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Notes: The feasibility of a high-temperature superconducting switch based on the principle of the superconducting vector switch (SVS) is discussed. This switch exploits the anisotropy in electrical conductivities of the high-temperature superconductors. Underlying the SVS mechanism is the ability to turn on/off large superconducting currents confined to the CuO2 planes that characterize these materials using lower currents flowing normal to the planes. The required conditions to optimize the switch and increase the gain are presented.

Notes: The changed flow pattern of pulsatile blood flow in an annulus with elastic outer wall has been studied through a mathematical model. The main objective is to apply the model to study the combined effect of introduction of the catheter and elastic properties of the arterial wall on the pulsatile nature of the blood flow. The diameter variation of the wall is considered small for the perturbation analysis to be valid. The steady streaming effect brings into focus the existence of a nonzero mean pressure gradient in addition to the one predicted by the linear theory—a fact overlooked by previous authors. Thus, our results are intended to provide a correction to the "mean pressure gradient–flow rate relationship" usually calculated by neglecting the nonlinear inertia terms. This correction depends on the amplitude of the diameter variation, flow rate wave forms, and the phase difference between them. The calculations based on the geometry and the flow conditions representing a real physiological situation as closely as possible suggest that mean pressure gradient changes with catheter size for any frequency parameter. The results obtained for arbritrary frequency parameter and for small steady streaming Reynolds number, Rst, show that the geometry of the wall plays an important role in the dynamics of the flow even for small catheter radius. The interaction of the amplitude of catheter oscillation and the amplitude of the wall movement is first manifested through the induced mean pressure gradient and induced mean velocity. Further, the results are sensitive to the elastic nature of the wall reflected by the phase difference between the diameter variation and the flow rate. Interesting streamline patterns depict distinct boundary layer characteristics both at artery wall and catheter wall. Depending upon the material properties, a thin catheter experiencing small oscillations due to the flow conditions is likely to have a similar influence to a thicker catheter which remains fairly stationary inside the artery. Finally, the effect of catheterization on various physiologically important flow rate characteristics—mean velocity, mean pressure gradient, wall shear stress—is studied for a range of different catheter sizes and frequency parameters. © 2001 American Institute of Physics.

Notes: A simple single-source electron-beam evaporation technique has been used for the deposition of lead-lanthanum-zirconate-titanate (PLZT) thin films for silicon-based device applications. An optimized annealing condition has been established for the formation of crystalline perovskite phases. The effect of the bottom electrodes and the barrier layer on the growth of the films has been studied. Films with good dielectric and optical properties have been obtained under opt- imized conditions. Electrical properties of the films have been evaluated using metal–insulator–semiconductor and metal–insulator–metal structures. A moderately low interface trap density and very low leakage current density demonstrate the potential of the deposited films for device applications. © 1996 American Institute of Physics.

Notes: Stable oxygen and carbon isotope ratios (δ18O and δ13C, respectively) of a planktonic foraminiferal species (Globigerinoides sacculifer) and marble carbonate were measured with and without a variety of pretreatments like ultrasonication, soaking in H2O2, methanol and roasting under vacuum. Additionally, organic matter - carbonate mixtures were also analysed with and without the above pretreatments. No significant difference was found in the isotope ratios of treated and untreated samples. It appears that most of the pretreatments may not be necessary when dealing with planktonic foraminifera, especially G. sacculifer. Analysis of two different size fractions (〉 400 μm and 250–400 μm) of this species reveals that the smaller size fraction is enriched in 18O and depleted in 13C relative to the bigger size fraction. It is therefore necessary to choose a proper size fraction for isotopic analyses.

Notes: Oxygen and carbon isotopes were measured to a high depth resolution in a nannoplankton carbonate sequence spanning the Cretaceous-Tertiary boundary at Koshak Hill, Mangyshlak Peninsula, Kazakhstan. The boundary is characterized by the presence of a ∼ 1 cm thick clay layer having a sharp peak in iridium concentration with a maximum value of 3.7 ng g-1. The δ18O data reveal rapid (∼103 years) excursion of sea-surface temperature at the boundary where an initial cold pulse is followed by a persistent warm period. The δ13C data, in contrast, indicate only a gradual change in productivity across the boundary. The observations suggest a biogeochemical scenario for the boundary event pertaining to shallow epicontinental seas.

Notes: Rheological properties of cooked noodles made on a small-scale laboratory sheeting machine developed at the Cereal Research Centre were strongly correlated with the same properties of noodles made on a pilot noodle sheeting machine. Values obtained from both machines were evaluated against 22 laboratory tests used in our breeding program. For example, cooked noodle viscoelasticity (r=0.89, P 〈 0.01) and cooked noodle cutting force (r = 0.79, P 〈 0.01) were similar. Cooked noodle viscoelasticity of fresh noodles made on the laboratory machine correlated significantly (P 〈 0.05) with 17 of the tests and cooked noodle cutting force correlated significantly with 18 tests. Cooked noodle viscoelasticity of dried noodles made with the pilot plant noodle machine had significant correlations (P 〈 0.05) with only 14 of the tests and cooked noodle cutting force had significant correlations with 15 tests. The pilot plant machine requires a minimum of 500 g for one sample, while the small-scale sheeting machine requires only 5-10 g of flour.