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Scenario Modeling-Aided AP Placement Optimization Method for Indoor Localization and Network Access

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China Communications 2024年第3期21卷 37-50页

Owing to the ubiquity of wireless networks and the popularity of WiFi infrastructures,received signal strength(RSS)-based indoor localization systems have received much attention.The placement of access points(APs)significantly influences localization accuracy and network access.However,the indoor scenario and network access are not fully considered in previous AP placement optimization methods.This study proposes a practical scenario modelingaided AP placement optimization method for improving localization accuracy and network access.In order to reduce the gap between simulation-based and field measurement-based AP placement optimization methods,we introduce an indoor scenario modeling and Gaussian process-based RSS prediction method.After that,the localization and network access metrics are implemented in the multiple objective particle swarm optimization(MOPSO)solution,Pareto front criterion and virtual repulsion force are applied to determine the optimal AP placement.Finally,field experiments demonstrate the effectiveness of the proposed indoor scenario modeling method and RSS prediction model.A thorough comparison confirms the localization and network access improvement attributed to the proposed anchor placement method.

关键词： indoor localization MOPSO network access RSS prediction

Strain engineering of Pt-based electrocatalysts for oxygen reaction reduction

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Frontiers in Energy 2024年第2期18卷 241-262页

作者： Zeyu WANG Yanru liu Shun CHEN Yun ZHENG xiaogang FU Yan ZHANG Wanglei WANG State Key Laboratory of Solidification Processing Atomic Control and Catalysis Engineering LaboratorySchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration National Clinical Research Center for Oral DiseasesShaanxi Key Laboratory of StomatologyDepartment of Dental MaterialsSchool of StomatologyThe Fourth Military Medical UniversityXi’an 710032China Institute of New Energy Materials and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China Key Laboratory of Marine Chemistry Theory and Technology(Ministry of Education) College of Chemistry and Chemical EngineeringOcean University of ChinaQingdao 266100China

Proton exchange membrane fuel cells(PEMFCs)are playing irreplaceable roles in the construction of the future sustainable energy system.However,the insufficient performance of platinum(Pt)-based electrocatalysts for oxygen reduction reaction(ORR)hinders the overall efficiency of PEMFCs.Engineering the surface strain of catalysts is considered an effective way to tune their electronic structures and therefore optimize catalytic behavior.In this paper,insights into strain engineering for improving Pt-based catalysts toward ORR are elaborated in detail.First,recent advances in understanding the strain effects on ORR catalysts are comprehensively discussed.Then,strain engineering methodologies for adjusting Ptbased catalysts are comprehensively discussed.Finally,further information on the various challenges and potential prospects for strain modulation of Pt-based catalysts is provided.

关键词： strain engineering Pt-based catalysts oxygen reduction reaction(ORR) catalytic performance proton exchange membrane fuel cells(PEMFCs)

Stress-assisted corrosion mechanism of 3Ni steel by using gradient boosting decision tree machining learning method

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1311-1321页

作者： Xiaojia Yang Jinghuan Jia Qing Li Renzheng Zhu Jike Yang Zhiyong liu Xuequn Cheng xiaogang Li Institute of Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China AECC Key Laboratory of Advanced Corrosion and Protection of Aeronautical Materials AECC Beijing Institute of Aeronautical MaterialsBeijing 100095China Shunde Innovation School University of Science and Technology BeijingFoshan 528399China

