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Journal of Environmental Sciences 2014年第3期26卷 566-574页

作者： yongmei li Xianzhong Cao lin Wang State Key Laboratory of Pollution Control and Resource Reuse Tongji University Henan Institute of Metallurgy Henan Academy of Science

N,N-Dimethyldithiocarbamate （DMDTC） is a typical precursor of N-nitrosodimethylamine （NDMA）. Based on separate hydrolysis, sorption and biodegradation studies of DMDTC, a laboratory-scale anaerobic-anoxic-oxic （AAO） system was established to investigate the removal mechanism of DMDTC in this nutrient removal biological treatment system. DMDTC hydrolyzed easily in water solution under either acidic conditions or strong alkaline conditions, and dimethylamine （DMA） was the main hydrolysate. Under anaerobic, anoxic or oxic conditions, DMDTC was biodegraded and completely mineralized. Furthermore, DMA was the main intermediate in DMDTC biodegradation. In the AAO system, the optimal conditions for both nutrient and DMDTC removal were hydraulic retention time 8 hr, sludge retention time 20 day, mixed-liquor return ratio 3：1 and sludge return ratio 1：1. Under these conditions, the removal efficiency of DMDTC reached 99.5%; the removal efficiencies of chemical organic demand, ammonium nitrogen, total nitrogen and total phosphorus were 90%, 98%, 81% and 93%, respectively. Biodegradation is the dominant mechanism for DMDTC removal in the AAO system, which was elucidated as consisting of two steps： first, DMDTC is transformed to DMA in the anaerobic and anoxic units, and then DMA is mineralized to CO2 and NH3 in the anoxic and oxic units. The mineralization of DMDTC in the biological treatment system can effectively avoid the formation of NDMA during subsequent disinfection processes.

关键词： N,N-dimethyldithioc arbamate hydrolysis biodegradation aerobic processes anaerobic processes wastewater treatment

Characterization of N-nitrosodimethylamine formation from the ozonation of ranitidine

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Journal of Environmental Sciences 2017年第8期29卷 116-126页

作者： Juan Lv lin Wang yongmei li School of Environment and Architecture University of Shanghai for Science and Technology State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji University

N-nitrosodimethylamine（NDMA） is an emerging disinfection by-product which is formed during water disinfection in the presence of amine-based precursors. Ranitidine, as one kind of amine-based pharmaceuticals, has been identified as NDMA precursor with high NDMA molar conversion during chloramination. This study focused on the characterization of NDMA formation during ozonation of ranitidine. Influences of operational variables（ozone dose, pH value） and water matrix on NDMA generation as well as ranitidine degradation were evaluated. The results indicate high reactivity of ranitidine with ozone.Dimethylamine（DMA） and NDMA were generated due to ranitidine oxidation. High pH value caused more NDMA accumulation. NDMA formation was inhibited under acid conditions（pH ≤ 5） mainly due to the protonation of amines. Water matrix such as HCO-3and humic acid impacted NDMA generation due to UOH scavenging. Compared with UOH,ozone molecules dominated the productions of DMA and NDMA. However, UOH was a critical factor in NDMA degradation. Transformation products of ranitidine during ozonation were identified using gas chromatography–mass spectrometry. Among these products, just DMA and N,N-dimethylformamide could contribute to NDMA formation due to the DMA group in the molecular structures. The NDMA formation pathway from ranitidine ozonation was also proposed.

关键词： Ranitidine N-nitrosodimethylamine（NDMA） Ozone Influencing factor NDMA formation pathway

Biodegradation of 2-methylquinoline by Enterobacter aerogenes TJ-D isolated from activated sludge

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Journal of Environmental Sciences 2013年第7期25卷 1310-1318页

作者： lin Wang yongmei li Jingyuan Duan State Key Laboratory of Pollution Control and Resource Reuse Tongji University

