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Major Modes of Short-Term Climate Variability in the Newly Developed NUIST Earth System Model(NESM) 被引量:10
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作者 CAO Jian Bin WANG +5 位作者 Baoqiang XIANG Juan LI WU Tianjie Xiouhua FU WU Liguang MIN Jinzhong 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第5期585-600,共16页
A coupled earth system model(ESM) has been developed at the Nanjing University of Information Science and Technology(NUIST) by using version 5.3 of the European Centre Hamburg Model(ECHAM), version 3.4 of the Nu... A coupled earth system model(ESM) has been developed at the Nanjing University of Information Science and Technology(NUIST) by using version 5.3 of the European Centre Hamburg Model(ECHAM), version 3.4 of the Nucleus for European Modelling of the Ocean(NEMO), and version 4.1 of the Los Alamos sea ice model(CICE). The model is referred to as NUIST ESM1(NESM1). Comprehensive and quantitative metrics are used to assess the model's major modes of climate variability most relevant to subseasonal-to-interannual climate prediction. The model's assessment is placed in a multi-model framework. The model yields a realistic annual mean and annual cycle of equatorial SST, and a reasonably realistic precipitation climatology, but has difficulty in capturing the spring–fall asymmetry and monsoon precipitation domains. The ENSO mode is reproduced well with respect to its spatial structure, power spectrum, phase locking to the annual cycle, and spatial structures of the central Pacific(CP)-ENSO and eastern Pacific(EP)-ENSO; however, the equatorial SST variability,biennial component of ENSO, and the amplitude of CP-ENSO are overestimated. The model captures realistic intraseasonal variability patterns, the vertical-zonal structures of the first two leading predictable modes of Madden–Julian Oscillation(MJO), and its eastward propagation; but the simulated MJO speed is significantly slower than observed. Compared with the T42 version, the high resolution version(T159) demonstrates improved simulation with respect to the climatology, interannual variance, monsoon–ENSO lead–lag correlation, spatial structures of the leading mode of the Asian–Australian monsoon rainfall variability, and the eastward propagation of the MJO. 展开更多
关键词 coupled climate model earth system model climate variability
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Global Climate Internal Variability in a 2000-year Control Simulation with Community Earth System Model(CESM) 被引量:13
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作者 WANG Zhiyuan LI Yao +1 位作者 LIU Bin LIU Jian 《Chinese Geographical Science》 SCIE CSCD 2015年第3期263-273,共11页
Using the low-resolution (T31, equivalent to 3.75°× 3.75°) version of the Community Earth System Model (CESM) from the National Center for Atmospheric Research (NCAR), a global climate simulation ... Using the low-resolution (T31, equivalent to 3.75°× 3.75°) version of the Community Earth System Model (CESM) from the National Center for Atmospheric Research (NCAR), a global climate simulation was carried out with fixed external forcing factors (1850 Common Era. (C.E.) conditions) for the past 2000 years. Based on the simulated results, spatio-temporal structures of surface air temperature, precipitation and internal variability, such as the E1 Nifio-Southem Oscillation (ENSO), the Atlantic Multi-decadal Oscilla- tion (AMO), the Pacific Decadal Oscillation (PDO), and the North Atlantic Oscillation (NAO), were compared with reanalysis datasets to evaluate the model performance. The results are as follows: 1) CESM showed a good performance in the long-term simulation and no significant climate drift over the past 2000 years; 2) climatological patterns of global and regional climate changes simulated by the CESM were reasonable compared with the reanalysis datasets; and 3) the CESM simulated internal natural variability of the climate system performs very well. The model not only reproduced the periodicity of ENSO, AMO and PDO events but also the 3-8 years vari- ability of the ENSO. The spatial distribution of the CESM-simulated NAO was also similar to the observed. However, because of weaker total irradiation and greenhouse gas concentration forcing in the simulation than the present, the model performances had some differences from the observations. Generally, the CESM showed a good performance in simulating the global climate and internal natu- ral variability of the climate system. This paves the way for other forced climate simulations for the past 2000 years by using the CESM. 展开更多
