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PFAS in PMs might be the escalating hazard to the lung health

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Nano Research 2023年第12期16卷 13113-13133页

作者： Yue Pan Jie Mei Jipeng Jiang Ke Xu xinglong gao Shasha Jiang Ying Liu Henan Institute of Advanced Technology Zhengzhou UniversityZhengzhou 450052China CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Department of Thoracic Surgery the First Medical Center of Chinese PLA General HospitalBeijing 100853China

Atmospheric particulate matter(PM)is a dominant source of air pollution,in particular,molecules less than 2.5μm in diameter,endangering human *** estimated 2.1 million deaths from exposure to PM2.5 and 700,000 cases of respiratory disease caused by atmospheric pollution were reported on an annual *** main components of PM2.5 include heavy metal elements,water-soluble ions,carbon aerosols,ozone,and organic ***-and polyfluoroalkyl substances(PFASs)are a large group of representative pollutants among the organic compounds absorbed in *** are widely used in industrial production and hardly degraded in the environment,resulting in their accumulation in water,food,and air,and abosorbed by humans via ingestion and *** the other hand,accumulation of PFAS in the human body is proving to be associated with some unfavorable health outcomes,whereas the mechanisms underlying the effects of PFAS exposure on human lung diseases remain unclear at *** toxicological effects of organic components are a significant focus of *** review will fix our attention on the changes in the distribution,composition,and content of PFAS in PM2.5 by location and year,and provide an overview on the influence of PM2.5 and PFAS on lung health,with indications of possible synergistic adverse effects of PM2.5 and PFAS on pulmonary homeostasis.

关键词： PM2.5 per-and polyfluorinated alkyl substances(PFASs) lung pulmonary homeostasis environment pollution

Study on Acoustically Transparent Test Section of Aeroacoustic Wind Tunnel

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Journal of Applied Mathematics and Physics 2018年第1期6卷 1-10页

作者： Jinlei Lv Ning Wang Daxiong Liao Yongsheng Yu xinglong gao State Key Laboratory of Aerodynamics China Aerodynamics Research and Development Center Mianyang China Facility Design and Instrumentation Institute China Aerodynamics Research and Development Center Mianyang China

On the purpose of accurate data acquisition for the aeroacoustic testing mostly in open jet test section of aeroacoustic wind tunnel, the large scale anechoic chamber is specifically designed to build the low background noise environment. A newly acoustic test section is presented in this paper, of which the contour is similar as the closed test section, and the wall is fabricated by the fiber fabric, both the characteristics of closed and open jet test section of conventional wind tunnel are combined in it. By thoroughly researching on the acoustics and aerodynamics of this acoustically transparent test section, significant progress in reducing the background noises in test section and improving the ratio of energy of the wind tunnel and some other aspects have been achieved. Acoustically transparent test section behaves better in acoustics and aerodynamics than conventional acoustic test section because of their high definition in detecting the sound sources and great performance in transmitting sounds.

关键词： Aeroacoustic Experiment Sound Transparent Property Acoustic Test Section Low Background Noise Sound Identification

Acoustic characteristics of stop consonants in fluent reading Chinese Putonghua speech of adult stutterers

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Chinese Journal of Acoustics 2013年第3期32卷 298-308页

作者： FENG Yongqiang YAN Qian gao xinglong PAN Fuping XING Lili LIN Chunlan PAN Jielin Key Laboratory of Speech Acoustics and Content Understanding Institute of AcousticsChinese Academy of Sciences Lin's Speech Training Center

This study investigated whether adults who stutter and normal adult speakers differ in the production of stop consonants in fluent reading Chinese Putonghua *** onset time（VOT） was measured and the spectral moments at the stop burst were calculated for the stutterers（both before and after the speech therapy） and also for the nonstutterers. The statistical results showed that there were no significant differences in VOT between the nonstutterers and stutterers either prior to or after therapy,although the mean VOT of the stutterers was slightly greater than that of the *** results also indicated that both the obstruction place and the subsequent syllabic final exhibited an influence to a greater extent on VOT for the *** the spectral domain,the spectral mean of the stuttering participants before therapy was significantly different from that of the normal participants, whereas the group difference became insignificant after the therapy *** smaller spectral mean for the stutterers might be interpreted as a more posterior occlusion in the oral cavity when producing alveolars and *** addition,productions of the stutterers scattered with a wider range in the space of spectral ***,the smaller main effect of syllabic finals on the mean spectral frequency of the burst suggested that the stutterers exhibited weaker anticipatory coarticulation than the nonstutterers.

