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Cytomorphological and genetic indicators in the early ontogenesis of the wild and farmed broad whitefish(Coregonus nasus)

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Aquaculture and Fisheries 2023年第3期8卷 261-266页

作者： Aleksandr selyukov Oksana Zhigileva Leonid shuman svetlana selyukova Vera Bogdanova Tyumen state University Institute of BiologyPirogov Street 3Tyumen625043Russia st.petersburg branch of the All-Russian Research Institute of Fisheries and Oceanography(st.petersburg branch of VNIRO) St.Petersburg199155Russia

The qualitative and quantitative composition of primordial germ cells(PGCs)and the genetic variability of embryos of the Coregonus nasus from the Ob river basin and domesticated population breeding outside the natural areal was *** the broad whitefish,typical,binuclear,polymorphic nuclei cells,as well as PGCs represented primary gonocytes during embryogenesis in *** hatching larvae PGCs mitoses were noted only in domesticated *** genetic variability of embryos of the broad whitefish was studied by polymerase chain reaction of inter simple sequence repeats(IssR-PCR).The high polymorphism of the broad whitefish cultured population was *** proportion of polymorphic bands was 89.4%,Nei’s genetic diversity was *** of the domesticated broad whitefish did not affect the overall level of polymorphism of neutral DNA *** findings suggest the preservation of cytomorphological and genetic diversity in *** embryo from different sources.

关键词： Broad whitefish Domestic brood stock Wild population Embryogenesis Genetic polymorphism Primordial germ cells

synchronous machine performance under geomagnetic disturbances

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High Voltage 2021年第5期6卷 894-903页

作者： Ilja Boguslawsky Nikolay Korovkin Victor Popov Olga sokolova Peter the Great st.petersburg Polytechnic University St.PetersburgRussia Paul scherrer Institute(PsI) VilligenSwitzerland

Geomagnetic disturbances(GMDs)are known to disturb power system equipment *** danger is associated with geomagnetically induced currents(GICs)occurring at the Earth's surface during *** do not endanger power system operation conditions by *** main challenge posed by GICs to power system states is the change in power system equipment operation conditions provoked by GIC *** primary avenue of blackout caused by GMDs is through power ***,in turn,can impair the operation of other power system equipment such as syn-chronous *** powerful synchronous machines are not designed and engineered to cope with the negative impacts of ***,the actual legal norms are inadequate in this *** the grid's resiliency to such an event is highly interesting to the *** physical processes in synchronous machine windings triggered by GICs and limitations brought to power grid operations are ***,the idea of the impact of GMDs on the power grid operation is *** analysis of the impact of GMDs on synchronous machines is performed in the second *** the end,the power system response under GMDs is studied.

关键词： geomagnetic Earth performance

Ordered exponential and its features in Yang-Mills effective action

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Communications in Theoretical Physics 2023年第8期75卷 119-127页

作者： A V Ivanov N V Kharuk st.petersburg Department of steklov Mathematical Institute of Russian Academy of sciences 27 FontankaSt.Petersburg 191023Russia Leonhard Euler International Mathematical Institute 10 Pesochnaya nab.St.Petersburg 197022Russia

In this paper,we discuss some non-trivial relations for ordered exponentials on smooth Riemannian *** an example of application,we study the dependence of the four-dimensional quantum Yang–Mills effective action on the special gauge transformation with respect to the background ***,we formulate some open questions about a structure of divergences for a special type of regularization in the presence of the background field formalism.

关键词： Yang-Mills effective action ordered exponential heat kernel Green's function short-distance asymptotics cutoff regularization synge's world function

Efficient solvothermal synthesis of Defect-Rich Cu-BTC•MOF with Enhanced Electrocatalytic Activity in Alkaline Hydrogen Evolution Reaction

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Transactions of Tianjin University 2024年第6期30卷 508-517页

作者： Maria Timofeeva Dmitry s.Dmitriev Danil D.Maltsev Artem A.Lobinsky Valentina V.Ivashchenko svyatoslav A.Povarov Daria V.Dogadina Alexander s.Timin Valentin A.Milichko Vadim I.Popkov sergei A.shipilovskikh ITMO University St.PetersburgRussia 191002 Ioff e Institute St.PetersburgRussia 194021 Peter the Great st.petersburg Polytechnic University St.PetersburgRussia 195251 Institut Jean Lamour Universit´E de Lorraine54000 NancyFrance

