67 research outputs found
Bats of Hot Springs National Park, Arkansas
A survey was conducted from June 1982 through January 1987 to determine the occurrence of bat species in Hot Springs National Park, Garland County, Arkansas; an area of approximately 2025 hectares. A total of 309 bats in the families Molossidae and Vespertilionidae were captured. Species represented included: Eptesicus fuscus, Lasiurus borealis, Lasiurus cinereus, Nycticeius humeralis, Pipistrellus subflavus, and Tadarida brasiliensis cynocephala
Nucleation in hydrophobic cylindrical pores : a lattice model
We consider the nucleation process associated with capillary condensation of
a vapor in a hydrophobic cylindrical pore (capillary evaporation). The
liquid-vapor transition is described within the framework of a simple lattice
model. The phase properties are characterized both at the mean-field level and
using Monte-Carlo simulations. The nucleation process for the liquid to vapor
transition is then specifically considered. Using umbrella sampling techniques,
we show that nucleation occurs through the condensation of an asymmetric vapor
bubble at the pore surface. Even for highly confined systems, good agreement is
found with macroscopic considerations based on classical nucleation theory. The
results are discussed in the context of recent experimental work on the
extrusion of water in hydrophobic pores
Arkansas Range Extensions of the Seminole Bat (Lasiurus seminolus) and Eastern Big-eared Bat (Plecotus rafinesquii) and Additional County Records for the Hoary Bat (Lasiurus cinereus), Silver-Haired Bat (Lasionycteris noctivagans) and Evening Bat...
Distribution and Habitat of Utilization of the Four-toed Salamander, Hemidactylium scutatum, in the Ouachita Mountains of Arkansas
Four-toed salamanders in Arkansas represent a disjunct population separated from their main range in the eastern United States and Canada. Until recently, the distribution of this species was documented by a few individual specimens collected or observed from widely spaced localities which has resulted in its being considered rare and vulnerable. Recent investigations of distribution and habitat utilization indicate this species may be more common than previously believed, but also reaffirms the need to protect riparian habitat, springs, ponds, woodland seeps and other preferred, moist habitats containing mossy areas used as primary egg deposition sites
Intrusion and extrusion of water in hydrophobic mesopores
We present experimental and theoretical results on intrusion-extrusion cycles
of water in hydrophobic mesoporous materials, characterized by independent
cylindrical pores. The intrusion, which takes place above the bulk saturation
pressure, can be well described using a macroscopic capillary model. Once the
material is saturated with water, extrusion takes place upon reduction of the
externally applied pressure; Our results for the extrusion pressure can only be
understood by assuming that the limiting extrusion mechanism is the nucleation
of a vapour bubble inside the pores. A comparison of calculated and
experimental nucleation pressures shows that a proper inclusion of line tension
effects is necessary to account for the observed values of nucleation barriers.
Negative line tensions of order are found for our
system, in reasonable agreement with other experimental estimates of this
quantity
- …