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Reaction Kinetics and Secondary Organic Aerosol Composition Analysis of 2-Cyclohexen-1-one with NO3 Radicals

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Chemical Research in Chinese Universities 2024年第4期40卷 730-736页

作者： hu Lin tong Shengrui XU Yanyong ZHANG Hailiang YU Shanshan CHEN Meifang GE Maofa Structural Chemistry of Unstable and Stable Species Chinese Academy of Sciences Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing100190P.R.China College of Ecology and Environment Xinjiang UniversityUrumqi830017P.R.China University of Chinese Academy of Sciences Beijing100049P.R.China

Unsaturated ketones are typical oxygenated volatile organic compounds(OVOCs)with high reactivity,and are important precursors in air *** sources of OVOCs are complex and include direct emissions and secondary oxidation formation of VOCs in the atmosphere.2-Cyclohexen-1-one is a widespread substance,and is derived from the industrial catalytic oxidation of *** this paper,we investigated the rate constants of the chemical reactions of 2-cyclohexen-1-one with NO3 radicals,which is(7.25±0.29)×10^(-15) cm^(3)·molecule^(-1)·s^(-1) at 298 K and under 1 atm(1 atm=101325Pa).It supplemented the kinetics of NO3 radicals database,and revealed its effects in the nighttime *** addition,the reaction products of 2-cyclohexen-1-one with NO3 radicals were detected by Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS),which revealed a series of nitrate esters in the composition of the secondary organic aerosol(SOA),which may reduce atmospheric ***,the possible pathways for the generation of the products were developed.

关键词： Kinetics Unsaturated ketone Nitrate radical Secondary organic aerosol

Gradient-structure-enhanced dielectric energy storage performance of flexible nanocomposites containing controlled preparation of defective TiO_(2) and ferroelectric KNbO_(3) nanosheets

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Nano Research 2024年第5期17卷 4079-4088页

作者： Yan Wang Lili zhao Ruicong Chen Wenhui zhao Dengwei hu Haoran Wang Bin Cui Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education Shaanxi Key Laboratory of Physico–Inorganic Chemistry Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China School of Information Science and Technology Northwest UniversityXi’an 710127China Engineering Research Center for Titanium Based Functional Materials and Devices in Universities of Shaanxi Province Faculty of Chemistry and Chemical EngineeringBaoji University of Arts and SciencesBaoji 721013China

Next generation power system needs dielectrics with increased dielectric energy ***,the low energy density of dielectrics limits their ***,an asymmetric trilayered nanocomposite,with a transition layer(TL),an insulation layer(IL),and a polarization layer(PL),is designed based on poly(vinylidene fluoride)-polymethyl methacrylate(PVDF-PMMA)matrix using KNbO_(3)(KN)and TiO_(2)(TO)as the *** morphology and defect control of the two-dimensional nano KN and nano TO fillers are realized via a hydrothermal method to increase the composite breakdown strength(E_(b))and the composite energy density(U_(e)).The asymmetric trilayered structure leads to a gradient electric field distribution,and the KN and TO nanosheets block charges transfer along z *** a result,the development path of the electrical trees is greatly curved,and E_(b) is effectively *** the Ue value of the nanocomposites reaches 17.79 J·cm^(-3) at 523 MV·m^(-1).On the basis,the composite Ue is further improved by defect control in TO *** nanocomposite KN/TO/PVDF-PMMA containing TO with less oxygen vacancy concentration(calcined at oxygen atmosphere)acquires a high Ue of 21.61 J·cm^(-3) at 548 MV·m^(-1).This study provides an idea for improving the energy storage performance by combining the design of the composite dielectric structure and the control of nanofillers’defect and morphology.

关键词： asymmetric trilayered structure two-dimensional energy density oxygen vacancies breakdown strength dielectric

Disease Burden and Costs Associated with Multiple Sclerosis in China:A Cross-sectional Analysis of Nationwide Survey Data

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Neuroscience Bulletin 2024年第4期40卷 533-538页

作者： Yusheng Jia Xuanqi Qiao Jin zhao Hainan Li Shanlian hu Min hu Department of Health Economics School of Public HealthFudan UniversityShanghai200032China National Health Commission Key Laboratory of Health Technology Assessment Fudan UniversityShanghai200032China

DearEditors,Multiple sclerosis(MS)is a chronic,autoimmune neurological disorder characterized by inflammatory demyelination of the central nervous system;it is associated with reduced mobility,cognitive impairment,and numerous comorbidities[1].Global MS incidence(2.1 per 100,000 person-years)and prevalence(30.1 per 100,000)have increased in recent years,and its prevalence is notably higher in Western countries,ranging from~30 to 200 cases per 100,000[2].In China,recent epidemiological research has shown that the crude prevalence was 2.44 per 100,000 in 2016[3],and the age-and sex-adjusted incidence was 0.235 per 100,000 person-years[4].Despite the relatively low prevalence compared with the global average,China has extensively addressed the well-being of over 30,000 MS patients,enrolling MS in China's First National List of Rare Diseases in 2018.

