Methods to determine

There are several important partial results. (1) Definition of quality of the CT-data in relation to the imaging task, including a model of the X-ray paths and how it is used to predict the optimal performance. (2) A model and method to determine how the information of the imaged object transfer from the detector entrance screen through the detector chain to CT... 

This work presents two methods to determine the shape and severity of material discontinuities detected by means of the eddy current nondestructive control. 

The large temperature difference of the remarkable borehole, opposite other boreholes and their environment is significant. This high temperature difference is a typical feature for a small wall thickness between borehole and blade surface. For technical reasons, precise eroding of the boreholes is difficult. Due to this, the remaining wallthickness between the boreholes and the blade surface has to be determined, in order to prevent an early failure, Siemens/Kwu developed a new method to determine the wallthickness with Impulse-Video-Thermography [5],... 

A study of structural units, where a monomer is examined by physicochemical methods to determine its thermostability, its chemical and physical properties, and its sites of degradation. 

This experiment uses the molybdenum-blue method to determine the concentration of phosphate in a phosphate/sodium chloride mixture. Elow-injection analysis is used to increase the speed of analysis, allowing students to... 

Although intended for the biochemistry lab, this experiment provides analytical students with a practical characterization analysis. Of particular interest is the use of Job s method to determine the number of TNS (2-p-toludinylnaphthalene-6-sulfonate) binding sites on calmodulin, fluorescence is measured at 475 nm using an excitation wavelength of 330 nm. 

Suppose we have a sample containing an analyte in a matrix that is incompatible with our analytical method. To determine the analyte s concentration we first separate it from the matrix using, for example, a liquid-liquid extraction. If there are additional analytes, we may need to use additional extractions to isolate them from the analyte s matrix. For a complex mixture of analytes this quickly becomes a tedious process. 

The process of evaluating a method to determine those factors for which a small change in value has a significant effect on the method s results. 

The next step is to develop a method to determine the overall reUabiUty and failure probabiUty for systems constmcted of a variety of individual components. This requires an understanding of how components are linked. Components are linked either in series or in parallel. For series linkages, overall failure results from the failure of any of the components. For parallel linkages, all of the components must fad. An example of a series linkage is an automobde. The car is disabled if a flat occurs in any one of the four tires. This situation is linked in parallel to the spare tire. The car is completely disabled oidy if a flat occurs and the spare tire is flat. 

There are several methods to determine and compare the resistance to partial discharges. Some tests are done on finished cables, such as the U-bend test, and others are done on laboratory samples molded from the insulation, that are subjected to partial discharges created by sharp objects, such as needles under high voltages. The tests compare either the energy required or the length of time required to erode or fail (short circuit) samples of similar thickness. 

A rapid method to determine the calcium content of lead alloys is a Hquid-metal titration using lead—antimony (1%) (9). The end point is indicated by a gray oxide film pattern on the surface of a sohdifted sample of the metal when observed at a 45° angle to a light source. The basis for the titration is the reaction between calcium and antimony. The percentage of calcium in the sample can be calculated from the amount of antimony used. If additional calcium is needed in the alloy, the melt is sweetened with a lead—calcium (1 wt %) master alloy. 

Sample preparation for the modified Fischer assay technique, a standard method to determine the Hquid yields from pyrolysis of oil shale, is necessary to achieve reproducible results. A 100-g sample of >230 fim (65 mesh) of oil shale is heated in a Fischer assay retort through a prescribed temperature range, eg, ca 25.5—500°C, for 50 min and then soaked for 20 min. The organic Hquid which is collected is the Fischer assay yield (7). The Fischer assay is not an absolute method, but a quaHtative assessment of the oil that may be produced from a given sample of oil shale (8). Retorting yields of greater than 100% of Fischer assay are possible. 

Molecular Weight. Measurement of intrinsic viscosity in water is the most commonly used method to determine the molecular weight of poly(ethylene oxide) resins. However, there are several problems associated with these measurements (86,87). The dissolved polymer is susceptible to oxidative and shear degradation, which is accelerated by filtration or dialysis. If the solution is purified by centrifiigation, precipitation of the highest molecular weight polymers can occur and the presence of residual catalyst by-products, which remain as dispersed, insoluble soHds, further compHcates purification. 

Chemical methods to determine the crystalline content in silica have been reviewed (6). These are based on the solubility of amorphous silica in a variety of solvents, acids or bases, with respect to relatively inert crystalline silica, and include differences in reactivity in high temperature fusions with strong bases. These methods ate qualitative, however, and fail to satisfy regulatory requirements to determine crystallinity at 0.1% concentration in bulk materials. 

DS or IV Content. The traditional method to determine the % N content of a particular CN reUes on the decomposition of CN with H2SO4 over mercury. 

