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141.
The purpose of this paper is to investigate the compressible turbulent synthetic jet flow characteristics of a dual diaphragm
piezoelectric actuator. Experimentally, a flow visualization system was established to obtain the particle streak images scattered
from 10-μm red fluorescent spheres for observing the synthetic jet flowfield produced by a dual diaphragm piezo actuator.
The centerline velocity of the synthetic jet was also measured by using a hot-wire anemometry system. In the analysis, the
computational approach adopted the transient three-dimensional conservation equations of mass and momentum with the moving
boundary specified to represent the piezo diaphragm motion. The standard k-∈ two-equation turbulent model was employed for
turbulence closure. For the actuator operating at the frequency of 648 Hz, the particle streakline images in the cross-sectional
plane visualized a turbulent jet flow pattern in the far-field area. The hot-wire anemometry data indicated that the measured
centerline velocity of synthetic jets reached 3.8 m/s at y/d= 50. The predictions were compared with the visualized particle
streak images and centerline velocity of the synthetic jet in order to validate the computer code. The numerical simulation
revealed the time-periodic formation and advection of discrete vortex pairs. Caused by the outward movement of the piezo diaphragms,
air near the orifice was entrained into the actuator cavity when the vortex pairs were sufficiently distant from the orifice. 相似文献
142.
We present a method to deposit a wide range of radioactive probe atoms on surfaces, without introducing lattice damage or
contaminating the surface with other elements or isotopes. In this method, the probe atoms are mass-separated using an isotope
separator, decelerated to 5 eV, and directly deposited on the surface. The method allows for performing hyperfine interactions
experiments using trace amounts of radioactive probes located at surfaces and interfaces. The characteristics of the deposition
method will be described, with particular attention to the deceleration stage of the isotope separator. The method was tested
with perturbed angular correlation (PAC) experiments on the system In on Cu(17,1,1). The results are in agreement with molecular
dynamics simulations of the deposition process. New developments, in particular the study of the self-diffusion of Ag atoms
on Ag(100) by means of PAC with the 111Ag probe, are briefly discussed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
143.
A polymeric film of a biodegradable poly(p‐dioxanone) was grown from 490 nm silica particles by monolayer formation via self‐assembly of hydroxy‐terminated triethoxysilane and subsequent surface‐initiated ring‐opening polymerization of p‐dioxanone. The resulting silica/poly(p‐dioxanone) hybrid particles were characterized by means of 1H NMR spectroscopy, IR spectroscopy, thermogravimetric analysis, field‐emission scanning electron microscopy, and energy‐dispersive X‐ray spectroscopy.
144.
Hyun Jung Hong Kyong Hye Joung Yong Kyung Kim Min Jeong Choi Seul Gi Kang Jung Tae Kim Yea Eun Kang Joon Young Chang Joon Ho Moon Sangmi Jun Hyun-Joo Ro Yujeong Lee Hyeongseok Kim Jae-Hyung Park Baeki E. Kang Yunju Jo Heejung Choi Dongryeol Ryu Chul-Ho Lee Hail Kim Kyu-Sang Park Hyun Jin Kim Minho Shong 《Experimental & molecular medicine》2022,54(7):932
145.
146.
J.M.F. Labastida M. Roček E. Sánchez-Velasco Peter Wills 《Physics letters. [Part B]》1985,151(2):111-114
We construct the full N = 2 supergravity action in terms of N = 1 supergravity and matter fields. 相似文献
147.
We constructN=2 Yang-Mills theory in projective superspace by exploiting the analogy to Ward's twistor construction of self-dual Yang-Mills fields.Work supported in part by NSF grant No. PHY 85-07627 相似文献
148.
The P19 embryonal carcinoma cell line is a useful model cells for studies on cardiac differentiation. However, its low efficacy of differentiation hampers its usefulness. We investigated the effect of 5-azacytidine (5-aza) on P19 cells to differentiate into a high-efficacy cardiomyocytes. Embryoid-body-like structures were formed after 6 days with 1 mM of 5-aza in a P19 cell monolayer culture, beating cell clusters first observed on day 12, and, the production of beating cell clusters increased by 80.1% (29 of 36-wells) after 18 days. In comparison, the spontaneous beating cells was 33.3% (12 of 36-wells) for the untreated control cells. In response to 1 mM of 5-aza, P19 cells expressed bone morphogenetic protein-2 (BMP-2), BMP-4, Bmpr1a and Smad1 at day 6 or 9, and also cardiac markers such as GATA-4, Nkx2.5, cardiac troponin I, and desmin were up-regulated in a time-dependent manner after induction of BMP signaling molecules. Immunocytochemistry revealed the expression of smooth muscle a-actin, sarcomeric a-actinin, cardiac myosin heavy chain, cardiac troponin T and desmin, respectively. The proportion of sarcomeric a-actinin positive cells accounted for 6.48% on day 15 after 5-aza exposure as measured by flow cytometry. This study has demonstrated that 5-aza induces differentiation of P19 cells into cardiomyocytes in a confluent monolayer culture in the absence of prior embryoid formation and dimethyl sulfoxide exposure, depending in part on alteration of BMP signaling molecules. These results suggest that 5-aza treatment could be used as a new method for cardiac differentiation in P19 cells. 相似文献
149.
Zusammenfassung Es wird über Synthesen des 4,6-Dioxo-5,6-dihydro-4 Hpyrido[3,2,1-de]-carbazols I und 1,3-Dioxo-2,3-dihydro-1 Hpyrido[3,2,1-kl]-phenothiazins berichtet.Schweizer Priorität vom 9. 6. 1959. 相似文献
150.
Piperine from the fruits of Piper longum with inhibitory effect on monoamine oxidase and antidepressant-like activity 总被引:5,自引:0,他引:5
Lee SA Hong SS Han XH Hwang JS Oh GJ Lee KS Lee MK Hwang BY Ro JS 《Chemical & pharmaceutical bulletin》2005,53(7):832-835
A bioassay-guided isolation of the ethanol extract from the fruits of Piper longum yielded a known piperidine alkaloid, piperine, as a monoamine oxidase (MAO) inhibitor. Piperine showed an inhibitory effect against MAO-A (IC50 value: 20.9 microM) and MAO-B (IC50 value: 7.0 microM). Kinetic analyses by a Lineweaver-Burk plot clearly indicated that piperine competitively inhibited MAO-A and MAO-B with Ki values of 19.0+/-0.9 microM and 3.19+/-0.5 microM, respectively. The inhibition by piperine was found to be reversible by dialysis of the incubation mixture. In addition, the immobility times in the tail suspension test were significantly reduced by piperine, similar to that of the reference antidepressant fluoxetine, without accompanying changes in ambulation when assessed in an open-field. These results suggest that piperine possesses potent antidepressant-like properties that are mediated in part through the inhibition of MAO activity, and therefore represent a promising pharmacotherapeutic candidate as an antidepressant agent. 相似文献