The 1 st Cumulant or moment (a 1) is used to calculate the intensity weighted Z average mean size and the 2 nd moment (a 2) is used to calculate a parameter defined as the polydispersity index (PdI). It is important to note here, that the Cumulants analysis algorithm does not yield a distribution â it gives only the intensity weighted Z average and the polydispersity index.
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The Edexcel International Diploma would typically be completed by the final year of high school. AS and A Levels are at a higher academic level than the high school diploma, and thus university credit may be awarded for A Levels completed as part of the International Diploma by American universities.he Cambridge AICE Diploma would typically be completed by the final year of high school. AS and A Levels are at a higher academic level than the high school diploma, and thus university credit may be awarded for A Levels completed as part of the Cambridge AICE Diploma by American Universities.