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Role of trivalent antimony in the removal of As, Sb, and Bi impurities from copper electrolytes

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International Journal of Minerals,Metallurgy and Materials 2013年第1期20卷 9-16页

作者： fa-xin xiao Dao Cao Jian-wei Mao xiao-ni Shen Feng-zhang Ren School of Materials Science and engineering Henan University of Science and Technology Henan Key Laboratory of Advanced Nonferrous Metal Materials

The role of trivalent antimony was investigated in removing As, Sb, and Bi impurities from a copper electrolyte. Puri- fication experiments were carried out by adding a various concentrations of Sb（III） ions in a synthetic electrolyte containing 185 g/L sulfuric acid, 45 g/L Cu2＋, 10 g/L As, and 0.5 g/L Bi under stirring at 65℃ for 2 h. The electrolyte was filtered, and the structure, morphology and composition of the precipitate were analyzed by means of chemical analysis, scanning electron mi- croscopy （SEM）, X-ray diffraction （XRD）, transmission electron microscopy （TEM）, and IR spectroscopy. The precipitate is composed of irregular lumps which are agglomerated by fine dendritic and floccus particles, and it mainly consists of As, Sb, Bi, and O elements. Characteristic bands in the IR spectra of the precipitate are As-OX （X=As, Sb, Bi）, Sb-OY （Y=Sb, Bi）, O-As-O1 As-OH, Sb-OH, and O-H. The precipitate is a mixture of microcrystalline SbAsQ, （Sb,As）203, and amorphous phases. As, Sb, and Bi impurities are effectively removed from the copper electrolyte by Sb（III） ions attributing to these pre- cipitates.

关键词： copper metallurgy electrorefining electrolytes impurities removal antimony arsenic bismuth

Creep rupture behavior and microstructural evolution of modified 9Cr-1Mo heat-resistant steel

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Journal of Iron and Steel Research International 2018年第12期25卷 1303-1310页

作者： fa-cai Ren He Wang xiao-ying Tang Fei Chen Shanghai Institute of Special Equipment Inspection and Technical Research Shanghai 200062China Capital Aerospace Machinery Corporation Limited Beijing 100076China National Engineering Research Centre of Die &Mold CAD Shanghai Jiao Tong UniversityShanghai 200030China

High-temperature creep rupture behavior of modified 9Cr-lMo steel used for steam cooler was investigated at temperature of 838 and 923 K and stress ranging from 100 to 250 *** on the analysis of creep rate-time curves,it is found that the creep rupture life decreases with the increase in the applied stress and *** creep damage tolerance factor has been identified as a value of *** the normalized and tempered condition,the studied steel shows typical martensitic microstructure with Cr-rich M23C6 and Nb-or V-rich MX ***,the Laves phase has been found along the grain *** fracture morphology characterized by field emission scanning electron microscope is adopted to reveal the creep failure *** investigated results indicate the occurrence of the transgranular fracture under all the creep test conditions.

关键词： Creep rupture behavior Modified 9Cr-1Mo steel Microstructural evolution Fractography

On Generic Extensions of Representations of a Dynkin Quiver of Type D

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Acta Mathematica Sinica,English Series 2005年第3期21卷 613-622页

作者： xiao qin DENG Jiang Rong CHEN School of Sciences Beijing Jiaotong University Beijing 100044 P. R. China Department of Mathematics Beijing Normal University Beijing 100875 P. R. China

The notion of generic extensions of representations of a Dynkin quiver plays a big role in the study of the structure of the corresponding quantum group. In this paper, we describe the generic extensions of a simple representation by any representation and that of any representation by a simple representation of a Dynkin quiver Q of type D.

关键词： Dynkin quiver Representation Generic extension

Interference Coordination for FD-MIMO Cellular Network with D2D Communications Underlaying

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China Communications 2018年第12期15卷 75-88页

作者： xiao Li Nana qin Tingting Sun National Mobile Communications Research Laboratory Southeast University

In this paper, we investigate the interference coordination for downlink full-dimension multiple-input multiple-output(FD-MIMO) systems with device-to-device(D2 D) communications underlaying. With three-dimensional(3 D) beamforming transmission applied for cellular users(CUEs), an approximation of the interference to signal ratio for CUEs is derived, and a coordination strategy is proposed to mitigate the interference from D2 D pairs to CUEs. Based on the lower bound of the interference to signal ratio for D2 D pairs, we propose coordination strategies for D2 D pairs to mitigate the interference caused by base station(BS) and the interference between D2 D pairs. The proposed strategies require only some statistical channel state information(CSI) of each user and the reduced-dimensional effective CSI of a few CUEs and D2 D pairs. Simulation results show that the proposed coordination strategy performs well in terms of achieving good tradeoff between the achievable rate of CUEs and D2 D pairs.

关键词： D2D FD-MIMO 3D beamforming interference coordination

Stability of Rarefaction Wave for Compressible Navier-Stokes Equations on the Half Line

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Acta Mathematicae Applicatae Sinica 2016年第1期32卷 175-186页

作者： Li-hua MIN xiao-hong qin School of Science Nanjing University of Posts and Telecommunications Department of Mathematics Nanjing University of Science and Technology

This paper is concerned with the large-time behavior of solutions to an initial-boundary-value problem for full compressible Navier-Stokes equations on the half line（0,∞）,which is named impermeable wall *** is shown that the 3-rarefaction wave is stable under partially large initial perturbation if the adiabatic exponent γ is close to *** partially large initial perturbation means that the perturbation of absolute temperature is small,while the perturbations of specific volume and velocity can be *** proof is given by the elementary energy method.

