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永磁电动悬浮多工况下的电磁力特性研究

电工技术学报 2024年第17期39卷 5262-5277页

作者：曹婷石洪富刘峻志吴学杰邓自刚西南交通大学轨道交通运载系统全国重点实验室成都610031 西南交通大学信息科学与技术学院成都610031

永磁电动悬浮系统由于自身弱阻尼的特点,运行过程中磁体的姿态易受外界扰动而发生改变,从而影响系统的电磁力特性。该文针对磁体倾斜、横移、偏转等工况,采用解析计算、仿真分析、实验验证相结合的方法来研究系统电磁力特性。首先阐述... 详细信息

永磁电动悬浮系统由于自身弱阻尼的特点,运行过程中磁体的姿态易受外界扰动而发生改变,从而影响系统的电磁力特性。该文针对磁体倾斜、横移、偏转等工况,采用解析计算、仿真分析、实验验证相结合的方法来研究系统电磁力特性。首先阐述系统的结构及原理,推导Halbach永磁体阵列在水平、倾斜、偏转状态下的磁场分布函数,建立适用于系统多工况的三维解析模型;其次,搭建三维仿真模型,仿真结果验证了解析模型的正确性,并结合解析模型对比分析系统典型工况下的浮阻特性和悬浮能力;最后,依托组内自研的最高设计时速为600km/h的动轨实验台,分析了系统在固定参数下的电磁力特性和垂向自稳定能力,并验证解析模型的准确性及磁体在不同横移位置的电磁力特性。

关键词：永磁电动悬浮多工况电磁力特性解析计算高速实验台 Halbach阵列

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河流碳循环模型研究进展

地球科学进展 2024年第2期39卷 111-123页

作者：刘娇娇刘军志宋超张蔚珍刘勇勤兰州大学泛第三极环境中心甘肃兰州730000 兰州大学大气科学学院甘肃兰州730000 兰州大学生态学院甘肃兰州730000 中国科学院青藏高原环境变化与地表过程重点实验室北京100101 中国科学院大学北京100049

河流是连接陆地和海洋两大碳库的“重要管道”和“生物反应器”,深入理解河流碳循环过程并建立河流碳循环模型是估算区域尺度河流碳通量的重要手段。当前,对河流碳循环模型构建与应用的探讨还较为缺乏。通过文献调研对河流碳循环机理和... 详细信息

河流是连接陆地和海洋两大碳库的“重要管道”和“生物反应器”,深入理解河流碳循环过程并建立河流碳循环模型是估算区域尺度河流碳通量的重要手段。当前,对河流碳循环模型构建与应用的探讨还较为缺乏。通过文献调研对河流碳循环机理和已有模型研究进行回顾和总结,首先归纳了河流中颗粒有机碳、溶解有机碳和溶解无机碳的主要来源及相关迁移转化过程,然后对经验统计和机理过程两大类河流碳循环模型的模拟方法、应用现状和优缺点进行了综述。经验统计模型采用统计或机器学习方法建立河流碳通量与环境因子的关系,建模较为简单,但普适性和外推性较差;机理过程模型在陆面模式或水文模型中耦合河流碳循环相关过程,物理性和可靠性较强,但较为复杂。不同模型的侧重点和对河流碳循环过程的表达各不相同,适用场景也不相同。河流碳循环模拟研究目前尚处于起步阶段,现有模型对陆地和水体碳循环过程以及人类活动影响的表达普遍不足,无法准确模拟和预测河流碳循环过程的长期变化。今后应加强对河流碳循环过程的观测,提高对陆地和水体碳循环机理的认识,进而完善其在模型中的表达,提高河流碳循环模拟的精度,为中国实现“双碳”目标提供科学支撑。

关键词：陆—水—气交换碳收支河流系统经验统计模型过程机理模型

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电大山区地物环境中电波传播的电磁计算

西安电子科技大学学报 2024年第1期51卷 21-28页

作者：王楠刘俊志陈贵齐赵延安张玉西安电子科技大学电子工程学院陕西西安710071 国家无线电检测中心陕西监测站陕西西安710200

在无人驾驶与无人机等新兴行业中,信号覆盖范围的要求较高,不仅仅在城市,在人迹罕至的山地、沙漠、森林中也需要无线信号的覆盖才能真正完成远程操控,这些地区更多需要考虑的是地势变化对电磁传播所带来的影响。计算电磁学中的一致性几... 详细信息

