Extraction measure

Organic phosphorus is determined by the difference in phosphorus content of the 1M hydrochloric acid extract measured before and after ignition of the dry sediments at 550°C. In all instances the orthophosphate is determined by using standard Technicon AutoAnalyzer II techniques. Silica does not interfere. 

Quite clearly, any measurement of fluid uptake before equilibrium is reached could be misleading. Equally, if there is also extraction, measurement of volume change and other properties should wait until equilibrium, represented by a final plateau condition, is reached. If oxidation or another chemical reaction is taking place an even longer time-... 

Solvent extraction measurements and ultracentrifuge measurements have been reported only in single instances but agreement with other methods has been observed for U0 (N0 ) (Goldberg,... 

Table C2.2.1 Specific Activity Values for a Single Kiwi Fruit Peptidase Extract Measured at Different Enzyme/Protein Concentrations Using Basic Protocol 1...

Figure 10.5 Typical LC-MS/MS trace by negative ESI of isoflavonoids from a urine extract. Measured concentrations in bracket. F-axis units in relative intensity EL = enterolactone, ED = enterodiol, other abbreviations see figure.

The correlations between / and the original features in X, or between g and the original features in Y, are called intra-set loadings. They express the part of the variance which is explained by the canonical variables of its own feature set, and are also called the extraction measures. 

Semenov et al. [8] determined small amounts of petroleum products in chloroform extracts of non saline water by extracting the sample (200-500mL) followed by thin layer chromatography on alumina. He developed the chromatogram with light petroleum-carbon tetrachloride-acetic acid (35 155 1), and examined the plate in ultraviolet radiation the petroleum products exhibit three zones (pale blue, yellow and brown). Each zone is then extracted with chloroform, the fluorescence of the extracts measured and the results referred to a calibration graph. The sensitivity is O.lmg L. The infrared and fluorescence spectra of the zone obtained with various petroleum products are discussed. 

Perez-Jimenez, J. Arranz, S. Tabemero, M. Diaz- Rubio, M.E. Serrano, J. Goni, L Saura-Calixto, F. 2008. Updated methodology to determine antioxidant capacity in plant foods, oils and beverages extraction, measurement and expression of results. Food Res. Int. 41 274-285. 

B. Time-Dependent Solvent Soxhlet Extraction Measurements... 

Two typical sets of potentiometric titration data are presented in Table I, while the data for solvent extraction measurements are given in Table II. Again, an iterative calculation procedure was used to obtain... 

The Fab -functionalized nanotubes were added to racemic mixtures of the SR and RS enantiomers of FTB. The tubes were then collected by hltration and the filtrate was assayed for the presence of the two enantiomers using a chiral HPLC method (Figure 24.5B). Chromatogram I was obtained from a solution that was 20 pM in both enantiomers, and chromatogram II was obtained for the same solution after exposure to the Fab-functionalized nanotubes 75% of the RS enantiomer and none of the SR enantiomer was removed by the nanotubes. When the concentration of the racemic mixture was dropped to 10 pM, all the RS enantiomers were removed (chromatogram III). Nanotubes containing no Fab did not extract measurable quantities of either enantiomer from the 20 pM solution. 

In fluorescence correlation spectroscopy (FCS) a small volume element or a small area) of a sample is illuminated by a laser beam and the autocorrelation function of fluctuations in the fluorescence is determined by photon counting. From this autocorrelation function the mean number densities of the fluorophores and their diffusion coefficients can be extracted. Measurement and analysis of higher order correlation functions of the fluorescence has been shown to yield information concerning aggregation states of fluorophores ). 

The existence of the extracting reagent in the stationary phase is one of the essential factors in the enrichment of inorganic elements as well as in the separation itself. However, the values of the distribution ratios, determined by batch extraction measurements in the two-phase system, is sometimes considerably different from that of the dynamic distribution ratios calculated from the elution curve. Further theoretical and basic investigations are necessarily concerned with extraction kinetics, as well as hydrodynamics behavior of two phases in the high-speed CCC (HSCCC) column [1]. 

