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Journal of Rare Earths 2018年第11期36卷 1190-1197页

作者： Qianlin Chen xin Ma xin zhang Yunqi Liu Ming Yu School of Chemistry and Chemical Engineering Cuizhou University Guiyang 550003 China Guizhou Engineering & Technology Research Center of Clean Production in Phosphorus Chemical Industry Guiyang 550003 China

It is very significant to recover rare earths （REs） from wet-process phosphoric acid, in terms of extraction rate and selectivity, the current carrier di（2-ethlhexly） phosphate （D2EHPA） out there is still inferior. Based on this question, our team modified D2EHPA to synthesize new extractants. This paper presents a comprehensive study on the extraction of rare earth ions （RE3＋） from phosphate leach solution using emulsion liquid membrane （ELM） in concentrated nitric acid medium. The ELM system is made up of （RO）2P（O）OPh-COOH as carrier, polyisocrotyl succinimide （T154） as surfactant, sulfonated kerosene as diluent, phosphoric acid （H3PO4） as stripping solution. Different chemical parameters such as type and concentration of carrier, surfactant, stripping solution, volume ratio of oil phase to internal phase, and volume ratio of emulsion ratio to external phase were analyzed. The extraction of RE^3＋ was evaluated by the yield of extraction. In addition, the demulsification process was also investigated. The proposed method of ELM using （RO）2P（O）OPh-COOH as carrier can he expected to provide an efficient, simplify operation, and facilitated method for extractine RE^3＋.

关键词： Emulsion liquid membrane Rare earth Nitric acid Extraction rate Phosphate rock Stripping solution

Precise asymptotics in the law of the logarithm for random fields in Hilbert space

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 651-659页

作者： FU Ke-ang zhang Li-xin Department of Mathematics Zhejiang University Hangzhou 310027 China

Consider the positive d-dimensional lattice Z^d（d≥2） with partial ordering ≤, let {XK; K∈Z＋^d} be i.i.d, random variables taking values in a real separable Hilbert space （H, ｜｜·｜｜） with mean zero and covariance operator ∑ and set partial sums SN =∑K≤nXK,K,N∈Z＋^d. Under some moment conditions, we obtain the precise asymptotics of a kind of weighted infinite series for partial sums SN as ε↓ by using the truncation and approximation methods. The results are related to the convergence rates of the law of the logarithm in Hilbert space, and they also extend the results of （Gut and Spataru, 2003）.

关键词： The law of the logarithm Random field Hilbert space. Tail probabilitv. Truncation method

Synthesis and Characterization of Highly Efficient Photoluminescence Gd doping Hexagonal CePO4 (One-dimensional Nanowires)

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Chinese Journal of Structural Chemistry 2020年第8期39卷 1515-1521,1361页

作者： zhang xin-Qi Instrumentation Analysis and Research Center Fuzhou UniversityFuzhou 350108China

Rare earth phosphates have been used extensively in luminescent *** Ce1-xGdxPO4 with crystal field manipulation was successfully synthesized using a hydrothermal *** photoluminescence emission intensity of hexagonal CePO4 was obviously enhanced by the crystal structure manipulation with gadolinium ions *** to pure CePO4,the intensity photoluminescence was enhanced about 15 folds with x=*** effect of gadolinium doping was systematically investigated by X-ray diffraction,transmission electron microscopy,X-ray photoelectron spectroscopy and photoluminescence *** field asymmetry can be effectively tuned by different amount of Gd^3+codoping,and the crystal field asymmetry is conductive to electron population of high energy level of Ce^3+*** material has potential applications in optics,electronics fields,and so ***,the method can be extended to another kind of high performance photoluminescence materials preparation.

