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Study on the interannual variability of the Kerama Gap transport and its relation to the Kuroshio/Ryukyu Current system
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作者 Han Zhou Kai Yu +3 位作者 Jianhuang Qin Xuhua Cheng Meixiang Chen Changming Dong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期1-14,共14页
An analysis of a 68-year monthly hindcast output from an eddy-resolving ocean general circulation model reveals the relationship between the interannual variability of the Kerama Gap transport(KGT)and the Kuroshio/Ryu... An analysis of a 68-year monthly hindcast output from an eddy-resolving ocean general circulation model reveals the relationship between the interannual variability of the Kerama Gap transport(KGT)and the Kuroshio/Ryukyu Current system.The study found a significant difference in the interannual variability of the upstream and downstream transports of the East China Sea-(ECS-)Kuroshio and the Ryukyu Current.The interannual variability of the KGT was found to be of paramount importance in causing the differences between the upstream and downstream ECS-Kuroshio.Additionally,it contributed approximately 37%to the variability of the Ryukyu Current.The interannual variability of the KGT was well described by a two-layer rotating hydraulic theory.It was dominated by its subsurface-intensified flow core,and the upper layer transport made a weaker negative contribution to the total KGT.The subsurface flow core was found to be mainly driven by the subsurface pressure head across the Kerama Gap,and the pressure head was further dominated by the subsurface density anomalies on the Pacific side.These density anomalies could be traced back to the eastern open ocean,and their propagation speed was estimated to be about 7.4 km/d,which is consistent with the speed of the local first-order baroclinic Rossby wave.When the negative(positive)density anomaly signal reached the southern region of the Kerama Gap,it triggered the increase(decrease)of the KGT towards the Pacific side and the formation of an anticyclonic(cyclonic)vortex by baroclinic adjustment.Meanwhile,there is an increase(decrease)in the upstream transport of the entire Kuroshio/Ryukyu Current system and an offshore flow that decreases(increases)the downstream Ryukyu Current. 展开更多
关键词 Kerama Gap KUROSHIO Ryukyu Current OGCM for the earth Simulator(ofES) hydraulic theory
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Some New Results from the Electron Theory on the Elastical of Alkahoe Earth Metals and Rare Earth Elements
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作者 崔秀山 邢胜娣 《Journal of Beijing Institute of Technology》 EI CAS 1994年第1期31+26-32,共8页
With the introduction of Poisson's ratio in the expression of Young's modulus,nearly all the theoretical values of the various elastic moduli for the alkaline earth metals and rare earth elements can be greatl... With the introduction of Poisson's ratio in the expression of Young's modulus,nearly all the theoretical values of the various elastic moduli for the alkaline earth metals and rare earth elements can be greatly refined, with the single exception of the theoreticalvalue of Young's modulus for Pr which is slightly increased This points to the validityof the new theory, that the bulk modulus is independent of the Poisson's ratio, and further that the valency electron structures of solids as determined by Yu's theory are correct. 展开更多
关键词 alkaline earth metals rare earth elements/electron theory of elasticity
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Possible Evolutionary Models in the Initially Hydride Earth Theory
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作者 Kudryavtsev Pavel 《International Journal of Geosciences》 CAS 2023年第5期377-426,共50页
A modern view of the properties of chemical elements has confirmed the theory of the hot origin of the Earth. The next step in developing this theory was the hypothesis of the initial hydride Earth. In this work, we a... A modern view of the properties of chemical elements has confirmed the theory of the hot origin of the Earth. The next step in developing this theory was the hypothesis of the initial hydride Earth. In this work, we attempted to find additional evidence for this hypothesis and show additional effects that flow from it. The effect of the physical properties of atoms and ions on their behavior during the formation of the Earth was studied. The maximum contribution to the distribution of elements was made by those elements whose content in the original protoplanets of the disk was the maximum. Correlation dependence is obtained, which allows one to calculate the distribution of elements in the protoplanetary disk. It was shown that hydrogen was the main element in the proto substance located in the zone of the Earth’s formation. In this