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Extraction of metals from complex sulfide nickel concentrates by low-temperature chlorination roasting and water leaching

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International Journal of Minerals,Metallurgy and Materials 2017年第4期24卷 377-385页

作者： Cong Xu Hong-wei Cheng Guang-shi Li chang-yuan lu Xiong-gang lu Xing-li Zou Qian Xu State Key Laboratory of Advanced Special Steel & School of Materials Science and Engineering Shanghai University Shanghai 200072 China

The recovery of valuable metals from complex sulfide concentrates was investigated via chlorination roasting followed by water leaching. A reaction process is proposed on the basis of previous studies and the results of our preliminary experiments. During the process, various process parameters were studied, including the roasting temperature, the addition of NH4Cl, the roasting time, the leaching time, and the liquid-to-solid ratio. The roasted products and leach residues were characterized by X-ray diffraction and vibrational spectroscopy. Under the optimum condition, 95% of Ni, 98% of Cu, and 88% of Co were recovered. In addition, the removal of iron was studied in the water leaching stage. The results demonstrate that this process provides an effective approach for extracting multiple metals from complex concentrates or ores. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg.

关键词： Calcination Chemicals removal (water treatment) Chlorination Leaching Metal recovery Nickel Rare earths Sulfur compounds Temperature X ray diffraction

Strong light–matter interaction in ZnO microcavities

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Light(Science & Applications) 2013年第1期2卷 128-134页

作者： Ying-Yu Lai Yu-Pin Lan Tien-chang lu Department of Photonics National Chiao Tung UniversityHsinchu 300

The strong light–matter interaction in ZnO-embedded microcavities has received great attention in recent years,due to its ability to generate the robust bosonic quasiparticles,exciton-polaritons,at or above room *** review introduces the strong coupling effect in ZnO-based microcavities and describes the recent progress in this *** addition,the report contains a systematic analysis of the room-temperature strong-coupling effects from relaxation to polariton *** stable room temperature operation of polaritonic effects in a ZnO microcavity promises a wide range of practical applications in the future,such as ultra-low power consumption coherent light emitters in the ultraviolet region,polaritonic transport,and other fundamental of quantum optics in solid-state systems.

关键词： microcavity polariton strong coupling ZnO

Effect of Waterlogged and Aerobic Incubation on Enzyme Activities in Paddy Soil

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Pedosphere 2006年第4期16卷 532-539页

作者： WANG Xiao-chang lu Qin Department of Tea Science College of Agriculture and Biotechnology Zhejiang University Hangzhou 31002g （China） Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）

An incubation experiment with soil water content treatments of 0.15 （W1）, 0.20 （W2）, and 0.40 （W3） g g^-1 soil was carried out for two months to investigate the activities of important enzymes involved in C, N, P, and S cycling in a paddy soil from the Taihu Lake region, China, under waterlogged and aerobic conditions. Compared with air-dried soil, waterlogging resulted in a significant decrease （P ≤ 0.05） of fluorescein diacetate （FDA） and /3-D-glucosidase activities, and this effect was enhanced with increasing waterlogging time. Waterlogging also significantly inhibited （P ≤ 0.05） arylsulfatase as well as alkaline and acid phosphatase activities, but did not decrease the activities with the increase in waterlogging time. Short-term waterlogging did not affect urease activity, but prolonged waterlogging decreased it markedly. In contrast, the aerobic incubation （W1 and W2 treatments） significantly increased （P ≤ 0.05） FDA, alkaline phosphatase, and /3-D-glucosidase activities. With aerobic treatments the activities of FDA and alkaline phosphatase increased with incubation time, whereas /3-D-glucosidase activity decreased. A significant difference （P ≤ 0.05） was usually observed between the W1 and W2 treatments for the activities of FDA as well as alkaline and acid phosphatase; however,/3-D-glucosidase and urease were usually not significant （P ≤ 0.05）. No activity differences were observed between waterlogging and aerobic incubation for arylsulfatase and urease.

关键词： aerobic incubation enzyme activity paddy soil waterlogging

New upper limits on deviation from the inverse-square law of gravity in the solar system:a Yukawa parameterization

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Research in Astronomy and Astrophysics 2014年第2期14卷 139-143页

作者： Zi-Wei Li Sheng-Feng Yuan chang lu Yi Xie School of Astronomy and Space Science Nanjing University Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityMinistry of Education

New physics beyond the standard model of particles might cause deviation from the inverse-square law of gravity. In many theoretical models of modified gravity, it is parameterized by the Yukawa correction to the Newtonian gravitational force in terms of two parameters α and λ. Here α is a dimensionless strength parameter and A is a length scale. Using the supplementary advances in perihelia provided by INPOP10a and EPM2011 ephemerides, we obtain new upper limits on the deviation from the inverse-square law when the uncertainty of the Sun＇s quadrupole moment is taken into account. We find that INPOP10a yields the upper limits as α =- 3.1× 10-11 and λ= 0.15 au, and EPM2011 gives α = 5.2 × 10-11 and λ=- 0.21 au. In both of them, α is at least 10 times less than the previous results.

