https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:49792 Wed 31 May 2023 15:03:39 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:42630 Wed 31 Aug 2022 09:04:14 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:34227 λ). For example, in the region below about 0.2δ (δ is the boundary layer thickness) where Re_λ varies significantly, S and F strongly vary with Re_λ and can be multivalued at a given Re_λ. In the outer region, between 0.3δ and 0.6δ, S, F, and Re_λ remain approximately constant. The channel flow direct numerical simulation data for S and F exhibit a similar behavior. These results point to the ambiguity that can arise when assessing the Re_λ dependence of S and F in wall shear flows. In particular, the multivaluedness of S and F can lead to erroneous conclusions if y/δ is known only poorly, as is the case for the atmospheric shear layer (ASL). If the laboratory turbulent boundary layer is considered an adequate surrogate to the neutral ASL, then the behavior of S and F in the ASL is expected to be similar to that reported here.]]> Wed 20 Feb 2019 15:55:38 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:3147 Wed 11 Apr 2018 17:15:24 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:16628 Wed 11 Apr 2018 17:15:19 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:3334 Wed 11 Apr 2018 17:07:46 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:2972 Wed 11 Apr 2018 17:06:32 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:17014 Wed 11 Apr 2018 16:51:15 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:3458 n, the intermittency exponents µα based on individual and mixed sixth-order structure functions, the scaling exponents ζα(n) of the locally averaged energy and temperature dissipation rates approximated by (δα/δx)2, the flatness factors of the derivatives δα/δx, and the probability density functions (PDFs) of δα/δx, the increment δα and (δα/δx)2. It is found that v and θ are similar in terms of their intermittency characteristics. They are more intermittent than u. The scaling exponent ζv(n) is marginally larger than ζθ(n). The intermittency exponent µθ is smaller than µv based on the estimate of mixed sixth-order structure functions, while µθ is nearly equal to µv based on the estimate of individual sixth-order structure functions. The temperature dissipation rate is more intermittent than the turbulent energy dissipation rate, as indicated by τα(n). The flatness factor of δθ/δx is marginally larger than that of δv/δx. The PDFs of δθ/δx, deltaθ, and (δθ/δx)2 show the strongest departure from the Gaussian distribution.]]> Wed 11 Apr 2018 15:53:37 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:28624 Pm̅3m →(T_c₃ = 185 K) → phase II, I4/mcm →(T_c₂ =T_N = 87 K) → phase III, antiferromagnetic, Cmcm → (T_c₃ = 82 K) → phase IV, canted ferromagnet, Pnma. It is concluded that observed changes in the elastic properties can be explained simply in terms of strain/order parameter coupling for the octahedral tilting transitions. There appears to be no evidence in the present data or in data from the literature for coupling between the magnetic order parameter and shear strains. Any coupling between the magnetic and structural transitions is therefore weak, probably occurring only biquadratically through a small common volume strain. The combined data show unambiguously that, for the crystal used, the Néel point and the structural transition at 87 K are coincident. In other crystals, with slightly different stoichiometries and defect contents, this need not be the case, however, and the overlap of transition temperatures in KMnF₃ is essentially accidental. Strong acoustic dissipation at ∼0.1–1 MHz in the stability field of phase II is attributed to the local mobility of transformation twin walls under externally applied stress. A Debye-like loss peak near 130 K is attributed to pinning of at least some twin walls by defects, but relatively high levels of acoustic dissipation below this freezing temperature imply that some of the twin walls remain mobile due to weak pinning or the absence of any pinning. Acoustic losses continue in the stability field of phase III (Cmcm) but diminish substantially in the stability field of phase IV (Pnma), implying quite different twin mobilities in the different structure types. Overlap of the structural and magnetic instabilities in KMnF₃ opens up possibilities for manipulation of ferroelastic twinning by application of a magnetic field and for creation of materials in which the ferroelastic twin walls have quite different magnetic properties from the matrix in which they lie.]]