Pressure and velocity measurements in a three-dimensional wall jet

The effects on the flow fields of varying the ratio of the velocity at the exit plane of the nozzle to the outer tunnel flow are reported. The pressure-velocity correlations are taken and some trends are discussed. Emphasis is placed on comparing the coherence between the fluctuating pressure and velocity fields at various locations in the different flow configurations

An experimental investigation of an axisymmetric jet in a coflowing airstream

The flow development of an axisymmetric jet exhausting into a moving airstream has been studied. The jet has a Reynolds number of 22,600, and the ratio of the jet velocity to the wind tunnel velocity is 5.1 to 1. The flow field of the axisymmetric jet was examined at locations varying from approximately zero to eight diameters downstream of the orifice. Of primary concern at each downstream location was the mapping of the one point statistical properties of the flow, including mean velocity, turbulent intensity, and intermittency. Autocorrelations and power spectral density curves were determined for both the fluctuating velocity field and the concentration signal at various distances from the jet's center line for different downstream locations. A laser Doppler velocimeter, using a phase locked loop processor, was used to make the desired velocity field measurements which were compared with hot wire anemometer and pressure probe data

Investigations of scaling laws for jet impingement

The statistical properties of tangential flows over surfaces were investigated by two techniques. In one, a laser-Doppler velocimeter was used in a smoke-laden jet to measure one-point statistical properties, including mean velocities, turbulent intensities, intermittencies, autocorrelations, and power spectral densities. In the other technique, free stream and surface pressure probes connected to 1/8 inch microphones were used to obtain single point rms and 1/3 octave pressures, as well as two point cross correlations, the latter being converted to auto spectra, amplitude ratios, phase lags, and coherences. The results of these studies support the vortex model of jets, give some insights into the effects of surface impingement, and confirm that jet diameter and velocity are the scaling parameters for circular jets, while Reynolds number is relatively unimportant

Review of the literature on individual education plans

Aims and Scope of the Review - this review was carried out under a contract with the New Zealand Ministry of Education, which contained the following requirements: A literature review of national and international developments in the use of the Individual Education Plan (IEP) with schools and families, with particular attention to special education assessment practice(s) and their relationship to the IEP process. The purposes of the review were defined as follows: 1. To undertake a literature review of national and international developments in IEP processes and special education assessment practice to contribute to the Ministry of Education’s current project to review, revise and position the Individual Education Programme (IEP) Guidelines in relation to: the New Zealand Curriculum (Ministry of Education 2007), current assessment practices, effective teaching and learning practices, and engagement and reporting to parents, family and whanau (National Standards). 2. To provide both New Zealand and international research evidence of effective and/or evidence based practice, which, along with the data being collected by the Ministry of Education project team, will ultimately inform the future use of IEPs. The scope of the review was defined as follows: 1. The focus of the review is to be on: students with special needs in all school sector settings, students as learners, not the disability or the diagnosis they present with, the use of IEPs with schools and parents, the role of special education staff and other agencies in the IEP process, and what makes the IEP process effective for schools, students and their families, and what evidence there is of their effectiveness, with particular reference to the educational implications. 2. The literature sourced will include studies from both New Zealand and overseas, and peer reviewed journals and other publications

Quantum computing with an electron spin ensemble

We propose to encode a register of quantum bits in different collective electron spin wave excitations in a solid medium. Coupling to spins is enabled by locating them in the vicinity of a superconducting transmission line cavity, and making use of their strong collective coupling to the quantized radiation field. The transformation between different spin waves is achieved by applying gradient magnetic fields across the sample, while a Cooper Pair Box, resonant with the cavity field, may be used to carry out one- and two-qubit gate operations.Comment: Several small corrections and modifications. This version is identical to the version published in Phys. Rev. Let

Electron spin relaxation of N@C60 in CS2

We examine the temperature dependence of the relaxation times of the molecules N@C60 and N@C70 (which comprise atomic nitrogen trapped within a carbon cage) in liquid CS2 solution. The results are inconsistent with the fluctuating zero field splitting (ZFS) mechanism, which is commonly invoked to explain electron spin relaxation for S > 1/2 spins in liquid solution, and is the mechanism postulated in the literature for these systems. Instead, we find a clear Arrhenius temperature dependence for N@C60, indicating the spin relaxation is driven primarily by an Orbach process. For the asymmetric N@C70 molecule, which has a permanent non-zero ZFS, we resolve an additional relaxation mechanism caused by the rapid reorientation of its ZFS. We also report the longest coherence time (T2) ever observed for a molecular electron spin, being 0.25 ms at 170K.Comment: 6 pages, 6 figures V2: Updated to published versio

Male Flat Jockeys Do Not Display Deteriorations in Bone Density or Resting Metabolic Rate in Accordance With Race Riding Experience: Implications for RED-S.

Despite consistent reports of poor bone health in male jockeys, it is not yet known if this is a consequence of low energy availability or lack of an osteogenic stimulus. Given the rationale that low energy availability is a contributing factor in low bone health, we tested the hypothesis that both hip and lumbar bone mineral density (BMD) should progressively worsen in accordance with the years of riding. In a cross-sectional design, male apprentice (n=17) and senior (n=14) jockeys (matched for body mass and fat free mass) were assessed for hip and lumbar spine BMD as well as both measured and predicted resting metabolic rate (RMR). Despite differences (P0.05) in hip (-0.9 ± 1.1 v -0.8 ± 0.7) and lumbar Z-scores (-1.3 ± 1.4 v -1.5 ± 1) or measured RMR (1459 ± 160 v 1500 ± 165 kcal.d-1) between apprentices and senior jockeys, respectively. Additionally, years of race riding did not demonstrate any significant correlations (P>0.05) with either hip or lumbar spine BMD. Measured RMR was also not different (P>0.05) from predicted RMR in either apprentice (1520 ± 44 kcal.d-1) or senior jockeys (1505 ± 70 kcal.d-1). When considered with previously published data examining under-reporting of energy intake and direct assessments of energy expenditure, we suggest that low BMD in jockeys is not due to low energy availability per se, but rather, the lack of an osteogenic stimulus associated with riding

Switchable ErSc2N rotor within a C80 fullerene cage: An EPR and photoluminescence excitation study

Systems exhibiting both spin and orbital degrees of freedom, of which Er3+ is one, can offer mechanisms for manipulating and measuring spin states via optical excitations. Motivated by the possibility of observing photoluminescence and electron paramagnetic resonance from the same species located within a fullerene molecule, we initiated an EPR study of Er3+ in ErSc2N@C80. Two orientations of the ErSc2N rotor within the C80 fullerene are observed in EPR, consistent with earlier studies using photoluminescence excitation (PLE) spectroscopy. For some crystal field orientations, electron spin relaxation is driven by an Orbach process via the first excited electronic state of the 4I_15/2 multiplet. We observe a change in the relative populations of the two ErSc2N configurations upon the application of 532 nm illuminations, and are thus able to switch the majority cage symmetry. This photoisomerisation, observable by both EPR and PLE, is metastable, lasting many hours at 20 K.Comment: 4 pages, 4 figure