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一种白光有机电致发光器件的制备 被引量:15
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作者 侯晶莹 高文宝 +2 位作者 赵毅 孙家鑫 刘式墉 《发光学报》 EI CAS CSCD 北大核心 2003年第3期270-274,共5页
通过对器件结构的优化设计,提高了白光电致发光器件中蓝光成分的发光效率,从而得到了一种较为理想的有机白光电致发光器件。驱动电压为5V时,电流密度J=0 5mA/cm2,器件的效率达到最大,流明效率为1 92lm/W,此时器件的发光亮度接近20cd/m2... 通过对器件结构的优化设计,提高了白光电致发光器件中蓝光成分的发光效率,从而得到了一种较为理想的有机白光电致发光器件。驱动电压为5V时,电流密度J=0 5mA/cm2,器件的效率达到最大,流明效率为1 92lm/W,此时器件的发光亮度接近20cd/m2,色坐标为(x=0 317,y=0 328),非常接近白光等能点,是色度很好的白光。并且在很大范围内,色度随器件的驱动电压或电流变化不大,当驱动电压变化至15V时,J=232mA/cm2,色坐标变化至(x=0 338,y=0 353)。在电压为22V时,器件的亮度达到最大,为17000cd/m2。此外器件结构相对简单,器件制备的可重复性得到很大程度的改善。 展开更多
关键词 白光有机电致发光器件 制备 优化设计 发光效率
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High-definition colonoscopy with i-Scan:Better diagnosis for small polyps and flat adenomas 被引量:12
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作者 Pier Alberto Testoni Chiara Notaristefano +2 位作者 Cristian Vailati Milena Di Leo Edi Viale 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第37期5231-5239,共9页
AIM: To investigate if high-definition (HD) colonoscope with i-Scan gave a higher detection rate of mucosal le- sions vs standard white-light instruments. METHODS: Data were collected from the computer- ized datab... AIM: To investigate if high-definition (HD) colonoscope with i-Scan gave a higher detection rate of mucosal le- sions vs standard white-light instruments. METHODS: Data were collected from the computer- ized database of the endoscopy unit of our tertiary referral center. We retrospectively analyzed 1101 con- secutive colonoscopies that were performed over 1 year with standard white-light (n = 849) or HD+ with i-Scan (n = 252) instruments by four endoscopists, in an outpatient setting. Colonoscopy records included patients' main details and family history for colorectal cancer, indication for colonoscopy (screening, diagnos- tic or surveillance), type of instrument used (standard white-light or HD+ plus i-Scan), name of endoscopist and bowel preparation. Records for each procedure included whether the cecum was reached or not and the reason for failure, complications during or imme- diately after the procedure, and number, size, location and characteristics of the lesions. Polyps or protruding lesions were defined as sessile or pedunculated, and nonprotruding lesions were defined according to Paris classification. For each lesion, histological diagnosis was recorded. RESULTS: Eight hundred and forty-nine colonosco- pies were carried with the standard white-light video colonoscope and 252 with the HD+ plus i-Scan video colonoscope, The four endoscopists did 264, 300, 276 and 261 procedures, respectively; 21.6%, 24.0%, 21.7% and 24.1% of them with the HD+ plus i-Scan technique. There were no significant differences be- tween the four endoscopists in either the number of procedures done or the proportions of each imaging technique used. Both techniques detected one or more mucosal lesions in 522/1101 procedures (47.4%). The overall number of lesions recognized was 1266; 645 in the right colon and 621 in the left. A significantly higher number of colonoscopies recognized lesions in the HD+ plus i-Scan mode (171/252 = 67.9%) than with the standard white-light technique (4 展开更多
关键词 COLONOSCOPY High-definition+ with i-Scancolonoscopy white-light colonoscopy Colonic polyps Nonprotruding lesions Adenoma detection rate With-drawal time Surface enhancement Contrast enhance-ment Tone enhancement
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卤素灯照明光栅衍射共路数字全息显微定量相位成像 被引量:11
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作者 张佳恒 马利红 +1 位作者 李勇 金洪震 《中国激光》 EI CAS CSCD 北大核心 2018年第6期247-253,共7页
数字全息显微术是数字全息术和光学显微术相结合的定量相位成像技术。为克服高相干光源(激光)照明产生的散斑噪声和寄生条纹噪声,以及参物光路分离系统结构的不稳定性(易受外界震动干扰),实现了白光照明(卤素灯照明)的基于光栅衍射的共... 数字全息显微术是数字全息术和光学显微术相结合的定量相位成像技术。为克服高相干光源(激光)照明产生的散斑噪声和寄生条纹噪声,以及参物光路分离系统结构的不稳定性(易受外界震动干扰),实现了白光照明(卤素灯照明)的基于光栅衍射的共路离轴数字全息显微定量相位成像。首先基于理论分析和计算,得出系统可采用的光学元件参数和系统结构参数;然后建立了一套卤素灯照明的光栅衍射共路数字全息显微成像系统;最后对系统的成像准确度和时空噪声进行了测量。实验结果表明,该系统具有高准确度的成像性能,并具有非常高的时空敏感性(空间噪声为0.6nm,时间噪声为0.04nm)。 展开更多
关键词 全息 定量相位成像 白光 共路离轴 光栅衍射
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白光相移干涉法测量三维表面轮廓的算法及实现 被引量:4
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作者 刘泊 郑伟 +1 位作者 强锡富 蒋剑峰 《哈尔滨理工大学学报》 CAS 1999年第3期95-99,共5页
依据白光干涉理论,利用相移干涉法,研究了三维表面轮廓测量的原理与系统构成,讨论了白光相移干涉法测量三维表面轮廓的算法和数据处理的实现过程.实验结果表明,测量结果和数据处理都可精确地满足被测工件的要求.
