Emissivity Measurement of Semitransparent Textiles

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
P. Bison ◽  
A. Bortolin ◽  
G. Cadelano ◽  
G. Ferrarini ◽  
E. Grinzato

In the textiles production industry it is more and more common to advertise new textiles, especially for sportswear, by claiming their ability to emit IR radiation in the long wave band at a higher degree with respect to normal clothes, that is highly beneficial to improve sporting performances. Three textiles are compared, one normal and two “special,” with Ag+ ions and carbon powder added, with different colors. The emissivity of the textiles has been measured to determine if it is increased in the “special” textiles with respect to the normal one. No substantial increase has been noticed. Nonetheless, the test implied some nonstandard procedures due to the semitransparent nature of the textiles, in comparison with the normal procedure that is commonly used on opaque surfaces.

2022 ◽  
Vol 962 (1) ◽  
pp. 012027
Author(s):  
A O Orlov ◽  
A A Gurulev ◽  
S V Tsyrenzhapov

Abstract A method of measuring transmittance of radiation from the film of ice 0 in the infrared wave band is described. Ice 0 is formed from supercooled water at the temperature below –23°C. This ice is ferroelectric and forms a highly conductive layer of the nanometric order of thickness at the boundary with dielectric. The complexity of the experiment consisted in the necessity of using low intensities of the probing signal and considering radiation of the cooled parts of the installation. In order to obtain a thin film of ice, the method of depositing water vapor on a substrate cooled in nitrogen was used. The method rules out formation of condensate in cooling. Deposition of water vapor is possible only in heating, when delivery of cold nitrogen vapor into the chamber with the sample is excluded. To ensure exposure of the film to IR radiation, two sources of infrared radiation were considered: a halogen lamp with a broad radiation spectrum (on the surface of heated glass) and a CO2 laser with the radiation wavelength of 10.6 µm. In the first case, spectral measurements are possible when filters are used. In the installation based on a CO2 laser, an intense signal is emitted, requiring consideration of sample heating. Components of the installation have been elaborated and investigated, on which transmittance of radiation from the film of ice 0 is planned to be measured.


2020 ◽  
Vol 976 ◽  
pp. 50-54
Author(s):  
Kai Feng Wu ◽  
Yue Zhou ◽  
Jing Ma ◽  
Juan Lin

With the requirement of the research on the stealthy aircraft’s infrared characteristic, the design and analysis have got more attention. Depend on synthesizing the main factors, include the surface IR radiation, the scatter radiation from the environment, the temperature distribution and the coat distribution of the surface, which effect the stealthy capability, a stealthy aircraft’s IR characteristic simulation model was proposed. Based on MODTRAN, the environment radiation model was built and was used in the simulation model. Finally, the proposed simulation mode was used in design and optimizing one stealthy aircraft, using combined the muti-island genetic algorithm with the sequential quadratic programming. The results of the mid-wave and long-wave radiation were got separately. These results provided considerable reference for infrared stealthy aircraft’s design.


1992 ◽  
Vol 47 (3) ◽  
pp. 471-474 ◽  
Author(s):  
A. Kawski ◽  
Z. Gryczynski ◽  
I. Gryczynski ◽  
J. Kuśba

a)Absorption transition moment directions of the diphenylphosphinyl (2 a) and methylsulphonyl (3 a) Absorption transition moment directions of the diphenylphosphinyl (2 and methylsulphonyl(3 a) co-substtuted in 4-dimethylamino-trans-styrenes were determined in stretched poylvinyl alcohol(PVA) films based on measurements of the absorption anisotropics. It has been found that thelong-wave absorption spectrum consists of two bands corresponding to differently directed transitionmoments. The transition moment of the intensive long-wave *La band is lies along the long axisof these molecules whereas that of the short-wave band is oriented at (p = 38° for 2 a and q> = 35°for 3 a relative to the transition moment direction of the 1La band-substtuted in 4-dimethylamino-trans-styrenes were determined in stretched poylvinyl alcohol (PVA) films based on measurements of the absorption anisotropics. It has been found that the long-wave absorption spectrum consists of two bands corresponding to differently directed transition moments. The transition moment of the intensive long-wave *La band is lies along the long axis of these molecules whereas that of the short-wave band is oriented at (p = 38° for 2 a and q> = 35° for 3 a relative to the transition moment direction of the 1La band


1985 ◽  
Vol 63 (11) ◽  
pp. 3256-3257
Author(s):  
Piotr Milart ◽  
Tadeusz M. Krygowski

Substituent effect on the long wave band in uv/vis spectra of p-substituted N-(α-methylarylidene)-p-(N′,N′-dimethylamino)-anilines (X = CH3O, CH3, H, Cl, and NO2) measured in eight solvents follows well the Hammett equation. Solvent effect on this band depends well on ET only for Cl- and NO2-substituted species. Both these findings support the conclusion that the long-wave band is in fact intramolecular charge transfer form the basicity center [Formula: see text] towards substituents.


