Substrate hardness

With PdCl2(76)2 the conversion of l-chloro-2-nonene was quantitative whereas with the non-polar PdCl2[P(nBu)3]2 the lipophilic substrate hardly came into contact with the hydrophilic reductant HCOONa and the conversion was low (26%).215... 

Hardness. Hardness of the adhesive or sealant may be used as an indication of cure. It may also be used as a quality control check on certain substrates. Hardness can be determined in several ways (1) resistance to indentations, (2) rebound efficiency, and (3) resistance to scratching or abrasion. The first method is the most commonly used technique. 

No information seems to exist about the formation and performance of films on very soft materials, but down to the lowest hardnesses which are of interest for bearing use, i.e. about 200 VPN, the wear life of the molybdenum disulphide tends to improve as substrate hardness decreases, although Tsuya s findings were less... 

Reid and Schey studied the role of substrate composition and other factors in the formation and performance of films on various metal substrates, including copper, aluminium, titanium and mild steel, tested against themselves and against an alloy steel. They used a twist-compression test to assess performance, and concluded that substrate hardness and composition had the greatest influence on film formation and life. They believed that film formation and especially durability are improved by chemical reaction if a substrate, such as copper or iron, has a strong tendency to react to form a sulphide, provided that the reaction kinetics are favourable. However, they found no direct evidence of reaction or of sulphide formation. Their conclusions were based on the fact that the durability of the films was found to be in the sequence aluminium, titanium, iron, copper, which is the same as the order of the free energies of formation of their sulphides. 

Lancaster, J.K., The Influence of Substrate Hardness on the Formation and Endurance of Molybdenum Disulphide Films, Wear, 10, 103, (1967). 

Substrate Hardness HVl (Each 9 Measurements) Critical loads for cohesive failure in scratch tests [N] (each 9 scratch tests)... 

The eastern Baltic Proper coast consists mainly of highly mobile sandy substrates. Hard bottom, suitable for macroalgae colonization, is very rare in its southern parts. Further north, off the coast of Latvia and Estonia, hard bottom becomes available again and macrophytes thrive there. 

The initial monomers, dipropargyl ethers of bis(s)phenols and their polymers, are available in a one-step easy preparation in quantitative yield. They are suitable for industrial production in large scale and potentially available at a low price. The coatings based on these linear polymers require low energy for curing. Their radiation cure is completed for several seconds in the absence of a photosensitizer at room temperature, whereas thermal cure proceeds for half an hour at 100°C. The initial unoptimized properties of these coatings appear very attractive. They exhibit excellent adhesion to metal substrates, hardness, flexibility, impact resistance, good solvent resistance, low water absorption, and... 

Figure 6 shows the hardness of thin films measured by a nanoindenter. The film on the MgO substrate showed a higher hardness than that of the film on Si substrate in 5r = 0 and 10%. In the polycrystalline thin film on Si substrate, conventional result that hardness increases with increasing Si content was confirmed. The hardness was increased from 23 to 29 GPa. Furthermore, in the thin film on MgO substrate, hardness increases with increasing Si content. The hardness was increased from 29 to 36 GPa. This result could be supposed the effect of the obstruction of dislocation movement (solid solution hardening) for solubility of Si atoms in the CrN lattice. As the result, Cr-Si-N thin film on MgO substrate (5r = 10% Si content = 5.0 at.%) showed the highest hardness 36 GPa. 

Fig. 8 shows the hardness depth profiles of the treated specimens. The carburized 8C specimen developed a maximum hardness of about 500 Hv, which is much lower than the hardnesses of 1230 to 1588 Hv for other three nitrided and nitrocarburised specimens. The nitrided layer of the 8N specimen produced a hard layer of 1588 Hv with an abrupt layer-core interface, while the 8C carburizing produced a gradually decreased hardness profile. Two combined carburized and nitrided specimens, 8(C + N) and 4C-4N developed a similar tendency to bulge in hardness profiles at inner carburized layer as shown in Fig. 7. The most gradual decrease in hardness from 1230 Hv level to substrate hardness was displayed by the 4C-4N specimen.

No smell Low solubility of many nonpolar substrates Hard to collect in case of spills ... 

Equation (4.13) produces the observed experimental effect of rising slightly for small indentation diagonal lengths before falling as the indent diagonal increases. Better agreement with observed hardness versus film thickness curves is achieved when Hy V] is replaced by fca Vi/V, + V2 in order to emphasize the substrate hardness. 

Coating Substrate Substrate Hardness (GPa) Thickness (nm) Deposition Technology Deposition Temperature CQ... 

Among these enzymes, Novozyme 435 was the most suitable for the procedure. PS-CI and TLIM hardly catalyzed the reaction, although RMIM catalyzed it relatively well. The difference in the recognition of the substrate by lipases is probably in accordance with the difference in the substrate orientation in the active center (Pleiss et al, 1998). With one possible exception, the substrates easily accessed the active center of Novozyme 435. Additionally, it is suggested that the substrates hardly accessed the active sites of RMIM, PS-CI, and TLIM. 

Hypalon 30 For rigid substrates Hard, glossy films. Good oil resistance... 

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