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Cryptochromes mRNA Expression Under Mating and Black light Treatment on Helicoverpa armigera
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作者 倪慧 闫硕 +1 位作者 刘小侠 张青文 《Plant Diseases and Pests》 CAS 2011年第3期20-23,30,共5页
[ Objective ] The paper was to confirm the effect of mating and black light treatment on cryptochromes mRNA expression of Hclicoverpa armigera. [ Method ] Quantitative real-time PCR ( SYBR Green) technique was appli... [ Objective ] The paper was to confirm the effect of mating and black light treatment on cryptochromes mRNA expression of Hclicoverpa armigera. [ Method ] Quantitative real-time PCR ( SYBR Green) technique was applied to detect the expression of cryptochromes gene ( cryl and cry2 ) of H. armigera under different conditions. Total RNA was extracted from the head of H. armigera, and carried out reverse transcription to synthesize cDNA after digested by DNase I. Specific primers were used to carry out quantitative real-time PCR on cryl, cry2 and EF-Ict gene, respectively. [ Result] The expression of cryl mRNA of H. ar- migera significantly decreased after exposure to black light for 2 h, the mRNA expression of cry2 was smaller than control, they had no significant difference with each other. Mating had significant effect on mRNA expression of cryl and cry2 of H. armigera, and the mRNA expression of cryl and cry2 of male and female adults showed decreasing trend with the prolongation of time after mating. [ Conclusion] The result had important significance for further studying on function of cry gene and the control of cotton bollwonn. 展开更多
关键词 Helicoverpa armigera cryl and cry2 Quantitative real-time PCR black light MATING China
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Black Photoresist for Patterning Pixel Define Layer of Organic Light Emitting Diode with Polyimide as Thermal Stabilizer 被引量:2
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作者 Genggongwo Shi Jin Woo Park Lee Soon Park 《Materials Sciences and Applications》 2018年第6期554-564,共11页
In order to improve the visibility for outside use of organic light emitting diodes (OLEDs), the polarized film and black matrix pattern have been used in the small and medium sized OLEDs;however, these cause problem ... In order to improve the visibility for outside use of organic light emitting diodes (OLEDs), the polarized film and black matrix pattern have been used in the small and medium sized OLEDs;however, these cause problem of reducing the emission efficiency of OLED. Changing the color of pixel define layer (PDL) from brown to black is an important point for improving the efficiency and visibility of OLEDs. In this work we studied the photoresist material containing black pigment and the photolithographic process for patterning of black PDL on OLEDs. The black PDL patterns made with our synthesized polyimides as thermal stabilizer were found to give high thermal stability over 300&deg;C. 展开更多
关键词 Organic light Emitting Diode PIXEL Define LAYER black PIXEL Define LAYER PHOTOLITHOGRAPHY
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Light-absorbing impurities on Keqikaer Glacier in western Tien Shan: concentrations and potential impact on albedo reduction 被引量:4
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作者 YuLan Zhang ShiChang Kang +11 位作者 Min Xu Michael Sprenger TanGuang Gao ZhiYuan Cong ChaoLiu Li JunMing Guo ZhiQiang Xu Yang Li Gang Li XiaoFei Li YaJun Liu HaiDong Han 《Research in Cold and Arid Regions》 CSCD 2017年第2期97-111,共15页
Light-absorbing impurities on glaciers are important factors that influence glacial surface albedo and accelerate glacier melt. In this study, the quantity of light-absorbing impurities on Keqikaer Glacier in western ... Light-absorbing impurities on glaciers are important factors that influence glacial surface albedo and accelerate glacier melt. In this study, the quantity of light-absorbing impurities on Keqikaer Glacier in western Tien Shan, Central Asia, was measured. We found that the average concentrations of black carbon was 2,180 ng/g, with a range from 250 ng/g to more than 10,000 ng/g. The average concentrations of organic carbon and mineral dust were 1,738 ng/g and 194 μg/g, respectively. Based on simulations performed with the Snow Ice Aerosol Radiative model simulations, black carbon and dust are responsible for approximately 64% and 9%, respectively, of the albedo reduction, and are associated with instantaneous radiative forcing of 323.18 W/m2(ranging from 142.16 to 619.25 W/m2) and 24.05 W/m2(ranging from 0.15 to69.77 W/m2), respectively. For different scenarios, the albedo and radiative forcing effect of black carbon is considerably greater than that of dust. The estimated radiative forcing at Keqikaer Glacier is higher than most similar values estimated by previous studies on the Tibetan Plateau, perhaps as a result of black carbon enrichment by melt scavenging. Light-absorbing impurities deposited on Keqikaer Glacier appear to mainly originate from central Asia, Siberia, western China(including the Taklimakan Desert) and parts of South Asia in summer, and from the Middle East and Central Asia in winter.A footprint analysis indicates that a large fraction(>60%) of the black carbon contributions on Keqikaer Glacier comes from anthropogenic sources. These results provide a scientific basis for regional mitigation efforts to reduce black carbon. 展开更多
