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Light(Science & Applications) 2024年第7期13卷 1427-1440页

作者： Shulang Lin Li gong Zhiwei Huang Optical Bioimaging Laboratory Department of Biomedical EngineeringCollege of Design and EngineeringNational University of SingaporeSingapore 117576Singapore

We present a novel time-of-flight resolved Bessel light bullet-enabled stimulated Raman scattering(B2-SRS)microscopy for deeper tissue 3D chemical imaging with high resolution without a need for mechanical *** accomplish the tasks,we conceive a unique method to enable optical sectioning by generating the counterpropagating pump and Stokes Bessel light bullets in the sample,in which the group velocities of the Bessel light bullets are made ultraslow(e.g.,vg≈0.1c)and tunable by introducing programmable angular dispersions with a spatial light *** theoretically analyze the working principle of the collinear multicolor Bessel light bullet generations and velocity controls with the relative time-of-flight resolved detection for SRS 3D deep tissue *** have also built the B2-SRS imaging system and present the first demonstration of B2-SRS microscopy with Bessel light bullets for 3D chemical imaging in a variety of samples(e.g.,polymer bead phantoms,biological samples such as spring onion tissue and porcine brain)with high *** B2-SRS technique provides a>2-fold improvement in imaging depth in porcine brain tissue compared to conventional SRS *** method of optical sectioning in tissue using counter-propagating ultraslow Bessel light bullets developed in B2-SRS is generic and easy to perform and can be readily extended to other nonlinear optical imaging modalities to advance 3D microscopic imaging in biological and biomedical systems and beyond.

关键词： Bessel resolved propagating

Applications of mercury stable isotopes for tracing volcanism in the geologic record

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Science China Earth Sciences 2024年第5期67卷 1436-1458页

作者： Qing gong Ming-Xing LINg Wang ZHENg State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China School of Earth System Science Institute of Surface-Earth System ScienceTianjin UniversityTianjin 300072China

Mercury(Hg)enrichments in ancient sediments have been used as a proxy of volcanism,especially large igneous province(LIP)***,considering the existence of other potential Hg sources besides volcanoes and the diverse factors(e.g.,organic matters,clay minerals,sulfide minerals and Fe oxides)that can affect Hg sequestration,there are considerable uncertainties to simply regard sedimentary Hg anomalies as signatures of volcanic *** stable isotopes,a promising tool for tracing the origins and transformations of Hg,have been increasingly used for determining the causes of Hg spikes and understanding the geochemical behavior of Hg in the geologic *** date,lots of researches have applied Hg concentrations and Hg isotopes to identify LIP volcanisms linking with significant geological events such as mass extinctions,ocean anoxic events and other environmental perturbations that mainly occurred in the ***,the results in previous studies clearly show that not all Hg enrichments are derived from volcanic inputs,which emphasize the need for more caution in using Hg as a fingerprint of *** a better understanding of Hg isotopes in the future,there will be important implications for Hg isotopes to reconstruct volcanic activities in the rock records and their impacts on biological evolution.

关键词： Mercury stable isotopes Large igneous province Mass extinction event Ocean anoxic event

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BAD-FM:Backdoor Attacks Against Factorization-Machine Based Neural Network for Tabular Data Prediction

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Chinese Journal of Electronics 2024年第4期33卷 1077-1092页

作者： Lingshuo MENg Xueluan gong Yanjiao CHEN College of Electrical Engineering Zhejiang University School of Computer Science Wuhan University

Backdoor attacks pose great threats to deep neural network models. All existing backdoor attacks are designed for unstructured data(image, voice, and text), but not structured tabular data, which has wide real-world applications, e.g., recommendation systems, fraud detection, and click-through rate prediction. To bridge this research gap, we make the first attempt to design a backdoor attack framework, named BAD-FM, for tabular data prediction models. Unlike images or voice samples composed of homogeneous pixels or signals with continuous values, tabular data samples contain well-defined heterogeneous fields that are usually sparse and discrete. Tabular data prediction models do not solely rely on deep networks but combine shallow components(e.g., factorization machine, FM) with deep components to capture sophisticated feature interactions among fields. To tailor the backdoor attack framework to tabular data models, we carefully design field selection and trigger formation algorithms to intensify the influence of the trigger on the backdoored model. We evaluate BAD-FM with extensive experiments on four datasets, i.e.,HUAWEI, Criteo, Avazu, and KDD. The results show that BAD-FM can achieve an attack success rate as high as 100%at a poisoning ratio of 0.001%, outperforming baselines adapted from existing backdoor attacks against unstructured data models. As tabular data prediction models are widely adopted in finance and commerce, our work may raise alarms on the potential risks of these models and spur future research on defenses.

