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Source localization based on field signatures:Laboratory ultrasonic validation

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Journal of Electronic Science and Technology 2024年第3期22卷 47-56页

作者： Mahmoud Eissa Dmitry Sukhanov Department of Radiophysics Tomsk State UniversityTomsk634050Russia Higher institute for applied Sciences and Technology(HIAST) Damascus31983Syria

Location awareness in wireless networks is essential for emergency services,navigation,gaming,and many other *** article presents a method for source localization based on measuring the amplitude-phase distribution of the field at the base *** existing scatterers in the target area create unique scattered field interference at each source *** unique field interference at each source location results in a unique field signature at the base station which is used for source *** the proposed method,the target area is divided into a grid with a step of less than half the *** grid node is characterized by its field signature at the base *** signatures corresponding to all nodes are normalized and stored in the base station as fingerprints for source *** normalization of the field signatures avoids the need for time synchronization between the base station and the *** a source transmits signals,the generated field signature at the base station is normalized and then correlated with the stored *** maximum correlation value is given by the node to which the source is the *** simulations and results of experiments on ultrasonic waves in the air show that the ultrasonic source is correctly localized using broadband field signatures with one base station and without time *** proposed method is potentially applicable for indoor localization and navigation of mobile robots.

关键词： Base station Field signature Fingerprints Localization Ultrasonic frequencies

Understanding the corrosion and bio-corrosion behaviour of Magnesium composites – a critical review

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Journal of Magnesium and Alloys 2024年第3期12卷 890-939页

作者： Prithivirajan Sekar S.K.Panigrahi Department of Mechanical Engineering Indian Institute of Technology MadrasChennai600036India applied Magnesium Research Center Center of Excellence in Materials and Manufacturing for Futuristic MobilityIndian Institute of Technology MadrasChennai600036India

Realising the potential of Magnesium(Mg),several globally leading ventures have invested in the Mg industry,but their relatively poor corrosion resistance is a never ending saga till *** corrosion and bio-corrosion behaviour of Mg has gained research attention and still remains a hot topic in the application of automobile,aerospace and biomedical *** intrinsic high electrochemical nature of Mg limits their utilization in diverse *** scenario has prompted the development of Mg composites with an aim to achieve superior corrosion and bio-corrosion *** present review enlightens the influence of grain size(GS),secondary phase,texture,type of matrix and reinforcement on the corrosion and bio-corrosion behaviour of Mg ***,the corrosion and bio-corrosion behaviour of Mg composites manufactured by primary and secondary processing routes are ***,the comprehensive corrosion and bio-corrosion mechanisms of these Mg composites are ***,the individual role of GS,texture and corrosive medium on corrosion and bio-corrosion behaviour of Mg composites are clarified and *** challenges encountered,unanswered issues in this field are explained in detail and accordingly the scope for future research is *** review is presented from basic concrete background to advanced corrosion mechanisms with an aim of creating interest among the readers like students,researchers and industry experts from various research ***,the corrosion and bio-corrosion behaviour of Mg composites are critically reviewed for the first time to:(i)contribute to the body of knowledge,(ii)foster research and development,(iii)make breakthrough,and(iv)create life changing innovations in the field of Mg composite corrosion.

关键词： Corrosion Bio corrosion Magnesium alloys Magnesium composites Magnesium implants.

Towards an enhanced understanding of the particle size effect on conversion/alloying lithium-ion anodes

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Materials Futures 2024年第1期3卷 150-164页

作者： Jakob Asenbauer Dominik Horny Mayokun Olutogun Katrin Schulz Dominic Bresser Helmholtz institute Ulm(HIU) 89081 UlmGermany Karlsruhe institute of Technology(KIT) 76021 KarlsruheGermany institute for applied Materials(IAM) Karlsruhe Institute of Technology(KIT)76131 KarlsruheGermany Karlsruhe University of applied Sciences 76133 KarlsruheGermany

Conversion/alloying materials(CAMs)represent a potential alternative to graphite as a Li-ion anode active material,especially for high-power *** far,however,essentially all studies on CAMs have been dealing with nano-sized particles,leaving the question of how the performance(and the de-/lithiation mechanism in general)is affected by the particle ***,we comparatively investigate four different samples of Zn_(0.9)Co_(0.1)O with a particle size ranging from about 30 nm to a few *** results show that electrodes made of larger particles are more susceptible to fading due to particle displacement and particle *** results also show that the conversion-type reaction in particular is affected by an increasing particle size,becoming less reversible due to the formation of relatively large transition metal(TM)and alloying metal nanograins upon lithiation,thus hindering an efficient electron transport within the initial particle,while the alloying contribution remains essentially *** generality of these findings is confirmed by also investigating Sn_(0.9)Fe_(0.1)O_(2) as a second CAM with a substantially greater contribution of the alloying reaction and employing Fe instead of Co as a TM dopant.

