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Showing 1 to 20 of 23 for “"pyrogenic"”.

  1. Biogeochemical Alteration of Particulate Pyrogenic Organic Carbon (pyC)

    Stuart, Jason Matthew2017

    <p>The resistance of plant derived pyrogenic organic carbon (<em>py</em>C) to abiotic and biotic means of degradation has led to increased interest in the role of <em>py</em>C as a potential carbon sink, as well as a strategy for sequestering atmospheric CO2 to mitigate excess carbon emissions. …

    usm Repository record

  2. A Study on Photodegradation and The Fate of Pyrogenic Carbon

    Howell, John Thomas2015

    … on the order of 1.3 million tons of dissolved pyrogenic carbon (<em>py</em>DOC) could be entering the northern Gulf of Mexico annually. Assessing the fate of <em>py</em>DOC in aquatic systems is crucial to understanding ecosystem impacts and potential feedback to climate change. Current …

    usm Repository record

  3. Dynamic Light Scattering for the Characterization of Polydisperse Fractal Systems by the Example of Pyrogenic Silica

    Kätzel, UweTechnische Universität Dresden

    … used for the characterization of suspensions of pyrogenic silica which consists of fractal-like aggregates composed of sintered spherical primary particles. These structural features clearly complicate the understanding of DLS experiments and have been a severe obstacle to employing DLS as …

    qucosa-diss

  4. ELEVATED PYROGENIC ORGANIC MATTER IN SEDIMENTS FROM LAKE BOSUMTWI, GHANA AS A PROXY FOR THE TERMINATION OF THE AFRICAN HUMID PERIOD

    Zigah, Michael PaulEast Carolina University2025

    … show a relative increase in the abundance of pyrogenic organic matter and suggests increased wildfires in northern Africa before the end of the AHP. The proportion of soot to charcoal in Lake Bosumtwi sediments suggests increased distal wildfire activity and aeolian transport of soot before …

    ecu Repository record

  5. Understanding Functional Silica Additives for HDPE Composite Materials

    Alghfeli, MohammadUniversity of Cambridge2024

    … project was to study the impact of nanoscale pyrogenic silica additives on high-density polyethylene (HDPE) for the potential use as a liner material against corrosion in challenging environments such as oil and gas pipelines. The main body of work involves the analysis of the chemistry of …

    cambridge Repository record

  6. The Influence of Amorphous, Sub-Micrometer Silica Particles in Cement Pastes and Mortars with Very Low Water-to-Cement Ratios (Ultra-High Performance Concrete)

    Oertel, TinaUniversität Bayreuth

    … strength of UHPC are examined. Silica fume, pyrogenic silica and silica synthesized by hydrolysis and condensation of alkoxy silanes, so-called Stoeber particles, are employed. These materials are characterized by measurements of the specific surface area, surface silanol group density, total …

    bayreuth Repository record

  7. Molecular and isotopic records of combustion inputs to the environment over the last 250 years

    Lima, Ana Lucia Cessel deMassachusetts Institute of Technology and Woods Hole Oceanographic Institution2004

    … generated a high-resolution historical record of pyrogenic PAH emissions since pre-industrial times from anoxic aquatic sediments, allowing for detailed comparison with energy consumption data. We show that an increase in PAH concentrations over the last decade may be due to a rise in emissions …

    woods-hole Repository record

  8. Molecular and isotopic records of the combustion inputs to the environment over the last 250 yrs

    Lima, Ana Lúcia Cessel de, 1969-Massachusetts Institute of Technology2004

    … generated a high-resolution historical record of pyrogenic PAH emissions since pre-industrial times from anoxic aquatic sediments, allowing for detailed comparison with energy consumption data. We show that an increase in PAH concentrations over the last decade may be due to a rise in emissions …

    mit Repository record

  9. Space Use and Survival of White-Tailed Deer in a Disturbance-Driven System Containing a Restored Apex Predator

    Ellsworth, William HunterVirginia Tech2020

    … and bottom-up forces, including frequent pyrogenic and hydrological disturbances and the threat of predation. These forces affect their space use, behavior, and survival. Recent changes to the regional hydrology and increased abundances the Florida panther (Puma concolor coryi), their …

    vt Repository record

  10. Biomarkers of Human Exposure and Effect to Petrogenic Polycyclic Aromatic Hydrocarbons

    Yap, Dianne Aster YunqueThe University of Texas Medical Branch at Galveston2021

    … after the DWH oil spill were predicated on pyrogenic PAHs commonly produced through combustion processes that are not representative of the petrogenic PAHs found in oil. Using an optimized Chemically Activated LUciferase gene eXpression (CALUX) bioassay, highly bioactive PAHs in …

