Secondary neutron mass spectrometry

Other technique—for example, dynamic secondary ion mass spectrometry or forward recoil spectrometry—that rely on mass differences can use the same type of substitution to provide contrast. However, for hydrocarbon materials these methods attain a depth resolution of approximately 13 nm and 80 nm, respectively. For many problems in complex fluids and in polymers this resolution is too poor to extract critical information. Consequently, neutron reflectivity substantially extends the depth resolution capabilities of these methods and has led, in recent years, to key information not accessible by the other techniques. 

Lorey D II, Morrison G, Chandra S (2001) Dynamic secondary ion mass spectrometry analysis of boron from boron neutron capture therapy drug in co-cultures single-cell imaging of two different cell types within the same ion microscopy field of imaging. Anal Chem 73 3947-3953. doi 10.1021/ac0103266... 

For all these specialty polymers, deuterium can be used as a label on one or the other monomer. Deuterium labeling allows the use of techniques based on ion detection such as forward recoil spectrometry (FRES), nuclear reaction analysis (NRA) or secondary ion mass spectrometry (SIMS). If a high-resolution depth profile of the interfacial region is needed, neutron reflectivity can also be used. The main drawback of that approach is the cost of the deuterated polymers while deuterated styrene and methyl methacrylate are expensive but commercially available, other monomers need to be synthesized and the cost can be quite prohibitive. 

Lub, L, van Vroonhove, F.C.B.M., Bruninx, E., and Benninghoven, A., "Interaction of Nitrogen and Ammonia Plasmas with Polystyrene and Polycarbonate Studied by X-Ray Photoelectron-Spectroscopy, Neutron-Activation Analysis and Static Secondary Ion Mass-Spectrometry," Polymer 30, 40-44,1989. 

The reptation dynamics and the interface structure relations in Table 2 have been demonstrated experimentally by a series of interdiffusion experiments with selectively deuterated HDH/DHD polymer interfaces using dynamic secondary ion mass spectroscopy (DSIMS - see Secondary ion mass spectrometry) and neutron reflectivity. The scaling laws for interdigitation and the complete concentration profiles for Rouse and reptation dynamics have also been calculated. ... 

Low dislocation-density samples were diffused with Ga at 700 to llOOC, and the resultant profiles were determined by using secondary ion mass spectrometry or neutron activation methods. The results could be described by ... 

Current Status of Munitions Assessment and Processing System (MAPS), Portable Isotopic Neutron Spectroscopy (PINS), Secondary Ion Mass Spectrometry (SIMS), and Raman Spectroscopy Ed Doyle and Bill Brankowitz PMNSCM... 

There are other modern spectroscopic methods such as X-ray photoelectron spectroscopy (XPS), small angle neutron scattering (SANS), Raman spectroscopy (RS), electron spinning resonance (ESR) and nuclear magnetic resonance (NMR). These techniques are well known in the membrane field. Static secondary ion mass spectrometry (SSIMS), energy dispersive X-ray spectroscopy (EDS), laser confocal scanning microscopy (FCSM) and environmental scanning electron microscopy (ESEM) can also be added to new microscopic methods to characterize the membranes [84]. 

Atomic mass is the mass of an atomic particle, i.e. a specific isotope. When expressed in unified atomic mass units, this is called the relative isotopic mass. The word relative is added to denote the fact that all masses are scaled to that of the isotope when set to 12 u. Nominal isotope masses are more commonly used when applying analytical techniques such as Secondary Ion Mass Spectrometry (SIMS) because this significantly simplifies matters without detracting from the information content needed. This represents the number of protons and neutrons within the nucleus, i.e. equal to the atomic mass number (A). Note It was the mass spectrograph constructed by Aston in 1919 (the first mass spectrometer from which SIMS evolved as covered in Section 1.2.1) that confirmed the existence of the isotopes, and allowed for the first time, an accurate means of measuring their relative mass (that relative to H, 0, or more recently C) and distribution. 