关键词： Acoustic characteristics of stop consonants in fluent reading Chinese Putonghua speech of adult stutterers VOT

A forced alignment approach to detect Chinese repetitive stuttering

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Chinese Journal of Acoustics 2013年第3期32卷 309-321页

作者： ZHANG Junbo YAN Qian gao xinglong PAN Fuping FENG Yongqiang XING Lili LIN Chunlan PAN Jielin Key Laboratory of Speech Acoustics and Content Understanding Institute of AcousticsChinese Academy of Sciences Lin's Speech Training Center

A forced alignment based algorithms to detect Chinese repetitive stuttering is studied. According to the features of repetitions in Chinese stuttered speech,improvement solutions are provided based on the previous research ***,a multi-span looping forced alignment decoding networks is designed to detect multi-syllable repetitions in Chinese stuttered ***,branch penalty factor is added in the networks to adjust decoding trend using recursive search in order to reduce the error from the complexity of the decoding networks. Finally,we re-judge the detected stutters by calculating confidence to improve the reliability of the detection *** experimental results show that compared to previous algorithm,the proposed algorithm can improve system performance significantly,about 18%average detection error rate relatively.

关键词： A forced alignment approach to detect Chinese repetitive stuttering than Phone

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无限质量降落伞充气动力学数值模拟

国防科技大学学报 2017年第3期39卷 58-63页

作者：高兴龙张青斌高庆玉唐乾刚国防科技大学航天科学与工程学院湖南长沙410073 中国空气动力研究与发展中心设备设计及测试技术研究所四川绵阳621000

为分析降落伞火星再入环境下的超声速开伞性能,基于任意欧拉-拉格朗日罚函数法和多介质任意拉格朗日欧拉算法,求解可压缩流场与降落伞结构的耦合动力学模型。数值模拟盘缝带伞超声速开伞过程外形变化,预测气动力作用下的伞衣织物三维结... 详细信息

为分析降落伞火星再入环境下的超声速开伞性能,基于任意欧拉-拉格朗日罚函数法和多介质任意拉格朗日欧拉算法,求解可压缩流场与降落伞结构的耦合动力学模型。数值模拟盘缝带伞超声速开伞过程外形变化,预测气动力作用下的伞衣织物三维结构动力学行为。结合风洞试验数据,对比分析降落伞开伞性能和前置体对伞衣充气外形的影响。最终给出超声速伞周围非稳态流场的尾流和激波分布。仿真结果表明:盘缝带伞在超声速开伞过程中被完全充满且充气效果良好,未出现塌陷情况;随着来流马赫数的增加,降落伞阻力系数逐渐减小,充气时间缩短。仿真结果与试验结果保持一致,验证了所提方法的有效性。

关键词：降落伞超声速流动无限质量充气流固耦合可压缩流

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有限质量降落伞充气动力学数值模拟

国防科技大学学报 2016年第4期38卷 185-190页

作者：高兴龙张青斌高庆玉唐乾刚杨涛国防科技大学航天科学与工程学院湖南长沙410073 中国空气动力研究与发展中心设备设计及测试技术研究所四川绵阳621000

为研究空投任务中降落伞有限质量充气过程的动力学行为,基于罚函数耦合方法和网格自适应技术分析了降落伞柔性结构与周围不可压缩流场的流固耦合特性。数值模拟开伞过程伞衣三维外形变化,获得降落伞系统下落速度、阻力面积等参数;对比... 详细信息

为研究空投任务中降落伞有限质量充气过程的动力学行为,基于罚函数耦合方法和网格自适应技术分析了降落伞柔性结构与周围不可压缩流场的流固耦合特性。数值模拟开伞过程伞衣三维外形变化,获得降落伞系统下落速度、阻力面积等参数;对比分析初始投放速度对降落伞开伞时间、伞衣阻力面积的影响;通过试验数据对比分析开伞力变化。计算结果表明,该方法可以有效模拟降落伞系统有限质量充气过程的动力学特性,仿真结果与试验结果相符。

