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Science China Chemistry 2010年第3期53卷 650-662页

作者： CHANG ChihChung CHOU C.K.Charles andreas wahner Research Center for Environmental Changes Academia SinicaTaipei 11529China Forschungszentrum Juelich ICG-Ⅱ:TroposphereJuelichGermany

An intensive field campaign including measurements from the environmental monitoring network and from two super sites took place in the Pearl River Delta region in summer *** routinely measured O3 and NOx concentrations,the spatial and temporal variation of O3 and of the total oxidant concentrations was *** to the spatial variability of NO2/NO,the two super sites were found to be representative of polluted urban and downwind suburban *** addition,both sites were located in high O3 ***-depth diagnostic of photochemical ozone production processes and their key controlling factors are achieved with an observation-based model(OBM) to gain regional *** analysis and sensitivity model runs show that aldehyde and HONO chemistry had significant impacts on local photochemical ozone production *** analysis of calculated Relative Incremental Reactivities shows that photochemical ozone production rates are mainly sensitive to anthropogenic hydrocarbons(HCs) in the polluted urban *** the suburban areas,sensitivity to nitrogen oxide(NO) concentrations *** anthropogenic HCs in both areas are alkenes and *** differences of ozone production efficiencies are identified between the urban and suburban regions,consistent with the OBM diagnosed results.

关键词： ozone Pearl River Delta photochemical ozone productions HONO relative incremental reactivity

Explicit diagnosis of the local ozone production rate and the ozone-NOx-VOC sensitivities

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Science Bulletin 2018年第16期63卷 1067-1076页

作者： Zhaofeng Tan Keding Lu Huabin Dong Min Hu Xin Li Yuhan Liu Sihua Lu Min Shao Rong Su Haichao Wang Yusheng Wu andreas wahner Yuanhang Zhang State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University. Beijing 100871 China Institute of Energy and Climate Research IEK-8: Troposphere Forschungszentrum julich GmbH Julich 52428 Germany Beijing Innovation Center for Engineering Sciences and Advanced Technology Peking University Beijing 100871 China

In the troposphere, ozone is a harmful gas compound to both human health and vegetation. Ozone is produced from the reaction of NO_x(@NO + NO_2) and VOCs(volatile organic compounds) with light. Due to the highly nonlinear relationships between ozone and its precursors, proper ozone mitigation relies on the knowledge of chemical mechanisms. In this study, an observation-based method is used to simulate ozone formation and elucidate its controlling factors for a rural site on the North China Plain. The instantaneous ozone production rate is calculated utilizing a box model using the dataset obtained from the Wangdu campaign. First, the model was operated in a time-dependent mode to calculate the ozone production rate at each time stamp. The calculated ozone formation rate showed a diurnal average maximum value of 17 ppbv/h(1-h diurnal averaged). The contribution of individual peroxy radicals to ozone production was analyzed. In addition, the functional dependence of calculated P(O_3) reveals that ozone production was in a NO_x-limited regime during the campaign. Furthermore, the missing peroxy radical source will further extend NO_x-limited conditions to earlier in the day, making NO_xlimitation dominate more of a day than the current chemical model predicts. Finally, a multiple scenarios mode,also known as EKMA(empirical kinetic modeling approach), was used to simulate the response of P(O_3) to the imaginary change in precursor concentrations. We found that ozone production was in the NO_x-limited region. However, the use of NO_2 measured by the molybdenum converter and/or the absence of a peroxy radical source in the current chemical model could over-emphasize the VOC-limited effect on ozone production.

关键词： Observational-based model Instantaneous ozone production rate (empirical kinetic modeling approach) EKMA

珠江三角洲夏季臭氧区域污染及其控制因素分析

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中国科学：化学 2010年第4期40卷 407-420页

作者：陆克定张远航苏杭邵敏曾立民钟流举向运荣张志忠周崇光 andreas wahner 环境模拟与污染控制国家重点联合实验室北京大学环境科学与工程学院北京100871 广东省环境监测中心广东510045 中央研究院环境变迁研究中心台北11529 Forschungszentrum Juelich Institute ICG-Ⅱ TroposphereJuelichGermany

