Grain spectroscopy

Infrared spectra of fats and oils are similar regardless of their composition. The principal absorption seen is the carbonyl stretching peak which is virtually identical for all triglyceride oils. The most common appHcation of infrared spectroscopy is the determination of trans fatty acids occurring in a partially hydrogenated fat (58,59). Absorption at 965 - 975 cm is unique to the trans functionaHty. Near infrared spectroscopy has been utilized for simultaneous quantitation of fat, protein, and moisture in grain samples (60). The technique has also been reported to be useful for instmmental determination of iodine value (61). 

The obvious application of microfocus Raman spectroscopy is the measurement of individual grains, inclusions, and grain boundary regions in polycrystalline materials. No special surface preparation is needed. Data can be obtained from fresh fracture surfeces, cut and polished surfaces, or natural surfeces. It is also possible to investigate growth zones and phase separated regions if these occur at a scale larger than the 1-2 pm optical focus limitation. 

X-ray difl raaion (structure grain size preferred orientation stress) Scanning laser microscopy Optical microscopy Oocnl thickness topography nucleation general morphology internal oxidation) l.R. spectroscopy (specialised analysis and applications)... 

Coarse-grained approaches, multiparticle collision dynamics, 90-92 Coarse velocity, linear thermodynamics, regression theorem, 18-20 Coherence spectroscopy, two-pathway excitation ... 

It was obtained by a pre-treatment of fresh impregnated HMOR in flowing air, up to 773 K. In these conditions, as detected by TEM, EDS and UV-visible spectroscopy (not shown, [12]), a fraction of Co2+ species, exchanged in the pores of HMOR, migrates on the outside of the zeolite grain, to form Co304 on the external surface of the HMOR grain. 

William Schopf studied supercrustal rock samples from Akilia Raman and ion microscopic photographs showed the presence of carbon-containing inclusions in grains of apatite. The carbon isotope ratio was determined by secondary ion mass spectroscopy (SIMS) the 813C value was -29% 4%, in agreement with earlier analyses. This in turn confirmed the values obtained by Mojzsis (1996), which had been questioned by Lepland et al. three years later. The final verdict on the oldest fossils in western Greenland may not be reached for several years yet (McKeegan et al., 2007 Eiler, 2007). 

Normally, time-resolved FT-IR spectroscopy (TRS FT-IR) possesses the same data characteristics. In a typical TRS FT-IR experiment, interferograms are assembled for a specific delay time after the photolysis pulse, and the data produced are normally finer-grained in frequency than in time. This type of experiment is complementary to experiments with fine-grained time information. It is particularly useful where a wide spectral range is necessary and works reasonably well for highly reproducible events which occur on relatively long timescales (fractions of seconds) (83). It is also an appealing system for use on shorter timescales, and it has... 

A typical ceramic sample contains contributions from the bulk, the grain boundaries, and the electrode. Each of these is characterized by a semicircular arc with a maximum at RCu> = 1, where the values of resistance, capacitance, and frequency refer directly to the bulk, grain boundaries, or electrodes (Fig. 6.7c). The separation of resistance due to the bulk from that of the grain boundaries is thus easily achieved using impedance spectroscopy. 

In agricultural applications, the most commonly analyzed constituents are water, protein, starch, sugars, and fiber [16-20]. Such physical or chemical functions such as hardness of wheat, minerals, and food values have no actual relation to chemicals seen in the NIR. These are usually done by inferential spectroscopy. That is, the effect of minerals or the relationship of the spectra to in vitro reactions is used in lieu of chemical analyses to NIR active constituents. Considering that all shipments of grain from the US since the 1980s have been cleared by NIR, it can be argued that this is a critical application of the technique. 

Petrovic and others (44) used X-ray photoelectron spectroscopy (XPS) to analyze the K, Al, and Si contents of experimentally altered K-feldspar grains, and found that alkali depletion, if it existed at all, could not extend to greater than 1.7 nm depth i.e., the "leached layer", if it exists at all, is less than 1.7 nm thick. Holdren and Berner (JH) using XPS observed a slight decrease in the Na/Si ratio of experimentally weathered alkali... 

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