Journal articles: 'Dielectric CCD'

1

Deb, K. K., M. D. Hill, and J. F. Kelly. "Pyroelectric characteristics of modified barium titanate ceramics." Journal of Materials Research 7, no. 12 (December 1992): 3296–305. http://dx.doi.org/10.1557/jmr.1992.3296.

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BaZrO3 and BaHfO3 modified polycrystalline BaTiO3 are candidate materials for transverse mode and pyroelectric charge coupled device (CCD) arrays. Addition of 3–4% barium zirconate and barium hafnate to barium titanate alters the temperature of phase transformations and with it, dielectric and pyroelectric properties. These additions create a temperature range close to room temperature where the pyroelectric coefficient is extremely high relative to the dielectric permittivity. These materials show a very high figure of merit for dielectric bolometer applications that is competitive with existing materials, while being relatively easy to prepare.

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Tao, Chunxian, Jun Ruan, Dong Liang, Zhaoxia Han, Liang He, Ruijin Hong, Xiao Cui, and Dawei Zhang. "Enhancement of UV Excited Photoluminescence by Fabry-Perot Microcavity." Journal of Spectroscopy 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/153483.

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A light-emitting microcavity with the structure of dielectric mirror/phosphor coating/dielectric mirror for the enhancement of PL efficiency excited under UV light was designed and fabricated. The fluorescence emission of Lumogen S0795 coating within microcavity structure is significantly enhanced compared with the coating on bare substrate. The measurement results indicate the possibility of developing front illuminated CCD based on optical resonant cavity for UV-visible imaging with higher sensitivity.

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Čech, Jan, Miroslav Zemánek, Pavel Sťahel, Hana Dvořáková, and Mirko Černák. "INFLUENCE OF SUBSTRATE THICKNESS ON DIFFUSE COPLANAR SURFACE BARRIER DISCHARGE PROPERTIES." Acta Polytechnica 54, no. 6 (December 31, 2014): 383–88. http://dx.doi.org/10.14311/ap.2014.54.0383.

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In presented work the influence of dielectric barrier thickness on the parameters of Diffuse Coplanar Surface Barrier Discharge was investigated. The discharge was operated at atmospheric pressure laboratory air. The electrical parameters of the system were studied both experimentally and using numerical simulations. The discharge pattern was studied as well using intensified CCD camera.

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Okuyama, M., Y. Togami, Y. Hamakawa, M. Kimata, and M. Denda. "Room-temperature-operated infrared image CCD sensor using pyroelectric gate coupled by dielectric connector." IEEE Transactions on Electron Devices 38, no. 5 (May 1991): 1145–51. http://dx.doi.org/10.1109/16.78392.

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Taleb, Soumia Imane, Cristian Neipp, Jorge Francés, Andrés Márquez, Mariela L. Alvarez, Antonio Hernández, Sergi Gallego, and Augusto Beléndez. "Validation of Fresnel–Kirchhoff Integral Method for the Study of Volume Dielectric Bodies." Applied Sciences 11, no. 9 (April 22, 2021): 3800. http://dx.doi.org/10.3390/app11093800.

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In this work, we test a nondestructive optical method based on the Fresnel–Kirchhoff integral, which could be applied to different fields of engineering, such as detection of small cracks in structures, determination of dimensions for small components, analysis of composition of materials, etc. The basic idea is to apply the Fresnel–Kirchhoff integral method to the study of the properties of small-volume dielectric objects. In this work, we study the validity of this method. To do this, the results obtained by using this technique were compared to those obtained by rigorously solving the Helmholtz equation for a dielectric cylinder of circular cross-section. As an example of the precision of the method, the Fresnel–Kirchhoff integral method was applied to obtain the refractive index of a hair by fitting the theoretical curve to the experimental results of the diffraction pattern of the hair measured with a CCD camera. In a same manner, the method also was applied to obtain the dimensions of a crack artificially created in a piece of plastic.

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Sikora, Wojciech. "Experimental Investigation of a Uniaxial Dielectric Elastomer Generator." Acta Mechanica et Automatica 17, no. 4 (August 17, 2023): 499–506. http://dx.doi.org/10.2478/ama-2023-0058.

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Abstract The widespread use of battery-powered electronic devices creates the need to develop methods to extend their maximum operating time. This can be achieved by using ambient energy, which would otherwise be dissipated. The conversion of energy, usually mechanical energy, into electric energy takes place in energy harvesters. Energy harvester systems based on a dielectric elastomer (DE) are a relatively new field that is being constantly developed. Due to their features, dielectric elastomer generators (DEGs) may complement the currently dominant piezoelectric harvesters. The major feature of employing a hyperelastic material is that it allows relatively large displacements to be utilised for generating energy, which is impossible in the case of piezoceramics. This article presents a DEG designed to operate under uniaxial tensile loads and which has a multilayer structure, describes the general operating principles of a DEG, explains the construction and assembly process of the investigated design and shows the electric circuit necessary to properly direct current flow during the DEG operation. The experimental part consists of two series of tests based on a central composite design (CCD). The objective of the first part was to map a capacitance response surface of the DEG in the selected range of the cyclic mechanical load. The second part concerned the amount of generated energy for the specific load case as a function of operating voltages. The result of the work is the formulation of regression models that allow the characteristics of the presented DEG design to be identified.

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Veliadis, Victor, M. Snook, H. Hearne, B. Nechay, S. Woodruff, C. Lavoie, C. Kirby, Eugene A. Imhoff, J. White, and Stuart M. Davis. "Process Tolerant Single Photolithography/Implantation 120-Zone Junction Termination Extension." Materials Science Forum 740-742 (January 2013): 855–58. http://dx.doi.org/10.4028/www.scientific.net/msf.740-742.855.

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The multiple-zone junction termination extension (MJTE) is a widely used SiC edge termination technique that reduces sensitivity to implantation dose variations. It is typically implemented in multiple lithography and implantation events. To reduce process complexity, cycle time, and cost, a single photolithography/implantation (P/I) MJTE technique was developed and diodes with 3-zone and 120-zone JTEs were fabricated on the same wafer. Here, the process tolerance of the single (P/I) MJTE technique is evaluated by performing CCD monitored blocking voltage measurements on diodes from the same wafer with the 3-zone and 120-zone single (P/I) JTE. The 3-zone JTE diodes exhibited catastrophic localized avalanches at the interface between the 2nd and 3rd zones due to abrupt zone transitions. Diodes with the smooth transitioning 120-zone JTE exhibited no CCD detectable avalanches in their JTE regions up to the testing limit of 12 kV. Under thick dielectric (deposited for on-wafer diode interconnection), diodes with the single P/I 3-zone JTE failed due to significant loss of high-voltage capability, while their 120-zone JTE diode counterparts were minimally affected. Overall, the single (P/I) 120-zone JTE provides a process-tolerant and robust single P/I edge termination at no additional fabrication labor.

