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Frontiers in Energy 2024年第2期18卷 206-222页

作者： cheng yuan Shiming zhang Jiujun zhang Institute for Sustainable Energy/college of Sciences Shanghai UniversityShanghai 200444China

Platinum(Pt)-based materials are still the most efficient and practical catalysts to drive the sluggish kinetics of cathodic oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFcs).However,their catalysis and stability performance still need to be further improved in terms of corrosion of both carbon support and Pt catalyst particles as well as Pt loading *** on the developed synthetic strategies of alloying/nanostructuring Pt particles and modifying/innovating supports in developing conventional Pt-based catalysts,Pt single-atom catalysts(Pt SAcs)as the recently burgeoning hot materials with a potential to achieve the maximum utilization of Pt are comprehensively reviewed in this *** design thoughts and synthesis of various isolated,alloyed,and nanoparticlecontained Pt SAcs are *** single-atomic Pt coordinating with non-metals and alloying with metals as well as the metal-support interactions of Pt single-atoms with carbon/non-carbon supports are emphasized in terms of the ORR activity and stability of the *** advance further research and development of Pt SAcs for viable implementation in PEMFcs,various technical challenges and several potential research directions are outlined.

关键词： oxygen reduction electrocatalysis Pt singleatom catalysts conventional Pt-based catalysts design thoughts and synthesis metal-support interactions

Integration of Multiple Spectral Data via a Logistic Regression Algorithm for Detection of crop Residue Burned Areas:A case Study of Songnen Plain,Northeast china

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chinese Geographical Science 2024年第3期34卷 548-563页

作者： zhang Sumei zhang yuan ZHAO Hongmei college of Mining and Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China

The burning of crop residues in fields is a significant global biomass burning activity which is a key element of the terrestrial carbon cycle,and an important source of atmospheric trace gasses and *** estimation of cropland burned area is both crucial and challenging,especially for the small and fragmented burned scars in *** we developed an automated burned area mapping algorithm that was implemented using Sentinel-2 Multi Spectral Instrument(MSI)data and its effectiveness was tested taking Songnen Plain,Northeast china as a case using satellite image of *** employed a logistic regression method for integrating multiple spectral data into a synthetic indicator,and compared the results with manually interpreted burned area reference maps and the Moderate-Resolution Imaging Spectroradiometer(MODIS)McD64A1 burned area *** overall accuracy of the single variable logistic regression was 77.38%to 86.90%and 73.47%to 97.14%for the 52TcQ and 51TYM cases,*** comparison,the accuracy of the burned area map was improved to 87.14%and 98.33%for the 52TcQ and 51TYM cases,respectively by multiple variable logistic regression of Sentind-2 *** balance of omission error and commission error was also *** integration of multiple spectral data combined with a logistic regression method proves to be effective for burned area detection,offering a highly automated process with an automatic threshold determination *** method exhibits excellent extensibility and flexibility taking the image tile as the operating *** is suitable for burned area detection at a regional scale and can also be implemented with other satellite data.

关键词： crop residue burning burned area Sentinel-2 Multi Spectral Instrument(MSI) logistic regression Songnen Plain,china

Optimization of biofuel supply chain integrated with petroleum refineries under carbon trade policy

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Frontiers of chemical Science and Engineering 2024年第3期18卷 113-122页

作者： Wenhui zhang Yiqing Luo Xigang yuan chemical Engineering Research center School of Chemical Engineering and TechnologyTianjin UniversityTianjin300350China State Key Laboratory of chemical Engineering Tianjin UniversityTianjin300350China

The use of fossil fuels results in significant carbon dioxide *** have been increasingly adopted as sustainable alternatives to fossil fuel to address this environmental *** petroleum refineries into biofuel supply chains is an effective approach to mitigating greenhouse gas emissions and improving environmental *** this study,an integrated supply chain optimization framework was established,considering the carbon trade *** addition,a mixed-integer nonlinear programming model was developed to optimize the selection of biomass suppliers,construction of pretreatment plants and biorefineries,integration of petroleum refineries,and selection of transportation routes with the objective of minimizing the total annual *** example is presented to illustrate the applicability of the *** optimization results show that integrating petroleum refineries into biofuel supply chains effectively mitigates carbon *** trade policies can have a direct impact on the total annual cost and carbon emissions of the supply chain.

