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Early Cretaceous Climate Changes Recorded in Magnetic Susceptibility and Color Index Variations of the Lower Liupanshan Group, Central China 被引量:4
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作者 DAI Shuang ZHU Qiang +9 位作者 HUANG Yongbo DA SILVA Anne-Christine ZHAO Jie LIU Junwei KONG Li PENG Dongxiang LUO Lingling YAN Ningyun WANG Wenjie ZHANG Xiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第3期1011-1023,共13页
This study carried out comprehensive analysis on sedimentology, magnetic susceptibility (7of) and color data of the continental sediments of the Liupanshan Group in Central China so as to obtain climatic change info... This study carried out comprehensive analysis on sedimentology, magnetic susceptibility (7of) and color data of the continental sediments of the Liupanshan Group in Central China so as to obtain climatic change information during the 129.14-122.98 Ma interval. Based on the results of the Xlf and of the redness (a*), the section can be divided into two segments: (1) 129.14-126.3 Ma, with the lowest Xlf values and strongly variable relatively high values of redness and (2) 126.3-122.98 Ma, with high Elf values and relatively low redness. Analysis of the lithology and facies as well as the magnetic minerals and their contents points to a detrital origin of the magnetic minerals and this allow us to interpret the relationship between magnetic susceptibility variations and climate changes. Our study shows that the climate was significantly dry and hot during the whole studied interval although the interval between 126.3 Ma and 122.98 was a little bit cooler with increased humidity. 展开更多
关键词 magnetic susceptibility color index climate change Liupanshan Group Early Cretaceous
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A novel green phosphor Ba_(2)Sc_(2)((BO_(3))_(2)B_(2)O_(5)):Ce^(3+)for high color rendering index full-spectrum lighting and low-temperature sensors
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作者 Pan Liang Hongshu Zhang +7 位作者 Yingying Xue Saying Li Hongsheng Huang Xin Li Xuxiang Lin Yuxin Zhang Lianqing Li Zhihong Liu 《Journal of Rare Earths》 2025年第6期1150-1160,I0003,共12页
The utilization of phosphors that achieve full-spectrum lighting has emerged as a prevailing trend in the advancement of white light-emitting diode(WLED)lighting.In this study,we successfully prepared a novel green ph... The utilization of phosphors that achieve full-spectrum lighting has emerged as a prevailing trend in the advancement of white light-emitting diode(WLED)lighting.In this study,we successfully prepared a novel green phosphor Ba_(2)Sc_(2)((BO_(3))_(2)B_(2)O_(5)):Ce^(3+)(BSBO:Ce^(3+))that can be utilized for full-spectrum lighting and low-temperature sensors.BSBO:Ce^(3+)exhibits a broad-band excitation spectrum centered at 410 nm,and a broad-band emission spectrum centered at 525 nm.The internal and external quantum efficiencies of BSBO:Ce^(3+)are 99%and 49%,respectively.The thermal stability of BSBO:Ce^(3+)can be improved by substituting partial Sc atoms with smaller cations.The thermal quenching mechanism of BSBO:Ce^(3+)and the lattice occupancy of Ce ions in BSBO are discussed in detail.Furthermore,by combining the green phosphor BSBO:Ce^(3+),the commercial blue phosphor and the red phosphor on a 405 nm chip,a white light source was obtained with a high average color rendering index(CRI)of 96.6,a low correlated color temperature(CCT)of 3988 K,and a high luminous efficacy of 88.0 Im/W.The lu-minous efficacy of the WLED exhibits negligible degradation during the 1000 h light aging experiment.What's more,an emission peak at 468 nm appears when excited at 352 nm and 80 K,however,the relative intensity of the peaks at 468 and 525 nm gradually weakens with increasing temperature,indicating the potential of this material as a low-temperature sensor. 展开更多
关键词 Green phosphor Ba_(2)Sc_(2)(BO_(3)_(2)B_(2)O_(5)):Ce^(3+) Fullspectrum lighting Low-temperature sensor High color rendering index Rare earths
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Use of electrochemical color index as emerging analytical method for evaluating the quality of Tequila 100%agave
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作者 Walter M.Warren-Vega Rocío Fonseca-Aguiñaga +1 位作者 Linda VGonzález-Gutiérrez Luis A.Romero-Cano 《Food Bioscience》 2023年第6期2429-2436,共8页
