scholarly journals Influence of Fluoropolymer Film Modified With Nanoscale Photoluminophor on Growth and Development of Plants

2020 ◽  
Vol 8 ◽  
Author(s):  
Veronika V. Ivanyuk ◽  
Alexey V. Shkirin ◽  
Konstantin N. Belosludtsev ◽  
Mikhail V. Dubinin ◽  
Valeriy A. Kozlov ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Growth And Development ◽  
Optical Spectrum ◽  
Red Light ◽  
High Latitudes ◽  
Tomato Plants ◽  
Violet Light ◽  
Northern Latitudes ◽  
Plant Photosynthesis ◽  
Fluoropolymer Films

The red and blue ranges of the optical spectrum are most suitable for plant photosynthesis. Moreover, quanta of red light stimulate photosynthesis more than quanta of blue light. In northern latitudes, the average daily intensity of the red and blue parts of the spectrum is usually not sufficient for many plants. To increase the productivity of greenhouses in northern latitudes, a technology has been developed for fluoropolymer films with photoconversion nanoparticles (quantum dots) that convert UV radiation and violet light into red light. The use of photoconversion fluoropolymer films promotes an increase in the biomass of plants grown in greenhouses at high latitudes. The greatest effect is observed when tomato plants are grown under photoconversion fluoropolymer films. The biomass of tomato berry obtained from one bush grown under films is 20% higher than the biomass of berry of control tomato plants.

scholarly journals Photoconversion Fluoropolymer Films for the Cultivation of Agricultural Plants Under Conditions of Insufficient Insolation

2020 ◽  
Vol 10 (22) ◽  
pp. 8025
Author(s):  
Alexander V. Simakin ◽  
Veronika V. Ivanyuk ◽  
Alexey S. Dorokhov ◽  
Sergey V. Gudkov
Keyword(s):  
Quantum Dots ◽  
Visible Spectrum ◽  
Biomass Growth ◽  
High Latitudes ◽  
Great Demand ◽  
Agricultural Plants ◽  
Fluoropolymer Films ◽  
Violet Radiation

Plants are capable of using mainly the quanta of the red and blue parts of a spectrum for the reception of energy during photosynthesis. However, for many crops grown indoors in high latitudes or under conditions of insufficient insolation, the average daily intensity of the red and blue parts of the spectrum is usually sufficient only on clear summer days. A technology has been proposed to produce a photoconversion fluoropolymer film for greenhouses, which is based on the modification of fluoropolymer by nanoparticles with fluorescence in the blue or red part of the spectrum (quantum dots). The films are capable of converting UV and violet radiation into the blue and red region of the visible spectrum, the most important for plants. It has been shown that the use of photoconversion fluoropolymer films promotes biomass growth. The area of cucumber leaves grown under photoconversion films increases by 20%, pumpkins by 25%, pepper by 30%, and tomatoes by 55%. The use of photoconversion fluoropolymer films for greenhouses also allows obtaining 15% more fruit biomass from one bush. In general, the use of photoconversion fluoropolymer films may be in great demand for greenhouses lying in high latitudes and located in areas with insufficient insolation.

scholarly journals Red Light-Emitting Diodes with All-Inorganic CsPbI3/TOPO Composite Nanowires Color Conversion Films

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Lung-Chien Chen ◽  
Yi-Tsung Chang ◽  
Ching-Ho Tien ◽  
Yu-Chun Yeh ◽  
Zong-Liang Tseng ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Light Emitting Diode ◽  
Red Light ◽  
Trioctylphosphine Oxide ◽  
Optical And Electrical Properties ◽  
Colloidal Solutions ◽  
High Quality ◽  
Light Emitting ◽  
Hot Injection ◽  
Color Conversion

AbstractThis work presents a method for obtaining a color-converted red light source through a combination of a blue GaN light-emitting diode and a red fluorescent color conversion film of a perovskite CsPbI3/TOPO composite. High-quality CsPbI3 quantum dots (QDs) were prepared using the hot-injection method. The colloidal QD solutions were mixed with different ratios of trioctylphosphine oxide (TOPO) to form nanowires. The color conversion films prepared by the mixed ultraviolet resin and colloidal solutions were coated on blue LEDs. The optical and electrical properties of the devices were measured and analyzed at an injection current of 50 mA; it was observed that the strongest red light intensity was 93.1 cd/m2 and the external quantum efficiency was 5.7% at a wavelength of approximately 708 nm when CsPbI3/TOPO was 1:0.35.

