Studies on the Effect of Anionic Surfactant on the Microemulsion System Containing [60]Fullerene

2016 ◽  
Vol 32 (1-2) ◽  
pp. 21
Author(s):  
Vaishali Suthar ◽  
C. N. Murthy
Keyword(s):  
Thermodynamic Properties ◽  
Anionic Surfactant ◽  
Reverse Micelle ◽  
Water Quantity ◽  
Microemulsion System ◽  
Fullerene Solution ◽  
Potential Applications ◽  
Significant Change

Fullerenes have potential applications in the form of microemulsion systems. Microemulsion studies with various alcohols as co-surfactants reveals that as the co-surfactant was changed from propanol to octanol, the water quantity in the microemulsion was less when [60]fullerene was present in the oil. The microemulsion region increases when [ 60]fullerene is present along with co-surfactants like propanol, butanol and pentanol and decreases when hexanol and octanol were present. The thermodynamic properties (ΔG°, ΔH° and ΔS°) of reverse micellisation of SDS in toluene-[60]fullerene solution at 30ºC and 40ºC were calculated and the results show that though there is no significant change in the overall ΔG°, there was significant decrease in the enthalpic interactions with a corresponding increase in the entropy for reverse micellization in toluene. The values of ΔG°, ΔH° and ΔS° are negative indicating the spontaneous and exothermic formation of a reverse micelle.

The Design of Organic Gelators Based on a Family of Bis-Ureas

1999 ◽  
Vol 604 ◽  
Author(s):  
Rosa E. Meléndez ◽  
Andrew J. Carn ◽  
Kazuki Sada ◽  
Andrew D. Hamilton
Keyword(s):  
Thermodynamic Properties ◽  
Organic Solvents ◽  
Organic Molecules ◽  
Materials Science ◽  
Crystallographic Data ◽  
Porous Solids ◽  
X Ray ◽  
Molecule Structure ◽  
Structure Activity ◽  
Potential Applications

AbstractThe use of organic molecules as gelators in certain organic solvents has been the target of recent research in materials science. The types of structures formed in the gel matrix have potential applications as porous solids that can be used as absorbents or in catalysis. We will present and discuss the organogelation properties of a family of bis-ureas. Studies presented will include a molecule structure activity relationship, thermodynamic properties, comparison to x-ray crystallographic data and potential functionalization of the gels formed by this class of compounds

scholarly journals The Radiative, Cloud, and Thermodynamic Properties of the Major Tropical Western Pacific Cloud Regimes

2005 ◽  
Vol 18 (8) ◽  
pp. 1203-1215 ◽  
Author(s):  
Christian Jakob ◽  
George Tselioudis ◽  
Timothy Hume
Keyword(s):  
Thermodynamic Properties ◽  
Thermodynamic Characteristics ◽  
The Other ◽  
Western Pacific ◽  
Cloud Properties ◽  
Tropical Western Pacific ◽  
Potential Applications ◽  
Shallow Clouds ◽  
Atmospheric Radiation Measurement ◽  
Cloud Regimes

Abstract This study investigates the radiative, cloud, and thermodynamic characteristics of the atmosphere separated into objectively defined cloud regimes in the tropical western Pacific (TWP). A cluster analysis is applied to 2 yr of daytime-only data from the International Satellite Cloud Climatology Project (ISCCP) to identify four major cloud regimes in the TWP region. A variety of data collected at the Department of Energy’s Atmospheric Radiation Measurement Program (ARM) site on Manus Island is then used to identify the main characteristics of the regimes. Those include surface and top-of-the-atmosphere radiative fluxes and cloud properties derived from a suite of ground-based active remote sensors, as well as the temperature and water vapor distribution measured from radiosondes. The major cloud regimes identified in the TWP area are two suppressed regimes—one dominated by the occurrence of mostly shallow clouds, the other by thin cirrus—as well as two convectively active regimes—one exhibiting a large coverage of optically thin cirrus clouds, the other characterized by a large coverage with optically thick clouds. All four of these TWP cloud regimes are shown to exist with varying frequency of occurrence at the ARM site at Manus. It is further shown that the detailed data available at that site can be used to characterize the radiative, cloud, and thermodynamic properties of each of the regimes, demonstrating the potential of the regime separation to facilitate the extrapolation of observations at one location to larger scales. A variety of other potential applications of the regime separation are discussed.

scholarly journals Entrapment of Glucose Oxidase in Reverse Micelle Microemulsion Systems for Glucose Detection in Lipid Based Food Products

2019 ◽  
Vol 31 (11) ◽  
pp. 2635-2641
Author(s):  
Lovnish Siyal ◽  
Benu Kumar ◽  
Arpita Bhattacharya ◽  
Rachana Sahney
Keyword(s):  
Glucose Oxidase ◽  
Reverse Micelle ◽  
Food Products ◽  
Microemulsion System ◽  
Glucose Content ◽  
Activity Maximum ◽  
Maximum Reaction Rate ◽  
New Information ◽  
Maximum Reaction ◽  
Turn Over

