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The generation of ammonium hydrogen sulfate from ammonium sulfate is of current interest because of its potential as a process component of bio-based organic acid production from biomass. An organic acid, for example succinic acid, is a chemical product that is used in food, cosmetics, deicing applications, etc. and a potential key carbon building block for numerous other materials. Its production from biomass (corn, etc.) makes it a renewable chemical resource, and the regeneration process described here minimizes the use of additional acid and base value reagents and byproduct (low value salt) waste. In the present work ammonium hydrogen sulfate (acid) and ammonia (base) were regenerated from ammonium sulfate using a thermal cracking method. Raman spectroscopy was used for primary analysis of the ammonium hydrogen sulfate product formed to determine the optimal reaction rate (80 °C/min) and to study the role of ammonium pyrosulfate in this reaction. [ABSTRACT FROM AUTHOR]

A series of polyhedral oligosilsesquioxane (POSS) nanosensors functionalized with fluorophores that change their wavelength of emission in response to their chemical environment has been synthesized and characterized by IR, NMR, UV, one- and two-dimensional fluorescence spectroscopy, MALDI-TOF MS, and electrospray MS. When each nanosensor in an array of nnanosensors is functionalized with a different wavelength shifting fluorophore, the array can generate a unique fingerprint comprised of nemission wavelength data points in response to a given chemical warfare agent (CWA) simulant or toxic industrial chemical (TIC). One-photon fluorescence fingerprints were constructed by measuring the fluorescence spectra of nanosensor−analyte pairs in solution. Two-photon fluorescence fingerprints were then generated by remotely interrogating nanosensor−analyte pairs using a femtosecond IR laser and a stand-off fluorimeter. Two-photon fingerprints were obtained for analytes in solution, on a surface, and in cloud form. A four-component nanosensor array could differentiate a homologous series of alcohols and distinguish G and VX classes of nerve agent simulants. [ABSTRACT FROM AUTHOR]