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We consider classical second-order ghost imaging with uniformly partially polarized electromagnetic beams and examine the effect of the degree of polarization of the incident light on the visibility of the image. Closed-form expressions for two previously proposed definitions of visibility are derived. Both results are physically similar and show that the visibility increases with the degree of polarization. Hence, a polarized beam is superior to an unpolarized one to obtain a high-visibility ghost image. Some related issues in recent literature are also addressed.  相似文献   
105.
The tangents to the evaporation path curves in the W/O microemulsion base of water, (W), pentanol, (P), and sodium dodecyl sulfate, (S), were extended to the W/P axis to establish the relative composition, (WV, PV), of the vapor leaving the liquid.The composition of the vapor, with which the microemulsion is in contact includes also the contribution from the relative humidity of the surrounding atmosphere. The difference between the composition of these gases is clarified using the algebraic expressions from the phase diagram, but the quantitative composition of the equilibrium vapor is not available without further numerical information. The limits of the vapor for evaporation direction under different relative humidities were clarified.  相似文献   
106.
Three fragrances, phenethylalcohol, benzaldehyde, and limonene (that differ in their polarity), were solubilized in lamellar liquid crystal using the polyethylene oxide-polypropylene oxide-polyethylene oxide, (EO27PO61EO27), P104 triblock copolymer, and water. The interlayer spacing of the lamellar liquid crystal were established using small angle X-ray scattering (SAXS). The SAXS data are used to calculate the interfacial area per polyethylene oxide (PEO) block and to determine the location of each fragrance in the association structure. The results show the presence of phenethylalcohol at the interface while part of benzaldehyde contributing to the interface and the other part being located inside the polar/apolar domains. The third fragrance, limonene, did not participate in the formation of the interface and is located inside the apolar domain.  相似文献   
107.
Polypropylene surfaces were rendered cationic by hydrophobic implantation and by grafting a quaternized polyvinyl pyridine onto a plasma treated surface. The polypropylene surface with the grafted polymer showed a strong adsorption of an anionic surfactant, corresponding to about ten monomolecular layers. High concentration of electrolyte caused a reduction of the adsorption at low concentrations of surfactant.  相似文献   
108.
Phase maps were determined in the system water, sodium dodocyl sulfate, pentanol and a commercial mineral oil (Drakeol® 7) and the dimensions in the lamellar liquid crystal were determined using low angle x-ray diffraction. The mineral oil gave a strong reduction in the water-in-oil microemulsion region solubilization capacity for water when combined with the cosurfactant in a 1/1 weight ratio. For less oil/cosurfactant ratios a large oil-in-water microemulsion region was observed

The mineral oil added to the liquid crystal in the system strongly reduced the water penetration into the hydrocarbon chain region and enhanced the disorder of the hydrocarbon chains in the structure.  相似文献   
109.
ABSTRACT

The phase diagram of water, phenethyl alcohol (PEA) and the triblock copolymer EO4.5PO59EO4.5, (EO = ethylene oxide, PO = propylene oxide), L101, was determined and the vapor pressures of PEA were measured for different phases.

The phase diagram was almost identical to the corresponding one with a simple nonionic surfactant, Laureth 4, (?C12EO4), but the PEA vapor pressure variation with mole fraction was significantly different reflecting the strong molecular interaction between PEA and the polymer. This distinction was mainly due to difference in molecular size; vapor pressure plots against weight fraction gave curves with only moderate variance.

The results were used to discuss the variation in the PEA vapor pressure with time after application of a vesicular solution of PEA stabilized either by L101 or Laureth 4. The moderate differences in vapor pressures had a significant influence on the estimated curves of PEA pressure versus time.  相似文献   
110.
The lamellar liquid crystalline phase in the system consisting of sodium oleate (NaOL), oleic acid (OLA), and water was determined. The interlayer spacing (d) of the lamellar liquid crystal was measured through small angle X-ray diffraction, which indicated that oleic acid molecules were solubilized between the end methyl groups at low concentrations, and then were located within the hydrocarbon chain layer with further increase of its concentration. Cross-linking agents were added to the system, which were found being located partly in between the end methyl groups and partly within the hydrocarbon chain layers. The liquid crystal phase of NaOL/OLA/H2O system with the cross-linking agent was polymerized at 60 °C, which turned out to be a mixture of liquid crystals and solids. Interlayer spacing decreased by about 10 Å, indicating a disruption of the ordered structure by the polymerization. The polymerization took place not only within the hydrocarbon layer, but also in between the layers separated by the end methyl groups. The resulting polymer lowered the surface tension of water to below 30 mN/m, with a critical micellization concentration of about O.25g/L.  相似文献   
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