Quality control analysis techniques

Guide to Data Analysis and Quality Control Using CUSUM Techniques. Uses and Value of CUSUM Charts in Business, Industry, Commerce and Public Service , BS 5703-1 2003, British Standards Institute (BSI), London, UK, 2003. 

Propagation of error, sequential analysis, and quality control are additional statistical techniques with which the chemical engineer in design should be acquainted. The intent of this section will only be to outline the value of these tools and leave the details to other references. 

For a number of decades. X-ray fluorescence analysis (XRF) has established itself as a multielement analytical technique, which is capable of yielding quantitative information on the elemental composition of a variety of materials in a nondestructive manner. In its wavelength-dispersive configuration, it has proved itself as very important for routine analysis and quality controL The energy-dispersive configuration, on the other hand, offers wide potential as a simple tool for various laboratory and field applications in multielement analysis (Van Grieken and Markowicz 2002). 

FTIR spectrometry is a widely used technique for materials analysis by quality control technicians, engineers, students, synthetic chemists, and other scientists. Every operator, whether a spectroscopist or not, can get quick, accurate, precise results by this technique. Today s QA/QC labs require instruments that are reliable and rugged, yet sensitive and easy to use. These features are distinctive to the FTIR instruments, which makes it the perfect system for QA/QC applications in the routine analysis of polymers and polymer components. 

When analyzing complex samples, like the ones in food industry, a separation method is needed to identify and quantify the components of the sample. Among all the commonly used separation methods, CE and microchip-CE display integration compatibility with ECD systems. In addition, microchip-CE offers short analysis time, high separation efficiency, low cost, and low consumption of sample and reagents, and miniaturization. These techniques are particularly well suited for portable instruments and field applications. The combinations of microfluidics, CE, and ECD methods have led to the development of successful portable systems with applications in environmental analysis, food quality control, and medical testing [55, 56,182-184]. 

Dagleish, M. and N. Hoose. 2008. Highway Traffic Monitoring and Data Quality. Boston Artech House. Describes vehicle, traffic, and environmental sensors and applications for capturing data, such as vehicle weight, size, speed, license number, and travel time. Provides statistical techniques for data analysis and quality control. 

Raman spectroscopy has been used to characterize organic fibers and films since the 1960s. Initially, Raman spectroscopy was used primarily to identify the material in the same way that infrared (IR) spectroscopy was used. Chemical identification and quantification are still used extensively to determine the type of polymer, the type and amount of comonomers, and the type and amount of pigments, dyes, or other additives. This has been used in forensic science, archaeology, competitive analysis, and quality control. The techniques are nearly identical to those used for the identification of other solids and liquids, with minor modifications required by the fibrous or filmlike nature of the materials. This application will be discussed in Section II,... 

Chromatographic techniques, particularly gas phase chromatography, are used throughout all areas of the petroleum industry research centers, quality control laboratories and refining units. The applications covered are very diverse and include gas composition, search and analysis of contaminants, monitoring production units, feed and product analysis. We will show but a few examples in this section to give the reader an idea of the potential, and limits, of chromatographic techniques. 

Nuclear Magnetic Resonance (nmr). The nmr analysis has been used in the polymer industry for some time to measure properties such as amount and type of branching, polymerized ethylene oxide content, and hydroxyl content. The same techniques are applicable to waxes, and are used for both characterization and quality control. 

Like XPS, the application of AES has been very widespread, particularly in the earlier years of its existence more recently, the technique has been applied increasingly to those problem areas that need the high spatial resolution that AES can provide and XPS, currently, cannot. Because data acquisition in AES is faster than in XPS, it is also employed widely in routine quality control by surface analysis of random samples from production lines of for example, integrated circuits. In the semiconductor industry, in particular, SIMS is a competing method. Note that AES and XPS on the one hand and SIMS/SNMS on the other, both in depth-profiling mode, are complementary, the former gaining signal from the sputter-modified surface and the latter from the flux of sputtered particles. 

Heydorn K (1991) Quality Control in activation analysis. J Radioanal NucI Chem 151 139-148. Heydorn K (1995) Validation of neutron activation techniques. In Quevauviller Ph, Maier EA. 

Particularly for direct microanalytical techniques using <10 mg of sample for analysis, it is highly desirable to obtain quantitative information on element- and compound-specific homogeneity in the certificates for validation and quality control of measurements. As the mean concentration in a CRM is clearly material-related, the standard deviation of this mean value should represent the element s distribution in this matrix rather than differences in the analytical procedures used. 

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