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Journal of Environmental Sciences 2024年第4期138卷 709-718页

作者： Shuo hu Jianghao zhang Xueyan Chen Xiaoxiao Qin Jinshui Yao Changbin zhang School of materials Science&Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Formaldehyde(hChO)is a common indoor pollutant that is detrimental to human *** efficient removal has become an urgent demand to reduce the public health *** this work,Ag-mnO_(x)-based catalysts were prepared and activated under different atmosphere(i.e.,air,hydrogen(h_(2))and carbon monoxide(CO))for efficient oxidation of *** catalyst activated with CO(Ag/mn-CO)displayed the highest activity among the tested samples with 90% conversion at 100℃ under a gas space velocity of 75,000 mL/(g_(cat)·hr).Complementary characterizations demonstrate that CO reduction treatment resulted in synergically regulated content of surface oxygen on support to adsorb/activate hChO and size of Ag particle to dissociate oxygen to oxidize the adsorbed *** contrast,other catalysts lack for either abundant surface oxygen species or metallic silver with the appropriate particle size,so that the integrate activity is limited by one specific reaction *** study contributes to elucidating the mechanisms regulating the oxidation activity of Ag-based catalysts.

关键词： hChO oxidation Ag-mnO_(x)-based catalyst Activation condition Synergic regulation Surface oxygen Oxidized Ag

Transient long-range distance measurement by a Vernier spectral interferometry

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Photonics Research 2024年第6期12卷 1107-1114页

作者： LIANG XU KUN WANG ChEN LIU WENYING ChEN ChI zhang XINLIANG zhang Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Optics Valley Laboratory Wuhan 430074China

Rapid and long-range distance measurements are essential in various industrial and scientific applications,and among them,the dual-comb ranging system attracts great attention due to its high ***,the tem-poral asynchronous sampling results in the tradeoff between frame rate and ranging precision,and the non-ambiguity range(NAR)is also limited by the comb cycle,which hinders the further advancement of the dual-comb ranging *** this constraint,we introduce a Vernier spectral interferometry to improve the frame rate and NAR of the ranging ***,leveraging the dispersive time-stretch technology,the dual-comb interferometry becomes spectral ***,the asynchronous time step is unlimited,and the frame rate is improved to 100 ***,dual-wavelength bands are introduced to implement a Vernier spectral interferometry,whose NAR is enlarged from 1.5 m to 1.5 ***,this fast and long-range system also demonstrated high precision,with a 22.91-nm Allan deviation over 10-ms averaging *** a result,the proposed Vernier spectral interferometry ranging system is promising for diverse applications that necessitate rapid and extensive distance measurement.

关键词： interferometry spectral system

Long‐life lithium batteries enabled by a pseudo‐oversaturated electrolyte

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Carbon Energy 2024年第4期6卷 115-127页

作者： Youchun Yu Simeng Wang Juyan zhang Weiwei Qian Nana zhang Guangjie Shao haiyan Bian Yuwen Liu Lan zhang hebei Key Laboratory of Applied Chemistry College of Environmental and Chemical EngineeringYanshan UniversityQinhuangdaoChina Beijing Key Laboratory of Ionic Liquids Clean Process CAS Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijingChina haike Group Research Institute of Innovation&Technology DongyingChina Langfang Green Industrial Technology Center LangfangChina

The specific energy of Li metal batteries(LmBs)can be improved by using high‐voltage cathode materials;however,achieving long‐term stable cycling performance in the corresponding system is particularly challenging for the liquid ***,a novel pseudo‐oversaturated electrolyte(POSE)is prepared by introducing 1,1,2,2‐tetrafluoroethyl‐2,2,3,3‐tetrafluoropropyl ether(TTE)to adjust the coordination structure between diglyme(G2)and lithium bis(trifluoromethanesulfonyl)imide(LiTFSI).Surprisingly,although TTE shows little solubility to LiTFSI,the molar ratio between LiTFSI and G2 in the POSE can be increased to 1:1,which is much higher than that of the saturation state,1:*** and experimental results prove that TTE promotes closer contact of the G2 molecular with Li^(+)in the ***,it also participates in the formation of electrolyte/electrode *** electrolyte shows outstanding compatibility with both the Li metal anode and typical high‐voltage ***||Li symmetric cells show a long life of more than 2000 h at 1 mA cm^(−2),1 mAh cm^(−2).In the meantime,Li||LiNi_(0.8)Co_(0.1)mn_(0.1)O_(2)(NCm811)cell with the POSE shows a high reversible capacity of 134.8 mAh g^(−1 )after 900 cycles at 4.5 V,1 C *** concept of POSE can provide new insight into the Li^(+)solvation structure and in the design of advanced electrolytes for LmBs.

