Panel density

Fig. 8.4 The s (upper panel) and sp (lower panel) density of states for different lattices in energy units of 0 with s = p = 0. The broken curves give the integrated density of states, provided the numbers on the vertical scale are multiplied by five for the s case and eight for the sp case respectively. (From Cressoni and Pettifor (1991).)...

The density profiles reveal density areas at both surfaces, with a lower density in the centre of the panel. The high surface density gives good bending strength and surface finishing characteristics. A low density in the core of the panel allows these surface properties to be achieved with an average panel density that is only 60-70% of that at the surface. For particleboard and OSB the profile between the peaks is a... 

Subsequent to publication of the original work done by Udvardy (17), a multiple correlation analysis of all replicates of the data points was conducted at Mobay. A set of regression equations was generated for each binder studied. Each equation predicted one of the board properties in terms of a number of processing variables including panel density. Correlation coefficients were 0.8 for internal bonds for the Mondur E-lll panels with all others being 0.9 or greater. 

Some of the predictive property equations were plotted vs. panel density for each binder with binder level and press time held constant at 2% and 5 minutes, respectively. Figure 10 shows that comparable MOR s are attainable with the Mondur E-lll at about a 10% lower density than with the phenolic. Aged M0R (Figure 11) determined in this study by MOR measurement after a two hour water boil (Canadian Standard CSA 0188-0M78) indicates the possibility of a savings of about 7-5-10% in density. Finally, Figure 12 shows that comparable internal bonds can be achieved by the isocyanate at up to 25% lower density vs. the phenolic resin. 

The purpose of this presentation has been to illustrate some advantages that are possible in the use of polymeric MDI as a binder for exterior grade wood composite panels. The data given have indicated the potential for savings in press time, press temperature, flake moisture content, resin level and panel density (as compared to conventional phenol-formaldehyde binders) in several types of such panels. 

Panel density (g/cm ) Measured wet (%) Measured dry (irreversible swelling) (%) Original IB, tensile perpendicular (kg/cm ) IB after a 2-h boil (kg/cm ) Cyclic test after five cycles measured (%)... 

For the industrial trial (Table 7) a rotary drum blender and an automated hot press were used to produce the boards. 30 m panels were manufactured using the formulation number 3. The board dimensions were 418 cm x 192 cm with 16 mm thickness, for a target density of 670 kg/m. The internal bond (IB) strength of the boards was tested immediately after panel cooling as well as after 24 h (Table 7) using the method described in the EN 319 1993-08 standard [6], while the panel density was measured according to the EN 323 1994 standard [7]. 

Figure 1. Density profile of a high density plywood panel pressed at the higher temperature. The panel density is so high that the interphases are not visible as the rest of the panel has a density as high as the interphases. Average panel density = 1203 kg/m, 5 plies, veneers stacked with the wood grain in the same direction, 250°C, 60 min press time, veneers pressed dry.

Figure 3.13 Spin-up (upper panel) and spin-down (lower panel) density of occupied (KS) electron states for the lowest-energy isomer of Ni6. Computations have been performed within DFT-LSD-GGA. The computed Kohn-Sham eigenvalues have been convoluted with a 0.15-eV-wide Gaussian (after P. Ballone and R. O. Jones, unpublished work)...

Moduli of elasticity of soil layers have been investigated experimentally. Effective densities of structure parts are based on the analysis of variations of masses of panels and those of floor live loads. Probability distribution types for all considered parameters have been determined (beta-type for soil, normal for panel densities, log-normal for live load). Corresponding mean values, standard deviations and coefficients of variation have been computed. Mean values of modulus of elasticity of soil layers with indicated standard deviations are shown in Figure 3 (Bajer et al. 2012). 

Figure 9 Left panel density profile of a liquid phase with a drying layer of a thickness L near a weakly attractive surface. The thickness of an interface between the drying layer and solid surface and the thickness of a Uquid-vapor interface are controlled by the bulk correlation lengths and in respective fluid phases. Right panel a drying layer is completely bound to the wall, two interfaces merge together, giving gradual density depletion, controlled by. ...

Figures Reconstruction of the W(OOl) surface. Top view of the bulk-like, unreconstructed W(OOl) surface (open circles), c(2 x 2) reconstruction as obtained from energy mininuzation using first principles quantum mechanical calculations (full circles) lower left panel total energy as a function of the lateral displacement, j, of the surface atoms, lower right panels density of states of the surface layer of an unreconstructed p(l x 1) and reconstructed c(2 x 2) W(OOl) surface (After Fu et al. )...

Thermal stability at elevated tenperatures of PET containers is improved with the inclusion of heat-set temperatures. Furthermore, the inclusion of RPET blends also demonstrates improved thermal stability at hot-fill temperatures at 85 C. An increase in heat-set temperature demonstrates an increase in the average panel density, hence suggesting an increase in the initial erystallinity of the PET panel. 

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