Strongly enhanced luminescence of Sr4Al14O25:Mn4+phosphor by co-doping B3+and Na+ions with red emission for plant growth LEDs

(a) Emission spectrum of LEDs fabricated with 445 nm blue chip and Sr2Si5N8:Eu2+red phosphor. (b) Emission spectrum of LEDs fabricated with 445 nm blue chip and Sr4Al14O25:Mn4+phosphor. (c and d) Absorption spectrum of chlorophyll-b and chlorophyll-a.

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Structure identification and strongly enhanced luminescence of Sr9Y2(WO6)4: Mn4+ phosphors by co-doping Mg2+ ions for plant growth LEDs

Journal of Luminescence ◽

10.1016/j.jlumin.2020.117235 ◽

2020 ◽

Vol 223 ◽

pp. 117235 ◽

Cited By ~ 1

Author(s):

Faguang Zhou ◽

Miao Gao ◽

Yurong Shi ◽

Zhuowei Li ◽

Ge Zhu ◽

...

Keyword(s):

Plant Growth ◽

Structure Identification ◽

Co Doping ◽

Enhanced Luminescence

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Emission and absorption in the infra-red spectrum of mercury

Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character ◽

10.1098/rspa.1916.0045 ◽

1916 ◽

Vol 92 (645) ◽

pp. 608-620 ◽

Cited By ~ 3

Keyword(s):

Absorption Spectrum ◽

Emission Spectrum ◽

White Light ◽

Wave Length ◽

Mercury Vapour ◽

Red Emission ◽

Characteristic Absorption ◽

Additional Work ◽

Infra Red ◽

The Way

In a previous paper by McLennan and Dearle, it was pointed out that hands had been found in the absorption spectrum of non-luminous mercury vapour at λ = 1849 Å. U., λ = 2536·72 Å.U., and λ = 2338 Å.U., but that nothing had been done up to the present in the way of investigating the infra-red region of this spectrum for characteristic absorption hands. In the same paper an account was given of some measurements made on the infra-red emission spectrum of the mercury are for the purpose of establishing the wave-length and intensities of the lines in that region. The Present paper deals first with some additional work on the relative intensities of these lines, and, secondly, with the absorption hands produced by passing white light through non-luminous mercury vapour.

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Enhanced luminescence performance and efficiency of La2NaSbO6: Mn4+ by co-doping Ca2+ for plant growth lighting

Physica B Condensed Matter ◽

10.1016/j.physb.2021.413141 ◽

2021 ◽

pp. 413141

Author(s):

Jiajie Zhu ◽

Lin Sun ◽

Yi Zhang ◽

Linyan Fu ◽

Yingjie Zhu ◽

...

Keyword(s):

Plant Growth ◽

Co Doping ◽

Enhanced Luminescence ◽

Luminescence Performance

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Enhanced luminescence of a new red phosphor Na13Sr2Ta2(PO4)9:Eu3+ by co-doping charge compensators Li+/Na+/K+

Journal of Luminescence ◽

10.1016/j.jlumin.2019.116976 ◽

2020 ◽

Vol 220 ◽

pp. 116976 ◽

Cited By ~ 1

Author(s):

Ya-Nan Li ◽

Dan Zhao ◽

Lin-Ying Shi ◽

Shao-Jie Dai ◽

Yan-Ping Fan ◽

...

Keyword(s):

Red Phosphor ◽

Co Doping ◽

Enhanced Luminescence

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Numerical simulation and LEDs adaptation for grow lamp

Izvestiya Vysshikh Uchebnykh Zavedenii Materialy Elektronnoi Tekhniki = Materials of Electronics Engineering ◽

10.17073/1609-3577-2017-2-115-121 ◽

2019 ◽

Vol 20 (2) ◽

pp. 115-121

Author(s):

S. I. Supelnyak ◽

V. G. Kosushkin

Keyword(s):

Numerical Simulation ◽

Absorption Spectrum ◽

Solid State ◽

Plant Growth ◽

Emission Spectrum ◽

Solid State Lighting ◽

Lighting Technology ◽

Biometric Measurements

Solid−state lighting technology based on LEDs offers ample opportunities in plant lighting. This article presents a prototype of a solid−state lamp based on InGaN LEDs with radiation peaks of 440, 460, 530 and AlInGaP with radiation peaks at 590, 630 and 660 nm, equipped with a source of stabilized current and an optimized radiator. The emission spectrum of the LED illuminator is the result of numerical simulation using an experimentally obtained absorption spectrum of a leaf of a plant. The effect of using LEDs was compared to the effect of a sodium tubular lamp. Evaluation of the results of biometric measurements that were made throughout the experiment showed the possibility of the effect of the spectrum of the proposed LED illuminator on plant growth.

