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Changes in the growth of Scots pine(Pinus sylvestris L.)stands in an urban environment in European Russia since 1862

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Journal of Forestry Research 2023年第5期34卷 1279-1287页

作者： Aleksandr v.Lebedev Department of Agricultural Meliorations Forestry and Land OrganizationRussian State Agrarian University-Moscow Timiryazev Agricultural AcademyTimiryazevskaya49MoscowRussia 127434

A century and a half ago,in the European part of Russia(Moscow),forest scientists established the first long-term observations of forests,many of which are under observation to the present *** the twentieth century,climate changes and,due to industrial development,forest areas were under air *** on observations from 157 sites,this study shows that the growth and density of Scots pine(Pinus sylvestris L.)have decreased by the end of the twentieth *** environment has changed,and the growth and development of plantations has *** yields(-34%stand volume)and their life expectancy(on average 50 years)have *** changes are critical for forestry and for the management of forests in urban *** to the decline in growth,ecosystem functions by urban forests has *** order to increase the sustainability of urban forests and the provision of ecosystem services,it is preferable to create multi-species stands with a complex structure.

关键词： Forest stand Scots pine Stand growth Urbanized environment Human footprint

Physical vapor transport growth and morphology of Bi2Se3 microcrystals

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Particuology 2016年第3期14卷 118-122页

作者： v.v. Atuchin S.v. Borisov T.A. Gavrilova K.A. Kokh N.v. Kuratieva N.v. Pervukhina Laboratory of Optical Materials and Structures Institute of Semiconductor Physics SB RAS Novosibirsk 630090 Russia Functional Electronics Laboratory Tomsk State University Tomsk 634050 Russia Laboratory of Semiconductor and Dielectric Materials Novosibirsk State University Novosibirsk 630090 Russia Laboratory of Crystul Chemistry Institute of Inorganic Chemistry SB RAS Novosibirsk 630090 Russia Laboratory of Nanodiagnostics and Nanolithography Institute of Semiconductor Physics SB RAS Novosibirsk 630090 Russia Laboratory of Crystal Growth Institute of Geology and Mineralogy SB RAS Novosibirsk 630090 Russia Geology and Mineralogy Department Novosibirsk State University Novosibirsk 630090 Russia Spintronics Laboratory Saint Petersburg State University Saint Petersburg 198504 Russia Laboratory of Research Methods of Composition and Structure of Functional Materials Novosibirsk State University Novosibirsk 630090 Russia

High-quality Bi2Se3 microcrystals were grown by the physical vapor transport （PvT） method without using a foreign transport agent. The microplate crystals grown under the optimal temperature gradient are well faceted and have dimensions up to -200 μm, The growth proceeds by the layer-by-layer mecha- nism with the formation of flat low-growth rate facets. The phase composition of the grown crystals was identified by the X-ray single crystal structure analysis in space group R3m, a = 4.1356（3）, C= 28.634（5）A, Z=3 （R=0.0147）. The most probable twin planes in the tetradymite structure were evaluated by the pseudo translational sublattice merhad.

关键词： Bi2Se3 Physical vapor transport Structure Twin

3D Kinematics of Classical Cepheids According to Gaia EDR3 Catalog

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Research in Astronomy and Astrophysics 2023年第4期23卷 1-14页

作者： v.v.Bobylev A.T.Bajkova Pulkovo Astronomical Observatory St.-Petersburg 196140Russia

The kinematics of about 2000 classical Cepheids of the Milky Way with data from Gaia EDR3 catalog has been *** some of these stars,there are line-of-sight *** the basis of the nonlinear rotation model,the parameters of the rotation curve of the Galaxy were *** circular linear rotation velocity of the near-solar neighborhood around the Galaxy center was v0=236±3 km s^(−1) for the assumed Sun's galactocentric distance R0=8.1±0.1 *** of residual velocities of Cepheids based on the linear Ogorodnikov–Milne model showed the presence of the following significantly different from zero gradients:∂U/∂x,∂U/∂z,∂v/∂x,∂v/∂z and∂W/∂x,which behave differently depending on the selection *** most interesting is the gradient∂W/∂x∼−0.5±0.1 km s^(−1) kpc^(−1)(positive rotation of this star system around the Galactic axis y,Ωy)since the velocities W are free of Galactic *** we have an indirect influence of various effects leading to a perturbation of the vertical velocities of the Galactic disk *** on a simpler model,a more accurate estimate of this rotation is obtained,Ωy=0.51±0.07 km s^(−1) kpc^(−1).

关键词： stars distances-Galaxy kinematics and dynamics-stars variables Cepheids

Effect of process parameters of pulsed current tungsten inert gas welding on weld pool geometry of titanium welds

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Acta Metallurgica Sinica(English Letters) 2010年第4期23卷 312-320页

作者： M.Balasubramanian v.Jayabalan v.Balasubramanian Department of Mechanical Engineering Velammal Engineering CollegeSurapetAnna University Department of Manufacturing Engineering Anna University Centre for Materials Joining & Research Department of Manufacturing EngineeringAnnamalai University

The effects of pulsing current parameters on weld pool geometry namely front height, back height, front width and back width of pulse current gas tungsten arc welded （GTAW） titanium alloy was analysed. Four factors, five levels, central composite design were used to develop empirical relationships, incorporating pulsed current parameters and weld pool geometry.

关键词： Gas tungsten arc welding Pulsed current Titanium alloy Design of experiments

How Common can the Origin of Clusters Cha Ⅰ, Cha Ⅱ, ∈Cha and η Cha be?

