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Three-dimensional structure of the inner core of rice dwarf virus

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Science China(Life Sciences) 2001年第2期44卷 192-198页

作者：邵承华 Z.H.Zhou 卢光莹 National Laboratory of Protein Engineering and Plant Genetic Engineering College of Life Sciences Peking University Beijing China Department of Pathology and Laboratory Medicine Houston Medical School University of Texas Houston USA

Rice dwarf virus (RDV) is a double-shelled icosahedral virus. Using electron cryomicro-scopy and computer reconstruction techniques, we have determined a 3.3 nm resolution three-dimensional (3D) structure of the inner shell capsid without the outer shell and viral RNA. The results show that the inner shell is a thin, densely packed, smooth structure, which provides a scaffold for the full virus. A total of 120 copies of the major inner shell capsid protein P3 forms 60 dimers arranged in a T=1 icosahedral lattice. A close examination on the subunit packing of the T=1 inner core P3 with that of the T=13/ outer shell P8 indicated that P8 trimers connect with P3 through completely non-equivalent, yet highly specific, intermolecular interactions.

关键词： rice dwarf virus inner core three-dimensional structure.

The Gravity Field Variation Caused by inner core Super Rotation

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Geo-Spatial Information Science 2008年第4期11卷 283-288页

作者： CHEN Wei SHEN Wenbin HAN Jiancheng Department of Geophysics School of Geodesy and Geomatics Wuhan University 129 Luoyu Road Wuhan 430079 China

Due to the super rotation of the Earth＇s inner core, the tilted figure axis of the inner core would progress with respect to the mantle and thus cause the variation of the Earth＇s external gravity field. This paper improves the present model of the gravity field variation caused by the inner core super rotation. Under the assumption that the inner core is a stratifying ellipsoid whose density function is fitted out from PREM and the super rotation rate is 0.27-0.53°/yr, calculations show that the global temporal variations on the Earth＇s surface have a maximum value of about 0.79-1.54×10^3 pGal and a global average intensity of about 0.45-0.89×10^ 3 μGal in the whole year of 2007, which is beyond the accuracy of the present gravimetry and even the super conducting gravimeter data. However, both the gravity variations at Beijing and Wuhan vary like sine variables with maximal variations around 0.33 pGal and 0.29 pGal, respectively, in one cycle. Thus, continuous gravity measurements for one or two decades might be able to detect the differential motion of the inner core.

关键词： inner core super rotation gravity variation

First-principles calculations of high pressure and temperature properties of Fe_(7)C_(3)

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Chinese Physics B 2023年第7期32卷 625-630页

作者：范莉莉刘勋高畅刘中利李艳丽黄海军 School of Science Wuhan University of TechnologyWuhan 430070China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Eckstrom-adcock iron carbide(Fe_(7)C_(3))is considered to be the main constituent of the Earth’s inner core due to its low shear wave ***,the crystal structure of Fe_(7)C_(3)remains controversial and its thermoelastic properties are not well constrained at high temperature and *** on the first-principles simulation method,we calculate the relative phase stability,equation of state,and sound velocity of Fe_(7)C_(3)under core *** results indicate that the orthorhombic phase of Fe_(7)C_(3)is stable under the core *** Fe_(7)C_(3)does reproduce the low shear wave velocity and high Poisson’s ratio of the inner core,its compressional wave velocity and density are 12%higher and 6%lower than those observed in seismic data,***,we argue that carbon alone cannot completely explain the thermal properties of the inner core and the inclusion of other light elements may be required.

关键词： iron carbide phase stability thermoelastic properties sound velocities inner core

Development of Asymmetric Convection in a Tropical Cyclone under Environmental Uniform Flow and Vertical Wind Shear

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Advances in Atmospheric Sciences 2024年第12期41卷 2399-2418页

作者： Yubin LI Yuncong JIANG Johnny C.L.CHAN Kevin K.W.CHEUNG School of Atmospheric Physics Nanjing University of Information Science&TechnologyNanjing 210044China Asia-Pacific Typhoon Collaborative Research Center Shanghai 201306China School of Energy and Environment City University of Hong KongHong Kong 999077China School of Emergency Management Nanjing University of Information Science&TechnologyNanjing 210044China

Idealized numerical simulations have been carried out to reveal the complexity in the development of asymmetric convection in a tropical cyclone(TC)under the influence of an environment with either uniform flow,vertical wind shear(VWS),or *** show that rainwater is enhanced to the right of the motion in the outer rainband,but such enhancement occurs in the upshear-left area of the inner-core ***,due to the asymmetries introduced by environmental flow,wavenumber-1 temperature and height anomalies develop at a radius of~1000 km in the upper levels.A sub-vortex aside from the TC center encompassing the wavenumber-1 warm center appears,and asymmetric horizontal winds emerge,which,in turn,changes the storm-scale(within 400 km)*** convection in the inner core closely follows the changing storm-scale VWS when its magnitude is larger than 2 m s^(-1) and is located downshear of the storm-scale VWS in all the experiments with environmental *** the outer rainbands,the maximum boundary layer convergence is mainly controlled by the direction of motion and is located in the rear-right *** results extend upon the findings of previous studies in three aspects:(1)The discovery of the roughly linear combination effect from the uniform flow and large-scale VWS;(2)The development of upper-level asymmetric winds on a 1000-km scale through the interaction between the TC vortex and environmental flow,resulting in changes in the storm-scale VWS pattern within the TC area;(3)The revelation that TC asymmetric convection closely aligns with the direction-varying storm-scale VWS instead of the initially designated VWS.

关键词： tropical cyclone environmental flow vertical wind shear asymmetric convection inner core outer rainband

Application of Physics for Understanding the Earth’s Reverse Gravity

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Journal of Geoscience and Environment Protection 2023年第1期11卷 119-126页

作者： Subhasis Sen Retired Scientist Council of Scientific and Industrial Research Kolkata India

The prevalent view endorses that the force of gravitation of the earth is directed towards the centre of the planet, in consequence of which, temperature and pressure at the deepest part of the planet must be very high. This view leads to the conclusion that the inner core or deepest part of the planet, though constituted of iron through which magnetic lines of force emanate, cannot be magnetic. The author has shown that amongst the earth’s three geospheres, fluid outer core that occurs between mantle and inner core, is a void zone which, because of the association of some particles from the mantle, apparently shows fluid characteristics. Occurrence of a virtually void zone in the planet’s deep interior separated by a solid mantle and iron inner core would generate a reversely directed gravitational force due to which pressure and temperature at the deepest part of the earth would be sufficiently low. Hence, the earth’s solid inner core, constituted of iron, is a dipolar permanent magnet. The paper envisages that the concept of reverse gravity presented here needs to be validated by physicists since it is an original view. The concept put forward here, not only explains the cause of earth’s magnetic phenomena, but also elucidates continental drifting and several other features of the planet in a scientifically accepted manner, thereby refuting the possibility of occurrence of convection current in the mantle which is solid and rigid.

关键词： Gravitation Mantle inner core Reverse Gravity Void Zone Dipolar Permanent Magnet Meteorite

A full-sphere convection--driven dynamo:Implications for the ancient geomagnetic field

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A full-sphere convection--driven dynamo:Implications for the...