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Vertical distributions of wintertime atmospheric nitrogenous compounds and the corresponding OH radicals production in Leshan, southwest china

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Journal of Environmental Sciences 2021年第7期33卷 44-55页

作者： Chengzhi Xing Cheng Liu Qihou hu Qingyan Fu Shanshan wang hua Lin Yizhi Zhu Shuntian wang Weiwei wang Zeeshan Javed Xiangguang Ji Jianguo Liu Key Lab of Environmental Optics&Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Department of precision Machinery and precision Instrumentation University of Science and Technology of ChinaHefei 230026China Center for Excellence in regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Laboratory of precision Scientific Instrumentation of Anhui Higher Education Institutes University of Science and Technology of ChinaHefei 230026China Anhui province Key Laboratory of polar Environment and Global Change USTCHefei 230026China shanghai Key Laboratory of Atmospheric particle pollution and prevention(LAp3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200433China shanghai Institute of Eco-Chongming(SIEC) No.3663 Northern Zhongshan RoadShanghai 200062China school of Environmental Science and Optoelectronic Technology University of Science and Technology of ChinaHefei 230026China Chongqing Key Laboratory of Catalysis and New Environmental Materials College of Environment and ResourcesChongqing Technology and Business UniversityChongqing 400067China shanghai Environmental Monitoring Center Shanghai 200235China school of Environmental Science and engineering Nanjing University of Information Science and TechnologyNanjing 210044China

Ground-based multi-axis differential optical absorption spectroscopy(MAX-DOAS)observations were operated from 02 to 21 December 2018 in Leshan,southwest china,to measure HONO,NO_(2) and aerosol extinction vertical distributions,and these were the first MAX-DOAS measurement results in Sichuan *** the measurement period,characteristic ranges for surface concentration were found to be 0.26-4.58 km^(−1) and averaged at 0.93 km^(−1) for aerosol extinction,0.49 to 35.2 ppb and averaged at 4.57 ppb for NO_(2) and 0.03 to 7.38 ppb and averaged at 1.05 ppb for ***,vertical profiles of aerosol,NO_(2) and HONO were retrieved from MAX-DOAS measurements using the Heidelberg profile(HEIprO)*** analysing the vertical gradients of pollutants and meteorological information,we found that aerosol and HONO are strongly localised,while NO_(2) is mainly transmitted from the north direction(city center direction).nitrogen oxides such as HONO and NO_(2) are important for the production of hydroxyl radical(OH)and oxidative capacity in the *** this study,the averaged value of OH production rate from HONO is about 0.63 ppb/hr and maximum value of ratio between OH production from HONO and from(HONO+O_(3))is>93%before12:00 in *** addition,combustion emission contributes to 26%for the source of HONO in Leshan,and we found that more NO_(2) being converted to HONO under the conditions with high aerosol extinction coefficient and high relative humidity is also a dominant factor for the secondary produce of HONO.

关键词： MAX-DOAS Verticle distribution HONO Hydroxyl radical Secondary source

单向复合材料均质化弹性性能预测的集成学习模型:基于SHAp方法的可解释性分析

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Acta Mechanica Sinica 2024年第3期40卷 109-122页

作者：王文照赵云妹李岩 school of aerospace engineering and applied mechanics Tongji UniversityShanghai 200092China

本研究提出了一种可解释的集成学习(EML)数据驱动方法,用于快速预测单向纤维增强复合材料的均质化弹性性能.我们选择了三种机器学习模型――随机森林(rF)、极端梯度提升机(XGboost)和轻量梯度提升机(LGBM)来构建EML模型.基于实验并建立... 详细信息

本研究提出了一种可解释的集成学习(EML)数据驱动方法,用于快速预测单向纤维增强复合材料的均质化弹性性能.我们选择了三种机器学习模型――随机森林(rF)、极端梯度提升机(XGboost)和轻量梯度提升机(LGBM)来构建EML模型.基于实验并建立微观纤维分布的概率统计模型,结合有限元仿真,建立了反映纤维随机分布特征的代表性体元(rVE)模型,并创建相关数据集.通过准确性、效率、可解释性和泛化性等指标对EML模型的性能进行了全面评估,研究结果表明:(1)EML模型有效提升了基机器学习模型的预测精度(r2=0.962,MS E=5.41);(2)我们使用基于合作博弈理论的SHAp可解释性方法对预测结果进行了分析,其中,全局解释发现纤维的体积含量是影响复合材料均质化弹性性能的决定性变量,而局部解释阐明了输入特征对预测结果的关键影响机制;(3)EML模型在实验数据上表现出良好的泛化能力,计算结果与实验数据吻合度高,实现了复合材料均质化弹性性能的高效精准预测.