关键词 Community earth System Model (CESM) climate simulation past 2000 years climate system intemal variability
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Orbital Spin: A New Hypothesis to Explain Precession of Equinox—The Third Motion of Earth
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作者 Rama Chandra Murthy Mothe 《International Journal of Astronomy and Astrophysics》 2014年第1期20-28,共9页
In this paper, the phenomena of Earth’s motion about its own axis, the ecliptic plane of the Earth’s orbit around the Sun, the definitions of equinoxes, the precession of equinoxes, Earth’s wobble and other astrono... In this paper, the phenomena of Earth’s motion about its own axis, the ecliptic plane of the Earth’s orbit around the Sun, the definitions of equinoxes, the precession of equinoxes, Earth’s wobble and other astronomical terminology are briefly described. Some of the existing theories explaining the precession of equinox and their inadequacies are brought out. New Hypothesis is that precession of equinoxes is a direct result of Orbital spin of Earth in a retrograde direction—a celestial phenomenon similar to that of Moon’s Orbital spin around the Earth. The study of Moon’s orbit round the Earth reveals the exact movement of Earth’s orbit, which causes precession of equinoxes without any ambiguity. The analogy presented herein demonstrates the plausible hypothesis. 展开更多
关键词 PRECESSION of EQUINOX THIRD Motion of earth ORBITAL spin
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Fermions: Spin, Hidden Variables, Violation of Bell’s Inequality and Quantum Entanglement
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作者 Doron Kwiat 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1613-1627,共15页
Using real fields instead of complex ones, it was recently claimed, that all fermions are made of pairs of coupled fields (strings) with an internal tension related to mutual attraction forces, related to Planck’s co... Using real fields instead of complex ones, it was recently claimed, that all fermions are made of pairs of coupled fields (strings) with an internal tension related to mutual attraction forces, related to Planck’s constant. Quantum mechanics is described with real fields and real operators. Schrodinger and Dirac equations then are solved. The solution to Dirac equation gives four, real, 2-vectors solutions ψ1=(U1D1)ψ2=(U2D2)ψ3=(U3D3)ψ4=(U4D4)where (ψ1,ψ4) are coupled via linear combinations to yield spin-up and spin-down fermions. Likewise, (ψ2,ψ3) are coupled via linear combinations to represent spin-up and spin-down anti-fermions. For an incoming entangled pair of fermions, the combined solution is Ψin=c1ψ1+c4ψ4where c1and c4are some hidden variables. By applying a magnetic field in +Z and +x the theoretical results of a triple Stern-Gerlach experiment are predicted correctly. Then, by repeating Bell’s and Mermin Gedanken experiment with three magnetic filters σθ, at three different inclination angles θ, the violation of Bell’s inequality is proven. It is shown that all fermions are in a mixed state of spins and the ratio between spin-up to spin-down depends on the hidden variables. 展开更多
关键词 FERMIONS spin Hidden Variables Bell’s Inequality Violation spin Entanglement
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Application of Rare Earth Spin Finishes Chloride on PET/PA Composite Super-fine Denier Fiber
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作者 车江宁 袁琴华 朱庆华 《Journal of China Textile University(English Edition)》 EI CAS 1998年第4期76-78,共3页
The primariy application of rare - earth spin finishes on PET/PA composite super - fine denier fiber has been studied in this paper. It results in the improvement of fi-ber’s properties, such as increased whiteness, ... The primariy application of rare - earth spin finishes on PET/PA composite super - fine denier fiber has been studied in this paper. It results in the improvement of fi-ber’s properties, such as increased whiteness, brightness and brilliance, effective and uniform spliting of compos-ite fiber into super - fine denier fiber and enhanced dye-ing effect. 展开更多
