XPS valence band observable light-responsive system for photocatalytic acid Red114 dye decomposition using a ZnO-CuO heterojunction.

ZnO-CuO composites were made as photocatalysts in a range of different amounts using an easy, cheap, and environment-friendly coprecipitation method due to their superior visible light activity to remove pollutants from the surrounding atmosphere. X-ray diffraction and Fourier transform infrared spectroscopy (FT-IR) have demonstrated that ZnO-CuO catalysts are made of highly pure hexagonal ZnO and cubic CuO. X-ray photoelectron spectroscopy has confirmed that there is a substantial interaction between the two phases of the resultant catalyst.

Studies on Synthesis, Characterization, and Photocatalytic Activity of TiO and Cr-Doped TiO for the Degradation of -Chlorophenol.

TiO and Cr-TiO nanoparticles (NPs) have been synthesized by the sol-gel method using titanium isopropoxide as the precursor of Titania. The prepared samples were analyzed by employing scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Fourier transform infrared analyses. Under UV irradiation, the photocatalytic activities of TiO and Cr-TiO were observed by estimating the % degradation of -chlorophenol (PCP) as a sample pollutant.

Interactions of l-arginine with Langmuir monolayers of common phospholipids at the air-water interface.

The interactions of l-arginine (l-arg) with Langmuir monolayers of three most common phospholipids, which are sodium salt of dipalmitoylphosphatidylglycerol (DPPG), dipalmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylethanolamine (DPPE), have been investigated at the air-water interface. The surface pressure-area (π-A) isotherms of these monolayers have been measured with a film balance and monolayer morphology has been observed by a Brewster angle microscopy (BAM). The DPPG monolayers on pure water do not show any phase transition but show irregular shaped condensed phases formed just after evaporation of the solvent at 20 °C.

Temperature dependent dendritic domain shapes in Langmuir monolayers of tetradecanoyl N-ethanolamide at the air-water interface.

The effect of temperature on the surface phase behavior of tetradecanoyl N-ethanolamide (NHEA-14) in Langmuir monolayers at the air-water interface has been investigated by film balance and Brewster angle microscopy (BAM). It has been observed that dendritic domains are formed in the coexistence region between liquid-expanded (LE) and liquid-condensed (LC) phases at different temperatures. At 10 and 15°C, the domains are four-armed dendrites having wide arms which have a tendency to be fractal while growing in size.

Effect of head groups on the phase transitions in Gibbs adsorption layers at the air-water interface.

The adsorption kinetics and the surface phase behavior of four different amphiphiles, which are 2-hydroxyethyl laurate (2-HEL), dodecanoyl N-ethanolamide (NHEA-12), dodecanoyl N-methylethanolamide (NMEA-12) and tetradecanoyl N-methylethanolamide (NMEA-14), have been investigated at the air-water interface by film balance, surface tensiometer and Brewster angle microscopy (BAM). The former two amphiphiles show a first-order phase transition from a lower density liquid like phase to a higher density condensed phase in Gibbs adsorption layers. On the other hand, the latter two amphiphiles are unable to show such characteristics under any experimental conditions.

Temperature and compression rate independent domain shape in Langmuir monolayers of di-n-dodecyl hydrogen phosphate at the air-water interface.

Thermodynamic and morphological properties of Langmuir monolayers of di-n-dodecyl hydrogen phosphate (DDP) have been studied by film balance and Brewster angle microscopy (BAM) over a wide range of temperature between 5 and 40 degrees C. From pi-A isotherms, a generalized phase diagram consisting of gas (G), liquid expanded (LE) and liquid condensed (LC) phases is constructed for the DDP monolayers. The BAM images show the formation of gas bubble in the bright background of LE phase during G-LE phase transitions and fingering LC domains during LE-LC phase transitions.

How many phases and phase transitions do exist in Gibbs adsorption layers at the air-water interface?

