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堪察加地区现今地壳运动与变形特征研究

地球物理学报 2009年第3期52卷 720-731页

作者：孟国杰申旭辉 Vladimir Smirnov eugene a.rogozhin 伍吉仓中国地震局地震预测研究所北京100036 俄罗斯科学院地球物理研究所莫斯科123995 莫斯科大学物理系莫斯科119992 同济大学测量与国土信息工程系上海200092

利用俄罗斯堪察加地区1995～2005年的 GPS 观洲数据,研究了该区现今地壳水平运动速度场特征.在球坐标系中解算了各应变率分量,分析了应变率场的空间分布特征.并与地震学和地质学研究结果进行了综合对比分析.结果表明.堪察加半岛北部的... 详细信息

利用俄罗斯堪察加地区1995～2005年的 GPS 观洲数据,研究了该区现今地壳水平运动速度场特征.在球坐标系中解算了各应变率分量,分析了应变率场的空间分布特征.并与地震学和地质学研究结果进行了综合对比分析.结果表明.堪察加半岛北部的微板块边界并不明显.堪察加南部测站运动速度大于中部和北部地区.愈靠近东部板块汇聚区,测站速度越大.从东海岸到西海岸,测站水平速度存在明显的梯度衰减特征,水平运动方向与太平洋板块向西北的俯冲方向基本一致.各应变率分量具有东部海岸大于中部和西海岸、从东至西呈梯度衰减的特点.堪察加大部分地区处于 EW 和 NS 向压缩状念.局部存在拉张.面应变率结果显示绝大部分为压缩区;刚性转动结果表明大部分地区表现为顺时针转动,北部地区和南端顺时针旋转性明显.东部有效应变率明显大于西部地区,东西向梯度衰减关系明显.主压应变率明显大于主张应变率.特别是在东海岸地区.主压应变率方向与中等以上地震的主压应力轴在水平方向的投影方向基本一致.地壳变形场在空间分布上的不一致性主要与太平洋板块在堪察加半岛东南侧的俯冲深度、俯冲方位角、俯冲倾角和俯冲带的耦合强度有关.

关键词：堪察加地区地壳运功 GPS 应变率场

High quality large single crystals of metal halide perovskites for optoelectronic applications

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Science China Chemistry 2017年第10期60卷 1326-1327页

作者： eugene A.Katz Alexandre Yersin Department of Solar Energy and Environmental Physics J. Blaustein Institutes for Desert Research Ben-Gurion University of the Negev Sede Boqer Campus 8499000 Israel Ilse-Katz Institute for Nanoscale Science and Technology Ben-Gurion University of the Negev Beer Sheva 8410501 lsrael

As the technological development of large single-crystalline wafers have revolutionized many industries including electronics and photovoltaics,one can predict that the availability of large single-crystalline perovskite crystals and wafers can revolutionize its broad applications in photodetectors,solar cells,LEDs,lasers,*** 2015,Liu et al.

关键词： crystalline halide perovskite technological electronics inverse optoelectronic wafer availability render

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GPS揭示的贝加尔湖地区现今地壳形变特征

大地测量与地球动力学 2006年第1期26卷 15-20页

作者：孟国杰申旭辉伍吉仓任金卫 eugene a.rogozhin 同济大学测量与国土信息工程系上海200092 中国地震局地震预测研究所北京100036 俄罗斯科学院大地物理研究所莫斯科12395

利用贝加尔湖地区GPS监测网测站坐标,根据边长尽量相等的原则,形成了11个Delaunay三角形,计算了各三角形的形状因子,结果表明有9个三角形的形状因子大于0.1。利用3期GPS观测结果,通过对位移速率和应变分量的分析,初步得到以下基本认识... 详细信息

利用贝加尔湖地区GPS监测网测站坐标,根据边长尽量相等的原则,形成了11个Delaunay三角形,计算了各三角形的形状因子,结果表明有9个三角形的形状因子大于0.1。利用3期GPS观测结果,通过对位移速率和应变分量的分析,初步得到以下基本认识贝加尔湖地区目前整体上处于拉张状态,拉张速度约为4.5±1.2mm/a,拉张方向为NW-SE方向;地壳应变是不均匀的,应变分量存在区域上的差异性。东部和西部主张应变均为NW向,但主压应变方向表现不一致,监测网东西两端的应变大于中部地区,最大应变为5.4×10-8,最小应变为-2.6×10-8。贝加尔湖东南部地壳处于压缩状态,压缩方向为NNW向和NNE向;东西部剪切应变比中部大,东西部剪切应变方向基本一致,表现为近南北向;7个三角形的面应变计算结果显示地壳为膨胀状态,2个三角形显示为压缩状态。大地转动结果表明,东北部表现为顺时针的旋转,而西部地区和中部显示为逆时针的旋转。GPS揭示的应变结果与地质和地震学结果基本一致。