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Construction model for microalgae photometric cell

Monitoring systems of environment ◽

10.33075/2220-5861-2021-1-79-86 ◽

2021 ◽

pp. 79-86

Author(s):

A.S. Gulin ◽

◽

R.P. Trenkenshu ◽

Keyword(s):

Absorption Spectrum ◽

Emission Spectrum ◽

Absorption Spectra ◽

Red Light ◽

Wavelength Region ◽

High Sensitivity ◽

Transmitted Light ◽

Chlorophyll B ◽

Light Spectrum ◽

Speed Accuracy

The work assesses the efficiency of red light-emitting diodes widely used in phyto-irradiators. The article focuses on the emitting monochrome LED with an extended radiation range in a photometric cell used for determining the concentration of pigments in microalgae cultures, Spectrophotometric methods are known as the most accurate and relevant methods for assessing the concentration of pigments, having significant advantages for monitoring and controlling the process over chemical ones in terms of selectivity, speed, accuracy, sensitivity, substance consumption, as well as the possibility of continuous analysis in a flow. The study of the emission spectra of red LEDs, their comparison with the absorption spectra of microalgae cultures, as well as the selection of the most accessible emitting element for the photometric cell is carried out. The analysis of the absorption spectra of the culture and extracts of Dunaliella salina using the method of dividing the long-wavelength region of the spectrum (from 600 to 700 nm) into separate Gaussian curves is presented. Based on the results obtained, the choice of an LED is made, which has an extended radiation range and allows providing a high sensitivity of the device, with low price making it easy to manufacture a photometric cell. Comparison between the emission spectrum of the LED and the absorption spectrum of the microalgae culture allows us to conclude that the emission spectrum of the LED emitter is in good agreement with the maximum absorption spectrum of the chlorophyll b pigment in the 620–700 nm region, which means that such an emitter is capable of providing a higher energy efficiency. The spectrum of the transmitted light entering the photodetector is also built. It is concluded that the proposed LED, when used in a photometric cell, can effectively work with pigments in the red region of the spectrum. The obtained device spectra allow determining such culture characteristics as biomass and the ratio of chlorophyll a and chlorophyll b. The transmitted light spectrum allows determining not only the average value of the energy received by the photocell but also the amount of pigments.

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Silicon Stimulates Plant Growth and Metabolism in Rice Plants under Conventional and Osmotic Stress Conditions

Plants ◽

10.3390/plants10040777 ◽

2021 ◽

Vol 10 (4) ◽

pp. 777

Author(s):

Sara Monzerrat Ramírez-Olvera ◽

Libia Iris Trejo-Téllez ◽

Fernando Carlos Gómez-Merino ◽

Lucero del Mar Ruíz-Posadas ◽

Ernesto Gabriel Alcántar-González ◽

...

Keyword(s):

Plant Growth ◽

Osmotic Stress ◽

Abiotic Factors ◽

Stress Conditions ◽

Chlorophyll B ◽

Rice Seedlings ◽

Root Volume ◽

Total Sugars ◽

Dry Biomass ◽

Peg 8000

Exogenous silicon (Si) can enhance plant resistance to various abiotic factors causing osmotic stress. The objective of this research was to evaluate the application of 1 and 2 mM Si to plants under normal conditions and under osmotic stress. Morelos A-98 rice seedlings, were treated with 1 and 2 mM SiO2 for 28 d. Subsequently, half of the plants were subjected to osmotic stress with the addition of 10% polyethylene glycol (PEG) 8000; and continued with the addition of Si (0, 1 and 2 mM SiO2) for both conditions. The application of Si under both conditions increased chlorophyll b in leaves, root volume, as well as fresh and dry biomass of roots. Interestingly, the number of tillers, shoot fresh and dry biomass, shoot water content, concentration of total chlorophyll, chlorophyll a/b ratio, and the concentration of total sugars and proline in shoot increased with the addition of Si under osmotic stress conditions. The addition of Si under normal conditions decreased the concentration of sugars in the roots, K and Mn in roots, and increased the concentration of Fe and Zn in shoots. Therefore, Si can be used as a potent inorganic biostimulant in rice Morelos A-98 since it stimulates plant growth and modulates the concentration of vital biomolecules and essential nutrients.

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