> Wed 11 Apr 2018 15:47:04 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:3139 Wed 11 Apr 2018 15:35:31 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:3278 Wed 11 Apr 2018 15:14:19 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:3508 Wed 11 Apr 2018 15:06:23 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:17033 t which exhibits some remarkable universal facets over an impressively wide range of scales. This allows us to model the third-order structure functions in different decaying flows covering a large extent of Reynolds numbers. The model is numerically time integrated to predict the decay of second-order structure functions and compared to experiments in grid turbulence. Agreement between predictions and measurements is satisfactory.]]> Wed 11 Apr 2018 14:57:04 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:20227 Wed 11 Apr 2018 14:55:27 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:3289 Wed 11 Apr 2018 14:50:27 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:4409 Wed 11 Apr 2018 14:19:48 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:13600 Wed 11 Apr 2018 13:56:16 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:3295 Wed 11 Apr 2018 13:51:44 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:4411 Wed 11 Apr 2018 13:50:50 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:17751 Wed 11 Apr 2018 13:47:33 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:1926 Wed 11 Apr 2018 13:35:59 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:2831 Wed 11 Apr 2018 13:18:46 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:4412 Wed 11 Apr 2018 13:10:46 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:601 Wed 11 Apr 2018 13:01:22 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:14334 *, well below the conventional Burns temperature but ~50 K above the ferroelectric transition. Elastic softening due to polarization of the PNR shows polarization memory through two phase transitions and is greater than the softening associated with polarization of the ferroelectric phases. This emphasizes that PNR dominate the material properties at all temperatures below T^*.]]> Wed 11 Apr 2018 12:59:09 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:3303 Wed 11 Apr 2018 12:57:43 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:3131 Wed 11 Apr 2018 12:39:22 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:576 Wed 11 Apr 2018 12:31:49 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:3507 Wed 11 Apr 2018 11:36:02 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:1703 Wed 11 Apr 2018 11:22:36 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:16627 Wed 11 Apr 2018 10:47:43 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:3287 Wed 11 Apr 2018 10:05:53 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:4410 Wed 11 Apr 2018 09:23:49 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:2482 Wed 11 Apr 2018 09:23:35 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:7371 Wed 11 Apr 2018 09:17:40 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:31949 Wed 08 Jul 2020 12:31:16 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:34388 1/4] and velocity scale v_K [≡(ν⋶)^1/4] also emerge as natural scaling parameters in conformity with SP, indicating that Kolmogorov's first hypothesis is subsumed under the more general hypothesis of SP. Further, the requirement for a very large Reynolds number is also relaxed, at least for the first similarity hypothesis. This requirement however is still necessary to derive the two-thirds law (or the four-fifths law) from the analysis. These analytical results are supported by experimental data in wake, jet, and grid turbulence. An expression for the fourth-order moment of the longitudinal velocity increments (δu)⁴ is derived from the analysis carried out in the inertial range. The expression, which involves the product of (δu)² and ∂δp/∂x, does not require the use the volume-averaged dissipation ⋶_r, introduced by Oboukhov [Oboukhov, Some specific features of atmospheric turbulence, J. Fluid Mech. 13, 77 (1962)] on a phenomenological basis and used by Kolmogorov to derive his refined similarity hypotheses [Kolmogorov, A refinement of previous hypotheses concerning the local structure of turbulence in a viscous incompressible fluid at high Reynolds number, J. Fluid Mech. 13, 82 (1962)], suggesting that ⋶_r is not, like ⋶, a quantity issuing from the Navier-Stokes equations.]]> Wed 04 Sep 2019 09:54:15 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:45594 Wed 02 Nov 2022 13:39:04 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36350 Wed 01 Apr 2020 16:34:32 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:44343 Tue 11 Oct 2022 19:28:32 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:33676 Tue 04 Dec 2018 16:13:50 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:35238 Tue 02 Jul 2019 15:21:49 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:30669 2) monolayer undergoes a semiconductor-to-metal transition and in this form bonds covalently to bilayers of Ge stacked in the [111] crystal direction. This gives rise to the stable bonding configuration of the MoTe₂/Ge interface with the ±K valley metallic, electronic interface states exclusively of a Mo 4d character. The atomically sharp Mo layer represents therefore an electrically active (conductive) subsurface δ-like two-dimensional profile that can exhibit a valley-Hall effect. Such system can develop into a key element of advanced semiconductor technology or a novel device concept.]]