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Artigos de revistas sobre o assunto "Biological Carbon Pum"
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O'Neill, Cameron M., Andrew McC Hogg, Michael J. Ellwood, Bradley N. Opdyke e Stephen M. Eggins. "Sequential changes in ocean circulation and biological export productivity during the last glacial–interglacial cycle: a model–data study". Climate of the Past 17, n.º 1 (15 de janeiro de 2021): 171–201. http://dx.doi.org/10.5194/cp-17-171-2021.
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Abstract. We conduct a model–data analysis of the marine carbon cycle to understand and quantify the drivers of atmospheric CO2 concentration during the last glacial–interglacial cycle. We use a carbon cycle box model, “SCP-M”, combined with multiple proxy data for the atmosphere and ocean, to test for variations in ocean circulation and Southern Ocean biological export productivity across marine isotope stages spanning 130 000 years ago to the present. The model is constrained by proxy data associated with a range of environmental conditions including sea surface temperature, salinity, ocean volume, sea-ice cover and shallow-water carbonate production. Model parameters for global ocean circulation, Atlantic meridional overturning circulation and Southern Ocean biological export productivity are optimized in each marine isotope stage against proxy data for atmospheric CO2, δ13C and Δ14C and deep-ocean δ13C, Δ14C and CO32-. Our model–data results suggest that global overturning circulation weakened during Marine Isotope Stage 5d, coincident with a ∼ 25 ppm fall in atmospheric CO2 from the last interglacial period. There was a transient slowdown in Atlantic meridional overturning circulation during Marine Isotope Stage 5b, followed by a more pronounced slowdown and enhanced Southern Ocean biological export productivity during Marine Isotope Stage 4 (∼ −30 ppm). In this model, the Last Glacial Maximum was characterized by relatively weak global ocean and Atlantic meridional overturning circulation and increased Southern Ocean biological export productivity (∼ −20 ppm during MIS 3 and MIS 2). Ocean circulation and Southern Ocean biological export productivity returned to modern values by the Holocene period. The terrestrial biosphere decreased by 385 Pg C in the lead-up to the Last Glacial Maximum, followed by a period of intense regrowth during the last glacial termination and the Holocene (∼ 600 Pg C). Slowing ocean circulation, a colder ocean and to a lesser extent shallow carbonate dissolution contributed ∼ −70 ppm to atmospheric CO2 in the ∼ 100 000-year lead-up to the Last Glacial Maximum, with a further ∼ −15 ppm contributed during the glacial maximum. Our model results also suggest that an increase in Southern Ocean biological export productivity was one of the ingredients required to achieve the Last Glacial Maximum atmospheric CO2 level. We find that the incorporation of glacial–interglacial proxy data into a simple quantitative ocean transport model provides useful insights into the timing of past changes in ocean processes, enhancing our understanding of the carbon cycle during the last glacial–interglacial period.
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Russo, Vincent M., e John Wright. "Nuclear Magnetic Resonance for Monitoring Carbon Metabolism in Sweet Corn". HortScience 30, n.º 4 (julho de 1995): 889C—889. http://dx.doi.org/10.21273/hortsci.30.4.889c.
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Understanding carbon metabolism can provide insight into physiological processes regulating yield, senescence, and resistance to pathogens in sweet corn (Zea mays L.). This study was conducted to determine if nuclear magnetic resonance (NMR) spectroscopy could be used to monitor changes in carbon metabolism at various growth stages in the shrunken-2 sweet corn cultivar Illini Gold. The 7th, 9th, and 11th stalk internodes were excised at midwhorl (V9), tassel emergence, 50% silking, and fresh-market harvest stages. The rind was removed and the sap expressed. Carbon-NMR spectroscopy was conducted with a 200.7 MHz machine on the expressed sap. From V9 through 50% silking, peaks in spectra were uniformly grouped from ≈61 to ≈104 ppm. At fresh-market stage, additional peaks were found in the spectra at ≈17 to ≈20 ppm, with the majority of peaks found from ≈57 to ≈104 ppm. The biological importance of these changes in carbon metabolism in sweet corn are not clear. Efforts are under way to identify the carbon-based compounds associated with the peaks.
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Buchanan, Pearse J., Richard J. Matear, Andrew Lenton, Steven J. Phipps, Zanna Chase e David M. Etheridge. "The simulated climate of the Last Glacial Maximum and insights into the global marine carbon cycle". Climate of the Past 12, n.º 12 (22 de dezembro de 2016): 2271–95. http://dx.doi.org/10.5194/cp-12-2271-2016.
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Abstract. The ocean's ability to store large quantities of carbon, combined with the millennial longevity over which this reservoir is overturned, has implicated the ocean as a key driver of glacial–interglacial climates. However, the combination of processes that cause an accumulation of carbon within the ocean during glacial periods is still under debate. Here we present simulations of the Last Glacial Maximum (LGM) using the CSIRO Mk3L-COAL (Carbon–Ocean–Atmosphere–Land) earth system model to test the contribution of physical and biogeochemical processes to ocean carbon storage. For the LGM simulation, we find a significant global cooling of the surface ocean (3.2 °C) and the expansion of both minimum and maximum sea ice cover broadly consistent with proxy reconstructions. The glacial ocean stores an additional 267 Pg C in the deep ocean relative to the pre-industrial (PI) simulation due to stronger Antarctic Bottom Water formation. However, 889 Pg C is lost from the upper ocean via equilibration with a lower atmospheric CO2 concentration and a global decrease in export production, causing a net loss of carbon relative to the PI ocean. The LGM deep ocean also experiences an oxygenation ( > 100 mmol O2 m−3) and deepening of the calcite saturation horizon (exceeds the ocean bottom) at odds with proxy reconstructions. With modifications to key biogeochemical processes, which include an increased export of organic matter due to a simulated release from iron limitation, a deepening of remineralisation and decreased inorganic carbon export driven by cooler temperatures, we find that the carbon content of the glacial ocean can be sufficiently increased (317 Pg C) to explain the reduction in atmospheric and terrestrial carbon at the LGM (194 ± 2 and 330 ± 400 Pg C, respectively). Assuming an LGM–PI difference of 95 ppm pCO2, we find that 55 ppm can be attributed to the biological pump, 28 ppm to circulation changes and the remaining 12 ppm to solubility. The biogeochemical modifications also improve model–proxy agreement in export production, carbonate chemistry and dissolved oxygen fields. Thus, we find strong evidence that variations in the oceanic biological pump exert a primary control on the climate.
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Soedarmanto, H., e E. Setiawati. "The Analysis of Plywood Industrial Wastewater Treatment in South Kalimantan". IOP Conference Series: Earth and Environmental Science 950, n.º 1 (1 de janeiro de 2022): 012045. http://dx.doi.org/10.1088/1755-1315/950/1/012045.
