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Impacts of n-alkane concentration on soil bacterial community structure and alkane monooxygenase genes abundance during bioremediation processes

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Frontiers of environmental Science & Engineering 2018年第5期12卷 155-167页

作者： Yueqiao Liu Aizhong Ding Yujiao Sun Xuefeng Xia Dayi Zhang College of Water Sciences Beijing Normal UniversityBeijing 100875China School of environment Tsinghua UniversityBeijing 100084China Lancaster environment centre Lancaster UniversityLancaster LA14YQUK

Petroleum hydrocarbons,mainly consisting of n-alkanes and polycyclic aromatic hydrocarbons(PAHs),are considered as priority pollutants and biohazards in the environment,eventually affecting the ecosystem and human *** many previous studies have investigated the change of bacterial community and alkane degraders during the degradation of petroleum hydrocarbons,there is still lack of understanding on the impacts of soil alkane contamination *** the present study,microcosms with different n-alkane contamination(1%,3%and 5%)were set up and our results indicated a complete alkane degradation after 30 and 50 days in 1%-and 3%-alkane treatments,*** all the treatments,alkanes with medium-chain length(C_(11)-C_(14))were preferentially degraded by soil microbes,followed by C27-alkane in 3%and 5%*** contamination level slightly altered soil bacterial community,and the main change was the presence and abundance of dominant alkane ***,Gemmataceae and Thermodesulfovibrionaceae were highly related to the degradation of C_(14)-and C_(27)-alkanes in 5%treatment,but linked to alkanes with medium-chain(C11-C18)in 1%treatment and C21-alkane in 3%treatment,***,we compared the abundance of three alkane-monooxygenase genes,e.g.,alk_A,alk_P and alk_*** abundance of alk_R gene was highest in soils,and alk_P gene was more correlated with alkane degradation efficiency,especially in 5%*** results suggested that alkane contamination level showed non-negligible effects on soil bacterial communities to some extents,and particularly shaped alkane degraders and degrading genes *** study provides a better understanding on the response of alkane degraders and bacterial communities to soil alkane concentrations,which affects their biodegradation process.

关键词： Petroleum hydrocarbon contaminated site n-alkane contamination level n-alkane biodegradation Soil bacterial community Alkane degraders Alkane-monooxygenase genes

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Effects of mechanical activation on the kinetics of terbium leaching from waste phosphors using hydrochloric acid

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Journal of Rare Earths 2017年第4期35卷 398-405页

作者：谭全银邓超李金惠 State Key Joint Laboratory of environment Simulation and Pollution Control School of EnvironmentTsinghua University Beijing 100084China Basel Convention Regional centre for Training and Technology Transfer for Asia and the Pacific Beijing 100084China

The effect of mechanical activation （MA） on the kinetics of terbium （Tb） leaching from waste phosphors using hydrochloric acid was investigated. Leaching kinetics, such as apparent reaction rate, activation energy and reaction order, were determined using the shrinking-core model and the Arrhenius equation. Results obtained from experiments with different concentrations of HC1 and under different leaching temperatures were used for the determinations. The impacts of factors such as rotational speed, HC1 concen- tration and leaching temperature on the leaching rate of Tb were also discussed. The results showed that MA could dramatically increase the leaching rate of Tb from waste phosphors, and the apparent reaction rate （kap） of leaching was accelerated as well. For inactivated waste phosphors, the apparent activation energy （Eap） was 52.82±3.95 kJ/mol, indicating that the rate-controlling step of the leaching process was the chemical reaction. The Eap dropped to 25.96 ±3.90 kJ/mol and 10.96±2.79 k J/tool when the waste phosphors were mechanically activated at rotational speeds of 400 and 600 r/min, respectively; the leaching process transformed to a hybrid （chemical-reaction and diffusion） control process, and even a reagent-diffusion （through the product layer） control process. The apparent reaction order for Tb leaching from 400 r/min-activated waste phosphors was 2.49±0.11, and it decreased to 1. 16±0.17 when the rotational speed of 600 r/min was used. Kinetics results indicated that MA could make Tb leaching occur spontaneously, and thc activation intensity of waste phosphors was strengthened with higher rotational speed.

