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  1. Article ; Online: Emulsion-based recovery of a multicomponent petroleum hydrocarbon NAPL using nonionic surfactant formulations.

    Ramsburg, C Andrew / Baniahmad, Parnian / Muller, Katherine A / Robinson, Andrew D

    Journal of contaminant hydrology

    2023  Volume 255, Page(s) 104144

    Abstract: Surfactants can aid subsurface remediation through three primary mechanisms - solubilization, mobilization and/or emulsification. Among these mechanisms, emulsification in porous media is generally not well studied or well understood; particularly in the ...

    Abstract Surfactants can aid subsurface remediation through three primary mechanisms - solubilization, mobilization and/or emulsification. Among these mechanisms, emulsification in porous media is generally not well studied or well understood; particularly in the context of treating sources containing multicomponent NAPL. The objective of this research was to elucidate the processes responsible for recovery of a multicomponent hydrocarbon NAPL when surfactant solutions are introduced within a porous medium to promote the formation of kinetically-stable oil-in-water emulsions. Emulsifier formulations considered here were selected to offer similar performance characteristics while relying on different families of non-ionic surfactants - nonylphenol ethoxylates or alcohol ethoxylates - for emulsification. The families of surfactants have particular environment relevance, as alcohol ethoxylates are often used where replacement of nonylphenol content is necessary. Results from batch and column studies suggest performance of the two formulations was similar. With both, a synergistic combination of emulsification and mobilization led to recovery of a synthetic gasoline NAPL. The relative contribution of solubilization to the recovery was found to be minor. Moreover, the physical processes associated with emulsification and mobilization acted to limit the amount of preferential recovery (or fractionation) of the multicomponent NAPL.
    MeSH term(s) Petroleum ; Emulsions ; Surface-Active Agents ; Hydrocarbons ; Ethanol
    Chemical Substances Petroleum ; nonylphenol (79F6A2ILP5) ; Emulsions ; Surface-Active Agents ; Hydrocarbons ; Ethanol (3K9958V90M)
    Language English
    Publishing date 2023-02-04
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 1494766-3
    ISSN 1873-6009 ; 0169-7722
    ISSN (online) 1873-6009
    ISSN 0169-7722
    DOI 10.1016/j.jconhyd.2023.104144
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Emulsion-based recovery of a multicomponent petroleum hydrocarbon NAPL using nonionic surfactant formulations

    Ramsburg, C. Andrew / Baniahmad, Parnian / Muller, Katherine A. / Robinson, Andrew D.

    Journal of Contaminant Hydrology. 2023 Feb. 04, p.104144-

    2023  , Page(s) 104144–

    Abstract: Surfactants can aid subsurface remediation through three primary mechanisms - solubilization, mobilization and/or emulsification. Among these mechanisms, emulsification in porous media is generally not well studied or well understood; particularly in the ...

    Abstract Surfactants can aid subsurface remediation through three primary mechanisms - solubilization, mobilization and/or emulsification. Among these mechanisms, emulsification in porous media is generally not well studied or well understood; particularly in the context of treating sources containing multicomponent NAPL. The objective of this research was to elucidate the processes responsible for recovery of a multicomponent hydrocarbon NAPL when surfactant solutions are introduced within a porous medium to promote the formation of kinetically-stable oil-in-water emulsions. Emulsifier formulations considered here were selected to offer similar performance characteristics while relying on different families of non-ionic surfactants - nonylphenol ethoxylates or alcohol ethoxylates - for emulsification. The families of surfactants have particular environment relevance, as alcohol ethoxylates are often used where replacement of nonylphenol content is necessary. Results from batch and column studies suggest performance of the two formulations was similar. With both, a synergistic combination of emulsification and mobilization led to recovery of a synthetic gasoline NAPL. The relative contribution of solubilization to the recovery was found to be minor. Moreover, the physical processes associated with emulsification and mobilization acted to limit the amount of preferential recovery (or fractionation) of the multicomponent NAPL.
    Keywords emulsifiers ; emulsifying ; fractionation ; gasoline ; hydrology ; nonionic surfactants ; nonylphenols ; petroleum ; porous media ; remediation ; solubilization ; Diesel ; Petroleum hydrocarbon ; TPH ; EPH ; GRO ; DRO ; Surfactant ; SEAR ; Source zone
    Language English
    Dates of publication 2023-0204
    Publishing place Elsevier B.V.
    Document type Article ; Online
    Note Pre-press version
    ZDB-ID 1494766-3
    ISSN 1873-6009 ; 0169-7722
    ISSN (online) 1873-6009
    ISSN 0169-7722
    DOI 10.1016/j.jconhyd.2023.104144
    Database NAL-Catalogue (AGRICOLA)

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  3. Article ; Online: Atmospheric isoprene measurements reveal larger-than-expected Southern Ocean emissions.