关键词： GPS 贝尔加湖地壳形变应变大地转动

Alternative kind of hydrogen atoms as a possible explanation for the latest puzzling observation of the 21 cm radio line from the early Universe

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Research in Astronomy and Astrophysics 2020年第7期20卷 172-176页

作者： eugene Oks Physics Department 380 Duncan DriveAuburn UniversityAuburnAL 36849USA

There is a puzzling astrophysical result concerning the latest observation of the absorption profile of the redshifted radio line 21 cm from the early Universe(as described in Bowman et al.). The amplitude of the profile was more than a factor of two greater than the largest predictions. This could mean that the primordial hydrogen gas was much cooler than expected. Some explanations in the literature suggested a possible cooling of baryons either by unspecified dark matter particles or by some exotic dark matter particles with a charge a million times smaller than the electron charge. Other explanations required an additional radio background. In the present paper, we entertain a possible different explanation for the above puzzling observational result: the explanation is based on the alternative kind of hydrogen atoms(AKHA),whose existence was previously demonstrated theoretically, as well as by the analysis of atomic experiments. Namely, the AKHA are expected to decouple from the cosmic microwave background(CMB) much earlier(in the course of the Universe expansion) than usual hydrogen atoms, so that the AKHA temperature is significantly lower than that of usual hydrogen atoms. This seems to lower the excitation(spin) temperature of the hyperfine doublet(responsible for the 21 cm line) sufficiently enough for explaining the above puzzling observational result. This possible explanation appears to be more specific and natural than the previous possible explanations. Further observational studies of the redshifted 21 cm radio line from the early Universe could help to verify which explanation is the most relevant.

关键词： Cosmology:Early Universe explanation of the puzzle of 21cm radio line Galaxies:intergalactic medium Cosmology:observations Cosmology:theory

Galactic Dark Matter Halos Containing H Ⅰ Regions:A Possible Overestimation of the Column Densities

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Research in Astronomy and Astrophysics 2023年第3期23卷 100-103页

作者： eugene Oks Physics Department Auburn UniversityAuburnAL 36849USA

We analyze how the column density of hydrogen atoms in the HⅠregions,observed in dark matter halos of a number of galaxies,can be *** we study how the determination of the column density of hydrogen atoms from the observed astrophysical data would be affected by the possible presence of the Second Flavor of Hydrogen Atoms(SFHA),whose existence had been previously demonstrated in four different types of atomic experiments and had helped in explaining two puzzling astrophysical observations:the anomalous absorption in the 21 cm line from the early Universe and the smoother,less clumpy distribution of dark matter in the Universe than predicted by Einstein’s *** a model example we demonstrate that the neglect of the SFHA leads to the overestimation of the column density of hydrogen atoms in dark matter halos by about 30%.We perform these relatively simple estimates just to get the message across and to motivate further corresponding theoretical and experimental studies.

关键词： galaxies anomalous estimation

DES map shows a smoother distribution of matter than expected:a possible explanation

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Research in Astronomy and Astrophysics 2021年第10期21卷 1-4页

作者： eugene Oks Physics Department 380 Duncan DriveAuburn UniversityAuburnAL 36849USA

The largest and most detailed map of the distribution of dark matter in the Universe has been recently created by the Dark Energy Survey(DES)*** distribution was found to be slightly(by a few percent)smoother and less clumpy than predicted by general *** result was considered as a hint of some new physical *** the present paper we offer a relatively simple model that could explain the above result without resorting to any new physical *** model deals with the dynamics of a system consisting of a large number of gravitating neutral particles,whose mass is equal to the mass of hydrogen *** central point of the model is a partial inhibition of the gravitation for a relatively small subsystem of the entire *** would be sufficient for this subsystem to constitute just about a few percent of the total ensemble of particles for explaining the few percent more smooth distribution of dark matter(observed by the DES team)compared to the prediction of general *** most viable candidate for the dark matter particles in this model is the second flavor of hydrogen atoms(SFHA)that has only S-states and therefore does not couple to the electric dipole radiation or even to higher multipole radiation,so that the SFHA is practically *** SFHA has experimental confirmation from atomic experiments,it does not go beyond the Standard Model,it is based on standard quantum mechanics and it explains puzzling astrophysical observations of the redshifted line 21 cm from the early ***,our model explaining the DES result of a little too smooth distribution of dark matter without resorting to any new physical laws seems to be self-consistent.