2006年夏季,在珠江三角洲(简称珠三角)开展了一次大型野外综合空气质量观测实验.实验包括了珠三角现有的环境监测网络和两个额外设置的超级观测站.本文基于环境监测网络的观测结果对区域臭氧污染状况和污染过程进行了分析,对各站点所记... 详细信息

2006年夏季,在珠江三角洲(简称珠三角)开展了一次大型野外综合空气质量观测实验.实验包括了珠三角现有的环境监测网络和两个额外设置的超级观测站.本文基于环境监测网络的观测结果对区域臭氧污染状况和污染过程进行了分析,对各站点所记录的气团光化学属性进行了诊断.结果发现,两个超级站点分别对应着污染城市地区和下风向远郊区的光化学条件,它们较好地覆盖了区域尺度上主要的臭氧高值区.使用基于观测的模型对超级站上臭氧的光化学产生过程及臭氧控制区进行了分析.结果显示,第一,模式中的醛类化学和缺失的HONO化学对于臭氧光化学产生具有重要影响;第二,在城市地区,臭氧的光化学产生速率主要受人为源排放碳氢化合物控制;而在城市远郊区,臭氧的光化学产生速率主要受NO控制;第三,重要的人为源排放的碳氢化合物是烯烃和芳香烃.使用O′x和NOz的回归结果对臭氧产生效率进行了估算,发现城市和郊区的数值存在显著差异(分别为2.1和7.8),这从侧面支持了模型对于城市和郊区臭氧控制区属性的判断.

关键词：臭氧珠江三角洲臭氧光化学产生气态亚硝酸相对增量反应活性

Wintertime N2O5 uptake coefficients over the North China Plain

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Science Bulletin 2020年第9期65卷 765-774,M0004页

作者： Haichao Wang Xiaorui Chen Keding Lu Zhaofeng Tan Xuefei Ma Zhijun Wu Xin Li Yuhan Liu Dongjie Shang Yusheng Wu Limin Zeng Min Hu Sebastian Schmitt Astrid Kiendler-Scharr andreas wahner Yuanhang Zhang State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China Institute of Energy and Climate Research IEK-8:TroposphereForschungszentrum Jülich GmbHJülich 52428Germany Center for Excellence in Regional Atmospheric Environment Chinese Academy of SciencesXiamen 361021China Institute of Energy and Climate Research IEK-8:TroposphereForschungszentrum Julich GmbHJulich 52428Germany Now at TSI GmbH Aachen 52068Germany

The heterogeneous hydrolysis of dinitrogen pentoxide(N2O5)plays an important role in regulating *** N2O5 uptake coefficient,γ(N2O5),was determined using an iterative box model that was constrained to observational data obtained in suburban Beijing from February to March *** box model determined 2289 individualγ(N2O5)values that varied from<0.001 to 0.02 with an average value of 0.0046±0.0039(and a median value of 0.0032).We found the derived winterγ(N2O5)values in Beijing were relatively low as compared to values reported in previous field studies conducted during winter in Hong Kong(average value of 0.014)and the eastern ***(median value of 0.0143).In our study,field evidence of the suppression ofγ(N2O5)values due to pNO3-content,organics and the enhancement by aerosol liquid water content(ALWC)is in line with previous laboratory study *** ALWC,high pNO3-content,and particle morphology(inorganic core with an organic shell)accounted for the lowγ(N2O5)values in the North China Plain(NCP)during *** field-derivedγ(N2O5)values are well reproduced by a revised parameterization method,which includes the aerosol size distribution,ALWC,nitrate and organic coating,suggesting the feasibility of comprehensive parameterization in the NCP during wintertime.

关键词： N2O5 uptake coefficient Winter air pollution Nighttime chemistry Nitrate pollution

Pressure and temperature effects resulting from impact onto materials of different reactivity

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Defence Technology(防务技术) 2025年第2期44卷 221-230页

作者： andreas Heine Matthias Wickert Fraunhofer Institute for High-Speed Dynamics Ernst-Mach-InstitutEMIErnst-Zermelo-Str.4Freiburg im Breisgau79104Germany

The pressure and temperature increase resulting from the impact of different threats onto target materials is analyzed with a unified laboratory-scale *** allows deriving qualitative information on the occurring phenomenology as well as quantitative statements about the relative effects sizes as a function of target material and *** considered target materials are steel,aluminum,and *** threats,kinetic energy penetrator,explosively formed projectile,and shaped charge jet are *** the investigated combinations,the measured overpressures vary by a factor of up to 5 for a variation of the material,by a factor of up to 7 for a variation of the threat,and by a factor larger than 15for a simultaneous variation of *** obtained results as well as the experimental approach are relevant for the basic understanding of impact effects and risks due to material *** paper combines two main ***,to provide a summary of own prior work in a coherent journal article and,secondly,to review and discuss these earlier results with a new perspective.