关键词 light-absorbing IMPURITIES black carbon mineral dust GLACIER SNOW ALBEDO Tien Shan
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Aerosol light absorption in a coastal city in Southeast China:Temporal variations and implications for brown carbon 被引量:6
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作者 Yuqing Qiu Xin Wu +5 位作者 Yanru Zhang Lingling Xu Youwei Hong Jinsheng Chen Xiaoqiu Chen Junjun Deng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第6期257-266,共10页
Light-absorbing carbonaceous aerosols including black carbon(BC) and brown carbon(BrC)play significant roles in atmospheric radiative properties. One-year measurements of aerosol light absorption at multi-wavelength w... Light-absorbing carbonaceous aerosols including black carbon(BC) and brown carbon(BrC)play significant roles in atmospheric radiative properties. One-year measurements of aerosol light absorption at multi-wavelength were continuously conducted in Xiamen,southeast of China in 2014 to determine the light absorption properties including absorption coefficients(σabs) and absorption ?ngstr?m exponent(AAE) in the coastal city.Light absorptions of BC and BrC with their contributions to total light absorption were further quantified. Mean σabsat 370 nm and 880 nm were 56.6 ± 34.3 and 16.5 ± 11.2 Mm-1,respectively. σabspresented a double-peaks diurnal pattern with the maximum in the morning and the minimum in the afternoon. σabswas low in warm seasons and high in cold seasons. AAE ranged from 0.26 to 2.58 with the annual mean of 1.46, implying that both fossil fuel combustion and biomass burning influenced aerosol optical properties. σabsof BrC at 370 nm was 24.0 ± 5.7 Mm-1, contributing 42% to the total absorption. The highest AAE(1.52 ± 0.02) and largest BrC contributions(47% ± 4%) in winter suggested the significant influence of biomass burning on aerosol light absorption. Long-distance air masses passing through North China Plain and the Yangtze River Delta led to high AAE and BrC contributions. High AAE value of 1.46 in July indicated that long-range transport of the air pollutants from intense biomass burning in Southeast Asia would affect aerosol light absorption in Southeast China. The study will improve the understanding of light absorption properties of aerosols and the optical impacts of BrC in China. 展开更多
关键词 light ABSORPTION BROWN CARBON black CARBON ABSORPTION ANGSTROM exponent Biomass burning Western Taiwan STRAIT
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高空灯与黑光灯对草地螟成虫监测效果的差异分析 被引量:2
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作者 程云霞 康爱国 +2 位作者 王泱洋 高峰 江幸福 《植物保护》 北大核心 2025年第3期62-68,共7页
随着高空灯在草地螟Loxostege sticticalis种群动态监测中的普遍应用,分析高空灯的监测数据特点及其与传统黑光灯差异,对基于高空灯监测数据进行种群动态趋势预测有着重要的意义。本研究通过提取并定义一系列的描述参数,系统分析了河北... 随着高空灯在草地螟Loxostege sticticalis种群动态监测中的普遍应用,分析高空灯的监测数据特点及其与传统黑光灯差异,对基于高空灯监测数据进行种群动态趋势预测有着重要的意义。本研究通过提取并定义一系列的描述参数,系统分析了河北省康保县2014年-2023年连续10年高空灯及黑光灯监测草地螟成虫的动态数据,比较了高空灯与传统黑光灯对草地螟成虫监测的差异及相同点。结果表明,高空灯监测下全年累计草地螟成虫诱集量是黑光灯的10倍以上;高空灯下雌蛾占比为0.53,显著低于黑光灯;高空灯下始见期和终见期分别平均早于黑光灯3 d和2 d。在同一个蛾峰期内,高空灯监测到的高峰日期比黑光灯平均早1 d。高空灯和黑光灯对草地螟监测的一致之处体现在:2种监测设备所示虫量的相对多少的年度变化趋势相同,且整个监测期蛾峰次数均为3~4次,蛾峰持续天数均为1~2 d。造成高空灯和黑光灯监测数据差异的主要原因是:两者分别对高空过境虫源和近地面虫源具有诱集优势。分析结果对于高空灯在草地螟种群预测预报上的应用提供了依据。 展开更多
关键词 草地螟 高空灯 黑光灯 监测 始见期 终见期 蛾峰
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Higher-Order Corrections for the Deflection of Light around a Massive Object. Diagonal PadéApproximants and Ray-Tracing Algorithms
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作者 Carlos Rodriguez Carlos Marín 《International Journal of Astronomy and Astrophysics》 2018年第1期121-141,共21页
From the Schwarzschild metric we obtain the higher-order terms for the deflection of light around a massive object using the Lindstedt-Poincaré method to solve the equation of motion of a photon around the stella... From the Schwarzschild metric we obtain the higher-order terms for the deflection of light around a massive object using the Lindstedt-Poincaré method to solve the equation of motion of a photon around the stellar object. The asymptotic series obtained by this method was obtained up to order 20 in the expansion parameter, and was found to better approximate the numerical solution with higher order terms—a property that can’t be taken for granted for any asymptotic series. Additionally, we obtain diagonal Padé approximants from the perturbation expansion, and we show how these are a better fit for the numerical data than the original formal Taylor series. Furthermore, we use these approximants in ray-tracing algorithms to model the bending of light around massive objects. 展开更多
