The Role of Surface Area in Catalytic Gasification of Biomass

Gasification of biomass has the potential to provide a carbon-negative source of liquid fuels. The current limited use of gasification is due in part to the high temperatures necessary to achieve high conversion levels. These temperatures can be lowered by the use of catalysts, but the mechanisms by which catalysts affect the reaction rate are not fully understood. Here, the structural component of potassium carbonate’s role in the gasification process was examined. Samples of pinewood sawdust were impregnated with potassium carbonate, then pyrolyzed with N2 in a fixed bed reactor at 750°C (heater thermocouple reading). Half of the char was washed with deionized water twice to remove potassium ions. The char was ground to a 150 micron diameter. Gasification of the samples was performed using CO2 at 750°C and 900°C. Reaction rates over time were compared to the reaction rate of pure pinewood sawdust char. The pure char was then impregnated with K2CO3 and gasified, allowing a comparison to be made between the efficacy of impregnating the sawdust versus the char. Results show that after washing, the impregnated char shows similar or decreased reactivity compared to the pure char. Preliminary results do suggest that impregnation of the sawdust leads to greater reactivity over time than impregnation of the char. The results do not suggest a strong influence of surface area change during impregnation on the reactivity of the char

Performance on Indirect Measures of Race Evaluation Predicts Amygdala Activation

We used fMRI to explore the neural substrates involved in the unconscious evaluation of Black and White social groups. Specifically, we focused on the amygdala, a subcortical structure known to play a role in emotional learning and evaluation. In Experiment 1, White American subjects observed faces of unfamiliar Black and White males. The strength of amygdala activation to Black-versus-White faces was correlated with two indirect (unconscious) measures of race evaluation (Implicit Association Test [IAT] and potentiated startle), but not with the direct (conscious) expression of race attitudes. In Experiment 2, these patterns were not obtained when the stimulus faces belonged to familiar and positively regarded Black and White individuals. Together, these results suggest that amygdala and behavioral responses to Black-versus-White faces in White subjects reflect cultural evaluations of social groups modified by individual experience.Psycholog

Airborne In-Situ Measurements of Formaldehyde Over California: One Year of Results from the Compact Formaldehyde Fluorescence Experiment (COFFEE) Instrument

Formaldehyde (HCHO) is one of the most abundant oxygenated volatile organiccompounds (VOCs) in the atmosphere, playing a role in multiple atmosphericprocesses, such as ozone (O3) production in polluted environments. Due toits short lifetime of only a few hours in daytime, HCHO also serves astracer of recent photochemical activity. While photochemical oxidation ofnon-methane hydrocarbons is the dominant source, HCHO can also be emitteddirectly from fuel combustion, vegetation, and biomass burning. The CompactFormaldehyde FluorescencE Experiment (COFFEE) instrument was built forintegration onto the Alpha Jet Atmospheric eXperiment (AJAX) payload, basedout of NASAs Ames Research Center (Moffett Field, CA). Using Non-ResonantLaser Induced Fluorescence (NR-LIF), trace concentrations of HCHO can bedetected with a sensitivity of 200 parts per trillion.Since its first research flight in December 2015, COFFEE has successfullyflown on more than 20 science missions throughout California and Nevada.Presented here are results from these flights, including boundary layermeasurements and vertical profiles throughout the tropospheric column.Californias San Joaquin Valley is a primary focus, as this region is knownfor its elevated levels of HCHO as well as O3. Measurements collected inwildfire plumes, urban centers, agricultural lands, and on and off shorecomparisons will be presented. In addition, the correlation of HCHO to othertrace gases also measured by AJAX, including O3, methane, carbon dioxide,and water vapor will also be shown. Lastly, the implications of these HCHOmeasurements on calibration and validation of remote sensing data collectedby NASAs OMI (Aura) and OMPS (SuomiNPP) satellites will be addressed

Airborne In-Situ Measurements of Formaldehyde Over California: First Results from the Compact Formaldehyde Fluorescence Experiment (COFFEE) Instrument

Formaldehyde (HCHO) is one of the most abundant oxygenated volatile organic compounds (VOCs) in the atmosphere, playing a role multiple atmospheric processes. Measurements of HCHO can be used to help quantify convective transport, the abundance of VOCs, and ozone production in urban environments. The Compact Formaldehyde FluorescencE Experiment (COFFEE) instrument uses Non-Resonant Laser Induced Fluorescence (NR-LIF) to detect trace concentrations of HCHO as part of the Alpha Jet Atmospheric eXperiment (AJAX) payload. Developed at NASA GSFC, COFFEE is a small, low maintenance instrument with a sensitivity of 100 pptv and a quick response time (1 sec). The COFFEE instrument has been customized to fit in an external wing pod on the Alpha Jet aircraft based at NASA ARC. The instrument can operate over a broad range of altitudes, from boundary layer to lower stratosphere, making it well suited for the Alpha Jet, which can access altitudes from the surface up to 40,000 ft. Results of the first COFFEE science flights preformed over the California's Central Valley will be presented. Boundary layer measurements and vertical profiles in the tropospheric column will both be included. This region is of particular interest, due to its elevated levels of HCHO, revealed in satellite images, as well as its high ozone concentrations. In addition to HCHO, the AJAX payload includes measurements of atmospheric ozone, methane, and carbon dioxide. Formaldehyde is one of the few urban pollutants that can be measured from space. Plans to compare in-situ COFFEE data with satellite-based HCHO observations such as those from OMI (Aura) and OMPS (SuomiNPP) will also be presented

Investigating the acceptability of non-mesh, long-lasting insecticidal nets amongst nomadic communities in Garissa County, Kenya using a prospective, longitudinal study design and cross-sectional household surveys.

BACKGROUND: North East Kenya is an area of semi-arid terrain, prone to malaria epidemics. The distribution of long-lasting insecticidal nets (LLINs) has long been a key malaria intervention, however, for nomadic populations who live and sleep outside, in harsh climates and areas with increasing reports of exophagic behaviour of mosquitoes, traditional LLINs are often inadequate. This study investigates the acceptability of non-mesh LLINs, specifically designed to suit nomadic, outdoor sleeping communities. METHODS: In September 2011, 13,922 non-mesh LLINs were distributed to 8,511 nomadic households in Garissa County, North East Province, Kenya. A prospective, longitudinal study design was used to assess the acceptability of this novel type of LLIN. Cross-sectional household surveys, focus group discussions (FGDs), and key informant interviews (KIs) were used to collect data on attitudes and practices regarding the Dumuria nets. RESULTS: A very high level of acceptability was reported with 95.3% of respondents stating they liked the nets. Of the factors reportedly determining net use the most frequently mentioned was "vulnerability". Of those with concerns about the nets, the colour (white) was the most frequently reported. CONCLUSION: The tailoring of LLINs to specific communities and contexts leads to increased levels of acceptability. Large-scale, blanket net distribution campaigns, which are currently the standard practice, do not cater for the specific and nuanced needs of the differing communities they often serve. This non-mesh LLIN offers a highly effective and desirable malaria prevention option to a typically hard to reach and underserved nomadic population at increased risk of malaria infection