Hitachi F 2500 Manual
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A - 4 (2) Remeasurement of Standards The standards can be remeasured after once preparing a calibration curve. The curve prepared in such case will appear as in Fig. A-4. Fig. A-4 Calibration Curve when Standards are Remeasured STD5 Redrawn calibration curve STD6 STD4 STD3 STD2 STD1 Data Initially measured STD1 CONC Remeasured STD1
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A - 5 APPENDIX B DETAILS OF RATE ANALYSIS FUNCTION B.1 Foreword Rate analysis is used in the analysis of enzyme reactions. It is utilized for clinical and biochemical tests by reagent manufacturers, hospitals and so on. A computer is used to calculate the concentration from the variation in data per unit time, and the result is displayed and printed out. B.2 Calculation Method A timing chart for rate analysis is shown in Fig. B-1. Data is acquired when the initial delay...
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A - 6 Prepare a regression line via least squares method from the measured data, and obtain a determination coefficient. y = ax + b where, a = () xyxy n xx niiii ii−∑ ∑ ∑ −∑ ∑ 22 b = ()yax nii−∑ ∑* x i : Time (sec) of each data y i : Value of each data n : Number of samples The determination coefficient CD becomes as follows : CD = () () }()} { {∑∑∑− ∑ −∑∑∑−2 i 2 i 2 i 2 i2 i i i iy y n x x ny x y x n Gradient (variation per minute) D i = a Tk = 60a (/min) Activity...
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A - 7 APPENDIX C DETERMINATION COEFFICIENT OF CALIBRATION CURVE C.1 Calculation of Determination Coefficient The determination coefficient and other factors are calculated via the following formula. An : Photometric or average value of standards Cn : Concentration on approximation curve versus A Cstdn : Concentration of standard (input value) N : Number of standards DIFF : DIFFn = Cn - Cstdn RD : RD n = DIFF A×100 AA Nn=∑ t : t n = DIFF...
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A - 8 C.2 Usage of Determination Coefficient The determination coefficient indicates the goodness of fit of the measured standards and the prepared calibration curve. The closer this value is to “1”, the better the fit of the measured values and calibration curve. If the value is far from “1”, then the standards must be remeasured or the calibration curve mode must be changed. Examples of determination coefficients upon changing the calibration curve mode are given below....
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A - 9 APPENDIX D INTEGRATION METHOD D.1 Foreword The integration methods used in the FL Solutions program are explained next. D.2 Integration Methods The following three methods are available in the FL Solutions program. Rectangular Trapezoid Romberg The rectangular method is the simplest one among the above three. Since one sampling cycle is equivalent to the width of each sectional area, the total of all data points including peaks approximates the area to be...
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A - 10 This method is a further improvement on peak area calculation. The section of each sampling cycle is indicated by a rectangle on which a triangle is formed. The object area is the sum of all these areas. Fig. D-2 By taking just one rectangle, the area of the rectangular part I r is expressed by the following formula. Fig. D-3 A triangular part is added to this rectangle. Assuming the area of this component is I T and the area of the triangular part is It, we obtain the...
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A - 12 The Romberg method is the most accurate of the three methods discussed here. The trapezoid method provides different step sizes (sampling intervals) for area determination with high accuracy. In this method based on the sum of errors, two different step sizes for individual cases are available. However, unlike the conventional (classic) method of continuous approximation, an arbitrary decrease in step size is not allowed (as in case of an increase in the X-axis direction) for the...
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A - 12 APPENDIX E DESCRIPTION OF FLUOROMETRY E.1 Description of Fluorometry Fig. E-1 Typical Organic Molecular Energy Level Figure E-1 illustrates the energy level transitions in an organic molecule in processes of light absorption and emission. When light strikes an organic molecule in the ground state, it absorbs radiation of certain specific wavelengths to jump to an excited state. A part of the excitation (absorbed) energy is lost on vibration relaxation, i.e.,...