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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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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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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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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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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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A New Fire Detection Method Using a Multi-Expert System Based on Color Dispersion, Similarity and Centroid Motion in Indoor Environment 被引量:10
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作者 Teng Wang Leping Bu +2 位作者 Zhikai Yang Peng Yuan Jineng Ouyang 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2020年第1期263-275,共13页
In this paper, a video fire detection method is proposed, which demonstrated good performance in indoor environment. Three main novel ideas have been introduced. Firstly, a flame color model in RGB and HIS color space... In this paper, a video fire detection method is proposed, which demonstrated good performance in indoor environment. Three main novel ideas have been introduced. Firstly, a flame color model in RGB and HIS color space is used to extract pre-detected regions instead of traditional motion differential method, as it’s more suitable for fire detection in indoor environment. Secondly, according to the flicker characteristic of the flame, similarity and two main values of centroid motion are proposed. At the same time, a simple but effective method for tracking the same regions in consecutive frames is established. Thirdly,a multi-expert system consisting of color component dispersion,similarity and centroid motion is established to identify flames.The proposed method has been tested on a very large dataset of fire videos acquired both in real indoor environment tests and from the Internet. The experimental results show that the proposed approach achieved a balance between the false positive rate and the false negative rate, and demonstrated a better performance in terms of overall accuracy and F standard with respect to other similar fire detection methods in indoor environment. 展开更多
关键词 color dispersion centroid motion expert system RGB-HIS color model SIMILARITY video fire detection
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The Study of Ovarian Artery Hemodynamics in Patients with Infertility by Color Doppler Energy 被引量:2
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作者 肖先桃 乐桂蓉 +1 位作者 张友耿 黎春蕾 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2001年第1期42-43,共2页
Seventy four cases of infertility were examined to study the hemodynamics of the bilateral ovarian arteries at 21st day during the corpus luteum phase by color Doppler energy(CDE) and color Doppler flow imaging (CDFI... Seventy four cases of infertility were examined to study the hemodynamics of the bilateral ovarian arteries at 21st day during the corpus luteum phase by color Doppler energy(CDE) and color Doppler flow imaging (CDFI). All the patients were verified by laparoscopy, fallopian tube patency examination and ovarian function test. Twenty two healthy women served as controls. The results showed that the difference of resistance index(RI)and pulsatility index (PI) of bilateral ovarian arteries between the infertility and the normal controls had statistical significance ( P <0.01), and the PI showed negative correlation with the thickness of endometrium (left side: r =0.724, P <0.01; right side: r =0.756, P <0.01). The results also showed that CDE was more sensitive than CDFI in displaying the ovarian arteries. It could be concluded that the elevated resistance of ovarian artery during the corpus luteum phase was one of the important factors that resulted in infertility. 展开更多
关键词 ovarian artery color Doppler flow imaging color Doppler energy resistance index pulsatility index INFERTILITY
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基于Landsat影像的长寿湖水体营养状态时空变化遥感研究 被引量:1
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作者 张辰 夏婧 +2 位作者 闵天 梁思 田婧怡 《华中师范大学学报(自然科学版)》 北大核心 2025年第1期135-144,共10页
