On The Hygienic Efficiency Of Lighting With Leds in Industrial Premises

2021 ◽  
pp. 11-18
Author(s):  
Olga E. Zheleznikova ◽  
Lyudmila V. Sinitsyna ◽  
Sergey N. Ageev ◽  
Ivan V. Blentsov
Keyword(s):  
Human Body ◽  
Research Work ◽  
Experimental Studies ◽  
Visual Performance ◽  
Light Environment ◽  
Practical Significance ◽  
Light Emitting ◽  
Fluorescent Lamps ◽  
Lighting Conditions ◽  
Negative Effect

The article is devoted to the description of experimental studies on the assessment of the hygienic efficiency of lighting conditions with light emitting diodes (LEDs) of the first and second generations when performing industrial work. In the course of the research work, an experimental lighting installation (ELI) was developed and installed, able to implement lighting options with LEDs and fluorescent lamps (FL). The state of the accommodative-muscular apparatus, the retina and the central link of the organ of vision was assessed; integral indicators of visual performance were studied. It was found that the illumination with LEDs does not have a negative effect on the organ of vision, the human body as a whole or indicators of visual performance. Changes in the functional indicators of the organ of vision occurring during the performance of visual work are within the corresponding boundaries of physiological fluctuations and are reversible. It was revealed that second generation LEDs create a more favourable light environment for performing visual work of a production nature. The practical significance of the results obtained was shown.

The effectiveness of light-emitting diode lighting for providing circadian stimulus in office spaces while minimizing energy use

2019 ◽  
Vol 52 (2) ◽  
pp. 167-188 ◽  
Author(s):  
C Jarboe ◽  
J Snyder ◽  
MG Figueiro
Keyword(s):  
Energy Use ◽  
Spectral Power ◽  
Light Emitting Diode ◽  
Visual Performance ◽  
Luminous Intensity ◽  
Light Emitting ◽  
Lighting Conditions ◽  
Office Space ◽  
Discomfort Glare ◽  
Architectural Lighting

Architectural lighting has traditionally addressed visual performance and horizontal illuminance on the work plane, later focussing on energy efficiency, while only recently paying particular regard to human health outcomes. The present study evaluated the effectiveness of several light-emitting diode lighting strategies for delivering circadian stimulus to occupants of a typical office space while minimizing energy use. The study employed photometric simulations in a typical open-office space, delivering a criterion circadian stimulus of 0.3 to calculation points modelled at the simulated occupants’ eye level. Six luminaire types, two luminous intensity distributions, six spectral power distributions and two horizontal illuminances were evaluated, resulting in 144 unique lighting conditions. Additionally, the study calculated the discomfort glare for selected luminaires with the highest total lumen output, smallest aperture and direct-only luminous intensity distributions at the higher of the two horizontal illuminances (500 lx). The most impactful strategy involved supplementing common overhead lighting with a desktop luminaire delivering light directly to the simulated office occupants’ eyes, which provided greater circadian stimulus and used less energy than overhead luminaires that were capable of delivering the criterion circadian stimulus of 0.3.

Research Into Irradiation Conditions With Led Phyto-Irradiators in Cucumber Plants Cultivating by Photoculture Technology

2021 ◽  
pp. 56-61
Author(s):  
Alexander E. Kurshev ◽  
Sergey D. Bogatyrev ◽  
Olga E. Zheleznikova ◽  
Kirill A. Chmil
Keyword(s):  
Light Emitting Diode ◽  
Methodological Approach ◽  
Experimental Studies ◽  
Point Of View ◽  
Practical Significance ◽  
State University ◽  
Light Emitting ◽  
White Leds ◽  
Biochemical Processes ◽  
Growing Seasons

The article presents the results of two full vegetation growing seasons for Svyatogor F1 cucumber plants sort in photoculture conditions. The studies were carried out on an experimental research hydroponic installation (ERHI) under photosynthetically active photon irradiance EPPFD = (250 ± 10) μmol/s·m2. In the experiment, we used phyto-irradiators (PI) with high-pressure sodium lamps (HPSL) of the DNaZ type, as well as light emitting diode (LED) phyto-irradiators of the combined spectrum. A methodological approach to photobiological research (PBR) in the artificial climate laboratory at the Ogarev Mordovia State University was developed, which allowed us to determine the effect of the radiation of the LED PI combined spectrum on the productivity of cucumber plants under photoculture conditions. On the basis of the conducted experimental studies, it was found that the quality of seedlings grown under a phyto-irradiator with a HPSL of the DNaZ type is better than under a LED PI of the combined spectrum. From the point of view of the productivity of cucumber plants of this variety, the spectrum created by the radiation of white LEDs and radiation of LEDs with peak wavelengths λ = 660 nm and λ = 730 nm turned out to be more favourable. It was revealed that radiation, acting on the photoreceptors of a plant and thus triggering cascades of physiological and biochemical processes, can cause its ambiguous reaction. The practical significance of the results obtained was shown.

scholarly journals MODERN CONCEPTS ABOUT IMPACT OF DIFFERENT FOOD ADDITIVES ON THE HUMAN BODY

2021 ◽  
Vol 21 (1) ◽  
pp. 194-198
Author(s):  
Н. M. Mustafina ◽  
I. I. Starchenko ◽  
V. М. Koka ◽  
Ye. I. Lukachina ◽  
V. V. Chernyak
Keyword(s):  
Human Body ◽  
Negative Impact ◽  
Monosodium Glutamate ◽  
Food Additives ◽  
Experimental Studies ◽  
The Elderly ◽  
Malignant Tumours ◽  
Internal Organs ◽  
Negative Effect ◽  
The Impact