case, various chemical compounds formed, most represented by hydrogen compounds—hydrides. Since the pressure inside the Earth is 375 GPa, this factor forces the chemical compounds to adopt stoichiometry and structure that would not be available in atmospheric conditions. It is shown that many chemical elements at high pressure in a hydrogen medium form simple hydrides and super hydrides—polyhydrides with high hydrogen content. Pressure leads to a higher density of matter inside the planet. Given the possibility of forming polyhydrides, there is the possibility of binding the initially available hydrogen in an amount that can reach 49.3 mole%. Young Earth could contain about 10.7 mass% of hydrogen in hydrides, polyhydrides, and adsorbed form is almost twice higher than previous estimates. This fact additionally confirms the theory of the original hydride Earth. In hydrides, the occurrence of the phenomenon of superconductivity was discovered. Polyhydrides were shown as potential superconductors with a high critical temperature above 200 K. We, based on these data, hypothesized the presence of superconducting properties in the Earth’s core, which explains the presence of a magnetic field in the Earth, as well as the unevenness and instability of this field and the possibility of migration of the Earth’s poles. The fact that the Earth has a hydroid core causes its change in time due to the instability of hydrides. Arranged several possible models of the destruction of the Earth’s core. The calculations showed that both models give close results. These results give predictions that can be measured. The proposed models also made it possible to estimate the initial size of the Earth. Possible ways of further testing the hypothesis of the initial hydride Earth is shown. 展开更多
关键词 theory of the Hot Origin of the earth Magnetic Separation of Elements Atom Ionization Energy Hydrides Polyhydrides earth Expansion Superconductivity of the earth’s Core
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Effects of Earth's curvature and radial heterogeneity in dislocation studies:Case studies of the 2008 Wenchuan earthquake and the 2004 Sumatra earthquake 被引量:4
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作者 Guangyu Fu Wenke Sun +2 位作者 Yoichi Fukuda Shanghua Gao Takashi Hasegawa 《Earthquake Science》 CSCD 2010年第4期301-308,共8页
Recently, effects of Earth's curvature and radial heterogeneity on coseismic deformations are often investi- gated based on the 2004 Sumatra earthquake. However, such effects are strongly related to earthquake types.... Recently, effects of Earth's curvature and radial heterogeneity on coseismic deformations are often investi- gated based on the 2004 Sumatra earthquake. However, such effects are strongly related to earthquake types. As a low dip angle event, the 2004 Sumatra earthquake is not a good seismic case for such a topic since the effects for moderate dip angle events are much bigger. In this study, the half-space and spherical dislocation theories are used, respectively, to calculate co- seismic displacements caused by the 2008 Wenchuan earthquake and the 2004 Sumatra earthquake. Effects of Earth's curva- ture and stratification are investigated through the discrepancies of results calculated using the two dislocation theories. Re- sults show that the effects of Earth's curvature and stratification for the 2008 Wenchuan earthquake are much larger than those for the 2004 Sumatra earthquake. Ignoring the effects will cause errors up to 100%-200% in far field displacements for a moderate dip angle event like the 2008 Wenchuan earthquake. Such great effects are much bigger than those conclusions of previous studies. Besides, comparison with observations verifies that spherical dislocation theories yield better results than half-space ones in far fields. 展开更多
关键词 coseismic displacement dislocation theory earth model
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Spectroscopic Properties and Judd-Ofelt Theory Analysis of Er^(3+)-Doped Heavy Metal Oxyfluoride Silicate Glass 被引量:3
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作者 徐时清 杨中民 +3 位作者 戴世勋 张军杰 胡丽丽 姜中宏 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第3期375-380,共6页
Er^(3+)-doped heavy metal oxyfluoride silicate glass was fabricated and characterized, and the absorption spectrum and fluorescence spectrum of the glass were studied. The Judd-Ofelt intensity parameters Ω_t (t =2, ... Er^(3+)-doped heavy metal oxyfluoride silicate glass was fabricated and characterized, and the absorption spectrum and fluorescence spectrum of the glass were studied. The Judd-Ofelt intensity parameters Ω_t (t =2, 4, 6), spontaneous transition probability, fluorescence branching ratio and radiative lifetime of each energy levels for Er^(3+) were calculated by Judd-Ofelt theory, and stimulated emission cross-section of (()~4I_(13/2))→(()~4I_(15/2)) transition was calculated by McCumber theory. The results show that fluorescence full width at half maximum and stimulated emission cross-section of Er^(3+)-doped heavy metal oxyfluoride silicate glass are broad and large, respectively. Compared with other host glasses, the gain bandwidth property of Er^(3+)-doped heavy metal oxyfluoride silicate glass is close to those of tellurite and bismuth glasses, and has advantage over those of silicate, phosphate and germante glasses. 展开更多