Physicochemical and electrochemical characterization of Tequila 100%agave and its classes was carried out to obtain fundamental information that allows the design of specific electrodes useful as electrochemical senso... Physicochemical and electrochemical characterization of Tequila 100%agave and its classes was carried out to obtain fundamental information that allows the design of specific electrodes useful as electrochemical sensors for evaluating the quality of alcoholic beverages.The physicochemical characterization consisted of gas and liquid chromatography,and atomic absorption spectroscopy studies.It was observed that the chromatographic parameters declared by the current Mexican official standards must be complemented with another analytical technique to differentiate between Tequila and problem samples.The above results relate satisfactorily to electrochemical studies.The differential pulse voltammograms of the Tequila 100%agave samples in their different classes showed three characteristic signals:i)-0.05 V vs.Ag/AgCl(sat)attributable to the reduction of Cu^(2+)to Cu^(0)present in the sample;ii)0.34 V vs.Ag/AgCl_((sat))related to the polyphenolic fraction that has antioxidant activity;therefore to the oxidation of organic compounds that contain the catechol group,and iii)0.50 V vs.Ag/AgCl_((sat))due to the oxidation of the flavonoid group which can be related to the maturation process of the beverage;with this results,electrochemical color index was determined for Tequila,problem samples and alcoholic beverages obtained from other agave species. 展开更多
关键词 Tequila 100%agave Electrochemical color index Oxidation of total polyphenols Oxidation of total flavonoids
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Very-High Color Rendering Index Hybrid White Organic Light-Emitting Diodes with Double Emitting Nanolayers 被引量:3
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作者 Baiquan Liu Miao Xu +6 位作者 Lei Wang Hong Tao Yueju Su Dongyu Gao Linfeng Lan Jianhua Zou Junbiao Peng 《Nano-Micro Letters》 SCIE EI CAS 2014年第4期335-339,共5页
A very-high color rendering index white organic light-emitting diode(WOLED) based on a simple structure was successfully fabricated. The optimized device exhibits a maximum total efficiency of 13.1 and 5.4 lm/W at 1,0... A very-high color rendering index white organic light-emitting diode(WOLED) based on a simple structure was successfully fabricated. The optimized device exhibits a maximum total efficiency of 13.1 and 5.4 lm/W at 1,000 cd/m2. A peak color rendering index of 90 and a relatively stable color during a wide range of luminance were obtained. In addition, it was demonstrated that the 4,40,400-tri(9-carbazoyl) triphenylamine host influenced strongly the performance of this WOLED.These results may be beneficial to the design of both material and device architecture for high-performance WOLED. 展开更多
关键词 White light HYBRID color rendering index Organic light-emitting diodes Double emitting nanolayers
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Effect of light-emitting diodes with different color rendering indexes on the ocular tissues of rat 被引量:2
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作者 Wen-Yi Chen Kun-Hong Xiao +5 位作者 Rong Lin Ze-Ren Qiu Ya-Min Chen Ze-Qun Lin Xiu-Bin Ke Yan Huang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2022年第7期1035-1043,共9页
AIM:To compare the damage of light-emitting diodes(LEDs)with different color rendering indexes(CRIs)to the ocular surface and retina of rats.METHODS:Totally 20 Sprague-Dawley(SD)rats were randomly divided into four gr... AIM:To compare the damage of light-emitting diodes(LEDs)with different color rendering indexes(CRIs)to the ocular surface and retina of rats.METHODS:Totally 20 Sprague-Dawley(SD)rats were randomly divided into four groups:the first group was normal control group without any intervention,other three groups were exposed by LEDs with low(LED-L),medium(LED-M),and high(LED-H)CRI respectively for 12 h a day,continuously for 4 wk.The changes in tear secretion(Schirmer I test,SIt),tear film break-up time(BUT),and corneal fluorescein sodium staining(CFS)scores were compared at different times(1 d before experiment,2 and 4 wk after the experiment).The histopathological changes of rat lacrimal gland and retina were observed at 4 wk,and the expressions of tumor necrosis factor-α(TNF-α)and interleukin-6(IL-6)in lacrimal gland were detected by immunofluorescence method.RESULTS:With the increase of light exposed time,the CFS value of each light exposed group continued to increase,and the BUT and SIt scores continued to decrease,which were different from the control group,and the differences between the light exposed groups were statistically significant.Hematoxylin-eosin(HE)results showed that the lacrimal glands of each exposed group were seen varying degrees of acinar atrophy,vacuoledistribution,increasing of eosinophil granules,etc.;the retina showed obvious reduction of photoreceptor cell layer and changes in retinal thickness;LED-L group has the most significant change in all tests.Immunofluorescence suggested that the positive expressions of TNF-αand IL-6 in the lacrimal glands of each exposed group were higher than those of the control group.CONCLUSION:LED exposure for 4 wk can cause the pathological changes of lacrimal gland and retina of rats,and increase the expression of TNF-αand IL-6 in lacrimal gland,the degree of damage is negatively correlated with the CRI. 展开更多