关键词 RARE earth COMPOSITE super - fine denier fiber spin finishes
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NMR Study on Structural Characteristics of Rare Earth Doped Boro-Alumino-Silicate Glasses 被引量:5
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作者 陆春华 倪亚茹 +1 位作者 张其土 许仲梓 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第4期413-417,共5页
The structural characteristics of Re2O3 doped B2O3-Al2O3-SiO2 glasses and factors such as the component and heat-treating conditions affecting the glass structure were investigated by magic angle spin nuclear magnetic... The structural characteristics of Re2O3 doped B2O3-Al2O3-SiO2 glasses and factors such as the component and heat-treating conditions affecting the glass structure were investigated by magic angle spin nuclear magnetic resonance (MAS NMR) spectroscopy and differential thermal analysis (DTA). It is found that, in B2O3-Al2O3-SiO2 glass, the boron (4), and Al(5), Al(6) changes to Al(4). On the other hand, compared with Ba^2+ , RE^3+ can accumulate the boron network because of its higher field strength, which results in a large network structure. With the increase of samarium oxide, the silicate coordination Qa(3T) will have predominance gradually. Heat-treatment has little effect on the boron and aluminum coordination sites in the glass structure. 展开更多
关键词 glass forming glass structure magic angle spin nuclear magnetic resonance boro-alumino-silicate glass rare earths
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Spin Dependent Hopping in Ti Doped La_(0.67)Ca_(0.33)MnO_3 被引量:1
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作者 黄宝歆 刘宜华 +3 位作者 张汝贞 原晓波 王成建 梅良模 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第6期803-807,共5页
A systematic investigation of the magnetic and transport properties of Ti doped La_(0.67)Ca_(0.33)MnO_3 was reported. The Ti substitution for Mn ions results in a reduction in ferromagnetism and conductivity. The meta... A systematic investigation of the magnetic and transport properties of Ti doped La_(0.67)Ca_(0.33)MnO_3 was reported. The Ti substitution for Mn ions results in a reduction in ferromagnetism and conductivity. The metal-insulator transition temperature is close to Curie temperature which decreases from 274 to 82 K as x increases from 0 to 0.17. The most important effect of Ti doping is to introduce spin clusters in the samples due to the distortion of local lattice and the inhomogeneous magnetic structure induced primarily by the random distribution of Mn ions. A maximum magnetoresistance ratio as large as 90% in 1 T at 122 K was obtained for the sample with x=0.055, which is four times larger than that obtained for LCMO sample at 272 K. There is a remarkable field-history dependent MR in the cooling process for the doped samples while such phenomenon disappears in the warming run. The resistivity follows well the variable range hopping behavior in paramagnetic state. Both the size effect and spin dependent hopping of carriers between the spin clusters should be considered in this system. 展开更多
关键词 ceramic materials colossal magnetoresistance spin cluster rare earths
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Preparation and Magnetic Properties of Melt-Spinning Nd_2Fe_(14)B/α-Fe Nanocomposite Magnets 被引量:1
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作者 王伟 倪建森 +3 位作者 徐晖 周邦新 李强 王占勇 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第4期505-508,共4页
Nd_(11)Fe_(71)Co_8V_(1.5)Cr_1B_(7.5) magnet was prepared by melt-spinning and subsequently annealed. The effects of the wheel speed on the magnetic properties and microstructure were studied. The results reveal that f... Nd_(11)Fe_(71)Co_8V_(1.5)Cr_1B_(7.5) magnet was prepared by melt-spinning and subsequently annealed. The effects of the wheel speed on the magnetic properties and microstructure were studied. The results reveal that fine nanocomposite microstructure consisting of Nd_2Fe_(14)B and α-Fe phases can be developed at an optimum wheel speed of about 21 m·s^(-1). After optimal annealing (640 ℃×4 min), magnetic properties of B_r=0.64 T, (()_jH_c)=903.5 kA·m^(-1) and (BH)_(max)=71 (kJ·m^(-3)) were obtained for the bonded magnets. The addition of Cr element significantly reduces grain size, increasing the intrinsic coercivity and maximum magnetic energy product. 展开更多