关键词 相移干涉法 算法 白光干涉 表面轮廓 测量
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基于白光干涉原理的全光纤涡街流量测量方法 被引量:10
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作者 赵栋 吴红艳 唐璜 《仪器仪表学报》 EI CAS CSCD 北大核心 2011年第5期1038-1042,共5页
光纤涡街流量计在保留涡街类流量计优点的基础上,同时又具有光纤传感器无电磁辐射、抗电磁干扰、体积小、形状可变、环境适应性强等特殊优点,尤其是在易燃易爆环境中的应用,近年来得到了很大发展。文中介绍了一种新型的基于白光干涉原... 光纤涡街流量计在保留涡街类流量计优点的基础上,同时又具有光纤传感器无电磁辐射、抗电磁干扰、体积小、形状可变、环境适应性强等特殊优点,尤其是在易燃易爆环境中的应用,近年来得到了很大发展。文中介绍了一种新型的基于白光干涉原理的全光纤涡街流量测量方法及其结构,它只对动态参量响应,而屏蔽了静态、准静态干扰因素。基于该方法的流量计不仅具有光学干涉类传感器的高灵敏性,同时克服了传统干涉类传感器不稳定的缺点。最后,通过实验验证了该方法的可行性。 展开更多
关键词 涡街 流量计 光纤 白光 传感器
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Synthesis, structure and luminescent properties of yellow phosphor La3Si6N11 :Ce^3+ for high power white-LEDs 被引量:8
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作者 Fu Du Weidong Zhuang +5 位作者 Ronghui Liu Yuanhong Liu Wei Gao Xia Zhang Yuan Xue Hongrui Hao 《Journal of Rare Earths》 SCIE EI CAS CSCD 2017年第11期1059-1064,共6页
A series of high phase purity blue light excitable yellow-emitting LaSiN:xCephosphors were synthesized by the high temperature solid state reactions method. The structure and luminescent properties were investigated. ... A series of high phase purity blue light excitable yellow-emitting LaSiN:xCephosphors were synthesized by the high temperature solid state reactions method. The structure and luminescent properties were investigated. The phase structure was studied by means of X-ray diffraction, structures refinements and energy dispersive X-ray spectroscopy. The phosphors effectively excited by the light of450 nm and show intense yellow emission at 535 nm with FWHM of 115 nm corresponding to the5 d →~2 Fand 5 d →~2 Ftransitions of Ce. In addition,the optimized LaSiN:0.14 Ceexhibits a weak thermal quenching, which remains 98.2% of the initial emission intensity when heated to 200 ℃,the thermal quenching properties exhibit a modest decline when the temperature returned to room temperature. The above results indicate that LaSiN:Cecan be regarded as a high promising phosphor for applications in high power white-light LED. 展开更多
关键词 High phase purity La_3Si_6N_(11):Ce^(3+) Small thermal quenching High power white-light LED
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Comparative study on artificial intelligence systems for detecting early esophageal squamous cell carcinoma between narrow-band and white-light imaging 被引量:9
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作者 Bing Li Shi-Lun Cai +10 位作者 Wei-Min Tan Ji-Chun Li Ayimukedisi Yalikong Xiao-Shuang Feng Hon-Ho Yu Pin-Xiang Lu Zhen Feng Li-Qing Yao Ping-Hong Zhou Bo Yan Yun-Shi Zhong 《World Journal of Gastroenterology》 SCIE CAS 2021年第3期281-293,共13页
BACKGROUND Non-magnifying endoscopy with narrow-band imaging(NM-NBI)has been frequently used in routine screening of esophagus squamous cell carcinoma(ESCC).The performance of NBI for screening of early ESCC is,howeve... BACKGROUND Non-magnifying endoscopy with narrow-band imaging(NM-NBI)has been frequently used in routine screening of esophagus squamous cell carcinoma(ESCC).The performance of NBI for screening of early ESCC is,however,significantly affected by operator experience.Artificial intelligence may be a unique approach to compensate for the lack of operator experience.AIM To construct a computer-aided detection(CAD)system for application in NMNBI to identify early ESCC and to compare it with our previously reported CAD system with endoscopic white-light imaging(WLI).METHODS A total of 2167 abnormal NM-NBI images of early ESCC and 2568 normal images were collected from three institutions(Zhongshan Hospital of Fudan University,Xuhui Hospital,and Kiang Wu Hospital)as the training dataset,and 316 pairs of images,each pair including images obtained by WLI and NBI(same part),were collected for validation.Twenty endoscopists participated in this study to review the validation images with or without the assistance of the CAD systems.The diagnostic results of the two CAD systems and improvement in diagnostic efficacy of endoscopists were compared in terms of sensitivity,specificity,accuracy,positive predictive value,and negative predictive value.RESULTS The area under receiver operating characteristic curve for CAD-NBI was 0.9761.For the validation dataset,the sensitivity,specificity,accuracy,positive predictive value,and negative predictive value of CAD-NBI were 91.0%,96.7%,94.3%,95.3%,and 93.6%,respectively,while those of CAD-WLI were 98.5%,83.1%,89.5%,80.8%,and 98.7%,respectively.CAD-NBI showed superior accuracy and specificity than CAD-WLI(P=0.028 and P≤0.001,respectively),while CAD-WLI had higher sensitivity than CAD-NBI(P=0.006).By using both CAD-WLI and CAD-NBI,the endoscopists could improve their diagnostic efficacy to the highest level,with accuracy,sensitivity,and specificity of 94.9%,92.4%,and 96.7%,respectively.CONCLUSION The CAD-NBI system for screening early ESCC has higher accuracy and specificity than CAD-WLI.E 展开更多
