Статті в журналах: "Dielectric penetration"

1

Tıraş, Buşra, Sercan Dede, and Filiz Altay. "Dielectric Properties of Foods." Turkish Journal of Agriculture - Food Science and Technology 7, no. 11 (November 22, 2019): 1805. http://dx.doi.org/10.24925/turjaf.v7i11.1805-1816.2650.

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Dielectric properties of materials are used for evaluating their interactions with electromagnetic energy. Dielectric properties of food materials are required for various applications in food industry such as microwave (at 915 or 2450 MHz), radio wave (at 13.56, 27.12 or 40.68 MHz) and magnetic field processing. In order to understand the response of food materials to electromagnetic energy, dielectric parameters must be determined as a function of frequency, temperature, composition and moisture content. In this review, the dielectric properties of different food groups were listed depending on temperature and frequency ranges. In addition to the literature data of dielectric properties, the penetration depths of microwave or radio wave through food groups were calculated. The effects of temperature and composition (mostly moisture content) on dielectric properties depend on the type of the food and sometimes on frequency. However, the effect of frequency is constant; increased frequency decreased dielectric constant, loss factor and penetration depth. The lowest calculated penetration depth belonged to the fish surimi gel as 3.39 mm at microwave frequency whereas they were high generally for fats, oily seeds and flours (max was 372602 mm for corn flour). It appears that dielectric properties of foods should be investigated further depending on the interactions between frequency, temperature and composition. And then, dielectric heating based on the aim of the process can be applied accordingly. Besides, it appears that the moisture content and especially the dipole rotation and the conductivity movements of the molecules in free water content of the food are some of the most critical factors influencing the dielectric properties of food materials.

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Singh, A., G. K. Meena, S. Kumar, and K. Gaurav. "ANALYSIS OF THE EFFECT OF INCIDENCE ANGLE AND MOISTURE CONTENT ON THE PENETRATION DEPTH OF L- AND S-BAND SAR SIGNALS INTO THE GROUND SURFACE." ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences IV-5 (November 15, 2018): 197–202. http://dx.doi.org/10.5194/isprs-annals-iv-5-197-2018.

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Abstract. We study the functional relationship between the dielectric constant of soil-water mixture and penetration depth of microwave signals into the ground at different frequency (L&amp;S) band and incidence angles. Penetration depth of microwave signals into the ground depends on the incidence angle and wavelength of radar pulses and also on the soil properties such as moisture content and textural composition. It has been observed that the longer wavelengths have higher penetration in the soil but the penetration capability decreases with increasing dielectric behaviour of the soil. Moisture content in the soil can significantly increase its dielectric constant. Various empirical models have been proposed that evaluate the dielectric behaviour of soil-water mixture as a function of moisture content and texture of the soil. In this analysis we have used two such empirical models, the Dobson model and the Hallikainen model, to calculate the penetration depth at L- and C-band in soil and compared their results. We found that both of these models give different penetration depth and show different sensitivity towards the soil composition. Hallikainen model is more sensitive to soil composition as compared to Dobson model. Finally, we explore the penetration depth at different incidence angle for the proposed L- and S-band sensor of upcoming NASA-ISRO Synthetic Aperture Radar (NISAR) mission by using Hallikainen empirical model. We found that the soil penetration depth of SAR signals into the ground decreases with the increase in soil moisture content, incident angle and frequency.

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3

Chipman, Daniel M. "Charge penetration in dielectric models of solvation." Journal of Chemical Physics 106, no. 24 (June 22, 1997): 10194–206. http://dx.doi.org/10.1063/1.474048.

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4

YU Zhenfang, 余振芳, 马凤英 MA Fengying, 苏建坡 SU Jianpo, 陈明 CHEN Ming, and 池泉 CHI Quan. "Penetration Depth Calculation of Quarterwave Dielectric Mirrors." ACTA PHOTONICA SINICA 39, no. 11 (2010): 1967–70. http://dx.doi.org/10.3788/gzxb20103911.1967.

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5

Kamaruddin, Mohd Johari, Muhammad Abbas Ahmad Zaini, Anwar Johari та Tuan Amran Tuan Abdullah. "Dielectric Properties for the Ring Opening Polymerisation of ε-Caprolactone". Applied Mechanics and Materials 493 (січень 2014): 621–27. http://dx.doi.org/10.4028/www.scientific.net/amm.493.621.

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A dielectric property study was performed across a wide range of frequencies and temperatures onring opening polymerisation of ε-caprolactone system in order to relate quantitatively their dielectric properties to microwave heating mechanisms. An analysis of the results concluded that heating mechanism of the polymerisation mixtures in a microwave field was controlled by the dielectric properties of monomer, where the monomer was the major component (>90 % volume/volume) as well as the component with highest dielectric loss and dissipation factor. The penetration depth of mixtures at 2.45 GHz was noted to increase from ~0.58 cm (at 20 C) to ~3.3 cm (at 150 °C). This small penetration depth limits the potential to achieve the successful scale up of a microwave-assisted polymerisation of ε-caprolactone in batch mode at 2.45 GHz. As a result, this will lead to inhomogeneous bulk temperature distribution within the polymerisation mixture and irreproducible chemistry. However, a fast heating rate based on a high value of dissipation factor and dielectric loss of the polymerisation mixtures shows potential to enable the reaction to be completed in a few seconds that may allow the polymerisation to be transferred to a continuous flow process. In so doing, small diameter tubular reactors can be employed hence removing this penetration depth issue. Thus, the polymerisation mixtures dielectric properties are worth to be considered to ensure the reliability and reproducibility of the microwave assisted synthesis of poly-ε-caprolactone at large scale production.

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6

Liu, Chenhui, Libo Zhang, Jinhui Peng, Wenwen Qu, Bingguo Liu, Hongying Xia, and Junwen Zhou. "Dielectric Properties and Microwave Heating Characteristics of Sodium Chloride at 2.45 GHz." High Temperature Materials and Processes 32, no. 6 (December 1, 2013): 587–96. http://dx.doi.org/10.1515/htmp-2013-0008.

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AbstractThe effects of moisture content and temperature on the dielectric property of sodium chloride were investigated by using open-ended senor dielectric measurement system at the frequency of 2.45 GHz. Moisture content is a major influencing factor in the variation of dielectric properties. Dielectric constant, loss factor and loss tangent all increase linearly with moisture content increasing. Three predictive models were developed to obtain dielectric constant, loss factor, loss tangent and of sodium chloride as linear functions of moisture content. Temperature between 20 °C and 100 °C has a positive effect on dielectric constant and loss factor. Penetration depth decreased nonlinearly with moisture and temperature increasing. A predictive model was developed to calculate penetration depth for sodium chloride as a fifth function of moisture content. In addition, the measurements indicate that the particles temperature increases linearly with microwaving heating time at different power levels. The knowledge gained from these results is useful in developing more effective applications of microwave drying and designing better sensors for measuring moisture content of sodium chloride.