关键词 nanocomposite magnets melt spinning exchange coupling rare earths
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Universal spin-dependent variable range hopping in wide-band-gap oxide ferromagnetic semiconductors 被引量:1
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作者 代由勇 颜世申 +3 位作者 田玉峰 陈延学 刘国磊 梅良模 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第3期477-481,共5页
This paper proposes a universal spin-dependent variable range hopping theoretical model to describe various experimental transport phenomena observed in wide-band-gap oxide ferromagnetic semiconductors with high trans... This paper proposes a universal spin-dependent variable range hopping theoretical model to describe various experimental transport phenomena observed in wide-band-gap oxide ferromagnetic semiconductors with high transition metal concentration. The contributions of the 'hard gap' energy, Coulomb interaction, correlation energy, and exchange interaction to the electrical transport are considered in the universal variable range hopping theoretical model. By fitting the temperature and magnetic field dependence of the experimental sheet resistance to the theoretical model, the spin polarization ratio of electrical carriers near the Fermi level and interactions between electrical carriers can be obtained. 展开更多
关键词 variable range hopping ferromagnetic semiconductors electrical transport spin polar-ization
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Texture Evolution in Nanocomposite Nd_2Fe_(140B/α-Fe Magnets Prepared by Direct Melt Spinning 被引量:1
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作者 王占勇 徐晖 +2 位作者 倪建森 金红明 周邦新 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第S1期298-301,共4页
Texture evolution in nanocomposite Nd_2Fe_ 14B/α-Fe magnets prepared by direct melt spinning was investigated. The free surface and wheel-contacted surface exhibit different texture direction. Modification of composi... Texture evolution in nanocomposite Nd_2Fe_ 14B/α-Fe magnets prepared by direct melt spinning was investigated. The free surface and wheel-contacted surface exhibit different texture direction. Modification of composition not only enhances magnetic properties, but also changes texture direction of the ribbon. Low temperature heat treatment can increase the magnetic properties to some extent, and high temperature annealing decreases the magnetic properties. Both low and high temperature heat treatment have effects on grain orientation, but the difference still exists between the two surfaces of the ribbon. So it is infeasibility to prepare anisotropic Nd_2Fe_ 14B/α-Fe nanocomposite magnets by direct melt spinning. 展开更多
关键词 nanocomposite magnet Nd_2Fe_ 14B/α-Fe melt spinning anisotropic magnets rare earths
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Earth System Model FGOALS-s2: Coupling a Dynamic Global Vegetation and Terrestrial Carbon Model with the Physical Climate System Model 被引量:1
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作者 王军 包庆 +3 位作者 Ning ZENG 刘屹岷 吴国雄 纪多颖 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第6期1549-1559,共11页
Earth System Models (ESMs) are fundamental tools for understanding climate-carbon feedback. An ESM version of the Flexible Global Ocean-Atmosphere-Land System model (FGOALS) was recently developed within the IPCC ... Earth System Models (ESMs) are fundamental tools for understanding climate-carbon feedback. An ESM version of the Flexible Global Ocean-Atmosphere-Land System model (FGOALS) was recently developed within the IPCC AR5 Coupled Model Intercomparison Project Phase 5 (CMIP5) modeling framework, and we describe the development of this model through the coupling of a dynamic global vegetation and terrestrial carbon model with FGOALS-s2. The performance of the coupled model is evaluated as follows. The simulated global total terrestrial gross primary production (GPP) is 124.4 PgC yr-I and net pri- mary production (NPP) is 50.9 PgC yr-1. The entire terrestrial carbon pools contain about 2009.9 PgC, comprising 628.2 PgC and 1381.6 PgC in vegetation and soil pools, respectively. Spatially, in the tropics, the seasonal cycle of NPP and net ecosystem production (NEP) exhibits a dipole mode across the equator due to migration