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Analyzing the spatiotemporal evolution and driving forces of gross ecosystem product in the upper reaches of the Chaobai River Basin

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Frontiers of Environmental Science & Engineering 2024年第8期18卷 117-132页

作者： Jiacheng li Qi Han liqiu Zhang li feng Guihuan liu Beijing Key Laboratory for Source Control Technology of Water Pollution College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China Engineering Research Center for Water Pollution Source Control&Eco-remediation College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China Center of Eco-compensation Chinese Academy of Environmental PlanningMinistry of Ecology of EnvironmentBeijing 100041China

The Chaobai River Basin,which is a crucial ecological barrier and primary water source area within the Beijing-Tianjin-Hebei region,possesses substantial ecological *** gross ecosystem product(GEP)in the Chaobai River Basin is a reflection of ecosystem conditions and quantifies nature’s contributions to humanity,which provides a basis for basin ecosystem service management and *** study investigated the spatiotemporal evolution of GEP in the upper Chaobai River Basin and explored the driving factors influencing GEP spatial *** patterns from 2005 to 2020 were analyzed,and GEP was calculated for 2005,2010,2015,and *** driving factors influencing GEP spatial differentiation were identified using the optimal parameter-based geographical detector(OPGD)*** key findings are as follows:(1)From 2005 to 2020,the main ecosystem types were forest,grassland,and *** areas experienced significant changes,and conversions mainly occurred among urban,water,grassland and agricultural ecosystems.(2)Temporally,the GEP in the basin increased from 2005 to 2020,with regulation services *** the county(district)scale,GEP exhibited a north-west-high and south-east-low pattern,showing spatial differences between per-unit-area GEP and county(district)GEP,while the spatial variations in per capita GEP and county(district)GEP were similar.(3)Differences in the spatial distribution of GEP were influenced by regional natural geographical and socioeconomic *** these factors,gross domestic product,population density,and land-use degree density contributed *** among different driving forces noticeably impacted GEP spatial *** findings underscore the necessity of incorporating factors such as population density and the intensity of land-use development into ecosystem management decision-making processes in the upper reaches of the Chaobai River *** policies

关键词： Ecosystem pattern Gross ecosystem product(GEP) Spatiotemporal evolution Optimal parameter-based geographical detector(OPGD) Chaobai River Basin

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Built-in electric field induced S-scheme g-C_(3)N_(4)homojunction for efficient photocatalytic hydrogen evolution:Interfacial engineering and morphology control

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Nano Research 2024年第6期17卷 4961-4970页

作者： Yongpan Gu Yike li Haoqiang feng Yanan Han Zhongjun li College of Chemistry Zhengzhou UniversityZhengzhou 450001China

S-scheme possesses superior redox capabilities compared with the II-scheme,providing an effective method to solve the innate defects of g-C_(3)N_(4)(CN).In this study,S-doped g-C_(3)N_(4)/g-C_(3)N_(4)(SCN-tm/CN)S-scheme homojunction was constructed by rationally integrating morphology control with interfacial engineering to enhance the photocatalytic hydrogen evolution ***-situ Kelvin probe force microscopy(KPFM)confirms the transport of photo-generated electrons from CN to *** functional theory(DFT)calculations reveal that the generation of a built-in electric field between SCN and CN enables the carrier separation to be more efficient and *** transient absorption spectrum(fs-TAS)indicates prolonged lifetimes of SCN-tm/CN_(3)(τ1:9.7,τ2:110,andτ3:1343.5 ps)in comparison to those of CN(τ1:4.86,τ2:55.2,andτ3:927 ps),signifying that the construction of homojunction promotes the separation and transport of electron hole pairs,thus favoring the photocatalytic *** visible light irradiation,the optimized SCN-tm/CN_(3)exhibits excellent photocatalytic activity with the hydrogen evolution rate of 5407.3μmol·g^(−1)·h^(−1),which is 20.4 times higher than that of CN(265.7μmol·g^(−1)·h^(−1)).Moreover,the homojunction also displays an apparent quantum efficiency of 26.8%at 435 nm as well as ultra-long and ultra-stable cycle *** work offers a new strategy to construct highly efficient photocatalysts based on the metal-free conjugated polymeric CN for realizing solar energy conversion.

