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Novel colored flames via chromaticity of essential colors

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Defence Technology（防务技术） 2019年第2期15卷 210-215页

作者： Ramy Sadek Mohamed Kassem Mohamed Abdo Ahmed Fahd Hesham Tantawy Amir Elsaidy Sherif Elbasuney School of Chemical Engineering Military Technical College

Colored flame compositions have distinctive variety of applications ranging from military signaling,rocket tracking, and illuminating devices. Certain elements and compounds when heated to high temperature are able to emit unique wavelengths in the visible region. This study, reports on the development of novel colored flames that cannot be generated by emitting atomic/molecular species. This was achieved by using chromaticity of basic colored flames. Mixing of high quality primary colored flames including Blue, Yellow, and Red in proper ratio was conducted; any interfering incandescent emission resulted from MgO was eliminated using Al metal fuel. The spectral characteristics in terms of luminous intensity, and color quality were evaluated using digital luxmeter and UV-Vis. spectrometer *** quality mixed colored flames include violet, sweet pink, and marigold were developed. This study shaded the light on the state of the art for the real development of novel colored flame compositions and chromaticity of basic colored flames.

关键词： Pyrotechnics Colored flame Atomic spectroscopy Molecular spectroscopy Luminous intensity Color quality chromaticity

Study on the effects of chromaticity and magnetic field tracking errors at CSNS/RCS

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Chinese Physics C 2014年第11期38卷 68-71页

作者：许守彦王生安宇文李志平 Institute of High Energy Physics (IHEP)

The Rapid Cycling Synchrotron （RCS） is a key component of the China Spallation Neutron Source （CSNS）. For this type of high intensity proton synchrotron, the chromaticity, space charge effects, and magnetic field tracking errors between the quadrupoles and the dipoles can induce beta function distortion and tune shift, and induce resonances. In this paper, the combined effects of chromaticity, magnetic field tracking errors and space charge on beam dynamics at CSNS/RCS are studied systemically. 3-D simulations with different magnetic field tracking errors are performed by using the code ORBIT, and the simulation results are compared with the case without tracking errors.

关键词： space charge chromaticity magnetic field tracking errors CSNS

Optimized optical design of thin-film transistor arrays for high transmittance and excellent chromaticity

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Frontiers of Materials Science 2020年第1期14卷 89-95页

作者： Chengzhi Luo Shiyu Long Guanghui Liu Cooper Min Zhang Fei Ai School of Electronic and Computer Engineering Peking UniversityShenzhen518055China Wuhan China Star Optoelectronics Technology Co.Ltd. Wuhan430078China

Transmittance and chromaticity are essential requirements for optical performance of thin-film transistor(TFT)***,it is still a challenge to get high transmittance and excellent chromaticity at the same *** this paper,optimized optical design by using antireflection film theory and optical phase modulation is demonstrated in low temperature poly-silicon(LTPS)TFT *** realize high transmittance,the refractive index difference of adjacent films is modified by using silicon oxynitride(SiOxNy)with adjustable refractive *** realize excellent chromaticity,the thicknesses of multilayer films are precisely regulated for antireflection of certain wavelength *** results show that the transmittance and chromaticity have been improved by about 6%and 18‰,respectively,at the same time,which is a big step forward for high optical performance of TFT *** device characteristics of the TFT arrays with the optimal design,such as threshold voltage and electron mobility,are comparable to those of conventional TFT *** optimized optical design results in enhanced power-conversion efficiencies and perfects the multilayer film design on the basic theory,which has great practicability to be applied in TFT arrays.

