Elastic recoil

Forward recoil spectrometry (FRS) [33], also known as elastic recoil detection analysis (ERDA), is fiindamentally the same as RBS with the incident ion hitting the nucleus of one of the atoms in the sample in an elastic collision. In this case, however, the recoiling nucleus is detected, not the scattered incident ion. RBS and FRS are near-perfect complementary teclmiques, with RBS sensitive to high-Z elements, especially in the presence of low-Z elements. In contrast, FRS is sensitive to light elements and is used routinely in the detection of Ft at sensitivities not attainable with other techniques [M]- As the teclmique is also based on an incoming ion that is slowed down on its inward path and an outgoing nucleus that is slowed down in a similar fashion, depth infonuation is obtained for the elements detected. 

Elastic recoil spectrometry (ERS) is used for the specific detection of hydrogen ( H, H) in surface layers of thickness up to approximately 1 pm, and the determination of the concentration profile for each species as a function of depth below the sample s surfece. When carefully used, the technique is nondestructive, absolute, fast, and independent of the host matrix and its chemical bonding structure. Although it requires an accelerator source of MeV helium ions, the instrumentation is simple and the data interpretation is straightforward. 

The energy scale of an elastic recoil spectrum provides information about the mass of the recoiling species, and about the depth within a sample at which the scattering took place. 

As with RBS, the simplest and most precise measurement that ERS can provide is the absolute measure of total hydrogen content ( H and/or H) within a surface layer or film of thickness less than a few thousand angstroms. When the layer is thin, this is determined from the total number of events, or yield Ysummed over the elastic recoil spectral peak. The yield may be expressed as... 

Elastic Recoil Detection Analysis Glow discharge mass spectrometry Glow discharge optical emission spectroscopy Ion (excited) Auger electron spectroscopy Ion beam spectrochemical analysis... 

Because the cross-sections for nuclear reaction are usually lower than the cross-sections for elastic scattering of projectiles used in RBS or in elastic recoil detection analysis (ERDA), higher currents must be used to obtain comparably high intensity in... 

Elastin confers extensibihty and elastic recoil on tissues. Elastin lacks hydroxylysine, Gly-X-Y sequences, triple hehcal stmcture, and sugars but contains desmosine and isodesmosine cross-links not found in collagen. 

The use of nuclear techniques allows the determination of C, N, H, O, and heavier contaminants relative fractions with great accuracy, and of the elements depth profile with moderate resolution (typically 10 nm). Rutherford backscattering spectroscopy (RBS) of light ions (like alpha particles) is used for the determination of carbon and heavier elements. Hydrogen contents are measured by forward scattering of protons by incident alpha particles (ERDA) elastic recoil detection analysis [44,47]. 

Diffuse reflectance infrared Fourier transform spectroscopy deuterium triglycine sulphate energy compensated atom probe energy dispersive analysis energy-loss near edge structure electron probe X-ray microanalysis elastic recoil detection analysis (see also FreS) electron spectroscopy for chemical analysis extended energy-loss fine structure field emission gun focused ion beam field ion microscope... 

Describe the role of elastic connective tissues in elastic recoil of the lungs as well as in lung compliance... 

---