关键词： (cosmology:)dark matter gravitation atomic processes astroparticle physics

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东北地区现今地壳形变特征研究

大地测量与地球动力学 2007年第1期27卷 19-23页

作者：孟国杰申旭辉伍吉仓任金卫 eugene a.rogozhin 中国地震局地震预测研究所北京100036 同济大学测量与国土信息工程系上海200092 俄罗斯科学院大地物理研究所莫斯科123995

利用东北地区37个GPS测站1997～2005年的观测数据研究了该区现今地壳形变特征。结果显示：东北地区相对欧亚板块的位移速率矢量较小，平均为1．58mm／a，表明该区总体上比较稳定；有5个测站的水平位移速率在95％的置信水平上具有显著性... 详细信息

利用东北地区37个GPS测站1997～2005年的观测数据研究了该区现今地壳形变特征。结果显示：东北地区相对欧亚板块的位移速率矢量较小，平均为1．58mm／a，表明该区总体上比较稳定；有5个测站的水平位移速率在95％的置信水平上具有显著性，而其他测站则并不显著；辽西地区的几个测站显示出一致性的东南运动，可能是青藏高原东向运动的远程效应；靠近1999年Mw7．1和2002年Mw7．3深源地震震中的测站速率较小，说明这两次深源地震对地表造成的形变并不明显。黑龙江东北部测站运动可能反映了北美板块向南楔入对欧亚板块的影响。

关键词：东北地区 GPS 地壳形变欧亚板块水平位移速率

Reminiscing my sixty year pursuit of the physics of the Sun and the Galaxy

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Research in Astronomy and Astrophysics 2014年第1期14卷 1-14页

作者： eugene N.Parker Department of Physics Department of Astronomy and AstrophysicsUniversity of Chicago

Reminiscing begins with childhood and passes on to student days through graduate school and the first real contact with research. Then early academic posi- tions and stumbling efforts to pursue my ideas. The first significant progress came as a research associate with Prof. W. M. Elsasser at the University of Utah, beginning with an introduction to magnetohydrodynarnics and the generation of the geomagnetic field through induction in the liquid metal core of Earth. A move to the University of Chicago to work with Prof. J. A. Simpson, on the implications of cosmic ray varia- tions and interplanetary magnetic fields, led to the theory of coronal expansion and the solar wind and then to exploring the dynamical effects of cosmic rays on the galactic magnetic field. Spontaneous current sheets and intrinsic rapid reconnection in interlaced magnetic field line topologies were the next big project, leading up to retirement. Finally, it is a pleasure to recall my many associates, whose fresh thinking helped stimulate the daily research activities.

关键词： dynamo -- magnetohydrodynamics -- plasma

A practical geometrical comparison between free-repelled hydraulic jumps within inclined channels

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Science China(Technological Sciences) 2009年第11期52卷 3363-3367页

作者： John Demetriou eugene Retsinis National Technical University of Athens School of Civil Engineering. JD Research Hydrolab-A non Profit Foundation 12 Polykarpou St. N. Smymi Athens 17123 Greece National Technical University of Athens School of Civil Engineering. 23 Loid Tzortz St. Athens 11744 Greece

In this experimental study a practical geometrical comparison between inclined (angle φ) free and repelled hydraulic jumps (the latter in non prismatic but abruptly expanding channels) is presented, analysed and discussed. For repelled hydraulic jumps a considerable parameter is the expansion ratio r (=channels' width ratio), which here is changing from r =0.5 to r =0.7. The comparison is made with the free jump (in prismatic channel, r =1), in the same ranges of angles φ (0°≤φ≤8°) and Froude numbers (2≤Fr1≤8). A practical arithmetic example is presented to show the behavioral change of conjugate depths, lengths L and depths at 0.5L, in order to receive a comparison among all pertinent geometrical quantities. The present results may be useful for the hydraulic engineering when designing open channels.

关键词： free jumps repelled jumps inclined channels