Hydrogenation distribution

This stress-strain behavior is consistent with the optic metallographic data which evidenced partial redistribution of hydrogen over the powder particles when the compacting temperature was increased to 400°C and uniform hydrogen distribution on additional annealing or during plastic deformation at T > 500°C. 

The observed hydrogen distribution is consistent with mechanism (8.44AB). 

To overcome the shortcomings of interpreting the SIMS data on hydrogen distribution in anodic aluminas, Lanford et al214 have... 

The onboard hydrogen supplied from organic chemical hydrides will be utilized well in the ICE vehicles. Even for stationary use of hydrogen, distribution of organic chemical hydrides will play an important role at stations or sites, where waste heat at modest temperatures is dissipated in vain without chemical recuperation. 

Fig. 10. Hydrogen distribution in c-Si after annealing at the indicated temperature. The solid line indicates the initial (as implanted) distribution. [Courtesy of C.W. Magee and C.P. Wu]...

More complicated is the evolution of the hydrogen distribution in situations where the electrostatic potential distribution is affected not only by... 

Recent channeling studies have been interpreted to indicate H—B pairs with hydrogen distributed between both the BC and Si—AB sites, with a preference for the BC site at low temperatures. (Marwick et al., 1987, 1988 Bech Nielsen et al., 1988). The boron is estimated to be off the substitutional site by roughly 0.2-0.3 A. This is consistent with the PAC measurements of the similar H—In pair, where the Si—AB site is favored at higher temperatures (T > 150 K), but the BC site is favored at lower temperatures (Wichert et al., 1987, 1988 Wichert, 1988). Also from the PAC studies, the H—In defect is found to anneal with a dissociation barrier estimated to be about 1.3 eV (Wichert et al., 1987). 

Valves, the use of which may be necessary for the safe operation of a hydrogen distribution system, shall be checked and serviced, including lubrication where necessary, at sufficiently frequent intervals to assure their satisfactory operation. Examination shall include checking of alignment to permit use of a key or wrench and clearing from the valve box or vault any debris that would interfere with or delay the operation of the valve. Valves in hydrogen service shall be checked and serviced at least annually. 

Each operating company having a hydrogen distribution system shall set up, in its operating and maintenance plan, a provision for the making of periodic leakage surveys on the system. 

Chapter 12 discusses and analyses the different options for hydrogen distribution -pipelines and trailers (including liquefaction) - from a technical and economic point of view, in the same way as the hydrogen production technologies in Chapter 10. Further, different hydrogen refuelling station concepts are described and the necessity for the development of codes and standards addressed. 

Hydrogen distribution Table 12.2. Technoeconomic data of hydrogen liquefaction... 

Mintz, M., Molburg, J., Folga, S. and Gilette, J. (2002). Hydrogen Distribution Infrastructure. Research paper. Argonne Argonne National Laboratory, Transportation Technology R D Centre. 

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