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腈纶废水有机物的紫外高级氧化去除机制及反应动力学模拟

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环境科学学报 2024年第3期44卷 61-70页

作者：胡月张文珍李彦刚胡俊王辉李文涛强志民浙江工业大学环境学院杭州310014 中国科学院生态环境研究中心环境水质学国家重点实验室北京100085 北京城市排水集团有限责任公司北京100022 中国石油化工股份有限公司石油化工科学研究院北京100083

紫外高级氧化工艺(UV-AOP)可高效去除工业废水中的难降解有机物,然而,实际废水中成分复杂的有机物的降解去除机制和反应动力学研究还比较缺乏,限制了相关工艺的规模化应用.以某石化企业腈纶废水为对象,探究了UV/H_(2)O_(2)及VUV/UV/H_(2... 详细信息

紫外高级氧化工艺(UV-AOP)可高效去除工业废水中的难降解有机物,然而,实际废水中成分复杂的有机物的降解去除机制和反应动力学研究还比较缺乏,限制了相关工艺的规模化应用.以某石化企业腈纶废水为对象,探究了UV/H_(2)O_(2)及VUV/UV/H_(2)O_(2)工艺对废水有机物的降解去除机制并开展反应动力学分析.结果表明,腈纶废水有机物芳香性低,主要荧光组分为富里酸类和腐殖酸类物质.两种UV-AOP均可高效降解去除腈纶废水有机物,且相同处理条件下VUV/UV光源对有机物的去除效率略优于UV光源,原因在于VUV辐射的引入增加了反应体系中HO·的生成(增加了H_(2)O途径并强化了H_(2)O_(2)途径).在投加200 mg·L^(-1)H_(2)O_(2)、反应120 min后(UV剂量为23.4 J·cm^(-2)),UV/H_(2)O_(2)和VUV/UV/H_(2)O_(2)对酸性废水中COD的去除率分别为80.4%和91.3%.不同处理条件下腈纶废水有机物去除的单位能耗为0.154~0.193 kWh·g^(-1)COD,且处理后废水对费氏弧菌的发光抑制率都明显低于初始值,表明两种工艺在实际腈纶废水处理中具有较好的应用前景.基于废水有机物去除的拟一级动力学规律和自由基浓度稳态假设模型,计算得到了有机物(以DOC计)在UV辐射和HO·氧化作用下的反应速率常数,分别为1.83×10^(-6)cm^(2)·mJ^(-1)和1.24×10^(7)L·moL^(-1)·s^(-1).在此基础上,开发了可准确模拟腈纶废水有机物去除的计算流体动力学(CFD)模型,为工艺实际应用时的效能评估和参数优化提供了支持.

关键词： VUV/UV/H_(2)O_(2) 工业废水单位能耗急性毒性反应速率常数计算流体动力学(CFD)

An insight into the removal of fluoroquinolones in activated sludge process:Sorption and biodegradation characteristics

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Journal of Environmental Sciences 2017年第6期29卷 263-271页

作者： Lu Wang Zhimin Qiang yangang li Weiwei Ben Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

The detailed sorption steps and biodegradation characteristics of fluoroquinolones （FQs） including ciprofloxacin, enrofloxacin, lomefloxacin, norfloxacin, and ofioxacin were investigated through batch experiments. The results indicate that FQs at a total concentration of 500 μg/L caused little inhibition of sludge bioactivity. Sorption was the primary removal pathway of FQs in the activated sludge process, followed by biodegradation, while hydrolysis and volatilization were negligible. FQ sorption on activated sludge was a reversible process governed by surface reaction, Henry and Freundlich models could describe the FQ sorption isotherms well in the concentration range of 100-300 μg/L. Thermodynamic parameters revealed that FQ sorption on activated sludge is spontaneous, exothermic, and enthalpy-driven. Hydrophobicity-independent mechanisms determined the FQ sorption affinity with activated sludge. The zwitterion of FQs had the strongest sorption affinity, followed by cation and anion, and aerobic condition facilitated FQ sorption. PQs were slowly biodegradable, with long half-lives （〉100 hr）. FQ biodegradation was enhanced with increasing temperature and under aerobic condition, and thus was possibly achieved through co-metabolism during nitrification. This study provides an insight into the removal kinetics and mechanism of FQs in the activated sludge process, but also helps assess the environmental risks of FQs resulting from sludge disposal.

