检索结果-南通市图书馆

Combustion synthesis of Ce^(3+), Eu^(3+) and Dy^(3+) activated NaCaPO_4 phosphors

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2011年第6期29卷 527-535页

作者： K N Shinde S J Dhoble Animesh Kumar Department of Physics RTM Nagpur University National Environmental Engineering Research Institute

The preparation of NaCaPO4 doped with rare earth （RE） ions Ce3＋, Eu3＋ and Dy3＋ by combustion method was described. Under UV excitation （251 nm） of NaCaPO4：Ce3＋ showsd emission （367 nm） in UV range. When NaCaPO4：Dy3＋ phosphor was excited at 349 nm, the emission spectrum showed intense bands at 482 nm （blue） and 576 nm （yellow）. In Eu activated NaCaPO4 phosphor, the emission spectrum showed a dominant peak at 594 nm （orange） while others were at 614 and 621 nm （red） when excited at 393 nm. The prepared phosphor was characterized by X-ray diffraction （XRD）, scanning electron microscope （SEM） and photoluminescence （PL） measurement. Thus, the photoluminescence behavior of NaCaPO4：Ce3＋ was strongly suggested for scintillator. Likewise, Eu3＋ and Dy3＋ activated NaCaPO4 phosphors were recommended for near-UV white light-emitting diodes （LEDs）.

关键词： combustion synthesis photoluminescence phosphor scintillator solid state lighting rare earths

Preparation and properties of GAGG:Ce/glass composite scintillation material

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2021年第7期30卷 274-282页

作者： Wei-Jie Zhang Qin-Hua Wei Xiao Shen Gao Tang Zhen-Hua Chen Lai-Shun Qin Hong-Sheng Shi College of Materials and Chemistry China Jiliang UniversityHangzhou 310018China Xinjiang Technical Institute of Physics&Chemistry Chinese Academy of SciencesUrumqi 830011China

The translucent GGAG:Ce/glass composites are prepared successfully by ball-milling,tableting,and pressureless *** thickness of composites is about 400μ*** x-ray diffraction(XRD),differential scanning calorimetry(DSC),density of composite materials are measured and discussed *** scanning electron microscopy(SEM)and energy dispersive spectrometer(EDS)elemental mapping are employed to analyze the particle size,the shape of powders,and the distribution of GGAG:Ce particles in the glass matrix,*** decay time,ultraviolet,(UV),x-ray excitation luminescence spectra,and temperature spectra are *** results show that the composite materials have high light output,good thermostability,and short decay *** method adopted in this work is an effective method to reduce the preparation time and cost of the *** ultralow afterglow indicates that the composite materials have an opportunity to be used for x-ray detection and imaging.

关键词： GGAG:Ce composite material scintillator glass matrix luminescence properties

A new method for position-sensitive measurement of beta surface contamination

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2017年第2期28卷 49-56页

作者： Yan-Tao Qu Hui Wang Yang Liu Ling Chen Jie Hou Zhe Liu Ji-Zeng Ma Department of Radiation Protection China Institute of Atomic Energy Beijing 102413 China Nuclear and Radiation Safety Center Ministry of Environment Protection Beijing 100082 China Occupational Radiation Protection Unit Radiation Safety and Monitoring Section NSRW IAEA PO Box 1001400 Vienna Austria

In this paper, we propose a new method for position-sensitive measurement of beta surface contamination. With a position-sensitive detector of enlarged sensitive detection area, accurate information of the contamination distribution can be obtained. The positionsensitive detection is based on a large-area plastic scintillator and the wavelength shifting(WLS) fibers and adopts the ‘‘light center of gravity'' method. Optical transmission of the detector is simulated with a preliminary detector model, and feasibility of the detector design and measurement method is evaluated using an experiment *** simulation and experiment results at different beta-ray incident points on the scintillator surface show that there is a polynomial relationship between the average amplitude ratio of the output pulses from the two parallel WLS fibers in the same fiber layer and the relative distance from the incident point to the WLS fiber.