of the monsoon rainbelt, while the seasonal cycle is not so significant in Leaf Area Index (LAI). In the subtropics, especially in the East Asian monsoon region, the seasonal cycle is obvious due to changes in temperature and precipitation from boreal winter to summer. Vegetation productivity in the northern mid-high latitudes is too low, possibly due to low soil moisture there. On the interannual timescale, the terrestrial ecosystem shows a strong response to ENSO. The model- simulated Nifio3.4 index and total terrestrial NEP are both characterized by a broad spectral peak in the range of 2-7 years. Further analysis indicates their correlation coefficient reaches -0.7 when NEP lags the Nifio3.4 index for about 1-2 months. 展开更多
关键词 earth System Model (ESM) Dynamic Global Vegetation Model (DGVM) carbon cycle sea- sonal cycle interannual variability
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Effect of the Variable B-Field on the Dynamic of a Central Electron Spin Coupled to an Anti-Ferromagnetic Qubit Bath 被引量:1
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作者 Martin Tchoffo Georges Collince Fouokeng +5 位作者 Siaka Massou Ngwa Engelbert Afuoti Issofa Nsangou Lukong Cornelius Fai Alex Ghislain Tchouadeu Jean-Pierre Kenné 《World Journal of Condensed Matter Physics》 2012年第4期246-256,共11页
This present issue is an extension of the work of Y. Xiao-Zhong et al. who investigated the influence of constant external magnetic field on the decoherence of a central electron spin of atom coupled to an anti-ferrom... This present issue is an extension of the work of Y. Xiao-Zhong et al. who investigated the influence of constant external magnetic field on the decoherence of a central electron spin of atom coupled to an anti-ferromagnetic environment. We have shown in this work that the character variability of the field induces oscillations amongst the eigen modes of the environment. This observation is made via the derivation of the transition probability density of state, a manner by which critical parameters (parameters where transition occur) of the system could be obtained as it shows resonance peak. We equally observed that the two different magnons modes resulting from the frequency splitting via the application of the time-varying external B-Field, exhibit each a resonant peak of similar amplitude at different temperature ranges. This additional information shows that the probability for the central spin system to remain in its initially prepared diabatic state is enhanced for some temperature ranges for the corresponding two magnon modes. Hence, these temperature ranges where the probability density is maximum could save as decoherence free environment;an important requirement for the implementation of quantum computation and information processing in solid state circuitry. The theoretical and numerical results presented for the decoherence time and the probability density are that of a decohered central electron spin coupled to an anti-ferromagnetic spin bath. The theory is based on a spin wave approximation and on the density matrix using both transformations of Bloch, Primakov and Bogoliobuv in the adiabatic limit. 展开更多
关键词 Decoherence spin Wave Anti-Ferromagnetic Environment CENTRAL spin VARIABLE B-Field
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Photo-Catalyzed Rare Earth Materials with Ability to Translate Free Radicals into Negative Ions 被引量:2
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作者 金宗哲 张志力 +1 位作者 卫罡 黄丽容 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第2期183-185,共3页
Materials with function of producing negative ions effection,containing valency-variable rare earth elements and semiconductor oxide,were fabricated.Free radicals produced by the materials were tested.The result shows... Materials with function of producing negative ions effection,containing valency-variable rare earth elements and semiconductor oxide,were fabricated.Free radicals produced by the materials were tested.The result shows that the materials can produce quite a few free radicals as·O^-_2 no matter whether they are under illumination of ultraviolet radiation or under visible light radiation,or under no light radiation, demonstrating semiconductor oxide can be catalysed under the visible light radiation.At the same time the result shows there is direct relation between the number of free radicals and of the negative ion produced by the materials,which meant that during photo-catalyzed and redox process of valency-variable rare earth elements free radicals translate into negative ions. A circular model is presented involving circulating change of valency-variable rare earth elements and water and oxygen absorbed on the surface of materials under the condition of photocatalysis. 展开更多
