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Molecular-based porous polymers with precise sites for photoreduction of carbon dioxide

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Chinese Chemical Letters 2025年第1期36卷 201-213页

作者： Wei-Jia wang Kaihong Chen College of Biological and Chemical Engineering Zhejiang University of Science and TechnologyHangzhou 310023China The Institute of Green Chemistry and Engineering School of Chemistry and Chemical EngineeringNanjing UniversitySuzhou 215163China

Photocatalytic CO_(2)reduction reaction(CO_(2)RR)is one of the promising strategies for sustainably producing solar *** precise identification of catalytic sites and the enhancement of photocatalytic CO_(2)conversion is imperative yet quite *** critical review summarizes recent advances in porous photo-responsive polymers,including covalent organic frameworks(COFs),covalent triazine frameworks(CTFs),and conjugated microporous polymers(CMPs),those can be rationally designed from the molecular level for visible-light-driven photocatalytic CO_(2)***,special emphasis is placed on how the well-defined active sites on these polymers can influence their properties and photocatalytic *** precise regulation and control of microenvironments and electronic properties of metal active centers are crucial for boosting catalytic efficiency and selectivity,as well as for the design of better photocatalysts for CO_(2)reduction.

关键词： Carbon dioxide reduction Photocatalysis Porous polymers Well-defined catalytic sites Molecular level

Experimental investigation on the anti-detonation performance of composite structure containing foam geopolymer backfill material

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Defence Technology(防务技术) 2025年第1期43卷 304-318页

作者： Hang Zhou Hujun Li Zhen wang Dongming Yan Wenxin wang Guokai Zhang Zirui Cheng Song Sun Mingyang wang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China College of Civil Engineering and Architecture Zhejiang UniversityHangzhou 310058China Institute for Composites Science Innovation School of Materials Science and EngineeringZhejiang UniversityHangzhou310027China School of Safety Science and Engineering(School of Emergency Management) Nanjing University of Science and TechnologyNanjing 210094China State Key Laboratory of Disaster Prevention and Mitigation of Explosion and Impact Army Engineering University of PLANanjing 210014China

The compression and energy absorption properties of foam geopolymers increase stress wave attenuation under explosion impacts,reducing the vibration effect on the *** tests were conducted using several composite structure models,including a concrete lining structure(CLS)without foam geopolymer and six foam geopolymer composite structures(FGCS)with different backfill parameters,to study the dynamic response and wave dissipation mechanisms of FGCS under explosive ***,strain,and vibration responses at different locations were synchronously *** damage modes and dynamic responses of different models were compared,and how wave elimination and energy absorption efficiencies were affected by foam geopolymer backfill parameters was *** results showed that the foam geopolymer absorbed and dissipated the impact energy through continuous compressive deformation under high strain rates and dynamic loading,reducing the strain in the liner structure by 52%and increasing the pressure attenuation rate by 28%.Additionally,the foam geopolymer backfill reduced structural vibration and liner deformation,with the FGCS structure showing 35%less displacement and 70%less acceleration compared to the *** FGCS model with thicker,less dense foam geopolymer backfill,having more pores and higher porosity,demonstrated better compression and energy absorption under dynamic impact,increasing stress wave attenuation *** analyzing the stress wave propagation and the compression characteristics of the porous medium,it was concluded that the stress transfer ratio of FGCS-ρ-579 was 77%lower than that of CLS,and the transmitted wave energy was 90%*** results of this study provide a scientific basis for optimizing underground composite structure interlayer parameters.

关键词： Explosion load Composite structure Geopolymer foam Energy absorption

Radical dehydroxymethylative fluorination of aliphatic primary alcohols and diverse functionalization ofα-fluoroimides via BF_(3)·OEt_(2)-catalyzed C-F bond activation

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Chinese Chemical Letters 2025年第1期36卷 239-243页

作者： Peng wang Jianjun wang Ni Song Xin Zhou Ming Li Molecular Synthesis Center Key Laboratory of Marine MedicineChinese Ministry of EducationSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts Pilot National Laboratory for Marine Science and TechnologyQingdao 266237China

Ag_(2)CO_(3)-promoted dehydroxymethylative fluorination of aliphatic alcohols has been achieved with Selectfluor as both oxidant and fluorine *** reaction involvesβ-fragmentation of primary alkoxy radicals,followed by the fluorination of the resulting C-centered radical *** transformation proceeds under mild reaction conditions and exhibits a broad substrate scope,thus opening up a new entrance to the synthesis of fluorinated constructs includingα-fluoroimides and 1-fluoroalkyl benzoates as well as secondary and tertiary alkyl fluorides like versatile 2-fluoro-2-alkyl 1,3-propandiol *** divergent functionalization of the obtainedα-fluoroimides enables an efficient access to amine derivatives through C-F bond activation under the action of BF_(3)·OEt_(2).

