Loss curve

Now, when these three parameters are known, Eq. (14.126) can be used for calculating the pressure losses in pneumatic conveying of wood chips in any other conditions. Also the pressure-loss curves for planning pneumatic conveying systems for wood chips can now be drawn. Figures 14.17 and 14.18 present examples of these. Similar curves can now be drawn for any pipe diameter D and for any air velocity by solving Eq. (14.126) numerically according to Fig. 14.16. 

Fig. 5.65 Dependence of the solar conversion efficiency (CE) on the threshold wavelength (Ag) for a quantum converter at AM 1.2. Curve 1 Fraction of the total solar power convertible by an ideal equilibrium converter with no thermodynamic and kinetic losses. Curve 2 As 1 but the inherent thermodynamic losses (detailed balance and entropy production) are considered. Continuous line Efficiency of a regenerative photovoltaic cell, where the thermodynamic and kinetic losses are considered. The values of Ag for some semiconductors are also shown (according to J. R. Bolton et al.)... 

Energy release and energy loss curves for an irreversible reaction in a flow reactor. 

However, the characteristics of point b with regard to temperature fluctuations are quite different. At this point the slope of the energy release curve is greater than the slope of the energy loss curve. If a small positive temperature fluctuation were to occur, one would be in a... 

If the temperature intercept of the energy loss curve lies between those corresponding to the... 

Fig. 7 Thermogravimetric weight loss curve (A) and subsequent IR spectra measured at the designated temperatures (B) 70°C, (C) 95°C, (D) 120°C, (E) 160°C, and (F) 180°C. A slight lag time exists between the TG weight loss and IR spectral acquisition due to the evolved gas being carried into the IR gas cell by the He carrier gas. Each IR spectrum is plotted on the same absolute intensity scale (Abs. units).

Again <5R follows from Equation (4.44) and Su from Equation (4.36). The equilibrium solutions for steady propagation are sketched in Figure 4.13. Only the loss curves depend on D. For D > Dq, two intersections are possible at s and u. The former, s, is a stable solution since any perturbation in temperature, 7b, will cause the state to revert to s. For example, if 7h > 7b S, Q / > <2R and dT/dt < 0 from Equation (4.45). Then 7), will decrease until 7bjS is reached. The intersection at u can be shown to be unstable, and therefore physically unrealistic. The point Q corresponds to the smallest diameter that will still give a stable solution. For D < Dq, dT/dt < 0 always, and any ignition will not... 

Once ignition has occurred in a mixture of fuel and oxidizer, propagation will continue, provided the concentrations are sufficient and no disturbance results in excessive cooling. The zeroth-order rate model is assumed to represent the lean case. Substituting the selected properties into Equation (4.43), the net release and loss curves are plotted in Figure 4.22 as a function of the flame temperature. The initial temperature of the mixture is 25 °C and fuel mass fractions are 0.05 and 0.03, representative of stoichiometric and the lower limit respectively. At this lower limit, we should see that a steady solution is not possible, and the calculations should bear this out. The burning rate is evaluated at the flame temperature, and 6K is found from Equation (4.44) with Su at the flame temperature... 

The right-hand side (RHS) of Equations (9.116) and (9.119) represent the net heat loss and the left-hand side (LHS) represents the energy gain. The gain and the loss terms can be plotted as a function of the flame temperature for both the diffusion and premixed flames as Semenov combustion diagrams. Intersection of the gain and loss curves indicates a steady solution, while a tangency indicates extinction. 

Figure 7.4 Dynamic mechanical loss curves of polyesters prepared from PET modified with 3 mol% of CHDM (relative to PCT)...

Note 3 A plot of tan 5 vs. temperature or frequency is known as a loss curve. 

Note 2 The term damping curve is sometimes used to describe a loss curve. 

Fig. 2.18 Slump loss at 21°C of superplasticized concretes with OPC and CAE or SNF ploymer-based admixtures. The figures on the slump-loss curves indicate the percentage of the superplasticizer active ingredient by mass of cement.

TGA. Unlike the previous two sets of molding compounds, the semiconductor grade novolacs investigated in this section do not differ solely in the presence or absence of a flame retardant. However, they are considered to be relatively equivalent. Weight loss measurements for the FR formulation, sample F, and the non-FR compound, sample G, are presented in Figure 7 for both nitrogen and air. Several differences are observed in the weight loss curves for these samples. 

The observation of these dielectric relaxation processes arising from carbonyl features, has also been reported by Tibbit and co-workers in plasma polytetra-fluoroethylene as well as other plama polymers. In measuring the dielectric loss tangents over a frequency range of 10 -10 Hz at temperatures of — 150 to 100 °C, they have demonstrated that the dielectric loss curves of plasma polymers derived from hydrocarbon and fluorocarbon monomers are very similar, but bear no resemblence to their conventionally polymerized counterparts. 

TGA. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) are other means to confirm the above structural models. Figure 4.4.8 shows the thermal analysis data for sample I. Curve (a) shows a TG datum of a mass loss about 22% after heating over 350°C. The derivative curve (b) of mass loss curve (a) clearly shows that there are at least four steps during the decomposition of the sample. This finding was further confirmed by the DTA data curve (c) shown in the same figure. It is clearly seen that there are four endothermic peaks. The DTA and TGA curves were similar for all samples. Note that the relative ratios of mass... 

Fig. 4.4.8 TGA and DTA result of sample 1. (a) Mass loss curve (b) Derivative curve of (a) (c) Differential thermal analysis curve. (From Ref. 10.)...

---