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The Probability Density Function Related to Shallow Cumulus Entrainment Rate and Its Influencing Factors in a Large-Eddy Simulation

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Advances in Atmospheric sciences 2024年第1期41卷 173-187页

作者： Lei ZHU Chunsong LU Xiaoqi XU xin HE Junjun LI Shi LUO Yuan WANG fan WANG Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)and Key Laboratory for Aerosol-Cloud-Precipitation of china Meteorological Administration Nanjing University of Information Science and TechnologyNanjing 210044China nanjing Joint institute for Atmospheric sciences Nanjing 210019China College of Aviation Meteorology Civil Aviation Flight University of ChinaGuanghan 618307China Collaborative Innovation Center for Western Ecological Safety Lanzhou UniversityLanzhou 730000China Department of geography Hong Kong Baptist UniversityHong Kong SAR 999077China

The process of entrainment-mixing between cumulus clouds and the ambient air is important for the development of cumulus *** obtaining the entrainment rate(λ)is particularly important for its parameterization within the overall cumulus parameterization *** this study,an improved bulk-plume method is proposed by solving the equations of two conserved variables simultaneously to calculateλof cumulus clouds in a large-eddy *** results demonstrate that the improved bulk-plume method is more reliable than the traditional bulk-plume method,becauseλ,as calculated from the improved method,falls within the range ofλvalues obtained from the traditional method using different conserved *** probability density functions ofλfor all data,different times,and different heights can be well-fitted by a log-normal distribution,which supports the assumed stochastic entrainment process in previous *** analysis demonstrate that the relationship betweenλand the vertical velocity is better than other thermodynamic/dynamical properties;thus,the vertical velocity is recommended as the primary influencing factor for the parameterization ofλin the *** results of this study enhance the theoretical understanding ofλand its influencing factors and shed new light on the development ofλparameterization.

关键词： large-eddy simulation cumulus clouds entrainment rate probability density functions spatial and temporal distribution

10B-doped MCP detector developed for neutron resonance imaging at Back-n white neutron source

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Nuclear Science and Techniques 2024年第8期35卷 58-68页

作者： Qiang Li Li‑Jiao Wang Jing‑Yu Tang Xiang‑Biao Qiu Zhen Chen Mao‑Yuan Zhao Chang‑Jun Ning Kai Pan Wei Xu Tao Li Su‑Peng Lu Han Yi Rui‑Rui fan Chang‑Qing Feng Rong Zhang Xiao‑Yang Sun Qi An Hao‑fan Bai Jiang‑Bo Bai Jie Bao Ping Cao Qi‑Ping Chen Yong‑Hao Chen Zeng‑Qi Cui An‑Chuan fan fan‑Zhen Feng Min‑Hao Gu Chang‑Cai Han Zi‑Jie Han Guo‑Zhu He Yong‑cheng He Yang Hong Yi‑Wei Hu Han‑Xiong Huang Wei Jiang Zhi‑Jie Jiang Zheng‑Yao Jin Ling Kang Bo Li Gong Li Xiao Li Yang Li Jie Liu Rong Liu Shu‑Bin Liu Yi‑Na Liu Guang‑Yuan Luan Jie Ren Zhi‑Zhou Ren Xi‑Chao Ruan Zhao‑Hui Song Kang Sun Zhi‑xin Tan Sheng‑Da Tang Jin‑cheng Wang Peng‑cheng Wang Zhao‑Hui Wang Zhong‑Wei Wen Xiao‑Guang Wu Xuan Wu Cong Xia Yong‑Ji Yu Guo‑Hui Zhang Hang‑Chang Zhang Lin‑Hao Zhang Qi‑Wei Zhang Xian‑Peng Zhang Yu‑Liang Zhang Yue Zhang Zhi‑Yong Zhang Zhi‑Hao Zhou Ke‑Jun Zhu Chong Zou institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China State Key Laboratory of Particle Detection and Electronics Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Dongguan Songshan Lake Future School Dongguan 523808China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China North Night Vision Science and Technology(nanjing)Research institute Co.Ltd Nanjing 211106China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China institute of Modern Physics Fudan UniversityShanghai 200433China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China china academy of Engineering Physics Institute of Nuclear Physics and ChemistryMianyang 621900China USTC archaeometry lab University of Science and Technology of ChinaHefei 230026China Northwest institute of Nuclear Technology Xi’an 710024China University of chinese academy of sciences Beijing 100049China china Shipbuilding Trading Co. LtdBeijing 100044China