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Beh, Chong You, Ee Meng Cheng, Nashrul Fazli Mohd Nasir, Mohd Shukry Abdul Majid, Shing Fhan Khor, Mohd Ridzuan Mohd Jamir, Emma Ziezie Mohd Tarmizi, and Kim Yee Lee. "Regression Analysis of the Dielectric and Morphological Properties for Porous Nanohydroxyapatite/Starch Composites: A Correlative Study." International Journal of Molecular Sciences 23, no. 10 (May 19, 2022): 5695. http://dx.doi.org/10.3390/ijms23105695.

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This paper aims to investigate the dielectric properties, i.e., dielectric constant (ε′), dielectric loss factor (ε″), dielectric tangent loss (tan δ), electrical conductivity (σ), and penetration depth (Dp), of the porous nanohydroxyapatite/starch composites in the function of starch proportion, pore size, and porosity over a broad band frequency range of 5 MHz–12 GHz. The porous nanohydroxyapatite/starch composites were fabricated using different starch proportions ranging from 30 to 90 wt%. The results reveal that the dielectric properties and the microstructural features of the porous nanohydroxyapatite/starch composites can be enhanced by the increment in the starch proportion. Nevertheless, the composite with 80 wt% of starch proportion exhibit low dielectric properties (ε′, ε″, tan δ, and σ) and a high penetration depth because of its highly interconnected porous microstructures. The dielectric properties of the porous nanohydroxyapatite/starch composites are highly dependent on starch proportion, average pore size, and porosity. The regression models are developed to express the dielectric properties of the porous nanohydroxyapatite/starch composites (R2 > 0.96) in the function of starch proportion, pore size, and porosity from 1 to 11 GHz. This dielectric study can facilitate the assessment of bone scaffold design in bone tissue engineering applications.

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Liu, Boyan, Yu Lei, Shitao Sun, and Jie Zhang. "Thompson-Lampard Theorem for Dielectric Characteristics Detection of Generator Stator Insulation." Journal of Physics: Conference Series 2246, no. 1 (April 1, 2022): 012039. http://dx.doi.org/10.1088/1742-6596/2246/1/012039.

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Abstract The insulation of large generator stator winding will be gradually aging in the long-term operation process. The traditional aging test method cannot accurately locate the non-penetrating local defects of winding. Interdigital electrode is widely used in the fields of environmental monitoring and food detection because of its excellent characteristics such as self-closing and unidirectional penetration, but it has not been popularized in the identification of generator insulation aging. The paper proposes an interdigital electrode structure based on the Thompson-Lampard theory. The electrode suitable for dielectric characteristic detection of stator winding, and the electrode structure is optimized by using the finite element method from the parameters of signal strength, sensitivity and penetration depth. With the help of optimising, the measuring accuracy of the electrode can reach 0.1 level. Then, the different moisture conditions of water-cooled generator and air-cooled generator are simulated to verify the feasibility that interdigital electrode can detect insulation moisture which is an important factor in accelerating insulation aging. Finally, the moisture depth detection results show that the electrode combination based on the Thompson-Lampard theory can be used to locate moisture depth accurately, it is of great significance for the prevention of insulation aging and the pre-diagnosis.

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Josh, Matthew, Melvyn J. Lintern, Anton W. Kepic, and Mike Verrall. "Impact of grain-coating iron minerals on dielectric response of quartz sand and implications for ground-penetrating radar." GEOPHYSICS 76, no. 5 (September 2011): J27—J34. http://dx.doi.org/10.1190/geo2010-0321.1.

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An unexpected result of ground-penetrating radar (GPR) surveys in the Great Victoria Desert (South Australia) was the lack of returning signal in what appeared to be a favorable environment for GPR, with dry silica sand and calcrete aggregates in the near surface. We found that the dielectric response of the dry sand samples had much higher dielectric losses than comparable sands from Western Australia and that the dielectric losses are controlled by the presence of iron oxide minerals, although iron concentrations themselves are only around 0.4%. The samples contained over 90% quartz, with subsidiary amounts of carbonates, kaolin, and smectite occurring with the iron oxide minerals as a coating on the quartz grains. An acid washing procedure removed the reducible iron oxide minerals from the clay coating but left the clays substantially unaltered. Subsequent dielectric and magnetic analysis of the samples indicates that the iron oxide minerals removed during the washing process are responsible for the reduction of GPR penetration at 250 MHz from approximately 10 m to only 1 m.

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Das, Aparna, Ram Naresh Yadav, and Bimal K. Banik. "Microwave-Induced Surface-Mediated Highly Efficient Regioselective Nitration of Aromatic Compounds: Effects of Penetration Depth." Asian Journal of Chemistry 33, no. 9 (2021): 2203–6. http://dx.doi.org/10.14233/ajchem.2021.23131.

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Surface mediated highly regioselective nitration of aromatic compounds under diverse microwaveinduced conditions was investigated in this work. The effects of the penetration depth of the surfaces were found to be more crucial than other dielectric parameters. Despite significant progress of microwave-induced reactions, no reports have examined the penetration depth of the surfaces used in these processes.

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11

Al-Wakeel, Haitham B., Zainal Ambri Abdul Karim, Hussain Hamoud Al-Kayiem, and Hasan Fawad. "Numerical Simulation of High Frequency Electromagnetic Wave in Microwave Cavity for Soot Oxidation." Applied Mechanics and Materials 459 (October 2013): 310–18. http://dx.doi.org/10.4028/www.scientific.net/amm.459.310.

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Soot oxidation temperature by high frequency electromagnetic energy was proposed using numerical simulation by combining electromagnetic with transient thermal analyses. Equation of electric field distribution in a microwave cavity with perfect electric conductor surfaces and TE10 mode is formulated from Helmholtz equation. The dissipated heat distribution is calculated from the electric field distribution. Six study cases for electric field and dissipated heat distributions were implemented by using ANSYS software based on finite element method. The impact of dielectric sample properties, position, size and shape inside the microwave cavity were predicted. The results from the simulation of electric field and dissipated heat were compared with available data in literature and showed the validity of the analysis. It was found that the electric field forming hot spots at penetration depth and front corners of the soot sample and penetration depth is equal to 12mm but equal to 0 for samples with dimensions less than penetration depth. Dissipated heat pattern depend on electric field pattern and dielectric properties.

