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Study on the Radiation Synthesis Mechanism and the Electrochemical Property of Polyaniline

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CHINESE JOURNAL OF POLYMER SCIENCE 2025年第2期43卷 328-340页

作者： Yan, Shuo Guo, Zi-Fang Ge, Zhi-Qing Zhang, Bao-Ying Zhang, Ya-Ru Li, Yi-Shao Wang, Mo-Zhen Ge, xue-wu Univ Sci & Technol China Dept Polymer Sci & Engn State Key Lab Precis & Intelligent Chem Hefei 230026 Peoples R China Univ Sci & Technol China Sch Nucl Sci & Technol Hefei 230026 Peoples R China

As a highly promising conductive polymer material, the synthesis method, structure regulation, and performance improvement of polyaniline (PANI) are hot research topics. In this work, the radiation-induced polymerization of aniline in HNO3 solution was successfully achieved at room temperature without the use of chemical oxidants. Through the analysis of the radiation chemical reactions of inorganic acids and nitrate salt solutions, the characterization of the intermediate free radicals in the irradiated systems, and the influence of the pH of the solutions on the polymerization activity and product morphologies, the radiation-induced polymerization mechanism of aniline is discussed in detail and proposed. Only at a condition of [HNO3]>[aniline], i.e., pHNO3 generated by radiolysis reactions, and undergoes repeated three steps of monomer free radical recombination, deprotonation, and oxidation reaction of NO3, thus forming a PANI macromolecule. In addition to the polymerization reaction, the aniline units are protonated and oxidized because of the strongly acidity and oxidation of the reaction system under gamma-ray irradiation, which means that the molecular chain structure of the radiation-synthesized PANI can be regulated by pH, nitrate concentration, and irradiation conditions. Radiation-synthesized PANI has a moderate protonation and oxidation state, which can be used for the preparation of PANI supercapacitors with better electrochemical properties than those prepared by chemical oxidation under the same conditions. This work presents a new radiation-synthesis method and polymerization mechanism of PANI, which not only expands the application of radiation technique in the field of polymer synthesis, but also provides a new idea for the structural regulation and electrochemical p

关键词： Aniline Radiation-induced polymerization Polyaniline Electrochemical property

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考虑交通拥堵的众包取送货低碳路径优化

交通运输系统工程与信息 2025年第1期25卷 188-201页

作者：吴雪胡大伟王茵长安大学运输工程学院西安710064

依据不同交通拥堵状况下的车辆行驶时间计算方法,考虑众包配送车辆路径-速度的联合优化,本文提出时间依赖型众包取送货问题(the Time-Dependent Crowdshipping Pickup and Delivery Problem,TDCPDP),构建混合整数规划模型。设计一类嵌... 详细信息

依据不同交通拥堵状况下的车辆行驶时间计算方法,考虑众包配送车辆路径-速度的联合优化,本文提出时间依赖型众包取送货问题(the Time-Dependent Crowdshipping Pickup and Delivery Problem,TDCPDP),构建混合整数规划模型。设计一类嵌套自由流速度优化机制的改进自适应大邻域搜索算法(the Improved Adaptive Large Neighborhood Search,IALNS)求解模型,以集成路径和速度决策。该算法采用一类回溯寻优的新策略避免陷入局部最优,提出几种移除-修复算子充分探索解空间,引入算子选择的自适应机制提升搜索效率。算法有效性验证部分,对比本文算法与基于扰动的算法、蚁群算法、变邻域搜索算法和自适应大邻域搜索算法,表明IALNS算法的优越性。灵敏度分析表明,相对于车辆以恒定高速或恒定低速行驶,自由流速度优化机制在维持碳排放较低的情况下使配送成本分别降低了3.97%和20.91%;配送成本和碳排放对车辆绕行和众包车补偿价值较为敏感,当众包车辆旅行时间限制和众包车单位时间补偿成本保持在合理范围内时,众包配送的碳排放和成本均维持在较低水平。

关键词：系统工程路径优化改进自适应大邻域搜索算法众包配送拥堵碳排放速度优化

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基于权衡协同效应的安徽省生态功能区识别及情景模拟

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中国环境科学 2025年第1期45卷 450-464页

作者：黄木易汤玉茹郭芹吴雪安徽建筑大学环境与能源工程学院安徽合肥230601 安徽省生态文明研究院安徽合肥230601 安徽省环境污染控制与资源化重点实验室安徽合肥230601 安徽建筑大学建筑与规划学院安徽合肥230601

基于生态系统服务及其权衡/协同效应的时空分布特征进行生态功能区划,能有效满足特定区域在协调多种生态系统服务方面存在的现实需求,根据不同生态系统服务的特定生态属性,制订相应的管理策略,有助于研究区的可持续发展.基于生态系统服... 详细信息

