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Combing Type-Aware Attention and Graph Convolutional Networks for Event Detection 被引量:1
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作者 kun ding Lu Xu +5 位作者 Ming Liu Xiaoxiong Zhang Liu Liu Daojian Zeng Yuting Liu Chen Jin 《Computers, Materials & Continua》 SCIE EI 2023年第1期641-654,共14页
Event detection(ED)is aimed at detecting event occurrences and categorizing them.This task has been previously solved via recognition and classification of event triggers(ETs),which are defined as the phrase or word m... Event detection(ED)is aimed at detecting event occurrences and categorizing them.This task has been previously solved via recognition and classification of event triggers(ETs),which are defined as the phrase or word most clearly expressing event occurrence.Thus,current approaches require both annotated triggers as well as event types in training data.Nevertheless,triggers are non-essential in ED,and it is time-wasting for annotators to identify the“most clearly”word from a sentence,particularly in longer sentences.To decrease manual effort,we evaluate event detectionwithout triggers.We propose a novel framework that combines Type-aware Attention and Graph Convolutional Networks(TA-GCN)for event detection.Specifically,the task is identified as a multi-label classification problem.We first encode the input sentence using a novel type-aware neural network with attention mechanisms.Then,a Graph Convolutional Networks(GCN)-based multilabel classification model is exploited for event detection.Experimental results demonstrate the effectiveness. 展开更多
关键词 Event detection information extraction type-aware attention graph convolutional networks
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A Knowledge-Enriched and Span-Based Network for Joint Entity and Relation Extraction 被引量:4
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作者 kun ding Shanshan Liu +4 位作者 Yuhao Zhang Hui Zhang Xiaoxiong Zhang Tongtong Wu Xiaolei Zhou 《Computers, Materials & Continua》 SCIE EI 2021年第7期377-389,共13页
The joint extraction of entities and their relations from certain texts plays a significant role in most natural language processes.For entity and relation extraction in a specific domain,we propose a hybrid neural fr... The joint extraction of entities and their relations from certain texts plays a significant role in most natural language processes.For entity and relation extraction in a specific domain,we propose a hybrid neural framework consisting of two parts:a span-based model and a graph-based model.The span-based model can tackle overlapping problems compared with BILOU methods,whereas the graph-based model treats relation prediction as graph classification.Our main contribution is to incorporate external lexical and syntactic knowledge of a specific domain,such as domain dictionaries and dependency structures from texts,into end-to-end neural models.We conducted extensive experiments on a Chinese military entity and relation extraction corpus.The results show that the proposed framework outperforms the baselines with better performance in terms of entity and relation prediction.The proposed method provides insight into problems with the joint extraction of entities and their relations. 展开更多
关键词 Entity recognition relation extraction dependency parsing 1 Introduction
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Electrically driven uniaxial stress device for tuning in situ semiconductor quantum dot symmetry and exciton emission in cryostat
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作者 Hao Chen Xiuming Dou +1 位作者 kun ding Baoquan Sun 《Journal of Semiconductors》 EI CAS CSCD 2019年第7期75-79,共5页