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12

Barman, Jitesh, Wan Shao, Biao Tang, Dong Yuan, Jan Groenewold, and Guofu Zhou. "Wettability Manipulation by Interface-Localized Liquid Dielectrophoresis: Fundamentals and Applications." Micromachines 10, no. 5 (May 16, 2019): 329. http://dx.doi.org/10.3390/mi10050329.

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Electric field-based smart wetting manipulation is one of the extensively used techniques in modern surface science and engineering, especially in microfluidics and optofluidics applications. Liquid dielectrophoresis (LDEP) is a technique involving the manipulation of dielectric liquid motion via the polarization effect using a non-homogeneous electric field. The LDEP technique was mainly dedicated to the actuation of dielectric and aqueous liquids in microfluidics systems. Recently, a new concept called dielectrowetting was demonstrated by which the wettability of a dielectric liquid droplet can be reversibly manipulated via a highly localized LDEP force at the three-phase contact line of the droplet. Although dielectrowetting is principally very different from electrowetting on dielectrics (EWOD), it has the capability to spread a dielectric droplet into a thin liquid film with the application of sufficiently high voltage, overcoming the contact-angle saturation encountered in EWOD. The strength of dielectrowetting depends on the ratio of the penetration depth of the electric field inside the dielectric liquid and the difference between the dielectric constants of the liquid and its ambient medium. Since the introduction of the dielectrowetting technique, significant progress in the field encompassing various real-life applications was demonstrated in recent decades. In this paper, we review and discuss the governing forces and basic principles of LDEP, the mechanism of interface localization of LDEP for dielectrowetting, related phenomenon, and their recent applications, with an outlook on the future research.

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Wang, Gui Qiu, Si Yuan Liu, and Yao Chuan Wang. "Slowing down for Ion Penetration through Plasmas." Applied Mechanics and Materials 703 (December 2014): 94–97. http://dx.doi.org/10.4028/www.scientific.net/amm.703.94.

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Slowing down processes for a proton and a carbon ion penetration through plasmas are studied within the dielectric response theory.The results show that the stopping power of ion will increase in lower projectile velocity, while the value of stopping power will decrease for higer velocity, and there is a maximum value for stopping power for some projectile velocity due to the resonace of excitation of plasmas. In addition, the stopping power will have higher value for carbon ion than proton due to the effects of charge states. Introduction

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14

Volkhin, I. L., and N. N. Korotaev. "Light penetration through a single-row layer of dielectric particles." Technical Physics Letters 26, no. 7 (July 2000): 591–93. http://dx.doi.org/10.1134/1.1262922.

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Izzati Abd Karim, Nurul, Samira Albati Kamaruddin, and Rozaimi Che Hasan. "Performance of Soil Water Content Using Ground Penetrating Radar with Different Antenna Frequencies." International Journal of Engineering & Technology 7, no. 2.29 (May 22, 2018): 815. http://dx.doi.org/10.14419/ijet.v7i2.29.14263.

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Accurate measurements of Soil Water Content (SWC) with applicable and relevant support are essential in many fields of earth and soil engineering research. Ground Penetrating Radar (GPR) is a geophysical tool that measures and provides accurate results for determination of the SWC. To prove the accuracy of SWC measurement using GPR, a field survey was performed in peat soil. This paper presents a fieldwork survey with the aim of assessing the SWC measurement using GPR. The survey work was conducted at Johor Bharu using different antenna frequencies (250 and 700 MHz). Five profiles, which is 5m by 5m in length, were scanned along an east-west direction with a common offset at an equal spacing of 1m. To measure the SWC using GPR, the researchers used the velocity from the GPR’s signal from the receiving antenna to the soil. Statistical analysis was carried out based on the dielectric permittivity and SWC. Schaap’s equation and Roth’s equation were used to distinguish the relative dielectric permittivity of the soil to SWC. The results of this study show the linear function, for the measured SWC. The validation graph shows that at a frequency of 250 MHz, the depth of penetration was greater compared to the frequency of 750 MHz. These results, suggest that a higher frequency will give higher resolution but lower depth penetration.

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Carpenter, Chris. "Study Interprets Electromagnetic-Wave Penetration, Absorption for Bitumen Reservoir." Journal of Petroleum Technology 73, no. 01 (January 1, 2021): 48–49. http://dx.doi.org/10.2118/0121-0048-jpt.

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This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 199941, “Interpretation of Electromagnetic-Wave Penetration and Absorption for Different Reservoir Mineralogy - Quartz-Rich, Limestone-Rich, and Clay-Rich - and at High- and Low-Water Saturation Values for a Bitumen Reservoir,” by Matthew Morte, SPE, Hasan Alhafidh, SPE, and Berna Hascakir, SPE, Texas A&M University, prepared for the 2020 SPE Canada Heavy Oil Conference, originally scheduled to be held in Calgary, 18–19 March. The paper has not been peer reviewed. Interpretation of logging data generated through electromagnetic (EM) waves or determination of EM-wave propagation in a medium as an enhanced-oil-recovery (EOR) method are not easy tasks. The complete paper aims to identify the role of different geological settings with different types of fluid saturations in the response of EM-wave propagation and absorption. Several correlations were created in this study and can be used to better interpret the reservoir mineralogy and fluid saturation as a response to EM-wave logging. Moreover, these results can be used to estimate the effective area (penetration depth) of EM waves as an EOR method. Experimental Procedure Complex permittivity of synthesized rock samples was recorded by means of a vector network analyzer as the source and a dielectric probe kit as the transmitter. The dielectric probe behaves as both the transmitter and receiver simultaneously by measuring the proportion of the reflected wave. The dielectric probe is capable of measuring both the solid interface, as is the case with the synthesized reservoir rock, and fluids. The output of the vector network analyzer is both the dielectric constant, defined to be the real-portion complex permittivity, and the loss index, defined to be the imaginary portion. The loss tangent is a parameter that describes the overall efficacy of the material as a microwave absorber with higher values corresponding to higher heat generation in the reservoir. Reservoir properties of interest are isolated by taking advantage of experimentally defined synthesized cores. Variable properties are achieved by introducing a known quantity of specified materials to ensure control over the outcome of representative reservoir rock. Samples are an unconsolidated mixture of both the skeletal frame (rock matrix) as well as the pore space. The rock matrix is comprised of a systematic and stepwise variability of quartz sand, limestone sand, and kaolinite clay or bentonite clay. The fraction of each introduced mineral is manipulated to isolate the contribution of the individual components. The weights of the introduced constituents are calculated to result in a synthetic rock matrix with the desired rock mineralogy. The first batch of synthesized cores consisted of 75 mixtures. The remainder of the contrived cores were limestone. A separate 20 experiments were performed to account for the presence of both pore-filling and swelling clays, namely kaolinite and bentonite, respectively. Compaction and blending of the cores were performed by hand; homogenization of the mixture was ensured by thorough mixing.