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Abstract Plywood industrial wastewater can cause heavy pollution to the environment. The wastewater treatment system will be determined by the parameters of the liquid waste produced. This study was aimed to reduce the wastewater contamination level in the plywood industry. The method consisted of sedimentation, coagulation, flocculation, aeration, sand filtration, activated carbon adsorption, and ion exchange. The wastewater was pumped into the reservoir and conditioned to a pH of 6 – 7 and allowed to stand for 2 (two) hours for sedimentation. The blower with a speed of 50 rpm was turned for aeration. Then the wastewater was sand filtrated and absorbed by activated carbon. The wastewater flowed into the anion-cation resin tank for ion exchange. The treated effluent filtrate was analyzed for Biological Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), Total Suspended Solid (TSS), Phenol, and total ammonia (NH3). The results showed that the decrease of BOD5; COD; TSS; phenol; and NH3 was from 1,426 ppm to 30,5 ppm (97.9%); 2,545.7 to 34.7 ppm (98.6%); 865 ppm to 9.65 ppm (98.9%); 56.98 ppm to 1.45 ppm (97.5%); and 1,652 ppm to 4.56 ppm (99.7%).
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Walia, Abhishek, Preeti Mehta, Shiwani Guleria, Anjali Chauhan e C. K. Shirkot. "Impact of Fungicide Mancozeb at Different Application Rates on Soil Microbial Populations, Soil Biological Processes, and Enzyme Activities in Soil". Scientific World Journal 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/702909.
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The use of fungicides is the continuous exercise particularly in orchard crops where fungal diseases, such as white root rot, have the potential to destroy horticultural crops rendering them unsaleable. In view of above problem, the present study examines the effect of different concentrations of mancozeb (0–2000 ppm) at different incubation periods for their harmful side effects on various microbiological processes, soil microflora, and soil enzymes in alluvial soil (pH 6.8) collected from apple orchards of Shimla in Himachal Pradesh (India). Low concentrations of mancozeb were found to be deleterious towards fungal and actinomycetes population while higher concentrations (1000 and 2000 ppm) were found to be detrimental to soil bacteria. Mancozeb impaired the process of ammonification and nitrification. Similar results were observed for nitrifying and ammonifying bacteria. Phosphorus solubilization was increased by higher concentration of mancozeb, that is, 250 ppm and above. In unamended soil, microbial biomass carbon and carbon mineralization were adversely affected by mancozeb. Soil enzymes, that is, amylase, invertase, and phosphatase showed adverse and disruptive effect when mancozeb used was above 10 ppm in unamended soil. These results conclude that, to lessen the harmful effects in soil biological processes caused by this fungicide, addition of higher amount of nitrogen based fertilizers is required.
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Moreno, Allison R., George I. Hagstrom, Francois W. Primeau, Simon A. Levin e Adam C. Martiny. "Marine phytoplankton stoichiometry mediates nonlinear interactions between nutrient supply, temperature, and atmospheric CO<sub>2</sub>". Biogeosciences 15, n.º 9 (9 de maio de 2018): 2761–79. http://dx.doi.org/10.5194/bg-15-2761-2018.
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Abstract. Marine phytoplankton stoichiometry links nutrient supply to marine carbon export. Deviations of phytoplankton stoichiometry from Redfield proportions (106C : 1P) could therefore have a significant impact on carbon cycling, and understanding which environmental factors drive these deviations may reveal new mechanisms regulating the carbon cycle. To explore the links between environmental conditions, stoichiometry, and carbon cycling, we compared four different models of phytoplankton C : P: a fixed Redfield model, a model with C : P given as a function of surface phosphorus concentration (P), a model with C P given as a function of temperature, and a new multi-environmental model that predicts C : P as a function of light, temperature, and P. These stoichiometric models were embedded into a five-box ocean circulation model, which resolves the three major ocean biomes (high-latitude, subtropical gyres, and tropical upwelling regions). Contrary to the expectation of a monotonic relationship between surface nutrient drawdown and carbon export, we found that lateral nutrient transport from lower C : P tropical waters to high C : P subtropical waters could cause carbon export to decrease with increased tropical nutrient utilization. It has been hypothesized that a positive feedback between temperature and pCO2, atm will play an important role in anthropogenic climate change, with changes in the biological pump playing at most a secondary role. Here we show that environmentally driven shifts in stoichiometry make the biological pump more influential, and may reverse the expected positive relationship between temperature and pCO2, atm. In the temperature-only model, changes in tropical temperature have more impact on the Δ pCO2, atm (∼ 41 ppm) compared to subtropical temperature changes (∼ 4.5 ppm). Our multi-environmental model predicted a decline in pCO2, atm of ∼ 46 ppm when temperature spanned a change of 10 °C. Thus, we find that variation in marine phytoplankton stoichiometry and its environmental controlling factors can lead to nonlinear controls on pCO2, atm, suggesting the need for further studies of ocean C : P and the impact on ocean carbon cycling.
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Boufeldja, Linda, Dennis Brandt, Caroline Guzman, Manon Vitou, Frederic Boudard, Sylvie Morel, Adrien Servent et al. "Effect of Elevated Carbon Dioxide Exposure on Nutrition-Health Properties of Micro-Tom Tomatoes". Molecules 27, n.º 11 (2 de junho de 2022): 3592. http://dx.doi.org/10.3390/molecules27113592.
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(1) Background: The anthropogenically induced rise in atmospheric carbon dioxide (CO2) and associated climate change are considered a potential threat to human nutrition. Indeed, an elevated CO2 concentration was associated with significant alterations in macronutrient and micronutrient content in various dietary crops. (2) Method: In order to explore the impact of elevated CO2 on the nutritional-health properties of tomato, we used the dwarf tomato variety Micro-Tom plant model. Micro-Toms were grown in culture chambers under 400 ppm (ambient) or 900 ppm (elevated) carbon dioxide. Macronutrients, carotenoids, and mineral contents were analyzed. Biological anti-oxidant and anti-inflammatory bioactivities were assessed in vitro on activated macrophages. (3) Results: Micro-Tom exposure to 900 ppm carbon dioxide was associated with an increased carbohydrate content whereas protein, minerals, and total carotenoids content were decreased. These modifications of composition were associated with an altered bioactivity profile. Indeed, antioxidant anti-inflammatory potential were altered by 900 ppm CO2 exposure. (4) Conclusion: Taken together, our results suggest that (i) the Micro-Tom is a laboratory model of interest to study elevated CO2 effects on crops and (ii) exposure to 900 ppm CO2 led to the decrease of nutritional potential and an increase of health beneficial properties of tomatoes for human health.