关键词 negative ions material valency-variable rare earth free radicals rare earths
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Global air-sea CO_(2) exchange fl ux since 1980s: results from CMIP6 Earth System Models 被引量:1
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作者 Baoxiao QU Jinming SONG +3 位作者 Xuegang LI Huamao YUAN Kun ZHANG Suqing XU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第4期1417-1436,共20页
The ocean could profoundly modulate the ever-increasing atmospheric CO_(2) by air-sea CO_(2) exchange process,which is also able to cause signifi cant changes of physical and biogeochemical properties in return.In thi... The ocean could profoundly modulate the ever-increasing atmospheric CO_(2) by air-sea CO_(2) exchange process,which is also able to cause signifi cant changes of physical and biogeochemical properties in return.In this study,we assessed the long-term average and spatial-temporal variability of global air-sea CO_(2) exchange fl ux(F CO_(2))since 1980s basing on the results of 18 Coupled Model Intercomparison Project Phase 6(CMIP6)Earth System Models(ESMs).Our fi ndings indicate that the CMIP6 ESMs simulated global CO_(2) sink in recent three decades ranges from 1.80 to 2.24 Pg C/a,which is coincidence with the results of cotemporaneous observations.What’s more,the CMIP6 ESMs consistently show that the global oceanic CO_(2) sink has gradually intensifi ed since 1980s as well as the observations.This study confi rms the simulated F CO_(2) could reach agreements with the observations in the aspect of primary climatological characteristics,however,the simulation skills of CIMP6 ESMs in diverse open-sea biomes are unevenness.None of the 18 CMIP6 ESMs could reproduce the observed F CO_(2) increasement in the central-eastern tropical Pacifi c and the midlatitude Southern Ocean.Defi ciencies of some CMIP6 ESMs in reproducing the atmospheric pressure systems of the Southern Hemisphere and the El Niño-Southern Oscillation(ENSO)mode of the tropical Pacifi c are probably the major causes. 展开更多
关键词 air-sea CO_(2)fl ux Coupled Model Intercomparison Project Phase 6(CMIP6) earth System Model(ESM) long-term average spatial-temporal variability
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Anisotropy of rare-earth magnets 被引量:2
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作者 R.Skomski D.J.Sellmyer 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第4期675-679,共5页
Rare-earth intermetallics such as Nd2Fe14B and Sm-Co are widely used as high-performance permanent magnets, because they combine high magnetocrystalline anisotropy with reasonable magnetization and Curie temperature. ... Rare-earth intermetallics such as Nd2Fe14B and Sm-Co are widely used as high-performance permanent magnets, because they combine high magnetocrystalline anisotropy with reasonable magnetization and Curie temperature. The anisotropy is a combined effect of spin-orbit coupling and electrostatic crystal-field interactions. The main contribution comes from the rare-earth 4f electrons, which are well-screened from the crystalline environment but exhibit a strong spin-orbit coupling. In this limit, the magnetocrystalline anisotropy has a very transparent physical interpretation, the anisotropy energy essentially being equal to the energy of Hund's-rules 4f ion in the crystal field. The corresponding expression for the lowest-order uniaxial anisotropy constant K1 is used to discuss rare-earth substitutions, which have recently attracted renewed interest due to shifts in the rare-earth production and demand. Specific phenomena reviewed in this article are the enhancement of the anisotropy of Sm2Fe17 due to interstitial nitrogen, the use of Sm-Co magnets for high-temperature applications, and the comparison of rare-earth single-ion anisotropy with other single-ion and two-ion mechanisms. 展开更多