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17

Barocela, Edward. "Secondary ion mass spectroscopy analysis of moisture penetration of dielectric films." Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films 4, no. 4 (July 1986): 1893–96. http://dx.doi.org/10.1116/1.573742.

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18

Black, C. T., and J. J. Welser. "Electric-field penetration into metals: consequences for high-dielectric-constant capacitors." IEEE Transactions on Electron Devices 46, no. 4 (April 1999): 776–80. http://dx.doi.org/10.1109/16.753713.

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19

Cossi, Maurizio, Nadia Rega, Giovanni Scalmani, and Vincenzo Barone. "Polarizable dielectric model of solvation with inclusion of charge penetration effects." Journal of Chemical Physics 114, no. 13 (April 2001): 5691–701. http://dx.doi.org/10.1063/1.1354187.

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20

Maruyama, Yuko, Hayato Kamata, Seiei Watanabe, Rio Kita, Naoki Shinyashiki, and Shin Yagihara. "Electric‐field penetration depth and dielectric spectroscopy observations of human skin." Skin Research and Technology 26, no. 2 (September 25, 2019): 255–62. http://dx.doi.org/10.1111/srt.12788.

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21

Guo, Zhanyong, Ping Guo, Guang Su, Demei Zhai, Fang Cheng, and Fachuang Li. "High-Temperature Permittivity and Microwave Pretreatment Characteristics of Nickel-Containing Sludge from Battery Production." Processes 7, no. 5 (May 3, 2019): 257. http://dx.doi.org/10.3390/pr7050257.

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Permittivity is a vitally important parameter for the description of the absorption and heating characteristics of materials under microwave irradiation. In this paper, the permittivity of nickel-containing sludge (NCS), which is created during battery production as a cheap secondary resource, was measured at temperatures from 20 °C to 600 °C at 2.45 GHz using the cavity perturbation method. In addition, the loss tangent (tanδ) and penetration depth (Dp) of microwaves into the material were calculated. The results of the permittivity study show that the dielectric constant (ε′) and dielectric loss factor (ε″) of the NCS increase with increasing temperature. The variations of the loss tangent (tanδ) and penetration depth (Dp) with the temperature can be divided into two parts at 200 °C. The effect of the initial moisture content on the dielectric properties of the material is notably greater than that of the temperature, which was confirmed by the heating curve. After microwave pretreatment, the nickel-containing phase is transformed into NiO, while the weight of NCS is reduced by more than 20%, the particle size is significantly reduced and the leaching time reduce 20 min than that of conventional heating.

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Bechtel, Timothy, Stanislav Truskavetsky, Gennadiy Pochanin, Lorenzo Capineri, Alexander Sherstyuk, Konstantin Viatkin, Tatyana Byndych, et al. "Characterization of Electromagnetic Properties of In Situ Soils for the Design of Landmine Detection Sensors: Application in Donbass, Ukraine." Remote Sensing 11, no. 10 (May 24, 2019): 1232. http://dx.doi.org/10.3390/rs11101232.

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To design holographic and impulse ground penetrating radar (GPR) sensors suitable for humanitarian de-mining in the Donbass (Ukraine) conflict zone, we measured critical electromagnetic parameters of typical local soils using simple methods that could be adapted to any geologic setting. Measurements were recorded along six profiles, each crossing at least two mapped soil types. The parameters selected to evaluate GPR and metal detector sensor performance were magnetic permeability, electrical conductivity, and dielectric permittivity. Magnetic permeability measurements indicated that local soils would be conducive to metal detector performance. Electrical conductivity measurements indicated that local soils would be medium to high loss materials for GPR. Calculation of the expected attenuation as a function of signal frequency suggested that 1 GHz may have optimized the trade-off between resolution and penetration and matched the impulse GPR system power budget. Dielectric permittivity was measured using both time domain reflectometry and impulse GPR. For the latter, a calibration procedure based on an in-situ measurement of reflection coefficient was proposed and the data were analyzed to show that soil conditions were suitable for the reliable use of impulse GPR. A distinct difference between the results of these two suggested a dry (low dielectric) soil surface, grading downward into more moist (higher dielectric) soils. This gradation may provide a matching layer to reduce ground surface reflections that often obscure shallow subsurface targets. In addition, the relatively high dielectric deeper (10 cm–20 cm) subsurface soils should provide a strong contrast with plastic-cased mines.

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Vasetsky, Yu M. "Penetration of non-uniform electromagnetic field into conducting body." Electrical Engineering & Electromechanics, no. 2 (April 10, 2021): 43–53. http://dx.doi.org/10.20998/2074-272x.2021.2.07.

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The study is based on the exact analytical solution for the general conjugation problem of three-dimensional quasi-stationary field at a flat interface between dielectric and conducting media. It is determined that non-uniform electromagnetic field always decreases in depth faster than uniform field. The theoretical conclusion is confirmed by comparing the results of analytical and numerical calculations. The concept of strong skin effect is extended to the case when penetration depth is small not only compare to the characteristic body size, but also when the ratio of the penetration depth to the distance from the surface of body to the sources of the external field is small parameter. For strong skin effect in its extended interpretation, the influence of external field non-uniformity to electromagnetic field formation both at the interface between dielectric and conducting media and to the law of decrease field in conducting half-space is analyzed. It is shown, at the interface the expressions for the electric and magnetic intensities in the form of asymptotic series in addition to local field values of external sources contain their derivatives with respect to the coordinate perpendicular to the interface. The found expressions made it possible to generalize the approximate Leontovich impedance boundary condition for diffusion of non-uniform field into conducting half-space. The difference between the penetration law for the non-uniform field and the uniform one takes place in the terms of the asymptotic series proportional to the small parameter to the second power and to the second derivative with respect to the vertical coordinate from the external magnetic field intensity at the interface.

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Novikova, G., I. Ershova, M. Prosviryakova, O. Mikhailova, V. Storchevoy, G. Larionov, G. Samarin, L. Kuleshova, D. Poruchikov, and L. Andreev. "Effect of heating of frozen colostrum in two-resonator installation." IOP Conference Series: Earth and Environmental Science 935, no. 1 (December 1, 2021): 012026. http://dx.doi.org/10.1088/1755-1315/935/1/012026.

