Attack, resistance

Both industry experience and research work indicate that postweld heat treatment (PWHT) of chromium-molybdenum steels in hydrogen service improves resistance to high temperature hydrogen attack. The PWHT stabilizes alloy carbides. This reduces the amount of carbon available to combine with hydrogen, thus improving high temperature hydrogen attack resistance. 

A5. T. Ishiguro, K. Kimura, T. Hatakeyama, T. Tahara and K. Kawano, Effect Metallurgical Factors on Hydrogen Attack Resistance in C-0.5Mo, presented at the Second International Conference on Interaction with Hydrogen in Petroleum Industry Pressure Vessel and Pipeline Service, The Materials Properties Council, Inc., Vienna, Austria, October 19-21,1994. 

Proteins differ greatly in their intrinsic susceptibility to proteolytic attack. Resistance to proteolysis seems to be dependent upon higher levels of protein structure (i.e. secondary and tertiary structure), as tight packing often shields susceptible peptide bonds from attack. Denaturation thus renders proteins very susceptible to proteolytic degradation. 

Hence, it can be assumed that the inhibition of dark process, Fc7H202, occurred due to the formation of Fe -complexes resulting with a lack of OH radicals in bulk produced through bulk Fenton reaction, while the mineralization efficiency of UV/Fe°/H202 process was inhibited by the formation of large amounts of OH radical attack resistant organics acids. That is in accordance with the observation from Figure 7, where the appearance of new peaks occurred after 30. minute of treatment process. 

Immune to intergranular attack resistant to oxidizing environments... 

Biological attack resistance Resistant Most resistant Least resistant ... 

Softens at 210°. mp 223°. Can withstand a temp or 100° for long periods of time, dj 1.14. Moisture regain is about 4%. Swelling is low if steeped in water and then centrifuged its volume increases by about 13-14%. Immune to microbiological attack. Resistant to most org chemicals, but dissolved by phenol, cresol, and strong acids. 

More resistant than porcelain to all forms of chemical attack. Resistant up to 1600°C to most acid fluxes Vessels for metallic, alloy, salt and glass melts... 

The biochemical bases for the terpenoid-mediated interactions of conifers with bark beetles and their fungal symbionts is understood in broad outline. Resistance to colonization ultimately resides In the species-specific arsenal of terpenoids which can be snistered in response to an attack. Resistant... 

Carbonaceous materials exhibit excellent thermal conductivity, volume stability, chemical attack resistance, and thermal shock resistance, making them a valuable component for refractory applications. However, they must be properly cooled to assure long-term survivability in metallurgical applications. 

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