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Characterization of the archaeal community fouling a membrane bioreactor

Journal of environmental sciences 2015年第3期27卷 115-123页

作者： Jinxue Luo Jinsong Zhang Xiaohui Tan Diane McDougald Guoqiang Zhuang Anthony G.Fane Staffan Kjelleberg Yehuda Cohen Scott A.Rice Key Laboratory of environmental Biotechnology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences School of Biological sciences Nanyang Technological University Advanced environmental Biotechnology Centre Nanyang Environment and Water Research Institute Nanyang Technological University Singapore Membrane Technology Centre Nanyang Environment and Water Research Institute Nanyang Technological University Centre for Marine Bio-Innovation School of Biotechnology and Biomolecular Sciences The University of New South Wales Singapore Centre on environmental Life sciences Engineering Nanyang Technological University

Biofilm formation, one of the primary causes of biofouling, results in reduced membrane flux or increased transmembrane pressure and thus represents a major impediment to the wider implementation of membrane bioreactor （MBR） technologies for water purification. Most studies have focused on the role of bacteria in membrane fouling as they are the most dominant and best studied organisms present in the MBR. In contrast, there is limited information on the role of the archaeal community in biofilm formation in MBRs. This study investigated the composition of the archaeal community during the process of biofouling in an MBR. The archaeal community was observed to have lower richness and diversity in the biofilm than the sludge during the establishment ofbiofilms at low transmembrane pressure （TMP）. Clustering of the communities based on the Bray-Curtis similarity matrix indicated that a subset of the sludge archaeal community formed the initial biofilms. The archaeal community in the biofilm was mainly composed of Thermoprotei, Thermoplasmata, Thermococci, Methanopyri, Methanomicrobia and Halobacteria. Among them, the Thermoprotei and Thermoplasmata were present at higher relative proportions in the biofilms than they were in the sludge. Additionally, the Thermoprotei, Thermoplasmata and Thermococci were the dominant organisms detected in the initial biofilms at low TMP, while as the TMP increased, the Methanopyri, Methanomicrobia, Aciduliprofundum and Halobacteria were present at higher abundances in the biofilms at high TMP.

关键词： Biofouling Biofilm formation Biofilm microbial community Archaeal community Membrane bioreactor

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Effect of Cu on Microstructures of Manganese Steel by EDXA and SEM

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Journal of Materials Science & Technology 2007年第3期23卷 307-311页

作者： Xinhua CHEN Junhua DONG Enhou HAN Wei KE environmental Corrosion Center Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

In order to investigate the distribution of Cu and Mg, and the effect of Cu on the microstructure of steels, manganese steels containing various Cu contents were annealed at 1260, 1100 and 1000℃, respectively, for I h and subsequently cooled to room temperature in the furnace to simulate the pre-rolling anneal. The results indicate that Cu is not microscopically segregated in the annealed steels. The scanning electron microscopy （SEM） observation shows that the main microstructure consist of ferrite and pearlite; the percentage of pearlite in the steels increases with increasing Cu content. The grain size reduces with the decrease of the annealing temperature. The results of energy dispersive X-ray analysis （EDXA） suggest that Cu content in pearlite is higher than that in ferrite, demonstrating that the microstructure-segregation of Cu occurred. However, the cast specimens show that Cu content in MnS and S-rich phases is high. In addition, Cu of 0.2%-0.4% could improve the distribution of MnS and S-rich inclusions. The optimal Cu content in steels and the optimal annealing temperature between 1100-1200℃ were determined.

关键词： Manganese steels Copper-alloying Annealing Energy dispersive X-ray analysis (EDXA) Scanning electron microscopy (SEM)

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Comprehensive evaluation of heavy metal contamination of sediment in Lake Dianchi by using modified AHP method and ^(137)Cs dating

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Frontiers of environmental Science & Engineering 2008年第3期2卷 370-379页

作者： Yan ZHANG Xiang GAO Zhenyu ZHONG Xihai DENG Buzhuo PENG School of Geographic and Oceanographic sciences Nanjing UniversityNanjing 210093China State Key Laboratory of Soil Sustainable Agriculture Institute of Soil SciencesChinese Academy of SciencesNanjing 210008China

Through the use of general sampling and measurement by ^(137)Cs dating,problems regarding the absence of monitoring data can easily be ***,weighted values need to be determined while Environment Quality Comprehensive Index(EQCI)is commonly used as applied in environmental quality comprehensive *** order to overcome the subjectivity in determining weights,the modified Analytical Hierarchy Process(AHP)method was *** modified AHP method involved the following key procedures:First,the parameters y_(i1) and y_(i2) were calculated based on the monitoring data;second,the factors were put in order according to the symbol and value of y_(i1) and y_(i2);third,the continuous odd integers,which represented the importance of factors,were given to factors according to their seating order;and,fourth,the factor weights were determined from the pair-wise comparison matrix calculated by the ratio of the given odd ***,the weights were completely based on the monitoring *** the present study,the comprehensive quality of sediments in five sections of Lake Dianchi were evaluated and the results indicated that the current contamination of sediments in each lake section is much more serious than at any other time in history.

