On the Design of Pulse Detonation Engines

This report addresses some basic issues in the structural and performance aspects of Pulse Detonation Engines (PDEs). Performance parameters studied include thrust-specific-fuel-consumption (TSFC), frequency limits, and thrust-to-weight ratio. A design surface is developed that accounts for various design limits. The structural aspects deal with critical parameters, material properties, and phenomena such as engine geometry, mass, yield stress, structural resonance due to flexural wave excitation, critical flaw size, and fracture toughness. Four materials for PDEs were chosen for comparison: silicon nitride, inconel, steel, and aluminum. Estimates of wall thickness and thrust-to-weight ratio are given over a range of operating conditions. Key issues and areas for further work are identified for both propulsion and performance aspects

Calculation of wing response to gusts and blast waves with vortex lift effect

A numerical study of the response of aircraft wings to atmospheric gusts and to nuclear explosions when flying at subsonic speeds is presented. The method is based upon unsteady quasi-vortex-lattice method, unsteady suction analogy, and Pade approximate. The calculated results, showing vortex lag effect, yield reasonable agreement with experimental data for incremental lift on wings in gust penetration and due to nuclear blast waves

Calculation of wing response to gusts and blast waves with vortex lift effect

A numerical study of the response of aircraft wings to atmospheric gusts and to nuclear explosions when flying at subsonic speeds is presented. The method is based upon unsteady quasi-vortex lattice method, unsteady suction analogy and Pade approximant. The calculated results, showing vortex lag effect, yield reasonable agreement with experimental data for incremental lift on wings in gust penetration and due to nuclear blast waves

New phagotrophic euglenoid species (new genus Decastava; Scytomonas saepesedens; Entosiphon oblongum), Hsp90 introns, and putative euglenoid Hsp90 pre-mRNA insertional editing

We describe three new phagotrophic euglenoid species by light microscopy and 18S rDNA and Hsp90 sequencing: Scytomonas saepesedens; Decastava edaphica; Entosiphon oblongum. We studied Scytomonas and Decastava ultrastructure. Scytomonas saepesedens feeds when sessile with actively beating cilium, and has five pellicular strips with flush joints and Calycimonas-like microtubule-supported cytopharynx. Decastava, sister to Keelungia forming new clade Decastavida on 18S rDNA trees, has 10 broad strips with cusp-like joints, not bifurcate ridges like Ploeotia and Serpenomonas (phylogenetically and cytologically distinct genera), and Serpenomonas-like feeding apparatus (8–9 unreinforced microtubule pairs loop from dorsal jaw support to cytostome). Hsp90 and 18S rDNA trees group Scytomonas with Petalomonas and show Entosiphon as the earliest euglenoid branch. Basal euglenoids have rigid longitudinal strips; derived clade Spirocuta has spiral often slideable strips. Decastava Hsp90 genes have introns. Decastava/Entosiphon Hsp90 frameshifts imply insertional RNA editing. Petalomonas is too heterogeneous in pellicle structure for one genus; we retain Scytomonas (sometimes lumped with it) and segregate four former Petalomonas as new genus Biundula with pellicle cross section showing 2–8 smooth undulations and typified by Biundula (=Petalomonas) sphagnophila comb. n. Our taxon-rich site-heterogeneous rDNA trees confirm that Heteronema is excessively heterogeneous; therefore we establish new genus Teloprocta for Heteronema scaphurum

Decays of the Meson BcB_c to a PP-Wave Charmonium State χc\chi_c or hch_c

The semileptonic decays, $B_{c}{\longrightarrow}{\chi_c}(h_c)+{\ell}+{{\nu}}_{\ell}$, and the two-body nonleptonic decays, $B_{c}{\longrightarrow}{\chi_c}(h_c)+h$, (here $\chi_c$ and $h_c$ denote $(c\bar c[^3P_J])$ and $(c\bar c[^1P_1])$ respectively, and $h$ indicates a meson) were computed. All of the form factors appearing in the relevant weak-current matrix elements with $B_c$ as its initial state and a $P$-wave charmonium state as its final state for the decays were precisely formulated in terms of two independent overlapping-integrations of the wave-functions of $B_c$ and the $P$-wave charmonium and with proper kinematics factors being `accompanied'. We found that the decays are quite sizable, so they may be accessible in Run-II at Tevatron and in the foreseen future at LHC, particularly, when BTeV and LHCB, the special detectors for B-physics, are borne in mind. In addition, we also pointed out that the decays $B_c\to h_c+...$ may potentially be used as a fresh window to look for the $h_c$ charmonium state, and the cascade decays, $B_c\to \chi_c[^3P_{1,2}]+l+\nu_l$ ($B_c\to \chi_c[^3P_{1,2}]+h$) with one of the radiative decays $\chi_c[^3P_{1,2}] \to J/\psi+\gamma$ being followed accordingly, may affect the observations of $B_c$ meson through the decays $B_{c}\to {J/\psi}+{l}+\nu_{l}$ ($B_c\to J/\psi+h$) substantially.Comment: 24 pages, 3 figures, the replacement for improving the presentation and adding reference