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Domenicucci, A. "Image Processing Methodology for Determining SI Precipitate Size and Density in Oxide Layers from Conical Dark Field TEM Micrographs." Microscopy and Microanalysis 7, S2 (August 2001): 832–33. http://dx.doi.org/10.1017/s1431927600030233.

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Image processing techniques have been used for decades in many branches of science. with the advent of low cost, highresolution CCD cameras and the advances in personal computing, techniques previously used in other disciplines are increasingly being applied by transmission electron microscopists. The present paper gives an example of using image processing techniques for characterizing the number and size of second phase precipitates in an oxide matrix.Si inclusions in the form of Si precipitates can occur in silicon dioxide films. The inclusions are contained within the films and effectively reduce the local thickness of the oxide. This thinning results in a reduction in the voltage necessary to cause oxide breakdown; the larger is the precipitate, the lower the breakdown voltage. Knowledge of the precipitate size and density is therefore important when assessing the dielectric integrity of these films. The Si precipitates are crystalline and more or less randomly oriented within the matrix.

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Munro, Calum, Vasil Pajcini, and Sanford A. Asher. "Uv Raman Microscopy: Spectral and Spatial Selectivity and Even High Sensitivity." Microscopy and Microanalysis 3, S2 (August 1997): 835–36. http://dx.doi.org/10.1017/s1431927600011065.

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We have constructed a new UV Raman microspectrometer designed around an Olympus microscope, a single spectrograph and an intensified CCD detector (Fig. 1). We utilize CW excitation from either an intracavity frequency doubled Ar+ laser (257, 244, 229 nm) or a Kr+ laser (206 nm). We optimized the throughput by utilizing specially prepared dielectric coated Rayleigh rejection filters.In one application we used this instrument to speciate and determine the spatial distribution of non diamond carbon species in CVD diamond samples (Fig. 2). We find that these non diamond carbon species are localized in the interstitial areas between diamond crystals.In another application we demonstrated the utility of UV Raman microspectroscopy for the rapid, incisive and non-destructive characterization of meteorites and interplanetary dust particles (IDP). In addition to probing the structure and distribution of predominant mineral matrices of these materials, UV excitation enables us to the characterize the small but significant carbonaceous components included within these samples.

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Kędzierski, Jacek, Jürgen Engemann, Markus Teschke, and Dariusz Korzec. "Atmospheric Pressure Plasma Jets for 2D and 3D Materials Processing." Solid State Phenomena 107 (October 2005): 119–24. http://dx.doi.org/10.4028/www.scientific.net/ssp.107.119.

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A novel atmospheric pressure plasma jet with a cylindrical symmetry i.e. a tubular dielectric barrier and two tubular electrodes was developed at Microstructure Research Center – fmt, Wuppertal, Germany. The jet was investigated by means of ultra fast (down to tens of nanoseconds exposition time) ICCD photography and regular CCD photography. Some spectacular results were achieved and their partial explanation was presented. The jet acts as a “plasma gun” throwing small “plasma bullets” out of its orifice. The most important findings are: (i) the bullet velocity is approximately 3 orders of magnitude larger than the gas flow velocity, and (ii) the jet dynamics is mainly electrical field controlled. A simple model - formation of a jet in air - based on a Helium metastables core can explain qualitatively reasonably well most of our experimental observations. Some variations of the original cylindrical jet geometry were presented and discussed: microjet and fmt Plasma-Pen, single tube multijet, tube-in-tube single and multijet systems (so-called “Wuppertal-Approach”).

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11

Thorncroft, G. E., and J. F. Klausner. "A Capacitance Sensor for Two-Phase Liquid Film Thickness Measurements in a Square Duct." Journal of Fluids Engineering 119, no. 1 (March 1, 1997): 164–69. http://dx.doi.org/10.1115/1.2819103.

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The use of capacitance sensors for measuring liquid film thickness or phase concentration in two-phase flow has gained popularity in recent years. In designing such sensors, there are many issues which must be considered in order to optimize performance: desired temporal and spatial resolution, two-phase flow regime, permittivity of the phases, duct geometry, electrical shielding, and temperature variation in the flow field. These issues are discussed, and the design of a 12.7 mm square cross section capacitance sensor which measures liquid film thickness in either stratified are annular two-phase flow is presented. Using a composite material analysis and an effective permittivity ratio, predictive relations for capacitance as a function of liquid film thickness have been derived for stratified and annular film patterns. The analysis eliminates the need for calibrating the sensor for stratified and annular flow regimes. Optical measurements of liquid film thickness using a high resolution CCD camera are compared against those using the capacitance sensor in conjunction with the predictive relations. The sensor was tested on a bench top for a stratified film pattern with no flow and two different electrode configurations (upwards and side configurations) using FC-87, a low-permittivity (εr = 1.72) dielectric fluid. The standard deviations between the film thicknesses measured optically and those predicted using the capacitance sensor and analysis are 0.014 and 0.019 mm for the respective upward and side electrode configurations. The sensor was also implemented in a vertical flow boiling facility, which uses FC-72 (εr = 1.75) as the working fluid. Time-averaged film thicknesses measured using the capacitance sensor are compared against ensemble-averaged measurements using the CCD camera for annular vertical upflow and downflow. The upflow and downflow standard deviations are 0.17 and 0.093 mm, respectively. As expected, the agreement for vertical flow is not as good as that for the horizontal no-flow case, because large fluctuations in film thickness are characteristic of annular two-phase flow, and the uncertainty of the photographic measurement is increased.

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12

Vo, Hung T., and Frank G. Shi. "New Analytical Model for the Dielectric Loss of Microstrip Lines on Multilayer Dielectric Substrates: Effect of Conductor-Dielectric Interphase." Journal of Microelectronics and Electronic Packaging 3, no. 2 (April 1, 2006): 61–66. http://dx.doi.org/10.4071/1551-4897-3.2.61.