Bacterial strain Enterobacter aerogenes TJ-D capable of utilizing 2-methylquinoline as the sole carbon and energy source was isolated from acclimated activated sludge under denitrifying conditions. The ability to degrade 2-methylquinoline by E. aerogenes TJ-D was investigated under denitrifying conditions. Under optimal conditions of temperature （35°C） and initial pH 7, 2-methylquinoline of 100 mg/L was degraded within 176 hr. The degradation of 2-methylquinoline by E. aerogenes TJ-D could be well described by the Haldane model （R 2 〉 0.91）. During the degradation period of 2-methylquinoline （initial concentration 100 mg/L）, nitrate was almost completely consumed （the removal efficiency was 98.5%）, while nitrite remained at low concentration （〈 0.62 mg/L） during the whole denitrification period. 1,2,3,4-Tetrahydro-2-methylquinoline, 4-ethyl-benzenamine, N-butyl-benzenamine, N-ethyl-benzenamine and 2,6-diethyl-benzenamine were metabolites produced during the degradation. The degradation pathway of 2-methylquinoline by E. aerogenes TJ-D was proposed. 2-Methylquinoline is initially hydroxylated at C-4 to form 2-methyl-4-hydroxy-quinoline, and then forms 2-methyl-4-quinolinol as a result of tautomerism. Hydrogenation of the heterocyclic ring at positions 2 and 3 produces 2,3-dihydro-2-methyl-4-quinolinol. The carbon-carbon bond at position 2 and 3 in the heterocyclic ring may cleave and form 2-ethyl-N-ethyl-benzenamine. Tautomerism may result in the formation of 2,6-diethyl-benzenamine and N-butyl-benzenamine. 4- Ethyl-benzenamine and N-ethyl-benzenamine were produced as a result of losing one ethyl group from the above molecules.

关键词： biodegradation Enterobacter aerogenes TJ-D 2-methylquinoline denitrifying conditions activated sludge

Distribution and seasonal variation of estrogenic endocrine disrupting compounds,N-nitrosodimethylamine, and N-nitrosodimethylamine formation potential in the Huangpu River, China

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Journal of Environmental Sciences 2014年第5期26卷 1023-1033页

作者： Ai Zhang yongmei li ling Chen State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and Engineering Tongji University

Detection of estrogenic endocrine disrupting compounds （EDCs） and N-nitrosodimethylamine （NDMA） in drinking water has led to rising concerns. There are, however, a paucity of studies on the distribution and seasonal variation of NDMA and NDMA formation potential （NDMA-FP） in natural waters, especially in China. For EDCs, limited studies have investigated the distribution and seasonal variation of estrone （El）, 1713-estradiol （E2）, estriol （E3）, 17a-ethinylestradiol （EE2）, technical-nonylphenols （t-NP）, and bisphenol A （BPA） in Shanghai. In this study, water samples were collected from 11 sampling sites along the Huangpu River in 2012. The distribution and seasonal variation of EDCs, NDMA, and NDMA-FP were investigated. The results showed that all of the 11 sampling sites were contaminated by the target compounds. Compared with E2 and EE2, higher E1 and E3 concentrations were usually detected in the Huangpu River. The values of 17β- estradiol equivalents （EEQ） suggest a high possibility of endocrine effects on exposed organisms in the Huangpu River. NDMA-FP and t-NP were the dominant contaminants among the eight target compounds. The detection rates of the target compounds and their concentrations were both higher in dry seasons than in wet seasons. Higher concentrations of target compounds were observed in urban sampling sites near drainage outlets, and also in suburban sampling sites where intensive livestock farming and farmlands were located.

关键词： EDCs NDMA NDMA-FP seasonal variation spatial distribution

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高强钢筋超高性能混凝土框架结构易损性分析

哈尔滨工程大学学报 2024年第3期45卷 572-580页

作者：贺少锋邓宗才李永梅北京工业大学城市与工程安全减灾省部共建教育部重点实验室北京100124

为了研究高强钢筋超高性能混凝土(ultra-high performance concrete, UHPC)结构的抗震能力,本文选取了8条地震动分别对普通钢筋混凝土框架结构(模型Frame-C)和高强钢筋UHPC框架结构(模型Frame-UHPC)进行了增量动力分析,分别以最大层间... 详细信息