关键词： homojunction built-in electric field morphology control interfacial engineering carrier separation

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Estimation of Hammerstein nonlinear systems with noises using filtering and recursive approaches for industrial control

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 260-271页

作者： Mingguang ZHANG feng li Yang YU Qingfeng CAO School of Electrical&Information Engineering Jiangsu University of TechnologyChangzhou213001China College of Electrical Energy and Power EngineeringYangzhou UniversityYangzhou225127China

This paper discusses a strategy for estimating Hammerstein nonlinear systems in the presence of measurement noises for industrial control by applying filtering and recursive *** proposed Hammerstein nonlinear systems are made up of a neural fuzzy network(NFN)and a linear state`-space *** estimation of parameters for Hammerstein systems can be achieved by employing hybrid signals,which consist of step signals and random ***,based on the characteristic that step signals do not excite static nonlinear systems,that is,the intermediate variable of the Hammerstein system is a step signal with different amplitudes from the input,the unknown intermediate variables can be replaced by inputs,solving the problem of unmeasurable intermediate variable *** the presence of step signals,the parameters of the state-space model are estimated using the recursive extended least squares(RELS)***,to effectively deal with the interference of measurement noises,a data filtering technique is introduced,and the filtering-based RELS is formulated for estimating the NFN by employing random ***,according to the structure of the Hammerstein system,the control system is designed by eliminating the nonlinear block so that the generated system is approximately equivalent to a linear system,and it can then be easily controlled by applying a linear *** effectiveness and feasibility of the developed identification and control strategy are demonstrated using two industrial simulation cases.

关键词： Hammerstein nonlinear systems Neural fuzzy network Data filtering Hybrid signals Industrial control

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Evaluation of transmission risk of respiratory particles under different ventilation strategies in an elevator

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Building Simulation 2024年第5期17卷 771-784页

作者： liangyu Zhu Xian li Bujin feng Fan liu School of Civil Engineering and Architecture Linyi UniversityLinyi276000China College of Agriculture Shandong Agricultural UniversityTaian271018China School of Environment and Architecture University of Shanghai for Science and TechnologyShanghai200093China

People in elevators are at risk of respiratory infection because the elevator cabin is crowded and has poor *** exhaled particles may be inhaled by the susceptible person,deposited on the surface and suspended in the elevator,which can result in direct and indirect ***,whether the air vent designs adopted in the elevator can effectively reduce the transmission risk of respiratory particles remains *** this study,the dispersion of particles under four common ventilation strategies used in the commercial elevator was investigated by proven computational fluid dynamics(CFD)*** flow field was simulated with the RNG κ-ξ turbulence model and the Lagrangian method was adopted to track particle *** effects of air vent layout and airflow rate on particle transmission were *** found that more than 50% of exhaled particles(average value)were suspended in the cabin and difficult to discharge under the investigated ventilation *** deposited fraction of particles on the susceptible person reached up to 39.14% for infiltration ventilation,which led to a high risk of contact *** the ventilation rate could not significantly reduce the inhalation proportion of particles due to the poor airflow distribution inside the elevator.A more proper ventilation strategy should be explored for the elevator to control transmission risk.

关键词： particle dispersion transmission risk elevator ventilation strategy computational fluid dynamics(CFD)

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Classification and spectrum optimization method of grease based on infrared spectrum

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Friction 2024年第6期12卷 1154-1164页

作者： Xin feng Yanqiu XIA Peiyuan XIE Xiaohe li School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing 102206China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

The infrared(IR)absorption spectral data of 63 kinds of lubricating greases containing six different types of thickeners were obtained using the IR *** Kohonen neural network algorithm was used to identify the type of the lubricating *** results show that this machine learning method can effectively eliminate the interference fringes in the IR spectrum,and complete the feature selection and dimensionality reduction of the high-dimensional spectral *** 63 kinds of greases exhibit spatial clustering under certain IR spectrum recognition spectral bands,which are linked to characteristic peaks of lubricating greases and improve the recognition accuracy of these *** model achieved recognition accuracy of 100.00%,96.08%,94.87%,100.00%,and 87.50%for polyurea grease,calcium sulfonate composite grease,aluminum(Al)-based grease,bentonite grease,and lithium-based grease,*** on the different IR absorption spectrum bands produced by each kind of lubricating grease,the three-dimensional spatial distribution map of the lubricating grease drawn also verifies the accuracy of classification while recognizing the *** paper demonstrates fast recognition speed and high accuracy,proving that the Kohonen neural network algorithm has an efficient recognition ability for identifying the types of the lubricating grease.