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G. N. SHREEVANI, A.G. SREENIVAS, R.V. BELADHADI e B.S. JANAGOUDAR. "Environmental change and the phenology of Bt cotton aphid, Aphis gossypii Glover". Journal of Agrometeorology 19, n.º 4 (1 de dezembro de 2017): 312–18. http://dx.doi.org/10.54386/jam.v19i4.597.
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Climate change in terms of increase in atmospheric carbon dioxide and temperature has impact on agriculture including insect pests that minimize the crop yields. To address these impacts, biological studies on aphid, Aphis gossypii Glover on Bt cotton was conducted for six generations during 2013-14 and 2014-15 under different climate change conditions. The results revealed that the biometry of aphid was influenced by increased carbon dioxide (550 ppm CO2) and temperature (rise in 2°C of the prevailing temperature). This was evidenced by decrease in nymphal developmental time (3.67 ± 0.21 days), longevity of adult (9.43 ± 0.41 days), increased fecundity (32.46 ± 0.95) and reduced life cycle (12.28 ± 0.23 days) in the elevated conditions (both 550 ppm CO2 with 32°C as well as in 550 ppm CO2 + 34°C). However, morphometry of aphid showed slight variations in all the treatments but, aphids under elevated conditions showed reduced body size which indicated that the fitness of aphid was effected in the enriched carbon dioxide (CO2) and temperature conditions.
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Mphahlele, Ipoteng Justice, Soraya Phumzile Malinga e Langelihle Nsikayezwe Dlamini. "Combined Biological and Photocatalytic Degradation of Dibutyl Phthalate in a Simulated Wastewater Treatment Plant". Catalysts 12, n.º 5 (30 de abril de 2022): 504. http://dx.doi.org/10.3390/catal12050504.
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The removal of organic pollutant in wastewater has become a major priority in water treatment. In this study, organic pollutant dibutyl phthalate (DBP) has been biologically and photocatalytically degraded in wastewater using modified transition metal dichalcogenides. The as-synthesized nanoparticles were characterized using various characterization techniques, which includes XRD, Raman, FT-IR, SEM, TEM, UV-Vis, XPS, PL, EIS, and photocurrent responses. The nanoparticles synthesized by slightly modified hydrothermal method depicted a hexagonal phase, as evidenced by XRD and Raman analyses. The biological degradation of 69% dibutyl phthalate was achieved. Moreover, the total organic carbon removal efficiency of 70% was further achieved. Incorporating biological and photocatalytic systems significantly improved dibutyl phthalate removal in secondary effluent by three folds when compared to the unilateral operating setup. The optimized parameters such as pH = 7, 5 ppm and DBP concentration with the addition of 10 mg catalysts loading were employed for the photocatalytic degradation of dibutyl phthalate in water. Pristine WS2 exhibited photocatalytic efficiencies of 46% after 60 min illumination. The use of dual system 3% Ce/Gd-WS2 exhibited the highest photodegradation of 85%, with a chemical oxygen demand of 80% and total organic carbon of 77%. The enhanced activity by the composite is attested to the formation of heterojunction exhibiting excellent charge separation and low rate of recombination. The 3% Ce/Gd-WS2 can be used up to seven times and still achieve a degradation of 56%.
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Xue, Z., R. He, K. Fennel, W. J. Cai, S. Lohrenz, W. J. Huang e H. Tian. "Modeling <i>p</i>CO<sub>2</sub> variability in the Gulf of Mexico". Biogeosciences Discussions 11, n.º 8 (27 de agosto de 2014): 12673–95. http://dx.doi.org/10.5194/bgd-11-12673-2014.
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Abstract. A three-dimensional coupled physical–biogeochemical model was used to simulate and examine temporal and spatial variability of surface pCO2 in the Gulf of Mexico (GoM). The model is driven by realistic atmospheric forcing, open boundary conditions from a data-assimilative global ocean circulation model, and observed freshwater and terrestrial nutrient and carbon input from major rivers. A seven-year model hindcast (2004–2010) was performed and was validated against in situ measurements. The model revealed clear seasonality in surface pCO2. Based on the multi-year mean of the model results, the GoM is an overall CO2 sink with a flux of 1.34 × 1012 mol C yr−1, which, together with the enormous fluvial carbon input, is balanced by the carbon export through the Loop Current. A sensitivity experiment was performed where all biological sources and sinks of carbon were disabled. In this simulation surface pCO2 was elevated by ~ 70 ppm, providing the evidence that biological uptake is a primary driver for the observed CO2 sink. The model also provided insights about factors influencing the spatial distribution of surface pCO2 and sources of uncertainty in the carbon budget.
Teses / dissertações sobre o assunto "Biological Carbon Pum"
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Terrats, Louis. "Le flux de carbone particulaire et le lien avec la communauté phytoplanctonique : une approche par flotteurs-profileurs biogéochimiques". Electronic Thesis or Diss., Sorbonne université, 2022. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2022SORUS550.pdf.