关键词： Adaptation models Systematics Frequency modulation Finance Predictive models Prediction algorithms Data models

Theoretical study on magnetocaloric effect and its electric-field regulation in CrI_(3)/metal heterostructure

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 134-141页

作者： Weiwei He Ziming Tang Qihua gong Min Yi Wanlin guo State Key Laboratory of Mechanics and Control for Aerospace Structures Key Laboratory for Intelligent Nano Materials and Devices of Ministry of EducationInstitute for Frontier ScienceNanjing University of Aeronautics and AstronauticsNanjing 210016China MIIT Key Laboratory of Aerospace Information Materials and Physics College of PhysicsNanjing University of Aeronautics and AstronauticsNanjing 211106China

The extraordinary properties of a heterostructure by stacking atom-thick van der Waals(vdW)magnets have been extensively ***,the magnetocaloric effect(MCE)of heterostructures that are based on monolayer magnets remains to be ***,we deliberate MCE of vd W heterostructure composed of a monolayer CrI_(3)and metal atomic layers(Ag,Hf,Au,and Pb).It is revealed that heterostructure engineering by introducing metal substrate can improve MCE of CrI_(3),particularly boosting relative cooling power to 471.72μJ m^(-2)and adiabatic temperature change to 2.1 K at 5 T for CrI_(3)/*** improved MCE is ascribed to the enhancement of magnetic moment and intralayer exchange coupling in CrI_(3)due to the CrI_(3)/metal heterointerface induced charge *** field is further found to tune MCE of CrI_(3)in heterostructures and could shift the peak temperature by around 10 K in CrI_(3)/Hf,thus manipulating the working temperature window of *** theoretical results could enrich the research on low-dimensional magnetocaloric materials.

关键词： magnetocaloric effect heterostructure metal substrate

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Hierarchical Control Strategy for Load Regulation Based on Stackelberg game Theory Considering Randomness

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 929-941页

作者： Tingyu Jiang Ping Ju C.Y.Chung Yuzhong gong College of Energy and Electrical Engineering Hohai UniversityNanjing 211100China Department of Electrical Engineering City University of Hong KongHong Kong CF624China Department of Electrical and Computer Engineering University of SaskatchewanSaskatoonSK S7N 5A9Canada CSEE IEEE

Demand response has been recognized as a valuable functionality of power systems for mitigating power *** paper proposes a hierarchical control strategy among the distribution system operator(DSO),load aggregators(LAs),and thermostatically controlled loads(TCLs);the strategy includes a scheduling layer and an executive layer to provide load *** the scheduling layer,the DSO(leader)offers compensation price(CP)strategies,and the LAs(followers)respond to CP strategies with available regulation power(ARP)*** of the DSO and LAs are modeled according to their behaviors during the load regulation *** game is adopted to capture interactions among the players and leader and to obtain the optimal strategy for each participant to achieve ***,considering inevitable random factors in practice,e.g.,renewable generation and behavior of users,two different stochastic models based on sample average approximation(SAA)and parameter modification are formulated with improved scheduling *** the executive layer,distributed TCLs are triggered based on strategies determined in the scheduling layer.A self-triggering method that does not violate user privacy is presented,where TCLs receive external signals from the LA and independently determine whether to alter their operation *** simulations are performed on the modified IEEE-24 bus system to verify effectiveness of the proposed strategy.

关键词： Demand response hierarchical control load regulation self-triggering method Stackelberg game

generic load regulation strategy for enhancing energy efficiency of chiller plants

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Building Simulation 2024年第8期17卷 1273-1287页

作者： Hang Wan Yuyang gong Shengwei Wang Yongjun Sun Tao Xu gongsheng Huang Department of Architecture and Civil Engineering City University of Hong KongHong KongChina Department of Building Environment and Energy Engineering Hong Kong Polytechnic UniversityHong KongChina School of Civil Engineering Guangzhou UniversityGuangzhouChina Shenzhen Research Institute of City University of Hong Kong ShenzhenChina

