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371.
Using the most recent differential cross section data for e-p quasi-elastic scattering, the charged pion formation and its form factor Fπ is calculated in the energy range of 2.4-4 GeV at Q^2 = 0.6-1.6 (GeV/c)^2. The functional dependence of the charged pion form factor to the separated cross section aL is investigated and compared to the previously determined result.  相似文献   
372.
Transport in Porous Media - No matter how sophisticated the structures are and on what length scale the pore sizes are, fluid displacement in porous media can be visualized, captured, mimicked and...  相似文献   
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The viscoelastic behaviour of a number of commercial and newly synthesized linear biodegradable polyesters—poly (ε-caprolactone) (PCLs) with different molecular characteristics was investigated using both rotational and extensional rheometry. The variation of the zero-shear viscosity and relaxation spectrum with molecular weight was studied in detail. The damping function of these PCLs was also determined in order to model their viscoelastic behaviour. The classic Wagner constitutive equation was found to represent the rheology of all PCL polymers quite well. Finally, the PCL processing instabilities were studied by capillary extrusion using a number of capillary dies having various diameter and length-to-diameter ratios. Sharkskin and gross melt fracture was observed at different shear rates depending on the molecular characteristics of the resins and the geometrical details of the capillary dies.  相似文献   
374.

Quantum dot cellular automata (QCA) is one of the nano-scale computing paradigms which promises high speed and ultra-low power consumption. Since the one-bit full adder is a fundamental building block of arithmetic circuits, designing an efficient QCA full adder cell is very imperative in this new technology. In this paper, we propose a QCA full adder using a new inverter gate which leads to reduced complexity and area occupation. The proposed layout is simulated by the QCA designer engines. We also provide a performance comparison of our proposed QCA full adder with the previous relevant designs. Furthermore, a detailed analysis of energy dissipation is performed which demonstrates the superiority of the proposed design in terms of the energy efficiency.

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375.
4-(Succinimido)-1-butane sulfonic acid was shown to be anefficient and reusable Br?nsted acid catalyst for the synthesis of pyrano[4,3-b]pyran derivatives using thermal and ultrasonic conditions. The c...  相似文献   
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Palm leaf ash was characterized and used as low‐cost adsorbent for solid‐phase extraction and preconcentration of bisphenol A (BPA) in real water samples. Analysis of BPA was carried out using HPLC involving Eurospher 100–5‐C18 (25 cm × 4.5 mm, particle size 5 μm) column and water–acetonitrile (40:60, v/v) as mobile phase. The adsorption was achieved quantitatively at a pH of 6 with elution by 3 mL acetonitrile. The limits of detection and enrichment factor were 0.02 μg L?1 and 333, respectively. Under optimum conditions the relative standard deviation (RSD) was 2% (n = 10). Comparison of qualification criteria of presented preconcentration procedure with other research indicated that palm leaf ash adsorbent was better than many of the adsorbents in terms of cost and reusability. Also, the limit of detection, precision and enrichment factor were comparable and even better than the previously reported methods. Finally, the efficiency of method was computed by determination of trace amounts of BPA in sea, river, mineral and tap waters with recoveries of 93.3–105.5% and RSDs of 0.61–3.12%.. Briefly, the developed solid‐phase extraction and Preparative layer chromatography (PLC) methods may be used for bisphenol A monitoring in any environmental water sample. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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This paper presents a theoretical and numerical investigation of the interaction between sound waves and non-diffusive, quasi-one-dimensional, subsonic flows with only steady heat communication. It is first shown that a steady heat communicating flow can attenuate or generate sound even in the absence of mean flow acceleration. The relative significance of sound generation by the heat addition induced acceleration of density or entropy inhomogeneities and the effect of steady heat communication on the incident acoustic wave is then found. It is shown through scaling arguments that at high frequencies mean flow acceleration effects are negligible and the only significant sound generating mechanism involves steady heat communication. At low frequencies, however, the two mechanisms are more comparable.  相似文献   
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