关键词： grease infrared(IR)spectroscopy layered Kohonen network species recognition spectrum band optimization

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Compositionally graded high-voltage P2-type cathode with superior structural stability and redox kinetics for advanced Na-ion batteries

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Nano Research 2024年第4期17卷 2755-2762页

作者： Peiyu Hou Mohan Dong Zhenbo Sun feng li School of Physics and Technology University of JinanJinan 250022China

Layered P2-type cathodes with high voltage,large capacity,and easy synthesis show great potential for developing sodium(Na)-ion batteries(NIBs).However,the P2–O2 phase transition makes their structural degradation and the Na^(+)/vacancy ordering lowers their redox ***,we rationally propose a compositionally graded P2-type cathode,where nickel(Ni)and manganese(Mn)fractions decrease gradually,and cobalt(Co)content increases contiguously from the inside to the outside of a secondary *** these particles,the Ni/Mn-based compound delivers high capacity and high *** the surface of particles,the Co/Mn-based solid solution offers a stable buffer *** from these synergistic effects,this graded P2-type cathode shows the elimination of P2–O2 transformation even when charged to 4.4 V,which enables good structural stability,maintaining capacity retention reaching~80%within 300 ***,the Na^(+)/vacancy ordering superstructure is further suppressed,and the Na^(+)diffusion kinetics is significantly *** proposed graded structure with optimized chemical composition offers a new perspective for eliminating the unwanted phase transition and thus enhancing the electrochemistry of high-voltage layered cathodes for advanced NIBs.

关键词： Na-ion battery P2-type cathode composition regulation phase transition redox stability

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Galectin 2 regulates JAK/STAT3 signaling activity to modulate oral squamous cell carcinoma proliferation and migration in vitro

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BIOCELL 2024年第5期48卷 793-801页

作者： XINRU feng li XIAO Medical School University of Electronic Science and Technology of ChinaChengdu610072China Department of Stomatology Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengdu610072China

Background:Galectin 2(LGALS2)is a protein previously reported to serve as a mediator of disease progression in a range of *** function of LGALS2 in oral squamous cell carcinoma(OSCC),however,has yet to be explored,prompting the present study to address this literature ***:Overall,144 paired malignant tumor tissues and paracancerous OSCC patient samples were harvested and the LGALS2 expression levels were examined through qPCR and western *** LGALS2 coding sequence was introduced into the pcDNA3.0 vector,to enable the overexpression of this gene,while an LGALS2-specific shRNA and corresponding controls were also *** functionality of LGALS2 as a regulator of the ability of OSCC cells to grow and undergo apoptotic death in vitro was assessed through EdU uptake and CCK-8 assays,and flow cytometer,whereas a Transwell system was used to assess migratory activity and *** agonist of the Janus Kinase 2(JAK2)/Signal Transducer and Activator of Transcription 3(STAT3)pathway was also used to assess the role of this pathway in the context of LGALS2 ***:Here,we found that lower LGALS2 protein and mRNA expression were evident in OSCC tumor tissue samples,and these expression levels were associated with clinicopathological characteristics and patient survival *** LGALS2 enhanced proliferation in OSCC cells while rendering these cells better able to resist *** opposite was instead observed after LGALS2 was ***,the ability of LGALS2 to suppress the progression of OSCC was related to its ability to activate the JAK/STAT3 signaling ***:Those results suggest a role for LGALS2 as a suppressor of OSCC progression through its ability to modulate JAK/STAT3 signaling,supporting the potential utility of LGALS2 as a target for efforts aimed at treating OSCC patients.

关键词： LGALS2 Oral squamous cell carcinoma(OSCC) Janus Kinase 2/Signal Transducer and Activator of Transcription 3(JAK2-STAT3) Progression

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Effect of oxide inclusions on MnS precipitates and tensile mechanical property of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第5期31卷 1210-1220页

作者： Xiao-yong Gao Hong Wei li-feng Zhang School of Mechanical Engineering Yanshan UniversityQinhuangdao066004HebeiChina School of Materials Science and Engineering Yanshan UniversityQinhuangdao066004HebeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing100144China

The key role of oxide inclusions on the microstructure and mechanical property of a high-strength low-alloy steel was *** field emission scanning electron microscope equipped with energy-dispersive spectrometry was used to characterize MnS *** inclusions play an important role in the shape control of MnS *** oxides fovored to decrease the size and the aspect ratio of MnS *** less oxide inclusions in the steel,approximately over 16.7%MnS precipitates were with aspect ratio a>5 and pure MnS precipitates accounted for 75.9%in ***,with more oxide inclusions in the steel,only 7.4%MnS precipitates were with a>5 and pure MnS precipitates accounted for 60.1%in *** of MnS by oxide inclusions improved the strength and inhibited the *** oxide inclusions in the steel increased the yield strength and tensile strength of the steel in both longitudinal and transverse directions,and lowered the anisotropy of the mechanical property.