关键词： particle size conversion alloying anode lithium-ion battery

Facile Synthesis of Polyisothioureas via Alternating Copolymerization of Aziridines and Isothiocayanates

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Chinese Journal of Polymer Science 2024年第3期42卷 292-298,I0005页

作者： Hao-Tian Zhang Ming-Xin Niu Qi Zhang Chen-Yang Hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Materials Science and Engineering Jilin UniversityChangchun 130025China School of applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Isothiourea is an important class of sulfur-containing molecules showing unique catalytic and biological activities. As such,polyisothiourea is envisioned to be an interesting type of polymer that potentially exhibits a number of interesting properties. However, there is no access to synthesizing well-defined polyisothiourea, and currently isothiourea-containing polymers are mainly prepared by immobilizing onto other polymer's side chain. Herein, we report the first facile synthesis of polyisothioureas via alternating copolymerization of aziridines and isothiocayanates. Mediated by the catalytic system of phosphazene superbases/alcohol, a broad scope of aziridines and isothiocayanates could be transformed into polyisothioureas with adjustable substitutions(11 examples). The structures of obtained polyisothioureas were fully characterized with ^(1)H-NMR, ^(13)C-NMR, and ^(1)H-^(13)C HMBC NMR. Moreover, the polyisothioureas show tunable thermal properties depending on substitutions on the isothiourea linkages. The novel structure of these polyisothioureas will enable a powerful platform for the discovery of nextgeneration functional plastics.

关键词： Polyisothioureas Alternative copolymer Aziridines Isothiocayanates

A Highly Efficient Ni/Al_(2)O_(3)-LaO_(x) Catalyst for the Reductive Amination of Furfural to Furfurylamine:the Promoting Effect of La

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Chemical Research in Chinese Universities 2024年第1期40卷 36-46页

作者： YANG Yinze ZHANG Liyan ZHOU Leilei CHENG Haiyang ZHAO Fengyu State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China School of applied Chemistry and Engineering University of Science Technology of ChinaHefei 230026P.R.China Jilin Province Key Laboratory of Green Chemistry and Process Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China

The reductive amination of furfural to furfurylamine is an important and still challenging topic in the field of biomass conversion. In this work, we prepared a series of Ni/Al_(2)O_(3)-LaO_(x) catalysts by co-precipitation method, the role of La played in promoting the catalytic performances of reductive amination furfural was discussed based on the changes in the electronic state of Ni species, acidity, and Ni particle size. The catalytic activity and the selectivity of furfurylamine are highly dependent on the surface properties and the structure of the catalyst. The addition of La promoted the amount of strong acidic sites and the H2dissociation and spillover on the surface, thus inducing the improvement of the catalytic activity and furfurylamine selectivity. The Ni/Al_(2)O_(3)-0.5LaO_(x)catalyst with suitable acid sites gave a high yield of furfurylamine (94.9%) under mild reaction conditions. Moreover, the catalyst could be recycled five times without significant loss in activity. The Ni/Al_(2)O_(3)-LaO_(x) catalyst is of great promise in the production of amines via reductive amination reaction.

关键词： Reductive amination Furfural Nickel catalyst Furfurylamine Lanthanum

Irrational-Behavior-Proof Conditions for Stochastic Games over Event Trees

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Journal of the Operations Research Society of China 2024年第1期12卷 243-263页

作者： Lei Wang Cui Liu Hong-Wei Gao Chong Lin School of Automation Institute of Complexity ScienceQingdao UniversityQingdao 266071ShandongChina School of Mathematics and Statistics Institute of Applied Mathematics of ShandongQingdao UniversityQingdao 266071ShandongChina

In this paper,the irrational-behavior-proof conditions in a class of stochastic dynamic games over event trees are *** kinds of irrational-behavior-proof conditions are proposed by the imputation distribution procedure,and their relationships are *** specific properties for the general transformation of characteristic functions are developed,based on which,the irrational-behavior-proof conditions are proved to be true in a transformed cooperative game.

