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Effects of hydrodynamics processes on phosphorus fluxes from sediment in large,shallow Taihu Lake

Journal of Environmental Sciences 2007年第9期19卷 1055-1060页

作者： you ben-sheng ZHONG Ji-cheng FAN Cheng-xin WANG Tong-cheng ZHANG Lu DING Shi-ming State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China. Graduate University of Chinese Academy of Sciences Beijing 100049 China Jiangsu Provincial Academy of Environmental Science Nanjing 210036 China Nanjing Institute of Environmental Sciences State Environmental Protection Administration Nanjing 210042 China

The turnover of phosphorus （P） in lake sediments, a major cause of eutrophication and subsequent deterioration of water quality, is in need of deep understanding. In this study, effects of resuspension on P release were studied in cylindrical microcosms with Yshape apparatus. The results indicated that there was a positive correlation between flux of suspended substance across sediment-water interface （Fss） and the wind speed, and an increasing Fss during each wind process followed by a steady state. The maximal Fss under fight, moderate, and strong wind conditions were 299.9±41.1,573.4±61.7, and 2093.8±215.7 g/m^2, respectively. However, flux of P across sediment-water interface （Fp） did not follow a similar pattern as Fss responding to wind intensity, which increased and reached the maximum in initial 120 rain for fight wind, then decreased gradually, with maximal flux of 9.4±1.9 mg/m^2. A rapid increase of Fp at the first 30 rain was observed under moderate wind, with maximal flux of 11.2±0.6 mg/m^2. Surprisingly, strong wind caused less Fp than under light and moderate wind conditions with maximal flux of 3.5±0.9 mg/m^2. Fss in water column declined obviously during the sedimentation process after winds, but Fp varied with wind regime. No obvious difference was detected on Fp after 8 h sedimentation process, compared with the initial value, which means little redundant P left in the water column after winds.

关键词： hydrodynamic process resuspension sedimentation phosphorus flux Taihu Lake

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Influence of Sediment Dredging on Chemical Forms and Release of Phosphorus

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Pedosphere 2008年第1期18卷 34-44页

作者： ZHONG Ji-Cheng you ben-sheng FAN Cheng-Xin LI Bao ZHANG Lu DING Shi-Ming State Key Laboratory of Lake Science and Environment Nanjin9 Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 (China) Graduate School of the Chinese Academy of Sciences Beijin9 100089 (China)

A laboratory experiment was carried out through a six-month incubation of undredged （control） and dredged cores to study the effect of sediment dredging on phosphorus （P） release from the sediment in the Taihu Lake. During the experiment, dredging the upper 30 cm layer could efficiently reduce the interstitial PO4^3-P concentration and different P forms in the sediment. The P fluxes of the undredged and dredged cores ranged from -5.1 to 3047.6 and -60.7 to 14.4μg·m^-2·d^-1, respectively. The fluxes of the dredged cores were generally lower than those of the control. Differences in the fluxes between the dredged and undredged cores were statistically significant （P 〈 0.05） from March to June 2006. The sediment P in the dredged cores had a lower release potential than that in the control. Dredging can be considered as a useful measure for rehabilitating the aquatic ecosystem after the external P loading in the Talhu Lake catchment was efficiently reduced.

关键词： phosphorus forms phosphorous release sediment dredging Taihu Lake

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Molecular mechanism for the unusual enhancement of the second-step chemiluminescence production from the carcinogenic tetrabromohydroquinone and H2O_(2)

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Journal of Environmental Sciences 2024年第7期141卷 330-342页

作者： Zi-Han Wang Chun-Hua Huang Zhi-sheng Liu Li Mao ben-Zhan Zhu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China College of Environment and Resources University of Chinese Academy of SciencesBeijing 100049China

We have found recently that two-step intrinsic hydroxyl radical(·OH)-dependent chemiluminescence(CL)could be produced by carcinogenic tetrahaloquinone and H_(2)O_(2).However,the first-step CL was too fast to clearly detect the stepwise generation of·OH and CL,and to distinguish the exact dividing point between the first-step and second-step *** we found that,extremely clear two-step intrinsic CL could be produced by the relative slow reaction of tetrabromohydroquinone(TBHQ)with H_(2)O_(2),which was directly dependent on the two-step·OH ***,the second-step,but not the first-step CL production of TBHQ/H_(2)O_(2)(CRET donor)was markedly enhanced by fluorescein(a typical xanthene dye,CRET acceptor)through a unique chemiluminescence resonance energy transfer(CRET)*** novel CRET system of TBHQ/H_(2)O_(2)/fluorescein was successfully applied for the sensitive detection of TBHQ with the detection limit as low as 2.5μmol/*** findings will help to develop more sensitive and highly efficient CL or CRET systems and specific CL sensor to detect the carcinogenic haloquinones,which may have broad environmental applications.

