Number of analyses

By means of the transform utility, the user is able to perform a great number of analyses without programmer support. The user is also able to display data in whichever units are appropriate without programmer intervention. 

Figure 1.33. Frequency (number of analyses) histogram for Fc203 (wt%) of epidote from the Kuroko basalt. A epidote coexisting with albite, B epidote coexisting with chlorite, C epidote coexisting with pyrite, D epidote coexisting with hematite and calcite (Shikazono et al., 1995).

Figure 1.70. Ag content (atomic fraction of Ag) of electrum from the Te-type and Se-type deposits (Shikazono et al., 1990). rr. number of analyses.

Figure 1.174. Frequency (number of analyses) histogram for Ag (atomic %) of gold from the Tsugu deposit (solid) and epithermal gold-silver vein-type deposits in Japan (open). I sample I II sample II. Data sources Tsugu deposit (Shikazono and Shimizu, 1988b) epithermal gold-silver vein-type deposits in Japan (Shikazono 1981, 1986 Shikazono and Shimizu, 1988b).

Figure 1.187. Frequency (number of analyses) histogram of FeS content (mol %) of sphalerite from auriferous vein deposits in Japan (Shikazono and Shimizu, 1987).

Chemical composition of selected mineral assemblages from midocean ridge sulfide deposits (Hannington et al.. 1995). N number of analyses... 

In the development of analytical methods one has to consider also cases where a fast response is required, e.g. clinical and forensic chemists or toxicologists need methods which yield results in a few minutes or hours to allow a fast response in cases of poisoning. In this event, accurate quantitative results may be of less importance, but the time from sampling to result may be lifesaving, whereas the throughput (i.e. number of analyses per day) is not so much of concern. 

Verification implies that the laboratory investigates trueness and precision in particular. Elements which should be included in a full validation of an analytical method are specificity, calibration curve, precision between laboratories and/or precision within laboratories, trueness, measuring range, LOD, LOQ, robustness and sensitivity. The numbers of analyses required by the NMKL standard and the criteria for the adoption of quantitative methods are summarized in Table 10. 

The annual cost of the laboratory analyses required for process monitoring and quality control is a significant item in most modem chemical plants. The costs should be calculated from an estimate of the number of analyses required and the standard charge for each analysis, based on experience with similar processes. 

A permanent setup has been made to expedite the handling of a large number of analyses (3). 

Furthermore, it is sometimes questionable to use literature data for modeling purposes, as small variations in process parameters, reactor hydrodynamics, and analytical equipment limitations could skew selectivity results. To obtain a full product spectrum from an FT process, a few analyses need to be added together to form a complete picture. This normally involves analysis of the tail gas, water, oil, and wax fractions, which need to be combined in the correct ratio (calculated from the drainings of the respective phases) to construct a true product spectrum. Reducing the number of analyses to completely describe the product spectrum is one obvious way to minimize small errors compounding into large variations in... 

In the adsorption with Tenax alone satisfactory results were obtained, while in the presence of mineral oil a considerable proportion of the organophos-phorus pesticides (particularly Malathion and Parathion-methyl) was not adsorbed and was recovered in the filtered water. This drawback can be overcome by adding a layer of Celite 545 which, in order to prevent blocking of the column, is mixed with silanised glass wool plugs. A number of analyses of surface and estuarine sea waters were carried out by this modified Tenax column and simultaneously by the liquid-liquid extraction technique. To some of the samples taken, standard mixtures of pesticides were also added, each at the level of 1 xg/l (i.e., in concentration from 13 to 500 times higher than that usually found in the waters analysed). One recovery trial also specifically concerned polychlorobiphenyls. The results obtained in these tests show that the two extraction methods, when applied to surface waters that were not filtered before extraction, yielded very similar results for many insecticides, with the exception of compounds of the DDT series, for which discordant results were frequently obtained. 

In addition to the detailed checking of procedures, as set out in the check-list, audit trails are particularly valuable. This is a vertical audit and refers to the examination, in chronological order, of all records relating to a particular sample, from the moment of receipt through the various analyses carried out, to the reporting of results and the ultimate disposal of the sample. These vertical audits are therefore also sometimes referred to as birth-to-death audits. In contrast, a horizontal audit covers some specific activity across a number of analyses - this may be, e.g. solid-phase extraction or HPLC. 

The cost per sample decreases when you have a number of analyses of the same type. 

The complexity of a sample matrix increases if the sample is derived from a biological system. Note that the number of analyses per compound dramatically increases as the complexity of determining compound properties increases, while the number of individual compounds decreases by filtering out unsuitable structures. At the end of a clinical trial phase, perhaps 100,000 LC/MS analyses may have been performed for one compound (Figure 3.2). 

Column Diameter (urn) Solvent Consumption per Run (uL)a Number of Analyses per 100 mL Solvent... 

For nano LC using a 75 /im ID column, 100 ml of solvent can handle more than 16,000 injections (2-min analysis time per injection). No solvent waste collects because it is evaporated. Conventional LC will produce more than 320,000 ml of solvent waste for the same number of analyses. 

A summary of the analyses of these five instruments is given in Table 6.5. The figure in brackets gives the total number of separate parts of the instrument analysed (the denominator), and the number of analyses included in the average figure (the numerator). 

Fatty acids have been reported in a large number of analyses of archaeological residues. They are often associated with cooking vessels (Charters et al. 1993), lamps (Evershed et al. 1997b), or transport vessels... 

Isotachoelectrophoresis or capillary column isotachoelectrophoresis has been employed in a number of analyses (triazine, herbicides, paraquat, diquat, growth regulators, polyaromatic hydrocarbons, polychlorobiphenyls and tetrahydrothiophene). 

This technique has been established for many years particularly for water, soil and feeding-stuff analysis, where a large number of analyses are required for quality control or monitoring purposes. A number of applications have been published for food additives including aspartame (Fatibello et al., 1999), citric acid (Prodromidis et al., 1997), chloride, nitrite and nitrate (Ferreira et al., 1996), cyclamates (Cabero et al., 1999), sulphites (Huang et al., 1999 AOAC Int, 2000), and carbonate, sulphite and acetate (Shi et al., 1996). Yebra-Biumm (2000) reviewed the determination of artificial sweeteners (saccharin, aspartame and cyclamate) by flow injection. 

A number of analyses have pointed out the functional relations between genes that occur in clusters on the genome (see Section III,B). 

Note uncertainties are those listed in the cited source or recalculated from data therein, 2a population, where available number in parentheses is number of analyses factored into this precision, where given... 

Figure 3. Histogram of 5 C1 in groundwater and formation water brines from sedimentary basins and oil fields relative to Cl/ Cl in SMOC (vertical dashed line at 0%o). N is the number of analyses, and bracketed numbers identify references as follows [1] Kaufmann et al. 1993 [2] Eggenkamp 1994 [3] Ziegleret al. 2001 [4] Eastoe et al. 2001 [5] Kaufmann 1984 [6] Kaufmann et al. 1984 [7] Kaufmann et al. 1988 [8] Eastoe and Guilbert 1992 [9] Eastoe et al. 1999 [10] Desauliniers et al. 1986 and [11] Eggenkamp et al. 1994.

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