We propose an experimental setup to measure the threshold pressure gradient (TPG) of microchannels with different wettability surfaces by the static method in microchannels with diameters from 20 μm to 320 μm, and...We propose an experimental setup to measure the threshold pressure gradient (TPG) of microchannels with different wettability surfaces by the static method in microchannels with diameters from 20 μm to 320 μm, and compare the TPG of microchannels with adsorption of cetyl trimethyl ammonium bromide (CTAB) with that without CTAB adsorption. The results show the existence of TPG in microchannels. The TPG of microchannels increases with decreasing hydrodynamic diameter, and the relation between TPG and diameter is in agreement with the single-log normalization. The TPG of a microchannel with CTAB adsorption decreases obviously as compared with the microchannel without CTAB adsorption. The TPG of microchannels with different wettabilities of boundary surface are different, and the resistance of liquid flow can be reduced by changing the wettability of boundary surfaces.展开更多
Effects of variable viscosity on the flow and heat transfer in a thin film on a horizontal porous stretching sheet are analyzed. The steady boundary layer equations for momentum and thermal energy are simplified by us...Effects of variable viscosity on the flow and heat transfer in a thin film on a horizontal porous stretching sheet are analyzed. The steady boundary layer equations for momentum and thermal energy are simplified by using similarity transformations. The resulted and coupled nonlinear differential equations are solved by Homotopy analysis method. The results are presented graphically to interpret various physical parameters appearing in the problem.展开更多
Evolution of viscosity of some aqueous poly (ethylene oxide) gels is observed as functions of polymeric concentration and temperature for samples subjected to thermal shock. The experimental data are analyzed follow...Evolution of viscosity of some aqueous poly (ethylene oxide) gels is observed as functions of polymeric concentration and temperature for samples subjected to thermal shock. The experimental data are analyzed following an appropriate algorithm, and reveal the transient effect from Newtonian to non-Newtonian flow as a function of the polymeric concentration.展开更多
We report on a first observation of a floating- spherical Hg (density 13g/cm3) drop on top of a glycerin (density 1.26g/cm3) drop, the latter is hemispherical and about four times larger in volume. This observatio...We report on a first observation of a floating- spherical Hg (density 13g/cm3) drop on top of a glycerin (density 1.26g/cm3) drop, the latter is hemispherical and about four times larger in volume. This observation is clearly against nature's gravity law and has never been reported before. Here we present spectacular high resolution photos that clearly demonstrate this remarkable floating phenomenon. Using milli-Q water, the Hg drop would stay down adhered at the triple line. Instead, the coincidental use of tap water displays the same phenomenon. Increasing the volume of the supporting liquid to a certain value causes the Hg drop to sink. A 5-M NaCl aqueous solution is found enough to show the same floating phenomenon. This floating mercury as a phenomenon is puzzling. On this length scale it seems that surface tension and curvature dominate over gravity.展开更多
A drug delivery system via multi-walled carbon nanotube (MWNT) vehicle was synthesized in aqueous solution. MWNTs were first noncovalently functionalized with chitosan oligomers (CS) with a molecule weight of 4000...A drug delivery system via multi-walled carbon nanotube (MWNT) vehicle was synthesized in aqueous solution. MWNTs were first noncovalently functionalized with chitosan oligomers (CS) with a molecule weight of 4000-6000, making MWNTs water-soluble, and then a cancer ancillary drug tea polyphenols (TP) was conjugated mainly via the hydrogen bond between CS and TP molecules, making MWNTs efficient vehicle for drug delivering. The release of drug molecules can be realized by pH variation and γ-radiation, leading to new methods for controlling drug release from carbon nanotubes carrier. Due to the high penetrability of γ-rays, γ-radiation shows up new opportunities in controlled drug release, possibly facilitating the future cancer treatment in vivo.展开更多
This report adds three protonic semiconductor models to explain the "abnormally" high electrical conductivity of pure liquid water characterized by the three industrial consensus parameters, the ion product(...This report adds three protonic semiconductor models to explain the "abnormally" high electrical conductivity of pure liquid water characterized by the three industrial consensus parameters, the ion product(or pH)and the two ion mobilities. Existence of long-range order in fluid water under numerous daily conditions led us to extend the 1933 Bernal-Fowler hexagonally close packed crystalline Ice Lattice to model liquid water as Melted Ice. Protonic kinetic energy band and bound(trap) pictures provide semiconductor-physics based new models of these three parameters. They are extrapolatable engineered-models for developing novel biological, chemical, electrical, mechanical and medical applications of liquid water.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 10972199, and the Natural Science Foundation of Zhejiang Province under Grant No Y607425.
