Experimental procedure compositional analysis

The experimental procedure for conducting phase solubility analysis is rather simple it consists of mixing increasing amounts of sample with a fixed volume of solvent and then determining the mass of sample that has dissolved after each addition. It is not necessary to exceed the solubility limit of the analyte species, but attainment of this condition makes it easier to recognize trend within the plots. An experimental protocol for phase solubility analyses is available [39]. The data are most commonly plotted with the system composition (total mass of sample added per gram solvent) on the x axis, and the solution composition (mass of solute actually dissolved per gram of solvent) on the y axis. 

The dye-clay composites were prepared by dispersing the clays in each solvent containing the dye at a quantity of 10-200% of the CEC. This experimental procedure led to almost complete intercalation at room temperature for 2-7 days. The composite was recovered by filtration and washing several times with each solvent for eliminating an excess of dye, and then dried in air. Assuming that the loss of dye adsorbed on the surface was fairly small upon washing, the net weight of dye intercalated was estimated from the residual dye concentration in a solvent measured by a colorimetric analysis. 

The current study was aimed at generalization of the procedure for the quantitative composition determination for hexagonal/lamellar mixed phases using adsorption isotherms. Recent advances in adsorption on calcined MCM-41 silicas [29-31] made it possible to construct model adsorption isotherms for these materials with arbitrarily chosen pore sizes (or equivalently, capillary condensation pressures). Such model adsorption isotherms can be used instead of experimental adsorption isotherms for pure MCM-41 materials of the required pore size, significantly extending the range of HL materials, for which the phase composition analysis can conveniently be carried out on the basis of gas adsorption data. 

Several experimental procedures can be used to measure the residual stresses. The three preferred methods involve diffraction (X-ray or neutron), beam deflection, and permanent strain determination. X-ray diffraction measurements have the limitation that the penetration depth is small, such that only near-surface information is obtained. Moreover, in composites, residual stresses are redistributed near surfaces.47 Consequently, a full stress analysis is needed to relate the measured strains to either q or a. ... 

Quantitative y-ray spectrum analysis of environmental samples such as soil, water or ash of food requires the peak efficiency for volume sample. A Marinelli beaker is often used as a container for a large quantity of sample such as water or soil. As the volume of sample to be measured is usually fixed, the absolute peak efficiency is dependent on energy only, but affected by self-absorption which depends on density of matrix and the elemental composition. The method to be used for determination of the peak efficiency is based on experimental procedures involving the following steps ... 

Pentachlorophenyl acrylate, (1), was terpolymerized with methyl methacrylate (MMA) and n-butyl acrylate (nBA) (Scheme III) to give a latex containing 537 solids and a pll of 4.7 which was adjusted to 6.8 by adding aqueous NaOH. The latex was stable up to pH =10. A small aliquot vzas coagulated and the resulting polymer purified. Its intrinsic viscosity was 3.1 /g and analysis indicated 2 mole percent (1), 587 CIA and 40" nBA. Similar terpolyner latices were prepared from acrylates (2) and (3) (Scheme III). Another terpolymer latex made from (3), vinyl acetate, and 2-ethylhexyl acrylate contained 547 solids. Tliese latices and their compositions are summarized in the Table 1 and a sample experimental procedure is given in the experimental section. 

The most common experimental procedure for establishing rate equations is to measure the composition of the reaction mixture at various stages during the course of reaction In a batch system this means analysis at various times after the reaction beginsT Then the data are compared with various types of rate equations to find the one giving the best agreement. The comparison can be made in two ways ... 

The composition analysis results of several Chinese ARO are shown in Table 1. This experimental procedure is outlined in Fig, 3. 

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