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L'Océan est un acteur majeur du climat en échangeant avec l'atmosphère de grandes quantités de carbone. Le carbone atmosphérique est fixé à la surface de l’océan par le phytoplancton qui le transforme en carbone biogène, dont une partie est transportée vers l’océan profond par des mécanismes physiques et biologiques; il s’agit de la Pompe Biologique de Carbone (BCP). Une infime partie de ce carbone biogène atteindra des profondeurs suffisantes pour être séquestré durant plusieurs siècles avant qu'il ne retourne dans l'atmosphère, régulant les concentrations atmosphériques de CO2. Aujourd'hui, nous en savons assez sur la BCP pour reconnaitre son importance dans le climat, mais nos connaissances sur son fonctionnement sont limitées en raison d’un échantillonnage insuffisant des flux de carbone biogène. Dans ce travail de thèse, nous avons utilisé les flotteurs BioGéoChimique-Argo, plateformes d’observations conçues pour résoudre le problème du sous-échantillonnage, afin d’explorer un mécanisme majeur de la BCP qui est la pompe gravitationnelle. La pompe gravitationnelle est le transport du carbone biogène sous la forme de particules organiques (POC) qui sédimentent de la surface vers l’océan profond. Notre étude de la pompe gravitationnelle se divise en trois axes. Le premier axe consiste au développement d’une méthode pour détecter les floraisons de coccolithophoridés, groupe phytoplanctonique majeur qui a potentiellement un contrôle important sur le transport du POC en profondeur. Le deuxième axe est centré sur la variabilité saisonnière et régionale des flux de POC dans l’Océan Austral, qui est une zone sous-échantillonnée mais dans laquelle plusieurs flotteurs ont été déployés avec une trappe optique à sédiments (OST). Seuls une dizaine de flotteurs sont équipés d’OST, ce qui est faible en comparaison avec l’ensemble de la flotte BGC-Argo (i.e. plusieurs centaines de flotteurs). C’est pourquoi nous avons développé, dans le troisième axe, une méthode pour estimer le flux de POC avec les capteurs standards du programme BGC-Argo. Cette méthode a ensuite été appliquée à une centaine de flotteurs pour décrire la variabilité saisonnière du flux de POC dans de nombreuses régions océaniques. Dans ce travail de thèse, nous mettons également en évidence le lien entre la variabilité des flux et la nature des particules en surface. Par exemple, nous avons calculé des relations entre la composition de la communauté phytoplanctonique et les flux de POC à 1000m. En utilisant ces relations, nous avons ensuite utilisé les observations satellites pour extrapoler les flux de POC à de larges échelles spatiales, comme à l’ensemble de l’Océan Austral et de l’océan globalThe ocean plays a key role in the climate by exchanging large quantities of carbon with the atmosphere. Atmospheric carbon is fixed at the ocean surface by phytoplankton that transforms it into biogenic carbon, part of which is transported to the deep ocean by physical and biological mechanisms; this is the Biological Carbon Pump (BCP). A tiny fraction of this biogenic carbon reaches sufficient depths to be sequestered for several centuries before it returns to the atmosphere, thus regulating concentrations of atmospheric CO2. Today, we know enough about the BCP to recognize its importance in climate, but our knowledge of its functioning is limited due to insufficient sampling of biogenic carbon fluxes. Here, we used BioGeoChimical-Argo floats, observational platforms designed to solve the undersampling problem, to explore a major mechanism of the BCP called the gravitational pump. The gravitational pump is the transport of biogenic carbon in the form of organic particles (POC) that sink from the surface into the deep ocean. Our study of the gravitational pump is divided into three axes. The first axis consisted of developing a method to detect blooms of coccolithophores, a major phytoplankton group that potentially has an important control on the transport of POC at depth. The second axis focused on the seasonal and regional variability of POC fluxes in the Southern Ocean, an undersampled area in which several floats have been deployed with an optical sediment trap (OST). Only ten floats were equipped with an OST, which is low compared to the whole BGC-Argo fleet (i.e. several hundred floats). Therefore, in the third axis, we developed a method to estimate the POC flux with the standard sensors of BGC-Argo floats. This method was then applied to hundreds of floats to describe the seasonal variability of the POC flux in many regions. In this study, we also highlighted the link between the POC flux and the nature of surface particles. For example, we calculated relationships between phytoplankton community composition and POC flux at 1000m. Using these relationships, we then used satellite observations to extrapolate POC flux to large spatial scales, such as the entire Southern Ocean and the global ocean
Livros sobre o assunto "Biological Carbon Pum"
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Steinberg, Deborah. Zooplankton Biogeochemical Cycles. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780199233267.003.0006.
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The structure of planktonic communities profoundly affects particle export and sequestration of organic material (the biological pump) and the chemical cycling of nutrients. This chapter describes the integral and multifaceted role zooplankton (both protozoan and metazoan) play in the export and cycling of elements in the ocean, with an emphasis on the North Atlantic Ocean and adjacent seas. Zooplankton consume a significant proportion of primary production across the world's oceans, and their metabolism plays a key role in recycling carbon, nitrogen, and other elements. The chapter also addresses how human or climate-influenced changes in North Atlantic zooplankton populations may in turn drive changes in zooplankton-mediated biogeochemical cycling.
Capítulos de livros sobre o assunto "Biological Carbon Pum"
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Rixen, Tim, Niko Lahajnar, Tarron Lamont, Rolf Koppelmann, Bettina Martin, Luisa Meiritz, Claire Siddiqui e Anja K. Van der Plas. "The Marine Carbon Footprint: Challenges in the Quantification of the CO2 Uptake by the Biological Carbon Pump in the Benguela Upwelling System". In Sustainability of Southern African Ecosystems under Global Change, 729–57. Cham: Springer International Publishing, 2024. http://dx.doi.org/10.1007/978-3-031-10948-5_25.
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AbstractQuantifying greenhouse gas (GHG) emissions is essential for mitigating global warming, and has become the task of individual countries assigned to the Paris agreement in the form of National Greenhouse Gas Inventory Reports (NIR). The NIR informs on GHG emissions and removals over national territory encompassing the 200-mile Exclusive Economic Zone (EEZ). However, apart from only a few countries, who have begun to report on coastal ecosystems, mostly mangroves, salt marshes, and seagrass meadows, the NIR does not cover or report on GHG sources and sinks of the 200-mile exclusive economic zone which, for Namibia and South Africa includes the Benguela Upwelling System (BUS). Based on our results, we estimated a CO2 uptake by the biological carbon pump of 18.5 ± 3.3 Tg C year−1 and 6.0 ± 5.0 Tg C year−1 for the Namibian and South African parts of the BUS, respectively. Even though it is assumed that the biological carbon pump already responds to global change and fisheries, uncertainties associated with estimates of the CO2 uptake by the biological carbon pump are still large and hamper a thorough quantification of human impacts on the biological carbon pump. Despite these uncertainties, it is suggested to include parameters such as preformed nutrient supply, carbon export rates, Redfield ratios, and CO2 concentrations measured at specific key sites into the NIR to stay focussed on the biological carbon pump and to support research addressing open questions, as well as to improve methods and observing concepts.
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Glaeser, Robert M., Kenneth Downing, David DeRosier, Wah Chiu e Joachim Frank. "Specimen Preparation". In Electron Crystallography Of Biological Macromolecules, 139–66. Oxford University PressNew York, NY, 2007. http://dx.doi.org/10.1093/oso/9780195088717.003.0006.
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Abstract The first step in preparing a sample for electron microscopy (or electron diffraction) is to mount it in an appropriate way, so that it can be put onto the specimen stage in the objective lens. The majority of specimen preparation procedures involve the use of thin metal grids, normally 300 mesh (300 holes per inch) or 400 mesh copper (molybdenum, titanium) grids, which are used to support some type of continuous, thin film (Bozzola and Russell, 1999; Hayat, 2000). Evaporated carbon films, 5 to 30 nm in thickness, are usually the most appropriate support film. Thin polymer films, which in turn should be stabilized by an additional layer of evaporated carbon, are also useful for many routine purposes.
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Dolman, Han. "The Carbon Cycle". In Biogeochemical Cycles and Climate, 129–58. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198779308.003.0009.
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The chapter first shows carbon dioxide variability over long geological timescales. The current stocks and fluxes of carbon are then given, for the whole planet and for the atmosphere, ocean and land separately. The main flows of carbon in the ocean, through the biological pump (via uptake through photosynthesis) and the physical pump (via involving chemical transformation uptake in water and production of carbonate), and on land, through photosynthesis (Gross Primary Production) and respiration leading to Net Primary Production, Net Ecosystem Production and Net Biome Production and through the storage of carbon in biomass, are described. Next, carbon interactions during the Paleocene–Eocene Thermal Maximum and glacial–interglacial transitions, thought to involve changes in ocean circulation and upwelling, are examined. The key changes from anthropogenic perturbation of the natural carbon cycle are shown to be due to fossil fuel burning and land-use change (deforestation). The effects of the carbon–climate feedback on temperature and carbon stocks are also shown.