关键词： renewable energy biofuel supply chain carbon trade policy

N-doped graphene quantum dot-decorated N-TiO2/P-doped porous hollow g-c_(3)N_(4) nanotube composite photocatalysts for antibiotic photodegradation and H2 production

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 165-178页

作者： Jingshu yuan Yao zhang Xiaoyan zhang Junjie zhang Shen’gen zhang Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Xi’an Fanyi University Xi’an 710105China Shunde Graduate School of University of Science and Technology Beijing Foshan 528399China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao SAR 820000China

Exclusive responsiveness to ultraviolet light (~3.2 eV) and high photogenerated charge recombination rate are the two primary drawbacks of pure TiO_(2). We combined N-doped graphene quantum dots (N-GQDs), morphology regulation, and heterojunction construction strategies to synthesize N-GQD/N-doped TiO_(2)/P-doped porous hollow g-c_(3)N_(4) nanotube (PcN) composite photocatalysts (denoted as G-TPcN). The optimal sample (G-TPcN doped with 0.1wt% N-GQD, denoted as 0.1% G-TPcN) exhibits significantly enhanced photoabsorption, which is attributed to the change in bandgap caused by elemental doping (P and N), the improved light-harvesting resulting from the tube structure, and the upconversion effect of N-GQDs. In addition, the internal charge separation and transfer capability of0.1% G-TPcN are dramatically boosted, and its carrier concentration is 3.7, 2.3, and 1.9 times that of N-TiO_(2), PcN, and N-TiO_(2)/PcN(TPcN-1), respectively. This phenomenon is attributed to the formation of Z-scheme heterojunction between N-TiO_(2) and PcNs, the excellent electron conduction ability of N-GQDs, and the short transfer distance caused by the porous nanotube structure. compared with those of N-TiO_(2), PcNs, and TPcN-1, the H2 production activity of 0.1%G-TPcN under visible light is enhanced by 12.4, 2.3, and 1.4times, respectively, and its ciprofloxacin (cIP) degradation rate is increased by 7.9, 5.7, and 2.9 times, respectively. The optimized performance benefits from excellent photoresponsiveness and improved carrier separation and migration efficiencies. Finally, the photocatalytic mechanism of 0.1% G-TPcN and five possible degradation pathways of cIP are proposed. This study clarifies the mechanism of multiple modification strategies to synergistically improve the photocatalytic performance of 0.1% G-TPcN and provides a potential strategy for rationally designing novel photocatalysts for environmental remediation and solar energy conversion.

关键词： N-doped TiO_(2) N-doped graphene quantum dots P-doped g-c_(3)N_(4) porous hollow nanotube heterojunction photocatalysis

controllable split polarization singularities for ultra-precise displacement sensing

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Photonics Research 2024年第7期12卷 1478-1484页

作者： JIAKANG ZHOU HAIXIANG MA SHUOSHUO zhang WU yuan cHANGJUN MIN XIAOcONG yuan YUQUAN zhang Nanophotonics Research centre Institute of Microscale Optoelectronics&State Key Laboratory of Radio Frequency Heterogeneous IntegrationShenzhen UniversityShenzhen 518060China Research center for Humanoid Sensing Research Institute of Intelligent SensingZhejiang LabHangzhou 311100China Department of Biomedical Engineering The Chinese University of Hong KongHong KongChina

The topic of optical precise displacement measurement has garnered significant attention and generated widespread interest recently. The use of optical singularity offers a potential solution for this purpose, although effectively manipulating the singularity in an ideal manner remains challenging. In this work, we propose a theoretical approach to achieve controllable position modulation of the c-point in the focal plane, whose spatial position can be easily modulated by adjusting the relative offset factor β and the offset angle α of an azimuthal polarization beam(APB), while the interval and orientation of the c-points can be flexibly regulated. Notably, the chiral polarization state undergoes a distinct reversal along the link-line connecting the two c-points, thereby providing a promising approach for accurate displacement sensing. To evaluate its sensing characteristics, the varying pattern of the scattered field intensity is monitored when sweeping a gold helix and nanoparticle along the link-line. The results of simulation quality index Q verify that the equilibrium factor of the scattering field possesses an obvious linear relationship with the displacement, signifying a precise sub-nanometric *** research introduces new methods for the flexible control of polarization singularities in tightly focused fields,thereby enhancing the utilization of circular polarization properties near c-points for displacement *** findings not only enrich the field of nanometer measurement technology but also pave the way for new avenues of research in this domain.

关键词： polarization displacement precise

Global Spherically Symmetric Solutions for a coupled compressible Navier–Stokes/Allen–cahn System

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Acta Mathematica Sinica,English Series 2024年第8期40卷 2037-2064页

作者： chang Ming SONG Jian Lin zhang yuan yuan WANG Department of Applied Mathematics School of Mathematics and Information ScienceZhongyuan University of TechnologyZhengzhou 450007P.R.China

In this paper,we consider the global spherically symmetric solutions for the initial boundary value problem of a coupled compressible Navier–Stokes/Allen–cahn system which describes the motion of two-phase viscous compressible *** prove the existence and uniqueness of global classical solution,weak solution and strong solution under the assumption of spherically symmetry condition for initial dataρ0 without vacuum state.

