Sequential recording

In a spectrophotometer, the fixed detector records the wavelength selected by a rotating grating located in the monochromator. This system allows sequential recording of line intensities. 

The sequential recording of electron spectra for small changes in the photon energy finally leads to the desired complete data set for electron intensities I = I(hv, kin). The data can be mapped in three dimensions, or in two dimensions if a grey scale is used for the intensities (black and white for extreme values of... 

In particular, if the number of photons detected during each period is recorded as a sequential record (instead of the simpler data recording mode utilized for this work) then autocorrelation functions and spectral densities of concentration... 

This occurs mainly in distal occlusions of a nondominant LCX or RCA and in the enzymatic infarction (necrosette). Sometimes an apparently normal or mildly abnormal ECG (positive and symmetrical T wavein Vl-V2)may be seen in patients at high risk. To take sequential recordings is mandatory to check the presence of ST-segment deviations. 

The diffusion of TMR/POPE molecules in the membrane was investigated by sequentially recording images from the sample. Figure 14 shows such a sequence taken at 10-ms intervals from a 12.2 x 9.5-fim2 area of a POPC membrane doped with TRM/POP at 10 8mol-mol 1. The migra-... 

Sequential recording Controlled by an internal clock oscillator, the sequencer counts through a range of subsequent address words. The result is a sequence of waveform measurements. The individual measurements can be multidimensional themselves, due to the capabilities of the channel control. The sequence can be recorded at almost any rate. It can be triggered by an experi-ment trigger", and a specified number of triggered sequences can be accumulated. 

Sequential recording, also known as double kinetic mode [353] or time-lapse recording , adds one or two additional dimensions to the photon distributions recorded by multidetector operation and multiplexing. Controlled by its internal clock oscillator, the sequencer switches through a specified number of memory blocks. Each memory block contains the photon distributions of all detectors and multiplexing channels. Sequential recording in a multidetector system is illustrated in Fig. 3.7. For sake of simplicity, multiplexing has been omitted. 

Fig. 3.7 Sequential recording. Triggered by the experiment trigger, the sequencer switches through a large number of memory blocks. Each block contains the photon distrihution over the time in the signal period, t, over the detector channels, and (not shown) over possible multiplexing channels...

Because the sequence is controlled by the TCSPC hardware, it is possible to achieve extremely fast and accurate stepping, down to less than a microsecond per data block. Of course, sequential recording can also be achieved by software control of a TCSPC device, and advanced TCSPC devices in fact include operating modes for recording software-controlled sequences. However, modem computers are far from being real-time systems. Stepping faster than 100 ms per step becomes inaccurate, which makes an accumulation of software-controlled sequences impossible. 

Fig. 3.9 Unlimited sequential recording by memory bank swapping. When one memory bank is full, the sequencer swaps the banks. While the sequencer writes into one bank, the other one is read by the computer...

This difficulty is easily avoided by fluorescence lifetime detection. By using the sequential recording capability of multidimensional TCSPC, the fluorescence transients can be directly observed. A simple setup for recording the nonphotochemical quenching is shown in Fig. 5.31. 

Fig. 5.38 Stopped-flow measurement by TCSPC, triggered sequential recording, 100 ms per curve. Left Recorded sequence after a single stop. Right 500 stops accumulated. Data courtesy of Osman Bilsel, University of Massachusetts Medical School, Worcester, MA...

A particularly interesting piece of evidence for single-molecule behavior is the report of sudden spectral changes observed in sequentially recorded spiectra in the same paper [15]. 

The roots of CD-R are found in audio CD, and thus some of the parameters, recording formats, and performance features are based on the Red Book standard (which has tended to be a handicap). The CD format (Bouwhuis et al, 1985) is not well suited for random access block oriented recording. The CD format leads to a sequential recording system, much like a tape recorder. 

AlAs/GaAs. Sample preparation and laser melting techniques are found in reference [62], Images of Al, Ga, Si, and O were sequentially recorded with a resistive anode encoder as the sample was depth profiled with Cs" and positive secondary ions in a Cameca IMS 5f in the microscope mode of operation. Two-dimensional cross sections of the Al, Ga, Si, and O images from a 60 pm rectangular slice centered around the 4 pm laser stripe were then computer generated and are shown in Fig. 4.30a. Depth profiles of Al, Ga, and O from selected 4 pm areas were also generated in the non laser-striped area in Fig. 4.30b and in the laser-striped area in Fig. 4.30c. Samples similar to the one in Fig. 4.30 have been analyzed with TEM, SEM, and electron dispersive X-ray spectroscopy (EDS) in addition to SIMS for full characterization [62]. 

Morrow MM, Miller LE (2003). Prediction of muscle activity by popylations of sequentially recorded primary moto" cortex neurons. J Neurophys 89 2279-2288. 

The library consists of a binary file. It consists of a header defining the number and type of custom field as well as the column description for the retention indexes. The data for each compound are recorded in an indexed sequential record according to a proprietary format. Each record includes the parameter pertinent to the compounds ... 

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