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  1 / 12084 MEDLINE  
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[PMID]:29478650
[Au] Autor:Dong W; Guo J; Xu L; Song Z; Zhang J; Tang A; Zhang X; Leng C; Liu Y; Wang L; Wang L; Yu Y; Yang Z; Yu Y; Meng Y; Lai Y
[Ad] Endereço:Heilongjiang Academy of Agricultural Sciences Postdoctoral Programme, Harbin 150086, China; Cultivation and Farming Research Institute, Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China; Northern Japonica Rice Molecular Breeding Joint Research Center, Chinese Academy of Sciences, H
[Ti] Título:Water regime-nitrogen fertilizer incorporation interaction: Field study on methane and nitrous oxide emissions from a rice agroecosystem in Harbin, China.
[So] Source:J Environ Sci (China);64:289-297, 2018 Feb.
[Is] ISSN:1001-0742
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Water regime and nitrogen (N) fertilizer are two important factors impacting greenhouse gases (GHG) emission from paddy field, whereas their effects have not been well studied in cold region. In this study, we conducted a two-year field experiment to study the impacts of water regime and N fertilizer on rice yields and GHG emissions in Harbin, China, a cold region located in high latitudes. Our results showed that intermittent irrigation significantly decreased methane (CH ) emission compared with continuous flooding, however, the decrement was far lower than the global average level. The N O emissions were very small when flooded but peaked at the beginning of the disappearance of floodwater. The N fertilizer treatments increased CH emissions at low level (75kgN/ha). But both CH and N O emissions were uninfluenced at the levels of 150kgN/ha and 225kgN/ha. Rice yields increased under intermittent irrigation and were highest at the level of 150kgN/ha. From our results, we recommended that the intermittent irrigation and 150kgN/ha as the ideal water regime-nitrogen fertilizer incorporation for this area to achieve low GHG emissions without impacting rice yields.
[Mh] Termos MeSH primário: Agricultura
Poluentes Atmosféricos/análise
Ecossistema
Fertilizantes/análise
Água Doce/química
Óxido Nitroso/análise
[Mh] Termos MeSH secundário: Poluentes Atmosféricos/química
China
Ciclo do Nitrogênio
Óxido Nitroso/química
Oryza
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Air Pollutants); 0 (Fertilizers); K50XQU1029 (Nitrous Oxide)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180301
[Lr] Data última revisão:
180301
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180227
[St] Status:MEDLINE


  2 / 12084 MEDLINE  
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[PMID]:29315308
[Au] Autor:Duffee L; Columbano N; Scanu A; Melosu V; Careddu GM; Sotgiu G; Driessen B
[Ad] Endereço:Department of Clinical Studies-New Bolton Center, University of Pennsylvania, School of Veterinary Medicine, Kennett Square, Pennsylvania, United States of America.
[Ti] Título:MAC-sparing effect of nitrous oxide in sevoflurane anesthetized sheep and its reversal with systemic atipamezole administration.
[So] Source:PLoS One;13(1):e0190167, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:INTRODUCTION: Nitrous oxide (N2O) is an anesthetic gas with antinociceptive properties and reduces the minimum alveolar concentration (MAC) for volatile anesthetic agents, potentially through mechanisms involving central alpha2-adrenoceptors. We hypothesized that 70% N2O in the inspired gas will significantly reduce the MAC of sevoflurane (MACSEVO) in sheep, and that this effect can be reversed by systemic atipamezole. MATERIALS AND METHODS: Animals were initially anesthetized with SEVO in oxygen (O2) and exposed to an electrical current as supramaximal noxious stimulus in order to determine MACSEVO (in duplicates). Thereafter, 70% N2O was added to the inspired gas and the MAC re-determined in the presence of N2O (MACSN). A subgroup of sheep were anesthetized a second time with SEVO/N2O for re-determination of MACSN, after which atipamezole (0.2 mg kg-1, IV) was administered for MACSNA determinations. Sheep were anesthetized a third time, initially with only SEVO/O2 to re-determine MACSEVO, after which atipamezole (0.2 mg kg-1, IV) was administered for determination of MACSA. RESULTS: MACSEVO was 2.7 (0.3)% [mean (standard deviation)]. Addition of N2O resulted in a 37% reduction of MACSEVO to MACSN of 1.7 (0.2)% (p <0.0001). Atipamezole reversed this effect, producing a MACSNA of 3.1 (0.7)%, which did not differ from MACSEVO (p = 0.12). MACSEVO did not differ from MACSA (p = 0.69). Cardiorespiratory variables were not different among experimental groups except a lower ETCO2 in animals exposed to SEVO/N2O. CONCLUSIONS: N2O produces significant MACSEVO-reduction in sheep; this effect is completely reversed by IV atipamezole confirming the involvement of alpha2-adrenoreceptors in the MAC-sparing action of N2O.