关键词 Computer-aided detection Esophageal squamous cell carcinoma ENDOSCOPY SCREENING Narrow-band imaging white-light imaging
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Standard-definition White-light,High-definition White-light versus Narrow-band Imaging Endoscopy for Detecting Colorectal Adenomas:A Multicenter Randomized Controlled Trial
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作者 Chang-wei DUAN Hui-hong ZHAI +10 位作者 Hui XIE Xian-zong MA Dong-liang YU Lang YANG Xin WANG Yu-fen TANG Jie ZHANG Hui SU Jian-qiu SHENG Jun-feng XU Peng JIN 《Current Medical Science》 SCIE CAS 2024年第3期554-560,共7页
Objective This study aimed to compare the performance of standard-definition white-light endoscopy(SD-WL),high-definition white-light endoscopy(HD-WL),and high-definition narrow-band imaging(HD-NBI)in detecting colore... Objective This study aimed to compare the performance of standard-definition white-light endoscopy(SD-WL),high-definition white-light endoscopy(HD-WL),and high-definition narrow-band imaging(HD-NBI)in detecting colorectal lesions in the Chinese population.Methods This was a multicenter,single-blind,randomized,controlled trial with a non-inferiority design.Patients undergoing endoscopy for physical examination,screening,and surveillance were enrolled from July 2017 to December 2020.The primary outcome measure was the adenoma detection rate(ADR),defined as the proportion of patients with at least one adenoma detected.The associated factors for detecting adenomas were assessed using univariate and multivariate logistic regression.Results Out of 653 eligible patients enrolled,data from 596 patients were analyzed.The ADRs were 34.5%in the SD-WL group,33.5%in the HD-WL group,and 37.5%in the HD-NBI group(P=0.72).The advanced neoplasm detection rates(ANDRs)in the three arms were 17.1%,15.5%,and 10.4%(P=0.17).No significant differences were found between the SD group and HD group regarding ADR or ANDR(ADR:34.5%vs.35.6%,P=0.79;ANDR:17.1%vs.13.0%,P=0.16,respectively).Similar results were observed between the HD-WL group and HD-NBI group(ADR:33.5%vs.37.7%,P=0.45;ANDR:15.5%vs.10.4%,P=0.18,respectively).In the univariate and multivariate logistic regression analyses,neither HD-WL nor HD-NBI led to a significant difference in overall adenoma detection compared to SD-WL(HD-WL:OR 0.91,P=0.69;HD-NBI:OR 1.15,P=0.80).Conclusion HD-NBI and HD-WL are comparable to SD-WL for overall adenoma detection among Chinese outpatients.It can be concluded that HD-NBI or HD-WL is not superior to SD-WL,but more effective instruction may be needed to guide the selection of different endoscopic methods in the future.Our study’s conclusions may aid in the efficient allocation and utilization of limited colonoscopy resources,especially advanced imaging technologies. 展开更多
关键词 standard-definition white-light endoscopy high-definition white-light endoscopy narrow-band imaging colonoscopy colorectal cancer screening adenoma detection rate
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Topic highlight on texture and color enhancement imaging in gastrointestinal diseases
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作者 Osamu Toyoshima Toshihiro Nishizawa Keisuke Hata 《World Journal of Gastroenterology》 SCIE CAS 2024年第14期1934-1940,共7页