关键词 light DEFLECTION black Hole Padé
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Non-Local Theory of Bose-Einstein Condensate and Stopping of Light
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作者 Boris V. Alexeev 《Journal of Applied Mathematics and Physics》 2022年第7期2200-2215,共16页
The problem of an adequate description of the transport processes in Bose-Einstein condensates (CBE), including space-temporal evolution of CBE in a gravitational field is considered. The full nonlocal system for the ... The problem of an adequate description of the transport processes in Bose-Einstein condensates (CBE), including space-temporal evolution of CBE in a gravitational field is considered. The full nonlocal system for the CBE evolution is delivered including particular case and analytical solutions. We show (analytically) that a black hole can evolve in the Bose-Einstein condensate (CBE) regime. At the same time, there are modes in which black hole flickering occurs. Quantization of the black holes flickering is discovered. The corresponding nonlocal hydrodynamic equations indicated for fermions gas. 展开更多
关键词 Nonlocal Physics Transport Processes in Bose-Einstein Condensate black Hole Flickering light Stopping Nonlocal Hydrodynamic Equations for Fermions Gas
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Black Holes and the Nature of the Expansion of the Universe
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作者 Paul Smeulders 《Journal of Modern Physics》 2016年第9期908-910,共3页
Black Holes absorb matter and because matter has structure in space and time, Black Holes absorb the grid points of space and time. It is this property that creates a void for the remaining visible space-time to expan... Black Holes absorb matter and because matter has structure in space and time, Black Holes absorb the grid points of space and time. It is this property that creates a void for the remaining visible space-time to expand into. This expansion is roughly proportional to the density of the black holes in space and this, because also time is expanding, leads to an apparent exponential expansion for the observer, who is unaware of this. Further the Quantum Mechanical effects: the Heisenberg uncertainty principle and the Tunnelling of particles lead to a flow of matter from the present time into the past. The red-shift is thus not just a sign of an expanding universe but also (and perhaps all of it) that of matter hurling down into the black holes. 展开更多
关键词 Expansion of Universe black Holes Speed of light Big Bang
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Light treatment for seasonal Winter depression in African-American vs Caucasian outpatients
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作者 Hyacinth N Uzoma Gloria M Reeves +12 位作者 Patricia Langenberg Baharak Khabazghazvini Theodora G Balis Mary A Johnson Aamar Sleemi Debra A Scrandis Sarah A Zimmerman Dipika Vaswani Gagan Virk Nijjar Johanna Cabassa Manana Lapidus Kelly J Rohan Teodor T Postolache 《World Journal of Psychiatry》 SCIE 2015年第1期138-146,共9页
AIM: To compare adherence, response, and remission with light treatment in African-American and Caucasian patients with Seasonal Affective Disorder.METHODS: Seventy-eight study participants, agerange 18-64(51 African-... AIM: To compare adherence, response, and remission with light treatment in African-American and Caucasian patients with Seasonal Affective Disorder.METHODS: Seventy-eight study participants, agerange 18-64(51 African-Americans and 27 Caucasians)recruited from the Greater Baltimore Metropolitan area, with diagnoses of recurrent mood disorder with seasonal pattern, and confirmed by a Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders-Ⅳ, were enrolled in an open label study of daily bright light treatment. The trial lasted6 wk with flexible dosing of light starting with 10000 lux bright light for 60 min daily in the morning. At the end of six weeks there were 65 completers. Three patients had Bipolar Ⅱ disorder and the remainder had Major depressive disorder. Outcome measures were remission(score ≤ 8) and response(50% reduction)in symptoms on the Structured Interview Guide for the Hamilton Rating Scale for Depression(SIGH-SAD)as well as symptomatic improvement on SIGH-SAD and Beck Depression Inventory-Ⅱ. Adherence was measured using participant daily log. Participant groups were compared using t-tests, chi square, linear and