关键词：降落伞流固耦合有限质量充气 ALE动网格

基于红外热成像的电厂输煤廊道火灾识别智能预警识别方法

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信息化研究 2023年第5期49卷 45-50页

作者：高行龙国家能源集团常州发电有限公司常州213033

本文针对当前燃煤电厂输煤廊道内早期火灾隐患难以预警的问题,提出了一种基于红外热成像的输煤廊道火灾智能预警识别方法。通过前景对比分析法对红外热成像探测区域进行温度变化特征提取,并利用温度场过程中的扩散区域不规则性和生长性... 详细信息

本文针对当前燃煤电厂输煤廊道内早期火灾隐患难以预警的问题,提出了一种基于红外热成像的输煤廊道火灾智能预警识别方法。通过前景对比分析法对红外热成像探测区域进行温度变化特征提取,并利用温度场过程中的扩散区域不规则性和生长性,对温度场扩散速率的准确识别,依据温度变化和温度场扩散速率的变化异常,实现火灾早期预警判别。利用某电厂现场获取的红外热成像数据进行了实验验证,结果表明,相比于常规的设定异常温度的识别算法,本文提出的早期火灾识别算法显著提高了检测的稳定性,并有效降低了监控系统的误报和漏报率。

关键词：输煤廊道红外热成像火灾实时预警

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真空管道磁悬浮列车流固耦合特性研究

真空科学与技术学报 2024年第7期44卷 592-600页

作者：寇杰高兴龙李松符澄中国空气动力研究与发展中心设备设计与测试技术研究所绵阳621000

真空管道磁悬浮列车运动与管道内流场相互作用,导致列车流场环境具有高度的非稳定性,同时列车悬浮运行的特性将使列车与管道内流场间存在严重的流固耦合效应。针对这一问题,提出了真空管道磁悬浮列车流固耦合动力学理论,并建立了可以实... 详细信息

真空管道磁悬浮列车运动与管道内流场相互作用,导致列车流场环境具有高度的非稳定性,同时列车悬浮运行的特性将使列车与管道内流场间存在严重的流固耦合效应。针对这一问题,提出了真空管道磁悬浮列车流固耦合动力学理论,并建立了可以实现列车在线实时交互数据的流固耦合数值计算模型,分析真空管道磁悬浮列车的车辆流固耦合特性。研究发现,列车悬浮运行列车尾部流场较为复杂,存在多道斜激波和反射波,随着列车的运行相对较为稳定,而列车顶部和头部的波系相对更加简单,但会随着列车运行发生明显的变化。列车受到的气动载荷呈低频周期性变化,悬浮刚度的减小会导致列车受到的气动载荷幅值增加,频率下降。在30 kN悬浮刚度下,列车的位移和转动幅值可以达到270 mm和14 mrad,并且随着时间推移,列车受到的气动载荷呈现振荡幅值还有增大的态势,影响列车运行安全。上述研究可以为真空管道磁悬浮列车的研究提供理论指导和分析方法参考。

关键词：真空管道磁悬浮列车流固耦合气动载荷气动特性

真空管道列车流固耦合研究进展及关键技术分析

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实验流体力学 2023年第3期37卷 37-49页

作者：寇杰符澄高兴龙孙运强中国空气动力研究与发展中心设备设计与测试技术研究所绵阳621000

利用磁悬浮技术、管道内抽真空形成低压运行环境,真空管道列车理论上可以实现超过1000 km/h的运行速度。封闭管道导致气动环境复杂,同时列车悬浮运行使列车运行姿态极易发生改变,列车流固耦合效应明显。为探究真空管道列车流固耦合理论... 详细信息

利用磁悬浮技术、管道内抽真空形成低压运行环境,真空管道列车理论上可以实现超过1000 km/h的运行速度。封闭管道导致气动环境复杂,同时列车悬浮运行使列车运行姿态极易发生改变,列车流固耦合效应明显。为探究真空管道列车流固耦合理论及分析方法,对真空管道列车气动研究进展、轨道列车流固耦合特性研究进展进行了综述,分析了真空管道列车流固耦合关键技术,提出了需要重点发展的真空管道列车流场分析技术、流固耦合分析技术和控制技术,可为真空管道列车流固耦合机理研究提供参考。

关键词：真空管道列车流固耦合激波气动载荷动力学特性