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Synthesis and characterization of aluminum and Al/REE pillared clays and supported palladium catalysts for benzene oxidation

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Journal of Rare Earths 2011年第1期29卷 52-57页

作者：左树锋周仁贤齐陈泽 institute of applied Chemistry Shaoxing University institute of Catalysis Zhejiang University

Volatile organic compounds （VOCs） are considered as a major pollutant in indoor and outdoor air. More stringent environmental regulations have been implemented in order to reduce the VOC emissions. One of the techniques available for destructive removal of VOCs is catalytic oxidation. In the present work, Al/Rare Earths （REE： Y, Ce, La, Pr and Nd） pillared clays （PILCs） were used to support 0.2 wt.% of palladium for the complete oxidation of low concentration of benzene. The supports and catalysts were characterized by XRD, N2 adsorp- tiorddesorption, FTIR spectroscopy, HRTEM and H2-TPR techniques. The results indicated that after Al and Al/REE pillaring, the basal spacing, SBET, Amic and Vmic of Al and AIREE-PILC had a considerable increase compared with those of Na-mmt. Activity tests of deep oxidation of benzene showed that the catalytic activity of Pd catalysts supported on Al and AIREE-PILC were much higher than that on initial clays, which was due to the fact that optimized structure of PILCs, such as large basal spacing, high SBET and porosity, improved Pd dispersion and increased the active sites of Pd. Especially for Pd/AICe-PILC, the temperature of complete oxidation was about 280 ℃, exhibiting the highest catalytic activity.

关键词： pillared clays porous materials benzene catalytic oxidation rare earths

Electrochemical and microstructural characterization of cyclic redox behaviour of SOFC anodes

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Rare Metals 2006年第Z1期25卷 300-304页

作者： KONG Jiangrong SUN Kening ZHOU Derui ZHANG Naiqing QIAO Jinshuo Department of applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China

The oxidation of Ni to NiO in solid oxide fuel cell (SOFC) anode will result in large bulk volume change, which may change the interfaces of the two phases in the anode cermet and thus may cause significant performance degradation. The reduction and oxidation (redox) of the Ni/YSZ cermet were studied at 800 ℃. Anodic polarization measurements were performed before and after redox cycles. The anode current density at an overpotential of 100 mV kept decreasing during the whole redox treatment. It decreased from 19.11 to 7.95 mA·cm-2 after two redox cycles. Anode supported unit cell was assembled for cell′s discharge measurements. Cell performance declined after each redox cycle. The maximum power density decreased from 126.28 to 40.32 mW·cm-2. The microstructural changes after redox cycling were recorded using scanning electron microscopy (SEM). The results reveal that after re-oxidation, the Ni gets coarse and has a higher porosity; the nickel network structure turns to be desultory.

关键词： solid oxide fuel cells anode redox Ni NiO

Composition and structure of coatings on Ti-6Al-4V alloy by micro-plasma oxidation in NaAlO2 solution

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 162-165页

作者： YAO Zhong-ping JIANG Zhao-hua SUN Xue-tong WU Zheng-dong ZHANG Xue-lin Department of applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China

Compound ceramic coatings on Ti-6Al-4V alloy were prepared for different time by pulsed bi-polar micro-plasma oxidation (MPO) in NaAlO2 solution. The phase composition was studied by XRD. And the electrochemical impedance spectra (EIS) of the coatings were measured to study the structure of the coatings, combined with the surface morphology. Using the proper EIS interpreting software, the "equivalent circuit" of the coatings was established, and meanwhile fitting values of equivalent element were obtained. The results show that the coating is composed of Al2 TiO5, α-Al2O3 and rutile TiO2, of which Al2 TiO5 is the main crystalline. Increasing the MPO time, the contents of Al2TiO5, rutile TiO2 and α-Al2O3 in the surface of the coating increase. And the EIS analysis and the surface morphology of the coatings illustrates the double-layer structure of the coatings, and the outer layer is loosen and the inner layer is compact. With the increase of the oxidizing time, the surface coarse degree of the coatings and the porosity of the outer layer of the coating are increased while the compactness of the inner layer of the coating is improved.

关键词： micro-plasma oxidation ceramic coatings electrochemical impedance spectra Ti-6Al-4V alloy

Preparation and Characterization of Nanocrystalline CeO_2 by Precipitation Method

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Journal of Rare Earths 2002年第6期20卷 583-586页

作者：董相廷李明张伟刘桂霞洪广言 Faculty of applied Sciences Changchun Institute of Optics and Fine Mechanics Changchun institute of applied Chemistry Chinese Academy of Sciences

CeO 2 nanocrystalline particulates with different sizes were prepared by precipitation method using ethanol as dispersive and protective reagent. XRD spectra show that the synthesized CeO 2 has cubic crystalline structure of space group O 5 H-F M3M, when calcination temperature is in the range of 250～800 ℃. TEM images reveal that CeO 2 particles are spherical in shape. The average size of the particles increases with the increase of calcination temperature. Thermogravimetric analysis indicates that the weight loss of precursor mainly depends on the calcination temperature, and little depends on the calcination time. Measurements of CeO 2 relative density show that the relative density of CeO 2 nanocrystalline powders increases with increasing CeO 2 particle size.