Neutron resonance imaging(NRI)has recently emerged as an appealing technique for neutron *** complexity surpasses that of conventional transmission imaging,as it requires a high demand for both a neutron source and ***,the progression of NRI technology has been sluggish since its inception in the 1980s,particularly considering the limited studies analyzing the neutron energy range above *** white neutron source(Back-n)at the china Spallation Neutron Source(CSNS)provides favorable beam conditions for the development of the NRI technique over a wide neutron energy range from eV to ***-sensitive microchannel plates(MCP)have emerged as a cutting-edge tool in the field of neutron detection owing to their high temporal and spatial resolutions,high detection efficiency,and low *** this study,we report the development of a 10B-doped MCP detector,along with its associated electronics,data processing system,and NRI experiments at the *** heavy elements such as gold,silver,tungsten,and indium can be easily identified in the transmission images by their characteristic resonance peaks in the 1–100 eV energy range;the more difficult medium-weight elements such as iron,copper,and aluminum with resonance peaks in the 1–100 keV energy range can also be *** particular,results in the neutron energy range of dozens of keV(Aluminum)are reported here for the first time.

关键词： Neutron resonance imaging 10B doped MCP detector White neutron source Sample nuclide identification

Study of the response of 10B-doped MCP to wide-energy range neutrons from eV to MeV

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Nuclear Science and Techniques 2024年第8期35卷 132-141页

作者： Qiang Li Li‑Jiao Wang Xiang‑Biao Qiu Jing‑Wen Li Wei Xu Tao Li Ze‑Bin Lin Chang‑Jun Ning Yong‑Hao Chen Rui‑Rui fan Kang Sun Jing‑Yu Tang Rong Zhang Han‑Tao Jing Bo Mei Qi An Hao‑fan Bai Jiang‑Bo Bai Jie Bao Ping Cao Qi‑Ping Chen Zhen Chen Zeng‑Qi Cui An‑Chuan fan Chang‑Qing Feng fan‑Zhen Feng Ke‑Qing Gao Min‑Hao Gu Chang‑Cai Han Zi‑Jie Han Guo‑Zhu He Yong‑cheng He Yang Hong Yi‑Wei Hu Han‑Xiong Huang Wei‑Hua Jia Hao‑Yu Jiang Wei Jiang Zhi‑Jie Jiang Zheng‑Yao Jin Ling Kang Bo Li Chao Li Gong Li Jia‑Wen Li Xiao Li Yang Li Jie Liu Rong Liu Shu‑Bin Liu Guang‑Yuan Luan Bin‑Bin Qi Jie Ren Zhi‑Zhou Ren Xi‑Chao Ruan Zhao‑Hui Song Zhi‑xin Tan Sheng‑Da Tang Peng‑cheng Wang Zhao‑Hui Wang Zhong‑Wei Wen Xiao‑Guang Wu Xuan Wu Li‑Kun Xie Yi‑Wei Yang Han Yi Yong‑Ji Yu Guo‑Hui Zhang Lin‑Hao Zhang Mo‑Han Zhang Qi‑Wei Zhang Xian‑Peng Zhang Yu‑Liang Zhang Yue Zhang Zhi‑Yong Zhang Mao‑Yuan Zhao Lu‑Ping Zhou Zhi‑Hao Zhou Ke‑Jun Zhu institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Dongguan Songshan Lake Future School Dongguan 523808China North Night Vision Science&Technology(nanjing)Research institute Co.Ltd. Nanjing 211106China Sino‑French institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China USTC Archaeometry Lab University of Science and Technology of ChinaHefei 230026China Northwest institute of Nuclear Technology Xi’an 710024China University of chinese academy of sciences Beijing 100049China