关键词： rare earth hydrothermal photoluminescence gadolinium dopant crystal field

STRONG LIMIT THEOREMS FOR EXTENDED INDEPENDENT RANDOM VARIABLES AND EXTENDED NEGATIVELY DEPENDENT RANDOM VARIABLES UNDER SUB-LINEAR EXPECTATIONS

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Acta Mathematica Scientia 2022年第2期42卷 467-490页

作者： Li-xin zhang School of Mathematical Sciences Zhejiang UniversityHangzhou 310027China

Limit theorems for non-additive probabilities or non-linear expectations are challenging issues which have attracted a lot of interest *** purpose of this paper is to study the strong law of large numbers and the law of the iterated logarithm for a sequence of random variables in a sub-linear expectation space under a concept of extended independence which is much weaker and easier to verify than the independence proposed by Peng[20].We introduce a concept of extended negative dependence which is an extension of the kind of weak independence and the extended negative independence relative to classical probability that has appeared in the recent *** tools such as moment inequality and Kolmogorov’s exponential inequality are established for these kinds of extended negatively independent random variables,and these tools improve a lot upon those of Chen,Chen and Ng[1].The strong law of large numbers and the law of iterated logarithm are also obtained by applying these inequalities.

关键词： Sub-linear expectation capacity extended negative dependence Kolmogorov’s exponential inequality laws of the iterated logarithm law of large numbers

IMPLEMENTATION OF MIXED METHODS AS FINITE DIFFERENCE METHODS AND APPLICATIONS TO NONISOTHERMAL MULTIPHASE FLOW IN POROUS MEDIA

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Journal of Computational Mathematics 2006年第3期24卷 281-294页

作者： zhang-xin Chen Xi-jun Yu Center for Scientific Computation Box 750156 Southern Methodist University Dallas TX 75275-0156 USA Research Center for Science Xi'an Jiaotong University Xi'an 710049 China Center for Advanced Reservoir Modeling and Simulation College Vof Engineering'PekingI University China Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics Beijing 100088 China

In this paper we consider mixed finite element methods for second order elliptic problems. In the case of the lowest order Brezzi-Douglas-Marini elements （if d = 2） or Brezzi- Douglas-Duran-Fortin elements （if d = 3） on rectangular parallelepipeds, we show that the mixed method system, by incorporating certain quadrature rules, can be written as a simple, cell-centered finite difference method. This leads to the solution of a sparse, positive semidefinite linear system for the scalar unknown. For a diagonal tensor coefficient, the sparsity pattern for the scalar unknown is a five point stencil if d = 2, and seven if d = 3. For a general tensor coefficient, it is a nine point stencil, and nineteen, respectively. Applications of the mixed method implementation as finite differences to nonisothermal multiphase, multicomponent flow in porous media are presented.

关键词： Finite difference Implementation Mixed method Error estimates Superconvergence Tensor coefficient Nonisothermal multiphase Multicomponent flow Porousmedia.

“Always learn today, stand ready to act tomorrow”--Po Tien: A pioneer of Virology in China

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Protein & Cell 2022年第2期13卷 79-81页

作者： xin zhang Huan Liu Institute of Biophysics Chinese Academy of SciencesBeijing 100101China Wuhan Institute of Virology Chinese Academy of SciencesWuhan 430071China Chinese Center for Disease Control and Prevention Beijing 102206China State Key Laboratory of Virology Wuhan 430072China

There is a scientist who was engaged in truly great achievements of modern virology in *** first successfully applied viral satellite RNA as a biological control agent to prevent viral plant diseases(Tien,1996),concluding that ribozyme-mediated high resistance against potato spindle tuber viroid in transgenic potatoes could reduce the pathogen to an undetectable level(Yang et al.,1997).He isolated a HBV-specific peptide associated with heat-shock protein gp96 from liver cancer tissues of HBV-infected patients for the first time(Meng et al.,2001).

关键词： diseases today

Preparation and thermoelectric transport properties of Ba-, La- and Ag- doped Ca3Co4O9 oxide materials

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Journal of Rare Earths 2013年第8期31卷 778-783页

作者： zhang Feipeng LU Qingmei LITingxian zhang xin zhang Jiuxing SONG Xiaoyan Department of Applied Sciences Henan University of Urban Construction Pingdingshan 467036 China Key Laboratory of Advanced Functional Materi- als Chinese Ministry of Education College of Materials Science and Engineering Beijing University of Technology Beijing 100124 China College of Phys- ics and Electrical Engineering Anyang Normal University Anyang 455002 China