1974 ◽  
Vol 29 (7-8) ◽  
pp. 546-548 ◽  
Author(s):  
Gerhard Höhne ◽  
Freimut Marschner ◽  
Klaus Praefcke

The photoelectron spectroscopic investigation of the unconjugated spiroketone of 1,3-oxathiol (1) shows that there is no significant interaction between the carbonyl group and the hetero-π-system, whereas in the UV-spectrum of this compound a long-wave band is measured, which can be assigned to an intramolecular charge-transfer and which causes the yellow colour of this aliphatic ketone.


2017 ◽  
Vol 84 (9) ◽  
Author(s):  
Pavel I. Galich ◽  
Stephan Rudykh

We analyze small amplitude shear waves (SWs) propagating in dielectric elastomer (DE) laminates subjected to finite deformations and electrostatic excitations. First, we derive long wave estimates for phase and group velocities of the shear waves propagating in any direction in DE laminates subjected to any homogenous deformation in the presence of an electric filed. To this end, we utilize a micromechanics-based energy potential for layered media with incompressible phases described by neo-Hookean ideal DE model. The long wave estimates reveal the significant influence of electric field on the shear wave propagation. However, there exists a configuration, for which electric field does not influence shear waves directly, and can only alter the shear waves through deformation. We study this specific configuration in detail, and derive an exact solution for the steady-state small amplitude waves propagating in the direction perpendicular to the finitely deformed DE layers subjected to electrostatic excitation. In agreement with the long wave estimate, the exact dispersion relation and the corresponding shear wave band gaps (SBGs)—forbidden frequency regions—are not influenced by electric field. However, SBGs in DE laminates with highly nonlinear electroelastic phases still can be manipulated by electric field through electrostatically induced deformation. In particular, SBGs in DE laminates with electroelastic Gent phases widen and shift toward higher frequencies under application of an electric field perpendicular to the layers. However, in laminates with neo-Hookean ideal DE phases, SBGs are not influenced either by electric field or by deformation. This is due to the competing mechanisms of two governing factors: changes in geometry and material properties induced by deformation. In this particular case, these two competing factors entirely cancel each other.


Author(s):  
Nadezhda A. Polyanskaya ◽  
Michael A. Ryabov ◽  
Pavel V. Strashnov ◽  
Roman V. Linko ◽  
Victor V. Davydov ◽  
...  

(Z)-10-(2-(4-amino-5-thioxo-4,5-dihydro-1H-1,2,4-triazole-3-il)hydrazono)-9-phenanthrone (I) was obtained by a condensation of 4-amino-5-hydrazino-4H-1,2,4-triazole-3-thiol with 9,10-phenanthrenequinone. The compound I was characterized by IR, UV-VIS, 1Н, 13С NMR and chromatography-mass spectrometry.  The electronic absorption spectra of I in aproton solvents (DMF, DMSO) are characterized by the existence of an intensive long-wave band in the range of 468 - 485 nm. The absorption maximum of a freshly prepared solution of I (485 nm) after 48 h gradually undergoes hypsochromic shift to 474 nm, and after 72 h it shifts to 468 nm. In the UV-VIS spectrum of I, at addition of NaOH the batochromic shift of a long wave band to 511 nm with a significant increase in intensity is observed. The presence of one isobestic point in the spectrum indicates the formation of a mono-anion. In the UV-VIS spectrum of I at addition of HCl solution, the long wave absorption band undergoes hypsochromic shift to 376 nm with a small decrease in intensity. In the 1Н NMR spectrum of I, in the range of 15.08 ppm a singlet signal of a proton of a hydrazo-group is observed. In the 13С NMR spectrum of I, in the range of 180.80 ppm a signal which corresponds to carbonyl C-atom is observed. Quantum chemical modeling of the electronic structure of I as well as its ionic forms was performed in the frames of the density functional theory approach (DFT) using of a hybride tri-parametric exchange Becke functional with a correlational Lee-Yang-Parr functional (B3LYP) and basis sets def2-SV(P), def2-TZV(P). According to the spectral and quantum chemical studies, in the crystalline state and saturated solution the compound I exists in the form of the thione quinone hydrazone tautomer stabilized by intramolecular hydrogen bonds. The thione tautomer is 44 kJ/mol more stable than a thiol tautomer, the transition barrier is 135 kJ/mol. However, it is not possible to exclude possibility of transition of the thione form into the thiol one in the diluted solutions. Forcitation:Polyanskaya N.A., Ryabov M.A., Strashnov P.V., Linko R.V., Davydov V.V., Kobrakov K.I., Karavaeva E.B. synthesis, spectralandquantumchemicalresearchesof (Z)-10-(2-(4-amino-5-thioxo-4,5-dihydro-1H-1,2,4-triazole-3-il)hydrazono)-9-phenanthrone. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 1. P. 55-65


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