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Atmospheric and Oceanic Excitations to LOD Change on Quasi-biennial Tune Scales

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Chinese Journal of Astronomy and Astrophysics 2006年第6期6卷 759-768页

作者： Li-Hua Ma De-chun liao Yan-Ben Han National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030

We use wavelet transform to study the time series of the Earth＇s rotation rate （length-of-day, LOD）, the axial components of atmospheric angular momentum （AAM） and oceanic angular momentum （OAM） in the period 1962-2005, and discuss the quasi-biennial oscillations （QBO） of LOD change. The results show that the QBO of LOD change varies remarkably in amplitude and phase. It was weak before 1978, then became much stronger and reached maximum values during the strong El Nino events in around 1983 and 1997. Results from analyzing the axial AAM indicate that the QBO signals in axial AAM are extremely consistent with the QBOs of LOD change. During 1963-2003, the QBO variance in the axial AAM can explain about 99.0% of that of the LOD, in other words, all QBO signals of LOD change are almost excited by the axial AAM, while the weak QBO signals of the axial OAM are quite different from those of the LOD and the axial AAM in both time-dependent characteristics and magnitudes. The combined effects of the axial AAM and OAM can explain about 99.1% of the variance of QBO in LOD change during this period.

关键词： Earth's variable rotation - atmospheric angular momentum - oceanic angular momentum

Excitation of Annual Polar Motion by the Pacific,Atlantic and Indian Oceans

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Chinese Journal of Astronomy and Astrophysics 2007年第6期7卷 831-838页

作者： JinMa Yong-Hong Zhou De-chun liao Jian-Li Chen Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 Graduate School of Chinese Academy of Sciences Beijing 100049 Center for Space Research University of Texas at Austin Austin TX 78712 USA

The global oceans play important roles in exciting the annual polar motion besides the atmosphere. However, it is still unclear about how large the regional oceans contribute to the annual polar motion. We investigate systemically the contributions of the Pacific, Atlantic and Indian Oceans to the excitation of the annual polar motion, based on the output data of ocean current velocity field and ocean bottom pressure field from ＂Estimating the Circulation and Climate of the Ocean （ECCO）＂ ocean circulation model over the period 1993-2005. The result shows that due to its particular location and shape, the Atlantic Ocean makes a less significant contribution to the x-component of the annual polar motion excitation than the Pacific and Indian Oceans, while all these three oceans contribute to the y-component of the annual polar motion excitation to some extent.

关键词： annual polar motion excitation oceanic angular momentum function(OAMF) -- atmospheric angular momentum function (AAMF)

Minimum Amount of Extracting Solvent of (A_(1)A_(2)…A_(t−1))/(A_(2)A_(3)…A_(t)) Separation When Using Non-barren Extracting Solvent

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Chinese Journal of Chemistry 2014年第10期32卷 1022-1028页

作者： Fu-Xiang Cheng Sheng Wu Song-Ling Wang Bo Zhang Yan Liu chun-Sheng liao chun-Hua Yan Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsPKU-HKU Joint Lab on Rare Earth Materials and Bioinorganic ChemistryPeking UniversityBeijing 100871China China Minmetals(Beijing)Research Institute of RE Co. LtdBeijing 100085China

Hyperlink extraction technology,by virtue of its remarkable advantage of decreasing the use of chemicals in multi-component separation,has been extensively employed in rare earth separation industry in *** hyperlink processes,non-barren extracting solvent and scrubbing agent solution which contain the component(s)involved in starting feed are employed in order to save both alkali for saponification and acid for *** amount of extracting solvent(denoted as S_(min))and that of scrubbing agent solution(denoted as W_(min))are important parameters to determine the consumption amounts of alkali and acid for a given countercurrent extraction *** article therefore discusses the influence of using non-barren extracting solvent and scrubbing agent solution on S_(min) and W_(min) of an(A_(1)A_(2)…A_(t−1))/(A_(2)A_(3)…A_(t))*** equations for S_(min) and W_(min) are derived,and the variation of the composition of final raffinate as well as that of final extract are determined,which will provide a valuable guidance for the design of hyperlink extraction processes of multi-component separation,such as rare earths separation.