关键词： gravitation -- ephemerides -- celestial mechanics

Cation-π and electrostatic interactions co-driven assembly of two-dimensional heteropore supramolecular polymers with rapid iodine capture capability

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Science China Chemistry 2023年第7期66卷 2070-2082页

作者： Hongbin Huo Xuedong Xiao lu chang Xuanchen Xiong Menghan Shi Jingxia Wang Wei Tian Shaanxi Key Laboratory of Macromolecular Science and Technology Xi’an Key Laboratory of Hybrid Luminescent Materials and Photonic DeviceKey Laboratory of Material Physics and Chemistry under Extraordinary ConditionsMinistry of EducationSchool of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

Constructing two-dimensional(2D)supramolecular polymers with complicated hierarchical porosity significantly contributes to developing effective strategies to control delicate self-assembly architectures,thus facilitating the fabrication of advanced 2D organic functional ***,we report utilizing cooperative cation-πand electrostatic interactions to construct a series of robust 2D heteropore supramolecular polymers(2D HPSPs)with hierarchical pore structures,in which hexagonal and rectangular pores are alternately and periodically arranged,and the pore sizes can be finely ***,the as-prepared 2D HPSPs exhibit excellent iodine(I_(2))capture rate(a maximum K80%value is 2.25 g h^(-1)),and present a novel mechanism involving transport-adsorption spatiotemporal separation for rapid I_(2)*** this mechanism,the transport of free I_(2)is first conducted in large hexagonal pores,and then I_(2)can be preferentially adsorbed in small rectangular pores,thereby preventing the transfer channels from blocking and greatly improving the adsorption kinetics.

关键词： supramolecular polymers heteropore two-dimensional iodine capture cation-πinteraction

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Ion thruster accelerator grid erosion mechanism under extreme conditions of cylindrical erosion and chamfer erosion

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Chinese Journal of Aeronautics 2023年第6期36卷 128-139页

作者： Guangqing XIA Jiahui LI chang lu Hai GENG Vladimir A.SAETCHNIKOV Juan LI Yanlong WANG State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of TechnologyDalian 116024China Key Laboratory of Advanced Technology for Aerospace Vehicles of Liaoning Province Dalian University of TechnologyDalian 116024China Collaborative Innovation Center of Micro&Nano Satellites of Hebei Province North China Institute of Aerospace EngineeringLangfang 065000China Science and Technology on Vacuum Technology and Physics Laboratory Lanzhou Institute of PhysicsLanzhou 73000China Physics and Aerospace Technology Department Belarusian State UniversityMinsk 220030Belarus

In this paper,the abnormal experimental phenomenon on barrel erosion under extreme working conditions in the ultra-long life experiment(>10000 h)of ion thruster ion optics is studied by the Immersed-Finite-Element Particle-In-Cell Monte-Carlo-Collision(IFE-PIC-MCC)method and the grid erosion evaluation *** transport process of beam ions and Charge Exchange(CEX)ions in the grid system,and the characteristics and mechanisms of the aperture barrel erosion under extreme erosion conditions(*** cylindrical erosion and chamfer erosion)were systematically *** to the advantage of the IFE method for dealing with complex boundaries in structured mesh,the aperture barrel erosion morphology of the accelerator grid is reconstructed accurately based on the experimental *** results show that,with the evolution of working conditions,the mechanism of the aperture barrel erosion changes significantly,which relies heavily on the accelerator grid *** change of the accelerator grid aperture barrel morphology has a significant effect on the behavior of CEX ions,and only affects the local electric field distribution,but has no effect on the upstream plasma *** the erosion progresses,the erosion position moves downstream along the grid aperture axis direction,and the erosion range becomes *** of the erosion phase,the erosion rate of the CEX ions located downstream of the decelerator grid is the *** erosion rate is related to the mean incident energy and angle,and their variation is closely related to the position and trajectory of CEXions.

