Slip quality testing

Over the twentieth century, the mbber industry has developed special rheometers, essentially factory floor instmments either for checking process regularity or for quality control purposes, for instance, the well-known Mooney rheometer (1931), the oscillating disk rheometer (1962), and the rotorless rheometer (1976). All those instmments basically perform simple drag flow measurements but they share a common feature During the test, the sample is maintained in a closed cavity, under pressure, a practice intuitively considered essential for avoiding any wall slip effects. Indeed it has... 

The DIN method is given in ISO 464954. The principle of the machine is illustrated in Figure 11.5 a disc test piece in a suitable holder is traversed across a rotating drum covered with a sheet of the abradant, which is why it is also called the rotary drum abrader. In this way, there is a relatively large area of abradant, each part of which is passed over in turn by the test piece, so that wear of the abradant is uniform and relatively slow. In the standard method there is no provision for changing conditions from those specified, other than a lower force for soft rubbers, but it would be possible to use other abradant cloths or papers and to vary the force on the test piece. The degree of slip is 100% and it would be inconvenient to test in the presence of a lubricant. Although not versatile, the method is very convenient and rapid and well suited to quality control. 

Again regardless of in-house or outsource development, document a list of features and prioritize them. Break the project down into short, timeboxed iterations, each focusing on one or two of these features (Chapter 5). Do not let the iteration deadline slip. Reduce the scope of the iteration if necessary. Implement features with high business values and high business and technical risks in early iterations. Make sure each iteration delivers a production quality partial system to solicit feedback and let the system grow incrementally. The project plan should be adjusted based on the feedback. It is OK if the initial project plan is not accurate. However, it should become more and more accurate as more iterations are completed. Test and integrate early and frequently. 

Those for crude oils include the free fatty acids (FFA), iodine value (IV), saponification value (SV), refractive index (RI), specific gravity (SG), unsapo-nifiable matter (US), and moisture plus impurities (M I). These are intended to give a quick impression of the authenticity of the oil and the likely losses in refining. For refined oils, the values also usually include the colour, peroxide value (PV), slip melting point (SMP) and solid fat content (SFC), if appropriate. These are indications of quality and behaviour in use. As the SFC test relies on nuclear magnetic resonance, these values are also known as NMR or N values. The Malaysian standard for crude and refined CNO (MS 1987) is shown in Table 6.7 and the Codex (2001) draft standard in Table 6.8. 

Batch Analyzers. The American Monitor Programachem 1040 does one test at a time on up to 89 samples at up to 15 results per minute. A prepunched program card automatically sets virtually all of the system variables for each method on insertion into the instrument card-reader. A second-generation instrument, the KDA, was shown in 1975. This provides an integrated system from request slip to report form, with a design heavily dependent on the dedicated minicomputer. Another feature offered is graphics, which allows an oscilloscopic display of calibration curves, kinetic reaction-curves, quality-control points, etc. 

Validation of Generated Reactions. A major problem for the generator has always been that of recogruzing and deleting unacceptable, non-viable reactions. The chemistry of viable reactions is of course more complex and variable than addressed by the simple, abstracted Azx-lists. In the past, reactions which were clearly not viable were deleted by a set of broad mechanistic tests, but many still slipped past this net and their presence tended to lower the credibility of the program in the eyes of its users. On the other hand, however, if the mechanistic tests are too restrictive, they will probably delete some viable routes. Hence another way to assess the quality of generated reactions was needed. 

Small-scale spills of hazardous chemicals can occur in laboratories in educational institutions, quality control and testing laboratories, hospitals, greenhouses, and wherever small quantities of hazardous chemicals are handled. Such spills have less potential to cause widespread problems than spills on an industrial scale. However, they pose a risk to the health of workers in the laboratory or at the site of the spill from the inhalation of fumes, from the potential hazards of reactive chemicals, and, in the case of liquids, from slipping on wet floors. It is recognized that small spills should be cleaned up as quickly, responsibly, and efficiently as possible. Workplaces must have a protocol for handling spills and provide spill kits in appropriate locations. It is important that such kits be readily available in locations where they are easily accessed when needed. Furthermore, a plan needs to be in place to guide what is to be done with the residues from cleanup of the spills (National Research Council, 1995). 

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