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The existing CAD formulae for dielectric loss of microstrip lines on substrate are complicated and inaccurate at high frequencies. In particular, no closed-form expression has been obtained for the dielectric loss of microstrip lines on multi-layer dielectric substrate by including the conductor-substrate interphase effect, although attempts have been made to study the finite thickness effect of the conductor and dielectric substrate. The present work represents the first attempt to obtain a closed-form CAD formula for the dielectric loss of microstrip lines on dielectric substrates by considering the effect of conductor-substrate interphase. Our simple and accurate model systematically considers the effect of the interphase between the microstrip line and substrate by using a quasi-TEM approach and is shown to be supported by the available experimental data.

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13

OSTED, ANDERS, JACOB KONGSTED, KURT MIKKELSEN, and OVE CHRISTIANSEN. "A CC2 dielectric continuum model and a CC2 molecular mechanics model." Molecular Physics 101, no. 13 (July 10, 2003): 2055–71. http://dx.doi.org/10.1080/0026897031000109338.

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14

Lucero, Jolie, James M. Crawford, Carla Osuna, and Moises A. Carreon. "Solvothermal synthesis of porous organic cage CC3 in the presence of dimethylformamide as solvent." CrystEngComm 21, no. 34 (2019): 5039–44. http://dx.doi.org/10.1039/c9ce00662a.

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15

Zhao, Jackson, Williams, and Oliner. "Simple CAD model for a dielectric leaky-wave antenna." IEEE Antennas and Wireless Propagation Letters 3 (2004): 243–45. http://dx.doi.org/10.1109/lawp.2004.837513.

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Li, Changzhi, and Kangsheng Chen. "Transmission Line Model Based CAD of Multilayer Dielectric Filters." International Journal of Infrared and Millimeter Waves 25, no. 5 (May 2004): 775–85. http://dx.doi.org/10.1023/b:ijim.0000027578.60002.28.

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Wiens, Alex, Christian Kohler, Matthias Hansli, Martin Schuessler, Matthias Jost, Holger Maune, Joachim R. Binder, and Rolf Jakoby. "CAD-assisted modeling of high dielectric contrast composite materials." Journal of the European Ceramic Society 37, no. 4 (April 2017): 1487–94. http://dx.doi.org/10.1016/j.jeurceramsoc.2016.10.032.

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Latha, C., and C. K. Mahadevan. "Growth and physicochemical characterization of calcium cadmium thiocyanate CaCd(SCN)4 single crystals." Materials Science-Poland 36, no. 4 (December 1, 2018): 704–10. http://dx.doi.org/10.2478/msp-2018-0093.

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AbstractIt is important to grow and characterize new bimetallic thiocyanate single crystals as they are expected to exhibit useful optical and electrical properties. In the present study, calcium cadmium thiocyanate CaCd(SCN)4 single crystals were grown by slow evaporation of solvent and were characterized chemically, structurally, thermally, optically and electrically. X-ray diffraction analysis indicates that the grown crystal belongs to the tetragonal crystal system with lattice parameters: a = b = 12.2491(7) Å and c = 15.1012(5) Å. EDAX spectral analysis confirms the expected chemical composition. Thermogravimetric (TG/DTA) measurement implies good thermal stability. Optical (UV-Vis-NIR absorption spectral and SHG efficiency) measurements suggest good optical absorption in the UV and blue regions and the SHG efficiency of 6.13 (in urea unit). The dielectric measurements carried out in the temperature range of 40 °C to 150 °C at five different frequencies, viz. 100 Hz, 1 kHz, 10 kHz, 100 kHz and 1 MHz indicate a normal dielectric behavior.

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Baillargear, D., S. Verdeyme, M. Aubourg, and P. Guillon. "CAD applying the finite-element method for dielectric-resonator filters." IEEE Transactions on Microwave Theory and Techniques 46, no. 1 (1998): 10–17. http://dx.doi.org/10.1109/22.654917.

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Liu, Qi Wen, Fei Chen, Qiang Shen, and Lian Meng Zhang. "Optimal Design for Ceramic Radomes with A-Sandwich Structure." Advanced Materials Research 66 (April 2009): 29–32. http://dx.doi.org/10.4028/www.scientific.net/amr.66.29.

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The radome performance is evaluated by means of a computer aided design (CAD) for the wall structure of multilayer ceramic radome in accordance with the microwave propagation theory. The calculation model for the ceramic radome with A-sandwich structure is built. By optimizing the thickness of the whole wall and the thickness and dielectric constant of skins and core layer, the power transmission efficiency at a broadband frequency of A-sandwich structure ceramic radome is calculated especially. The calculation results suggest that when the wall thickness is 6 mm, the thickness ratio of surface layer to core layer is 1:15 and dielectric constant of core layer is less than 2.5, the maximal broadband transmission efficiency is obtained.

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Mansoor Mahmood, Suhair, and Asaad M. Jassim Al-Hindawi. "Theoretical and Experimental Results of Substrate Effects on Microstrip Power Divider Designs." International Journal of Microwave Science and Technology 2011 (September 12, 2011): 1–9. http://dx.doi.org/10.1155/2011/980982.

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The effects of substrate materials on the design of microstrip power divider are investigated theoretically and experimentally. Three dielectric substrate materials, Duroid 3003, G10/FR4 epoxy Glass, and Duroid 3010, are chosen to be studied. A three-way two-stage power divider is designed at S-band frequency of 2.25 GHz and etched on each studied substrate separately. The substrate effects on the characteristics and performance of the microsrip circuits are studied taking into consideration the large difference in dielectric constant and the dissipation factor. The circuit designs presented here are analyzed using the Genesys CAD program and implemented and tested experimentally. The simulated and measured results are compared and discussed, and they indicate that significant changes in the characteristics of the microstrip power divider are observed.

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Weily, Andrew R., and Ananda S. Mohan. "Time-domain CAD of dual-mode HE11 dielectric resonator microwave filters." Microwave and Optical Technology Letters 29, no. 1 (2001): 6–11. http://dx.doi.org/10.1002/mop.1067.

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23

Zhu, Heng-Tian, Ye Chen, Yi-Feng Xiong, Fei Xu, and Yan-Qing Lu. "A Flexible Wireless Dielectric Sensor for Noninvasive Fluid Monitoring." Sensors 20, no. 1 (December 27, 2019): 174. http://dx.doi.org/10.3390/s20010174.

