Sample range

Automated methods are more rehable and much more precise than the average manual method dependence on the technique of the individual technologist is eliminated. The relative precision, or repeatabiUty, measured by the consistency of the results of repeated analyses performed on the same sample, ranges between 1% and 5% on automated analy2ers. The accuracy of an assay, defined as the closeness of the result or of the mean of repHcate measurements to the tme or expected value (4), is also of importance in clinical medicine. 

Not all cyanobacterial blooms and scums contain detectable levels of toxins. Indeed, the incidence of toxicity detection by mouse bioassay, and toxin detection by HPLC among environmental samples, ranges from about 40% to However, in view of this high occurrence, it is the policy of regulatory authorities and water supply operators in some countries to assume that blooms of cyanobacteria are toxic until tested and found to be otherwise. In the absence of available analytical facilities or expertise or for logistical reasons, this precautionary principle should be regarded as sensible and prudent. 

Mechanical treatment of samples, ranging from comminution by grinding to imposition of stresses along defined crystallographic directions in... 

The effect of carbon chain length and high vs. low 2-phenyl isomer distribution on viscosity and solubility (cloud/clear point) of a liquid hand dishwashing formulation is shown in Table 5. Two sets of pure LAS homolog samples ranging from Cl0 to Cl3 were prepared. All samples were prepared with pure olefins, but one set was produced with an HF alkylation catalyst (low 2-phenyl) and the other set was alkylated with A1C13 (high 2-phenyl). Each LAB... 

Rain samples collected from around the Great Lakes contained both a- and P-endosulfan (Strachan and Huneault 1979). Mean concentrations of a-endosulfan in rain samples from the Great Lakes ranged from 0.1 ng/L (n=13) to 3.8 ng/L (n=16). Mean concentrations of P-endosulfan in rain samples ranged from 1 (n=14) to 12 ng/L (n=16). The endosulfans were not found to any significant extent in snow-core samples (Strachan and Huneault 1979). Detection limits were not reported. 

Total cyanide concentrations in ground water samples ranged from over 300 parts per million (ppm) at the plant site to about 1 5 ppm at a spring located along the banks of the Little Spokane River Wells used for drinking water, irrigation, and livestock purposes contained total cyanide concentrations as high as 23 ppm ... 

Microchemistiy - a branch of analytical chemistry that involves procedures that require handling of very small quantities of materials. Specifically it refers to carrying out various chemical operations (weighing, purification, quantitative and qualitative analysis) on samples ranging from 0.1 to 10 milligrams. (The Condensed Chemical Dictionary 1971). 

The content of mineral substances in honey samples ranges from 0.2 to 10.3 g/kg (White, 1975). Potassium is the main mineral element with an... 

With fortification levels between 0.04 and 0.2 mg kg recoveries from soil samples range from 79 to 104%. The average recovery is 90 6% (n = 19). The LOQ is 0.02mgkg ... 

With fortification levels between 1 and 5 pgkg average recoveries from soil samples range from 83 to 92%. The overall recovery is 88 11 % (n = 19) and the LOQ... 

With fortification levels between 0.01 and 0.61mgkg , recoveries of buprofezin from untreated cucumber samples ranged from 73 to 86%. 

With fortification levels between 0.01 and 1.00mgkg recoveries of BF12 from untreated soil samples ranged from 90 to 97% with the limit of determination being 0.01 mgkg ... 

The fenoxycarb recoveries for orange, onion, grape, and tomato samples ranged from 63 to 70%. The LOQ and LOD were 0.01 mg kg and 0.005 mg kg , respectively, when using liquid chromatography/electrospray ionization mass spectrometry (LC/ESI/MS). 

TABLE 5.9 (continued) Number of Samples/ Range of Mean of... 

The Frio formation, in Texas, receives more hazardous waste by volume through deep-well injection than any other geologic formation in the U.S. The average salinity of this formation is about twice that of seawater (72,185 mg/L TDS), but individual samples range from a low of 10,528 mg/L TDS (barely above the salinity cutoff for potential USDWs) to a high of more than 118,000 mg/L TDS. Data from sites in Illinois and North Carolina indicate the presence of very saline water (around 20,000 mg/L TDS, but still less saline than seawater). 

FIGURE 25.6 Amounts of lutein present (pmole/mm2) in yellow, black, and white epidermal samples from nine individual animals. Each value is the combined result of analysis of between 3 and 8 punches from a single animal providing samples ranging from 0.39 to 1.7 mm2. The absolute detection limit of the HPLC for carotenoids was O.lpmole. The black sample for animal 3 was lost during analysis. 

THM using TMAH has been applied successfully to a variety of samples ranging from natural organic substances to synthetic polymers [43,44], The method is based on the high... 

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