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A QTL study was performed in large half-sib families to characterize the genetic background of variation in pork quality traits as well as to examine the possibilities of including QTL in a marker-assisted selection scheme. The quality traits included ultimate pH in LM and the semimembranosus, drip loss, and the Minolta color measurements [L.sup.*], [a.sup.*], and [b.sup.*] representing meat lightness, redness, and yellowness, respectively. The families consist of 3,883 progenies of 12 Duroc boars that were evaluated to identify the QTL. The linkage map consists of 462 SNP markers on 18 porcine autosomes. Quantitative trait loci were mapped using a linear mixed model with fixed factors (sire, sex, herd, month, sow age) and random factors (polygenic effect, QTL effects, and litter). Chromosome-wide and genome-wide significance thresholds were determined by Peipho's approach, and 95% Bayes credibility intervals were estimated from a posterior distribution of the QTL position. In total, 31 QTL for the 6 meat quality traits were found to be significant at the 5% chromosome-wide level, among which 11 QTL were significant at the 5% genome-wide level and 5 of these were significant at the 0.1% genome-wide level. Segregation of the identified QTL in different families was also investigated. Most of the identified QTL segregated in 1 or 2 families. For the QTL affecting ultimate pH in LM and semimembranosus and [L.sup.*] and [b.sup.*] value on SSC6, the positions of the QTL and the shapes of the likelihood curves were almost the same. In addition, a strong correlation of the estimated effects of these QTL was found between the 4 traits, indicating that the same genes control these traits. A similar pattern was seen on SSC15 for the QTL affecting ultimate pH in the 2 muscles and drip loss. The results from this study will be helpful for fine mapping and identifying genes affecting meat quality traits, and tightly linked markers may be incorporated into marker-assisted selection programs. Key words: linkage analysis, meat quality, pig, quantitative trait loci doi: 10.2527/jas.2009-2590

The solenoid and double pancake windings are developed for a three-phase 26-kVA High Temperature Superconducting (HTS) transformer. A numerical analysis is developed to predict the DC and AC behavior of the coils based on measurements of short samples and tested coils at 77 K.

A computational study of the multirow interaction mechanisms has been carried out for a one-and-a-half stage (NGV-rotor-stator) transonic turbine. In addition to measurable subharmonic unsteadiness on the rotor blades induced by two fundamental stator passing frequencies, a significant aperiodic ('mistuned') circumferential variation of unsteady forcing magnitude by about three times has been observed in the downstream stator blades. Further parametric studies with various stator blade counts illustrate that the circumferential variation pattern of the unsteady forcing is dictated by the NGV-stator blade count difference, while the local stator forcing magnitude is affected by its circumferential clocking position relative to the upstream NGV blades. The present work suggests that the circumferential clocking together with the choice of blade count should be considered as an aeromechanical design parameter For cases with stator-stator (or rotorrotor) blade counts resulting in a tuned (or nearly tuned) unsteady forcing pattern, the clocking position should be chosen to minimize the unsteady forcing. On the other hand, if the choice of blade counts leads to a significant aerodynamic aperiodicity (mistuning),the clocking-forcing analysis can be used to identify the most vulnerable blade that is subject to the maximum forcing.[DOI: 10.1115/1.1622711]

Computations of unsteady flows due to inlet distortion driven blade vibrations, characterized by long circumferential wavelengths, typically need to be carried out in multi-passage/ whole-annulus domains. In the present work, a single-passage three-dimensional unsteady Navier-Stokes approach has been developed and applied to unsteady flows around vibrating blades of a transonic fan rotor (NASA Rotor-67) with inlet distortions. The phase-shifted periodic condition is applied using a Fourier series based method, 'shape-correction,' which enables a single-passage solution to unsteady flows under influences of multiple disturbances with arbitrary interblade phase angles. The computational study of the transonic fan illustrates that unsteady flow response to an inlet distortion varies greatly depending on its circumferential wavelength. The response to a long wavelength (whole-annulus) distortion is strongly nonlinear with a significant departure of its time-averaged flow from the steady state, while that at a short wavelength (two passages) behaves largely in a linear manner. Nevertheless, unsteady pressures due to blade vibration, though noticeably different under different inlet distortions, show a linear behavior. Thus, the nonlinearity of the flow response to inlet distortion appears to influence the aerodynamic damping predominantly by means of changing the time-averaged flow. Good agreements between single-passage solutions and multi-passage solutions are obtained for all the conditions considered, which clearly demonstrates the validity of the phase-shifted periodicity at a transonic nonlinear distorted flow condition. For the present cases, typical CPU time saving by a factor of 5-10 is achieved by the single-passage solutions. [DOI: 10.1115/1.1450567]

The roles of reaction pressure and vibration in changing the size and morphology of nanoscale aluminum nitride (AlN) crystals have been studied. Direct current arc plasma using a mixture of ammonia and nitrogen was used in synthesizing nanocrystalline AlN powders. Small-angle x-ray scattering, transmission electron microscopy and Fourier transform infrared spectroscopy were used in studying the physical changes. Results show the reaction pressure can be used in controlling the size of the AlN crystals because the crystals have thermal stability surfaces. The crystals also have a Frohlich mode due to the size effect.

An industrial magnetic separator with 0.5 m warm bore, 1 m effective length, 3.5T central field superconducting magnet system, a high gradient reciprocating canister and corresponding slurry and control systems for kaolin clay purification has been constructed. Laboratory tests at different magnetic fields (1-3.5T) and slurry velocities (0.5-3cm/s) have been conducted. The results show the stable operation and the productivity of 3 t/h dry clay powder with 3.5-5 points brightness enhancement.