Uniaxial stress is a powerful tool for tuning exciton emitting wavelength, polarization, fine-structure splitting (FSS), and the symmetry of quantum dots (QDs). Here, we present a technique for applying uniaxial stres... Uniaxial stress is a powerful tool for tuning exciton emitting wavelength, polarization, fine-structure splitting (FSS), and the symmetry of quantum dots (QDs). Here, we present a technique for applying uniaxial stress, which enables us in situ to tune exciton optical properties at low temperature down to 15 K with high tuning precision. The design and operation of the device are described in detail. This technique provides a simple and convenient approach to tune QD structural symmetry, exciton energy and biexciton binding energy. It can be utilized for generating entangled and indistinguishable photons. Moreover, this device can be employed for tuning optical properties of thin film materials at low temperature. 展开更多
关键词 UNIAXIAL stress electrically DRIVEN DEVICE low temperature quantum DOTS thin film materials
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Pressure-and temperature-dependent luminescence from Tm^(3+) ions doped in GdYTaO_(4)
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作者 Peng-Yu Zhou Xiu-Ming Dou +6 位作者 Bao-Quan Sun Ren-Qin Dou Qing-Li Zhang Bao Liu Pu-Geng Hou Kai-Lin Chi kun ding 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期497-503,共7页
Luminescent properties of Tm^(3+)-doped GdYTaO_(4) are studied for exploring their potential applications in temperature and pressure sensing.Two main emission peaks from ^(3)H_(4)→^(3)H_(6) transition of Tm^(3+)are ... Luminescent properties of Tm^(3+)-doped GdYTaO_(4) are studied for exploring their potential applications in temperature and pressure sensing.Two main emission peaks from ^(3)H_(4)→^(3)H_(6) transition of Tm^(3+)are investigated.Intensity ratio between the two peaks evolves exponentially with temperature and has a highest sensitivity of 0.014 K^(−1) at 32 K.The energy difference between the two peaks increases linearly with pressure increasing at a rate of 0.38 meV/GPa.Intensity ratio between the two peaks and their emission lifetimes are also analyzed for discussing the pressure-induced variation of the sample structure.Moreover,Raman spectra recorded under high pressures indicate an isostructural phase transition of GdYTaO_(4) occurring at 4.46 GPa. 展开更多
关键词 rare-earth tantalate photoluminescence high pressure RAMAN
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Exciton emission dynamics in single InAs/GaAs quantum dots due to the existence of plasmon-field-induced metastable states in the wetting layer
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作者 Junhui Huang Hao Chen +8 位作者 Zhiyao Zhuo Jian Wang Shulun Li kun ding Haiqiao Ni Zhichuan Niu Desheng Jiang Xiuming Dou Baoquan Sun 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第9期552-557,共6页
A very long lifetime exciton emission with non-single exponential decay characteristics has been reported for single InA-s/GaAs quantum dot(QD)samples,in which there exists a long-lived metastable state in the wetting... A very long lifetime exciton emission with non-single exponential decay characteristics has been reported for single InA-s/GaAs quantum dot(QD)samples,in which there exists a long-lived metastable state in the wetting layer(WL)through radiative field coupling between the exciton emissions in the WL and the dipole field of metal islands.In this article we have proposed a new three-level model to simulate the exciton emission decay curve.In this model,assuming that the excitons in a metastable state will diffuse and be trapped by QDs,and then emit fluorescence in QDs,a stretchedlike exponential decay formula is derived as I(t)=At^(β−1)e^(−(rt)^(β)),which can describe well the long lifetime decay curve with an analytical expression of average lifetime(τ)=1/rГ(1/β+1),where G is the Gamma function.Furthermore,based on the proposed three-level model,an expression of the second-order auto-correlation function g^(2)(t)which can fit the measured g^(2)(t)curve well,is also obtained. 展开更多