Olympus Corporation developed texture and color enhancement imaging(TXI)as a novel image-enhancing endoscopic technique.This topic highlights a series of hot-topic articles that investigated the efficacy of TXI for ga... Olympus Corporation developed texture and color enhancement imaging(TXI)as a novel image-enhancing endoscopic technique.This topic highlights a series of hot-topic articles that investigated the efficacy of TXI for gastrointestinal disease identification in the clinical setting.A randomized controlled trial demonstrated improvements in the colorectal adenoma detection rate(ADR)and the mean number of adenomas per procedure(MAP)of TXI compared with those of white-light imaging(WLI)observation(58.7%vs 42.7%,adjusted relative risk 1.35,95%CI:1.17-1.56;1.36 vs 0.89,adjusted incident risk ratio 1.48,95%CI:1.22-1.80,respectively).A cross-over study also showed that the colorectal MAP and ADR in TXI were higher than those in WLI(1.5 vs 1.0,adjusted odds ratio 1.4,95%CI:1.2-1.6;58.2%vs 46.8%,1.5,1.0-2.3,respectively).A randomized controlled trial demonstrated non-inferiority of TXI to narrow-band imaging in the colorectal mean number of adenomas and sessile serrated lesions per procedure(0.29 vs 0.30,difference for non-inferiority-0.01,95%CI:-0.10 to 0.08).A cohort study found that scoring for ulcerative colitis severity using TXI could predict relapse of ulcerative colitis.A cross-sectional study found that TXI improved the gastric cancer detection rate compared to WLI(0.71%vs 0.29%).A cross-sectional study revealed that the sensitivity and accuracy for active Helicobacter pylori gastritis in TXI were higher than those of WLI(69.2%vs 52.5%and 85.3%vs 78.7%,res-pectively).In conclusion,TXI can improve gastrointestinal lesion detection and qualitative diagnosis.Therefore,further studies on the efficacy of TXI in clinical practice are required. 展开更多
关键词 Endoscopy Texture and color enhancement imaging white-light imaging Narrow-band imaging Colorectal neoplasm Gastric cancer Adenoma Ulcerative colitis Helicobacter infections Colonoscopy
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Recent Developments in Fiber Optic Spectral White-Light Interferometry 被引量:6
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作者 Yi JIANG Wenhui DING 《Photonic Sensors》 SCIE EI 2011年第1期62-71,共10页
Recent developments in spectral white-light interferometry(WLI)are reviewed.Firstly,the techniques for obtaining optical spectrum are introduced.Secondly,some novel measurement techniques are reviewed,including the im... Recent developments in spectral white-light interferometry(WLI)are reviewed.Firstly,the techniques for obtaining optical spectrum are introduced.Secondly,some novel measurement techniques are reviewed,including the improved peak-to-peak WLI,improved wavelength-tracking WLI,Fourier transform WLI,and 3×3 coupler based WLI.Furthermore,a hybrid measurement for the intensity-type sensors,interferometric sensors,and fiber Bragg grating sensors is achieved.It is shown that these developments have assisted in the progress of WLI. 展开更多
关键词 Optical fiber sensors white-light interferometry optical path difference fiber Fabry-Perot tunable filter extrinsic Fabry-Perot interferometer
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Efficient blue-light-excitable copper(Ⅰ) coordination network phosphors for high-performance white LEDs
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作者 Pingping Wang Huixian Miao +5 位作者 Kechuan Sheng Bin Wang Fan Feng Xuankun Cai Wei Huang Dayu Wu 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第4期511-515,共5页
The blue-light-excitable phosphors play a crucial role in the high-performance white LEDs. Here, we report on two new Cu(Ⅰ) coordination network materials as yellow-emitting phosphors prepared by suitably expanded π... The blue-light-excitable phosphors play a crucial role in the high-performance white LEDs. Here, we report on two new Cu(Ⅰ) coordination network materials as yellow-emitting phosphors prepared by suitably expanded π-conjugated triazole ligands. Upon blue-light irradiation, these complexes exhibit efficient solid-state emission and enhanced photostability. Through incorporating the yellow phosphor and a commercial blue-green powder(BaSi_(2)N_(2)O_(2):Eu^(2+)) with a blue LED chip, the phosphor-converted LED devices display remarkable white emission properties. The experimental results demonstrate that the Cu(Ⅰ)coordination network materials function as promising blue-light excitable phosphors with great application potential for full-spectrum white LEDs. 展开更多
关键词 Metal-organic framework Coordination polymer PHOTOLUMINESCENCE Phosphor material white-light LED Phosphor-converted LED
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Synthesis and luminescence properties of KCaPO_4:Eu^(2+),Tb^(3+),Mn^(2+) for white-light-emitting diodes(WLED) 被引量:4
