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Aerodynamic instability in the transonic flow regime is one of the critical problems, during atmospheric reentry phase using sample return capsule (SRC), which can cause self-excited oscillation by aerodynamic force. In this study, we numerically investigated flow fields around a Hayabusa-type SRC to clarify the mechanism of aero dynamic instability using a computational fluid dynamics (CFD) approach. Flow fields at subsonic and supersonic speeds in a transonic wind tunnel were reproduced here. The computed results indicated that an expansion region of the flow field is important to make the SRC stable.

Electropherograms showing partial sequences of SOX10. Subject II:3 (a) has a homozygous G (indicated by an arrow) in the first nucleotide of codon 218, which encodes glycine (G). The proband (b) has a heterozygous G to T transition (arrow) at the same position that causes the glycine (G) at codon 218 to be replaced with a stop codon (*). This causes premature termination of protein synthesis. (DOCX 179 kb)

Summary of the eight candidate variants in the proband that were detected by whole exome sequencing. The SOX10 mutation was indicated in red. (DOCX 20 kb)

Hearing test results of the proband. OAE (a) and COR (b) audiometry revealed severe hearing loss. On the ABR test, neither the right (c) nor the left (d) ear responded to click sound stimulation at 105 dBnHL. Lt, left; Rt, right. (DOCX 295 kb)

Axial CT of the temporal bone. These axial CT images are the series of slices taken from the cranial side toward the caudal side (aâ h: left ear; iâ p: right ear). The CT imaging revealed hypoplasia of the semicircular canals and cochlea. (DOCX 1699 kb)

Pedigree of the family in this study. Round and square symbols indicate females and males, respectively. The individuals who were examined and whose blood samples were collected for DNA analysis are indicated by a horizontal bar above the symbol. None of the family members other than the proband had any Waardenburg syndrome-related symptoms. P: proband. (DOCX 43 kb)

A detailed chemical kinetic mechanism for hypergolic ignition of N2H4 in a N2O4-NO2 gas mixture has beenconstructed. In this mechanism, the hypergolic ignition is mainly caused by the sequential reactions of H atomabstraction from N2Hm by NO2: N2Hm+NO2=N2Hm-1+HONO/HNO2(m=4～1). Although the first step oftheHatom abstraction (m=4) is endothermic, consecutive abstraction reactions form=3, 2, and 1 are exothermic,and especially heat release by the reaction ofN2H+NO2=N2+HONO(m=1) is large because of N2 production.Temperature rise caused by the heat release accelerates the endothermic initiation reaction (m=4). This thermalfeedback is responsible for the hypergolic ignition at low temperatures. Because no experimental and theoreticalinformation is available on these reactions, rate coefficients were evaluated on the basis of transition state theory,unimolecular rate theory, and master equation analysis with quantum chemical calculations of potential energycurves. In addition, reactions of N2H4 with N2O4 isomers were also examined. The present kinetic mechanism canexplain gas-phase hypergolic ignition of N2H4/NTO mixtures at temperatures down to 200 K., 資料番号: PA1410010000