关键词： Beta surface contamination Position-sensitive measurement Wavelength shifting fibers Plastic scintillator

Neutron and Ion Beams Emitted from Plasma Focus (112.5 J) Device

在线全文

学校读者我要写书评

暂无评论

Plasma Science and Technology 2010年第1期12卷 1-5页

作者： G.M.EL-ARAGI Plasma Physics and Nuclear Fusion Department Nuclear Research Center

Preliminary results of recent experiments performed within the Mather-type 112.5 J plasma focus device are presented. The ion beams from the focus device operated with deuterium filling at 1 mbar were registered using CR-39 solid state nuclear track detectors （SSNTD） and a Faraday cup detector for time-resolved measurements. The time-resolved neutron emission from the focus region measurements was detected with a photomultiplier tube （IP-28） optically coupled with a plastic scintillator NE 102.

关键词： plasmas neutron scintillator detectors photomultiplier Faraday

Improvement of Luminescent Properties of PbWO_4 by Doping with Gd^(3+) Ions

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2002年第1期20卷 19-22页

作者：周东方陈永虎施朝淑刘波 NationalSynchrotronRadiationLaboratory UniversityofScienceandTechnologyofChinaHefei230029China DepartmentofPhysics UniversityofScienceandTechnologyofChinaHefei230026China

The luminescent properties of PbWO 4∶Gd 3+ were studied. The luminescence of Gd 3+ in PbWO 4∶Gd 3+ was quenched. It is possible that the excitation states of Gd 3+ locate in the conduction band of PbWO 4 crystal. The luminescent intensity of the green and the blue band of PbWO 4 emission increases by doping with about 0 005% and 0 01% (molar fraction) Gd 3+ respectively. Mechanism of this enhancement of PbWO 4∶Gd 3+ luminescence is probably due to energy transfer from Gd 3+ to PbWO 4 host in the crystal. The PbWO 4 doped with low concentration of Gd (about 0 005%～0 01%) is a good scintillating material.

关键词： rare earths PbWO 4 crystal luminescence scintillator Gd 3+ ion

Optical and scintillation properties of Ce:Y_(3)Al_(5)O_(12) single crystal fibers grown by laser heated pedestal growth method

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2021年第12期39卷 1533-1539,I0003页

作者： Xibin Wang Yun Dai Zhonghan Zhang Liangbi Su Huamin Kou Yangxiao Wang Anhua Wu State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201899China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049.China

The single crystal scintillating optical fibers acting as the scintillators and light conductors show potential application in scintillating fiber array detectors with high spatial *** this paper we report the growth of 0.2 at%Ce:Y_(3)Al_(5)O_(12) single crystal *** crystalline phase,surface morphology of the axialsection and cro ss-section,optical and scintillation properties of the as-grown fiber were *** Ce:Y_(3)Al_(5)O_(12) single crystal fiber has a pure YAG phase,a uniform distribution of cerium in the axialsection and cross-section *** spectrum is composed of broad bands ranging from 440 to700 *** addition,the single crystal fiber has a high light yield of 26115±2000 photons/MeV,low energy resolution of 9.44%@662 keV and decay time of a fast component of 78 ns and a slow component of 301 *** intensity ratio of fast to slow components is roughly 8:1.

关键词： Ce:Y_(3)Al_(5)O_(12) Single crystal fiber Laser heated pedestal growth method Rare earth scintillator

Photoluminescence and radioluminescence properties of (Gd8Ca2)(SiO4)6O2 crystals with different concentrations of Ce

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2017年第11期35卷 1071-1076页

作者： Takuya Igashira Masaki Mori Go Okada Noriaki Kawaguchi Takayuki Yanagida Graduate School of Materials Science Nara Institute of Sdence and Technology (NAIST) 8916-5 Takayama Ikoma Nam Japan

(GdCa)(SiO)Oapatite crystals doped with different concentrations of Ce were synthesized by the Floating Zone(FZ) method, and we have evaluated the photoluminescence(PL) and radio luminescence(RL) properties. In PL, an emission band appeared around 400 nm under excitation at 300 nm due to the5 d-4 f transitions of Ce3+. The PL decay curves were approximated by a second-order exponential decay function, and the derived decay time constants ranged around 20-25 ns and 40-480 ns. Similar emission was observed in RL, but the decay time constants were much longer than those in PL. The RL afterglow was the lowest in the 1.0% Ce-doped sample. The 1.0% and 2.0% Ce-doped samples showed a full-energy peak in the pulse height spectrum measured underAm 5.5 MeV α-ray irradiation, and the absolute scintillation light yields were estimated to be around 55 and 36 ph/5.5 MeV-a, respectively.

