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Rare Metals 2018年第11期37卷 983-988页

作者： Mu-Nan Yang Hang Wang Yong-Feng Hu Liu-Yi-Mei Yang Aimee Maclennan Bin Yang Institute of Engineering Research Jiangxi University of Scienceand Technology canadian light source University of Saskatchewan

Relationship between atomic local structures and Curie temperature of NdFeB permanent magnets was investigated semi-quantitatively using synchrotron radiation technique. Fe K-edge X-ray absorption spectroscopy(XAS) was employed to study the local structure of Fe atoms for samples before and after doping Dy, Tb or Gd. It is found that the bond lengths and coordination numbers are changed. Thus, the exchange interaction between Fe atoms inc.eases with Dy, Tb or Gd doping, resulting in the improvement of Curie temperature of NdFeB permanent magnets. The doping effect is proven by experimental measurement of the magnetic properties. Microstructural characterization using scanning electron microscopy(SEM) was also used to further analyze the effect of different rare earth elements doping on Curie temperature of NdFeB permanent magnets.

关键词： Permanent magnet Synchrotron radiation X-ray absorption fine structure Crystal structure Curie temperature

Comparative evaluation for catalytic gasification of petroleum coke and asphaltene in subcritical and supercritical water

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Journal of Energy Chemistry 2019年第4期28卷 107-118页

作者： Rachita Rana Sonil Nanda Aimee Maclennan Yongfeng Hu Janusz A.Kozinski Ajay K.Dalai Department of Chemical and Biological Engineering University of Saskatchewan Department of Chemical and Biochemical Engineering University of Western Ontario Soft X-Ray Micro-Characterization Beamline Canadian Light Source Inc. New Model in Technology & Engineering

Subcritical and supercritical water gasification of petroleum coke and asphaltene was performed at variable temperatures(350–650°C),feed concentrations(15–30 wt%)and reaction times(15–60 min).Nickel-impregnated activated carbon(Ni/AC)was synthesized as a catalyst for enhancing syngas yields at optimal gasification conditions(650°C,15 wt%and 60 min).Structural chemistry of precursors and chars developed at different gasification temperatures was studied using physicochemical and synchrotronbased approaches such as carbon–hydrogen–nitrogen–sulfur(CHNS)analysis,thermogravimetric and differential thermogravimetric analysis(TGA/DTA),scanning electron microscopy(SEM),Fourier-Transform Infrared spectroscopy(FTIR),Raman spectroscopy,X-ray diffraction(XRD)and X-ray absorption spectroscopy(XAS).Asphaltene testified to be a better precursor for catalytic hydrothermal gasification leading to 11.97 mmol/g of total gas yield compared to petroleum coke(8.04 mmol/g).In particular,supercritical water gasification using 5 wt%Ni/AC at 650°C with 15 wt%feed concentration for 60 min resulted in 4.17 and 2.98 mmol/g of H_2from asphaltene and petroleum coke,*** the same conditions,the respective CH_4yields from catalytic gasification of asphaltene and petroleum coke were 2.54and 1.07 mmol/***,asphaltene also seemed to an attractive feedstock for the production of highly aromatic chars through hydrothermal gasification.

关键词： Asphaltene Petroleum coke Subcritical water Supercritical water Gasification Char

Room temperature oxidation of acetone by ozone over alumina-supported manganese and cobalt mixed oxides

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Frontiers of Chemical Science and Engineering 2020年第6期14卷 937-947页

作者： Mehraneh Ghavami Mostafa Aghbolaghy Jafar Soltan Ning Chen Department of Chemical and Biological Engineering University of SaskatchewanSaskatoonS7N 5 A9Canada canadian light source inc. University of SaskatchewanSaskatoonS7N 0X4Canada

Volatile organic compounds(VOCs)are among the major sources of air *** ozonation is an efficient process for removing VOCs at lower reaction temperature compared to catalytic *** this study,a series of alumina supported single and mixed manganese and cobalt oxides catalysts were used for ozonation of acetone at room *** influence of augmenting the single Mn and Co catalysts were investigated on the performance and structure of the *** manganese and cobalt single and mixed oxides catalysts of the formula Mnl0%-CoX and Co10%-MnX(where X=0,2.5%,5%,or 10%)were *** was found that addition of Mn and Co at lower loading levels(2.5%or 5%)to single metal oxide catalysts enhanced the catalytic *** mixed oxides catalysts of(Mnl0%-Co2.5%)and(Mn10%-Co5%)led to acetone conversion of about 84%.It is concluded that lower oxidation state of the secondary metal improves ozone decomposition and oxidation of acetone.