    Ferracci, Valerio / Weber, James / Bolas, Conor G / Robinson, Andrew D / Tummon, Fiona / Rodríguez-Ros, Pablo / Cortés-Greus, Pau / Baccarini, Andrea / Jones, Roderic L / Galí, Martí / Simó, Rafel / Schmale, Julia / Harris, Neil R P

    Nature communications

    2024  Volume 15, Issue 1, Page(s) 2571

    Abstract: Isoprene is a key trace component of the atmosphere emitted by vegetation and other organisms. It is highly reactive and can impact atmospheric composition and climate by affecting the greenhouse gases ozone and methane and secondary organic aerosol ... ...

    Abstract Isoprene is a key trace component of the atmosphere emitted by vegetation and other organisms. It is highly reactive and can impact atmospheric composition and climate by affecting the greenhouse gases ozone and methane and secondary organic aerosol formation. Marine fluxes are poorly constrained due to the paucity of long-term measurements; this in turn limits our understanding of isoprene cycling in the ocean. Here we present the analysis of isoprene concentrations in the atmosphere measured across the Southern Ocean over 4 months in the summertime. Some of the highest concentrations ( >500 ppt) originated from the marginal ice zone in the Ross and Amundsen seas, indicating the marginal ice zone is a significant source of isoprene at high latitudes. Using the United Kingdom Earth System Model we show that current estimates of sea-to-air isoprene fluxes underestimate observed isoprene by a factor >20. A daytime source of isoprene is required to reconcile models with observations. The model presented here suggests such an increase in isoprene emissions would lead to >8% decrease in the hydroxyl radical in regions of the Southern Ocean, with implications for our understanding of atmospheric oxidation and composition in remote environments, often used as proxies for the pre-industrial atmosphere.
    Language English
    Publishing date 2024-03-22
    Publishing country England
    Document type Journal Article
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-024-46744-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Seasonal and long term variations of surface ozone concentrations in Malaysian Borneo

    Mohd. Talib Latif / Dominick, Doreena / Ahamad, Fatimah / Ahamad, Nur Shuhada / Khan, Md Firoz / Juneng, Liew / Xiang, Chung Jing / Nadzir, Mohd Shahrul Mohd / Robinson, Andrew D. / Ismail Marzuki / Mead, Mohammed Iqbal / Harris, Neil R.P.

    Science of the total environment. 2016 Dec. 15, v. 573 p.494-504

    2016  

    Abstract: Malaysian Borneo has a lower population density and is an area known for its lush rainforests. However, changes in pollutant profiles are expected due to increasing urbanisation and commercial-industrial activities. This study aims to determine the ... ...

    Abstract Malaysian Borneo has a lower population density and is an area known for its lush rainforests. However, changes in pollutant profiles are expected due to increasing urbanisation and commercial-industrial activities. This study aims to determine the variation of surface O₃ concentration recorded at seven selected stations in Malaysian Borneo. Hourly surface O₃ data covering the period 2002 to 2013, obtained from the Malaysian Department of Environment (DOE), were analysed using statistical methods. The results show that the concentrations of O₃ recorded in Malaysian Borneo during the study period were below the maximum Malaysian Air Quality Standard of 100ppbv. The hourly average and maximum O₃ concentrations of 31 and 92ppbv reported at Bintulu (S3) respectively were the highest among the O₃ concentrations recorded at the sampling stations. Further investigation on O₃ precursors show that sampling sites located near to local petrochemical industrial activities, such as Bintulu (S3) and Miri (S4), have higher NO₂/NO ratios (between 3.21 and 5.67) compared to other stations. The normalised O₃ values recorded at all stations were higher during the weekend compared to weekdays (unlike its precursors) which suggests the influence of O₃ titration by NO during weekdays. The results also show that there are distinct seasonal variations in O₃ across Borneo. High surface O₃ concentrations were usually observed between August and September at all stations with the exception of station S7 on the east coast. Majority of the stations (except S1 and S6) have recorded increasing averaged maximum concentrations of surface O₃ over the analysed years. Increasing trends of NO₂ and decreasing trends of NO influence the yearly averaged maximum of O₃ especially at S3. This study also shows that variations of meteorological factors such as wind speed and direction, humidity and temperature influence the concentration of surface O₃.
    Keywords air quality ; coasts ; humidity ; nitric oxide ; nitrogen dioxide ; ozone ; pollutants ; population density ; rain forests ; seasonal variation ; statistical analysis ; temperature ; titration ; urbanization ; wind speed ; Borneo ; Surface ozone ; Ozone precursors ; Meteorological factors ; Seasonal variations
    Language English
    Dates of publication 2016-1215
    Size p. 494-504.
    Publishing place Elsevier B.V.
    Document type Article ; Online
    ZDB-ID 121506-1
    ISSN 1879-1026 ; 0048-9697
    ISSN (online) 1879-1026
    ISSN 0048-9697
    DOI 10.1016/j.scitotenv.2016.08.121
    Database NAL-Catalogue (AGRICOLA)

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  5. Article ; Online: Seasonal and long term variations of surface ozone concentrations in Malaysian Borneo.

