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Properties and evaluation of amidoxime-based UHMWPE fibrous adsorbent for extraction of uranium from seawater

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science China Chemistry 2013年第11期56卷 1504-1509页

作者： XING Zhe HU JiangTao WANG MouHua ZHANG WenLi LI ShiNeng GAO QianHong WU GuoZhong Shanghai institute of applied physics Chinese Academy of Sciences

An amidoxime-based ultra-high molecular weight polyethylene （UHMWPE） fibrous adsorbent was successfully prepared by T-irradiation-induced graft copolymerization of acrylonitrile （AN） and acrylic acid （AA）, followed by amidoximation. The grafting of AN and AA on the UHMWPE fiber and the amidoximation of the grafted fiber were confirmed by Fourier transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis. The mechanical property of the original and modified UHMWPE fibers was compared by single-filament strength test. The adsorption property of the UHMWPE fibrous adsorbent was evaluated by adsorption test in uranyl nitrate solution and seawater. The surface of the modified UHMWPE fibers was covered by the grafting layer and became rough. The tensile strength of the amidoxime-based UHMWPE fibrous adsorbent was influenced by the absorbed dose and hydrochloric acid elution, but was independent of the grafting yield and amidoximation. The uranium adsorption amount of the amidoxime-based UHMWPE fibrous adsorbent after immersing in seawater for 42 days was 2.3 mg-U/g.

关键词： ultra-high molecular weight polyethylene fiber acrylonitrile acrylic acid radiation graft copolymerization amidoxi-mation uranium extraction

Black Carbon Particles in the Urban Atmosphere in Beijing

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Advances in Atmospheric sciences 2005年第5期22卷 640-646页

作者：王庚辰白建辉孔琴心 Alexander EMILENKO institute of Atmospheric physics Chinese Academy of Sciences institute of Atmospheric physics Russian Academy of Sciences Moscow 109017

A study of the concentration of black carbon particles and its variation in the urban atmosphere has been carried out since 1996 in the Beijing area. The measurements were done in the late autumn and early winter each year, the period before and after domestic heating activities begin. The results show the presence of black carbon particles at the high level that vary over a large range in the urban atmosphere in Beijing. The mean value of daily average concentration for the whole observation period of 1996-2004 is 20.0 μgm^-3. An evident decrease of black carbon particle concentration in the Beijing area is observed after 2000, and the daily average concentration of black carbon particles is estimated to be 16.0 μgm^-3 with a variation range of 2.10-50.50 μgm^-3 for the period of 2000-2004. The observation method and main variation behavior characteristics of black carbon particles in the urban atmosphere in the Beijing area are given and discussed.

关键词： black carbon particles urban atmosphere aerosols Beijing

Applications of in-situ solid-state nuclear magnetic resonance in methanol to olefins reaction

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science China Chemistry 2025年第01期 134-151页

作者： Jing Niu Shutao Xu Yingxu Wei Zhongmin Liu National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of Sciences State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese academy of sciences

The methanol-to-olefins（MTO） reaction offers an alternative pathway for the production of low-carbon olefins from non-oil feedstocks. Fundamental research has been impeded by a lack of comprehensive understanding of its underlying mechanism,despite the significant progress made in industry. In-situ solid-state nuclear magnetic resonance（ss NMR） spectroscopy has emerged as a pivotal tool, offering crucial insights into key species under real-time operando conditions. Furthermore, the host–guest interaction between zeolites or surface species residing on zeolites and the reactant/active intermediates is revealed by the combination of in-situ13C MAS NMR and 2D correlation spectroscopy. Moreover, recent technological advancements in hyperpolarization（HP） methods, including HP129Xe NMR and dynamic nuclear polarization（DNP）, have significantly improved the sensitivity of ss NMR, enabling detailed structural and kinetic analysis as well as the detection of trace species. In this feature article, we summarized recent advancements in（in-situ） ss NMR spectroscopy applied to MTO reaction processes,encompassing mechanistic investigations at various stages and the intricate host–guest interactions. These theoretical insights into the dynamic evolution of MTO reactions lay a solid foundation for the optimization of catalytic processes and the development of efficient catalysts, thereby advancing the techniques towards more sustainable and economical production route for olefins.

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Hollow bismuth ferrite combined graphene as advanced anode material for sodium-ion batteries

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Progress in Natural science:Materials International 2020年第2期30卷 153-159页

作者： Xuli Ding Yi Liu Department of physics School of ScienceJiangsu University of Science and Technology Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied PhysicsChinese Academy of Science

Hollow bismuth ferrite nanofibers were fabricated via simple electrospinning process,and the storage properties of Na-ions were investigated by atmospheric pressure X-ray photoelectron spectrum（APXPS） and Synchrotron *** results show that the hollow bismuth ferrite nanotubes demonstrate impressive sodium storage properties and good cycling stability that the specific capacity can exceed 500 mA h g;and the cycle number reaches several hundred *** graphene-coated bismuth ferrite nanotubes exhibit a specific capacity of600 mAhg;and a 89% capacity retention after 200 *** present strategy can be a significant step to fabricate hollow perovskite oxides and serve as sodium ion batteries.