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Abstract The study is aimed at the effect substantiation of voluminous heating of the cattle frozen colostrum in the two-resonator installation. The methodology is based on the theory of the electromagnetic field, the laws of thermodynamics and the results of physical modeling. The colostrum dielectric parameters were analyzed in the temperature range from -12 °C to +40 °C. The theoretical studies were carried out for changes finding out in the absorption coefficient of the electromagnetic field and the penetration depth of the electromagnetic waves 12.24 cm long during defrosting/heating of the cow colostrum with the fat content of 6.4%. It is found that the penetration depth of the electromagnetic field into the frozen raw material at negative temperatures range (0.2-1.0 cm) is less than that at the colostrum positive temperatures (1.0-2.17 cm). With such significant difference in the dielectric characteristics of the frozen and thawed colostrum and in their penetration depths of the ultra high frequency electromagnetic field, the rate of their heating is considerably different. The developed continuous-flow ultra high frequency electromagnetic generator contains two voluminous resonators. They provide the colostrum being in different physical states with different doses of the ultra high frequency electromagnetic field exposure.

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Robertson, P. K. "In situ testing and its application to foundation engineering." Canadian Geotechnical Journal 23, no. 4 (November 1, 1986): 573–94. http://dx.doi.org/10.1139/t86-086.

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The status of in situ testing and its application to foundation engineering are presented and discussed. The in situ test methods are discussed within the framework of three groups: logging, specific, and combined test methods. The major logging test methods discussed are standard penetration test (SPT), cone penetration test (CPT), and the flat plate dilatometer test (DMT). The major specific test methods discussed are the prebored pressuremeter test (PMT), the self-bored pressuremeter test (SBPMT), and the screw plate load test (SPLT). Discussion is also presented on recent tests that combine features of logging tests (using the CPT) and specific tests (e.g. the seismic, the electrical resistivity/dielectric, and the lateral stress sensing cone penetration tests). A brief discussion is also presented on the applicability, as perceived by the author, of existing in situ test methods and the future of in situ testing applied to foundation engineering. Key words: in situ testing, foundation engineering, penetration testing, pressuremeter.

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Ho, M. "Penetration of Em Fields into Circular Dielectric/Magnetic Container: Two-Dimensional Simulation." Journal of Electromagnetic Waves and Applications 25, no. 1 (January 2011): 111–22. http://dx.doi.org/10.1163/156939311793898314.

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27

He, Ming, Steven Novak, Lakshmanan Vanamurthy, Hassaram Bakhru, Joel Plawsky, and Toh-Ming Lu. "Cu penetration into low-k dielectric during deposition and bias-temperature stress." Applied Physics Letters 97, no. 25 (December 20, 2010): 252901. http://dx.doi.org/10.1063/1.3529492.

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28

Tanimoto, Satoshi, Hiromichi Oohashi, and Kazuo Arai. "Mechanism of Interlayer Dielectric Penetration Caused by Al Interconnection and Preventive Measures." ECS Transactions 6, no. 2 (December 19, 2019): 213–19. http://dx.doi.org/10.1149/1.2731187.

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29

Mazuré, C., J. Fitch, D. Denning, C. Gunderson, M. Haond, A. Straboni, B. Piot, and K. Barla. "Thin dielectric behavior and boron penetration under high temperature H2 SEG prebake." Microelectronic Engineering 15, no. 1-4 (October 1991): 479–82. http://dx.doi.org/10.1016/0167-9317(91)90268-i.

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30

Xin-Bo, Wang, Bai He, Sun Qin-Fen, Yin Xin-She, Zhang Hong-Tai, and Cui Wan-Zhao. "Experimental study of multipactor on dielectric of penetration flange for vacuum chamber." Acta Physica Sinica 70, no. 12 (2021): 127901. http://dx.doi.org/10.7498/aps.70.20210106.

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31

Borowicz, Paweł. "Depth-Sensitive Raman Investigation of Metal-Oxide-Semiconductor Structures: Absorption as a Tool for Variation of Exciting Light Penetration Depth." Journal of Spectroscopy 2016 (2016): 1–14. http://dx.doi.org/10.1155/2016/1617063.

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Presented work focuses the attention on two regions of MOS structure placed in the vicinity of the semiconductor/dielectric interface, in particular: on part of dielectric layer and thin layer of the substrate. In the presented work the application of absorption as a tool that can vary the absorption depth of excitation light into the semiconductor substrate is discussed. The changes of the absorption depth of visible light allows to obtain Raman signal from places in the substrate placed at different distances from the dielectric/semiconductor interface. The series of Raman spectra obtained from visible excitation in the case of varying absorption depth allowed to analyze the structure of the substrate as a function of distance from the interface. Deep ultraviolet Raman study regarding part of silicon dioxide layer placed directly at the interface is not discussed so far which makes the analysis of the structure of this part of dielectric layer possible. Comparison of reported in this work Raman data with structure of silicon/silicon dioxide interface obtained from other experimental techniques proves the applicability of proposed methodology.

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32

Usman, Fahad, John Ojur Dennis, Fabrice Meriaudeau, Abdelaziz Yousif Ahmed, Khe Cheng Seong, Yap Wing Fen, Amir Reza Sadrolhosseini, et al. "Dependence of the Optical Constant Parameters of p-Toluene Sulfonic Acid-Doped Polyaniline and Its Composites on Dispersion Solvents." Molecules 25, no. 19 (September 25, 2020): 4414. http://dx.doi.org/10.3390/molecules25194414.

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The optical constants of Para-Toluene sulfonic acid-doped polyaniline (PANI), PANIchitosan composites, PANI-reduced graphene-oxide composites and a ternary composite comprising of PANI, chitosan and reduced graphene-oxide dispersed in diluted p-toluene sulfonic acid (PTSA) solution and N-Methyl-2-Pyrrolidone (NMP) solvent have been evaluated and compared. The optical constant values were extracted from the absorbance spectra of thin layers of the respective samples. The potential utilization of the materials as the active sensing materials of surface plasmon resonance biosensors has also been assessed in terms of the estimated value of the penetration depth through a dielectric medium. The results show a reasonable dependence of the optical constant parameters on the solvent type. Higher real part refractive index (n) and real part complex dielectric permittivity (ε’) values were observed for the samples prepared using PTSA solution, while higher optical conductivity values were observed for the NMP-based samples due to their relatively higher imaginary part refractive index (k) and imaginary part complex dielectric permittivity (ε″) values. In addition, NMP-based samples show improvement in terms of the penetration depth through a dielectric medium by around 9.5, 1.6, 4.4 and 2.9 times compared to PTSA-based samples for the PANI, PANI-chitosan, PANI-RGO and the ternary composites, respectively. Based on these, it is concluded that preparation of these materials using different dispersion solvents could produce materials of different optical properties. Thus, the variation of the dispersion solvent will allow the flexible utilization of the PANI and the composites for diverse applications.