关键词： Two-step chemiluminescence Bromohydroquinone Hydrogen peroxide Hydroxyl radical CRET

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Full waveform inversion based on hybrid gradient

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Petroleum Science 2024年第3期21卷 1660-1670页

作者： Chuang Xie Zhi-Liang Qin Jian-Hua Wang Peng Song Heng-Guang Shen sheng-Qi Yu ben-Jun Ma Xue-Qin Liu Qingdao Innovation and Development Base Harbin Engineering UniversityQingdao266000ShandongChina Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao266000ShandongChina CNOOC Research Institute Co. Ltd.Beijing100028China College of Marine Geoscience Ocean University of ChinaQingdao266100ShandongChina Weihai Sunfull Geophysical Exploration Equipment Co. Ltd.Weihai264209ShandongChina

The low-wavenumber components in the gradient of full waveform inversion(FWI)play a vital role in the stability of the ***,when FWI is implemented in some high frequencies and current models are not far away from the real velocity model,an excessive number of low-wavenumber components in the gradient will also reduce the convergence rate and inversion *** solve this problem,this paper firstly derives a formula of scattering angle weighted gradient in FWI,then proposes a hybrid *** hybrid gradient combines the conventional gradient of FWI with the scattering angle weighted gradient in each inversion frequency band based on an empirical formula derived *** weighted hybrid mode,we can retain some low-wavenumber components in the initial lowfrequency inversion to ensure the stability of the inversion,and use more high-wavenumber components in the high-frequency inversion to improve the convergence *** results of synthetic data experiment demonstrate that compared to the conventional FWI,the FWI based on the proposed hybrid gradient can effectively reduce the low-wavenumber components in the gradient under the premise of ensuring inversion *** also greatly enhances the convergence rate and inversion accuracy,especially in the deep part of the *** the field marine seismic data experiment also illustrates that the FWI based on hybrid gradient(HGFWI)has good stability and adaptability.

关键词： Full waveform inversion Hybrid gradient Scattering angle weighted Low-wavenumber component

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地下水流量预测的多元线性回归分析模型研究

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水文 2006年第6期26卷 36-37页

作者：向速林刘占孟尤本胜华东交通大学土建学院江西南昌330013 中科院南京地理与湖泊研究所江苏南京210008

地下水系统是一个复杂的随机系统,本文根据地下水流量与其影响因素之间存在的相关关系,建立了一个基于线性回归分析法的地下水流量预测模型,并将其用于遵义市海龙坝的地下水流量预测。结果表明预测精度较高,建立的模型较符合本研究区的... 详细信息

地下水系统是一个复杂的随机系统,本文根据地下水流量与其影响因素之间存在的相关关系,建立了一个基于线性回归分析法的地下水流量预测模型,并将其用于遵义市海龙坝的地下水流量预测。结果表明预测精度较高,建立的模型较符合本研究区的实际情况。

关键词：地下水流量预测降雨量多元线性回归分析模型

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太湖流域漕桥河污染物来源特征

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环境科学研究 2009年第10期22卷 1150-1155页

作者：张利民刘伟京尤本胜边博江苏省环境科学研究院江苏南京210036

基于对太湖流域漕桥河小流域主要污染物来源构成和污染特征的分析,对污染物入河量进行了计算和修正.结果表明:漕桥河的CODCr入河总量为1 639.9 t/a,主要来源于工业污染和城镇生活污染;氨氮入河总量为174.6 t/a,主要来源于农业面源和工... 详细信息

基于对太湖流域漕桥河小流域主要污染物来源构成和污染特征的分析,对污染物入河量进行了计算和修正.结果表明:漕桥河的CODCr入河总量为1 639.9 t/a,主要来源于工业污染和城镇生活污染;氨氮入河总量为174.6 t/a,主要来源于农业面源和工业污染;总氮和总磷入河总量分别为491.0和34.7 t/a,主要来源于农业面源和城镇生活污染.同时,针对河网地区水系错综复杂的特性,将客水污染纳入污染源范畴,核定客水量,为有效改善河流水环境质量提供了依据.

