Spin vortices

In the previous section, we have presented the evidence that the small polaron is an important ingredient of the cuprate superconductivity. In this section, we show that the spin-vortex is another important ingredient. 

The spin-vortex model assumes the existence of spin-vortices with their centers at small polarons. It is also assumed that the system response to the incident... 

In Fig. 15, magnetic excitation spectra calculated by the spin-vortex model are depicted. Results obtained by the Holstein-Primakoff method are also depicted. The dispersions exhibit hourglass-shapes. As the number of spin-vortices are increased, the peaks of the dispersion become blur. The neck energy increases with the increase of the number of holes in agreement with experiment. 

By now, we have identified three important ingredients in the cuprate superconductivity strong on-site Coulomb repulsion, small polaron formation, and spin-vortex formation. With all these ingredients, however, the conventional transport theory based on Bloch electrons will predict that the system is an insulator. In order to... 

Fig. 21 Plots obtained by mean-field calculations for an EHFMI [24]. Calculations are performed for a two-dimensional 16x16 square lattice with open boundary conditions. Parameters used are U = St and t = —0.2t t denotes the second nearest neighbor transfer integrals tjk)- The number of doped holes is 8 half of them are centers of merons and the rest are centers of antimerons. (a) Plot for spin configuration. Centers of spin vortices are indicated as M for a meron (winding number -H spin vortex) and A for an antimeron (winding number —1 spin vortex), respectively, (b) Plot for current density j (short black arrows) and V x (long orange arrows). M and A here indicate centers of counterclockwise and clockwise loop currents, respectively (c) Plot for D(x), which connects j(x) and V/(x) as j(x) = D(x) V/(x) (d) Plot for 2j (thick orange line arrows are not attached but directions are the same as those of the black arrows) and 2Z)(x) V/(x) (black arrows)...

In the cuprate, holes are expected to exist at each center of loop currents thus, if we arrange holes in this way artificially, a persistent current will be generated, even if the hole concentration is x < 0.05. Instead of holes, we may use some atoms (for example, Mn may be appropriate as is suggested by the result in [16]) as centers of loop currents. In this way, we may obtain an enhanced stability in spin vortices. If we find a way to construct such a spin-vortex structure that is similar to one given in Fig. 25, and which is robust even at room temperatures, a room temperature superconductivity may be realized. 

Resuspend in 3.0 pi formamide dye loading buffer. Spin, vortex, spin. 

The Spin Velocity Under the inviscid flow assumption, where all fluid that enters the cyclone does so with approximately the same amount of momentum, a free vortex may be predicted for the spin velocity distribution as... 

Normally the vortex finder should extend down into the conical portion of the cyclone. It is thought that the vortex finder plays an important role in the maintenance of a stable spiraling fluid flow in the cyclone, and this makes it more difficult for the particles to leak through the boundary layer on the roof of the lid of the cyclone to the overflow tube.- Without a vortex finder, the efficiency may be reduced by 4-5%. However, an excessive long vortex finder may hinder the high spin velocity in the fluid flow and thus reduce the efficiency of the cyclone. 

Figure 2. Radial-axial velocity field and temperature contours for a rotating-disk reactor at an operating condition where a buoyancy-driven recirculation vortex has developed. The disk temperature is HOOK, the Reynolds number is 1000, Gr/Re / = 6.2, fo/f = 1.28, and L/f = 2.16. The disk radius is 4.9 cm, the spin rate is 495 rpm. The maximum axial velocity is 55.3 cm/sec. The gas is helium.

Fig. 4.4.7 (a) Reconstruction of the Stationary Helical Vortex (SHV) mode from MRI data acquired with the spin-tagging spin-echo sequence [27], The axial flow is upwards and the inner cylinder is rotating clockwise. The two helices represent the counter-rotating vortex streamtubes. (b) Construction of Poincare map for SHV [41]. The orbit of a typical particle is... 

Discard the supernatant and resuspend the pellet in 650 1 RNase-free water. Add an equal volume of water-saturated phenol chloroform (5 1), pH 5.2. Vortex vigorously and spin at top speed for 5 min at room temperature. Take 500 pi of the aqueous phase into a new microtube tube. 

Mix by vortexing, then place the tube in a microcentrifuge and spin for 5 minutes at maximal rpm. 

Cool die sample in an ice bath and add 1/10 volume of Soln. A. Vortex and allow to precipitate in an ice bath for 30 min. Spin for 5 min at 5000 to 10 000 x g in a refrigerated centrifuge. Remove the supernatant by aspiration with a pipet. Wash the pellet once with 0.5 sample volume ice-cold 10% TCA (w/v) and once with 0.5 sample volume ice-cold ethanol-ether 1 1 (v/v) to remove traces of TCA. Dry the pellet at the air and dissolve in 0.1 N NaOH or 0.1 M Tris pH 8.0. 

If proteins were expressed within cells of cell cultures, the cells have to be disrupted as gently as possible. For instance, incubate 10 to 10 cells in 1 ml Soln. B at 0 °C for 30 min. Vortex and spin at 250 X g. Transfer the supernatant into a new tube and centrifuge at 13.000 X g for 10 min. 

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