Gas Chromatography Techniques for the Determination of Dilute Constituents of Biological Material, Including Consideration of Material Relevant to the Ecology of Astronauts Status Report, Oct. 6, 1965 - Apr. 6, 1966

Mass spectrometer techniques for analyzing dilute constituents of mitochondrial suspensio

Temperature and Isotope Dependent Kinetics of Nickel-Catalyzed Oxidation of Methane by Ozone

The temperature dependent kinetics of Ni+ + O3 and of NiO+ + CH4/CD4 are measured from 300 to 600 K using a selected-ion flow tube apparatus. Together, these reactions comprise a catalytic cycle converting CH4 to CH3OH. The reaction of Ni+ + O3 proceeds at the collisional limit, faster than previously reported at 300 K. The NiO+ product reacts further with O3, also at the collisional limit, yielding both higher oxides (up to NiO5+ is observed) as well as undergoing an apparent reduction back to Ni+. This apparent reduction channel is due to the oxidation channel yielding NiO2+∗ with sufficient energy to dissociate. 4NiO+ + CH4 (CD4) (whereas 4NiO+ refers to the quartet state of NiO+) proceeds with a rate constant of (2.6 ± 0.4) × 10-10 cm3 s-1 [(1.8 ± 0.5) × 10-10 cm3 s-1] at 300 K and a temperature dependence of ∼T-0.7±0.3 (∼T-1.1±0.4), producing only the 2Ni+ + 1CH3OH channel up to 600 K. Statistical modeling of the reaction based on calculated stationary points along the reaction coordinate reproduces the experimental rate constant as a function of temperature but underpredicts the kinetic isotope shift. The modeling was found to better represent the data when the crossing from quartet to doublet surface was incomplete, suggesting a possible kinetic effect in crossing from quartet to doublet surfaces. Additionally, the modeling predicts a competing 3NiOH+ + 2CH3 channel to become increasingly important at higher temperatures

Systematic landscape restoration in the rural-urban fringe: meeting conservation planning and policy goals

The original publication is available at www.springerlink.comMany landscapes that straddle the rural/urban divide suffer from low levels of species diversity following extensive clearing and fragmentation of native vegetation communities and conversion of land to agriculture. Further pressures are placed on remnant vegetation by encroaching urban expansion. These landscapes now exhibit a mosaic of small, patchy vegetation remnants that are under considerable pressure from housing and light-industrial development. Furthermore, agriculture in these landscapes tends to be of high economic value from uses such as intensive horticulture. Concerted and well-planned efforts are needed to balance the many conflicts of interest and competing demands for land with the need to restore landscapes for the protection of biodiversity. There has been a recent move in Australia toward regional biodiversity planning and goal setting, however specific detail on how to plan for achieving targets in complex landscapes is lacking. This paper applies a systematic landscape restoration model to a mixed-use, peri-urban landscape on the northern fringes of Adelaide, South Australia. The region contains fragments of remnant vegetation amongst a mosaic of high-value horticulture, light industry and urban development. Models produce maximally efficient solutions that meet comprehensive, adequate and representative conservation targets. Further constraints are added to the model to take into account the value of agricultural output, the biodiversity value of remnants, and property size and tenure. The effects on solution efficiencies as the number of constraints increase are investigated. This paper demonstrates the flexibility found in applying a systematic landscape restoration methodology. The process we present can be transferred to any rural-urban fringe region. © 2007 Springer Science+Business Media, Inc.Neville D. Crossman, Brett A. Bryan, Bertram Ostendorf and Sally Collin