[Mh] Termos MeSH primário: Anestésicos Inalatórios/administração & dosagem
Imidazóis/administração & dosagem
Éteres Metílicos/administração & dosagem
Óxido Nitroso/efeitos adversos
[Mh] Termos MeSH secundário: Animais
Ovinos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anesthetics, Inhalation); 0 (Imidazoles); 0 (Methyl Ethers); 03N9U5JAF6 (atipamezole); 38LVP0K73A (sevoflurane); K50XQU1029 (Nitrous Oxide)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180129
[Lr] Data última revisão:
180129
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180110
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0190167


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[PMID]:29253001
[Au] Autor:Xu K; Wang C; Yang X
[Ad] Endereço:College of Environmental Science and Engineering, Beijing Forestry University, Beijing, China.
[Ti] Título:Five-year study of the effects of simulated nitrogen deposition levels and forms on soil nitrous oxide emissions from a temperate forest in northern China.
[So] Source:PLoS One;12(12):e0189831, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Few studies have quantified the effects of different levels and forms of nitrogen (N) deposition on soil nitrous oxide (N2O) emissions from temperate forest soils. A 5-year field experiment was conducted to investigate the effects of multiple forms and levels of N additions on soil N2O emissions, by using the static closed chamber method at Xi Mountain Experimental Forest Station in northern China. The experiment included a control (no N added), and additions of NH4NO3, NaNO3, and (NH4)2SO4 that each had two levels: 50 kg N ha-1 yr-1 and 150 kg N ha-1 yr-1. All plots were treated to simulate increased N deposition on a monthly schedule during the annual growing season (March to October) and soil N2O emissions were measured monthly from March 2011 to February 2016. Simultaneously, the temperature, moisture, and inorganic N contents of soil were also measured to explore how the main factors may have affected soil N2O emission. The results showed that the types and levels of N addition significantly increased soil inorganic N contents, and the accumulation of soil NO3--N was significantly higher than that of soil NH4+-N due to N addition. The three N forms significantly increased the average N2O emissions (P < 0.05) in the order of NH4NO3 > (NH4)2SO4 > NaNO3 by 355.95%, 266.35%, and 187.71%, respectively, compared with control. The promotion of N2O emission via the NH4+-N addition was significantly more than that via the NO3--N addition, while N addition at a high level exerted a stronger effect than at the low-level. N addition exerted significantly stronger effects on cumulative N2O emissions in the initial years, especially the third year when the increased cumulative N2O emission reached their maximum. In the later years, the increases persisted but were weakened. Increasing inorganic N concentration could change soil from being N-limited to N-rich, and then N-saturated, and so the promotion on soil available N effect increased and then decreased. Moreover, the soil NH4+-N, NO3--N, temperature, and water-filled pore space were all positively correlated with soil N2O emissions. These findings suggest that atmospheric N deposition can significantly promote soil N2O emission, and that exogenous NH4+-N and NO3--N inputs into temperate forests can have synergic effects on soil N2O emission. In future research, both aspects should be better distinguished in the N cycle and balance of terrestrial ecosystems by using 15N tracer methods.
[Mh] Termos MeSH primário: Florestas
Nitrogênio/química
Óxido Nitroso/química
Solo/química
[Mh] Termos MeSH secundário: China
Monitoramento Ambiental
Gases
Seres Humanos
Estações do Ano
Temperatura Ambiente
Água
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Gases); 0 (Soil); 059QF0KO0R (Water); K50XQU1029 (Nitrous Oxide); N762921K75 (Nitrogen)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180112
[Lr] Data última revisão:
180112
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171219
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0189831


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[PMID]:28467840
[Au] Autor:Frutos OD; Cortes I; Cantera S; Arnaiz E; Lebrero R; Muñoz R
[Ad] Endereço:Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina , s/n, 47011, Valladolid, Spain.
