scholarly journals The Potential Scope of the Ultrasonic Surface Reflection Method Towards Mechanical Characterisation of Isotropic Materials. Part 1. A Theoretical Analysis

2021 ◽  
Author(s):  
V. Tinard ◽  
P. François ◽  
C. Fond
Keyword(s):  
Theoretical Analysis ◽  
Reflection Method ◽  
Surface Reflection ◽  
Isotropic Materials ◽  
Mechanical Characterisation

A NOVEL OF SURFACE REFLECTION METHOD USING RADIO-WAVE FOR SOIL DENSITY ESTIMATION

2014 ◽  
Vol 38 ◽  
pp. 53-61
Author(s):  
Mardeni Bin Roslee ◽  
Intan Suraya Shahdan ◽  
Khazaimatol Shima Subari
Keyword(s):  
Radio Wave ◽  
Density Estimation ◽  
Soil Density ◽  
Reflection Method ◽  
Surface Reflection

scholarly journals Study on the Viscoelasticity Measurement of Materials Based on Surface Reflected Waves

Materials ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 1875 ◽  
Author(s):  
Jun-jie Chang ◽  
Yuan-yuan Li ◽  
Xue-feng Zeng ◽  
Hai-ying Zhong ◽  
Tao-lei Wan ◽  
...  
Keyword(s):  
Theoretical Study ◽  
Loss Modulus ◽  
Experimental System ◽  
Ultrasonic Waves ◽  
Reflection Method ◽  
Multiple Reflections ◽  
Reflected Waves ◽  
Surface Reflection ◽  
Overall Efficiency

The reflected waves received from ultrasonic waves propagating in materials contain information that constitutes the physical properties, material composition, defects, and degradation states. When measuring the dynamic viscoelasticity, the traditional bottom reflection method (BRM) cannot be used to measure the bottom irregular samples. In this paper, the storage modulus, loss modulus, and loss tangent are extracted by the surface reflection method (SRM) to evaluate the elastomer sample viscoelasticity. A theoretical study on the phase change caused by multiple reflections in the case of non-thin layer coupling is conducted. Based on this research, the experimental system is built. The results show that considering the thickness of the coupling layer can optimize the determination of viscoelasticity and reduce the error of the viscoelastic evaluation results of an elastomer with the traditional BRM. Finally, based on the principle of the SRM, the density of the elastomers is measured, and the feasibility and overall efficiency of this method are verified by experiments.

scholarly journals Characterization Analysis of Textured and Diffused Monocrystalline Silicon Wafer

2021 ◽  
Vol 17 (17) ◽  
Author(s):  
Asrafusjaman Rubel ◽  
M. A. Kabir ◽  
Masud Rana ◽  
Ariful Islam ◽  
Md. Shawkut Ali Khan
Keyword(s):  
Sheet Resistance ◽  
Silicon Wafer ◽  
Surface Photovoltage ◽  
Reflection Method ◽  
Characteristic Analysis ◽  
Phosphorus Doping ◽  
Minority Carrier Diffusion Length ◽  
Surface Reflection ◽  
Pyramid Structure ◽  
P Type

This paper focuses on examining the characteristic analysis of the textured and diffused silicon wafer. Characterization performance of the textured and diffused wafer using surface reflection method, sheet resistance method, SEM, and surface photovoltage method is examined. From the SRM result, it is observed that the reflection of the textured wafer is lower than the raw wafer. This means that the textured wafer forms the pyramid structure, which was measured by SEM. Sheet resistance measures the resistivity of the raw wafer and after phosphorous diffusion into the p-type silicon, the wafer are 2.3 Ω-cm and 0.80 Ω-cm respectively. From the sheet resistance results, it is observed that the phosphorus doping is properly done. The Surface Photovoltage (SPV) result shows that minority carrier diffusion length and lifetime for a solar cell is 86.4μm and 2.8 μsec respectively.

scholarly journals Microwave Surface Reflection Method for Soil Moisture Determination Using frequency of 1.7-2.6 GHz