Porous metal–organic frameworks(MOFs) have been recently discovered to be efficient catalysts for energy applications and green technologies. Here, we report on a scalable catalytic platform using Cu–based MOFs for electrocatalytic alkaline hydrogen evolution reaction. First, the solvothermal synthesis of Cu–BTC MOFs(BTC = 1,3,5–benzenetricarboxylate) at 85 ℃ and a 1:60 ligand–to–solvent ratio allowed for minimizing the chemical consumption. second, the obtained platform demonstrated enhanced electrochemical performance compared with commercially available Cu–based MOFs, with a potential of –230 versus –232 eV, logarithm of the current density of –3.6 versus –4.2 cm2, and electrochemical surface area of 75 versus 25 cm2per cm2of geometric area, respectively. Morphological and Raman analyses also revealed that the high concentration of defects in the obtained submicron Cu–BTC MOFs can contribute to their improved catalytic performance. Thus, our findings pave the way to the low–cost synthesis of energy–efficient MOF–based catalysts for hydrogen production.

关键词： Electrocatalysis Metal-organic frameworks Hydrogen evolution reaction Copper-based solvothermal synthesis

Paleoproterozoic Underwater Volcanism and Microfossil-Like structures in the Metasedimentary siliceous Rocks,Hogland Island,Russia

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Journal of Earth science 2018年第6期29卷 1431-1442页

作者： Anatoly M.Belyaev Institute of Earth sciences St.Petersburg State University

Geological surveys showed that rhyolite and basalt strata with pillow structures typical for underwater volcanism form sheets over the svecofennian basement. Original geochemical and isotope-geochemical data confirmed that the rhyolites were formed contemporaneously with the rapakivi granites of the Wiborg Massif（1 640 Ma）, and the basalts are similar to gabbro-anorthosites. Abnormally high content of K2O and relatively low content of Na2O in rhyolites and basalts are interpreted as a result of hydrothermal interaction of eruptive magmas with K-enriched hot seawater. The strata of siliceous metasedimentary rocks（microquartzites） within basaltic and rhyolitic lavas were formed in processes of chemogenic sedimentation and subsequent contact metamorphism during underwater volcanism. Microquartzites showed carbon vastly depleted of heavy isotope 13С. This is typical for rocks formed with participation of living substance. The Raman spectra of the remaining carbon-containing substance have graphite bands. In the microquartzites among basalts and rhyolites we found a community of structures with external and internal morphology similar to modern or fossilized marine microorganisms： spiral cyanobacterias, amoebas, diatoms, foraminifers, virus capsids, flagellates and multicellular organisms. It is assumed that these silificated and ferruginizated microfossils represent the Paleoproterozoic community of marine microorganisms.

关键词： submarine volcanism siliceous rocks silification Paleoproterozoic microfossils carbon isotopes

High-strength Nanostructured Cold-Resistant steels for Continental shelf Development

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Journal of Iron and steel Research International 2011年第S1期18卷 66-71页

作者： Oryshchenko A s Khlusova E I Orlov V V FsUE CRIsM PROMETEY St.PetersburgRussia

The article describes principles of developing steels for maritime structures and main *** scientific approach lies in forming an ultra fine-grained and submicrocrystal structure through thermomechanical treatment of low-carbon low-alloyed steels,providing higher strength and resistance to brittle *** article presents results of assessing the operability characteristics and introducing new steels.

关键词： low-alloyed steels microstructure mechanical properties thermomechanical treatment

study Over Thermal state of Gas Turbine Engine Metal-ceramic Rotor Blades and Nozzle Guide Vanes Under Thermal shock and Thermal-cyclic Loading Conditions

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Journal of Thermal science 2004年第2期13卷 163-166页

作者： A.V.sOUDAREV A.A. sOURYANINOV V.Ya. PODGORETs V.V.GRIsHAEV V.Yu. TIKHOPLAV A.s. MOLCHANOV B.V. sOUDAREV Research-Engineering "Ceramic Heat Engines" Center St.Petersburg Russia

To ensure a reliable operation of the 2.5 MW gas turbine engine (GTE- 2.5) with the inlet gas temperature TIT = 1623 K, studies were performed over the thermal state of the nozzle guide vanes and rotor blades with the temperatures, rates and flows of the working media and cooling air simulating all the potential turbine stage operating duties. The steady state and thermal-cyclic tests having been accomplished, there was no visible defect on the rotor blades and the nozzle vanes. Afterwards, they survived the endurance tests at the rated cooling. Therefore, the functionality of the shell thin-wall hybrid nozzle vanes and rotor blades under the variable operating duties of the gas turbine at the 'shock' and 'cyclic' loads of the working media temperature variations has been demonstrated.