[Ti] Título:Nitrous Oxide Abatement Coupled with Biopolymer Production As a Model GHG Biorefinery for Cost-Effective Climate Change Mitigation.
[So] Source:Environ Sci Technol;51(11):6319-6325, 2017 Jun 06.
[Is] ISSN:1520-5851
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:N O represents ∼6% of the global greenhouse gas emission inventory and the most important O -depleting substance emitted in this 21st century. Despite its environmental relevance, little attention has been given to cost-effective and environmentally friendly N O abatement methods. Here we examined, the potential of a bubble column (BCR) and an internal loop airlift (ALR) bioreactors of 2.3 L for the abatement of N O from a nitric acid plant emission. The process was based on the biological reduction of N O by Paracoccus denitrificans using methanol as a carbon/electron source. Two nitrogen limiting strategies were also tested for the coproduction of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) coupled with N O reduction. High N O removal efficiencies (REs) (≈87%) together with a low PHBV cell accumulation were observed in both bioreactors in excess of nitrogen. However, PHBV contents of 38-64% were recorded under N limiting conditions along with N O-REs of ≈57% and ≈84% in the ALR and BCR, respectively. Fluorescence in situ hybridization analyses showed that P. denitrificans was dominant (>50%) after 6 months of experimentation. The successful abatement of N O concomitant with PHBV accumulation confirmed the potential of integrating biorefinery concepts into biological gas treatment for a cost-effective GHG mitigation.
[Mh] Termos MeSH primário: Biopolímeros
Mudança Climática
Óxido Nitroso
[Mh] Termos MeSH secundário: Reatores Biológicos
Hibridização in Situ Fluorescente
Ácidos Pentanoicos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biopolymers); 0 (Pentanoic Acids); 10237-77-1 (beta-hydroxyvaleric acid); K50XQU1029 (Nitrous Oxide)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171215
[Lr] Data última revisão:
171215
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE
[do] DOI:10.1021/acs.est.7b00643


  5 / 12084 MEDLINE  
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[PMID]:28467048
[Au] Autor:Enanga EM; Casson NJ; Fairweather TA; Creed IF
[Ad] Endereço:Department of Biology, Western University , 1151 Richmond Street, London, Ontario Canada , N6A 5B7.
[Ti] Título:Nitrous Oxide and Dinitrogen: The Missing Flux in Nitrogen Budgets of Forested Catchments?
[So] Source:Environ Sci Technol;51(11):6036-6043, 2017 Jun 06.
[Is] ISSN:1520-5851
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Most forest nitrogen budgets are imbalanced, with nitrogen inputs exceeding nitrogen outputs. The denitrification products nitrous oxide (N O) and dinitrogen (N ) represent often-unmeasured fluxes that may close the gap between explained nitrogen inputs and outputs. Gaseous N O and N effluxes, dissolved N O flux, and traditionally measured dissolved nitrogen species (i.e., nitrate, ammonium, and dissolved organic nitrogen) were estimated to account for the annual nitrogen output along hillslope gradients from two catchments in a temperate forest. Adding N O and N effluxes to catchment nitrogen output not only reduced the discrepancy between nitrogen inputs and outputs (9.9 kg ha yr and 6.5 or 6.3 kg ha yr , respectively), but also between nitrogen outputs from two catchments with different topographies (6.5 kg ha yr for the catchment with a large wetland, 6.3 kg ha yr for the catchment with a very small wetland). Dissolved N O comprised a very small portion of the annual nitrogen outputs. Nitrogen inputs exceeded nitrogen outputs throughout the year except during spring runoff, and also during autumn storms in the catchment with the large wetland. Failing to account for denitrification products, especially during summer rainfall events, may lead to underestimation of annual nitrogen losses.
