Scoop sampling

General Methods. Sampling with a suitable device (beaker, sampling scoop) is applicable for solid materials, especially pigments, fillers, and resins in powder, granular, or lump form. For standards, see Table 1 ( Sampling ). 

Despite the potential advantages of the procedure, sampling coal in motion may suffer from disadvantages such as (1) it is not always possible to penetrate the full depth of the coal cascading out of the car (2) attempts to penetrate the stream result in sample scoop overflow (3) increment collection is limited to the exposed surface at the sides of the car (4) moisture is often higher at the sides of the car than for the entire contents of the car (5) flow rates are highly variable and (6) disproportionate amounts of coarse coal are often collected because the coarse particles segregate and roll down the exposed surface. 

Collect a soil sample into a glass jar using a disposable sampling scoop or a decontaminated stainless steel spatula. Remove stones, twigs, grass, and other extraneous material. Fill the jar to the top with firmly packed soil. 

McBain reports the following microtome data for a phenol solution. A solution of 5 g of phenol in 1000 g of water was skimmed the area skimmed was 310 cm and a 3.2-g sample was obtained. An interferometer measurement showed a difference of 1.2 divisions between the bulk and the scooped-up solution, where one division corresponded to 2.1 X 10 g phenol per gram of water concentration difference. Also, for 0.05, 0.127, and 0.268M solutions of phenol at 20°C, the respective surface tensions were 67.7, 60.1, and 51.6 dyn/cm. Calculate the surface excess Fj from (a) the microtome data, (b) for the same concentration but using the surface tension data, and (c) for a horizontally oriented monolayer of phenol (making a reasonable assumption as to its cross-sectional area). 

Sediments from the bottom of streams, rivers, lakes, estuaries, and oceans are collected with a bottom grab sampler or with a corer. Grab samplers are equipped with a pair of jaws that close when they contact the sediment, scooping up sediment in the process (Figure 7.5). Their principal advantages are ease of use and the ability to collect a large sample. 

Schdpf-gefass, n. scoop, dipper, ladle, bucket, -herd, m. casting crucible (of a furnace), -kelle, /., -ISffel, m. scoop, ladle, -papier, n. handmade paper, -probe, /. drawn (dipped, ladled) sample ladle test, cup test, -rad, n. bucket wheel, -rahmen, m. Paper) deckle. 

If a watch glass is employed for weighing out the sample, the contents are transferred as completely as possible to the funnel, and then a wash bottle is used to remove the last traces of the substance from the watch glass. If the weighing scoop (Fig. 3.8 Section 3.25) is used, then of course a funnel is not needed provided that the flask is of such a size that the end of the scoop is an easy fit in the neck. 

Areal Variation. One objective of the sampling comparison studies was to determine the variation in TCDD concentration over a small area to estimate the error associated with a grab sample concentration. Accordingly, a one-square-yard area was selected adjacent to a previously sprayed road. The center of the test area was about 6 feet from a sprayed road shoulder. This one-square-yard area was divided into nine one-square-foot areas. Using clean spoons and knives, a single scoop was collected from the center of each one-square-foot area down to a depth of 2 inches. The data are presented in Figure 1. 

The designation (aq) indicates a water solution. (Three other chemical states and their formula notations include liquid [1], solid [s], and gas [g].) The substance is in a solution, which is defined as a homogenous mixture of two or more substances. Homogenous means that the solution has a uniform chemical makeup. In other words, if you took samples of a solution from two different areas of its container, the two samples would look the same and have the same chemical composition, as would, say, two spoon-0 fills of vanilla ice cream scooped from different parts of the same... 

Other matrices or chemical systems that come into contact with a sample include the sample container, spatulas, scoops, grinders, mixers, filters, etc. Precautions should be taken to assure that these do not unintentionally affect or alter the composition of the sample in any way. 

Sampling units may be as simple as a piece of chemically treated paper used to swipe a surface or one with multiple parts such as pumps, valves, scoops, and heating units. It may be physically integrated into the rest of the system or operated separately, as in the case of the swipe paper. 

If there is a spatial distribution of the attribute of interest, this method is prone to error and potentially significant errors. Scoop sampling is a nonprobabilistic method... 

There are many laboratory devices available for the reduction of the primary sample to an analysis sample. The three most important methods used in the pharmaceutical industry are (i) scoop sampling, (ii) cone and quartering, and (iii) the spinning riffler or rotary sample divider (Fig. A-3). 

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