Scan converter

Evaluation of tracer on the skin surface was conducted with the VITAE system, following a protocol similar to that described elsewhere 3) The system quantifies fluorescence intensity in the following manner a television camera scans the surface area of a body part 30 times per second. A video digitizer in the computer takes one of these scans, converts the analog camera output to digital values on the basis of a 16 level grey scale, and displays the image on a TV monitor. The data is then stored on disk and is available for later analysis. 

Figure 16.34 (a) A schematic DSC scan, showing how T, AH, and ACp are obtained, (b) A temperature scan, converted to partial molar heat capacity for 1 mg/mL hen egg white lysozyme (shown in the upper right corner) in 0.2 M glycine buffer, pH 2.7. Data obtained at a scan rate of 1°C/min in a Nano DSC. (Courtesy of TA Instruments, New Castle, DE, www.tainstruments.com.)... 

Material Veloeity. Defines the velocity, in metres/sec, of ultrasound in the material of the test piece used to convert A-scan signal time to distances within the test piece. 

Fig. 2 shows the CFRP-sandwich specimen and the transducer mounted on the scanner. Fig. 23 presents a C-scan of the specimen as first interesting result. Only the defects visible from the outside are indicated. The distance between transducer and specimen was smaller than the focal length, so that the angle of incidence at the edge of the sound beam converts the longitudinal waves to Rayleigh-waves in the specimen. These waves provide a very sharp image of the surface. This method opens the possibility for a non-contact acoustic microscope. 

The sample frequency of the ADC (analogue to digital converter) should be 8 times higher than the test frequency (centre frequency of the spectrum). In dependence of the application, different ADC- boards are used. A standard board (20520) provides 8 bit resolution and up to 100 Msamples/s in single shot mode. For manual tests, up to 400 Msamples/s can be reached in the repetition mode. For scanning systems with high frequencies boards up to 400 Msamples/s (single shot) are available. 

Fig. 10. Differential scanning calorimetry of cellulose triacetate. Second heating at 20°C/min. glass-transition (T temperature = 177 " C crystallization on heating (T)/j) = 217 C melting temperature (Ta) = 289 C. To convert to cal, divide by 4.184.

Rapid-Scan Corrosion Behavior Diagram (CBD) Basically, all the same equipment used in the conductance of an ASTM G5 slow-scan polarization study is used for rapid-scan CBDs (that is, a standard test cell, potentiostat, voltmeters, log converters, X-Y recorders, and electronic potential scanning devices). The differences... 

A number of other thermodynamic properties of adamantane and diamantane in different phases are reported by Kabo et al. [5]. They include (1) standard molar thermodynamic functions for adamantane in the ideal gas state as calculated by statistical thermodynamics methods and (2) temperature dependence of the heat capacities of adamantane in the condensed state between 340 and 600 K as measured by a scanning calorimeter and reported here in Fig. 8. According to this figure, liquid adamantane converts to a solid plastic with simple cubic crystal structure upon freezing. After further cooling it moves into another solid state, an fee crystalline phase. 

Figure 7.7. A finite element model of a bone specimen in compression. This model was created by converting the voxels from a microcomputed tomography scan into individual bone elements. Loads can then be applied to the model to understand the stresses that are created in the bone tissue.

Since AH is proportional to the area of the DTA peak, one ought to be able to measure heats of reaction directly, using the equation 7.1.22. Indeed we can and such is the basis of a related method called Differential Scanning Caloiimetiy (DSC), but only if the apparatus is modified suitably. We find that it is difficult to measure the area of the peak obtained by DTA accurately. Although one could use an integrating recorder to convert the peak to an electrical signal, there is no way to use this signal in a control-loop feed-back to produce the desired result. 

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