[Mh] Termos MeSH primário: Florestas
Nitrogênio
Óxido Nitroso
[Mh] Termos MeSH secundário: Desnitrificação
Zonas Úmidas
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
K50XQU1029 (Nitrous Oxide); N762921K75 (Nitrogen)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171211
[Lr] Data última revisão:
171211
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE
[do] DOI:10.1021/acs.est.6b03728


  6 / 12084 MEDLINE  
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[PMID]:28745779
[Au] Autor:Dämmgen U; Brade W; Haenel HD; Rösemann C; Dämmgen J; Meyer U
[Ad] Endereço:Ulrich Dämmgen, Weststraße 5, 38162 Weddel, E-Mail: ulrich.daemmgen@daemmgen.de.
[Ti] Título:[Emissions from dairy industry and the influence of herd management].
[Ti] Título:Emissionen aus der Milchrinderhaltung und ihre Beeinflussung durch das Herdenmanagement..
[So] Source:Tierarztl Prax Ausg G Grosstiere Nutztiere;45(4):226-236, 2017 Aug 11.
[Is] ISSN:1434-1220
[Cp] País de publicação:Germany
[La] Idioma:ger
[Ab] Resumo:The purpose of this paper is to identify specific emission-reduction opportunities in dairy herds arising from aspects of useful herd management with the potential to reduce emissions, which are within the scope of veterinary activities. In future, it might be one of a veterinarian's advisory capacities to deal with the aspect of climate and environmental protection in animal husbandry. The models involved are similar to those of the national agricultural emission inventory. They allow quantifying the impacts of improved animal health, extended productive lifespan and grazing of an entire dairy herd (cows, calves, heifers and bulls) on emissions from the herd itself, in addition to those originating from the entire production chain, including provision of primary energy, water, feed production and processing. Ammonia emissions are the main focus. The reductions achieved here are not huge, though noticeable. They do not create extra costs. As can be shown, improved animal health and welfare are also environmentally beneficial. The reduction of greenhouse gas and air pollutant (eutrophying and acidifying gases and particles) emissions is an acknowledged political goal. If Germany wants to achieve the emission ceilings it has agreed to, agriculture will have to contribute. Planning will have to precede action if agriculture is itself to keep control of the processes.
[Mh] Termos MeSH primário: Criação de Animais Domésticos
Indústria de Laticínios/métodos
Metano/biossíntese
[Mh] Termos MeSH secundário: Criação de Animais Domésticos/métodos
Animais
Animais Recém-Nascidos
Bovinos
Indústria de Laticínios/estatística & dados numéricos
Feminino
Alemanha
Efeito Estufa
Masculino
Metano/efeitos adversos
Leite
Óxido Nitroso/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
K50XQU1029 (Nitrous Oxide); OP0UW79H66 (Methane)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171201
[Lr] Data última revisão:
171201
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170727
[St] Status:MEDLINE
[do] DOI:10.15653/TPG-161164


  7 / 12084 MEDLINE  
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[PMID]:28470424
[Au] Autor:Hong X; Chen Z; Zhao C; Yang S
[Ad] Endereço:Department of Bioengineering and Biotechnology, Huaqiao University, No. 668 Jimei Ave, Xiamen, 361021, People's Republic of China.
[Ti] Título:Nitrogen transformation under different dissolved oxygen levels by the anoxygenic phototrophic bacterium Marichromatium gracile.
[So] Source:World J Microbiol Biotechnol;33(6):113, 2017 Jun.
[Is] ISSN:1573-0972
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Marichromatium gracile: YL28 (M. gracile YL28) is an anoxygenic phototrophic bacterial strain that utilizes ammonia, nitrate, or nitrite as its sole nitrogen source during growth. In this study, we investigated the removal and transformation of ammonium, nitrate, and nitrite by M. gracile YL28 grown in a combinatorial culture system of sodium acetate-ammonium, sodium acetate-nitrate and sodium acetate-nitrite in response to different initial dissolved oxygen (DO) levels. In the sodium acetate-ammonium system under aerobic conditions (initial DO = 7.20-7.25 mg/L), we detected a continuous accumulation of nitrate and nitrite. However, under semi-anaerobic conditions (initial DO = 4.08-4.26 mg/L), we observed a temporary accumulation of nitrate and nitrite. Interestingly, under anaerobic conditions (initial DO = 0.36-0.67 mg/L), there was little accumulation of nitrate and nitrite, but an increase in nitrous oxide production. In the sodium acetate-nitrite system, nitrite levels declined slightly under aerobic conditions, and nitrite was completely removed under semi-anaerobic and anaerobic conditions. In addition, M. gracile YL28 was able to grow using nitrite as the sole nitrogen source in situations when nitrogen gas produced by denitrification was eliminated. Taken together, the data indicate that M. gracile YL28 performs simultaneous heterotrophic nitrification and denitrification at low-DO levels and uses nitrite as the sole nitrogen source for growth. Our study is the first to demonstrate that anoxygenic phototrophic bacteria perform heterotrophic ammonia-oxidization and denitrification under anaerobic conditions.
