Exposure to Ultraviolet Radiation from Fluorescent Lamps

2021 ◽  
pp. 77-82
Author(s):  
M. Kemal Atesmen
Keyword(s):  
Ultraviolet Radiation ◽  
Fluorescent Lamps

Impact of damaging and recovery on the temperature dependence of the work function of oxide electrodes in fluorescent lamps

2021 ◽  
Vol 96 (1) ◽  
pp. 11301
Author(s):  
Reinhard Langer ◽  
Irina Paul ◽  
Reinhard Tidecks
Keyword(s):  
Ultraviolet Radiation ◽  
Temperature Dependence ◽  
Work Function ◽  
Surface States ◽  
Strong Increase ◽  
Thermal Excitation ◽  
Cold Starting ◽  
Fluorescent Lamps ◽  
Oxide Electrodes ◽  
Before And After

In the present work the work function of electrons for oxide cathodes in operating fluorescent lamps is measured before and after damaging the cathodes by cold starting of the lamp. A strong increase of the absolute value and a decrease of the temperature dependence of the work function is observed. The values recover partly after operating the lamp for a certain time. The results are interpreted as the consequence of a thin metallic layer generated during cold starting at the surface of the oxide and its effect on the depletion of electrons of donor-like colour centres (appearing in the oxide due to oxygen vacancies) under the ultraviolet radiation present in an operating fluorescent lamp, and on the magnitude and temperature dependence of the work function in the plated regions, invoking the patch effect to generate an averaged value of the work function, which is then assumed to be observed experimentally. Moreover, barium surface states are considered, yielding reasonable values for the not plated regions, when calculating the work function, as well for the assumption of a depletion of also these states by ultraviolet radiation, as also when only regarding a thermal excitation of the surface states applying the Fowler equation. Finally, a model of a diffusion governed dynamical equilibrium yielding a T3∕2 dependence for the donor concentration is proposed.

Ultraviolet radiation emitted by compact fluorescent lamps

MAPAN ◽  
2009 ◽  
Vol 24 (3) ◽  
pp. 183-191 ◽  
Author(s):  
Parag Sharma ◽  
V. K. Jaiswal ◽  
H. C. Kandpal
Keyword(s):  
Ultraviolet Radiation ◽  
Fluorescent Lamps ◽  
Compact Fluorescent Lamps

scholarly journals Comparison of Radiation Levels Emission Between Compact Fluorescent Lamps (CFLS) and Incandescent Bulbs

2015 ◽  
Vol 6 ◽  
pp. 124-128
Author(s):  
M I Ike- Ogbonna ◽  
D I Jwanbot ◽  
E E Ike
Keyword(s):  
Ultraviolet Radiation ◽  
Fluorescent Lamp ◽  
Radiation Emission ◽  
Fluorescent Lamps ◽  
Compact Fluorescent Lamps ◽  
Measurement And Analysis ◽  
Electric Light ◽  
Compact Fluorescent Lamp ◽  
Safety Limit

In this paper, the comparison of radiation levels emission between compact fluorescent lamps and incandescent bulbs were carried out with four (4) compact fluorescent lamps and four (4) incandescent bulbs using a Gamma scout (GS 20 model). The measurements were taken at varied distances of 20 to 100 cm. The readings for window 1, window 2 and window 3 were obtained in μSv/h. At distance of 20 cm, the emissions for the compact fluorescent lamp ranged from 7.10 μSv/h to 32.2 μSv/h for window 1, 6.70 μSv/h to 28.3 μSv/h for window 2 and 6.40 μSv/h to 26.1 μSv/h for window 3 and for the incandescent bulbs they ranged, from 2.50 μSv/h to 3.60 μSv/h for window 1, 2.50 μSv/h to 4.00 μSv/h for window 2 and 2.50 μSv/h to 3.80 μSv/h for window 3. The results of the measurement and analysis carried out revealed that, there were possible ultraviolet radiation emission from the electric light bulbs with higher radiation emission from compact fluorescent lamp when compared with those from incandescent bulbs. However the values were still found to be within the safety limit.

Ultraviolet radiation emissions from miniature (compact) fluorescent lamps

1990 ◽  
Vol 22 (2) ◽  
pp. 125-128 ◽  
Author(s):  
M.J. Whillock ◽  
A.F. McKinlay ◽  
J. Kemmler ◽  
P.G. Forsgren
Keyword(s):  
Ultraviolet Radiation ◽  
Fluorescent Lamps ◽  
Compact Fluorescent Lamps

Interlaboratory Evaluation of Ultraviolet Radiation Emissions from Compact Fluorescent Lamps

2016 ◽  
Vol 92 (2) ◽  
pp. 348-354 ◽  
Author(s):  
Sharon Miller ◽  
Rolf Bergman ◽  
Mark Duffy ◽  
David Gross ◽  
Andrew Jackson ◽  
...  
Keyword(s):  
Ultraviolet Radiation ◽  
Fluorescent Lamps ◽  
Compact Fluorescent Lamps

Applications of Photoelectron Microscopy

1976 ◽  
Vol 34 ◽  
pp. 506-507
Author(s):  
William J. Baxter
Keyword(s):  
Electron Microscopy ◽  
Thermal Decomposition ◽  
Chemical Composition ◽  
Ultraviolet Radiation ◽  
Thin Layer ◽  
Edge Effects ◽  
Electron Optics ◽  
Surface Layers ◽  
Crystalline Orientation ◽  
Fluorescent Screen

In this form of electron microscopy, photoelectrons emitted from a metal by ultraviolet radiation are accelerated and imaged onto a fluorescent screen by conventional electron optics. image contrast is determined by spatial variations in the intensity of the photoemission. The dominant source of contrast is due to changes in the photoelectric work function, between surfaces of different crystalline orientation, or different chemical composition. Topographical variations produce a relatively weak contrast due to shadowing and edge effects.Since the photoelectrons originate from the surface layers (e.g. ∼5-10 nm for metals), photoelectron microscopy is surface sensitive. Thus to see the microstructure of a metal the thin layer (∼3 nm) of surface oxide must be removed, either by ion bombardment or by thermal decomposition in the vacuum of the microscope.

803: Interactions Between Ultraviolet Radiation and Polymorphisms in the Vitamin D Receptor Gene Mediate Prostate Cancer Susceptibility

2006 ◽  
Vol 175 (4S) ◽  
pp. 260-260
Author(s):  
Nicholas J. Rukin ◽  
Samuel J. Moon ◽  
Dhaval Bodiwala ◽  
Christopher J. Luscombe ◽  
Mark F. Saxby ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Vitamin D ◽  
Ultraviolet Radiation ◽  
Vitamin D Receptor ◽  
Cancer Susceptibility ◽  
Receptor Gene ◽  
Vitamin D Receptor Gene ◽  
Prostate Cancer Susceptibility
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