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作者 方宏威 黄山 +3 位作者 韦先涛 段昌奎 尹民 陈永虎 《Journal of Rare Earths》 SCIE EI CAS CSCD 2015年第8期825-829,共5页
In order to obtain a single-host white-light phosphor, a series of KCaPO4 powder samples tri-doped with Eu2+, Tb3+ and Mn2+ were synthesized via high-temperature solid-state reaction method. Their structural and lu... In order to obtain a single-host white-light phosphor, a series of KCaPO4 powder samples tri-doped with Eu2+, Tb3+ and Mn2+ were synthesized via high-temperature solid-state reaction method. Their structural and luminescence properties were investigated. Under proper ultraviolet excitation (255-405 urn), white light was obtained, consisting of blue, green and red emissions stemming from Eu2+, Th3+, Mn2+ ions respectively. The temperature stability of our sample was analyzed by studying the variation tendeney of CIE chromaticity coordinates at different temperatures. The results indicated that this phosphor could yield good color stability when utilized in WLED. 展开更多
关键词 single-phase white-light phosphor photoluminescence energy transfer color stability CIE chromaticity coordinates rare earths
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Efficacy of image-enhanced endoscopy for colorectal adenoma detection:A multicenter,randomized trial 被引量:1
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作者 Zhi-Peng Qi En-Pan Xu +19 位作者 Dong-Li He Yan Wang Bai-Sheng Chen Xue-Si Dong Qiang Shi Shi-Lun Cai Qi Guo Ni Li Xing Li Hai-Yan Huang Bing Li Di Sun Jian-Guang Xu Zhang-Han Chen Ayimukedisi Yalikong Jin-Yi Liu Zhen-Tao Lv Jian-Min Xu Ping-Hong Zhou Yun-Shi Zhong 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第5期878-891,共14页
BACKGROUND Improved adenoma detection at colonoscopy has decreased the risk of developing colorectal cancer.However,whether image-enhanced endoscopy(IEE)further improves the adenoma detection rate(ADR)is controversial... BACKGROUND Improved adenoma detection at colonoscopy has decreased the risk of developing colorectal cancer.However,whether image-enhanced endoscopy(IEE)further improves the adenoma detection rate(ADR)is controversial.AIM To compare IEE with white-light imaging(WLI)endoscopy for the detection and identification of colorectal adenoma.METHODS This was a multicenter,randomized,controlled trial.Participants were enrolled between September 2019 to April 2021 from 4 hospital in China.Patients were randomly assigned to an IEE group with WLI on entry and IEE on withdrawal(n=2113)or a WLI group with WLI on both entry and withdrawal(n=2098).The primary outcome was the ADR.The secondary endpoints were the polyp detection rate(PDR),adenomas per colonoscopy,adenomas per positive colonoscopy,and factors related to adenoma detection.RESULTS A total of 4211 patients(966 adenomas)were included in the analysis(mean age,56.7 years,47.1%male).There were 2113 patients(508 adenomas)in the IEE group and 2098 patients(458 adenomas)in the WLI group.The ADR in two group were not significantly different[24.0%vs 21.8%,1.10,95%confidence interval(CI):0.99-1.23,P=0.09].The PDR was higher with IEE group(41.7%)than with WLI group(36.1%,1.16,95%CI:1.07-1.25,P=0.01).Differences in mean withdrawal time(7.90±3.42 min vs 7.85±3.47 min,P=0.30)and adenomas per colonoscopy(0.33±0.68 vs 0.28±0.62,P=0.06)were not significant.Subgroup analysis found that with narrowband imaging(NBI),between-group differences in the ADR,were not significant(23.7%vs 21.8%,1.09,95%CI:0.97-1.22,P=0.15),but were greater with linked color imaging(30.9%vs 21.8%,1.42,95%CI:1.04-1.93,P=0.04).the second-generation NBI(2G-NBI)had an advantage of ADR than both WLI and the first-generation NBI(27.0%vs 21.8%,P=0.01;27.0%vs 21.2.0%,P=0.01).CONCLUSION This prospective study confirmed that,among Chinese,IEE didn’t increase the ADR compared with WLI,but 2G-NBI increase the ADR. 展开更多
关键词 ENDOSCOPY Image-enhanced endoscopy Adenoma detection rate white-light imaging Narrowband imaging
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Recent progress in ICF target fabrication at RCLF 被引量:5
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作者 Kai Du Meifang Liu +3 位作者 Tao Wang Xiaoshan He Zongwei Wang Juan Zhang 《Matter and Radiation at Extremes》 SCIE EI CAS 2018年第3期135-144,共10页