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33

Ma, Aiyuan, Xuemei Zheng, Lei Gao, Kangqiang Li, Mamdouh Omran, and Guo Chen. "Investigations on the Thermodynamics Characteristics, Thermal and Dielectric Properties of Calcium-Activated Zinc-Containing Metallurgical Residues." Materials 15, no. 3 (January 18, 2022): 714. http://dx.doi.org/10.3390/ma15030714.

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An activate pretreatment of zinc-containing metallurgical residues were proposed by adding CaO and introducing microwave heating approach into the CaO activation pretreatment process to realize the conversion of refractory ore phases into pre-treated ore phase. Thermodynamic characteristics analysis indicated that adding CaO can realize the conversion of refractory ore phases, with the same effect as the carbon additives. Thermal conductivity properties analysis denoted that the thermal conductivity properties of ZnS and ZnFe2O4 were relatively poor. Meanwhile, the thermal conductivity properties of the residues sample added with 25% CaO were significantly superior to the residues added with other CaO contents, with the maximum specific heat value of 1.348 J/g·K at 350 °C. Dielectric properties analysis highlighted that adding CaO with the dielectric constant properties significantly higher than that of other substances can enhance the microwave absorption capacity of zinc-containing residues. The decrease in dielectric loss and loss tangent value with the increase of temperature and the residues having large microwave penetration depth guaranteed to obtain better uniformity of microwave heating. Furthermore, adding 25% CaO promoted the microwave penetration depth of the residues sample increased in the range of 300–500 °C. This work can lay a theoretical research foundation for solving the key difficulty for efficient Zn recovery from complex zinc-containing metallurgical residues.

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34

Lee, Chih-Yen, Chi-Yang Yan, and Yi-Lung Cheng. "In-Situ Repair Plasma-Induced Damage and Cap Dielectric Barrier for Porous Low-Dielectric-Constant Materials by HMDS Plasma Treatment." Coatings 11, no. 3 (March 9, 2021): 314. http://dx.doi.org/10.3390/coatings11030314.

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Plasma damage and metal ion penetration are critical issues for porous low-dielectric-constant (low-k) materials used in the back-end-of-line interconnects. This study proposed a novel process with in-situ repairing plasma-induced damage and capping a barrier for porous low-k materials by Hexamethyldisilazane (HDMS) plasma treatment. For a plasma-damaged porous low-k material, its surface hydrophilic state was transformed to hydrophobic state by HDMS plasma treatment, revealing that damage was repaired. Simultaneously, a dielectric film was capped onto the porous low-k material, and displayed better barrier capability against Cu migration. Additionally, the breakdown reliability of the stacked dielectric was enhanced by the means of HDMS plasma treatment. The optimized HDMS plasma treatment time was found to be 10 s. Therefore, this proposed HDMS plasma treatment processing is a promising technique for highly applicable low-k material used for advanced technology nodes.

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35

Arcone, Steven A., Daniel E. Lawson, Allan J. Delaney, Jeffrey C. Strasser, and Jodie D. Strasser. "Ground‐penetratinng radar reflection profiling of groundwater and bedrock in an area of discontinuous permafrost." GEOPHYSICS 63, no. 5 (September 1998): 1573–84. http://dx.doi.org/10.1190/1.1444454.

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We have used ground‐penetrating radar to profile the depth of permafrost, to groundwater beneath permafrost, and to bedrock within permafrost in alluvial sediments of interior Alaska. We used well log data to aid the interpretations and to calculate dielectric permittivities for frozen and unfrozen materials. Interfaces between unfrozen and frozen sediments above permafrost were best resolved with wavelet bandwidths centered at and above 100 MHz. The resolution also required consideration of antenna configuration, season, and surface conditions. Depths to subpermafrost groundwater were profiled where it was in continuous contact with the bottom of the permafrost, except near transitions to unfrozen zones, where the contact appeared to dip steeply. The complexity of the responses to intrapermafrost bedrock, detected at a maximum depth of 47 m, appears to distinguish these events from those of subpermafrost saturated sediments. The relative dielectric permittivity ranged between 4.4 and 8.3 for the permafrost, and between 12 and 45 for partially to fully saturated, unfrozen silts and sands. Scattering losses are evident from intrapermafrost diffractions and from the improved penetration achieved by lowering the midband radar frequency from 100 to 50 MHz.

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36

Li, Shuang, Yongqiang Fu, Xinzheng Guo, Jianjun Li, and Ruobing Zhang. "Penetration of plasma jet into porous dielectric layer: confirmed by surface charge dissipation of silicone rubber." Journal of Physics D: Applied Physics 55, no. 21 (February 25, 2022): 215202. http://dx.doi.org/10.1088/1361-6463/ac5557.

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Abstract The penetration of plasma in the porous structure is important for its application in plasma catalysis, plasma medicine, etc. In this paper, the penetration of plasma species in the porous kaolin layer was investigated. The silicone rubber was chosen as a probe and the inorganic porous dielectric layer was constructed with granular kaolin coated on the surface of silicone rubber. AC and pulsed plasma jets were applied to the silicone rubber, and the surface charge dissipation of bulk silicone rubber was measured to characterize the changes of surface property caused by the plasma penetration. The results showed that plasma could penetrate the porous dielectric layer on the silicone rubber and interact with the surface of silicone rubber, thus accelerating the surface charge dissipation of the bulk silicone rubber. The increase of shallow traps and surface conductivity after plasma treatment was the main reason for the acceleration of surface charge dissipation. The surface charge dissipation is enhanced with the increase of treatment time and the generating voltage of plasma. The surface charge dissipation declined for silicone rubber with a thicker kaolin layer due to the blocking of the kaolin layer on the interaction of plasma and the silicone rubber. For the same kind of plasma, the charge dissipation rate was linearly related to plasma dose which was represented by the energy density of plasma applied on the coated silicone rubber. At the same energy density, the surface charge dissipation of silicone rubber after pulsed plasma treatment was faster than that of AC plasma.

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37

Anderson, J. L. Ross, Ronald L. Koder, Christopher C. Moser, and P. Leslie Dutton. "Controlling complexity and water penetration in functional de novo protein design." Biochemical Society Transactions 36, no. 6 (November 19, 2008): 1106–11. http://dx.doi.org/10.1042/bst0361106.

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Natural proteins are complex, and the engineering elements that support function and catalysis are obscure. Simplified synthetic protein scaffolds offer a means to avoid such complexity, learn the underlying principles behind the assembly of function and render the modular assembly of enzymatic function a tangible reality. A key feature of such protein design is the control and exclusion of water access to the protein core to provide the low-dielectric environment that enables enzymatic function. Recent successes in de novo protein design have illustrated how such control can be incorporated into the design process and have paved the way for the synthesis of nascent enzymatic activity in these systems.

