Measuring the hydrogen content in materials is important both for research and for various applications in material and surface sciences, such as hydrogen embrittlement of steel, controlled thermonuclear reaction first wall studies, and changed material properties caused by dissolved hydrogen. Hydrogen is the most difficult atomic species to analyze by traditional methods, but nuclear physics methods are particularly suited for this purpose. President of the Uzbek SSR Academy of Sciences P.K. Khabibullaev and Professor B.G. Skorodumov discuss in this book the characteristics of these methods,...