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Acta Geologica Sinica(english edition) 2016年第S1期90卷 118-119页

作者： Samsonov A.V. Stepanova A.V. Salnikova e.b. Larionova Yu.O. egorova S.V. Larionov A.N. IGeM RAS IG Kar RC RAS IPGG RAS VSeGeI

Mafic dykes preserved important information on mantle melting regimes in the early earth *** the fact that a large volume of geochronological data for mafic dykes was recently received,several important issues

关键词： Pb U-Pb baddeleyite/Zircon Geochronology and Sr-Nd Isotopic Data Nd Sr Ga

Investigating dynamic mechanisms of geological phenomena using methodology of computational geosciences:An example of equal-distant mineralization in a fault

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Science China earth Sciences 2008年第7期51卷 947-954页

作者： b.e.HObbS A.ORD CSIRO Division of exploration and Mining P. O. Box 1130 Bentley WA 6102 Australia

This paper presents a research methodology associated with approximately a decade old computa- tional geosciences. To demonstrate how it can be used to investigate the dynamic mechanisms of geological phenomenon, we use as an example the equal-distant distribution of gold deposits in a three-dimensional perme.b.e fault within the Yilgarn Craton, Western Australia. The related numerical results demonstrate that: (1) convective pore-fluid flow in fluid-saturated porous media is the control- ling dynamic mechanism leading to the equal-distant distribution of gold deposits along the fault; (2) the main characteristic of the new methodology is to change the traditionally used empirical, descrip- tive and qualitative methodology into the fundamentally scientific principles based predictive and quantitative methodology. Thus, this new methodology provides a modern scientific research tool for investigating the dynamic mechanisms associated with observed geological phenomena in nature.

关键词： computational geosciences research methodology geological phenomena dynamic mechanisms

On Nonlinear Rayleigh-Taylor Instabilities

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Acta Mathematica Sinica,english Series 2006年第4期22卷 1007-1016页

作者： b.DeSJARDINS e.GReNIeR CeA/DIF b.P.12 91680 Bruyères le ChatelFrance U.M.P.A.C.N.R.S.U.M.R.5669 Ecole Normale Supérieure de Lyon69364 Lyon cedex 7France

Some of the mathematical properties of the interface.b.tween two incompressible inviscid and immiscible fluids with different densities under the influence of a constant gravity field 9 are investigated. The purpose of this paper is to prove that linearly unstable modes for Rayleigh-Taylor instabilities give.b.rth to nonlinear instabilities for the full nonlinear system. The main ingredient is a general instability theorem in an analytic framework which enables us to go from linear to nonlinear instabilities.

关键词： Fluid Mechanics Instability Nonlinear Spectrum Analytic regularity

Audio-frequency heating of particulate magnetic systems

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China Particuology 2007年第1期5卷 84-92页

作者： b.e. Kashevsky I.V. Prokhorov S.b. Kashevsky A.V. Luikov Heat and Mass Transfer Institute Belarus Academy of Sciences P. Brovka str. 15 Minsk 220072 Belarus

This paper presents theoretical and experimental studies on the magnetodynamics and energy dissipation in suspensions of small ferromagnetic particles with magnetic hysteresis and mechanical mobility in an AC magnetic field. energy absorption by particles suspended in a solid, liquid or gas environment and subjected to high frequency magnetic fields is of great interest for cancer treatment by hyperthermia, chemical technology, biotechnology and smart materials science. Sub-micron needle-like γ-Fe2O3 particles dispersed in liquid were subjected in this study to a 430 Hz magnetic field with an intensity of up to 10^5 A/m. Dynamic magnetization loops were measured in parallel to the energy dissipated in the samples. Combined magnetomechanical dynamics of particle dispersions was simulated by using a chain-of-spheres model allowing for incoherent magnetic field reversal. In liquid dispersions, within the kilohertz frequency range, the mechanical mobility of particles does not interfere with their hysteretic magnetic reversal that makes heat release comparable to that observed with solids; for instance, in the present study using γ-Fe2O3 particles in liquid subjected to 10^4 Hz field exhibited heat release rates from 250 up to 600W oer 1 cm^3 of the dry oarticle content.

关键词： AC magnetic field Particulate materials Audio-frequency heating

A comprehensive study for mass attenuation coefficients of different parts of the human body through Monte Carlo methods

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Nuclear Science and Techniques 2016年第3期27卷 31-39页

作者： e.e.ermis F.b.Pilicer e.Pilicer C.Celiktas Physics Department Faculty of ScienceEge University Physics Department Faculty of Arts and ScienceUludag University

The gamma-ray mass attenuation coefficients of blood,bone,lung,eye lens,adipose,tissue,muscle.b.ain and skin were calculated at different energies(60,80,150,400,500,600,1000,1250,1500,and 2000 keV) by various theoretical methods such as FLUKA,GeANT4 Monte Carlo(MC) methods and XCOM program in this *** coefficients were also compared with the National Institute of Standards and Technology(NIST) *** results were highly in accordance with each other and NIST *** results showed that FLUKA was quite convenient in comparison to GeANT4 in the calculation of the mass attenuation coefficients of the used human body samples for low-energy photons(60,80,and 150 keV) when compared with the NIST values.

