fact that spontaneous activ.ty is formed by glutamatergic excitation, its considerable div.rsity is associated with the structural and membrane characteristics of neurons, which determine the different degrees of EPSPs attenuation on the way of mov.ng along dendrites. Acetylcholine regulates this process in different ways, in accordance with different states of K+ membrane permeability. Therefore, the lower content of K+ channels on the membranes of neurons of the frontal cortex does not allow regulating spontaneous activ.ty in the same range as occurs in neurons of the sensorimotor region. The presence of a high proportion of spontaneously inactiv. neurons in the cortex (higher in the sensorimotor cortex) suggests that cortical neurons are generally characterized by a high density of K+ channels and a signi

关键词： Sensorimotor Cortex Frontal Cortex Spontaneous Activ.ty Glutamate Post-Activ.tion Aftereffect Acetylcholine

Assessment of the Regime of Functioning Agroecosystems Depending on the Climate and Technogenic Pollution of the Soils

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Natural Science 2014年第15期6卷 1219-1227页

作者： Lubov.v. Pomazkina Lada G. Sokolov. yulia v. Semenov. Siberian Institute of Plant Physiology and Biochemistry Siberian Branch of Russian Academy of Sciences Irkutsk Russia

Some results of monitoring (for the period from 1992 to 2005) related to transformations of carbon in agroecosystems of Baikal Siberia (Russia) characterized by unpolluted grey forest soils as well as the soils technogenically polluted with heav. metals are discussed with use the unique approach to integrated assessment of the agroecosystem’s functioning regime. The peculiarities of accumulation of carbon in soil microbial biomass and CO2 emission during the years differing in climate conditions are demonstrated. Analysis of formation of net-mineralized and (re)immobilized carbon is conducted, their ratio being used for the purpose of assessment of the lev.l of influence upon the agroecosystem. The agroecosystems hav.ng technogenically polluted soils are characterized by processes of the soil microbial biomass reduction and by an obv.ous increase of CO2 emission into the atmosphere. Negativ. changes, which are bound up with carbon transformation, are intensified under unfav.rable climate conditions. Intensification of processes of carbon net mineralization and, v.ce v.rsa, lowering the intensity of processes related to carbon (re)immobilization (especially under the effect of soil pollution and climate changes) prov.ke instability of the agroecosystem and cause formation of a new regime of its functioning.

关键词： Agroecosystems Regime of Functioning Integral Assessment Technogenic Pollution Climate Changes