Entrapment of glucose oxidase (GOx) enzyme in a new reverse micelle emulsion system was studied. The microemulsion consists of aqueous phase (buffered enzyme)/SPAN 85/n-decane. Critical micelle concentration (CMC) of surfactant-SPAN 85 in n-decane was determined using dynamic light scattering study and it was used to develop microemulsion system. Most stable and optically transparent microemulsion with entrapped glucose oxidase showed higher values of specific enzyme activity, maximum reaction rate (Vmax) and turn over number and low value of Michaelis-constant (Km) in comparison to homogeneous GOx (enzyme-glucose oxidase) system. The microemulsion system was successfully used to quantify D-glucose in lipid based food products without any sample preparation. Comparison of these results with chemical method (phenol-sulfuric acid method) and commercial kit method used in food industry validate the efficiency of the new proposed system. The study provides new information about the glucose content of some commonly consumed milk based products where nutritional labels do not accurately show true glucose content. These findings provide support for comprehensive glucose labeling to food products commonly used by the children.

EFFECT OF REVERSE MICELLE WATER POOL IN SYNTHESIS OF ZIRCONIA STABILIZED COPPER NANOCOMPOSITE

2012 ◽  
Vol 05 ◽  
pp. 559-567
Author(s):  
H. Abdizadeh ◽  
Y. Vahidshad ◽  
H. R. Baharvandi ◽  
M. Akbari Baseri
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Physical Properties ◽  
Size Distribution ◽  
Anionic Surfactant ◽  
Reverse Micelle ◽  
Sol Gel ◽  
Molar Ratio ◽  
Water Pool ◽  
20 Nm

In the water-in-oil (W/O) microemulsions based on anionic (AOT) surfactants, the ω value (molar ratio of water to surfactant), precursor, and surfactant could remarkably affect the synthesis of CuO - ZrO 2 nanocomposite and the morphologies of the sol-gel products simultaneously. In this study, CuO - ZrO 2 nanoparticles are synthesized using microreactors made of surfactant/water/n-hexane microemulsions and discusses the effect of different microemulsion variables on the particle size and particle size distribution by water-to-surfactant molar ratio. The obtained powders are characterized by DTA, XRD, SEM, EDS, and TEM and their physical properties are compared. For AOT surfactant the particle size increased with increasing the water to surfactant molar ratio. The particles size of CuO - ZrO 2 nanocomposite in sample with anionic surfactant with molar ratio of 6 that calcined at 600°C is between 15-20 nm.

First-Principles Calculations on Crystal Structure and Thermodynamic Properties of Ceramics

2007 ◽  
Vol 336-338 ◽  
pp. 2517-2520
Author(s):  
Yue Zhang ◽  
Xue Gao ◽  
Jia Xiang Shang ◽  
Xiao Ping Han
Keyword(s):  
Thermodynamic Properties ◽  
First Principles ◽  
Density Functional ◽  
Alloy Element ◽  
Material System ◽  
First Principles Calculations ◽  
Densities Of States ◽  
Potential Applications ◽  
Bonding Properties ◽  
New Material

First-principles calculations have been widely used to describe the ground state properties of materials over almost 20 years. Recently, a great progress was made in the first-principle calculations. Thermodynamic properties can also be gotten by calculations of the phonon densities of states (phonon DOS) and phonon dispersions of materials, which show widely potential applications in material researches. In the present work, the energetics and bonding properties of interfaces between ZrO2 and Ni metal were given by first-principles calculations. The results show that alloy element impurities (Al, Cr and Y) influence remarkably the adhesion of the ceramic and metal. On the other hand, the phonon densities of states and phonon dispersions of ZrO2 were calculated with density functional perturbation theory. From the phonon DOS, the thermodynamic properties were derived and the phase transformation of ZrO2 was discussed. By this method, the thermodynamic properties of material can be gotten from atom and electron levels without any experiment data. It is a new approach to design and study the thermodynamic properties in new material system.

Recent Advances in Semiconductor Nanocluster Preparation

1990 ◽  
Vol 195 ◽  
Author(s):  
A. P. Alivisatos ◽  
V. L. Colvin ◽  
A. N. Goldstein ◽  
M. A. Olshavsky ◽  
J. J. Shiang
Keyword(s):  
Thermodynamic Properties ◽  
Metal Surface ◽  
Semiconductor Nanocrystals ◽  
Organometallic Synthesis ◽  
Size Dependent ◽  
Cds Nanocrystals ◽  
Recent Advances ◽  
Potential Applications ◽  
Nanocrystalline Semiconductor

Semiconductor nanocrystals have received an extraordinary degree of attention during thepast few years. The electronic, optical, photochemical, and thermodynamic properties of these materials are strongly size dependent, providing a rich area of research, with many potential applications1. It remains true that the range of phenomena that can be studied in nanocrystals is limited by the quality of available samples. In this paper we describe two advances in the preparation of nanocrystalline semiconductor samples. First is the preparation of CdS nanocrystals covalently bound to a metal surface; in this configuration it is possible to study the nanocrystals by photoemission. Second, we report the organometallic synthesis of GaAs nanocrystals.

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