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Author Iomdina, E. N.; Seliverstov, S.; Sianosyan, A.; Teplyakova, K.; Rusova, A.; Goltsman, G. url  doi
openurl 
  Title The prospects of using the radiation for the assessment of corneal and scleral hydration Type Abstract
  Year 2016 Publication Acta Ophthalmol. Abbreviated Journal Acta Ophthalmol.  
  Volume 94 Issue Pages  
  Keywords BWO, avalanche transit‐time diode, medicine, biology  
  Abstract Purpose

An adequate water balance (hydration extent) is one of the basic factors of normal eye function, including its external shells – the cornea and the sclera. THz systems creating images in reflected beams are likely to become ideal instruments of noninvasive testing of corneal and scleral hydration degree as THz radiation is highly sensitive to water content. The paper aims at studying the transmittance and reflectance spectra of the cornea and the sclera of rabbit and human eyes, as well as those of the whole rabbit eye, in the frequency range of 0.13–0.32 THz.

Methods

The experiments were carried out on 3 corneas and 3 rabbit scleras, 2 whole rabbit eyes, and 3 human healthy adult scleras using a specially developed THz system based on reliable and easy‐to‐use continuous wave sources: a backward‐wave oscillator and an avalanche transit‐time diode.

Results

The transmittance spectra of the cornea and the sclera and the dependence of the reflection coefficient of these tissues in THz range on water percentage content were determined. Comparison of the rabbit cornea hydrated from 73.2% to 76.3% concentration by mass demonstrated an approximately linear relationship between THz reflectivity and water concentration. The decrease of free water concentration by 1% leads to a drop of the reflectance coefficient by 13%. The parameters studied displayed noticeable differences between the sclera and the cornea of rabbits and between rabbit sclera and human sclera.

Conclusions

Preliminary results demonstrate that the proposed technique, based on continuous THz radiation, may be used to create a device for noninvasive testing of corneal and scleral hydration, which has good potential of wide‐scale practical application.

The work was supported by the Russian Foundation of Basic Research (grant No.15‐29‐03843)
 
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  ISSN 1755375X ISBN Medium  
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  Notes Approved no  
  Call Number Serial 1333  
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Author Gol’tsman, G. N. url  doi
openurl 
  Title Terahertz technology in Russia Type Conference Article
  Year 1994 Publication 24th European Microwave Conf. Abbreviated Journal 24th European Microwave Conf.  
  Volume 1 Issue Pages 113-121  
  Keywords BWO, HEB mixers  
  Abstract The presentation consider the parameters and operating peculiarities of unique microwave generators of the terahertz range which have been created in Russia – the backward wave oscillators – as well as certain devices based on these generators, such as high resolution. spectrometers and time-resolving spectrometers with picosecond temporal resolution. Most resent BWO-based studies are illustrated by a project devoted to superconductive hot-electron. bolometers which are of great independent value for the terahertz technology as high-sensitive picosecond detectors and low noise broad-band mixers.  
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  Area Expedition Conference 24th European Microwave Conference  
  Notes Approved no  
  Call Number Serial 1635  
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Author Aksaev, E. E.; Gershenzon, E.M.; Gol'tsman, G. N.; Mirskij, G. I.; Semenov, A. D. url  openurl
  Title Submillimetric spectrometer-relaxometer based on backward-wave tubes with picosecond time resolution Type Journal Article
  Year 1991 Publication Pribory i Tekhnika Eksperimenta Abbreviated Journal Pribory i Tekhnika Eksperimenta  
  Volume 34 Issue 2 Pages 125-131  
  Keywords BWO, applications  
  Abstract The high-sensitive automatic spectrometer-relaxometer based on backward-wave tubes in the range of 4÷0.25 mm was described permitting to study the response kinetics of sample under investigation in any point of this range with the resolution time of 10-11 s. The relaxation measurements were conducted using oscillation beats of two adequate tubes, the frequency of one of them was fixed, while that of the other one was changeable. The amplitude-frequency characteristic of the response under the conditions of synchronous reception was recorded at beat frequency variation from 107 to 1010 Hz. The high sensitivity was reached by decreasing the device recording band down to 100 Hz in the whole measuring range.  
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  ISSN 0032-8162 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1683  
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Author Gershenson, E. M.; Gol'tsman, G. N.; Elant'ev, A. I.; Kagane, M. L.; Multanovskii, V. V.; Ptitsina, N. G. url  openurl
  Title Use of submillimeter backward-wave tube spectroscopy in determination of the chemical nature and concentration of residual impurities in pure semiconductors Type Journal Article
  Year 1983 Publication Sov. Phys. Semicond. Abbreviated Journal Sov. Phys. Semicond.  
  Volume 17 Issue 8 Pages 908-913  
  Keywords BWO spectroscopy, pure semiconductors, residual impurities  
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  Notes Применение субмиллиметровой ЛОВ спектроскопии для определения химической природы и концентрации примесей в чистых полупроводниках Approved no  
  Call Number Serial 1714  
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Author Gershenzon, E. M.; Gol'tsman, G. N.; Ptitsina, N. G. url  openurl
  Title Submillimeter spectroscopy of semiconductors Type Journal Article
  Year 1973 Publication Sov. Phys. JETP Abbreviated Journal Sov. Phys. JETP  
  Volume 37 Issue 2 Pages 299-304  
  Keywords semiconductors, submillimeter spectroscopy, spectrometer, BWO, Ge, free excitons  
  Abstract The possibility is considered of carrying out submillimeter-wave spectral investigations of semiconductors by means of a high resolution spectrometer with backward-wave tubes. Results of a study of the excitation spectra of small impurities, D-(A +) centers and free excitons in germanium are presented.  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1735  
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