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温带森林土壤渗漏液DOM含量与组分及光谱特性

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环境科学与技术 2018年第12期41卷 169-178页

作者：苗敏吴浩浩韩琳傅平青徐星凯成都信息工程大学大气科学学院四川成都610225 中国科学院大气物理研究所大气边界层物理和大气化学国家重点实验室北京100029 中国科学院大学地球科学学院大气化学与环境科学系北京100049

文章利用连续流动分析和三维荧光光谱技术,研究了不同形态[(NH_4)_2SO_4、NH_4Cl和KNO_3]和剂量(22.5和45 kgN/(hm^2·a)模拟氮沉降、碳添加(葡萄糖,64 kgC/(hm^2·a)以及去除凋落物处理9 a后温带森林实验样地,在融化末期(5月)和植被生... 详细信息

文章利用连续流动分析和三维荧光光谱技术,研究了不同形态[(NH_4)_2SO_4、NH_4Cl和KNO_3]和剂量(22.5和45 kgN/(hm^2·a)模拟氮沉降、碳添加(葡萄糖,64 kgC/(hm^2·a)以及去除凋落物处理9 a后温带森林实验样地,在融化末期(5月)和植被生长旺期(7月)森林土壤渗漏液溶解性有机质(DOM)含量与组分及其光谱特性的变化规律。对实验所有处理森林土壤渗漏液三维荧光光谱进行平行因子分析,得到DOM的3个荧光组分:富里酸类DOM、腐殖酸类DOM和蛋白类DOM。在不考虑实验处理的影响,与融化末期相比,植被生长旺期森林土壤渗漏液溶解性有机碳(DOC)及其生物可降解(BDOC)含量均显著地增加,DOM中蛋白类组分贡献率较低、腐殖化程度较高、生物源贡献较少而陆源贡献较大。长期碳氮干扰对融化末期森林土壤渗漏液DOC含量及其生物可降解性均无显著影响。长期去除凋落物和碳添加处理降低了植被生长旺期森林土壤渗漏液DOC和BDOC含量。长期模拟氮沉降对森林土壤渗漏液DOM 3种组分的含量和贡献率的影响与外源氮的形态和剂量有关。该研究显示长期碳氮干扰条件下,在上述2种不同时期森林土壤渗漏液DOM的生物可降解性与荧光组分及相关参数所反映的DOM活性具有较高的一致性。实验结果为深入研究森林土壤渗漏液DOM含量和组分及其稳定性的影响因素提供参考。

关键词：森林土壤渗漏液氮沉降凋落物溶解性有机质三维荧光光谱-平行因子分析

Determination of Hg and MeHg complexation with dissolved organic matter by fluorescence quenching titration

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Acta Geochimica 2006年第S1期 264-265页

作者： pingqing fu1, Fengchang WU1, Feiyue WANG2 1 State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China 2 Department of Environment and Geography, and Department of Chemistry

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海洋大气气溶胶中生物标志物研究进展

地球与环境 2024年第2期52卷 230-243页

作者：胡伟王亚杰段沛敏靳蕊李晓东傅平青天津大学地球系统科学学院表层地球系统科学研究院

海洋气溶胶是海洋大气的重要组成部分,直接或间接影响地球系统的能量收支及气候变化。生物标志物如脂类、糖类、木质素类以及蛋白类化合物等,可用来识别海洋气溶胶的来源和提供重要的生物地球化学信息。然而,海洋气溶胶中单个有机物种... 详细信息

海洋气溶胶是海洋大气的重要组成部分,直接或间接影响地球系统的能量收支及气候变化。生物标志物如脂类、糖类、木质素类以及蛋白类化合物等,可用来识别海洋气溶胶的来源和提供重要的生物地球化学信息。然而,海洋气溶胶中单个有机物种的浓度很低,其检测和表征具有一定的挑战性。本文综述了海洋气溶胶中生物标志物的最新研究进展,包括检测方法、分子组成、来源和影响因素等。高分辨率色谱和质谱联用法广泛应用于海洋气溶胶中生物标志物测量,其他一些新兴的方法也被开发应用。海洋气溶胶中的脂类和糖类化合物的浓度呈现近岸高、远洋低的变化趋势,其浓度和组成随气象条件和排放源种类和强度变化呈现显著的季节特征,表明受到陆地长距离传输的影响。然而,更多研究强调了蛋白质和氨基酸的海洋生物来源,海洋排放的氨基酸在亚微米颗粒物上大量富集;蛋白质在长距离传输过程中由于光化学反应而降解。木质素也已被证明在远洋气溶胶中占比较高。此外,本文也指出了加强生物标志物在陆-海-气界面循环研究的必要性。

关键词：海洋气溶胶生物标志物分子组成长距离传输

Recent Progress in Atmospheric Chemistry Research in China: Establishing a Theoretical Framework for the “Air Pollution Complex”

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Advances in Atmospheric Sciences 2023年第8期40卷 1339-1361页