关键词 inorganic nonmetallic materials heavy metal oxyfluoride silicate glass Er^(3+) ion spectroscopic properties Judd-ofelt theory rare earths
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Band-gap engineering of La1-xNdxAlO3(x = 0,0.25,0.50,0.75,1)perovskite using density functional theory:A modified Becke Johnson potential study
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作者 Sandeep D P Rai +6 位作者 A Shankar M P Ghimire Anup Pradhan Sakhya T P Sinha R Khenata S Bin Omran R K Thapa 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第6期376-382,共7页
The structural,electronic,and magnetic properties of the Nd-doped Rare earth aluminate,La1-xNdxAlO3(x = 0%to 100%) alloys are studied using the full potential linearized augmented plane wave(FP-LAPW) method within... The structural,electronic,and magnetic properties of the Nd-doped Rare earth aluminate,La1-xNdxAlO3(x = 0%to 100%) alloys are studied using the full potential linearized augmented plane wave(FP-LAPW) method within the density functional theory.The effects of the Nd substitution in La AlO3 are studied using the supercell calculations.The computed electronic structure with the modified Becke–Johnson(m BJ) potential based approximation indicates that the La1-xNdxAlO3 alloys may possess half-metallic(HM) behaviors when doped with Nd of a finite density of states at the Fermi level(EF).The direct and indirect band gaps are studied each as a function of x which is the concentration of Nddoped La AlO3.The calculated magnetic moments in the La1-xNdxAlO3 alloys are found to arise mainly from the Nd-4f state.A probable half-metallic nature is suggested for each of these systems with supportive integral magnetic moments and highly spin-polarized electronic structures in these doped systems at EF.The observed decrease of the band gap with the increase in the concentration of Nd doping in La AlO3 is a suitable technique for harnessing useful spintronic and magnetic devices. 展开更多
关键词 density functional theory rare earth aluminates perovskites electronic structures
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Density Function Theory Study of Electronic,Optical and Thermodynamic Properties of CaN_2,SrN_2 and BaN_2
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作者 徐士涛 张丽琴 CHENG Yan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第1期100-105,共6页
We put forward a first-principles density-functional theory about the impact of pressure on the structural and elastic properties of bulk CaN2,SrN2 and BaN2.The ground state properties of three alkaline earth diazenid... We put forward a first-principles density-functional theory about the impact of pressure on the structural and elastic properties of bulk CaN2,SrN2 and BaN2.The ground state properties of three alkaline earth diazenides were obtained,and these were in good agreement with previous experimental and theoretical data.By using the quasi-harmonic Debye model,the thermodynamic properties including the debye temperature ΘD,thermal expansion coefficient α,and gruneisen parameter y are successfully obtained in the temperature range from 0 to 100 K and pressure range from 0 to 100 GPa,respectively.The optical properties including dielectric function ε(ω),absorption coefficient α(ω),reflectivity coefficient R(ω),and refractive index n(ω) are also calculated and analyzed. 展开更多
关键词 density functional theory alkaline earth diazenides electronic structure thermodynamic properties optical properties pH
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Magnetic Isotope Theory of the Origin of Life on Earth
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作者 Aibassov Yerkin Nakisbekov Narymzhan +1 位作者 Yemelyanova Valentina Savizky Ruben 《Journal of Chemistry and Chemical Engineering》 2016年第6期301-304,共4页
The authors have proposed a new of magnetic isotope theory of life on Earth. According to this theory the initial impetus for the beginning of the synthesis of organic compounds is the impact of electromagnetic radiat... The authors have proposed a new of magnetic isotope theory of life on Earth. According to this theory the initial impetus for the beginning of the synthesis of organic compounds is the impact of electromagnetic radiation from the sun and energy radioactive isotopes. 展开更多
关键词 theory of the origin of life on earth magnetic field radioactive isotope synthesis organic compounds.
