We have developed a simple, reversed-phase high-performance liquid chromatography (RP-HPLC) method for the determination of bisphenol A (BPA) in thermal paper cash register receipts (CRs). The method is suitable for analysis of other types of bisphenols and it involves an overnight extraction of CRs with acetonitrile (AN) at 50 °C followed by the HPLC analysis on a Supelcosil LC18 column (150 × 4.6 mm, particle size: 5 μ) using 50% AN in water as the mobile phase (5 min, isocratic). The composition of AN in the mobile phase changed to 100% over a 10 min period (linear gradient) and then held at 100% AN for 10 min (isocratic). The flow rate was set at 1 mL/min (injection volume: 20 μL) and the eluent was monitored at 234 nm. The authentic BPA eluted with a retention time of 5.9 min and gave a linear detector response in the concentration range of 0.23-50 mg/L. BPA in the CR extracts also eluted with the same retention and had identical absorbance properties as the standard. When CR extracts were co-injected with authentic BPA, they were resolved as a single peak. Further, GC/MS/EI analysis of authentic BPA and the HPLC-purified CR extracts have identical ion chromatograms and fragmentation of the molecular ion (m/z = 228). We have analyzed 170 CRs collected from 62 different vendors including supermarkets, fast food restaurants, gas stations and banking outlets. Almost all cash receipts (n = 168) showed the presence of BPA in the concentration range of 0.45-4.26% (M ± SD, 1.54 ± 0.73%).

Traditionally, thermal barrier coatings (TBCs) are used in gas turbine engines to create an insulation layer between the metallic components and the gases in the hot section. Atmospheric plasma spray (APS) is a common method used to produce TBCs. The goal of this study is to study the porosity and thermal cycling behavior of standard (STD) and vertically cracked (VC) thermal barrier coatings (TBCs) fabricated by Atmospheric Plasma Spray (APS) for two different thicknesses, 300 and 600 μm respectively. Electron Beam Physical Vapor Deposition (EBPVD) coatings with 300 micron thickness prepared under tumbled and non-tumbled conditions were studied. For this study, mercury porosimeter equipment (POREMASTER 33) by Quantachrome Instruments was used to measure porosity, and pore size distribution. Scanning Electron Microscopy (SEM) images were obtained for all the samples. The images showed clear microstructural difference between the APS and EBPVD coatings. All the coatings were thermal cycled to 1200°C and the conventional APS-STD (300μm) performed the best followed by APS-VC coatings and EBPVD coatings which performed similarly.

Thermal barrier coatings (TBCs) that can be suitable for use in industrial gas turbine engines have been processed and compared with electron beam physical vapor deposition (EBPVD) microstructures for applications in advanced gas turbines that use coal-derived synthesis gas. Thermo-physical properties have been evaluated of the processed air plasma sprayed TBCs with standard APS-STD and vertically cracked APS-VC coatings samples up to 1300 o C. Porosity of these selected coatings with related microstructural effects have been analyzed in this study. Wet and dry thermal cycling studies at 1125 o C and spalling resistance thermal cycling studies to 1200 o C have also been carried out. Type I and Type II hot corrosion tests were carried out to investigate the effects of microstructure variations and additions of alumina in YSZ top coats in multi-layered TBC structures. The thermal modeling of turbine blade has also been carried out that gives the capability to predict in-service performance temperature gradients. In addition to isothermal high temperature oxidation kinetics analysis in YSZ thermal barrier coatings of NiCoCrAlY bond coats with 0.25% Hf. This can affect the failure behavior depending on the control of the thermally grown oxide (TGO) growth at the interface. The TGO growth kinetics is seen to be parabolic and the activation energies correspond to interfacial growth kinetics that is controlled by the diffusion of O 2 in Al 2 O 3 . The difference between oxidation behavior of the VC and STD structures are attributed to the effects of microstructure morphology and porosity on oxygen ingression into the zirconia and TGO layers. The isothermal oxidation resistance of the STD and VC microstructures is similar at temperatures up to 1200 o C. However, the generally thicker TGO layer thicknesses and the slightly faster oxidation rates in the VC microstructures are attributed to the increased ingression of oxygen through the grain boundaries of the vertically cracked microstructures. The plasma sprayed TBC microstructure (VC and STD) with NiCoCrAlY-Hf bond coat are stable up to 1100 o C. However, as with other TBC structures, a considerable amount of interdiffusion was observed in the different layers, although the TBC growth was self-limiting and parabolic. The addition of Hf to the VC microstructure appears to have some potential for the future development of robust TBCs with improved isothermal and service temperatures in advanced gas turbines.

In the title compound, C10H11N3O6, the torsion angles about the bonds to the benzene ring are less than 4°, except for the nitro groups, which are twisted out of the ring plane by 25.27 (3) and 43.63 (2)°. The N—H group forms a bifurcated hydrogen bond, with an intramolecular component to a nitro group O atom and an intermolecular component to the other nitro group, thereby forming chains propagating in the [010] direction. Several weak C—H...O interactions are also present.

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The title compound, C9H10N2O4, crystallizes with a disordered nitro group in twinned crystals. Both the methoxy group and the acetamide groups are nearly coplanar with the phenyl ring, and the C—N—C—O torsion angle [0.2 (4)°] is also insignificantly different from zero. Overall, the 12-atom methoxyphenylacetamide group is nearly planar, with an r.m.s. deviation of 0.042 Å. The nitro group is twisted out of this plane by about 30°, disordered into two orientations with opposite senses of twist. In the crystal, the N—H group donates a hydrogen bond to a nitro oxygen atom, generating chains propagating in the [101] direction. The amide carbonyl oxygen atom is not involved in the hydrogen bonding.