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Joined AZ31B Magnesium Alloys with Ag Interlayer by Ultrasonic-Induced Transient Liquid Phase Bonding in Air

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1177-1185页

作者： qian Wang peng Yu Haoran Lin Chongzhi Guo Xiaoqiang Hu Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341119China School of Rare Earths University of Science and Technology of ChinaHefei230026China Shenyang 7D New Materials Equipment Co.LTD. Shenyang110076China Shenyang National Laboratory of Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

AZ31B magnesium alloys are commonly used in lightweight structures of automobile and aerospace *** this work,the ultrasonic-induced transient liquid phase bonding technique is deployed to joint AZ31B magnesium alloys at 490℃ with Ag interlayer in the *** effect of ultrasonic vibration on microstructure and mechanical properties of welding seam is *** vibration duration increases,the width of the welding seam increases firstly and then *** the ultrasound vibration sustained for one second,the eutectic reaction occurred in the contacting interface between Ag interlayer and the base metal AZ31B,resulting in formation of liquid phase and metallurgical *** the ultrasound vibration sustained for seven second,the width of the welding seam increased to a maximum of about 303.1μm and the average shear bond strength of the welding joint attained the peak value of about 66.87 *** the ultrasound vibration sustained over seven seconds,the liquid phase is gradually squeezed out and the width of the welding seam decreases.α-Mg and AgMg_(3) can be observed in the welding *** analysis shows thatα-Mg has a certain strengthening *** whole process of appearance,growth and integration ofα-Mg is analyzed.

关键词： Ultrasonic bonding Magnesium alloy Silver Microstructure Intermetallic compound

High retention volume covalent organic polymer for xenon capture:Dynamic separation of Xe and Kr

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Green Energy & Environment 2022年第5期7卷 948-956页

作者： qian Wang Zhu Meng Juntao Li Shuming peng Zhonghua Xiang Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyangSichuan621900China State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing100029China Department of Chemistry Imperial College London20 Gordon StreetLondonWC1H0AJUK Department of Chemistry University College LondonLondonW120BZUK

Xenon capture and Xe/Kr separation are important processes in *** instance,Xe/Kr separation is an indispensable step in recycle and treatment of nuclear fuel *** different separation methods,selectively adsorb gas molecules using porous materials is a promising way to reduce the high energy consumption in traditional cryogenic ***,many reported adsorbents still face the challenges of:ⅰ) poor separation property at low Xe/Kr concentrations;ⅱ) insufficient retention volumes,which influence the viability of whole *** this work,we present a stable covalent organic polymer,i.e.,COP-14,showing promising potential for Xe/Kr *** dynamic breakthrough experiments,COP-14 successfully separates low concentration Xe(350 ppm) and Kr(35 ppm) from target gas ***,the xenon retention volume per gram(1700 mL g^(-1) at 298 K) of COP-14 in dynamics absorption process achieves 3.8 times of benchmark active *** good performance of the newly devloped COP-14 mainly from its rich nitrogen sites and suitable pore size with xenon *** promising results of COP-14 on Xe/Kr separation in this work provide a promising way for designing efficient Xe/Kr separation mateirals.

关键词： process separation retention

Phase engineering activation of low-cost iron-containing sulfide minerals for advanced electrocatalysis

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Journal of Materials Science & Technology 2022年第16期111卷 181-188页

作者： Jun Mei qian Zhang Hong peng Ting Liao Ziqi Sun Centre for Materials Science Queensland University of Technology2 George StreetBrisbaneQLD 4000Australia School of Chemistry and Physics Queensland University of Technology2 George StreetBrisbaneQLD 4000Australia College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China School of Chemical Engineering The University of QueenslandBrisbaneQLD 4072Australia School of Mechanical Medical and Process Engineering Queensland University of Technology2 George StreetBrisbaneQLD 4000Australia