The Ba-, La- and Ag-doped polycrystalline Ca2.9M0.1Co4O9 （M=Ca, Ba, La, Ag） thermoelectric bulk samples were pre- pared via citrate acid sol-gel synthesis method followed by spark plasma sintering technique. The bulk samples were characterized and analyzed with regard to their phase compositions, grain orientations as well as microstructures. The high temperature thermoelec- tric transport properties of the bulk samples were studied in detail. All bulk samples were found to be single-phased with modified body texture. The electrical resistivity was modulated as a result of carrier concentration modification, however the carrier transport process was not influenced; the Seebeck coefficient was deteriorated simultaneously. The total thermal conductivity was remarkably reduced, on account of the decreasing of phonon thermal conductivity. The thermoelectric properties of the Ba-, La-, and Ag-doped bulk samples were optimized, and the Ba-doped Ca2.9Ba0.1Co4O9 system was found to have the highest dimensionless figure of merit ZT0.20 at 973 K, which was remarkably higher than that of the un-doped sample.

关键词： Ca3Co4O9 oxide Ca-site doping thermoelectric transport properties rare earths

Autophagy in mitotic animal cells

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Science Bulletin 2016年第2期61卷 105-107页

作者： Zhiyuan Li xin zhang High Magnetic Field Laboratory Chinese Academy of Sciences

Mitosis is a highly dynamic cellular event that involves high energy consumption and active membrane *** is a process that cells digest their cellular contents to provide energy and nutrients to maintain *** now,whether autophagy persists during mitosis is still *** most dividing animal cells,the whole cell cycle can be divided into about 20 h of interphase and 1–2 h

关键词：有丝分裂过程动物细胞自噬体内平衡营养物质高耗能 ing 高活性

Gamma-phase influence on shape memory properties in Ni-Mn-Co-Ga-Gd high-temperature shape memory alloys

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Acta Metallurgica Sinica(English Letters) 2018年第5期31卷 471-476页

作者： Wei zhang xin zhang Qian Wang Qing-Suo Liu School of Materials Science and Engineering Tianjin University of Technology

The effect of γ-phase on two-way shape memory effect（TWSME） of polycrystalline Ni56Mn25-xCoxGa18.9Gd0.1 alloys was investigated. The results show that an appropriate amount of ductile γ-phase significantly enhances the TWSME. The largest TWSME of 1.4% without training is observed in N（56Mn21Co4Ga18.9Gd0.1 alloy, and this value is increased to 2.0% after thermomechanical training. The as-trained TWSME decays over the first five thermal cycles and then reaches a stable value as the number of cycles further increasing. Only the degradation of 0.2% is observed after 100 thermal cycles. The better TWSME and thermal stability are ascribed to the stable extra stress field formed by the plastically deformed γ-phase.

关键词： Shape memory alloys Ni-Mn-Ga alloys Thermomechanical training Second phase Two-way shape memory effect

Room-temperature magnetoresistance in a-C:Co/Si system

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Science China(Physics,Mechanics & Astronomy) 2011年第7期54卷 1213-1217页

作者： zhang xin zhang XiaoZhong WAN CaiHua Key Laboratory of Advanced Materials Department of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Beijing National Center of Electron Microscopy Beijing 100084China

Three types of a-C:Co/Si samples were fabricated using the pulsed laser deposition: Co2-C98/8i with Co dispersed in the a-C film, Co2-C98/Si with Co segregated at the interface, and a-C/Co/Si with Co continuously distributed at the a-C/Si interface. Both types of Co2-C98/Si samples had the positive bias-voltage-dependent magnetoresistance (MR) at 300 K, and all MRs had saturated behavior. The study on the electrotransport properties indicated that the MR appeared in the diffusion current region, and the mechanism of MR was proposed to be that the applied magnetic field and local random magnetic field caused by the superparamagnetic Co particles modulate the ratio of singlet and triplet spin states, resulting in the MR effect. In addition, the very different physical and structural properties of all samples revealed that Co played a crucial role in the room-temperature positive MR of a-C:Co/Si system.

关键词： magnetoresistance carbon film pulsed laser deposition