Neutron-sensitive microchannel plates(nMCPs)have applications in neutron detection,including energy spectrum measurements,neutron-induced cross sections,and neutron imaging.10B-doped MCPs(B-MCPs)have attracted significant attention owing to their potential for exhibiting a high neutron detection efficiency over a large neutron energy *** spatial and temporal resolutions are useful for neutron energy-resolved ***,their practical applications still face many technical *** this study,a B-MCP with 10 mol%10B was tested for its response to wide-energy neutrons from eV to MeV at the Back-n white neutron source at the china Spallation Neutron *** neutron detection efficiency was calibrated at 1 eV,which is approximately 300 times that of an ordinary MCP and indicates the success of 10 B *** factors that caused the reduction in the detection efficiency were simulated and *** neutron energy spectrum obtained using B-MCP was compared with that obtained by other measurement methods,and showed very good consistency for neutron energies below tens of *** response is more complicated at higher neutron energy,at which point the elastic and nonelastic reactions of all nuclides of B-MCP gradually become *** is beneficial for the detection of neutrons,as it compensates for the detection efficiency of B-MCP for high-energy neutrons.

关键词： Neutron radiation image 10B-doped MCP Neutron response Wide-energy range neutrons

Effects of hydrodynamics processes on phosphorus fluxes from sediment in large,shallow Taihu Lake

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Journal of Environmental sciences 2007年第9期19卷 1055-1060页

作者： YOU Ben-sheng ZHONG Ji-cheng fan cheng-xin WANG Tong-cheng ZHANG Lu DING Shi-ming State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China. Graduate University of chinese academy of sciences Beijing 100049 China Jiangsu Provincial academy of Environmental Science Nanjing 210036 China nanjing institute of Environmental sciences State Environmental Protection Administration Nanjing 210042 China

The turnover of phosphorus （P） in lake sediments, a major cause of eutrophication and subsequent deterioration of water quality, is in need of deep understanding. In this study, effects of resuspension on P release were studied in cylindrical microcosms with Yshape apparatus. The results indicated that there was a positive correlation between flux of suspended substance across sediment-water interface （Fss） and the wind speed, and an increasing Fss during each wind process followed by a steady state. The maximal Fss under fight, moderate, and strong wind conditions were 299.9±41.1,573.4±61.7, and 2093.8±215.7 g/m^2, respectively. However, flux of P across sediment-water interface （Fp） did not follow a similar pattern as Fss responding to wind intensity, which increased and reached the maximum in initial 120 rain for fight wind, then decreased gradually, with maximal flux of 9.4±1.9 mg/m^2. A rapid increase of Fp at the first 30 rain was observed under moderate wind, with maximal flux of 11.2±0.6 mg/m^2. Surprisingly, strong wind caused less Fp than under light and moderate wind conditions with maximal flux of 3.5±0.9 mg/m^2. Fss in water column declined obviously during the sedimentation process after winds, but Fp varied with wind regime. No obvious difference was detected on Fp after 8 h sedimentation process, compared with the initial value, which means little redundant P left in the water column after winds.

关键词： hydrodynamic process resuspension sedimentation phosphorus flux Taihu Lake

施氮和增温对鄱阳湖灰化薹草(Carex cinerascens Kukenth.)湿地秋草生长期氧化亚氮排放的影响

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湖泊科学 2024年第4期36卷 1152-1162页

作者：程俊翔徐力刚樊龙凤陈曦游海林中国科学院南京地理与湖泊研究所中国科学院流域地理学重点实验室南京210008 中国科学院南京地理与湖泊研究所鄱阳湖湖泊湿地综合研究站九江332899 江西省生态文明研究院南昌330036 中国科学院大学南京学院南京211135 南京工业大学环境科学与工程学院南京211816 江西省科学院流域生态研究所南昌330096