关键词： compressible Navier-Stokes equations rarefaction wave stability

Arabidopsis SMALL ORGAN_4, a homolog of yeast NOP_(53), regulates cell proliferation rate during organ growth

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Journal of Integrative Plant Biology 2015年第10期57卷 810-818页

作者： xiao-Ran Zhang Zhixiang qin xiao Zhang Yuxin Hu Key Laboratory of Plant Molecular Physiology Institute of Botany the Chinese Academy of Sciences University of Chinese Academy of Sciences National Center for Plant Gene Research

Cel proliferation is a fundamental event essential for plant organogenesis and contributes greatly to the final organ size. Although the control of cel proliferation in plants has been extensively studied, how the plant sets the cel number required for a single organ is largely elusive. Here, we describe the Arabidopsis SMALL ORGAN 4 (SMO4) that functions in the regulation of cell proliferation rate and thus final organ size. The smo4 mutant exhibits a reduced size of organs due to the decreased cell number, and further analysis reveals that such phenotype results from a retardation of the cell cycle progression during organ development. SMO4 encodes a homolog of NUCLEOLAR PROTEIN 53 (NOP53) in Saccharomy-ces cerevisiae and is expressed primarily in tissues undergoing cel proliferation. Nevertheless, further complementation tests show that SMO4 could not rescue the lethal defect of NOP53 mutant of S. cerevisiae. These results define SMO4 as an important regulator of cell proliferation during organ growth and suggest that SMO4 might have been evolutionarily divergent from NOP53.

关键词： Arabidopsis cell proliferation NOP53 organ size SMO4

Experimental and numerical investigation of the impacts of rotor tip-rake on excitation forces of pump-jet propulsors

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Journal of Hydrodynamics 2024年第1期36卷 142-157页

作者： Xue-qin Ji xiao-song Zhang Chen-jun Yang xiao-qian Dong State Key Laboratory of Ocean Engineering Marine Numerical Experiment CentreSchool of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China CSSC Shanghai Marine Energy Saving Technology Co. Ltd.Shanghai200011China China Ship Scientific Research Center Shanghai Branch Shanghai200011China

The tip-clearance flow in a pump-jet propulsor exerts great impacts on the fluctuating pressures and resultant unsteady forces,which are important sources of structural vibrations and radiated noise *** blade geometry close to the tip is an important factor determining the vortex strength in the tip-clearance *** the open-water condition,the effects of raking the rotor tips on the duct-surface fluctuating pressures and the resultant unsteady forces acting on different components of the propulsor are investigated via physical model experiments and the numerical solution of Reynolds-averaged Navier-Stokes(RANS)equations coupled with the SST k-ωturbulence *** measured and simulated results of hydrodynamic pressures are consistent to each other,and the simulated flows help better understand why the fluctuating pressures change with the tip *** strong fluctuations of duct-surface pressures are caused by intensive tip separation *** duct-surface pressure fluctuations are effectively reduced by using the rake distribution near the tip towards blade back side and,for the combination of the five-bladed rotor and the seven-bladed stator,the resultant unsteady horizontal(and vertical)forces acting on the duct and stator are also reduced;while increasing rake leads to negative effect on pressure fluctuations and unsteady horizontal(and vertical)forces acting on all the components of the propulsor.

关键词： Pump-jet tip-clearance tip-rake fluctuating pressures excitation forces

Performance and Kinetics Studies on Selective Catalytic Reduction of NOx with NH_3 over MnO_x-WO_3/TiO_2 Catalyst

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Chemical Research in Chinese Universities 2010年第6期26卷 1002-1006页

作者： WU Bi-jun xiao Ping LIU xiao-qin Guodian Science and Technology Research Institute Nanjing 210031 P R. China Chemical Engineering Institute Nanjing University of Technology Nanjing 210009 P. R. China

The catalytic activities of MnOx-WO3/TiO2 for selective catalytic reduction（SCR） of NO with NH3 were investigated in a wide range of temperature and reaction *** yielded a NOx conversion of 80.3%—99.6% and a N2 product selectivity of 100%—98.7% during 100 °C to 350 °C at gas hourly space velocity（GHSV）=18900 *** the presence of 0.01% SO2 and 6% H2O at 120 °C,the NOx conversion can maintain 98.5%.At 300 °C and with 0.07% SO2 in reactant stream,the NOx conversion stabilized at 99% as high as the commercial V-W/TiO2 catalyst＇s *** steady-state kinetics study shows that O2 played a promoting *** the presence of less than 1.5% O2,NOx conversion can increase sharply with the increase of O2 *** reaction order was zero with respect to NH3 and first with respect to NO with excess O2 and *** kinetics active energy（Ea） of Mn-W/TiO2 was calculated to be 6.24 kJ/mol according to the kinetic experiment at various temperatures,much lower than those of other catalysts reported in the ***-W/TiO2 is an excellent catalyst for SCR of NO with NH3 by now.

关键词： Selective catalytic reduction of NO with NH3 MnOx-WO3/TiO2 Performance Kinetics

Some additive results on Drazin inverse

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Applied Mathematics(A Journal of Chinese Universities) 2015年第4期30卷 479-490页

作者： LIU xiao-ji qin xiao-lan Julio Benítez faculty of Science Guangxi University for Nationalities Universidad Politécnica de Valencia Instituto de Matemática Multidisciplinar

In this paper, we investigate additive results of the Drazin inverse of elements in a ring R. Under the condition ab = ha, we show that a ＋ b is Drazin invertible if and only if aaD （a ＋ b） is Drazin invertible, where the superscript D means the Drazin inverse. Furthermore we find an expression of （a ＋ b）D. As an application we give some new representations for the Drazin inverse of a 2 × 2 block matrix.

关键词： Drazin inverse ring block matrix.