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The Epidemiological Characteristics and Spatiotemporal Clustering of Measles—China,2005-2022

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China CDC weekly 2024年第27期6卷 665-669页

作者： Qianqian Liu Jiuhong Li siyu Liu Lin Tang Xiaoqi Wang Aodi Huang Xia Xu Yuexin Xiu Hong Yang Ning Wen Lance Rodewald Fuzhen Wang Zundong yin National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases National Immunization ProgramChinese Center for Disease Control and PreventionBeijingChina

Introduction:In recent years,the incidence of measles in China has consistently remained below 1 per 100,000 population,yet the disease has not been *** study aims to comprehensively analyze the epidemiological characteristics of measles from 2005 to 2022,identify high-risk populations and areas,and propose targeted ***:We utilized data from the China Disease Prevention and Control Information System for our comprehensive *** autocorrelation was employed to examine the spatial clustering of measles,while spatiotemporal scanning analysis was used to detect spatiotemporal clustering to describe measles epidemiology during the study ***:Between 2005 and 2022,732,218 measles cases were reported in ***,the incidence of measles exhibited a downward trend,particularly during the periods of 2008-2011 and *** 2022,the incidence rate reached its historical low at 0.039 per 100,000 *** predominantly affects young *** 2017,global spatial clustering has diminished,although hotspot areas persist in the western ***-temporal scanning identified a high-incidence cluster from 2005 to 2008,comprising 15 provinces in the western,central,and northern regions of ***,from 2016 to 2022,a low-incidence cluster was detected in the southern and central ***:China has made significant progress in measles prevention and *** recent low incidence and absence of substantial spatiotemporal clustering indicate that China is nearing measles ***,there is a continuing need to enhance prevention and control efforts among very young children and in historic incidence hotspots in western ***,improving the diagnosis of vaccine-associated rash illnesses is essential.

关键词： prevention Spatial utilized

Hybrid Modular Smart Transformer for Asymmetrically Bidirectional Power Flow Operation

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1384-1398页

作者： Kangan Wang Youngjong Ko Rongwu Zhu siyu Wu Weimin Wu Marco Liserre Shanghai Maritime University Shanghai 201306China Pukyong National University Busan 48513South Korea Harbin Institute of Technology(Shenzhen) Shenzhen 518000China Kiel University Kiel 24118Germany

The presence of renewable energy resources in LV distribution networks may lead to a distribution transformer,also known as a Smart Transformer(ST),experiencing the bidirectional power ***,the ST must have the capability to operate in both ***,the reverse power is less as compared to the forward power,thus the design of ST with the same capacity in both directions increases the hardware cost and decreases the system *** paper proposes a Hybrid-modular-ST(H-ST),composed of a mixed use of single active bridge-based series resonant converter and dual active bridge instead of complete use of uni-or bi-directional converter adopted in the conventional *** on the proposed H-ST,the impacts of power imbalance among cascaded modules in reverse operation mode are analyzed and then an effective solution based on reactive power compensation combined with the characteristics of the proposed architecture is *** simulation and experimental results clearly validate the effectiveness and feasibility of the theoretical analyses.

关键词： Cascaded H-bridge dual-active bridge series resonant converter smart transformer(ST) three-stage architecture

Process optimization and mechanism study of ionic liquid-based mixed amine biphasic solvents for CO_(2) capture in biogas upgrading procedure

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Frontiers of Environmental Science & Engineering 2024年第8期18卷 43-57页

作者： Fanzhi Meng siyu Han Li Lin Jinglin Li Kailun Chen Jianguo Jiang School of Environment Tsinghua UniversityBeijing 100084China

This study focused on enhancing the efficiency of methane upgrading and reducing energy consumption in the biogas upgrading process through the use of biphasic *** aqueous-based biphasic solvent,comprising methyl monoethanolamine(MMEA),N-methyldiethanolamine(MDEA),and 1-butyl-3-methylimidazolium tetrafluoroborate(ItFB),was meticulously *** biogas upgrading effect,regeneration efficiency,regeneration energy consumption,economic viability,selectivity,and phase separation characteristics of this absorbent were systematically *** parameters,including different inlet flow rates,stirring rate,methane inlet concentrations,reaction temperatures,and amine mixing ratios,were adjusted to investigate their impact.A comprehensive evaluation was conducted on the biogas upgrading effect and substance migration trends of the biphasic *** process parameters were determined,demonstrating the favorable impact of the biphasic solvent on biogas *** upgraded gas achieved a methane purity exceeding 96%,and the regeneration energy consumption decreased by 44.27% compared to 30 wt.%MEA,resulting in a more than 50% improvement in economic *** interaction between the ionic liquid and carbamate facilitated the phase separation process,with carbon enrichment after separation exceeding 95%.This enhancement significantly contributed to the improvement of regeneration energy *** study thus concludes that biphasic solvents,exemplified by the described aqueous-based solution,offer a promising avenue for effective biogas upgrading with notable advancements in economic and energy efficiency.