Four different phases and four different first-order phase transitions have been shown to exist in Gibbs adsorption layers of mixtures containing n-hexadecyl dihydrogen phosphate (n-HDP) and L-arginine (L-arg) at a molar ratio of 1:2. These conclusions have been made from surface pressure-time (pi-t) adsorption isotherms measured with a film balance and from monolayer morphology observed with a Brewster angle microscopy (BAM). The observed four phases are gas (G), liquid expanded (LE), liquid condensed (LC) and LC' phases.

Interactions of L-arginine with Langmuir monolayers of di-n-dodecyl hydrogen phosphate at the air-water interface.

The surface phase behavior of di-n-dodecyl hydrogen phosphate (DDP) in Langmuir monolayer and its interactions with L-arginine (L-arg) have been investigated by measuring pi-A isotherms with a film balance and observing monolayer morphology with a Brewster angle microscopy (BAM). The DDP monolayers on pure water show a first-order liquid expanded-liquid condensed (LE-LC) phase transition and form fingering LC domains having uniform brightness at different temperatures. At 15 degrees C, the pi-A isotherms on pure water and on different concentration solutions of L-arg show a limiting molecular area at approximately 0.

Surface phase behavior of di-n-tetradecyl hydrogen phosphate in Langmuir monolayers at the air-water interface.

Surface phase behavior of di-n-tetradecyl hydrogen phosphate, DTP, has been studied by measuring pi-A isotherms with a film balance and observing monolayer morphology with a Brewster angle microscopy (BAM) at different temperatures. A generalized phase diagram, which shows a triple point for gas (G), liquid-expanded (LE) and liquid-condensed (LC) phases at about 32 degrees C, is constructed for the amphiphile. Below the triple point, a first-order G-LC phase transition has been shown to occur, whereas a first-order G-LE phase transition followed by another first-order LE-LC transition has been found to take place at a temperature above the triple point.

Kinetic appearance of first-order gas-liquid expanded and liquid expanded-liquid condensed phase transitions below the triple point.

Phase diagram of Gibbs monolayers of mixtures containing n-hexadecyl phosphate (n-HDP) and L-arginine (L-arg) at a molar ratio of 1:2 has been constructed by measuring surface-pressure-time (pi-t) isotherms with film balance and by observing monolayer morphology with Brewster angle microscopy (BAM). This phase diagram shows a triple point for gas (G), liquid expanded (LE), and liquid condensed (LC) phases at around 6.7 degrees C.

Effect of temperature on the surface phase behavior of n-hexadecyl dihydrogen phosphate in adsorption layers at the air-water interface.

We present the adsorption kinetics and the surface phase behavior of n-hexadecyl dihydrogen phosphate (n-HDP) at the air-water interface by film balance and Brewster angle microscopy (BAM). A phase diagram, which shows a triple point at about 25.8 degrees C, is constructed by measuring the surface pressure (pi)-time (t) adsorption isotherms.

Interaction of an organic cation with Gibbs monolayers of n-hexadecyl phosphate.

Surface phase behavior of n-hexadecyl phosphate (n-HDP) and its mixture with L-arginine (L-arg), which behaves as L-argininium cation (L-arg(+)) in aqueous solution, at a molar ratio 2:3 in Gibbs adsorption layers has been studied by film balance, Brewster angle microscopy (BAM) and surface tensiometry at 20 degrees C. The monolayers of n-HDP show three phases that are gas (G), intermediate (I) and liquid condensed (LC), and two phase transitions. A first-order G-I phase transition that is followed by a second-order I-LC phase transition is found in these monolayers.

Phases and phase transitions in Gibbs monolayers of an alkyl phosphate surfactant.

We present the adsorption kinetics and the surface phase behavior of water-soluble n-tetradecyl phosphate (n-TDP) at the air-water interface by film balance and Brewster angle microscopy (BAM). The relaxation of the surface pressure at about zero value in the surface pressure (pi)-time (t) adsorption isotherm is found to occur from 2 to 20 degrees C with appropriate concentrations of the amphiphile. These plateaus are accompanied by two surface phases, confirming that the relaxation of the surface pressure is caused by a first-order phase transition.