TRANSFORM command

Data analysis makes direct use of tables. A new column can be created as a transformation of existing data. No additional steps are needed to create the column a single command defines the transformation and transfers the data (Figure 1). The results can be seen on the screen immediately, again without additional commands or setup steps. 

Figure 1. A single command allows Che user Co creaCe a new column in an RS/1 Cable as a transformation of existing data. (Reproduced with permission from University of South Carolina Press Columbia, S.C., 1986 Channing Russell In Research Data Management in the Ecological Sciences Michener, William, Ed. pp 373-381.)...

Separating the data transformation into three distinct steps enforces a completely modular software design. In practice, the data transformation is executed via command shell scripts, using freely available software for both the XSLT transformation and XSD validation. The raw data contained in the 39 surveys in the New Brunswick compilation are exported into 7,000 individual KML files, which can be viewed online at http //gdr.nrcan.gc.ca/geochem. 

Strength The Incident Command System and key positions were implemented early in response. Routine briefings were conducted for participating agencies. When Sheriff left the CP, command was transformed to other ACSO staff. 

Biocatalysis is still an emerging field hence, some transformations are more established than others.Panke et alP have performed a survey of patent applications in the area of biocatalysis granted between the years 2000 and 2004. They found that although hydrolases, which perform hydrolyses and esterifications, still command widespread attention and remain the most utilized class of enzyme (Figure 1.5), significant focus has turned towards the use of biocatalysts with different activities and in particular alcohol dehydrogenases (ADHs) - also known as ketoreductases (KREDs) - used for asymmetric ketone reduction. 

The effects of the circuit in the frequency domain were also characterized. The Fourier transform of the quasi-square waveform in Figure 8.41 was taken and the results shown in Fig. 8.44. Note that the third, fifth, seventh, and ninth harmonics are suppressed by about 40db, while the eleventh and thirteenth harmonics are about 20 dB less. The IsSpice simulation of this circuit was generated using the ICL feature of IsSpice. The format of the FOURIER command is shown below in Table 8.2. The resulting circuit characteristics in the frequency domain (Fig. 8.44) compare favorably to the resulting output from the IsSpice file (Table... 

With 2D experiments the situation is a little more complicated as the size of the overall digitised matrix depends on the number of time increments in tl as well as parameters specific to the 2D acquisition mode. Nevertheless, a digitised matrix of TD(2) X TD(1) complex data points is acquired and stored. Similar to ID the effective number o measured data points used for calculation TD(used) and the total number of data points SI to be transformed in t2 and tl may be defined prior to Fourier transformation. These parameters may be inspected and defined in the General parameter setup dialog box accessible via the Process pull-down menu. With 2D WIN-NMR the definitions for TD(2) and TD(1) are the same as for TD with ID WIN-NMR. However, unlike ID WIN-NMR, with 2D WIN-NMR SI(2) and SI(1) define the number of pairs of complex data points, instead of the sum of the number of real and imaginary data points. Therefore the 2D FT command (see below) transforms the acquired data of the current data set into a spectrum consisting of SI data points in both the real and the imaginary part. 

Fourier transformation in ID WIN-NMR is accomplished by choosing either the FT command in the Process pull-down menu (Fig. 5.3) or by simply clicking the FT button in the button panel. 

Both Fourier transform commands perform a Fast Fourier Transform (FFT) on the FID. If a baseline correction has not yet been performed on the raw data, a message box will appear which provides the option for performing a baseline correction (see section 5.3.3) on the time domain data (FID) prior to Fourier transformation. 

With 2D WIN-NMR, 2D Fourier transformation may be accomplished with the commands xfb, xtrf, xf2 and xfl accessible via the Process pull-down menu (Fig. 5.5). 

Hint If problems arise the xfb command, perform a stepwise Fourier transformation using the commands xf2 and xfl. 

This operation performs a transformation in the Fl direction in a similar way to that described for xf2. The type of the Fourier transformation depends on the value of the MC2 parameter, which must be correctly set as described above for the xfb command. 

The command xtrf automatically performs a user defined Fourier transformation in both the F2 and Fl dimension. Unlike the xfb, the xf2 and xfl commands, xtrf takes the processing parameter FT mod into consideration. This option is used for special case.s and may be adjusted to your personal needs, e.g. for a real instead of complex FT. 

The corresponding menu for 2D data to set up the window functions and their parameters in F2 (rows) and Fl (columns) is shown in Figs. 5.18 and 5.19. Processing parameters for both F2 and Fl may both be set prior to the consecutive Fourier transformation in both dimensions started with the xfb command. Alternatively the processing and Fourier transformation in t2 - initialized with the xf2 command - may be performed first. Suitable columns may then be used to adjust and set the processing parameters in tl prior to the second Fourier transformation, started with the xfl command. 

With 2D WIN-NMR baseline corrections are automatically applied for FIDs in t2 and tl prior to any processing when the Fourier transformation is initialized with the xfl, xfl, xfb or xtrf commands. According to the parameter BC mod set for F2 and Fl separately, either a simple DC correction or more sophisticated algorithms are applied to correct the FID baselines in F2 and Fl (Table 5.2), thereby taking into account the detection mode (single/quadrature). 

With 2D WIN-NMR zero filling is defined simply by setting SI for the F2 and Fl dimension in the Parameters dialog box opened with the General parameters setup command in the Process pull-down menu prior to Fourier transformation. 

After 2D Fourier transformation J-Resolved spectra usually contain a distortion along the horizontal line leading through the centre of the matrix. In order to get rid of this distortion and to separate chemical shifts from homonuclear J-couplings, the whole matrix is tilted. With 2D WIN-NMR a Tilt command is available which automatically adjusts the corresponding parameters (Tilt factor) and performs a tilt operation. 

After Fourier transformation, the effects on the spectrum of data manipulations, such as phase adjustments, can be controlled on a display before giving final calculating commands. Communication with the computer is generally via keyboard and graphic display. Light pen control via oscilloscope is also possible. 

Bruker uses the command EM (exponential multiplication) to implement the exponential window function, so a typical processing sequence on the Bruker is EM followed by FT or simply EE (EF = EM + FT). Varian uses the general command wft (weighted Fourier transform) and allows you to set any of a number of weighting functions (lb for exponential multiplication, sb for sine bell, gf for Gaussian function, etc.). Executing wft applies the window function to the FID and then transforms it. 

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