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Showing 1 to 17 of 17 for “"Levoglucosan"”.
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Quantification and Reduction of Exposure to Residential Woodsmoke Particulate Matter
… of seven selected chemical tracers of woodsmoke (levoglucosan, dehydroabietic acid, abietic acid, vanillin, acetovanillone, guaiacol, and 4-ethylguaiacol) in particulate matter. This method was used to analyze particulate matter collected in Libby, MT, a community where woodsmoke is the …
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Quantification and Reduction of Exposure to Residential Woodsmoke Particulate Matter
… of seven selected chemical tracers of woodsmoke (levoglucosan, dehydroabietic acid, abietic acid, vanillin, acetovanillone, guaiacol, and 4-ethylguaiacol) in particulate matter. This method was used to analyze particulate matter collected in Libby, MT, a community where woodsmoke is the …
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Transformation of biomass to value-added chemicals through non-thermal plasma
… by pyrolysis. It showed that the maximum levoglucosan yield from the NTP pretreated cellulose was 78.6 wt%, compared to 58.2 wt% by pyrolyzing untreated cellulose. Comprehensive analysis of the NTP pretreated cellulose showed that homolytic cleavage of glycosidic bonds occur during the NTP …
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The pre-treatment and pyrolysis of biomass for the production of liquids for fuels and speciality chemicals
… have selectively increased the yield of levoglucosan from 2.45 to 18.58 mf wt.% [dry feedstock basis]. Additive techniques have selectively increased the yield of hydroxyacetaldehyde from 7.26 to 11.63 mf w.% [dry feedstock basis]. Techno-economic assessment has been carried out on an …
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Density Functional Theory Calculations Complement Mass Spectrometry Experiments in the Investigation of Biomass Fast Pyrolysis and Ion-Molecule Reaction Mechanisms
… with the well-established mechanism of levoglucosan production via nucleophilic attack of the hydroxymethylene group at the anomeric carbon concerted with glycosidic bond cleavage. Computational investigation on the reaction barriers of this reducing end unraveling mechanism in tandem …
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Primary and secondary emissions from upland fires in Ireland
… and total carbon TC) and molecular biomarkers (levoglucosan, mannosan, galactosan, 4-Nitrocatechol 4-NC, 4-Nitrophenol 4-NP and 4-Nitroguaiacol 4-NG). Emission factors of measured gases were as follows: CO: 42 g/kg (heather), 27 g/kg (moor grass) and 80 g/kg (gorse); CO2 1167 g/kg (heather), …
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Lab-scale fast-hydropyrolysis and vapor-phase catalytic hydrodeoxygenation for producing liquid fuel range hydrocarbons from intact biomass
… of the cellulose pyrolysis liquid products. Levoglucosan and its isomers, cellobiosan, water and light oxygenates like formic acid, glycolaldehyde and hydroxyacetone are the major products of cellulose fast-pyrolysis. Increasing pyrolysis temperature in the range of 480 °C to 580 °C was found …
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Catalytic Pyrolysis of Cellulose, Hemicellulose and Lignin Model Compounds
… NaOH pretreatment caused elimination of the levoglucosan fraction while increasing the aromatic fraction. The NaOH pretreated cellulose pyrolyzed on sand reduced the levoglucosan groups while increasing the aromatic fraction of the bio oil. In the hemicellulose studies, birchwood xylan and …
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Deciphering Biomass Fragmentation using Millisecond Microreactor Kinetics
… of six major product compounds including levoglucosan, furfural and 2-methoxyphenol. Levoglucosan (LGA), a six-carbon oxygenate, is the most abundant primary product from cellulose pyrolysis with LGA yields reported over a wide range of 5−80 percent carbon (%C). In this study, the …
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Aqueous-phase Organic Chemistry in the Atmosphere
… CIMS was further applied to the OH oxidation of levoglucosan, using a high mass resolution CIMS. Unique reaction trends were observed, from which novel mechanism analysis frameworks were introduced. Aqueous-phase photochemical processing of a variety of light-absorbing organic compounds (Brown …
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Evaluation of management practices and remediation techniques for improving water quality in agricultural systems
… Polysaccharide-derived compounds, dominated by levoglucosan, tended to decrease over the growing season in all the treatments, and were lower in the BR treatment. Examination of a wide range of simulated agricultural effluents showed that short-term BOD measurements (BOD2 and BOD5) significantly …
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Polymer pyrolysis and oxidation studies in a continuous feed and flow reactor : cellulose, polystyrene, and polyethylene
… of NaCl (5% of Cl) shows higher decomposition of levoglucosan and more rapid conversion of major initial products to CO and CO_2. Formation of major initial products, C_6 oxygenated species, hydrocarbons (C_5-C_7), furan derivatives (C_4 and C_5), and light species (C_1 - C_4) are somewhat …
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The aging of organic aerosol in the atmosphere : chemical transformations by heterogeneous oxidation
… oxidation of pure erythritol (C4H1 00 4 ) and levoglucosan (C6H1 00 5) particles by hydroxyl radical (OH) was studied first in order to evaluate the effects of atmospheric aging on the mass and chemical composition of atmospheric organic aerosol, particularly that resembling fresh secondary …
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Pirólisis catalítica de materiales celulósicos para la obtención de compuestos de alto valor agregado
… farmacéutica, como los son los anhidroazúcares levoglucosan y levoglucosenona. También se estudia el residuo carbonoso remanente en los experimentos de pirólisis. Se presentan los resultados para la celulosa microcristalina (capítulo 3) y pulpa de papel Kraft (capítulo 4). En estos capítulos se …
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An Assessment of Indoor Infiltration Parameters for Black Carbon from Residential Wood Combustion and the Spectral Dependence of Light Absorption for Organic Carbon
… analyzed for tracers for woodsmoke, including levoglucosan, elemental carbon, and organic carbon. Aethalometers measured black carbon, an indicator of carbon combustion. Additional PEMS and aethalometers were placed inside one residential home to better understand infiltration of woodsmoke. To …
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Uncovering the Potential of Utilising Terrestrial Biogenic Markers in Ice Cores as Proxies to Past Environmental Conditions
… and pinic acid, and a biomass burning marker; levoglucosan. This thesis details the development and optimisation of a highly sensitive, high-performance liquid chromatographic mass spectrometry (HPLC-MS) method for the quantification of the ten target compounds that has achieved limit of …