关键词： Impact effects Pressure Temperature Risk assessment Material reactivity

2006年珠三角观测期间OH和HO2自由基的测量

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2006年珠三角观测期间OH和HO2自由基的测量

2014年夏季华北平原郊区站点(望都)ROx自由基的观测和模拟

第五届全国环境化学大会

作者：陆克定张远航 andreas Hofzumahaus Franz Rohrer andreas wahner 北京大学环境科学与工程学院

OH和HO自由基化学机制的研究对于理解全球气候的变化和区域空气污染的控制都具有重要意义。在现阶段,推进这项研究的关键环节之一就是开展包括OH和HO自由基直接测量的综合性野外观测。但是它们的化学寿命很短、浓度极低,其测量工作是迄... 详细信息

OH和HO自由基化学机制的研究对于理解全球气候的变化和区域空气污染的控制都具有重要意义。在现阶段,推进这项研究的关键环节之一就是开展包括OH和HO自由基直接测量的综合性野外观测。但是它们的化学寿命很短、浓度极低,其测量工作是迄今为止大气化学领域最富挑战性的工作之一。2006年,北京

关键词： HOx自由基激光诱导荧光(LIF) RACM

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2014年夏季华北平原郊区站点(望都)ROx自由基的观测和模拟

WNT/β-catenin-M2 macrophage interplay as a target for therapy against hepatocellular carcinoma:Role of Calculus bovis

中国化学会第30届学术年会-第二十六分会：环境化学

作者：陆克定张远航谭照峰曾立民刘禹含 Hendirk Fuchs andreas Hofzumahaus Frank Holland Xin Li andreas wahner 北京大学环境科学与工程学院 Institute of Energy and Climate Research IEK-8:TroposphereForschungszentrum Juelich GmbH

对大气氧化性普遍规律的认识,是理解臭氧和灰霾污染及全球辐射收支等重大环境问题的理论基础。ROx(=OH+HORO2)自由基化学作为对流层大气氧化能力的主要构成部分,其反应机理一直是国际大气化学研究的热点和前沿。基于自由基收支闭合实验... 详细信息

对大气氧化性普遍规律的认识,是理解臭氧和灰霾污染及全球辐射收支等重大环境问题的理论基础。ROx(=OH+HORO2)自由基化学作为对流层大气氧化能力的主要构成部分,其反应机理一直是国际大气化学研究的热点和前沿。基于自由基收支闭合实验思想,搭建了北京大学大气激光诱导荧光系统,在华北平原典型郊区站点开展了包含自由基直接准确测量的综合外场观测。观测结果显示华北平原存在高浓度自由基,OH、HO2、RO2的日间峰值浓度水平分别可达(5-15)×106cm-3,(3-14)×108 cm-3 and(3-15)×108 cm-3。使用基于观测的模型进行分析发现,目前最先进的大气化学机理在高VOCs和低NOx条件下仍然低估OH观测结果2倍左右。与之前珠三角和北京地区观测发现类似,向模型中引入"OH自由基非传统再生机制"可以实现对OH的准确模拟。此外,模型在清晨时段显著低估了RO2自由基观测结果,这说明清晨时段RO2自由基存在未知来源机制;同时这也意味着现有模型对局地臭氧光化学产生速率及其控制区的敏感性分析存在显著偏差。

关键词：激光诱导荧光 OH自由基 HO2自由基 RO2自由基 HONO

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World Journal of Gastroenterology 2025年第3期31卷 130-133页

作者： Tryfonas Mpektsis Anastasios Manolakis andreas Kapsoritakis Department of Gastroenterology University Hospital of LarisaLarisa 41100Greece

Liver cancer,and in particular hepatocellular carcinoma(HCC)is a disease of rising prevalence and *** date,definitive treatment options include either surgical excision or ablation of the affected *** increasing research on several pathways that could be involved in the progression of HCC,new elements within these pathways emerge as potential targets for novel *** WNT/β-catenin pathway favors the presence of M2 tumor-associated macrophages which in turn promote tumor growth and *** inhibition of this pathway is considered a good candidate for such targeted therapeutic ***,as Huang et al show in their recently published article,Calculus bovis which is used in traditional Chinese medicine can exert an inhibitory effect on theβ-catenin pathway and become a potential candidate for targeted pharmacotherapy against liver cancer.