[Mh] Termos MeSH primário: Anaerobiose/fisiologia
Chromatiaceae/metabolismo
Nitrogênio/metabolismo
Oxigênio/metabolismo
Processos Fototróficos/fisiologia
[Mh] Termos MeSH secundário: Acetatos/metabolismo
Aerobiose/fisiologia
Amônia/metabolismo
Compostos de Amônio/metabolismo
Bactérias
Chromatiaceae/crescimento & desenvolvimento
Desnitrificação
Processos Heterotróficos/fisiologia
Cinética
Nitratos/metabolismo
Nitrificação
Nitritos/metabolismo
Óxido Nitroso/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetates); 0 (Ammonium Compounds); 0 (Nitrates); 0 (Nitrites); 7664-41-7 (Ammonia); K50XQU1029 (Nitrous Oxide); N762921K75 (Nitrogen); RRE756S6Q2 (ammonium acetate); S88TT14065 (Oxygen)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171201
[Lr] Data última revisão:
171201
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170505
[St] Status:MEDLINE
[do] DOI:10.1007/s11274-017-2280-z


  8 / 12084 MEDLINE  
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[PMID]:28830043
[Au] Autor:Sun S; Bao Z; Li R; Sun D; Geng H; Huang X; Lin J; Zhang P; Ma R; Fang L; Zhang X; Zhao X
[Ad] Endereço:College of Chemistry and Enviromental Engineering, Shenzhen University, Shenzhen 518060, China; College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China.
[Ti] Título:Reduction and prediction of N O emission from an Anoxic/Oxic wastewater treatment plant upon DO control and model simulation.
[So] Source:Bioresour Technol;244(Pt 1):800-809, 2017 Nov.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In order to make a better understanding of the characteristics of N O emission in A/O wastewater treatment plant, full-scale and pilot-scale experiments were carried out and a back propagation artificial neural network model based on the experimental data was constructed to make a precise prediction of N O emission. Results showed that, N O flux from different units followed a descending order: aerated grit tank>oxic zone≫anoxic zone>final clarifier>primary clarifier, but 99.4% of the total emission of N O (1.60% of N-load) was monitored from the oxic zone due to its big surface area. A proper DO control could reduce N O emission down to 0.21% of N-load in A/O process, and a two-hidden-layers back propagation model with an optimized structure of 4:3:9:1 could achieve a good simulation of N O emission, which provided a new method for the prediction of N O emission during wastewater treatment.
[Mh] Termos MeSH primário: Águas Residuais
[Mh] Termos MeSH secundário: Reatores Biológicos
Óxido Nitroso
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Waste Water); K50XQU1029 (Nitrous Oxide)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171023
[Lr] Data última revisão:
171023
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170823
[St] Status:MEDLINE


  9 / 12084 MEDLINE  
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[PMID]:28818711
[Au] Autor:Mannina G; Capodici M; Cosenza A; Laudicina VA; Di Trapani D
[Ad] Endereço:Dipartimento di Ingegneria Civile, Ambientale, Aerospaziale, dei Materiali, Università di Palermo, Viale delle Scienze, Ed. 8, 90128, Palermo, Italy.
[Ti] Título:The influence of solid retention time on IFAS-MBR systems: Assessment of nitrous oxide emission.
[So] Source:J Environ Manage;203(Pt 1):391-399, 2017 Dec 01.
