The American Upper Ordovician Standard. VI, The Covington Sequence at Maysville, Kentucky

Author Institution: Department of Geology, The Ohio State University, Columbus 1

Comparison of straight and 15 degree vectored nozzles using a six component thrust stand

This project compared the forces and moments produced by straight and 15 degree vectored nozzles. Using the six component thrust stand in the engines laboratory at California Polytechnic State University, several trials were performed. This data was then reduced using first a computer program and then later an electronic spreadsheet. This reduced data was graphed and compared. As a result of these comparisons some unexpected forces were discovered. Several more tests were run including a zero thrust test and a statistical comparison were done to discover the source of these discrepancies. As a direct result several nozzle changes were made and significant revisions to the thrust stand are being made

Expansion of New Law in Southeast May Stave Off Black Land Loss

Landownership and homeownership are significant contributors to the creation of wealth and thus, drivers of intergenerational economic mobility. However, many people who have inherited family land are unable to realize these opportunities because of the legal effect of their particular form of landownership, often called heirs\u27 property. These landowners are more likely to lose their land through what is known as a partition sale—a property sale resulting from a dispute between co-owners, often ignited by an outside party with an investment interest in the land. This Partners Update article explores the repercussions of heirs\u27 property ownership and examines legislative solutions recently enacted in three southeastern states: Florida, Mississippi, and Virginia

The Literary Theory of Ayn Rand

The author believes that Ayn Rand presents a systematic approach to aesthetics and that her work presents an interesting and significant approach to aesthetic problems. The author will attempt to present Ayn Rand's basic aesthetic concepts that throw light on her literary theory. The author will also present her views on literary schools and of individual authors

Evaluation of dual flow thrust vector nozzles with exhaust stream impingement

To supplement previous work performed by NASA, a cold-jet facility was established at the California Polytechnic State University, San Luis Obispo campus. The purpose of this facility is to continue the studies of cold flow multiaxis thrust vectoring conducted at the NASA Langley Research Center. A single nozzle test apparatus was completed and is presently operational. Included are the results of the single flow test envelope that was requested by NASA personnel. Details about the test apparatus are included in the Cal Poly Semi-Annual Progress report

Effects of wall compliance on the laminar–turbulent transition of torsional Couette flow

Torsional Couette flow between a rotating disk and a stationary wall is studied experimentally. The surface of the disk is either rigid or covered with a compliant coating. The influence of wall compliance on characteristic flow instabilities and on the laminar–turbulent flow transition is investigated. Data obtained from analysing flow visualizations are discussed. It is found that wall compliance favours two of the three characteristic wave patterns associated with the transition process and broadens the parameter regime in which these patterns are observed. The results for the effects of wall compliance on the third pattern are inconclusive. However, the experiments indicate that the third pattern is not a primary constituent of the laminar–turbulent transition process of torsional Couette flow

Design and evaluation of single and dual flow thrust vector nozzles with post exit vanes

This Thrust Vectored Research project required that a 1/24 scale model of the F/A-18 High Alpha Research Vehicle, (HARV), propulsion system be constructed on the university campus. This propulsion system was designed for cold flow testing on a multicomponent test rig. Forces and moments were measured to study nozzle performance parameters. The flow visualization technique of color Schlieren photography was performed to investigate the flow phenomena at the nozzle exit. The flow interactions that were identified consisted of vane nozzleing between the outer and lower vanes and vane tip interference. The thrust vectoring system consisted of three asymmetrically spaced vanes installed circumferentially on a maximum afterburner nozzle. The performance of the nozzle was investigated with the outer and lower vanes equally deflected, (-10 deg is less than delta(sub v) is less than 25 deg), and with the upper vane fully retracted, (delta(sub v) equals -10 deg). The nozzle pressure ratio ranged from 4 to 6. The results indicated that a vane nozzleing effect developed at nozzle pressure ratios of 4 and 6 when the outer and lower vanes were deflected far enough into the flow field such that the increase in vane area accelerated the flow past the vanes causing distorted shock waves. This accelerated flow was a result of a pressure differential existing between the inside surface of the vane and the ambient pressure. The stagnation pressure that developed along the inside surface of the vane accelerated the flow past the vanes causing it to equalize with ambient pressure, thus providing distorted shock waves. A tip interference was present at the trailing edge of the upper vane as a result of low nozzle pressure, NPR 4, with high vane deflection, delta(sub v) equals 25 degrees, and also with a high nozzle pressure, NPR 6, and low vane deflections, delta(sub v) equals 15 degrees

