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Parameter Estimation of a Valve-Controlled Cylinder System Model Based on Bench Test and Operating Data Fusion

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 247-263页

作者： Deying su Shaojie wang Haojing Lin Xiaosong Xia Yubing Xu Liang Hou Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361102China Xuzhou XCMG Excavation Machinery Co. LtdXuzhou 221000China

The accurate estimation of parameters is the premise for establishing a high-fidelity simulation model of a valve-controlled cylinder *** test data are easily obtained,but it is challenging to emulate actual loads in the research on parameter estimation of valve-controlled cylinder *** the actual load information contained in the operating data of the control valve,its acquisition remains *** paper proposes a method that fuses bench test and operating data for parameter estimation to address the aforementioned *** proposed method is based on Bayesian theory,and its core is a pool fusion of prior information from bench test and operating ***,a system model is established,and the parameters in the model are ***,the bench and operating data of the system are ***,the model parameters and weight coefficients are estimated using the data fusion ***,the estimated effects of the data fusion method,Bayesian method,and particle swarm optimisation(PSO)algorithm on system model parameters are *** research shows that the weight coefficient represents the contribution of different prior information to the parameter estimation *** effect of parameter estimation based on the data fusion method is better than that of the Bayesian method and the PSO *** load complexity leads to a decrease in model accuracy,highlighting the crucial role of the data fusion method in parameter estimation studies.

关键词： Valve-controlled cylinder system Parameter estimation The Bayesian theory Data fusion method Weight coefficients

Boosting sodium-storage properties of hierarchical Na_(3)V_(2)(PO_(4))_(3)@C micro-flower cathodes by tiny Cr doping:The effect of“four ounces moving a thousand pounds”

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Nano Research 2024年第1期17卷 235-244页

作者： Yongjia wang Guoshuai su Xiaoying Li Linrui Hou Longwei Liang Changzhou Yuan School of Materials Science&Engineering University of JinanJinan 250022China

Na_(3)V_(2)(PO_(4))_(3)(NVP),as a great potential cathode candidate for Na-ion batteries(NIBs),has attracted enormous interest due to its three-dimensional(3D)large open framework for convenient Na+transport,yet its practical application is still limited by its inferior electron conductivity and sluggish Na+diffusion ***,the tiny Cr doped hierarchical NVP micro-flower cathodes(i.e.,Na_(3)V_(2-x)Crx(PO_(4))_(3)@C,x≤0.1),which are self-assembled with single-crystal nanoflake subunits in-situ coated with carbon nano-shell,are designed and fabricated via a scalable *** optimized cathode,i.e.,Na_(3)V_(1.94)Cr_(0.06)(PO_(4))_(3)@C(NVCP-6),was endowed with more electro-active Na(2)sites and higher electronic/ionic conductivity for efficient sodium *** from these competitive merits,the NVCP-6,when evaluated as a cathode towards NIBs,exhibits an ultrahigh-rate capability of 99.8 mAh·g^(-1)at 200 C and superior stability of 82.2%over 7300 cycles at 50 ***,the NVCP-6 based full NIBs display remarkable electrochemical properties in terms of both high-rate capacities and long-duration cycling properties at different temperatures(-20–50°C).The contribution,i.e.,the design of“four ounces can move a thousand pounds”,here will promote the practical industrial application of NVP towards advanced NIBs.

关键词： Na_(3)V_(2)(PO_(4))_(3)cathode tiny Cr doping active Na sites ultrahigh-rate capability Na-ion batteries

Thermodynamic phase transition and winding number for the third-order Lovelock black hole

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Chinese Physics C 2024年第9期48卷 188-198页

作者： Yu-Shan wang zhen-Ming Xu Bin Wu School of Physics Northwest UniversityXi'an 710127China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xi'an 710127China Peng Huanwu Center for Fundamental Theory Xi'an 710127China

Phase transition is important for understanding the nature and evolution of the black hole thermodynamic *** this study,we predicted the phase transition of the third-order Lovelock black hole using the winding numbers in complex analysis,and qualitatively validated this prediction by the generalized free *** the 7sult further deepens the research on black hole phase transitions using the complex analysis.

关键词： black hole thermodynamics Lovelock black hole phase transition

Seasonal and Genetic Characteristics of Human Metapneumovirus Circulating—Henan Province,China,2017-2023

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China CDC weekly 2024年第20期6卷 450-456,I0001页

作者： Zhibo Xie zhen Zhu Jin Xu Naiying Mao Aili Cui Wenhui wang Yage wang Zhibo Zhang Baicheng Xia Haoran wang zhen sun Yan Zhang National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases NHC Key Laboratory of Medical Virology and Viral DiseaseNational Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina Henan Provincial Center for Disease Control and Prevention Luohe CityHenan ProvinceChina Luohe Center for Disease Control and Prevention Luohe CityHenan ProvinceChina Luohe Central Hospital Luohe CityHenan ProvinceChina