关键词 light emitting diodes lacrimal gland RETINA dry eye color rendering indexes SPECTRUM
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High color rendering index white organic light-emitting diode using levofloxacin as blue emitter 被引量:1
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作者 苗艳勤 高志翔 +5 位作者 张爱琴 李源浩 王华 贾虎生 刘旭光 Tsuboi Taiju 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第5期577-582,共6页
Levofloxacin (LOFX), which is well-known as an antibiotic medicament, was shown to be useful as a 452-nm blue emitter for white organic light-emitting diodes (OLEDs). In this paper, the fabricated white OLED conta... Levofloxacin (LOFX), which is well-known as an antibiotic medicament, was shown to be useful as a 452-nm blue emitter for white organic light-emitting diodes (OLEDs). In this paper, the fabricated white OLED contains a 452-nm blue emitting layer (thickness of 30 nm) with 1 wt% LOFX doped in CBP (4,4'-bis(carbazol-9-yl)biphenyl) host and a 584-nm orange emitting layer (thickness of 10 nm) with 0.8 wt% DCJTB (4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7- tetramethyljulolidin-4-yl-vinyl)-4H-pyran) doped in CBE which are separated by a 20-nm-thick buffer layer of TPBi (2,2',2"-(benzene-1,3,5-triyl)-tri(1-phenyl-lH-benzimidazole). A high color rendering index (CRI) of 84.5 and CIE chromaticity coordinates of (0.33, 0.32), which is close to ideal white emission CIE (0.333, 0.333), are obtained at a bias voltage of 14 V. Taking into account that LOFX is less expensive and the synthesis and purification technologies of LOFX are mature, these results indicate that blue fluorescence emitting LOFX is useful for applications to white OLEDs although the maximum current efficiency and luminance are not high. The present paper is expected to become a milestone to using medical drug materials for OLEDs. 展开更多
关键词 LEVOFLOXACIN blue organic light emitting diodes white organic light-emitting diodes high color rendering index
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High efficient and high color rendering index white organic light-emitting diodes
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作者 张民艳 尚玉柱 +3 位作者 徐红 吕燕芳 于建宁 魏斌 《Journal of Shanghai University(English Edition)》 CAS 2011年第4期252-255,共4页
We have fabricated high-efficient white organic light-emitting diodes (WOLEDs) using two types of electron transport materials with different electron mobility. The effect of the electron mobility on the device perf... We have fabricated high-efficient white organic light-emitting diodes (WOLEDs) using two types of electron transport materials with different electron mobility. The effect of the electron mobility on the device performance is discussed. In addition, to generate the desired white emission and high color rendering index, we perform the structure design of OLED, in which the functions of co-host of blue and green dopants on chromatic-stability are investigated. Experimental results find that the maximum color rendering index reaches as high as 91 at the voltage of 8 V. 展开更多
关键词 white organic light emitting diodes (WOLEDs) charge balance energy transfer color rendering index
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Fabrication of High Color Rendering Index White Light Emitting Diodes from Gold Nanoclusters
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作者 Yeeu-Chang Lee Chieh Chen +2 位作者 Cheng-An J. Lin Cheng-Yi Huang Chia-Hui Lin 《Optics and Photonics Journal》 2023年第11期243-250,共8页
We demonstrated gold nanoclusters as color tunable emissive light converters for the application of white light emitting diodes (WLEDs). A blue LED providing 460 nm to excite gold nanoclusters mixed with UV curable ma... We demonstrated gold nanoclusters as color tunable emissive light converters for the application of white light emitting diodes (WLEDs). A blue LED providing 460 nm to excite gold nanoclusters mixed with UV curable material generates broad bandwidth emission at the visible range. Increasing the amount of gold nanoclusters, the correlated color temperature of WLEDs tuned from cold white to warm white, and also results in the variation of color rendering index (CRI). The highest CRI in the experiment is 92. 展开更多
关键词 Gold Nanocluster White Light Emitting Diodes color Rendering index color Temperature
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最大度为4的无爪图的强边染色
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作者 丁佩瑶 陈东 +1 位作者 王侃 王维凡 《数学进展》 北大核心 2026年第2期257-262,共6页
图G的强边色数χ'_(s)(G)是使得G的边集能分解为k个导出匹配的最小整数k.本文证明了每个最大度为4的无爪图G满足χ'_(s)(G)≤17,且构造了一个强边色数为14的4-正则无爪图.