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Kirchman, David L. "Carbon Pumps in the Oceans". In Microbes, 48–71. Oxford University PressNew York, 2024. http://dx.doi.org/10.1093/oso/9780197688564.003.0004.
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Abstract Climate change would be a lot worse if not for the carbon dioxide (and heat) taken up by the ocean via carbon pumps, the largest being the biological pump. Phytoplankton carbon is exported to deep waters by particles such as zooplankton fecal pellets, marine snow, and other aggregates and by dissolved organic carbon (DOC). As part of the microbial carbon pump, bacteria contribute to the formation of refractory DOC that is 6000 years old. As carbon dioxide increases in the ocean, another gas, dissolved oxygen, is decreasing. Oceanic deoxygenation is caused by warming seawater and by bacterial activity stimulated by global warming. The worry is that bacteria are using refractory DOC that had sequestered carbon away from the atmosphere for thousands of years. Even if climate change doesn’t alter the ocean’s contribution to carbon sequestration, it seems likely to disrupt microbial communities that are the base of life in the ocean.
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Kumar Ameta, Rakesh. "Carbon-Based Nanomaterials for Sensing Applications". In Recent Advances in Biosensor Technology, 30–44. BENTHAM SCIENCE PUBLISHERS, 2023. http://dx.doi.org/10.2174/9789815123739123010005.
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: Recently, carbon-based nanomaterials (CBNM) have been widely used for chemical and biosensing applications due to their outstanding physicochemical properties, such as mechanical, thermal, optical, electrical and structural diversity. Such materials include carbon nanotubes, graphene oxide, graphene quantum dots and fullerene. As a consequence of inimitable features, these give superior strength, electrical conductivity, and flexibility toward numerous chemical and biological objects, which is valuable for chemical sensing and biosensing purposes. However, the specific intrinsic property makes graphene and carbon nanotubes (CNTs) most attractive among the various allotropes of carbon. Since the environmental contaminants in ppm level affect the people, therefore the use of CBNM for environmental sensing provides an accessible cache of data for modelling, which makes it easy to monitor environmental challenges. Thus, the biological, chemical, thermal, stress, optical, strain and flow sensors deliver a larger surface area, excellent electrical conductivity with chemical constancy, as well as mechanical difficulty with straightforward functionalization pathways of CNTs to improve old-style carbon electrode sensor platforms. Therefore, in this chapter, the CBNM for sensing purposes are focused in detail on their mechanism.
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Kirchman, David L. "Microbial Solutions". In Microbes, 151–76. Oxford University PressNew York, 2024. http://dx.doi.org/10.1093/oso/9780197688564.003.0009.
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Abstract Microbes can help to reduce fossil fuel use, minimize the release of methane and nitrous oxide, and take carbon dioxide out of the atmosphere. Biomethane made by archaea is an important fuel source in many developing countries, while ethanol made by yeast makes up 10 percent or more of fuel used in cars in the United States and elsewhere. Inhibiting methanogenesis could reduce methane emissions from cattle and rice cultivation. Environmental microbiome engineering may lower nitrogen fertilizer use and release of nitrous oxide. Several strategies for taking carbon dioxide out of the atmosphere, known as negative emissions, rely on bacteria and fungi to form soil organic matter. One geoengineering scheme is to fertilize the Southern Ocean with iron to strengthen the biological pump and draw down atmospheric carbon dioxide. These possible solutions illustrate why understanding and solving today’s most important environmental problem, climate change, depends on microbes.
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Lahiri, Susmita, Debarati Ghosh e Jatindra Nath Bhakta. "Role of Microbes in Eco-Remediation of Perturbed Aquatic Ecosystem". In Handbook of Research on Inventive Bioremediation Techniques, 70–107. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-2325-3.ch004.
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Anthropogenic and natural hazards put aquatic ecosystem under severe stress due to organic and inorganic pollutants and calls for remediation. Eco-remediation, an ecological blessing for ecosystem stabilization refers to the restoration of the perturbing ecosystem to its original balanced state with a multi-purpose approaches for removing pollutants by vast array of biological components. Aquatic habitats and biodiversity are adversely affected by indiscriminate pollution along with rising levels of carbon dioxide. To overcome the aquatic stress of various pollutants, microorganisms significantly imparting crucial roles in environmentally sustainable bioremediation approaches by adapting themselves in order to survive in perturbed ecosystems resulting in the environmental remediation. This chapter attempts to deal with eco-remediation of ecosystems perturbed by various hazardous pollutants by focusing the degrading and transforming of contaminants into less toxic forms by microbes and carbon sequestration through heterotrophic pathway applying different ex situ or in situ detoxifying mechanisms. Considering the high eco-remedial efficiencies, microbial eco-remediation technologies could be applied as an emerging approach in restoring perturbed aquatic ecosystems in ecological engineering systems.
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Lahiri, Susmita, Debarati Ghosh e Jatindra Nath Bhakta. "Role of Microbes in Eco-Remediation of Perturbed Aquatic Ecosystem". In Oceanography and Coastal Informatics, 25–61. IGI Global, 2019. http://dx.doi.org/10.4018/978-1-5225-7308-1.ch002.
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Anthropogenic and natural hazards put aquatic ecosystem under severe stress due to organic and inorganic pollutants and calls for remediation. Eco-remediation, an ecological blessing for ecosystem stabilization refers to the restoration of the perturbing ecosystem to its original balanced state with a multi-purpose approaches for removing pollutants by vast array of biological components. Aquatic habitats and biodiversity are adversely affected by indiscriminate pollution along with rising levels of carbon dioxide. To overcome the aquatic stress of various pollutants, microorganisms significantly imparting crucial roles in environmentally sustainable bioremediation approaches by adapting themselves in order to survive in perturbed ecosystems resulting in the environmental remediation. This chapter attempts to deal with eco-remediation of ecosystems perturbed by various hazardous pollutants by focusing the degrading and transforming of contaminants into less toxic forms by microbes and carbon sequestration through heterotrophic pathway applying different ex situ or in situ detoxifying mechanisms. Considering the high eco-remedial efficiencies, microbial eco-remediation technologies could be applied as an emerging approach in restoring perturbed aquatic ecosystems in ecological engineering systems.
