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Macroscopic model and statistical model to characterize electromagnetic information of a digital coding metasurface

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National Science Review 2024年第03期11卷 159-171页

作者： Rui Wen Shao Jun Wei Wu Zheng Xing Wang Hui Xu Han Qing Yang Qiang Cheng Tie Jun Cui Institute of Electromagnetic Space Southeast University State Key laboratory of Millimeter Waves Southeast University Peng Cheng laboratory Pazhou laboratory(Huangpu)

A digital coding metasurface is a platform connecting the digital space and electromagnetic wave space, and has therefore gained much attention due to its intriguing value in reshaping wireless channels and realizing new communication architectures. Correspondingly, there is an urgent need for electromagnetic information theory that reveals the upper limit of communication capacity and supports the accurate design of metasurface-based communication systems. To this end, we propose a macroscopic model and a statistical model of the digital coding metasurface. The macroscopic model uniformly accommodates both digital and electromagnetic aspects of the meta-atoms and predicts all possible scattered fields of the digital coding metasurface based on a small number of simulations or measurements. Full-wave simulations and experimental results show that the macroscopic model is feasible and accurate. A statistical model is further proposed to correlate the mutual coupling between meta-atoms with covariance and to calculate the entropy of the equivalent currents of digital coding metasurface. These two models can help reconfigurable intelligent surfaces achieve more accurate beamforming and channel estimation, and thus improve signal power and coverage. Moreover, the models will encourage the creation of a precoding codebook in metasurface-based direct digital modulation systems, with the aim of approaching the upper limit of channel capacity. With these two models, the concepts of current space and current entropy, as well as the analysis of information loss from the coding space to wave space, is established for the first time, helping to bridge the gap between the digital world and the physical world, and advancing developments of electromagnetic information theory and new-architecture wireless systems.

关键词： electromagnetic information theory current entropy current space digital coding metasurface macroscopic model statistical model

Atomic-resolution Interfacial Microstructure and Thermo-electro-magnetic Energy Conversion Performance of Gd/Bi0.5Sb1.5Te3 Composites

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Energy & Environmental Materials 2024年第4期7卷 355-363页

作者： Chengshan Liu Wenjie Xu Ping Wei Shaoqiu Ke Wenjun Cui Longzhou Li Dong Liang Xianfeng Ye Tiantian Chen Xiaolei Nie Wanting Zhu Wenyu Zhao Qingjie Zhang State Key laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Foshan Xianhu laboratory of the Advanced Energy Science and Technology Guangdong laboratory

Thermo-electro-magnetic materials with simultaneously large magnetocaloric(MC) and thermoelectric (TE) effects are the core part for designing TE/MC all-solid-state cooling *** MC phase with TE material is an effective ***,the elemental diffusion and chemical reaction occurring at the two-phase interfaces could significantly impair the cooling performance.

关键词： interfacial reaction magnetocaloric performance thermoelectric performance thermo-electro-magnetic materials

Rapid and controllable in-situ self-assembly of main-group metal nanofilms for highly efficient CO_(2)electroreduction to liquid fuel in flow cells

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Nano Research 2024年第6期17卷 5718-5725页

作者： Miao Wang Huaizhu Wang Yaoda Wang Junchuan Liang Mengfei Zhu Jiarui Li Zuoxiu Tie Zhong Jin State Key laboratory of Coordination Chemistry MOE Key Laboratory of Mesoscopic ChemistryMOE Key Laboratory of High Performance Polymer Materials and TechnologyJiangsu Key Laboratory of Advanced Organic MaterialsTianchang New Materials and Energy Technology Researc