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Rebuilding the Ancestral Temple and Hosting Daluo Heaven and Earth Prayer and Enlightenment Ceremony
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作者 Wu Hui-Chiao 《Cultural and Religious Studies》 2020年第7期386-402,共17页
Kuo,Yeh-Tzu founded Taiwan’s Sung Shan Tsu Huei Temple in 1970.She organized more than 200 worshipers as a group named“Taiwan Tsu Huei Temple Queen Mother of the West Delegation to China to Worship at the Ancestral ... Kuo,Yeh-Tzu founded Taiwan’s Sung Shan Tsu Huei Temple in 1970.She organized more than 200 worshipers as a group named“Taiwan Tsu Huei Temple Queen Mother of the West Delegation to China to Worship at the Ancestral Temples”in 1990.At that time,the temple building of the Queen Mother Palace in Huishan of Gansu Province was in disrepair,and Temple Master Kuo,Yeh-Tzu made a vow to rebuild it.Rebuilding the ancestral temple began in 1992 and was completed in 1994.It was the first case of a Taiwan temple financing the rebuilding of a far-away Queen Mother Palace with its own donations.In addition,Sung Shan Tsu Huei Temple celebrated its 45th anniversary and hosted Yiwei Yuanheng Lizhen Daluo Tiandi Qingjiao(Momentous and Fortuitous Heaven and Earth Prayer Ceremony)in 2015.This is the most important and the grandest blessing ceremony of Taoism,a rare event for Taoism locally and abroad during this century.Those sacred rituals were replete with unprecedented grand wishes to propagate the belief in Queen Mother of the West.Stopping at nothing,Queen Mother’s love never ceases. 展开更多
关键词 Sung Shan Tsu Huei Temple Temple Master Kuo Yeh-Tzu Golden Mother of the Jade Pond Daluo Tiandi Qingjiao(Daluo heaven and earth Prayer Ceremony)
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Band gap calculation and photo catalytic activity of rare earths doped rutile TiO_2 被引量:13
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作者 边亮 宋绵新 +2 位作者 周天亮 赵效勇 戴清清 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第3期461-468,共8页
The density of states (DOS) of 17 kinds of rare earths (RE) doped rutile TiO2 was by using first-principles density functional theory (DFT) calculation. The band gap widths of RE doped futile TiO2 were important... The density of states (DOS) of 17 kinds of rare earths (RE) doped rutile TiO2 was by using first-principles density functional theory (DFT) calculation. The band gap widths of RE doped futile TiO2 were important factors for altering their absorbing wavelengths. The results show that RE ions could obviously reduce the band gap widths and form of energy of ruffle TiO2 except Lu, Y, Yb and Sc, and the order of absorbing wavelengths of RE doped ruffle TiO2 were the same as that of the results of calculation. The ratio of RE dopant was another important factor for the photo catalytic 'activity of RE doped rutile TiO2, and there was an optimal ratio of dopant. There was a constant for predigesting the calculation difficulty, respectively, which were 0.5mol.% and 100 mol^-1 under supposition. The band gap widths of RE doped rutile TiOz by DFT calculation were much larger than that by experiment. Finally, by transferring the calculation values to experiment values, it could be found and predicted that RE enlarged obviously the absorbing wavelengh of ruffle TiO2. In addition, the degree of RE ions edging out the Ti atom using the parameters of RE dements was computed. 展开更多
关键词 density functional theory ruffle TiO2 band gap rare earths
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Fluorescence and Judd-Ofelt analysis of rare earth complexes with maleic anhydride and acrylic acid 被引量:3
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作者 温世鹏 张小萍 +2 位作者 胡水 张立群 刘力 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第6期787-791,共5页