基于生态系统服务及其权衡/协同效应的时空分布特征进行生态功能区划,能有效满足特定区域在协调多种生态系统服务方面存在的现实需求,根据不同生态系统服务的特定生态属性,制订相应的管理策略,有助于研究区的可持续发展.基于生态系统服务权衡/协同效应识别生态功能区可为生态功能修复与治理提供精准和差异化调控依据.以安徽省为例,应用InVEST模型评估和分析2000~2020年间安徽省典型生态系统服务时空演变及权衡/协同效应,基于SOM(自组织映射)模型提取的生态系统服务簇,划分生态功能区,最后运用PLUS模型模拟2050年综合生态系统服务演变趋势并提出调控思路.结果表明:①安徽省2000~2020年期间,产水服务、土壤保持不断增加,而固碳服务、生境质量及粮食供给则呈降低趋势.安徽省综合生态系统服务指数空间格局为“南高北低”.研究区能提供两类生态系统服务的区域约占50%,能提供全部生态服务的区域仅约占11%,不能提供生态系统服务的区域分别由2000年的0.07%上升到2020年的4.85%.②产水服务、固碳服务、生境质量和土壤保持这4种生态系统服务间存在密切的协同效应,而产水服务和粮食生产存在明显的权衡效应.③据此为研究区提取了4种生态系统服务簇,分别为粮食供给簇、生态保育簇、人居环境簇和森林防护簇.最终将安徽省域划分为农业生态区、生态涵养区、城镇发展区和森林生态防护区,并提出差异化调控对策.④多情景模拟分析显示,生态保护情景下的生境质量和固碳服务最优,粮食生产在耕地保护情景下最高,在生态保护情景下,综合生态系统服务呈现出显著提升的态势.研究结果可为安徽省可持续发展和生态环境优化提供科学依据.

关键词：生态系统服务权衡协同效应生态功能分区多情景模拟安徽省

第一性原理对M@B_(12)N_(12)(M=Sc-Zn)团簇结构和性质的研究

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原子与分子物理学报 2025年第4期42卷 93-99页

作者：张颂程露吴学科凯里学院理学院凯里556011

利用基于密度泛函理论的第一性原理对M@B_(12)N_(12)(M=Sc-Zn)团簇的几何、电子结构,电偶极性和红外吸收光谱进行详细的研究.结果显示:当B_(12)N_(12)团簇内嵌过渡金属原子后,虽然结构稳定性稍稍降低,但其化学活性得到提高,摩尔体积明... 详细信息

利用基于密度泛函理论的第一性原理对M@B_(12)N_(12)(M=Sc-Zn)团簇的几何、电子结构,电偶极性和红外吸收光谱进行详细的研究.结果显示:当B_(12)N_(12)团簇内嵌过渡金属原子后,虽然结构稳定性稍稍降低,但其化学活性得到提高,摩尔体积明显增大.过渡金属原子与B_(12)N_(12)结合的过程中,除Cu和B原子外,剩余金属与N原子的Mulliken电荷出现负值.另外,金属原子的加入,不仅增加电偶极矩和极化率的值,还促使其红外吸收光谱发生红移.

关键词：团簇结构性质第一性原理

Evaluation of nutrient limitation in aquatic ecosystems with nitrogen fixing bacteria

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Journal of Environmental Sciences 2006年第3期18卷 537-542页

作者： wu Gen-fu wu xue-chang XUAN Xiao-dong ZHOU xue-ping College of Life Sciences Zhejiang University Hangzhou 310012 China Science and Technology Committee of Zhejiang Hangzhou 310006 China Institute of Biotechnology Zhejiang University Hangzhou 310029 China

There has always been a great need for simple and accurate bioassays for evaluating nutrient limitation in aquatic ecosystems. Whereas organic carbon is usually considered to be the limiting nutrient for microbial growth in many aquatic ecosystems, there are, however, many water sources that are limited by phosphorus or nitrogen. A method named ＂nitrogen fixing bacterial growth potential＂（NFBGP） test, which is based on pre-culturing of autochthonous （target） microorganisms was described. The method was applied to evaluate phosphorus or nitrogen nutrient limitation in lake and sewage water samples using an isolate of the nitrogen fixing bacterium, Azorhizobium sp. WS6. The results corresponded well to those from the traditional algal growth potential （AGP） test and the bacterial regrowth potential （BRP） test, suggesting that the NFBGP test is a useful supplementary method for evaluating the limiting nutrient, especially phosphorus, in an aquatic environment.