关键词： ^(137)Cs dating modified AHP method environment quality comprehensive evaluation heavy metal contamination of sediment Lake Dianchi

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Enhanced production of poly-γ-glutamic acid via optimizing the expression cassette of Vitreoscilla hemoglobin in Bacillus licheniformis

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Synthetic and Systems Biotechnology 2022年第1期7卷 567-573页

作者： Qing Zhang Yaozhong Chen Lin Gao Jian’gang Chen Xin Ma Dongbo Cai Dong Wang Shouwen Chen State Key Laboratory of Biocatalysis and Enzyme Engineering Environmental Microbial Technology Center of Hubei ProvinceCollege of Life SciencesHubei UniversityWuhan430062PR China Wuhan Junan Biotechnology Co.Ltd. WuhanChina Tobacco Research institute Chinese Academy of Agricultural SciencesQingdaoChina

Poly-γ-glutamic acid(γ-PGA)is a natural polymer with various applications,and its high-viscosity hinders ox-ygen transmission and improvement of synthesis *** hemoglobin(VHB)has been introduced into various hosts as oxygen carrier,however,its expression strength and contact efficiency with oxygen hindered efficient oxygen transfer and metabolite ***,we want to optimize the expression cassette of VHB for γ-PGA ***,our results implied that γ-PGA yields were enhanced when introducing twin-arginine translocation(Tat)signal peptides(SP_(YwbN),SP_(PhoD) and SP_(TorA))into VHB expression cassette,and the best per-formance was attained by SP YwbN from Bacillus subtilis,theγ-PGA yield of which was 18.53% higher than that of control strain,and intracellular ATP content and oxygen transfer coefficient(K_(L)a)were increased by 29.71% and 73.12%,respectively,indicating that VHB mediated by SP YwbN benefited oxygen transfer and ATP generation forγ-PGA ***,four promoters were screened,and P vgb was proven as the more suitable promoter for VHB expression andγ-PGA synthesis,andγ-PGA yield of attaining strain WX/pPvgb-YwbN-Vgb was further increased to 40.59 g/L by 10.18%.Finally,WX/pPvgb-YwbN-Vgb was cultivated in 3 L fermentor for fed-batch fermentation,and 46.39 g/Lγ-PGA was attained by glucose feeding,increased by 49.26%compared with the initial yield(31.01 g/L).Taken together,this study has attained an efficient VHB expression cassette for oxygen transfer andγ-PGA synthesis,which could also be applied in the production of other metabolites.

关键词： Vitreoscilla hemoglobin Expression element Twin-arginine translocation Poly-γ-glutamic acid Bacillus licheniformis

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Stabilization treatment of contaminated soil:a field-scale application in Shanghai,China

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Frontiers of environmental Science & Engineering 2010年第4期4卷 395-404页

作者： Changbo ZHANG Qishi LUO Chunnu GENG Zhongyuan LI institute of Wastes and Soil Environment Shanghai Academy of Environmental SciencesShanghai 200233China

Stabilization is one of the best demonstrated available technologies for treating toxic pollutants in soils and has been used worldwide but is rarely used for treatment of contaminated sites in China despite many bench-scale ***,a field-scale application of stabilization treatment in Shanghai,China was summarized to demonstrate the whole engineering process and the key technical issues regarding stabilization of contaminated soil.A site contaminated with arsenic(As)and polycyclic aromatic hydrocarbons(PAHs),formerly used as a lighting plant in Shanghai,was chosen as the demonstration *** measures were taken to treat the contaminated soil to reuse the site for residential *** whole engineering remediation process consisted of phase I environmental site assessment(ESA)and phase II ESA,quantitative human health risk assessment,remediation alternatives evaluation,benchscale testing,remedial design,engineering implementation,and post-remediation assessment.A third party conducted evaluation monitoring indicated desirable results were achieved via the stabilization *** addition,some technical obstacles related to soil stabilization treatment were discussed,including soil quality evaluation,stabilization effectiveness validation,and soil reuse assessment.