湿地是地球上十分重要的氮库,而且对大气氮沉降增加、气候变暖等全球变化响应非常敏感。目前关于湿地氧化亚氮(N_(2)O)的研究还存在较大的区域不均衡性,湿地N_(2)O排放对全球变化的响应也具有很大的不确定性。因此,本研究通过在鄱阳湖... 详细信息

湿地是地球上十分重要的氮库,而且对大气氮沉降增加、气候变暖等全球变化响应非常敏感。目前关于湿地氧化亚氮(N_(2)O)的研究还存在较大的区域不均衡性,湿地N_(2)O排放对全球变化的响应也具有很大的不确定性。因此,本研究通过在鄱阳湖灰化薹草(Carex cinerascens Kukenth.)湿地开展N_(2)O通量原位监测及全球变化模拟实验,以揭示鄱阳湖灰化薹草湿地N_(2)O排放变化特征及其对施氮和增温的响应关系。结果表明,鄱阳湖灰化薹草湿地总体上是N_(2)O弱源,平均N_(2)O通量为(5.77±1.45)μg/(m^(2)·h)。施氮对鄱阳湖灰化薹草湿地N_(2)O通量有显著影响,相对于不施氮,施氮可显著提升2.7倍的N_(2)O排放通量。增温及其与施氮的交互作用对N_(2)O通量的影响不显著。鄱阳湖灰化薹草湿地N_(2)O排放过程主要由湿地植物调节,而与空气温度、土壤温度、土壤水分等非生物因素无显著相关关系。研究结果有利于深入认识全球变化与湖泊湿地N_(2)O排放的互馈作用,并为评估全球变化背景下湖泊湿地N_(2)O收支平衡提供重要支撑;未来还需要加强多因子交互作用研究并开展长期连续监测,从而为阐明湿地氮循环对全球变化的响应机制和构建气候预测模型提供验证数据和理论依据。

关键词：鄱阳湖湿地温室气体 N_(2)O 全球变化氮沉降气候变暖

Geochemistry of Iron,Sulfur and Related Heavy Metals in Metal-Polluted Taihu Lake Sediments

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Pedosphere 2008年第5期18卷 564-573页

作者： YIN Hong-Bin fan cheng-xin DING Shi-Ming ZHANG Lu ZHONG Ji-cheng State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology ChineseAcademy of Sciences Nanjing Z10008 （China）. Graduate University of the chinese academy of sciences Beijing 100049 （China）

To understand the geochemical characteristics of iron and sulfur and the extent of iron-sulfide minerals influencing heavy metal behaviour in metal-polluted sediments of Talhu Lake, two sites, in Meiliang Bay （ML） and Wuli Lake （WL）, were selected to study the fractionation of iron, sulfur and related heavy metals. There were relatively high concentrations of Fe^2＋ and low concentrations of total S^2- in porewaters, indicating that conditions in these sediments favored iron reduction. The concentrations of acid volatile sulfides in sediments were 1.9-9.6 μmol g^-1 at ML and 1.0-11.7 μmool g^-1 at WL, both in the range of values detected in unpolluted lakes. Pyrite-S was 10.2-49.4 μmol g^-1 at ML and 10.3- 33.0 μmol g^-1 at WL, accounting for more than 69% of the reduced inorganic sulfur at both sites. The low degree of sulphidization （〈 14%） and pyritization （〈 10%） indicate that sulfate may be the limiting factor for pyrite formation. The extractability of Mn, Cu, Pb, Zn, Ni, and Cr in sediments all suggest that sulfides are not the major binding phase for these metals during early diagenesis. Sulfur may play a modest role in the geochemistry of iron and traced metals in the sediments.