Target is one of the essential parts in inertial confinement fusion(ICF)experiments.To ensure the symmetry and hydrodynamic stability in the implosion,there are stringent specifications for the target.Driven by the ne... Target is one of the essential parts in inertial confinement fusion(ICF)experiments.To ensure the symmetry and hydrodynamic stability in the implosion,there are stringent specifications for the target.Driven by the need to fabricate the target required by ICF experiments,a series of target fabrication techniques,including capsule fabrication techniques and the techniques of target characterization and assembly,are developed by the Research Center of Laser Fusion(RCLF),China Academy of Engineering Physics(CAEP).The capsule fabrication techniques for preparing polymer shells,glow discharge polymer(GDP)shells and hollow glass micro-sphere(HGM)are studied,and the techniques of target characterization and assembly are also investigated in this paper.Fundamental research about the target fabrication is also done to improve the quality of the target.Based on the development of target fabrication techniques,some kinds of target have been prepared and applied in the ICF experiments. 展开更多
关键词 Capsule fabrication Target characterization and assembly Microencapsulation technique Depolymerizable mandrel technique white-light interferometry
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Organic white-light sources:Multiscale construction of organic luminescent materials from molecular to macroscopic level 被引量:4
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作者 Song Chen Xue-Dong Wang +3 位作者 Ming-Peng Zhuo Qiang Lv Jing-Feng Liu Liang-Sheng Liao 《Science China Chemistry》 SCIE EI CSCD 2022年第4期740-745,共6页
Organic luminescent materials play an integral role in the optoelectronic applications of displays and solid-state lighting.Nevertheless, high-performance organic luminescent materials require the efficient combinatio... Organic luminescent materials play an integral role in the optoelectronic applications of displays and solid-state lighting.Nevertheless, high-performance organic luminescent materials require the efficient combination of two or more kinds of materials, which is extremely difficult owing to the completely different self-assembly behaviors of multicomponent molecules.Herein, based on a broad scale from the molecular, micro-/nano-scale, and macroscopic levels, we successfully demonstrate the multiscale construction of organic luminescent microwires of cocrystals, solid solutions, and core-shell microstructures. Through the wide selection of electron donor/acceptor pairs, a series of color-tunable charge-transfer(CT) cocrystals are formed via the intermolecular cooperative self-assembly process. On this basis, the high structural compatibility and perfect lattice mismatching(~1.1%) of cocrystals are critical factors that facilitate the combination of dissimilar materials to form solid solutions and core/shell microwires. Significantly, because of the full-spectrum light transport from 400 to 800 nm, the nano-micro-scaled solid solution microwires act as microscale white-light sources [CIE(0.32, 0.36)]. Meanwhile, the macroscopic-scale core/shell organic-microwires demonstrate tunable white-light emission with a high color-rendering index(CRI) of 83, whose CIE coordinates span from(0.37, 0.39) to(0.40, 0.31). Therefore, our work provides a feasible approach to the multiscale synthesis of novel luminescent organic semiconductor materials, which could lay a solid foundation for organic optoelectronics. 展开更多
关键词 noncovalent interaction multiscale self-assembly core/shell solid solution white-light emission
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Predictably synthesizing a library of white-light-emitting perovskites 被引量:1
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作者 Ludan Niu Lili Zhao +6 位作者 Deyu Li Qian Chen Mingming Zhang Jing Luan Lei Wang Weigao Xu Jun Xing 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第3期760-767,共8页
