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Triplet (diphenoxyphosphory1)nitrene (3) was studied by solution phase laser flash photolysis, low-temperature absorption spectroscopy, and low-temperature EPR spectroscopy. In ethanol, an absorption maximum at 345 nm was observed upon laser flash photolysis of diphenyl phosphorazidate (1) and assigned to the triplet nitrene (z = 3.8 f 0.6 ps). After irradiation of 1 in an EPA glass at 77 K, an absorption attributed to the triplet nitrene was observed at 336 nm. The zero field splitting parameters from the EPR spectrum of the nitrene in EPA glass at 77 K were IDlhcl = 1.5408 cm-' and IElhcl = 0.007 39 cm-I. Stronger transient absorptions observed in hydroxylic solvents support the proposal that hydrogen bonding catalyzes intersystem crossing in nitrenes. [(a) Schuster, G. B.; Platz, M. S .

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Drop siae and velocity distributions were obtained for a pressure atomizer operating at 415 KF' a and a flowrate of 2.Zltf min. The nozzle produced a hollow-cone spray pattern with large drops travelling at high velocities confined to a relatively narrow conical sheet. These f a s t moving drops entrained air into the spray which served to convect the smaller drops t o the center of the spray cone. Measurements of the drop size and the axial and radial velocity components were obtained at radial and axial stations within the spray. The drop angles of trajectory for each size clws were calculated at representative stations. At the periphery, these results revealed that the large drops travelled at an angle of -30' corresponding t o the spray cone angle whereas the smallest drops moved at a mean angle of approximately +So with excursions to +IS0. With lower atomization pressures, a recirculation region at the center of the spray cone within a few centimeters from the exit of the nozzle was measured. Simultaneous measurements of the drop size and velocity revealed the axial velocity relaxation behavior for the various size classes. These results emphasize the need in the predictions of sprays to not only include the characteristics of the spray formation but also the dynamics of the spray drops and their interaction with the ambient turbulent flow. INTRODUCTIONDetailed mewurements of fuel spray drop size and velocity distributions remain LS an important contribution toward the understanding and improvement of spray combustion. Although numerous experimental investigations have been conducted, few, if any, have provided the complete data needed to facilitate development of advanced gas turbine combustors and to provide a sufficient base for testing and guiding the computational efforts. The required data must include simultaneous drop siae and velocity measurements at points near the plane of injection and at numerous downstream planes. Measurements of the gaseous mean velocity and turbulence intensity in the presence of the polydispersed phase are also required. Even in the case of simple pressure swirl atomizers, it is well-known that the spray formation is complicated by the entrainment and inflow of surrounding air, relaxation behavior of the various size classes, drop-drop interactions and

In English, auxiliaries form a cohesive category. Unlike main verbs, they raise to T. In Danish, it is not as obvious that auxiliaries form such a unified category. In root clauses, all verbal elements can raise to T (and then onto C), while in embedded clauses they always stay in situ. This makes telling where a given element sits in the extended verbal projection a challenging task. We examine a verbal element in Danish, gøre, that shows up when the verb phrase has been topicalized, elided, or pronominalized. Even though, from surface appearance, gøre might appear to be of category T or v, it is located, we argue, right in the middle. It is an auxiliary.But, unlike other auxiliaries, gøre is defective because it only subcategorizes for vPs that are pronominal. * Ange Strom-Weber made a substantial contribution to one of the earlier incarnations of this paper, presented at the 21st Comparative Germanic Syntax Workshop. We are also grateful to