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Holbourn, Ann, Wolfgang Kuhnt, Karlos G. D. Kochhann, Kenji M. Matsuzaki e Nils Andersen. "Middle Miocene climate–carbon cycle dynamics: Keys for understanding future trends on a warmer Earth?" In Understanding the Monterey Formation and Similar Biosiliceous Units across Space and Time. Geological Society of America, 2022. http://dx.doi.org/10.1130/2022.2556(05).
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ABSTRACT The late early to middle Miocene period (18–12.7 Ma) was marked by profound environmental change, as Earth entered into the warmest climate phase of the Neogene (Miocene climate optimum) and then transitioned to a much colder mode with development of permanent ice sheets on Antarctica. Integration of high-resolution benthic foraminiferal isotope records in well-preserved sedimentary successions from the Pacific, Southern, and Indian Oceans provides a long-term perspective with which to assess relationships among climate change, ocean circulation, and carbon cycle dynamics during these successive climate reversals. Fundamentally different modes of ocean circulation and carbon cycling prevailed on an almost ice-free Earth during the Miocene climate optimum (ca. 16.9–14.7 Ma). Comparison of δ13C profiles revealed a marked decrease in ocean stratification and in the strength of the meridional overturning circulation during the Miocene climate optimum. We speculate that labile polar ice sheets, weaker Southern Hemisphere westerlies, higher sea level, and more acidic, oxygen-depleted oceans promoted shelf-basin partitioning of carbonate deposition and a weaker meridional overturning circulation, reducing the sequestration efficiency of the biological pump. X-ray fluorescence scanning data additionally revealed that 100 k.y. eccentricity-paced transient hyperthermal events coincided with intense episodes of deep-water acidification and deoxygenation. The in-phase coherence of δ18O and δ13C at the eccentricity band further suggests that orbitally paced processes such as remineralization of organic carbon from the deep-ocean dissolved organic carbon pool and/or weathering-induced carbon and nutrient fluxes from tropical monsoonal regions to the ocean contributed to the high amplitude variability of the marine carbon cycle. Stepwise global cooling and ice-sheet expansion during the middle Miocene climate transition (ca. 14.7–13.8 Ma) were associated with dampening of astronomically driven climate cycles and progressive steepening of the δ13C gradient between intermediate and deep waters, indicating intensification and vertical expansion of ocean meridional overturning circulation following the end of the Miocene climate optimum. Together, these results underline the crucial role of the marine carbon cycle and low-latitude processes in driving climate dynamics on an almost ice-free Earth.
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Gehlen, Marion, e Nicolas Gruber. "Biogeochemical Consequences of Ocean Acidification and Feedbacks to the Earth System". In Ocean Acidification. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199591091.003.0017.
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By the year 2008, the ocean had taken up approximately 140 Gt carbon corresponding to about a third of the total anthropogenic CO2 emitted to the atmosphere since the onset of industrialization (Khatiwala et al. 2009 ). As the weak acid CO2 invades the ocean, it triggers changes in ocean carbonate chemistry and ocean pH (see Chapter 1). The pH of modern ocean surface waters is already 0.1 units lower than in pre-industrial times and a decrease by 0.4 units is projected by the year 2100 in response to a business-as- usual emission pathway (Caldeira and Wickett 2003). These changes in ocean carbonate chemistry are likely to affect major ocean biogeochemical cycles, either through direct pH effects or indirect impacts on the structure and functioning of marine ecosystems. This chapter addresses the potential biogeochemical consequences of ocean acidification and associated feedbacks to the earth system, with focus on the alteration of element fluxes at the scale of the global ocean. The view taken here is on how the different effects interact and ultimately alter the atmospheric concentration of radiatively active substances, i.e. primarily greenhouse gases such as CO2 and nitrous oxide (N2O). Changes in carbonate chemistry have the potential for interacting with ocean biogeochemical cycles and creating feedbacks to climate in a myriad of ways (Box 12.1). In order to provide some structure to the discussion, direct and indirect feedbacks of ocean acidification on the earth system are distinguished. Direct feedbacks are those which directly affect radiative forcing in the atmosphere by altering the air–sea flux of radiatively active substances. Indirect feedbacks are those that first alter a biogeochemical process in the ocean, and through this change then affect the air–sea flux and ultimately the radiative forcing in the atmosphere. For example, when ocean acidification alters the production and export of organic matter by the biological pump, then this is an indirect feedback. This is because a change in the biological pump alters radiative forcing in the atmosphere indirectly by first changing the nearsurface concentrations of dissolved inorganic carbon and total alkalinity.
Trabalhos de conferências sobre o assunto "Biological Carbon Pum"
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Tabeta, Shigeru, e Haruki Yoshimoto. "Investigation of Carbon Budget Around Artificial Upwelling Generator by a Coupled Physical-Biological Model". In ASME 2007 26th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2007. http://dx.doi.org/10.1115/omae2007-29653.
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There are several projects of generating upwelling by artificial structures to enhance the primary production expecting fish catch increase. From the view point of global environment, CO2 budget between atmosphere and ocean due to such technologies are also interesting. In this study, a coupled physical-biological model was developed to simulate the nitrogen and carbon cycles around artificial upwelling generator. The model is focusing on the degradation of particulate organic matter, because the process should much affects on the efficiency of the biological pump. The model is tuned by using the experimental data and applied to simulate the material cycle in the target area which is located north of Ikitsuki Island located northwest of Kyusyu, Japan, where an artificial seabed mound is installed to generate upwelling. The long-term carbon budget is also estimated by vertical one-dimensional ecosystem model using the parameters determined from the results of the three-dimensional coupled physical-biological model.
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Subramanian, Karthikeyan, e Gopi Sankar. "A Review on Hydrogen Fuel and Storage System Product Design for PEM Fuel Cell Vehicle Applications". In International Conference on Automotive Materials and Manufacturing AMM 2023. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2023. http://dx.doi.org/10.4271/2023-28-1335.
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<div class="section abstract"><div class="htmlview paragraph">As a future sustainable fuel, hydrogen will significantly reduce reliance on fossil energy resources as well as the amount of exhaust emitted by automobiles. It is a carbon-free fuel, and it can be produced through a number of conversion technologies, including thermochemical, electrochemical, and biological processes. However, with advanced PEM fuel cell technologies to drive commercialization and commercial vehicle growth, hydrogen fuel quality for efficient fuel cell system performance, and fuel storage system product design with all safety features are the unique selling points. Though the concept of the hydrogen storage system for fuel cell electric vehicles (FCEV) is derived from global technologies, it cannot be implemented directly in the Indian CV (commercial vehicle) market. A certain level of technology can only be transmitted. In light of the aforementioned scenario, the vehicle manufacturers should prioritise the focus on selection of well-organized strategies for hydrogen storage systems and usage of hydrogen fuel from competent production techniques with improved fuel quality. Hence, it is significant to study the hydrogen fuel production process, quality, impact of impurities on fuel cell vehicle performance, together with storage tank design requirements and mitigation approach without compromising the quality of the FC vehicle performances. Accordingly, in this review, regardless of firm type, for transforming the FCEV market opportunities into a commercially viable FCEV product are discussed in this paper.</div></div>
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Squibb, Carson, LoriAnne Groo, Adrian Bialy e Michael Philen. "Biologically Inspired Fluidic Flexible Matrix Composite Pumps for Wave Energy Conversion". In ASME 2016 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/smasis2016-9321.
