Sampling emulsion measurement

For the reasons described above, the droplet size distribution of the same emulsion measured on different laser diffraction instruments can be significantly different, depending on the precise design of the optical system and the mathematical theory used to interpret the diffraction pattern. It should be noted, however, that the most common source of error in particle size analysis is incorrect operation of the instrument by the user. Common sources of user error are introduction of air bubbles into the sample, use of the wrong refractive index, insufficient dilution of emulsion to prevent multiple scattering. and use of an unclean optical system. 

The exterior phase was analyzed for phenylalanine concentration and pH. All sample volumes were recorded and used for mass balance determination. Phenylalanine was measured spectrophotometrically at lmax = 257.5 nm. Changes in interior phase volume were calculated using material balances. All material balances closed to within 2%. Interior phase concentrations were estimated by the use of material balances and exterior phase concentrations. The interior phase components of several representative emulsions were measured by analyzing the interior phase components after thermally demulsifying the emulsion samples. These measurements agreed with estimates to within 10%. 

The smallest size pipeline loop usually considered for measurements intended for industrial scale-up is lin. (2.54 cm) inside diameter [178]. The results are used to determine laminar versus turbulent flow regimes and as input in flow models [178]. Nasr-El-Din [182,183] reviews the methods used to predict pressure drops across emulsions flowing in pipelines, as well as those used to sample and measure oil and solid concentrations in pipelines. An example of an equation for the prediction of water-in-crude oil (North Sea crude oil) emulsion viscosity is given in Equation (6.48). 

Because the beam monitor allows accurate measurement of the total number of ions that are analyzed, a graded series of exposures (i.e., with varying numbers of ions impinging on the plate) is collected, resulting in the detection of a wide range of concentrations, from matrix elements to trace levels of impurities. In Figure 2, the values of the individual exposures have been replaced with the concentration range that can be expected for a mono-isotopic species just visible on that exposure. In this example, exposures from a known Pt sample have been added to determine the response curve of the emulsion. 

Alkalinity and Lime Content. The whole mud alkalinity test procedure is a titration method which measures the volume of standard acid required to react with the alkaline (basic) materials in an oil mud sample. The alkalinity value is used to calculate the pounds per barrel unreacted excess lime in an oil mud. Excess alkaline materials, such as lime, help to stabilize the emulsion and also neutralize carbon dioxide or hydrogen sulfide acidic gases. 

For example, the parameters g = 0.77, h = 0.94, p = 1.4, and C = 0.158 measured for a polymer sample and compared with the plots in Figures 7.11 through 7.13 were most consistent with athree-arm star monodisperse polymer a poly disperse three-arm star would have g= 1.12,/ = 1.05,p= 1.6, and C close to 0.2. °° The second example was poly(vinyl acetate) (PVAc) prepared by emulsion polymerization. Since no data for linear equivalent were available, g and h were not calculated. At lower conversion/MW p= 1.84 was found, only slightly higher than the theoretically expected p = 1.73 for a randomly branched architecture, p slightly decreased with increasing M, indicating... 

Cherry and Crandall in 1932 (86) used olive oil as substrate with gum acacia as the emufsTfier. This method has served as the basis for a number of modifications that increased the stability of the emulsion, decreased incubation time and gave better precision. When a serum sample is incubated with a stabilized olive oil emulsion, lipase acts at the interface of substrate and water to hydrolyze olive oil into fatty acid plus diglycerides, and to a small extent to monoglycerides and glycerol. The bile salt sodium deoxycholate activates the reaction. These methods measure the liberated fatty acids by titration with a standardized NaOH solution. An indicator such as phenolphatalein, thymolphthalein or methyl red or a pH meter are used to detect the end point. 

In the foregoing we loosely talked about the intensity of a sensory attribute for a given sample, as if the assessors perceive a single (scalar) response. In reality, perception is a dynamic process, and a very complex one. For example, when a food product is taken in the mouth, the product disintegrates, emulsions are broken, flavours are released and transported from the mouth to the olfactory (smell) receptors in the nose. The measurement of these processes, analyzing and interpreting the results and, eventually, their control is of importance to the food... 

You are asked to measure the viscosity of an emulsion, so you use a tube flow viscometer similar to that illustrated in Fig. 3-4, with the container open to the atmosphere. The length of the tube is 10 cm, its diameter is 2mm, and the diameter of the container is 3 in. When the level of the sample is 10 cm above the bottom of the container the emulsion drains through the tube at a rate of 12cm3/min, and when the level is 20 cm the flow rate is 30 cm3/min. The emulsion density is 1.3 g/cm3. 

The shake-flask method has some drawbacks, however. One problem that occurs occasionally is the formation of micro-emulsions which remain stable for hours or days, and prevent the two solvent layers from separating. In this case it is not possible to measure the concentration of analyte in each phase. More generally, the upper and lower range of log D values is limited by problems of solution handling. For very high log D values the sample is much more soluble in octanol than in water. For example, if log D is 4 the sample is 10,000 times more soluble in octa-... 

A radiochemical method for the determination of Rn-220 in fumarolic gas is studied. Both condensed water and non-condensing gas are collected together and Pb-212 is precipitated as PbS. After dissolving the precipitate in conc.HCI, it is mixed with an emulsion scintillator solution for activity measurements. As Pb-214 is simultaneously measured, the observed ratio of Pb-212 /Pb-214 gives Rn-220/Rn-222. This method is superior to the method of directly measuring Rn-220 for the samples in which Rn-220/Rn-222 ratios are less than unity. This method and the previously proposed direct method were applied in the field, and new data obtained. An attempt was also made to understand the formation and transport of radon underground. 

Formation and transport of radon ) In the present work, lead isotopes were chemically separated from the sample gas as lead sulfide since the formation of lead sulfide was inevitable under the presence of H2S in the fumarolic gas. The lead sulfide was then dissolved in a small amount of concentrated HCI and mixed with the Insta Gel(emulsion scintillator solution, Insta Gel, Packard Inc.) for the liquid scintillation counting. The chemical yield and the volume of the collected non-condensing gas were obtained from the measurement of the activities of Pb-214 and its progeny which were in radioequilibrium with their precursor Rn-222 whose concentration was determined separately by the direct method. 

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