关键词： high voltage lithium metal batteries pseudo‐oversaturated electrolyte solid electrolyte interphases(SEI) solvation structure

Precipitation of multi-type nano-quasicrystals in a mg-Zn-Y alloy

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Journal of magnesium and Alloys 2024年第3期12卷 997-1008页

作者： W.Z.Wang X.Z.Zhou L.F.zhang h.Q.Ye Z.Q.Yang Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of ScienceShenyang 110016China Ji hua Laboratory Foshan 528251China Foshan University Foshan 528231China

mg-6Zn-1Y(at.%)ribbons with strengthening precipitates of multi-type nanoquasicrystals were prepared by melt-spinning followed by aging *** evolution of the rapidly solidified ribbons during isothermal aging was comprehensively studied using various electron microscopy *** new kinds of decagonal quasicrystals were formed in aged ribbons,in addition to precipitation of nanometer icosahedral ***-resolution observations reveal that both decagonal quasicrystals can be modeled by quasiperiodic tiling with decagonal clusters of 2.5 nm in diameter,but overlap of neighboring clusters in both decagonal quasicrystals is different from the Gummelt model observed in other quasicrystals.A shell composed of complex Laves mg-Zn domains was formed surrounding each decagonal quasicrystal precipitate upon prolonged *** addition,all kinds of nanoprecipitates exhibit excellent structure and size stability at 573 *** findings may have implications for not only fundamental studies about quasicrystals,but also microstructural manipulation of high-performance mg alloys.

关键词： Quasicrystal mg alloys Rapid solidification Scanning-transmission electron microscopy.

New Antenna Array Beamforming Techniques Based on hybrid Convolution/Genetic Algorithm for 5G and Beyond Communications

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Computer modeling in Engineering & Sciences 2024年第3期138卷 2749-2767页

作者： Shimaa m.Amer Ashraf A.m.Khalaf Amr h.hussein Salman A.Alqahtani mostafa h.Dahshan hossam m.Kassem Electronics and Communications Engineering Department Higher Institute of Engineering and TechnologyKafr ElsheikhEgypt Electronics and Electrical Communications Engineering Department Faculty of EngineeringMinia UniversityMiniaEgypt Electronics and Electrical Communications Engineering Department Faculty of EngineeringTanta UniversityTantaEgypt Electronics and Electrical Communications Engineering Department Faculty of EngineeringHorus University EgyptNew DamiettaEgypt Department of Computer Engineering College of computer and Information SciencesKing Saud UniversityRiyadh11543Saudi Arabia School of Computing Mathematics and EngineeringCharles Sturt UniversityBathurstNSW2795Australia

Side lobe level reduction(SLL)of antenna arrays significantly enhances the signal-to-interference ratio and improves the quality of service(QOS)in recent and future wireless communication systems starting from 5G up to ***,it improves the array gain and directivity,increasing the detection range and angular resolution of radar *** study proposes two highly efficient SLL reduction *** techniques are based on the hybridization between either the single convolution or the double convolution algorithms and the genetic algorithm(GA)to develop the Conv/GA andDConv/GA,*** convolution process determines the element’s excitations while the GA optimizes the element *** m elements linear antenna array(LAA),the convolution of the excitation coefficients vector by itself provides a new vector of excitations of length N=(2m−1).This new vector is divided into three different sets of excitations including the odd excitations,even excitations,and middle excitations of lengths m,m−1,andm,*** the same element spacing as the original LAA is used,it is noticed that the odd and even excitations provide a much lower SLL than that of the LAA but with amuch wider half-power beamwidth(hPBW).While the middle excitations give the same hPBWas the original LAA with a relatively higher *** the increased hPBWof the odd and even excitations,the element spacing is optimized using the ***,the synthesized arrays have the same hPBW as the original LAA with a two-fold reduction in the ***,for extreme SLL reduction,the DConv/GA is *** this technique,the same procedure of the aforementioned Conv/GA technique is performed on the resultant even and odd excitation *** provides a relatively wider hPBWthan the original LAA with about quad-fold reduction in the SLL.