作者： Tong ZHU Mingjin TANG Meng GAO Xinhui BI Junji CAO Huizheng CHE Jianmin CHEN Aijun DING pingqing fu Jian GAO Yang GAO Maofa GE Xinlei GE Zhiwei HAN Hong HE Ru-Jin HUANG Xin HUANG Hong LIAO Cheng LIU Huan LIU Jianguo LIU Shaw Chen LIU Keding LU Qingxin MA Wei NIE Min SHAO Yu SONG Yele SUN Xiao TANG Tao WANG Tijian WANG Weigang WANG Xuemei WANG Zifa WANG Yan YIN Qiang ZHANG Weijun ZHANG Yanlin ZHANG Yunhong ZHANG Yu ZHAO Mei ZHENG Bin ZHU Jiang ZHU Peking University Beijing 100871China Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640China Hong Kong Baptist University Hong Kong SARChina Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China Chinese Academy of Meteorological Sciences Beijing 100081China fudan University Shanghai 200438China Nanjing University Nanjing 210023China Tianjin University Tianjin 300072China Chinese Research Academy of Environmental Sciences Beijing 100012China Ocean University of China Qingdao 266100China Institute of Chemistry Chinese Academy of SciencesBeijing 100190China Nanjing University of Information Science and Technology Nanjing 210044China Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Institute of Earth Environment Chinese Academy of SciencesXi’an 710061China University of Science and Technology of China Hefei 230026China Tsinghua University Beijing 100084China Anhui Institute of Optics and Fine Mechanics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Jinan University Guangzhou 510632China Hong Kong Polytechnic University Hong Kong SARChina Beijing Institute of Technology Beijing 100081China

Atmospheric chemistry research has been growing rapidly in China in the last 25 years since the concept of the“air pollution complex”was first proposed by Professor Xiaoyan TANG in *** papers published in 2021 on air pollution(only papers included in the Web of Science Core Collection database were considered),more than 24000 papers were authored or co-authored by scientists working in *** this paper,we review a limited number of representative and significant studies on atmospheric chemistry in China in the last few years,including studies on(1)sources and emission inventories,(2)atmospheric chemical processes,(3)interactions of air pollution with meteorology,weather and climate,(4)interactions between the biosphere and atmosphere,and(5)data *** intention was not to provide a complete review of all progress made in the last few years,but rather to serve as a starting point for learning more about atmospheric chemistry research in *** advances reviewed in this paper have enabled a theoretical framework for the air pollution complex to be established,provided robust scientific support to highly successful air pollution control policies in China,and created great opportunities in education,training,and career development for many graduate students and young *** paper further highlights that developing and low-income countries that are heavily affected by air pollution can benefit from these research advances,whilst at the same time acknowledging that many challenges and opportunities still remain in atmospheric chemistry research in China,to hopefully be addressed over the next few decades.

关键词： atmospheric chemistry air pollution complex theoretical framework recent progress

Loss Aware Feature Attention Mechanism for Class and Feature Imbalance Issue

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Computers, Materials & Continua 2025年第1期82卷 751-775页

作者： Yuewei Wu Ruiling fu Tongtong Xing fulian Yin College of Information and Communication Engineering Communication University of ChinaBeijing100024China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing100024China

In the Internet era,recommendation systems play a crucial role in helping users find relevant information from large *** imbalance is known to severely affect data quality,and therefore reduce the performance of recommendation *** to the imbalance,machine learning algorithms tend to classify inputs into the positive(majority)class every time to achieve high prediction *** can be categorized such as by features and classes,but most studies consider only class *** this paper,we propose a recommendation system that can integrate multiple networks to adapt to a large number of imbalanced features and can deal with highly skewed and imbalanced datasets through a loss *** propose a loss aware feature attention mechanism(LAFAM)to solve the issue of feature *** network incorporates an attention mechanism and uses multiple sub-networks to classify and learn *** better results,the network can learn the weights of sub-networks and assign higher weights to important *** propose suppression loss to address class imbalance,which favors negative loss by penalizing positive loss,and pays more attention to sample points near the decision *** on two large-scale datasets verify that the performance of the proposed system is greatly improved compared to baseline methods.

关键词： Imbalanced data deep learning e-commerce recommendation loss function big data analysis

Enhancing weather predictions:Initial condition sensitivity and error dynamics in data assimilation

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Science China Earth Sciences 2025年

作者： Weiwei fu Department of Atmospheric and Oceanic Sciences Fudan University Key Laboratory of Polar Atmosphere-ocean-ice System for Weather and Climate Ministry of Education Fudan University IRDR International Center of Excellence on Risk Interconnectivity and Governance on Weather Fudan University

Data Assimilation (DA) plays a crucial role in modern numerical forecasting (Kalnay, 2002). It has been demonstrated that incorporating real-time observational data into forecast models significantly enhances the accuracy of both shortterm weather forecasts (Bauer et al., 2015; Bannister, 2017)and long-term climate predictions (Karspeck et al., 2013;Mochizuki et al., 2016).

