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The report describes the interaction of selected respiratory viruses and Eaton's agent. For example, enhancement of rhinovirus-RNA synthesis in Mycoplasma pneumoniae treated KB cells was demonstrated, and in contrast the inhibition of poliovirus-RNA synthesis in similar treated cell systems. In addition, basic studies concerning the action of rhinovirus on cell systems are explained in terms of nucleotide phosphorylation and RNA incorporation of 3H- uridine. Because of the importance of other selected respiratory viruses (adenovirus and influenza virus) on the military population these agents were investigated. In particular, the effect of mycoplasma on adenovirus 3H- thymidine uptake and influenza virus infections of mice. For comparison with adenovirus-mycoplasma systems another DNA virus, herpes simplex virus, was employed., Supported in part by Grant DAHC19-70-G-0009.

The objective of the study was to develop criteria for use in the design of aircraft gas turbine combustion chambers to minimize nitrogen oxide emissions. The approach adopted involved the development of a mathematical model of NOx emission from aircraft engine combustors; a parametric analysis, using the model, to determine the sensitivity of NOx emissions to variations of model parameters and engine design variables; evaluation of critical model parameters by means of experimental measurements; and the incorporation of the model into combustor design methods to provide guidelines for minimizing NOx emission while maintaining other performance and emission characteristics. The report describes the nitric oxide formation process and a computer program (NOXRAT) for calculating thermodynamic data. The program is based upon a six- reaction model of NO formation., See also Volume 1, AD741505 and Volume 3, AD741570. Sponsored in part by EPA.

The objective of the program was the development of analytical models of various flow configurations which can be used in the design of supersonic air-breathing propulsion systems. The work described in the report represents an extension of earlier studies in the program to conditions that exist in air-augmented rocket systems. These conditions vary according to the nature of the rocket propellant, as liquid propellants usually produce only gaseous fuel-rich combustion products whereas solid propellant rockets emit heterogeneous products which contain small combustible particles. The inclusion of particles produces significant effects upon reacting turbuelent flows, particularly when the particles themselves continue to burn. Some predictions of their behavior in a reacting flow field are presented. A series of systematic tests has been planned by which the experimental conditions proceed stepwise through conditions of increasing primary stream (rocket exhaust) complexity starting with a cold nonreactive gas and ending with a hot, reactive, heterogeneous mixture. The method permits the effects of temperature, of gaseous combustion and solid combustion upon a supersonic, reacting flow field to be isolated. Results obtained from the experimental tests are presented, and some conclusions are drawn from the data. (Author)

Because of the importance of adenovirus and M. pneumoniae infections in military personnel, emphasis was placed on a study of these interactions. These investigations have shown that M. pneumoniae apparently stimulates 3H-thymidine uptake (DNA synthesis) by adenovirus type 4 in L-132 cell monolayer systems, when cell systems were treated with mycoplasma at minus 48 and minus 24 hours prior to the virus inoculum. There appeared to be slight increases of adenovirus yields in mycoplasma-treated cells compared to virus-cell systems measured by both tube end-point and fluorescent antibody titrations. For the purpose of comparison, another DNA virus, Herpes simplex virus was selected. M. pneumoniae, added at 48 and 24 hours before herpes virus inoculations, appeared to enhance the viral-produced CPE in rabbit kidney monolayers. In contrast, if KB cell monolayers were pre-treated with herpes virus, instead of mycoplasma, and subsequently infected with rhinovirus, the rhinovirus RNA synthesis was partially or completely inhibited, respectively. In a comparable study, pre-treatment of KB cell systems with adenovirus type 4, did not appear to effect rhinovirus RNA synthesis. Finally, the interaction of M. pneumoniae and influenza A/PR8 virus was observed in 1,308 mice. These combinations of mycoplasma and influenza appeared to produce earlier symptoms and deaths than observed in mice infected with virus alone. (Author), See also Annual rept. no. 1, AD-699 425.

The objective of the study is to obtain data on turbulent, supersonic combustion which will facilitate development of ignition systems for use in scramjet engines under conditions when combustion cannot occur spontaneously. To this end a simple analytical model of a reacting, turbulent flow is presented, based upon the a priori assumption that combustion and turbulent mixing can be uncoupled. Predictions from this model are compared with some new experimental data on the ignition of ethylene in air. Both premixed and unpremixed situations are included. Tests of the validity of the mixing model are made for the nonreacting case by comparing predicted and measured velocity profiles in a duct; a satisfactory agreement is obtained. The predicted ignition requirements also match the measured values in most cases, with mixing- and reaction-rate data taken from the literature. Until uncertainties in these mixing- and reaction-rate expressions can be substantially reduced, the use of more subtle coupling models in the determination of ignition requirements does not appear to be justified. A much simpler model is also presented and used to derive a useful criterion for the prediction of the ignition boundaries in premixed fuel-air flows. (Author)

Studies were performed to determine the effect of Mycoplasma pneumoniae on rhinovirus replication in KB cells. Rhinovirus-RNA synthesis in KB cell monolayers was measured by tritiated-uridine uptake in the presence of actinomycin D. It was observed that viral-RNA synthesis in M. pneumoniae pre-inoculated cells was stimulated throughout the entire period of synthesis, whereas triated-uridine uptake by rhinovirus in non-mycoplasma treated cultures ranged from < 0.1% to 80% of the uptake in the mycoplasma-virus inoculated cultures at 7 to 9 hours post-infection. In these studies, M. pneumonia was grown on glass to eliminate the PPLO medium. However. if PPLO medium was added to the mycoplasma inoculum, stimulation of viral RNA synthesis was greater than in the presence of mycoplasma alone. Influenza virus, A/PR8, grown in Rhesus monkey kidney monolayers inoculated with M. pneumoniae, showed a two fold stimulation of HA titers greater than virus grown in RMK cells without mycoplasma. In preparation for adenovirus-mycoplasma studies, DNA synthesis of mycoplasma in human gingival and HeLa cell culture was studied. M. salivarium uptake of thymidine-3H was approximately 4 fold greater than that of M. pneumoniae in both cell systems. (Author)

The objective of the study was to develop criteria for use in the design of aircraft gas turbine combustion chambers to minimize nitrogen oxide emissions. The approach adopted involved the development of a mathematical model of NOx emission from aircraft engine combustors; a parametric analysis, using the model, to determine the sensitivity of NOx emissions to variations of model parameters and engine design variables; evaluation of critical model parameters by means of experimental measurements; and the incorporation of the model into combustor design methods to provide guidelines for minimizing NOx emission while maintaining other performance and emission characteristics. The results of the study and the NOx emission control criteria are described., See also Volume 2, AD741506. Sponsored in part by EPA.

The objective of the study was to develop criteria for use in the design of aircraft gas turbine combustion chambers to minimize nitrogen oxide emissions. The approach adopted involved the development of a mathematical model of NOx emission from aircraft engine combustors; a parametric analysis, using the model, to determine the sensitivity of NOx emissions to variations of model parameters and engine design variables; evaluation of critical model parameters by means of experimental measurements; and the incorporation of the model into combustor design methods to provide guidelines for minimizing NOx emission while maintaining other performance and emission characteristics. The report describes combustion and flow processes in gas turbine combustors and a computer program (GASNOX) for calculating gas properties and NO concentrations throughout a combustor. This program is based upon a three-zone, heterogeneous model of gas turbine combustor operation. Program GASNOX is used with input data from Program NOXRAT to calculate NO emission rates., See also Volume 2, AD741506.