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Stability of Macroscopic Binary Systems

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Communications in Theoretical Physics 2019年第11期71卷 1335-1340页

作者： G.G.Adamian n.V.Antonenko H.Lenske V.V.Sargsyan Joint Institu te for nuclear Research 141980 DubnaRussia Ins titut fur Theore tische Physik der Jus tus-Liebig—Uni versit nt D-35392 GiessenGermany

The Darwin instability effect in the binary systems(di-planets, di-stars, and di-galaxies) is analyzed within the model based on the Regge-like laws. All possible binary stars are found satisfying the Darwin instability condition that requires to search for other mechanism triggering the merger of the contact binary objects. new analytical formulas are obtained for the orbital rotation period and the relative distance between components of the binary system. The decreasing and increasing periods as functions of mass asymmetry are related, respectively, with the non-overlapping and overlapping stage of the binary object evolution.

关键词： Regge laws binary stars and galaxies Darwin instability effect

Morphological parameters and genetic diversity of progenies from seed production areas and unimproved stands of teak(Tectona grandis L.f.)in India

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Journal of Forestry Research 2013年第4期24卷 653-658页

作者： n.Lyngdoh Geeta Joshi G.Ravikanth R.Vasudeva R.Uma Shaanker Tree Improvement and Propagation Division Institute of Wood Sciences and Technology 18th Cross MalleswaramBangalore School of Ecology and Conservation University of Agricultural Sciences Banga- lore 560065India Ashoka Trust for Research in Ecology and the Environment Royal Enclave SrirampuraJakkur PostBangalore- 560064India Department of Forest Biology and Tree Improvement College of Forestry Sirsi581401KarnatakaIndia Department of Crop Physiology University of Agricultural Sciences Bangalore 560065India

We compared morphological and genetic attributes of prog- eny obtained from three seed production areas （SPAs） and three corre- sponding unimproved stands （UIS） of teak （Tectona grandis L.f） at three broad teak growing regions in the state of Karnataka, India. In general, seed morphological parameters such as seed weight, seed size and seed emptiness were significantly superior in SPAs compared to UISs. Seed germination percentage was also higher in seeds from SPAs. Seedling performance measured at two monthly intervals for six months was ob- served to be superior in SPAs at two of the three regions compared. Although the genetic diversity of progeny of SPAs was lower than UIS at all regions, the values were moderately high. Germination percent was positively correlated with fruit weight and kernel weight per seed, while diversity indices were negatively correlated with fruit weight, fruit di- ameter and kernel weight per seed. SPAs proved important as a source of moderately improved planting material with no severe threat to the ge- netic diversity of future plantations.

关键词： ISSR tree improvement Shannon index teak plantations percent polymorphism

nUMERICAL AnALYSIS OF HEAT TRAnSFER DURInG LASER CLADDInG TO SYnTHESIZE TiCp/Al COMPOSITE

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Acta Metallurgica Sinica(English Letters) 2004年第1期17卷 1-6页

作者： D.n.Zou J.Yang Y.L.Huang J.Y.Su School of Metallurgical Engineering Xi'an University of Architecture and Technology Xi'an 710055ChinaSchool of Metallurgical EngineeringXi'an University of Architecture and Technology Xi'an 710055ChinaSchool of Materials Science and Engineering Xi'an Jiaotong University Xi'an 710049 ChinaSchool of Materials Science and Engineering Xi'an Jiaotong University Xi'an 710049 China

Based on the continuum model for binary solid-liquid phase change system, the math-ematic model to simulate the process of laser cladding in situ synthesis TiCp/Al composite on the surface of aluminum alloy was formulated. The additive source method was employed to treat with the heat release of synthetic reaction in powder mixture at certain temperatures, and also to solve the momentum and heat transfer caused by the relative movement between laser beam and the specimen. Two different types of driving forces for flow were considered in the model, i.e., the buoyancy force and the surface tension gradient at the laser pool surface. The three-dimensional transient temperature field simulation program was developed being based upon the commercial software PHOEnICS. The calculated and observed fusion boundaries were compared and very good agreement was obtained.

关键词： numerical simulation heat transfer laser cladding in situ synthesis composite

Cordierite-bearing granulites from Ihosy,southern Madagascar:Petrology,geochronology and regional correlation of suture zones in Madagascar and India

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Geoscience Frontiers 2019年第6期10卷 2007-2019页

作者： Li Tang Meng Pan Toshiaki Tsunogae Yusuke Takamura Yukiyasu Tsutsumi n.O.T.Rakotonandrasana School of Earth Sciences and Resources China University of Geosciences Beijing29 Xueyuan RoadBeijing100083China Graduate School of Life and Environmental Sciences University of TsukubaIbaraki305-8572Japan Department of Geology University of JohannesburgAuckland Park2006South Africa Department of Geology and Paleontology National Museum of Nature and ScienceIbaraki305-0005Japan Yokohama national University Yokohama240-8501Japan