Two kinds of Eu-complexes, Eu(TTA)2(Phen)(AA) and Eu(TTA)2(Phen)(MA) (HTTA=2-Thenoyltrifluoroacetone, Phen=1,10- phenanthroline, AA=acrylic acid, MA=Maleic anhydride), which combined the excellent fluore... Two kinds of Eu-complexes, Eu(TTA)2(Phen)(AA) and Eu(TTA)2(Phen)(MA) (HTTA=2-Thenoyltrifluoroacetone, Phen=1,10- phenanthroline, AA=acrylic acid, MA=Maleic anhydride), which combined the excellent fluorescence properties of Eu(TTA)2(Phen)(H2O) and the reactivity of acrylic acid and maleic anhydride with radicals, were synthesized. The two complexes were characterized by elemental analysis, infrared (IR) spectra, and X-ray photoelectron spectroscopy (XPS). Based on the data shown from the fluorescent spectra of the Eu-MA and Eu-AA complexes, the Ωλ (λ=2 and 4) experimental intensity parameters were calculated. The results demonstrated that the Ω2 intensity parameters for the two complexes were smaller than those for the Eu(TTA)2(Phen)(H2O) complex, indicating that a less symmetrical chemical environment existed in the complexes. It implied that the radiative efficiency of the ^5D0 of these two complexes could be enhanced by ligand of MA and AA, respectively. The luminescent lifetime of the Eu-AA (r=-7.26×10^-4 s) or Eu-MA complex (r=-8.12×10^-4 s) was higher than that of the Eu(TTA)2(Phen)(H2O) complex, which was attributed to the substitution of the water molecule (H2O) in Eu(TTA)2(Phen)(H2O) by the MA or AA ligand. 展开更多
关键词 organic ligands XPS spectra Judd-ofelt theory rare earths
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Multisphere Tectonics of the Earth System 被引量:1
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作者 REN Jishun NIU Baogui +5 位作者 XU Qinqin ZHAO Lei LIU Jianhui LI Shan ZHU Junbin LIU Renyan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第3期727-741,共15页
The fundamental theoretical framework of the Multisphere Tectonics of the Earth System is as follows:(1)It intends to extend the geotectonic studies from the crustal and lithospheric tectonics to the multisphere tecto... The fundamental theoretical framework of the Multisphere Tectonics of the Earth System is as follows:(1)It intends to extend the geotectonic studies from the crustal and lithospheric tectonics to the multisphere tectonics of the Ear th system as a whole.(2)The global dynamics driven by both the Earth system and the cosmic celestial system:solar energy,multispheric interactions of the Earth system and the combined effects of the motions of celestial bodies in the cosmos syste m are the driving forces of various geological processes.(3)The Continent-Ocean transformation theory:the continent and ocean are two opposite yet unified geological units,which can be transformed into each other;neither continent nor ocean wi ll survive forever;there is no one-way development of continental accretion or ocean extinction;the simple theory of one-way continental accretion is regarded as invalid.(4)The continental crust and mantle are characterized by multiple layers,with different layers liable to slide along the interfaces between them,but corroboration is needed that continents move as a who le or even drift freely.(5)The cyclic evolution theory:the development of Earth’s tectonics is not a uniform change,but a spiral forward evolution,characterized by a combination of non-uniform,non-linear,gradual and catastrophic changes;different evolutionary stages(tectonic cycles)of Earth have distinctive global tectonic patterns and characteristics,one tectonic mo del should not be applied to different tectonic cycles or evolutionary stages.(6)The structure and evolution of Earth are asymmetric and heterogeneous,thus one tectonic model cannot be applied to different areas of the world.(7)The polycyclic evolution of the continental crust:the continental crust is formed by polycyclic tectonics and magmatism,rather than simply lateral or vertical accretion.(8)The role of deep faults:the deep fault zones cutting through different layers of the crus t a nd mantle usually play important roles in tectonic evolution.For example,the present-day mid-ocean ridge fault zones,transform fault zones and Benioff zones outline the global tectonic framework.Different tectonic cycles and stages of Earth’s evolutio n must have their own distinctive deep fault systems which control the global tectonic framework and evolutionary processes during different tectonic cycles and stages.Starting from the two mantle superplumes Jason(Pacific)and Tuzo(Africa),the study of the evolutionary process of the composition and structure of the crust and mantle during the great transformation an d reorganization of the Meso-Cenozoic tectonic framework in China and the other regions of Asia is a good demonstration of theory of Multisphere Tectonics of the Earth System. 展开更多