关键词：质量衰减系数蒙特卡洛方法 Geant4 部位 NIST 美国国家标准能量计算眼晶状体

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夏洛的网

语数外学习(高中版下旬) 2018年第6期 84-91页

作者： e.b.怀特

《夏洛的网》的作者是e.b.怀特(***),是一部可以与《小王子》相媲美的世界名著,这部作品初版于1952年,至今已有20多种译文,发行近千万册。《夏洛的网》是一部描写友情的童话。在朱克曼家的谷仓里,小猪威尔伯和蜘蛛夏洛建立了最真挚的友... 详细信息

《夏洛的网》的作者是e.b.怀特(***),是一部可以与《小王子》相媲美的世界名著,这部作品初版于1952年,至今已有20多种译文,发行近千万册。《夏洛的网》是一部描写友情的童话。在朱克曼家的谷仓里,小猪威尔伯和蜘蛛夏洛建立了最真挚的友谊。威尔伯的生命有危险时,看似渺小的夏洛用自己的力量救了威尔伯,但,这时,蜘蛛夏洛的生命却走到了尽头……作者用童话的叙事风格表现出一份对生命本身的赞美与眷恋,给了我们关于生命的深沉的思索。本文节选自《夏洛的网》第三章。

关键词：祖克曼

Chemical forms and extractability of iron in sediments of three contrasting lakes of China and UK

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Journal of environmental Sciences 2003年第6期15卷 728-733页

作者： Gibson C.e.,Stewart b.M. Key Laboratory of Terrestrial ecological Process Institute of Applied ecology Chinese Academy of Sciences Department of Agricultural and environmental Science Queen's University belfast Shenyang 110016 China Newforge Lane belfast bT9 5PX UK

Iron is a limiting factor for the eutrophication of lakes, especially those lakes that are enriched with phosphorus. extractability of iron in sediments of West Lake and Taihu Lake in China and Lower Lough erne in Northern Ireland of UK was comparatively investigated on the.b.sis of analysing chemical forms of iron using different extractants. It was shown that extractable iron in sediments of the lakes was greatly different using various extractants. Reactive iron or easily released iron such as “active" iron oxides, total free iron oxide and water-soluble iron was not high, only accounting for 0.01%—0.15% of total iron. The efficiency of the extractants for exchange.b.e iron was decreased in the sequence 0.1 mol/L HCl DTPA+TeA mixed solution > 1 mol/L NH 4OAc > 0.5 mol/L MgCl 2 = 0.5 mol/L CaCl 2. It seems that the complexion of iron by organic matter was not strong because the concentration of organically bound iron was significantly lower than the concentration it was forecasted. extractable iron is not entirely consistent with or dependent on total iron in lake sediments. To a certain extent, phosphate can inhibit the release of iron in sediments of the lakes. The selection of extractants is thus the first key step to evaluate.b.oavailability of iron in lake sediments.

关键词： iron chemical form extractability lake sediment eutrophication

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地质专辑第2辑第四纪地质

地质专辑第2辑第四纪地质

Impurity effects on electrical conductivity of doped bilayer graphene in the presence of a bias voltage

1956年

作者： e.b.善采尔等余兆吴光输等译

来源：汇雅图书（南通市图书馆... 评论

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Chinese Physics b 2016年第7期25卷 316-323页

作者： e Lotfi H Rezania b Arghavaninia M Yarmohammadi Department of Physics Sanandaj Branch Islamic Azad University Department of Physics Razi University Department of Physics Kermanshah Branch Islamic Azad University Young researchers and elite Club Kermanshah Branch Islamic Azad University

We address the electrical conductivity of bilayer graphene as a function of temperature, impurity concentration, and scattering strength in the presence of a finite.b.as voltage at finite doping, beginning with a description of the tight-binding model using the linear response theory and Green＇s function approach. Our results show a linear behavior at high doping for the case of high bias voltage. The effects of electron doping on the electrical conductivity have.b.en studied via changing the electronic chemical potential. We also discuss and analyze how the.b.as voltage affects the temperature.b.havior of the electrical conductivity. Finally, we study the.b.havior of the electrical conductivity as a function of the impurity concentration and scattering strength for different bias voltages and chemical potentials respectively. The electrical conductivity is found to be monotonically decreasing with impurity scattering strength due to the increased scattering among electrons at higher impurity scattering strength.

关键词： bilayer graphene Green's function electrical conductivity

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夏洛的网(节选)

语数外学习(初中版中旬) 2008年第Z1期 74-79页

作者： e.b.怀特

一头名叫威尔伯的小猪和一只叫夏洛的蜘蛛成了朋友。小猪未来的命运是成为圣诞节的盘中大餐。威尔伯试过逃跑,但它只是一只猪。看似渺小的夏洛说:"让我来帮你。"于是夏洛用它的网在猪栏中织出"好猪""杰出""谦虚"等字样,那些被人类视为... 详细信息

一头名叫威尔伯的小猪和一只叫夏洛的蜘蛛成了朋友。小猪未来的命运是成为圣诞节的盘中大餐。威尔伯试过逃跑,但它只是一只猪。看似渺小的夏洛说:"让我来帮你。"于是夏洛用它的网在猪栏中织出"好猪""杰出""谦虚"等字样,那些被人类视为奇迹的字样让威尔伯的命运逆转,终于得到了一个安享天命的未来。但在这时,蜘蛛夏洛的生命却走到了尽头……

关键词：威尔伯夏洛的网