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Research in Astronomy and Astrophysics 2024年第5期24卷 28-34页

作者： v.v.Bobylev A.T.Bajkova Pulkovo Astronomical Observatory St.-Petersburg 196140Russia

The trajectories of the groupings η Cha,∈Cha and Cha I,Cha II,constructed backward in time,have been *** concluded that the hypothesis about the joint formation of all four of these clusters from one molecular cloud cannot be completely ***,10–15 Myr ago,all these four clusters were located at approximately the same height above the plane of the ***,the gas-dust clouds from which all these four clusters were formed were located on one broad *** is possible that the appearance of the Cha I,Cha II,∈Cha and η Cha clusters may be associated with the impact on such a front of shock waves formed after supernova explosions in the Scorpius–Centaurus *** estimates of the kinematic ages of the clusters Cha I and Cha II are obtained as 0.12±0.19 and 0.05±0.15,*** is shown that the minimum size of the Cha I-north and Cha I-south clusters corresponded to the time of 0.55±0.24 Myr and 0.04±0.18 Myr ago,respectively,and approximately1.5 Myr ago the distance between the trajectories of these two groupings was minimal.

关键词： stars distances-stars kinematics and dynamics-galaxies star formation

Effect of types of reinforcement on plastic hinge rotation parameters of RC beams under pushover and cyclic loading

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Earthquake Engineering and Engineering vibration 2015年第3期14卷 503-516页

作者： v.v.S.Surya Kumar Dadi Pankaj Agarwal Department of Civil Engineering Institute of Technology Guru Ghasidas Vishwavidyalaya Bilaspur (C.G.) India Assistant Professor Department of Earthquake Engineering Indian Institute of Technology Roorkee

Experimental evaluation of reinforced concrete beam specimens with different characteristics of reinforcement subjected to pushover and cyclic loading is *** hinge rotation parameters are determined based on the idealization of pushover and hysteresis curves of reinforced concrete beam specimens constructed in two percentage of reinforcement(0.471%and 0.71%) with different ductile *** experimental test results provide a clear demarcation of the effect of types of loading and the types of reinforcement on the nonlinear performance characteristics of beam *** results are helpful to update the nonlinear modeling parameters of beam components for the specific type of reinforcement used in the construction of a *** updated non-linear modeling parameters of beam components in lumped plasticity model are compared with the values of ASCE/SEI 41-06(2007) used for the performance based design of structures.

关键词： concrete structures pushover loads cyclic loads hy

La^(3+) -doped SrBi_2Ta_2O_9 thin films for FRAM synthesized by sol-gel method

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Journal of Rare Earths 2014年第3期32卷 277-281页

作者： v.v.Sidsky A.v.Semchenko A.G.Rybakov v.v.Kolos A.S.Turtsevich A.N.Asadchyi W.Strek F.Skorina Gomel State University JSC ?INTEGRAL? 121A Kazintsa st. Minsk 220108 Belarus Institute of Low Temperature and Structures Research PAN Okolna st.2 Wroclaw Poland

This paper discusses the possibility of synthesis of SBTL sol-gel films for use as active layers for non-volatile memory （FRAM）. La-doped SrBi2Ta209 thin films were synthesized by sol-gel method on Pt/TiO2/BPSG/SiO2/Si substrates. The structural features of the surface （AFM）, crystallization behavior （XRD） during the heating and ferroelectric properties of synthesized films were discussed. It was shown that an optimum surface structure and a high share of perovskite phase of SBTL-films were compared to SBT-films （Theating=800 ℃）. Achieved ferroelectric parameters suggested the possibility of using synthesized SBTL sol-gel films in non-volatile memory devices.

关键词： ferroelectric thin films sol-gel method lanthanum ion non-volatile memory rare earths

A review on the current status of Fe-Al based ferritic lightweight steel

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Defence Technology（防务技术） 2023年第8期26卷 1-22页

作者： Shivkumar Khaple Brahma Raju Golla v.v.Satya Prasad Defence Metallurgical Research Laboratory HyderabadIndia Metallurgical and Materials Engineering Department National Institute of TechnologyWarangalIndia

There is an ever-growing demand for lightweighting of steel for structural applications,particularly for automobile and transportation *** is mainly to improve the fuel efficiency,reduce the CO_(2) emissions and cater the increased passenger ***,the main focus is to reduce the density of the steel structure without affecting other *** can be achieved by down-gauging of the conventional steel by replacing the steel with higher strength,however,it is limited by dent resistance and ***,the novel idea is to reduce the density of the steel *** is well-known that addition of Al to steel reduces the density of the *** 1wt% of Al addition to steel can reduce the density by 1.3%,decreases the elastic modulus by 2% and it improves the strength by about 40 *** is a new class of low-density/lightweight steel with addition of about 6-9 wt% Al to *** of higher than 9 wt%of Al in steel leads to embrittlement issues due to ordering and environmental *** disordered Fe-Al lightweight steels have raised considerable interest due to their low-density,high ductility,costeffectiveness and feasibility for bulk *** low-density steels are envisaged in the development of an advanced lightweight ground transportation system,huge structures and also for certain defence applications and in thermal power plants.

关键词： Low-density steels Disordered FeeAl Thermo-mechanical processing Microstructure Properties Structure-property correlation

A Spectral Atlas of F and G Stars

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Chinese Journal of Astronomy and Astrophysics 2004年第3期4卷 279-283页

作者： v.G.Klochkova GangZhao v.E.Panchuk S.v.Ermakov NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012 SpecialAstrophysicalObservatoryRussianAcademyofSciences NizhnijArkhyzKarachai-Cherkessia369167Russia

We present an atlas of a group of bright stars in the range of spectral classes F–G and luminosity classes I–v. The spectra were obtained with spectral resolution R ~ 15 000 within spectral region 4500–6620?. Typical spectra of stars with different metallicity [Fe/H] are included. We also show the digital version of the spectral data in FITS format.

关键词： stars: atlas stars: spectral class stars: F-G type