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Application of Lanthanum in High Strength and High Conductivity Copper Alloys

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Journal of Rare Earths 2006年第Z2期24卷 385-388页

作者：周世杰赵秉钧赵桢金鑫 college of Materials sicence and Engineering Southwest Jiaotong University Light-New Materials Science and Technology Co. Ltd.

China is quite poor in argent resource. Roughly 80% of this industrial argent is imported every year. In order to improve the situation, we took advantage of rare earth (RE) mineral resource and successfully developed the non-argent Lanthanum-tellurium-copper alloy as a substitute for industry argent-copper. In our research, we were able to successfully apply rare earth lanthanum to copper alloy. The defects as porosity, inclusion, etc. originating from nonvacuum melting processing were controlled. Fine grain was obtained. Meanwhile, the comprehensive properties of the copper alloy, such as strength, conductivity and thermal conductivity were improved. The research results in increasing conductivity and thermal conductivity by 5% and 15%, respectively, while the tensile strength is increased by 6% higher than Ag-Cu alloy. The anti-electric corrosion property is good, and there is no argent-cadmium steam population originating from the electric arc effect. The addition of lanthanum further reduces the content of oxygen and hydrogen. The optimum quantity of the addition of RE lanthanum in the copper alloy is 0.010% - 0.020% .

关键词： lanthanum copper alloy high strength high conductivity rare earths

Optimizing the key parameter to accelerate the recovery of AMOC under a rapid increase of greenhouse gas forcing

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 39-45页

作者： Haolan Ren Fei Zheng Tingwei Cao Qiang Wang International Center for Climate and Environment Science(ICCES) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina college of Oceanography Hohai UniversityNanjingChina CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of Sciences and Pilot National Laboratory for Marine Science and Technology(Qingdao)QingdaoChina

Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in climate *** studies have suggested that the deviation of model parameters is one of the major factors in inducing inaccurate AMOC *** this work,with a low-resolution earth system model,the authors try to explore whether a reasonable adjustment of the key model parameter can help to re-establish the AMOC after its *** a new optimization strategy,the extra freshwater flux(FWF)parameter is determined to be the dominant one affecting the AMOC’s *** traditional ensemble optimal interpolation(EnOI)data assimilation and new machine learning methods are adopted to optimize the FWF parameter in an abrupt 4×CO_(2) forcing experiment to improve the adaptability of model parameters and accelerate the recovery of *** results show that,under an abrupt 4×CO_(2) forcing in millennial simulations,the AMOC will first collapse and then re-establish by the default FWF parameter ***,during the parameter adjustment process,the saltier and colder sea water over the North Atlantic region are the dominant factors in usefully improving the adaptability of the FWF parameter and accelerating the recovery of AMOC,according to their physical relationship with FWF on the interdecadal timescale.

关键词： Recovery of AMOC 4×CO_(2)forcing Key parameter Parameter estimation Data assimilation Machine learning

Cadmium-Induced Structure Change of Pigment Glands and the Reduction of the Gossypol Content in Cottonseed Kernels

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Phyton-International Journal of Experimental Botany 2020年第2期89卷 315-327页

作者： Ling Li Xuyu Yan Lei Mei Shuijin Zhu college of Life sicence Yan’an UniversityYan’an716000China college of Agriculture and Biotechnology Zhejiang UniversityHangzhou310058China

The risk of cotton production on arable land contaminated with heavy metals has increased in recent *** shows stronger and more extensive resistance to heavy metals,such as cadmium(Cd)than that of other major ***,a potted plant experiment was performed to study Cd-induced alterations in the cottonseed kernel gossypol content and pigment gland structure at maturity in two transgenic cotton cultivars(ZD-90 and SGK3)and an upland cotton standard genotype(TM-1).The results showed that Cd accumulation in cottonseed kernels increased with increasing Cd levels in the *** seed kernel Cd content in plants grown on Cd-treated soils was 10-20 times greater than the amount in the corresponding *** was a significant difference in Cd accumulation in cottonseed kernels at the 400 and 600μM Cd *** accumulation was higher in SGK3 and ZD-90 than in ***,the gossypol content in cottonseed kernels was lower in SGK3 and ZD-90 than in *** was a negative correlation(r=0.550)between Cd accumulation and the gossypol content in cottonseed *** density of cottonseed kernel pigment glands decreased under Cd *** is consistent with the change in gossypol content,which decreased under Cd *** damage of the cultivars ZD-90 and SGK3 from Cd poisoning was relatively low under Cd stress,while TM-1 was seriously affected and exhibited Cd *** studies are necessary to understand the cause of the reduced gossypol content in cotton seeds under Cd stress.