关键词 无爪图 强边染色 强边色数 最大度
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多种颜色指数对不同光线场景下水稻行分割的比较研究
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作者 钱美玲 魏新华 +2 位作者 朱耀辉 宋琦 孟宪博 《农机化研究》 北大核心 2026年第7期86-93,116,共9页
稻田图像分割是视觉导航中导航线识别的关键技术,但光照变化、叶片形态和水面反光等因素对分割精度影响显著。为此,选取RGB、Lab、XYZ、HSI、YCbCg等颜色空间的21种颜色指数与改进的超绿指数,结合Otsu法分割水稻苗期、分蘖期和分蘖后期... 稻田图像分割是视觉导航中导航线识别的关键技术,但光照变化、叶片形态和水面反光等因素对分割精度影响显著。为此,选取RGB、Lab、XYZ、HSI、YCbCg等颜色空间的21种颜色指数与改进的超绿指数,结合Otsu法分割水稻苗期、分蘖期和分蘖后期的图像,以探索在水稻行间不同作业场景下图像分割对应的最优颜色。结果表明,不同生长阶段最优颜色指数不同:苗期ExG可增强绿色对比度,有效抑制水面镜面反射,分蘖期根据ExG调整后的ExGPro能适应叶片表面反射,分蘖后期Cg分量有效抑制大面积叶面反射;此外,光照方向显著影响分割精度。对于不同场景采用对应最优颜色指数,相较于不同生长阶段的固定指数方案,分割精度提高2.0%~2.5%,有效减少了环境噪声的干扰。研究还探讨了计算复杂度问题,并建议优化轻量级颜色指数组合,以平衡精度与实时性。研究成果可推广至其他作物视觉对行导航中的图像分割。 展开更多
关键词 水稻图像分割 颜色指数 机器视觉 导航线识别 颜色空间 OTSU法
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2025年中国舞台影视灯光调研分析报告——常规灯具·特效器篇
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作者 吴剑敏 白文国 +2 位作者 代永峰 周闻 王京池 《照明工程学报》 2026年第1期159-166,共8页
本文根据中国照明学会舞台电影电视照明专业委员会2025年的调研情况,对常规灯具的光色光质提升、智能色彩管理技术的运用、光色校正与灯光设备色域拓展、色温稳定性、显色性提升、光源一致性,以及特效器的新技术新理念进行总结与归纳。
关键词 常规灯具 光色品质 色彩管理 光色校正 色温 显色指数 特效器
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混池样本数量对辣椒果色基因定位的影响
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作者 黄汕 盘祥 +3 位作者 陈潇 常静静 张白鸽 宋钊 《中国农学通报》 2026年第1期37-42,共6页
为明确辣椒BSA分析中适宜的DNA混池样本数量及可靠关联算法,本研究以青熟期淡黄果色(CSJ009)和绿果色(CSJ010)辣椒自交系构建的F_(2)分离群体为材料,分别选取30株(2019年群体,220株)和50株(2021年群体,788株)极端表型单株构建DNA混池,... 为明确辣椒BSA分析中适宜的DNA混池样本数量及可靠关联算法,本研究以青熟期淡黄果色(CSJ009)和绿果色(CSJ010)辣椒自交系构建的F_(2)分离群体为材料,分别选取30株(2019年群体,220株)和50株(2021年群体,788株)极端表型单株构建DNA混池,进行全基因组重测序(WGRS)及BSA分析,比较SNP-index与ED 2种算法的定位效果。结果表明,50样本混池测序深度(平均50.92×)高于30样本混池(35×以上),Q_(30)质量值(94.71%以上)更优,SNP与InDel标记检测错误率更低,但定位结果更复杂;SNP-index算法在50样本混池的99%置信水平下检测到235个峰值区(126个为负峰值区),难以锁定核心候选区间,而30样本混池仅检测到21个峰值区,且主要集中于9号染色体;ED算法在50样本混池的99%置信水平下检测到22个峰值区(均位于9号染色体),30样本混池检测到13个峰值区(集中于9号染色体29.5 Mbp区间)。结合遗传连锁分析验证结果,SNP-index算法比ED算法更可靠。综上,辣椒果色基因BSA定位中,30株极端表型单株构建混池的效果优于50株,SNP-index算法更适合目标基因初定位,研究结果可为辣椒及同类作物BSA基因定位的实验设计提供参考。 展开更多
关键词 DNA混池 辣椒果色 集群分离分析 SNP-index算法 欧氏距离算法
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不同果袋对阳光玫瑰葡萄果实外观品质的影响
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作者 赵志强 边凤霞 +2 位作者 刘卫英 李斗 王富霞 《浙江农业科学》 2026年第4期949-952,共4页
本试验以六年生嫁接阳光玫瑰葡萄为材料,在幼果期进行套袋处理,探究4种不同果袋对果实外观品质的影响。结果表明,绿色果袋(M1)、三色果袋(M4)处理的果实单粒重分别比不套袋(CK)显著(p<0.05)提高6.4%、8.2%。新型半透明果袋(M3)、M4... 本试验以六年生嫁接阳光玫瑰葡萄为材料,在幼果期进行套袋处理,探究4种不同果袋对果实外观品质的影响。结果表明,绿色果袋(M1)、三色果袋(M4)处理的果实单粒重分别比不套袋(CK)显著(p<0.05)提高6.4%、8.2%。新型半透明果袋(M3)、M4处理的单穗重分别比CK显著提高了4.3%、7.4%,M4处理单穗重最高。套袋对果梗粗度没有显著影响。M4处理的果皮硬度显著高于CK。套袋显著提高了果实L^(∗)值、b^(∗)值,其中以M4处理效果最好。综上,三色果袋对提高阳光玫瑰葡萄外观品质有显著效果。 展开更多
