A large number of current and future experiments in neutrino and dark matter detection use the scintillation light from noble elements as a mechanism for measuring energy deposition. The scintillation light from these elements is produced in the extreme ultraviolet (EUV) range, from 60-200 nm. Currently, the most practical technique for observing light at these wavelengths is to surround the scintillation volume with a thin film of Tetraphenyl Butadiene (TPB) to act as a fluor. The TPB film absorbs EUV photons and reemits visible photons, detectable with a variety of commercial photosensors. Here we present a measurement of the re-emission spectrum of TPB films when illuminated with 128, 160, 175, and 250 nm light. We also measure the fluorescence efficiency as a function of incident wavelength from 120 to 250 nm.

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Red light irradiation of 2-methyl-2-nitrosopropane (t-BuNO) in benzene in the presence of oxygen with a high OJt-BuNO ratio leads mainly to 2-methyl-2-nitropropane. In styrene part of the solvent is also attacked to give benzaldehyde and formaldehyde. Similar photolysis in P-pinene and cyclohexene gives oxidation on the allylic position, leading to mixtures of a-P unsaturated alcohols and ketones. Because no double bond shift takes place when p-pinene is oxidized, singlet oxygen is not involved.In all cases, the reactive species seems to be an adduct of oxygen and t-BuNO, which can add to double bonds (styrene) or abstract allylic hydrogens (P-pinene, cyclohexene).

Silver carbonate, precipitated on Celite, is a convenient reagent for the preparation in yields of 55-95% of C-nitroso compounds from hydroxylamines.

The similarity between the nitroso group and the carbonyl group in the reaction of phosphonate-carbanions with nitrosobenzenes has been demonstrated by several authors2-5. However, no such reactions with nitrosoalkanes have been described.In this communication we report reactions of diethyl phosphonatecarbanions with monomeric nitroso-alkanes. In contrast with the almost completely dimerized primary and secondary nitroso-alkanes, tertiary nitroso compounds exist to a large extent in the reactive monomeric form6.It may be expected therefore, that only tertiary nitroso-alkanes will react with phosphonate-carbanions. This is confirmed in the reaction of 2-methyl-2-nitrosopropane IIa (= tertiary-nitrosobutane) and of the acetoxy derivative IIb with triethyl phosphonoacetate (Ia) and with the methyl ester of (diethyl phosphon0)-p-methylcrotonate (Ib).In Table I some typical examples are listed, together with yields and spectroscopic characteristics of the resulting aldimines, which support the assigned structures.In all cases elementary composition and molecular weights as determined mass spectrometrically were -within experimental error -equal to calculated values.It is noteworthy that the applicability of our method is somewhat limited by the stability of the nitroso compound in the strongly basic reaction