Technique for improving hydrodynamic gyro bearings

Conical or spherical, spirally grooved grease bearings have an inclined surface which is machined inboard of the grooved surface. The indentation and inclined surface provide a reservoir for forced out lubricant, and when rotation begins, centrifugal force returns the lubricant to the grooved area

Increasing Knowledge by Leaps and Bounds: Using Experiential Learning to Address Threshold Concepts

The discussion of threshold concepts is growing in the management education literature. These concepts create challenges for students and instructors since they act as barriers to learning. The reward for overcoming these obstacles is the opening of new ways of thinking that were not available before the student mastered the threshold concepts. We propose in this article that many students believe business education is “common sense” and do not understand that management is practice informed by theory. When students master the threshold concept concerning the “underlying game” of management, they begin to develop deeper and more meaningful understandings. From this perspective we demonstrate how we have used experiential exercises in an operations management class to facilitate active, social, and creative learning that exposes this threshold concept and moves the student through the preliminal, liminal, and postliminal stages of threshold concept mastery

UK devolution and the European Union: a tale of cooperative asymmetry?

The post 1999 devolution project has resulted in a major recalibration of the pre-existing arrangements for making European Union policy within the UK. The devolved administrations in Scotland and Wales (but not the English regions) have gained in electoral legitimacy and legislative powers, and thereby a greater claim to consultation with UK central government. Four key characteristics of EU policy making in a devolved UK are identified. The legal contingency of the 'devolveds'' status has not yet impeded traditional cooperative relations between government tiers, but the stability of the new arrangements remains in question. The UK case is compared to EU regionalisation in other member states and a distinction is drawn between a cooperative regionalist approach (the devolveds) and a consultative one (the English regions)

Seedhead Suppression in Tall Fescue with Chaparral Herbicide

Tall Fescue (Lolium arundinaceum (Schreb.)) is cool-season perennial grass found in pastures throughout the Eastern US, most commonly in the transition zone. It’s tolerance to extreme temperatures, drought, poor soil fertility, heavy grazing, and pests have made it a reliable forage base for livestock pastures. Released in 1943, ‘KY-31’ tall fescue was quickly adopted by cattle producers and now inhabits an estimated 40 million acres in the US. Soon after its adoption, cattle producers began to notice a reduction in animal performance and signs that animals were heat stressed following tall fescue consumption. These symptoms were an indication of an animal disorder that would later be called “fescue toxicosis” by scientists and producers. In the late 1970s, it was discovered that the cattle health issues with tall fescue were actually caused by a fungus (Neotyphodium coenophialum) living within some plants, which produced a toxic class of compounds termed ergot alkaloids. We refer to these tall fescue plants that contain this fungus as being endophyte infected (E+) and those that do not as being endophyte free (E-)

Dynamic phenomena in superconducting oxides by ESR

Dynamic electron spin resonance (ESR) measurements compare the paramagnetic and antiferromagnetic (AF) properties of superconducting oxides in the range 4 K to room temperature, at 8 MHz and 9.36 GHz. Two are derivatives of YBa2Cu30 7: 1: Nd(Nd0.05Ba0.95 )2Cu30 7, Te0 =72 K and II: Y0.2Cao.8Sr2[Cu2(Tlo.5Pb0.5 )]07, Te0 =108 K and two are cases where AF ordering dominates the weak superconductivity: III: Nb01.1\u3e 1. 25 ~Teo~ 10 K and IV: La2Ni04.00, 70 K :::: Teo:::: 40 K. At temperatures 298:::: T:::: 64 K, the ESR absorption by I indicates orthorhombic symmetry. The peaks at Ke =2.06, gb =2.13, and Ka =2.24 are identified with the presence of 5% Nd3+( 41912 ) in the Ba layer because the characteristic Cu2+ impurity hyperfine structure is absent and the ESR signal disappears several degrees below Te. Near Te the ESR absorption is reduced by two orders of magnitude. Proximity effects give rise to interference fringes with period r1 ( T) independent of the field B and the rate of sweep dBzldt. ESR is observed below Te because flux penetrates the superconductor. The temperature dependence of r1 leads to an activation energy for the flux motion E0 (1)/R ~ 16 K and Ea (111)/R ~3 K =Te /4. In the superconducting state a coherent flux expulsion response to a change in B. from 500 mT to zero is observed in times T, = 8 to 10 s. The inverse rate of noise spikes due to flux expulsion, when the samples are cooled through Te in a magnetic field, varies from Tnoise=3.5 s for III to 21 s for IV. The microwave absorption spectra identify three temperature regimes: (i) For 3.5 K \u3c T \u3c T m T* \u3c Teo superconducting behavior was confirmed by the energy loss near zero magnetic field and the kinetics of high-field noise due to flux expulsion. Near g =2.00 ESR absorption is observed for all materials. A broad absorption near 50 to 100 mT at 9.36 GHz has been attributed to AF resonance. (ii) T m T* ~ T ~ Te identifies the range where flux motion gives rise to interference fringes in the ESR absorption. (iii) ESR and AF resonance are observed immediately after warming above Tc