We have made equal volume batch extraction measurements on synthetic high sodium concentration waste using 20 volume % DHDECMP in 2 1 decalin-DIPB. Only actinides and a few chemical constituents were examined. Techniques were as described in the above section. Extraction data are shown in Table V. 

Flowsheet Testing. Na2C03 scrub waste solutions were prepared by extracting measured amounts of U(VI) and Pu(IV) into dodecane solutions containing 0.02 M - 0.04 M HDBP and 0.0067 M -0.0134 M H2MBP. The resultant organic phase plus precipitates were then slurried with the required amount of Na2C03 until all the precipitate dissolved. 

Brady et al. (2003) proposed that a site-specific screening approach followed by sequential extraction measurements could be an appropriate method to determine if a contaminated site is suited for MNA. In the first step, the site s chemical and hydrological conditions are assessed from standard site characterization data. The MNAtoolbox (www.sandia.gov/eesector/gs/gc/na/mnahome.html) provides a rapid initial assessment of the chemical and hydrologic conditions for MNA. The site-specific assessment for natural attenuation is then evaluated using sequential extraction experiments that enhance the site s characterization, determine the hioavailability, fate, and transport of the metal(loid)(s) in question, and assess natural attenuation against other remediation options (such as phytoremediation). 

The iodine liberated by thallium(III) may be extraeted into CHCI3 or CCI4 and the absorbance of the extract measured, but this method is much less sensitive than the starch-iodine method. 

The five replicate measurements of the raw extract give an overview of the method s repeatability, the measurements for the within-bottle homogeneity was pierformed in one batch, the between-bottle homogeneity took several days, it can be noted that the within-bottle cv is often smaller than the cv of the extract measurements, but always smaller than the between-bottle cv. The cv obtained from the certification campaign (12 laboratories each using two bottles) is always much larger than this between-bottle cv. 

KANEYUKI T, NODA Y, TRABER M G, MORI A and PACKER L (1999), Supcroxide anion and hydroxyl radical scavenging activities of vegetable extracts measured using electron spin resonance , Biochem Mol Biol Int, 47, 979-989. 

In 1977 Koryta et al. [61] reported the Avalues of several common ions at the NB/W interface, which were calculated from the extraction data using an extra thermodynamic assumption. Afterward, a newly developed electrochemical technique (so-called ion-transfer voltammetry) with a polarizable O/W interface was employed to determine AGtr° w for a variety of ions [33,62-71]. In Table 4 the reliable values of AG ° >w are compiled. Regarding the ions whose AGj r° w values are available for both electrochemical and extraction measurements, the electrochemical data, which seem to be more accurate, have been chosen preferentially. For several ions, somewhat different AGf, 0 w values from electrochemical measurements have been reported, as also seen in the database provided by Girault on a website [72], In this study, however, we have carefully chosen reliable values for the respective ions, which were determined under well-defined conditions (reference electrodes, solution compositions, etc.). 

The distribution coefficients of Pa(V) between nitric acid solutions and solvents containing TBP are less than those of uranium [C6], and are less than those of thorium except at high concentrations of HNO3 [H2]. In extraction measurements it is found that the fraction of Pa(V) that can be extracted decreases with time, due evidently to the slow polymerization of Pa(V) colloids. The more highly condensed forms caimot be depolymetized by acid treatment [K2]. 

Determination of lead on leaves. For each plastic bag containing a leaf sample, heat 20 mL of 0.1 M HNO3 to about 70°C. Add 20 mL to each bag, close, and shake for about 2 min. Pour into clean 100-ml- beakers. Add one drop thymol blue indicator solution to each, followed by dropwise addition of 2 M NH3 until the indicator color change is complete (to blue) and add a couple of extra drops. The solution should smell of ammonia. Then, add only if instructed to) 60 mL of the ammonia-cyanide-sulfite solution—and then add with a pipet 25 mL of the CH2Cl2-dithizone solution and proceed with the extraction measurement as with the standards. 

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