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Advances in Atmospheric Radiation:Theories,Models,and Their Applications.PartⅡ:Radiative Transfer Models and Related Applications

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Journal of Meteorological Research 2024年第2期38卷 183-208页

作者： Hua ZHANG Feng ZHANG Lei liU Yuzhi liU Husi LETU Yuanjian YANG zhengqiang li Kun WU Shuai HU Ming li Tie DAI Fei WANG Zhili WANG Yuxiang liNG Yining SHI Chao liU State Key Laboratory of Severe Weather and Institute of Climate System Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081 Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044 Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai 200438 College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073 College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000 State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100101 School of Atmospheric Physics Nanjing University of Information Science&TechnologyNanjing 210044 School of Atmospheric Sciences Nanjing University of Information Science&TechnologyNanjing 210044 Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029 CMA Earth System Modeling and Prediction Centre China Meteorological Administration(CMA)Beijing 100081

The subject of“atmospheric radiation”includes not only fundamental theories on atmospheric gaseous absorption and the scattering and radiative transfer of particles(molecules,cloud,and aerosols),but also their applications in weather,climate,and atmospheric remote sensing,and is an essential part of the atmospheric sciences.This review includes two parts(Part I and PartⅡ);following the first part on gaseous absorption and particle scattering,this part(PartⅡ)reports the progress that has been made in radiative transfer theories,models,and their common applications,focusing particularly on the contributions from Chinese researchers.The recent achievements on radiative transfer models and methods developed for weather and climate studies and for atmospheric remote sensing are firstly reviewed.Then,the associated applications,such as surface radiation estimation,satellite remote sensing algorithms,radiative parameterization for climate models,and radiative-forcing related climate change studies are summarized,which further reveals the importance of radiative transfer theories and models.

关键词： atmospheric radiation radiative transfer remote sensing radiative forcing climate change

A satellite-derived,ground-measurement-independent monthly PM_(2.5)mass concentration dataset over China during 2000-2015

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Big Earth Data 2022年第4期6卷 633-649页

作者： Ying Zhang zhengqiang li Yuanyuan Wei Zongren Peng State Environmental Protection Key Laboratory of Satellite Remote Sensing Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina

Following the accelerated development of urbanization and industrialization,atmospheric particulate matter has become a significant threat to public health globally.Environmental health studies usually use the mass concentration of fine particles(PM_(2.5))as a base data to predict the health risks of particulate exposure.However,PM_(2.5)data from ground monitoring stations in China has not been provided until January 2013 by the Ministry of Environmental Protection of China.Hence,an alternative dataset of PM_(2.5)spatiotemporal distributions extending to years earlier than 2013 is urgently needed,which is of great significance to atmospheric environment assessment and pollution prevention and control.Atmospheric aerosol products by the moderate-resolution imaging spectroradiometer(MODIS)have been released since 2000,which provides the possibility to reconstruct historical PM_(2.5).However,most current methods do not have the ability to estimate PM_(2.5)mass concentration independently of ground observations.The PM_(2.5)mass concentration data set produced by PM_(2.5)remote sensing(PMRS)model based on physical processes does not depend on the ground observations,and also is not affected by the uncertainty of model emission sources or the completeness of chemical reaction mechanism.These ensure that the point-by-point validation for PM_(2.5)mass concentration data is more convincing,and the dataset can also be further used for model assimilation and artificial intelligence training to improve their predictions.In this study,we calculate the monthly PM_(2.5)mass concentration near the ground over land of China using aerosol inversion products(aerosol optical depth and fine-mode fraction)of MODIS and meteorological data(boundary layer height&relative humidity)provided by the Modern-Era Retrospective Analysis for Research and Applications Version 2(MERRA-2)data set.The results show that,in China,6 pollution centers mainly concentrated in the central and eastern regions.The highest PM_(2.5)mass concentration occurred i

关键词： PM_(2.5) data set satellitederived China monthly

Hot-melt extrusion promotes dissolution,extends“spring-parachute”process and inhibits crystallization in supersaturating microparticle systems

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Particuology 2023年第7期78卷 35-48页

