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Abstract  

A statistical technique based on the Wilcockson criterion is suggested for estimation of the reproducibility of thermoanalytical experiments. Reduction of the whole physicochemical process to a quasi-one-stage process is described.

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Abstract  

Yagi et al recently have claimed that neutrons from the D+D reaction are emitted in Ti and in SiO2 systems in which D2 is trapped at 1 atm at liquid nitrogen temperature. A statistical analysis of the data shows that the background counts observed over 58 time intervals do not follow the expected Poisson distribution. This would invalidate the interpretation of the results.

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/v) (solvent A) and in acetonitrile (solvent B), 0.1% formic acid, v/v), and an optimized gradient elution program from 7% to 40% of solvent B over 50 min with a flow rate of 1.0 mL/min. Data processing and multivariate statistical analysis Unsupervised PCA and

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the differences of all medicinal parts of T. asiatica , the obtained data were statistically processed by multivariate statistical analysis including bivariate analysis, hierarchical clustering analysis (HCA) and principal component analysis (PCA

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renowned academic rankings of world universities along with rankings specifically tailored for Italian universities. We then propose some new evaluation approaches and provide a statistical analysis of the correlation between rankings for Italian

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Abstract  

In the leaves of the medicinal plant Eucalyptus camaldulensis Dehnh (E. rostratus Schlecht) collected from different sampling areas of Greece the trace elements antimony, cesium, chromium, cobalt, iron, europium, rubidium, scandium, strontium, thorium and zinc were determined by Instrumental Neutron Activation Analysis. In the same samples, the essential oil was determined by steam distillation and the percent relative composition of the essential oil in 1,8-cineole, p-cymene, -pinene by gas liquid chromatography. Also the refractive index of the essential oil was determined by a refractometer. Statistical analysis included the calculation of the correlation coefficient. Multiple correlation and cluster analysis was applied to all analytical data. The results showed that the trace elements iron, chromium, cobalt and zinc are correlated with the variation of the concentration of essential oil in the examined plant. These four elements along with rubidium and essential oil content could be used for the separation of the samples into groups related to the sampling areas. Statistically significant correlation between active constituents and some trace elements and a linear negative correlation between 1,8-cineole and refractive index were found.

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Abstract  

Reproducible specific heat capacities (C p) of triglycerides can be obtained by using heat-flux DSC under improved operating conditions. The improved operating parameters, such as the scanning rate, the sample mass and the atmosphere within the DSC chamber, were established via statistical analysis of the experimental data with trilaurin as a sample. The specific heat capacity results on trilaurin were compared with the values calculated by using estimation methods. The precision of the specific heat capacity measured for trilaurin under these conditions was within ±1%.

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Organic wines produced by using organically cultivated grapes were evaluated using multivariate analysis and profiled by quantitative descriptive analysis. Trained judges rated the intensity of aroma and flavour descriptors. The statistical evaluation of the data demonstrated the close relation between Merlot and Cabernet sauvignon wines, considering their aroma descriptors and between Merlot and Carignan taking into account the taste descriptors. Significant differences among white wines were determined for sweet and bitter attributes and among red wines for sour, sweet, bitter, and astringency descriptors. The results of wine aroma characteristics demonstrated the following major descriptors for each wine type: metallic (Columbard); grape juice, wet wood, vine leaf (Semillon); burned wood (Grenache); dust, sour cherry, tobacco, yeast (Cabernet sauvignon); cork, unripe fruit, cinnamon (Carignan); grape molasses, dry plum (Merlot). Flavor profile of organic wines revealed specific descriptors for each wine type, namely raisin (Columbard); alcohol, rose, vine leaf, sulphur (Semillon); clove, salty (Grenache); flower, sour cherry, melon, cornelian cherry (Cabernet sauvignon), dry plum (Carignan, Merlot).

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Abstract  

Neutron activation analysis, in combination with multivariate analysis of the generated data, was used for the chemical characterization of prehistoric pottery from the Greek islands of Thera, Melos (islands with similar geology) and Crete. The statistical procedure which proved that Theran pottery could be distinguishable from Melian, is described. This discrimination, attained for the first time, was mainly based on the concentrations of the trace elements Sm, Yb, Lu and Cr. Also, Cretan imports to both Thera and Melos were clearly separable from local wares.

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