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Rongjia Tao: Influence Statistics

The yield stress of magnetorheological (MR) fluids depends on the induced solid structure. Since thick columns have a yield stress much higher than a single-chain structure, we improve the yield stress of MR fluids by changing the fluid microstructure. Immediately after a magnetic field is applied, we compress the MR fluid along the field direction. Scanning electron microscopy images show that particle chains are pushed together to form thick columns. The shear force measured after the ...

A method with pulsed electric or magnetic field to reduce the viscosity of crude oil is developed. Specifically, for paraffin-base crude oil, a magnetic field pulse can effectively reduce its viscosity for several hours, while, for asphalt-base crude oil or mixed-base crude oil, an electric field pulse can do the same. The method does not change the temperature of the crude oil; instead, it temporary aggregates paraffin particles or asphaltene particles inside the crude oil into large ...

Blood viscosity is a major factor in heart disease. When blood viscosity increases, it damages blood vessels and increases the risk of heart attacks. Currently, the only method of treatment is to take drugs such as aspirin, which has, however, several unwanted side effects. Here we report our finding that blood viscosity can be reduced with magnetic fields of 1 T or above in the blood flow direction. One magnetic field pulse of 1.3 T lasting ~1 min can reduce the blood viscosity by ...

Reducing the crude oil viscosity is important for the oil production and transportation. The micro–nanotechnology of viscosity reduction associated with electric field is found to be universal, working for all kinds of crude oil, including asphalt base crude oil and paraffin base crude oil. Especially at low temperature, the electric field is extremely efficient: in a couple of seconds after the electric field is applied, the viscosity is reduced substantially, making the flow rate in a ...

To enhance the yield shear stress of magnetorheological (MR) fluids is an important task. Since thick columns have a yield stress much higher than a single-chain structure, we enhance the yield stress of an MR fluids by changing the microstructure of MR fluids. Immediately after a magnetic field is applied, we compress the MR fluid along the field direction. SEM images show that the particle chains are pushed together to form thick columns. The shear force measured after the compression ...

High- Tc superconducting particles of μm size in a strong electric field bind themselves together to form macroscopic balls in milliseconds. Each ball holds over 106 particles and bounces between the electrodes without losing any. The ball formation is a result of superconductivity. As the c-axis coherence length is shorter than the Thomas-Fermi screening length, the electric field produced by the charged surface layer turns off the coupling between the interlayers. This loss of ...

The temporal evolution of three-dimensional structure in an electrorheological (ER) fluid is examined by a computer simulation. A parameter B characterizing the ratio of the Brownian force to the dipolar force is introduced. For a wide range of B, the ER fluid has a rapid chain formation followed by aggregation of chains into thick columns which has a body-centered tetragonal lattice structure. The Peierls-Landau instability of single chains help formation of thick columns. If the ...

We discuss the periodic boundary condition, degeneracy of the ground state, impurity effect, and topological invariant in the quantum Hall effect. If a two-dimensional electron Hall system with a uniform background is confined on a toroidal geometry, the ground state is q-fold degenerate at filling factor ν=p/q when there is an energy gap Δ. Weak impurities make the ground state quasi- degenerate. If the driving force of the Hall current has some low but finite speed, or the applied ...

Improving engine efficiency and reducing pollutant emissions are extremely important. Here, we report our fuel injection technology based on the new physics principle that proper application of electrorheology can reduce the viscosity of petroleum fuels. A small device is thus introduced just before the fuel injection for the engine, producing a strong electric field to reduce the fuel viscosity, resulting in much smaller fuel droplets in atomization. Because combustion starts at the ...

It is shown that gauge-invariance arguments imply the possibility of the fractional quantum Hall effect; the Hall conductance is accurately quantized to a rational value. The ground state of a system showing the fractional quantum Hall effect must be degenerate; the nondegenerate ground state can only produce the integral quantum Hall effect.

A shear flow of one-component polarizable fluid in a strong electric field has a structural transition at a critical shear stress. When the shear stress is increased from zero up to the critical shear stress, the flow (in the x direction) has a flowing-chain (FC) structure, consisting of tilted or broken chains along the field (z direction). At the critical shear stress, the FC structure gives way to a flowing-hexagonal-layered (FHL) structure, consisting of several two-dimensional ...

We use Monte Carlo simulations to investigate the ground state of electrorheological (ER) fluids in a strong electric field. Our results suggest a body-centered tetragonal (bct) lattice with conventional Bravais vectors a1= √6 ax^, a2= √6 ay^, and a3=2az^ where a is the radius of dielectric spheres and the z axis is the direction of the applied electric field. This bct lattice can be regarded as a compound of chains of class A and class B where chains of class B are obtained from chains ...

Electric field and magnetic field can be applied to any liquid suspensions with a discrepancy in permittivity or permeability between the suspended contents and the base liquid (Tao et al., 2014, 2016; Du et al., 2011; Tao et al., 2011; Huang et al., 2011). As we know, the diesel has some benefits compared to gasoline (Aoyagi et al., 2006). And the fractional distillate of petroleum fuel oil has the limited reserve. Fortunately, the biodiesel can be used for the petroleum diesel engines ...

The induced electrorheological solid has thick columns in the field direction (z axis), spreading between two electrodes. The ground state is proposed to be a body-centered tetragonal lattice with a1= √6 ax^, a2= √6 ay^, and a3=2az^, where a is the radius of dielectric spheres. This bct lattice can be regarded as a compound of chains of class A and B, where chains B are obtained from chains A by shifting a distance a in the z direction.