Near‐Unity Quantum Yield and Superior Stable Indium‐Doped CsPbBr x I 3− x Perovskite Quantum Dots for Pure Red Light‐Emitting Diodes

2021 ◽  
pp. 2101517
Author(s):  
Xin Zhou ◽  
Jibin Zhang ◽  
Xuan Tong ◽  
Yabing Sun ◽  
Haiyan Zhang ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Quantum Yield ◽  
Light Emitting Diodes ◽  
Red Light ◽  
Light Emitting ◽  
Perovskite Quantum Dots

scholarly journals Daily Variations of Photosynthetic Efficiency of Greenhouse Tomato Plants during Winter and Spring

2000 ◽  
Vol 125 (2) ◽  
pp. 235-241 ◽  
Author(s):  
O. Ayari ◽  
M. Dorais ◽  
A. Gosselin
Keyword(s):  
Photosynthetic Efficiency ◽  
Photosynthetic Activity ◽  
Photon Flux ◽  
Tomato Plants ◽  
Greenhouse Tomato ◽  
Northern Latitudes ◽  
Protective Strategy ◽  
Growing Conditions ◽  
Source Limitation

Daily and seasonal variations of photosynthetic activity, chlorophyll a (Chl-a) fluorescence and foliar carbohydrate content were studied in situ on greenhouse tomato (Lycopersicon esculentum Mill. `Trust') plants grown under CO2 enrichment and supplemental lighting. The objective of this study was to assess the effect of seasonal variation of the photosynthetic photon flux (PPF) on photosynthetic efficiency of tomato plants and to determine the presence or absence of photosynthetic down-regulation under greenhouse growing conditions prevailing in northern latitudes. During winter, the fifth and the tenth leaves of tomato plants showed low, constant daily photosynthetic activity suggesting a source limitation under low PPF. In winter, the ratio of variable to maximum Chl-a fluorescence in dark adapted state (Fv/Fm) remained constant during the day indicating no photoinhibition occurred. In February, an increase in photosynthetic activity was followed by a decline during March, April, and May accompanied by an increase in sucrose and daily starch concentrations and constant but high hexose level. This accumulation was a long-term response to high PPF and CO2 enrichment which would be caused by a sink limitation. Thus, in spring we observed an in situ downregulation of photosynthesis. The ratio Fv/Fm decreased in spring compared to winter in response to increasing PPF. The daily decline of Fv/Fm was observed particularly as a midday depression followed by a recovery towards the end of the day. This indicated that tomato leaves were subject to a reversible inhibition in spring. Fv/Fm was lower in March than in April and May even though PPF was higher in April and May than in March. These results suggest that tomato plants develop an adaptive and protective strategy as PPF increases in spring.

scholarly journals Identification and expression of the trehalose-6-phosphate synthase gene family members in tomato exposed to different light spectra

2017 ◽  
Vol 69 (1) ◽  
pp. 93-101
Author(s):  
Zexiong Chen ◽  
Juan Lou
Keyword(s):  
Plant Growth ◽  
Blue Light ◽  
White Light ◽  
Growth And Development ◽  
Light Quality ◽  
Red Light ◽  
Floral Transition ◽  
Stem Length ◽  
Pcr Analysis ◽  
Phosphate Synthase