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A flexible wireless dielectric sensor is presented here for noninvasively monitoring the permittivity and conductivity of fluids, based on resistor–inductor–capacitor (RLC) resonant circuit and capacitively coupled contactless conductivity detection (C4D) technique. The RLC sensor consists of one single-turn inductor and one interdigital capacitor. The resonant frequency of the device is sensitive to the surrounding environment, thanks to the electric field leaked out between the interdigital capacitor electrodes. Through the high-frequency structure simulator (HFSS) simulation, and experiments on ethanol/water solutions and NaCl solutions, it was confirmed that a fluid’s permittivity and conductivity could be detected by the return loss curve (S11). With great repeatability and stability, the proposed sensor has potential for broad applications, especially in wearable low-cost smart devices.

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Bedra, S., R. Bedra, S. Benkouda, and T. Fortaki. "Efficient CAD Model to Analysis of High Tc Superconducting Circular Microstrip Antenna on Anisotropic Substrates." Advanced Electromagnetics 6, no. 2 (May 20, 2017): 40. http://dx.doi.org/10.7716/aem.v6i2.446.

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In this paper, an electromagnetic approach based on cavity model in conjunction with electromagnetic knowledge was developed. The cavity model combined with London’s equations and the Gorter-Casimir two-fluid model has been improved to investigate the resonant characteristics of high Tc superconducting circular microstrip patch in the case where the patch is printed on uniaxially anisotropic substrate materials. Merits of our extended model include low computational cost and mathematical simplify. The numerical simulation of this modeling shows excellent agreement with experimental results available in the literature. Finally, numerical results for the dielectric anisotropic substrates effects on the operating frequencies for the case of superconducting circular patch are also presented.

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25

Buliya, Asha, K. C. Pancholi, R. K. Paliwal, and S. P. Bhatnagar. "Dielectric Properties of Clay Loam Soil at Lower Microwave Frequencies." Solid State Phenomena 209 (November 2013): 229–32. http://dx.doi.org/10.4028/www.scientific.net/ssp.209.229.

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Real and Imaginary parts ( ) of the Complex Dielectric Permittivity (ε*) of Clay Loam soil collected from Nanta Farm, CAD, Kota, Rajasthan have been measured using a Vector Network Analyzer with varied Moisture contents and Salinity levels in the frequency range 150 MHz to 2.2 GHz. Both and are observed to be strongly dependent on moisture content. The Reflection coefficient(R) , Emissivity(e) and Brightness temperature(T_B) of Microwaves for the soil sample were also calculated from the measured permittivity data. These parameters have their own importance in remote sensing of soil moisture using Microwave signals and show expected variations with soil salinity and Microwave frequencies used.

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Tatham, A. S., M. N. Marsh, H. Wieser, and P. R. Shewry. "Conformational studies of peptides corresponding to the coeliac-activating regions of wheat α-gliadin." Biochemical Journal 270, no. 2 (September 1, 1990): 313–18. http://dx.doi.org/10.1042/bj2700313.

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The structures of four peptides corresponding to parts of the coeliac-activating protein A-gliadin were studied by structure prediction and c.d. spectroscopy. Three of the peptides corresponded to parts of the coeliac-activating N-terminal region (residues 3-55, 3-19 and 39-45) and contained two tetrapeptide motifs common to all coeliac-active regions (Pro-Ser-Gln-Gln and Gln-Gln-Gln-Pro). The Pro-Ser-Gln-Gln sequence was also present in the fourth peptide, on the basis of the C-terminal part of the molecule (211-217). These studies showed that beta-reverse turns were the predominant structural feature in all peptides and were predominantly of type I/III in two of the N-terminal peptides and type II in the C-terminal peptide. These turns form when the peptide is dissolved in solvents of low dielectric constant (trifluoroethanol) and high dielectric constant (water and iso-osmotic saline), although their presence in the N-terminal peptides may be masked in the latter solvents due to equilibrium with a poly-L-proline II structure favoured at lower temperatures.

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Vendik, Irina B., and Emil T. Kalendarov. "CAD model of effective dielectric constant of microstrip line on M-cut sapphire substrate." International Journal of Microwave and Millimeter-Wave Computer-Aided Engineering 5, no. 6 (November 1995): 402–5. http://dx.doi.org/10.1002/mmce.4570050606.

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García, Jesús, Jesús Rubio, Jose Ramón Montejo-Garai, and Juan Zapata. "CAD of cylindrical dielectric resonator filters by a 3-D finite-element segmentation method." Microwave and Optical Technology Letters 31, no. 1 (August 16, 2001): 71–75. http://dx.doi.org/10.1002/mop.1361.

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Galli, Alessandro, Davide Comite, Ilaria Catapano, Gianluca Gennarelli, Francesco Soldovieri, and Elena Pettinelli. "3D Imaging of Buried Dielectric Targets with a Tomographic Microwave Approach Applied to GPR Synthetic Data." International Journal of Antennas and Propagation 2013 (2013): 1–10. http://dx.doi.org/10.1155/2013/610389.

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Effective diagnostics with ground penetrating radar (GPR) is strongly dependent on the amount and quality of available data as well as on the efficiency of the adopted imaging procedure. In this frame, the aim of the present work is to investigate the capability of a typical GPR system placed at a ground interface to derive three-dimensional (3D) information on the features of buried dielectric targets (location, dimension, and shape). The scatterers can have size comparable to the resolution limits and can be placed in the shallow subsurface in the antenna near field. Referring to canonical multimonostatic configurations, the forward scattering problem is analyzed first, obtaining a variety of synthetic GPR traces and radargrams by means of a customized implementation of an electromagnetic CAD tool. By employing these numerical data, a full 3D frequency-domain microwave tomographic approach, specifically designed for the inversion problem at hand, is applied to tackle the imaging process. The method is tested here by considering various scatterers, with different shapes and dielectric contrasts. The selected tomographic results illustrate the aptitude of the proposed approach to recover the fundamental features of the targets even with critical GPR settings.

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Tatham, A. S., A. F. Drake, and P. R. Shewry. "Conformational studies of a synthetic peptide corresponding to the repeat motif of C hordein." Biochemical Journal 259, no. 2 (April 15, 1989): 471–76. http://dx.doi.org/10.1042/bj2590471.