在无人驾驶与无人机等新兴行业中,信号覆盖范围的要求较高,不仅仅在城市,在人迹罕至的山地、沙漠、森林中也需要无线信号的覆盖才能真正完成远程操控,这些地区更多需要考虑的是地势变化对电磁传播所带来的影响。计算电磁学中的一致性几何绕射理论方法是分析电大环境电磁问题的有效方法,使用计算电磁学的方法研究电磁波在山区地物环境中的传播规律。给出了一种建立不规则地形模型的新方法,可以通过数字高程的网格数据生成电磁算法可用的三次多项式曲面,使用多个立方曲面对不规则地形进行拼接,使用平均均方根误差验证模型数据的准确性。基于所得的地形数据,完成了并行的几何光学算法,并对区域电磁场的分布进行了仿真计算。选取了实际山区地物环境进行了实地测量,测量结果与仿真结果对比趋势一致,验证了该方法在非规则地形中电磁波传播分析中的有效性。考虑环境电磁计算的规模,建立了相应的并行策略,100核测试的并行效率可以保持在80%以上。

关键词：电大山区地物环境电波传播数字高程分形建模几何光学并行计算

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Effect of Polyisobutylene Succinimide on the Physical Stability of an Environmentally Friendly Pesticide Oil Dispersion Suspension

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Journal of Renewable Materials 2023年第6期11卷 2679-2694页

作者： Liying Wang junzhi liu Chong Gao Xinxin Yan Institute of Functional Molecules Shenyang University of Chemical TechnologyShenyang110142China

Oil dispersible suspension concentrates are safe,green,and environmentally friendly *** such as layering,pasting,and bottoming are frequently encountered during the production,storage,and transportation *** succinimide functions as a dispersant and exhibits great potential to improve the physical stability of the oil dispersible suspension *** a microscopic perspective,the sorption characteristics of the polyisobutylene succinimide dispersant T151 on penoxsulam particle surfaces were comprehensively evaluated with XPS,FTIR,and *** T151 adsorption procedure complied with a pseudo-second-order kinetic adsorption model,and it was a kind of physical sorption with an Ea of 22.57 kJ⋅mol^(−1).The T151 sorption model was consistent with the Langmuir *** adsorption process was spontaneous and followed by an entropy ***ΔH^(θ)of dispersant T151 on the surface of penoxsulam particles was 31.59 kJ⋅mol^(−1).The adsorption procedure was endothermic,and the primary force was hydrogen *** XPS results showed that the F and S electronic peaks at the penoxsulam interface decreased,and that the C electronic peak increased significantly after the adsorption of dispersant T151,indicating the adsorption on the surface of penoxsulam *** results of this study provide a vital theoretical basis for the application of polyisobutylene succinimide dispersants in oil dispersible suspension systems.

关键词： Polyisobutylene succinimide oil dispersion suspension penoxsulam physical stability

急性一氧化碳中毒迟发性脑病预测方法的现状及进展

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长春中医药大学学报 2024年第5期40卷 581-585页

作者：王霈雯滕登科谭诚刘俊志吉林大学中日联谊医院长春130033

急性一氧化碳中毒迟发性脑病(delayed encephalopathy after acute carbon monoxide poisoning,DEACMP)发病隐匿、病程较长、致残率高,主要表现为精神意识的障碍。尽管早期预测DEACMP的发生有助于改善预后、减少后遗症的发生,但如何对DE... 详细信息

急性一氧化碳中毒迟发性脑病(delayed encephalopathy after acute carbon monoxide poisoning,DEACMP)发病隐匿、病程较长、致残率高,主要表现为精神意识的障碍。尽管早期预测DEACMP的发生有助于改善预后、减少后遗症的发生,但如何对DEACMP进行准确的预测一直是临床上急需解决的难点问题。近年来,对DEACMP的预测从临床表现、实验室指标、神经电生理检查、影像学检查及遗传易感性等方面均取得了一定的进展,临床医生需要综合研判,预测迟发性脑病的发生,及时进行干预。