> Tue 02 Apr 2019 10:32:00 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:39187 Thu 26 May 2022 09:08:29 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36662 Thu 25 Jun 2020 10:45:29 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:53367 Thu 23 Nov 2023 10:56:13 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:52203 Thu 05 Oct 2023 10:08:39 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:3333 Sat 24 Mar 2018 10:57:10 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:7986 Sat 24 Mar 2018 10:45:22 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:9722 3 In atoms), the binding energy values of the additional In atoms adsorbed on Si(001) are essentially constant. All of the In structures formed in stages one and two which contain In monomers are determined to be metallic, while those consisting of only In-In dimers are semiconducting.]]> Sat 24 Mar 2018 08:42:24 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:7984 Sat 24 Mar 2018 08:35:50 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:7438 Sat 24 Mar 2018 08:35:15 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:11427 ∝(T_c-T) with T_c=237±2K. Octahedral tilting at high temperatures is closely similar to tilting in the Pnma structure of other perovskites, such as SrZrO₃. This is accompanied by a degree of Jahn-Teller ordering on the basis of the M⁺₂ scheme below ~775 K but is replaced by the Γ⁺₃ scheme below T_c. In contrast with the tilting and Jahn-Teller effects, magnetic ordering at the Néel temperature (~180 K) is accompanied by only the slightest volume strain and is not likely to influence the evolution of the other order parameters to any significant extent, therefore. An additional change in the volume strain below ~85 K is perhaps related to changes in magnetic structure at lower temperatures. Line broadening in powder diffraction patterns collected in the temperature interval ~150–260 K appears to be related to the presence of ferroelastic twins arising from octahedral tilting and draws attention to the fact that the Pnma↔IC transition takes place in a material which already contains heterogeneities. Finally, correlation of the repeat distance of the IC structure with Γ⁺₃ distortions of MnO₆ octahedra shows that the nature of the IC structure itself is also determined essentially by geometrical factors and strain.]]> Sat 24 Mar 2018 08:14:41 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:11043 Sat 24 Mar 2018 08:11:46 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:21577 p⁴P⁰ → 3s⁴P transitions of excited neutral nitrogen atoms created by the photofragmentation of the N₂ molecule with circularly polarized light having energies between 21 and 26 eV. The intensity measurements show the effect of predissociation of the N₂ Rydberg series R(C)¹Σ_u⁺states by non-Rydberg doubly excited resonances (NRDERs), while nonzero values of circular polarization allow us to unambiguously identify the presence of a directly excited NRDER with ¹Π_u symmetry in this energy range.]]> Sat 24 Mar 2018 08:00:42 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:26438 Sat 24 Mar 2018 07:27:28 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:26917 Sat 24 Mar 2018 07:23:33 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:32042 in situ loads in the absence of residual stress. This paper details an experimental proof of concept for this algorithm involving the full reconstruction of a biaxial strain field within a nontrivial steel sample. Aside from a small systematic error present within individual measurements, the experiment was a success and now serves as a practical demonstration of Bragg-edge transmission strain tomography for systems under in situ loads.]]> Mon 30 Oct 2023 14:43:21 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:41601 Mon 08 Aug 2022 08:53:12 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:39982 Fe₃GeTe₂ (FGT) can be largely modulated by a protonic gate. With the increase of the protons intercalated among vdW layers, interlayer magnetic coupling increases. Because of the existence of antiferromagnetic layers in FGT nanoflakes, the increasing interlayer magnetic coupling induces exchange bias in protonated FGT nanoflakes. Most strikingly, a rarely seen zero-field cooled (ZFC) exchange bias with very large values (maximally up to 1.2 kOe) has been observed when higher positive voltages (V_g ≥ 4.36  V) are applied to the protonic gate, which clearly demonstrates that a strong interlayer coupling is realized by proton intercalation. Such strong interlayer coupling will enable a wider range of applications for vdW magnets.]]> Fri 01 Jul 2022 10:33:31 AEST ]]>