Nanoparticles at the Polydimethylsiloxane Droplet/Water Interface

2005 ◽  
Vol 58 (9) ◽  
pp. 664 ◽  
Author(s):  
Spomenka Simovic ◽  
Clive A. Prestidge
Keyword(s):  
Electrical Properties ◽  
Layer Structure ◽  
Water Interface ◽  
Adsorption Behaviour ◽  
Nanoparticle Layer ◽  
Hydrophobically Modified ◽  
Salt Addition ◽  
Wide Range ◽  
Droplet Stability ◽  
Water Transport Properties

The adsorption behaviour of nanoparticles at the polydimethylsiloxane droplet/water interface and the influence of particle hydrophobicity, droplet deformability, and the surface electrical properties of both particles and droplets (as controlled by pH and salt concentration) are reported. Adsorption of hydrophilic nanoparticles is weakly influenced by pH but significantly influenced by salt addition, whereas for hydrophobically modified nanoparticles a balance of hydrophobic and electrostatic forces controls adsorption over a wide range of pH and salt concentrations. The relationships between the adsorbed nanoparticle layer structure, droplet stability, and the oil-to-water transport properties have also been elucidated.

Linear electrical properties of striated muscle fibres observed with intracellular electrodes

1964 ◽  
Vol 160 (978) ◽  
pp. 69-123 ◽  
Keyword(s):  
Electrical Properties ◽  
Striated Muscle ◽  
Surface Membrane ◽  
Fibre Surface ◽  
Step Function ◽  
Muscle Fibres ◽  
Appreciable Effect ◽  
Current Application ◽  
Current Path ◽  
Wide Range

The linear electrical properties of muscle fibres have been examined using intracellular electrodes for a. c. measurements and analyzing observations on the basis of cable theory. The measurements have covered the frequency range 1 c/s to 10 kc/s. Comparison of the theory for the circular cylindrical fibre with that for the ideal, one-dimensional cable indicates that, under the conditions of the experiments, no serious error would be introduced in the analysis by the geometrical idealization. The impedance locus for frog sartorius and crayfish limb muscle fibres deviates over a wide range of frequencies from that expected for a simple model in which the current path between the inside and the outside of the fibre consists only of a resistance and a capacitance in parallel. A good fit of the experimental results on frog fibres is obtained if the inside-outside admittance is considered to contain, in addition to the parallel elements R m = 3100 Ωcm 2 and C m = 2.6 μF/cm 2 , another path composed of a resistance R e = 330 Ωcm 2 in series with a capacitance C e = 4.1 μF/cm 2 , all referred to unit area of fibre surface. The impedance behaviour of crayfish fibres can be described by a similar model, the corresponding values being R m = 680 Ωcm 2 , C m = 3.9 μF/cm 2 , R e = 35 Ωcm 2 , C e = 17 μF/cm 2 . The response of frog fibres to a step-function current (with the points of voltage recording and current application close together) has been analyzed in terms of the above two-time constant model, and it is shown that neglecting the series resistance would have an appreciable effect on the agreement between theory and experiment only at times less than the halftime of rise of the response. The elements R m and C m are presumed to represent properties of the surface membrane of the fibre. R e and C e are thought to arise not at the surface, but to be indicative of a separate current path from the myoplasm through an intracellular system of channels to the exterior. In the case of crayfish fibres, it is possible that R e (when referred to unit volume) would be a measure of the resistivity of the interior of the channels, and C e the capacitance across the walls of the channels. In the case of frog fibres, it is suggested that the elements R e , C e arise from the properties of adjacent membranes of the triads in the sarcoplasmic reticulum . The possibility is considered that the potential difference across the capacitance C e may control the initiation of contraction.

scholarly journals Preparation and Electrical Properties of Modulation-doped ZnO Multi-layer Structure

2003 ◽  
Vol 50 (4) ◽  
pp. 292-296
Author(s):  
Yutaka Adachi ◽  
Naoki Ohashi ◽  
Isao Sakaguchi ◽  
Hajime Haneda ◽  
Haruki Ryouken ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Layer Structure ◽  
Doped Zno

scholarly journals Novel Bloch wave excitation platform based on few-layer photonic crystal deposited on D-shaped optical fiber

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Esteban Gonzalez-Valencia ◽  
Ignacio Del Villar ◽  
Pedro Torres
Keyword(s):  
Optical Fibers ◽  
High Performance ◽  
Light Propagation ◽  
Fiber Optic ◽  
Layer Structure ◽  
Optical Network ◽  
Building Blocks ◽  
Bloch Wave ◽  
Nanophotonic Devices ◽  
Wide Range