Sustainable energy conversion and storage provide feasible approaches towards green energy solutions and carbon *** high cost and complex fabrication process of advanced energy nanomaterials,however,has impeded the practical application of emerging sustainable *** direct use of earth-abundant natural minerals which contain active elements for effective catalysis and energy storage should be a promising approach to achieve affordable sustainable energy supply and green fuel ***,as typical examples of activating natural minerals for electrocatalysis,two common minerals,pyrite and chalcopyrite,are activated via a one-step phase transformation *** a facile thermal reduction process,the minerals are completely transformed into active pyrrhotite(FeS)and haycockite(Cu_(4)Fe_(5)S_(8))*** thermal reduction resulting phase transformation can lead to significant surface disordering and can contribute to the catalytic activity by offering favourable electronic structure for intermediates adsorption,abundant surficial active centres,and substantial surface redox *** activated minerals are examined for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)*** obtained haycockite phase delivers the best performance towards acidic HER and alkaline *** phase optimization is performed via loading a low percentage of iridium nanoclusters on the haycockite phase deposited onto a carbon cloth substrate,through which an overpotential as low as 310 mV for achieving 10 mA cmand a small Tafel slope of 55.6 m V dec-1are recorded for alkaline *** work demonstrates the feasibility of the direct use of cost-effective natural resources for addressing the current energy-related issues and paves a way to reach affordable practical emerging sustainable technologies.

关键词： Minerals Phase transformation Sulfides Oxygen evolution Electrocatalysis

Partner selection strategies in cooperative wireless networks with optimal power distribution

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The Journal of China Universities of Posts and Telecommunications 2008年第3期15卷 47-50,58页

作者： ZHANG qian-qian GAO Wei-dong peng Mu-gen WANG Wen-bo Wireless Signal Processing and Network Laboratory Beijing University of Posts and Telecommunications Beijing 100876 China

There have been several results that illustrate the best performance that a network can get through cooperation of relay nodes. For practical purposes, not all nodes in the network should be involved at the same time in every transmission. Therefore, optimal partner selection protocols in cooperative wireless networks are believed to be the first important thing that should be paid attention to. This problem in our article is considered in the context of regenerative nodes and non-altruistic cooperation （no pure relay exists; all nodes have their own data to transmit）. For each transmission, the protocol must provide the user （source node） a ＇best partner＇（relay node） to cooperate with （for network simplicity and less transmission signals here, assume that each user has only one cooperative node）. A criterion is essentially needed when defining what a ＇best partner＇ is; in this article, two factors, i.e, the successful transmission probability and the transmission power, are considered. Three optimal partner selection strategies with different goals are proposed and analyzed respectively. The simulation results show that these are all supposed to be good tradeoffs between power consumption and transmission performance.

关键词： cooperative outage probability power distribution partner selection

Etching‑Induced Surface Reconstruction of NiMoO_(4) for Oxygen Evolution Reaction

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Nano-Micro Letters 2023年第2期15卷 271-282页

作者： Jinli Zhu Jinmei qian Xuebing peng Baori Xia Daqiang Gao Key Laboratory for Magnetism and Magnetic Materials of MOE Key Laboratory of Special Function Materials and Structure Design of MOELanzhou UniversityLanzhou 730000People’s Republic of China

Rational reconstruction of oxygen evolution reaction(OER)precatalysts and performance index of OER catalysts are crucial but still challenging for universal water ***,we develop a double-cation etching strategy to tailor the electronic structure of NiMoO_(4),where the prepared NiMoO_(4) nanorods etched by H_(2)O_(2) reconstruct their surface with abundant cation deficiencies and lattice *** results reveal that the double cation deficiencies can make the upshift of d-band center for Ni atoms and the active sites with better oxygen adsorption *** a result,the optimized sample(NMO-30M)possesses an overpotential of 260 mV at 10 mA cm−2 and excellent long-term durability of 162 ***,in situ Raman test reveals the rapid formation of high-oxidation-state transition metal hydroxide species,which can further help to improve the catalytic activity of NiMoO_(4) in *** work highlights the influence of surface remodification and shed some light on activating catalysts.