关键词 quantum dots collective excitations charge carriers time resolved spectroscopy
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Influence of Polar Pressure Transmission Medium on the Pressure Coefficient of Excitonic Interband Transitions in Monolayer WSe_2
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作者 Shun-yu Zhou Yan-xia Ye +3 位作者 kun ding De-sheng Jiang Xiu-ming Dou Bao-quan Sun 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第6期45-49,共5页
The influence of the pressure transmission medium(PTM)on the excitonic interband transitions in monolayer tungsten diselenide(WSe2)is investigated using photoluminescence(PL)spectra under hydrostatic pressure up... The influence of the pressure transmission medium(PTM)on the excitonic interband transitions in monolayer tungsten diselenide(WSe2)is investigated using photoluminescence(PL)spectra under hydrostatic pressure up to 5GPa.Three kinds of PTMs,condensed argon(Ar),1:1 n-pentane and isopentane mixture(PM),and4:1 methanol and ethanol mixture(MEM,a PTM with polarity),are used.It is found that when either Ar or PM is used as the PTM,the PL peak of exciton related to the direct K-K interband transition shows a pressure-induced blue-shift at a rate of 32±4 or 32±1 meV/GPa,while it turns to be 50±9meV/GPa when MEM is used as the PTM.The indirect A-K interband transition presents almost no shift with increasing pressure up to approximatel.y 5 GPa when Ar and PM are used as the PTM,while it shows a red-shift at the rate of-17±7meV/GPa by using MEM as the PTM.These results reveal that the optical interband transitions of monolayer WSe2 are very sensitive to the polarity of the PTM.The anomalous pressure coefficient obtained using the polar PTM of MEM is ascribed to the existence of hydrogen-like bonds between hydroxyl in MEM and Se atoms under hydrostatic pressure. 展开更多
关键词 PTM MEM Influence of Polar Pressure Transmission Medium on the Pressure Coefficient of Excitonic Interband Transitions in Monolayer WSe2
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Optical Properties of Atomic Defects in Hexagonal Boron Nitride Flakes under High Pressure
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作者 Xiao-Yu Zhao Jun-Hui Huang +5 位作者 Zhi-Yao Zhuo Yong-Zhou Xue kun ding Xiu-Ming Dou Jian Li Bao-Quan Sun 《Chinese Physics Letters》 SCIE CAS CSCD 2020年第4期53-56,共4页
We investigate the pressure spectral characteristics and the effective tuning of defect emissions in hexagonal boron nitride(hBN) at low temperatures using a diamond anvil cell(DAC). It is found that the redshift rate... We investigate the pressure spectral characteristics and the effective tuning of defect emissions in hexagonal boron nitride(hBN) at low temperatures using a diamond anvil cell(DAC). It is found that the redshift rate of emission energy is up to 10 meV/GPa, demonstrating a controllable tuning of single photon emitters through pressure.Based on the distribution character of pressure coefficients as a function of wavelength, different kinds of atomic defect states should be responsible for the observed defect emissions. 展开更多
关键词 DEFECT HEXAGONAL BORON
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Multi-Objective Optimal Dispatch Considering Wind Power and Interactive Load for Power System
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作者 Xinxin Shi Guangqing Bao +1 位作者 kun ding Liang Lu 《Energy and Power Engineering》 2018年第4期1-10,共10页
