The Luminescence Properties of BaGd2(MoO4)4: Eu3+, Er3+, Yb3+ Phosphors

2010 ◽  
Vol 663-665 ◽  
pp. 137-140 ◽  
Author(s):  
Jia Yue Sun ◽  
Wei Hang Zhang ◽  
Yu Jing Lan ◽  
Hai Yan Du
Keyword(s):  
Red Light ◽  
Green Light ◽  
Green Emission ◽  
Infrared Light ◽  
Solid State Method ◽  
Light Excitation ◽  
Bright Green ◽  
State Method ◽  
Uv Excitation ◽  
Color Emission

Two-color emission phosphors BaGd2(MoO4)4: Eu3+, Er3+, Yb3+ have been synthesized by the high temperature solid-state method. The as-prepared BaGd2(MoO4)4: Eu3+, Er3+, Yb3+ phosphors can emit intense red light under 395 nm UV excitation, while it will show bright green light upon 980 nm infrared light excitation. It is found that the red emission peaks at 595 and 614 nm should be attributed to 5D0-7F1 and 5D0-7F2 transitions of Eu3+, respectively. The green emission peaks centered at 532 and 553 nm under 980 nm excitation, are attributed to Er3+ transitions from 4H11/2 -4I15/2 and 4S3/2-4I15/2, respectively.

scholarly journals Preparation and Up-Conversion Luminescence of Yb3+/Er3+/GZO Ceramics

2018 ◽  
Vol 20 (3) ◽  
pp. 15-19
Author(s):  
Guomin Li ◽  
Bing Wang ◽  
Rui Wang ◽  
Huiling Liu
Keyword(s):  
Red Light ◽  
Emission Spectra ◽  
Green Emission ◽  
Power Curve ◽  
X Ray Diffraction ◽  
Solid State Method ◽  
Green Is ◽  
Xrd Pattern ◽  
X Ray ◽  
State Method

Abstract Yb3+/Er3+/GZO ceramics have been synthesized with high temperature solid-state method. The phase and structure of the Yb3+/Er3+/GZO ceramics were characterized by X-ray diffraction (XRD). The XRD pattern that following ions Yb3+, Er3+ and Ga3+ were well doped into the ZnO lattice. Effi cient visible up-conversion (UC) red and green emission were observed under 980 nm excitation. The mechanism of the UC luminescence is investigated on the basis of the UC luminescence emission spectra, the power curve and energy level diagram. The infl uence of doping ions to the intensity ratio of red to green is analyzed and high purity of red light (red/green = 29.9) is fi nally obtained.

scholarly journals Green Phosphors Based on 9,10-bis((4-((3,7-dimethyloctyl)oxy) phenyl) ethynyl) Anthracene for LED

Micromachines ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 703
Author(s):  
Xuefeng Ren ◽  
Hai Song ◽  
Jing Xiao ◽  
Hui-Juan Yu ◽  
Chi-Fang Peng ◽  
...  
Keyword(s):  
Blue Light ◽  
Light Emitting Diode ◽  
Visible Region ◽  
Green Light ◽  
Green Emission ◽  
Coupling Reactions ◽  
Light Emitting ◽  
Good Thermal Stability ◽  
Light Excitation ◽  
Bright Green

An anthracene aromatic unit was introduced into the phenylethynyl structure by a rigid acetylene linkage at the C-9 and C-10 positions via Sonogashira coupling reactions, resulting in a planar and straight-backbone molecule (9,10-bis((4-((3,7-dimethyloctyl)oxy) phenyl) ethynyl) anthracene) (BPEA). Thermogravimetric analysis demonstrated the good thermal stability of the BPEA. Photoluminescence analysis showed that a suitable expanded π-conjugation in the BPEA made its excitation band extend into the visible region, and an intense green emission was observed under blue-light excitation. A bright green light-emitting diode with an efficiency of 18.22 lm/w was fabricated by coating the organic phosphor onto a 460 nm-emitting InGaN chip. All the results indicate that BPEA is a useful green-emitting material which is efficiently excited by blue light, and therefore, that it could be applied in many fields without UV radiation.

scholarly journals Bright green emission from f-MWCNT embedded co-doped Bi3+ + Tb3+:polyvinyl alcohol polymer nanocomposites for photonic applications

RSC Advances ◽  
2017 ◽  
Vol 7 (25) ◽  
pp. 15084-15095 ◽  
Author(s):  
K. Naveen Kumar ◽  
R. Padma ◽  
Y. C. Ratnakaram ◽  
Misook Kang
Keyword(s):  
Carbon Nanotube ◽  
Polyvinyl Alcohol ◽  
Polymer Nanocomposites ◽  
Green Emission ◽  
Multi Walled Carbon Nanotube ◽  
Bright Green ◽  
Uv Excitation ◽  
Co Doped