关键词：污染物来源构成污染特征入河量客水污染

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太湖草型湖区沉积物再悬浮对水体营养盐的影响

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环境科学 2008年第1期29卷 26-31页

作者：尤本胜王同成范成新钟继承尹洪斌李宝中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室国家环境保护总局南京环境科学研究所南京210042

再悬浮过程中沉积物对水体营养盐的内源贡献是湖泊,特别是浅水湖泊富营养化研究中的重要问题.采用原位沉积物柱样和原状上覆水的Y型扰动装置,被用来研究常规风情下太湖草型湖区沉积物的再悬浮和沉降过程对水体营养盐负荷的影响.结果表明... 详细信息

再悬浮过程中沉积物对水体营养盐的内源贡献是湖泊,特别是浅水湖泊富营养化研究中的重要问题.采用原位沉积物柱样和原状上覆水的Y型扰动装置,被用来研究常规风情下太湖草型湖区沉积物的再悬浮和沉降过程对水体营养盐负荷的影响.结果表明,小风和中风的再悬浮过程导致水体氨氮和磷酸根磷含量显著下降,单位面积水柱含量最大变化量分别为-0.140 g.m-2和-1.59 mg.m-2;大风条件下,水体氨氮含量下降幅度很小,磷酸盐则出现明显增加趋势,最大增量为0.81mg.m-2.再悬浮过程之后的沉降过程中,中、小风条件的水体氨氮含量变小,大风条件的含量没有明显变化.磷酸根磷含量在中、小风条件下与风浪前差别较小,大风条件的含量则明显增大,最大增量为1.36 mg.m-2.因此,沉积物的再悬浮过程和沉降过程对上覆水体的营养盐动态负荷都产生重要影响.与太湖无植被湖区的研究结果对比说明,水生植物的存在对风浪作用下沉积物与上覆水的物质交换有一定的抑制作用.

关键词： Y型装置沉积物再悬浮沉降营养盐水生植物太湖

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风浪作用下太湖草型湖区水体N、P动态负荷模拟

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中国环境科学 2008年第1期28卷 33-38页

作者：尤本胜王同成范成新钟继承尹洪斌李宝龚海龙中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室国家环境保护总局南京环境科学研究所江苏南京210042 无锡市水利设计研究院有限公司江苏无锡214023

采用Y型旋浆式沉积物再悬浮装置研究了不同风速下太湖水生植被区沉积物的再悬浮和沉降过程.结果表明,中、小风过程中,随悬浮物浓度的增大,水体氨氮和磷酸盐浓度均显著增加,最大通量分别为0.063g/m2,4.28mg/m2.大风条件下,水体氨氮浓度... 详细信息

采用Y型旋浆式沉积物再悬浮装置研究了不同风速下太湖水生植被区沉积物的再悬浮和沉降过程.结果表明,中、小风过程中,随悬浮物浓度的增大,水体氨氮和磷酸盐浓度均显著增加,最大通量分别为0.063g/m2,4.28mg/m2.大风条件下,水体氨氮浓度出现减小趋势,最大通量为-0.027g/m2;磷酸盐浓度的增量相对于小风较小,最大释放量为1.52mg/m2.沉降阶段的最初2h是水体悬浮物浓度恢复的主要阶段,悬浮物浓度平均下降约46%.沉降8h之后,水体悬浮物及营养盐浓度基本恢复至风浪前初始水平,3种风速的氨氮和磷酸根磷的最大释放量仅为0.030g/m2,0.90mg/m2.与藻型湖区营养盐动态负荷结果相比,草型湖区的水体营养盐动态负荷变化相对较小.