Madagascar,a major fragment of Gondwana,is mainly composed of Precambrian basenent rocks formed by Mesoarchean to neoproterozoic tectono-thernial events and recording a Pan-African metamorphic *** Ranotsara Shear Zone in southern Madagascar has been correlated with shear zones in southern India and eastern Africa in the reconstruction of the Gondwana *** we present detailed petrology,mineral chemistry,metamorphic P-T constraints using phase equilibrium modelling and zircon U-Pb geochronological data on high-grade metamorphic rocks from Ihosy within the Ranotsara Shear ***-cordierite gneiss from Ihosy experienced two stages of *** peak mineral assemblage is interpreted as garnet+sillimanite+cordierite+quartz+plagioclase+Kfeldspar+magnetite+spinel+ilmenite,which is overprinted by a retrograde mineral assemblage of biotite+garnet+cordierite+quartz+plagioclase+K-feldspar+magnetite+spinel+*** equilibria nodelling in the system na2 O-CaO-K2 O-FeO-MgO-Al2 O3-SiO2-H2 O-TiO2-Fe2 O3(nCKFMASHTO)indicates peak metamorphic conditions of 850-960℃ and 6.9-77 kbar,and retrograde P-Tconditions ofndne a clockwise P-T ***-concordant ages of detrital zircon grains in the garnet-cordierite gneiss dominantly exhibit ages between 2030 Ma and 1784 Ma,indicating dominantly Paleoproterozoic *** lower intercept age of 514±33 Ma probably indicates the timing of high-grade metamorphism,which coincides with the assembly of the Gondwana *** comparable rock types,zircon ages and metamorphic P-T paths between the Ranotsara Shear Zone and the Achankovil Suture Zone in southern India support an interpretation that the Ranotsara Shear Zone is a continuation of the Achankovil Suture Zone.

关键词： Pseudosection modelling Cordierite-bearing granulite Detrital zircon geochronology Madagascar Gondwana supercontinent

Flash sintering incubation kinetics

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npj Computational Materials 2020年第1期6卷 850-857页

作者： K.S.n.Vikrant Han Wang Aniruddha Jana Haiyan Wang R.Edwin García School of Materials Engineering Purdue UniversityWest LafayetteIN 47907USA School of Electrical and Computer Engineering Purdue UniversityWest LafayetteIN 47907USA

The microstructural mechanisms leading to onset of the flash sintering are demonstrated experimentally and theoretically for Yttria Stabilized Zirconia,*** regimes leading to flash event are identified:(1)Radiation-dominated regime,where the oven controls the heating of the sintered sample,and a small subset of particle-particle contacts and surfaces of the green body define percolative paths for the charge to flow along and across the interfaces;(2)Transition regime,where charge transport is suppressed across particle contact misorientations and deflects to surficial and small angle particle contact *** a result,internal Joule heating takes over externally-driven radiation ***,(3)Percolative regime,where the concentration of oxygen vacancies drastically increases at particle contacts,surfaces,and triple junctions,and enables charge to flow through multiple paths,generating large amounts of Joule heating,resulting in the onset of a flash *** validated theory sets the stage to rationalize the microstructural evolution and charge transport on a ceramic green body during flash sintering.

关键词： flash Flash regime

Modifi cation of sleep architecture in an animal model of experimental cirrhosis

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World Journal of Gastroenterology 2009年第41期15卷 5176-5180页

作者： Anabel Jiménez-Anguiano Vanessa Díaz-Medina Blanca Eugenia Farfán-Labonne Gloria Giono-Chiang David Kersenobich Mario García-Lorenzana Maria Concepción Gutiérrez-Ruiz Javier Velázquez-Moctezuma Area of neuroscience Department of Biology of Reproduction Universidad Autónoma Metropolitana-Iztapalapa CP 09340 Mexico City Mexico Cell Physiology Laboratory Department of Health Sciences Universidad Autónoma Metro-politana-Iztapalapa CP 09340 Mexico City Mexico Unit of Liver Pancreas and Motility Faculty of Medicine Universidad Nacional Autónoma de México Mexico City D.F CP 09340 Mexico

AIM: To analyze the polygraphic sleep patterns during cirrhosis progression in a rat model by repeated CCl4 administration. METHODS: Male Wistar rats received three weekly injections of CCl4 for 11 wk, and were analyzed before and during the induction of cirrhosis. Rats were implanted with electrodes to record their sleep patterns. Polygraph recordings were made weekly over 11 wk for 8 h, during the light period. After a basal recording, rats received three weekly injections of CCl4. Histological conf irmation of cirrhosis was performed after 11 ***: The results showed a progressive decrease in total wake time that reached statistical signif icance from the second week of treatment. In addition, there was an increase in total time of slow wave sleep (SWS) and rapid eye movement sleep (REM sleep) in most of the 11 wk. SWS showed no signif icant *** the final weeks, a significant increase in REM sleep frequency was also observed. Histological analyses of the livers showed unequivocal signs of cirrhosis. COnCLUSIOn: These data suggest that hepatic failure produced by CCl4 administration is capable of modifying the sleep pattern even after only a few doses.