ASTM has estabhshed standard test methods to determine acid acceptance, acidity, alkalinity, color, corrosivity to metals, nonvolatile matter content. 

A high performance Hquid chromotography (hplc) method to determine citric acid and other organic acids has been developed (46). The method is an isocratic system using sulfuric acid to elute organic acids onto a specific hplc column. The method is sensitive for citric acid down to ppm levels and is capable of quantifying citric acid in clear aqueous systems. 

It is important to note that simulated distillation does not always separate hydrocarbons in the order of their boiling point. For example, high-boihng multiple-ring-type compounds may be eluted earher than normal paraffins (used as the calibration standard) of the same boiling point. Gas chromatography is also used in the ASTM D 2427 test method to determine quantitatively ethane through pentane hydrocarbons. 

The elemental composition of the fish otoliths is a potential source of the useful information to recreate environment history of the individual fish in some of the species. In-depth study of the chemical composition of the otolith center (formed eaidy in fish life) and otolith edge (formed later in fish life) ensures chronological and environmental information stored in the otoliths [1]. This infoiTnation may be achieved by X-ray electron probe microanalysis (EPMA). EPMA is the analytical method to determine the elemental composition of different otolith s parts, their sizes varying from ten up to some tens of microns. 

The no-load test is a very informative method to determine the no-load current, core and pulsation losses, friction and windage losses, magnetizing current and the no-load power factor. The test also reveals mechanical imbalance, if any, performance of the bearings, vibration and noise level of the motor. 

Step 8 Calculate step on the bypass valve. Now that the Ac bypass of the bypass valve is known, this must he translated into a new valve position. A similar process as described in Step 6 is used. However, in this case there is not an absolute value of c, but instead a Ac. Therefore, first determine the actual bypass bet- This is accomplished by taking the actual bypass valve position and using tlie manufacturer s curve (Figure 7-9). From this point, the method to determine the new valve position is the same as described in Step 6. 

Having previously introduced the key methods to determine the important variables with respect to stress and strength distributions, the most acceptable way to predict mechanical component reliability is by applying SSI theory (Dhillon, 1980). SSI analysis is one of the oldest methods to assess structural reliability, and is the most commonly used method because of its simplicity, ease and economy (Murty and Naikan, 1997 Sundararajan and Witt, 1995). It is a practical engineering tool used for quantitatively predicting the reliability of mechanical components subjected to mechanical loading (Sadlon, 1993) and has been described as a simulative model of failure (Dasgupta and Pecht, 1991). 

Although not widely used, there are other methods to determine the softening point, such as the capillary method, the flow point, the drop point, and the Kofier method. The different methods provide different values of the softening point. In general, the Ring and Ball method provides the highest softening point while the... 

The colour can be determined by various methods such as the Gardner, Barrett, iodine colour number or US Colophonium standard methods. Usually, the Gardner or the Barrett standards are used. A comparison between the different methods to determine the colour of resins is given in Table 9. In both methods, the colour is evaluated in resin solutions. A 50 wt% resin solution in toluene is used as the Gardner standard, and a solution of 2 g resin in 25 ml toluene is used in the Barrett... 

Case, R.C., a Method to Determine Exchanger Relief Valve Requirements, Proceedings, American Petroleum Institute, Division of Refining, Vol. 50, New York, 1970, p. 1082. 

Equation 5-197 is a polynomial of the third degree, and by employing either a numerieal method or a spreadsheet paekage sueh as Mierosoft Exeel, the roots (C ) of the equation ean be determined. A developed eomputer program PROGS 1 using the Newton-Raphson method to determine was used. The Newton-Raphson method for the roots of Equation 5-197 is... 

A eomputer program PROG52 was developed using the Newton-Raphson s method to determine the outlet eoneentrations of speeies A and B from the four stirred tank reaetors. The eight Equations 5-231 are supplied as funetions in the subroutine of PROG52 as ... 

Equations 6-94 and 6-97 are first order differential equations, and it is possible to solve for both the eonversion and temperature of hydrogenation of nitrobenzene relative to the reaetor length of 25 em. A eomputer program PLUG61 has been developed employing the Runge-Kutta fourth order method to determine the temperature and eonversion using a eatalyst bed step size of 0.5 em. Table 6-6 shows... 

At this point, following the chapters, the objectives have been defined, the effect of government regulations and standards are known, accidents have been identified and analyzed by various methods to determine the probability of an accident, and the accident consequences have been calculated. These parts must be assembled to present the risk and the analysis of the risk according to its various contributors. 

The only method to determine the actual system performance is to carry out measurements. The questions to be answered are What should be measured How and when How should the results be interpreted Some of the answers to these questions are found in the following sections. 

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