关键词：急性一氧化碳中毒迟发性脑病预测

On-surface synthesis and edge states of NBN-doped zigzag graphene nanoribbons

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Nano Research 2023年第7期16卷 10436-10442页

作者： Xiao Chang Li Huang Yixuan Gao Yubin Fu Ji Ma Huan Yang junzhi liu Xiaoshuai Fu Xiao Lin Xinliang Feng Shixuan Du Hong-Jun Gao University of Chinese Academy of Sciences Beijing 100190China Beijing National Center for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Center for Advancing Electronics Dresden(CfAED)and Faculty of Chemistry and Food Chemistry Technische Universität DresdenDresden D-01069Germany Max Planck Institute of Microstructure Physics Weinberg 2Halle 06120Germany Department of Chemistry State Key Laboratory of Synthetic ChemistryThe University of Hong KongHong Kong 999077China Songshan Lake Materials Laboratory Dongguan 523808China

Zigzag graphene nanoribbons(ZGNRs)with spin-polarized edge states have potential applications in carbon-based *** electronic structure of ZGNRs can be effectively tuned by different widths or dopants,which requires delicately designed ***,we report the successful synthesis of ZGNR with a width of eight carbon zigzag lines and nitrogen-boronnitrogen(NBN)motifs decorated along the zigzag edges(NBN-8-ZGNR)on Au(111)surface,which starts from a specially designed U-shaped monomer with preinstalled NBN units at the zigzag ***-bond-resolved non-contact atomic force microscopy(nc-AFM)imaging confirms the zigzag-terminated edges and the existence of NBN *** electronic states distributed along the zigzag edges have been revealed after a silicon-layer intercalation at the interface of NBN-8-ZGNR and Au(111).Our work enriches the ZGNR family with a new dopant and larger width,which provides more candidates for future carbonbased nanoelectronic and spintronic applications.

关键词： zigzag graphene nanoribbons nitrogen-boron-nitrogen(NBN)dopant edge states scanning tunneling microscopy(STM) non-contact atomic force microscopy(nc-AFM) density functional theory(DFT)calculations

Synthesis of Donor-Acceptorπ-Conjugated Macrocycles by Post-Functionalization

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Chinese Journal of Chemistry 2021年第10期39卷 2705-2710页

作者： Junting Wang Qingyun Wan junzhi liu Department of Chemistry and State Key Laboratory of Synthetic Chemistry The University of Hong KongPokfulam RoadHong KongChina

Main observation and conclusion In this paper,two novel donor-acceptor(D-A)macrocyclic compounds 5 and 7 were successfully synthesized by post-functionalization of a planar dimer macrocycle(1)and a highly twisted trimer macrocycle(2),respectively,via controllable oxidation of methoxy groups and condensation between diketones and phenylenediamine in *** with unembellished 9,10-dimethoxyphenanthrene,the resultant dibenzo[a,c]phenazine motif is electron-deficient rather than electron-rich,yielding two D-Aπ-conjugated macrocycles with more contractive energy *** functional theory(DFT)calculations further support the unequivocal evidence of the D-A properties of macrocycles 5 and *** difference of their photophysical properties was investigated by the aid of ultraviolet-visible absorption and fluorescence ***,the stacking patterns of 7 and its contrastπ-conjugated macrocycle trimer(2)were compared via the analysis of X-ray single crystal,in which the electron-deficient dibenzo[a,c]phenazine unit provides extra interaction sites,resulting in orderly arrangement of 7 in the solid state.