关键词： Fluoroquinolones Sorption Biodegradation Activated sludge

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氨法脱硫处理DCC硫酸铵浆液的研究与应用

石化技术 2024年第9期31卷 26-28页

作者：刘忠东李延岗朱瑞陕西延长中煤榆林能源化工股份有限公司陕西靖边718500

硫酸铵浆液中的催化剂等物质致使装置很难再环保指标达标的前提下正常出料,严重影响热动力站脱硫装置安全稳定运行。通过采用分塔、间断、少量处理方式方法,结合氨法脱硫塔内饱和结晶工艺与塔外蒸发结晶工艺的有效结合,确保脱硫装置在... 详细信息

硫酸铵浆液中的催化剂等物质致使装置很难再环保指标达标的前提下正常出料,严重影响热动力站脱硫装置安全稳定运行。通过采用分塔、间断、少量处理方式方法,结合氨法脱硫塔内饱和结晶工艺与塔外蒸发结晶工艺的有效结合,确保脱硫装置在处理渣油催化剂热裂解装置尾气脱硫(DCC)硫酸铵浆液过程中稳定运行。

关键词： DCC装置硫铵浆液催化剂

Analysis of the characteristics of offshore currents in the Changjiang(Yangtze River) estuarine waters based on buoy observations

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Acta Oceanologica Sinica 2017年第4期36卷 13-20页

作者： li Peng SHI Benwei WANG Yaping QIN Weihua li yangang CHEN Jian Forecast Center for East China Sea State Oceanic Administration Ministry of Education Key Laboratory for Coast and Island Development Nanjing University Marine Environment Investigation Center of East China Sea State Oceanic Administration

A buoy of 10 m in diameter was used to record the current speed and direction in a vertical profile in the offshore area of the Changjiang（Yangtze River） Estuary（with an average water depth of 46.0 m） for one *** results include：（1） the currents rotate clockwise and the current direction is consistent in a vertical profile without clear seasonal variations.（2） The horizontal current speeds are generally high,with a maximum of 128.5 cm/s occurring in summer and 105.5 cm/s appearing in winter commonly close to the *** average current speeds in the vertical profile fall in the same range（the differences are less than 8.0 cm/s）,with the maximum of47.0 cm/s occurring in summer and 40.8 cm/s in *** average current speed during spring tides is twice that during neap tides（26.5 cm/s）.（3） Significant differences of speeds are observed in the vertical *** maximum current speed occurs at either surface（spring and winter） or sub-surface（summer and autumn）,with the minimum current speed appearing at the *** maximum average current speed of all layers is 57.9cm/s,which occurs in the 18-m layer during summer.（4） The average speed of the residual currents ranges from7.5 cm/s to 11.3 cm/s,with the strongest occurring in spring and weakest in *** residual currents of all layers are eastward during spring and winter,whereas northeastward or northward during summer and autumn.（5） The currents in the offshore of Changjiang Estuary are impacted collectively by diluted Changjiang River discharge,the Taiwan Warm Current,monsoon and tides.