关键词：沉积物再悬浮 Y型装置沉降营养盐水生植物太湖

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Link between mutations in ACVRL1 and PLA2G4A genes and chronic intestinal ulcers:A case report and review of literature

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 932-943页

作者： Yong-Jing Tang Jian Zhang Jie Wang Ren-Dong Tian Wei-Wei Zhong ben-sheng Yao Bing-Yu Hou Ying-Hua Chen Wei He Yi-Huai He Department of Infectious Diseases The Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina Department of Gastroenterology Dafang County People's HospitalBijie 551600Guizhou ProvinceChina Department of Internal Medicine Puchang BranchMedical CommunitySuiyang County People's HospitalZunyi 563300Guizhou ProvinceChina Department of Infectious Diseases Jingmen Central HospitalJingmen 448000Hubei ProvinceChina Department of Infectious Diseases Dafang County People's HospitalBijie 551600Guizhou ProvinceChina

BACKGROUND Genetic factors of chronic intestinal ulcers are increasingly garnering *** present a case of chronic intestinal ulcers and bleeding associated with mu-tations of the activin A receptor type II-like 1(ACVRL1)and phospholipase A2 group IVA(PLA2G4A)genes and review the available relevant *** SUMMARY A 20-year-old man was admitted to our center with a 6-year history of recurrent abdominal pain,diarrhea,and dark *** the onset 6 years ago,the patient had received treatment at a local hospital for abdominal pain persisting for 7 d,under the diagnosis of diffuse peritonitis,acute gangrenous appendicitis with perforation,adhesive intestinal obstruction,and pelvic *** surgical treat-ment included exploratory laparotomy,appendectomy,intestinal adhesiolysis,and pelvic abscess *** patient’s condition improved and he was ***,the recurrent episodes of abdominal pain and passage of black stools started again one year after *** the basis of these features and results of subsequent colonoscopy,the clinical diagnosis was established as in-flammatory bowel disease(IBD).Accordingly,aminosalicylic acid,immunotherapy,and related symptomatic treatment were administered,but the symptoms of the patient did not improve *** investigations revealed mutations in the ACVRL1 and PLA2G4A ***1 and PLA2G4A are involved in angiogenesis and coagulation,*** suggests that the chronic intestinal ulcers and bleeding in this case may be linked to mutations in the ACVRL1 and PLA2G4A *** Kangfuxin liquid was administered to promote healing of the intestinal mucosa and effectively manage clinical *** Mutations in the ACVRL1 and PLA2G4A genes may be one of the causes of chronic intestinal ulcers and bleeding in *** administered Kangfuxin liquid may have therapeutic potential.

关键词： Intestinal ulcers Crohn’s disease Ulcerative colitis Activin A receptor type II-like 1 Phospholipase A2 group 4A Case report

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生物质碳对土壤中微囊藻毒素生物有效性的影响

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中国环境科学 2020年第12期40卷 5444-5450页

作者：操庆刘伟京顾毓蓉谢丽强尤本胜姜伟立杨柳燕南京大学环境学院污染控制与资源化研究国家重点实验室江苏南京210023 江苏省环境科学研究院江苏省环境工程重点实验室江苏南京210036 中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室江苏南京210008

通过向土壤中添加水稻秸秆生物质碳(RSB)、玉米秸秆生物质碳(MSB)和鸡粪生物炭(CMB)来减少微囊藻毒素-LR(MC-LR)在生菜中的富集.结果表明,RSB、MSB和CMB在添加量为2%时,生菜叶片中MC-LR含量较空白分别降低了58.0%、49.5%和70.4%,使得每... 详细信息

通过向土壤中添加水稻秸秆生物质碳(RSB)、玉米秸秆生物质碳(MSB)和鸡粪生物炭(CMB)来减少微囊藻毒素-LR(MC-LR)在生菜中的富集.结果表明,RSB、MSB和CMB在添加量为2%时,生菜叶片中MC-LR含量较空白分别降低了58.0%、49.5%和70.4%,使得每日估计摄入量降低到WHO的每日允许摄入量限值以下.CMB显著降低了土壤中MC-LR的总含量,而其他处理则无显著影响.3种生物质碳均显著降低了有效态MC-LR含量,且生菜根系和叶片中MC-LR的含量与土壤MC-LR有效态含量均呈显著正相关关系.所有添加生物质碳处理均对生菜生长无负面影响.

关键词：生物质碳微囊藻毒素生物富集生物有效性土壤-作物系统

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