Laminar-turbulent boundary-layer transition over a rough rotating disk

Boundary-layer transition over a disk spinning under water is investigated. Transitional Reynolds numbers, Re-c, and associated boundary-layer velocity profiles are determined from flow-visualizations and hot-film measurements, respectively. The value of Re-c and the velocity profiles are studied as a function of the disk's surface roughness. It is found that transition over rough disks occurs in a similar fashion to that over smooth disks, i.e., abruptly and axisymmetrically at well-defined radii. Wall roughness has little effect on Re-c until a threshold relative roughness is reached. Above the threshold Re-c decreases sharply. The decrease is consistent with the drop one expects for our flow for the absolute instability discovered by Lingwood [J. Fluid Mech. 299, 17 (1995); 314, 373 (1996); 331, 405 (1997)]. This indicates that the Lingwood absolute instability may continue to play a major role in the transition process even for large relative roughness. (C) 2003 American Institute of Physics

Voluntary Wheel Running during Weight Loss Leads to Differential Changes in Monocytes, Compared to Forced Treadmill Running

High-fat feeding and subsequent weight gain may contribute to innate immune dysfunction. Weight loss via calorie restriction and exercise represent one means to restore normal immune function. The purpose of the study was to examine how 8- weeks of aerobic exercise and low-fat diet affects weight gain, monocyte concentration, and monocyte cell-surface expression of TLR2, TLR4, CD80, and CD86. For 12- months, 24 male CD-1 mice underwent a pre-treatment phase, consuming either a low fat (10% fat) or high-fat (60% fat) diet ad libitum. Mice were randomly assigned to one of four groups (N=6/group): CN (low-fat sedentary), V-EX (voluntary wheel running), F10 EX (forced treadmill running), or SD (sedentary). V-EX, F-EX, and SD groups were switched from the high-fat to low-fat diet for an 8-week treatment period, while the CN group continued consuming the low-fat diet. Saphenous vein blood samples were analyzed using flow cytometry at baseline, week 4, and week 8. V-EX (36.4%) and F14 EX (27.1%) lost significant body weight over 8-weeks (P\u3c0.001). V-EX ran 4.4x more than F-EX (P\u3c0.001). As a group, V-EX had higher monocyte concentration than CN (48.9%) and F-EX (58.9%, P=0.004). Cell-surface expression of TLR2 (22.9%, P=0.002), TLR4 (33.3%, P\u3c0.001), and CD86 (18.6%, P\u3c0.001) increased from baseline to week 8. A time effect was seen in week 4 when CD80 expression was 42% greater for V-EX than SD (P=0.013). The present study confirms short-term exercise and low-fat diet consumption cause significant weight loss and altered immune profile as measured by increased TLR2, TLR4, CD80, and CD86 expression

High Power ECR Ion Thruster Discharge Characterization

Electron cyclotron resonance (ECR) based ion thrusters with carbon based ion optics can potentially satisfy lifetime requirements for long duration missions (approximately 10 years) because grid erosion and cathode insert depletion issues are virtually eliminated. Though the ECR plasma discharge has been found to typically operate at slightly higher discharge losses than conventional DC ion thrusters (for high total thruster power applications), the discharge power fraction is small (less than 1 percent at 25 kW). In this regard, the benefits of increased life, low discharge plasma potentials, and reduced complexity are welcome tradeoffs for the associated discharge efficiency decrease. Presented here are results from discharge characterization of a large area ECR plasma source for gridded ion thruster applications. These measurements included load matching efficacy, bulk plasma properties via Langmuir probe, and plasma uniformity as measured using current probes distributed at the exit plane. A high degree of plasma uniformity was observed (flatness greater than 0.9). Additionally, charge state composition was qualitatively evaluated using emission spectroscopy. Plasma induced emission was dominated by xenon ion lines. No doubly charged xenon ions were detected