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Data, using effectively

When experiments are carried out to select a suitable dryer and to obtain design data, the effect of changes in various extern variables is studied. These experiments should be conducted in an experimental unit that simulates the large-scale diyer from both the thermal and the material-handling aspects, and only material which is truly representative of full-scale production should be used. [Pg.1182]

In practice the clamping pressure will also depend on the geometry of the cavity. In particular the flow ratio (flow length/channel lateral dimension) is important. Fig. 4.42 illustrates typical variations in the Mean Effective Pressure in the cavity for different thicknesses and flow ratios. The data used here is typical for easy flow materials such as polyethylene, polypropylene and polystyrene. To calculate the clamp force, simply multiply the appropriate Mean Effective Pressure by the projected area of the moulding. In practice it is... [Pg.294]

The supplementary requirements provide a welcome addition to this somewhat inadequately specified clause of ISO 9001. However the reference to clause 4.1.1.2 with respect to objectives specified in the quality policy is somewhat ambiguous. Clause 4.1.1.2 does not require objectives to be included in the policy this is required in clause 4.1.1.1. As stated previously, system effectiveness is judged by how well the system enables implementation of policy and achievement of objectives. Therefore, requiring records that contain evidence of this is a logical interpretation. Such records need to identify the matters reviewed, the results, the actions, and the decisions taken, together with the names of those responsible and the date by which actions are to be completed. The records should also contain the data used to conduct the review as the basis upon which the decisions have been made and so that comparisons can be made at later... [Pg.139]

For catastrophic demand-related pump failures, the variability is explained by the following factors listed in their order of importance system application, pump driver, operating mode, reactor type, pump type, and unidentified plant-specific influences. Quantitative failure rate adjustments are provided for the effects of these factors. In the case of catastrophic time-dependent pump failures, the failure rate variability is explained by three factors reactor type, pump driver, and unidentified plant-specific Influences. Point and confidence interval failure rate estimates are provided for each selected pump by considering the influential factors. Both types of estimates represent an improvement over the estimates computed exclusively from the data on each pump. The coded IPRDS data used in the analysis is provided in an appendix. A similar treatment applies to the valve data. [Pg.104]

Solvents and pH may have a marked effect on stereochemistry as was illustrated in Chapter 1, and the generality given there is useful, A further example of the stereochemical influence that may be exerted by proper choice of catalyst and solvent is shown in the hydrogenation of a complex enamine, By proper choice of conditions high yields of either the cis or trans product could be obtained. Selected results are shown below (52) (data used with permission). [Pg.46]

The guidance obtainable from break-even charts is limited and should be used only with other criteria in formulating decisions. The effects of policy decisions may alter the data used and vitiate or amend the results disclosed. [Pg.1039]

Polymerization thermodynamics has been reviewed by Allen and Patrick,323 lvin,JM [vin and Busfield,325 Sawada326 and Busfield/27 In most radical polymerizations, the propagation steps are facile (kp typically > 102 M 1 s l -Section 4.5.2) and highly exothermic. Heats of polymerization (A//,) for addition polymerizations may be measured by analyzing the equilibrium between monomer and polymer or from calorimetric data using standard thermochemical techniques. Data for polymerization of some common monomers are collected in Table 4.10. Entropy of polymerization ( SP) data are more scarce. The scatter in experimental numbers for AHp obtained by different methods appears quite large and direct comparisons are often complicated by effects of the physical state of the monomei-and polymers (i.e whether for solid, liquid or solution, degree of crystallinity of the polymer). [Pg.213]

One final point should be made. The observation of significant solvent effects on kp in homopolymerization and on reactivity ratios in copolymerization (Section 8.3.1) calls into question the methods for reactivity ratio measurement which rely on evaluation of the polymer composition for various monomer feed ratios (Section 7.3.2). If solvent effects arc significant, it would seem to follow that reactivity ratios in bulk copolymerization should be a function of the feed composition.138 Moreover, since the reaction medium alters with conversion, the reactivity ratios may also vary with conversion. Thus the two most common sources of data used in reactivity ratio determination (i.e. low conversion composition measurements and composition conversion measurements) are potentially flawed. A corollary of this statement also provides one explanation for any failure of reactivity ratios to predict copolymer composition at high conversion. The effect of solvents on radical copolymerization remains an area in need of further research. [Pg.361]

Most of the data used for compiling such maps have been obtained for the flow of water and air at near atmospheric temperature and pressure, and scaling factors have been introduced to extend their applicability to other systems. However, beating in mind the diffuse nature of the boundaries between the regimes and the relatively minor effect of... [Pg.184]

The effect shown in Fig. 9 is a result of the bond-bond interaction which is a characteristic feature for chains and rings of two-valent chalcogen atoms. It can also be recognized from the relatively large bond interaction force constants fir of such compounds. The stretching force constants /r(SS) of polysulfur compounds depend on the SS bond distances as shown in Fig. 10. The data used in this figure include several excited electronic states of the S2 molecule as well as the disulfide anion and a number of sulfur homocycles [77]. [Pg.226]

Reference Dose (RfD)—An estimate (with uncertainty spanning perhaps an order of magnitude) of the daily exposure of the human population to a potential hazard that is likely to be without risk of deleterious effects during a lifetime. The RfD is operationally derived from the no-observed-adverse-efifect level (NOAEL-from animal and human studies) by a consistent application of uncertainty factors that reflect various types of data used to estimate RfDs and an additional modifying factor, which is based on a professional judgment of the entire database on the chemical. The RfDs are not applicable to nonthreshold effects such as cancer. [Pg.245]

The use of plastics as an energy source was demonstrated on a commercial scale at ICl Materials plastics manufacturing site in Dumfries, UK. This paper covers the preparation and use of pre- and post-consumer plastics as supplementary fuels in a circulating fluidised bed boiler specially designed for co-combustion with coal. Full emissions data on the 15% mixtures of individual plastics with coal are given, together with calculations of thermal efficiencies. Measurements by an independent body (British Coal Research Establishment) confirmed that the co-combustion of coal and plastic reduces some emissions compared with coal alone. Thermal efficiencies of around 80% were achieved and this heat was used effectively during the production of plastics. 7 refs. [Pg.102]

TFL is essentially a transition lubrication regime between EHL and boundary lubrication. A new postulation based on the ordered model and ensemble average (rather than bulk average) was put forward to describe viscosity in the nanoscale gap. In TFL, EHL theories cannot be applied because of the large discrepancies between theoretical outcomes and experimental data. The effective viscosity model can be applied efficiently to such a condition. In thin him lubrication, the relation between Him thickness and velocity or viscosity accords no longer with an exponential one. The studies presented in this chapter show that it is feasible to use a modi-Hed continuous scheme for describing lubrication characteristics in TFL. [Pg.77]


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Data used

Effective data

Self-evaluation using data effectively

Use, data

Useful Data

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