A bright, dazzling green emission has been obtained from functionalized multi walled carbon nanotube (f-MWCNT)-embedded Bi3+ + Tb3+:PVA polymer nanocomposites under UV excitation.

scholarly journals Green emission carbon quantum dots from lemon juice for selective detection of Fe3+ ions

2019 ◽  
Vol 35 (1) ◽  
Author(s):  
Vuong Pham Hung
Keyword(s):  
Quantum Dots ◽  
Green Light ◽  
Green Emission ◽  
Carbon Quantum Dots ◽  
Lemon Juice ◽  
X Ray Diffraction ◽  
High Resolution Tem ◽  
Sensitivity And Selectivity ◽  
Bright Green ◽  
Xrd Techniques

        In this article carbon quantum dots (Cdots) were prepared by a facile, green, economical hydrothermal method of the mixed deionized water and lemon juice. Optical and structural properties of the Cdots have been extensively studied by UV–visible and fluorescence spectroscopy, x-ray diffraction (XRD) techniques, and high resolution TEM (HR-TEM). Surface functionality of Cdots has been illustrated by Fourier transform infrared spectroscopy (FTIR). The fabricated Cdots emit bright green light with broad spectrum. The Cdots exhibit captivating sensitivity and selectivity toward Fe3+ with a linear range from 0 to 80 ppm and a detection limit of 38.08 ppm.

scholarly journals Accuracy of the GENEActiv Device for Measuring Light Exposure in Sleep and Circadian Research

2020 ◽  
Vol 2 (2) ◽  
pp. 143-152
Author(s):  
Julia E. Stone ◽  
Elise M. McGlashan ◽  
Elise R. Facer-Childs ◽  
Sean W. Cain ◽  
Andrew J. K. Phillips
Keyword(s):  
Light Source ◽  
Light Exposure ◽  
Red Light ◽  
Spectral Composition ◽  
Green Light ◽  
Well Being ◽  
Infrared Light ◽  
Light Sources ◽  
Lower Accuracy ◽  
The Impact

Light is a variable of key interest in circadian rhythms research, commonly measured using wrist-worn sensors. The GENEActiv Original is a cost-effective and practical option for assessing light in ambulatory settings. With increasing research on health and well-being incorporating sleep and circadian factors, the validity of wearable devices for assessing light environments needs to be evaluated. In this study, we tested the accuracy of the GENEActiv Original devices (n = 10) for recording light under a range of ecologically relevant lighting conditions, including LED, fluorescent, infrared, and outdoor lighting. The GENEActiv output had a strong linear relationship with photopic illuminance. However, the devices consistently under-reported photopic illuminance, especially below 100 lux. Accuracy below 100 lux depended on the light source, with lower accuracy and higher variability under fluorescent lighting. The device’s accuracy was also tested using light sources of varying spectral composition, which indicated that the device tends to under-report photopic illuminance for green light sources and over-report for red light sources. Furthermore, measures of photopic illuminance were impacted by infrared light exposure. We conclude that the GENEActiv Original is suitable for mapping light patterns within an individual context, and can reasonably differentiate indoor vs. outdoor lighting, though the accuracy is variable at low light conditions. Given the human circadian system’s high sensitivity to light levels below 100 lux, if using the GENEActiv Original, we recommend also collecting light source data to better understand the impact on the circadian system, especially where participants spend prolonged periods in dim lighting.

scholarly journals Effect of Rb+ Doping on Tunable Luminescence in Yb3+/Er3+–Y2O3 Film

Coatings ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1137
Author(s):  
Boxu Xu ◽  
Chao Song ◽  
Jun Song ◽  
Rui Huang ◽  
Juncheng Liu ◽  
...  
Keyword(s):  
Sol Gel ◽  
Red Light ◽  
Green Light ◽  
Emission Spectra ◽  
Green Emission ◽  
X Ray Diffraction ◽  
Ion Distribution ◽  
Stark Level ◽  
Color Tunable ◽  
Tunable Emission

In this paper, a series of Rb+-doped Er3+/Yb3+–Y2O3 films were synthesized via a sol-gel method and spin coating. The structure and morphology of the samples were investigated by X-ray diffraction and scanning electron microscopy. The Rb+-doped films with nanoparticles, in the size range of 20–40 nm, were obtained. The spectroscopic analysis of the samples was investigated by using the emission spectra and the intensity of luminescence. All the samples exhibited a green emission ascribed to 2H11/2/4S3/2 to 4I15/2 of Er3+ and a red one ascribed to 4F9/2 and its stark level to 4I15/2 of Er3+. As the Rb+ concentration increased, the intensities of the green light and red light were enhanced 16.97- and 5.81-fold relative to that of the undoped sample. Moreover, by controlling the Rb+ concentration, the samples were capable of generating color-tunable luminescence from red to green linearly. The tunable emission was caused by the change of ion distribution ratio in 4F7/2(Er) and 4F9/2(Er) levels. The results suggest that the as-prepared Rb+-doped Er3+/Yb3+–Y2O3 films have a great potential for applications of luminescence.