关键词： Hepatocellular carcinoma Calculus bovis WNT/β-catenin pathway Tumorassociated macrophages

Microglia:a promising therapeutic target in spinal cord injury

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Neural Regeneration Research 2025年第2期20卷 454-463页

作者： Xiaowei Zha Guoli Zheng Thomas Skutella Karl Kiening andreas Unterberg Alexander Younsi Department of Neurosurgery Heidelberg University HospitalHeidelbergGermany Department of Neuroanatomy Institute for Anatomy and Cell BiologyHeidelberg UniversityHeidelbergGermany

Microglia are present throughout the central nervous system and are vital in neural repair,nutrition,phagocytosis,immunological regulation,and maintaining neuronal *** a healthy spinal cord,microglia are accountable for immune surveillance,however,when a spinal cord injury occurs,the microenvironment drastically changes,leading to glial scars and failed axonal *** this context,microglia vary their gene and protein expression during activation,and proliferation in reaction to the injury,influencing injury responses both favorably and unfavorably.A dynamic and multifaceted injury response is mediated by microglia,which interact directly with neurons,astrocytes,oligodendrocytes,and neural stem/progenitor *** a clear understanding of their essential nature and origin,the mechanisms of action and new functions of microglia in spinal cord injury require extensive *** review summarizes current studies on microglial genesis,physiological function,and pathological state,highlights their crucial roles in spinal cord injury,and proposes microglia as a therapeutic target.

关键词： astrocytes cytokines functional recovery immune regulation M1/M2 activation macrophages microglia neuroinflammation spinal cord injury therapy

Evaluating the Potential of Birch Bark Suberinic Acids for Solid Wood Impregnation

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Journal of Renewable Materials 2025年第1期13卷 147-161页

作者： Daniela Godina Guntis Sosins Aigars Paze Janis Rizikovs Raimonds Makars andreas Treu Latvian State Institute of Wood Chemistry Biorefinery LaboratoryRigaLV-1006Latvia Norwegian Institute of Bioeconomy Research Department Wood TechnologyHøgskoleveien 8Ås1433Norway

Instead of the traditional linear model of taking,making,and disposing,the circular bio-economy promotes a regenerative *** there is potential to create valuable products like betulin,lupeol,and suberinic acids(SA)from outer birch bark,many industries,such as plywood and pulp,often choose to incinerate substan-tial amounts of leftover birch bark to meet their energy *** highlights the importance of obtaining valu-able products from *** objective of this study was to examine various fractions of SA and assess their potential for wood *** fractions included SA potassium salts in ethanol(SAK-EtOH)and water(SAK-H2O),SA suspension in water(SAS-H2O)and dried SA,which was subsequently diluted in ethanol(DSA-EtOH).There is signiﬁcant potential for utilizing SA in wood treatment formulations as a sustainable alternative to harmful petroleum-derived *** approach not only addresses environmental concerns but also enhances the functionality of wood in construction applications,such as improving impregnation for moisture and fungal *** the solutions tested,the ethanol solution of SA,speciﬁcally DSA-EtOH,showed the highest weight percent gain(WPG)and the greatest leaching *** analysis showed that SA salts in ethanol(SAK-EtOH)and water(SAK-H2O)predominantly consist of low molecular fractions and each process(acidiﬁcation and drying)reduces the low molecular content in the *** suggests that SA polymerizes after drying,making it necessary to dissolve it in ethanol to meet the requirements for *** opti-mization,including adjustments in the concentration of the SA ethanol solution and the curing temperature,is essential to identify the optimal conditions for more in-depth impregnation studies.

关键词： Birch bark suberinic acids solid wood impregnation