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Energy & Environmental Materials 2024年第2期7卷 308-319页

作者： Guanghu He Huang Luo Chuanfang Yan Yuting Wan Dang Wu Hang Luo yuan Liu sheng Chen Key Laboratory of Polymeric Materials and Application Technology of Hunan Province College of ChemistryXiangtan UniversityXiangtan 411105China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Guangdong University of Petrochemical Technology Maoming 525000China

How to achieve synergistic improvement of permittivity(ε_(r))and breakdown strength(E_(b))is a huge challenge for polymer ***,for the first time,theπ-conjugated comonomer(MHT)can simultaneously promote theε_(r)and E_(b)of linear poly(methyl methacrylate)(PMMA)*** PMMA-based random copolymer films(P(MMA-co-MHT)),block copolymer films(PMMA-b-PMHT),and PMMA-based blend films were prepared to investigate the effects of sequential structure,phase separation structure,and modification method on dielectric and energy storage properties of PMMA-based dielectric *** a result,the random copolymer P(MMA-coMHT)can achieve a maximumε_(r)of 5.8 at 1 kHz owing to the enhanced orientation polarization and electron *** electron injection and charge transfer are limited by the strong electrostatic attraction ofπ-conjugated benzophenanthrene group analyzed by the density functional theory(DFT),the discharge energy density value of P(MMA-co-PMHT)containing 1 mol%MHT units with the efficiency of 80%reaches15.00 J cm^(-3)at 872 MV m^(-1),which is 165%higher than that of pure *** study provides a simple and effective way to fabricate the high performance of polymer dielectrics via copolymerization with the monomer of P-type semi-conductive polymer.

关键词： dielectric capacitor electrical properties energy density polymer dielectric semiconductor polymer

Super-resolution diffractive neural network for alloptical direction of arrival estimation beyond diffraction limits

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Light(Science & Applications) 2024年第8期13卷 1602-1614页

作者： sheng Gao Hang Chen Yichen Wang Zhengyang Duan Haiou Zhang Zhi Sun yuan Shen Xing Lin Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China

Wireless sensing of the wave propagation direction from radio sources lays the foundation for communication,radar,navigation,***,the existing signal processing paradigm for the direction of arrival estimation requires the radio frequency electronic circuit to demodulate and sample the multichannel baseband signals followed by a complicated computing process,which places the fundamental limit on its sensing speed and energy ***,we propose the super-resolution diffractive neural networks(S-DNN)to process electromagnetic(EM)waves directly for the DOA estimation at the speed of *** multilayer meta-structures of S-DNN generate super-oscillatory angular responses in local angular regions that can perform the all-optical DOA estimation with angular resolutions beyond the diffraction *** spatial-temporal multiplexing of passive and reconfigurable S-DNNs is utilized to achieve high-resolution DOA estimation over a wide field of *** S-DNN is validated for the DOA estimation of multiple radio sources over 5 GHz frequency bandwidth with estimation latency over two to four orders of magnitude lower than the state-of-the-art commercial devices in *** results achieve the angular resolution over an order of magnitude,experimentally demonstrated with four times,higher than diffraction-limited *** also apply S-DNN’s edge computing capability,assisted by reconfigurable intelligent surfaces,for extremely low-latency integrated sensing and communication with low power *** work is a significant step towards utilizing photonic computing processors to facilitate various wireless sensing and communication tasks with advantages in both computing paradigms and performance over electronic computing.

关键词： beyond optical network

Effect of electrolyte cation-mediated mechanism on electrocatalytic carbon dioxide reduction

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Chinese Chemical Letters 2024年第7期35卷 139-146页

作者： yuan Dong Mutian Ma Zhenyang Jiao sheng Han Likun Xiong Zhao Deng Yang Peng Soochow Institute of Energy and Material Innovations College of EnergyJiangsu Key Laboratory of Advanced Carbon Materials and Wearable Energy TechnologiesSoochow UniversitySoochow 215006China Jiangsu Key Laboratory of Advanced Negative Carbon Technologies Soochow UniversitySoochow 215123China School of Chemistry and Chemical Engineering Shihezi UniversityShihezi 832003China School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai 201418China

