Position of Polarized Impurity Absorption Bands and Orientation Statistics of Impurity Molecules in Uniaxial Polymer Films

2000 ◽  
Vol 89 (1) ◽  
pp. 30 ◽  
Author(s):  
E. M. Aver’yanov
Keyword(s):  
Polymer Films ◽  
Absorption Bands ◽  
Impurity Absorption ◽  
Orientation Statistics

The Effects of Deoxidants on Ge-Se-Te Chalcogenide Glasses

2011 ◽  
Vol 103 ◽  
pp. 458-463
Author(s):  
Xun Si Wang ◽  
Jie Sun ◽  
Qiu Hua Nie ◽  
Shi Xun Dai ◽  
Xiang Hua Zhang ◽  
...  
Keyword(s):  
Chalcogenide Glasses ◽  
Transmission Spectra ◽  
Absorption Bands ◽  
Minimum Concentration ◽  
Impurity Absorption ◽  
Ir Transmission ◽  
Different Content ◽  
The Relationship ◽  
Concentration Of Impurities ◽  
Main Impurity

In order to decrease the impurity absorption bands of Ge-Se-Te chalcogenide glasses in IR region. Three different kinds of deoxidants including Mg(magnesium), Al(aluminium) and Ca(calcium) were chosen. Properties measurements including density, Vis-NIR and infrared (IR) transmission spectra were adopted to analyze the relationship between impurity absorption bands and deoxidants. The concentrations of impurities in glass samples with different content of Mg were calculated by method of optic spectra. The results show that Mg is a better choice as deoxidant for chalcogenide glasses compared to Al and Ca. The values of main impurity concentration decrease from 4417.833 to 0 ppmw for Ge-O and from 55.236 to 0 ppmw for Si-O with increasing content of Mg, respectively. At least 200ppm Mg is needed to minimize the main absorption bands in IR region and G5 glass incorporated with 400ppm Mg has minimum concentration of impurities which means that it possesses the optimal transmission properties.

Shapes of Impurity Absorption Bands in Solids

1965 ◽  
Vol 140 (2A) ◽  
pp. A601-A617 ◽  
Author(s):  
Thomas H. Keil
Keyword(s):  
Absorption Bands ◽  
Impurity Absorption

scholarly journals Exploring the Dynamics of Bound Water in Nylon Polymers with Terahertz Spectroscopy

2019 ◽  
Author(s):  
Hiromichi Hoshina ◽  
Takuro Kanemura ◽  
Chiko Otani ◽  
Michael Ruggiero
Keyword(s):  
Polymer Films ◽  
Density Functional ◽  
Bound Water ◽  
Adsorbed Water ◽  
Nylon 6 ◽  
Bulk Water ◽  
Spectral Signature ◽  
Thz Spectroscopy ◽  
Absorption Bands ◽  
Water Desorption

<p>Terahertz (THz) spectroscopy was used to observe adsorbed water structure and dynamics within polymer films, ultimately providing a strong rationale for the observed rates of water desorption. The THz absorption spectra of nylon-6 films undergoes drastic changes during the hydration and drying process. Additionally, the structural change from g to a crystals, induced by the hydration, was observed by the characteristic band of a-nylon-6 at 6.5 THz. Importantly, the THz spectra of adsorbed water, as well as deuterated water, within in the nylon films were observed by the continuous measurement of a-nylon during dehydration. The differential spectra clearly show three absorption bands of water molecules named Peak I, II and III, which behaved differently between the H<sub>2</sub>O and D<sub>2</sub>O materials. The spectra were assigned using a combination of <i>ab initio</i> molecular dynamics simulations and solid-state density functional theory calculations, and were compared to previous spectral assignments of bulk water. The results show that the inclusion of H<sub>2</sub>O and D<sub>2</sub>O into polymer films results in a distinct set of spectral features that, while similar in frequencies to the dynamics of bulk water, represent significantly different motions owing to the unique chemical environment within the material. These results highlight the significant utility of using THz spectroscopy to study the hydration dynamics and spectral signature of bound water in this important class of materials. </p>

Moments of Impurity Absorption Bands in Solids

1966 ◽  
Vol 13 (1) ◽  
pp. 175-179 ◽  
Author(s):  
A. Gold ◽  
T. H. Keil
Keyword(s):  
Absorption Bands ◽  
Impurity Absorption

scholarly journals Exploring the Dynamics of Bound Water in Nylon Polymers with Terahertz Spectroscopy

2019 ◽  
Author(s):  
Hiromichi Hoshina ◽  
Takuro Kanemura ◽  
Chiko Otani ◽  
Michael Ruggiero
Keyword(s):  
Polymer Films ◽  
Density Functional ◽  
Bound Water ◽  
Adsorbed Water ◽  
Nylon 6 ◽  
Bulk Water ◽  
Spectral Signature ◽  
Thz Spectroscopy ◽  
Absorption Bands ◽  
Water Desorption

<p>Terahertz (THz) spectroscopy was used to observe adsorbed water structure and dynamics within polymer films, ultimately providing a strong rationale for the observed rates of water desorption. The THz absorption spectra of nylon-6 films undergoes drastic changes during the hydration and drying process. Additionally, the structural change from g to a crystals, induced by the hydration, was observed by the characteristic band of a-nylon-6 at 6.5 THz. Importantly, the THz spectra of adsorbed water, as well as deuterated water, within in the nylon films were observed by the continuous measurement of a-nylon during dehydration. The differential spectra clearly show three absorption bands of water molecules named Peak I, II and III, which behaved differently between the H<sub>2</sub>O and D<sub>2</sub>O materials. The spectra were assigned using a combination of <i>ab initio</i> molecular dynamics simulations and solid-state density functional theory calculations, and were compared to previous spectral assignments of bulk water. The results show that the inclusion of H<sub>2</sub>O and D<sub>2</sub>O into polymer films results in a distinct set of spectral features that, while similar in frequencies to the dynamics of bulk water, represent significantly different motions owing to the unique chemical environment within the material. These results highlight the significant utility of using THz spectroscopy to study the hydration dynamics and spectral signature of bound water in this important class of materials. </p>

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