关键词： Diffuse interface model global solutions Navier-Stokes equations Allen-cahn equation spherically symmetry

Resource Allocation for cognitive Network Slicing in PD-ScMA System Based on Two-Way Deep Reinforcement Learning

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china communications 2024年第6期21卷 53-68页

作者： zhang Zhenyu zhang Yong yuan Siyu cheng Zhenjie School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Key Laboratory of Work Safety Intelligent Monitoring(Beijing University of Posts and Telecommunications) Beijing 100876China

In this paper,we propose the Two-way Deep Reinforcement Learning(DRL)-Based resource allocation algorithm,which solves the problem of resource allocation in the cognitive downlink network based on the underlay *** users(SUs)in the cognitive network are multiplexed by a new Power Domain Sparse code Multiple Access(PD-ScMA)scheme,and the physical resources of the cognitive base station are virtualized into two types of slices:enhanced mobile broadband(eMBB)slice and ultrareliable low latency communication(URLLc)*** design the Double Deep Q Network(DDQN)network output the optimal codebook assignment scheme and simultaneously use the Deep Deterministic Policy Gradient(DDPG)network output the optimal power allocation *** objective is to jointly optimize the spectral efficiency of the system and the Quality of Service(QoS)of *** results show that the proposed algorithm outperforms the cNDDQN algorithm and modified JEERA algorithm in terms of spectral efficiency and QoS ***,compared with the Power Domain Non-orthogonal Multiple Access(PD-NOMA)slices and the Sparse code Multiple Access(ScMA)slices,the PD-ScMA slices can dramatically enhance spectral efficiency and increase the number of accessible users.

关键词： cognitive radio deep reinforcement learning network slicing power-domain non-orthogonal multiple access resource allocation

Benthodytes occidentpalauta ***.,a new species of deep-sea holothuroid(Elasipodida:Psychropotidae)from the west of Kyushu-Palau Ridge in the Western Pacific Ocean

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Journal of Oceanology and Limnology 2024年第1期42卷 252-262页

作者： chongzhen yuan chunsheng WANG Dongsheng zhang Key Laboratory of Marine Ecosystem Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China School of Oceanography Shanghai Jiao Tong UniversityShanghai 200030China

Benthodytes occidentpalauta *** collected from the Kyushu-Palau Ridge at a depth of 5481 m in *** new species is characterized by a gelatinous body wall,violet skin,six pairs of dorsal papillae,and a rough mid-ventral surface without tube *** dorsal deposits are rod-shaped and *** types of papillae deposits as crosses with four arms with central bipartite *** deposits are *** ossicles are rod-shaped with end *** deposits are rodshaped,tripartite,and *** phylogenetic analyses based on cytochrome oxidase subunit 1(cOI)and 16S individually and a concatenated dataset of cOI and 16S genes of this species support that *** *** to Benthodytes.

关键词： Holothuroidea Benthodytes cytochrome oxidase subunit 1(cOI) 16S phylogenetic analysis

Application of system identification in a practical active noise control system

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control Theory and Technology 2024年第2期22卷 282-291页

作者： Yu yuan Zhaoyang Sun Hongwei zhang School of Mechanical Engineering Xihua UniversityChengdu610039SichuanChina School of Electrical Engineering Southwest Jiaotong UniversityChengdu611756SichuanChina School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhen518055GuangdongChina

Noise pollution has become increasingly severe around the world due to fast urbanization. How to soundproof windows from outside noise is of significant interest for both academia and industry. This paper reports an experimental implementation of normalized minmax active noise control (ANc) algorithm on an open window system, where identifying the model of acoustic sound paths plays a central role. By doing this, traffic noise is attenuated by the ANc system, leading to a relatively quiet indoor environment, while the natural lighting and ventilation functions of a window are remained. Our experiments show that an average of 19 dB(A) noise reduction is achieved.

关键词： Active noise control Multi-input-multi-output system Normalized minimax algorithm System identification

Influence of calendering process on the structural mechanics and heat transfer characteristics of lithium-ion battery electrodes via DEM simulations

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Particuology 2024年第2期85卷 252-267页

作者： Junpeng zhang Jingna Sun Huagui Huang Zhenge yuan National Engineering Research center for Equipment and Technology of cold Strip Rolling Yanshan UniversityQinhuangdao066004China Xingtai Naknor Technology co. LtdXingtai054000China

Elucidating the intricate correlation between calendering,structure,and performance is crucial to comprehending the relationship between performance parameters and process steps of lithium-ion batteries(LIBs).Discrete element method(DEM)simulations were adopted in this work to calculate the interparticle force and stress tensor under incremental calendering process conditions,which revealed the effect of the anisotropy of complex contact force network on the anisotropy of heat transfer within porous *** thermal conductivity of electrode was predicted using porosity to characterize the process-structure-performance *** comprehensive influence of contact number and con-tact area between particles and current collector determines the magnitude of interfacial thermal resistance and interfacial heat transfer *** the first time,this work quantitatively analyzed the structural mechanics and heat transfer mechanism during calendering process of porous electrodes,and the results indicate a promising way to optimize and design battery electrode structures.

关键词： Li-ion battery electrode Structural mechanicsAnisotropy Thermal conductivity Discrete element method