An analytical basis for assaying buried biological contamination Interim report

Assay techniques for determining biological contamination of spacecraft material

Assessing Patterns in the Conversion of Rural Lands to Residential Use

Land Economics/Use,

Morphometric Variation in Aphelenchus avenae Bastian, 1865 with Varied Nutrition and Time

The effect of varied time, nutritional media, and species of fungus on taxonomic characters (L, a, b1, c, and V) of Aphelenchus avenae was investigated. The effect of these ecological conditions on morphometrics was variable; however, these characters varied significantly with increased time, decreased nutritional media, and species of fungus. The greatest number of morphometric changes occurred with increased time, and the fewest with species of fungus. With changing environmental conditions, “V” values were the most stable character

Morphometric Variation in Aphelenchus avenae Bastian, 1865 with Varied Nutrition and Time

The effect of varied time, nutritional media, and species of fungus on taxonomic characters (L, a, b1, c, and V) of Aphelenchus avenae was investigated. The effect of these ecological conditions on morphometrics was variable; however, these characters varied significantly with increased time, decreased nutritional media, and species of fungus. The greatest number of morphometric changes occurred with increased time, and the fewest with species of fungus. With changing environmental conditions, “V” values were the most stable character

Effect of cooling-hole geometry on aerodynamic performance of a film-cooled turbine vane tested with cold air in a two-dimensional cascade

The effect of the orientation and cooling-hole size on turbine-vane aerodynamic losses was evaluated. The contribution of individual vane regions to the overall effect was also investigated. Test configurations were based upon a representative configuration having 45 spanwise rows of holes spaced about the entire vane profile. Nominal hole diameters of 0.0254 and 0.0356 cm and nominal hole orientations of 35 deg, 45 deg, and 55 deg from the local vane surface and 0 deg, 45 deg, and 90 deg from the main-stream flow direction were investigated. Flow conditions and aerodynamic losses were determined by vane-exit surveys of total pressure, static pressure, and flow angle

Incidence loss for fan turbine rotor blade in two-dimensional cascade

The effect of incidence angle on the aerodynamic performance of a fan turbine rotor blade was investigated experimentally in a two dimensional cascade. The test covered a range of incidence angles from -15 deg to 10 deg and exit ideal critical velocity ratios from 0.75 to 0.95. The principal measurements were blade-surface static pressures and cross-channel survey of exit total pressure, static pressure, and flow angle. Flow adjacent to surfaces was examined using a visualization technique. The results of the investigation include blade-surface velocity distribution and overall kinetic energy loss coefficients for the incidence angles and exit velocity ratios tested. The measured losses are compared with those from a reference core turbine rotor blade and also with two common analytical methods of predicting incidence loss

Identifying capacitive and inductive loss in lumped element superconducting hybrid titanium nitride/aluminum resonators

We present a method to systematically locate and extract capacitive and inductive losses in superconducting resonators at microwave frequencies by use of mixed-material, lumped element devices. In these devices, ultra-low loss titanium nitride was progressively replaced with aluminum in the inter-digitated capacitor and meandered inductor elements. By measuring the power dependent loss at 50 mK as the Al-TiN fraction in each element is increased, we find that at low electric field, i.e. in the single photon limit, the loss is two level system in nature and is correlated with the amount of Al capacitance rather than the Al inductance. In the high electric field limit, the remaining loss is linearly related to the product of the Al area times its inductance and is likely due to quasiparticles generated by stray radiation. At elevated temperature, additional loss is correlated with the amount of Al in the inductance, with a power independent TiN-Al interface loss term that exponentially decreases as the temperature is reduced. The TiN-Al interface loss is vanishingly small at the 50 mK base temperature.Comment: 10 pages, 5 figure

BOILING HEAT TRANSFER TO LIQUID HYDROGEN AND NITROGEN IN FORCED FLOW

Boiling heat transfer to liquid hydrogen and nitrogen in forced flo

A review of quasi-coherent structures in a numerically simulated turbulent boundary layer

Preliminary results of a comprehensive study of the structural aspects of a numerically simulated number turbulent boundary layer are presented. A direct Navier-Stokes simulation of a flat-plate, zero pressure gradient boundary layer at Re0 = 670 was used. Most of the known nonrandom, coherent features of turbulent boundary layers are confirmed in the simulation, and several new aspects of their spatial character are reported. The spatial relationships between many of the various structures are described, forming the basis for a more complete kinematical picture of boundary layer physics than has been previously known. In particular, the importance of vortex structures of various forms to the generation of Reynolds shear stress is investigated