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Rotordynamic prediction of mode order transition when rotor has an overhang

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航空动力学报 2015年第2期30卷 397-409页

作者： konstantin Shaposhnikov HONG Jie ZHANG Da-yi MA Yan-hong School of Energy and Power Engineering Beijing University of Aeronautics and Astronautics

Nowadays rotating machinery grows and develops extremely fast due to its multi-branch *** the fields of rotordynamics and rotor balancing had a strong background based on previous experience in order to perform efficient and safe operation for the rotating machines,still there are problems which are hard to be dealt with in some special *** of them is balancing of the rotor with huge *** with overhang is inherent to have console modes,which previously often were observed separately from the other modes in rotordynamic *** such a way console modes,their behavior,order of appearance and interaction with other modes were described in current paper in more *** results confirmed that console modes obey the principle of orthogonality in the same way as all other modes and hence could be efficiently balanced using modal balancing *** results revealed likelihood of such phenomena as modes order transition,when the rotor has an *** a consequence perfectly balanced console rotor could not be so due to modes order transition effect when the bearing stiffness in situ differs from bearing stiffness of balancing *** results will be useful for engineers who are involved in area of rotating machinery vibration tuning for the rotor with huge overhang and benefit them to recognize these modes efficiently and to perform balancing successfully.

关键词：疲劳寿命分散性顺序统计量寿命分散系数小子样

Numerical study of high-lift hydrofoil near free surface at moderate Froude number

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Journal of Hydrodynamics 2020年第1期32卷 44-53页

作者： Tao Xing konstantin I.Matveev Miles P.Wheeler Department of Mechanical Engineering The University of IdahoMoscowIdahoUSA School of Mechanical and Materials Engineering Washingion State UniversityPullmanWashingtonUSA

Shallow hydrofoils are known to produce lower lift in normal operating conditions in comparison with deep ***,the maximum lift capability of shallow hydrofoils at moderate speeds,which is important for transitional regimes of hydrofoil boats,is studied *** this work,two-dimensional flow around a high-lift hydrofoil at a moderate Froude number is numerically simulated in a broad range attack angles up to the stall occurrence in both single-phase fluid and in the vicinity of free *** is found that nearly the same maximum lift coefficient can be produced by the shallow foil in the modeled condition as by the deep foil,but much higher attack angle is required near the free surface,which also results in larger ***,it is shown that higher Reynolds numbers lead to higher lift coefficients,especially at large attack angles.

关键词： Hydrofoil numerical simulation free surface effect stall

High-resolution photoacoustic microscope for rat brain imaging in vivo

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Chinese Optics Letters 2010年第6期8卷 609-611页

作者：杨孝全蔡鑫 konstantin Maslov 汪立宏骆清铭 Britton Chance Center for Biomedical Photonics Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and Technology Optical Imaging Laboratory Department of Biomedical EngineeringWashington University in Saint LouisSaint Louis63130-4899USA

A reflection-mode photoacoustic microscope（PAM） for rat brain imaging in vivo is constructed.A pulsed laser is used as an excitation source,and a focused ultrasound transducer is adopted to collect the photoacoustic *** scanning is applied to acquire three-dimensional（3D） *** obtained measurements of the lateral and axial resolutions of the microscope are 45 and 15μm,*** imaging depth in the chicken breast tissue is 3.1 mm at a signal-to-noise ratio（SNR） of 20 dB without any signal *** imaging speed is 30 A-line/*** results in vivo demonstrate the capability of 3D imaging of the brain vessels of the rat after removing the skull.

关键词： Acoustic microscopes Laser excitation Photoacoustic effect Photoacoustic microscopy Pulsed laser applications Pulsed lasers Signal to noise ratio Ultrasonic transducers

Cooling and energy loss of partially ionized hydrogen gas behind a shock wave

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Research in Astronomy and Astrophysics 2018年第8期18卷 111-116页

作者： Oksana Mikhailovna Belova konstantin Veniaminovich Bychkov Faculty of Physics Lomonosov Moscow State University Sternberg Astronomical Institute Lomonosov Moscow State University

We studied the difference in behavior of total energy and its thermal component during the radiative cooling of partially ionized hydrogen gas. Our calculations were fulfilled for the conditions in the atmosphere of a... 详细信息

