Top PDF Electric field enhancement of efficiency in autoradiographic exposures

Electric field enhancement of efficiency in autoradiographic exposures

Electric field enhancement of efficiency in autoradiographic exposures

ELECTRIC OF FIELD ENHANCEMENT EFFICIENCY AUTORADIOGRAPHIC IN EXPOSURES by P- Harvey Smith Submitted to the Photographic Science and Instrumentation Division in partial fulfillment of the[r]

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Bowtie Nanoantennas with Polynomial Sides in the Excitation and Emission Regimes

Bowtie Nanoantennas with Polynomial Sides in the Excitation and Emission Regimes

In this paper, we presented a theoretical analysis of modified bowtie nanoantennas with polynomial sides in the excitation and emission regimes. We observed in the excitation regime that the resonances of the modified antennas are shifted to higher wavelengths and the electric field in the middle of the gap’s antenna is increased, where it presents only polarization along the axis of the dipoles. Also, the field confinements of the modified antennas are higher than the conventional one. In the emission mode, we noted that the maximum radiation efficiency of all antennas occurs at the same resonant wavelengths obtained in the excitation regime, and the values of these efficiencies, for the modified antennas, are smaller than those of the conventional one with the same dimensions, but it can be increased for larger antenna’s size and gap distances between the arms of the dipoles. With respect the directive properties of these antennas, all the cases analyzed presented directivities similar to that of an electrically small antenna. With all these results, we conclude that the modified bowtie nanoantennas have higher near field enhancement and confinement, and smaller radiation efficiency than those of the conventional bowtie antenna with linear sides. With appropriately chosen dimensions, these novel nanoantennas can be used, for example, to enhance the spontaneous emission of single molecules positioned in the middle of the antenna’s gap. Future works can be the analysis the characteristics dependence of these antennas on the thickness, orientation of the incident plane wave, and the polarization of the emitter in the gap. ACKNOWLEDGMENT
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The enhancement of residual electric field in water electrolysis by green laser irradiation

The enhancement of residual electric field in water electrolysis by green laser irradiation

This research is carried out to investigate the influence of green laser irradiation to electrolysis efficiency during water electrolysis. Conventional electrolysis usually takes longer time to produce hydrogen, while in industrial hydrogen manufacture, the high production cost and environmental problems are unavoidable. By introducing laser electrolysis (an employment of laser as a light source during water electrolysis), the weak residual electric field during conventional electrolysis can be solved. This is due to the coherent properties of the laser light that related to the polarization of the light. As the polarization of the laser light is high, the amplitude of the electric field carried by the laser is high. Thus, the hydrogen production during laser electrolysis could be enhanced. It is considered as an efficient method in producing pure hydrogen for commercial purposes.
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Surface Plasmon Resonance of a Few Particles Linear Arrays

Surface Plasmon Resonance of a Few Particles Linear Arrays

The possible use of visible light to observe directly nano- systems has been opened by means of the mechanism of optical nano-imaging based on the excitation of SPP- Surface Plasmon Polariton, which breaks the diffraction limit of light and offers a resolution beyond a value comparable to the wavelength of the applied light [1,2]. Surface plasmons (SPs) are states of polarization that can propagate along metal-dielectric interfaces without radia- tive losses. Polarization in an SP excitation can be spa- tially confined on scales that are much smaller than the free-space wavelength. This property proved to be extre- mely valuable for manipulation of light energy on subwa- velength scales and miniaturization of optical elements. SP excitations in ordered one-dimensional arrays of nano- particles have attracted significant attention in recent ye- ars due to numerous potential applications in nanoplas- monics. The interesting behavior of light under the influ- ence of plasmons not only allows superlensing [3,4], in which perfect imaging is possible through a flat thin metal film, plasmonic antennas and lenses can convert optical radiation into intense, engineered, localized field distribu- tions or enable coupling to deep subwavelength guided modes. Thus, wherever subwavelength control over light
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Measurement of the Shielding Effectiveness of Conducting Enclosures with the Image Theory

Measurement of the Shielding Effectiveness of Conducting Enclosures with the Image Theory

Abstract. Two simple techniques for the measurement of the shielding efficiency for the electric field of a symmet- ric enclosure are presented.y They allow measurements in the symmetry plane of the enclosure without disturbances b the cables. Measurements in near and far field regions are possible. Comparisons with simulation results are shown. Both techniques are particularly suitable for the evaluation of numerical techniques. Limits of the concept of shielding efficiency of enclosures at high frequencies are also briefly discussed.

