Identification tests microscopic observation

D. Place a few drops of the stirred mixture from Identification Test A on a microscope slide, and insert a coverglass. Observe at 100 magnifications with a microscope. Fibers and fiber fragments are visible, regardless of the degree of fineness of the sample. 

Cyclic nitramines such as RDX or cyclotetra-methylenetetranitramine (HMX) are widely used in military composites such as Composition B (TNT and RDX) and Composition C-4 (US) or PE-4 (British) and in commercial blasting explosives such as Semtex (a Czech-made mining explosive). HMX is present as a by-product in RDX made by the Bach-mann process and has applications in explosives to be used in high-temperature environments. Chemical tests for RDX include the J-Acid and thymol tests. A number of TLC systems for RDX and HMX have been reported. With adequate sample, IR identification of the pure material in a micro-potassium bromide pellet is simple. If a diamond anvil sample holder or microscope attachment is available, excellent spectra of pure samples of milligram size or even of single crystals are easily obtained. When HMX is observed in RDX-based explosives, its concentration may suggest the national origin of the explosive. 

Identification to the species level may be completed if the sample is large enough to permit observation of other morphological identifiers. Wood that has been treated for industrial uses, such as paper, can be identified as such microscopically. Further microchemical tests can be applied to paper-making fibers to establish the end-use of the paper (i.e., newsprint versus stationery). 

Shi et al. studied the inhibition of AA2024-T3 corrosion in O.OSMNaCl solution by cerirrm cinnamate. The test solutions were produced by dissolving supersaturated cerirrm cinnamate into O.OSMNaCl solution. The couports were abraded, washed, rirrsed and immersed in the aerated test solutiorts for different periods at 20 °C. SEM observations of the morphologies of coupons were carried out after 2 days immersion in test solutions with and without the presence of cerium cinnamate. The inhibitor film was also observed by an atomic force microscope (AFM). XPS was used for the identification of different elements present on corrosion coupon surfaces. 

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