... the stream was degraded in habitat value and stream function, and it posed a threat to the infrastructure of the high school campus on which the segment was located. ... the project provides ...myriad opportunities for education and outreach of SARA staff, JISD students, and the community at large.
High temperature inorganic membranes may play an important role in the development of economical processes for pre-combustion and/or post-combustion CO₂ capture. The CO₂/N₂ selectivity of mesoporous ...silica membranes is enhanced by surface modification using APTS (3-aminopropyl-triethoxy silane). Unmodified silica membranes exhibit Knudsen diffusion behavior for most gases but also have some contribution from surface diffusion of heavier or interacting gases like CO₂, CH₄, etc. Gas separation experiments were performed on the modified membranes for both pure gas and mixed gases for a range of temperatures and feed gas compositions. Mixed gas separation factors as high as 10 for CO₂ over N₂ were observed at 393K and CO₂ partial pressures of 15kPa; whereas for pure gases (CO₂ partial pressure of 303kPa), no separation was seen. The hypothesized transport mechanism is the reaction of CO₂ with surface amine groups to form a carbamate species and subsequent surface “hopping” of carbon dioxide. The CO₂ binding at ambient conditions is sufficiently strong to greatly inhibit the surface diffusion of CO₂, however, as the temperature increases, the CO₂ permeance increases and selective transport of CO₂ is observed. The permeance of CO₂ is highly non-linear, and increases with decreasing CO₂ partial pressure in the feed gas. NMR studies performed on the bare support and modified membrane shows the support has been modified by APTS. Pore size analysis on the unmodified and modified silica substrates show that the pore diameter of modified substrates are lower than that of the unmodified substrate indicating that the amine silanes are anchored on the pore walls of the substrate. The NMR measurement for an APTS/silica membrane with adsorbed CO₂ shows the presence of a carbamate species and thus supports the hypothesized reaction mechanism or facilitated solid-state CO₂ transport. The binding energy for CO₂ adsorption is 15.5kcal/mol and activation energy for CO₂ diffusion/hopping from one amine group to another of APTS is 7.2kcal/mol as computed using ab initio Density Functional Theory (DFT).
Abstract Background/Purpose Gastroschisis is a resource-intensive birth defect without consensus regarding optimal surgical and medical management. We sought to determine best-practice guidelines by ...examining differences in multi-institutional practices and outcomes. Methods Site-specific practice patterns were queried, and infant–maternal chart review was retrospectively performed for gastroschisis infants treated at 5 UCfC institutions (2007–2012). The primary outcome was length of stay. Univariate analysis was done to assess variation practices and outcomes by site. Multivariate models were constructed with site as an instrumental variable and with sites grouped by silo practice pattern adjusting for confounding factors. Results Of 191 gastroschisis infants, 164 infants were uncomplicated. Among uncomplicated patients, there were no deaths and only one case of necrotizing enterocolitis. Bivariate analysis revealed significant differences in practices and outcomes by site. Despite wide variations in practice patterns, there were no major differences in outcome among sites or by silo practice, after adjusting for confounding factors. Conclusions Wide variability exists in institutional practice patterns for infants with gastroschisis, but poor outcomes were not associated with expeditious silo or primary closure, avoidance of routine paralysis, or limited central line and antibiotic durations. Development of clinical pathways incorporating these practices may help standardize care and reduce health care costs.
Liver disease is a leading cause of HIV-related mortality. Hepatitis C virus (HCV)-related fibrogenesis is accelerated in the setting of HIV coinfection, yet the mechanisms underlying this aggressive ...pathogenesis are unclear. We identified formalin-fixed paraffin-embedded liver tissue for HIV-infected patients, HCV-infected patients, HIV/HCV-coinfected patients, and controls at Duke University Medical Center. De-identified sections were stained for markers against the wound repair Hedgehog (Hh) pathway, resident T-lymphocytes, and immune activation and cellular aging. HIV infection was independently associated with Hh activation and markers of immune dysregulation in the liver tissue.