The steep reduction in costs and systematic optimization of renewable electricity has ignited an intensifying interest in harnessing electroreduction of carbon dioxide(CO_(2)RR)for the generation of chemicals and *** focus of research over the past few decades has been on the optimization of the electrode and the electrolyte ***,cation species in the latter have recently been found to dramatically alter the selectivity of CO_(2)RR and even their catalytic activity by multiple orders of *** a result,the selection of cations is a critical factor in designing catalytic interfaces with high selectivity and efficiency for targeted *** decision-making regarding cation selection relies on a comprehensive understanding of prevailing electrolyte effect models that have been used to elucidate observed experimental *** this perspective,we review the hypotheses that explain how electrolyte cations influence CO_(2)RR by mechanisms such as through tuning of the interfacial electric field,buffering of the local pH,stabilization of the key intermediates and regulation of the interfacial *** endeavor is to elucidate the molecular mechanisms underpinning cation effects,thus fostering the evolution of more holistic and universally applicable predictive *** this regard,we highlight the current challenges in this area of research,while also identifying potential avenues for future investigations.

关键词： CO_(2)electrocatalytic reduction Cation effects Catalytic mechanisms Catalytic interfaces Electric double layer

Changes in global land surface frozen ground and freeze-thaw processes during 1950-2020 based on ERA5-Land data

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Advances in Climate Change Research 2024年第2期15卷 265-274页

作者： Yong YANG Ren-sheng CHEN Yong-Jian DING Hong-yuan LI Zhang-Wen LIU Qilian Alpine Ecology and Hydrology Research Station Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection College of Resources and EnvironmentLinyi UniversityLinyi 276000China

Frozen ground(FG)plays an important role in global and regional climates and environments through changes in land freeze-thaw processes,which have been conducted mainly in different ***,the changes in land surface freeze-thaw processes under climate change on a global scale are still *** on ERA5-Land hourly land skin temperature data,this study evaluated changes in the global FG area,global land surface first freeze date(FFD),last freeze date(LFD)and frost-free period(FFP)from 1950 to *** results show that the current FG areas(1991-2020 mean)in the Northern Hemisphere(NH),Southern Hemisphere(SH),and globe are 68.50×10^(6),9.03×10^(6),and 77.53×10^(6)km^(2),which account for 72.4%,26.8%,and 60.4%of the exposed land(excluding glaciers,ice sheets,and water bodies)in the NH,SH and the globe,respectively;further,relative to 1951-1980,the FG area decreased by 1.9%,8.8%,and 2.8%,*** FG at lower latitudes degrades to intermittently FG,and intermittently FG degrades to non-frozen ground,which caused the global FG boundary to retreat to higher latitudes from 1950 to *** annual FG areas in the NH,SH,and globe all show significant decreasing trends(p<0.05)from 1950 to 2020 at-0.32×10^(6),-0.22×10^(6),and-0.54×10^(6)km^(2)per decade,*** FFP prolongation in the NH is mainly influenced by LFD advance,while in the SH it is mainly controlled by FFD *** prolongation trend of FFP in the NH(1.34 d per decade)is larger than that in the SH(1.15 d per decade).

关键词： Frozen ground Freeze-thaw processes Frost-free period First freeze date Global warming

C-F insertion reaction sheds new light on the construction of fluorinated compounds

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Chinese Chemical Letters 2024年第8期35卷 163-169页

作者： Dong-sheng Deng Su-Qin Tang Yong-Tu yuan Ding-Xiong Xie Zhi-yuan Zhu Yue-Mei Huang Yun-Lin Liu Henan Key Laboratory of Function-Oriented Porous Materials and College of Chemistry and Chemical EngineeringLuoyang Normal UniversityLuoyang 471934China School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou 510006China Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

The atom-economical C-F insertion chemistry is emerged as a promising technology for the synthesis of various fluorinated scaffolds,which have wide applications both in the academic and the industrial *** past three years have witnessed rapid developments in this *** highlight provides an overview on the evolution according to the fluorinating agents used.

