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Journal of Thermal Science 2024年第1期33卷 101-113页

作者： yuan Baoqiang wang Wei XIN Gongming DU Wenjing School of Energy and Power Engineering Shandong UniversityJi'nan 250061China

Large eddy simulations have been conducted to study upward transitional flows and heat transfer characteristics of supercritical CO_(2) in a vertical *** numerical simulation was carried out on a modified buoyantPimpleFOAM solver in OpenFOAM 7,and was verified using experiment *** results indicate that increasing the Grashof numbers can reduce the flow stability and make the flow transition *** are four stages of heat transfer in the transition process,i.e.,weakened,improved,recovered and normal heat *** heat transfer phenomena in the transition process were explained from three perspectives:thermal boundary layer theory,turbulent transport and pseudo-boiling *** transfer enhancement during transition is related to the transport of supercritical molecular clusters,and these molecular clusters are regarded as pseudo-bubbles in pseudo-boiling *** flow pattern of the pseudo-phases in the dia-Widom process contains single-phase flow,steady pseudo-film flow,unsteady pseudo-film flow,partial pseudo-bubbles flow and flocculent pseudo-film ***-bubbles have similar behaviors to subcritical bubbles,i.e.,break-up,deformation,condensation and *** researches in this work are favorable for understanding the heat transfer mechanism of supercritical fluids during flow transition.

关键词： supercritical heat transfer large eddy simulation transition pseudo-boiling

Digitalizing river aquatic ecosystems

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Journal of Environmental Sciences 2024年第3期137卷 677-680页

作者： Yaohui Bai hui Lin Chenchen wang Qiaojuan wang Jiuhui Qu Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China School of Environmental and Municipal Engineering Tianjin Chengjian UniversityTianjin 300384China Center for Water and Ecology Tsinghua UniversityBeijing 100084China

Traditional river health assessment relies on limited water quality indices and representative organism activity,but does not comprehensively obtain biotic and abiotic information of the ***,we propose a new approach to evaluate the ecological and health risks of river aquatic ***,detailed physicochemical and biological characterization of a river ecosystem can be obtained through pollutant determination(especially emerging pollutants)and DNA/RNA ***,supervised machine learning can be applied to perform classification analysis of characterization data and ascertain river ecosystem ecology and *** proposed methodology transforms river ecosystem health assessment and can be applied in river management.

关键词： Digitalizing River ecosystem health Emerging pollutants High throughput sequencing Machine learning

The Investigation of Data Voting Algorithm for Train Air-Braking System Based on Multi-Classification SVM and ANFIS

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Chinese Journal of Electronics 2024年第1期33卷 274-281页

作者： Juhan wang Ying GAO yuan CAO Tao TANG School of Electronics and Information Engineering Beijing Jiaotong University Graduate Department China Academy of Railway Science National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University

The pressure data of the train air braking system is of great significance to accurately evaluate its operation state. In order to overcome the influence of sensor fault on the pressure data of train air braking system, it is necessary to design a set of sensor fault-tolerant voting mechanism to ensure that in the case of a pressure sensor fault, the system can accurately identify and locate the position of the faulty sensor, and estimate the fault data according to other normal data. A fault-tolerant mechanism based on multi-classification support vector machine(SVM) and adaptive network-based fuzzy inference system(ANFIS) is introduced. Multi-classification SVM is used to identify and locate the system fault state, and ANFIS is used to estimate the real data of the fault sensor. After estimation, the system will compare the real data of the fault sensor with the ANFIS estimated data. If it is similar,the system will recognize that there is a false alarm and record it. Then the paper tests the whole mechanism based on the real data. The test shows that the system can identify the fault samples and reduce the occurrence of false alarms.

关键词： Support vector machines Fault diagnosis Pressure sensors Fuzzy logic Fault tolerance Adaptive systems Fault tolerant systems

Effect of Magnetic Field Configuration on Stray-Crystal Formation with Different Platform Sizes during Directional Solidification of Single-Crystal Superalloy

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 904-914页

作者： Keke Lu Congjiang Zhang Xiaotan yuan Hongbin Yu Weili Ren Biao Ding Haibiao Lu Yunbo Zhong Zuosheng Lei hui wang Qiuliang wang Peter KLiaw Xuezhi Qin Lanzhang Zhou State Key Laboratory of Advanced Special Steel Shanghai Key Laboratory of Advanced FerrometallurgyShanghai UniversityShanghai 200444China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China Department of Materials Science and Engineering The University of TennesseeKnoxvilleTN 37996USA Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