关键词： ocean currents buoy observation seasonal variations Changjiang(Yangtze River) Estuary

Coastal buoy observation of air-sea net heat flux in the East China Sea in summer 2020

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Journal of Oceanology and limnology 2022年第3期40卷 907-921页

作者： Yuting HAN yangang li Changsan XU Lei liU Yanling ZHAO Wenqing li Xiangzhou SONG Key Laboratory of Marine Hazards Forecasting Ministry of Natural Resources(MNR)Hohai UniversityNanjing 210024China National Marine Environmental Forecasting Center(NMEFC) Beijing 100081China East China Sea Bureau of MNR Shanghai 200081China Institute of Oceanographic Instrumentation Qilu University of TechnologyQingdao 266075China The PLA 31010 Units Beijing 100081China

The full fluxes and associated air-sea variables based on three months of operational buoy observations in the East China Sea(ECS)in summer 2020 were analyzed for the first *** surface net heat flux(Q_(net))was positive(139.7±77.7 W/m^(2))and was dominated by the combined eff ects of solar shortwave radiation(SW)and latent heat fluxes(LH).The mean heat flux components of 4 reanalysis datasets(NCEP2,MERRA-2,CFSR,and ERA5)and buoy data were compared to assess the mean ability of the modeling/reanalysis *** the four components of air-sea flux,SW was the best simulated,while LH was the worst *** longwave radiation(LW)and LH values from reanalysis were higher than those from buoy data,especially *** high LH resulted in low Q_(net).Furthermore,the 4 reanalysis datasets were compared with the buoy *** all flux products,the difference in radiation flux was the smallest,while that in the turbulent flux was the *** observed variables related to turbulent flux were analyzed to help determine the cause of the flux *** wind speeds were the main cause of this *** the variables provided by the reanalysis data and the same bulk formulas of the Coupled Ocean-Atmospheric Response Experiment(COARE 3.0),we found that the recalculated sensible heat flux(SH)and LH were closer to the observed heat fluxes than the direct model *** signifi cant diff erences between these methods could account for the discrepancies among diff erent *** all air-sea flux products,the air-sea flux in ERA5 was closer to the in-situ observations than the other *** comparison results of reanalysis data provide an important reference for more accurate studies of the summer heat flux in the ECS at the synoptic and climatic scales.

关键词： buoy observations East China Sea air-sea turbulent heat flux radiative flux reanalysis

Characterization of longshore currents in southern East China Sea during summer and autumn

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Acta Oceanologica Sinica 2020年第3期39卷 1-11页

作者： Peng li Benwei Shi yangang li Sijian Wang Xin Lv Yaping Wang Qing Tian Forecast Center for East China Sea State Oceanic AdministrationShanghai 200136China State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200062China School of Marine Sciences Nanjing University of Information Science and TechnologyNanjing 210044China

Current characteristics and vertical variations during summer and autumn in the southern East China Sea were investigated by measuring current profile, tide, wind, and wave data for 90 d from July 28 to October 25, 2015. Our results are:(1) The current was mainly a(clockwise) rotating flow, displaying reciprocating flow characteristics,and vertically the current directions were the same throughout the vertical profile.(2) The horizontal current speed was strongest during August(summer) with an average speed of 51.8 cm/s. The average current speeds during spring tides were highest in August and weakest in September, with speeds of 59.9 and 42.8 cm/s,respectively.(3) Considerable differences exist in average current speeds in different layers and seasons. The highest average current speeds were found in the middle–upper layers in August and in the middle–lower layers in September and October.(4) The residual current speed was highest in August, when the speed was 12.5–47.1 cm/s,whereas the vertical average current speed was 34.3 cm/s. The depth-averaged residual current speeds in September and October were only 50% of that in August, and the residual current direction gradually rotated in a counter-clockwise direction from the lower to surface layers.(5) Typhoon waves had a significant influence on the currents, and even affected the middle and lower water layers at depths of >70.0 m. Our results showed that the currents are controlled by the dynamic interplay of the Taiwan Warm Current, incursion of the Kuroshio Current onto the continental shelf, and monsoonal changes.

