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Blank runs

Blank runs on the reagents should be carried through all the operations, and corrections made, if necessary. [Pg.416]

In order to eliminate the possibility that the observed FRC signal was due to diffusion effects or other experimental artifacts, two types of blank runs were performed with each catalyst. In one set of experiments, Ife was used as the "adsorbing" gas with a reduced catalyst while in a second set, H2 was used with a non-reduced catalyst. Neither type or experimental led to any observable FRC signal. [Pg.70]

The results were corrected by subtracting the amount of thiosulfate used for the blank run parallel with each determination. [Pg.204]

The non catalytic blank run carried out at 70°C of the 0.01M phenol - 0.1M HP solution showed that no reagent degradation occurs without a catalyst at the selected reaction... [Pg.419]

Figure 19.9 Conjugation of the biological peptide [Met5]-enkephalin to BSA using EDC. The graph shows the gel filtration profile (on Sephadex G-25) after completion of the conjugation reaction. A blank run with no added EDC was done to illustrate the peak absorbance that would be obtained if no conjugation took place. With addition of 10 mg of EDC to a reaction mixture consisting of 2 mg of BSA plus 2 mg of peptide, nearly complete conjugate formation was obtained. Figure 19.9 Conjugation of the biological peptide [Met5]-enkephalin to BSA using EDC. The graph shows the gel filtration profile (on Sephadex G-25) after completion of the conjugation reaction. A blank run with no added EDC was done to illustrate the peak absorbance that would be obtained if no conjugation took place. With addition of 10 mg of EDC to a reaction mixture consisting of 2 mg of BSA plus 2 mg of peptide, nearly complete conjugate formation was obtained.
FIGURE 3.10 Development of column backpressure when a series of incompletely equilibrating methods are applied (illustration). After an initial phase of blank runs, the pressure curve shows a continuous pattern (illustration). [Pg.109]

Procedure Transfer an accurately measured volume of about 30.0 ml of 0.1 N potassium bromate solution into a 250 ml iodine flask. Add to it 3.0 g potassium iodide, followed by 3.0 ml of potassium iodide, followed by 3.0 ml of hydrochloric acid. Mix the contents thoroughly and allow it to stand for 5 minutes with its stopper in position. Titrate the liberated iodine with previously standardized 0.1 N sodium thiosulphate, using 3.0 ml of freshly prepared starch solution as an indicator at the end-point. Carry out a blank run using the same quantities of the reagents and incorporate the necessary corrections, if any. Each ml of 0.1 N sodium thiosulphate is equivalent to 0.002784 g of KBr03. [Pg.217]

TPD-NH3 curves were obtained in a temperature range of 120 to 600°C, at a rate of 15°C/min. The adsorption of ammonia onto the sample was carried out at 25°C. Subsequently, the removal of ammonia was performed at 500 or 550°C for 1 h by purging air or pure nitrogen. Blank runs were carried out under the same conditions but with no NH3 adsorbed. The TPD-NH3 curves were obtained after subtraction of the blank run. [Pg.75]

FIGURE 5 Schematic representation of the mechanism for enantiomeric separation in chiral CE of basic compounds with cyciodextrin type selectors. The model electropherograms represent I blank run with buffer electrolyte at acidic pH 2 sample run with buffer electrolyte at acidic pH, no enantiomeric separation is observed 3 blank run with background electrolyte including a selector, e.g., cyciodextrin. Note a small delay in the EOF zone and 4 sample run with background electrolyte containing a selector, e.g., cyciodextrin, resulting in enantiomeric separation of the peaks. [Pg.75]

In the first series of experiments toluene was used as the solvent and the extractions were carried out at a temperature of 110°C. The ratio of extract to toluene was varied and a blank run was also carried out with no toluene added. This was to make certain that no precipitation was occurring as a result of cooling and reheating. [Pg.255]

The effects of mercury compression and the compressive heating of the hydraulic oil are thermodynamically compensated. Therefore, the need to make blank runs is unnecessary for all but the most exacting analysis. Blank runs made on cells filled with mercury show less than 1 % of full-scale signal over the entire operating range from 0 to 60000psi. [Pg.210]

Traces of ethylene glycol have been detected in catalytic solutions derived from Ru3(CO),2 in THF solvent, after reaction at pressures of 1000-1500 atm (176) a blank run containing no Ru3(CO)12 immediately preceding these experiments produced no detectable glycol. The major products of these ruthenium-catalyzed experiments were found to be methanol and methyl formate. [Pg.377]

V = Ml of Na thiosulfate soln required for the blank run concurrently with the synthetic proplnt mixture v = M1 of Na thiosulfate soln required for the synthetic proplnt sample This procedure, also described by Pierson (Ref 4, p 1382), is a modification of that given by Butts et al (Ref 1)... [Pg.147]

Use of the resins with samples containing free chlorine residual is not recommended. Cheh (35) suggested that chlorine may produce mutagenic artifacts on XAD-4. Our experiment with 2-mg/L chlorine residual appeared to promote the release of irreversibly adsorbed spiked standards Six model compounds were recovered at levels several times higher than those observed in normal blank runs. In addition, many resin artifacts were eluted after exposure to this chlorine level, primarily aromatic and aliphatic acids, aldehydes, and ketones. Stoichiometric dechlorination (ferrous ion) is therefore recommended in order to avoid cross contamination between samples and inclusion of undesirable resin artifacts in the residue to be bioassayed. [Pg.553]

Figure 6.12. Blank run using a wel1-conditioned silicone column and a white septum. A new septum was inserted 30 min before each programmed run was made. Programmed from 30 to 200°C at 8°C/min. Detector temperature 350 C. Injection port 400°C. FID range 10. Attenuation 16. Figure 6.12. Blank run using a wel1-conditioned silicone column and a white septum. A new septum was inserted 30 min before each programmed run was made. Programmed from 30 to 200°C at 8°C/min. Detector temperature 350 C. Injection port 400°C. FID range 10. Attenuation 16.
For aroma extracts, the blank sample is a mixture of the solvents used in the extraction, and are concentrated in the same way as the aroma isolate. Some volatiles in aroma extracts may derive from trace impurities of the solvents. For headspace techniques, a blank run is also recommended to check impurities coming from the tubings and/or adsorbents used. [Pg.1014]


See other pages where Blank runs is mentioned: [Pg.745]    [Pg.497]    [Pg.286]    [Pg.359]    [Pg.83]    [Pg.31]    [Pg.418]    [Pg.757]    [Pg.185]    [Pg.147]    [Pg.109]    [Pg.76]    [Pg.207]    [Pg.113]    [Pg.169]    [Pg.411]    [Pg.149]    [Pg.284]    [Pg.293]    [Pg.294]    [Pg.15]    [Pg.177]    [Pg.483]    [Pg.221]    [Pg.222]    [Pg.72]    [Pg.290]    [Pg.1622]    [Pg.1092]    [Pg.1093]    [Pg.453]    [Pg.322]    [Pg.393]   
See also in sourсe #XX -- [ Pg.54 ]




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Blank

Blank run approach

Blank, blanking

Blanking

Running

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