The experimental methods to estimate the thickness and structure of the interphase region in polymer-polymer systems were re-viewed. ° ° Using various physical principles, it became possible to evaluate both the thickness and density profile of many systems. The most informative methods are based on the neutron reflection from the interface between two polymers.Ellipsometry and secondary ion mass spectrometry, IR-spec-trosco ), and inverse gas chromatography also can be used, among other meth-- t i example, the segment density profile was estimated for... 

Rosenberg, R. J., ZiUiacus, R., Lakomaa, E. L., Rautiainen, A., and Makela, A. (1996). Study of CdTe/CdS-thin films by isotope dilution, neutron activation analysis, inductively coupled plasma mass spectrometry and secondary ion mass spectrometry. Fresenius J. Anal. Chem. 354(1), 6. 

Several books are devoted to IBA techniques, and there are excellent and extensive reviews that cover the roles of IBA techniques in polymer science. The purpose of this section is therefore not to provide an exhaustive survey of literature where IBA has been applied to polymers, but to provide polymer scientists with answers to questions like What can IBA do for me and Why would I use IBA and not X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS), or neutron reflectivity The limitations of ion beam techniques will also be reviewed to address the equally important question, When should I not use IBA and hopefully form a practical guide to what one might achieve with IBA. 

Neutron Activation Analysis X-Ray Fluorescence Particle-Induced X-Ray Emission Particle-Induced Nuclear Reaction Analysis Rutherford Backscattering Spectrometry Spark Source Mass Spectrometry Glow Discharge Mass Spectrometry Electron Microprobe Analysis Laser Microprobe Analysis Secondary Ion Mass Analysis Micro-PIXE... 

The mass spectrum of SOAz is shown Fig. 38 and its pattern is quite different from that of MYKO 63 in fact we no longer observe the fall of the Az leaves which characterizes any mass spectrum within the MYKO 63 series. The base peak is at m/z 320 and there are very few other secondary peaks till m/z 50. No chlorinated impurity could be detected either by mass spectrometry or by neutron activation. 

Rutherford backscattering spectroscopy Scanning electron microscopy Secondary ion mass spectroscopy Single crystal X-ray diffraction Small angle X-ray and neutron scattering Spark source mass spectrometry Transmission electron microscopy Voltametry... 

Variations in isotopic abundances that are caused by nuclear reactions induced by cosmic rays are most commonly utilized in cosmic ray exposure dating, but this employs isotopes that are measured by either accelerator or noble gas mass spectrometry [28, 29]. In fact, there are only a very limited number of elements that are suitable for the study of cosmogenic isotopic variations, which can be readily analyzed by either TIMS or MC-ICP-MS [28]. The most important application of these techniques are studies of the secondary neutron fluxes that are generated by (primary) cosmic rays. Such measurements aim to detect anomalies in Sm, Gd, and Cd isotopic abundances that are produced by (n,y) reactions, for example " Cd(n, y) Cd. Many of these investigations were conducted by TIMS [137-139], but some cosmogenic Cd isotope variations of lunar rocks and soUs were evaluated based on MC-ICP-MS isotope ratio data that were originally acquired as part of a stable isotope study [134]. 

Figure 1.13 Selected analytical techniques used for metallomics studies. ICP-OES, inductively coupled plasma optical emission spectroscopy, ICP-MS, inductively coupled plasma mass spectrometry LA-ICP-MS, laser ablation ICP-MS XRF, X-ray fluorescence spectroscopy PIXE, proton induced X-ray emission NAA, neutron activation analysis SIMS, secondary ion mass spectroscopy GE, gel electrophoresis LC, liquid chromatography GC, gas chromatography MS, mass spectrometry, which includes MALDI-TOF-MS, matrix-assisted laser desorption/ ionization time of flight mass spectrometry and ESI-MS, electron spray ionization mass spectrometry NMR, nuclear magnetic resonance PX, protein crystallography XAS, X-ray absorption spectroscopy NS, neutron scattering.

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