Homogeneity tests

Fig. 2A. Sampling schemes for bulk analysis (a) and for testing homogeneity of several batches (b), according to Danzer [1995a] and following Horwitz [1990]... 

Data on the enthalpy change, AHd or AHr, established in testing homogeneous samples can be used in the extrapolation to large scale. In the DSC experiments, no pressure data are obtained. 

By analogy with the procedure by DOERFFEL et al. [1988] for testing homogeneity in analytical investigations of solids, the regular raster screen of the investigated area is divided into a meandering shape, i.e. the two-dimensional local series is transformed into a one-dimensional local series. 

Example 8 Testing homogeneity of data. The feed to a reactor is handled by four pumps which have experienced a total of 40 failures during the past year. The distribution of failures per pump is as follows ... 

The last type of precision study is reproducibility (q.v.), which is determined by testing homogeneous samples in multiple laboratories, often as part of interlaboratory crossover studies. The evaluation of reproducibility results often focuses more on measuring bias in results than on determining differences in precision alone. Statistical equivalence is often used as a measure of acceptable interlaboratory results. An alternative, more practical approach is the use of analytical equivalence, in which a range of acceptable results is chosen before the study and used to judge the acceptability of the results obtained from the different laboratories. 

Ahm, 1974Zap] Diffusion couple method Corrosion tests, micro-hardness tests Homogenization degree of sintered of Cr-Cu-Fe alloys with 2 to 18 tnass% Cr and 2 to 4 mass% Cu at 1050 to 1410°C, diffusion coefficient and activation energy of diffusion of Cr in a and -y phases. Microhardness and eorrosion resistance... 

Standard Practice for Testing Homogeneity of Materials for the Development of Reference Materials, ASTM E 826-81, 1981. 

Separation Test Homogeneous from 10C-40C Dilution Test 90% Min., light transmission Color 150 Platinum-Cobalt, Max. 

Normal distribution of the results was verified using the Kolmogorov-Smimov test, homogeneity of variance assessed through the Levene test and differences between groups tested using one-way ANOVA (at a level of 0.05). 

Gaussian curve/distribution Grubbs test Homogeneous Hypergeometric distribution Hypothesis... 

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