The magnetic field is an effective means to control the solidification structure and the defects of metal and semiconductor *** work investigates the effects of Cusp magnetic field(CMF)and longitudinal magnetic field(LMF)on the stray-crystal formation in the platform regions during the directional solidification of single-crystal superalloy with the different cross section *** application of CMF reduces the formation of platform stray-crystal,while LMF increases its *** the platform size increases,the stray-crystal ratio increases regardless of whether the magnetic fields are applied or not,the effectiveness of CMF increases,while that of LMF *** reason that the effects of CMF and LMF on the platform stray-crystal formation could be attributed to the change of flow structure from the distribution characteristics of the thermoelectric magnetic force and the magnetic damping force near the liquid-solid interface.

关键词： Stray-crystal Magnetic field Single-crystal superalloy Cross section change Directional solidification

Reducibility of Three Dimensional Skew Symmetric System with High Dimensional Weak Liouvillean Frequencies

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Acta Mathematica Sinica,English Series 2024年第10期40卷 2388-2410页

作者： Jie LIU yuan SHAN Jing wang School of Mathematics and Statistics Nanjing University of Science and Technology School of Statistics and Data Science Nanjing Audit University

In this paper, we consider the reducibility of three-dimensional skew symmetric *** obtain a reducibility result if the base frequency is high-dimensional weak Liouvillean and the parameter is sufficiently small. The ... 详细信息

关键词： 34C20 37J40 high-dimensional weak Liouvillean KAM theory three dimensional skew-symmetric system

Heat exposure and hospitalizations for chronic kidney disease in China: a nationwide time series study in 261 major Chinese cities

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Military Medical Research 2024年第4期11卷 469-478页

作者： Fu-Lin wang Wan-Zhou wang Fei-Fei Zhang Su-yuan Peng Huai-Yu wang Rui Chen Jin-Wei wang Peng-Fei Li Yang wang Ming-hui Zhao Chao Yang Lu-Xia Zhang Institute of Medical Technology Peking University Health Science CenterBeijing 100191China National Institute of Health Data Science at Peking University Beijing 100191China Department of Occupational and Environmental Health Sciences School of Public HealthPeking UniversityBeijing 100191China Renal Division Department of MedicinePeking University First HospitalPeking University Institute of NephrologyBeijing 100034China Research Units of Diagnosis and Treatment of Immune-Mediated Kidney Diseases Chinese Academy of Medical SciencesBeijing 100034China Advanced Institute of Information Technology Peking UniversityHangzhou 311215China National Climate Center China Meteorological AdministrationBeijing 100081China Peking-Tsinghua Center for Life Sciences Beijing 100034China

Background:Climate change profoundly shapes the population health at the global ***,there was still insufficient and inconsistent evidence for the association between heat exposure and chronic kidney disease(CKD).Methods:In the present study,we studied the association of heat exposure with hospitalizations for cause-specific CKD using a national inpatient database in China during the study period of hot season from 2015 to *** time-series regression models and random-effects Meta-analysis were developed to estimate the city-specific and national averaged associations at a 7 lag-day span,***:A total of 768,129 hospitalizations for CKD was recorded during the study *** results showed that higher temperature was associated with elevated risk of hospitalizations for CKD,especially in sub-tropical *** a 1℃ increase in daily mean temperature,the cumulative relative risks(RR)over lag 0-7 d were 1.008[95% confidence interval(CI)1.003-1.012]for *** attributable fraction of CKD hospitalizations due to high temperatures was 5.50%.Stronger associations were observed among younger patients and those with obstructive *** study also found that exposure to heatwaves was associated with added risk of hospitalizations for CKD compared to non-heatwave days(RR=1.116,95%CI 1.069-1.166)above the effect of daily mean ***:Short-term heat exposure may increase the risk of hospitalization for *** findings provide insights into the health effects of climate change and suggest the necessity of guided protection strategies against the adverse effects of high temperatures.