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C hordein, a storage protein from barley grains, has an Mr of about 53,000, and consists predominantly of repeated octapeptides with a consensus sequence of Pro-Gln-Gln-Pro-Phe-Pro-Gln-Gln. Previously reported hydrodynamic and c.d. studies indicate the presence of beta-turns, the repetitive nature of which may lead to the formation of a loose spiral. In order to study these turns we have compared the structures of a synthetic peptide corresponding to the consensus repeat motif and total C hordein by using c.d. and Fourier-transform i.r. spectroscopy. The synthetic peptide exhibited spectra typical of beta I/III reverse turns when dissolved in trifluoroethanol at 22 degrees C and in water at 70 degrees C, but ‘random-coil’-like spectra in water at 22 degrees C. The whole protein also showed increases in beta I/III reverse turns when dissolved in increasing concentrations of trifluoroethanol (50-100%, v/v) or heated in ethanol/water (7:3, v/v). Two cryogenic solvent systems were used to determine the c.d. spectra of the peptide and protein at temperatures down to -100 degrees C. Methanol/glycerol (9:1, v/v) and ethanediol/water (2:1, v/v) were selected as analogues of trifluoroethanol/water and water respectively. The peptide exhibited beta I/III-reverse-turn and ‘random-coil’-like spectra in methanol/glycerol and ethanediol/water respectively at 22 degrees C, but a spectrum similar to that of a poly-L-proline II helix in both solvents at -100 degrees C. Similarly the proportion of this spectral type also increased when the whole protein was cooled in both solvents. These results indicate that a poly-L-proline II conformation at low temperatures is in equilibrium with a beta I/III-turn-rich conformation at higher temperatures. The latter conformation is also favoured in solvents of low dielectric constant such as trifluoroethanol. The ‘random-coil‘-like spectra exhibited by the protein and peptide in high-dielectric-constant solvents at room temperature may result from a mixture of the two conformations rather than from the random-coil state.

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Гусейналиев, М. Г., С. Н. Ясинова, Д. Н. Джалилли, and С. И. Мехтиева. "Оптические свойства и критические точки наноструктурированных тонких пленок PbSe." Физика и техника полупроводников 54, no. 6 (2020): 527. http://dx.doi.org/10.21883/ftp.2020.06.49379.9362.

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Spectroscopic ellipsometry (SE) method has been used to investigate the optical properties of nanostructured PbSe thin films obtained by chemıcal bath deposıtıon (CBD) method. For a better resolution of the structure of interband transitions and for determination of critical points, the function obtained by numerical differentiation of the experimental data of the dielectric function is used. The theoretical fitting was carried out using the "Graphical Analysis" program. The best fit ıs obtained with a 2D-critical point line shape (m = 0) for E=2÷3 eV energy region. One critical point corresponding to Eg = 2,5 eV have been determined. This value is attributed to the L4L6 transition of the Brillouin zone.

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Khan, Sidra, Nudrat Humera, Saba Niaz, Saira Riaz, Shahid Atiq, and Shahzad Naseem. "Simultaneous normal – Anomalous dielectric dispersion and room temperature ferroelectricity in CBD perovskite BaTiO3 thin films." Journal of Materials Research and Technology 9, no. 5 (September 2020): 11439–52. http://dx.doi.org/10.1016/j.jmrt.2020.08.009.

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Brun, Grégoire Le, Margo Hauwaert, Audrey Leprince, Karine Glinel, Jacques Mahillon, and Jean-Pierre Raskin. "Electrochemical Characterization of Nitrocellulose Membranes towards Bacterial Detection in Water." Proceedings 60, no. 1 (November 2, 2020): 61. http://dx.doi.org/10.3390/iecb2020-07080.

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Paper substrates have shown a high potential for development of cost-effective and efficient point-of-care biosensors, essential for public healthcare and environmental diagnostics. Most paper-based biosensors rely on qualitative colorimetric detection schemes with high limits of detection. To overcome this limitation, technologies that combine paper-based substrates and electrochemical detection are being developed to allow for quantification and achieve better performances. In this work, we explore the potential of dielectric measurements towards electrical detection of whole-cell bacteria in nitrocellulose membranes, a paper-derivative. Impedance spectroscopy was considered to characterize the membranes with and without Bacillus thuringiensis cells, used as model microorganism. To specifically target this bacterial strain, phage endolysin cell-wall binding domain (CBD) encoded by a bacteriophage targeting B. thuringiensis were prepared and integrated into the membranes as recognition biointerface. The fluid sample containing the bacteria is conducted in the membrane through passive capillarity, and the bacteria are specifically immobilized in the test zone. Resulting changes of the dielectric properties of the membrane are sensed through impedance changes, highlighting the contribution of ions in the bacterial detection mechanism. This experimental proof-of-concept illustrates the electrical detection of 108 CFU/mL bacteria in low-salinity buffers within 5 min.

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Zhang, Zuoqun, Chaoshan Yang, Hua Cheng, Longlong Zhou, Junru Ren, and Yuhao Zhu. "The Electromagnetic Wave Absorbing Property of Dual-Layer Cement Matrix Composites Based on the Principle of Electromagnetic Energy - Thermal Energy Conversion." International Journal of Heat and Technology 39, no. 6 (December 31, 2021): 2006–12. http://dx.doi.org/10.18280/ijht.390640.

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Based on the application of stealth technology in actual engineering projects, and according to the theory that when electromagnetic waves (EMW) pass through different wave absorbing materials, they will undergo resistance loss, dielectric loss, and magnetic loss, and the electromagnetic energy will be converted into thermal energy, this paper designed and developed a dual-layer EMW-absorbing Cement Matrix Composites (CMC) combining with the principle of impedance matching, and proposed to take cement paste mixed with expanded perlite as the matching layer of the newly developed material, and aggregate and nanomaterials as its wave absorbing layer. The aggregate was prepared by mixing 15wt.% 38μm Fe3O4 powder and 10wt.% 500nm SiC powder into the clay powder to produce cement raw pellets and calcine them at 1190℃, the fabricated aggregate has obvious dielectric loss and magnetic loss to EMW, and its crushing resistance strength can reach 13.7MPa. For the dual-layer test pieces made of the prepared aggregate and 2wt.% Conductive Carbon Black (CCB), within 8-18GHz frequency band, the bandwidth with a reflectivity lower than -10db reached 9.5GHz, the bandwidth with a reflectivity lower than -12db reached 7.55 GHz, and its maximum reflection loss reached -19.56db. In addition, the prepared CMC exhibited good mechanical properties, and its compressive strength reached 50.7MPa at the age of 28d.

