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 Penyuluhan Alat Deteksi Kesadahan Dalam Air Berbasis Light Dependent Resistor Di Kelurahan Giritontro, Kecamatan Giritontro, Kabupaten Wonogiri

2018 ◽  
Vol 2 (2) ◽  
pp. 95-99
Author(s):  
Sumarna Sumarna ◽  
Dyah Kurniawati Agustikasa ◽  
Agus Purwanto ◽  
Nur Kadarisman ◽  
Anggiyani Ratnaningtyas Eka Nugraheni ◽  
...  
Keyword(s):  
Kidney Disease ◽  
Community Service ◽  
Detection System ◽  
Light Emitting Diode ◽  
Water Hardness ◽  
Natural Sciences ◽  
State University ◽  
Light Emitting ◽  
Light Passing ◽  
Service Activity

Beberapa daerah di Wonogiri memiliki tanah yang mengandung kapur, sementara itu sebagian masyarakat mengonsumsi air yang berasal dari dalam tanah. Pada kegiatan pengabdian kepada masyarakat tahun 2016 ditemukan permasalahan dalam masyarakat di kelurahan Wonogiri yaitu sulitnya mendeteksi adanya kapur dalam air yang mereka konsumsi. Sebagai akibatnya banyak masyarakat yang menderita penyakit dalam yang diakibatkan pengendapan kapur di dalam tubuh mereka seperti penyakit ginjal. Oleh karenanya, tim PPM Fakultas MIPA Universitas Negeri Yogyakarta membangun sistem pendeteksi adanya kapur dalam cairan berbasis Light Emitting Diode (LED) dan Light Dependent Resistor (LDR). LED digunakan untuk menyinari cairan dengan kadar kapur yang berbeda-beda, kemudian LDR akan mendeteksi cahaya LED yang melewati cairan tersebut. Besar kecilnya nilai luaran LDR akan bergantung kadar kapur dalam cairan. Masyarakat sangat antusias dan mulai menggunakan alat ini untuk mendeteksi adanya kapur di air yang mereka konsumsi. Kata kunci: Kesadahan, LDR, LED Workshop On Detector of Water Hardness Based On Light Dependet Resistor In Giritontro Village, Giritontro District, Wonogiri RegencyAbstract           Some areas in Wonogiri contain hardness in its soil, while some people consume water that come from the soil. In community service activity in 2016, we found problems in the community in Giritontro, Wonogiri that is the difficulties to detect the hardness in the water that people consume. As a result, many people who suffer from internal diseases caused by the deposition of lime in their bodies such as kidney disease. Therefore, the PPM team of the Faculty of Mathematics and Natural Sciences of Yogyakarta State University built a hardness detection system in liquid based Light Emitting Diode (LED) and Light Dependent Resistor (LDR). LEDs are used to irradiate fluids with different lime levels, then LDR will detect the LED light passing through the liquid. The size of the LDR output value will depend on the lime content in the liquid. People are very enthusiastic and start using this tool to detect the presence of limestone in the water they consume. Keywords: Hardness, LDR, LED

Color Tuning of Biomass-Derived Carbon Nanodots by Reaction Temperature Toward White Light-Emitting Diodes

NANO ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. 2050159
Author(s):  
Yi Gong ◽  
Yanbing Han ◽  
Fang Zhang ◽  
Mingyue Zhai ◽  
Xing Chen ◽  
...  
Keyword(s):  
Reaction Temperature ◽  
White Light ◽  
Heating Temperature ◽  
Light Emitting Diode ◽  
Peak Position ◽  
Carbon Nanodots ◽  
One Pot ◽  
Light Emitting ◽  
White Leds ◽  
Band Emission

In this work, carbon nanodots (CNDs) were synthesized from extract of mango leaves. Sphere nanodots were formed rapidly by one-step microwave heating. The photoluminescence (PL) of the CNDs was found greatly dependent on the reaction temperature. The emission peak position of the CNDs changed from 550[Formula: see text]nm to 430[Formula: see text]nm when the heating temperature increased from 120[Formula: see text]C to 150[Formula: see text]C. Particularly, the CNDs synthesized at 130[Formula: see text]C showed multi-band emission at 411[Formula: see text]nm, 480[Formula: see text]nm and 530[Formula: see text]nm, providing emitting color from blue to yellow. Moreover, the free chlorophyll molecules in the solution added red fluorescence at 670[Formula: see text]nm, and the integrated emitting color of the CNDs solution was close to white. Coated on a commercial 365[Formula: see text]nm light-emitting diode (LED) chip, the CNDs showed greenish white light with CIE coordinates of (0.37, 0.44). This work provided a one-pot, rapid and green method to obtain multi-emissive CNDs toward white LEDs.