The electrocatalytic reduction of CO_(2)is a promising pathway to generate renewable fuels and ***,its advancement is impeded by the absence of electrocatalysts with both high selectivity and ***,we present a scalable in-situ thermal evaporation technique for synthesizing series of Bi,In,and Sn nanofilms on carbon felt(CF)substrates with a high-aspect-ratio *** resulting main-group metal nanofilms exhibit a homogeneously distributed and highly exposed catalyst surface with ample active sites,thereby promoting mass transport and ad-/desorption of reaction *** from the unique fractal morphology,the Bi nanofilms deposited on CF exhibit optimal catalytic activities for CO_(2)electroreduction among the designed metal nanofilms electrodes,with the highest Faradaic efficiency of 96.9%for formate production at−1.3 V *** hydrogen electrode(RHE)in *** an industrially relevant current density of 221.4 mA·cm−2 in flow cells,the Bi nanofilms retain a high Faradaic efficiency of 81.7%at−1.1 V(***)and a good long-term stability for formate ***,a techno-economic analysis(TEA)model shows the potential commercial viability of electrocatalytic CO_(2)conversion into formate using the Bi nanofilms *** results offer a green and convenient approach for in-situ fabrication of stable and inexpensive thin-film catalysts with a fractal structure applicable to various industrial settings.

关键词： CO_(2)electroreduction non-noble metal nanofilms flow cells efficiency and selectivity techno-economic analysis

The m^(6)A regulator KIAA1429 stabilizes RAB27B mRNA and promotes the progression of chronic myeloid leukemia and resistance to targeted therapy

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Genes & Diseases 2024年第2期11卷 993-1008页

作者： Fangyi Yao Fangmin Zhong Junyao Jiang Ying Cheng Shuai Xu Jing Liu Jin Lin Jing Zhang Shuqi Li Meiyong Li Yanmei Xu Bo Huang Xiaozhong Wang Jiangxi Province Key laboratory of laboratory Medicine Jiangxi Provincial Clinical Research Center for Laboratory MedicineDepartment of Clinical LaboratoryThe Second Affiliated Hospital of Nanchang UniversityNanchangJiangxi 330006China

Chronic myeloid leukemia(CML)is a common adult *** the acute phase of the disease and the adverse effects of anti-cancer treatments can lead to a poor *** N6-methyladenine(m^(6)A)modification plays an important regulatory role in various physiological and pathological ***1429 is a known m^(6)A regulator,but the biological role of KIAA1429 in CML is *** this study,we observed that the m^(6)A levels and KIAA1429 expression were significantly up-regulated in patients with blast phase ***,KIAA1429 regulated the total level of RNA m^(6)A modification in the CML cells and promoted the malignant biological behaviors of CML cells,including proliferation,migration,and imatinib *** KIAA1429 in CML cells reduced the stability of RAB27B mRNA through the m^(6)A/YTHDF1 axis,consequently inhibiting CML proliferation and drug efflux,ultimately increasing the sensitivity of CML cells to ***,the knockdown of RAB27B also inhibited the proliferation and drug resistance of CML cells and promoted their ***,a recently developed anti-cancer agent,suppressed the expression of KIAA1429 and CML cell proliferation and promoted cell *** also inhibited the tumorigenesis of CML cells in *** combined use of rucaparib and imatinib enhanced the sensitivity of CML cells to *** study provides evidence that elevated KIAA1429 expression in the blast phase of CML enhances the stability of RAB27B mRNA through the m^(6)A/YTHDF1 axis to up-regulate RAB27B expression,thereby promoting CML *** exerts inhibitory effects on KIAA1429 expression and thus reduces CML progression.

关键词： Chronic myeloid leukemia KIAA1429 N6-methyladenine RAB27B Rucaparib YTHDF1

Bioinspired 3D flexible devices and functional systems

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National Science Review 2024年第3期11卷 271-295页

作者： Xu Cheng Zhangming Shen Yihui Zhang Applied Mechanics laboratory Department of Engineering Mechanics Tsinghua University laboratory of Flexible Electronics Technology Tsinghua University

Flexible devices and functional systems with elaborated three-dimensional(3D) architectures can endow better mechanical/electrical performances, more design freedom, and unique functionalities, when compared to their two-dimensional(2D) counterparts. Such 3D flexible devices/systems are rapidly evolving in three primary directions, including the miniaturization, the increasingly merged physical/artificial intelligence and the enhanced adaptability and capabilities of heterogeneous *** challenges exist in this emerging research area, such as relatively poor controllability in the locomotion of soft robotic systems, mismatch of bioelectronic interfaces, and signal coupling in multi-parameter sensing. By virtue of long-time–optimized materials, structures and processes, natural organisms provide rich sources of inspiration to address these challenges, enabling the design and manufacture of many bioinspired 3D flexible devices/systems. In this Review, we focus on bioinspired 3D flexible devices and functional systems, and summarize their representative design concepts, manufacturing methods, principles of structure-function relationship and broad-ranging applications. Discussions on existing challenges, potential solutions and future opportunities are also provided to usher in further research efforts toward realizing bioinspired 3D flexible devices/systems with precisely programmed shapes,enhanced mechanical/electrical performances, and high-level physical/artificial intelligence.