AbstractWith the goal of ultimate control over the light propagation, photonic crystals currently represent the primary building blocks for novel nanophotonic devices. Bloch surface waves (BSWs) in periodic dielectric multilayer structures with a surface defect is a well-known phenomenon, which implies new opportunities for controlling the light propagation and has many applications in the physical and biological science. However, most of the reported structures based on BSWs require depositing a large number of alternating layers or exploiting a large refractive index (RI) contrast between the materials constituting the multilayer structure, thereby increasing the complexity and costs of manufacturing. The combination of fiber–optic-based platforms with nanotechnology is opening the opportunity for the development of high-performance photonic devices that enhance the light-matter interaction in a strong way compared to other optical platforms. Here, we report a BSW-supporting platform that uses geometrically modified commercial optical fibers such as D-shaped optical fibers, where a few-layer structure is deposited on its flat surface using metal oxides with a moderate difference in RI. In this novel fiber optic platform, BSWs are excited through the evanescent field of the core-guided fundamental mode, which indicates that the structure proposed here can be used as a sensing probe, along with other intrinsic properties of fiber optic sensors, as lightness, multiplexing capacity and easiness of integration in an optical network. As a demonstration, fiber optic BSW excitation is shown to be suitable for measuring RI variations. The designed structure is easy to manufacture and could be adapted to a wide range of applications in the fields of telecommunications, environment, health, and material characterization.

Influence of Nitrogen Implantation on Electrical Properties of Al/SiO2/4H-SiC MOS Structure

2013 ◽  
Vol 740-742 ◽  
pp. 733-736 ◽  
Author(s):  
Krystian Król ◽  
Mariusz Sochacki ◽  
Marcin Turek ◽  
Jerzy Żuk ◽  
Henryk M. Przewlocki ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Electrical Properties ◽  
Surface State ◽  
Material Properties ◽  
Implantation Dose ◽  
Nitrogen Implantation ◽  
Mos Structure ◽  
Implantation Damage ◽  
Wide Range ◽  
Implantation Dosage

In this article, an influence of nitrogen implantation dosage on SiC MOS structure is analyzed using wide range of nitrogen implantation dose (between ~1013 – 1016). Authors analyzed electrical and material properties of investigated samples using C-V, I-V measurements, Raman spectroscopy, and XPS profiling. It has been shown that surface state trap density is directly connected to implantation damage and thus implantation conditions. Using research results a trap origin at given energy can be concluded.

scholarly journals Measurements of adsorption at the air-water interface by the microtome method

1936 ◽  
Vol 154 (883) ◽  
pp. 608-623 ◽  
Keyword(s):  
Dynamic Method ◽  
Fundamental Importance ◽  
Molecular Adsorption ◽  
Water Interface ◽  
Experimental Demonstration ◽  
Gibbs Equation ◽  
Experimental Conditions ◽  
Moving Surface ◽  
Wide Range ◽  
Air Water Interface

In spite of the wide use and fundamental importance of the classical Gibbs adsorption theorem, its validity has never been given adequate experimental demonstration. Until quite recently the principal means available for testing this theorem was the “moving bubble method”, developed by Donnan and Barker, and later by McBain, Davies, and DuBois. Almost without exception this method has given results many times greater than the values calculated from either the exact or the approximate Gibbs equation. A recent exhaustive investigation of this dynamic method by DuBois and Todd has shown, moreover, that the results for moving bubbles may be varied and controlled over a wide range by merely altering the size or speed of the bubbles or the amount of accompanying liquid. Thus the results, although definite and repro­ducible, vary greatly with the experimental conditions, and hence they bear no definite relation either to the Gibbs value or to that for mono-molecular adsorption. It is evident that a moving surface carries in general an amount of adsorbed material which is much greater than that predicted by the Gibbs theorem. Similar high results are reported by Seymour, Tartar, and Wright for moving droplets of benzene in water, which may carry with them as much soap as would correspond to twenty or more mono-layers.

The Climatology, Meteorology, and Boundary Layer Structure of Marine Cold Air Outbreaks in Both Hemispheres*

2016 ◽  
Vol 29 (6) ◽  
pp. 1999-2014 ◽  
Author(s):  
Jennifer Fletcher ◽  
Shannon Mason ◽  
Christian Jakob
Keyword(s):  
Boundary Layer ◽  
Layer Structure ◽  
Zonal Flow ◽  
Heat Fluxes ◽  
Pressure Gradients ◽  
Cold Air ◽  
Surface Heat Fluxes ◽  
Cold Air Outbreak ◽  
Wide Range ◽  
Cold Air Outbreaks

Abstract A comparison of marine cold air outbreaks (MCAOs) in the Northern and Southern Hemispheres is presented, with attention to their seasonality, frequency of occurrence, and strength as measured by a cold air outbreak index. When considered on a gridpoint-by-gridpoint basis, MCAOs are more severe and more frequent in the Northern Hemisphere (NH) than the Southern Hemisphere (SH) in winter. However, when MCAOs are viewed as individual events regardless of horizontal extent, they occur more frequently in the SH. This is fundamentally because NH MCAOs are larger and stronger than those in the SH. MCAOs occur throughout the year, but in warm seasons and in the SH they are smaller and weaker than in cold seasons and in the NH. In both hemispheres, strong MCAOs occupy the cold air sector of midlatitude cyclones, which generally appear to be in their growth phase. Weak MCAOs in the SH occur under generally zonal flow with a slight northward component associated with weak zonal pressure gradients, while weak NH MCAOs occur under such a wide range of conditions that no characteristic synoptic pattern emerges from compositing. Strong boundary layer deepening, warming, and moistening occur as a result of the surface heat fluxes within MCAOs.

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