关键词： rare earths cerium oxide nanoparticulate precipitation method

Dirac R-matrix calculations of photoionization cross sections of Ni Ⅻ and atomic structure data of Ni 

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Chinese Physics B 2017年第2期26卷 127-140页

作者： R T Nazirt M A Bari M Bilal S Sardar M H Nasim M Salahuddin Department of Physics and applied Mathematics Pakistan Institute of Engineering and Applied Sciences Islamabad 45650 Pakista

We performed R-matrix calculations for photoionization cross sections of the two ground state configuration 3s^23p^5（~2P_（3/2,1/2）~o） levels and 12 excited states of Ni Ⅻ using relativistic Dirac Atomic R-matrix Codes（DARC） across the photon energy range between the ionizations thresholds of the corresponding states and well above the thresholds of the last level of the Ni XIII target ion. Generally, a good agreement is obtained between our results and the earlier theoretical photoionization cross sections. Moreover, we have used two independent fully relativistic GRASP and FAC codes to calculate fine-structure energy levels, wavelengths, oscillator strengths, transitions rates among the lowest 48 levels belonging to the configuration（3s^23p^4, 3s3p^5, 3p^6, 3s^23p^33d） in Ni XIII. Additionally, radiative lifetimes of all the excited states of Ni XIII are presented. Our results of the atomic structure of Ni XIII show good agreement with other theoretical and experimental results available in the literature. A good agreement is found between our calculated lifetimes and the experimental *** present results are useful for plasma diagnostic of fusion and astrophysical plasmas.

关键词： photoionization cross sections energy levels wavelengths lifetimes

Two-Dimensional Hybrid Model for High-Current Electron Beam Transport in a Dense Plasma

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Plasma Science and Technology 2014年第11期16卷 1007-1012页

作者：曹莉华王欢张华刘占军吴俊峰李百文 institute of applied Physics and Computational Mathematics HEDPS Center for Applied Physics and TechnologyPeking University

A two-dimensional hybrid code is developed to model the transport of a high-current electron beam in a dense plasma target. The beam electrons are treated as particles and described by particle-in-cell simulation including collisions with the target plasma particles. The background target plasma is assumed to be a stationary fluid with temperature variations. The return current and the self-generated electric and magnetic fields are obtained by combining Amp^re＇s law without the displacement current, the resistive Ohm＇s law and Faraday＇s law. The equations are solved in two-dimensional cylindrical geometry with rotational symmetry on a regular grid, with centered spatial differencing and first-order implicit time differencing. The algorithms implemented in the code are described, and a numerical experiment is performed for an electron beam with Maxwellian distribution ejected into a uniform deuterium-tritium plasma target.

关键词： electron beam transport hybrid simulation energy deposition

Effect of radiation on compressibility of hot dense sodium and iron plasma using improved screened hydrogenic model with𝑙splitting

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Chinese Physics B 2021年第3期30卷 225-236页

作者： Amjad Ali G Shabbir Naz Rukhsana Kouser Ghazala Tasneem M Saleem Shahzad Aman-ur-Rehman M H Nasim Department of Physics and applied Mathematics Pakistan Institute of Engineering and Applied SciencesIslamabad 45650Pakistan Department of Nuclear Engineering Pakistan Institute of Engineering and Applied SciencesIslamabad 45650Pakistan

High pressure investigations of matter involve the study of strong shock wave dynamics within the materials which gives rise to many thermal effects leading to dissociation of molecules,ionization of atoms,and radiation emission,*** response of materials experiencing a strong shock can be determined by its shock Hugoniot calculations which are frequently applied in numerical and experimental studies in inertial confinement fusion,laboratory astrophysical plasma,*** studies involve high energy density plasmas in which the radiation plays an important role in determining the energy deposition and maximum compressibility achieved by the shock within *** this study,we present an investigation for the effect of radiation pressure on the maximum compressibility of the material using shock Hugoniot *** shock Hugoniot calculations,an equation of state(EOS)is developed in which electronic contributions for EOS calculations are taken from an improved screened hydrogenic model with−l splitting(I-SHML)[High Energy Density Physics(2018)2648]under local thermodynamic equilibrium(LTE)*** thermal ionic part calculations are adopted from the state of the art Cowan model while the cold ionic contributions are adopted from the scaled binding energy *** Shock Hugoniot calculations are carried out for sodium and iron plasmas and our calculated results show excellent agreement with published results obtained by using either sophisticated self-consistent models or the first principle study.

关键词： self-consistent-field methods thermodynamics of plasmas average atom model shock Hugoniot calculation

Experimental investigation of the relativistic backward wave oscillator with a periodic guiding magnetic field

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Chinese Physics C 2010年第4期34卷 499-501页

作者：马乔生刘忠吴勇金晓 institute of applied Electronics CAEP

Experiment is carried out on the accelerator Sinus-700 to investigate the Relativistic Backward Wave Oscillator （RBWO） with a periodic guiding magnetic field. When the strength of the guiding magnetic field, whose period is 4.6 cm, is 0.54 T, a microwave output power of 0.95 GW at 9.1 GHz microwave frequency is achieved. It is shown that the RBWO with a periodic guiding magnetic field is feasible.

关键词： high power microwave (HPM) RBWO periodic guiding magnetic field accelerator

Design and test of SX-FEL cavity BPM

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Chinese Physics C 2013年第11期37卷 100-103页

作者：袁任贤周伟民陈之初俞路阳王宝鹏冷用斌 Shanghai institute of applied Physics

This paper reports the design and cold test of the cavity beam position monitor （CBPM） for SX-FEL to fulfill tile requirement of beam position measurement resolution of less than 1 p_m, even 0.1 btm. The CBPM was optimized by using a coupling slot to damp the TM010 mode in the output signal. Tile isolation of TM01o mode is about 117 dB, and the shunt impedance is about 200 ~@4.65 GHz with the quality factor 80 from MAFIA simulation and test result. A special antenna was designed to load power for reducing excitation of other modes in the cavity. The resulting output power of TM110 mode was about 90 mV/mm when the source was 6 dBm, and the accomplishable minimum voltage was about 200 btV. The resolution of the CBPM was about 0.1 btm from the linear fitting result based on the cold test.

关键词： cavity BPM resolution cold test antenna