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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

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

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

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

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

Microscopic and spectroscopic analysis of atmospheric iron-containing single particles in Lhasa,Tibet

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Journal of Environmental Sciences 2024年第7期141卷 40-50页

作者： Junyu Chen Daobin Zhang Yiran Fu Jinhu Wang Xiaomei Cui Ci-ren Qu-zong Qiangying Zhang Chan Jin Bu Duo School of Ecology and Environment Tibet UniversityLhasa 850000China Shanghai institute of applied Physics Chinese Academy of SciencesShanghai 201800China institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China

The Tibetan Plateau,known as the“Third Pole”,is currently in a state of perturbation caused by intensified human *** this study,56 samples were obtained at the five sampling sites in typical area of Lhasa city and their physical and chemical properties were investigated by TEM/EDS,STXM,and NEXAFS *** careful examination of 3387single particles,the results showed that Fe should be one of the most frequent metal *** Fe-containing single particles in irregular shape and micrometer size was about7.8%and might be mainly from local ***,the Fe was located on the subsurface of single particles and might be existed in the form of iron ***,the core-shell structure of iron-containing particles were about 38.8%and might be present as single-,dual-or triple-core shell structure and multi-core shell structure with the Fe/Si ratios of 17.5,10.5,2.9 and 1.2,***,iron and manganese were found to coexist with identical distributions in the single particles,which might induce a synergistic effect between iron and manganese in catalytic ***,the solid spherical structure of Fe-containing particles without an external layer were about 53.4%.The elements of Fe and Mn were co-existed,and might be presented as iron oxide-manganese oxide-silica ***,the ferrous and ferric forms of iron might be *** information can be valuable in expanding our understanding of Fe-containing particles in the Tibetan Plateau atmosphere.

关键词： Fe-containing single particle Irregular shape Core-shell structure Solid spherical structure Transmission electron microscopy Synchrotron X-ray microscopy

GraphSTGAN:Situation understanding network of slow-fast high maneuvering targets for maritime monitor services of IoT data

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Digital Communications and Networks 2024年第3期10卷 620-630页

作者： Guanlin Wu Haipeng Wang Yu Liu You He Shenzhen International Graduate School Tsinghua UniversityShenzhen518071China institute of Space Science and applied Technology Harbin Institute of TechnologyShenzhen518055China Department of Electronic Engineering Tsinghua UniversityBeijing100084China

With the rapid growth of the maritime Internet of Things(IoT)devices for Maritime Monitor Services(MMS),maritime traffic controllers could not handle a massive amount of data in *** unmanned MMS,one of the key technologies is situation ***,the presence of slow-fast high maneuvering targets and track breakages due to radar blind zones make modeling the dynamics of marine multi-agents difficult,and pose significant challenges to maritime situation *** order to comprehend the situation accurately and thus offer unmanned MMS,it is crucial to model the complex dynamics of multi-agents using IoT big ***,previous methods typically rely on complex assumptions,are plagued by unstructured data,and disregard the interactions between multiple agents and the spatial-temporal correlations.A deep learning model,Graph Spatial-Temporal Generative Adversarial Network(GraphSTGAN),is proposed in this paper,which uses graph neural network to model unstructured data and uses STGAN to learn the spatial-temporal dependencies and *** experiments show the effectiveness and robustness of the proposed method.

关键词： Internet of things Multi-agents Graph neural network Maritime monitoring services

Driver at 10 MJ and 1 shot/30 min for inertial confinement fusion at high gain:Efficient,compact,low-cost,low laser-plasma instabilities,beam color selectable from 2ω/3ω/4ω,applicable to multiple laser fusion schemes

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Matter and Radiation at Extremes 2024年第4期9卷 4-7页

作者：隋展蓝可 Shanghai institute of Laser Plasma China Academy of Engineering PhysicsShanghai 201800China instituteof applied Physics and Computational Mathematics Beijing 100094China

The achievement of ignition at the National Ignition Facility(NIF)has prompted a global wave of further research on inertial fusion energy(IFE).However,IFE requires a target gain G of 30-100,and it is hard to achieve fusion at such high gain with the energy,configuration,and technical approach of the ***,we present a conceptual design for a next-generation laser driver that is applicable to multiple laser fusion schemes and provides 10 MJ,2-3 PW at 3ω(or 2ω,in which case the energy and power can be higher),and one shot per 30 min,with the aim of achieving G>*** is also efficient,compact,and low in cost,and it has low susceptibility to laser-plasma instabilities.

关键词： applicable compact instabilities

A novel triple periodic minimal surface-like plate lattice and its data-driven optimization method for superior mechanical properties

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applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 217-238页

作者： Yanda WANG Yanping LIAN Zhidong WANG Chunpeng WANG Daining FANG State Key Laboratory for Turbulence and Complex Systems&Center for applied Physics and Technology College of EngineeringPeking UniversityBeijing 100871China institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China

Lattice structures can be designed to achieve unique mechanical properties and have attracted increasing attention for applications in high-end industrial equipment,along with the advances in additive manufacturing(AM)*** this work,a novel design of plate lattice structures described by a parametric model is proposed to enrich the design space of plate lattice structures with high connectivity suitable for AM *** parametric model takes the basic unit of the triple periodic minimal surface(TPMS)lattice as a skeleton and adopts a set of generation parameters to determine the plate lattice structure with different topologies,which takes the advantages of both plate lattices for superior specific mechanical properties and TPMS lattices for high connectivity,and therefore is referred to as a TPMS-like plate lattice(TLPL).Furthermore,a data-driven shape optimization method is proposed to optimize the TLPL structure for maximum mechanical properties with or without the isotropic *** this method,the genetic algorithm for the optimization is utilized for global search capability,and an artificial neural network(ANN)model for individual fitness estimation is integrated for high efficiency.A set of optimized TLPLs at different relative densities are experimentally validated by the selective laser melting(SLM)fabricated *** is confirmed that the optimized TLPLs could achieve elastic isotropy and have superior stiffness over other isotropic lattice structures.

关键词： lattice structure triple periodic minimal surface(TPMS) plate lattice structural optimization machine learning