With the rapid and large-scale development of renewable energy, the lack of new energy power transportation or consumption, and the shortage of grid peak-shifting ability have become increasingly serious. Aiming to th... With the rapid and large-scale development of renewable energy, the lack of new energy power transportation or consumption, and the shortage of grid peak-shifting ability have become increasingly serious. Aiming to the severe wind power curtailment issue, the characteristics of interactive load are studied upon the traditional day-ahead dispatch model to mitigate the influence of wind power fluctuation. A multi-objective optimal dispatch model with the minimum operating cost and power losses is built. Optimal power flow distribution is available when both generation and demand side participate in the resource allocation. The quantum particle swarm optimization (QPSO) algorithm is applied to convert multi-objective optimization problem into single objective optimization problem. The simulation results of IEEE 30-bus system verify that the proposed method can effectively reduce the operating cost and grid loss simultaneously enhancing the consumption of wind power. 展开更多
关键词 WIND Power Interactive Load Optimal DISPATCH MULTI-OBJECTIVE QPSO Models
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Photocatalytic Property of White Cement Pastes Surface-treated BiOBr@SiO2 core-shell Structures
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作者 Dan Wang Xin Cheng kun ding 《功能材料信息》 2016年第3期53-53,共1页
关键词 英语 阅读 理解 生态环境材料
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Correlation between Phase Composition,Microstructure,and Electrochemical Behavior of Cobalt Compounds
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作者 kun ding Dan Wang Xin Cheng 《功能材料信息》 2016年第2期43-43,共1页
Cobalt compounds with different phase compositions and microstructure are promising in solving the energy storage and conversion problems.Herein,the graphene-likeα-Co(OH)_2,ultra-layeredα-Co(OH)_2 stacked with hexag... Cobalt compounds with different phase compositions and microstructure are promising in solving the energy storage and conversion problems.Herein,the graphene-likeα-Co(OH)_2,ultra-layeredα-Co(OH)_2 stacked with hexagonal nanosheets,and needle-like Co(CO_3)0.5(OH)·0.11H_2O were hydrothermally synthesized without using surfactant and templates by increasing the reaction temperature or prolonging the 展开更多
关键词 英语 阅读 理解 纳米材料与技术
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Spin selectivity of chiral mesostructured diamagnetic BiOBr films 被引量:2
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作者 kun ding Jing Ai +5 位作者 Hao Chen Zhibei Qu Peizhao Liu Lu Han Shunai Che Yingying Duan 《Nano Research》 SCIE EI CSCD 2023年第8期11444-11449,共6页
The chirality-induced spin selectivity(CISS)has been found in the antiferromagnetic and paramagnetic chiral inorganic materials with unpaired electrons,while rarely reported in the spin-paired diamagnetic inorganic ma... The chirality-induced spin selectivity(CISS)has been found in the antiferromagnetic and paramagnetic chiral inorganic materials with unpaired electrons,while rarely reported in the spin-paired diamagnetic inorganic materials with spin-pairing energy.Here,we report the CISS in the spin-paired diamagnetic BiOBr endowed with three levels of chiral mesostructures.Chiral mesostructured BiOBr films(CMBFs)were fabricated through a sugar alcohol-induced hydrothermal route.The antipodal CMBFs exhibited chirality-dependent,magnetic field-independent magnetic circular dichroism(MCD)signals,which indicates the existence of spin selectivity.The spin selectivity of CMBFs was speculated to be the result of the competing effect between the externally applied magnetic field and the effective magnetic field arisen from the spin electron motions in chiral potential.The chirality-induced effective magnetic field acts on the magnetic moment of electrons,potentially overcoming the spin-pairing energy and producing opposite energy changes for spin-down and spin-up electrons. 展开更多
关键词 chiral mesostructures diamagnetic material chiral-induced spin selectivity(CISS) magnetic circular dichroism(MCD)
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有生育要求子宫腺肌病患者的妊娠结局真实世界临床数据分析 被引量:8
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作者 桑昌美 石丘玲 +4 位作者 康彦君 崔丽梅 丁琨 刘小强 赵淑萍 《中华妇产科杂志》 CAS CSCD 北大核心 2022年第4期265-270,共6页