关键词 阳光玫瑰葡萄 果实套袋 外观品质 色泽指数
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板栗壳提取液染色棉织物色度指标研究
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作者 劳洪烽 董福星 +1 位作者 赵连英 顾学锋 《棉纺织技术》 2026年第4期26-33,共8页
探究板栗壳提取液上染全棉汗布的色度指标。使用精练剂和双氧水练漂棉织物,以3-氯-2-羟丙基三甲基氯化铵(SH)作为改性剂,板栗壳提取液作为染色剂,FeSO4和柠檬酸作为媒染剂,分别改变改性剂SH质量浓度、NaOH质量浓度、板栗壳提取液质量分... 探究板栗壳提取液上染全棉汗布的色度指标。使用精练剂和双氧水练漂棉织物,以3-氯-2-羟丙基三甲基氯化铵(SH)作为改性剂,板栗壳提取液作为染色剂,FeSO4和柠檬酸作为媒染剂,分别改变改性剂SH质量浓度、NaOH质量浓度、板栗壳提取液质量分数、板栗壳提取液pH值和媒染剂质量浓度等因素,研究板栗壳提取液在各影响因素下媒染前后色度指标的变化。通过对织物色度指标L^(*)、a^(*)、b^(*)的测定,将数据导入Origin软件进行拟合并绘制拟合曲线。结果表明:在提取液质量分数为50%、pH值为3、改性剂SH质量浓度为30 g/L、NaOH质量浓度为8 g/L时,织物的颜色最深且黄光和红光最强;各影响因素与染色棉织物的色度指标之间呈较好的三次函数关系;媒染后棉织物色牢度有所提高,但随着板栗壳提取液质量分数的增加,湿摩擦色牢度和水洗摩擦色牢度有一定的降低,光照色牢度则会提高。认为:该研究结果可用于预测板栗壳提取液上染全棉汗布的色度指标以及颜色,帮助企业提高打样效率。 展开更多
关键词 板栗壳提取液 棉织物 色度指标 拟合方程 色牢度
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电子纸前导光板专用LED灯珠设计与增色优化研究
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作者 张海锋 朱剑飞 +2 位作者 黄柳静 李华尹 丁七七 《信息技术与标准化》 2026年第3期42-47,共6页
为了提升电子纸的显示效果,聚焦电子纸产品前导光板专用LED灯珠,系统阐述其分类体系,明确不同分类维度与电子纸产品的适配关系,深入剖析侧入式灯珠光型、结构、光电性能、驱动与排布等设计要点,详细梳理其光学性能参数及测试方法,重点... 为了提升电子纸的显示效果,聚焦电子纸产品前导光板专用LED灯珠,系统阐述其分类体系,明确不同分类维度与电子纸产品的适配关系,深入剖析侧入式灯珠光型、结构、光电性能、驱动与排布等设计要点,详细梳理其光学性能参数及测试方法,重点探讨不同技术方案对色域的影响,为解决电子纸产品在弱光环境下的使用体验问题提供理论与技术支撑。 展开更多
关键词 电子纸产品 前导光板 LED灯珠 侧入式LED 显色指数
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基于ZnO微球的光子晶体结构生色颜料制备及其在纤维材料上的应用
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作者 李晓雯 莫东海 +3 位作者 蒋亚群 柴丽琴 刘国金 周岚 《复合材料学报》 北大核心 2026年第1期246-254,共9页
针对微球分散液储存不稳定,易出现团聚、沉降等问题,提出以高折射率的氧化锌(ZnO)微球为主体制备以固体形式存在的光子晶体结构生色颜料,并利用丝网印花方式在柔性纤维材料上构筑图案化的光子晶体结构体。分析ZnO微球的粒径、单分散性... 针对微球分散液储存不稳定,易出现团聚、沉降等问题,提出以高折射率的氧化锌(ZnO)微球为主体制备以固体形式存在的光子晶体结构生色颜料,并利用丝网印花方式在柔性纤维材料上构筑图案化的光子晶体结构体。分析ZnO微球的粒径、单分散性、形貌等性能,设计结构色颜料体系,并对结构色颜料进行性能评价,考察纤维材料上丝网印花所得光子晶体结构体的结构色效果和结构稳定性。结果表明:以粒径均一、具有良好的球形度和优异单分散性的ZnO微球为主体,通过掺杂炭黑,可制备得到固态型结构生色颜料,分别使用268 nm、223 nm和157 nm的微球可依次得到红色、绿色和蓝色的结构色颜料。当加入炭黑用量为0.12%时,颜料的反射率峰值在30%左右,颜料颜色均匀,色彩效果最佳。以制备所得结构生色颜料为着色剂,通过丝网印花方式在涤纶纤维材料上构筑的光子晶体生色结构显色明亮,经过多次摩擦和折叠弯曲测试未出现脱落、结构色消减等现象,表现出优异的稳固性和耐久性。研究结果为光子晶体结构生色材料的制备提供了策略支撑。 展开更多
关键词 高折射率 氧化锌微球 光子晶体 结构生色颜料 丝网印花
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2013—2024年南海沿岸河口遥感水色时空变化特征
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作者 黄柳红 范晓梅 +1 位作者 詹鹏飞 宋春桥 《地球信息科学学报》 北大核心 2026年第3期691-705,共15页