Introduction:This study examines the seasonal and genetic characteristics of human metapneumovirus(HMPV)in Henan from 2017 to ***:Samples from patients with acute respiratory infection(ARI)testing positive for HMPV were subjected to real-time reverse transcription polymerase chain reaction The G gene was amplified and sequenced from these samples for epidemiological and phylogenetic ***:We enrolled 2,707 ARI patients from October 2017 to March 2023,finding an HMPV positivity rate of 6.17%(167/2,707).Children under five exhibited the highest infection rate at 7.78%(138/1,774).The 2018 and 2019 HMPV outbreaks predominantly occurred in spring(March to May),with peak positivity rates of 31.11%in May 2018 and 19.57%in May 2019.A notable increase occurred in November 2020,when positivity reached a historic high of 42.11%,continuing until January *** February 2021 through March 2023,no significant seasonal peaks were observed,with rates ranging from 0%to 8.70%.Out of 81 G gene sequences analyzed,46.91%(38/81)were identified as subtype A(A2c:45.67%,37/81;A2b:1.23%,1/81)and 53.09%(43/81)as subtype B(B1:9.88%,8/81;B2:43.21%,35/81).Notably,an AAABBA switch pattern was observed in HMPV *** dominant strains were A2c111nt-dup in subtype A and B2 in subtype ***:Six years of surveillance in Henan Province has detailed the seasonal and genetic dynamics of HMPV,contributing valuable insights for the control and prevention of HMPV infections in *** findings support the development of targeted HMPV vaccines and immunization strategies.

关键词： prevention finding seasonal

Effect of Y_(2)O_(3) on microstructure and properties of CoCrFeNiTiNb high entropy alloy coating on Ti-6Al-4V surface by laser cladding

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Journal of Rare Earths 2024年第3期42卷 586-599,I0006页

作者： zhen Li Wei Zhao Kedong Yu Ning Guo Guangchun Xiao Zhiming wang Hui Zhang College of Mechanical Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan250353China Shandong Institute of Mechanical Design and Research Jinan250031China

The effects of Y_(2)O_(3) on the microstructure, microhardness, wear resistance, high-temperature oxidation resistance, hot corrosion resistance, and electrochemical corrosion behaviour of CoCrFeNiTiNb high entropy alloy coatings formed on Ti-6Al-4V alloy surfaces were studied. The results show that the addition of Y_(2)O_(3) changes the proportion of the phase but does not change its type. The average grain size is only 1/4.7 of that of the high entropy alloy(HEA) coating, and the fine-grained strengthening leads to increases in the microhardness and wear resistance of 21.8% and 26.9%, respectively. The addition of Y_(2)O_(3) enhances the denseness and bonding properties of the oxide and corrosion product layers, reducing the oxidation and hot corrosion rates by 60.3% and 40.3%, respectively. The addition of Y_(2)O_(3) doubles the corrosion resistance which is attributed to the refinement of the grains, the increased proportion of HCP and TiN, and the weakening of galvanic coupling corrosion.

关键词： Laser cladding High entropy alloy coatings Rare earths Wear properties High temperature properties Electrochemical corrosion

Testing the first law of black hole mechanics with gravitational waves

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 76-82页

作者： Chao-Wan-zhen wang Jin-Bao Zhu Guo-Qing Huang Fu-Wen Shu Department of Physics Nanchang UniversityNanchang 330031China Center for Relativistic Astrophysics and High Energy Physics Nanchang UniversityNanchang 330031China GCAP-CASPER Physics DepartmentBaylor UniversityWaco 76798-7316USA

The successful observation of gravitational waves has provided humanity with an additional method to explore the universe,particularly black *** this study,we utilize data from LIGO and Virgo gravitational wave observations to test the first law of black hole mechanics,employing two different *** consider the secondary compact object as a perturbation to the primary black hole before the merger,and the remnant black hole as a stationary black hole after the *** the pre-merger and post-merger analysis,our results demonstrate consistency with the first law,with an error level of approximate 25%at a68%credibility level for *** the full inspiral-merger-ringdown analysis,our results show consistency with the first law of black hole mechanics,with an error level of about 6%at a 68%credibility level and 10%at a 95%credibility level for ***,we observe that the higher the mass ratio of the gravitational wave source,the more consistent our results are with the first law of black hole ***,our study sheds light on the nature of compact binary coalescence and their implications for black hole mechanics.