    Latif, Mohd Talib / Dominick, Doreena / Ahamad, Fatimah / Ahamad, Nur Shuhada / Khan, Md Firoz / Juneng, Liew / Xiang, Chung Jing / Nadzir, Mohd Shahrul Mohd / Robinson, Andrew D / Ismail, Marzuki / Mead, Mohammed Iqbal / Harris, Neil R P

    The Science of the total environment

    2016  Volume 573, Page(s) 494–504

    Abstract: Malaysian Borneo has a lower population density and is an area known for its lush rainforests. However, changes in pollutant profiles are expected due to increasing urbanisation and commercial-industrial activities. This study aims to determine the ... ...

    Abstract Malaysian Borneo has a lower population density and is an area known for its lush rainforests. However, changes in pollutant profiles are expected due to increasing urbanisation and commercial-industrial activities. This study aims to determine the variation of surface O
    Language English
    Publishing date 2016-12-15
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 121506-1
    ISSN 1879-1026 ; 0048-9697
    ISSN (online) 1879-1026
    ISSN 0048-9697
    DOI 10.1016/j.scitotenv.2016.08.121
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Book ; Online: Estimating the size of a methane emission point source at different scales

    Riddick, Stuart N. / Connors, Sarah / Robinson, Andrew D. / Manning, Alistair J. / Jones, Pippa S. D. / Lowry, David / Nisbet, Euan / Skelton, Robert L. / Allen, Grant / Pitt, Joseph / Harris, Neil R. P.

    eISSN: 1680-7324

    from local to landscape

    2017  

    Abstract: High methane (CH 4 ) mixing ratios (up to 4 ppm) have occurred sporadically at our measurement site in Haddenham, Cambridgeshire, since July 2012. Isotopic measurements and back trajectories show that the source is the Waterbeach Waste Management Park 7 ... ...

    Abstract High methane (CH 4 ) mixing ratios (up to 4 ppm) have occurred sporadically at our measurement site in Haddenham, Cambridgeshire, since July 2012. Isotopic measurements and back trajectories show that the source is the Waterbeach Waste Management Park 7 km SE of Haddenham. To investigate this further, measurements were made on 30 June and 1 July 2015 at other locations nearer to the source. Landfill emissions have been estimated using three different approaches at different scales; near source using the WindTrax inversion dispersion model, middle distance using a Gaussian plume (GP) model and at the landscape scale using the Numerical Atmospheric Modelling Environment (NAME) Inversion Technique for Emission Modelling (InTEM) inversion. The emission estimates derived using the WindTrax and Gaussian plume (GP) approaches agree well for the period of intense observations. Applying the Gaussian plume approach to all periods of elevated measurements seen at Haddenham produces year-round and monthly landfill emission estimates with an estimated annual emission of 11.6 Gg CH 4 yr −1 . The monthly emission estimates are highest in winter (2160 kg h −1 in February) and lowest in summer (620 kg h −1 in July). These data identify the effects of environmental conditions on landfill CH 4 production and highlight the importance of year-round measurements to capture seasonal variability in CH 4 emission.
    Subject code 333
    Language English
    Publishing date 2017-06-29
    Publishing country de
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article: Volatile halocarbon emissions by three tropical brown seaweeds under different irradiances

    Keng, Fiona Seh-Lin / Phang, Siew-Moi / Rahman, Noorsaadah Abd / Leedham, Emma C / Hughes, Claire / Robinson, Andrew D / Harris, Neil R. P / Pyle, John A / Sturges, William T

    Journal of applied phycology. 2013 Oct., v. 25, no. 5

    2013  

    Abstract: The emission rates of eight volatile halogenated compounds by three tropical brown seaweed species collected from Cape Rachado, west coast Peninsular Malaysia, under different irradiances have been determined. A purge-and-trap sample preparation system ... ...