关键词： terbium mechanical activation waste phosphors leaching kinetics hydrochloric acid rare earths

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Computational simulation of convective flow in the Earth crust under consideration of dynamic crust-mantle interactions

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Journal of Central South University 2011年第6期18卷 2080-2084页

作者：赵崇斌彭省临刘亮明 B.E.HOBBS A.ORD Computational Geosciences Research centre Central South University School of Earth and environment The University of Western Australia

The finite element method was used to solve fluid dynamic interaction problems between the crust and mantle of the Earth. To consider different mechanical behaviours, the lithosphere consisting of the crust and upper mantle was simulated as fluid-saturated porous rocks, while the upper aesthenospheric part of the mantle was simulated as viscous fluids. Since the whole lithosphere was computationally simulated, the dynamic interaction between the crust and the upper mantle was appropriately considered. In particular, the mixing of mantle fluids and crustal fluids was simulated in the corresponding computational model. The related computational simulation results from an example problem demonstrate that the mantle fluids can flow into the crust and mix with the crustal fluids due to the resulting convective flows in the crust-mantle system. Likewise, the crustal fluids can also flow into the upper mantle and mix with the mantle fluids. This kind of fluids mixing and exchange is very important to the better understanding of the governing processes that control the ore body formation and mineralization in the upper crust of the Earth.

关键词： computational simulation crustal fluids mantle fluids fluid dynamic interaction

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Modeling Size-number Distributions of Seeds for Use in Soil Bank Studies

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Journal of Integrative Plant Biology 2008年第5期50卷 531-535页

作者： Hugo Casco Alexandra Soveral Dias Luís Silva Dias Chemical Ecology Unit Centre of Ecology and EnvironmentUniversidade de vora7002-554 vora Portugal

Knowledge of soil seed banks is essential to understand the dynamics of plant populations and communities and would greatly benefit from the integration of existing knowledge on ecological correlations of seed size and shape. The present study aims to establish a feasible and meaningful method to describe size-number distributions of seeds in multi-species situations. For that purpose, size-number distributions of seeds with known length, width and thickness were determined by sequential sieving. The most appropriate combination of sieves and seeds dimensions was established, and the adequacy of the power function and the Weibull model to describe size-number distributions of spherical, non-spherical, and all seeds was investigated. We found that the geometric mean of seed length, width and thickness was the most adequate size estimator, providing shape-independent measures of seeds volume directly related to sieves mesh side, and that both the power function and the Weibull model provide high quality descriptions of size-number distributions of spherical, non-spherical, and all seeds. We also found that, in spite of its slightly lower accuracy, the power function is, at this stage, a more trustworthy model to characterize size-number distributions of seeds in soil banks because in some Weibull equations the estimates of the scale parameter were not acceptable.

关键词： accuracy power function seeds shape seeds size size-number distributions Weibull model.

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Plastic ingestion and associated additives in Faroe Islands chicks of the Northern Fulmar Fulmarus glacialis

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Water Biology and Security 2022年第4期1卷 68-76页

作者： France Collard Simon Leconte Johannis Danielsen Claudia Halsband Dorte Herzke Mikael Harju Felix Tulatz Geir W.Gabrielsen Arnaud Tarroux Norwegian Polar Institute Fram Centre for Climate and the EnvironmentFram CentreN-9296TromsøNorway Norwegian Institute for Nature Research Fram Centre for Climate and the EnvironmentFram CentreN-9296TromsøNorway Faroe Marine Research Institute 100TorshavnFaroe Islands Akvaplan-niva Fram Centre for Climate and the EnvironmentFram CentreN-9296TromsøNorway The Norwegian Institute for Air Research Fram Centre for Climate and the EnvironmentN-9296TromsøNorway