关键词 deep fault global dynamics cyclic evolution theory Multisphere Tectonics Continent-Ocean transformation theory earth system science
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Comparative study of different theories on active earth pressure 被引量:1
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作者 S.P.Yap F.A.Salman S.M.Shirazi 《Journal of Central South University》 SCIE EI CAS 2012年第10期2933-2939,共7页
Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on com... Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs. A number of analytical theories on active earth pressure were presented. Yet, there are limited studies on comparison between the theories. In this work, comparison between the theories with finite element analysis is done using the PLAXIS software. The comparative results show that in terms of distribution and magnitude of active earth pressure, RANKINE's theory possesses the highest match to the PLAXIS analysis. Parametric studies were also done to study the responses of active earth pressure distribution to varying parameters Increasing soil friction angle and wall friction causes decrease in active earth pressure. In contrast, active earth pressure increases with increasing soil unit weight and height of wall. RANK/NE's theory has the highest compatibility to finite element analysis among all theories, and utilization of this theory leads to proficient retaining wall design. 展开更多
关键词 active earth pressure retaining wall PLAXIS comparative study RANKINE's theory COULOMB's theory
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莎剧《安东尼与克莉奥佩特拉》中“New Heaven,New Earth”对圣经典故的借用及汉译
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作者 赵艾东 《圣经文学研究》 2023年第1期150-179,共30页
莎士比亚的文学作品对圣经语言和内容有大量借用和模仿;其中,悲剧《安东尼与克莉奥佩特拉》中的“new heaven,new earth”就与《启示录》中的“新天新地”存在互文关系。译者和读者若对圣经缺乏充分的了解,或是圣经文化圈外的“他者”,... 莎士比亚的文学作品对圣经语言和内容有大量借用和模仿;其中,悲剧《安东尼与克莉奥佩特拉》中的“new heaven,new earth”就与《启示录》中的“新天新地”存在互文关系。译者和读者若对圣经缺乏充分的了解,或是圣经文化圈外的“他者”,在汉译中就易发生问题。本文对圣经的天地观及其“新天新地”、其与《安东尼与克莉奥佩特拉》“新天新地”存在的三种互文关系以及剧中该典故的汉译等问题进行探讨,提出要想准确地理解和翻译西方经典,必须顾及文本产生的文化语境。 展开更多
关键词 新天新地 圣经 莎士比亚 《安东尼与克莉奥佩特拉》 互文性
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Effects of the Earth’s triaxiality on the polar motion excitations 被引量:2
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作者 Chen Wei Shen Wenbin 《Geodesy and Geodynamics》 2012年第2期1-7,共7页
This study aims to evaluate the significance of the Earth' s triaxiality to the polar motion theory. First of all, we compare the polar motion theories for both the triaxial and rotationally-symmetric Earth models, w... This study aims to evaluate the significance of the Earth' s triaxiality to the polar motion theory. First of all, we compare the polar motion theories for both the triaxial and rotationally-symmetric Earth models, which is established on the basis of the EGM2008 global gravity model and the MHB2000 Earth model. Then, we use the atmospheric and oceanic data (the NCEP/NCAR reanalyses and the ECCO assimulation products) to quantify the triaxiality effect on polar motion excitations. Numerical results imply that triaxiality only cause a small correction ( about 0. 1 - 0. 2 mas) to the geophysical excitations for the rotationally-symmetric case. The triaxiality correction is much smaller than the errors in the atmospheric and oceanic data, and thus can be neglected for recent studies on polar motion excitations. 展开更多
关键词 earth rotation theory dynamic figure parameter atmospheric-oceanic excitation
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Theoretical Analysis on Geometry Structure and Electronic Structure of LaNi_4Co