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Polarisation Coherence Imaging of Electric and Magnetic Fields in Plasmas

Polarisation Coherence Imaging of Electric and Magnetic Fields in Plasmas

Once the viewing coordinates have been determined it is possible to model the relevant parameters for the view. Firstly the polarisation angle expected for either view can be modelled by calculating the direction of the motional electric field from an EFIT equilib- rium of the toroidal and poloidal magnetic fields. Line integration effects from the IMSE view are significant given that the neutral beams have a non-negligible 14cm full width at half maximum in the horizontal direction[12]. The radial sightlines from the 15 ◦ port in- tersect the neutral beam over a large range of radii and flux surfaces unlike the 315 ◦ view, as evident in Fig. 4.1 and later in Fig. 4.6. An indicator of this line integration width is given in Fig. 4.5 for the IMSE view of both the 30L and 30R beams as well as a comparison with the tangential 315 ◦ MSE view of the 30L beam. The plot is comparable to the plot in Ref. [68] that compares the radial resolution of the 315 ◦ and 45 ◦ MSE ports. It is well known that views of the neutral beam that are approximately tangent to the flux surfaces are preferred, such as the 315 ◦ view which is tangent to the flux surfaces at R = 1.67m and therefore the radial resolution is optimal. On the other hand the δr ∼ 20cm range of flux surfaces that are integrated/averaged over for the IMSE sightlines will blur any sharp features in the q-profile. While the radial resolution inherent to the IMSE port is far from ideal, it should be noted that the port was chosen for this experiment due to port availability and the view having a relatively straightforward window calibration (using previous Faraday rotation measurements and the view is free of mirrors) given in-vessel or beam-into-gas calibration opportunities weren’t possible for the short campaign.
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Analytical technique for electroelastic field in piezoelectric bodies belonging to point group D
              ∞

Analytical technique for electroelastic field in piezoelectric bodies belonging to point group D ∞

dielectric constant, and piezoelectric constant, respectively. Equations (2) and (3) are derived in Appendix 1. The components of stress and electric displacement are chosen as dependent variables in Eqs. (2) and (3) because the governing equations are described in terms of those com- ponents as shown later in Eqs. (7) and (8). Here, by denoting

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Electrical tuning of nonlinearities in exciton polariton condensates

Electrical tuning of nonlinearities in exciton polariton condensates

A unique opportunity to enhance such dipole exciton- polariton interactions is provided through application of an electric field across the MC device. The applied field pushes electrons and holes inside the QW in opposite directions and induces exciton dipole moment oriented along the growth axes as shown in Fig. 1(b). We quantify the effect of bias on the MC, by solving the Schrodinger equation in combination with a variational method for the excitons [16, 17] to extract the heavy hole (HH) and light hole (LH) exciton oscillator strengths and thus radiative times [Fig. 2(a)], dipole moment [Fig 2(a)] and excitonic Bohr radius and the exciton inter- action strength constant g x [18] [Fig. 2(b)] as a function of
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14. Electric Forces and Fields

14. Electric Forces and Fields

electric field patterns is to draw lines pointing in the direction of the field vector at any point.  These are called electric field[r]

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ROLE OF HIGH TEMPERATURE SUPERCONDUCTING MATERIALS FOR INNOVATIONS AND TECHNOLOGY

ROLE OF HIGH TEMPERATURE SUPERCONDUCTING MATERIALS FOR INNOVATIONS AND TECHNOLOGY

HTSrs in Power generation will reduce technical power losses, which are given conventional conductor and obsolete mechanical designs. Conventional conductor winding wires are heavy and oversize. So, excess load due to technical power losses discharges additional air, water and land pollution from thermal power generation units. The wastage of unit power by power energy efficiency of power utility and power generation process release about 1.5kg CO 2 and other pollutants. But superconductor wire, bars and tapes will reduce electrical
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16 Static Electricity.pdf

16 Static Electricity.pdf

•Describe an electric field as a region in which an electric charge experiences a force •Draw the electric field of an isolated point charge and recall that the direction of the field lines gives the direction of the force acting on a positive test charge.