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38

Arcone, Steven, David Finnegan, and Ginger Boitnott. "GPR characterization of a lacustrine UXO site." GEOPHYSICS 75, no. 4 (July 2010): WA221—WA239. http://dx.doi.org/10.1190/1.3467782.

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We used [Formula: see text] ground-penetrating-radar (GPR) reflection profiles to determine if high-explosive (HE) depth bombs were possibly detonated within a small New England lake formerly used as a bombing range, as well as the depths and distribution of inert and possibly unexploded ordnance (UXO) within the subbottom sediments. Maximum water depth was [Formula: see text]. The primary munitions were unarmed practice bombs, but terrestrial fragments from HE depth bombs led us to seek stratigraphic obliteration and distortion as evidence of their use. The low water conductivity and quartz-rich sediments provided more than [Formula: see text] of subbottom penetration beneath slope and shelf sediments. The high permittivities of the water and subbottom sediments provided good antenna directivity, excellent 2D migrations, multicentimeter vertical resolution, and a unique pulse waveform signature for metal objects. Our line profiles revealed hundreds of subbottom diffractions, which implied an areal distribution of thou-sands of suspicious objects. Most lay beneath the central basin, but many resided beneath the slopes and shelves as well. Supplementary profiles of a nearby pristine lake and of controlled munitions, a side-scan sonar bottom survey, and time-domain reflectometry dielectric measurements of sediment samples corroborated our findings of natural stratigraphy, a unique metallic diffraction phase signature, the existence of many nonmetallic objects including logs, and subbottom relative permittivities ranging from 28 to 76. The intact natural lacustrine strata, including deltaic foresets and bottom sets, faults, and conformable and unconformable horizons, suggest that live bombs likely did not detonate in the lake. The only stratigraphic disturbances we found were apparent perforations beneath about [Formula: see text] of water, within which diffractions of metallic origin originated. The dielectric results and the prominent slope strata over the deepest horizons led us to conclude that the exceptional subbottom penetration existed under predominantly sandy sediments.

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39

Dwyer, John J., Apostolos G. Gittis, Daniel A. Karp, Eaton E. Lattman, Daniel S. Spencer, Wesley E. Stites, and Bertrand García-Moreno E. "High Apparent Dielectric Constants in the Interior of a Protein Reflect Water Penetration." Biophysical Journal 79, no. 3 (September 2000): 1610–20. http://dx.doi.org/10.1016/s0006-3495(00)76411-3.

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40

Geyter, N. De, R. Morent, and C. Leys. "Penetration of a dielectric barrier discharge plasma into textile structures at medium pressure." Plasma Sources Science and Technology 15, no. 1 (January 6, 2006): 78–84. http://dx.doi.org/10.1088/0963-0252/15/1/012.

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41

Hang-Ting Lue, Juh-Tzeng Lue, and Tseung-Yuen Tseng. "Microwave penetration depth measurement for high T/sub c/ superconductors by dielectric resonators." IEEE Transactions on Instrumentation and Measurement 51, no. 3 (June 2002): 433–39. http://dx.doi.org/10.1109/tim.2002.1017712.

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42

El-Hajj, A., and K. Y. Kabalan. "Scattering from and penetration into a dielectric-filled conducting cylinder with multiple apertures." IEEE Transactions on Electromagnetic Compatibility 36, no. 3 (1994): 196–200. http://dx.doi.org/10.1109/15.305454.

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43

Chen, Ching Mu, Shen Yuar Chen, Wei Ching Chuang, and Jen Yu Shieh. "Transparent Glass Window with Energy-Saving and Heat Insulation Capabilities." Advanced Materials Research 314-316 (August 2011): 10–16. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.10.

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This paper proposes capabilities of transparent glass window design with energy-saving and heat insulation for carbon reduction issues. An optical thin film coating technology is used for coating multilayered dielectric materials on the transparent glass to achieve an infrared ray shielding effect; especially to prevent rising temperature easily of indoor room. That is infrared ray incidence from outdoor and the thermal flux effect of the transparent window influent the indoor room temperature. In winter, the outdoor temperature is increased more easily by infrared ray incidence. However, the heat insulation window allows 98% of visible light penetration through the window and also allows 90% of infrared light reflection and roughly 10% of infrared light penetration into indoor.

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44

Krausová, A., J. Macák, and M. Novák. "Ex-situ characterization of pre- and post-transient specimens of Zr1Nb alloys." Koroze a ochrana materialu 59, no. 1 (April 22, 2015): 19–23. http://dx.doi.org/10.1515/kom-2015-0008.

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Abstract The ex-situ tests were performed with Zr1Nb alloy specimens that had been pre-exposed to the environment with an elevated concentration of lithium (70 ppm Li as LiOH) at the temperature of 360 °C for a period of 63 to 77 days prior to the measurement. The impedance changes at the phase alloy- -oxide-electrolyte interface were monitored using the ex-situ electrochemical impedance spectroscopy. At the same time, the progress of electrolyte penetration in the oxide porous structure was studied. The oxidic layer and the electrolyte penetration are characterized by the elements of the equivalent circuit model and Jonscher analysis that enables calculation of the dielectric thickness of the oxide.

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45

Abea, Andres, Pere Gou, Maria Dolors Guardia, Sancho Bañon, and Israel Muñoz. "Combined Effect of Temperature and Oil and Salt Contents on the Variation of Dielectric Properties of a Tomato-Based Homogenate." Foods 10, no. 12 (December 16, 2021): 3124. http://dx.doi.org/10.3390/foods10123124.

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Tomato-based processed foods are a key component of modern diets, usually combined with salt and olive oil in different ratios. For the design of radiofrequency (RF) and microwave (MW) heating processes of tomato-based products, it is of importance to know how the content of both ingredients will affect their dielectric properties. Three concentrations of olive oil and salt were studied in a tomato homogenate in triplicate. The dielectric properties were measured from 10 to 3000 MHz and from 10 to 90 °C. Interaction effects were studied using a general linear model. At RF frequencies, the dielectric constant decreased with increasing temperature in samples without added salt, but this tendency was reversed in samples with added salt. The addition of salt and oil increased the frequency at which this reversion occurred. At MW frequencies, the dielectric constant decreased with increasing temperature, salt, and oil content. The loss factor increased with increasing salt content and temperature, except in samples without added salt at 2450 MHz. Penetration depth decreased with increasing frequency and loss factor. Salt and oil contents have a significant effect on the dielectric properties of tomato homogenates and must be considered for the design of dielectric heating processes.