关键词： C-F insertion Benzyl fluoride Acyl fluoride gem-Difluorocyclopropane Fluorinated scaffold

Comparison of the effect of different external electrodes on discharge plasma-assisted diffusion flame stabilization

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Plasma Science and Technology 2024年第10期26卷 123-132页

作者： Siyin zhou Xiang LIU Wansheng NIE Shuhui yuan Space Engineering University Beijing 101416People’s Republic of China

To optimize the design of plasma injectors,the influence of different external electrodes on plasma-assisted flame stabilization was assessed by using a nonequilibrium plasma injector flame control *** electrical characteristics of the injector,flame structure parameters,flame intensity,discharge power,and cost-to-effectiveness ratio under different external electrodes(four mesh electrodes and one copper foil electrode)were analyzed using electrical and optical *** results show that reducing the mesh size of the external electrode leads to a decrease in breakdown *** with a ceramic dielectric barrier-based injector,an injector with a quartz dielectric barrier produces a higher breakdown voltage under the same *** the same actuation voltage,the discharge current increases as the mesh size of the external electrode decreases,and combustion is enhanced by the discharge plasma;therefore,it is better to adopt a smaller mesh hole size to realize good flame stabilization under a lower actuation ***,under the studied working conditions,reducing the mesh hole size of the external electrode increases the cost-to-effectiveness ratio of plasma injector-based flame ***,considering the cost-to-effectiveness ratio and the weight of the injector,an external electrode with a larger mesh hole size should be chosen,which contradicts the above rule.

关键词： flame stabilization alternating current driven dielectric barrier discharge plasma injector plasma-assisted combustion external electrode

Local Adaptive Gradient Variance Attack for Deep Fake Fingerprint Detection

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Computers, Materials & Continua 2024年第1期78卷 899-914页

作者： Chengsheng yuan Baojie Cui Zhili zhou Xinting Li Qingming Jonathan Wu Engineering Research Center of Digital Forensics Ministry of EducationNanjing University of Information Science and TechnologyNanjing210044China School of Computer Science Nanjing University of Information Science and TechnologyNanjing210044China Institute of Artificial Intelligence and Blockchain Guangzhou UniversityGuangzhou510006China School of International Relations National University of Defense TechnologyNanjing210039China Department of Electrical and Computer Engineering University of WindsorWindsorN9B 3P4Canada

In recent years,deep learning has been the mainstream technology for fingerprint liveness detection(FLD)tasks because of its remarkable ***,recent studies have shown that these deep fake fingerprint detection(DFFD)models are not resistant to attacks by adversarial examples,which are generated by the introduction of subtle perturbations in the fingerprint image,allowing the model to make fake *** of the existing adversarial example generation methods are based on gradient optimization,which is easy to fall into local optimal,resulting in poor transferability of adversarial *** addition,the perturbation added to the blank area of the fingerprint image is easily perceived by the human eye,leading to poor visual *** response to the above challenges,this paper proposes a novel adversarial attack method based on local adaptive gradient variance for *** ridge texture area within the fingerprint image has been identified and designated as the region for perturbation ***,the images are fed into the targeted white-box model,and the gradient direction is optimized to compute gradient ***,an adaptive parameter search method is proposed using stochastic gradient ascent to explore the parameter values during adversarial example generation,aiming to maximize adversarial attack *** results on two publicly available fingerprint datasets show that ourmethod achieves higher attack transferability and robustness than existing methods,and the perturbation is harder to perceive.

关键词： FLD adversarial attacks adversarial examples gradient optimization transferability

Engineering classification recycling of spent lithium-ion batteries through pretreatment:a comprehensive review from laboratory to scale-up application

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Rare Metals 2024年第3期43卷 915-941页

作者： Shu-Xuan Yan You-zhou Jiang Xiang-Ping Chen Lu yuan Ting-Ting Min Yu Cao Wan-Li Peng Tao zhou Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China College of Chemistry and Chemical Engineering Hunan Normal UniversityChangsha 410083China School of Public Policy and Management Tsinghua UniversityBeijing 100084China China Nonferrous Metal Industry's Foreign Engineering and Construction Co. LtdBeijing 100029China

