Sampling, data simultaneous

Position Sensitive Detectors. By replacing the scintillation detector in a conventional powder diffractometer with a Position Sensitive Detector (PSD), it is possible to speed data collection. For each x-ray photon received a PSD records the angle at which it was detected. Typically, a conventional scintillation detector records x-ray photons in a range of a few hundredths of a degree at a time. A PSD can measure many degrees (in 20) of a powder pattern simultaneously. Thus, for small samples, data collection, which could require hours with a conventional detector, could take minutes or even seconds with a PSD. 

As part of a study to test the use of population panels as a method for assessing odour annoyance in a direct way, a comparison of the odour annoyance experienced by such population panels and the odour immission concentrations expressed in odour units/m3 of air samples taken simultaneously, was made. It was found that in a city where odour annoyance occurs regularly, no relationship could be found between the amount of odour annoyance experienced and the immission concentrations. Furthermore, it was shown that the odour concentrations of pleasant smells (meadows forest) in an unpolluted area may be as high as 24 odour units. It is concluded that the amount of annoyance caused by odours can not be deduced from concentration measurements, but should be assessed in a direct way. Population panels provide a good means of obtaining such data. They are reliable and can give indications about the important sources of annoying odours in complex industrial areas. 

As an alternative, a representative value for A He/x in Equation (48) can be obtained from all data simultaneously by using a regression of A He versus x (e.g., Aeschbach-Hertig 1994 Hohmaim et al. 1998). This technique implicitly assumes that the ratio A" He/x is the same for all samples. Figure 15 demonstrates that in many lakes a linear correlation between A He and x is a reasonable approximation. 

For this catalyst sample, additional adsorption experiments are available. After the first adsorption experiment, reaction studies were performed with the catalyst sample. Then the catalyst was regenerated with heat treatment, and a second adsorption experiment was performed, followed by an additional reaction study, and so on. The additional adsorption data are shown in Figure 9.16. Notice these are not replicate experiments, because the adsorption experiments are performed after different reaction studies have been performed, and the catalyst regeneration step does not necessarily return the catalyst to exactly the same condition. Estimating the parameters by fitting all of these data simultaneously produces the solid line in Figure.9,16 and... 

With low-resolution instruments, it is seldom pos- siblc to locate peaks that are unique to each component of a mixture. In this situation, it is still possible to complete an analysis by collecting intensity data at a number of mfz values that equal or exceed the number of sample components. Simultaneous equations are then developed that relate the intensity of each nnz value lo the contribution made by each component lo... 

However, almost all advanced TCPCS devices are able to reeord lifetime data and PCS data simultaneously [25, 65]. The advantage compared to the traditional approach is that PCS and lifetime data originate from the same sample, from the same spot of a sample, or even from the same molecules. TCSPC data can therefore be used to distinguish between different types of molecules, different quenching states, or different binding or conformation states of dye-protein eomplexes it is also possible to include lifetime variations in the correlation [498, 548]. The principle of TCSPC-based PCS is shown in Pig. 5.109. 

Fig. 7. Field-effect data for three a-Si H samples deposited simultaneously on different types of quartz Commercial optical (CO), Suprasil 2 (SI), and Suprasil W (OH free). These substrates had been cleaned, etched, and annealed prior to deposition. Plotted is the conductance G versus the interface surface charge density. [From Goodman (1982).]...

Sample outputs for epoxy + AEP are shown in Figures 2 and 3. Figure 2 illustrates the typical fit that is possible using data from a single experiment. Kinetic constants obtained from one trial do not satisfactorily predict other experiments at different starting temperatures, however. Therefore, it is advantageous to correlate several files of data simultaneously, as in Figure 3. The equation obtained when this is done represents the adiabatic reaction kinetics ... 

In the RT-FTIR technique, the sample is simultaneously expwsed to the polymerizing UV-irradiation beam and to the analyzing IR beam (Fig. 1), which monitors the resulting drop of absorbance. In all the reported data the UV light was a medium pressure mercury lamp, with a broad UV spectra emission. 

Bateman et al. (2009) describe the use of a nonhybrid Orbitrap mass spectrometer for both qualitative and quantitative analysis of in vitro and in vivo samples. Data collection used nonselective MS/MS data capture with the HCD-cell-enabled system. Metabolic stability was determined for a series of compounds with simultaneous determination of metabolites and their structures from the MS and MS/MS data sets. Plasma drug levels were measured using full-scan HRMS data collected using a FWHM resolution of 25,000. It was found that this was the minimum resolution required for acceptable quantification at low levels in plasma. Circulating metabolites were also detected and time profiles plotted to show relative abundance of several metabolites. 

A second category of instrument is the simultaneous WD-XRF analyzer. This instrument is designed with a specified number (usually in the range 8-20) of individual fixed spectrometer channels , each optimized for the determination of a designated element. Multielement analysis is vmdertaken very rapidly by acquiring data simultaneously from all channels. Such instruments offer, therefore, high analytical productivity of benefit in production and quality control laboratories that are required to analyze the same sample-type on a routine basis. 

The maximum levels for T-2 and HT-2 are still under consideration. An indicative level for the sum of T2 and HT-2 was set in 2013 (Commission Recommendation 2013/165/ EU, European Commission, 2013). It is 200 gg/kg for barley (including malting barley) and 50 gg/kg for processed cereals. According to this recommendation, member states should also collect more data on the occurrence of T-2 and HT-2 in cereal and cereal products. Furthermore, more information is needed on year-to-year variation, the effects of food processing and agronomic factors on the presence of these toxins. It is also encouraged that samples be simultaneously analysed for the presence of T-2 and HT-2 and other Fusarium toxins, since they often co-occur in the samples. 

Sequential collection of spectral data by locally scanning the selected areas within a static sample or simultaneous acquisitions of thousands of spectra resolved spatially PAT application... 

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