[Is] ISSN:1095-8630
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The aim of the present study was to investigate the nitrous oxide (N O) emissions from a moving bed based Integrated Fixed Film Activated Sludge (IFAS) - membrane bioreactor (MBR) pilot plant, designed according to the University of Cape Town (UCT) layout. The experimental campaign had a duration of 110 days and was characterized by three different sludge retention time (SRT) values (∞, 30 d and 15 d). Results highlighted that N O concentrations decreased when the biofilm concentrations increased within the aerobic reactor. Results have shown an increase of N O with the decrease of SRT. Specifically, an increase of N O-N emission factor occurred with the decrease of the SRT (0.13%, 0.21% and 0.76% of influent nitrogen for SRT = ∞, SRT = 30 d and SRT = 15 d, respectively). Moreover, the MBR tank resulted the key emission source (up to 70% of the total N O emission during SRT = ∞ period) whereas the highest N O production occurred in the anoxic reactor. Moreover, N O concentrations measured in the permeate flow were not negligible, thus highlighting its potential detrimental contribution for the receiving water body. The role of each plant reactor as N O-N producer/consumer varies with the SRT variation, indeed the aerobic reactor was a N O consumer at SRT = ∞ and a producer at SRT = 30 d.
[Mh] Termos MeSH primário: Reatores Biológicos
Óxido Nitroso
[Mh] Termos MeSH secundário: Biofilmes
Nitrogênio
Esgotos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Sewage); K50XQU1029 (Nitrous Oxide); N762921K75 (Nitrogen)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171113
[Lr] Data última revisão:
171113
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170819
[St] Status:MEDLINE


  10 / 12084 MEDLINE  
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[PMID]:28780360
[Au] Autor:Kinh CT; Suenaga T; Hori T; Riya S; Hosomi M; Smets BF; Terada A
[Ad] Endereço:Department of Chemical Engineering, Tokyo University of Agriculture and Technology, Naka 2-24-16, Koganei, Tokyo, 184-8588, Japan.
[Ti] Título:Counter-diffusion biofilms have lower N O emissions than co-diffusion biofilms during simultaneous nitrification and denitrification: Insights from depth-profile analysis.
[So] Source:Water Res;124:363-371, 2017 Nov 01.
[Is] ISSN:1879-2448
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The goal of this study was to investigate the effectiveness of a membrane-aerated biofilm reactor (MABR), a representative of counter-current substrate diffusion geometry, in mitigating nitrous oxide (N O) emission. Two laboratory-scale reactors with the same dimensions but distinct biofilm geometries, i.e., a MABR and a conventional biofilm reactor (CBR) employing co-current substrate diffusion geometry, were operated to determine depth profiles of dissolved oxygen (DO), nitrous oxide (N O), functional gene abundance and microbial community structure. Surficial nitrogen removal rate was slightly higher in the MABR (11.0 ± 0.80 g-N/(m day) than in the CBR (9.71 ± 0.94 g-N/(m day), while total organic carbon removal efficiencies were comparable (96.9 ± 1.0% for MABR and 98.0 ± 0.8% for CBR). In stark contrast, the dissolved N O concentration in the MABR was two orders of magnitude lower (0.011 ± 0.001 mg N O-N/L) than that in the CBR (1.38 ± 0.25 mg N O-N/L), resulting in distinct N O emission factors (0.0058 ± 0.0005% in the MABR vs. 0.72 ± 0.13% in the CBR). Analysis on local net N O production and consumption rates unveiled that zones for N O production and consumption were adjacent in the MABR biofilm. Real-time quantitative PCR indicated higher abundance of denitrifying genes, especially nitrous oxide reductase (nosZ) genes, in the MABR versus the CBR. Analyses of the microbial community composition via 16S rRNA gene amplicon sequencing revealed the abundant presence of the genera Thauera (31.2 ± 11%), Rhizobium (10.9 ± 6.6%), Stenotrophomonas (6.8 ± 2.7%), Sphingobacteria (3.2 ± 1.1%) and Brevundimonas (2.5 ± 1.0%) as potential N O-reducing bacteria in the MABR.
[Mh] Termos MeSH primário: Biofilmes
Reatores Biológicos
Desnitrificação
[Mh] Termos MeSH secundário: Bactérias/genética
Bactérias/metabolismo
Nitrificação
Óxido Nitroso
RNA Ribossômico 16S
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Ribosomal, 16S); K50XQU1029 (Nitrous Oxide)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171018
[Lr] Data última revisão:
171018
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170807
[St] Status:MEDLINE



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