【目的】河口作为陆海交互作用的关键区域,其水质变化直接影响沿岸生态系统服务功能和人类健康福祉。然而,受潮汐、径流、悬浮物和有色可溶性有机物等多重因素共同作用,河口水环境往往表现出高度复杂性与动态性,发展有效的水环境遥感监... 【目的】河口作为陆海交互作用的关键区域,其水质变化直接影响沿岸生态系统服务功能和人类健康福祉。然而,受潮汐、径流、悬浮物和有色可溶性有机物等多重因素共同作用,河口水环境往往表现出高度复杂性与动态性,发展有效的水环境遥感监测方法至关重要。FUI(Forel-Ule Index)水色指数通过21级色标(1-21)量化水体颜色,可有效表征水质特征。因此,本研究利用长时序卫星遥感数据,对南海沿岸河口开展大尺度FUI监测,以揭示河口水体颜色的空间分布格局与演变特征,探索FUI水色指数在复杂河口环境中的适用性与生态指示价值。【方法】本研究利用2013—2024年Landsat-8和Landsat-9卫星遥感影像,提取南海沿岸245个河口的FUI水色指数并分析空间分布特征,结合Theil-Sen Median趋势分析法和Mann-Kendall检验分析年际变化趋势,进一步对比干湿季的时空分布差异。【结果】(1)空间格局上,南海沿岸河口FUI多年均值范围为11~21,平均值为17.30。南海周边岸带(泰国湾最低,东部海岸最高)与国家间(柬埔寨最低,菲律宾最高)存在显著差异;(2)年际变化显示,近10年南海沿岸河口FUI年际变化趋势存在差异,中国、越南等国河口水色向绿色转变,而马来西亚、印度尼西亚等国河口水色趋向更浑浊的黄棕色;(3)干湿季河口FUI空间分布存在差异,在干季,中国广东省、泰国南部以及柬埔寨河口FUI较其他地区低,湿季FUI高值集中分布于越南北部至马来半岛西岸。年际变化上,干季年际变化率均值为-0.02/年,湿季河口FUI的年际变化率均值为-0.004/年,2013—2024年干湿季FUI整体波动幅度较小,湿季FUI始终高于干季且差异稳定。【结论】南海沿岸河口FUI的空间与时间变化特征揭示出水色存在显著的地域分异和季节特征,反映出区域人类活动、水文条件的综合影响。本研究不仅拓展了FUI水色指数在复杂河口环境中的适用性,也为南海沿岸河口水质的长期监测、生态环境评估与跨国水环境管理提供了关键的基础信息。 展开更多
关键词 河口 水质 Forel-Ule index 水体颜色 Landsat-8 Landsat-9 南海 遥感
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经颅彩色多普勒超声监测参数变化对高血压脑出血术后患者预后的影响因素分析
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作者 廖柱山 杨岸琼 +1 位作者 钟冬华 韦荣川 《影像研究与医学应用》 2026年第3期38-40,44,共4页
目的:分析经颅彩色多普勒超声(TCCD)监测参数变化对高血压脑出血(HICH)术后患者预后的影响因素。方法:选取2023年1月—2025年6月在贵港市覃塘区人民医院治疗的120例HICH术后患者为研究对象。按照患者术后预后情况分为预后良好组(n=67)... 目的:分析经颅彩色多普勒超声(TCCD)监测参数变化对高血压脑出血(HICH)术后患者预后的影响因素。方法:选取2023年1月—2025年6月在贵港市覃塘区人民医院治疗的120例HICH术后患者为研究对象。按照患者术后预后情况分为预后良好组(n=67)和预后不良组(n=53)。采用多因素Logistic回归,分析TCCD监测参数对HICH术后患者预后的独立影响因素。结果:与预后良好组相比,预后不良组术后1、3、7 d患侧舒张期血流速度(EDV)均更低,搏动指数(PI)、阻力指数(RI)均更高(P<0.05);预后不良组术后3、7d患侧平均血流速度(TAMV)更低(P<0.05);预后不良组术后7d患侧收缩期峰值血流速度(PSV)更高(P<0.05)。多因素Logistic回归分析显示,术后1、3、7d的视神经鞘直径(ONSD)、PI均是HICH术后患者预后的独立影响因素(P<0.05)。结论:HICH术后预后不良与以高阻力、低灌注为特征的脑血流动力学变化密切相关;且术后PI的进行性升高,是患者预后不良的独立危险因素。 展开更多
关键词 经颅多普勒超声 高血压脑出血 搏动指数 阻力指数 脑血流动力学
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Color-converted remote phosphor prototype of a multiwavelength excitable borosilicate glass for white light-emitting diodes
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作者 田华 刘技文 +2 位作者 仇坤 宋俊 王达健 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期579-582,共4页
We report a unique red light-emitting Eu-doped borosilicate glass to convert color for warm white light-emitting diodes. This glass can be excited from 394 nm-peaked near ultraviolet light, 466 nm-peaked blue light, t... We report a unique red light-emitting Eu-doped borosilicate glass to convert color for warm white light-emitting diodes. This glass can be excited from 394 nm-peaked near ultraviolet light, 466 nm-peaked blue