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Electric field Analysis of Water Electrodes for Noninvasive Pulsed Electric field Applications

Electric field Analysis of Water Electrodes for Noninvasive Pulsed Electric field Applications

Under observation I, peak voltage was changed accordingly to obtain a desired field value of 20 kV/cm in the simulation, which was considered as the nominal field required for bacterial inactivation. Under observation II, when compared with electrodes without surface material, a 10 kV of peak voltage is sufficient to obtain 20 kV/cm of field in the inactivation area at a distance of 5mm between the electrodes. But, if peak value of 10 kV was applied across the electrodes under the presence of surface material, 100% field application cannot be achieved. However, electric field lesser than 20 kV/cm can still be used under laboratory scale for successful microbial inactivation. The data is shown in Table III. This will enhance the understanding on percentage field reduction from high voltage to ground electrode when it travels through the surface material and will enable us to decide the suitability of material for noninvasive PEF applications.
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Accurate Computation of Electric Field Enhancement Factors for Metallic Nanoparticles Using the Discrete Dipole Approximation

Accurate Computation of Electric Field Enhancement Factors for Metallic Nanoparticles Using the Discrete Dipole Approximation

In summary, we have modeled the response of a nano- scale Ag prolate spheroid to an external electric field using DDA-based simulations that employ subunit polarizabili- ties that either include or omit a local environmental cor- rection. We invoke the electrostatic approximation, in which the incident field is assumed to be spatially uniform and static, but the spheroid’s dielectric constants is taken from the wavelength-dependent dielectric function of bulk Ag; this allows us to compare the predictions of the DDA- based simulations to exact results obtained by solving Laplace’s equation for prolate spheroids in a uniform static external field. We have chosen a dielectric constant for the
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NUMERICAL INVESTIGATION OF JUNCTION TEMPERATURE EFFECT ON DC PARAMETERS OF SILICON IMPATT DEVICE

NUMERICAL INVESTIGATION OF JUNCTION TEMPERATURE EFFECT ON DC PARAMETERS OF SILICON IMPATT DEVICE

Increase of electric field will cause the increase of breakdown voltage, and since field increases with increasing temperature at a particular current density, so breakdown voltage increase due to the same physical effect. Also at a particular junction temperature, breakdown voltage slowly increases almost in a resistive fashion. Due to this combined factor, conversion efficiency drastically decreases with increasing current density, and ultimately becomes equal to the efficiency of SDR device designed with same doping concentration. Also increasing junction temperature has a profound effect on efficiency and it reduces with higher temperature, as evident from fig 9.
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AC Voltage Induced Electrohydrodynamic Two Phase Convective Boiling Heat Transfer in Horizontal Annular Channels

AC Voltage Induced Electrohydrodynamic Two Phase Convective Boiling Heat Transfer in Horizontal Annular Channels

Similar to observed DC influences that tend to increase the upper temperature variation at location 1, the migration, deformation and breaking of vapour bubbles in the flow are the main contributing factors augmenting bubble dynamics and as a consequence the wall temperature variation in this region. By combining the dynamic effects of the 60 Hz electric field strength variation with the various EHD effects on nucleate boiling, these influences are expected to be accentuated, thereby increasing the temperature variations accordingly. This is corroborated by the recent work of Liu et al [39] and Siedel et al [40] who have shown, respectively, that EHD can significantly augment the heat transfer and bubble dynamics during nucleate pool boiling.
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CrFe2O4 - BiFeO3 Perovskite Multiferroic Nanocomposites – A Review