关键词： Macrocycles Post-functionalization Donor-acceptor systems Oxidation Stacking interactions

虚拟空间矢量调制的NPC型三电平并网逆变器预测控制

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河南师范大学学报（自然科学版） 2022年第6期50卷 114-120页

作者：刘俊志黄景涛杨清刘帅河南科技大学电气工程学院河南洛阳471023

针对传统有限集模型预测控制算法遍历寻优计算量大的问题,提出一种应用于NPC型三相三电平并网逆变器的改进型模型预测控制方法.在建立NPC型并网逆变器数学模型的基础上,将虚拟空间矢量调制技术和有限集模型预测控制算法结合,根据中点电... 详细信息

针对传统有限集模型预测控制算法遍历寻优计算量大的问题,提出一种应用于NPC型三相三电平并网逆变器的改进型模型预测控制方法.在建立NPC型并网逆变器数学模型的基础上,将虚拟空间矢量调制技术和有限集模型预测控制算法结合,根据中点电压平衡控制原理,通过虚拟空间矢量调制技术把27个基本电压矢量重构为19个虚拟电压矢量.在原有扇区划分的基础上,增加新的扇区作为辅助扇区,减少模型预测控制遍历寻优次数,降低系统的运算量.同时根据虚拟空间矢量调制技术实现对NPC型并网逆变器中点电压的控制,在模型预测控制的代价函数中省去了中点电压平衡控制这一项.在搭建的NPC型三相三电平并网逆变器系统模型上进行仿真分析,结果表明所提算法能够有效减少计算量,有效实现了中点电压平衡,系统动态性能和稳态性能均有提高.

关键词：并网逆变器有限集模型预测控制虚拟空间矢量调制中点电压平衡

A pathological joint-liver axis mediated by matrikine-activated CD4^(+)T cells

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Signal Transduction and Targeted Therapy 2024年第6期9卷 2679-2693页

作者： junzhi Yi Hui Zhang Fangyuan Bao Zhichu Chen Yuliang Zhong Tianning Ye Xuri Chen Jingyi Qian Mengya Tian Min Zhu Zhi Peng Zongyou Pan Jianyou Li Zihao Hu Weiliang Shen Jiaqi Xu Xianzhu Zhang Youzhi Cai Mengjie Wu Hua liu Jing Zhou Hongwei Ouyang Department of Sports Medicine of the Second Affiliated Hospital and Liangzhu LaboratoryZhejiang University School of MedicineHangzhouChina Dr.Li Dak Sum&Yip Yio Chin Center for Stem Cells and Regenerative Medicine Zhejiang University School of MedicineHangzhouChina Stomatology Hospital School of StomatologyZhejiang University School of MedicineZhejiang Provincial Clinical Research Center for Oral DiseasesHangzhouChina The MOE Key Laboratory of Biosystems Homeostasis&Protection The Key Laboratory of Cancer Molecular Cell Biology of Zhejiang ProvinceLife Sciences InstituteZhejiang UniversityHangzhouChina Department of Orthopedics Huzhou Central HospitalAffiliated Huzhou HospitalZhejiang University School of MedicineHuzhouChina China Orthopedic Regenerative Medicine Group(CORMed) HangzhouChina Department of Orthopedics The First Affiliated HospitalZhejiang University School of MedicineHangzhouChina

The knee joint has long been considered a closed *** pathological effects of joint diseases on distant organs have not been ***,our clinical data showed that post-traumatic joint damage,combined with joint bleeding(hemarthrosis),exhibits a worse liver function compared with healthy *** mouse model,hemarthrosis induces both cartilage degeneration and remote liver ***,we found that hemarthrosis induces the upregulation in ratio and differentiation towards Th17 cells of CD4^(+)T cells in peripheral blood and *** of CD4^(+)T cells reverses hemarthrosis-induced liver *** of cartilage matrix induced by hemarthrosis upregulates serological type Ⅱ collagen(COL Ⅱ),which activates CD4^(+)T *** application of a COL Ⅱ antibody blocks the ***,bulk RNAseq and single-cell qPCR analysis revealed that the cartilage Akt pathway is inhibited by blood ***-articular application of Akt activator blocks the cartilage degeneration and thus protects against the liver impairment in mouse and pig *** together,our study revealed a pathological joint-liver axis mediated by matrikine-activated CD4^(+)T cells,which refreshes the organ-crosstalk axis and provides a new treatment target for hemarthrosis-related disease.

关键词： degeneration damage inhibited