light, to 534 nm- peaked green light to emit the desired red light with an excellent transmission in the wavelength range of 400-700 nm which makes this glass suitable for color conversion without a great cost of luminous power loss. In particular, when assembling this glass for commercial white light-emitting diodes, the tested results show that the color rendering index is improved to 84 with a loss of luminous power by 12 percent at average, making this variety of glass promising for inorganic "remote-phosphor" color conversion. 展开更多
关键词 white light-emitting diodes (WLEDs) color rendering index remote phosphor borosil-icate glass
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Correlation Study of Color Doppler Examination of Deep Veins of Both Lower Extremities Combined with Fibrinolysis System in Hypertension during Pregnancy 被引量:4
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作者 Chundong Qiu Haiyan Chen +3 位作者 Xiaohua Huang Xiaoling Kong Chong Liang Chunhong Qiu 《Open Journal of Obstetrics and Gynecology》 2020年第8期981-989,共9页
<strong>Objective</strong><span style="font-family:Verdana;"><strong>:</strong></span><span style="font-family:Verdana;"> To investigate the correlation be... <strong>Objective</strong><span style="font-family:Verdana;"><strong>:</strong></span><span style="font-family:Verdana;"> To investigate the correlation between deep static color Doppler ultrasound of both lower extremities combined with fibrinolytic system detection in pregnancy-induced hypertension.</span><span style="font-family:""> </span><b><span style="font-family:Verdana;">Methods</span></b><b><span style="font-family:Verdana;">:</span></b><span style="font-family:Verdana;"> A total of 70 normal pregnant women, 70 pregnant women with hypertension during pregnancy, and 50 healthy non-pregnant women in the same period were selected as the research objects. The deep veins of both lower limbs were examined by Rili Erlangshen’s color Doppler ultrasound diagnostic instrument (CDU),</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">and the </span><span style="font-family:Verdana;">fibrinolysis system was tested by enzyme-linked immunosorbent assay (ELISA) </span><span style="font-family:Verdana;">method and </span><a name="OLE_LINK12"></a><span style="font-family:Verdana;">automatic hemagglutination analyzer.