2015 ◽  
Vol 9 (13) ◽  
pp. 71
Author(s):  
Yap C. W. ◽  
Mardeni R. ◽  
Ahmad N. N.
Keyword(s):  
Soil Moisture ◽  
Horn Antenna ◽  
Moisture Determination ◽  
Reflection Method ◽  
Surface Reflection ◽  
System A ◽  
Minimal Data ◽  
Critical Components ◽  
Ground Penetrating ◽  
High Degree

Soil moisture is one of the critical components to be investigated in civil, geological and agricultural works. This is because the parameter can affect the physical and electromagnetic characteristics of soil, such as density and permittivity and this can further restricts soil application. Unfortunately, finding a suitable non-destructive model for accurate soil moisture determination is challenging. In this article, the concept and development of soil moisture determination via ground penetrating radar (GPR) principle and surface reflection method is explained. The system is designed to be used with standard horn antenna with a frequency of 1.7-2.6 GHz along with vector network analyzer (VNA). The proposed system can measure soil moisture of three types of soil samples such as sand, loamy, and clay with high degree of accuracy. In this research, microwave surface reflection method is applied to analyze the effect of soil moisture with its electrical properties using our novel GPR principle. The result of the research is promising with high percentage of agreement with Topp theoretical value. The values are 31% to 61% for sand, 5% to 42% for clay, and 44% to 54% for loamy. For validation on the system, a new type of soil is used for measurement, and the result has an accuracy of 93%. By using the proposed developed models, soil moisture estimation can be easily determined with minimal data input through a novelty GPR surface reflection method.

scholarly journals Comparative Study on Viscoelastic Evaluation Methods of Polymer Materials Based on Ultrasonic Method

Materials ◽  
2019 ◽  
Vol 12 (18) ◽  
pp. 2948 ◽  
Author(s):  
Li ◽  
Chang ◽  
Huang ◽  
Tang
Keyword(s):  
Elastic Modulus ◽  
Frequency Domain ◽  
Ultrasonic Method ◽  
Ultrasonic Sensor ◽  
Polymer Materials ◽  
Center Frequency ◽  
Reflection Method ◽  
Surface Reflection ◽  
Practical Performance ◽  
Variation Trends

Rubber, as a kind of macromolecular material often used in large ships, aviation, aerospace, and other fields, has remarkable viscoelasticity at room temperature. Therefore, it is of great significance to evaluate the viscoelastic properties of polymer composites. In this paper, four kinds of rubber materials are taken as research objects. Based on the principle of ultrasonic detection, the viscoelastic evaluation of the sample materials is carried out through experiments and simulations. On the basis of previous research, the surface reflection method (SRM) and the bottom reflection method (BRM) are compared in depth. First, the spectrum of received signals is analyzed, and the storage elastic modulus, loss elastic modulus, attenuation coefficient and loss tangent value are obtained. Secondly, the results of the BRM and the SRM are compared and analyzed in the frequency domain of –6 dB. The results show that both the SRM and BRM are feasible in the evaluation of the viscoelasticity of the material, and the variation trends observed for the above-mentioned parameters in the effective frequency domain are consistent, especially at the center frequency. Finally, aiming at the mode transformation of the acoustic wave around the ultrasonic sensor, the practical performance of the surface reflection method is optimized by increasing the diameter of the ultrasonic sensor.

Microdiffraction Patterns of Small Metallic Particles II; Theoretical Analysis

1982 ◽  
Vol 40 ◽  
pp. 668-669
Author(s):  
A. Gómez ◽  
P. Schabes-Retchkiman ◽  
M. José-Yacamán ◽  
T. Ocaña
Keyword(s):  
Experimental Data ◽  
Electron Diffraction ◽  
Theoretical Analysis ◽  
Size Range ◽  
Dynamical Theory ◽  
Metallic Particles ◽  
Splitting Effect

The splitting effect that is observed in microdiffraction pat-terns of small metallic particles in the size range 50-500 Å can be understood using the dynamical theory of electron diffraction for the case of a crystal containing a finite wedge. For the experimental data we refer to part I of this work in these proceedings.

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