Metal halide lamps: Gravitational influence on color separation

2006 ◽  
Vol 78 (6) ◽  
pp. 1239-1252 ◽  
Author(s):  
W. W. Stoffels ◽  
A. J. Flikweert ◽  
T. Nimalasuriya ◽  
J. J. A. M. van der Mullen ◽  
G. M. W. Kroesen ◽  
...  
Keyword(s):  
Large Scale ◽  
High Efficiency ◽  
Numerical Models ◽  
Metal Halide ◽  
Light Sources ◽  
Color Separation ◽  
Gravitational Influence ◽  
Metal Halide Lamps ◽  
And Diffusion ◽  
Diffusion Flows

Metal halide lamps are very efficient light sources based on a Hg plasma arc with metal halide salt additions. In spite of their high efficiency, the lamps suffer from several problems, such as color separation and instabilities, which currently hinder large-scale use. These phenomena are caused by a complex interaction of convection and diffusion flows in the plasma. In order to unravel the various contributions, experiments under microgravity have been performed where convection is absent. The experiments confirm the previously held qualitative views, but also provide absolute data on densities and temperatures that will be used to validate numerical models of these lamps.

Electrical consequences of large-scale replacement of metal halide by LED luminaires

2016 ◽  
Vol 50 (2) ◽  
pp. 282-293 ◽  
Author(s):  
MJ Hermoso-Orzáez ◽  
JI Rojas-Sola ◽  
A Gago-Calderón
Keyword(s):  
Large Scale ◽  
Thermal Protection ◽  
Metal Halide ◽  
Light Sources ◽  
Electrical Parameters ◽  
Large Power ◽  
Start Up ◽  
Before And After ◽  
Inrush Currents ◽  
Metal Halide Lamps

The recent trend for large-scale replacement of luminaires using discharge light sources with LED luminaires without any significant adjustments to the electrical installation has generated controversy. This study examines the main electrical measures in a large outdoor lighting installation before and after the replacement of a large number of metal halide floodlights with LED luminaires. The electrical parameters of both technologies are discussed in detail and compared, with special attention given to the odd-numbered harmonics of voltage and current, the generated wave deformation, currents in the neutral conductor, the wattless reactive volt amps and the peak inrush currents. At cold start-up, the LED luminaires generate large power-on currents, much larger than those generated by the metal halide lamps, despite requiring 36% less real installed power. This is a basic problem to be solved when planning a public lighting renovation with LED luminaires as the rest of electrical parameters are reduced. To address this problem, it is proposed to energise the luminaires using magneto-thermal protection circuits with slow trip curves that will tolerate the large short-term inrush currents.

Application of LED in Marine Fishery

2013 ◽  
Vol 765-767 ◽  
pp. 213-216
Author(s):  
Wen Qing Shi ◽  
Zheng Ye Xiong ◽  
Yong Qiang Li ◽  
Cun You Huang
Keyword(s):  
High Energy ◽  
Economic Benefits ◽  
Metal Halide ◽  
Light Sources ◽  
Market Demand ◽  
Led Light ◽  
Marine Fishery ◽  
Incandescent Lamps ◽  
Metal Halide Lamps ◽  
Chinese Marine

Aiming at the high energy-consuming characteristics of Chinese marine fishery, the application of LED in Chinese marine fishery is analyzed. It has remarkable energy-saving effect if the fishing style of trawling is replaced by light-seine fishing, and the gathering-fish lamps of metal halide lamps or incandescent lamps are replaced by LED light sources. The conversion of the trawlers to light-seine vessel and widespread use of LED light sources will lead to cut down energy consumption and increase the economic benefits. Based on rough calculation, it can make Chinese fisherfolk increase income about hundreds of millions of dollars and reduce more than millions of tons CO2 emission if the conversion of the trawlers to light-seine vessel and the replacement of metal halide lamps or incandescent lamps to LED light sources can reach 20% of all. Moreover, LED light source can use for general lighting purpose in marine fishery. All of these will cause the development of the correlative industries. For instance, the market demand of LED is very vast.

scholarly journals Effectiveness of Light Source on Detecting Thin Film Transistor

Crystals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 394 ◽  
Author(s):  
Fu-Ming Tzu ◽  
Jung-Hua Chou
Keyword(s):  
Thin Film ◽  
Light Source ◽  
Thin Film Transistor ◽  
Metal Halide ◽  
Light Sources ◽  
Blue Led ◽  
Optical Inspection ◽  
Metal Halide Lamps ◽  
Better Than ◽  
Halogen Lamps

Light sources tend to affect images captured in any automatic optical inspection (AOI) system. In this study, the effectiveness of metal-halide lamps, quartz-halogen lamps, and LEDs as the light sources in AOI systems for the detection of the third and fourth layers electrodes of thin-film-transistor liquid crystal displays (TFT-LCDs) is examined experimentally. The results show that the performance of LEDs is generally comparable or better than that of metal-halide and quartz-halogen lamps. The best optical performance is by the blue LED due to its spectrum compatibility with the time-delay-integration charged-coupled device (TDI CCD) sensor and its better spatial resolution. The images revealed by the blue LED are sharper and more distinctive. Since current LEDs are more energy efficient and environmentally friendly, using LEDs as the light source for AOI is very beneficial. As the blue LED performs the best, it should be adopted for AOI using TDI CCD sensors.

scholarly journals Effectiveness of Light Source on Detecting Thin Film Transistor