关键词： gravitational waves black hole mechanics data analysis ringdown

Advanced 3D ordered electrodes for PEMFC applications: From structural features and fabrication methods to the controllable design of catalyst layers

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Green Energy & Environment 2024年第9期9卷 1336-1365页

作者： Kaili wang Tingting Zhou zhen Cao Zhimin Yuan Hongyan He Maohong Fan Zaiyong Jiang School of Chemistry & Chemical Engineering and Environmental Engineering Weifang University Beijing Key Laboratory of Ionic Liquids Clean Process State Key Laboratory of Multiphase Complex Systems CAS Key Laboratory of Green Process and Engineering Institute of Process Engineering Chinese Academy of Sciences College Engineering and Physical Sciences and School of Energy Resources University of Wyoming

The catalyst layers(CLs) electrode is the key component of the membrane electrode assembly(MEA) in proton exchange membrane fuel cells(PEMFCs). Conventional electrodes for PEMFCs are composed of carbon-supported, ionomer, and Pt nanoparticles, all immersed together and sprayed with a micron-level thickness of CLs. They have a performance trade-off where increasing the Pt loading leads to higher performance of abundant triple-phase boundary areas but increases the electrode cost. Major challenges must be overcome before realizing its wide commercialization. Literature research revealed that it is impossible to achieve performance and durability targets with only high-performance catalysts, so the controllable design of CLs architecture in MEAs for PEMFCs must now be the top priority to meet industry goals. From this perspective, a 3D ordered electrode circumvents this issue with a support-free architecture and ultrathin thickness while reducing noble metal Pt loadings. Herein, we discuss the motivation in-depth and summarize the necessary CLs structural features for designing ultralow Pt loading electrodes. Critical issues that remain in progress for 3D ordered CLs must be studied and characterized. Furthermore, approaches for 3D ordered CLs architecture electrode development, involving material design, structure optimization, preparation technology, and characterization techniques, are summarized and are expected to be next-generation CLs for PEMFCs. Finally, the review concludes with perspectives on possible research directions of CL architecture to address the significant challenges in the future.

关键词： PEMFC 3D ordered electrode Structural features Preparation technology Ultralow Pt loading

Research progress on preparation of cerium-based oxide catalysts with specific morphology and their application for purification of diesel engine exhaust

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Journal of Rare Earths 2024年第7期42卷 1187-1216,I0001页

作者： Chunlei Zhang Siyu Gao Di Yu Shengran Zhou Lanyi wang Xuehua Yu zhen Zhao Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang110034China State Key Laboratory of Heavy Oil Processing China University of PetroleumBejing102249China

The elimination of pollutants from diesel exhaust has received widespread research attention as they cause serious air pollution and pose a threat to human *** post-treatment technology is one of the most effective and universal technologies to treat diesel exhaust *** design and development of efficient and low-cost catalysts is the key factor to realize the wide application of catalytic post-treatment ***(Ce)-based oxides with specific morphologies are widely used to eliminate pollutants in diesel vehicle exhaust due to their unique physical and chemical properties,such as high catalytic activity,low cost and *** this review,the preparation methods of Cebased oxide materials with specific morphologies,such as nanoparticles,nanocubes,nanorods,nanofibers,and multi-stage pores,are introduced in detail,and the research progress on using these catalysts for the removal of carbon monoxide,hydrocarbons,soot particles,nitrogen oxides,and other pollutants from diesel exhaust is reviewed in ***,the unresolved issues associated with using Ce-based oxide catalysts with a specific morphology to catalytically remove pollutants from diesel exhaust are highlighted,and future application prospects and development directions are discussed.

关键词： Ce-based oxide catalysts Dies elexhaust pollutants Specific morphology Catalytic purification Rare earths

Enhanced hepatic metabolic perturbation of polystyrene nanoplastics by UV irradiation-induced hydroxyl radical generation

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Journal of Environmental Sciences 2024年第8期142卷 259-268页

作者： Shiyu He Jingran wang Lihong Zhou zhen Mao Xiaodan Zhang Jin Cai Peili Huang School of Public Health and Beijing Key Laboratory of Environmental Toxicology Capital Medical UniversityBeijing 100069China

The environmental behavior of and risks associated with nanoplastics(NPs)have attracted considerable ***,compared to pristine NPs,environmental factors such as ultraviolet(UV)irradiation that lead to changes in the toxicity of NPs have rarely been *** evaluated the changes in morphology and physicochemical properties of polystyrene(PS)NPs before and after UV irradiation,and compared their hepatotoxicity in *** results showed that UV irradiation caused particle size reduction and increased the carbonyl index(CI)and negative charge on the particle ***-aged PS NPs(aPS NPs)could induce the generation of hydroxyl radicals(·OH),but also further promoted the generation of·OH in the Fenton reaction *** pathological damage was more severe in mice exposed to aPS NPs,accompanied by a large number of vacuoles and hepatocyte balloon-like changes and more marked perturbations in blood glucose and serum lipoprotein,alanine aminotransferase and aspartate aminotransferase *** addition,exposure to PS NPs and aPS NPs,especially aPS NPs,triggered oxidative stress and significantly damaged the antioxidant capacity of mice *** with PS NPs,exposure to aPS NPs increased the number of altered metabolites in hepatic and corresponding metabolic pathways,especially glutathione *** research suggests that UV irradiation can disrupt the redox balance in organisms by promoting the production of·OH,enhancing PS NPs-induced liver damage and metabolic *** study will help us understand the health risks of NPs and to avoid underestimation of the risks of NPs in nature.

关键词： Polystyrene nanoplastics Ultraviolet-aged nanoplastics Metabolic pathway Metabolomics Hydroxyl radical