关键词： prevalence impairment autoimmune

Laparoscopic enucleation for pancreatic lipomatous hamartoma

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 541-544页

作者： Da-Long Wan Rong-Liang tong Xin-Yu tong Chen hu Qing-Hong Ke Xu Yang Jian Wu Department of Hepatobiliary and Pancreatic Surgery the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Pathology the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

To the Editor : Pancreatic hamartoma is an extremely rare and benign disease and accounts for less than 1% of all pancreatic tumors [1]. Pancreatic lipomatous hamartoma(PLH), a distinct variant of pancreatic hamartoma, is always easily misdiagnosed as other pancreatic tumors with lipomatous components, including pancreatic lipoma, liposarcoma, teratoma and malignant tumors with fatty degeneration. Here, we report a case of laparoscopic enucleation for the pancreatic head lipomatous hamartoma and provide new treatment strategies for surgeons who encounter similar diseases in the future.

关键词： degeneration Laparoscopic diseases

The joint knowledge reasoning model based on knowledge representation learning for aviation assembly domain

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Science China(Technological Sciences) 2024年第1期67卷 143-156页

作者： LIU PeiFeng QIAN Lu LU hu XUE Lei zhao XingWei TAO Bo State Key Laboratory of Digital Manufacturing Equipment and Technology Department of MechanicalHuazhong University of Science and TechnologyWuhan 430074China School of Transportation and Logistics Engineering Wuhan University of Technology(WHUT)Wuhan 430063China Shanghai Aircraft Manufacturing Co. Ltd.Shanghai 201324China

Knowledge graph technology is widely applied in the domain of general knowledge reasoning with an excellent *** fine-grained professional fields,professional knowledge graphs can provide more accurate information in practical industrial *** on an aviation assembly domain-specific knowledge graph,the article constructs a joint knowledge reasoning model,which combines a named entity recognition model and a subgraph embedding learning *** performing knowledge reasoning tasks,the two models vectorize entities,relationships and entity attributes in the same space,so as to share parameters and optimize learning *** knowledge reasoning model,which provides intelligent question answering services,is able to reduce the assembly error rate and improve the assembly *** system can accurately solve general knowledge reasoning problems in the assembly process in actual industrial scenarios of general assembly and component assembly under interference-free ***,this paper compares the proposed knowledge reasoning model based on knowledge representation learning and the question-answering system based on large-scale pre-trained *** the application scenario of system functional testing in general assembly,the joint model attains an accuracy rate of 95%,outperforming GPT with 78%accuracy and enhanced representation through knowledge integration with 71%accuracy.

关键词： intelligent manufacturing knowledge graph aviation assembly knowledge representation knowledge-based question an-swering

Deep learning-based inpainting of saturation artifacts in optical coherence tomography images

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Journal of Innovative Optical Health Sciences 2024年第3期17卷 1-10页

作者： Muyun hu Zhuoqun Yuan Di Yang Jingzhu zhao Yanmei Liang Institute of Modern Optics Nankai UniversityTianjin Key Laboratory of Micro-scale Optical Information Science and TechnologyTianjin 300350China Department of Thyroid and Neck Tumor Tianjin Medical University Cancer Institute and Hospital National Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjin 300060China

Limited by the dynamic range of the detector,saturation artifacts usually occur in optical coherence tomography(OCT)imaging for high scattering *** available methods are difficult to remove saturation artifacts and restore texture completely in OCT *** proposed a deep learning-based inpainting method of saturation artifacts in this *** generation mechanism of saturation artifacts was analyzed,and experimental and simulated datasets were built based on the *** super-resolution generative adversarial networks were trained by the clear–saturated phantom image *** perfect reconstructed results of experimental zebrafish and thyroid OCT images proved its feasibility,strong generalization,and robustness.