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Inspired by the fibrillar network in plant cell walls and the helical fibers found in soft bodied hydrostats (e.g. worms, squid, elephant trunks, and octopus arms), fluidic flexible matrix composites (F2MCs) are composite tubes that consist of multiple layers of oriented, high performance fibers, such as carbon, precisely placed in a flexible matrix resin to form high-mechanical advantage actuators and variable stiffness materials. Unique to the F2MC tube is its ability to generate high pressures and volume change with a small external load as a result of the stiff reinforcement fiber orientation in the wall of the tube and the soft supporting elastomer. When a load is applied to the tubes, the volume of the composite pump is reduced and fluid is forced out of the tube by the reinforcing fibers. The objective of this research is to design, fabricate and characterize F2MCs for use in wave energy conversion where ocean waves provide the axial load to drive fluid through the pumps. F2MCs pumps are tested in a water basin and mechanically cycled between 0 Hz and 2 Hz at up to 17 percent strain. Instantaneous input power is found by measuring the displacement and applied force to the actuators, while output power values are derived from pressure and flow rate measurements at the tube outlet. From these measurements the actuator efficiency is subsequently determined.
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Trikis, Spyridon, Vaibhav Sumant, Muhammad Arshad, Anna Olliver, Meshaal Jarallah Abushereeda e John Brown. "Implementation of Odour Control Systems for Nuisance-free and Public Friendly Environment in Qatar". In The 2nd International Conference on Civil Infrastructure and Construction. Qatar University Press, 2023. http://dx.doi.org/10.29117/cic.2023.0164.
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The Public Works Authority (Ashghal) is contributing to the development of Qatar with the construction of first class, sustainable infrastructure with a high degree of public acceptance by utilizing best international practices. Pumping stations and sewage treatment works are traditionally constructed at the outskirts of cities, as they are generally associated with odour nuisance; however, as the cities are expanded, the facilities become part of the urban fabric and their operation becomes an issue of concern for nearby residents. To address this public concern, Ashghal has for its sewer infrastructure adopted odour emission limits as stringent as 0.5ppbV of hydrogen sulphide (H2S) and 0.5ouE/m3 of odour concentration, which are lower than recognisable levels by humans. Moreover, on the way to FIFA World Cup Qatar 2022™, Ashghal decided to install environmentally friendly and sustainable biological treatment units followed by activated carbon filters to ensure a nuisance-free environment at the existing Doha South Sewage Treatment Works (DS-STW) and the new Doha South Terminal Pump Station (DS-TPS). This paper presents methodologies for determining odour levels in existing and new units, available odour treatment technologies, and the selected treatment schemes for the above projects.
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Dimić, Dušan, Dejan Milenković, Edina Avdović, Goran Kaluđerović e Jasmina Dimitrić Marković. "MOLECULAR DOCKING AND MOLECULAR DYNAMICS STUDIES OF THE INTERACTION BETWEEN COUMARIN-NEUROTRANSMITTER DERIVATIVES AND CARBONIC ANHYDRASE IX". In 1st INTERNATIONAL Conference on Chemo and BioInformatics. Institute for Information Technologies, University of Kragujevac,, 2021. http://dx.doi.org/10.46793/iccbi21.056d.
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Novel biologically active compounds can be obtained by the structural modification of coumarins. In this contribution, five new derivatives of 4-hydroxycoumarin with tyramine, octopamine, norepinephrine, 3-methoxytyramine, and dopamine were obtained. Their structures were optimized based on the previously obtained crystal structure of the 4-hydroxycoumarin-dopamine derivative. The special emphasis was put on the effect of various substituents on the structure of obtained compounds and intramolecular interactions governing the stability. To investigate their possible antitumor activity, molecular docking and molecular dynamics simulations were performed with Carbonic anhydrase, a prognostic factor in several cancers, and compared to the native ligand, 5-acetamido-1,3,4-thiadiazole- 2-sulfonamide. The results have shown that all of the coumarin-neurotransmitter derivatives bind to the active pocket of protein with the binding energies higher than for the native ligand. The main contributions to the binding energies were discussed. The Root Mean Square Deviation (RMSD), Root Mean Square Fluctuation (RMSF), and Radius of gyration (Rg), as results of MD simulations, were used to predict the activity of compounds towards chosen protein. The highest MD binding energies were obtained for the derivatives with dopamine and 3-methoxytyramine, with the van der Waals interaction and hydrogen bonds being the most important contributors.
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Krishnamoorthi, M., S. Sreedhara e Pavan Prakash Duvvuri. "Modelling of Soot Formation and Experimental Study for Different Octane Number Fuels in Dual Fuel Combustion Engine With Diesel". In ASME 2020 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/icef2020-2914.
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Abstract This work investigates the effects of low reactivity fuel (LRF) on reactivity controlled compression ignition (RCCI) engine with fossil diesel. RCCI mode of combustion is a low temperature combustion (LTC) strategy which reduces both oxides of nitrogen (NOx) and soot emissions simultaneously. Syngas and methanol can be obtained from renewable biological resources and conventional coal. LRF (methanol, syngas and gasoline) has been supplied to the engine along with intake air and diesel is injected to initiate the combustion process. Test engine has been operated for different dual fuel modes at constant engine speed (1500 rpm) and load (80%). Closed cycle combustion simulations have been performed to complement the experimental results and in-cylinder dynamics. Particle size mimic (PSM) model has been used to investigate the soot particle number and mass-size distributions and mean particle size. Results confirmed that maximum gross indicated thermal efficiency (38%) has been observed in gasoline/diesel dual fuel mode. Compared to gasoline/diesel dual fuel mode, about 74% and 86%, lower soot and NOx emissions have been observed for methanol/diesel dual fuel mode, while about 46% and 52% lower soot and NOx emissions have been found in syngas/diesel mode. About 53% higher carbon monoxide emission has been observed for syngas/diesel case as compared to gasoline/diesel case. Predictions from soot modelling reveal that condensation mode, surface growth mode and nucleation mode particles are dominant in methanol, syngas and gasoline/diesel dual fuel modes respectively. Bigger primary soot particles (diameter > 35 nm, nanometre) have been observed for methanol/diesel mode and the gasoline/diesel mode shows a smaller size of primary particles.