Perancangan Sistem Kontrol Lampu Lalulintas Cerdas Dengan Menggunakan Mikrokontroler dan Kamera

Jurnal MIPA ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 200
Author(s):  
Tjerie Pangemanan ◽  
Arnold Rondonuwu
Keyword(s):  
Real Time ◽  
Digital Image ◽  
Red Light ◽  
Green Light ◽  
Processing Method ◽  
Traffic Lights ◽  
Traffic System ◽  
Road Users ◽  
Adjustment System ◽  
System Time

Masalah lalu lintas  merupakan salah satu  masalah yang sangat sulit diatasi dengan hanya menggunakan system waktu (timer). Oleh sebab itu diperlukan suatu system pengaturan otomatis yang bersifat real-time sehingga waktu pengaturan lampu lalu lintas dapat disesuaikan dnegan keadaan di lapangan. Penelitian ini bertujuan mengembangkan suatu simulasi sistem yang mampu mengestimasi panjang antrian kendaraan menggunakan metoda pengolahan citra digital hanya dengan menggunakan satu kamera untuk dijadikan parameter masukan  dalam menghitung lama waktu nyala lampu merah dan lampu hijau. Oleh karena itu, sistem lalulintas sangatlah diperlukan, sebagai sarana dan prasarana untuk menjadikan lalulintas lancar, aman, bahkan sebagai media pembelajaran disiplin bagi masyarakat pengguna jalan raya. Penelitian ini penulis menggunakan sistem pengontrolan berbasis citra digital dimana camera sebagai sensor. Untuk aplikasi dari  semua metode dalam penelitian ini digunakan Microcontroller AurdinoTraffic problems is one of the problems that is very difficult to overcome by only using the system time (timer). Therefore we need an automatic real-time adjustment system so that the time settings for traffic lights can be adjusted according to the conditions on the ground. This study aims to develop a system simulation that is able to estimate the length of the vehicle queue using a digital image processing method using only one camera to be used as input parameters in calculating the length of time the red light and green light. Therefore, the traffic system is very necessary, as a means and infrastructure to make traffic smooth, safe, even as a medium for disciplined learning for road users. In this study the authors used a digital image-based control system where the camera as a sensor. For the application of all methods in this study, Aurdino Microcontroller is used

scholarly journals More superior pyroelectric performance of synthesized dravite by high-pressure solid-state method

AIP Advances ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 035304
Author(s):  
You Shan ◽  
Guojun Zhou ◽  
Kairen Chen ◽  
Changchun Zhao ◽  
Kun Shen ◽  
...  
Keyword(s):  
High Pressure ◽  
Solid State ◽  
Solid State Method ◽  
State Method

scholarly journals Modeling Energy LED Light Consumption Based on an Artificial Intelligent Method Applied to Closed Plant Production System

2021 ◽  
Vol 11 (6) ◽  
pp. 2735
Author(s):  
Ernesto Olvera-Gonzalez ◽  
Martín Montes Rivera ◽  
Nivia Escalante-Garcia ◽  
Eduardo Flores-Gallegos
Keyword(s):  
Energy Consumption ◽  
Energy Savings ◽  
Nonlinear Models ◽  
Light Emitting Diode ◽  
Red Light ◽  
Green Light ◽  
Plant Production ◽  
Production Plant ◽  
Light Component ◽  
Gp Model

Artificial lighting is a key factor in Closed Production Plant Systems (CPPS). A significant light-emitting diode (LED) technology attribute is the emission of different wavelengths, called light recipes. Light recipes are typically configured in continuous mode, but can also be configured in pulsed mode to save energy. We propose two nonlinear models, i.e., genetic programing (GP) and feedforward artificial neural networks (FNNs) to predict energy consumption in CPPS. The generated models use the following input variables: intensity, red light component, blue light component, green light component, and white light component; and the following operation modes: continuous and pulsed light including pulsed frequency, and duty cycle as well energy consumption as output. A Spearman's correlation was applied to generate a model with only representative inputs. Two datasets were applied. The first (Test 1), with 5700 samples with similar input ranges, was used to train and evaluate, while the second (Test 2), included 160 total datapoints in different input ranges. The metrics that allowed a quantitative evaluation of the model's performance were MAPE, MSE, MAE, and SEE. Our implemented models achieved an accuracy of 96.1% for the GP model and 98.99% for the FNNs model. The models used in this proposal can be applied or programmed as part of the monitoring system for CPPS which prioritize energy efficiency. The nonlinear models provide a further analysis for energy savings due to the light recipe and operation light mode, i.e., pulsed and continuous on artificial LED lighting systems.

Sign in / Sign up

Export Citation Format

Share Document