Determination of the metal nanometer layer thickness and semiconductor conductivity in metal-semiconductor structures from electromagnetic reflection and transmission spectra

2006 ◽  
Vol 51 (5) ◽  
pp. 644-649 ◽  
Author(s):  
D. A. Usanov ◽  
A. V. Skripal ◽  
A. V. Abramov ◽  
A. S. Bogolyubov
Keyword(s):  
Layer Thickness ◽  
Transmission Spectra ◽  
Reflection And Transmission ◽  
Semiconductor Structures ◽  
Semiconductor Conductivity

Precise Determination of Band Gap Naturally via Absorption/Reflectance/Transmission Spectra

2014 ◽  
Vol 509 ◽  
pp. 3-8 ◽  
Author(s):  
Ya Jie Liu ◽  
Ning Zhu
Keyword(s):  
Experimental Data ◽  
Band Gap ◽  
Material Property ◽  
Calculated Data ◽  
Precise Determination ◽  
Transmission Spectra ◽  
Spectroscopy Data ◽  
Reflection And Transmission ◽  
Experimental Spectroscopy

A set of nonlinear equations about the band gap and the indexnof material property with the absorptance, reflectance and transmittance were produced based on Tauc relation. Optimizing fitting the experimental spectroscopy data, such as absorption, reflection and transmission, the band gapand the indexnrelated to the material property could be obtained accurately and reliably. Meanwhile, the experimental data were used as more as possible, and the artificial errors at pre-determining the indexnwere avoided. The lowest correlation coefficient and the largest average relative error between the experimental and the calculated data are 0.9588 and 2.7% in all considered cases respectively. The best results show the band gap obtained from this method is more accurate, easier and faster than traditional extrapolation. Hence, this work would promote the precision and reliability for predicting the band gap and index of materials naturally.

Application of 3D-printing technologies for production of master-model in engineering industry

2021 ◽  
Vol 0 (9) ◽  
pp. 17-21
Author(s):  
O. A. Dvoryankin ◽  
◽  
N. I. Baurova ◽  
Keyword(s):  
3D Printing ◽  
Layer Thickness ◽  
Ultimate Strength ◽  
3D Models ◽  
Engineering Industry ◽  
Master Model ◽  
Parameter Influence ◽  
Printing Parameter

Analysis of 3D-printing methods used in the molding production to manufacture master-models has been carried out. The technology was selected, which allowed one to make high-precision parts, combining the molding and the 3D-printing. Factors effecting on the quality of 3D-models printed by this technology were analyzed. Experimental studied for determination of the printing parameter influence (layer thickness, filling percentage, printing velocity) on ultimate strength of specimens made of ABS-plastic were carried out.

scholarly journals WAVE TRANSMISSION THROUGH TRAPEZOIDAL BREAKWATERS

1978 ◽  
Vol 1 (16) ◽  
pp. 129 ◽  
Author(s):  
Ole Secher Madsen ◽  
Paisal Shusang ◽  
Sue Ann Hanson
Keyword(s):  
Energy Dissipation ◽  
Approximate Method ◽  
Cross Section ◽  
Wave Energy ◽  
Graphical Form ◽  
Dissipated Energy ◽  
Simple Method ◽  
Reflection And Transmission ◽  
Transmission Coefficients

In a previous paper Madsen and White (1977) developed an approximate method for the determination of reflection and transmission characteristics of multi-layered, porous rubble-mound breakwaters of trapezoidal cross-section. This approximate method was based on the assumption that the energy dissipation associated with the wave-structure interaction could be considered as two separate mechanisms: (1) an external, frictional dissipation on the seaward slope; (2) an internal dissipation within the porous structure. The external dissipation on the seaward slope was evaluated from the semi-theoretical analysis of energy dissipation on rough, impermeable slopes developed by Madsen and White (1975). The remaining wave energy was represented by an equivalent wave incident on a hydraulically equivalent porous breakwater of rectangular cross-section. The partitioning of the remaining wave energy among reflected, transmitted and internally dissipated energy was evaluated as described by Madsen (1974), leading to a determination of the reflection and transmission coefficients of the structure. The advantage of this previous approximate method was its ease of use. Input data requirements were limited to quantities which would either be known (water depth, wave characteristics, breakwater geometry, and stone sizes) or could be estimated (porosity) by the design engineer. This feature was achieved by the employment of empirical relationships for the parameterization of the external and internal energy dissipation mechanisms. General solutions were presented in graphical form so that calculations could proceed using no more sophisticated equipment than a hand calculator (or a slide rule). This simple method gave estimates of transmission coefficients in excellent agreement with laboratory measurements whereas its ability to predict reflection coefficients left a lot to be desired.

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