SPANA for Spectral Data Analyses [About] Copyright (c) 2010 ykuroda All right reserved.

1. Introduction

  SPANA is a Windows program for analyses of spectral data in the UV/Vis region, which is developed on Microsoft Visual Basic. The program is installed by standard Windows procedures.^* The system equipped with over 500MB memories is preferable for smooth operation.

SPANA reads spectral data with a maximum of 10001 data points at a constant resolution into a maximum of 500 data channels (Ch.0 - Ch.499) and analyzes these spectra. Data files compatible with the spectrometers listed below can be read in their original form, but spectral data in other formats can also be read as long as the data is written in ASCII code. If the data is written in ASCII code, it can be read by specifying the data structure when reading it as "*.*" type data, or by rewriting it as a "TAB" or "DAT" format text file as shown below.^**, ***

* SPANA also runs on LINUX (ubuntu + Wine) under the environment equipped with WINDOWS fonts (Arial, MS Sans Serif, MS Serif, WINDNG3, and Symbol), which are attached to the program.
** The function to load data from arbitrary text file written by ASCII codes is added in Ver. 5.3.33
　　The function to load variable resolution data is added in Ver. 5.3.73.
*** If the data is arranged in "*.tab" format, "*.csv" files of Excel can also be read from SPANA by changing the extension to "tab".

２．Spectral Files recognized by SPANA

SPANA recognizes the data format with the file extension. The following file types can be recognized by SPANA of the present version

3. The area and the resolution of the spectral data and SPANA

In the default state of SPANA, the data points, the shortest wave length (Base Coordinate) and the resolution of target spectra are max 10001, 180nm and 0.5nm, respectively. Therefore, the range of target spectra must be between 180nm - 5180nm (=180 + 0.5 x 10000). The data having the different resolutions are converted into those of 0.5nm resolution by the function of the cubic spline interpolation.

In order to manage spectra in a different range from the default one, the base coordinate and the resolution must be adjusted by using the Ｆｉｌｅ−Ｓｅｔｔｉｎｇｓ−Ｓｐｅｃｔｒｕｍ Ｓｅｔｔｉｎｇｓ menu.

　　　　　　　　　　

As the results of the adjustments, the spectral range of SPANA becomes as follows.
　　[Base Coordinate] - [Base Coordinate + Resolution x 10000]
In this mode, the file format readable by SPANA is limited to "*.DAT" and "*.*" which are applicable for the spectra of arbitrary resolutions. The resolution of the each spectrum must be written in the spectral files for the former and assigned during the file reading procedure for the latter. ^*
If, when the base coordinate and/or resolution are changed, there are spectra which have been already read into SPANA, the spectra are converted into those of the newly assigned base coordinate and resolution by the function of the cubic spline interpolation. In the case that the resolutions of SPANA and the new reading spectrum are different, the spectrum is also converted into that of the resolution of SPANA. Thus, SPANA can handle, display and analyze spectra having different resolutions consistently.^**

* Since, if there is no consistency between the ranges of SPANA and the spectrum, SPANA generates program errors, the user needs to understand these relationships to change the base coordinate and resolution.
** The spline interpolation of the spectrum is based on the method of applying the cubic function to the spectrum where the errors between the data and theoretical values are usually considered to be small enough, though too large difference between resolutions of SPANA and the data can possibly result in a significant spectral distortion.


4. Numerical Operation in SPANA

SPANA performs following arithmetic operations for the spectral data.

     a) Addition, subtraction, multiplication, and division of a constant value
     b) Addition, subtraction, multiplication, and division between two spectra
     c) Reverse, exponential and logarithmic transformation
     d) Normalization
     e) Differentiation and integration
     f) Smoothing, Baseline estimation (BEADS)
     g) Wave length shift
     h) Estimation of the spectral area and overlapped area between two spectra
       etc.

5. Display of Spectra

SPANA provides the following functions for display of spectra

     a) Setting of display area (strength and wave length axes)
       (While SPANA usually sets the absorbance unit as the vertical axis and the wave
       length unit as the horizontal axis, these units are arbitrarily changeable.)
     b) Setting of the scales and grid for the vertical and horizontal axes
     c) Color setting for displayed spectra
     d) Change of the horizontal axis from the wave length mode to the wave number mode
     e) Print out and output the bitmap files of the displayed spectra
　　　　(in ver.5, including the print-out function for virtual printers such as the PDF one)
　　 f) 3D-display of the multiple spectral data set

6. Graph Making Function of SPANA

SPANA displays the appropriate graph plotting the observed data and theoretical curves for results of analyses of the titration data or rate data.
SPANA also displays the concentration variations of chemical species contained in the equilibrium or reaction systems and estimates the spectra of the intermediates.