关键词： minimum amount of extracting solvent rare earths hyperlink process multi-component separation

Electrical conductivity optimization of the Na3AlF6–Al2O3–Sm2O3 molten salts system for Al–Sm intermediate binary alloy production

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International Journal of Minerals,Metallurgy and Materials 2017年第9期24卷 1034-1042页

作者： chun-fa liao Yun-fen Jiao Xu Wang Bo-qing Cai Qiang-chao Sun Hao Tang Institute of Metallurgical and Chemical Engineering Jiangxi University of Science and Technology

Metal Sm has been widely used in making Al–Sm magnet alloy materials. Conventional distillation technology to produce Sm has the disadvantages of low productivity, high costs, and pollution generation. The objective of this study was to develop a molten salt electrolyte system to produce Al–Sm alloy directly, with focus on the electrical conductivity and optimal operating conditions to minimize the energy consumption. The continuously varying cell constant(CVCC) technique was used to measure the conductivity for the Na3AlF6–AlF3–LiF–MgF2–Al2O3–Sm2O3electrolysis medium in the temperature range from 905 to 1055°C. The temperature(t) and the addition of Al2O3(W(Al2O3)), Sm2O3(W(Sm2O3)), and a combination of Al2O3and Sm2O3into the basic fluoride system were examined with respect to their effects on the conductivity(κ) and activation energy. The experimental results showed that the molten electrolyte conductivity increases with increasing temperature(t) and decreases with the addition of Al2O3or Sm2O3or both. We concluded that the optimal operation conditions for Al–Sm intermediate alloy production in the Na3AlF6–AlF3–LiF–MgF2–Al2O3–Sm2O3system are W(Al2O3) + W(Sm2O3) = 3wt%, W(Al2O3):W(Sm2O3) = 7:3, and a temperature of 965 to 995°C, which results in satisfactory conductivity, low fluoride evaporation losses, and low energy consumption.

关键词： aluminium oxide samarium oxide molten salt electrical conductivity regression analysis Al–Sm intermediate alloy

Electrical conductivity of molten LiF–DyF3–Dy2O3–Cu2O system for Dy–Cu intermediate alloy production

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International Journal of Minerals,Metallurgy and Materials 2019年第6期26卷 701-709页

作者： Shu-mei Chen chun-fa liao Jue-yuan Lin Bo-qing Cai Xu Wang Yun-fen Jiao Institute of Metallurgy and Chemical Engineering Jiangxi University of Science and Technology

Dy–Cu intermediate alloys have shown substantial potential in the field of magnetostrictive and magnetic refrigerant ***,this study focused on investigating the electrical conductivity of molten-salt systems for the preparation of Dy–Cu alloys and on optimizing the corresponding operating *** electrical conductivity of molten LiF–DyF3–Dy2O3–Cu2O systems was measured from 910 to 1030°C using the continuously varying cell constant *** dependencies of the LiF–DyF3–Dy2O3–Cu2O system conductivity on the melt composition and temperature were examined *** optimal operating conditions for Dy–Cu alloy production were determined via analyses of the electrical conductivity and activation energies for conductance,which were calculated using the Arrhenius *** conductivity of the molten system regularly increases with increasing temperature and decreases with increasing concentration of Dy2O3 or Cu2O or *** activation energy Eκof the LiF–DyF3–Dy2O3 and LiF–DyF3–Cu2O molten-salt systems increases with increasing Dy2O3 or Cu2O *** regression functions of conductance as a function of temperature(t)and the addition of Dy2O3(W(Dy2O3))and Cu2O(W(Cu2O))can be expressed asκ=-2.08435+0.0068t-0.18929W(Dy2O3)-0.07918W(Cu2O).The optimal electrolysis conditions for preparing the Dy–Cu alloy in LiF–DyF3–Dy2O3–Cu2O molten salt are determined to be 2.0wt%≤W(Dy2O3)+W(Cu2O)≤3.0wt%and W(Dy2O3):W(Cu2O)=1:2 at 970 to 1000°C.

关键词： electrical conductivity molten salt Dy–Cu alloy dysprosium oxide cuprous oxide

Fundamental studies for high temperature processing of tungsten leaching residues for alloy formation

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Tungsten 2020年第4期2卷 362-370页

作者： Xu Wang Xiao‑Dong Ma Kun Su chun‑Fa liao Bao‑Jun Zhao Faculty of Materials Metallurgy and ChemistryJiangxi University of Science and TechnologyGanzhouChina The University of Queensland BrisbaneAustralia

The first step in the production of tungsten is to enrich tungsten from two minerals wolframite((Fe,Mn)WO_(4))and scheelite(CaWO_(4))through the leaching *** leaching residue usually contains a certain amount(2-5 wt%)of WO_(3) which is higher than that in the tungsten ore(generally less than 1 wt%).In addition,the leaching residue may also consist of other valuable elements such as Cu,Ta,Nb,Sn,Sc,Mn and *** the phases and their compositions present in the residue is one of the key steps for the efficient *** typical residue sample is carefully analysed by electron probe X-ray microanalysis and X-ray fluorescence.A high-temperature process,which includes pre-reduction at 1000-1100℃and smelting reduction at 1450-1500℃,is proposed to efficiently recover the valuable *** work and thermo-dynamic calculations confirmed that most of the valuable elements can be economically recovered with optimum conditions.