关键词： Array synthesis convolution process genetic algorithm(GA) half power beamwidth(hPBW) linear antenna array(LAA) side lobe level(SLL) quality of service(QOS)

A Survey on Blockchain-Based Federated Learning:Categorization,Application and Analysis

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Computer modeling in Engineering & Sciences 2024年第6期139卷 2451-2477页

作者： Yuming Tang Yitian zhang Tao Niu Zhen Li Zijian zhang huaping Chen Long zhang School of Cyberspace Science&Technology Beijing Institute of TechnologyBeijing100081China School of Computer Science&Technology Beijing Institute of TechnologyBeijing100081China Southeast Institute of Information Technology Beijing Institute of TechnologyPutian351100China Qianxin Technology Group Co. Ltd.Beijing100044China

Federated Learning(FL),as an emergent paradigm in privacy-preserving machine learning,has garnered significant interest from scholars and engineers across both academic and industrial *** its innovative approach to model training across distributed networks,FL has its vulnerabilities;the centralized server-client architecture introduces risks of single-point ***,the integrity of the global model—a cornerstone of FL—is susceptible to compromise through poisoning attacks by malicious *** attacks and the potential for privacy leakage via inference starkly undermine FL’s foundational privacy and security *** these reasons,some participants unwilling use their private data to train a model,which is a bottleneck in the development and industrialization of federated *** technology,characterized by its decentralized ledger system,offers a compelling solution to these *** inherently prevents single-point failures and,through its incentive mechanisms,motivates participants to contribute computing ***,blockchain-based FL(BCFL)emerges as a natural progression to address FL’s *** study begins with concise introductions to federated learning and blockchain technologies,followed by a formal analysis of the specific problems that FL *** discusses the challenges of combining the two technologies and presents an overview of the latest cryptographic solutions that prevent privacy leakage during communication and incentives in *** addition,this research examines the use of BCFL in various fields,such as the Internet of Things and the Internet of ***,it assesses the effectiveness of these solutions.

关键词： Federated learning blockchain privacy-preserving

Special issue on electrochemical energy storage and conversion

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Frontiers in Energy 2024年第2期18卷 125-127页

作者： Yun ZhENG Gaixia zhang Sixu DENG Jiujun zhang Institute of New Energy materials and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China Department of Electrical Engineering École de Technologie Supérieure(ÉTS)Universitédu QuébecMontréalH3C 1K3Canada Department of Chemical and materials Engineering Concordia UniversityMontrealQC H3G 1M8Canada

The escalating global consumption of fossil fuels has significantly elevated the levels of CO_(2)in the atmosphere,leading to an undesirable global energy crisis and environmental *** deployment of renewable energy resources is crucial to mitigate these *** recent years,there has been noteworthy progress in electrochemical energy storage and conversion techniques and devices,including hydrogen energy and fuel cells,advanced energy storage and power batteries,and CO_(2)electrochemical conversion and utilization.