Northern Fulmars(Fulmarus glacialis)are a pelagic seabird species distributed at northern and polar *** are often used as an indicator of plastic pollution in the North Sea region,but data are lacking from higher latitudes,especially when it comes to ***,we investigated amounts of ingested plastic and their characteristics in fulmar chicks from the Faroe *** particles(≥1 mm)in chicks of two age classes were searched using a digestion method with *** addition,to evaluate if additive tissue burden reflects plastic ingestion,we measured liver tissue concentrations of two pollutant classes associated with plastic materials:polybrominated diphenyl ethers(PBDEs)and several dechloranes,using gas chromatography with high-resolution mass *** most common shape was hard fragment(81%)and the most common polymer was polyethylene(73%).Plastic contamination did not differ between either age class,and we found no correlation between neither the amount and mass of plastic particles and the concentration of *** comparison with previous studies on adult fulmars,we do not recommend using chicks for biomonitoring adults because chicks seem to ingest more plastics than adults.

关键词： Plastic pollution PBDE Dechlorane Arctic Early life stage Monitoring Seabird

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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

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Monthly soil erosion monitoring based on remotely sensed biophysical parameters: a case study in Strymonas river basin towards a functional pan-European service

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International Journal of Digital Earth 2012年第6期5卷 461-487页

作者： Panos Panagos Christos G.Karydas Ioannis ZGitas Luca Montanarella Joint Research centre of the European Commission Institute for Environment and SustainabilityIspraItaly School of Forestry and Natural environment Laboratory of Forest Management and Remote SensingAristotle University of ThessalonikiThessalonikiGreece

Currently,many soil erosion studies at local,regional,national or continental scale use models based on the USLE-family *** of these models pay little attention to seasonal changes,despite evidence in the literature which suggests that erosion risk may change rapidly according to intra-annual rainfall figures and vegetation *** paper emphasises the aspect of seasonality in soil erosion mapping by using month-step rainfall erosivity data and biophysical time series data derived from *** latter,together with other existing pan-European geo-databases sets the basis for a functional pan-European service for soil erosion monitoring at a scale of 1:500,*** potential service has led to the establishment of a new modelling approach(called the G2 model)based on the inheritance of USLE-family *** G2 model proposes innovative techniques for the estimation of vegetation and protection *** model has been applied in a 14,500 km 2 study area in SE Europe covering a major part of the basin of the cross-border river,*** results were verified with erosion and sedimentation figures from previous *** study confirmed that monthly erosion mapping would identify the critical months and would allow erosion figures to be linked to specific land uses.

关键词： soil erosion biophysical parameters digital earth European geo-databases Strymonas/Struma Sobel filter

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Speciation of organic phosphorus in a sediment profile of Lake Taihu I:Chemical forms and their transformation

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Journal of environmental Sciences 2013年第4期25卷 637-644页

作者： Di Xu Shiming Ding Bin Li Xiuling Bai Chengxin Fan Chaosheng Zhang State Key Laboratory of Lake Science and environment Nanjing Institute of Geography and LimnologyChinese Academy of Sciences College of Forest Resources and environment Nanjing Forestry University College of environment and Planning Henan University GIS centre Ryan Institute and School of Geography and ArchaeologyNational University of IrelandGalwayIreland

Organic phosphorus （nonreactive E NRP） is a major component of P in sediments, but information about its chemical forms and dynamic transformation is limited. The chemical forms and dynamic behaviors of NRP in a sediment profile from Lake Talhu, a freshwater and eutrophic lake in China, were investigated. Five forms of NRP in the sediments were extracted based on a chemical fractionation technique, including easily labile NRP （NaHCO3-NRP）, reactive metal oxide-bound NRP （HCl-NRP）, humic acid-associated NRP （NaOH-NRPnA）, fulvic acid-associated NRP （NaOH-NRPFA） and residual NRP （Res-TP）. There were notable transformations with increasing sediment depth from the labile NaHCOa-NRP and NaOH-NRP pools to the recalcitrant HCl-NRP and Res-TP pools, which caused the NRP to become increasingly recalcitrant as the early diagenetic processes proceeded. Further analyses showed that the relative changes in contents of organic matter and reactive Fe oxides in the sediment profile triggered a competition for binding NRP fractions and led to the transformation of NRP. The results highlighted the importance of abiotic processes in regulating the diagenesis of organic P and its stability in sediments.