作者： Yanfei Zhang Huifeng Zhang Huan Yu Yinghui Ma Chengyi Hao Xiaoying lin Yong Zhang zhengqiang li Xianrong Qi Jia Zeng Nianqiu Shi School of Pharmacy jilin Medical University Jilin132013jilin ProvinceChina Collge of life Science Jilin UniversityChangchun130012jilin ProvinceChina Department of Pharmaceutics School of Pharmaceutical SciencePeking UniversityBeijing100191China College of Pharmaceutical Sciences Yanbian UniversityYanji133002jilin ProvinceChina

Despite the potential advantages of amorphism-induced supersaturation,the merit of new amorphiza-tion formation methods on the properties of the amorphous drug including the stability of the amor-phous state,dissolution/solubility,supersaturation,and"spring-parachute"process is still poorly understood,particularly for certain amorphous supersaturating drug delivery systems(aSDDS).The present work aimed to explore the detailed merit of current attractive amorphization manufacturing methods(i.g.,hot-melt extrusion(HME)technique)on the property improvement of aSDDS in form of amorphous solid dispersion microparticles by employing a model Bcs II drug nitrendipine and a polyvinylpyrrolidone-based model polymer copovidone.Many asDDS systems were developed by various methods,and their physicochemical properties were characterized by SEM,PXRD and DSC.HME-triggered amorphization induced superior supersaturation by the observation of the highest dissolution and solubility.HME induced the optimal supersaturation duration by the observed greatest extension of"spring-parachute"process(e.g,maximum AUCspring-parachute).HME technique is comparable with other techniques for the stabilization of amorphous state during storage.All aSDDS systems by HME and other methods showed improved long-term stability of the amorphous state in comparison to the pure amorphous drug.Fourier transformation infrared spectroscopy,Noyes-Whitney equation,nucleation theory and Gibbs free energy of transfer(△G)were used to analyze the underlying mechanisms.Mo-lecular mechanism studies indicated that HME caused a stronger crystallization inhibition effect in the asDDS systems than other methods,but molecular interaction is not a dominant mechanism for property enhancement caused by HME.For the mechanism associated with the polymer itself(PVPVA64),it could inhibit the drug recrystallization,solubilize the drug spontaneously and cause the improved molecular interactions in all aSDDS systems.This study provided a deep insight into detailed advantage of HME-t

关键词： Hot-melt extrusion-triggered amorphization Extensionof"spring-parachute"process Promotion of dissolution/solubility Inhibition of crystallization from a supersaturated state Amorphism-based supersaturating drug microparticle systems

中国大宗商品价格与龙头企业股价的联动关系——来自期货波动溢出的收敛加速效应

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国际商务(对外经济贸易大学学报) 2024年第3期 95-115页

作者：李正强金缦对外经济贸易大学国际经济贸易学院巢湖学院经济与法学学院

本文通过对中国大宗商品期货市场、现货市场和相关龙头企业股票市场2012—2021年波动聚集效应的实证研究,发现在控制宏观经济因素下,现货市场的价格波动在统计意义上不存在对期货市场和股票市场的传导,而期货市场价格的波动会单向传导... 详细信息

本文通过对中国大宗商品期货市场、现货市场和相关龙头企业股票市场2012—2021年波动聚集效应的实证研究,发现在控制宏观经济因素下,现货市场的价格波动在统计意义上不存在对期货市场和股票市场的传导,而期货市场价格的波动会单向传导至上游和下游龙头企业的股票市场,形成短期信息价值,并通过波动聚集,加速商品价格的收敛。通过特殊事件的断点检验,研究发现在国际现货和(或)期货价格剧烈波动的情况下,期货工具的使用会显著产生波动聚集,加速商品价格对市场冲击的收敛速度,降低大宗商品价格波动对龙头企业长期经营的影响。本文研究结论为有效发挥期货市场的避险功能提供了理论支持。

关键词：大宗商品价格波动波动溢出效应波动聚集

Unique fluorescence properties of a self-assembling bis-pyrene molecule

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Chinese Chemical Letters 2018年第11期29卷 1645-1647页

作者： Zhaozhong li Yang li Dong Wang Qing Cui zhengqiang li Lei Wang Huai Yang Department of Materials Physics and Chemistry School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China National Center for Nanoscience and Technology (NCNST) Beijing 100190 China Department of Materials Science and Engineering College of Engineering Peking University Beijing 100871 China

