Black powder, detection

For onsite analysis, the examination of the vast number of samples necessitates the use of quick, reliable, field portable equipment that can rapidly, quantitatively verify the many chemically different types of ammunition, explosives, and pyrotechnics. The most common suite of analytes to detect is large, consisting of very chemically different compounds and usually occurs at trace levels in complex environmental matrices. This suite encompasses smokeless powders, black powders, and numerous propellant and energetic formulations. Detection should also be sought for common decomposition products of these explosives such as the methylanalines, aminonitrotoluenes, nitrotoluenes, mono- and dinitoroglycerines, and the nitrobenzenes under on-site conditions. 

Detection of Faults in Black Powder Safety Fuses (Ref 14)... 

Powdered black copper oxide when stirred into water gives a black suspension and does not visibly dissolve. If the suspension is allowed to stand the black powder settles to the bottom and the clear liquid above contains so few ions of Cu++ and OH that they cannot be detected by the reagents commonly used for detecting these ions, NH4OH, Na2S. Yet we are confronted with the fact that, when acid is added to the suspension of copper oxide, the black powder dissolves completely and we obtain a clear blue solution of the cupric salt. The initial and final substances in this reaction are given in the equation... 

We ve all seen it on TV and in the movies... the detective arrives at the crime scene and stalks into the room wearing a trench coat. The area is taped off, and the experts from the crime lab are already dusting for fingerprints. In the movies, this usually means spreading black powder that will stick to the fingerprints, but in the real world, forensic scientists have developed new and better ways to make fingerprints visible and help identify the perp. ... 

The advantage of the MW-4 sequence in intensity is preserved at times T2e that allows to reduce considerably the detection time of the substances with the spin-lattice relaxation time Ti exceeding several seconds (TNT, PETN, HMX, black powder, etc.). 

Equation (39) is applicable for analysing the magnetisation behaviour of substances, for the detection of which the stationary state is practically not used, such as PETN, TNT and black powder. To analyse the magnetisation of substances with very short relaxation times, such as RDX, where quasi-stationary state is very short. Equations (60) and (61) can be used with satisfactory results. 

The Fido sensor is an extremely sensitive and selective detector for nitroaromatic explosives such as TNT. The sensor has also been shown to detect most smokeless powders and black powders. Work is now underway to develop polymers that enable detection of nitramine explosives, such as RDX and HMX. Recently, a new polymer was tested that shows promise for detection of the taggant dimethyldinitro butane (DMNB). Development of polymers for detection of peroxide-based explosives is also planned. 

Figure 7.17 contains the XRD pattern for the precursor molybdenum powder. Although the XRD pattern for the black powder in Figure 7.18 contained peaks for unreacted molybdenum that correspond to those in Figure 7.17, no unreacted nickel was detected. Molybdenum and nickel carbide peaks were both present. The XRD pattern of the light gray powder is shown in Figure 7.19. Although nickel and molybdenum carbides are again present, less unreacted molybdenum was present than in the black powder. The cause of reaction of molybdenum with the carbide powder in the presence of nickel is unclear. Recall that in the absence of nickel, molybdenum processed for 1 h reacted only minimally at the surface.

While IMS and MS are both widely used for explosives analysis, hybrid IM-MS instruments have recently been applied to detect explosives [186]. The lack of HLS-related research with IM-MS systems may be in part due to the availability of commercial IM-MS systems [183,187]. However, this hybrid technique offers a distinct advantage over both IMS and MS alone the ability to simultaneously separate samples by both mobility and mass. This twofold separation mechanism greatly decreases the likelihood of a mass or mobility interfer-ent masking the signal of the analyte of interest. In complex, real-world samples where matrix effects may significantly inhibit the detection of trace amounts of explosive material, the ability to separate in two dimensions (2D) is extremely powerful [188]. Figure 20.16 shows a typical 2D IM-MS plot of black powder with... 

Consequently, our test results showed that the APCI-MS system is suitable for detecting black powder in fireworks using the wiping test. Specifically, good sensitivity (500 ng for black powder) was obtained, and there were no false positives from everyday goods containing sulfur. 

Some years ago the inspector [bei mastare] Rinman described a method with which it is easy to detect the disposition for cold brittleness in iron. The method is founded on the fact that iron of that sort, after etching with hydrochloric acid, gives a black powder. 

The occurrence of the above redox reaction and hence the presence of tartrate is signalled by the fact that the silver oxide is dissolved on the addition of concentrated ammonium hydroxide whereas any elementary silver remains behind as a black powder. If very small amounts of tartaric acid are to be detected, it is advisable to conduct a comparison test on a blank. 

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