关键词： stabilization contaminated soil field-scale demonstration technical obstacles

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Nestedness of waterbird assemblages in the subsidence wetlands recently created by underground coal mining

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Current Zoology 2019年第2期65卷 155-163页

作者： Chunlin LI Binbin ZHAO Yanping WANG School of Resources and environmental Engineering Anhui University Hefei 230601 China Jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life Sciences Nanjing Normal University Nanjing 210023 China College of Life sciences Zhejiang University Hangzhou 310058 China

Nestedness has been a research focus in fields of island biogeography and community ecology in recent decades. Although nestedness of faunal assemblages has been investigated in natural wetlands, it remains largely unknown whether and why waterbird communities in artificial wetlands follow n ested patter ns. We exami ned the existence of n ested ness and un derlyi ng drivers in waterbird comm un ities in subside nee wetlands that are recently created by large-scale un derground coal mining in the North China Plain. Twelve point-count surveys for waterbirds were undertaken approximately every 2 weeks in 55 subside nee wetla nds from September 2016 to April 2017. We used the metric WNODF to estimate nestedness of the assemblages. Partial Spearman rank correlations were performed to examine the association between the nestedness and habitat variables (wetland area, landscape connectivity, wetland age, and habitat diversity) as well as life-history traits (body size, clutch size, dispersal ratio, geographical range size, and migrant status) related to species exti notion risk and colon izati on rate. Waterbird assemblages in the subside nee wetla nds were significantly nested. After controlling for other independent variables, the magnitude of nestedness was significantly and negatively correlated with wetland area and species trait linked to extinction risk (i.e., geographical range size). Our results indicate that selective extinction may be the main driver of the nestedness of waterbird assemblages in our study system. However, the nestedness was not due to passive sampling, selective colonization, or habitat diversity. From a conservation viewpoint, both large wetlands and waterbirds with a small geographic range should be protected to maximize the preserved species richness.

关键词： geographical range size nested pattern selective extinction waterbirds WNODF

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Upcycling biomass waste into Fe single atom catalysts for pollutant control

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Journal of Energy Chemistry 2022年第6期31卷 282-291,I0008页

作者： Xin Li Kang Hu Yizhe Huang Qingqing Gu Yuwen Chen Bing Yang Rongliang Qiu Wenhao Luo Bert M.Weckhuysen Kai Yan Guangdong Provincial Key Laboratory of environmental Pollution Control and Remediation Technology School of Environmental Science and EngineeringSun Yat-Sen UniversityGuangzhou 510275GuangdongChina CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina College of Natural Resources and Environment South China Agricultural UniversityGuangzhou 510275GuangdongChina Inorganic Chemistry and Catalysis Group Debye Institute for Nanomaterials ScienceUtrecht UniversityUtrecht 3584 CGNetherlands

Contaminants of heavy metals and antibiotics, which are frequently detected in water, soil and food chains with increasing prevalence in our current society, can cause potential harm to human health and disrupt human ecosystem irreversibly. Herein, we have successfully utilized biomass waste ferns contaminated by iron mines, to fabricate a first-of-its-kind high-performance class of Fe single-atom catalysts(FeSAC) by a facile pyrolysis. The optimal FeSAC-800 shows an excellent efficiency in the fastphotocatalytic degradation of six types of quinolone antibiotics(e.g., norfloxacin, levofloxacin, ciprofloxacin, enrofloxacin, lomefloxacin, flumequine) in 1 h under the simulated natural light irradiation. Based on advanced characterization, a well-defined structure of FeN_(4), confined in the porous carbon is elaborated for the FeSAC-800. Mechanism of the photodegradation is via a Fenton-like oxidation process whereas the reactive oxygen species play a key role. These findings open a new avenue for efficient, sustainable utilization of biomass waste in pollutant control.

关键词： Single-atom catalysts Photocatalysis Biomass waste Quinolone antibiotics Sustainability

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Drivers of Regional environmental Pollution Load and Zoning Control:A Case Study of the Yangtze River Economic Belt,China

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Chinese Geographical Science 2022年第1期32卷 31-48页

作者： ZHOU Kan WU Jianxiong FAN Jie LIU Hanchu Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China institute of Science and Development Chinese Academy of SciencesBeijing 100190China