关键词： environment monitoring nitrogen fixing bacterium limiting nutrient phosphorus growth potential

Study of pollutant transport in depth-averaged flows using random walk method

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Journal of Hydrodynamics 2019年第2期31卷 303-316页

作者： xue-fei wu Dongfang Liang School of Environment and Resource Southwest University of Science and TechnologyMianyang 621010China Department of Engineering University of CambridgeCambridgeUK

The random walk particle tracking(RWPT)method is compared with the Eulerian methods in investigating pollutant transport in depth-averaged *** a typical representative of the Eulerian model with high performance,the MacCormack scheme with Total Variation Diminishing modification(TVD-Mac)is selected for *** concentration is simulated in four case ***,both numerical models have been tested in two idealized cases and compared against analytical *** dissipation is observed for TVD-Mac model where the concentration changes abruptly,especially under the circumstances of low resolution and misalignment between the flow direction and grid *** the contrary,simulations by the random walk model achieve higher accuracy in both cases and are free of fictitious oscillations in the vicinity of sharp concentration ***,the solute oscillation along a one-dimensional hypothetical tidal estuary is simulated,with the RWPT accurately con serving mass and suffering less rm merical diffusion compared with the Eulerian ***,the process of pollutant transport in a Yangzte River reach is predicted by the *** longitudinal dispersion coefficient DL is calculated *** is compared favorably with the theoretical/empirical formulae,indicating the validity of the RWPT in solving complex natural problems.

关键词： Pollutant transport depth-averaged flows random walk particle tracking TVD-MacCormack

Generalized Thermal Instability Criterion of Black Hole Accretion Disks

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Chinese Physics Letters 1998年第7期15卷 542-544页

作者： wu xue-bing Beijing Astronomical Observatory Chinese Academy of SciencesBeijing 100012 Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100080

The conventional thermal instability criterion cannot be applied to the advection-dominated accretion disks around black holes where the radiative cooling is insufficient to balance the viscous *** surface density change associated with the temperature perturbations,which was usually neglected in deriving the conventional criterion,was recently shown to be much significant in the advection-dominated *** both advection and surface density change,a generalized thermal instability criterion is *** applying it to the optically thin and optically thick advection-dominated disks,it is found that the former one is thermally stable and the latter one is thermally unstable against short wavelength perturbations,which agrees well to those found recently by both analytic and quantitative stability analyses.

关键词： criterion perturbations Criterion

First in situ UV profile across the UTLS accompanied by ozone measurement over the Tibetan Plateau

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Journal of Environmental Sciences 2020年第12期32卷 71-76页

作者： Jinqiang Zhang Xiangao Xia xue wu Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing210044China University of Chinese Academy of Sciences Beijing 100049China

Ultraviolet radiation(UV) and ozone can greatly affect human health and the Earth's ecological environment. By deploying a UV radiometer aboard a stratospheric balloon released at Qaidam(QDM) during the Asian summer monsoon(ASM) period in 2019, we provided in situ measurement of the UV profiles from the surface to the upper troposphere and lower stratosphere over the Tibetan Plateau(TP), China, for the first time. Based on two in situ UV profiles accompanied by four ozonesonde measurements, this study exhibited detailed variations of downwelling UV and vertical ozone distributions over the TP during the ASM period. The UV differences between the surface and stratospheric balloon flight altitudes were 16.7, 15.8, 12.6 and 18.0 Wm^-2 during the four ozonesonde launches. Due to the diurnal variations in photochemical production and the stratosphere-troposphere exchange, the integrated ozone columns below 30 km ranged from 184.4 to 221.6 DU from four ozonesonde measurements. A positive correlation between UV attenuation and ozone column was exhibited under low cloud cover and clear sky conditions. The results of this study are expected to improve our understanding of UV and ozone properties, as well as their potential effects on terrestrial ecosystems and living environments over this significant plateau.

关键词： Ultraviolet radiation Ozone In situ measurements Asian summer monsoon Tibetan Plateau

Ten-Year Climatological Features and Air Origin of Midlatitude Double Tropopauses

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Advances in Atmospheric Sciences 2015年第12期32卷 1592-1602页

作者： wu xue Lü Daren Key Laboratory for Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences

The 10-year climatological features related to midlatitude double tropopause events （DTs） are examined using ERA- Interim data from 2003 to 2012. The analysis is based on tropopauses defined by lapse rate. Results show that DTs are permanent or semi-permanent in the midlatitudes, and high DT frequency bands move poleward in winter and equatorward in summer, which is consistent with the seasonal movement of the subtropical jet. Based on our statistics, the second tropopause is found at about 100 hPa in the subtropics and at slightly lower altitudes in sub-polar regions. The thickness between the first and second tropopause is smaller in the subtropics and increases with latitude. Next, the origin of air sandwiched between the first and second tropopause of DTs is studied with a revised version of the UK Universities Global Atmospheric Modelling Programme Offline Trajectory Code （Version 3） diabatic trajectory model. The results show that, in the lower or middle troposphere, air is transported into the DTs from lower latitudes, mainly in the tropics. The dominant source regions are mainly areas of deep convection and steep orography, e.g., the western Pacific and Himalayan Mountains, and they show strong seasonality following the seasonal shift of these strong upwelling regions.

关键词： double tropopause trajectory model stratosphere-troposphere exchange