关键词： northeast Taiwan ocean current summer and autumn typhoon

Environmental heterogeneity regulates species-area relationships through the spatial distribution of species

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Forest Ecosystems 2022年第3期9卷 357-365页

作者： Chenqi He Leqi Fang Xinyu Xiong Fan Fan yangang li Luoshu He Xiaoli Shen Sheng li Chengjun Ji Jiangling Zhu Institute of Ecology College of Urban and Environmental SciencesKey Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing100871China School of life Sciences Peking UniversityBeijing100871China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing100093China

Species-area relationships(SARs),also known as species-area curves,are fundamental scaling tools for biodiversity *** design and taxonomic groups affect the widely cited forms of species-area ***,the influence of sampling design and related environmental heterogeneity on SAR curves is rarely ***,we investigated the SAR among different plant life forms(herbaceous plants,shrubs,and trees)in a 25.2-ha ForestGEO plot,the Wanglang Plot,in Sichuan,southwestern China,using a non-contiguous quadrat sampling method and power-law *** compared the estimated parameters(the intercept c and the slope z)of the power-law models among different plant life forms,tested whether the SAR curve forms varied with sampling starting location,and assessed the effect of environmental heterogeneity accumulating with sampling area on curve *** found a wider range of variations in the *** estimated c,z-values of power SAR were higher for the herbaceous plants than for the woody plants.A wider variation of SARs for the herbaceous plants than those for the woody *** selection of sampling starting location affected the SAR curve forms because of the roles of soil and topographic *** concluded that environmental heterogeneity regulates SAR curves sampled from different starting locations through spatial distribution of plant life ***,we recommend considering the design of sampling starting location when constructing SAR curves,especially in a heterogeneous habitat with unrandom distribution patterns of species.

关键词： Plants life forms Species-area curves Sampling design Spatial pattern Species diversity

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人民币汇率波动对中国股市的影响机制研究

广东金融学院学报 2011年第1期26卷 45-54页

作者：李延刚中海基金管理有限公司上海200120

通过协整检验和面板数据回归,检验汇率对股市影响的路径,并从宏观和微观(流动性和行业两个层面)研究二者时间的关系,结果表明人民币汇率与股市之间存在着相关关系,流动性与股市之间为正向相关关系,但是国际热钱与股市之间的相关关系并... 详细信息

通过协整检验和面板数据回归,检验汇率对股市影响的路径,并从宏观和微观(流动性和行业两个层面)研究二者时间的关系,结果表明人民币汇率与股市之间存在着相关关系,流动性与股市之间为正向相关关系,但是国际热钱与股市之间的相关关系并不显著;同时,汇率对不同行业股指的作用方向和影响程度并不相同,主要取决于行业的成本结构、出口价格弹性和外汇负债情况。但对于人民币汇率波动具体如何影响股市的问题,国内还有进一步深入研究的余地。

关键词：人民币汇率股市指数美元走势

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不同自我和谐水平青少年的认知加工偏向

心理学探新 2017年第5期37卷 429-433页

作者：马祎晨黎艳聂衍刚广州大学教育学院广州510006 广州大学心理与行为研究中心广州510006

为了探究不同自我和谐水平青少年的认知加工特点,44名被试先后进行自我相关词语的点-探测任务和词语的再认任务,结果发现:(1)高自我和谐水平的青少年对自我相关的积极词表现出注意优先,低自我和谐水平的青少年对自我相关的消极词表现出... 详细信息

为了探究不同自我和谐水平青少年的认知加工特点,44名被试先后进行自我相关词语的点-探测任务和词语的再认任务,结果发现:(1)高自我和谐水平的青少年对自我相关的积极词表现出注意优先,低自我和谐水平的青少年对自我相关的消极词表现出注意优先,但两者注意偏向无显著差异;(2)高自我和谐水平的青少年对自我相关的积极词的再认反应时显著短于低自我和谐水平青少年的,对积极词表现出了记忆偏向;低自我和谐水平的青少年对自我相关的消极词、中性词的再认反应时显著短于对积极词的反应时,对消极词、中性词表现出了记忆偏向。因此,不同自我和谐水平的青少年在认知加工的记忆阶段存在特质一致性。

关键词：自我和谐注意偏向记忆偏向