Application hydrogen profiling

An especially significant application of NRA is the measurement of quantified hydrogen depth profiles, which is difficult using all but a few other analytical techniques. Hydrogen concentrations can be measured to a few tens or hundreds of parts per million (ppm) and with depth resolutions on the order of 10 nm. 

NRA is an effective technique for measuring depth profiles of light elements in solids. Its sensitivity and isotope-selective character make it ideal for isotopic tracer experiments. NRA is also capable of profiling hydrogen, which can be characterized by only a few other analytical techniques. Future prospects include further application of the technique in a wider range of fields, three-dimensional mapping with microbeams, and development of an easily accessible and comprehensive compilation of reaction cross sections. 

Other applications include car rental, shared-car ownership or public transport -these transfer the risk of ownership of a vehicle with a new propulsion system away from the private person. Once established, these niche applications can help to raise the profile of the new technology, increase public acceptance and provide opportunities for feedback that can lead to technology improvement. Once their commercial viability in the niche market has been proved, the vehicles can expand into wider markets. Particularly suitable for introducing hydrogen (or other alternative fuels) are buses, fleet vehicles and rental vehicles (Smith, 2001). 

Sucrose Ethers. Being next to the anomeric center and intramolecularly hydrogen-bonded, the 2 -OH of sucrose is the most acidic, which means it is deprotonated first under alkaline conditions, and thus preferentially yields to etherification. Benzylation with NaH/benzylbromide in DMF, for example, results in an 11 2 1 mixture of 2 -(9-benzyl-sucrose (Figure 2.8) and its 1-0- and 3 -0-isomers. Because the former is readily accessible, it proved to be a versatile intermediate for the generation of 2 -modified sucroses, for example, the 2 -keto and 2 -deoxy derivatives as well as sucrosamine (2 -amino-2 -deoxy-sucrose), whose application profiles remain to be investigated. 

A quite different application of GDMS is the measurement of hydrogen and deuterium concentration, including depth profile analysis, e.g. in a gold electroplated layer on a CuSn substrate as described in reference.116 The relative sensitivity coefficient of hydrogen was evaluated by measurements of titanium standard reference material. 

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