The low-dimensional organic-inorganic halide perovskites with self-trapped exciton emission have promising prospects for single-phase white-light emitters. However, so far, these broadband white-light-emitting(BWLE) p... The low-dimensional organic-inorganic halide perovskites with self-trapped exciton emission have promising prospects for single-phase white-light emitters. However, so far, these broadband white-light-emitting(BWLE) perovskites were synthesized by trial-and-error testing spacing molecules. Here, we developed a steric hindrance regulation strategy to predictably synthesize BWLE perovskites. The molecules containing C–C(–NH_(2))–C groups were introduced into low-dimensional perovskites, which brings a large steric hindrance in-plane orientation. The bigger C–C(–NH_(2))–C bond angle would induce larger structural distortion in perovskites, which leads to the higher rate of self-trapping of excitons and the deeper self-trapping depth. The photoluminescence spectra of the synthesized perovskites can cover the cool-to-warm white light region. Overall, we fabricated a material library consisting of 40 kinds of BWLE compounds according to this strategy. Our findings develop a general strategy to synthesize BWLE perovskites and offer a material platform for optoelectronic applications. 展开更多
关键词 white-light emission halide perovskite steric hindrance TWO-DIMENSIONAL
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Ambient White-Light Afterglow Emission Based on Triplet-to-Singlet Förster Resonance Energy Transfer 被引量:3
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作者 Huiqiang Gui Zizhao Huang +1 位作者 Zhiyi Yuan Xiang Ma 《CCS Chemistry》 CAS 2022年第1期173-181,共9页
Compared with fluorescent materials,metal-free organic environmental afterglow materials,with larger Stokes shifts,longer lifetimes,higher S/N ratios,and sensitivities,present potential in new applications.However,ach... Compared with fluorescent materials,metal-free organic environmental afterglow materials,with larger Stokes shifts,longer lifetimes,higher S/N ratios,and sensitivities,present potential in new applications.However,achieving air stability and long lifetime organic afterglow systems with tunable emission color still remains a challenge.Herein,we have designed and synthesized luminescent copolymers exhibiting afterglow emission with tunability including white-light afterglow with considerable quantum yield[Commission Internationale de l’Eclairage(CIE)coordinates(0.32,0.33),ΦP=11%]in the amorphous state through the rarely reported triplet-to-singlet Förster resonance energy transfer(TS-FET).Also,they can emit different colors under UV light,including white-light[CIE coordinates(0.31,0.33),ΦPl=27%].This strategy was achieved by copolymerizing two simple-structured single-benzene-based compounds with acrylamide(AM)in different ratios.In addition,these materials can also be employed as a safety ink for paper paving the way for long lifetime luminescent material applications. 展开更多
关键词 triplet-to-singlet Förster resonance energy transfer fluorescence metal-freeorganic afterglow white-light afterglow white photoluminescence
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Study on white-light emission and light-emitting mechanism of hydrothermally synthesized YVO_4:1 mol.%Dy^(3+),x mol.%Eu^(3+) phosphor powders 被引量:3
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作者 刘红涛 梁艳 +1 位作者 郜小勇 张飒 《Journal of Rare Earths》 SCIE EI CAS CSCD 2016年第2期113-117,共5页
White light-emitting YVO4:1 mol.%Dy3+,x mol.%Eu3+ phosphor powders with order morphology and well crystallization were hydrothermally synthesized at 180°C. The microstructure, white-light emission, and light-emit... White light-emitting YVO4:1 mol.%Dy3+,x mol.%Eu3+ phosphor powders with order morphology and well crystallization were hydrothermally synthesized at 180°C. The microstructure, white-light emission, and light-emitting mechanism of the powders were carefully studied using X-ray diffractometry, scanning electron microscopy and photoluminescence spectra. The excitation and emission spectra of the phosphor powders indicated the coexistence of efficient energy transfer from Eu3+ to Dy3+ and inefficient en-ergy transfer from Dy3+ to Eu3+ besides the energy transfer from VO43– to Eu3+. Increasing the Eu3+ concentration initially enhanced and then weakened the luminescent intensity of Dy3+. The white-light emissions of YVO4:1 mol.%Dy3+,xmol.%Eu3+ phosphor pow-ders were both related to the energy transfer between VO43– and Dy3+/Eu3+, as well as between Eu3+ and Dy3+. The inefficient energy transfer from Dy3+ to Eu3+ was first found. 展开更多
关键词 YVO4 Dy3+ Eu3+ phosphor powders hydrothermal synthesis white-light emission photoluminescence energy transfer rare earths
