Open Access. Powered by Scholars. Published by Universities.®
- Institution
Articles 1 - 4 of 4
Full-Text Articles in Biology
Rare And Endangered Plants At Gateway National Recreation Area: A Case For Protection Of Urban Natural Areas, Richard Stalter, Michael D. Byer, John T. Tanacredi Ph.D.
Rare And Endangered Plants At Gateway National Recreation Area: A Case For Protection Of Urban Natural Areas, Richard Stalter, Michael D. Byer, John T. Tanacredi Ph.D.
Faculty Works: CERCOM
The diversity of native plant species in urban environments is usually overlooked when biodiversity levels are considered. Inventories of native plants reveal many to be rare species surviving the harsh conditions encountered in urban ecosystems. Knowledge of their existence and an inventory of their distribution will assist in maintaining these populations. Protection strategies for rare plant species are outlined for urban National Parks.
Reconnecting The Sciences, John Eggebrecht, Raymond Dagenais, Don Dosch, Norman J. Merczak, Margaret N. Park, Susan C. Styer, David Workman
Reconnecting The Sciences, John Eggebrecht, Raymond Dagenais, Don Dosch, Norman J. Merczak, Margaret N. Park, Susan C. Styer, David Workman
Faculty Publications & Research
During the last three years at the Illinois Mathematics and Science Academy, we have been working on a partial reconstruction of Whitehead's "one subject matter," a course reconnecting biology, chemistry, earth and space sciences, and physics into an Integrated Science program.
An Nmr Investigation Of The Effect Of Hydrogen Bonding On The Rates Of Rotation About The C-N Bonds In Urea And Thiourea, Karl A. Haushalter, Janice Lau, John D. Roberts
An Nmr Investigation Of The Effect Of Hydrogen Bonding On The Rates Of Rotation About The C-N Bonds In Urea And Thiourea, Karl A. Haushalter, Janice Lau, John D. Roberts
All HMC Faculty Publications and Research
The interaction between urea and tetrabutylammonium acetate was investigated in dimethylformamide/ dimethyl sulfoxide solutions using ¹H and 15^N NMR. The chemical-shift behavior of the urea protons is consistent with a urea-acetate hydrogen-bonded complex involving both carboxylate oxygens and the urea hydrogens trans to the carbonyl oxygen with K_assoc = 120 ± 10. Line shape analysis of the temperature-dependent ¹H NMR spectra show that ∆G^‡ for rotation about the C-N bond of urea changes only slightly from 11.0 ± 0.1 to 11.2 ± 0.1 kcal/mol on 1:1 molar addition of tetrabutylammonium acetate to a dilute solution of urea. A parallel investigation …
Mile-A-Minute Weed, (Polygonum Perfoliatum L.), An Invasive Vine In Natural And Disturbed Sites, J. Douglas Oliver
Mile-A-Minute Weed, (Polygonum Perfoliatum L.), An Invasive Vine In Natural And Disturbed Sites, J. Douglas Oliver
Faculty Publications and Presentations
Polygonum perfoliatum L. (Polygonaceae) or mile-a-minute weed, from eastern Asia, has been spreading through wild and disturbed areas of the mid-Atlantic United States. It has a wide ecological amplitude and is found on stream banks, moist thickets, roadsides, nurseries, wood-piles, clearings, and ditches. Polygonum perfoliatum presents serious problems for reforestation because it thrives where forests are clear-cut. A southward direction of spread indicates that the species will probably proliferate in at least some southern states. Mechanical control is not likely to be completely effective because seeds are often left behind. No appropriate biocontrols are known. The plant poses a threat …