关键词： High-strength low-alloy steel MnS Oxide inclusion Mechanical property Anisotropy

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Polycrystalline ZSM-5 Aggregates Induced by Seed and Catalytic Performance in Methanol to Hydrocarbon

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无机材料学报 2024年第8期39卷 945-954,I0010-I0013页

作者： WANG Xuchang jiao Chuyu JI Zhuo jiao Qirui QIN Bo DU Yanze ZHENG Jiajun li Ruifeng Key Laboratory of Coal Science and Technology MOE Research Centre of Energy Chemical&Catalytic TechnologyTaiyuan University of TechnologyTaiyuan 030024China SINOPEC Dalian Research Institute of Petroleum and Petrochemicals Co. Ltd.SINOPECDalian 116045China

Synthesis of ZSM-5 zeolite typically utilizes small molecule polyamines or quaternary ammonium salts as organic structure guiding agent(OSDA).By contrast,the OSDA-free hydrothermal synthesis system eliminates the use of organic templates and the subsequent calcination *** not only reduces the cost of synthesis,but also prevents environmental pollution from the combustion of organic templates,representing an eco-friendly *** this,literature suggests that even so-called template-free synthesis systems often involve trace amount of organic substances like *** the present work,a calcined commercial ZSM-5 zeolite was served as seed,with sodium aluminate as aluminum source and silica sol as silicon source,ensuring an entirely template-free synthesis *** ZSM-5 aggregates consisted of rod-like nanocrystals were successfully prepared in the completely OSDA-free *** of the Si/Al ratio in ZSM-5 seed,dosage and crystallization conditions such as crystallization temperature and crystallization time on ZSM-5 synthesis were *** results show that a highly crystallinity ZSM-5 aggregate consisting of primary nano-sized crystals less than 100 nm is produced from a gel precursor with 5.6%(in mass)seed after hydrothermal treatment for 48 ***,the Si/Al ratio in ZSM-5 seed has little effect on the topological structure and pore structure of the synthesized ***,the seeds with a low Si/Al ratio facilitate faster crystallization of zeolite and enhance the acidity,especially the strong acid centers,of the *** catalytic performance of the synthesized polycrystalline ZSM-5 was evaluated during dehydration of methanol and compared with a commercial reference *** results exhibit that as compared with the reference catalyst,the fabricated sample has a longer catalytic lifetime(16 h vs 8 h)attributed to its hierarchical pores derived from the loosely packed primary ***

关键词： ZSM-5 polycrystalline aggregate crystal seed structure guiding agent

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Heteroepitaxial growth of Au@Pd core–shell nanocrystals with intrinsic chiral surfaces for enantiomeric recognition

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Rare Metals 2024年第1期43卷 225-235页

作者： feng-Xia Wu feng-Hua li Xia-li Lv Qi-Xian Zhang Guo-Bao Xu Wen-Xin Niu State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Shaoxing Institute of Technology Shanghai UniversityShaoxing 312000China University of Science and Technology of China Hefei 230026China School of Materials Science and Engineering Shanghai UniversityShanghai 200436China Zhejiang Institute of Advanced Materials Shanghai UniversityJiashan 314113China University of Chinese Academy of Sciences Beijing 100039China

Noble metal surfaces with intrinsic chirality serve as an ideal candidate for investigating enantioselective chemistry due to their superior chemical durability and high catalytic ***,significant advance has been made in synthesizing metal nanocrystals with intrinsic ***,the majority reports are limited to ***,through a heteroepitaxial growth strategy,the synthesis of metal nanocrystals with intrinsic chirality to palladium was extended for the first time and their application in enantioselective recognition was *** heteroepitaxial growth strategy allows for transferring the chirality of homochiral Au nanocrystals to Au@Pd core–shell *** employing the chiral Au@Pd nanocrystals as enantiomeric recognizing elements,a series of electrochemical sensors for chiral discrimination were *** optimal conditions,the peak potential between D-dihydroxyphenylalanine(D-DOPA)and L-dihydroxyphenylalanine(L-DOPA)is about 80 m V,and the peak current of D-DOPA is 2 times as much as that of L-DOPA,which enables the determination of the enantiomeric excess(EE,%)of ***,this report not only introduces a heteroepitaxial growth strategy to synthesize metal nanocrystals with intrinsic chirality,but also demonstrates the superior capability of integrating intrinsic chirality and catalytic properties into metal nanocrystals for chiral recognition.

关键词： Core–shell nanostructures Chirality transfer Electrochemical sensors Chiral recognition Chiroplasmonics

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