Traditional 3Ni weathering steel cannot completely meet the requirements for offshore engineering development,resulting in the design of novel 3Ni steel with the addition of microalloy elements such as Mn or Nb for strength enhancement becoming a trend.The stress-assisted corrosion behavior of a novel designed high-strength 3Ni steel was investigated in the current study using the corrosion big data method.The information on the corrosion process was recorded using the galvanic corrosion current monitoring method.The gradi-ent boosting decision tree(GBDT)machine learning method was used to mine the corrosion mechanism,and the importance of the struc-ture factor was investigated.Field exposure tests were conducted to verify the calculated results using the GBDT method.Results indic-ated that the GBDT method can be effectively used to study the influence of structural factors on the corrosion process of 3Ni steel.Dif-ferent mechanisms for the addition of Mn and Cu to the stress-assisted corrosion of 3Ni steel suggested that Mn and Cu have no obvious effect on the corrosion rate of non-stressed 3Ni steel during the early stage of corrosion.When the corrosion reached a stable state,the in-crease in Mn element content increased the corrosion rate of 3Ni steel,while Cu reduced this rate.In the presence of stress,the increase in Mn element content and Cu addition can inhibit the corrosion process.The corrosion law of outdoor-exposed 3Ni steel is consistent with the law based on corrosion big data technology,verifying the reliability of the big data evaluation method and data prediction model selection.

关键词： weathering steel stress-assisted corrosion gradient boosting decision tree machining learning

Simulation of gas-solids heat transfer in cyclone pyrolyzer using CFD-DEM model

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Particuology 2024年第2期85卷 155-166页

作者： Nan Zhang Xueer Pan Jingxuan Yang Qian liu Wenhao Lian Xiao Du Zhonglin Zhang xiaogang Hao Guoqing Guan College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan030024China School of Chemistry and Chemical Engineering North University of ChinaTaiyuan030051China Shanxi Jinke Technology Service Company Limited Taiyuan030000China Labraory of Eey onveron Engineerng Institute f Rgional Innvation(RI)Hosaki Univerty3-BunkychoHiroak036-8561Japan

Fast heat transfer in the pyrolyzer can increase the yield of pyrolysis gas and tar,and improve the quality of tar.Compared with the downer pyrolyzer,the cyclone pyrolyzer can simultaneously achieve high solids holdup and violent turbulence,and correspondingly faster heat transfer.In this work,the heat transfer behavior in the cyclone pyrolyzer is specifically studied using the computational fluid dynamics-discrete element method.The simulation results reveal that the gas-solids heat convection contributes mainly to the heat transfer process,and the heat radiation and conduction are relatively small and almost negligible,respectively.Compared with the downer pyrolyzer under the same operating conditions,the heating rate is significantly increased in the cyclone pyrolyzer.By analyzing the flow characteristics in the cyclone pyrolyzer,it is found that the region of high convective heat transfer rate coincides with that of natural cyclone length.Additionally,the final coal temperature increases with the increase of gas velocity and exists a maximum value.These results can offer some qualitative understanding of the heat transfer behavior in the cyclone pyrolyzer.

关键词： Cyclone pyrolyzer Rapidly heating Heat convection Natural cyclone length CFD-DEM

Enhancing multifunctional photocatalysis with acetate-assisted cesium doping and unlocking the potential of Z-scheme solar water splitting

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Carbon Energy 2024年第3期6卷 178-195页

作者： Mengmeng Ma Jingzhen Li xiaogang Zhu Kong liu Kaige Huang Guodong Yuan Shizhong Yue Zhijie Wang Shengchun Qu Key Laboratory of Semiconductor Materials Science Beijing Key Laboratory of Low Dimensional Semiconductor Materials and DevicesInstitute of SemiconductorsChinese Academy of SciencesBeijingChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina Department of Physics College of Physical Science and TechnologyXiamen UniversityXiamenChina State Key Laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijingChina

