In this paper, size distribution of nano-bubbles was measured by the reliable and fast method of laser diffraction technique. Nano-bubbles were produced using a nano-bubble generator designed and made based on hydrodynamic cavitation phenomenon in Venturi tubes. A Central Composite Design with Response Surface Methodology was used to conduct a five factor, five level factorial experimental desi...

Past research has confirmed the existence of surface nanobubbles on various hydrophobic substrates (static contact angle >90°) when imaged in air-equilibrated water. Additionally, the use of solvent exchange techniques (based on the difference in saturation levels of air in various solvents) also introduced surface nanobubbles on hydrophilic substrates (static contact angle <90°). In this work,...

in this paper, size distribution of nano-bubbles was measured by the reliable and fast method of laserdiffraction technique. nano-bubbles were produced using a nano-bubble generator designed and madebased on hydrodynamic cavitation phenomenon in venturi tubes. a central composite design withresponse surface methodology was used to conduct a five factor, five level factorial experimental designo...

Nanobubbles are considered to be one origin of characteristic behaviors of fluids in microscopic systems, such as boundary slip in channels and long-range attractive force acting between hydrophobic surfaces. In many recent experiments, nanobubbles on the hydrophobic substrates are observed with atomic force microscopy , infrared spectroscopy and other techniques. Observed nanobubbles are extra...

In this paper we propose a scaling argument to quantify the role of added electrolyte salt in affecting the stability and the morphology of preformed surface nanobubbles on hydrophobic substrates like the water-OTS-silicon or the water-HOPG interfaces. The added salt controls the electric double layer formation as well as affects the zeta (ζ) potential at the air-water and solid-water interface...

Nanobubbles (<200 nm in diameter) have several unique properties such as long lifetime in liquid owing to its negatively charged surface, and its high gas solubility into the liquid owing to its high internal pressure. They are used in variety of fields including diagnostic aids and drug delivery, while there are no reports assessing their effects on the growth of lives. Nanobubbles of air or o...

Surface nanobubbles emerging at solid-liquid interfaces of submerged hydrophobic surfaces show extreme stability and very small (gas-side) contact angles. In a recent paper Ducker [W. A. Ducker, Langmuir 25, 8907 (2009)] conjectured that these effects may arise from the presence of impurities at the air-water interface of the nanobubbles. In this paper we present a quantitative analysis of this...

Aqueous solutions of tetrahydrofuran, ethanol, urea, and alpha-cyclodextrin were studied by a combination of static and dynamic laser light scattering (LLS). In textbooks, these small organic molecules are soluble in water so that there should be no observable large structures or density fluctuation in either static or dynamic LLS. However, a slow mode has been consistently observed in these aq...

Nanobubbles, whose existence on hydrophobic surfaces immersed in water has previously been inferred from measurements of long-ranged attractions between such surfaces, are directly imaged by tapping mode atomic force microscopy. It is found that the nanobubbles cover the surfaces in an irregular, interconnected or close-packed network whose morphology is dependent on pH and whose lifetimes are ...

The long-ranged attractions between hydrophobic amorphous fluoropolymer surfaces are measured in water with and without dissolved air. An atomic force microscope is used to obtain more than 500 measured jump-in distances, which yields statistically reliable results. It is found that the range of the attraction and its variability is generally significantly decreased in deaerated water as compar...