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Das, M. R., A. Mukherjee, and P. Mitra. "Structural, optical and electrical characterization of CBD synthesized CdO thin films: influence of deposition time." Materials Science-Poland 35, no. 3 (October 20, 2017): 470–78. http://dx.doi.org/10.1515/msp-2017-0063.

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AbstractCadmium oxide (CdO) thin films were grown on glass substrates by chemical bath deposition (CBD) method for different deposition times using cadmium acetate as cationic precursor. The structural and optical characterization was carried out using XRD, TEM, and UV-Vis spectrophotometer measurements. Structural analyses with XRD confirmed cubic structure of the CdO. Average particle size estimated from Rietveld refinement method of XRD pattern corresponded well with TEM measurement. The optical band gap varied between 2.35 eV to 2.48 eV with deposition time and an increase in optical band gap with decreasing film thickness was observed. The AC electrical conduction behavior of the CdO film was investigated as a function of temperature as well as frequency. The conductivity measurements indicated localized conduction and hopping of carriers between localized states. The value of real part of dielectric constant was found to decrease with frequency and increase with temperature. The Nyquist plots at different temperatures showed the existence of both grains and grain boundaries contributing to conduction mechanism.

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Urbanowicz, Tomasz, Michał Michalak, Ewa Marzec, Anna Komosa, Krzysztof J. Filipiak, Anna Olasińska-Wiśniewska, Anna Witkowska, Michał Rodzki, Andrzej Tykarski, and Marek Jemielity. "Coronary Artery Disease and Inflammatory Activation Interfere with Peripheral Tissue Electrical Impedance Spectroscopy Characteristics—Initial Report." International Journal of Environmental Research and Public Health 20, no. 3 (February 3, 2023): 2745. http://dx.doi.org/10.3390/ijerph20032745.

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Background: The electrical properties of cells and tissues in relation to energy exposure have been investigated, presenting their resistance and capacitance characteristics. The dielectric response to radiofrequency fields exhibits polarization heterogeneity under pathological conditions. The aim of the study was to analyze the differences in changes in resistance and capacitance measurements in the range from 1 kHz to 1 MHz, combined with an assessment of the correlation between the results of electrical impedance spectroscopy (EIS) and inflammatory activation. Methods: In the prospective study, EIS was performed on the non-dominant arm in 29 male patients (median (Q1–Q3) age of 69 (65–72)) with complex coronary artery disease and 10 male patients (median (Q1–Q3) age of 66 (62–69)) of the control group. Blood samples were collected for inflammatory index analysis. Results: The logistic regression analysis revealed a negative correlation with inflammatory indexes, including neutrophil to lymphocyte ratio (NLR) in the CAD group in the frequency of 30 kHz (p = 0.038, r = −0.317) regarding EIS resistance measurements and a positive correlation in CAD group in the frequency of 10 kHz (p = 0.029, r = −0.354) regarding EIS capacitance. Conclusions: The bioelectric characteristics of peripheral tissues measured by resistance and capacitance in EIS differ in patients with coronary artery disease and in the control group. Electrical impedance spectroscopy reveals a statistically significant correlation with inflammatory markers in patients with CAD.

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TEZEL, FATMA MEYDANERİ, OSMAN ÖZDEMİR, and İ. AFŞIN KARİPER. "THE EFFECTS OF pH ON STRUCTURAL AND OPTICAL CHARACTERIZATION OF IRON OXIDE THIN FILMS." Surface Review and Letters 24, no. 04 (August 29, 2016): 1750051. http://dx.doi.org/10.1142/s0218625x17500512.

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In this study, the iron oxide thin films have been produced by chemical bath deposition (CBD) method as a function of pH onto amorphous glass substrates. The surface images of the films were investigated with scanning electron microscope (SEM). The crystal structures, orientation of crystallization, crystallite sizes, and dislocation density i.e. structural properties of the thin films were analyzed with X-ray diffraction (XRD). The optical band gap ([Formula: see text], optical transmission ([Formula: see text]%), reflectivity ([Formula: see text]%), absorption coefficient ([Formula: see text], refraction index ([Formula: see text]), extinction coefficient ([Formula: see text]) and dielectric constant ([Formula: see text]) of the thin films were investigated depending on pH, deposition time, solution temperature, substrate temperature, thickness of the films by UV–VIS spectrometer.

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Tezel, Fatma Meydanerİ, and İ. Afşin Kariper. "Synthesis, surface tension, optical and dielectric properties of bismuth oxide thin film." Materials Science-Poland 35, no. 1 (March 10, 2017): 87–93. http://dx.doi.org/10.1515/msp-2017-0020.

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AbstractBismuth oxide thin film was deposited by chemical bath deposition (CBD) technique onto a glass substrate. The grain size (D), dislocation density (δ) and number of crystallites per unit area (N), i.e. structural properties of the thin film were determined as 16 nm, 39.06× 10–4line/nm2, 31.25 × 10–31/nm2, respectively. Optical transmittance properties of the thin film were investigated by using a UV-Vis spectrophotometer. The optical band gap (Eg) for direct transitions, optical transmission (T %), reflectivity (R %), absorption, refractive index (nr), extinction coefficient (k), dielectric constant (∊) of the thin film were found to be 3.77 eV, 25.23 %, 32.25 %, 0.59, 3.62, 0.04 and 2.80, respectively. The thickness of the film was measured by AFM, and was found to be 128 nm. Contact angles of various liquids on the oxide thin film were determined by Zisman method, and surface tension was calculated to be 31.95 mN/m.

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SUGANTHI, S., K. MURUGESAN, and S. RAGHAVAN. "OPTIMIZED MECHANICAL DESIGN OF CAPACITIVE MICROMACHINED SWITCH: A CAD-BASED NEURAL MODEL." Journal of Circuits, Systems and Computers 23, no. 03 (March 2014): 1450037. http://dx.doi.org/10.1142/s0218126614500376.