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重庆白市驿PM_(2.5)中糖类特征及来源

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环境科学学报 2024年第11期44卷 28-38页

作者：傅铃雁刘彬杨成思豪张舒涵邓小康苏靖柯徐成华傅平青刘頔任红成都信息工程大学资源环境学院成都610225 大气环境模拟与污染控制四川省高校重点实验室成都平原城市气象与环境四川省野外科学观测研究站成都610225 天津大学地球系统科学学院天津300072 中国科学院大气物理研究所北京100029

大气有机颗粒物是引起大气污染的重要成分之一,而四川盆地典型山地城市大气PM_(2.5)的有机分子示踪物组成及其特征研究相对国内其它热门城市较少.为探究四川盆地典型山地城市大气PM_(2.5)中糖类化合物的特征,利用气相色谱-质谱联用(GC-... 详细信息

大气有机颗粒物是引起大气污染的重要成分之一,而四川盆地典型山地城市大气PM_(2.5)的有机分子示踪物组成及其特征研究相对国内其它热门城市较少.为探究四川盆地典型山地城市大气PM_(2.5)中糖类化合物的特征,利用气相色谱-质谱联用(GC-MS)检测了重庆市白市驿不同季节PM_(2.5)昼夜样品中12种糖类化合物的浓度水平,包括脱水糖、初级糖和糖醇.结果表明:①重庆市白市驿大气PM_(2.5)中脱水糖占总糖的比例超过85%,其中,左旋葡聚糖占比最大.②总糖浓度为(264±208)ng·m^(-3),且白天浓度((226±198)ng·m^(-3))低于晚上浓度((307±212)ng·m^(-3)).③总糖浓度呈现季节差异,夏季((52.5±47.9)ng·m^(-3))<秋季((287±172)ng·m^(-3))<春季((294±206)ng·m^(-3))<冬季((420±176)ng·m^(-3)),主要受到气象条件、民用取暖、植被生长等多因素的影响.④分子标志物源解析结果表明,生物质燃烧(BB-OC)、植物碎屑(P-OC)和真菌孢子(F-OC)排放的有机碳(Organic Carbon,OC)浓度分别为(2166±1711)、(11.7±11.8)和(47.5±36.9)ng·m^(-3)(以C计,下同),其对的OC的贡献分别为16.9%、0.09%和0.53%.

关键词： PM_(2.5) 糖类生物质燃烧源解析重庆

Energy injection,transport,and dissipation in Earth's magnetosphere

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Science China Earth Sciences 2025年

作者： Huishan fu Jinbin CAO School of Space and Earth Sciences Beihang University Key Laboratory of Space Environment Monitoring and Information Processing Ministry of Industry and Information Technology

The Earth's magnetosphere is a region occupied by many artificial satellites, and also is a region that spacecraft must cruise during the deep-space exploration. In this sense, the Earth's magnetosphere is closely related to human activity and is a candidate for us to expand our living space. Generally, the Earth's magnetosphere can preclude most energetic particles from the Sun and the interstellar space, effectively protecting human beings on the Earth from being attacked and thus making the Earth to be a habitable planet. However, in some conditions, the Earth's magnetosphere becomes dynamic and energetic, and consequently may damage the artificial satellites, threaten the astronauts' health, and disrupt the ground infrastructure, which leads to a decline in the national economy. Therefore, investigating how energy is injected into the magnetosphere, how it is transported in the magnetosphere, and how it is ultimately dissipated in the magnetosphere are the key issues in space physics. Targeting these key issues, in this paper, we review the recent progress on them. Particularly, we introduce the relevant scientific questions,models, methods, and spacecraft missions, for better building a physical link among the energy injection, transport, and dissipation in the magnetosphere, present an energy chain of the magnetosphere, reveal the relationship between such energy chain and the space weather events, and discuss the forecasting and warning methods for energetic-particle events in the magnetosphere. The magnetospheric energy chain discussed in this paper will help us reveal the mechanisms of space weather events, establish the models of space environment, and forecast the disastrous space weather events.

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PS-CoT-Adapter: adapting plan-and-solve chain-of-thought for ScienceQA

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Science China(Information Sciences) 2025年第1期68卷 392-393页

作者： Qun LI Haixin SUN fu XIAO Yiming WANG Xinping GAO Bir BHANU School of Computer Science Nanjing University of Posts and Telecommunications Purple Mountain Laboratories Department of Electrical and Computer Engineering University of California at Riverside

Large language models (LLMs) have recently shown remarkable performance in a variety of natural language processing (NLP) *** further explore LLMs'reasoning abilities in solving complex problems,recent research [1-3]has investigated chain-of-thought (CoT) reasoning in complex multimodal scenarios,such as science question answering (ScienceQA) tasks [4],by fine-tuning multimodal models through human-annotated CoT ***,collected CoT rationales often miss the necessary rea-soning steps and specific expertise.

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