为了研究高强钢筋超高性能混凝土(ultra-high performance concrete, UHPC)结构的抗震能力,本文选取了8条地震动分别对普通钢筋混凝土框架结构(模型Frame-C)和高强钢筋UHPC框架结构(模型Frame-UHPC)进行了增量动力分析,分别以最大层间位移角和谱加速度为结构需求参数和地震动强度参数,拟合出概率地震需求模型,进而计算出2个模型的地震易损性曲线,得到了结构的风险预测和损伤评估结果。研究结果表明:规范性态点下,相较于模型Frame-C,模型Frame-UHPC达到最大中等破坏或严重破坏状态概率时所对应的地震动强度更大,表明模型Frame-UHPC在强震作用下具有更好的抗震能力;小震作用下,模型Frame-UHPC的易损性指数明显小于模型Frame-C,体现了高强钢筋UHPC结构的高强优势。当使用规范性态点时,2个模型在中震和大震作用下的易损性指数相差较小,模型Frame-UHPC不能充分发挥UHPC和高强钢筋的材料优势。通过对文献中配筋UHPC柱数据整理分析,给出了适用于模型Frame-UHPC的建议性态点。与规范性态点相比,建议性态点下模型Frame-UHPC达到极限状态的概率更低,易损性指数也明显减小,小震和中震所应对的易损性指数分别减小了19.5%和42.3%,模型Frame-UHPC在建议性态点下可以更好地发挥其材料优势。

关键词：超高性能混凝土高强钢筋易损性分析增量动力分析抗震能力破坏状态易损性指数性态点

微生物矿化去除地浸采铀地下水中污染物的试验研究

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核技术 2024年第6期47卷 35-44页

作者：贺桂成朱小裕李咏梅南华大学资源环境与安全工程学院衡阳421001

微生物诱导碳酸钙沉淀(Microbial-induced Calcium Carbonate Precipitation,MICP)技术能较好地矿化去除地下水中的污染物。本文选用巴氏芽孢杆菌,分析其耐酸性以及对铀的耐受性,探究初始U(Ⅵ)浓度、Ca^(2+)浓度、pH值、菌液浓度和矿化... 详细信息

微生物诱导碳酸钙沉淀(Microbial-induced Calcium Carbonate Precipitation,MICP)技术能较好地矿化去除地下水中的污染物。本文选用巴氏芽孢杆菌,分析其耐酸性以及对铀的耐受性,探究初始U(Ⅵ)浓度、Ca^(2+)浓度、pH值、菌液浓度和矿化作用时间等因素对MICP去除污染物的影响,揭示MICP矿化去污的机理。研究结果表明:巴氏芽孢杆菌在pH为4时具有较好的脲酶活性,可以适应含U(Ⅵ)浓度为100 mg·L^(-1)的地下水;当初始pH为4、铀浓度为50 mg·L^(-1)、Ca^(2+)浓度为8000 mg·L^(-1)、MICP矿化作用时间为48 h时,地下水中的U(Ⅵ)的去除率为61%、钙去除率为54%,但当初始pH升高到7时,U(Ⅵ)的去除率增加到91%。Ca^(2+)浓度的升高有助于MICP矿化去除地下水中的U(Ⅵ),但Ca2+浓度过高时其自身的被去除率相对较低。MICP矿化产物的成分为含铀的碳酸钙,其中,铀主要以共沉淀的方式被固定。

关键词：微生物矿化地浸采铀地下水铀污染物

Waste activated sludge hydrolysis and acidification： A comparison between sodium hydroxide and steel slag addition

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Journal of Environmental Sciences 2016年第10期28卷 200-208页

作者： Ying Zhang Chaojie Zhang Xuan Zhang Leiyu Feng yongmei li Qi Zhou State Key Laboratory of Pollution Control and Resources Reuse School of Environmental Science and Engineering Tongji University Shanghai 200092 China School of Civil Mining and Environmental Engineering Faculty of Engineering and Information Sciences University of Wollongong NSW 2522 Australia East China Electric Power Design Institute Co. Ltd. of China Power Engineering Consulting Group Shanghai 200063 China

Alkaline treatment with steel slag and NaOH addition were investigated under different pH conditions for the fermentation of waste activated sludge. Better performance was achieved in steel slag addition scenarios for both sludge hydrolysis and acidification. More solubilization of organic matters and much production of higher VFA （volatile fatty acid） in a shorter time can be achieved at pH 10 when adjusted by steel slag. Higher enzyme activities were also observed in steel slag addition scenarios under the same pH conditions. Phosphorus concentration in the supematant increased with fermentation time and pH in NaOH addition scenarios, while in contrast most phosphorus was released and captured by steel slag simultaneously in steel slag addition scenarios. These results suggest that steel slag can be used as a substitute for NaOH in sludge alkaline treatment.