The high environmental pollution load caused by the massive pollutant emissions and the accumulation of endogenous and cross-regional pollution has become an important obstacle to the current ecological civilization construction in the Yangtze River Economic Belt(YREB)in *** the YREB as an example,by using four environmental pollutant emission indicators,including chemical oxygen demand(COD),ammonia nitrogen(NH_(3)-N),sulfur dioxide(SO_(2)),and nitrogen oxides(NO_(x)),this paper established an environmental pollution load index(EPLI)based on the entropy-based ***,the Spatial Durbin Model was used to quantitatively analyze the drivers and spatial effects of environmental pollution ***,specific scientific references were provided for formulating environmental regulations of pollution source control in the *** results showed that:1)During2011-2015,the EPLI in the YREB was reduced significantly and the environmental pollution load increased from upstream to *** them,the pollution load levels in the Upper Mainstream subbasin,Taihu Lake subbasin,and Lower Mainstream subbasin were the most prominent.2)The environmental pollution load situation in the YREB was generally stable and partially *** load level areas were mainly concentrated in the Yangtze River Delta Region and the provincial borders in upstream,midstream,and downstream *** high load level areas already formed in Chengdu and Chongqing were also the key regulatory points in the future.3)The degree of local environmental pollution load was apparently affected by the adjacent *** population size,industrialization level,and the fiscal decentralization not only drove the increase of the local environmental pollution load level,but also affected the adjacent areas through the spatial spillover *** land development intensity mainly drove the increase in the local EPLI in the *** factors such as economic development level and agri

关键词： environmental pollution load drivers spatial effects Spatial Durbin Model Yangtze River Economic Belt

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Interpretation of residual gravity anomaly caused by simple shaped bodies using very fast simulated annealing global optimization

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Geoscience Frontiers 2015年第6期6卷 875-893页

作者： Arkoprovo Biswas Department of Earth and environmental sciences Indian Institute of Science Education and Research(IISER) Bhopal

A very fast simulated annealing（VFSA） global optimization is used to interpret residual gravity ***,VFSA optimization yields a large number of best-fitted models in a vast model space;the nature of uncertainty in the interpretation is also examined simultaneously in the present *** results of VFSA optimization reveal that various parameters show a number of equivalent solutions when shape of the target body is not known and shape factor ＇q＇ is also optimized together with other model *** study reveals that amplitude coefficient k is strongly dependent on shape *** shows that there is a multi-model type uncertainty between these two model parameters derived from the analysis of ***,the appraised values of shape factor from various VFSA runs clearly indicate whether the subsurface structure is sphere,horizontal or vertical cylinder type ***,the exact shape factor（1.5 for sphere,1.0 for horizontal cylinder and 0.5 for vertical cylinder）is fixed and optimization process is *** fixing the shape factor,analysis of uncertainty and cross-plots shows a well-defined uni-model *** mean model computed after fixing the shape factor gives the utmost consistent *** of noise-free and noisy synthetic data as well as field data demonstrates the efficacy of the approach.

关键词： Gravity anomaly Idealized body Uncertainty VFSA Subsurface structure Ore exploration

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A dopamine and noradrenaline reuptake inhibitor （bupropion） does not alter exercise performance of bank voles

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Current Zoology 2016年第3期62卷 307-315页

作者： Ewa JAROMIN Edyta Teresa SADOWSKA Pawet KOTEJA institute of environmental sciences Jagiellonian University Gronostajowa 7 Krakow 30-387 Poland

Physical performance is determined both by biophysical and physiological limitations and behavioral characteristic, specifically motivation. We applied an experimental evolution approach combined with pharmacological manipulation to test the hypothesis that evolution of increased aerobic exercise performance can be triggered by evolution of motivation to undertake physical activity. We used a unique model system: bank voles from A lines, selected for high swim-induced aerobic metabolism (VOswim), which achieved a 61% higher mass-adjusted VOswim than those from unselected C lines. Because the voles could float on the water surface with only a minimum activity, the maximum rate of metabolism achieved in that test depended not only on their aerobic capacity, but also on motivation to undertake intensive activity. Therefore, we hypothesized that signaling of neurotransmitters putatively involved in regulating physical activity (dopamine and noradrenaline) had changed in response to selection. We measured VOswim after intraperitoneal injections of saline or the norepinephrine and dopamine reuptake inhibitor bupropion (20 mg/kg or 30 mg/kg). Additionally, we measured forced-exercise VO (VOmax). In C lines, VOswim (mass-adjusted mean ± standard error (): 4.0 ± 0.1 mLO/min) was lower than VOmax (5.0 ± 0.1 mLO/min), but in A lines VO2swim (6.0 ± 0.1 mLO/min) was as high as VOmax (6.0 ± 0.1 mLO/min). Thus, the selection effectively changed both the physiological-physical performance limit and mechanisms responsible for the willingness to undertake vigorous locomotor activity. Surprisingly, the drug had no effect on the achieved level of VOswim. Thus, the results did not allow firm conclusions concerning involvement of these neurotransmitters in evolution of increased aerobic exercise performance in the experimental evolution model system.

关键词：去甲肾上腺素盐酸安非他酮运动性能多巴胺抑制剂田鼠银行摄取

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