关键词： stellar atmospheres shock wave

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我用我的中国20年为你庆祝

国际人才交流 2024年第1期 F0002-F0002页

作者：康斯坦丁·谢平 CGTN俄语部

2024年是国家外国专家局成立70周年。对我而言,2024年也是一个值得庆祝的年份,这是我在中国工作和生活的第20个年头。关键词之所以是“庆祝”,是因为中国已经成为我的第二故乡。时光荏苒,岁月如流。我出生在苏联城市基洛夫,在那里生活... 详细信息

2024年是国家外国专家局成立70周年。对我而言,2024年也是一个值得庆祝的年份,这是我在中国工作和生活的第20个年头。关键词之所以是“庆祝”,是因为中国已经成为我的第二故乡。时光荏苒,岁月如流。我出生在苏联城市基洛夫,在那里生活学习一直到17岁。后来到莫斯科,在莫斯科国立国际关系学院学习深造,毕业后,我到了塔斯社的俄罗斯首都总部,开始了新闻工作者的职业生涯。我在莫斯科一共度过了7年。

关键词：国家外国专家局国际关系学院新闻工作者时光荏苒基洛夫职业生涯第二故乡俄罗斯

气候对伊比利亚半岛尼安德特人向现代人人种转变的影响

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Science Bulletin 2023年第11期68卷 1176-1186,M0004页

作者： konstantin Klein Gerd-Christian Weniger Patrick Ludwig Christian Stepanek 张旭 Christian Wegener 邵亚平 Institute for Geophysics and Meteorology University of CologneCologne 50923Germany Institute of Prehistory University of CologneCologne 50923Germany Institute of Meteorology and Climate Research Karlsruhe Institute of TechnologyKarlsruhe 76131Germany Paleoclimate Dynamics Alfred Wegener InstituteHelmholtz Centre for Polar and Marine ResearchBremerhaven 27570Germany Alpine Paleoecology and Human Adaption Group State Key Laboratory of Tibetan Plateau Earth SystemChinese Academy of SciencesBeijing 100101China

伊比利亚半岛对从尼安德特人到现代人的人种转变有着特殊的意义.从东欧向西迁徙的现代人较晚才抵达伊比利亚,因此两个种群之间在这里发生任何可能接触的时间要晚于其他地方.伊比利亚半岛的人种转变发生在海洋同位素第3阶段的早期(约6万... 详细信息

伊比利亚半岛对从尼安德特人到现代人的人种转变有着特殊的意义.从东欧向西迁徙的现代人较晚才抵达伊比利亚,因此两个种群之间在这里发生任何可能接触的时间要晚于其他地方.伊比利亚半岛的人种转变发生在海洋同位素第3阶段的早期(约6万到2.7万年前),其间反复强烈的气候变化影响了种群稳定性.本文研究了气候变化和人类相互作用如何影响种群的过渡.结合气候数据与考古遗址数据重建了GI11-10(格陵兰间冰期)和GS10-9/HE4(格陵兰冰期)时期尼安德特人和现代人的生存潜力或生存概率.结果发现,由于气候变化,在GS10-9/HE4期间,伊比利亚半岛的大部分地区已不适合尼安德特人的生存.尼安德特人的定居区收缩为较为孤立的沿海热点.这可能使得尼安德特人的种群结构变得更不稳定,从而引发人口的最终崩溃.现代人大约在GI10期间抵达了伊比利亚,但仅限于半岛最北部地带的局部地区.GS10-9/HE4的寒冷气候阻止了他们的进一步扩张,甚至导致了他们定居区域的缩小.气候变化与人口迁徙使得尼安德特人和现代人两个种群的人口分散在半岛的不同区域.因此,尼安德特人和现代人在广泛的地区共存的可能性不大,而现代人对尼安德特人的最后消亡的影响也有限.

