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Soil sampling pits across three hillslope positions - toeslope, backslope, and summit - were dug in 2020 in watershed N4D (burned every 4 years) and N1D (burned annually) to characterize the impacts of woody encroachment on subsurface soil physical, chemical, and biological properties. Pits were hand-dug to 120 cm in the toeslope position and to 60 cm deep at the backslope and summit positions. Soil pits in N4D were dug directly under dogwood shrubs (Cornus drumondii) while pits in N1B were dug under grasses and forbs. Soil pit faces were photographed to determine root fractions with depth, soil monoliths were take to charaterize soil macroporosity with depth while soil cores were taken in each horizon for water retention analysis. Soil sensors were also installed at four soil depths at the toeslope position and 3 soil depths at the backslope and summit positions to record half hourly soil moisture, soil temperature, soil water potential, soil electrical conductivity, and soil carbon dioxide, and soil oxygen. In addition, geophysical measurements were taken in N4D using time-lapse electrical resistivity.
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Selective Hydrogenation of Aromatic Hydrocarbons over Noble Metal Catalysts
Reaction mechanisms for selective hydrogenation of aromatic hydrocarbons to cycloolefins and cycloalkanes over noble metal catalysts were studied at the molecular level. Reactive intermediates were identified by combining experimental IR and Raman spectroscopic measurements with DFT calculations and related to catalytic activity and selectivity differences. Improved catalyst formulations were developed.
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- Award ID(s):
- 2219872
- PAR ID:
- 10611630
- Publisher / Repository:
- https://aiche.confex.com/aiche/nams25/meetingapp.cgi/Paper/705486
- Date Published:
- Format(s):
- Medium: X
- Location:
- Atlanta, Georgia, USA
- Sponsoring Org:
- National Science Foundation
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Soil sampling pits across three hillslope positions - toeslope, backslope, and summit - were dug in 2020 in watershed N4D (burned every 4 years) and N1D (burned annually) to characterize the impacts of woody encroachment on subsurface soil physical, chemical, and biological properties. Pits were hand-dug to 120 cm in the toeslope position and to 60 cm deep at the backslope and summit positions. Soil pits in N4D were dug directly under dogwood shrubs (Cornus drumondii) while pits in N1B were dug under grasses and forbs. Soil pit faces were photographed to determine root fractions with depth, soil monoliths were take to charaterize soil macroporosity with depth while soil cores were taken in each horizon for water retention analysis. Soil sensors were also installed at four soil depths at the toeslope position and 3 soil depths at the backslope and summit positions to record half hourly soil moisture, soil temperature, soil water potential, soil electrical conductivity, and soil carbon dioxide, and soil oxygen. In addition, geophysical measurements were taken in N4D using time-lapse electrical resistivity in 2023.more » « less
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Material testing includes concrete compressive strength test and steel tension coupon tests. Concrete cylinder tests were conducted to measure the compressive strength of concrete used for composite slab on MST specimen at different days. Nine 4”x8” concrete cylinders were casted for compressive strength tests. Compressive strength for different days; 14, 21, and 28, were conducted. Compressive strength tests were conducted following ASTM C39. The test were conducted in-house at Lehigh University. Steel tension coupon tests were conducted to measure the material properties of collector specimens and MST shear tab. Plate type 2” gage length tension coupons were used for tensile strength testing. Coupons were extracted from flanges of TFW and AFW specimens, web and shear tab of MST specimen. The tensile strength testings were conducted following ASTM E8.more » « less
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Abstract Background More details about human movement patterns are needed to evaluate relationships between daily travel and malaria risk at finer scales. A multiagent mobility simulation model was built to simulate the movements of villagers between home and their workplaces in 2 townships in Myanmar. Methods An agent-based model (ABM) was built to simulate daily travel to and from work based on responses to a travel survey. Key elements for the ABM were land cover, travel time, travel mode, occupation, malaria prevalence, and a detailed road network. Most visited network segments for different occupations and for malaria-positive cases were extracted and compared. Data from a separate survey were used to validate the simulation. Results Mobility characteristics for different occupation groups showed that while certain patterns were shared among some groups, there were also patterns that were unique to an occupation group. Forest workers were estimated to be the most mobile occupation group, and also had the highest potential malaria exposure associated with their daily travel in Ann Township. In Singu Township, forest workers were not the most mobile group; however, they were estimated to visit regions that had higher prevalence of malaria infection over other occupation groups. Conclusions Using an ABM to simulate daily travel generated mobility patterns for different occupation groups. These spatial patterns varied by occupation. Our simulation identified occupations at a higher risk of being exposed to malaria and where these exposures were more likely to occur.more » « less
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Climatological data were collected from the C1 climate station on Niwot Ridge (3018 m elevation) throughout the year. From 2000-06-24 to 2013-03-25, data were recorded using a Campbell Instruments CR23X data logger. Starting 2013-03-27, data were recorded using a Campbell Instruments CR1000 data logger. Maximum and minimum values were recorded instantaneously, with a sampling interval of 5 seconds. Daily means and totals were calculated from 17,280 individual measurements. The CR23X logger was programmed to generate both hourly and daily output. The CR1000 logger generated daily, hourly, and minute data until 2014-09-10, when these time periods were discontinued and only 10 minute raw data were collected.more » « less
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