    utmb Repository record

  11. Biomass burning emissions on regional-global scales

    Akagi, Sheryl Kashi

    … comprehensive tabulation of EF for known pyrogenic species based on measurements made in smoke that has not yet undergone significant photochemical processing. All EFs are converted to one standard form (grams of compound emitted per kg dry biomass burned) and are categorized into 14 fuel …

    montana-tech Repository record

  12. Biomass burning emissions on regional-global scales

    Akagi, Sheryl Kashi

    … comprehensive tabulation of EF for known pyrogenic species based on measurements made in smoke that has not yet undergone significant photochemical processing. All EFs are converted to one standard form (grams of compound emitted per kg dry biomass burned) and are categorized into 14 fuel …

    montana Repository record

  13. Soil Microbial Community Dynamics In Florida Scrub Ecosystem

    Albarracin, Maria

    Pyrogenic ecosystems are maintained by fires which vary in frequency, seasonality, and intensity. Florida oak-saw palmetto scrub ecosystem is characterized by fires occurring at intervals of 10-20 years. Diverse factors as private land acquisition and development has created a patchy distribution …

    ucf

  14. Negative Effects Of ComMycorrhizal Networks And Roots On Upland Oak Seedlings In Open-Canopy Woodlands And Closed-Canopy Forests

    Bailey, William Chase2019

    … are in danger of being replaced by a mix of non-pyrogenic and shade tolerant tree species that benefit from fire suppression. Successful advanced regeneration by oaks in forests and woodlands depends both on the persistence of seedlings in the shade and growth within canopy gaps. Through the …

    mississippi Repository record

  15. An Evaluation of the Effects of Marine Oil-spills, Remediation Strategies, and Shipwrecks on Microbial Community Structure and Succession

    Thomas, Gareth EUniversity of Essex2021

    … Oak), in Chapter Five, revealed low levels of pyrogenic polycyclic aromatic hydrocarbons and little evidence of HCB, indicating sediments showed no long-term impact by previous oil-pollution from the shipwreck. This thesis not only advances our understanding of microbial response to oil-spills, …

    essex Repository record

  16. A Continental-Scale Investigation of Factors Controlling the Vulnerability of Soil Organic Matter in Mineral Horizons to Decomposition

    Weiglein, Tyler LorenzVirginia Tech2019

    … by nitrogen (N) availability, while an index of pyrogenic C had a negative effect on kfast in both horizons. These results reinforce the recognized need to explicitly represent SOM stabilization via interactions with non-crystalline minerals in ESMs, and they also suggest that increased N inputs …

    vt Repository record

  17. Detection of staphylococcal enterotoxins in patients with rheumatoid arthritis or closed fracture

    Grace, Laura, Taylor, Adam, Bukhari, Marwan, Lauder, BobLancaster Medical School2016

    … and alpha haemolysin (AH), members of the pyrogenic toxin superantigen family (PTSAg). To develop a novel mass spectrometry method to analyse and compare urine samples from patients with rheumatoid arthritis (RA) and orthopaedic fracture patients for the presence of Staphylococcus aureus. …

    lancaster Repository record

  18. Fire and herbivory effects on soil organic carbon stocks and soil greenhouse gas emissions from South African grasslands and savannas: Implications for global change

    Chikomba, FaraiDepartment of Biological Sciences2022

    … SOC pool by addition of mostly recalcitrant pyrogenic organic C, thereby lowering CO2 and N2O fluxes. CH4 fluxes would be increased by the fire induced death of methanotrophic bacteria. To explore this, we examined SOC stocks, soil CO2, CH4 and N2O fluxes including other soil and …

    cape-town Repository record

  19. Fire disturbance belowground: untangling consequences for soil food webs and organic matter

    Pressler, Yamina, author, Moore, John C., advisor, Cotrufo, M. Francesca, advisor, Knapp, Alan K., committee member, Balgopal, Meena M., committee memberColorado State University. Libraries2019

    … particular, fires transform organic matter into pyrogenic carbon (PyC), a recalcitrant material with a dense aromatic structure and long residence times in soils. In natural ecosystems, soil food webs interact with PyC produced after a fire. In agroecosystems, PyC, in the form of biochar, is also …

    colostate Repository record

  20. Monitoring of Persistent Organic Pollutants (POPs) in marine biota from the Catania Gulf (Sicily, Italy) and development of new sensitive analytical methods for their detection

    BUA, ROSARIA ORNELLAUniversità degli studi di Catania2020

    … PAHs, suggesting a mixture of petrogenic and pyrogenic sources. Considering that the data reported in literature are very few and controversial, the results obtained by this preliminary study clearly indicate the need of additional and in-depth investigations. Finally, a new method for the …

    catania Repository record

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