关键词： organic phosphorus fractionation transformation Lake Taihu sediment

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Defining 'science-based targets'

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National Science Review 2021年第7期8卷 17-20页

作者： Inger Andersen Naoko Ishii Thomas Brooks Cynthia Cummis Gustavo Fonseca Astrid Hillers Nicholas Macfarlane Nebojsa Nakicenovic Kevin Moss Johan Rockstr?m rew Steer Dominic Waughray Caroline Zimm United Nations environment Programme Global environment Facility International Union for Conservation of Nature World Resources Institute International Institute for Applied Systems Analysis Potsdam Institute for Climate Impact Research Conservation International Stockholm Resilience centre World Economic Forum centre for Global Public Goods

The 2015 Paris Agreement to keep global warming well below 2?C above pre-industrial levels and aim towards limiting warming to 1.5?C marked a watershed in planetary governance, for two reasons. First, of course, it se...

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Fate and risk assessment of emerging contaminants in reclaimed water production processes

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Frontiers of environmental Science & Engineering 2021年第5期15卷 295-310页

作者： Yuan Meng Weiyi Liu Heidelore Fiedler Jinlan Zhang Xinrui Wei Xiaohui Liu Meng Peng Tingting Zhang Department of environmental Science and Engineering Research Centre for Resource and EnvironmentBeijing University of Chemical TechnologyBeijing100029China MTM Research centre School of Science and TechnologyOrebro UniversityOrebroSE-70182Sweden State Key Laboratory of environmental Criteria and Risk Assessment National Engineering Laboratory for Lake Pollution Control and Ecological RestorationResearch Centre of Lake EnvironmentChinese Research Academy of Environmental SciencesBeijing100012China School of environment Tsinghua UniversityBeijing100084China

Reclaimed water has been widely applied in irrigation and industrial *** the behavior of emerging contaminants in the production process of reclaimed water is the first prerequisite for developing relevant water quality *** study investigated 43 emerging contaminants,including 22 pharmaceuticals and personal care products(PPCPs),11 organophosphorus flame retardants(OPFRs),and 10 antibiotic resistance genes(ARGs)in 3 reclaimed wastewater treatment plants(RWTPs)in *** composition profiles and removal efficiencies of these contaminants in RWTPs were *** results indicated that the distribution characteristics of the different types of contaminants in the three RWTPs were ***,sul2 and tris(1-chloro-2-propyl)phosphate were the dominant substances in the wastewater,and their highest concentrations were 27104 ng/L,1.4×10^(7) copies/mL and 262 ng/L,*** and sul2 were observed to be the dominant substances in the sludge,and their highest concentrations were 5419 ng/g and 3.7×10^(8) copies/g,***/anoxic/oxic system combined with the membrane bioreactor process achieved a relatively high aqueous removal of PPCPs(87%).ARGs and OPFRs were challenging to remove,with average removal rates of 6.5%and 31%,*** meta-analysis indicated that tertiary treatment processes performed better in emerging contaminant removal than secondary *** exhibited the highest mass load discharge,with 33.5 mg/d per 1000 *** and tris(2-ethylhexyl)phosphate posed high risks(risk quotient>1.0)to aquatic *** study provides essential evidence to screen high priority pollutants and develop corresponding standard in RWTPs.

关键词： Trace organic pollution Antibiotic resistance genes Reclaimed wastewater Sludge Risk assessment Mass load

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