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作者 Liu Yang Wu Feng 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第4期469-469,共1页
The theoretical calculation of LaNi4Co, in which Co substituted for Ni at various sites, was performed by adopting the method of total energy based on the Density Functional Theory. The augmented plane wave function w... The theoretical calculation of LaNi4Co, in which Co substituted for Ni at various sites, was performed by adopting the method of total energy based on the Density Functional Theory. The augmented plane wave function was selected as a basis set in combination with Ultra-soft Pseudopotential technology. The geometry of LaNi5 was optimized and the parameters and properties of the structure were given. The theoretical results accord well with experiments. This method provides a theoretical approach for the structure prediction of such alloy. The calculations of total energy, electronic density of states and Mulliken population of LaNi4Co were carried out. The electronic structure of LaNi4Co and the change of the electronic structure due to the Co-substitution in LaNi5 alloy were analyzed from the calculated results. The stability of the alloy in which Ni was partially substituted by Co at various sites was compared and the factors controlling stability were discussed. The theoretical value of formation heat was calculated. 展开更多
关键词 alloy theoretical analysis GEOMETRY electronic structure heat of formation density functional theory LaNi4Co rare earths
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Earth Ecosystem Theory: IV Theory Application
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作者 Yang Dongfang Wang Fengyou +2 位作者 Zhu Sixi Wu Youfu He Huazhong 《Meteorological and Environmental Research》 CAS 2014年第12期4-8,共5页
By the application of earth ecosystem theory, three complementary mechanisms of earth ecosystem and ecological power of North Pacific are elaborated fully. Aided by three ecological sub-systems of earth ecosystem: te... By the application of earth ecosystem theory, three complementary mechanisms of earth ecosystem and ecological power of North Pacific are elaborated fully. Aided by three ecological sub-systems of earth ecosystem: terrestrial ecosystem, marine ecosystem and atmospheric ecosystem, running track of Si is showed. Under the theoretical guidance of three complementary mechanisms of earth ecosystem, we predict future climate mode of the earth, and climate in 2010 gave confirm. Therefore, the theoretical system of earth ecosystem is conductive to studying global issues, including change processes and tendencies of resource, ecology, environment and disaster. Then, it is beneficial to human healthy survival and sustainable development of the earth ecosystem. 展开更多
关键词 earth ecosystem theory APPLICATION China
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Analysis on the deployment of mining research supported by the grant program of Deep Resources Exploration and Mining
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作者 FAN Jun ZHANG Jialin +3 位作者 QIN Yuan WANG Hao GAO Yanan PEI Yongzhi 《煤田地质与勘探》 CAS CSCD 北大核心 2021年第3期1-7,共7页
The Deep Resources Exploration and Mining(DREAM)grant program,within the framework of The National Key Research and Development Program grants,is a pillar to implement China’s science and technology strategy in the a... The Deep Resources Exploration and Mining(DREAM)grant program,within the framework of The National Key Research and Development Program grants,is a pillar to implement China’s science and technology strategy in the area of deep resources exploitation.To tackle the insufficient of theories and technologies for the 1000-meter-deep mining,a section of mining,covering the research of basic theories,general technologies and application demonstration,was arranged in the layout of DREAM under the principle of"whole chain design,integrated implementation".In the aspect of basic research,DREAM mainly focused on the deep rock mechanics and mining theory,such