关键词： Dehydroxymethylative fluorination Alkoxy radicals β-Fragmentation Silver catalysis C-F Bond activation

Lattice-mismatch-induced formation of defect-rich Pd-Cu alloy nanocages for enhanced formic acid oxidation activity

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Science China Chemistry 2025年第2期68卷 481-491页

作者： Zhaojun Liu Zhengyan wang Zhaoyu wang Hao Yuan Yuke Bai Xiaoxiao wang Zerui Mu Chunxia Wu Kai Liu Zhun Hu Chuanbo Gao Sate Key Laboratory of Multiphase Flow in Power Engineering Frontier Institute of Science and TechnologyXi’an Jiaotong UniversityXi’an 710049China Institute of Industrial Catalysis School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an 710049China

Crystallographic defects in noble metal nanocrystals are recognized as highly active catalytic sites,significantly enhancing activities in many important *** their importance,synthesizing noble metal nanocrystals with a high density of defects poses a considerable synthetic ***,we present a novel lattice mismatch-induced formation mechanism to create high-density defects in noble metal *** approach takes advantage of lattice mismatch to enable nonepitaxial nucleation and growth of a noble metal on a foreign metal substrate,forming abundant noble metal crystallites with random lattice orientations not dictated by the substrate *** these crystallites grow extensively,they merge,forming numerous grain boundaries and yielding defect-rich noble metal ***-rich alloy nanocrystals can also be synthesized through a subsequent vacancy-diffusion alloying *** take defective PdCu alloy nanocages as an example and demonstrate the effectiveness of crystallographic defects in enhancing catalytic performance of noble metal *** nanocages exhibit superior activity in the electrocatalytic formic acid oxidation reaction,which is 1.6 times greater than their defect-free *** strategy offers a new avenue for creating defect-rich noble metal nanocrystals as highly efficient catalysts for a wide array of catalytic applications.

关键词： noble metal nanocrystals defects non-epitaxial growth electrocatalysis formic acid oxidation reaction

Near-perfect replication on amorphous alloys through active force modulation based on machine learning/neural network parameter prediction

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 177-187页

作者： Senkuan Meng Zheng wang Ruisong Zhu Ruijie Liu Jiang Ma Lina Hu Weihua wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJinan 250061China College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060China Songshan Lake Materials Laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China

As a microforming technique,micro/nano-structural replication possesses advantages of high precision and *** the remarkable superplasticity in the supercooled liquid region,amorphous alloys or metallic glasses(MGs)are regarded as ideal materials for miniature ***,due to the intrinsic metastable nature of supercooled liquids,the design of imprinting processes for MGs poses a *** the past,process parameters have largely relied on trial-and-error *** this work,a low-frequency active force modulation system is employed to apply a stable,precise,and real-time feedback stress field for imprinting of MG ***-frequency vibrations can facilitate the filling of microstructures on the template surface by reducing the effective viscosity of the supercooled *** the dataset composed of orthogonal experiments,a machine learning strategy based on back-propagation(BP)neural networks was utilized to construct a 3D parameter space for temperature,stress,and time,and to predict the corresponding filling ***,the optimal combination of imprinting process parameters was identified,and its filling ratio was experimentally validated to reach as high as *** near-perfect replication of microstructures confirms the superiority of the active force modulation system and the data-driven strategy of machine learning-assisted parameter *** the same time,this one-step microforming process provides a new approach to addressing the accuracy-cost trade-off dilemma in precision manufacturing.

关键词： metallic glass amorphous alloy microforming imprinting machine learning

Impact of coking plant to heavy metal characteristics in groundwater of surrounding areas:Spatial distribution,source apportionment and risk assessments

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Journal of Environmental Sciences 2025年第3期149卷 688-698页

作者： Congqing wang Wanjun wang Chaowang Shixing Ren Yingjun Wu Meicheng Wen Guiying Li Taicheng An Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control Guangdong Hong Kong-Macao Joint Laboratory for Contaminants Exposure and HealthInstitute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Guangzhou Key Laboratory Environmental Catalysis and Pollution Control Key Laboratory of City Cluster Environmental Safety and Green developmentSchool of Environmental Science and EngineeringGuangdong University of TechnologyGuangzhou 510006China

Coking industry is a potential source of heavy metals(HMs)***,its impacts to the groundwater of surrounding residential areas have not been well *** study investigated the pollution characteristics and health risks of HMs in groundwater nearby a typical coking *** HMs including Fe,Zn,Mo,As,Cu,Ni,Cr,Pb and Cd were *** average concentration of total HMswas higher in the nearby area(244.27μg/L)than that of remote area away the coking plant(89.15μg/L).The spatial distribution of pollution indices including heavy metal pollution index(HPI),Nemerow index(NI)and contamination degree(CD),all demonstrated higher values at the nearby residential areas,suggesting coking activity could significantly impact the HMs distribution *** sources of HMs were identified by Positive Matrix Factorization(PMF)model,which indicated coal washing and coking emission were the dominant sources,accounted for 40.4%,and 31.0%,*** ingestionwas found to be the dominant exposure pathway with higher exposure dose to children than *** quotient(HQ)values were below 1.0,suggesting negligible non-carcinogenic health risks,while potential carcinogenic risks were from Pb and Ni with cancer risk(CR)values>10−*** Carlo simulation matched well with the calculated results with HMs concentrations to be the most sensitive *** study provides insights into understanding how the industrial coking activities can impact the HMs pollution characteristics in groundwater,thus facilitating the implement of HMs regulation in coking industries.