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46

Itocazu, V. T., V. Sonnenberg, J. A. Martino, E. Simoen, and Cor Clayes. "Ground Plane Influence on Analog Parameters of Different UTBB nMOSFET Technologies." Journal of Integrated Circuits and Systems 12, no. 2 (December 28, 2017): 82–88. http://dx.doi.org/10.29292/jics.v12i2.455.

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This paper presents an analysis of the silicon film thickness (6 nm and 14 nm), the gate dielectric material (SiO2 and High- κ material) and the Ground Plane influence on the analog parameters of Ultra Thin Body and Buried Oxide (UTBB) SOl nMOSFET devices, based on experimental and simulation results. Two channel lengths (70 nm and 1μm) have been considered and the analog performance has been analyzed as a function of the back gate bias. It is shown that at zero back gate bias , the presence of a Ground Plane improves the transconductance in the saturation region due to the strong coupling between front and back gates in devices with a long channel (1 μm), thin silicon film (6 nm) and SiO2 as gate dielectric material. However, for the intrinsic voltage gain, output conductance and Early Voltage, the devices without Ground Plane present better results due to the higher drain electrical field penetration. Short-channel transistors (70 nm) with Ground Plane show an improvement of the analog parameters also due to the high drain electrical field penetration. Similar behavior is noticed in devices with a thicker silicon film (14nm). UTBB nMOSFETs with High- κ material present less influence of a Ground Plane on the parameters analyzed. Varying the back gate bias in devices with long channel (1 μm) and SiO2 as gate dielectric material, the analog parameters present better results in devices without Ground Plane, except for the transconductance in long channel transistors with a thin silicon film, for the reason explained before (strong coupling between front and back gates). Devices with High-κ material as gate dielectric show a minor improvement of the analog performance with a Ground Plane.

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47

M Guardeño, L., M. Hernández-Carrión, J. M Catala-Civera, P. Plaza, I. Pérez-Munuera, and I. Hernando. "Improving Microwave Heating using Polysaccharides as Thickeners." Czech Journal of Food Sciences 27, Special Issue 1 (June 24, 2009): S342—S345. http://dx.doi.org/10.17221/1085-cjfs.

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The aim of this work was to improve microwave heating in white sauces using different polysaccharides in their formulation; ι-, λ- and &kappa-carrageenan and native and modified starches were used as thickeners. Five model systems were prepared, each one with a different polysaccharide, salt, and water. Dielectric loss factor (ε'') was measured and penetration depth of the electric field was calculated at 20 and 40°C at 2450 GHz. The results showed that ε'' increased significantly (P < 0.05) when temperature rose in all the model systems. Moreover, ε'' decreased significantly (P < 0.05) when the polysaccharide concentration rose in the systems elaborated with starch (both native and modified). The penetration depth increased significantly at 40°C when native starch concentration rose. Not significant differences due to the thickener concentration were found in the depth penetration values in the other model systems, both at 20 and 40°C.

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48

Beverte, Ilze, Ugis Cabulis, and Sergejs Gaidukovs. "Polytetrafluoroethylene Films in Rigid Polyurethane Foams’ Dielectric Permittivity Measurements with a One-Side Access Capacitive Sensor." Polymers 13, no. 7 (April 6, 2021): 1173. http://dx.doi.org/10.3390/polym13071173.

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As a non-metallic composite material, widely applied in industry, rigid polyurethane (PUR) foams require knowledge of their dielectric properties. In experimental determination of PUR foams’ dielectric properties protection of one-side capacitive sensor’s active area from adverse effects caused by the PUR foams’ test objects has to be ensured. In the given study, the impact of polytetrafluoroethylene (PTFE) films, thickness 0.20 mm and 0.04 mm, in covering or simulated coating the active area of one-side access capacitive sensor’ electrodes on the experimentally determined true dielectric permittivity spectra of rigid PUR foams is estimated. Penetration depth of the low frequency excitation field into PTFE and PUR foams is determined experimentally. Experiments are made in order to evaluate the difference between measurements on single PUR foams’ samples and on complex samples “PUR foams + PTFE film” with two calibration modes. A modification factor and a small modification criterion are defined and values of modifications are estimated in numerical calculations. Conclusions about possible practical applications of PTFE films in dielectric permittivity measurements of rigid PUR foams with one-side access capacitive sensor are made.

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49

Maity, Niladri Pratap, and Reshmi Maity. "Surface Plasmon Polaritons: Propagation Characteristics of Surface Plasmon Waves on Au and Ag at Optical Wavelengths." Applied Mechanics and Materials 110-116 (October 2011): 764–68. http://dx.doi.org/10.4028/www.scientific.net/amm.110-116.764.

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The existence of Surface Plasmons (SPs) is possible only if the metal have a negative dielectric constant at the corresponding optical frequency. In this paper the propagation characteristics of Surface Plasmon Waves (SPWs) which exists on noble metals like gold (Au) and silver (Ag) due to the formation of Surface Plasmon Polaritons (SPPs), have been evaluated theoretically and simulated with the help of MATLAB programming language. The variation of the propagation constant (PC), the attenuation coefficient (AC) and the penetration depth (PD) inside the metals and the dielectric has been determined. It has been found that highly conducting metals Au and Ag provide a strong confinement to the SPWs at optical frequencies.

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50

Abdelmawla, Ahmad, and S. Sonny Kim. "Application of Ground Penetrating Radar to Estimate Subgrade Soil Density." Infrastructures 5, no. 2 (January 27, 2020): 12. http://dx.doi.org/10.3390/infrastructures5020012.

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Ground penetrating radar (GPR) technology has been widely used in pavement assessment over the last decade. Assessing the subgrade condition and monitoring its temporal variation provide valuable information regarding changes associated with pavement deterioration, allowing for the beneficial prediction of future road maintenance. This paper presents a method to estimate the density and water content of prepared subgrade soils of highly plastic silt using a 2 GHz GPR scan system and a simple exponential model. A bulk density prediction model was developed based on electromagnetic mixing theory to back calculate subgrade soils density. The model developed determines the soil’s dielectric constant, considering dielectric and volumetric properties of the three major components of soil: air, water, and solid particles. A series of laboratory tests was conducted on six (6) soil samples at various density levels to validate the newly developed model. For validation purposes, sand cone and dynamic cone penetration (DCP) tests were performed and compared with the estimated soils strength from GPR data. The results show that the prediction of soils density and stiffness using nondestructive technology helps efficiently forecast not only pavement deterioration, but potential risks to the subsurface pavement structure with all the advances of time saving using air coupled GPR antenna mounted on a moving vehicle.

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