文摘We propose an experimental setup to measure the threshold pressure gradient (TPG) of microchannels with different wettability surfaces by the static method in microchannels with diameters from 20 μm to 320 μm, and compare the TPG of microchannels with adsorption of cetyl trimethyl ammonium bromide (CTAB) with that without CTAB adsorption. The results show the existence of TPG in microchannels. The TPG of microchannels increases with decreasing hydrodynamic diameter, and the relation between TPG and diameter is in agreement with the single-log normalization. The TPG of a microchannel with CTAB adsorption decreases obviously as compared with the microchannel without CTAB adsorption. The TPG of microchannels with different wettabilities of boundary surface are different, and the resistance of liquid flow can be reduced by changing the wettability of boundary surfaces.
文摘Effects of variable viscosity on the flow and heat transfer in a thin film on a horizontal porous stretching sheet are analyzed. The steady boundary layer equations for momentum and thermal energy are simplified by using similarity transformations. The resulted and coupled nonlinear differential equations are solved by Homotopy analysis method. The results are presented graphically to interpret various physical parameters appearing in the problem.
文摘Evolution of viscosity of some aqueous poly (ethylene oxide) gels is observed as functions of polymeric concentration and temperature for samples subjected to thermal shock. The experimental data are analyzed following an appropriate algorithm, and reveal the transient effect from Newtonian to non-Newtonian flow as a function of the polymeric concentration.
文摘We report on a first observation of a floating- spherical Hg (density 13g/cm3) drop on top of a glycerin (density 1.26g/cm3) drop, the latter is hemispherical and about four times larger in volume. This observation is clearly against nature's gravity law and has never been reported before. Here we present spectacular high resolution photos that clearly demonstrate this remarkable floating phenomenon. Using milli-Q water, the Hg drop would stay down adhered at the triple line. Instead, the coincidental use of tap water displays the same phenomenon. Increasing the volume of the supporting liquid to a certain value causes the Hg drop to sink. A 5-M NaCl aqueous solution is found enough to show the same floating phenomenon. This floating mercury as a phenomenon is puzzling. On this length scale it seems that surface tension and curvature dominate over gravity.
文摘A drug delivery system via multi-walled carbon nanotube (MWNT) vehicle was synthesized in aqueous solution. MWNTs were first noncovalently functionalized with chitosan oligomers (CS) with a molecule weight of 4000-6000, making MWNTs water-soluble, and then a cancer ancillary drug tea polyphenols (TP) was conjugated mainly via the hydrogen bond between CS and TP molecules, making MWNTs efficient vehicle for drug delivering. The release of drug molecules can be realized by pH variation and γ-radiation, leading to new methods for controlling drug release from carbon nanotubes carrier. Due to the high penetrability of γ-rays, γ-radiation shows up new opportunities in controlled drug release, possibly facilitating the future cancer treatment in vivo.
基金funded by the National Natural Science Foundation of China
文摘This report adds three protonic semiconductor models to explain the "abnormally" high electrical conductivity of pure liquid water characterized by the three industrial consensus parameters, the ion product(or pH)and the two ion mobilities. Existence of long-range order in fluid water under numerous daily conditions led us to extend the 1933 Bernal-Fowler hexagonally close packed crystalline Ice Lattice to model liquid water as Melted Ice. Protonic kinetic energy band and bound(trap) pictures provide semiconductor-physics based new models of these three parameters. They are extrapolatable engineered-models for developing novel biological, chemical, electrical, mechanical and medical applications of liquid water.