湖泊的营养状态和变化趋势研究对科学认知湖泊水质演变规律和治理湖泊生态环境具有重要意义.水体颜色指数(FUI)与湖泊的营养程度密切相关,是评估湖泊营养状态及其变化规律的有效指标.本研究以重庆市长寿湖为研究区,利用1986-2022年间的L... 湖泊的营养状态和变化趋势研究对科学认知湖泊水质演变规律和治理湖泊生态环境具有重要意义.水体颜色指数(FUI)与湖泊的营养程度密切相关,是评估湖泊营养状态及其变化规律的有效指标.本研究以重庆市长寿湖为研究区,利用1986-2022年间的Landsat5/7/8系列遥感数据,计算水体的FUI指数,由此评价水体营养状态,并结合变异系数、Sen斜率及Mann-Kendall(M-K)参数检验变化趋势分析法,探讨长寿湖及其不同功能分区近40年间水体营养状态的时空变化.结果表明:1)长寿湖水体多年来主要处于中营养状态,2002年后水质持续稳定好转;富营养水域主要集中于西部生态养殖区;2)西部生态养殖区FUI值变异系数最大(0.17),自2002年后营养状态趋于稳定改善,水质明显好转的区域多分布于湖区的中部和西北部;3)中部生态旅游区FUI值变异系数最低(0.10),营养状态多年较为稳定,水质好转和恶化的区域共存,其湖区中西部FUI值呈显著下降趋势,富营养化等级明显降低;4)东部湿地保护区的营养状态以中营养向富营养转变为主,水体富营养化风险加剧.研究结果为长寿湖水环境监测与评价提供了重要参考. 展开更多
关键词 水体颜色指数 富营养化 遥感提取 Landsat影像 长寿湖
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发光塑料光谱调控的计算机模拟与分析 被引量:1
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作者 邢晓莉 王德涛 《合成树脂及塑料》 北大核心 2025年第1期64-68,共5页
以青粉用量和半波宽为变量,光通量、显色指数、色温等光色参数为评价指标,采用计算机模拟技术对青粉调控的发光塑料光谱进行了研究。结果表明:随着青粉用量的增加,光通量降低,最高降幅达54%,显色指数则先升高后降低,在青粉用量为7%(w)... 以青粉用量和半波宽为变量,光通量、显色指数、色温等光色参数为评价指标,采用计算机模拟技术对青粉调控的发光塑料光谱进行了研究。结果表明:随着青粉用量的增加,光通量降低,最高降幅达54%,显色指数则先升高后降低,在青粉用量为7%(w)时具有最优值(94.33);未掺杂青粉时,蓝光强度非常大,色温为8913 K,青粉用量为11%(w)时,色温为3571 K,色坐标则表现出线性关系;光通量随着半波宽的变化幅度较小,半波宽为5.0 nm时,光通量为33.58 lm,半波宽增加到15.0 nm时,光通量为34.15 lm,增幅仅为2%,色温变化最大值仅为247 K,显色指数在半波宽12.5 nm时具有最优值(94.33);青粉用量为7%(w),半波宽为12.5 nm时,显色指数为94.33,色温为4078K,色坐标为(0.3865,0.3839)。 展开更多
关键词 发光塑料 计算机模拟 光谱调控 光通量 显色指数 色温
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Equitable Strong Edge Coloring of the Joins of Paths and Cycles 被引量:2
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作者 Tao WANG Ming Ju LIU De Ming LI 《Journal of Mathematical Research with Applications》 CSCD 2012年第1期11-18,共8页
For a proper edge coloring c of a graph G, if the sets of colors of adjacent vertices are distinct, the edge coloring c is called an adjacent strong edge coloring of G. Let ci be the number of edges colored by i. If [... For a proper edge coloring c of a graph G, if the sets of colors of adjacent vertices are distinct, the edge coloring c is called an adjacent strong edge coloring of G. Let ci be the number of edges colored by i. If [ci - cj] ≤1 for any two colors i and j, then c is an equitable edge coloring of G. The coloring c is an equitable adjacent strong edge coloring of G if it is both adjacent strong edge coloring and equitable edge coloring. The least number of colors of such a coloring c is called the equitable adjacent strong chromatic index of G. In this paper, we determine the equitable adjacent strong chromatic index of the joins of paths and cycles. Precisely, we show that the equitable adjacent strong chromatic index of the joins of paths and cycles is equal to the maximum degree plus one or two. 展开更多
关键词 adjacent strong edge coloring equitable edge coloring joins of paths cycle maximum degree chromatic index.
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山东烟区上部叶不同田间成熟度对颜色指标及烤烟品质的影响
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作者 张杨 杜玉海 +4 位作者 董小卫 刘洋 刘力玮 闫慧峰 孔德才 《安徽农业科学》 2025年第9期158-161,共4页
为明确不同成熟度科学表征方法和不同成熟度对烤烟品质的影响,将上六片叶片的田间成熟度分为尚熟、成熟、完熟3个处理,对相应叶位叶片厚度及烤后烟叶的化学成分和感官质量进行分析,并比较不同成熟度叶片的不同类型颜色指标的差异。结果... 为明确不同成熟度科学表征方法和不同成熟度对烤烟品质的影响,将上六片叶片的田间成熟度分为尚熟、成熟、完熟3个处理,对相应叶位叶片厚度及烤后烟叶的化学成分和感官质量进行分析,并比较不同成熟度叶片的不同类型颜色指标的差异。结果表明:不同成熟度叶片厚度存在差异,上二叶位、上四叶位均为成熟处理最高,完熟处理最低,其中上二叶位成熟处理与完熟处理存在显著差异。随着采收成熟度的提高,上部烟叶香气质和香气量增加;浓度、香气质、香气量、余味、杂气表现为成熟处理最高。不同成熟度上部叶除少数颜色指标无显著差异,其余颜色指标均呈显著差异,颜色指标NRI、(R-B)/G、(R-B)/(R+G+B)、NGI、G/R、G/(R+B)、(G-B)/R、(G-B)/(R+G+B)可以很好地区分第二叶位叶片成熟度情况。 展开更多
关键词 上部叶 成熟度 烟叶质量 颜色指标 山东烟区
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波长连续型功能树脂的计算机仿真研究
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作者 牛聪 史海威 《合成树脂及塑料》 北大核心 2025年第1期51-54,86,共5页
基于计算机仿真的方法,研究了采用不同波长及用量荧光粉所制波长连续型功能树脂光色参数的变化规律。结果表明:波长为660 nm时,随着荧光粉含量的增加,光通量降低,显色指数先升后降,且在荧光粉质量分数6%时最大,为95.98;色温则由于光谱... 基于计算机仿真的方法,研究了采用不同波长及用量荧光粉所制波长连续型功能树脂光色参数的变化规律。结果表明:波长为660 nm时,随着荧光粉含量的增加,光通量降低,显色指数先升后降,且在荧光粉质量分数6%时最大,为95.98;色温则由于光谱中红光占比的增加而表现为降低趋势,从未掺杂荧光粉时的10587 K降至荧光粉质量分数10%时的2228 K;在荧光粉质量分数6%时,随着波长从620 nm增至660 nm,光通量降低,而显色指数则由于光谱拓宽效应表现为升高趋势,从80.81增至95.98;最优波长为660 nm,荧光粉质量分数为6%时,对应光通量为123lm,显色指数为95.98,色温为3320K。 展开更多
关键词 功能树脂 波长连续型 光通量 显色指数 色温
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