Comparison of analytical and flight test identified aerodynamic derivatives for a tandem-rotor transport helicopter

Flight tests for verifying an analytical aerodynamic derivative model of a CH-47 helicopter were conducted for low cruise speeds and transition to hover portions of curved, decelerating landing approach trajectories. All testing was performed on a closed loop basis with the stability augmentation system of the helicopter operating, and response data were obtained using both manual and computer generated input maneuvers. The results indicate some differences between the measured response time histories and those predicted by both analytical and flight test identified derivatives. With some exceptions the discrepancies are not severe, and the overall agreement between the measured and computed time histories is reasonably good. No adverse effects attributable to closed loop testing were noted, and the use of computer generated inputs proved to be superior to manual ones

Copper Complexation by Dissolved Organic Matter in arid Soils: A Voltametric Study

A voltammetric method was used to estimate the complexing capacity of water extracts from both desert soils sampled at the root zone of creosote and salt cedar plants, and in soils from interspace or background regions where no vegetative influence was apparent. The copper complexing capacity of water extracts of these desert soils was influenced by contact time and pH. In soils from the root zones of creosote and salt cedar plant, copper complexation capacities at pH 8 were from 5 µM to 60 µM after five min contact periods, while 18 h contact periods yielded copper complexation capacities of 40 µM–80 µM. Soils with no vegetative influence had copper complexing capacities of less the 2 µM. The copper complexing capacities of these soils are well correlated with the concentration of organic carbon in the water extract (r2 = 0.86). The abundance of soluble organic matter in the root zone of desert shrubs has the potential to control the solution speciation of Cu2+. The formation of soluble complexes should also have an important influence on the plant uptake and transport of copper, as well as other heavy metals in the root zones of desert shrubs and beyond

The Close Corporation and the Colorado Lawyer

http://www.heinonline.org/HOL/Page?handle=hein.journals/ucollr39&div=24&collection=journal

The Close Corporation and the Colorado Lawyer

http://www.heinonline.org/HOL/Page?handle=hein.journals/ucollr39&div=24&collection=journal