关键词： ozone VOC manganese oxides cobalt oxides alumina support

A novel water layer structure inside nanobubbles at room temperature

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Nuclear Science and Techniques 2014年第6期25卷 81-83页

作者：张立娟王建罗毅方海平胡钧 Shanghai Institute of Applied Physics Chinese Academy of Sciences canadian light source inc. University of Saskatchewan Hefei National Laboratory for Physical Sciences at Microscale University of Science and Technology of China Department of Theoretical Chemistry and Biology Royal Institute of Technology

Molecularly thin water layer, with a hydrogen bonding network different from those in bulk water and ice, has unique properties and is generally involved in many important processes such as wetting, erosion, atmosphere chemical reaction, protein folding and biomolecular interaction. Here, we report a new water layer structure at room temperature, which is found inside nanobubbles by using synchrotron based scanning transmission soft X-ray microscopy(STXM). The three peaks 535.0, 536.8 and 540.9 e V at O K edge inside the nanobubbles show a novel characteristics of very thin water layers, which has never been observed before.

关键词：纳米气泡层结构水层室温软X射线显微镜大气化学反应生物分子蛋白质折叠

Effective transport network driven by tortuosity gradient enables high-electrochem-active solid-state batteries

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National Science Review 2023年第3期10卷 178-188页

作者： Qing-Song Liu Han-Wen An Xu-Feng Wang Fan-Peng Kong Ye-Cai Sun Yu-Xin Gong Shuai-Feng Lou Yi-Fan Shi Nan Sun Biao Deng Jian Wang Jia-Jun Wang Ministry of Industry and Information Technology(MIIT) Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of Technology(HIT) Chongqing Research Institute of HIT Shanghai Institute of Applied Physics Chinese Academy of Sciences canadian light source inc. University of Saskatchewan

Simultaneously achieving high electro chemical activity and high loading for solid-state batteries has been hindered by slow ion transport within solid electrodes,in particular with an inc.ease in electrode *** transport governed by ’point-to-point’ diffusion inside a solid-state electrode is challenging,but still remains ***,synchronized electrochemical analysis using X-ray tomography and ptychography reve als new insights into the nature of slow ion transport in solid-state electrodes.’hickness-dependent delithiation kinetics are spatially probed to identify that low-delithiation kinetics originate from the high tortuous and slow longitudinal transport *** fabricating a tortuosity-gradient electrode to create an effective ion-percolation network,the tortuosity-gradient electrode architecture promotes fast charge transport,migrates the heterogeneous solid-state reaction,enhances electrochemical activity and extends cycle life in thick solid-state ele *** findings establish effective transport pathways as key design princ.ples for realizing the promise of solid-state high-loading cathodes.

关键词： all-solid-state batteries thick electrodes lithiation/delithiation heterogeneity tortuosity gradient synchrotron techniques

Determination of the calcium species in coal chars by Ca K-edge XANES analysis

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Chinese Physics C 2013年第2期37卷 102-104页

作者：刘利娟刘慧君崔明启胡永峰郑雷赵屹东马陈燕席识博杨栋亮郭志英王杰 Institute of High Energy Physics Chinese Academy of Sciences Department of Chemical Engineering for Energy East China University of Science and Technology canadian light source University of Saskatchewan

Ca-based additives have been widely used as a sulfur adsorbent during coal pyrolysis and gasification. The Ca speciation and evolution during the pyrolysis of coal with Ca additives have attracted great attention. In this paper, Ca species in the coal chars prepared from the pyrolysis of Ca（OH）2 or CaCO3-added coals are studied by using Ca K-edge X-ray absorption near-edge structural spectroscopy. The results demonstrate that Ca（OH）2 , CaSO4 , CaS and CaO coexist in the Ca（OH）2-added chars, while Ca（OH）2 and CaSO4 are the main species in the Ca（OH）2-added chars. Besides, a carboxyl-bound Ca is also formed during both the pyrolysis for the Ca（OH）2-added and the CaCO3-added coals. A detailed discussion about the Ca speciation is given.

关键词： char pyrolysis calcium K-edge XANES

Rational synthesis of CaCo_2O_4 nanoplate as an earth-abundant electrocatalyst for oxygen evolution reaction

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Journal of Energy Chemistry 2019年第4期28卷 125-131页

作者： Xiao Lin Jing Zhou Dehua Zheng Chengzhi Guan Guoping Xiao Ning Chen Qing Liu Hongliang Bao Jian-Qiang Wang Shanghai Institute of Applied Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory of Eco-chemical Engineering College of Chemistry and Molecular Engineering Qingdao University of Science and Technology canadian light source University of Saskatchewan

To accelerate the kinetics of oxygen evolution reaction(OER)regarding the energy conversion and storage approaches,the discovery of desirable cost-effective and highly efficient electrocatalysts is of prime *** study demonstrates a layered CaCo_2O_4with a two-dimensional nanoplate structure,which possesses electrocatalytic activity for *** OER activity was achieved on CaCo_2O_4with a Tafel slope of 71 mV dec^(-1)and a current density of 10 mA cm^(-2)at an overpotential of 371 mV,which was more active than the similar structure LiCoO_*** with X-ray absorption fine structure and density functional theory calculations,the enhanced OER activity and stability are mainly attributed to the unique electronic structure derived from the interaction of Ca and Co,and improved electrical ***_2O_4can be developed as a highly active and earth-abundant catalyst for OER in energy conversion and storage technologies.