A self-assembling bis-pyrene （BP） molecule with π-π interactions was designed and synthesized. In condensed state, the BP self-assembled into highly-ordered mesophase at room temperature, which was characterized by using differential scanning calorimetry （DSC）, polarized optical microscope （POM）, and 1 D wide angle X-ray diffraction （WAXD） techniques. In solution, the BP self-assembled into nanoflbers in the mixed dichloromethane and hexane （1：1 volume ratio） solvent. Interestingly, the BP was not fluorescent when dissolved in dichloromethane solution. However, the self-assembled nanostructures of BP in the mixed solvent showed high intensity of green fluorescence. The advantages of self-assembly and fluorescence feature exhibited that BP could be promising fluorescence nanoprobes or nanosensors for various applications.

关键词： Bis-pyrene Fluorescence Self-assembly Mesophase π-π Interaction

密封泡菜母水的真菌群落动态及与理化因子的相关性

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微生物学通报 2024年第5期51卷 1676-1689页

作者：安睿邓巍李政强李静超杨晓燕大理大学东喜玛拉雅研究院云南大理671003 大理大学三江并流区域生物多样性保护与利用云南省创新团队云南大理671003 中国三江并流区域生物多样性协同创新中心云南大理671003

【背景】真菌对泡菜的风味与质地发挥着重要作用,影响泡菜及母水的储存时长。母水泡菜是我国的传统泡菜制作方法,也是保持泡菜原有风味的核心技术。【目的】解析密闭储存泡菜母水的真菌群落动态及与理化因子的关系。【方法】采用扩增子... 详细信息

【背景】真菌对泡菜的风味与质地发挥着重要作用,影响泡菜及母水的储存时长。母水泡菜是我国的传统泡菜制作方法,也是保持泡菜原有风味的核心技术。【目的】解析密闭储存泡菜母水的真菌群落动态及与理化因子的关系。【方法】采用扩增子序列变体(amplicon sequence variants,ASV)技术监测25℃密闭储存30 d内泡菜母水中真菌群落的动态变化,应用流动分析仪监测母水的理化因子变化。【结果】结合泡菜母水真菌群落动态及理化因子变化,真菌群落演替在30 d内可划分为3个时期(前期为1–5 d,中期为6–16 d,后期为18–30 d)。三个时期内共注释到真菌10门39纲98目226科461属。前期真菌构成复杂且持续变化,相互作用关系密切并受pH和总氮(total nitrogen,TN)影响;中期优势属发生变化且稀有属明显增多,互作关系减弱,并受TN调控;后期稀有属持续减少,群落结构简单,互作较少并受硝态氮(nitrate nitrogen,NN)、磷酸盐(phosphates,P)和总磷(total phosphorus,TP)影响。【结论】25℃密闭储存30 d的泡菜母水,其真菌群落在前、中、后3期的演替特点各不相同。25℃密闭储存的泡菜母水在一周内食用更安全,也能有效保障发酵泡菜的风味,冷链储存则可适当延长保存期。泡菜体系中蕴藏的丰富真菌资源值得挖掘。

关键词：扩增子测序泡菜母水母水储存稀有真菌群落演替

螺杆式空压机压缩空气含油量高的原因及处理措施

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现代制造技术与装备 2024年第4期60卷 68-70页

作者：李正强广东粤电新会发电有限公司江门529149

螺杆式空压机作为当前空压机行业的主流产品,广泛应用于需要压缩气体的行业。然而,由于润滑油质量不佳、高温环境的影响,螺杆式空压机经常出现压缩空气含油量过高的问题。基于此,分析了螺杆式空压机压缩空气含油量高的原因,提出相应的... 详细信息

螺杆式空压机作为当前空压机行业的主流产品,广泛应用于需要压缩气体的行业。然而,由于润滑油质量不佳、高温环境的影响,螺杆式空压机经常出现压缩空气含油量过高的问题。基于此,分析了螺杆式空压机压缩空气含油量高的原因,提出相应的处理措施。通过这些措施,可以有效降低螺杆式空压机压缩空气的含油量,提高设备的性能和可靠性。