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A˚mand, Lars-Erik, Bo Leckner, Solvie Herstad Sva¨rd, Marianne Gyllenhammar, David Eskilsson e Claes Tullin. "Co-Combustion of Pulp- and Paper Sludge With Wood: Emissions of Nitrogen, Sulphur and Chlorine Compounds". In 17th International Conference on Fluidized Bed Combustion. ASMEDC, 2003. http://dx.doi.org/10.1115/fbc2003-097.
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Sludge from wastewater treatment plants in five Swedish pulp and paper mills has been burned together with wood in a circulating fluidised bed (CFB) boiler. The sludge was either mechanically dewatered or pre-dried. The mechanically dewatered sludge had to be fed with a pump, but the pre-dried sludge could be fed by the fuel feed system normally used for coal, wood chips or wood pellets. In parallel to the combustion tests in the CFB boiler the sludges were also investigated as single fuels in a small laboratory FB. The Swedish pulp and paper industry produces three major fractions of sludge: pure fibre sludge, sludge produced by employing a precipitation species like ironaluminiumsulphate, and finally, sludge subjected to biological cleaning. The way of production of the sludge influences its content of, for example, nitrogen, sulphur and chlorine, but the composition of the sludge is also influenced by the pulp and paper process. The present measurements show that the concentrations of nitrogen, sulphur and chlorine in the sludge have a great impact on the corresponding gaseous emissions from combustion. Actions to prevent these emissions could be necessary, depending on the origin of the sludge and treatment process used. In the present project all sludges were burned with wood-pellets as the main fuel under identical operating conditions, typical for a CFB boiler. Wood pellets were chosen as a well defined, low-polluting fuel that makes comparison of emissions from the sludges clear. Co-combustion with wood-pellets has the advantage of enabling operation also with wet sludges that cannot be used as single fuels without pre-drying. No actions were taken to improve sulphur and chlorine retention, by for example adding limestone. From a combustion point of view the co-combustion works well with low levels of carbon monoxide present in the flue gas and no light hydrocarbons.
Relatórios de organizações sobre o assunto "Biological Carbon Pum"
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Buesseler, Ken O., Di Jin, Melina Kourantidou, David S. Levin, Kilaparti Ramakrishna e Philip Renaud. The ocean twilight zone’s role in climate change. Woods Hole Oceanographic Institution, fevereiro de 2022. http://dx.doi.org/10.1575/1912/28074.
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The ocean twilight zone (more formally known as the mesopelagic zone) plays a fundamental role in global climate. It is the mid-ocean region roughly 100 to 1000 meters below the surface, encompassing a half-mile deep belt of water that spans more than two-thirds of our planet. The top of the ocean twilight zone only receives 1% of incident sunlight and the bottom level is void of sunlight. Life in the ocean twilight zone helps to transport billions of metric tons (gigatonnes) of carbon annually from the upper ocean into the deep sea, due in part to processes known as the biological carbon pump. Once carbon moves below roughly 1000 meters depth in the ocean, it can remain out of the atmosphere for centuries to millennia. Without the benefits of the biological carbon pump, the atmospheric CO 2 concentration would increase by approximately 200 ppm 1 which would significantly amplify the negative effects of climate change that the world is currently trying to curtail and reverse. Unfortunately, existing scientific knowledge about this vast zone of the ocean, such as how chemical elements flow through its living systems and the physical environment, is extremely limited, jeopardizing the efforts to improve climate predictions and to inform fisheries management and ocean policy development.
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Tsikos, Hariloas, Sipesihle Rafuza, Zolane R. Mhlanga, Paul B. H. Oonk, Vlassis Papadopoulos, Adrian C. Boyce, Paul R. D. Mason, Christopher Harris, Darren R. Gröcke e Timothy W. Lyons. Carbon isotope evidence for water-column carbon and iron cycling in the Paleoproterozoic ocean and implications for the early biological pump: supplementary data file. Rhodes University, Department of Geology, 2020. http://dx.doi.org/10.21504/10962/138395.
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Bécu, V., A.-A. Sappin e S. Larmagnat. User-friendly toolkits for geoscientists: how to bring geology experts to the public. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/331220.
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A growing number of countries are committed toreduce their carbon emissions and are transitioning towards renewable and clean energy sources, leading to an in crease in demand formetals and minerals. This is especially the case for a short list of what are called "critical minerals" which are considered essential to economic development, including the transition to a low-carbon economy and national security. There liability of their supply chain raises concerns considering geological scarcity, difficulty to extract and/or political factors influencing their availability. At the same time, public awareness and perception of geoscience are eroding and there is more and more reluctance towards mining projects, even from traditionally favourable communities. To face this challenge, promote public interest and outline the contribution of geological science to society, geoscientists of the Geological Survey of Canada (GSC-Québec) have designed and put together a portable display that includes a suite of mineral and metal samples considered critical for the sustainable success of Canada's transition towards a clean and digital economy. The display is a user-friendly toolkit that can be used by any GSC geoscientists during outreach activities, in classrooms as well as during public open houses. It comes with straightforward pedagogic material and content, along with presentation scenarios. To broaden and adapt the workshops to specific expectations, additional toolkits were developed and all are contained within easy to carry travel cases. These cover a variety of topics and can be presented as stand-alone displays or be used complementary to one another. For example, the "Mines and minerals" collection may serve as a supplement to the "Critical minerals" display to present every day objects in which minerals are used as well as ores amples from active mines to illustrate the intertwining between mining activities and our everyday lives. Another display covers the ever-popular fossils thematic with the "Sedimentary rocks and fossils" collection and gives an opportunity to address key geoscience themes such as life evolution and biological crisis along with groundwater reservoirs and resources. The "Magmatic rocks" display touches on the formation of rocks from magmas, the different types and active processes of volcanoes, and discusses the risks and benefits related to volcanic activity. Hopefully, these four ready-to-use portable displays will encourage more GSC geoscientists to engage in public oriented activities to make geosciences more accessible, change perceptions and offer an overall tangible scientific experience for people.
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Artificial upwelling: More power for the ocean’s biological carbon pump. CDRmare, 2023. http://dx.doi.org/10.3289/cdrmare.31.
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Knowledge summary, Artificial upwelling: More power for the ocean’s biological carbon pump. CDRmare, 2023. http://dx.doi.org/10.3289/cdrmare.30.
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Algae, zooplankton and fish are among the key players in the biological carbon pump that allows the ocean to naturally remove carbon dioxide from the atmosphere and store it at great depths. However, for this mechanism to function optimally, it needs nutrients, which are lacking in many places, at least in the light-flooded surface water. By pumping up nutrient-rich deep water, humans could remedy this nutrient deficiency. But whether artificial upwelling would actually have an effect on the climate, what risks it would entail and whether it could be technically and legally implemented on a large scale, is still uncertain. The research mission CDRmare provides