关键词： Biphasic solvents Biogas upgrading Energy consumption Process parameters Ionic liquid

A polarized^(3)He system based on metastability-exchange optical pumping

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 72-81页

作者： Yuting Wang Liangyong Wu Kaiyuan Zhang Mei Peng siyu Chen Haiyang Yan State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China Key Laboratory of Neutron Physics Institute of Nuclear Physics and ChemistryChina Academy of Engineering PhysicsMianyang 621900China

Hyperpolarized^(3)He nuclei have emerged as a significantly important approach in quantum precision measurement techniques,with extensive applications in fundamental physics,magnetometry,metrology,and *** this study,we report on the design and implementation of a^(3)He polarization system at the China Mianyang Research Reactor(CMRR),utilizing the metastabilityexchange optical pumping(MEOP)*** employed a Merritt coil system consisting of four square coils to furnish a uniform holding *** deployed a 2 W fiber laser to pump the metastable^(3)He atoms and conducted free induction decay(FID)detection of the polarized^(3)He nuclei using both pickup coil and optical *** the optical method,we used a50 m W linearly polarized distributed Bragg reflector(DBR)laser as the *** applied transverse light absorption polarimetry to measure the absolute nuclear polarization of the ground-state^(3)*** have developed cell fabrication capabilities at the CMRR,and cells at various pressures ranging from 100 to 1000 Pa have been fabricated and *** a typical borosilicate cell with 100 Pa pressure,the absolute polarization is measured as Pn≈70%,and the transverse relaxation time is estimated as T2≈0.5 ***,we constructed a few aluminosilicate cells,each carefully filled with pure^(3)He at a pressure of 100 ***,we conducted a comprehensive evaluation of their performance in the context of MEOP.

关键词： metastability exchange optical pumping polarized^(3)He magnetic resonance

Advances in poly(heptazine imide)/poly(triazine imide) photocatalyst

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Chinese Chemical Letters 2024年第10期35卷 102-125页

作者： Haojie Song Laiyu Luo siyu Wang Guo Zhang Baojiang Jiang Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People's Republic of ChinaSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150000China

Polymeric carbon nitride(PCN)has garnered increasing attention as a metal-free photocatalyst with a suitable band *** efforts to enhance its photocatalytic performance,researchers have examined various PCN materials,including poly(heptazine imide)(PHI)and poly(triazine imide)(PTI),two isomers within the PCN family that exhibit distinct and superior photocatalytic activity compared to other *** challenge,however,lies in the common practice among researchers to categorize PHI and PTI along with other PCN types under the overarching term“g-C_(3)N_(4),”which significantly impedes optimization *** objective of this review is to provide comprehensive insights into the structural features,photoelectrochemical properties,and effective characterization methods employed for distinguishing between PHI and PTI *** review also summarizes various optimization strategies,such as crystallinity adjustments,defect engineering,morphology control,constructing heterojunction,and atomic-level metal loading dispersion,to elevate the photocatalytic activity of PHI and PTI,in addition to summarizing the history of carbon nitride ***,this review highlights the primary applications of PHI and PTI,encompassing nitrogen fixation,biomass conversion,organic synthesis,CO_(2)reduction,pollutant degradation,H_(2)O_(2)production,and photocatalytic water ***,the prospects and challenges associated with further advancing PHI and PTI are thoroughly examined.

关键词： Poly(heptazine imide) Poly(triazine imide) Modification Photocatalytic Application

Investigation of surface textures deterioration on pavement skid-resistance using hysteresis friction models and numerical simulation method

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Friction 2024年第4期12卷 745-779页

作者： Haoyuan LUO siyu CHEN Leyi ZHU Xiyin LIU Yangzezhi ZHENG Runming ZHAO Xiaoming HUANG School of Transportation Southeast UniversityNanjing 211189China National Demonstration Center for Experimental Education of Road and Traffic Engineering Southeast UniversityNanjing 211189China

Many rubber friction theories or some method combined theories and field-experiments are employed to evaluate the pavement skid-resistance deterioration due to the evolution of surface ***,these methods are difficult to be implemented in the analysis of situations with multi-factor coupling and some extreme *** study developed a framework to evaluate the skid-resistance deterioration of asphalt *** this framework,the portable laser scanning was used to create the digital worn pavement model,and a hydroplaning finite element(FE)model for these digital worn pavements was constructed to evaluate coupling effects of the texture evolution and factors of slip ratio,slip angle,velocity and water film on braking-cornering characteristics of *** this study,the deterioration of skid-resistance of five typical asphalt pavements due the surface texture wear was systematically investigated by this *** with previous works,this study established the rubber friction models for each digital worn pavement considering the energy hysteresis of rubber and the power spectrum density of surface *** the rubber friction model was used to define the interaction behaviors between the tire and corresponding wore pavements in the FE hydroplaning model,rather than using an empirical friction model or a fixed friction coefficient.