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A novel intelligent chromo capsule endoscope for the diagnosis of neoplastic lesions in the gastrointestinal tract
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作者 Huiying Shi Suya Pang +3 位作者 Fanhua Ming Tianyi Yangdai Shuxin Tian Rong Lin 《Gastroenterology Report》 SCIE CSCD 2023年第1期291-299,共9页
Background:Chromoendoscopy has not been fully integrated into capsule endoscopy.This study aimded to develop and validate a novel intelligent chromo capsule endoscope(ICCE).Methods:The ICCE has two modes:a white-light... Background:Chromoendoscopy has not been fully integrated into capsule endoscopy.This study aimded to develop and validate a novel intelligent chromo capsule endoscope(ICCE).Methods:The ICCE has two modes:a white-light imaging(WLI)mode and an intelligent chromo imaging(ICI)mode.The performance of the ICCE in observing colors,animal tissues,and early gastrointestinal(GI)neoplastic lesions in humans was evaluated.Images captured by the ICCE were analysed using variance of Laplacian(VoL)values or image contrast evaluation.Results:For color observation,conventional narrow-band imaging endoscopes and the ICI mode of the ICCE have similar spectral distributions.Compared with the WLI mode,the ICI mode had significantly higher VoL values for animal tissues(2.15461.044 vs 3.80061.491,P=0.003),gastric precancerous lesions and early gastric cancers(2.24260.162 vs 6.64260.919,P<0.001),and colon tumors(3.89661.430 vs 11.88267.663,P<0.001),and significantly higher contrast for differentiating tumor and non-tumor areas(0.06960.046 vs 0.14460.076,P=0.005).More importantly,the sensitivity,specificity,and accuracy of the ICI mode for early GI tumors were 95.83%,91.67%,and 94.64%,respectively,which were significantly higher than the values of the WLI mode(78.33%[P<0.001],77.08%[P=0.01],and 77.98%[P<0.001],respectively).Conclusions:We successfully integrated ICI into the capsule endoscope.The ICCE is an innovative and useful tool for differential diagnosis based on contrast-enhanced images and thus has great potential as a superior diagnostic tool for early GI tumor detection. 展开更多
关键词 capsule endoscopy CHROMOENDOSCOPY intelligent chromo capsule endoscope white-light imaging intelligent chromo imaging
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Spherical lanthanide nanoclusters toward white-light emission and cell membrane imaging
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作者 Hai-Ling Wang Zhiqiang Ni +5 位作者 Ze-Yu Ruan Zhong-Hong Zhu Pei-Yu Liao Guangxue Feng Jian-Hua Jia Ming-Liang Tong 《Nano Research》 SCIE EI CSCD 2023年第8期11495-11502,共8页
Lanthanide doping is an effective strategy for modulating the emission of emitters.Herein,by changing the cluster composition to control the energy transfer pathway,the application potential of high-nuclearity lanthan... Lanthanide doping is an effective strategy for modulating the emission of emitters.Herein,by changing the cluster composition to control the energy transfer pathway,the application potential of high-nuclearity lanthanide cluster(HLC)as white-light emitter has been confirmed for the first time.Specifically,by precisely controlling the proportion of GdIII,TbIII,and EuIII ions in reactants,we obtained a spherical heterotrimetallic nanocluster Gd_(10)Tb_(12)Eu_(10),a white-light emitter with quantum yield(QY)of 12.58%and lifetime of 327.14μs.High-resolution electrospray ionization mass spectrometry(HRESI-MS)demonstrates that homometallic nanoclusters Ln_(32)(Ln=Gd,Tb,and Eu)are tetracationic clusters and are highly stable in solution.The peripheral dense organic ligands provide a protective layer for the cluster core,which improves the stability of Ln_(32) in aqueous solution,avoids the contact between metal centers and bioactive molecules,and greatly reduces the biological toxicity.In cell imaging experiments,cationic clusters Ln_(32) are mainly localized on the cell membrane with negative charge distribution.As far as we know,this is the first time that spherical lanthanide nanoclusters have been used for membrane imaging of living cell,opening the door for the application of HLCs in biological imaging. 展开更多
关键词 spherical lanthanide clusters white-light emission high stability low toxicity cell membrane imaging
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