    Abstract The emission rates of eight volatile halogenated compounds by three tropical brown seaweed species collected from Cape Rachado, west coast Peninsular Malaysia, under different irradiances have been determined. A purge-and-trap sample preparation system with a gas chromatograph and mass-selective detector was used to measure a suite of halocarbons released by Sargassum binderi Sonder ex J. Agardh, Padina australis Hauck, and Turbinaria conoides (J. Agardh) Kützing. All species are widely distributed in Peninsular Malaysia, with S. binderi a dominant seaweed species at our survey site. Release of few halocarbons was found to be influenced by irradiance. Correlations were also observed between emission of certain halocarbons with photosynthetic activity, especially bromo-and iodinated compounds (0.6 < r <0.9; p < 0.01) suggesting that environmental factors such as light can affect the release of these volatile halogenated compounds by the seaweeds into the atmosphere. Compared with temperate and polar brown seaweeds, tropical species, such as T. conoides, may emit higher levels of bromoform, CHBr₃, and other halocarbons. It is therefore important to investigate the contribution of tropical seaweeds towards the local atmospheric composition of halocarbons.
    Keywords Sargassum ; atmospheric chemistry ; emissions ; environmental factors ; gas chromatography ; light intensity ; macroalgae ; photosynthesis ; surveys ; Malaysia
    Language English
    Dates of publication 2013-10
    Size p. 1377-1386.
    Publishing place Springer-Verlag
    Document type Article
    ZDB-ID 1002324-0
    ISSN 1573-5176 ; 0921-8971
    ISSN (online) 1573-5176
    ISSN 0921-8971
    DOI 10.1007/s10811-013-9990-x
    Database NAL-Catalogue (AGRICOLA)

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  8. Book ; Online: Estimating the size of a methane emission point-source at different scales

    Riddick, Stuart N. / Connors, Sarah / Robinson, Andrew D. / Manning, Alastair J. / Jones, Pippa S. D. / Lowry, David / Nisbet, Euan / Skelton, Robert L. / Allen, Grant / Pitt, Joseph / Harris, Neil R. P.

    eISSN: 1680-7324

    from local to landscape

    2016  

    Abstract: High methane (CH 4 ) mixing ratios (up to 4 ppm) have occurred sporadically at our measurement site in Haddenham, Cambridgeshire since July 2012. Isotopic measurements and back trajectories show that the source is the Waterbeach Waste management park 7 ... ...

    Abstract High methane (CH 4 ) mixing ratios (up to 4 ppm) have occurred sporadically at our measurement site in Haddenham, Cambridgeshire since July 2012. Isotopic measurements and back trajectories show that the source is the Waterbeach Waste management park 7 km SE of Haddenham. To investigate this further, measurements were made on June 30 th and July 1 st 2015 at other locations nearer to the source. Landfill emissions have been estimated using three different approaches (WindTrax, Gaussian plume, and NAME InTEM inversion) applied to the measurements made close to source and at Haddenham. The emission estimates derived using the WindTrax and Gaussian plume approaches agree well for the period of intense observations. Applying the Gaussian plume approach to all periods of elevated measurements seen at Haddenham produces year-round and monthly landfill emission estimates. The estimated annual emissions vary between 11.6 and 13.7 Gg CH 4 yr −1 . The monthly emission estimates are highest in winter (2160 kg hr −1 in February) and lowest in summer (620 kg hr −1 in July). These data identify the effects of environmental conditions on landfill CH 4 production and highlight the importance of year-round measurement to capture seasonal variability in CH 4 emission. We suggest the landscape inverse modelling approach described in this paper is in good agreement with more labour-intensive near-source approaches and can be used to identify point-sources within an emission landscape to provide high-quality emission estimates.
    Subject code 333
    Language English
    Publishing date 2016-11-22
    Publishing country de
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: Characterisation of particle mass and number concentration on the east coast of the Malaysian Peninsula during the northeast monsoon

    Dominick, Doreena / Mohd. Talib Latif / Juneng, Liew / Khan, Md Firoz / Amil, Norhaniza / Mead, Mohammed Iqbal / Nadzir, Mohd Shahrul Mohd / Phang, Siew Moi / Azizan Abu Samah / Ashfold, Matthew J. / Sturges, William T. / Harris, Neil R.P. / Robinson, Andrew D. / Pyle, John A.

    Atmospheric environment. 2015 Sept., v. 117 p.187-199

    2015  

    Abstract: Particle mass concentrations (PM10, PM2.5 and PM1) and particle number concentration ((PNC); 0.27 μm ≤ Dp ≤ 34.00 μm) were measured in the tropical coastal environment of Bachok, Kelantan on the Malaysian Peninsula bordering the southern edge of the ... ...