Light is the source of energy for plants. Light wavelengths, densities and irradiation periods act as signals directing morphological and physiological characteristics during plant growth and development. To evaluate the effects of light wavelengths on tomato growth and development, Solanum lycopersicum (cv. micro-Tom) seedlings were exposed to different light-quality environments, including white light and red light supplemented with blue light (at ratios of 3:1 and 8;1, respectively). Tomatoes grown under red light supplemented with blue light displayed significantly shorter stem length, a higher number of flower buds and rate of fruit set, but an extremely late flowering compared to white-light-grown plants. To illustrate the mechanism underlying the inhibition of stem growth and floral transition mediated by red/blue light, 10 trehalose-6-phosphate synthase (TPS) genes were identified in tomato, and bioinformatics analysis was performed. qRT-PCR analysis showed that SlTPSs were expressed widely throughout plant development and SlTPS1 was expressed at extremely high levels in stems and buds. Further analysis of several flowering-associated genes and microRNAs showed that the expressions of SlTPS1, SlFT and miR172 were significantly downregulated in tomato grown under red and blue light compared with those grown under white light, whereas miR156 transcript levels were increased. A regulatory model underlying vegetative growth and floral transition regulated by light qualities is presented. Our data provide evidence that light quality strongly affects plant growth and phase transition, most likely via the TPS1-T6P signaling pathway.

scholarly journals Analyzing ozone variations and uncertainties at high latitudes during Sudden Stratospheric Warming events using MERRA-2

2021 ◽  
Author(s):  
Shima Bahramvash Shams ◽  
Von P. Walden ◽  
James W. Hannigan ◽  
William J. Randel ◽  
Irina V. Petropavlovskikh ◽  
...  
Keyword(s):  
Stratospheric Ozone ◽  
Polar Vortex ◽  
The Arctic ◽  
High Latitudes ◽  
Stratospheric Warming ◽  
Sudden Stratospheric Warming ◽  
Total Column Ozone ◽  
Northern Latitudes ◽  
Stratospheric Dynamics ◽  
Zonal Average

Abstract. Stratospheric circulation is a critical part of the Arctic ozone cycle. Sudden stratospheric warming events (SSWs) manifest the strongest alteration of stratospheric dynamics. Changes in planetary wave propagation vigorously influence zonal mean zonal wind, temperature, and tracer concentrations in the stratosphere over the high latitudes. In this study, we examine six major SSWs from 2004 to 2020 using the Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2). Using the unique density of observations around the Greenland sector at high latitudes, we perform comprehensive comparisons of high latitude observations with the MERRA-2 ozone dataset during the six major SSWs. Our results show that MERRA-2 captures the high variability of mid stratospheric ozone fluctuations during SSWs over high latitudes. However, larger uncertainties are observed in the lower stratosphere and troposphere. The zonally averaged stratospheric ozone shows a dramatic increase of 9–29 % in total column ozone (TCO) near the time of each SSW, which lasts up to two months. The SSWs exhibit a more significant impact on ozone over high northern latitudes when the polar vortex is mostly elongated as seen in 2009 and 2018 compared to the events in which the polar vortex is displaced towards Europe. The regional impact of SSWs over Greenland has a similar structure as the zonal average, however, exhibits more intense ozone anomalies which is reflected by 15–37 % increase in TCO. The influence of SSW on mid stratospheric ozone levels persists longer than their impact on temperature. This paper is focused on the increased (suppressed) wave activity before (after) the SSWs and their impact on ozone variability at high latitudes. This includes an investigation of the different terms of tracer continuity using MERRA-2 parameters, which emphasizes the key role of vertical advection on mid-stratospheric ozone during the SSWs.

In Situ Ligand Bonding Management of CsPbI 3 Perovskite Quantum Dots Enables High‐Performance Photovoltaics and Red Light‐Emitting Diodes

2020 ◽  
Vol 59 (49) ◽  
pp. 22230-22237 ◽  
Author(s):  
Junwei Shi ◽  
Fangchao Li ◽  
Yan Jin ◽  
Cheng Liu ◽  
Ben Cohen‐Kleinstein ◽  
...  
Keyword(s):  
Quantum Dots ◽  
High Performance ◽  
Light Emitting Diodes ◽  
Red Light ◽  
Light Emitting ◽  
Perovskite Quantum Dots

scholarly journals Influence of nitrogen availability on growth and development of tomato plants until fruit-setting

1993 ◽  
pp. 235-241 ◽  
Author(s):  
Y. Dumas ◽  
J. Suniaga Quijada ◽  
M. Bonafous
Keyword(s):  
Growth And Development ◽  
Nitrogen Availability ◽  
Tomato Plants ◽  
Fruit Setting
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