关键词： Composite materials Homogenization Ensemble learning Interpretation Model generalization

Interference of a Narrowband Biphoton with Double Electromagnetically Induced Transparency in an N-Type System

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Chinese physics Letters 2012年第4期29卷 75-78页

作者： CHEN peng QIAN Jun CHEN Dong-Yuan hu Zheng-Feng wang Yu-Zhu Key Laboratory for Quantum Optics Center for Cold Atom PhysicsShanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800 robert r.McCormick school of engineering and applied Science Northwestern UniversityEvanstonIllinois 60208USA

We predict the possibility of the interference of narrow-band biphotons generated by spontaneous four-wave mixing with double electromagnetically induced transparency configuration in cold *** an N-type fourlevel system,an auxiliary optical field Ωm can create double transparency windows for anti-Stokes *** the slow light effects in the double transparency windows are very strong,two four-wave mixing channels could exist due to the splitting of the phase matching *** biphoton generated from the two four-wave mixing channels can cause interference and shows rabi oscillations in two-photon *** interference mechanism will complement the understanding of interference at the two-photon level.

关键词： transparency mixing photon

EXpErIMENTAL ANALYSIS OF A SAND TAMpED EXpLOSION VESSEL

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EXPERIMENTAL ANALYSIS OF A SAND TAMPED EXPLOSION VESSEL

pandaX: a liquid xenon dark matter experiment at CJpL

The 7th International Conference on Shock and Impact Loads on Structures

作者： Yunxiao Cui~*,Northwest Institute of Nuclear Technology,china Yongle hu,Northwest Institute of Nuclear Technology,china Wanpeng wang,Northwest Institute of Nuclear Technology,china Fengchao wang,Northwest Institute of Nuclear Technology,china

Influence of tamped sand on blast wave in an explosion containment vessel has been studied in this *** buffer material in explosion containment vessel can attenuate shock wave and peak pressure,refrain the strain growth and self-oscillation of explosion containment ***,due to the non-linear dissipation mechanism and heterogeneous properties of buffer material-sand,the attenuation exhibits some abnormal behavior that is the enhancement of shock *** order to analyze this problem,a series of experiments were carried out. both air and sand were filled in the experiments for evaluation of the mitigation *** the experiments of given sand,it is concluded that the attenuation can be achieved if scaled distance is larger than 0.4m/*** this condition,enhancement of blast loading can be *** the purpose of estimation on energy absorption of sand,the compression curve of sand is given by experiment,which also can be useful for numerical calculations.

关键词： mechanics of explosive attenuation shock wave tamped sand explosion containment vessel scaled distance

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Science china(physics,mechanics & Astronomy) 2014年第8期57卷 1476-1494页

作者： CAO XiGuang CHEN Xun CHEN Yunhua CUI XiangYi FANG DeQing FU Changbo GIboni Karl L. GONG HaoWei guo guoDong HE Ming hu Jie huANG XingTao JI XiangDong JU YongLin LI ShaoLi LIN Qing LIU huaXuan LIU JiangLai LIU Xiang LOrENZON Wolfgang MA YuGang MAO YaJun ni KaiXuan pUSHKIN Kirill rEN XiangXiang SChuBNELL Michael SHEN ManBing SHI YuJie STEpHENSON Scott TAN AnDi TArLé Greg wang HongWei wang JiMing wang Meng wang XuMing wang Zhou WEI Yuehuan WU ShiYong XIAO MengJiao XIAO Xiang XIE pengWei YE Tao YOU Yinghui ZEN Xionghui ZHANG hua ZHANG Tao ZHAO HaiYing ZHAO Li ZHOU Xiaopeng Zhu Zhonghua shanghai Institute of applied physics The Institute of Nuclear and particle physics Astronomy and Cosmology (INPAC) and Department of Physics and AstronomyShanghai Jiao Tong University Yalong river Hydropower Development Company Ltd. school of physics and Key Laboratory of particle physics and particle Irradiation (MOE) Shandong University school of physics Peking University Department of physics University of Maryland College Park MD 20742 USA school of Mechanical engineering Shanghai Jiao Tong University Department of physics University of Michigan Ann Arbor MI 48109 USA