关键词： Accelerator grid Charge Exchange(CEX)ions Erosion IFE-PIC-MCC Ion propulsion

Spatial weight matrix in dimensionality reduction reconstruction for microelectromechanical system-based photoacoustic microscopy

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Visual Computing for Industry,Biomedicine,and Art 2020年第1期3卷 247-256页

作者： Yuanzheng Ma chang lu Kedi Xiong Wuyu Zhang Sihua Yang MOE Key Laboratory of Laser Life Science&Institute of Laser Life Science College of BiophotonicsSouth China Normal UniversityGuangzhou 510631China Guangdong Provincial Key Laboratory of Laser Life Science College of BiophotonicsSouth China Normal UniversityGuangzhou 510631China

A micro-electromechanical system(MEMS)scanning mirror accelerates the raster scanning of optical-resolution photoacoustic microscopy(OR-PAM).However,the nonlinear tilt angular-voltage characteristic of a MEMS mirror introduces distortion into the maximum back-projection ***,the size of the airy disk,ultrasonic sensor properties,and thermal effects decrease the ***,in this study,we proposed a spatial weight matrix(SWM)with a dimensionality reduction for image *** three-layer SWM contains the invariable information of the system,which includes a spatial dependent distortion correction and 3D *** employed an ordinal-valued Markov random field and the Harris Stephen algorithm,as well as a modified delay-and-sum method during a time *** results from the experiments and a quantitative analysis demonstrate that images can be effectively reconstructed using an SWM;this is also true for severely distorted *** index of the mutual information between the reference images and registered images was 70.33 times higher than the initial index,on ***,the peak signal-to-noise ratio was increased by 17.08%after 3D *** accomplishment offers a practical approach to image reconstruction and a promising method to achieve a real-time distortion correction for MEMS-based OR-PAM.

关键词： Photoacoustic microscopy Spatial weight matrix Dimensionality reduction Distortion correction Mutual information

Separation of Gold Nanorods Using Density Gradient Ultracentrifugation

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Nano Research 2011年第8期4卷 723-728页

作者： Shuai Li Zheng chang Junfeng Liu lu Bai Liang luo Xiaoming Sun State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China

High quality gold nanorods （NRs） with a monodisperse size and aspect ratio are essential for many applications. Here, we describe how nearly monodisperse gold NRs can be separated from polydisperse samples using density gradient ultracentrifugation. Size and dimension analysis by transmission electron microscopy （TEM） and absorption spectroscopy revealed that the Au NRs were separated mainly as a function of their aspect ratio The surface-enhanced Raman scattering （SERS） activity of Au NRs with lower aspect ratio is notably stronger than that of NRs with higher aspect ratio under 633 nm laser excitation, due to the size-dependent absorption of the longitudinal plasmon band. The separation approach provides a method to improve the quality of NRs produced by large scale synthetic methods.

关键词： Au nanorods aspect ratio density gradient separation surface-enhanced Raman scattering (SERS)

First-principles study on the mechanical properties of M2CT2（M=Ti,Zr,Hf;T=O,F,OH） MXenes

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Nuclear Science and Techniques 2019年第11期30卷 60-71页

作者： Yu-chang lu Cui-Lan Ren chang-Ying Wang Ya-Ru Yin Han Han Wei Zhang Ping Huai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Interfacial Physics and Technology Chinese Academy of SciencesShanghai 201800China changzhou Institute of Technology Changzhou 213032China Center of Shanghai Light Source Shanghai Advanced Research InstituteShanghai 201204China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

Two-dimensional(2D)transition metal carbides known as MXenes belong to a new branch of 2D material family,and their fundamental properties vary with their compositions and surface *** this study,the structural and ideal mechanical properties of M2C-type MXenes and their functionalized M2CT2 MXenes(M=Ti,Zr,Hf;T=O,F,OH)were systematically examined via first-principles *** stress–strain curves of the MXenes under homogenous biaxial and uniaxial tension are identified,and the fundamental quantities(e.g.,Young’s modulus,in-plane stiffness,and Poisson’s ratio)are *** significantly higher strength and extended critical strains,the M2CO2 MXenes exhibit optimal flexibility when compared with that of M2C,M2CF2,and M2C(OH)***,Hf2CT2 exhibits optimal tensile performance under uniaxial or biaxial tension when compared to that of Ti2CT2 and *** Young’s modulus,in-plane stiffness,and Poisson’s ratio of MXenes with different surface functionalization increase in a sequence corresponding to OH\F\***,the effects of vacancy on the mechanical properties of MXenes are further explored and indicate that vacancy can significantly weaken the tensile properties of MXenes that are ***,vacancy also results in a certain anisotropy of stress along armchair and zigzag directions even under the biaxial tension condition.

关键词： MXenes Mechanical properties Vacancy First-principles study