关键词 magnetic anisotropy spin-orbit coupling crystal-field interaction interstitial modification permanent magnets rare earths
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Magnetocrystalline anisotropy and spin reorientation transition of DyMn_6Sn_6 compound 被引量:1
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作者 郭光华 秦江 张海贝 《中国有色金属学会会刊:英文版》 EI CSCD 2007年第3期514-518,共5页
The spin-reorientation transition of intermetallic compound DyMn6Sn6 was investigated by applying the molecular field theory. The temperature dependence of easy magnetization direction of compound and the magnetic mom... The spin-reorientation transition of intermetallic compound DyMn6Sn6 was investigated by applying the molecular field theory. The temperature dependence of easy magnetization direction of compound and the magnetic moment directions of Dy and Mn ions were theoretically calculated and they have good agreement with the experimental data. In the framework of single ion model, the temperature dependence of magnetocrystalline anisotropic constants K1R and K2R of Dy ion were also calculated. The results show that the fourth-order crystal field parameter, B 40, and the corresponding second-order magnetocrystalline anisotropic constant, K2R, of Dy ion must be taken into account in order to explain the spin-reorientation transition satisfactorily. The competition between K2R and K1R plays a key role in the spin-reorientation transition of DyMn6Sn6. 展开更多
关键词 金属特性 自旋处理 磁晶体 粒子转移
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Hydriding and dehydriding characteristics of nanocrystalline and amorphous Mg_(20-x)La_xNi_(10)(x=0-6) alloys prepared by melt-spinning 被引量:1
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作者 张羊换 赵栋梁 +3 位作者 任慧平 郭世海 王青春 王新林 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第3期514-519,共6页
In order to improve the hydrogenation and dehydrogenation performances of the Mg2Ni-type alloys, Mg was partially substituted by La in the alloy, and melt spinning technology was used for the preparation of the Mg20-x... In order to improve the hydrogenation and dehydrogenation performances of the Mg2Ni-type alloys, Mg was partially substituted by La in the alloy, and melt spinning technology was used for the preparation of the Mg20-xLaxNi10 (x=0, 2, 4, 6) hydrogen storage alloys. The structures of the alloys were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). It was found that no amorphous phase formed in the as-spun La-free alloy, but the as-spun alloys containing La held a major amorphous phase. When La content x≤2, the major phase in the as-cast alloys was Mg2Ni phase, but with further increase of La content, the major phase of the as-cast alloys changed into LaNi5+LaMg3 phase. Thermal stability of the as-spun alloys was studied by differential scanning calorimetry (DSC), showing that spinning rate was a negligible factor on the crystallization temperature of the amorphous phase. The hydrogen absorption and desorption kinetics of the as-cast and as-spun alloys were measured using an automatically controlled Sieverts apparatus, confirming that the hydrogen absorption and desorption capacities and kinetics of the as-cast alloys clearly increased with rising La content. For La content x=2, the as-spun alloy displayed optimal hydrogen desorption kinetics at 200 ℃. 展开更多
关键词 Mg2Ni-type hydrogen storage alloy MELT-spinNING structure hydriding and dehydriding characteristics rare earths
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Influence of annealing on spin state of cobalt ions in La_(1-x)Sr_xCoO_3(0≤x≤0.5) system
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作者 蒋丽珍 许祝安 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第1期92-95,共4页
Perovskite oxide La1-xSrxCoO3(0≤x≤0.5) series were prepared and effect of oxygen annealing on crystal structure and magnetic susceptibility were studied.High-temperature susceptibility could be well fitted by Curi... Perovskite oxide La1-xSrxCoO3(0≤x≤0.5) series were prepared and effect of oxygen annealing on crystal structure and magnetic susceptibility were studied.High-temperature susceptibility could be well fitted by Curie-Weiss law for all Sr-doped samples.Weiss constant and effective magnetic moment were determined, and their variations with Sr doping and oxygen annealing condition were obtained.The result suggested that by assuming that the Co3+ ions were in the intermediate-spin(IS) state, most of the Co4+ ions in the as-prepared samples might be in the high-spin(HS) state, but both the Co3+ and Co4+ ions might be in the IS state after oxygen annealing, which indicated that annealing in flowing oxygen could cause transition of the spin state of Co4+ ions from the HS state to IS state. 展开更多