关键词： Optical coherence tomography saturation artifacts deep learning image inpainting.

YOLOv5ST:A Lightweight and Fast Scene Text Detector

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Computers, Materials & Continua 2024年第4期79卷 909-926页

作者： Yiwei Liu Yingnan zhao Yi Chen Zheng hu Min Xia School of Computer and Science Nanjing University of Information Science and TechnologyNanjing210044China School of Automation Nanjing University of Information Science and TechnologyNanjing210044China

Scene text detection is an important task in computer *** this paper,we present YOLOv5 Scene Text(YOLOv5ST),an optimized architecture based on YOLOv5 v6.0 tailored for fast scene text *** primary goal is to enhance inference speed without sacrificing significant detection accuracy,thereby enabling robust performance on resource-constrained devices like drones,closed-circuit television cameras,and other embedded *** achieve this,we propose key modifications to the network architecture to lighten the original backbone and improve feature aggregation,including replacing standard convolution with depth-wise convolution,adopting the C2 sequence module in place of C3,employing Spatial Pyramid Pooling Global(SPPG)instead of Spatial Pyramid Pooling Fast(SPPF)and integrating Bi-directional Feature Pyramid Network(BiFPN)into the *** results demonstrate a remarkable 26%improvement in inference speed compared to the baseline,with only marginal reductions of 1.6%and 4.2%in mean average precision(mAP)at the intersection over union(IoU)thresholds of 0.5 and 0.5:0.95,*** work represents a significant advancement in scene text detection,striking a balance between speed and accuracy,making it well-suited for performance-constrained environments.

关键词： Scene text detection YOLOv5 lightweight object detection

Assessment of Wet Season Precipitation in the Central United States by the Regional Climate Simulation of the WRFG Member in NARCCAP and Its Relationship with Large-Scale Circulation Biases

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Advances in Atmospheric Sciences 2024年第4期41卷 619-638页

作者： Yating zhao Ming XUE Jing JIANG Xiao-Ming hu Anning huANG School of Atmospheric Sciences Nanjing UniversityNanjing 210023China Center for Analysis and Prediction of Storms and School of Meteorology The University of OklahomaNorman 73072U.S.A

Assessment of past-climate simulations of regional climate models(RCMs)is important for understanding the reliability of RCMs when used to project future regional ***,we assess the performance and discuss possible causes of biases in a WRF-based RCM with a grid spacing of 50 km,named WRFG,from the North American Regional Climate Change Assessment Program(NARCCAP)in simulating wet season precipitation over the Central United States for a period when observational data are *** RCM reproduces key features of the precipitation distribution characteristics during late spring to early summer,although it tends to underestimate the magnitude of *** dry bias is partially due to the model’s lack of skill in simulating nocturnal precipitation related to the lack of eastward propagating convective systems in the *** in reproducing large-scale circulation and environmental conditions is another contributing *** too weak simulated pressure gradient between the Rocky Mountains and the Gulf of Mexico results in weaker southerly winds in between,leading to a reduction of warm moist air transport from the Gulf to the Central Great *** simulated low-level horizontal convergence fields are less favorable for upward motion than in the NARR and hence,for the development of moist convection as ***,a careful examination of an RCM’s deficiencies and the identification of the source of errors are important when using the RCM to project precipitation changes in future climate scenarios.

关键词： NARCCAP Central United States precipitation low-level jet large-scale environment diurnal variation

Hierarchical V_(3)S_(4)/C nanofibers with fast kinetics for superior alkali metal batteries

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Rare Metals 2024年第4期43卷 1836-1844页

作者： Li Chen Zhi-Xin Rao Zhi Chen zhao-hui Wu Shuai Yang Zhi-Jun Feng hui-Yong Yang Fan-Yan Zeng Xi-Bao Li Jin-Yang hu Jun-tong huang School of Materials Science and Engineering Nanchang Hangkong UniversityNanchang330063China School of Aeronautical Manufacturing Engineering Nanchang Hangkong UniversityNanchang330063China

Owing to the numerous benefits,including low cost and great theoretical capacity,V3S4 has been a research hotspot for Li^(+)/Na^(+)/K^(+) ***,the V_(3)S_(4) electrode with long cycling stability and high specific capacities continues to pose significant *** this work,vacuum vulcanization is combined with electrospinning to synthesize V_(3)S_(4)/C composite nanofibers(V_(3)S_(4)@CNF).

关键词： composite fibers kinetics