The influence of zirconium ions on the stability of the primary emulsion in model extraction systems was examined. Zirconium ions in the systems containing TBP only cause a slight increase of the stability of the primary emulsions. The addition of MBP brings about precipitation of sediments that fix the emulsions and make phase separation difficult. The addition of DBP increases the stability of the primary emulsion. Kerosene as the diluent of TBP increases the stability of the primary emulsions more than carbon tetrachloride.
Using the nephelometric sedimentation analytical method, the emulsions dispersity was investigated. These emulsions were formed
in a centrifugal extractor mixing chamber with different extraction systems: TBP in kerosene—HNO3 and TBP in CCl4−HNO3. The TBP and HNO3 concentration, the speed of rotation and the supply of the mixing chamber with the phases stream influence on the histeresis
loop of the emulsion type and the emulsion dispersity was described. The foaminess of extraction systems was investigated,
and the stabilizing influence of w/o emulsions on the foaminess was confirmed.
We studied thermal transitions and physical stability
of oil-in-water emulsions containing different milk fat compositions, arising
from anhydrous milk fat alone (AMF) or in mixture (2:1 mass ratio) with a
high melting temperature (AMF–HMT) or a low melting temperature (AMF–LMT)
fraction. Changes in thermal transitions in bulk fat and emulsion samples
were monitored by differential scanning calorimetry (DSC) under controlled
cooling and reheating cycles performed between 50 and –45C (5C
min–1). Comparison between bulk fat samples
and emulsions indicated similar values of melting completion temperature,
whereas initial temperature of fat crystallization (Tonset)
seemed to be differently affected by storage temperature depending on triacylglycerols
(TAG) composition. After storage at 4C, Tonset
values were very similar for emulsified and non-emulsified AMF–HMT blend,
whereas they were lower (by approx. 6C) for emulsions containing AMF
or mixture of AMF–LMT fraction. After storage at –30C, Tonset values of re-crystallization
were higher in emulsion samples than in bulk fat blends, whatever the TAG
fat composition. Light scattering measurements and fluorescence microscopic
observations indicated differences in fat droplet aggregation-coalescence
under freeze-thaw procedure, depending on emulsion fat composition. It appeared
that under quiescent freezing, emulsion containing AMF–LMT fraction
was much less resistant to fat droplet aggregation-coalescence than emulsions
containing AMF or AMF–HMT fraction. Our results indicated the role of
fat droplet liquid-solid content on emulsion stability.
Authors:Robson Miranda da Gama, Tatiana Santana Balogh, Simone França, Tânia Cristina Sá Dias, Valcinir Bedin, André Rolim Baby, Jivaldo do Rosário Matos, and Maria Valéria Robles Velasco
after the use of cosmetics treatments.
This research the effect of oxidative hair dye emulsions, with or without conditioning agents on Caucasian hair. The hair was analyzed by DSC, TG, and Derivative Thermogravimetric (DTG) analysis
, characterization and thermal properties of highly crosslinked, hydrophilic stable spherical microspheres based on the new aromatic tetrafunctional methacrylate monomers and divinylbenzene (DVB) prepared by emulsion–suspension polymerization in the presence of pore
A method is described by which the stability of emulsions can be measured by a modified liquid scintillation counter. The Ra 226 external standard source of a commercially available equipment, fixed in the measuring position, is used for the production of Cerenkov radiation in a sample of an emulsion. This Cerenkov radiation is absorbed by the sample due to its turbidity. The turbidity of emulsions follows a typical course with time designated as creaming-up-curve. These curves can be registrated automatically in digital form.
Authors:Jin-xin Guo, Xuan Sun, Dong-li Du, Xu Wu, Ming-xia Li, Hua Pang, Si-xiu Sun, and Ai-hua Wang
The recovery of uranium(VI) from chloride solution using a liquid emulsion membrane (LEM) technique was studied. The emulsion
is constituted by the quaternary salt of benzyloctadecyldimethyl ammonium chloride (BODMAC, R4NCl) as a carrier, kerosene as organic diluent, Span 80 as emulsifying agent and 0.5 mol/l Na2CO3 as stripping phase. The important variables affecting the LEM permeation process such as the concentrations of extractant,
internal strip phase, types of organic diluent, and the presence of magnesium chloride or magnesium sulfate were investigated.
It was found that, at a given condition, the maximum extraction rate of uranium(VI) reached 80%. The emulsion was stable at
low pH in the presence of certain amounts of electrolytes such as NaCl and MgCl2.
Studies on functional propertiesof a protein concentrate produced from the seeds of bakul (Mimusops elengiL.; Sapotaceae) have been carried out. Solubility of the protein was minimum at pH 4.0. Water and oil holding capacities of the seed protein concentrate were 1.70 g g-1and 3.23 g g-1, respectively. Minimum foaming capacity, minimum emulsifying activity, minimum emulsion stability and maximum foam stability were found at pH 4.0. Moreover, emulsion stability of the protein concentrate was high (above 88.3%) over the pH range of 2-10.
Uranium is extracted by a water-in-oil emulsion consisted from 0.01M 8-hydroxyquinoline /HOx/ in cyclohexane and aqueous solution or Arsenazo III and glycine. Analyzed solution is adjusted to 0.02M 1,2-diaminocyclohexane-N,N,N,N-tetraacetic acid /DCTA/ and pH 7.5±0.1. Preconcentration factor of about 400 can be achieved and when the uranium concentration in the outer solution is above 5 g.dm–3 /5 ppb/ its spectrophotometric determination in the inner solution of the double emulsion system is possible. Thorium practically does not interfere at the ratio Th:U=20:1.