The Effect of the Inlet Total Pressure and the Number of Detonation Waves on Rotating Detonation Engines

AbstractThis paper presented a three-dimensional numerical study of rotating detonation engines, exploring the effect of the inlet total pressure and the number of detonation waves on the performance of rotating detonation engines. It was found that under the same total pressure of the inlet fuel, the number of detonation waves had little influence on the specific impulse, the thrust and the outlet flow of RDE. The number of detonation waves, however, affected the time needed to reach stable detonation.Besides, there was instability phenomenon in the development of detonation waves due to the relation between the number of detonation waves and the inlet total pressure. In order to speed up the process from ignition to stable detonation, the total pressure of the inlet fuel should match with the ignitions

Morphological Variation in Pachytriton labiatus and a Re-Assessment of the Taxonomic Status of P. granulosus (Amphibia: Urodela: Salamandridae)

Variation in relation to age and sex in a population of Pachytriton labiatus from Mt. Huangshan, Anhui Province, China was examined. There appeared to be distinct morphological variation among age/sex groups. We suggest that some of this variation is associated with ecology and behavior. Examination of the newt species from the type locality and nearby localities of Pachytriton granulosus (=Pingia granulosa), a taxonomically problematic species, revealed that this taxon was almost indistinguishable from juvenile P. labiatus. We therefore conclude that P. granulosus is a junior synonym of P. labiatus

J/ψ→ppˉϕJ/\psi \rightarrow p\bar{p}\phi decay in the isobar resonance model

Based on the effective Lagrangian approach, the $J/\psi \to p \bar{p} \phi$ decay is studied in an isobar resonance model with the assumption that the $\phi$-meson is produced from intermediate nucleon resonances. The contributions from the $N^*_{1/2^-}(1535)$, $N^*_{3/2^+}(1900)$, $N^*_{1/2^-}(2090)$ and $N^*_{1/2^+}(2100)$ states are considered. In terms of the coupling constants $g^{2}_{\phi N N^{*}}$ and $g^{2}_{\phi N N^{*}}$ extracted from the data of the partial decay widths of the $N^*$s to the $N\pi$ channel, the reaction cross section of the $\pi^{-}p\rightarrow n\phi$ process and the partial decay widths of the $J/\psi\rightarrow p\bar{p}\eta$ and $J/\psi\rightarrow p\bar{n}\pi^{-}$ processes, respectively, the invariant mass spectrum and the Dalitz plot for $J/\psi \to p \bar{p} \phi$ are predicted. It is shown that there are two types of results. In the type I case, a large peak structure around 2.09GeV implies that a considerable mount of $N\phi$ or $qqqs\bar s$ component may exist in the narrow-width $N^*_{1/2^-}(2090)$ state, but for the wide-width $N^*_{1/2^+}(2100)$ state, it has little $qqqs\bar s$ component. In the type II case, a small peak around 2.11GeV may only indicate the existence of a certain mount of $p\phi$ or $qqqs\bar s$ component in the narrow-width $N^*_{1/2^+}(2100)$ state, but no information for the wide-width $N^*_{1/2^-}(2090)$ state. Further BESIII data with high statistics would help us to distinguish the strange structures of these $N^*$s

Enhancement of Pneumocandin B0 Production in Glarea lozoyensis by Low-Temperature Adaptive Laboratory Evolution

The production of pneumocandin B0 is limited by feedback inhibition. Here, low-temperature adaptive laboratory evolution (ALE) was used to improve the production capacity of Glarea lozoyensis by enhancing its membrane permeability. After 50 cycles of ALE, the pneumocandin B0 production of the endpoint strain (ALE50) reached 2131 g/L, which was 32% higher than the starting strain (ALE0). ALE50 showed a changed fatty acid composition of the cell membrane, which-+h increased its permeability by 14%, which in turn increased the secretion ratio threefold. Furthermore, ALE50 showed increased intracellular proline and acetyl-CoA concentrations, superoxide dismutase (SOD), and catalase (CAT) activity, as well as total antioxidant capacity. The slight biomass decrease in ALE50 was accompanied by decreased isocitrate dehydrogenase (ICDH) and glucose-6-phosphate dehydrogenase (G6PDH) activity. Finally, a putative model of the accumulation and secretion of pneumocandin B0 in ALE50 was established. ALE is a promising method to release intracellular feedback inhibition