目的回顾性分析有生育要求子宫腺肌病患者的妊娠结局。方法选取2015年6月至2020年5月在青岛大学附属妇女儿童医院就诊的有生育要求、超声诊断为妊娠合并子宫腺肌病且临床资料完整的患者231例。根据妊娠前子宫腺肌病的治疗方式分为:期待... 目的回顾性分析有生育要求子宫腺肌病患者的妊娠结局。方法选取2015年6月至2020年5月在青岛大学附属妇女儿童医院就诊的有生育要求、超声诊断为妊娠合并子宫腺肌病且临床资料完整的患者231例。根据妊娠前子宫腺肌病的治疗方式分为:期待组78例、药物组111例和手术组42例, 分析3组患者治疗前的一般资料, 并总结妊娠结局。再根据早孕期是否予药物保胎治疗, 将自然受孕的无先兆流产症状的患者分为观察组和保胎组, 比较两组患者的早孕期妊娠结局。结果 (1)与期待组相比, 药物组和手术组患者的年龄较大, 分别为(31.5±1.8)、(34.1±3.7)、(36.9±3.6)岁(P<0.05)。期待组有临床症状的患者比例低, 仅占11.5%(9/78), 而药物组和手术组患者发生痛经、经量增多的比例较高。药物组和手术组患者的子宫体积大于期待组, 分别为(151±46)、(166±27)、(97±18)cm^(3)(P<0.05)。手术组患者78.6%(33/42)为局灶型病灶。期待组患者自然受孕的比例为97.4%(76/78), 药物组和手术组患者以辅助生殖治疗为主。(2)期待组、药物组、手术组患者的流产率分别为48.7%(38/78)、46.8%(52/111)、59.5%(25/42)。与药物组和手术组相比, 期待组患者的早产率低, 分别为55.9%(33/111)、11/17、12.5%(5/78), 自然分娩率高, 分别为44.1%(26/111)、4/17、67.5%(27/78)。(3)自然受孕无先兆流产症状的患者共89例, 其中观察组31例、保胎组58例;与观察组相比, 保胎组患者流产率低[41.9%(13/31)、34.5%(20/58)], 两组比较, 差异有统计学意义(P<0.05)。结论有生育要求的子宫腺肌病患者应综合评估, 予以个体化治疗方案。妊娠合并子宫腺肌病患者流产率高, 应纳入高危孕产妇管理。早孕期积极进行保胎治疗, 在一定程度上可改善妊娠结局。 展开更多
关键词 子宫腺肌病 妊娠结局 妊娠并发症 临床方案
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Hydrogen-Bonded Engineering Enhancing Phase Transition Temperature in Molecular Perovskite Ferroelastic 被引量:4
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作者 Tie Zhang kun ding +4 位作者 Jun-Yi Li Guo-Wei Du Lu-Lu Chu Yi Zhang Da-Wei Fu 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2022年第13期1559-1565,I0002,共8页
The broad operating temperature range is sought for molecular ferroic materials who are expected to be applied to flexible and electronic materials.Hydrogen bonds,an effective force between molecules,are important to ... The broad operating temperature range is sought for molecular ferroic materials who are expected to be applied to flexible and electronic materials.Hydrogen bonds,an effective force between molecules,are important to regulate the molecule structure and their condition,helping a higher temperature range for ferroic materials.Here,we report a molecular perovskite ferroelastic(Me-Hdabco)Rb[BF_(4)]_(3)(Me-Hdabco=N-methyldabconium)which shows high temperature(T_(1)=322.5 K and T_(2)=381K)ferroelastic phase transitions.The ferroelastic phase transition temperature range of(Me-Hdabco)Rb[BF_(4)]_(3) is significantly increased by 71 K compared with[Meda-bco-F]Rb[BF_(4)]_(3)(Medabco-F=1-fluoro-4-methyl-1,4-diazoniabicyclo[2.2.2]octane).Structural analysis and thermal analysis demonstrate the ferroelastic phase transition is mainly attributed to dynamic cations order and disorder transformation.Therefore,new hydrogen bonds generated between cations and the Rb_(8)[BF_(4)]_(12) frame increase their intermolecular force,which is beneficial to improving the phase transition temperature.This finding has an important impact on the utilization of weak interactionforces to design and optimize functional materials. 展开更多
关键词 Molecular dynamics Ferroelastic crystal Dielectric Hydrogen bonds Phase transitions
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Optical properties of Nd^(3+) ions doped GdTaO_(4) for pressure and temperature sensing 被引量:2
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作者 Pengyu Zhou Qingli Zhang +6 位作者 Fang Peng Baoquan Sun Xiuming Dou Bao Liu Dandan Han Yongzhou Xue kun ding 《Journal of Rare Earths》 SCIE EI CAS CSCD 2022年第6期870-877,I0001,共9页
Pressure-and temperature-dependent luminescence properties of ^(3)F_(3/2)→^(4)I9/2 transition of Nd^(3+):GdTaO_(4) were studied for potential applications in optical sensing.Two isolated emission lines corresponding ... Pressure-and temperature-dependent luminescence properties of ^(3)F_(3/2)→^(4)I9/2 transition of Nd^(3+):GdTaO_(4) were studied for potential applications in optical sensing.Two isolated emission lines corresponding to^(3)F_(3/2)(R2,1)→^(4)I_(9/2)(Z5)transitions,located at 920 and 927 nm under ambient condition,are very sensitive to pressure with coefficients of-15.6 and-14.5 cm^(-1)/GPa determined in a pressure range up to about 9 GPa.The luminescence intensity ratio between the two emission lines exhibits a large dependence with temperature in a range from 80 to 620 K,the corresponding temperature sensitivity at room temperature is similar to that of Nd^(3+):YAG.These advantages,together with the other observed features of high stable position relationship under pressure and low thermal shifts for the two emission lines indicate that Nd^(3+):GdTaO_(4) is a promising candidate to be used as pressure and temperature sensors in the near-infrared spectral range. 展开更多