Discomfort glare caused by white LEDs having different spectral power distributions

2017 ◽  
Vol 50 (6) ◽  
pp. 921-936 ◽  
Author(s):  
WJ Huang ◽  
Y Yang ◽  
M Ronnier Luo
Keyword(s):  
White Light ◽  
Spectral Power ◽  
Light Emitting Diode ◽  
Light Emitting ◽  
White Leds ◽  
Significant Difference ◽  
Discomfort Glare ◽  
Led Lights ◽  
Green Leds

This paper describes an experiment to investigate discomfort glare caused by white light-emitting diode (LED) lights having different spectral power distributions. It included two groups: a ‘Metamerism’ group and a ‘correlated colour temperatures (CCT)’ group. In the former group, it was found that white lights at 7000 K constructed from different blue LEDs and the same red and green LEDs gave about the same glare perception. In the latter group, there was a significant difference in glare perception between white lights having different CCTs. Finally, glare models, including unified glare rating (UGR) and the newly derived QUGRspd, and mUGRspd models, were tested using the data from the experiment. All of them gave quite accurate predictions of the data.

Current Status of GaN-Based Solid-State Lighting

MRS Bulletin ◽  
2009 ◽  
Vol 34 (2) ◽  
pp. 101-107 ◽  
Author(s):  
Shuji Nakamura
Keyword(s):  
Continuous Improvement ◽  
Charge Separation ◽  
Energy Savings ◽  
Light Emitting Diode ◽  
Current Status ◽  
Light Emitting ◽  
White Leds ◽  
Semipolar Gan ◽  
Near Future ◽  
Nonpolar Gan

AbstractThe continuous improvement in luminous efficacy of “white” light-emitting-diode (LED) sources offers the potential of considerable energy savings in general lighting applications. Recent experiments at UCSB have demonstrated 117 lumens per watt (lm/W) in white LEDs, with further improvements expected in the near future. Considerable progress has also been achieved using nonpolar GaN, such as a-plane {1120} and m-plane {1100} GaN, or semipolar GaN substrates. Such devices avoid the deleterious effects of charge separation due to spontaneous and piezoelectric polarization inherent in most c-axis-oriented devices.

scholarly journals OXIGÊNIO NO CONTEXTO DA COVID-19: O QUE SABEMOS SOBRE A MOLÉCULA QUE RESPIRAMOS E O PAPEL CENTRAL DA QUÍMICA

Química Nova ◽  
2021 ◽  
Author(s):  
Bruna Cerqueira ◽  
Bruna Silva ◽  
Rafael Campos ◽  
Lourenço Santana ◽  
Wilson Lopes ◽  
...  
Keyword(s):  
Light Emitting Diode ◽  
Chemical Characterization ◽  
Point Of View ◽  
Oxygen Production ◽  
Oxygen Saturation Level ◽  
Light Emitting ◽  
Physical Chemical ◽  
Oxygen Cycle ◽  
Oxygen Concentrator

OXYGEN IN THE COVID-19 CONTEXT: WHAT WE KNOW ABOUT THE MOLECULE WE BREATHE AND THE CENTRAL ROLE OF CHEMISTRY. In this work, the role of chemistry in the coronavirus disease 2019 (COVID-19) pandemic is highlighted through the medical oxygen supply crises in Brazil, as an example of oxygen utility in health. Starting from oxygen chemical characterization, the oxygen cycle in nature is discussed to show how oxygen is formed through photosynthesis, followed by the description of the industrial oxygen production from atmospheric air, including physical-chemical aspects. The use of medical oxygen concentrator is presented and how this device works from the chemical point of view. Besides, the noninvasive and painless oximetry is described in terms of how oxygen saturation level in blood is measured using LED - light emitting diode.

Flexible quantum dot–PVA composites for white LEDs

2015 ◽  
Vol 3 (2) ◽  
pp. 257-264 ◽  
Author(s):  
Arzu Cosgun ◽  
Renli Fu ◽  
Weina Jiang ◽  
Jianhai Li ◽  
Jizhong Song ◽  
...  
Keyword(s):  
Quantum Dot ◽  
Blue Light ◽  
Light Emitting Diode ◽  
Low Cost ◽  
Red Emission ◽  
Light Emitting ◽  
White Leds

Integration of blue light-emitting diode (LED) chips with yellow phosphors has been the most practical way to achieve white lighting, but finding a low-cost alternative for Y3Al5O12:Ce3+ (YAG:Ce) phosphors, which are expensive and lack red emission, is still a great challenge.