关键词：尼安德特人伊比利亚半岛数据重建气候变化影响考古遗址人口迁徙生存概率人口分散

Mechanisms of cast structure and stressed state formation in Hadfield steel

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China Foundry 2016年第6期13卷 433-442页

作者： Dmitri Gorlenko konstantin Vdovin Nikolay Feoktistov Nosov Magnitogorsk State Technical University Magnitogorsk Russia

The paper describes the investigation of mechanisms of cast structure formation in Hadfield steel depending on the changes in the cooling rate of a casting in the following two temperature ranges: crystallization temperature(1,200-1,390 °С) and the temperature of excessive phase separation(560-790 °С). Changes in the cooling rate of the crystallization temperature range from 1.1 to 25.0 °С·s^(-1) result in the reduction of the average size of austenite grains from 266 to 131 μm. At the same time, the magnitude of developing shrinkage stresses changes from +195 to 0 MPa. When the cooling rate is higher than 16 °С·s^(-1), no shrinkage stresses are formed in the casting. Changes in the cooling rate of the casting in the temperature range of the excessive phase separation influence the number of phases, their morphology and chemical composition, the values of phase stresses, and the possibility of martensitic transformation. Changing in the cooling rate from 0.24 to 5.46 °С·s^(-1) results in the decrease of the amount of the excessive phase from 14.8% to 2.1%, which is composed of eutectic and carbides depending on the cooling rate, their quantitative ratio and morphology change. Such changes in the microstructure are reflected on the changes of value of developing phase stresses. When the cooling rate is 0.24 °С·s^(-1), it is +100 MPa, while the increase of the cooling rate to 1.4 °С·s^(-1) results in the decrease of tensile stresses to 0 MPa and their qualitative stresses change to compressive ones. Further increase of the cooling rate results in the increase of the value of compressive stresses. When the cooling rate is 5.5 °С·s^(-1), their value reaches-92 MPa. Martensite forming in the structure of Hadfield steel is possible if the cooling rate of the casting in the range of excessive phase separation is less than 0.25 °С·s^(-1).

关键词： Hadfield steel crystallization austenite excessive phase stress

New family of single-component Ni catalysts for ethylene polymerization to high and ultrahigh molecular weight polyethylene

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Science China Chemistry 2020年第6期63卷 753-754页

作者： Artem A.Antonov Wen-Hua Sun konstantin P.Bryliakov Boreskov Institute of Catalysis Pr.Lavrentieva 5Novosibirsk 630090Russia Novosibirsk State University Pirogova 1Novosibirsk 630090Russia Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing 100190China CAS Research/Education Center for Excellence in Molecular Sciences University of Chinese Academy of SciencesBeijing 100049China

Since the milestone discovery of Ni(II)salicylaldiminate catalysts by Grubbs and co-workers[1],nickel(II)complexes with N,N-and N,O-donor ligands have strengthened their lead in the search for highly active platforms for olefins homo-and copolymerization with various co-monomers,including those with polar groups,to achieve polymers with precisely controlled microstructures[2,3].

关键词： discovery catalysts co-monomers

Magnetic field hyperactivity during the early Neoproterozoic: A paleomagnetic and cyclostratigraphic study of the Katav Formation, southern Urals, Russia

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Geoscience Frontiers 2023年第4期14卷 42-56页

作者： Inessa V.Golovanova konstantin N.Danukalov Raushaniia Yu.Salmanova Natalia M.Levashova Nikita P.Parfiriev Nina D.Sergeeva Joseph G.Meert Institute of Geology-Subdivision of the Ufa Federal Research Centre of the Russian Academy of Sciences(IG UFRC RAS) Russia Geological Institute Russian Academy of SciencesMoscowRussia Department of Earth and Planetary Sciences Neil Opdyke Paleomagnetic LaboratoryUniversity of FloridaGainesvilleFL 32611United States

We present a detailed magnetostratigraphic and cyclostratigraphic profile through the Riphean(Tonian)Katav Formation in the southern *** study confirms the primary nature of the magnetization in these *** cyclostratigraphic study identified several orbital periods including the 405 ka long *** allows us to quantify the reversal frequency in the Katav and our estimates range of 7–12 reversals per million *** on our study,we identify an interval of magnetic field reversal hyperactivity in the Neoproterozoic *** estimates for the Katav are contentious and range somewhere between 800 Ma and 900 Ma based on carbonate Pb-Pb ages and stable isotope *** paleomagnetic poles obtained in this study of the Katav(and overlying Inzer)Formation do not fit anywhere on the Baltica apparent polar wander path between 1100 Ma and 900 ***,they lie 90away from the 900 Ma segment of the *** tentatively estimate their age to be closer to 800 Ma and perhaps confirm a previously hypothesized pulse of rapid true polar wander between 825 Ma and 790 Ma.

关键词： Magnetostratigraphy Cyclostratigraphy Hyperactive reversal True polar wander Tonian