关键词： TFT array transparent dielectric material chromaticity antireflection film optical phase modulation

Study chromaticity of Solar Spectrum

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International Journal of Astronomy and Astrophysics 2014年第3期4卷 510-518页

作者： Nagendra Nath Mondal Department of Physics Batanagar Institute of Engineering Management and Science (BIEMS)(Techno India Group) Batanagar Kolkata 79 West Bengal India

The chromaticity of solar spectrum is studied with the help of a Solar Spectrum Monitor system that can detect individual color in the spectrum. Recent observations done by the detector on the Solar Radiation and the Erath Milieu Experiment suggest that the sun’s visible spectral irradiance changes from May 2009 to September 2012. The data of Earth’s coordinates and environment have been taken since April 2005 after the devastating Tsunami (December, 2004) of India. The bizarre data of?zenith angle,?azimuth angle, and?temperature?of the Earth’s atmosphere show their changes of maxima and minima epoch to epoch. The data of solar spectrum monitor have been taking since 2009 and significant transformations of colored ratios?ΔRB/W?and?ΔRR/W?per hour are observed among the regions of each solstice between 2009 and 2012. The author advocates that the abrupt vagaries of the Earth’s movements may cause devastating tsunamis, earthquake, volcanic eruption, cyclones and tornadoes in addition of anomalous changes of solar spectral irradiation, humidity, temperature and pressure;those effects may spoil ecological balance and extinct some living species from the soil of the earth.

关键词： Astronomy Atmosphere chromaticity Disaster Irradiation Spectroscopy

Study of K^+ doping on structure and properties of γ-Ce_2S_3

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Journal of Rare Earths 2020年第7期38卷 776-783,I0004页

作者： Xin Li Yueming Li Fusheng Song Zhumei Wang Yan Hong Zhike Li School of Materials Science and Engineering Jingdezhen Ceramic InstituteJingdezhen 333403China National Light Industry Key Laboratory of Functional Ceramic Materials Jingdezhen 333403China Energy Storage and Conversion Ceramic Materials Engineering Laboratory of Jiangxi Province Jingdezhen 333403China

In this study,K+-doped γ-Ce2 S3 was successfully prepared via a gas-solid reaction method using CeO2,K2 CO3,and CS2 as raw *** effects of the suitable sulfide system and different molar ratios of K to Ce(nK/Ce=0-0.30) on the phase composition,crystal structure,chromaticity and thermal stability ofγ-Ce2 S3 were systematically *** γ-Ce2 S3 was obtained by calcining the doped samples at840℃ for 150 *** calcination at the same temperature the undoped K+samples exhibit a pure α-*** with a K/Ce molar ratio(nK/Ce) of 0.10-0.25 comprise only the γ-phase;and when nK/Ce exceeds 0.25,a new heterogeneous phase,KCeS2,*** values of nK/Ce in the range of0-0.25,the γ-Ce2 S3 lattice parameters gradually increases with increasing K+ *** nK/Ceexceedes 0.25,the lattice parameters remains *** nK/Ce increased,the synthesized color gradually changes from red to orange—red and finally,to *** redness value a* reaches the maximum(L*=33.86,a*=36.68,b*=38.15) when nK/Ce=0.10,The nK/Ce=0.10 composition continues to exhibit the y-phase after heat treatment at 420℃ for 10 min in *** K+doping fills the internal vacancies of γ-Ce2 S3 and formed a solid solution,which is beneficial for the stability of its lattice,thus improving the thermal stability of γ-Ce2 S3(from 350 to 420℃).

关键词： γ-Ce2S3 Crystal structure chromaticity Thermal stability Potassium ion doping Rare earths

Combustion synthesis and luminescence properties of LaPO4： Eu （5%）

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Journal of Rare Earths 2009年第2期27卷 182-186页

作者： Mounir Ferhi Karima Horchani-Naifer Mokhtar Férid Research Unit of Rare Earth Materials National Research Center in Sciences of Materials B.P. 95 Hammam-Lif 2050 Tunisia

Rare earth doped materials are an important type of phosphors due to their excellent performance such as stability at high temperature and light emission covering the entire visible domain. The combustion synthesis at acid pH of the monoclinic LaPO4： Eu（5%） powders was described. A mixture of La（NO3）3·6H2O, EuCly6H2O and （NH4）2HPO4 was used as anion precursor and glycin as fuel. The synthesis was followed by structure, morphology characterisation and luminescent properties of the obtained compound. The room temperature emission measurements under ultraviolet excitation at 254 nm were made for the emission transition ^5D0→^7FJ of this phosphor. The CIE （Commission Intemationale de L＇Eclairage） chromatic coordinates, dominant wavelength and colour purity were determined and compared to other luminescent materials obtained by other methods.