pandaX is a large liquid-xenon detector experiment usable for direct dark-matter detection and 136Xe double-beta decay *** central vessel was designed to accommodate a staged target volume increase from initially 120 kg(stage I)to 0.5 t(stage II)and eventually to a multi-ton *** experiment is located in the Jinping Deep-Underground Laboratory in Sichuan,*** detector operates in dual-phase mode,allowing detection of both prompt scintillation,and ionization charge through proportional *** this paper a detailed description of the stage I detector design and performance as well as results established during the commissioning phase are presented.

关键词： dark matter liquid xenon detector underground experiment time projection chamber

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电机驱动非理想振动系统的索末菲效应

力学学报 2024年第9期56卷 2731-2740页

作者：丁川甘子川王笑宋汉文同济大学航空航天与力学学院上海200092

真实转子系统的电机输出功率有限且无法提供理想恒定驱动,随着电机输入电压升高,在系统固有频率附近会出现长时间平均转速停滞和多稳态跳跃,称为“索末菲(Sommerfeld)效应”.这类非理想电机启动时会经过索末菲效应作用区,而长期陷于这... 详细信息

真实转子系统的电机输出功率有限且无法提供理想恒定驱动,随着电机输入电压升高,在系统固有频率附近会出现长时间平均转速停滞和多稳态跳跃,称为“索末菲(Sommerfeld)效应”.这类非理想电机启动时会经过索末菲效应作用区,而长期陷于这一区域时电机转速剧烈波动,会严重影响电机寿命.简化忽略转速波动而注重稳态平均转速,无法观察系统内部受力变化,因此借助数值分析研究电机系统与振动系统作用过程.建立了非理想直流电机-质体-不平衡转子系统的机电耦合动力学模型,通过Matlab/Simulink建模,分析了振动系统各内力分量的变化规律,考察了索末菲效应产生、演变和消失过程.观察到非理想系统进入共振区后,恢复力、惯性力和阻尼力将突然产生偶数倍频成份,导致系统在平均转速与固有频率渐进一致的前提下,产生快转、停转乃至反转剧烈交替切换的现象,并在输入电压大于临界电压后结束跳跃.研究描述了在非理想驱动下系统展现的非线性行为,最后为振动系统动力设计提供指导并确保动力设备正常运行.

关键词：索末菲效应转子系统振动系统非线性动力学

First dark matter search results from the pandaX-Ⅰ experiment

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Science china(physics,mechanics & Astronomy) 2014年第11期57卷 2024-2030页

作者： XIAO MengJiao XIAO Xiang ZHAO Li CAO XiGuang CHEN Xun CHEN Yunhua CUI XiangYi FANG DeQing FU Changbo GIboni Karl L. GONG HaoWei guo guoDong hu Jie huANG XingTao JI XiangDong JU YongLin LEI SiAo LI ShaoLi LIN Qing LIU huaXuan LIU JiangLai LIU Xiang LOrENZON Wolfgang MA YuGang MAO YaJun ni KaiXuan pUSHKIN Kirill rEN XiangXiang SChuBNELL Michael SHEN ManBing STEpHENSON Scott TAN AnDi TArL Greg wang HongWei wang JiMin wang Meng wang XuMing wang Zhou WEI Yuehuan WU ShiYong XIE pengWei YOU Yinghui ZENG Xionghui ZHANG hua ZHANG Tao Zhu Zhonghua The Institute of Nuclear and particle physics Astronomy and Cosmology (INPAC) and Department of Physics and AstronomyShanghai Jiao Tong University shanghai Institute of applied physics Chinese Academy of Sciences Yalong river Hydropower Development Company Ltd. school of physics and Key Laboratory of particle physics and particle Irradiation (MOE) Shandong University school of physics Peking University Department of physics University of MarylandCollege ParkMD20742USA school of Mechanical engineering Shanghai Jiao Tong University Department of physics University of MichiganAnn ArborMI48109USA