This article highlights the analysis of available data about the impact of food additives on a human body. We specified the meaning of the term "food additives", paid attention to the history of discovering and applying food additives, described the differences between natural and synthetic food additives. According to the literature, most food additives used in modern food industry can be considered quite safe. The safety of food additives is determined on the basis of extensive comparative studies, and the use of food additives is prohibited unless they have been tested and approved by the relevant authorities. But, with the development of analytical methods, the emergence of new experimental data, the question of the possible negative impacts of one or another additive on individual organs and systems of the human body can be reconsidered. In particular, certain food additives that were previously considered harmless, for example E 240, E 121, are now recognized as very dangerous and prohibited for use. It has been proven that food supplements that are harmless to one person can have a negative effect on another. Therefore, it is recommended to limit the use of food additives for children, the elderly and people prone to allergic reactions. The article describes in detail the results of experimental studies about the negative impact of specific additives, in particular ponceau 4R, sodium nitrite and monosodium glutamate on individual internal organs. Attention is focused on the group of food additives such as nitrogen compounds, which due to the biotransformation can result in the nitrite formation. An excess of the latter, in turn, according to some researchers, can provoke the development of malignant tumours in various organs, primarily in the terminal parts of the colon. Thus, the impact of various combinations of food additives on the morpho-functional state of the internal organs requires further detailed research.

Superior Stable and High Quantum Yield Phosphor Na2BaSr(PO4)2: Eu2+ for Plant Growth LEDs

2021 ◽  
Author(s):  
Jinmeng Xiang ◽  
Xiaoqi Zhao ◽  
Hao Suo ◽  
Minkun Jin ◽  
Xue Zhou ◽  
...  
Keyword(s):  
Quantum Yield ◽  
Plant Growth ◽  
Light Emitting Diodes ◽  
Light Environment ◽  
High Quantum Yield ◽  
Light Emitting ◽  
Growth Rhythm ◽  
High Quantum ◽  
Violet Light ◽  
Important Means

Controlling the light environment of plant growth using phosphor-converted light-emitting diodes (pc-LEDs) is an important means to regulate the growth rhythm and enhance the yield, in which bluish violet light...

scholarly journals Combined effect of mineralogical and chemical parameters on swelling behaviour of expansive soils

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Bendadi Hanumantha Rao ◽  
Peddireddy Sreekanth Reddy ◽  
Bijayananda Mohanty ◽  
Krishna R. Reddy
Keyword(s):  
Expansive Soils ◽  
Research Work ◽  
Swelling Pressure ◽  
Combined Effect ◽  
Practical Significance ◽  
Chemical Compositions ◽  
Chemical Parameters ◽  
Swelling Behaviour ◽  
Mineral Contents ◽  
Swelling Properties

AbstractMicrolevel properties such as mineralogical and chemical compositions greatly control the macro behaviour of expansive soils. In this paper, the combined effect of mineral (i.e. montmorillonite, MMC) and chemical contents (i.e. Ca and Na in their total (T), leachable (L) and exchangeable form (CEC)) on swelling behaviour is investigated in a comprehensive way. Several 3-dimensional (3D) graphs correlating MMC and Ca/Na ratio, together, with swelling property (swelling potential, Sa, and swelling pressure, Sp) are developed. 3D plots, in general, portrayed a non-linear relationship of Sa and Sp with MMC and Ca/Na ratio, together. It is hypothesized that swelling initially is triggered by chemical parameters due to their quick and rapid ionization capability, but the overall swelling phenomenon is largely controlled by MMC. It is importantly found that expansive soils are dominant with divalent Ca++ ions up to MMC of 67% and beyond this percentage, monovalent Na+ ions are prevalent. From the interpretation of results, the maximum Sa of 18% and Sp of 93 kPa is measured at MMC of 43%, (Ca/Na)T of 10–14 and (Ca/Na)L of 2–7. It is concluded from study that total CEC + MMC for determining Sa and (Ca/Na)T + MMC for determining Sp are superior parameters to be considered. The findings of the study also excellently endorsed the results of Foster32, who stated that ionization of Na or Ca depends on the constituent mineral contents. The findings presented herein are unique, interesting and bear very practical significance, as no earlier research work reported such findings by accounting for chemical and mineralogical parameters impact, in tandem, on swelling properties.

scholarly journals LEGIBILITY OF URBAN HIGHWAY TRAFFIC SIGNS USING NEW RETROREFLECTIVE MATERIALS

Transport ◽  
2010 ◽  
Vol 25 (3) ◽  
pp. 229-236 ◽  
Author(s):  
John D. Bullough ◽  
Nicholas P. Skinner ◽  
Conan P. O’Rourke
Keyword(s):  
Urban Area ◽  
Performance Model ◽  
Visual Performance ◽  
Practical Significance ◽  
Department Of Transportation ◽  
Highway Traffic ◽  
Traffic Signs ◽  
Photometric Measurements ◽  
Highway Signs

Unlighted highway signs, which use newly developed retroreflective materials, were installed along the major expressway in an urban area by the local department of transportation. Photometric measurements of the signs were used to assess their legibility applying the relative visual performance model, in comparison to lighted signs, con‐ forming to recommended illumination practices. The calculated visibility of the measured unlighted signs was similar to that of the signs equipped with exterior sign illumination. The practical significance and limitations of the relative visual performance approach are discussed.

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