关键词： worn pavement skid-resistance friction coefficient textures evolution water film computer numerical simulation

Quantitative analysis of the morphing wing mechanism of raptors: Analysis methods, folding motions, and bionic design of Falco Peregrinus

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Fundamental Research 2024年第2期4卷 344-352页

作者： Di Tang Xipeng Huang Jinqi Che Weijie Jin Yahui Cui Yangjun Chen Yuxiao Yuan Zhongyong Fan Weiwei Lu siyu Wang yin Yang Dawei Liu College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310014China Affiliated HangZhou XiXi hospital Zhejiang University School of MedicineHangzhou 310023China Zhejiang Museum of Natural History Hangzhou 310014China High Speed Aerodynamic Institute China Aerodynamics Research and Development CenterMianyang 621000China

Raptors can change the shape and area of their wings to an exceptional degree in a fast and efficient manner,surpassing other birds,insects,or *** researchers have focused on the functional properties of muscle skeletons,mechanics,and flapping robot ***,the wing motion of the birds of prey has not been measured quantitatively,and synthetic bionic wings with morphing abilities similar to raptors are far from ***,in the current study,a 3D suspension system for holding bird carcasses was designed and fabricated to fasten the wings of Falco Peregrinus with a series of morphing ***,the wing skeleton of the falcon was scanned during extending motions using the computed tomography(CT)approach to obtain three consecutive ***,the skeleton was reconstructed to identify the contribution of the forelimb bones to the extending/folding *** by these findings,we propose a simple mechanical model with four bones to form a wing-morphing mechanism using the proposed pose optimisation ***,a bionic wing mechanism was implemented to imitate the motion of the falcon wing—divided into inner and outer wings with folding and twisting *** results show that the proposed four-bar mechanism can track bone motion paths with high fidelity.

关键词： Falco Peregrinus Raptor Suspension system CT scan Bionic wings Four-bar mechanism

Quantifying the 2022 drought and spatiotemporal evolution of TWSA in the Dongting Lake Basin over the past two decades

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Geodesy and Geodynamics 2024年第5期15卷 516-527页

作者： Guodong Xu Sulan Liu siyu Cheng Yu Zhang Xiaohui Wu Yunlong Wu Institute of Seismology China Earthquake AdministrationWuhan 430071China School of Geography and Information Engineering China University of GeosciencesWuhan 430074China

Extreme hydrological events such as droughts and floods have been increasingly influenced by abnormal atmospheric disturbances caused by human activity and global *** Dongting Lake Basin(DLB)has experienced challenging circumstances over the past 20 years due to complex climatic variations,leading to extreme flooding and *** study aims to investigate the spatiotemporal variation in terrestrial water storage anomalies(TWSA)over the DLB using data from the GRACE/GRACE-FO and GLDAS spanning the latest two decades.A significant decline trend in TWSA is unveiled from July 2019 to May 2023,with the rate of change determined as-1.94 cm/year and-1.99 cm/year based on the GRACE/GRACE-FO and GLDAS,*** GRACE-Drought Severity Index(DSI)is employed to identify and evaluate the severity and spatiotemporal evolution of the 2022 drought event in the *** results accurately capture the drought event,which began in July 2022 and continued until March 2023,with the most severe conditions occurring in October 2022,when the GRACE-DSI value stood at-2.06 and the TWSA decreased by 15.24 cm and 33.51 cm relative to the same month in 2021 and 2020,***,the daily water level variation at the Chenglingji hydrological gauging station in 2022 broke previous records,reaching a minimum of only 19 *** the 2022 drought event with the drought events in 2006 and 2011,the impact of drought on vegetation growth conditions was relatively small,but there was still significant vegetation degradation across the DLB.

关键词： Dongting Lake drought Terrestrial water storage GRACE-DSI NDVI GRACE

A technical survey on mechanism and influence factors for asphalt pavement skid-resistance

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Friction 2024年第5期12卷 845-868页

作者： Xiyin LIU Haoyuan LUO Can CHEN Leyi ZHU siyu CHEN Tao MA Xiaoming HUANG School of Transportation Southeast UniversityNanjing211189China

To explore the research status on mechanism of the skid-resistance for asphalt pavement, the related achievements of the rubber friction, the tire–road contact, and the influence factors were reviewed. The rubber friction was reviewed from the mechanism and rubber friction model. The tire-road contact was studied from the modeling methods, the evaluation methods, and the skid-resistance mechanisms at different conditions. The influence factors of skid-resistance were summarized from different designing processes. This review showed that the appropriate contact or evaluation model should be selected according to the required parameters. Although the finite element method is widely used, the accuracy of the model, the boundary conditions, and the load cases need to be further improved. The optimized aggregates and asphalt binders, reasonable gradation, reasonable geometric design, and strict construction quality control are necessary for good initial skid-resistance. Pavement texture as an important factor affecting skid-resistance should be considered in pavement gradation design, especially for wearing layer technology.

关键词： asphalt pavement rubber friction tire-road contact skid-resistance