Weight assessing

This was described in 1959 by Streicher , and consists of one period of exposure to a boiling solution of 50 mass% H2SO4 -I- 25 g 1 Fe2(S04)j for 120 h, assessment being based on mass loss (see Table 19.4). Streicher, however, usually reports a ratio of mass loss of sample to be assessed/weight loss of annealed sample (g dm ), and as for the HNO3-HF test considers that a ratio > 1-5-2-0 indicates susceptibility for Type 304 Streicher considers a rate >0-76 mm/y to indicate susceptibility, but Brown considers a higher figure to be acceptable (see Table 19.4)... 

If diuretic therapy is warranted, monitor for therapeutic response by assessing weight loss and improvement of fluid retention, as well as exercise tolerance and presence of fatigue. 

Close monitoring should follow to assess weight, BMI, waist circumference, and presence of complications related to the treatment plan. If weight-loss goals are not attained, determine reasons for failure. 

Usually, some lines of evidence will not be suitable for direct incorporation into quantitative analysis. Semiquantitative or qualitative methods will then be needed to weigh the different lines of evidence, including the quantitative assessment, and integrate them for decision making. Methods for assessing weight of evidence were outside the scope of the workshop that developed this book but are discussed by Suter et al. (2000) and were recently the focus of another workshop (Chapman et al. 2002). Whatever method is used for weighing different lines of evidence, it will be important to characterize uncertainties in each line of evidence and show their effect on the overall assessment outcome. 

The requirement for continuous production at speed implies that there must be convenient equipment for assessing weight and so ensuring uniformity. Almost always the instrument used for this work is the beta gauge, which records the attenuation of a beam of electrons from a weak radio-active source as it is passed through the coated web. The gauge can be calibrated with samples of known composition and weight, and the results are expressed in terms of mass per unit area . 

The assessment weighting for the laboratory component of the course is 10%, and this is split 2% for the pre-laboratory exercises and 8% for the laboratory report. Attendance and satisfactory completion of the laboratory work are course requirements. 

On the other hand, if the hazard is toxicity, process alternatives can be compared by assessing the mass of toxic material that would enter the vapor phase on release from containment, weighting the components according to their lethal concentration. 

We must be careful in assessing the experimental results on the viscosity of branched polymers. If we compare two polymers of identical molecular weight, one branched and the other unbranched, it is possible that the branched one would show lower viscosity. Two considerations enter the picture here. First, since the side chains contribute to the molecular weight, the backbone chain... 

In selecting a flame retardant for a given appHcation, the cost contribution of the flame retardant to the final polymer compound must be taken into account. Assessment of cost should be done on a cost per volume basis rather than a simple cost per weight basis. 

The characteristics of interior paints that require testing and analysis include hiding and appearance, package stabiHty, adhesion, spatter resistance, flow and leveling, color and sheen uniformity, touch-up, stain removal, burnish resistance, and block and print resistance. A popular test that assesses the wet abrasion resistance of an interior paint is to measure its scmb resistance. A mechanical device is used to scmb a paint film of a specified thickness with a standard bmsh and abrasive cleanser suspension. The number of scmb cycles (back and forth movements of the weighted bmsh) at various end points (first cut through, or 50% removal of the film) is then recorded. Scmb resistance usually holds steady or decreases slightly as PVC is increased, but drops quickly once the CPVC is exceeded in a paint formulation. 

Years of development have led to a standardized system for objective evaluation of fabric hand (129). This, the Kawabata evaluation system (KES), consists of four basic testing machines a tensile and shear tester, a bending tester, a compression tester, and a surface tester for measuring friction and surface roughness. To complete the evaluation, fabric weight and thickness are determined. The measurements result in 16 different hand parameters or characteristic values, which have been correlated to appraisals of fabric hand by panels of experts (121). Translation formulas have also been developed based on required levels of each hand property for specific end uses (129). The properties include stiffness, smoothness, and fullness levels as well as the total hand value. In more recent years, abundant research has been documented concerning hand assessment (130—133). 

A convenient method for assessing the extent of surface oxidation is the measurement of volatile content. This standard method measures the weight loss of the evolved gases on heating up to 950°C in an inert atmosphere. The composition of these gases consists of three principal components hydrogen, carbon monoxide, and carbon dioxide. The volatile content of normal furnace blacks is under 1.5%, and the volatile content of oxidized special grades is 2.0 to 9.5%. 

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