In many chiller plants,high coefficient of performance(COP)is only achieved at a few favorable part load ratios(PLRs),while the COP is low at many other non-favorable *** address this issue,this study proposes a generic load regulation strategy that aims to maintain chiller plants operating at high COP,particularly under non-favorable *** is achieved by incorporating thermal energy storage(TES)units and timely optimizing the charging and discharging power of the integrated TES *** optimal charging and discharging power is determined by solving a dynamic optimization problem,taking into account the performance constraints of the TES units and the chiller *** provide an overview of the energy-saving potential of the proposed strategy,a comprehensive analysis was conducted,considering factors such as building load profiles,COP/PLR curves of chillers,and attributes of the TES *** analysis revealed that the proposed load regulation strategy has the potential to achieve energy savings ranging from 5.7%to 10.8%for chiller plants with poor COPs under unfavorable PLRs,particularly in buildings with significant load variations.

关键词： load regulation thermal energy storage chiller plants building energy efficiency

Emergent symmetry in quantum phase transition:From deconfined quantum critical point to gapless quantum spin liquid

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Science Bulletin 2024年第2期69卷 190-196页

作者： Wen-Yuan Liu Shou-Shu gong Wei-Qiang Chen Zheng-Cheng gu Department of Physics The Chinese University of Hong KongHong KongChina Division of Chemistry and Chemical Engineering California Institute of TechnologyPasadena CA 91125USA School of Physical Sciences Great Bay UniversityDongguan 523000China great Bay Institute for Advanced Study Dongguan 523000China Department of Physics and Shenzhen Institute for Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Shenzhen Key Laboratory of Advanced Quantum Functional Materials and Devices Southern University of Science and TechnologyShenzhen 518055China

The emergence of exotic quantum phenomena in frustrated magnets is rapidly driving the development of quantum many-body physics,raising fundamental questions on the nature of quantum phase *** we unveil the behaviour of emergent symmetry involving two extraordinarily representative phenomena,i.e.,the deconfined quantum critical point(DQCP)and the quantum spin liquid(QSL)*** large-scale tensor network simulations,we study a spatially anisotropic spin-1/2 square-lattice frustrated antiferromagnetic(AFM)model,namely the J1x-J1y-J2 model,which contains anisotropic nearestneighbor couplings J1x,J1y and the next nearest neighbor coupling *** small J1y/J1x,by tuning J2,a direct continuous transition between the AFM and valence bond solid phase is *** growing J1y/J1x,a gapless QSL phase gradually emerges between the AFM and VBS *** observe an emergent O(4)symmetry along the AFM–VBS transition line,which is consistent with the prediction of DQCP *** surprisingly,we find that such an emergent O(4)symmetry holds for the whole QSL–VBS transition line as *** findings reveal the intrinsic relationship between the QSL and DQCP from categorical symmetry point of view,and strongly constrain the quantum field theory description of the QSL *** phase diagram and critical exponents presented in this paper are of direct relevance to future experiments on frustrated magnets and cold atom systems.

关键词： Tensor network Quantum phase transition Emergent symmetry Quantum spin liquid Deconfined quantum critical point Anisotropic

Dissipationless layertronics in axion insulator MnBi2Te4

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National Science Review 2024年第6期11卷 189-196页

作者： Shuai Li Ming gong Shuguang Cheng Hua Jiang X.C.Xie School of Physical Science and Technology Soochow University Institute for Advanced Study Soochow University International Center for Quantum Materials School of Physics Peking University Department of Physics Northwest University Interdisciplinary Center for Theoretical Physics and Information Sciences Fudan University Hefei National Laboratory

Surface electrons in axion insulators are endowed with a topological layer degree of freedom followed by exotic transport phenomena, e.g., the layer Hall effect. Here, we propose that such a layer degree of freedom can be manipulated in a dissipationless way based on the antiferromagnetic MnBi2Te4with tailored domain structure. This makes MnBi2Te4a versatile platform to exploit the ‘layertronics’ to encode, process and store information. Importantly, the layer filter, layer valve and layer reverser devices can be achieved using the layer-locked chiral domain wall modes. The dissipationless nature of the domain wall modes makes the performance of the layertronic devices superior to those in spintronics and valleytronics. Specifically, the layer reverser, a layer version of the Datta–Das transistor, also fills up the blank in designing the valley reverser in valleytronics. Our work sheds light on constructing new generation electronic devices with high performance and low-energy consumption in the framework of layertronics.

