Data Processing Issues

The determination of polymer molecular mass and distribution by MALDI-MS requires not only accurate mass measurement but also quantitative measurement of ions. The equations used for molecular mass determination and polydispersity (PD) calculation are  

Surfynol 465 using sodium cationization. (b) AP MALDi ion trap MS/MS spectrum of the m/z 909 ion. (c) The chemical structure of 

Sion of Elsevier from Ref [143] American Society for Mass Spectrometry, 2006. 

In calculating the average molecular mass, the contribution of the cation attached to the polymer should be corrected. In addition, baseUne correction to a MALDI spectrum, if required, should be made with caution, as it can affect the polymer distribution [149]. 

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Memory depth (i.e., how many historical records are available) of transactional data is also important. For additional information on data processing issues, data types, and their sources readers are referred to Shapiro (2006). 

Earlier reference was made to published articles that described the use of optimization techniques for coating processes. In particular, the one presented by Porter et al. (7) provides a useful example of how aesthetic, functional, and processing issues can be dealt with. The key elements of the study that formed the basis for this article are listed in Table 3, while typical results obtained in this study are summarized in Table 4. From these data, it is possible to optimize the coating process with respect to ... 

Inefficient operations cost businesses untold amounts in financial and human capital. A poorly designed system coupled with inefficient processes may result in rework of development and commercialization activities, data integrity issues, inefficient use of resources, and delay in approval. Poorly designed processes may also... 

An important issue is the need to acquire both MS and MS-MS data for the unknowns. In general, this requires two injections with data-processing in between. The first run is done in full-spectrum LC-MS mode. Precmsor /w/z-values for relevant peaks in this chromatogram have to be determined in (manual) data processing. The /w/z-values found are then used in a time-scheduled product-ion MS-MS procedure using multiple precmsor-ions. Alternatively, data-dependent acquisition (DDA, Ch. 2.4.2) can be used, as demonstrated by Drexler et al. [106]. An alternative to DDA in a triple-quadrupole instrument is the RF product-ion analysis mode (RFD), proposed by Kienhuis and Geerdink [107]. 

Our experience with applications of the powder method in diffraction analysis was for the most part, conceptual, and in the remainder of this book, we will discuss key issues that arise during the processing and interpretation of powder diffraction data. Despite the apparent simplicity of onedimensional diffraction patterns, which are observed as series of constructive interference peaks (both resolved and partially or completely overlapped), created by elastically scattered waves and placed on top of a nonlinear background noise, the complexity of their interpretation originates from the complexity of events involved in converting the underlying structure into the experimentally observed data. Thus, nearly every component of data processing in powder diffraction is computationally intense. 

Figure 4.1. The flowchart illustrating common steps employed in a structural characterization of materials by using the powder diffraction method. It always begins with the sample preparation as a starting point, followed by a properly executed experiment both are considered in Chapter 3. Preliminary data processing and profile fitting are discussed in this chapter in addition to common issues related to phase identification and analysis. Unit cell determination, crystal structure solution and refinement are the subjects of Chapters 5,6, and 7, respectively. The flowchart shows the most typical applications for the three types of experiments, although any or all of the data processing steps may be applied to fast, overnight and weekend experiments when justified by their quality and characterization goals.

Within 10 years of the first attempts to use NIR multispectral or hyperspectral imaging for food products, prodigious advances have been achieved such that NIR hyperspectral imaging is now commonly used in both laboratory and on-line applications. Yet, this outstanding technique continues to raise many questions that must be addressed before it is more widely accepted. Such questions relate not only to the hardware and data processing but also to specific issues related to NIR imaging. 

The Environment Information Centre (EIC) has two main tasks. It collects, processes, issues and stores environmental data. EIC transfers data and information to several Baltic, Nordic and European partners. It acts as the counterpart to the European Environmental Agency (EEA)... 

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