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In this paper, the authors propose the neural modeling of optimized design for pull-in instability reduction of micromachined capacitive shunt radio frequency (RF) micro electro mechanical system (MEMS) switch. Prediction of effective dielectric constant and hence the critical collapse voltage that represents the bridge position instability for two typical bridge geometrics have been derived using artificial neural network (ANN). The effects of residual stress, length of center conductor and the gap between the bridge and center conductor of switch in lowering the driving voltage have been studied. Based on the neural model results, we have observed the reduction of 3 V in critical collapse voltage for an increase of 10 μm in length of center conductor. We have also noted the strong variation in voltage (reduction of 0.8 V for 1 MPa residual stress reduction) with respect to residual stress change. We achieved the reduction of 1.5 V in collapse voltage by reducing the gap between the bridge and the center conductor by 0.1 μm. Among the two structures considered, the structure with lower width of the center conductor proved as an optimum in achieving low critical collapse voltage. Further, the performance of trained neural network with the training datasets derived from MATLAB simulation has been evaluated in terms of convergence speed and mean square error.

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Gilb, J. P. K., and C. A. Balanis. "Accurate and efficient computation of dielectric losses in multi-level, multi-conductor microstrip for CAD applications." IEEE Transactions on Microwave Theory and Techniques 41, no. 3 (March 1993): 527–30. http://dx.doi.org/10.1109/22.223757.

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Govindasamy, Geetha, Kaushik Pal, M. Abd Elkodous, Gharieb S. El-Sayyad, Kumar Gautam, and Priya Murugasan. "Growth dynamics of CBD-assisted CuS nanostructured thin-film: optical, dielectric and novel switchable device applications." Journal of Materials Science: Materials in Electronics 30, no. 17 (August 26, 2019): 16463–77. http://dx.doi.org/10.1007/s10854-019-02022-4.

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Delrue, R., C. Seguinot, P. Pribetich, and P. Kennis. "Desktop computer models for cad of coplanar lines laid on semiconductor layers with dielectric cap layer." Microwave and Optical Technology Letters 2, no. 5 (May 1989): 183–88. http://dx.doi.org/10.1002/mop.4650020512.

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Kirihara, Soshu. "Stereolithographic Additive Manufacturing of Bulky Ceramic Components with Functionally Geometric Micropattern." Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2016, CICMT (May 1, 2016): 000001–5. http://dx.doi.org/10.4071/2016cicmt-ta11.

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Abstract In a stereolithographic additive manufacturing (AM), two dimensional (2D) cross sectional patterns were created through photo polymerization by ultraviolet laser drawing on spread resin paste including ceramic nanoparticles, and three dimensional (3D) composite models were sterically printed by layer lamination through chemical bonding. An automatic collimeter was equipped with the laser scanner to adjust beam diameter. Fine or coarse beams could realize high resolution or wide area drawings, respectively. Metal and ceramic bulky components including dendritic networks were geometrically built by using stereolithographic AM. Geometric patterns with periodic, self-similar, graded and fluctuated arrangements were created by computer aided design, manufacture and evaluation (CAD/CAM/CAE) for effective modulations of energy and material flows through dielectric lattices in photonic crystals, porous electrodes in fuel cells and biological scaffolds in artificial bones.

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Tezel, Fatma Meydaneri, and İ. Afşin Kariper. "Effect of pH on the structural and optical properties of polycrystalline ZnSe thin films produced by CBD method." International Journal of Modern Physics B 33, no. 05 (February 20, 2019): 1950024. http://dx.doi.org/10.1142/s0217979219500243.

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In this study, zinc selenide (ZnSe) thin films were produced on glass substrate by using chemical bath deposition (CBD) method at 80[Formula: see text]C, from aqueous solutions of zinc sulphate and sodium selenosulphide, which were produced using solid selenium as the selenium source. The optical and structural properties of ZnSe thin films were investigated at room-temperature. The pH of the chemical bath, in which ZnSe thin films were immersed, were changed between pH:8–11. Optical properties of the films, including extinction coefficient, refractive index, reflectance, absorbance, transmittance, dielectric constants and optical density values were calculated using absorbance and transmittance measurements determined using a Hach Lange 500 spectrophotometer, in 300–1100 nm wavelength range. Optical bandgap values were obtained from transmittance and absorbance spectra ranged between 2.12 and 2.49 eV. According to XRD results, it was found that the films have polycrystalline structure and they exhibited different film thicknesses depending on phase and pH changes.

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Moon, Ethan M., and Vadim V. Yakovlev. "Computer-aided design of a dielectric insert supporting uniformity of fast microwave heating." COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 37, no. 6 (November 5, 2018): 1958–68. http://dx.doi.org/10.1108/compel-06-2017-0266.

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PurposeThis paper aims to introduce and illustrate a computational technique capable of determining the geometry and complex permittivity of a supplementary dielectric insert making distributions of microwave-induced dissipated power within the processed material as uniform as possible.Design/methodology/approachThe proposed technique is based on a 3D electromagnetic model of the cavity containing both the processed material and the insert. Optimization problem is formulated for design variables (geometrical and material parameters of the insert) identified from computational tests and an objective function (the relative standard deviation [RSD]) introduced as a metric of the field uniformity. Numerical inversion is performed with the method of sequential quadratic programming.FindingsFunctionality of the procedure is illustrated by synthesis of a dielectric insert in an applicator for microwave fixation. Optimization is completed for four design variables (two geometrical parameters, dielectric constant and the loss factor of the insert) with 1,000 points in the database. The best three optimal solutions provide RSD approximately 20 per cent, whereas for the patterns corresponding to all 1,000 non-optimized (randomly chosen) sets of design variables this metric is in the interval from 27 to 136 per cent with the average of 78 per cent.Research limitations/implicationsAs microwave thermal processing is intrinsically inhomogeneous and the heating time is not a part of the underlying model, the procedure is able to lead only to a certain degree of closeness to uniformity and is intended for applications with high heating rates. The initial phase of computational identification of design variables and their bounds is therefore very important and may pre-condition the “quality” of the optimal solution. The technique may work more efficiently in combination with advanced optimization techniques dealing with “smart” (rather than random) generation of the data; for the use with more general microwave heating processes characterized by lower heating rates, the technique has to use the metric of non-uniformity involving temperature and heating time.Practical implicationsWhile the procedure can be used for computer-aided design (CAD) of microwave applicators, a related practical limitation may emerge from the fact that the material with particular complex permittivity (determined in the course of optimization) may not exist. In such cases, the procedure can be rerun for the constant values of material parameters of the available medium mostly close to the optimal ones to tune geometrical parameters of the insert. Special manufacturing techniques capable of producing a material with required complex permittivity also may be a practical option here.Originality/valueNon-uniformity of microwave heating remains a key challenge in the design of many practical applicators. This paper suggests a concept of a practical CAD and outlines corresponding computational procedure that could be used for designing a range of applied systems with high heating rates.