The lithium-ion batteries(LIBs)have been widely equipped in electric/hybrid electric vehicles(EVs/HEVs)and the portable electronics due to their excellent electrochemical ***,a large number of retired LIBs that consist of toxic substances(e.g.,heavy metals,electrolytes)and valuable metals(e.g.,Li,Co)will inevitably flow into the waste stream,and their incineration or landfill treatment will cause severe risks to ecosystem and human *** sustainable and efficient treatment or recycling of valuable resources from spent LIBs should be fully recognized for environmental and resource *** one of the most important processes for spent LIBs recycling,the pretreatment is an indispensable step,which is directly related to the subsequent metal extraction and separation *** considerable progresses have been made regarding the pretreatment technologies,there are few summarized reports concerning critical processes of spent LIBs recycling,especially combination of currently available recycling technologies with industrialized applications during ***,comprehensive review of the current prevailing pretreatment technologies in laboratory to existing scale-up applications is quite necessary to reveal cutting-edge development in the field of *** this review,the current pretreatment technologies are systematically categorized and introduced,along with critical *** review focused on the various options for pretreatment processes itself,instead of general spent LIBs recycling technologies without the focused topics that have been sophisticatedly reviewed by previous ***,the deactivation,discharge,dismantling,separation,liberation of active material and electrolyte treatment have been summarized with the in-depth discussion of the technology development and current status of each ***,current states of industrial development are also reviewed and discussed for the development of

关键词： Spent lithium-ion batteries(LIBs) Recycling Pretreatment Valuable metals Cutting-edge technologies Industrialized application

Epidermal visualized health monitoring system based on stretchable and washable TPU hybrid conductive microtextiles

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Rare Metals 2024年第7期43卷 3185-3193页

作者： Jing-Bo yuan Zhi-Hong Feng Dong-Chan Li Yang Luo Yun-Lei zhou School of Chemical Engineering Hebei University of Technology Engineering Research Center of Chemical Technology for Efficient Utilization of Seawater ResourcesMinistry of EducationTianjin 300401China National Key Laboratory of Application Specific Integrated Circuit Shijiazhuang050000China Department of Materials ETH Zürich8093 ZurichSwitzerland Hangzhou Institute of Technology Xidian UniversityHangzhou 311231China

Electronic textiles,an emerging class of electronic technology,offer exciting opportunities for seamless integration with the human *** applications have been developed based on electronic ***,researches on integrating multiple electronic textilebased devices are still *** this study,we present a system integrated with an electrocardiogram monitoring sensor and an electroluminescence device based on stretchable and washable conductive micro *** signal is acquired by an electrocardiograph amplifier and displayed by a dual-color electroluminescence device based on the processed *** integrated electronic device has excellent moisture permeability and comfort for long-term *** system reported in this study opens a new avenue for the application of electronic textiles in health monitoring,robotic prosthetics,and competitive sports.

关键词： Conductive microtextile Textile composite Electronic textile Electroluminescent displays

Highly Aromatic Norditerpenoid Heterodimers and Monomers from Trigonostemon fragilis

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Engineering 2024年第7期38卷 144-154页

作者： Jun-Su zhou Long Cheng yuan Gao Zhan-Peng Ge Bin zhou Jing-Ya Li Jin-Xin Zhao Jian-Min Yue State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Shandong Laboratory of Yantai Drug Discovery Bohai Rim Advanced Research Institute for Drug DiscoveryYantai 264117China

Four new norditerpenoid heterodimers with different dimerization patterns-namely,trigofragiloids A-C(denoted as compounds 1-3)and(+)-and(-)-trigofragiloid D(compound 4)-and three new phenanthrenone norditerpenoids-namely,trigofragiloids E-G(compounds 5-7)-were isolated from Trigonostemon *** 1 and 2 feature a novel heterodimeric carbon skeleton formed by the conjugation of a tetra-norditerpenoid and an ennea-norditerpenoid;they have been identified as class 2 atropisomers by means of quantum chemical *** 3 is an unprecedented phenylpropanoid-norditerpenoid adduct with a new dimerization ***(+)-and(-)-4 are the first example of S-shaped 1,4-dioxane-fused norditerpenoid *** by the structure elucidation of compound 4,two co-occurring analogues,actephilol A and epiactephilol A,were structurally revised as a pair of geometrical isomers and were identified as two pairs of enantiomers,(+)-and(-)-8 and(+)-and(-)-9,*** structures were characterized using a combined ***,compound 7 exhibits remarkable adenosine triphosphate-citrate lyase(ACLY)inhibition with a halfmaximal inhibition concentration(IC50)value of(0.46±0.11)lmol·L^(-1),as active as the positive control BMS-303141,and a molecular docking study offers deep insight into the interaction between compound 7 and ACLY.

关键词： Norditerpenoid heterodimer Trigonostemon fragilis Euphorbiaceae Trigofragiloid Structural revision Adenosine triphosphate-citrate lyase(ACLY) inhibitory activity