Transverse coefficients

Liou et al. [13] have measured the effect of absorbed moisture on the thermal expansion coefficients of carbon fibre epoxy laminates. Moisture lowers the transverse coefficient, but has little effect on Oi at room temperature. Failure in some epoxy laminates used to make multilayer PCBs has been traced to high z-axis thermal expansion stresses on marginal plated-through holes. Moisture is a factor, and complete drying can sometimes eliminate the problem [14]. 

The transverse coefficient Dy has a standard value of OAShu for straight, uniform reaches. However, Ward (99), Chang (10), and others note that bends increase this to as high as 2hu if transverse velocities are not included in the equation. Prych (75) provides a means of adjusting the value of Dy to account for added spreading due to bouyancy in an initial zone. Sumer (89) notes increases of Dy in stratified flows, although the values are still below 2/im. ... 

For the following composite materials, consisting of aligned, continuous fibres in a polymer matrix, estimate the axial and transverse coefficients of linear thermal expansion (percentages given are fibre volume fractions)... 

Figure 6.3 shows the longitudinal and the transverse coefficients of thermal expansion (the CTEs) predicted using the Rosen-Hashin model. The component properties of the composite used are ... 

Table 4.4 Swelling coefficient P %) (per 1 % moisture weight gain) Py, P, and are volumetric, longitudinal, and transverse coefficients, respectively...

Here 1111 and are the longitudinal and transverse coefficients of the viscosity of a uniaxial anisotropic liquid which are correlated by linear correlations with the Miesowich and Ericksen-Leslie viscosity coefficients. In addition, these coefficients would be equal to Miesowich viscosities t j and 1)3 if there is an ideally oriented solution in the gap. However, it is practically impossible to obtain the ideal orientation in shear flow. 

Thermal conductivity, in plane Thermal conductivity, transverse Coefficient of thermal expansion, in plane transverse Glass transition (T ... 

Multidimensionality may also manifest itself in the rate coefficient as a consequence of anisotropy of the friction coefficient [M]- Weak friction transverse to the minimum energy reaction path causes a significant reduction of the effective friction and leads to a much weaker dependence of the rate constant on solvent viscosity. These conclusions based on two-dimensional models also have been shown to hold for the general multidimensional case [M, 59, and 61]. 

If the diffusion coefficient of species A is less tlian tliat of B (D < D ) tlie propagating front will be planar. However, if is sufficiently greater than tire planar front will become unstable to transverse perturbations and chaotic front motion will ensue. To understand tire origin of tire mechanism of tire planar front destabilization consider tire following suppose tire interface is slightly non-planar. We would like to know if tire dynamics will tend to eliminate this non-planarity or accentuate it. LetZ)g The situation is depicted schematically in figure... 

For annuli containing externally Hnned tubes the heat-transfer coefficients are a function of the fin configurations. Knudsen and Katz (Fluid Dynamics and Heat Transfer, McGraw-Hill, New York, 1958) present relationships for transverse finned tubes, spined tubes, and longitudinal finned tubes in annuli. 

High Fins To calculate heat-transfer coefficients for cross-flow to a transversely finned surface, it is best to use a correlation based on experimental data for that surface. Such data are not often available, and a more general correlation must be used, making allowance for the possible error. Probably the best general correlation for bundles of finned tubes is given by Schmidt [Knltetechnik, 15, 98-102, 370-378 (1963)] ... 

Of greater interest in recent years have been the peculiar piezolectric properties"" of polyfvinylidene fluoride). In 1969 it was observed" that stretched film of the polymer heated to 90°C and subsequently cooled to room temperature in a direct current electric field was 3-5 times more piezoelectric than crystalline quartz. It was observed that the piezolectric strain coefficients were higher in the drawn film and in the normal directions than in the direction transverse to the film drawing. 

Low smoke emission (roughly comparable to that of a polycarbonate). Very low coefficient of thermal expansion in the flow direction (0-15 cm/ cm/°C) but correspondingly higher in the transverse direction (27-76 cm/ cm/°C). 

Moisture and Humidity International Symposium on Moisture and Humidity. Washington, DC, 1985. R. G., Wylie, T. Lalas. Accurate psychrometer coefficients for wet and ice-covered cylinders in laminar transverse air streams. In Moisture and Humidity 1985 Measurement and Control in science and Industry, pp. 37-56. 

E, E2, Eg = Young s (extension) moduli in the 1-, 2-, and 3-directions V j = Poisson s ratio (extension-extension coupling coefficient), i.e., the negative of the transverse strain in the j-direction over the strain in the i-direction when stress is applied in the i-direction, I.e.,... 

Figure 5-10 Transverse Deflection Coefficient versus Principal Stiffness Ratio (After Ashton [5-11 ])...

The Peclet numbers decrease when the dispersion coefficients increase. In the Reynolds number range of 10-200, in a packed bed of pellets, Peii = 2 and PeH = 0.5 (119, 120). The dispersions in the transverse... 

Transverse Rupture Strength 240-390 MPa Coefficient of Friction 0.25 (on tool steel, 50% humidity)... 

Table I reports the observed NMR linewidths for the H/3 protons of the coordinating cysteines in a series of iron-sulfur proteins with increasing nuclearity of the cluster, and in different oxidation states. We have attempted to rationalize the linewidths on the basis of the equations describing the Solomon and Curie contributions to the nuclear transverse relaxation rate [Eqs. (1) and (2)]. When dealing with polymetallic systems, the S value of the ground state has been used in the equations. When the ground state had S = 0, reference was made to the S of the first excited state and the results were scaled for the partial population of the state. In addition, in polymetallic systems it is also important to account for the fact that the orbitals of each iron atom contribute differently to the populated levels. For each level, the enhancement of nuclear relaxation induced by each iron is proportional to the square of the contribution of its orbitals (54). In practice, one has to calculate the following coefficient for each iron atom ...

Fig. 1.28. The change in sticking coefficient of atoms of hydrogen during doping of film of ZnO by atoms of Ag (/), Zn (2) and applying the transverse electric field to the film O) [198, 199]...

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