关键词： Chronic kidney disease Hospitalization Climate change Temperature Time-series study

Interleukins in Epilepsy:Friend or Foe

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Neuroscience Bulletin 2024年第5期40卷 635-657页

作者： yuan Dong Xia Zhang Ying wang Neuropsychiatry Research Institute The Affiliated Hospital of Qingdao UniversityQingdao UniversityQingdao266000China Program in Cellular and Molecular Medicine Boston Children’s HospitalBostonMA02115USA

Epilepsy is a chronic neurological disorder with recurrent unprovoked seizures,affecting~65 million *** in patients with epilepsy and animal models suggests a contribution of neuroinflammation to epileptogenesis and the development of ***(ILs),as one of the major contributors to neuroinflammation,are intensively studied for their association and modulatory effects on ictogenesis and *** are commonly divided into pro-and anti-inflammatory cytokines and therefore are expected to be pathogenic or neuroprotective in ***,both protective and destructive effects have been reported for many *** may be due to the complex nature of ILs,and also possibly due to the different disease courses that those ILs are involved *** this review,we summarize the contributions of different ILs in those processes and provide a current overview of recent research advances,as well as preclinical and clinical studies targeting ILs in the treatment of epilepsy.

关键词： Epilepsy Interleukins Neuroinflammation

Complex interactions among insect viruses-insect vector-arboviruses

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Insect Science 2024年第3期31卷 683-693页

作者： hui wang Qian Chen Taiyun Wei State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops Vector-borne Virus Research CenterFujian Agriculture and ForestryUniversityFuzhouChina

Insects are the host or vector of diverse viruses including those that infect vertebrates,plants,and *** viruses reside inside their insect hosts and are vertically transmitted from parent to *** insect virus-host relationship is intricate,as these viruses can impact various aspects of insect biology,such as development,reproduction,sex ratios,and ***-borne viruses(arboviruses)that cause substantial global health or agricultural problems can also be vertically transmitted to insect vector *** infections with insect viruses and arboviruses are common in *** coinfections involve complex interactions,including synergism,dependence,and *** studies have shed light on the influence of insect viruses on the competence of insect vectors for *** this review,we focus on the biological effects of insect viruses on the transmission of arboviruses by *** also discuss the potential mechanisms by which insect viruses affect the ability of hosts to transmit arboviruses,as well as potential strategies for disease control through manipulation of insect *** of the interactions among insect vectors,insect viruses and arboviruses will provide new opportunities for development of innovative strategies to control arbovirus transmission.

关键词： arbovirus insect biology insect vectors insect virus interaction transmission

Effect of antioxidants on the efficiency of jet milling and the powder characteristics of Sm2Co17 permanent magnets

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Chinese Physics B 2024年第9期33卷 615-620页

作者： Da-Shuai Xu Lei Liu Jian-hui yuan Bo Zhou Chuang-hui Dong Feng-Qing wang Yong Ding Ying-Li Sun A-Ru Yan School of Materials Science and Engineering Shanghai University of Engineering ScienceShanghai 201620China CISRI&NIMTE Joint Innovation Center for Rare Earth Permanent Magnets CAS Key Laboratory of Magnetic Materials and DevicesZhejiang Province Key Laboratory of Magnetic Materials and Application TechnologyNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China University of Chinese Academy of Sciences Beijing 100049China

This study investigated the effect of antioxidants on the grinding efficiency,magnetic powder characteristics,microstructure,and magnetic properties of 2:17 type SmCo permanent magnet *** results show that adding antioxidants helps improve the dispersion among magnetic powders,leading to a 33.3%decrease in jet milling time and a 15.8%increase in magnet powder production ***,adding antioxidants enhances the oxidation resistance of the magnetic *** being stored in a constant temperature air environment at 25C for 48 h,the O content in the powder decreased by 33%compared to samples without *** in the magnet body,the O content decreased from 0.21 wt.%to 0.14 wt.%,which helps increase the effective Sm content and domain wall pinning uniformity in the *** magnetic properties were obtained in the magnet with added antioxidants:B_(r)=11.6 kGs,SF=79.6%,H_(cj)=16.8 kOe,and(BH)_(max)=32.5 MGOe.

关键词： antioxidant SmCo permanent magnet oxidation resistance grinding efficiency

Local Hamilton type Gradient Estimates and Harnack Inequalities for Nonlinear Parabolic Equations on Riemannian Manifolds

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 539-546页

作者： Wen wang Da-peng XIE hui ZHOU School of Mathematics and Statistics Hefei Normal UniversityHefei 230601China

In this paper,we prove a local Hamilton type gradient estimate for positive solution of the nonlinear parabolic equation ut(x,t)=Δu(x,t)+au(x,t) ln u(x,t)+bu^(α)(x,t),on M×(-∞,∞) with α∈R,where a and b are *** ... 详细信息

关键词： nonlinear parabolic equation gradient estimate Harnack inequality