Cryogenic materials

An elementary introduction to chemistry is given in Chapter 3 this serves only to provide background and for more advanced consideration reference will be necessary to specific text books, e.g. as listed in the Bibliography. A brief discussion of the relevance of physicochemical principles to hazard identification is given in Chapter 4. Relevant toxic and flammable properties, and summaries of appropriate precautions to cater for them during handling, use and disposal, are provided in Chapters 5 and 6, respectively. Reactive hazards are discussed in Chapter 7. The special problems with cryogenic materials and chemicals under pressure, typified by compressed... 

Table 8.3 General precautions with cryogenic materials...

More data on polymers and other fibre-reinforced polymers can be found in the proceedings of various ICMC (International Cryogenic Materials Conference) meetings devoted to non-metallic materials and composites at low temperatures [113-117] and some special issues of the journal Cryogenics [118-120]. 

Advances in Cryogenic Engineering Transactions of the International Cryogenic Materials Conference -ICMC, vol. 51-52, Keystone, Colorado, 29 August-2 September 2005, ed. by Balachandran, U. (Balu), Springer, New York (2006)... 

Cryogenic materials Established data on properties of weld and base metals in LHj. Hydrogen diesel engine Tested a 100 kW single cylinder engine. 

CRYOGENIC MATERIALS. Those metals and alloys usable in structures operating at very low temperature, and usually possess improved strength properties at these temperatures. See also Cryogenics. 

Cryogenic materials and the surfaces they cool can cause severe cold bums if they are allowed to contact the skin. Thick gloves and a face shield may be needed when preparing or using some cold baths. 

The suitability of a water spray for application to releases composed of water-soluble materials is specific to the particular material in question. If applied to cryogenic materials, a water spray can cause the material to heat and violent boiling can result. Therefore, it is prudent to understand the properties of the material in question. Key considerations include the flash point, specific gravity, viscosity, and solubility of the material, the temperature of the water spray, and the temperature of the hazardous material (NFPA 15, 1990). 

Equation (5.2) indicates that the time vapor is advected downwind will increase as zt (height of vapor containment box) increases, as this increases the time to fill the vapor box. This additional time allows for the effects of decreasing rates of conductive heat transfer from the dike floor for cryogenic materials, or decreasing convective mass transfer for materials with boiling points that are higher than ambient temperatures, to take effect. 

Beakers and Flasks. Beakers and flasks are the least effective containers for cryogenic materials because there is no insulation whatsoever. However, if the coolant is only water, ice, or a salt/ice mixture, not much insulation is required. There is little concern for rapid material loss with these coolant solutions because they are easy and inexpensive to replace. In addition, it is (usually) safe to pick up these containers with your bare hands. If any ice forms on the sides of a container, it is simple to use gloves or tongs to pick up the beaker or flask and prevent possible skin damage. 

Because companies that supply compressed gasses also commonly supply cryogenic materials, I ve combined these two chapters sources. 

There are many advantages to the use of NH3 as hydrogen source for vehicular fuel cell vehicle applications. However, a major drawback is ammonia s extreme toxicity and adverse health effects. By complexing NH3 with diborane, a stable, non-toxic and non-cryogenic material (H3BNH3) can be prepared. This ammonia-borane complex is stable in water and ambient air and when heated liberates H2 in a sequence of reactions between 137°C and 400°C that reaches about 20% of the initial mass of H3BNH3. Successfiil implementation of ammonia-borane as a potential future transportation fuel, however, requires new chemical techniques and/or processes for its s mthesis that promise substantial reduction in its production costs. 

Cryogenic Materials Establishment of methods for materials evaluation Development of structural materials for cryogenic tanker and storage plants... 

Reported at International Conference on Cryogenic Materials, Chicago, May 1987, and also at Japan-U.S. Symposium on High High Temperature Supercondctivity, Tokyo, October 1987. 

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