Dilution factor

The dissolved oxygen concentrations are determined immediately and after five days. The method for dissolved measurement involves either a modified Winkler titration or a membrane-covered oxygen electrode. The difference between initial and final dissolved oxygen multiphed by the dilution factor is the BOD value. 

The Dilution Factor of the Dyebath. The amount of water in a dyebath may vary from 5—25 times the weight of fiber to be dyed, according to the capacity and type of equipment employed. The larger water-to-fiber ratio dilutes the emulsifier, thus reducing its effect. 

Solutions may typically be analyzed with up to 0.2% dissolved solids. This means a dilution factor of 1000. For example, an element that will give a 0.1 ppb detection limit in deionized water will give a detection limit of 100 ppb in a film dissolved in acid and diluted to 0.1% solids. 

Grignard reagent and dilution factors determine the ratio of the... 

The test sera are available in sealed bottles. Six bottles are used in each test. They are labeled 1, 10" , 10" , 10 , lO", and 10" , indicating the dilution factor. One unit (one ml or one cm ) of the sample solution is collected in a disposable. 

Dilution factor WWTP efiuent-river water... 

Fig. 4 Concentrations (ng L ) of the most ubiquitous analgesics and anti-inflammatories, lipid regulators, psychiatric drugs and [I-blockers detected in (a) wastewater effluents and (b) river water downstream of the three WWTP in the Ebro river basin in relationship to the dilution factor...

FIGURE 3 Effect of the amount of cholesterol on the particle size. Phosphatidylcholine/cholesterol liposomes were prepared by the octyl glucoside dilution technique. The begin concentration of the mixed micelles was 150 mM octyl glucoside and 10 mM phosphatidylcholine in 10 mM tris(hydroxymethyl)aminomethane and 0.9% NaCl, pH 7.4. Dilution was performed with an automatic titration unit at a dilution rate (= dilution factor, relative to the initial volume, per unit of time) of 0.026 sec"l ( a and ) or 0.69 sec l ( and o). Mean diameters after dilution and ) and after filtration ( L and q) are repi sented. (Adapted from Jiskoot et al, 1986a.)... 

The resuits of Exampie and Extra Practice Exercise illustrate an important feature of percent ionization. As the concentration of a weak acid increases, the percent ionization decreases. The concentration of hydronium ion decreases as a weak acid is diluted, but it decreases by a smaller fraction than the dilution factor. This behavior of weak acids played an important role in the development of the ionic view of aqueous solutions, as described in our Chemical Milestones Box. 

Estimate the LOQ using any of the methods described earlier and equate the value in terms of amount in the matrix, factoring in any concentration and dilution factors from the extraction procedure. 

Calculations all dilution factors and calculation parameters should be clearly explained. An example calibration curve should be provided. 

The concentration of analyte in the unknown sample is extrapolated from the calibration curve. To obtain an accurate and precise quantitative value, the optical density (OD) for the sample solutions must fall on the linear portion of the calibration curve. If the sample OD is too high, the sample solution must be diluted until the OD falls within the quantitative range of the assay. The concentration of the analyte in the original sample is calculated by correcting for any dilution factor that was introduced in preparing the sample for application to the microplate. 

Beasley et al. developed a panel of immunoassays to monitor DDT, its metabolites, and structurally related compounds, but they found that milk has a severe effect on the assay performance. They found that when directly utilizing whole milk, color development was completely inhibited. Even when using 1 100 dilutions of whole milk, the assay sensitivity was reduced by 90% (based on the IC50 shift, not simply the dilution factor). A number of procedures were evaluated to eliminate the interferences from the fat-soluble analytes. However, many of the procedures that removed interferences also removed the analytes. Extraction with a mixture of solvents and the use of similarly processed blank milk to prepare the standards ultimately yielded more accurate results. This article demonstrates the difficulties encountered in analyzing lipid-soluble analytes. 

The residue, Wr in mg of an identified analyte is calculated using the sample equivalent Cex from Modules E, the dilution factors Tgpc and Fq from Modules GPC and C, respectively, and the concentration Ca from Modules D. The following equation is used ... 

Calculate the dilution factor Fgpc using the following equation ... 

Note The dilution factor Fqpc is required for calculating the content of an identified analyte according to Section 3.1.5. 

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