关键词： scintillator Apatite Ce^(3+) 5d-4f transition

Growth of LaBr_3:Ce^(3+) Single Crystal by Vertical Bridgman Process in Nonvacuum Atmosphere

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2009年第6期25卷 753-757页

作者： Hongbing Chen Changyong Zhou Peizhi Yang Jinhao Wang State Key Laboratory Base of-Novel Functional Materials & Preparation Science Institute of Materials Science & Engineering Ningbo University Ningbo 315211 China Key Laboratory of Advanced Technique & Preparation for Renewable Energy Materials Ministry of Education Yunnan Normal University Kunming 650092 China

The growth of LaBrs：Ce^3＋ crystal by the vertical Bridgman process in a nonvacuum atmosphere was reported. According to the dehydration procedure of LaBr3·7H2O and CeBr3·7H2O investigated by differential thermal analysis/thermogravimetry （DTA/TG）, anhydrous LaBr3 and CeBr3 were prepared by heating LaBr3·7H2O and CeBr3·7H2O at 240-260℃ for 5-6 h in dried HBr atmosphere. Using the feed materials prepared from the anhydrous lanthanon bromides, a 0.5 mole fraction Ce^3＋ doped LaBr3 crystal with size ofФ25 mm×50 mm had been grown by vertical Bridgman process successfully. By sealing the feed material in a platinum crucible, the crystal could be grown in a nonvacuum atmosphere as the oxidization and volatilization of the melt could be avoided. The crystal was grown with the optimum conditions such as a growth rate of 0.5-1.0 mm/h and a temperature gradient of around 30℃/cm across solid-liquid interface under a furnace temperature of 850-880℃. The crystal was characterized by DTA/TG, X-ray diffraction （XRD）, optical transmission, photoluminescence and X-ray stimulated luminescence measurement. The Bridgman process was confirmed to be promising for growing transparent LaBr3：Ce^3＋ crystal with high optical quality.

关键词： LaBr3:Ce^3+ scintillator Dehydration Crystal growth Bridgman process

同方期刊数据库

Unfolding analysis of LaBr3:Ce gamma spectrum with a detector response matrix constructing algorithm based on energy resolution calibration

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2018年第1期29卷 23-31页

作者： Rui Shi Xian-Guo Tuo Huai-Liang Li Yang-Yang Xu Fan-Rong Shi Jian-Bo Yang Yong Luo Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory Southwest University of Science and Technology Mianyang 621010 China Sichuan University of Science and Engineering Zigong 643000 China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China

With respect to the gamma spectrum, the energy resolution improves with increase in energy. The counts of full energy peak change with energy, and this approximately complies with the Gaussian distribution. This study mainly examines a method to deconvolve the LaBr_3:Ce gamma spectrum with a detector response matrix constructing algorithm based on energy resolution *** the algorithm, the full width at half maximum(FWHM)of full energy peak was calculated by the cubic spline interpolation algorithm and calibrated by a square root of a quadratic function that changes with the energy. Additionally, the detector response matrix was constructed to deconvolve the gamma spectrum. Furthermore, an improved SNIP algorithm was proposed to eliminate the background. In the experiment, several independent peaks of ^(152)Eu,^(137)Cs, and ^(60)Co sources were detected by a LaBr_3:Ce scintillator that were selected to calibrate the energy resolution. The Boosted Gold algorithm was applied to deconvolve the gamma spectrum. The results showed that the peak position difference between the experiment and the deconvolution was within ± 2 channels and the relative error of peak area was approximately within 0.96–6.74%. Finally, a ^(133) Ba spectrum was deconvolved to verify the efficiency and accuracy of the algorithm in unfolding the overlapped peaks.

关键词： Detector response matrix Energy resolution calibration LaBr3:Ce scintillator SNIP background elimination Boosted Gold deconvolution algorithm