    Abstract Particle mass concentrations (PM10, PM2.5 and PM1) and particle number concentration ((PNC); 0.27 μm ≤ Dp ≤ 34.00 μm) were measured in the tropical coastal environment of Bachok, Kelantan on the Malaysian Peninsula bordering the southern edge of the South China Sea. Statistical methods were applied on a three-month hourly data set (9th January to 24th March 2014) to study the influence of north-easterly winds on the patterns of particle mass and PNC size distributions. The 24-h concentrations of particle mass obtained in this study were below the standard values detailed by the Recommended Malaysian Air Quality Guideline (RMAQG), United States Environmental Protection Agency (US EPA) and European Union (EU) except for PM2.5, which recorded a 24-h average of 30 ± 18 μg m−3 and exceeded the World Health Organisation (WHO) threshold value (25 μg m−3). Principal component analysis (PCA) revealed that PNC with smaller diameter sizes (0.27–4.50 μm) showed a stronger influence, accounting for 57.6% of the variability in PNC data set. Concentrations of both particle mass and PNC increased steadily in the morning with a distinct peak observed at around 8.00 h, related to a combination of dispersion of accumulated particles overnight and local traffic. In addition to local anthropogenic, agricultural burning and forest fire activities, long-range transport also affects the study area. Hotspot and backward wind trajectory observations illustrated that the biomass burning episode (around February–March) significantly influenced PNC. Meteorological parameters influenced smaller size particles (i.e. PM1 and Dp (0.27–0.43 μm)) the most.
    Keywords European Union ; United States Environmental Protection Agency ; World Health Organization ; air quality ; atmospheric chemistry ; biomass ; burning ; coasts ; data collection ; forest fires ; guidelines ; meteorological parameters ; monsoon season ; particulates ; principal component analysis ; traffic ; South China Sea ; Aerosols ; Multivariate analysis ; Meteorology ; Long-range transport ; Biomass episodes
    Language English
    Dates of publication 2015-09
    Size p. 187-199.
    Publishing place Elsevier Ltd
    Document type Article ; Online
    ZDB-ID 216368-8
    ISSN 0004-6981 ; 1352-2310
    ISSN 0004-6981 ; 1352-2310
    DOI 10.1016/j.atmosenv.2015.07.018
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  10. Article ; Online: Spatial-temporal variations in surface ozone over Ushuaia and the Antarctic region: observations from in situ measurements, satellite data, and global models.

    Nadzir, Mohd Shahrul Mohd / Ashfold, Matthew J / Khan, Md Firoz / Robinson, Andrew D / Bolas, Conor / Latif, Mohd Talib / Wallis, Benjamin M / Mead, Mohammed Iqbal / Hamid, Haris Hafizal Abdul / Harris, Neil R P / Ramly, Zamzam Tuah Ahmad / Lai, Goh Thian / Liew, Ju Neng / Ahamad, Fatimah / Uning, Royston / Samah, Azizan Abu / Maulud, Khairul Nizam / Suparta, Wayan / Zainudin, Siti Khalijah /
    Wahab, Muhammad Ikram Abdul / Sahani, Mazrura / Müller, Moritz / Yeok, Foong Swee / Rahman, Nasaruddin Abdul / Mujahid, Aazani / Morris, Kenobi Isima / Sasso, Nicholas Dal

    Environmental science and pollution research international

    2017  Volume 25, Issue 3, Page(s) 2194–2210

    Abstract: The Antarctic continent is known to be an unpopulated region due to its extreme weather and climate conditions. However, the air quality over this continent can be affected by long-lived anthropogenic pollutants from the mainland. The Argentinian region ... ...

    Abstract The Antarctic continent is known to be an unpopulated region due to its extreme weather and climate conditions. However, the air quality over this continent can be affected by long-lived anthropogenic pollutants from the mainland. The Argentinian region of Ushuaia is often the main source area of accumulated hazardous gases over the Antarctic Peninsula. The main objective of this study is to report the first in situ observations yet known of surface ozone (O
    MeSH term(s) Air Pollutants/analysis ; Air Pollution/analysis ; Antarctic Regions ; Carbon Monoxide/analysis ; Climate ; Environmental Monitoring ; Ozone/analysis ; Ozone/chemistry ; Photochemical Processes ; Seasons
    Chemical Substances Air Pollutants ; Ozone (66H7ZZK23N) ; Carbon Monoxide (7U1EE4V452)
    Language English
    Publishing date 2017-11-08
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 1178791-0
    ISSN 1614-7499 ; 0944-1344
    ISSN (online) 1614-7499
    ISSN 0944-1344
    DOI 10.1007/s11356-017-0521-1
    Database MEDical Literature Analysis and Retrieval System OnLINE

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