</span><b><span style="font-family:Verdana;"> Results</span></b></span><b><span style="font-family:Verdana;">:</span></b><b><span style="font-family:""> </span></b><span style="font-family:Verdana;">Compared with the non-pregnant group, the inner diameters of the left/right femoral vein (CFV) and popliteal vein (POV) in the normal pregnancy group and the pregnancy-induced hypertension group were significantly widened, and the peak blood flow spectrum was significantly reduced. The difference was statistically significant (P < 0.01);FIB, PLG, t-PA, PAI, D-Dimer were significantly increased, the difference was statistically significant (P < 0.01);Compared with the normal pregnancy group, the inner diameter of the left/right femoral vein (CFV) in the hypertensive pregnancy group was significantly wider than that in the normal pregnancy group, and the peak value of the left/right POV blood flow spectrum was significantly lower than that in the normal pregnancy group,</span><span style="font-family:""> </span><span style="font-family:Verdana;">the difference w</span><span style="font-family:Verdana;">as</span><span style="font-family:Verdana;"> statistically significant (P < 0.01)</span><span style="font-family:Verdana;">,</span><span style="font-family:""> <span style="font-family:Verdana;">while the left/right popliteal vein (POV) inner diameter, left/right CFV blood flow peak value did not change significantly from the normal pregnancy</span><span style="font-family:Verdana;"> grou</span></span><span style="font-family:Verdana;">p, </span><span style="font-family:Verdana;">and the difference was not statistically significant (P > 0.05);FIB, PLG, PAI, D-Dimer of the hypertensive disease group during pregnancy significantly increased, the difference was statistically significant (P < 0.01), while t-PA was not statistically significant (P > 0.05).</span><span style="font-family:""> </span><b><span style="font-family:Verdana;">Conclusion</span></b><b><span style="font-family:Verdana;">:</span></b><b><span style="font-family:""> </span></b><span style="font-family:Verdana;">Normal pregnant women have a hypercoagulable state compared with healthy non-pregnant women, and pregnant women with hypertension during pregnancy are more likely to be in a pre-thrombotic state than pregnant women with normal pregnancy. Deep vein CDU examination of both lower extremities combined with blood fibrinolysis monitoring is of great value in the prevention and treatment of hypertension during pregnancy.</span> 展开更多
关键词 Hypertension during Pregnancy Prothrombotic State color Doppler Ultrasound Fibrinolysis index
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