关键词：睡眠模式肝硬化动物模型结构改造实验性 Wistar大鼠慢波睡眠大鼠模型

Peristaltic flow of MHD Jeffrey fluid through finite length cylindrical tube

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Applied Mathematics and Mechanics(English Edition) 2011年第10期32卷 1231-1244页

作者： D.TRIPATHI n.ALI T.HAYAT M.K.CHAUBE A.A.HEnDI Birla Institute of Technology and Science Pilani Hyderabad CampusHyderabad 500078India Department of Mathematics and Statistics International Islamic UniversityIslamabad 46000Pakistan Department of Mathematics Quaid-i-Azam UniversityIslamabad 45320Pakistan Department of Physics Faculty of ScienceKing Saud UniversityP.O.Box 1846Riyadh 11320Saudi Arabia Department of Applied Mathematics IT-BHUVaranasi 221005India

The present investigation studies the peristaltic flow of the Jeffrey fluid through a tube of finite length. The fluid is electrically conducting in the presence of an applied magnetic field. Analysis is carried out under the assumption of long wavelength and low Reynolds number approximations. Expressions of the pressure gradient, volume flow rate, average volume flow rate, and local wall shear stress are obtained. The effects of relaxation time, retardation time, Hartman number on pressure, local wall shear stress, and mechanical efficiency of peristaltic pump are studied. The reflux phenomenon is also investigated. The case of propagation of a non-integral number of waves along the tube walls, which are inherent characteristics of finite length vessels, is also examined.

关键词： peristaltic flow magnetohydrodynamics Jeffrey fluid finite length tube mechanical efficiency reflux

The Study of the Secrets of the Genetic Code

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Journal of Computer and Communications 2018年第7期6卷 64-83页

作者： n. n Kozlov Keldysh Institute of Applied Mathematics of Russian Academy of Sciences Moscow Russia

The disclosure of many secrets of the genetic code was facilitated by the fact that it was carried out on the basis of mathematical analysis of experimental data: the diversity of genes, their structures and genetic codes. new properties of the genetic code are presented and its most important integral characteristics are established. Two groups of such characteristics were distinguished. The first group refers to the integral characteristics for the areas of DnA, where genes are broken down in pairs and all 5 cases of overlap, allowed by the structure of DnA, were investigated. The second group of characteristics refers to the most extended areas of DnA in which there is no genetic overlap. The interrelation of the established integral characteristics in these groups is shown. As a result, a number of previously unknown effects were discovered. It was possible to establish two functions in which all the over-understood codons in mitochondrial genetic codes (human and other organizations) participate, as well as a significant difference in the integral characteristics of such codes compared to the standard code. Other properties of the structure of the genetic code following from the obtained results are also established. The obtained results allowed us to set and solve one of the new breakthrough problems—the calculation of the genetic code. The full version of the solution to this problem was published in this journal in August 2017.

关键词： Genetic Code Overlapping Genes Degeneracy Code Code Irregularities Potential Code for Overlaps Common Property Codes Integral Characteristics Code Deviation Code Elementary Overlaps Role-Reinterpreted Codons Code Is not Arbitrary

Analytical and simulation studies for diode and triode ion beam extraction systems

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Chinese Physics C 2012年第4期36卷 344-349页

作者： M. M. Abdelrahman n. I. Basal S. G. Zakhary Accelerators & Ion Sources Department Nuclear Research Center Atomic Energy Authority P.O. Box: 13759 Inchas Atomic Energy Authority

This work is concerned with ion beam dynamics and compares the emittance to aberration ratios of two-and three-electrode extraction systems. The study is conducted with the aid of Version 7 of SIMIOn 3D ray-tracing software. The beam dependence on various parameters of the extraction systems is studied and the numerical results lead to qualitative conclusions. Ion beam characteristics using diode and triode extraction systems are investigated with the aid of the computer code SIMIOn 3 D, Version 7.0. The diode （two electrode extraction system） and triode （three- electrode extraction, acceleration-deceleration system） extraction systems are designed and optimized with different geometric parameters of the electrode system, voltage applied to the extraction electrode, and plasma parameters inside the ion source chamber, as well as by the ion beam space charge. This work attempts to describe the importance of the acceleration-deceleration extraction system. It shows that besides an increase of the beam energy, the ion beam has lower emittance than the two-electrode extraction system. Ion beams of the highest quality are extracted whenever the half-angular divergence is minimum for which the perveance current intensity and the extraction gap have optimum value. Knowing the electron temperature of the plasma is necessary to determine plasma potential and the exact beam energy.

关键词： ion beam emittance plasma meniscus space charge ion beam SIMIOn computer program