关键词：螺杆式空压机干燥机过滤器

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芒柄花素促进牙囊干细胞成骨向分化

口腔医学研究 2024年第3期40卷 214-220页

作者：陶天翼李正强郑晓雪韩冰吉林大学口腔医院口腔颌面外科吉林省牙发育及颌骨重塑与再生重点实验室吉林长春130021 南方医科大学口腔医院口腔颌面外科广东广州510515 吉林省肿瘤医院耳鼻咽喉口腔颌面头颈外科吉林长春130012

目的:研究芒柄花素对牙囊干细胞(human dental follicle stem cells,hDFSCs)成骨分化的影响。方法:首先对hDFSCs进行分离、培养及鉴定,并使用含不同浓度芒柄花素(0、0.1、1、10μmol/L)培养基培养细胞。通过CCK-8实验、结晶紫染色和活/... 详细信息

目的:研究芒柄花素对牙囊干细胞(human dental follicle stem cells,hDFSCs)成骨分化的影响。方法:首先对hDFSCs进行分离、培养及鉴定,并使用含不同浓度芒柄花素(0、0.1、1、10μmol/L)培养基培养细胞。通过CCK-8实验、结晶紫染色和活/死细胞荧光染色评估细胞的活性状况;通过细胞骨架荧光染色观察细胞骨架状况;采用RT-qPCR检测细胞成骨相关基因的表达变化;利用碱性磷酸酶(alkaline phosphatase,ALP)染色及活性检测法评估细胞成骨分化过程中ALP活性的影响;通过茜素红染色法评估细胞成骨分化过程中钙化结节数量的影响。结果:hDFSCs具有干细胞特性;不同浓度的芒柄花素对hDFSCs活性无显著性影响;1μmol/L的芒柄花素可显著促进Runx2、OCN、Col-Iα1的mRNA表达;并能够提高的细胞内ALP活性和钙化结节的数量。结论:1μmol/L芒柄花素可促进hDFSCs的成骨分化。

关键词：芒柄花素牙囊干细胞成骨分化

基于低对比度红外图像时空信息的气体泄漏检测

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光学精密工程 2024年第8期32卷 1186-1198页

作者：左金辉徐文斌周世杰盛道斌徐向东李正强韩颖慧吴春江张磊中国科学院空天信息创新研究院国家环境保护卫星遥感重点实验室&遥感科学国家重点实验室北京100101 中国科学院大学北京100049 北京环境特性研究所光学辐射重点实验室北京100854 电子科技大学信息与软件工程学院四川成都610054 江苏安级联科技有限公司江苏南通226000 中国科学院大学资源与环境学院北京100049 四川易方智慧科技有限公司四川成都610000

气体泄漏事故造成的危害是多方面的,如环境污染、人员财产损失、火灾爆炸。红外热成像作为可实现大范围快速成像的定性探测技术被广泛使用,相比一般红外图像,气体红外图像的对比度更低,边缘更加模糊,不易识别。针对上述问题,本文提出一... 详细信息

气体泄漏事故造成的危害是多方面的,如环境污染、人员财产损失、火灾爆炸。红外热成像作为可实现大范围快速成像的定性探测技术被广泛使用,相比一般红外图像,气体红外图像的对比度更低,边缘更加模糊,不易识别。针对上述问题,本文提出一种基于混合高斯背景建模的低对比度气体红外图像泄漏检测方法。首先,在预处理阶段,提出时域自适应帧间滤波算法实现红外图像的降噪和细节保持;然后,基于空域信息和梯度信息约束,提出时空混合高斯背景模型实现泄漏气体目标的前景的初步提取;最后,为更好地去除前景检测中干扰的运动目标,利用改进的快速鲁棒的模糊C均值聚类方法实现气体区域的自适应分割。实验结果表明,在5 m的泄漏距离下,该检测算法可有效提高准确率,弥补气体区域空洞问题,降低其他运动物体的干扰,气体泄漏检测准确率在92.3%~96.3%,与其他算法相比具有显著的抗干扰和区域分割能力。

关键词：气体泄漏检测红外热成像时空高斯混合模型时域自适应帧间滤波运动检测快速和鲁棒的模糊C均值聚类

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