1,846 research outputs found
Anodized aluminium pressure sensitive paint: effect of paint application technique
The porous surface of the Anodized Aluminium Pressure Sensitive Paint (AA-PSP) is what differentiates it from conventional sol–gel based PSPs, leading to a faster response time of the paint. The objective of the current study is to examine the effect of the paint application technique, i.e., whether the AA substrate is dipped or sprayed, on the pressure and temperature sensitivity. A more practical procedure for preparing the AA samples is also presented. Scanning Electron Microscope (SEM) images are acquired together with the calibration of the AA-PSP at various temperatures and pressures to determine the effectiveness of each application technique. The results revealed that the AA sample which was dipped in the PSP solution shows a higher pressure sensitivity than the sprayed one. The SEMs show that spraying leads to the covering up of the micropores created on the surface and undermining the benefit of anodization
EVALUATION OF EXHAUST GAS FROM BIO-DIESEL FUEL ENGINE
Joint Research on Environmental Science and Technology for the Eart
Effect of Impurities in Description of Surface Nanobubbles
Surface nanobubbles emerging at solid-liquid interfaces of submerged
hydrophobic surfaces show extreme stability and very small (gas-side) contact
angles. In a recent study Ducker (W. A. Ducker, Langmuir 25, 8907 (2009).)
conjectured that these effects may arise from the presence of impurities at the
air-water interface of the nanobubbles. In this paper we present a quantitative
analysis of this hypothesis by estimating the dependence of the contact angle
and the Laplace pressure on the fraction of impurity coverage at the liquid-gas
interface. We first develop a general analytical framework to estimate the
effect of impurities (ionic or non-ionic) in lowering the surface tension of a
given air-water interface. We then employ this model to show that the
(gas-side) contact angle and the Laplace pressure across the nanobubbles indeed
decrease considerably with an increase in the fractional coverage of the
impurities, though still not sufficiently small to account for the observed
surface nanobubble stability. The proposed model also suggests the dependencies
of the Laplace pressure and the contact angle on the type of impurity
Ground-state electric quadrupole moment of 31Al
Ground-state electric quadrupole moment of 31Al (I =5/2+, T_1/2 = 644(25) ms)
has been measured by means of the beta-NMR spectroscopy using a spin-polarized
31Al beam produced in the projectile fragmentation reaction. The obtained Q
moment, |Q_exp(31Al)| = 112(32)emb, are in agreement with conventional shell
model calculations within the sd valence space. Previous result on the magnetic
moment also supports the validity of the sd model in this isotope, and thus it
is concluded that 31Al is located outside of the island of inversion.Comment: 5 page
Highly c-axis-oriented AlN film using MOCVD for 5GHz-band FBAR filter
科研費報告書収録論文(課題番号:14205053/研究代表者:坪内和夫/ソフトウェア無線端末用超低消費電力GHz帯RF DSPの開発
Application of AA-PSP to hypersonic flows: the double ramp model
Anodized Aluminium Pressure Sensitive Paint (AA-PSP) is known for its rapid response characteristics, making it a highly desirable technique when studying high-speed phenomenon on a global scale. The current study examines the efficacy of the AA-PSP technique, which is prepared with a more practical approach than that reported in literature, in analysing the flow characteristics of a double ramp model placed in hypersonic flow of M = 5. Three different flow angles of 0°, −2°, and −4° are studied. Two-dimensional colour schlieren visualisation, using a colour wheel, is employed alongside high sensitivity Kulite pressure tap data to corroborate the AA-PSP findings. The AA-PSP results show good correlation between the qualitative schlieren and ±8.9% discrepency with the quantitative pressure tap data. The more practical AA-PSP preparation proposed in the current study, which uses aluminium alloy 6-series rather than pure aluminium, is proved to have the response time and the accuracy to be applied to unsteady high-speed flows
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