关键词： rare earth phosphates combustion optical materials luminescence chromaticity

Treatment of Dyeing Wastewater by Using Positive Pulsed Corona Discharge to Water Surface

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Plasma Science and Technology 2007年第1期9卷 71-75页

作者： Young Sun MOK HyunTaeAHN JoengTaiKIM Department of Chemical Engineering Cheju National UniversityJeju 690-756South Korea Department of Architectural Engineering Kyung Hee UniversityYongin-si446-701South Korea

This study investigated the treatment of textile-dyeing wastewater by using an electrical discharge technique （positive pulsed corona discharge）. The high-voltage electrode was placed above the surface Of the wastewater while the ground electrode was submerged in the wastewater. The electrical discharge starting at the tip of the high voltage electrode propagated toward the surface of the wastewater, producing various oxidative radicals and ozone. Oxygen was used as the working gas instead of air to prevent nitrogen oxides from forming. The simulated wastewater was made up with amaranth, which is a kind of azo dye. The results obtained showed that the chromaticity of the wastewater was almost completely removed within an hour. The ultraviolet/visible spectra of the wastewater treated by the electrical discharge revealed that the total hydrocarbon level also decreased significantly.

关键词： positive pulsed corona discharge textile-dyeing wastewater chromaticity

A betatron tune measurement system based on bunch-by-bunch transverse feedback at the Duke storage ring

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Chinese Physics C 2013年第7期37卷 76-82页

作者：徐卫 W. Z. Wu 李京祎何多慧 Y. K. Wu National Synchrotron Radiation Laboratory (NSRL) University of Science and Technology of China FEL Laboratory TUNL and Department of Physics Duke University

To combat electron beam instabilities, a digital bunch-by-bunch transverse feedback （TFB） system has been developed for the Duke storage ring. While it is capable of suppressing transverse beam instabilities for multibunch operation, the TFB system has not been needed for typical operation of the Duke storage ring. To explore the great potential of this system, we have developed beam diagnostic techniques using the TFB, in particular, the TFB based tune measurement techniques. The tune measurement technique allows us to conduct fast chromaticity measurements, compared with the existing chromaticity measurement system using a network analyzer. This new tune measurement system also enables us to measure the bunch tune for multibunch operation of the Duke storage ring. With the TFB based tune measurement system, we have studied the tune stability of the electron beam in the Duke storage ring. This tune system has also been used to calibrate the tune knob for the Duke storage ring.

关键词： transverse feedback tune chromaticity

Photoluminescence properties of Y_(0.75-x)Gd_xAl_(0.10)BO_3:Eu_(0.10)^(3+),0.05R^(3+)(R= Sc,Bi) (0.00 ≤ x ≤ 0.45)

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Chinese Physics B 2010年第6期19卷 248-253页

作者：李杰王育华董其铮刘吉地 Department of Material Science School of Physics Science and TechnologyLanzhou University

Y0.75-xGdxAl0.10BO3：Eu0.10^3＋,0.05R^3＋（R=Sc,Bi）（0.00≤x≤0.45）powder samples are prepared by solid-state reaction and their luminescence properties are investigated. With the replacement of Y^3＋ ions by Sc^3＋（or Bi^3＋）and Gd^3＋ ions in （Y,Al）BO3：Eu,the intensities of emission at 254 and 147 nm are remarkably improved, because Sc^3＋ inos can absorb UV light and transfer the energy to Eu^3＋ ions efficiently. Moreover, Gd^3＋ and Bi^3＋ ions act as an intermediate ＂bridge＂ between the sensitizer and the activator （Eu^3＋） in energy transfer to produce light in the （Y, Gd）BO3：Bi^3＋, Eu^3＋ system more effectively. After doping an appropriate concentration of Gd^3＋ into Y0.50Gd0.25Al0.10BO3：Eu0.01^3＋,Bi0.05^3＋,the emission intensity reaches its maximum, which is nearly 110% compared with the red commercial phosphor （Y,Gd）BO3：Eu and better chromaticity coordinates （0.650, 0.350） are obtained.

关键词： Sc^3+ Bi^3+ Gd^3+ luminescence intensity chromaticity