关键词 Trivalent neodymium ion Rare-earth tantalate Near-infrared luminescence Pressure sensing Temperature sensing
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Community dynamics of ammonia oxidizing bacteria in a fullscale wastewater treatment system with nitrification stability 被引量:2
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作者 Xiaohui WANG Xianghua WEN +2 位作者 Hengjing YAN kun ding Man HU 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2011年第1期92-98,共7页
To determine whether the functional stability of nitrification was correlated to a stable community structure of ammonia oxidizing bacteria(AOB)in a fullscale wastewater treatment plant,the AOB community dynamics in a... To determine whether the functional stability of nitrification was correlated to a stable community structure of ammonia oxidizing bacteria(AOB)in a fullscale wastewater treatment plant,the AOB community dynamics in a wastewater treatment system was monitored over one year.The community dynamics were investigated using specific PCR followed by terminal restriction fragment length polymorphism(T-RFLP)analysis of the amoA gene.The T-RFLP results indicated that during the period of nitrification stability,the AOB community structure in the full-scale wastewater treatment system was relatively stable,and the average change rate every 15 d of the system was 6.6%±5.8%.The phylogenetic analysis of the cloned amoA gene showed clearly that the dominant AOB in the system was Nitrosomonas spp.The results of this study indicated that throughout the study period,the AOB community structure was relatively stable in the full-scale wastewater treatment system with functional stability of nitrification. 展开更多
关键词 ammonia-oxidizing bacteria(AOB) community dynamics terminal restriction fragment length polymorphism(T-RFLP) nitrification performance
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Self-adaptive phosphor coating technology for white LED packaging 被引量:2
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作者 Haibo RAO kun ding +5 位作者 Jirong SONG Likun XIE Wei WANG Xianlong WAN Linsong ZHOU Junyuan LIAO 《Frontiers of Optoelectronics》 2012年第2期147-152,共6页
Phosphor-converted light-emitting diodes (pc- LEDs), which employ blue LEDs with yellow phosphors to generate white light illumination, is a widely used solid- state lighting source. In order to conduct a phosphor l... Phosphor-converted light-emitting diodes (pc- LEDs), which employ blue LEDs with yellow phosphors to generate white light illumination, is a widely used solid- state lighting source. In order to conduct a phosphor layer coating with high quality on LED chip, a self-adaptive coating technology is introduced in this paper. A slurry coating technique combined with selfexposure method is applied and developed to demonstrate the benefits of selfadaptive coating layer. For self-exposure, the slurry coating is exposed to the blue emission of LED itself other than to ultraviolet (UV) light outside to make photoresist crosslinking. Results of measurement indicate that white LEDs with self-adaptive coating have shown self-adaptability to the angular distribution of intensity of blue light and performed higher spatial color uniformity than those with conventional coating and other conformal coating. 展开更多
关键词 white light-emitting diodes (LEDs) phosphorcoating SELF-ADAPTIVE slurry method SELF-EXPOSURE
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