Graphitic carbon nitride(g-C_(3)N_(4))has been extensively doped with alkali metals to enlarge photocatalytic output,in which cesium(Cs)doping is predicted to be the most efficient.Nevertheless,the sluggish diffusion and doping kinetics of precursors with high melting points,along with imprecise regulation,have raised the debate on whether Cs doping could make sense.For this matter,we attempt to confirm the positive effects of Cs doping on multifunctional photocatalysis by first using cesium acetate with the character of easy manipulation.The optimized Csdoped g-C_(3)N_(4)(CCN)shows a 41.6-fold increase in visible-light-driven hydrogen evolution reaction(HER)compared to pure g-C_(3)N_(4) and impressive degradation capability,especially with 77%refractory tetracycline and almost 100%rhodamine B degradedwithin an hour.The penetration ofCs+is demonstrated to be a mode of interlayer doping,and Cs–N bonds(especially with sp^(2) pyridine N in C═N–C),along with robust chemical interaction and electron exchange,are fabricated.This atomic configuration triggers the broadened spectral response,the improved charge migration,and the activated photocatalytic capacity.Furthermore,we evaluate the CCN/cadmium sulfide hybrid as a Z-scheme configuration,promoting the visible HER yield to 9.02 mmol g^(−1) h^(−1),which is the highest ever reported among all CCN systems.This work adds to the rapidly expanding field of manipulation strategies and supports further development of mediating served for photocatalysis.

关键词： acetate-assisted cesium doping multifunctional photocatalysis Z-scheme

Mastering lanthanide energy states for next-gen photonic innovation

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中国科学:化学英文版 2023年第9期66卷 2460-2479页

作者： Yuyang Gu Chang Gu Yuxiang Zhang Zhen Mu xiaogang liu Department of Chemistry National University of SingaporeSingapore 117543Singapore Institute of Materials Research and Engineering Agency for ScienceTechnology and ResearchSingapore 138634Singapore

Lanthanide-based photonic materials have been extensively explored for use in laser crystals,lighting,fiber-optic communications,bioimaging,diagnostics,and many other fields.In recent years,they have enabled numerous breakthroughs in areas such as single-particle spectroscopy,super-resolution imaging,micro-lasing,lifetime multiplexing,and detection.Here,we summarize recent advances in lanthanide photonic materials from an energy state perspective,focusing on the interplay between energy state manipulation and advanced photonic applications.We then discuss the challenges and prospects for controlling energy states at the single-particle level.We wish to highlight the importance of quantifying and understanding the energy states of lanthanides for future innovations.

关键词： lanthanide nanomaterials super-resolution lifetime lasing

A TICS-fluorophore based probe for dual-color GSH imaging

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Chinese Chemical Letters 2022年第11期33卷 4943-4947页

作者： Wenjuan liu Jie Chen Qinglong Qiao xiaogang liu Zhaochao Xu CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China Fluorescence Research Group Singapore University of Technology and DesignSingapore 487372Singapore

Cascading reactions in fluorophores accompanied by the replacement of different fluorescence wavelengths can be used to develop luminescent materials and reactive fluorescent probes.Based on multiple signal channels,the selectivity of probes can be improved and the range of response to guest molecule recognition can be expanded.By regulating the position,number,and activity of active sites in fluorophores,fluorescent probes that successively react with thiol and amino groups in cysteine(Cys),homocysteine(Hcy)have been developed,which can only react with the thiol group of GSH,In this paper,we report the first probe capable of cascading nucleophilic substitution reaction with the thiol group and amino group of GSH at a single reaction site,and showed the dual-color recognition of GSH,which improved the selectivity of GSH also was an extension of GSH probes.The probe Rho-DEA was based on a TICS fluorophore,and the intramolecular cascade nucleophilic substitution reaction occurs with Cys/Hcy.The thiol substitution of the first step reaction with Cys/Hcy was quenched due to intersystem crossing to triplet state,so GSH can be selectively recognized from the fluorescence signal.Rho-DEA has the ability of mitochondrial localization,and finally realized in situ dual-color fluorescence recognition of GSH in mitochondria.