关键词： Cottonseeds cadmium gossypol pigment gland

Synthesis and characterization of Ce_(0.8)Sm_(0.2–x)Pr_xO_(2–δ)(x=0.02–0.08)solid electrolyte materials

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Journal of Rare Earths 2015年第4期33卷 411-416页

作者：林晓敏吕秋月朱丽丽刘晓梅 college of physics Beihua University college of physics Jilin University

Solid electrolytes C%sSmo.2 xPrxO2-δ （x=0.02, 0.04, 0.06, 0.08） were prepared by citric-nitrate method. The microstructure and electrical properties of such materials were examined by X-ray diffraction （XRD）, atomic force microscopy （AFM）, Raman spec- troscopy （Raman）, X-ray photoelectron spectroscopy （XPS） and impedance spectroscopy analyses, Specifically, results from XRD analysis showed that samples calcined at 800 ℃ for 4 h possessed single-phase cubic fluorite structure, and the average grain size was found to be 36--45 nm. Further Raman spectral analysis indicated that oxygen vacancies should be present in the cubic fluorite struc- ture of ***0.08Oe~, and Pr-doping seemed to increase their concentration significantly. AFM images showed that the grain size grew with the increase of Pr substitution. XPS analysis confirmed the existence of oxygen vacancies in the lattice of ***2_~ in which Pr3＋ and Pr4＋ co-existed. AC impedance spectra indicated that the conductivity of ***0.2-xPrx02＋ increased with the increase of Pr-doping but the conduction activation energy decreased. Notably, it appeared that sample ***.12Pro.o802-x （aaoooc=l.21xlO-z S/cm, Ea=0.77 eV） exhibited conductivity superior to ***.2Ol.9 （aro0.c=2.22×10-3 S/cm, Ea= 1.02 eV） because it possessed higher conductivity and lower activation energy. At 600 ℃, the conductivity of ***.12Pr0.0802m was 4.45 times higher than that of the un-doped material.

关键词： Ce0.8Smo.2-xPrx02-δ oxygen vacancy Raman spectroscopy conductivity rare earths

Dynamically controlled optical nonreciprocity of a double-ladder system with spontaneously generated coherence in moving atomic optical lattice

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Chinese physics B 2017年第5期26卷 170-176页

作者：巴诺吴向尧李东飞王丹费金有王磊 college of physics Jilin Normal University college of physics Jilin University

A four-level double-ladder cold atoms system with spontaneously generated coherence trapped in a moving optical lattice is explored to achieve optical nonreciprocity. When spontaneously generated coherence（SGC） is present, the remarkable contrast optical nonreciprocity of light transmission and reflection can be generated at each induced photonic bandgap in the optical lattice with a velocity of a few m/s. However, when the SGC effect is absent, the optical nonreciprocity becomes weak or even vanishing due to the strong absorption. It is found that the optical nonreciprocity is related to the asymmetric Doppler effect in transmission and reflection, meanwhile the degree and position of optical nonreciprocity can be tuned by the SGC effect and the Rabi frequency of the trigger field.

关键词： coherence spontaneously ladder trapped resonant dipole transparency vanishing photonic absolute

Effect of hydrostatic pressure and polaronic mass of the binding energy in a spherical quantum dot

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Chinese physics B 2015年第11期24卷 92-97页

作者： A.Rejo Jeice Sr.Gerardin Jayam K.S.Joseph Wilson Department of physics Annai Velankanni College Department of physics Holy Cross College Departmant of physics Arul Anandar College (Autonomous)

Simultaneous effect of hydrostatic pressure and polaronic mass on the binding energies of the ground and excited states of an on-center hydrogenic impurity confined in a GaAs/GaA1As spherical quantum dot are theoretically investigated by the variational method within the effective mass approximation. The binding energy is calculated as a function of dot radius and pressure. Our findings proved that the hydrostatic pressure led to the decrease of confined energy and the increase of donor binding energy. Conduction band non-parabolicity and the polaron masses are effective in the donor binding energy which is significant for narrow dots not in the confined energy. The maximum donor binding energy achieved by the polaronic mass in the ground and excited states are 2%-19% for the narrow dots. The confined and donor binding energies approach zero as the dot size approaches infinity.