关键词： metal-ceramic blades high temperature thermal-cyclic loading

Valley-dependent topological edge states in plasma photonic crystals

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Plasma science and Technology 2023年第3期25卷 6-14页

作者：李健飞周晨姚静锋袁承勋王莹周忠祥张景文 Anatoly A KUDRYAVTsEV school of Physics Harbin Institute of TechnologyHarbin 150000People’s Republic of China Heilongjiang Provincial Key Laboratory of Plasma Physics and Application Technology Harbin 150000People’s Republic of China Physics Department St.Petersburg State UniversitySt.Petersburg 198504Russia

Plasma photonic crystals designed in this paper are composed of gas discharge tubes to control the flow of electromagnetic *** band structures calculated by the finite element method are consistent with the experimental results which have two distinct attenuation peaks in the ranges of 1-2.5 GHz and 5-6 *** parameters of the plasma are extracted by the Nicolson-Ross-Weir method and effective medium *** measured electron density is between 1×1011 cm-3 and1×1012 cm-3,which verifies the correctness of the parameter used in the simulation,and the collision frequency is near 1.5×1010 *** the band structures are corroborated by the measured scattering parameters,we introduce the concept of photonic topological insulator based on the quantum Valley Hall effect into the plasma photonic crystal.A valley-dependent plasma photonic crystal with hexagonal lattice is constructed,and the phase transition of the valley K(K’)occurs by breaking the spatial inversion ***-spin locked topological edge states are generated and excited by chiral *** frequency of the non-bulk state can be dynamically regulated by the electron *** concept paves the way for novel,tunable topological edge *** interestingly,the Dirac cone is broken when the electron density increases to 3.1×1012 cm-3,which distinguishes from the methods of applying a magnetic field and changing the symmetry of the point group.

关键词： plasma photonic crystal valley-dependent topological state electron density

Microwave diagnostics of pulsed atmospheric discharge with electrolytic electrode and long-lived luminous formation in its afterglow

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High Voltage 2024年第1期9卷 127-136页

作者： shixin Zhao Xingbao Lyu Aleksandr Astafiev Chengxun Yuan Lin Miao Jingfeng Yao Ying Wang Anatoly Kudryavtsev Aleksandr Chirtsov Gennadii shabanov Zhongxiang Zhou school of Physics Harbin Institute of TechnologyHarbinChina Physics Department Saint Petersburg Electrotechnical University“LETI”St.PetersburgRussia Heilongjiang Provincial Key Laboratory of Plasma Physics and Application Technology HarbinChina Physics Department St.Petersburg State UniversitySt.PetersburgRussia Konstantinov petersburg Nuclear Physics Institute National Research Centre“Kurchatov Institute”GatchinaRussia

The Gatchina discharge phenomenon holds significant promise as a laboratory model for simulating ball ***,crucial aspects concerning the plasma components of the resulting afterglow remain ***,the measurement of the electron density,a critical parameter,has not been fully achieved thus *** this study,microwave diagnostics and video recording were employed during a pulsed Gatchina discharge,along with synchronous measurement of discharge current and *** antennas were positioned at different heights to enable separate diagnosis of the discharge and the ensuing long-lived *** findings revealed that during the active phase of the Gatchina discharge,the plasma density was substantial enough to cause reflection of an electromagnetic wave with a frequency of 20 GHz from this highly conductive *** the afterglow,the signal experienced only a moderate weakening of 10–20 percent,facilitating the determination of the time dependence of average electron density during the afterglow's passage between the two *** measurements verified the unusually slow plasma decay in the afterglow of the Gatchina discharge,suggesting the potential significance of chemi-ionisation processes involving long-lived(metastable)particles.

关键词： holds luminous electrolytic