Structure and ac properties of electron-beam evaporated zirconia thin films

The structure and ac properties of ZrO₂ thin film capacitors were studied as a function of deposition temperature. Zirconia films deposited on molybdenum electrodes were polycrystalline. The monoclinic phase was the major phase detected in the films deposited at temperatures between 300—600 °C. At lower deposition temperatures (190–200 °C), the cubic phase was the major crystalline phase formed. A major (111&#x0304;) and a minor (111) fiber axis were observed for the monoclinic phase. Average crystallite size increased from 118 to 484 Å for the (111&#x0304;) and 175 to 265 Å for the (111) crystallites as deposition temperature increased from 200 to 600 °C. Ac conduction in Mo-ZrO₂-Mo structures at fields < 0.05 MV/cm was dominated by electron hop with a frequency independent loss behavior between 25 and 150 °C. Between 150 and 325 °C, a σ_d ∝ f^y dependence was observed where y depended on measurement and deposition temperatures. The remanence of interfacial polarization was suggested as an additional loss mechanism in this temperature range and for frequencies of 60-10⁵ Hz.     

A genomic map of infectious laryngotracheitis virus and the sequence and organization of genes present in the unique short and flanking regions

The involvement of the intermediate area and B?tzinger complex (BOT) of the rostral ventral respiratory group (r-VRG) in laryngeal control and generation of the expiration reflex were studied in anaesthetized non-paralyzed cats Focal cooling (to 20 degrees C) of the nucleus paraambigualis (NPA) caused changes in the frequency and timing of breathing with the concomitant rise in laryngeal resistance. Cooling of the nucleus ambiguus resulted in a consistent drop in laryngeal resistance. Alterations in timing and intensity of breathing but no changes in laryngeal patency were found during cooling of the BOT. The expiration reflex was inhibited by cooling of either the NPA or BOT. The role of these medullary regions in the control of laryngeal patency and central integration of the expiration reflex is discussed.     

Comment on "Articulation of values."

This article clarifies several research issues raised in a recent article by Krieshok, Arnold, Kuperman, and Schmitz concerned with repertory grid methodology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Impact of agriculture on soil consumption of atmospheric CH4 and a comparison of CH4 and N2O flux in subarctic, temperate and tropical grasslands

Increasing concentrations of methane (CH₄) in the atmosphere are projected to account for about 25% of the net radiative forcing. Biospheric emissions of CH₄ to the atmosphere total approximately 400 Tg C y^-1. An estimated 300 Tg of CH₄-C y^-1 is oxidized in the atmosphere by hydroxyl radicals while about 40 Tg y^-1 remains in the atmosphere. Approximately 40 Tg y^-1 of the atmospheric burden is oxidized in aerobic soils. Research efforts during the past several years have focused on quantifying CH₄ sources while relatively less effort has been directed toward quantifying and understanding the soil sink for atmospheric CH₄. Recent research has demonstrated that land use change, including agricultural use of native forest and grassland systems has decreased the soil sink for atmospheric methane. Some agricultural systems consume atmospheric CH₄ at rates less than 10% of those found in comparable undisturbed soils. While it has been necessary to change land use practices over the past centuries to meet the required production of food and fiber, we need to recognize and account for impacts of land use change on the biogeochemical nutrient cycles in the biosphere. Changes that have ensued in these cycles have and will impact the atmospheric concentrations of CH₄ and N₂O. Since CH₄ and N₂O production and consumption are accomplished by a variety of soil microorganisms, the influence of changing agricultural, forest, and, demographic patterns has been large. Existing management and technological practices may already exist to limit the effect of land use change and agriculture on trace gas fluxes. It is therefore important to understand how management and land use affect trace gas fluxes and to observe the effect of new technology on them. This paper describes the role of aerobic soils in the global CH₄ budget and the impact of agriculture on this soil CH₄ sink. Examples from field studies made across subarctic, temperate and tropical climate gradients in grasslands are used to demonstrate the influence of nutrient cycle perturbations on the soil consumption of atmospheric CH₄ and in increased N₂O emissions. This revised version was published online in August 2006 with corrections to the Cover Date.     

Soil removal as a rate process

The rate of soil removal during multiple cycle washing has been studied for three artificially soiled cotton test cloths. Results are considered in relation to a soil removal rate concept proposed some years ago by Vaughn, Vittone, and Smith. It is shown that the rate of removal for these soils, when washed in the Terg-O-Tometer with a built, anionic, synthetic detergent, does not correspond to a simple first order rate process as proposed by Vaughn et al. Rather, it was found that under a variety of washing situations the percentage soil removal increased linearly with the log of cumulative wash time. Further, it was shown that for those experiments involving detergent concentration or level of mechanical action, the slopes of these log time relationships, which reflect the rate of soil removal, vary in the expected manner.     

The normal of a fractal surface

  We have discovered a class of fractal functions that are differentiable. Fractal interpolation functions have been used for over a decade to generate rough functions passing through a set of given points. The integral of a fractal interpolation function remains a fractal interpolation function, and this new fractal interpolation function is differentiable. Tensor products of pairs of these fractal functions form fractal surfaces with a well-defined tangent plane. We use this surface normal to shade fractal surfaces, and demonstrate its use with renderings of fractal mirrors.     

Construct systems and the definition of social situations.

Studied the relationship between 2 construct subsystems, one for construing people and one for defining a concrete social situation. Using a variant of G. Kelly's grid methodology, 20 college students rated 12 personal acquaintances on 12 constructs of bipolar concepts. They were then presented with 1 of 2 problematic social situations and asked to rate the same acquaintances on 10 dimensions relevant to the situation. Principal-components analysis was used to derive 1 central and 2 secondary patterns of construing (centrality being defined by the amount of variance the component accounts for on a grid), as well as 1 central and 2 secondary dimensions defining the social situation. Cross-correlations between the orderings of people on these 2 sets of components were used to determine the extent to which "implicit personality theory" influenced the definition of a situation. Findings show that central construing related strongly to the central definition of a situation, whereas secondary construing related more weakly to secondary definitions. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dynamic dispatching rule-pairs for multitasking workers in JIT production systems

The concept of multitasking workers plays a major role in the success of Just-inTime (JIT) implementation. One key element of a JIT system is its ability to use multitasking workers to react to unbalanced workloads where the bottleneck location changes from period to period. In addition to existing rule-pairs (when to move and where to move), this study develops eight new dynamic dispatching rule-pairs especially for assigning multitasking workers within a JIT production environment. The purpose of this study is to evaluate the performance of these rule-pairs using object-oriented discrete-event simulation and response surface methodology.