CrFe2O4 - BiFeO3 Perovskite Multiferroic Nanocomposites – A Review

hours. Initially this solution was started to swell and filled the beaker by producing a foamy precursor. This foam contains light and homogeneous flakes of tiny particles. The formation of BiFeO 3 is checked by XRD technique with Cu K a radiation (l=0.15418 nm), using a BRuKER D8 XRD spectroscope. The surface grain distribution and composition analysis of BiFeO 3 samples were studied using Field Emission Scanning electron micrographs (FESEM), Quanta 200 attached with Energy dispersion X-ray spectrometer (EDAX). Thermo-gravimetric (TG) and differential thermal gravimetric analysis are conducted and checked the stability and phase transformation in the samples. To study ferroelectric hysteresis behavior, a modified Sawyer–Tower circuit is used.
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Laser induced damage due to scratches in the surface of nonlinear optical crystals KH2PO4 (KDP)

Laser induced damage due to scratches in the surface of nonlinear optical crystals KH2PO4 (KDP)

Figure 9 shows the maximal light intensity enhancement for two kinds of scratches with respect to the width of scratches when width-to-depth ratio keeps constant. The width-to-depth ratios are 2 and 20, respectively. It can be seen from Fig. 9b that the maximal light enhancement is more significant for elliptical scratches than triangular ones for the ratio of 20. This discrepancy increases with the width of scratches. The light enhancement is nearly linearly proportional to the width of scratches while it is almost unchanged for triangular scratches when the width of scratches exceeds 3 μm in the modeled situations. By con- trast, the triangular ones affect the light intensity more than elliptical ones in the case of width-to-depth ratio 2. The critical width-to-depth ratio is dependent on the width of scratches, see below. For micro-cracks usually with width-to-depth far much less than 1, the light field intensi- fication is more severe than those with rounded tips.
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Effect of Incidence Angle Varying from 0 rad to π/2 rad and Intensity of Radio Waves on the Performance of a Silicon Solar Cell

Effect of Incidence Angle Varying from 0 rad to π/2 rad and Intensity of Radio Waves on the Performance of a Silicon Solar Cell

This study also showed that for an incidence angle such as θ=0 rad, the leakage photocurrent density and the open circuit electric power de- crease strongly until their cancellation with the increase of the distance between the solar cell and the radio antenna. The numerical data are evi- dence of a decrease in the maximum electric pow- er and the conversion efficiency with the increase of the distance between the solar cell and the ra- dio antenna while the shunt resistance increases. The solar cell studied in this article is an ideal solar cell and so the leakage photocurrent density and the open circuit electric power at the junction interface are neglected resulting in a high value of the shunt resistance. Consequently, the presence of a leakage photocurrent density and an open cir- cuit electric power at the junction interface leads to a reduction of the shunt resistance and a Joule effect. The decrease of the shunt resistance and the Joule effect affect the quality of the junction of a solar cell and so its working. Therefore, solar cells have to be far from radio antennas or tele- communication antennas which are able to create strong electromagnetic fields.
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Electric field enhancement in ceramic capacitors due to interface amplitude roughness

Electric field enhancement in ceramic capacitors due to interface amplitude roughness

The electrical characterisation of the interfaces was simulated using the finite element method (FEM). The in-house code used in this study, solves for the electric potential (ϕ) in the time domain using the Galerkin scheme for time discretisation. By assuming each material simulated is linear, isotropic and has no time dispersion, the potential can be solved as function of space (r) and time (t) for given values of conductivity (σ) and permittivity (ε) assigned to the elements of the mesh. This allows conductive and Debye relaxations to be simulated. To replicate electrical measurements a potential difference is applied to model using a Dirichlet boundary condition (known values of potential at the top and bottom of the model). The local current density (j) is solved as function of potential using equation (1):
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Electrically tunable, optically induced dynamic and permanent gratings in dye doped liquid crystals

Electrically tunable, optically induced dynamic and permanent gratings in dye doped liquid crystals

As reported in earlier studies [14], [28], [29] of methyl-red- doped nematic liquid crystals (MRNLC), these films exhibit unusually large static space charge fields and photo-voltages. Under an optical intensity of 1 mW/cm , photo voltages of sev- eral millivolts are produced. Also, the materials become more conductive. These photo-induced space charge fields, in con- junction with an applied dc or low-frequency ac field, have been shown to play an important role in initiating the director axis re- orientation [2]–[5], besides the inter-molecular torque produced by the excited dye dopant molecules. Accordingly, we expect that that an applied field will influence the reorientation grating and therefore the grating diffraction efficiency.
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