Abstract: Novel compounds are provided in the form of a salt having the structure of formula (I) or formula (II) wherein: R1 is selected from the group consisting of H, C1-C24 alkyl, C2-C24 alkenyl, C2-C24 alkynyl, C5-C20 aryl, C6-C24 alkaryl, and C6-C24 aralkyl; R2 is H, C1-C24 alkyl or nitro; X is O or NR3 in which R3 is H, C1-C24 alkyl or nitro; Zm+ is a monovalent cation, a divalent cation, or a trivalent cation; M+ is an alkali metal cation; and m and n are 1, 2 or 3, with the proviso that the compound contains at least one nitro group. Exemplary such compounds are the ammonium salt of the N-hydroxyl-N?-nitrourea (NHNU) monoanion and the disodium salt of the NHNU dianion. Also provided, as novel compositions of matter, are N-hydroxyl-N?-nitrourea and N-hydroxyl-N-nitroguanidine in electronically neutral form. The compounds are useful in a variety of contexts, but are primarily useful as high energy oxidizing agents in explosive compositions, propellant formulations, gas-generating compositions, and the like.

Abstract: Silazanes and related compounds are prepared by (a) providing a precursor containing at least one Si--N bond, cleaving an Si--N bond in the precursor in the presence of hydrogen or a hydrogen donor, and reacting the cleavage product with a second cleavage product or with a compound containing an Si--H bond, an N--H bond, or both, to produce an initial silazane product having at least one newly formed Si--N bond or (b) providing one or more reactants which contain an Si--H bond and an N--H bond, and causing reaction to occur between the two bonds in the presence of a transition metal catalyst to form an initial silazane product having newly formed Si--N bonds. Further products may result from additional reaction of either type. Novel compounds, including siloxazanes and high molecular weight polysilazanes, are provided. The compounds may be pyrolyzed to yield ceramic materials such as silicon nitride, silicon carbide and silicon oxynitride.

Abstract: A simulated human ocular system for practicing the surgical techniques required for the removal of cataractous lenses utilizing posterior chamber lens emulsification and, optionally, the techniques required from small incision implantation and refractive surgery is provided. A human eye is generally imitated by an outer orb having three inner, connected chambers separated by membranes that correspond to the cornea, the iris, and the posterior chamber membrane. A lens phantom is releasably attached to the orb within the chamber located between the iris and the posterior chamber membrane. The lens phantom consists of a structured, water-sensitive composition, such as a cross-linked gelatin to which a water soluble polymer has been added, and is thereafter encapsulated within a transparent vinyl or vinylidene chloride copolymer film.

Abstract: A simulated human ocular system for practicing the surgical techniques required for the removal of cataractous lenses utilizing posterior chamber lens emulsification and, optionally, with the techniques required for small incision implantation is provided. A human eye is generally imitated by an outer orb having three inner, connected chambers separated by membranes that correspond to the corner, the iris, and the posterior chamber membrane. A lens phantom is releasably attached to the orb within the chamber located between the iris and the posterior chamber membrane. The lens phantom consists of a structured, water-sensitive composition, such as a cross-linked gelatin to which a water soluble polymer has been added, and is thereafter encapsulated within a transparent vinyl or vinylidene chloride copolymer film.