关键词： Tungsten Leaching residue Valuable elements Liquidus temperature Slag

Comparing Operational Efficiency of Mobile Operators in Brazil, Russia, India and China

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China & World Economy 2009年第5期17卷 104-120页

作者： chun-Hsiung liao Diána B.González Department of Communication and Transportation Management and Institute of Telecommunications Management National Cheng Kung University Institute of International Management National Cheng Kung University

Using partial factor productivity and data envelopment analysis approaches, this study measures and compares the operational efficiency of the 10 dominant mobile operators in Brazil, Russia, India and China （BRIC） between 2002 and 2006. The results of data envelopment analysis indicate that the two leading Brazilian mobile operators, Vivo and TIM, are fully efficient throughout the entire period of study, however, Indian mobile operators are the least efficient among BRIC operators. Interestingly, the findings of this study verify that full operational efficiency can be achieved by operators with large revenues, such as China Unicorn, and by other, y with medium and small revenues, such as Hvo, TIM and Oi. Partial faetor productivity demonstrates that 3 of the 4 Brazilian mobile operators, Vivo, TIM and Oi, have remarkable productivity ratios, and that the state-owned operator, China Unicom, has the highest revenue per capital expenditure among BRIC operators. In contrast, Indian mobile operators ＇productivity ratios are generally low compared to other BRIC mobile carriers.

关键词： BRIC data envelopment analysis mobile operator operational efficiency partial factor productivity

Spatial and temporal patterns of amphibian species richness on Tianping Mountain,Hunan Province,China

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Zoological Research 2020年第2期41卷 182-187页

作者： Wen-Bo Zhu chun-Lin Zhao chun-Lin liao Bei Zou Dan Xu Wei Zhu Tian Zhao Jian-Ping Jiang CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan ProvinceChengdu Institute of BiologyChinese Academy of SciencesChengduSichuan 610041China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Southwest China Wildlife Resources Conservation(Ministry of Education) China West Normal UniversityNanchongSichuan 637009China National Nature Reserve of Badagongshan SangzhiHunan 427100China College of Animal Science and Technology Southwest UniversityChongqing 400715China

DEAR EDITOR,Exploring species richness patterns across space and time can help in understanding species distribution and in formulating conservation *** taxa,amphibians are of utmost importance as they are highly sensitive to environmental changes due to their unique life histories(Zhong et al.,2018).Here,we investigated the spatial and temporal patterns of amphibian species richness on Tianping Mountain in ***,we established 10 transects at low to high elevations,and sampled amphibians in April,June,August,and October *** results demonstrated that amphibian species composition and richness varied significantly at both spatial and temporal scales and were associated with gradients of environmental change in microhabitats on Tianping Mountain.

关键词： Hunan Spatial ping

Chemical reactions and thermal stress induced microstructure evolution in 2D-C_(f)/ZrB_(2)-SiC composites

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Journal of Materials Science & Technology 2021年第24期83卷 75-82页

作者： Bo-Wen Chen De-Wei Ni chun-Jing liao You-Lin Jiang Jun Lu Yu-Sheng Ding Hong-Da Wang Shao-Ming Dong State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Structural Ceramics and Composites Engineering Research Center Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China University of Chinese Academy of Sciences Beijing 100049China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Fibers degradation and matrix cracks are very common during fabrication of composites,which seriously reduces the reliability and properties of the *** this work,2 D-C_(f)/Zr B_(2)-Si C composites were fabricated by a joint processing of slurry infiltration and hot *** on thermal kinetics calculation,finite element simulation and detailed microstructure characterization,fibers degradation and matrix cracks formation mechanisms of the composites are discussed and *** impurities including SiO_(2)and ZrO_(2)react with carbon fibers,resulting in formation of Zr C,Si C particles and etching pits on the fibers,which also leads to a strong bonding between the fibers and *** the other hand,thermal expansion mismatch between the fibers and matrix gives rise to serious thermal stress in the *** thermal stress distribution and development are analyzed by finite element simulation,which is in good agreement with the cracks’formation in the *** on the revealed microstructure evolution mechanisms,a potential solution to mitigate fibers degradation and matrix cracks is put forward.

关键词： Ceramic matrix composites Carbon fiber Residual stress