关键词： axion insulator MnBi2Te4 layertronics antiferromagnetic domain wall dissipationless transport

Post-treatment of Ti-MWW zeolite with potassium fluoride for propylene epoxidation

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Frontiers of Chemical Science and Engineering 2024年第8期18卷 37-47页

作者： Xintong Li Xianchen gong Jilong Wang Shengbo Jin Hao Xu Peng Wu State Key Laboratory of Petroleum Molecular&Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China

Epoxidation of propylene to propylene oxide(PO)with hydrogen peroxide(HPPO)is an environmentally friendly and cost-efficient process in which titanosilicates are used as ***-MWW is a potential industrial catalyst for this process,which involves the addition of HPPO to *** silanol groups generated during secondary crystallization unavoidably result in ring-opening of PO and inefficient decomposition of HPPO,which diminish the PO selectivity and the lifespan of *** address this issue,we conducted post-treatment modifications of the structured Bf-Ti-MWW catalyst with potassium fluoride aqueous *** quenching the silanol groups with potassium fluoride and implanting electron-withdrawing fluoride groups into the Ti-MWW framework,both the catalytic activity and HPPO utilization efficiency were ***,the ring opening reaction of PO was *** a continuous fixed-bed liquid-phase propylene epoxidation reaction,the KF-treated structured Ti-MWW catalyst displayed an exceptionally long lifespan of 2700 h,with a PO yield of 590 g·kg^(-1)·h^(-1).

关键词： titanosilicates Ti-MWW propylene epoxidation structured catalyst KF modification

Experimental and theoretical investigation of sulfur-doped g-C_(3)N_(4)nanosheets/FeCo_(2)O_(4)nanorods S-scheme heterojunction for photocatalytic H_(2)evolution

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Nano Research 2024年第9期17卷 8007-8016页

作者： Haitao Wang Lianglang Yu Jiahe Peng Jing Zou Weiping gong Jizhou Jiang School of Chemistry and Environmental Engineering School of Environmental Ecology and Biological EngineeringKey Laboratory of Green Chemical Engineering Process of Ministry of EducationEngineering Research Center of Phosphorus Resources Development and Utilization of Ministry of EducationNovel Catalytic Materials of Hubei Engineering Research CenterWuhan Institute of TechnologyWuhan 430205China guangdong Provincial Key Laboratory for Electronic Functional Materials and Devices Huizhou UniversityHuizhou 516007China

g-C_(3)N_(4)emerges as a promising metal-free semiconductor photocatalyst due to its cost-effectiveness,facile synthesis,suitable visible light response,and robust thermal ***,its practical application in photocatalytic hydrogen evolution reaction(HER)is impeded by rapid carrier recombination and limited light absorption *** this study,we successfully develop a novel g-C_(3)N_(4)-based step-scheme(S-scheme)heterojunction comprising two-dimensional(2D)sulfur-doped g-C_(3)N_(4)nanosheets(SCN)and one-dimensional(1D)FeCo_(2)O_(4)nanorods(FeCo_(2)O_(4)),demonstrating enhanced photocatalytic HER *** engineered SCN/FeCo_(2)O_(4)S-scheme heterojunction features a well-defined 2D/1D heterogeneous interface facilitating directed interfacial electron transfer from FeCo_(2)O_(4)to SCN,driven by the lower Fermi level of SCN compared to FeCo_(2)O_(4).This establishment of electron-interacting 2D/1D S-scheme heterojunction not only facilitates the separation and migration of photogenerated carriers,but also enhances visible-light absorption and mitigates electron-hole pair *** structure analysis and density functional theory calculations corroborate that the carrier migration in the SCN/FeCo_(2)O_(4)photocatalyst adheres to a typical S-scheme heterojunction mechanism,effectively retaining highly reactive photogenerated ***,the optimized SCN/FeCo_(2)O_(4)heterojunction exhibits a substantially high hydrogen production rate of 6303.5μmol·g^(-1)·h^(-1)under visible light excitation,which is 2.4 times higher than that of the ***,the conjecture of the S-scheme mechanism is confirmed by in situ XPS *** 2D/1D S-scheme heterojunction established in this study provides valuable insights into the development of high-efficiency carbon-based catalysts for diverse energy conversion and storage applications.

关键词： g-C_(3)N_(4) FeCo_(2)O_(4) S-scheme heterojunction photocatalytic hydrogen evolution reaction(HER)