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Das, Mahima Ranjan, and Partha Mitra. "Influence of Mn incorporation on ionic conductivity and dielectric relaxation process in CBD synthesized CdO thin films." Journal of Alloys and Compounds 724 (November 2017): 614–24. http://dx.doi.org/10.1016/j.jallcom.2017.07.073.

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Mahdi, Najib, Stephane Bila, Serge Verdeyme, Michel Aubourg, Khaled Khoder, Annie Bessaudou, Françoise Cosset, et al. "A shape optimization library for the design of microwave components." International Journal of Microwave and Wireless Technologies 6, no. 1 (November 18, 2013): 31–37. http://dx.doi.org/10.1017/s1759078713000950.

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This paper outlines an original shape optimization library backed by a three dimensional (3D) full-wave electromagnetic (EM) simulator, combining several efficient structural optimization techniques and suitable for viable computer-aided design (CAD) of complex microwave components. The microwave components are modeled by finite element method (FEM) and their dimensions and shape are optimized using four techniques: design of experiments (DOE), level-set method (LS), topology gradient (TG) method, and genetic algorithm (GA). The various methods allow determining the optimal geometry, shape or topology of 2D or 3D objects within the microwave device, by minimizing iteratively a cost function related to the desired specifications. Typical demonstration illustrates the versatility of the proposed library based on the design of a dual mode dielectric resonator filter in order to improve its unloaded quality factor by keeping the same frequency isolation, their accuracy and efficiency are verified by the available measured results.

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Das, M. R., A. Mukherjee, and P. Mitra. "Influence of Cu incorporation on ionic conductivity and dielectric relaxation mechanism in NiO thin films synthesized by CBD." Journal of Materials Science: Materials in Electronics 29, no. 2 (October 16, 2017): 1216–31. http://dx.doi.org/10.1007/s10854-017-8024-x.

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TAI, K. L. "SI-ON-SI MCM TECHNOLOGY AND ITS APPLICATIONS." International Journal of High Speed Electronics and Systems 02, no. 04 (December 1991): 251–61. http://dx.doi.org/10.1142/s0129156491000120.

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Multichip Module (MCM) packaging has been used in high-end systems, such as mainframe and supercomputers for some time. Rapid advances in VLSI technology and novel system architecture concepts have presented both challenges and opportunities for MCM technologists. We should not just try to find a solution, but also try to take a long-term view and plan the technological development. We would like to develop MCM technology which has a broad range of applications from consumer products to supercomputers. The technology should focus on low cost, high performance, compact size, and high reliability. We believe that it is most attractive to leverage IC technology and surface mount technology (SMT). Therefore we select Si wafer as the substrate, Al as the metallization, polyimide as the dielectrics, Ta-Si as the resistor material, and Si oxide and nitride as the dielectrics for capacitor. Flip-chip solder attachment are used to assemble chips on the substrate. We view our version of MCM as a “giant chip” rather than a miniaturized printed wiring board. This “giant chip” contains mixed device technologies which cannot be obtained by current device technology. The migration path should be from small to large module. The infrastructure of the CAD system and the testing system is critical for the development of MCM technology. Potential applications and implementations of MCM technology are given in this paper.

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Myles, David, David Milne, and Jonathan D. Shephard. "Scanned Mask Imaging Ablative DPSS UV Laser Process for 2μm L/S RDL." Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2015, DPC (January 1, 2015): 000554–89. http://dx.doi.org/10.4071/2015dpc-tp21.

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Laser embedding conductors within a dielectric offers numerous advantages in fabricating redistribution layers (RDLs) for chip packages. Ablation of features down to 2μm L/S gives more routing space per layer and addresses the technology gap between semiconductor and PCB technologies. Microvias are made in the same process step as the circuitry, facilitating near padless vias further increasing the routing space available per layer. For a given package, this reduces the layer count and conductor path length required reducing the height profile of the package and improving signal integrity. Embedding the conductor can also improve its adhesion to the substrate and improve the co-planarity of subsequent layers in the build up. It also removes the need for the wet photochemistry associated with lithographic techniques. This presentation analyses the results of a novel UV, diode pumped solid state (DPSS), ablative mask imaging laser system for cost effective, high volume, 3D structuring of organic dielectrics. Two methods are widely used to micro-structure materials by laser: mask projection and direct write. Excimer lasers are typically used in mask projection systems, where their high pulse energy and low coherence make them well suited to imaging. These systems can achieve the required ablation quality with 2–3μm line width and space, however excimer lasers have a high capital cost and require regular and costly maintenance when compared with DPSS lasers. The high beam quality and lower pulse energy of DPSS lasers makes them better suited to a direct write approach. A galvanometer scan head used in conjunction with an f-theta scan lens can be used to scan a focused beam across a substrate. Since the pattern is defined by a CAD file, these systems are very flexible and thus appropriate for low volume prototyping. However, complicated control systems are required to accurately control the ablated depth, and constraints in the circuit design are imposed by the direct write approach. Also, because each feature is marked sequentially, the process time is proportional to the pattern complexity, which makes these tools prohibitively slow for high volume manufacture of the high density RDLs required in the next generation of device packages. This presentation outlines a scanned mask imaging system, wherein a low maintenance, cost efficient, frequency tripled, nanosecond, multimode UV solid state laser is used to illuminate a binary reticle. The multimode beam has an approximately Gaussian beam profile which is homogenised to form a square, flat top profile. A galvanometer scan head is used to raster scan the binary reticle. The reticle is subsequently imaged onto the substrate by a projection lens. Ablation of various features down to 2μm L/S in a variety of low K organic dielectrics is demonstrated. Accurate registration of pads with vias down to 5μm diameter highlights the feasibility of the process for high density RDLs and micro-vias for organic interposers. The process can achieve an ablation quality comparable to that of an excimer laser system, but with the advantage of significant cost saving and ease of maintenance in an industrial environment.

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Journal articles on the topic 'Dielectric CCD'

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