2018 ◽  
Author(s):  
Fuming Tzu ◽  
Jung-Hua Chou
Keyword(s):  
Thin Film ◽  
Light Source ◽  
Thin Film Transistor ◽  
Metal Halide ◽  
Light Sources ◽  
Blue Led ◽  
Optical Inspection ◽  
Metal Halide Lamps ◽  
Better Than ◽  
Halogen Lamps

Light sources tend to affect images captured in any automatic optical inspection (AOI) system. In this study, the effectiveness of metal-halide lamps, quartz-halogen lamps, and LEDs as the light sources in AOI systems for the detection of the 3rd and 4th layers electrodes of thin-film-transistor liquid crystal displays (TFT-LCDs) is examined experimentally. The results show that the performance of LEDs is generally comparable or better than that of metal-halide and quartz-halogen lamps. The best optical performance is by the blue LED due to its spectrum compatibility with the time-delay-integration charged-coupled device (TDI CCD) sensor and its better spatial resolution. The images revealed by the blue LED are sharper and more distinctive. Since current LEDs are more energy efficient and environmentally friendly, using LEDs as the light source for AOI is very beneficial. As the blue LED performs the best, it should be adopted for AOI using TDI CCD sensors.

The Potential of Photoelectrochemical Carbon Sinks

2018 ◽  
Author(s):  
Matthias May ◽  
Kira Rehfeld
Keyword(s):  
Global Warming ◽  
High Temperature ◽  
Greenhouse Gas ◽  
Large Scale ◽  
High Efficiency ◽  
Carbon Sink ◽  
Solar Fuels ◽  
Negative Emissions ◽  
Viable Approach ◽  
Low Sensitivity

Greenhouse gas emissions must be cut to limit global warming to 1.5-2C above preindustrial levels. Yet the rate of decarbonisation is currently too low to achieve this. Policy-relevant scenarios therefore rely on the permanent removal of CO<sub>2</sub> from the atmosphere. However, none of the envisaged technologies has demonstrated scalability to the decarbonization targets for the year 2050. In this analysis, we show that artificial photosynthesis for CO<sub>2</sub> reduction may deliver an efficient large-scale carbon sink. This technology is mainly developed towards solar fuels and its potential for negative emissions has been largely overlooked. With high efficiency and low sensitivity to high temperature and illumination conditions, it could, if developed towards a mature technology, present a viable approach to fill the gap in the negative emissions budget.<br>

The Potential of Photoelectrochemical Carbon Sinks

2018 ◽  
Author(s):  
Matthias May ◽  
Kira Rehfeld
Keyword(s):  
Global Warming ◽  
High Temperature ◽  
Greenhouse Gas ◽  
Large Scale ◽  
High Efficiency ◽  
Carbon Sink ◽  
Solar Fuels ◽  
Negative Emissions ◽  
Viable Approach ◽  
Low Sensitivity

Greenhouse gas emissions must be cut to limit global warming to 1.5-2C above preindustrial levels. Yet the rate of decarbonisation is currently too low to achieve this. Policy-relevant scenarios therefore rely on the permanent removal of CO<sub>2</sub> from the atmosphere. However, none of the envisaged technologies has demonstrated scalability to the decarbonization targets for the year 2050. In this analysis, we show that artificial photosynthesis for CO<sub>2</sub> reduction may deliver an efficient large-scale carbon sink. This technology is mainly developed towards solar fuels and its potential for negative emissions has been largely overlooked. With high efficiency and low sensitivity to high temperature and illumination conditions, it could, if developed towards a mature technology, present a viable approach to fill the gap in the negative emissions budget.<br>

Peculiarities of the phytosanitary state of pome fruits in industrial horticulture

2020 ◽  
Vol 60 (1) ◽  
pp. 159-168
Author(s):  
V. V. Antonenko ◽  
A. V. Zubkov ◽  
S. N. Kruchina
Keyword(s):  
Mechanism Of Action ◽  
Large Scale ◽  
High Efficiency ◽  
Fruit Trees ◽  
Fruit Crops ◽  
Planting Material ◽  
Relative Safety ◽  
Pome Fruits ◽  
Weed Plants ◽  
Spread Of Infection

Data were obtained on the basis of the results of research carried out on the territory of the educational and experimental farm of the Timiryazev State Agrarian University, in Moscow during 2018-2019. As a result of the surveys, the most dangerous diseases and pests of pome crops on the territory of this farm were established. The most resistant apple and pear varieties to major diseases have been identified. Peculiarities of development of alternariosis on pear are described, the harmfulness of the disease on pear and apple seedlings is noted. A possible role in the transfer of alternariosis infection from garden-protective plantations and weed vegetation to fruit trees was noted. A possible role has been established in the transport of septoriosis, powdery dew infection from dicotyledonous weeds plants. The peculiarities of the spread of infection under the influence of wind direction are noted. The results and peculiarities of the application of various methods of scaring birds in the orchard are presented. As a result of route surveys the most harmful weed plants have been identified. The possibility of using herbicides of different mechanism of action in fruit gardens for weed control has been studied. High efficiency and relative safety of application of herbicides of contact action in nursery fields, operational orchards and for control of piglets on fruit trees are shown. Recommendations are given for the use of soil and systemic herbicides of soil in seedlings beds, the first and second fields of the nursery, as well as in the process of production of large-scale planting material and operational orchards of fruit crops. The safety of the herbicides in question is established when used in accordance with the recommended methods of use.

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