关键词： Dynamic cooperative game Event tree Irrational-behavior-proof condition Imputation distribution procedure Transformation of characteristic function

Corrosion behavior of pure metals(Ni and Ti)and alloys(316H SS and GH3535)in liquid GaInSn

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Nuclear Science and Techniques 2024年第3期35卷 70-83页

作者： Jian-Hui Yu Hong-Xia Xu Xiang-Xi Ye Bin Leng Han-Xun Qiu Xing-Tai Zhou School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China Shanghai institute of applied Physics Chinese Academy of SciencesShanghai 201800China

In this study,the interactions between a Ga-based liquid metal,GaInSn,and several metal materials,including pure metals(Ni and Ti)and alloys(316H stainless steel(SS)and GH3535),at 650℃were *** aim was to evaluate the corrosion performance and select a suitable candidate material for use as a molten salt manometer diaphragm in thermal energy storage *** results indicated that the alloys(316H SS and GH3535)exhibited less corrosion than pure metals(Ni and Ti)in liquid ***-rich binary intermetallic compounds were found to form on the surfaces of all the tested metal materials exposed to liquid GaInSn,as a result of the decomposition of liquid GaInSn and its reaction with the constituent elements of the metal *** corrosion mechanism for all the tested materials exposed to liquid GaInSn was also investigated and proposed,which may aid in selecting the optimal candidate material when liquid GaInSn is used as the pressure-sensing medium.

关键词： Metal materials Liquid GaInSn Corrosion Intermetallic compounds Thermal energy storage systems

SMA-origami coupling:online configuration switches and stability property modulation

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International Journal of Smart and Nano Materials 2024年第1期15卷 21-41页

作者： Hai Zhou Hongbin Fang Zuolin Liu Jian Xu School of Aerospace Engineering and applied Mechanics Tongji UniversityShanghaiChina institute of AI and Robotics Fudan UniversityShanghaiChina Yiwu Research institute Fudan UniversityYiwuZhejiangChina

Active folding is a crucial requirement for practical applications of multi-stable origami ***,research on integrating active materials with origami structures to enable quick configuration switching and modulation of stability properties is still in its early *** advance the state-of-the-art,we designed a coupled structure comprising a stacked Miura-origami(SMO)structure and two Shape Memory Alloy(SMA)*** actuator is used for extruding the SMO structure while the other is used for retracting,thereby realizing bidirectional reversible active folding of the coupled *** the potential energy of the coupled structure shows that it can be switched between monostable and bistable by heating the SMA *** above findings are also confirmed by experiments conducted on a delicate SMO-SMA coupled structure *** activation of different actuators induces rapid configuration switching of the coupled structure,and the stability profile is qualitatively adjusted by designing the current loading profile to achieve steady-state temperature ***,this study provides a new approach to coupling origami structures with smart materials for active folding and presents a novel method to regulate the stability property of origami structures,thus promoting their practical applications.

关键词： Multistability bistable origami active folding smart material

S1-supported Pd@CeO_(2) quasi-core@shell materials as advanced catalysts for selective hydrogenation of furfural

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Chinese Chemical Letters 2024年第3期35卷 493-496页

作者： Xiang Chu Lingling Zhang Ke Wang Rui Zhang Xiao Wang Shuyan Song Hongjie Zhang State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Bare Pd metal nanoparticles invariably suffer from poor selectivity in furfural hydrogenation by forming flat configurations,with the aromatic ring of the substrate molecules parallel to the metal ***,we put forward a promising solution by using CeO_(2)as promoters to modify Pd nanoparticles for modulating the adsorption behaviors of furfural *** achieve the highly-desired ultra-small Pd@CeO_(2)core@shell nanostructure,a“constrained auto-redox”synthesis is developed,in which silicalite-1 supports play the key role of providing their surface as the landing place of PdO_(x)precursors for inhibiting the overgrowth and the *** the best of our knowledge,this is one of the smallest core@shell materials obtained from aqueous *** evaluated as catalysts,Pd@CeO_(2)/S-1 gives 98.9%conversion of furfural with 94.3%selectivity for furfural alcohol in 15 h,which is much better than that of Pd/S-1(88.6%conversion with 44.3%selectively).The DFT simulation reveals a strong interaction between the defects of CeO_(2)and the oxygen atom of the–CHO group in furfural molecules,which benefits the selective hydrogenation occurred in the–CHO group rather than the furan ring.

关键词： Core@shell Palladium Ceria Auto-redox synthesis Hydrogenation