High quantum efficiency Ce:(Lu,Y)3(Al,Sc)2Al3O12 transparent ceramics with excellent thermal stability for high-power white LEDs/LDs

2020 ◽  
Vol 8 (46) ◽  
pp. 16427-16435
Author(s):  
Yuelong Ma ◽  
Le Zhang ◽  
Tianyuan Zhou ◽  
Chen Hou ◽  
Jian Kang ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Quantum Efficiency ◽  
High Power ◽  
Light Emitting Diode ◽  
Transparent Ceramics ◽  
High Quantum Efficiency ◽  
Excellent Thermal Stability ◽  
Light Emitting ◽  
White Leds ◽  
High Quantum

Transparent ceramics (TCs) with high quantum efficiency and excellent thermal stability are essential for the applications in high-power remote excitation white light-emitting diode or laser diode (LED/LD) lighting devices as color convertors.

Synthesis and luminescence properties of (Lu0.95−xCe0.05)2Ca1+2xMg2Si3O12 silicate garnet phosphors and its applications

2016 ◽  
Vol 09 (03) ◽  
pp. 1650049
Author(s):  
Wei Xia ◽  
Xiyan Zhang ◽  
Liping Lu
Keyword(s):  
Light Emitting Diode ◽  
Red Light ◽  
Emission Spectra ◽  
Peak Wavelength ◽  
Excitation Peak ◽  
Light Emitting ◽  
White Leds ◽  
Reducing Atmosphere ◽  
Color Rendering ◽  
Silicate Garnet

Silicate garnet phosphors (Lu[Formula: see text]Ce[Formula: see text]Ca[Formula: see text]Mg2Si3O[Formula: see text] with [Formula: see text], 0.05, 0.1, and 0.15 were prepared by high-temperature solid-state reaction in a reducing atmosphere. The crystal structure, photoluminescence and luminescence of the phosphors were investigated. The optimum excitation peak wavelength of the phosphors ranged from 450[Formula: see text]nm to 490[Formula: see text]nm, matching the emission spectra of a blue light-emitting diode chip. The phosphors emit orange-red light after excitation that can be tuned from 589[Formula: see text]nm to 597[Formula: see text]nm by changing the concentration of calcium ions. In addition, their emission made them suitable for use in warm-white LEDs with a high-color rendering index.

A novel inequivalent double-site substituted red phosphor Li4AlSbO6:Mn4+ with high color purity: Structure, photoluminescence properties, and application in warm white LEDs

2021 ◽  
Author(s):  
Zhiyuan Li ◽  
Xuhui Zhang ◽  
Ji Wu ◽  
Rui Guo ◽  
Lan Luo ◽  
...  
Keyword(s):  
Rare Earth ◽  
Spectral Properties ◽  
Light Emitting Diode ◽  
Color Purity ◽  
Photoluminescence Properties ◽  
Red Phosphor ◽  
Light Emitting ◽  
White Leds ◽  
Red Phosphors ◽  
High Color Purity

Non-rare-earth Mn4+-doped oxide red phosphors received increasing attention in the white light-emitting diode (LED) field for their admirable chemical stability and spectral properties. Here, a new inequivalent double-site substituted Mn4+-doped...

scholarly journals Photoluminescence and thermal stability of yellow-emitting Pr3+ doped CaAl2O4 phosphors

2013 ◽  
Vol 03 (03) ◽  
pp. 1350022 ◽  
Author(s):  
Hua Zou ◽  
Dengfeng Peng ◽  
Zhenming Chu ◽  
Xusheng Wang ◽  
Yanxia Li ◽  
...  
Keyword(s):  
Sintering Temperature ◽  
Light Emitting Diode ◽  
Luminescent Properties ◽  
Blue Shift ◽  
Yellow Emission ◽  
Conventional Solid State Reaction ◽  
Quenching Temperature ◽  
Light Emitting ◽  
White Leds ◽  
Thermal Stability Of

Pr 3+-doped CaAl 2 O 4 phosphors with broad yellow emission were synthesized by conventional solid-state reaction in air and their structural and luminescent properties were investigated. A pure monoclinic structure can be obtained when the sintering temperature is 1400°C or above. With photoluminescence (PL) measurement, the excitation was observed at 450–500 nm, which covered the emission of the blue light-emitting diode (LED) chips. Emission of the phosphors showed a green band and a red band. So these phosphors showed great potential in application of warm white LEDs without reabsorption. Additionally, the optimal emission intensity was obtained when Pr doping level was at 0.2 mol%. Furthermore, the Pr -doped CaAl 2 O 4 phosphors have the higher quenching temperature. With an increase in temperature, the emission bands of Pr -doped CaAl 2 O 4 showed an abnormal blue-shift.

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