as the in-situ mechanical behavior of deep rock,deep high stress induction and energy regulation theory.For the general and key technologies,DREAM supported the research on the mine construction and hoisting,excavation,rock breaking,mining methods and mining safety according to the characteristics of coal and metal mines.For the demonstration application,taking green,safe and efficient as the starting point,DREAM aimed at the green,safe and high efficiency mining,and the demonstration and leading role projects such as the low-waste and high-efficiency back fill mining.Since 2016,10 R&D projects have been funded,and 122 institutional participants with a total budget of RMB 235 million from the central government and RMB 480 million from enterprises as well as local governments have been involved.It is expected that the mining section of DREAM would contribute to establishing the theory and technology system in the area of deep mining and promoting the ability of deep resource exploitation in China. 展开更多
关键词 resource of deep earth MINING theory general technology application demonstration
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Influence of Neodymium on Amorphizability of RS Al-Fe-V-Si-Nd Alloys:An Investigation Using Time Dependent Nucleation Theory
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作者 庞华 郑立净 +1 位作者 张宝金 曾梅光 《Journal of Rare Earths》 SCIE EI CAS CSCD 2000年第4期293-297,共5页
Time dependent nucleation theory was applied to calculate the incubation time required for α Al nucleation in rapid solidified (RS) Al Fe V Si Nd alloys. The nucleation rates were calculated as a function of tem... Time dependent nucleation theory was applied to calculate the incubation time required for α Al nucleation in rapid solidified (RS) Al Fe V Si Nd alloys. The nucleation rates were calculated as a function of temperature, and the critical cooling rates required for the formation of amorphous α Al at different neodymium concentrations were calculated too. The addition of neodymium increases the amorphizablity of α Al by increasing the incubation time and decreasing the nucleation rate and the critical cooling rate. The calculations are fitted to experimental results when liquidus temperatures are estimated from an approximation, which treats Al Fe V Si Nd as quasi binary Al Fe system. 展开更多
关键词 rare earths NEODYMIUM amorphizablity Al Fe V Si Nd alloys time dependent nucleation theory rapid solidified processi?
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The Influence of Alkaline Earth Elements on Electronic Properties ofα-Si3N4 via DFT Calculation
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作者 ZHANG Jianwen HUANG Zhifeng +3 位作者 YIN Ziqian LI Meijuan CHEN Fei SHEN Qiang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第5期863-871,共9页
We used density functional theory(DFT)calculations to study the influence of alkali earth metal element(AE)doping on the crystal structure and electronic band structure ofα-Si3N4.The diversity of atomic radii of alka... We used density functional theory(DFT)calculations to study the influence of alkali earth metal element(AE)doping on the crystal structure and electronic band structure ofα-Si3N4.The diversity of atomic radii of alkaline earth metal elements results in structural expansion when they were doped into theα-Si3N4 lattice.Formation energies of the doped structures indicate that dopants prefer to occupy the interstitial site under the nitrogen-deficient environment,while substitute Si under the nitrogen-rich environment,which provides a guide to synthesizingα-Si3N4 with different doping types by controlling nitrogen conditions.For electronic structures,energy levels of the dopants appear in the bottom of the conduction band or the top of the valence band or the forbidden band,which reduces the bandgap ofα-Si3N4. 展开更多
关键词 FIRST-PRINCIPLES density functional theory calculations alkaline earth elements dopedα-Si3N4 photoluminescence material crystal structure electronic structure
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