关键词： heavy metals reactive iron reduced inorganic sulfur Taihu Lake

太湖底泥的污染控制及修复技术的可行性应用探讨

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污染防治技术 2004年第3期 23-26页

作者：郑超海范成新逄勇河海大学环境科学与工程学院中国科学院南京地理与湖泊研究所河海大学环境科学与工程学院江苏南京 210098 江苏南京 210008

太湖表层底泥营养物、重金属和有机污染物等含量较高,并有向水体释放倾向,对水体及水生生态系统造成威胁。文章探讨了对太湖已开展或近期可开展的内源污染治理实用和示范技术,如外部污染源控制、原位覆盖、原位底泥氧化、原位上覆水充... 详细信息

太湖表层底泥营养物、重金属和有机污染物等含量较高,并有向水体释放倾向,对水体及水生生态系统造成威胁。文章探讨了对太湖已开展或近期可开展的内源污染治理实用和示范技术,如外部污染源控制、原位覆盖、原位底泥氧化、原位上覆水充氧、生态疏浚、生物修复技术以及自然消减技术等。对上述技术运用于太湖进行了可行性分析。

关键词：太湖沉积物污染控制技术

Influence of Sediment Dredging on Chemical Forms and Release of Phosphorus

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Pedosphere 2008年第1期18卷 34-44页

作者： ZHONG Ji-cheng YOU Ben-Sheng fan cheng-xin LI Bao ZHANG Lu DING Shi-Ming State Key Laboratory of Lake Science and Environment Nanjin9 Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 (China) Graduate School of the chinese academy of sciences Beijin9 100089 (China)

A laboratory experiment was carried out through a six-month incubation of undredged （control） and dredged cores to study the effect of sediment dredging on phosphorus （P） release from the sediment in the Taihu Lake. During the experiment, dredging the upper 30 cm layer could efficiently reduce the interstitial PO4^3-P concentration and different P forms in the sediment. The P fluxes of the undredged and dredged cores ranged from -5.1 to 3047.6 and -60.7 to 14.4μg·m^-2·d^-1, respectively. The fluxes of the dredged cores were generally lower than those of the control. Differences in the fluxes between the dredged and undredged cores were statistically significant （P 〈 0.05） from March to June 2006. The sediment P in the dredged cores had a lower release potential than that in the control. Dredging can be considered as a useful measure for rehabilitating the aquatic ecosystem after the external P loading in the Talhu Lake catchment was efficiently reduced.

关键词： phosphorus forms phosphorous release sediment dredging Taihu Lake

绿色基础设施供需适配关系演进特征及其规律--以南京市为例

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生态学报 2024年第2期44卷 463-475页

作者：赵海霞顾斌杰王俊淇范金鼎李欣中国科学院南京地理与湖泊研究所南京210008 中国科学院大学南京学院南京211135 苏州科技大学环境科学与工程学院苏州215009

绿色基础设施(GI)供需均衡对维护城市或区域生态系统稳定,提升国土空间治理体系和治理能力现代化水平,推动城市高质量发展具有重要意义。从绿色基础设施供需适配关系的视角出发,运用生态系统服务价值法对GI服务供给进行测度,从社会、经... 详细信息

绿色基础设施(GI)供需均衡对维护城市或区域生态系统稳定,提升国土空间治理体系和治理能力现代化水平,推动城市高质量发展具有重要意义。从绿色基础设施供需适配关系的视角出发,运用生态系统服务价值法对GI服务供给进行测度,从社会、经济、生态和环境四方面综合评价GI需求,研究南京市GI供需适配关系的演进情势,揭示其时空配置的差异性。结果表明:(1)2000—2020年,南京市GI供给呈主城低、郊区高的分布格局,总供给、人均供给和单项供给均先减后增。(2)GI总需求逐年减少,形成从中心城区向郊区递减的三个圈层。(3)南京市共划出9个供需适配类型,对应11个辖区划出99个供需适配类型组合区,供需适配较好区与较差区分别占全市国土面积的26%和44%,呈不均衡分布。(4)主城区较适应的匹配类型是低供给-中需求,郊区维持低供给-低需求较符合区域发展实际,并针对不同类型区优化提升提出对策建议。

关键词：绿色基础设施供需测度适配关系空间分异南京市

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