关键词： electrochemical energy elevated

Unveiling three-dimensional sea surface signatures caused by internal solitary waves:insights from the surface water ocean topography mission

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Journal of Oceanology and Limnology 2024年第3期42卷 709-714页

作者： Xudong zhang Xiaofeng LI Key Laboratory of Ocean Observation and Forecasting Key Laboratory of Ocean Circulation and WavesInstitute of OceanologyChinese Academy of SciencesQingdao 266071China

Internal solitary waves(ISW),characterized by large amplitude and long propagation distance,are widespread in global *** remote sensing images have played an essential role in studying ISWs,they mainly exploit two-dimensional image ***,with the launch of the surface water ocean topography(SWOT)satellite on December 16,2022,a unique opportunity has emerged to capture wide-swath three-dimensional ISW-induced sea surface *** this study,we examine ISWs in the Andaman Sea using data from the Ka-band Radar Interferometer(KaRIN),a crucial sensor onboard *** not only provides backscattering satellite images but also employs synthetic aperture interferometry techniques to retrieve wide-swath two-dimensional sea surface height *** observations in the Andaman Sea revealed the presence of ISWs characterized by dark-bright strips and surface elevation *** surface soliton has an amplitude of 0.32 m,resulting in an estimation of ISW amplitude of approximately 60 *** contrast to traditional two-dimensional satellite images or nadir-looking altimetry data,the SWOT mission’s capability to capture threedimensional sea surface information represents a significant *** breakthrough holds substantial promise for ISW studies,particularly in the context of ISW amplitude inversion.

关键词： internal solitary wave(ISW) surface water ocean topography(SWOT) altimeter

A convenient method for measuring gas-liquid volumetric mass transfer coefficient in micro reactors

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Chinese Chemical Letters 2024年第4期35卷 389-392页

作者： haoyang Wang Ronghao zhang Yanlun Ren Li zhang School of mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China

The research on gas-liquid multiphase reactions using micro reactors is becoming increasingly widespread, given their excellent mass transfer performance. Establishing an accurate and reliable method to measure the gas-liquid mass transfer performance of micro reactors is crucial for evaluating and optimizing the design of micro reactor structure. In this paper, the physical absorption method of aqueous solution-CO_(2) and the chemical absorption method of sodium carbonate solution-CO_(2) were proposed. By analyzing the chemical reaction equilibrium during the absorption process, the relationship between the mass transfer of CO_(2) and the solubility of hydroxide ions in the solution was established, and the total gas-liquid mass transfer coefficient was immediately obtained by measuring the p h value. The corresponding testing platform and process have been established based on the characteristics of the proposed method to ensure fast and accurate measurement. In addition, the chemical absorption method takes into account temperature factors that were not previously considered. The volumetric mass transfer coefficient measured by these two methods is in the same range as those measured by other methods using the same microchannel structure in previous literature. The methods have the advantages of low equipment cost, faster measurement speed, and simpler procedures, which can facilitate its wide application to the evaluation of the mass transfer performance and hence can guide the structure optimization of microchannel reactors.

关键词： Volumetric mass transfer coefficient measurement Gas-liquid two phase micro reactors Physical absorption Chemical absorption

CONVERGENCE ANALYSIS OF NONCONFORmING QUADRILATERAL FINITE ELEmENT mEThODS FOR NONLINEAR COUPLED SChRODINGER-hELmhOLTZ EQUATIONS

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Journal of Computational mathematics 2024年第4期42卷 979-998页

作者： Dongyang Shi houchao zhang School of mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China

The focus of this paper is on two novel linearized Crank-Nicolson schemes with nonconforming quadrilateral finite element methods(FEms)for the nonlinear coupled Schrodinger-helmholtz *** L^(2) and h^(1) estimates of orders O(h^(2)+τ^(2))and O(h^(2)+τ^(2))are derived respectively without any grid-ratio condition through the following two *** is that a time-discrete system is introduced to split the error into the temporal error and the spatial error,which leads to optimal temporal error estimates of order O(τ^(2))in L^(2) and the broken h^(1)-norms,as well as the uniform boundness of numerical solutions in L^(∞) *** other is that a novel projection is utilized,which can iron out the difficulty of the existence of the consistency *** leads to derive optimal spatial error estimates of orders O(h^(2))in L^(2)-norm and O(h)in the broken h^(1)-norm under the h^(2) regularity of the solutions for the time-discrete *** last,two numerical examples are provided to confirm the theoretical ***,h is the subdivision parameter,and τ is the time step.

关键词： Schrodinger-helmholtz equations Nonconforming FEms Linearized Crank-Nicolson scheme Optimal error estimates