Boxes representative sample

Stored Free-Flowing Material. It is practicahy impossible to representatively sample stationary free-flowing powder because of the severe segregation that has almost certainly occurred. If there is no alternative but to sample this material, several samples should be taken and analyzed separately, so that an estimate can be made of the rehabhity of the measured parameter. For free-flowing materials stored in small hoppers, dmms, cans, boxes, and... 

FIGURE 7.7 A tiny sample of solid carbon monoxide consisting of foui molecules. Each box represents a different arrangement of the four molecules. When there is only one way of arranging the four molecules so that they all point in one direction (as in the top left image), the entropy of the solid is zero. When all sixteen ways of arranging four CO molecules arc accessible, the entropy of the solid is greater than zero. 

Figure 2.3. Carbon and nitrogen isotope values of human bone collagen at Maya sites in Belize. The value for the modem sample has been corrected for collagen-hair spacing and the Industrial Effect. Boxes represent isotopic means one standard deviation.

Fig. 38. A Degradation experiments with pregel polymers isolated prior to the onset of macrogelation in 1,4-DVB polymerization [209] Variation of Mw ( ) and dz (O) with the time of ultrasonic degradation. The polymer sample was prepared at 5 g/100 mL monomer concentration and its initial Mw was 2.2 X106 g/mol. The dotted horizontal line shows Mw of zero conversion polymers ( individual microgels ). B Variation of Mw with the polymerization time t and monomer conversion x in 1,4-DVB polymerization at 5 g/100 mL monomer concentration. The region 1 in the box represents the limiting Mw reached by degradation experiments. [Reprinted with permission from Ref. 209,Copyright 1995, American Chemical Society].

Another graphical description of the data is used when comparing the results of several trials is the box plot (also called box-and-whisker plot). A box represents the range of the middle 50% of the data, and whiskers extend to the maximum and minimum values. A line is drawn at the median value. A glance a this plot allows one to assess the symmetry and spread of the data. Figure 5.4 is a box plot for the carbonate data of figure 5.2. Specific plots, such as Youden two-sample plots for method performance studies, are discussed below. 

Figure 5 Sample database schema. A database schema shows the types and nature of links between different types of data. Each box represents a table within the database. The rows within that box correspond to the fields of the table. The lines connecting the boxes identify the required relationships amongst the different types of data stored in the different tables.

Figure 1 Depth profile of radon loss fraction. Filled circles and error bars represent the mean and standard error of the radon loss fraction from all samples from the indicated depth for which the Cs/ Ra ratio is less than 0.05. The boxes represent 1 a deviation and the whiskers the extreme values of each population. The number of samples is given in the column on the right. The curve corresponds to Equation (1) with an emanating power of 0.28 and...

Figure 8. 3D cross-sectional view of the central portion of the Ozark Uplift. Inset box shows the areal extent of the 3D model and view direction. View is looking to the east, down the axial crest of the Ozark uplift. Surfaces of the model are the tops of the regional aquifer units of the Ozark aquifer system. Vertical exaggeration is approximately 40X. The vertical lines within the model are the locations of CUSMAP boreholes (also shown in Fig. 3). The enlarged red blocks are chemical analyses of insoluble residue samples that contain greater than 700 ppm arsenic (approximately equal to 70 ppm on a whole rock basis), in contrast to the small black boxes that represent samples with less than 700 ppm.

Figure 6. Box plots of concentrations of selected constituents. Plots show the 25 and 75 percentiles as end-tines. Mid-line of the box represents 5tf percentile, and capped bars indicate Kf and PC percentiles. Circles mark 5 and 95 percentiles. The mean value is shown as a dotted line. A, B, C, and D refer to four water types non-impacted, low, moderate and high arsenic, respectively. Number of samples in parentheses. Data from WDNR (2001, unpublished).

The analytical process comprises three main steps, which can be represented as shown in Figure 7.1. As can be seen, there are two primary time-consuming steps the input and the output. The black box represents the measurement of the analytical information it needs half the time that is required by the input or output steps.3 The input step includes sample preparation and is a very difficult step to perform, especially when spectrometric methods are used. The output step includes data processing. The introduction of the computer for data processing improves the quality of the analytical information, as well as the rapidity and reliability of this step. 