关键词： TICS Reactive fluorescent probe GSH imaging Dual-color Cascading reaction

Jiaohong pills attenuate neuroinflammation and amyloid-βprotein-induced cognitive deficits by modulating the mitogen-activated protein kinase/nuclear factor kappa-B pathway

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Animal Models and Experimental Medicine 2024年第3期7卷 222-233页

作者： Hong Zhang Weiyan Cai Lijinchuan Dong Qing Yang Qi Li Qingsen Ran Li liu Yajie Wang Yujie Li xiaogang Weng Xiaoxin Zhu Ying Chen Institute of Chinese Materia Medica China Academy of Chinese Medical SciencesBeijingChina

Background:Jiaohong pills(JHP)consist of Pericarpium Zanthoxyli(PZ)and Radix Rehmanniae,two herbs that have been extensively investigated over many years due to their potential protective effects against cognitive decline and memory impairment.However,the precise mechanisms underlying the beneficial effects remain elusive.Here,research studies were conducted to investigate and validate the therapeutic effects of JHP on Alzheimer's disease.Methods:BV-2 cell inflammation was induced by lipopolysaccharide.AD mice were administered amyloid-β(Aβ).Behavioral experiments were used to evaluate learning and memory ability.The levels of nitric oxide(NO),tumor necrosis factor-alpha(TNF-α),interleukin-1β(IL-1β),and interleukin-10(IL-10)were detected using enzymelinked immunosorbent assay(ELISA).The protein expressions of inducible nitric oxide synthase(iNOS)and the phosphorylation level of mitogen-activated protein kinase(MAPK)and nuclear factor kappa-B(NF-κB)were detected using Western blot.Nissl staining was used to detect neuronal degeneration.Results:The results demonstrated that an alcoholic extract of PZ significantly decreased the levels of NO,IL-1β,TNF-α,and iNOS;increased the expression level of IL-10;and significantly decreased the phosphorylation levels of MAPK and NF-κB.These inhibitory effects were further confirmed in the AD mouse model.Meanwhile,JHP improved learning and memory function in AD mice,reduced neuronal damage,and enriched the Nissl bodies in the hippocampus.Moreover,IL-1βand TNF-αin the cortex were significantly downregulated after JHP administration,whereas IL-10showed increased expression.Conclusions:It was found that JHP reduced neuroinflammatory response in AD mice by targeting the MAPK/NF-κB signaling pathway.

关键词： amyloid-β(Aβ)protein BV2 neuroinflammation Pericarpium Zanthoxyli Radix Rehmanniae

Outcomes of patients awaiting lung transplantation after the implementation of donation after brain death at a single Chinese center

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Frontiers of Medicine 2022年第5期16卷 760-765页

作者： Yuling Yang Xinnan Xu Ming liu Yanfeng Zhao Yongmei Yu xiaogang liu Chang Chen Gening Jiang Wenxin He Department of Thoracic Surgery Shanghai Pulmonary HospitalSchool of MedicineTongji UniversityShanghai 200092China Department of Cardiothoracic Surgery Zhangzhou Affiliated Hospital of Fujian Medical UniversityZhangzhou 363000China

oluntary contribution has become the only source of donor lungs in China since 2015.To elaborate the outcomes of patients awaiting lung transplantation(LTx)after the implementation of donation after brain death,we performed a retrospective study that encompassed 205 patients with end-stage lung disease who registered for LTx at Shanghai Pulmonary Hospital from January 1,2015 to January 1,2021.A total of 180 patients were enrolled in the study.The median waiting time was 1.25 months.Interstitial lung disease(ILD)(103/180,57.2%)and chronic obstructive pulmonary disease(COPD)(56/180,31.1%)were the most common diseases in our study population.The mean pulmonary artery pressure(mPAP)of patients in the died-waiting group was higher than that of the survivors(53.29+21.71 mmHg vs.42.11+18.58 mmHg,P-0.002).The mortality of patients with ILD(34/103,33.00%)was nearly twice that of patients with COPD(10/56,17.86%)while awaiting LTx(P-0.041).In the died-waiting group,patients with ILD had a shorter median waiting time than patients with COPD after being listed(0.865 months vs.4.720 months,P-0.030).ILD as primary disease and mPAP>35 mmHg were two significant independent risk factors for waitlist mortality,with hazard ratios(HR)of 3.483(95%CI 1.311-9.111;P-0.011)and 3.500(95%CI 1.435-8.536;P=0.006).Hence,LTx is more urgently needed in patients with ILD and pulmonary hypertension.

关键词： lung transplantation donation after brain death waitlist