Noise generation from interacting high speed axisymmetric jet flows Semiannual status report, 1 Jun. 1968 - 31 Dec. 1969

Far field noise generation from interacting coaxial jet flows, and nozzle operational mode

Human-Centred Design for Intelligent Environments: Preface to the proceedings of the workshop on Human Centred Design for Intelligent Environments.

Preface to the proceedings of the workshop on “Human Centred Design for Intelligent Environments” organised in conjunction with the 2016 BCS British HCI Conference held at Bournemouth University, July 11th-15th 2016

9-(5-Bromo-2-hy­droxy­phen­yl)-10-(2-hy­droxy­prop­yl)-3,3,6,6-tetra­methyl-1,2,3,4,5,6,7,8,9,10-deca­hydro­acridine-1,8-dione

The dihydro­pyridine ring in the title compound, C26H32BrNO4, adopts an envelope conformation with the methine C atom representing the flap. The cyclo­hexenone rings also adopt envelope conformations. The phenolic hy­droxy group forms an intra­molecular hydrogen bond to one of the two keto O atoms. Inter­molecular weak C—H⋯O hydrogen bonding is present in the crystal structure. The hy­droxy­propyl group is disordered over two sets of sites with an occupancy ratio of 0.636 (6):0.364 (6)

2,2′-[(E,E)-cis-(Cyclo­hexane-1,4-di­yl)bis­(nitrilo­methanylyl­idene)]diphenol

In the title compound, C20H22N2O2, the asymmetric unit contains two independent half-mol­ecules, which are both completed by crystallographic inversion symmetry. The cyclo­hexane rings of both mol­ecules adopt chair conformations; the N atoms are in equatorial orientations in one mol­ecule and in axial orientations in the other. Both mol­ecules feature two intra­molecular O—H⋯N hydrogen bonds, which generate S(6) rings

Study of root para-nodules formation in wheat (Triticum durum) inoculated with Frankia strain CcI3 and treated with 2, 4-dichlorophenoxyacetate (2, 4-D)

Frankia strains can induce N2-fixing root nodules on certain non-leguminous plants. It is known that exogenous application of 2,4-dichlorophenoxyacetate (2,4-D) affects root morphology. In this work, wheat roots were treated with 2,4-D and inoculated with the actinomycete Frankia. Wheat plants grew in a growth chamber with hydroponic medium. Binocular observation revealed that para-nodules were formed when wheat roots were inoculated with Frankia and the root length was enhanced. When the inoculation with Frankia was combined to 2,4-D treatment, the para-nodules formed were bigger and more numerous, while the root length was shortened.Keywords: Frankia, wheat, roots, para-nodules, 2,4-dichlorophenoxyacetateAfrican Journal of Biotechnology Vol. 12(35), pp. 5427-543

2-Anilino-3-(2-hy­droxy­prop­yl)-4-methyl-1,3-thia­zol-3-ium chloride

In the title compound, C13H17N2OS+·Cl−, the thia­zolium ring mean plane makes a dihedral angle of 55.46 (9)° with the benzene ring. In the propanol group, the N—C—C—C and N—C—C—O torsion angles are 172.58 (15) and 52.9 (2)°, respectively, and the S—C—C—C torsion angle is 178.99 (18)°. In the crystal, mol­ecules are linked by O—H⋯Cl and N—H⋯Cl hydrogen bonds, forming zigzag chains along [001]. There is also a C—H⋯Cl inter­action present

Combustion contribution to noise in jet engines

The relative importance of combustion as a source of noise in a flow regime representative of a subsonic jet engine exhaust was investigated. The combustion noise source characteristics were obtained from pressure and temperature fluctuation measurements in the combustor and exhaust nozzle. The similarity between the fluctuations in this source region and the far field noise were compared. In the jet exhaust velocity range between 450 and 660 ft/sec investigated in detail, the frequencies of dominant pressure and temperature fluctuations in the combustor were also the frequencies of the dominant far field noise. The overall noise levels were 14 to 20 dB higher than from a corresponding clean jet in the same velocity range. Thus it seemed clear that the unsteadiness associated with the combustion process was responsible for the dominant noise in the far field. A simple analysis to predict the far field noise due to the internal pressure fluctuations causing exit plane velocity fluctuations produced trends closely resembling the measured results, but under predicted the far field noise over the spectral range examined. The possible reason for the higher far field noise is direct transmission of acoustic waves through the nozzle, which was not accounted for in the prediction scheme

One-sided Cauchy-Stieltjes Kernel Families

This paper continues the study of a kernel family which uses the Cauchy-Stieltjes kernel in place of the celebrated exponential kernel of the exponential families theory. We extend the theory to cover generating measures with support that is unbounded on one side. We illustrate the need for such an extension by showing that cubic pseudo-variance functions correspond to free-infinitely divisible laws without the first moment. We also determine the domain of means, advancing the understanding of Cauchy-Stieltjes kernel families also for compactly supported generating measures

4a-Hy­droxy-3,3,6,6-tetra­methyl-9-[6-(3,3,6,6-tetra­methyl-1,8-dioxo-2,3,4,5,6,7,8,9-octa­hydro-1H-xanthen-9-yl)pyridin-2-yl]-2,3,4,4a,5,6,7,8,9,9a-deca­hydro-1H-xanthene-1,8-dione ethanol hemisolvate hemihydrate

The pyridine ring in the title compound, C39H47NO7·0.5C2H5OH·0.5 H2O, is connected to one 3,3,6,6-tetra­methyl-1,8-dioxoxanthenyl and one 4a-hy­droxy-3,3,6,6-tetra­methyl-1,8-dioxodeca­hydroxanthenyl substituent in the 2- and 6-positions of the ring. In the former substituent, the six-membered xanthenyl ring adopts a flattened envelope conformation (with the methine C atom as the flap) while in the latter, the six-membered xanthenyl ring adopts a twisted envelope conformation (with the C atom bearing the hy­droxy group representing the flap). The hy­droxy H atom forms an intra­molecular hydrogen bond to the pyridyl N atom. An ethanol solvent mol­ecule is disordered with respect to a water mol­ecule in a 1:1 ratio. The water mol­ecule itself is disordered over two positions of equal occupancy

10-(2-Hy­droxy­eth­yl)-9-(2-hy­droxy­phen­yl)-3,3,6,6-tetra­methyl-1,2,3,4,5,6,7,8,9,10-deca­hydro­acridine-1,8-dione

The dihydro­pyridine ring in the title compound, C25H31NO4, adopts an envelope conformation with the methine C atom representing the flap. The cyclo­hexenone rings also adopt envelope conformations with the C atoms bearing the methyl C atoms representing the flaps. The phenolic hy­droxy group forms an intra­molecular hydrogen bond to one of the two keto O atoms. The hy­droxy group of the N-bonded alkyl chain forms an inter­molecular hydrogen bond to the other keto O atom of an adjacent mol­ecule. The latter hydrogen bond leads to the formation of a helical chain running along the b axis