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Experimental investigation of transonic buffet was conducted in JAXA 2m×2m transonic wind tunnel in order to obtain the validation data for unsteady computational fluid dynamics and to clarify the buffet phenomena of an 80% scaled NASA common research model. Unsteady pressure distributions on the two lines of the main wing were successfully measured on the transonic buffet condition. Mach number of the uniform flow was 0.85. Reynolds numbers based on the reference chord length were 1.515×10 6 and 0.947×10 6 . The shockwave oscillation on the wing can be classified into three regions, a small oscillation region without separation, an oscillation region with bump in the power spectrum, and a large oscillation region with broadband power spectrum. The Strouhal number based on the bump peak frequency was about 0.3. The cross-correlation and the phase analysis revealed that the pressure fluctuation of the bump frequency propagated from the wing root side to the wing tip side. Nomenclature b = span of the model f = frequnecy C p = pressure coefficient on the main wing C prms = root mean square of pressure coefficient fluctuation C p95% = pressure coefficient at 95% of local chord of the main wing c = local chord length   Mach number P 0 = total pressure of uniform flow PSD = power spectrum density Re = Reynolds number RMS = root mean square St = Strouhal number, Stfc/U U = velocity of uniform flow U c = propagation velocity of the pressure fluctuation x = coordinate in chord direction at each span location y = coordinate in span direction   angle of attack   phase of cross-spectrum analysis   dimensionless coordinate in span direction, y/(b/2)

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Abstract:Most methods reported for cell-surface patterning are generally based on photolithography and use of silicon or glass substrates with processing analogous to semiconductor manufacturing. Herein, we report a novel method to prepare patterned plastic surfaces to achieve cell arrays by combining homogeneous polymer grafting by electron beam irradiation and localized laser ablation of the grafted polymer. Poly(N-isopropylacrylamide) (PIPAAm) was covalently grafted to surfaces of tissue culture-grade polystyrene dishes. Subsequent ultraviolet ArF excimer laser exposure to limited square areas (sides of 30 or 50 m) produced patterned ablative photodecomposition of only the surface region (ϳ100-nm depth). Three-dimensional surface profiles showed that these ablated surfaces were as smooth and flat as the original tissue culture-grade polystyrene surfaces. Time-of-flight secondary ion mass spectrometry analysis revealed that the ablated domains exposed basal polystyrene and were surrounded with PIPAAmgrafted chemistry. Before cell seeding, fibronectin was adsorbed selectively onto ablated domains at 20°C, a condition in which the non-ablated grafted PIPAAm matrix remains highly hydrated. Hepatocytes seeded specifically adhered onto the ablated domains adsorbed with fibronectin. Because PIPAAm inhibits cell adhesion and migration even at 37°C when the grafted density is Ͼ3 g/cm 2 , all the cells were confined within the ablated domains. A 100-cell domain array was achieved by this method. This surface modification technique can be utilized for fabrication of cellbased biosensors as well as tissue-engineered constructs.

In order to investigate weak link properties in the Tl1Ba2Ca2Cu3Ox[Tl-(1223)] system, we measured the transport properties of artificially grown grain boundaries in Tl-(1223) films. Epitaxial thin films were grown on SrTiO3 bicrystal substrates with five tilt angles of 5°, 10°, 15°, 24°, and 36.8°. We found that the grain boundaries Jc (Jcg.b.) of large tilt angles (θ≥15°) at 77 and 5 K were substantially less than intragrain Jc(Jcg) and limited by a weak link. However, the Jcg.b./Jcg values for low tilt angle grain boundaries (θ≤10°) were almost unity. Moreover, magnetic-field history dependent Jc values for low tilt angle grain boundaries were not observed in a low magnetic field (<0.1 T). These data indicate that the low tilt angle grain boundaries do not work as a weak link and retain high Jc.