High temperature inorganic membranes may play an important role in the development of economical processes for pre-combustion and/or post-combustion CO sub(2 capture. The CO) sub(2)/N sub(2 ...selectivity of mesoporous silica membranes is enhanced by surface modification using APTS (3-aminopropyl-triethoxy silane). Unmodified silica membranes exhibit Knudsen diffusion behavior for most gases but also have some contribution from surface diffusion of heavier or interacting gases like CO) sub(2), CH sub(4, etc. Gas separation experiments were performed on the modified membranes for both pure gas and mixed gases for a range of temperatures and feed gas compositions. Mixed gas separation factors as high as 10 for CO) sub(2) over N sub(2 were observed at 393 K and CO) sub(2) partial pressures of 15 kPa; whereas for pure gases (CO sub(2 partial pressure of 303 kPa), no separation was seen. The hypothesized transport mechanism is the reaction of CO) sub(2) with surface amine groups to form a carbamate species and subsequent surface "hopping" of carbon dioxide. The CO sub(2 binding at ambient conditions is sufficiently strong to greatly inhibit the surface diffusion of CO) sub(2), however, as the temperature increases, the CO sub(2 permeance increases and selective transport of CO) sub(2) is observed. The permeance of CO sub(2 is highly non-linear, and increases with decreasing CO) sub(2) partial pressure in the feed gas. NMR studies performed on the bare support and modified membrane shows the support has been modified by APTS. Pore size analysis on the unmodified and modified silica substrates show that the pore diameter of modified substrates are lower than that of the unmodified substrate indicating that the amine silanes are anchored on the pore walls of the substrate. The NMR measurement for an APTS/silica membrane with adsorbed CO sub(2 shows the presence of a carbamate species and thus supports the hypothesized reaction mechanism or facilitated solid-state CO) sub(2) transport. The binding energy for CO sub(2 adsorption is 15.5 kcal/mol and activation energy for CO) sub(2) diffusion/hopping from one amine group to another of APTS is 7.2 kcal/mol as computed using ab initio Density Functional Theory (DFT).
▶ Synthesized inorganic membranes by surface modification of silica substrate with 3-aminopropyltriethoxysilane APTS ▶ Characterized the membrane using NMR and pore size analysis ▶ CO
2/N
2 ...separation factor as high as 10 was obtained using the modified membranes ▶ The binding energy for CO
2 adsorption is 15.5
kcal/mol and activation energy for CO
2 diffusion/hopping from one amine group to another of APTS is 7.2
kcal/mol as computed using ab initio Density Functional Theory (DFT).
High temperature inorganic membranes may play an important role in the development of economical processes for pre-combustion and/or post-combustion CO
2 capture. The CO
2/N
2 selectivity of mesoporous silica membranes is enhanced by surface modification using APTS (3-aminopropyl-triethoxy silane). Unmodified silica membranes exhibit Knudsen diffusion behavior for most gases but also have some contribution from surface diffusion of heavier or interacting gases like CO
2, CH
4, etc. Gas separation experiments were performed on the modified membranes for both pure gas and mixed gases for a range of temperatures and feed gas compositions. Mixed gas separation factors as high as 10 for CO
2 over N
2 were observed at 393
K and CO
2 partial pressures of 15
kPa; whereas for pure gases (CO
2 partial pressure of 303
kPa), no separation was seen. The hypothesized transport mechanism is the reaction of CO
2 with surface amine groups to form a carbamate species and subsequent surface “hopping” of carbon dioxide. The CO
2 binding at ambient conditions is sufficiently strong to greatly inhibit the surface diffusion of CO
2, however, as the temperature increases, the CO
2 permeance increases and selective transport of CO
2 is observed. The permeance of CO
2 is highly non-linear, and increases with decreasing CO
2 partial pressure in the feed gas. NMR studies performed on the bare support and modified membrane shows the support has been modified by APTS. Pore size analysis on the unmodified and modified silica substrates show that the pore diameter of modified substrates are lower than that of the unmodified substrate indicating that the amine silanes are anchored on the pore walls of the substrate. The NMR measurement for an APTS/silica membrane with adsorbed CO
2 shows the presence of a carbamate species and thus supports the hypothesized reaction mechanism or facilitated solid-state CO
2 transport. The binding energy for CO
2 adsorption is 15.5
kcal/mol and activation energy for CO
2 diffusion/hopping from one amine group to another of APTS is 7.2
kcal/mol as computed using ab initio Density Functional Theory (DFT).
The design and status of the diode-pumped 10 Hz, 150 J, 150 fs, 1 PW laser system under development for the Matter in Extreme Conditions Upgrade (MEC-U) project will be presented.
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