Surface roughness, data

Table 12-1 shows some characteristic surface roughness data for various types of finish encountered in technological practice. The... 

The surface roughness data of the polymer pins were R 1.3 im and R c=s 0.2 urn. The tests were performed at very low sliding speeds in order to eliminate friction-induced thermal effects. The following experimental conditions were used contact oressure p = 3.2 N/mm sliding velocity v = 2.4 x 10 7 m/s ambient temperature T = 23 C relative humidity 50%. 

Figure 5. SEM cross section images and surface roughness data of the coatings prepares by two elemental targets and the singie alloying target, respectively.

Figure 5.10. The effect of mold surface treatment with triazine dithiol containing perfluori-nated groups on its surface roughness. [Data Mori, K. Sasaki, Y Hirahara, H. Oishi, Y, J. Appl. Polym. Sci., 90, 2549-56, 2003., 2557-71, 2003.]...

Table 1. D-PP film surface roughness data from AFM... 

In the context of the structural perturbations at fluid-solid interfaces, it is interesting to investigate the viscosity of thin liquid films. Eaily work on thin-film viscosity by Deijaguin and co-workers used a blow off technique to cause a liquid film to thin. This work showed elevated viscosities for some materials [98] and thin film viscosities lower than the bulk for others [99, 100]. Some controversial issues were raised particularly regarding surface roughness and contact angles in the experiments [101-103]. Entirely different types of data on clays caused Low [104] to conclude that the viscosity of interlayer water in clays is greater than that of bulk water. 

Convection Heat Transfer. Convective heat transfer occurs when heat is transferred from a soHd surface to a moving fluid owing to the temperature difference between the soHd and fluid. Convective heat transfer depends on several factors, such as temperature difference between soHd and fluid, fluid velocity, fluid thermal conductivity, turbulence level of the moving fluid, surface roughness of the soHd surface, etc. Owing to the complex nature of convective heat transfer, experimental tests are often needed to determine the convective heat-transfer performance of a given system. Such experimental data are often presented in the form of dimensionless correlations. 

Fig. 8. X-ray reflection diagram of a thin polystyrene film on float glass [160]. The reflectivity R is plotted against the glancing angle . The film is spin coated from solution. A model fit (dashed line) to the reflectivity data is also shown where the following parameters are obtained film thickness = 59.1 0.1 nm, interface roughness glass-polymer = 0.4 0.1 nm, surface roughness polymer-air = 0.6+1 nm, mean polymer density = 1.05 + 0.01 g/cm-3. The X-ray wavelength is 0.154nm...

The dependence of the C,E curves for a solid metal on the method of electrode surface preparation was reported long ago.10 20 67 70 219-225 in addition to the influence of impurities and faradaic processes, variation in the surface roughness was pointed out as a possible reason for the effect.10 67,70 74 219 For the determination of R it was first proposed to compare the values of C of the solid metal (M) with that of Hg, i.e., R = C-M/c-Hg 10,74.219-221 data at ff=0 for the most dilute solution (usually... 

The influence of compressibility was assessed by varying the Mach number in the range 0 < Ma < 0.38, while Kn and ks/H were kept low. Friction factor data were reported only with Ma < 1 at the exit, to ensure the flow rate was controlled by viscous forces alone. A mild increase in the friction factor (8%) was observed as Ma approached 0.38. This effect was verified independently by numerical analysis for the same conditions as in the experiment. The range of relative surface roughness tested was 0.001 < ka/H < 0.06, yet there was no significant influence on the friction factor for laminar gas flow. 

The word deterministic" means that the model employs a specific surface geometry or prescribed roughness data as an input of the numerical procedure for solving the governing equations. The method was originally adopted in micro-EHL to predict local film thickness and pressure distributions over individual asperities, and it can be used to solve the mixed lubrication problems when properly combined with the solutions of asperity contacts. 

In this section, two t5q)ical engineering surfaces, a ground surface and a shaved surface, are employed for the comparison. The original roughness data were measured with an optical profilometer, but the roughness amplitude has been rescaled for the convenience of computation. In simulations, a relatively small load of 50 N is applied to guarantee that asperities will not be completely flattened while other operation conditions are listed in Table 4. 

According to the experimental data presented above, the dependence of the contact ratio a on the test conditions and material properties, such as viscosity, speed, surface roughness, pressure, and elastic module can be descried by an exponential function as ... 

TEM micrographs of a neat PS particle (a) and those coated with one to five Si02/PDAD-MAC multilayers (b-f). The nncoated PS latices are spherical and feature a smooth surface (a). The presence of SiOi/PDADMAC mnltilayers on the PS latices result in both an increase in surface roughness (dne to SiOi) and a systematic increase in the diameter of the PS latices (b-f). Consistent with the SPLS and SEM measnrements, the PS particles are homogeneously coated with nanoparticles. The TEM data (Fig. 6) yield an average diame-... 

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