Whenever possible, objects should be lifted in a rigid container (not in a bag) and packed with a representative sample of the surrounding matrix to limit movement and damage during recovery. A supply of numbered plastic boxes with attached lids should, like the sandbags, be stored close to the excavation. If surface conditions are severe, the containers, suitably numbered and recorded, can be stored on the bottom until calmer conditions occur. 

Chart I. A representative sampling of good fast dyes. The name of the general chromophore is given in the box above each structure. The common names of the dyes are listed under each structure. 

Sampling of liquid streams for process control and accountability of fuel poses unusual problems because of the radioactivity involved. Landry describes the numerous ingenious sampling devices which are used. Most designs depend on a gas lift to recirculate the liquid to a shielded sampling box where a representative sample is removed. 

FIGURE 10.6 Schematic representation of microchip electrophoresis device designs (a) shows a traditional cross-t design while (b) shows an offset cross-t. The reservoirs are labeled as follows SI is the sample inlet, SO is sample outlet, Bl is buffer inlet, and BO is buffer outlet. A closer view of the cross-t can be seen in the dotted boxes during sample injection and separation the sample is in gray and the + and — represent the position and what type of voltage is being applied. 

In the case of raw carcass meat, another problem is that of obtaining a representative sample. Because the muscles of the animal (the primal cuts) are irregular in shape and in fat content, samples for analysis must be clearly defined in terms of anatomical position. In the case of boxed beef, which is used in meat processing, it is important to have a sample representative of the total content, particularly in terms of lean and fat. 

Fig. 8 Boxplots of PEC concentrations in drinking water (data of 2006) (a) including known hot spot samples and (b) excluding known hot spot samples black dots represent outliers (mostly polluted sites), line within the box represents 50th percentile (median) box delimits 25th and 75th percentiles bars indicate 10th and 90th percentiles results <1 ng/L were taken as 0 ng/L in the calculation [61]...

FIG. 2. Map of experimental variables in this study. Each box represents a s.pecified combination of polymer composition, casting solvent character (6), and polymer molecular weight (M), corresponding to a type of sample which was tested. 

Fig. 11 Overall and polar surface energies measured by the Owens-Wendt technique (with Washburn absorption) for various types of Toray TGP-H paper GDLs. Values in white boxes represent the total aerial loading of PTFE for each sample. AA plain, BA 5 wt% substrate/0 wt% MPL, BC 10 5wt% substrate/10wt% MPL, BC 5wt% substrate/23wt% MPL, DA 20wt% substrate/0 wt% MPL, DC 10 20wt% substrate/10wt% MPL, DC 20wt% substrate/23 wt% MPL...

Fig. 6.6 Determination of the pH of the martian soil (Sorceress 1). Pairs of dashed blue lines represent opening and closing of sample drawCT. Orange line represents addition of calibrant acid. Blue boxes represent intervals used fin the detrmnination of pH before opening of the sample drawer ( LMST 10 35) and after sample delivery ( LMST 12 50). LMST is the local mean solar...

Electron ionization occurs when an electron beam crosses an ion source (box) and interacts with sample molecules that have been vaporized into the source. Where the electrons and sample molecules interact, ions are formed, representing intact sample molecular ions and also fragments produced from them. These molecular and fragment ions compose the mass spectrum, which is a correlation of ion mass and its abundance. El spectra of tens of thousands of substances have been recorded and form the basis of spectral libraries, available either in book form or stored in computer memory banks. 

Natural Deposits. Natural deposits, eg, minerals and fossil fuels, are located by drilling operations. An auger, eg, a screw or worm, is turned in the earth and pulled out, and material is scraped from the auger for analysis. Alternatively, samples can be taken by hoUow core drills which, when withdrawn, enclose a core of the earth that is representative of the strata through which the drill has passed. Such core samples are used in geological surveys for fossil fuels. As the drill drives deeper into the strata, each core is extracted and placed in a shallow box and coded so that a complete cross section of the geological strata can be reconstmcted. From this, the relative thickness of coal and mineral seams can be directly measured. 

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