We report on the first dark-matter(DM)search results from pandaX-I,a low threshold dual-phase xenon experiment operating at the china Jinping Underground *** the 37-kg liquid xenon target with 17.4 live-days of exposure,no DM particle candidate event was *** result sets a stringent limit for low-mass DM particles and disfavors the interpretation of previously-reported positive experimental *** minimum upper limit,3.7×10-44cm2,for the spin-independent isoscalar DM-particle-nucleon scattering cross section is obtained at a DM-particle mass of 49 GeV/c2at 90%confidence level.

关键词： dark matter direct detection xenon

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基于径向基函数的冷却塔风场重构

工程力学 2019年第5期36卷 226-234页

作者：李维勃王国砚钱志浩王昊同济大学航空航天与力学学院上海200092

采用径向基函数法根据风洞试验结果对冷却塔的塔筒外表面进行风场重构,比较了重构前后喉部高度处迎风点和背风点的时程风压系数的相对误差,得出当体型常数C=0.5 C_(max)时(C_(max)为C值的最大取值),在整个采样时间内绝大多数时程风压系... 详细信息

采用径向基函数法根据风洞试验结果对冷却塔的塔筒外表面进行风场重构,比较了重构前后喉部高度处迎风点和背风点的时程风压系数的相对误差,得出当体型常数C=0.5 C_(max)时(C_(max)为C值的最大取值),在整个采样时间内绝大多数时程风压系数的相对误差在5%以内;将若干子午线上和环线上的重构结果与刚性模型测压风洞试验结果进行对比,证明了重构前后风压系数分布一致;分析了径向基函数中3种不同的C值对重构风场的影响,得出在这3种C值重构的结果中,取C=0.5 C_(max)时重构的效果最好;最后比较了两种不同点集密度重构风场的风场特性,得出加密前后风场特性不变的结果,为优化后续的结构瞬态动力响应分析提供了依据。该文研究表明,基于径向基函数法进行冷却塔风场重构是一种简单、有效的方法。

关键词：冷却塔结构风场重构径向基函数风洞试验风荷载时程

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岩石化学风化力学特性的宏微观定量关联

同济大学学报（自然科学版） 2024年第6期52卷 911-919页

作者：周志豪王华宁蒋明镜同济大学土木工程学院上海200092 同济大学航空航天与力学学院上海200092 同济大学土木工程防灾国家重点实验室上海200092 苏州科技大学土木工程学院江苏苏州215009

为了分析化学风化对岩石力学性能的影响机制,采用密集排列的颗粒集合体模拟岩石材料,将与化学风化时间相关的质量损失率引入颗粒刚度和胶结模型。基于均匀化方法和格构模型,推导获得了风化岩石弹性阶段应力‒应变关系和强度准则以及宏观... 详细信息

为了分析化学风化对岩石力学性能的影响机制,采用密集排列的颗粒集合体模拟岩石材料,将与化学风化时间相关的质量损失率引入颗粒刚度和胶结模型。基于均匀化方法和格构模型,推导获得了风化岩石弹性阶段应力‒应变关系和强度准则以及宏观弹性和强度参数与微观参数(颗粒接触响应特性、风化损伤参数等)的定量关联,并探究了化学风化及其时效性对岩石力学性能的影响规律。结果表明,随着质量损失率的增大以及反应时间的增加,风化岩石的刚度和强度均呈负指数减小;当环境pH值较低时,岩石的峰值黏聚力和峰值内摩擦角随着反应时间的增大均显著降低;当环境pH值较高时,开始阶段岩石的峰值黏聚力显著降低,而峰值内摩擦角变化不大,峰值内摩擦角的显著降低需要更长的风化时间。

关键词：岩石化学风化宏微观时效效应