关键词： spherical quantum dot square well confinement confined energies effective mass approximation

Physical properties of hexagonal WN_2 under pressure

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Chinese physics B 2011年第9期20卷 163-170页

作者：李晓凤翟红村付宏志刘中利姬广富 college of physics and Electronic Information Luoyang Normal College Laboratory for Shock Wave and Detonation physics Research Institute of Fluid PhysicsChina Academy of Engineering Physics Mathematics college Luoyang Normal College

A first-principles study on the mechanical stability, elastic and thermodynamic properties of WN2 with P63/mmc and P-6m2 phases are reported using the pseudo potential plane wave method within the generalized gradient approx- imation. The calculated equilibrium parameters are in good agreement with the available theoretical data. A complete elastic tensor and crystal anisotropies of the ultra-incompressible WN2 are determined in the wide pressure range. By the elastic stability criteria, it is predicted that P63/mmc and P-6m2 phases in WN2 are not stable above 175.1 GPa and 170.1 GPa, respectively. Finally, by using the quasiharmonic Debye model, the isothermal and adiabatic bulk modulus, and the heat capacity of WN2 are also successfully obtained.

关键词： density functional theory elasticity thermodynamic properties nitrides

First-principles study of mechanical stability and thermal properties of MNNi_3 (M=Zn,Mg,Al) under pressure

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Chinese physics B 2012年第5期21卷 494-500页

作者：翟红村李晓凤杜军毅姬广富 Mathematics college Luoyang Normal College college of physics and Electronic Information Luoyang Normal College Laboratory for Shock Wave and Detonation physics Research Institute of Fluid physics Chinese Academy of Engineering Physics

The mechanical stability,elastic,and thermodynamic properties of the anti-perovskite superconductors MNNi 3（M=Zn,Mg,Al） are investigated by means of the first-principles *** calculated structural parameters and elastic properties of MNNi 3 are in good agreement with the experimental and the other theoretical *** the elastic constants under high pressure,we predict that ZnNNi 3,MgNNi 3,and AlNNi 3 are not stable at the pressures above 61.2 GPa,113.3 GPa,and 122.4 GPa,*** employing the Debye model,the thermodynamic properties,such as the heat capacity and the thermal expansion coefficient,under pressures and at finite temperatures are also obtained successfully.

关键词： density functional theory elasticity thermodynamic properties

Enhanced structural and magnetic properties of microwave sintered Li–Ni–Co ferrites prepared by sol–gel method

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Chinese physics B 2019年第2期28卷 358-362页

作者： NANDeibam Nilima M Maisnam Sumitra Phanjoubam Department of physics Oriental College Department of physics Oriental CollegeTakyel Department of physics Manipur University

The properties of lithium ferrites are very sensitive to chemical composition, synthesis method, and sintering techniques. Li–Ni–Co ferrites with compositional formula Li_(0.45-0.5x)Ni_(0.1)Co_xFe_(2.45-0.5x)O_4, where 0.00 ≤ x ≤ 0.1 in steps of 0.02 were prepared by chemical sol–gel method and sintered by microwave sintering technique. The x-ray diffraction patterns confirmed the formation of single phase with spinel structure in all the samples. The structural parameter *** constant, crystallite size, and x-ray density for these samples were studied and compared with those measured from samples of similar composition prepared by the sol–gel method and sintered by conventional sintering technique. Enhancement in the magnetic properties like Curie temperature, hysteresis parameters was observed by employing sol–gel synthesis combined with microwave sintering. The results obtained and mechanisms involved are discussed in the paper.

关键词： lithium ferrites sol–gel chemistry magnetic properties x-ray diffraction