关键词： Waste activated sludgeAlkaline treatmentSteel slagSodium hydroxide

Pioneer to exploration and construction of Jilin Province s higher medical laboratory education and talent training system

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Protein & Cell 2020年第11期11卷 783-785页

作者： Huiming Han Xichao Han Sainan Wu Baihui lin Xu Cheng Qinlong Hou yongmei li Medical College Beihua UniversityJilin 132013China The Center for Infection and immunity Beihua UniversityJilin 132013China The School of life Sciences Jilin UniversityChangchun 130012China

Professor Tingbin Yang(杨廷彬)has dedicated his whole life to education science and microbiology research.He is not only an excellent microbiologist but also an outstanding educator.He has finished many professional books and got several honors for his job.Prof.Yang has contributed a lot for the development of medical laboratory education in China and clinical medicine.

关键词： education Pioneer finished

典型植物根系对紫色土化学属性和化学蚀变指数的影响

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土壤 2024年第2期56卷 425-432页

作者：李雪李春培李永梅范茂攀赵吉霞云南农业大学资源与环境学院昆明650201

为探究植物根系形态对紫色土风化的影响,以云南元谋干热河谷区典型植被(锥连栎、华西小石积、牛筋草和裸地)覆盖条件下的紫色土为研究对象,研究了不同植被类型根系在不同土层的分布特征及其对各土层养分含量和化学蚀变指数(CAI)的影响... 详细信息

为探究植物根系形态对紫色土风化的影响,以云南元谋干热河谷区典型植被(锥连栎、华西小石积、牛筋草和裸地)覆盖条件下的紫色土为研究对象,研究了不同植被类型根系在不同土层的分布特征及其对各土层养分含量和化学蚀变指数(CAI)的影响。结果表明:裸地、乔木、灌木、草本覆盖下紫色土化学蚀变指数分别为73.98~78.87、78.53~84.68、77.89~82.18、77.91~81.04,且均表现为随土层深度增加而降低。各植被的根系均集中分布于0~20 cm土层,不同植物根系体积存在明显差异,乔木、草本和灌木覆盖下的根系体积与裸地相比分别增加145.17%、144.78%、74.98%,乔木、灌木和草本的根系表面积与裸地相比分别增加651.16%、610.79%、181.62%。土壤中养分含量随土层深度的增加而降低。随着土层深度的增加,有机质、碱解氮、有效磷和速效钾含量呈降低趋势,裸地和乔木覆盖下的pH呈增加趋势,而草本和灌木覆盖下的pH则呈相反趋势。相关性分析结果表明,土壤的CAI值与土壤有机质、碱解氮含量呈显著正相关(P<0.05),相关系数高达0.520、0.591;土壤p H、有效磷含量与土壤CAI值呈显著负相关(P<0.05),土壤CAI值与根系体积、根系表面积呈极显著正相关(P<0.01),相关系数高达0.693、0.621。综上,植物根系对于土壤的化学风化具有较明显的促进作用。

关键词：植被类型根系形态土壤养分化学蚀变指数(CAI) 紫色土

福建省体育产业发展对第三产业就业的影响研究

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黄山学院学报 2024年第3期26卷 86-89页

作者：沈焰焰李勇妹福建船政交通职业学院通识教育学院福建福州350007

通过对2013—2022年福建省体育产业增加值和第三产业就业情况进行数理统计,并进行Logistic建模分析。结果表明福建省体育产业增加值与第三产业就业之间存在正相关,边际分析得出福建体育产业对第三产业就业起明显的促进作用,边际分析和... 详细信息

通过对2013—2022年福建省体育产业增加值和第三产业就业情况进行数理统计,并进行Logistic建模分析。结果表明福建省体育产业增加值与第三产业就业之间存在正相关,边际分析得出福建体育产业对第三产业就业起明显的促进作用,边际分析和拐点分析得出随时间的推移促进作用逐渐减小。最后给出福建省体育产业促进第三产业就业增长的路径,以期为体育产业发展提供科学指导。

关键词：体育产业第三产业就业边际分析拐点分析