关键词 La1-xSrxCoO3 oxygen annealing magnetic susceptibility spin state rare earths
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Microstructure and Electrochemical Characteristics of Melt-Spinning Alloy Ml(NiCoMnAl)_5
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作者 WEN Ming fen 1,2 , CHEN Lian 1, TONG Min 1, CHEN De min 1, ZHAI Yu chun 2 ( 1. Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015, China 2. Department of Materials and Metallurgy, Northeastern University, Shenyang 11000 《Journal of Rare Earths》 SCIE EI CAS CSCD 2001年第1期80-80,共1页
The microstructure and electrochemical characteristics of Ml(NiCoMnAl) 5 alloys prepared by both the melt spinning method and the conventional induction melting were investigated and compared. SEM and XRD studies sh... The microstructure and electrochemical characteristics of Ml(NiCoMnAl) 5 alloys prepared by both the melt spinning method and the conventional induction melting were investigated and compared. SEM and XRD studies show that the microstructure of melt spinning alloys is columnar structure. With increasing melt spinning rate, the crystal grains become finer and preferentially grow along (111)[111] direction. The melt spinning and cast alloys belong to CaCu 5 type hexagonal crystal structure. The electrochemical measurements show that the initial capacities of melt spinning alloy electrodes are all above 210 mAh·g -1 with good activation behavior, reaching their maximum capacities after two charge discharge cycles. The maximum capacity (294 mAh·g -1 ) of melt spinning (10 m·s -1 ) alloy electrodes is as the same as that of as cast alloy electrode, and stability of charge discharge cycles of all melt spinning alloy electrodes is better than that of the as cast alloy electrodes. When charged at 600 mA·g -1 , the capacity of melt spinning (10 m·s -1 ) alloy electrode could reach 65% of its maximum capacity about 45 min with high rate discharge capability; but with the cycle number increasing, the stability of its capacity is less than that electrodes of melt spinning rate. 展开更多
关键词 rare earths melt spinning method hydrogen storage alloy electrode electrochemical characteristics columnar structure
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Effects of Grounding (Earthing) on Massage Therapists: An Exploratory Study
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作者 Gaétan Chevalier Sheila Patel +4 位作者 Lizabeth Weiss Christopher Pruitt Brook Henry Deepak Chopra Paul J. Mills 《Health》 2018年第2期228-250,共23页
It is well known that massage therapists often develop a number of health problems relatively early on in their career. A preliminary study showed that grounding massage therapists during their work may alleviate some... It is well known that massage therapists often develop a number of health problems relatively early on in their career. A preliminary study showed that grounding massage therapists during their work may alleviate some of the health problems they encounter. A doubled-blind randomized controlled trial was designed to examine the effects of working and sleeping grounded for 4 weeks on massage therapists’ blood viscosity, stress (through HRV), inflammation (IFN-γ, IL-6, TNF-α, and hsCRP) and oxidative stress (MPO and MDA) biomarkers. The results show stress reduction as measured by heart rate, respir-atory rate and hear rate variability (HRV) and a lowering effect on blood viscosity that lasted for at least one week after ungrounding, with systolic blood viscosity becoming significantly lower at the end of the study. Inflammation markers (IFN-γ, TNF-α, and hsCRP) increased rapidly, within one week, after ungrounding. The findings suggest that grounding is beneficial for massage therapists in multiple domains relevant to health and wellbeing. 展开更多
关键词 earthING GROUNDING Heart Rate variability (HRV) Blood Viscosity INFLAMMATORY Biomarkers Oxidative Stress
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