关键词： bioinspired designs biomimetic 3D structures 3D flexible electronics 3D functional systems direct 3D manufacture 2D-to-3D assembly

Micelle-directed self-assembly of single-crystal-like mesoporous stoichiometric oxides for high-performance lithium storage

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National Science Review 2024年第4期11卷 195-205页

作者： Yanhua Wan Changyao Wang Xingmiao Zhang Yang Yin Mengmeng Liu Bing Ma Linlin Duan Yuzhu Ma Wei Zhang Changlin Zheng Dongliang Chao Fei Wang Yongyao Xia Wei Li Department of Chemistry Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials State Key Laboratory of Molecular Engineering of Polymers College of Chemistry and Materials ScienceFudan University State Key laboratory of Surface Physics and Department of Physics Fudan University

Due to their uncontrollable assembly and crystallization process,the synthesis of mesoporous metal oxide single crystals remains a formidable ***,we report the synthesis of single-crystal-like mesoporous Li2TiSiO5by using soft micelles as *** key lies in the atomic-scale self-assembly and step-crystallization processes,which ensure the formation of single-crystal-like mesoporous Li2TiSiO5microparticles via an oriented attachment growth mechanism under the confinement of an in-situ formed carbon *** mesoporous Li2TiSiO5anode achieves a superior rate capability(148 mAh g-1at5.0 A g-1) and outstanding long-term cycling stability(138 mAh g-1after 3000 cycles at 2.0 A g-1) for lithium storage as a result of the ultrafast Li+diffusion caused by penetrating mesochannels and nanosized crystal frameworks（5-10 nm）.In comparison,bulk Li2TiSiO5exhibits poor rate capability and cycle performance due to micron-scale diffusion *** method is very simple and reproducible,heralding a new way of designing and synthesizing mesoporous single crystals with controllable frameworks and chemical functionalities.

关键词： mesoporous materials micelles single-crystal-like Li2TiSiO5 lithium-ion batteries

Moiré superlattices arising from growth induced by screw dislocations in layered materials

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Chinese Physics B 2024年第7期33卷 72-77页

作者：田伏钰 Muhammad Faizan 贺欣孙远慧张立军 State Key laboratory of Integrated Optoelectronics Key laboratory of Automobile Materials of MOE and College of Materials Science and Engineering Jilin UniversityChangchun 130012China Suzhou laboratory Suzhou 215123China

Moiré superlattices(MSLs) are modulated structures produced from homogeneous or heterogeneous two-dimensional layers stacked with a twist angle and/or lattice mismatch. Enriching the methods for fabricating MSL and realizing the unique emergent properties are key challenges in its investigation. Here we recommend that the spiral dislocation driven growth is another optional method for the preparation of high quality MSL samples. The spiral structure stabilizes the constant out-of-plane lattice distance, causing the variations in electronic and optical properties. Taking SnS_(2) MSL as an example, we find prominent properties including large band gap reduction(~ 0.4 e V) and enhanced optical activity. Firstprinciples calculations reveal that these unusual properties can be ascribed to the locally enhanced interlayer interaction associated with the Moiré potential modulation. We believe that the spiral dislocation driven growth would be a powerful method to expand the MSL family and broaden their scope of application.