关键词： Etching Surface reconstruction Cation deficiencies OER

The Paley-Wiener theorem in the non-commutative and non-associative octonions

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Science China Mathematics 2009年第1期52卷 129-141页

作者： LI XingMin peng LiZhong qian Tao School of Computer South China Normal UniversityGuangzhou 510631China LMAM School of ComputerPeking UniversityBeijing 100871China Faculty of Science and Technology the University of Macao3001Macao

The Paley-Wiener theorem in the non-commutative and non-associative octonion analytic function space is proved.

关键词： octonionic exponential function octonionic Taylor expansion Fourier transform Paley-Weiner theorem 42B35 30G35 17A35

An Efficient Solid State Method for Deoximation under Mild Conditions

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Chinese Chemical Letters 2006年第12期17卷 1559-1562页

作者： Wang ZHOU qian He LI Sha peng Institute of Fine Catalysis and Synthesis Hunan Normal University Changsha 410080

Oximes of ketones and aldehydes are efficiently converted to the corresponding carbonyl compounds, using a combination of NaHSO4.H20 and paraformaldehyde in good to excellent yields under solid state conditions at roo... 详细信息

关键词： Solid state deoximation oxime carbonyl compound.

Restudy on Dark Matter Time-Evolution in the Littlest Higgs Model with T-Parity

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Communications in Theoretical Physics 2008年第11期50卷 1211-1218页

作者： QIAO Qing-peng TANG Jian LI Xue-qian Department of Physics Nankai University Tianjin 300071 China

Following previous study, in the littlest Higgs model （LHM）, the heavy photon is supposed to be a possiL dark matter candidate and its relic abundance of the heavy photon is estimated in terms of the Boltzman- Lee-Weinba time-evolution equation. The effect of the T-parity violation is also considered. Our calculations show that when Higmass MH taken to be 300 GeV and do not considering T-parity violation, only two narrow ranges 133 〈 MAH 〈 135 Ge and 167 〈 MAH〈 169 GeV are tolerable with the current astrophysical observation and if 135 〈 MAH 〈 167 GeV there must at least exist another species of heavy particle contributing to the cold dark matter. As long as the T-pari; can be violated, the heavy photon can decay into regular standard model particles and would affect the dark matt abundance in the universe, we discuss the constraint on the T-parity violation parameter based on the present dat Direct detection prospects are also discussed in some detail.

关键词： little Higgs dark matter time evolution

Highly efficient capture of thorium ion by citric acid-modified chitosan gels from aqueous solution

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Chinese Chemical Letters 2024年第5期35卷 361-365页

作者： Linshan peng Qihang peng Tianxiang Jin Zhirong Liu Yong qian State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China Jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and Devices East China University of TechnologyNanchang 330013China

A novel citric acid-modified chitosan gel(CSCA)was synthesized through a simple one-step process and was used to extract thorium ions from *** CSCA samples with varying chemical compositions were analyzed using SEM with mapping EDS,FT-IR,and static water contact angle measurements,and their adsorption behaviors were studied in *** results showed that the adsorption performance of CSCA improves with the increase of CA content in the *** possesses an impressive capacity for thorium adsorption of 279.8 mg/***,it showed an ultra-fast adsorption rate and reached equilibrium within 30 *** terms of recyclability,the CSCA still retained more than 86%of its initial adsorption capacity after 6 cycles of *** functional theory(DFT)analysis reveals that the good selectivity of this material towards thorium ions should be attributed to the high density of adsorption sites and strong interaction between carboxyl groups and thorium *** work could be beneficial in the design and synthesis of new polymer materials for extracting thorium.

关键词： Thorium Adsorption Citric acid Chitosan DFT calculation