关键词： Oxygen evolution reaction CaCo2O4 2D nanoplates Electrocatalysts

Mechanism of soft x-ray continuum radiation from low-energy pinc. discharges of hydrogen and ultra-low field ignition of solid fuels

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Plasma Science and Technology 2017年第9期19卷 7-34页

作者： R MILLS J LOTOSKI Y LU Brilliant light Power Inc.493 Old Trenton RoadCranburyNJ 08512United States of America

EUV continuum radiation（10–30 nm） arising only from very low energy pulsed pinc. gas discharges comprising some hydrogen was first observed at Black light Power, inc. and reproduced at the Harvard Center for Astrophysics（Cf A）. The source was determined to be due to the transition of H to the lower-energy hydrogen or hydrino state H（1/4） whose emission matches that observed wherein alternative sources were eliminated. The identity of the catalyst that accepts 3 · 27.2 eV from the H to cause the H to H（1/4） transition was determined to HOH versus 3H. The mechanism was elucidated using different oxide-coated electrodes that were selective in forming HOH versus plasma forming metal atoms as well as from the intensity profile that was a mismatch for the multi-body reaction required during 3H catalysis. The HOH catalyst was further shown to give EUV radiation of the same nature by igniting a solid fuel comprising a source of H and HOH catalyst by passing a low voltage, high current through the fuel to produce explosive plasma. No chemical reaction can release such high-energy light. No high field existed to form highly ionized ions that could give radiation in this EUV region that persisted even without power input. This plasma source serves as strong evidence for the existence of the transition of H to hydrino H（1/4） by HOH as the catalyst and a corresponding new power source wherein initial extraordinarily brilliant light-emitting prototypes are already producing photovoltaic generated electrical power. The hydrino product of a catalyst reaction of atomic hydrogen was analyzed by multiple spectroscopic techniques. Moreover, the m H catalyst was identified to be active in astronomical sources such as the Sun, stars and interstellar medium wherein the characteristics of hydrino match those of the dark matter of the Universe.

关键词： ignition continuum brilliant catalysis matches elucidated reproduced spectroscopic figure helium

Molten salt-assisted synthesis of bulk CoOOH as a water oxidation catalyst

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Journal of Energy Chemistry 2020年第3期29卷 5-10页

作者： Sanzhao Song Hongliang Bao Xiao Lin Xian-Long Du Jing Zhou Linjuan Zhang Ning Chen Jun Hu Jian-Qiang Wang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China canadian light source University of SaskatchewanSaskatoon S7N 2V3Canada

Different sizes of layered CoOOH were synthesized by the molten-salt-assisted method at different temperatures.X-ray diffraction and scanning electron microscope studies reveal that CoOOH grew at(003)with inc.easing temperature,and its size can reach dozens of microns.X-ray absorption near edge structure and XPS studies demonstrate that the Co valence state of CoOOH-750 is trivalent,and X-ray Absorption Fine Structure shows that it had a higher symmetry and lower disorder degree,indicating that CoOOH-750 has higher crystallinity and Co3+.The results of electrochemical tests show that CoOOH-750 exhibited the best oxygen-evolution-reaction(OER)catalytic activity.

关键词： Molten-salt-assisted synthesis CoOOH Crystallinity Water oxidation catalyst

Growth performance,gastrointestinal weight,microbial metabolites and apparent retention of components in broiler chickens fed up to 11%rice bran in a corn-soybean meal diet without or with a multi-enzyme supplement

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Animal Nutrition 2019年第1期5卷 41-48页

作者： Juan Sanchez Aizwarya Thanabalan Tanka Khanal Rob Patterson Bogdan A.Slominski Elijah Kiarie Department of Animal Biosciences University of Guelph canadian Bio-Systems inc. Department of Animal Science University of Manitoba

We investigated the effects of adding up to 11% rice bran(RB) in corn-soybean meal diets fed to broiler chickens without or with a multi-enzyme supplement(MES). The MES supplied xylanase, b-glucanase invertase, protease, cellulase, a-amylase and mannanase with targeted activity of 2,500, 300, 700, 10,0001,200, 24,000, and 20 U/kg of feed, respectively. The study used a two-phase feeding program(starter d 0 to 24; finisher, d 25 to 35) with RB added at 5% and 11%, respectively creating 4 diets in each phase Diets were iso-caloric and iso-nitrogenous and contained phytase(500 FTU/kg) and TiO_2 as a digestibility marker. Three hundred and sixty d-old male Ross 708 broiler chicks were placed in cages based on BW(15 birds/cage) and allocated to 4 diets(n = 6). Birds had free access to feed and water. Body weight and feed intake were recorded. Excreta samples were collected 3 d prior to the end of each phase for apparent retention(AR) of components. Samples of birds were sacrificed on d 24 and 35 for gut weight and ceca digesta for organic acid content. There was no interaction(P > 0.10) between RB and MES on BWG and FCR in starter or finisher phase. In finisher phase, birds fed MES had better BWG(961 versus 858 g) and FCR(1.69 versus 1.86) than birds fed non-MES diets(P inc.eased gizzard weight and reduced final BW whereas MES improved growth and energy utilization.

关键词： Broiler chickens Growth performance Gut weight Microbial activity Multi-enzyme supplement Rice bran