The thermal behaviour of two different Al nanopowders and a micron‐sized Al powder was studied using DSC, simultaneous TG‐DTA, and accelerating rate calorimetry (ARC). The results show that the reactivity of Al powder increases as the particle size decreases. The thermal stability of the smaller Al nanopowder (Als) in water and in a humid atmosphere was determined using ARC and TG‐DTA, respectively. Atomic Absorption Spectrometry (AAS), X‐Ray Photoelectron Spectrometry (XPS) and Auger Electron Spectrometry (AES) were used to characterize the surface chemistry of Alex. The outgassing behaviour for mixtures of RDX and the various Al powders was investigated using TG‐DTA‐FTIR‐MS. Evolution of NO2 and N2O from a chemical interaction between Al nanopowders and RDX was observed. The effect of Als and Alex on the thermal stability of TNT, RDX, Comp B, and AP was determined using ARC. Addition of Als significantly lowered the onset temperature for TNT and RDX decomposition. Electrostatic discharge (ESD) sensitivities of Al nanopowders and their mixtures with TNT, Comp B, RDX and AP were determined. The results show that the AP/Als mixture is very sensitive to ESD. Standard dust explosibility tests demonstrated that Alex is highly explosible.

This paper describes a simple method for the analysis of tocopherols in tissues by which frozen tissues-70 degrees C were pulverized at dry ice temperatures (-70 degrees C) and immediately extracted with hexane. There was no need to remove the coeluting lipids from tissues by saponification, since at that level of neutral lipids in the sample, there was no reduction in fluorescence response. For the analysis of oil, in which large amounts of neutral lipids were coextracted, a 20% reduction of fluorescence response was observed, but the response was equal for all tocopherol forms, and was appropriately corrected. Saponification was used only when tocopherol esters were present, and only after an initial hexane extraction to remove the free tocopherols in order to avoid their loss by saponification, particularly non alpha-tocopherol and tocotrienols. All the tocopherols and tocotrienols were separated on a normal-phase diol (epoxide) column that gave consistent and reproducible results, without the disadvantages of nonreproducibility with silica columns, or the lack of separation with reversed-phase columns. The tocopherols were quantitated by using a tocopherol form not present in the sample as an internal tocopherol standard, or using an external tocopherol standard if all forms were present, or when the sample was saponified. Piglet heart and liver samples showed the presence of mainly alpha-tocopherol, with minor amounts of beta- and gamma-tocopherol and alpha-tocotrienol, but no delta-tocopherol. Only small amounts of tocopherol esters were present in the liver but not in the heart.

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A novel three-directional thin layer chromatography (TLC) method is reported by which all the polar and neutral lipids are isolated on a single TLC plate. Following resolution of the phospholipids by two-directional TIC, lipids are visualized by ultraviolet light after spraying with 2',7'-dichlorofluorescein. A line is drawn across the plate, parallel to the second direction of development, separating the resolved phospholipids and the neutral lipids concentrated along the solvent front. The TLC plate is then chromatographed in the reverse direction of the second development to resolve the neutral lipids. By exposing the iipids to HCI fumes after the first development, the plasmalogen content of the lipids may also be determined. This new technique is rapid and lends itself to qualitative and quantitative analyses of total lipids.

The thermal behaviour in air of two Al nanopowders, Alss and Alsstef, a Teflon coated version of Alss, was determined using DSC, TG-DTA and accelerating rate calorimetry (ARC). Compared to two larger Al nanopowders, for which hazards results have been reported, Alss and Alsstef are less reactive in air, possibly due to the nature of the passivating and coating layers. The stability of Alss and Alsstef in a wet environment was also investigated using ARC. Alss is very reactive with water, which could lead to a problem of aging in a humid atmosphere. The ∫coating∫ of Alsstef significantly reduces the reactivity of Alss with water. Outgassing behaviour of mixtures of ADN, GAP and various Al powders was investigated using TG-DTA-FTIR-MS. No chemical interactions were observed between ADN/Al, GAP/ Al and ADN/GAP. The effect of the addition of Al nanopowders on the thermal decomposition of ADN and GAP was studied using ARC. Al nanopowders had a minor effect on the thermal stability of ADN, while the addition of Alss and Alsstef lowered the onset temperature of GAP. The electrostatic discharge (ESD), impact and friction sensitivities of Al nanopowders and their mixtures with ADN and GAP were also determined. Al nanopowders appear to sensitize ADN to ESD, impact and friction.