关键词： Moirésuperlattices interlayer interaction spiral dislocation layered materials

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Bimetallic CoNi single atoms supported on three-dimensionally ordered mesoporous chromia: highly active catalysts for n-hexane combustion

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Green Energy & Environment 2024年第7期9卷 1122-1137页

作者： Xiuqing Hao Yuxi Liu Jiguang Deng Lin Jing Jia Wang Wenbo Pei Hongxing Dai Beijing Key laboratory for Green Catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution Control Key Laboratory of Advanced Functional Materials Education Ministry of China Laboratory of Catalysis Chemistry and Nanoscience Department of Chemical Engineering Faculty of Environment and Life Beijing University of Technology

Developing the alternative supported noble metal catalysts with low cost,high catalytic efficiency,and good resistance toward carbon dioxide and water vapor is critically demanded for the oxidative removal of volatile organic compounds （VOCs）.In this work,we prepared the mesoporous chromia-supported bimetallic Co and Ni single-atom （Co1Ni1/meso-Cr2O3） and bimetallic Co and Ni nanoparticle (CoNPNiNP/mesoCr2O3) catalysts adopting the one-pot polyvinyl pyrrolidone （PVP）-and polyvinyl alcohol （PVA）-protecting approaches,*** results indicate that the Co1Ni1/meso-Cr2O3catalyst exhibited the best catalytic activity for n-hexane (C6H14) combustion (T50%and T90%were 239 and 263℃ at a space velocity of 40,000 mL g-1h-1;apparent activation energy and specific reaction rate at 260℃ were 54.7 kJ mol-1and 4.3×10-7mol g-1cats-1,respectively),which was associated with its higher (Cr5++Cr6+) amount,large n-hexane adsorption capacity,and good lattice oxygen mobility that could enhance the deep oxidation of n-hexane,in which Ni1was beneficial for the enhancements in surface lattice oxygen mobility and low-temperature reducibility,while Co1preferred to generate higher contents of the high-valence states of chromium and surface oxygen species as well as adsorption and activation of n-hexane.n-Hexane combustion takes place via the Mars van Krevelen（MvK） mechanism,and its reaction pathways are as follows:n-hexane→olefins or 3-hexyl hydroperoxide→3-hexanone,2-hexanone or 2,5-dimethyltetrahydrofuran→2-methyloxirane or 2-ethyl-oxetane→acrylic acid→COx→CO2and H2O.

关键词： Three-dimensional ordered mesoporous chromium oxide Supported bimetallic single-atom catalyst Cobalt−nickel single atoms n -Hexane combustion Catalytic reaction mechanism

Chain Dynamics Heterogeneity in Plasticized Poly(vinyl butyral)(PVB) as Elucidated by Solid-State NMR

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Chinese Journal of Polymer Science 2024年第1期42卷 113-124,I0010页

作者： Jing Lv Xu Chen Zi-Shuo Wu Ya-Hui Li Wei Chen National Synchrotron Radiation laboratory Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmCAS Key Laboratory of Soft Matter ChemistryUniversity of Scienceand Technology of ChinaHefei 230026China

The chain dynamics heterogeneity of the poly(vinyl butyral)(PVB) plasticized by triethylene glycol bis(2-ethylhexa noate)(TEG-EH) was investigated by various solid-state NMR *** plasticized PVB shows two domains in distinct molecular dynamics differences,namely,rigid and soft domains,where the latter is the plasticizer-rich *** time domain low field NMR was first used to investigate the dynamics heterogeneity of the plasticized PVB,and the results show the decreasing activated energy of components in the soft domain of plasticized PVB(E_a=20.2 kJ/mol) as compared with that of the pristine one(E_a=24.3 kJ/mol).Detailed dynamics heterogeneity was obtained by high-field NMR with site-specific *** quadrupole-echo ~2H-NMR was adopted to elucidate the dynamics heterogeneity of the vinyl alcohol(VA) units,where only the hydroxyl group of VA is *** ~1H-^(13)C WISE NMR spectra show that there is not much difference in the mobility of the VB unit in PVB with and without plasticizer,whereas the glass transition temperature differed by approximately 53℃.This is further supported by Torchia's T_1 relaxation *** origin of such an unusual phenomenon is attributed to the critical role of the remaining VA(~22%) in the soft domain,where the VA units locally aggregate through hydrogen ***,the existence of a mobility gradient in the VB unit has been ***,the mobility difference for VB with different stereo-geometry(meso or racemic conformation) is observed for the first *** indicates the importance of modulating the ratio of meso over racemic VB for controlling the macroscopic perfo rmance of PVB.

关键词： Poly(vinyl butyral) Dynamics heterogeneity Plasticizer Solid state NMR

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