关键词： Bismuth ferrite Perovskite Hollow Sodium-ion battery Anode

Chen’s lattice inversion embedded-atom method for Ni-Al alloy

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Chinese physics B 2012年第11期21卷 172-178页

作者：张川晖黄烁申江陈难先 University of science and Technology Beijing Institute of Applied Physics

The structural properties, the enthalpies of formation, and the mechanical properties of some Ni-Al intermetallic compounds （NiAl, Ni3Al, NiAl3, Ni5Al3, Ni3Al4） are studied by using Chen＇s lattice inversion embedded-atom method （CLI-EAM）. Our calculated lattice parameters and cohesive energies of Ni-A1 compounds are consistent with the experimental and the other EAM results. The results of enthalpy of formation indicate a strong chemical interaction between Ni and Al in the intermetallic compounds. Through analyzing the alloy elastic constants, we find that all the Ni-Al intermetallic compounds discussed are mechanically stable. The bulk moduli of the compounds increase with the increasing Ni concentration. Our results also suggest that NiAl, Ni3Al, NiAl3, and Ni5Al3 are ductile materials with lower ratios of shear modulus to bulk modulus; while Ni3Al4 is brittle with a higher ratio.

关键词： embedded-atom method lattice inversion NiAl alloy mechanical property

DIFFUSING OF AN AMMONIA MOLECULE IN WATER IN A VERY SHORT TIME PERIOD

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Journal of Hydrodynamics 2012年第6期24卷 969-970页

作者： SHENG Nan TU Yu-song GUO Pan WAN Rong-zheng FANG Hai-ping Shanghai institute of applied physics Chinese Academy of Science University of the Chinese academy of sciences institute of Systems Biology Shanghai University

The diffusion of an ammonia molecule （NH3） in water was investigated by molecular dynamic simulations. It is found that the diffusion shows negative correlation with its dipole orientation.

关键词： diffusion ammonia correlation

First-principles calculation of electronic structure of Mg_xZn_(1-x)O codoped with aluminium and nitrogen

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Chinese physics B 2011年第1期20卷 528-533页

作者：张明张川晖申江 institute of applied physics University of Science and Technology Beijing

Aiming at developing p-type semiconductors and modulating the band gap for photoelectronic devices and band engineering, we present the ab initio numerical simulation of the effect of codoping ZnO with Al, N and Mg on the crystal lattice and electronic structure. The simulations are based on the Perdew-Burke-Ernzerhof generalised-gradient approximation in density functional theory. Results indicate that electrons close to the Fermi level transfer effectively when Al, Mg, and N replace Zn and O atoms, and the theoretical results were consistent with the experiments. The addition of Mg leads to the variation of crystal lattice, expanse of energy band, and change of band gap. These unusual properties are explained in terms of the computed electronic structure, and the results show promise for the development of next-generation photoconducting devices in optoelectronic information science and technology.

关键词： first-principles electronic structure ZnO doping

Density-functional study of CO adsorbed on Rh_N (N=2-19) clusters

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Chinese physics B 2011年第12期20卷 192-199页

作者：田付阳申江 institute for applied physics University of Science and Technology Beijing

We investigate the structural, electronic and adsorption properties of one single CO molecule adsorbed on RhN （N = 2-19） clusters, using the density-functional theory in the spin-polarized generalized gradient approximation. It is found that the structural growth model of the RhN clusters transforms from double layers （N = 12-16） to three layers （N ： 17-19）. Three different adsorption types are the atop site adsorption for N = 6, 8, 9, 11, 12, the bridge site adsorption for N ： 2-5, 7, 10, 13-15, 17 and the face adsorption for N = 16, 18, 19. The adsorption abilities of RhN clusters are related to C-O bond length, vibrational frequency, adsorption energy and the charge transfer between CO and Rh clusters as well as the electronic density of state. With the increase of Rh cluster size, the adsorption energy of CO adsorbed on RhN clusters tends to be 2.2 eV-2.3 eV, which is 0.2 eV-0.3 eV larger than the theoretical value （about 2.0 eV） of CO molecule adsorption on clean Rh （111） surface.

关键词： CO-RhN compounds adsorption energy vibrational frequency electronic density ofstate

Determination of the stellar reaction rate for ^(12)C(α, γ)^(16)O: using a new expression with the reaction mechanism

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Chinese physics B 2009年第4期18卷 1421-1427页

作者：徐毅徐望马余刚蔡翔舟陈金根范功涛樊广伟郭威罗文潘强岩沈文庆杨利峰 Shanghai institute of applied physics Chinese Academy of Sciences Graduate School of the Chinese academy of sciences

The astrophysical reaction rate of 12C（α,γ）16O plays a key role in massive star evolution. However, this reaction rate and its uncertainties have not been well determined yet, especially at T9=0.2. The existing results even disagree with each other to a certain extent. In this paper, the El, E2 and total （E1＋E2） 12C（α,γ）16O reaction rates are calculated in the temperature range from T9=0.3 to 2 according to all the available cross section data. A new analytic expression of the 12C（α,γ）16O reaction rate is brought forward based on the reaction mechanism. In this expression, each part embodies the underlying physics of the reaction. Unlike previous works, some physical parameters are chosen from experimental results directly, instead of all the parameters obtained from fitting. These parameters in the new expression, with their 3σ fit errors, are obtained from fit to our calculated reaction rate from T9=0.3 to 2. Using the fit results, the analytic expression of 12C（α,γ）16Oreaction rate is extrapolated down to T9=0.05 based on the underlying physics. The 12C（α,γ）16O reaction rate at T9=0.2 is （8.78 ± 1.52） × 10^15 cm3s^-1mol^-1. Some comparisons and discussions about our new 12C（α,γ）16Oreaction rate are presented, and the contributions of the reaction rate correspond to the different part of reaction mechanism are given. The agreements of the reaction rate below T9=2 between our results and previous works indicate that our results are reliable, and they could be included in the astrophysical reaction rate network. Furthermore, we believe our method to investigate the 12C（α,γ）16O reaction rate is reasonable, and this method can also be employed to study the reaction rate of other astrophysical reactions. Finally, a new constraint of the supernovae production factor of some isotopes are illustrated according to our 12C（α,γ）16O reaction rates.

关键词： nucleosynthesis thermonuclear reaction rate stellar evolution supernovae