关键词： Coking industry Heavy metal Groundwater Spatial distribution Source apportionment Monte Carlo simulation

AI-Enhanced Secure Data Aggregation for Smart Grids with Privacy Preservation

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Computers, Materials & Continua 2025年第1期82卷 799-816页

作者： Congcong wang Chen wang Wenying Zheng Wei Gu School of Software Nanjing University of Information Science and TechnologyNanjing210044China School of Information Science and Engineering Zhejiang Sci-Tech UniversityHangzhou310018China State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025China School of Computer Science and Technology(School of Artificial Intelligence) Zhejiang Sci-Tech UniversityHangzhou310018China School of Computer Science(School of Cyber Science and Engineering) Nanjing University of Information Science and TechnologyNanjing210044China

As smart grid technology rapidly advances,the vast amount of user data collected by smart meter presents significant challenges in data security and privacy *** research emphasizes data security and user privacy concerns within smart ***,existing methods struggle with efficiency and security when processing large-scale *** efficient data processing with stringent privacy protection during data aggregation in smart grids remains an urgent *** paper proposes an AI-based multi-type data aggregation method designed to enhance aggregation efficiency and security by standardizing and normalizing various data *** approach optimizes data preprocessing,integrates Long Short-Term Memory(LSTM)networks for handling time-series data,and employs homomorphic encryption to safeguard user *** also explores the application of Boneh Lynn Shacham(BLS)signatures for user *** proposed scheme’s efficiency,security,and privacy protection capabilities are validated through rigorous security proofs and experimental analysis.

关键词： Smart grid data security privacy protection artificial intelligence data aggregation

Surface element design of nanomaterials considering surface curvature dependence

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Acta Mechanica Sinica 2025年第1期41卷 42-53页

作者： Yongchao Zhang Lian wang Fangxin wang Bin Li Xiaofan Gou College of Mechanics and Materials Hohai UniversityNanjing 211100China College of Architectural Science and Engineering Yangzhou UniversityYangzhou 225127China School of Mechanics and Photoelectric Physics Anhui University of Science and TechnologyHuainan 232001China

Nanomaterials have garnered recognition for their notable surface effects and demonstration of superior mechanical *** studies on the surface effects of nanomaterials,employing the finite element method,often relied on simplified twodimensional models due to theoretical ***,these simplified models inadequately represent the mechanical properties of nanomaterials and fail to capture the substantial impact of surface effects,particularly the curvature dependence of *** study applies the principle of minimum energy and leverages the Steigmann-Ogden surface theory of nanomaterials to formulate a novel finite element surface element that comprehensively accounts for surface *** conducted an analysis of the stress distribution and deformation characteristics of four typical 2D and 3D nanomaterial *** accuracy of the developed surface element and finite element calculation method was verified through comparison with established *** resulting finite element model provides a robust and compelling scientific approach for accurately predicting the mechanical performance of nanomaterials.

关键词： Nanomaterials Surface effect Surface element curvature dependence Finite element method

Detection of Perfect Stealthy Attacks on Cyber-Physical Systems Subject to Measurement Quantizations: A Watermark-Based Strategy

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IEEE/CAA Journal of Automatica Sinica 2025年第1期12卷 114-125页

作者： Yu-Ang wang Zidong wang Lei Zou Bo Shen Hongli Dong the College of Information Science and Technology Donghua University the Engineering Research Center of Digitalized Textile and Fashion Technology Ministry of Education IEEE the College of Electrical Engineering and Automation Shandong University of Science and Technology the Department of Computer Science Brunel University London Uxbridge the Sanya Offshore Oil and Gas Research Institute Northeast Petroleum University the Artificial Intelligence Energy Research Institute Northeast Petroleum University Heilongjiang Provincial Key Laboratory of Networking and Intelligent Control Northeast Petroleum University

In this paper, the attack detection problem is investigated for a class of closed-loop systems subjected to unknownbutbounded noises in the presence of stealthy attacks. The measurement outputs from the sensors are quantized before transmission.A specific type of perfect stealthy attack, which meets certain rather stringent conditions, is taken into account. Such attacks could be injected by adversaries into both the sensor-toestimator and controller-to-actuator channels, with the aim of disrupting the normal data flow. For the purpose of defending against these perfect stealthy attacks, a novel scheme based on watermarks is developed. This scheme includes the injection of watermarks(applied to data prior to quantization) and the recovery of data(implemented before the data reaches the estimator).The watermark-based scheme is designed to be both timevarying and hidden from adversaries through incorporating a time-varying and bounded watermark signal. Subsequently, a watermark-based attack detection strategy is proposed which thoroughly considers the characteristics of perfect stealthy attacks,thereby ensuring that an alarm is activated upon the occurrence of such attacks. An example is provided to demonstrate the efficacy of the proposed mechanism for detecting attacks.

关键词： Attack detection cyber-physical systems (CPSs) perfect stealthy attacks watermark-based strategy