logistic regressions. RESULTS: The study did not find any significant group difference between African-Americans and their Caucasian counterparts in adherence with light treatment as well as in symptomatic improvement.While symptomatic improvement and rate of treatment response were not different between the two groups,African-Americans, after adjustment for age, gender and adherence, achieved a significantly lower remission rate(African-Americans 46.3%; Caucasians 75%; P =0.02).CONCLUSION: This is the first study of light treatment in African-Americans, continuing our previous work reporting a similar frequency but a lower awareness of SAD and its treatment in African-Americans. Similar rates of adherence, symptomatic improvement and treatment response suggest that light treatment is a feasible, acceptable, and beneficial treatment for SAD in African-American patients. These results should lead to intensifying education initiatives to increase awareness of SAD and its treatment in African-American communities to increased SAD treatment engagement.In African-American vs Caucasian SAD patients a remission gap was identified, as reported before with antidepressant medications for non-seasonal depression, demanding sustained efforts to investigate and then address its causes. 展开更多
关键词 SEASONAL affective disorder Depression light treatment AFRICAN-AMERICAN black REMISSION gap ETHNICITY Race
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Black Hole Singularities and Planetary Formation
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作者 Louise Riofrio 《Journal of Applied Mathematics and Physics》 2024年第4期1079-1088,共10页
The goal of this research is to explore the effects of black hole singularities. Methodology is to start with large objects like galaxies and continue to smaller objects within our solar neighbourhood. High-redshift o... The goal of this research is to explore the effects of black hole singularities. Methodology is to start with large objects like galaxies and continue to smaller objects within our solar neighbourhood. High-redshift observations from the James Webb Space Telescope reveal that distant galaxies and their central black holes formed shortly after the Big Bang. An innovation about the speed of light explains how supermassive black holes could have formed primordially. Predictions of Hawking radiation include the possibility of black holes contributing to the energy of stars such as the Sun. Black holes have also been suggested as a source of radiation and magnetic fields in giant planets. Observations of Enceladus raise the possibility that this moon and other objects near Saturn’s Rings contain small singularities. Extrapolations of this methodology indicate that black holes could exist within solar system bodies including planets. Extended discussion describes how their presence could explain mysteries of internal heat, planetary magnetic fields, and processes of solar system formation. 展开更多
关键词 black Holes GALAXIES Magnetic Fields Planets Planetary Formation Speed of light
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The Relativity of Cosmic Time: The Universe Is a Black Hole
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作者 Pascal Churoux 《Journal of Modern Physics》 2015年第13期1840-1851,共12页
Up to now, cosmology metrics have been based on Einstein relativity, established in 1905. Hubble has discovered the correlation between redshift and distance. Cosmology interprets the redshift as an expansion effect a... Up to now, cosmology metrics have been based on Einstein relativity, established in 1905. Hubble has discovered the correlation between redshift and distance. Cosmology interprets the redshift as an expansion effect a(t) through the ΛCDM model. We have proposed a new theory to explain Hubble law. The theory has been validated against observation data. It proposes a new approach of time which introduces the cosmic time tc. Cosmic time is an absolute reference to universe. It is zero at the edge with tc = 0, tc = T at the observer position and tc = s for any source between the edge and the observer, with T > s > 0. This theory acts like the relativity of space-time. The redshift is interpreted as a perspective parameter p(tc) = tc/T. Using gravitation, it is the Einstein effect applied to the uni-verse. This paper comments and interprets further consequences of this new theory. We emphasize the difference between duration (as usually used in classical cosmologic metrics) and the cosmic time tc as a notion of date. It induces two related effects: relativity of speed of light and time stretching. We explain why the cosmological standard model is not well suited to describe the Hubble law, to describe the universe. We also explain why gravitation and temperature increase when going from the center to the edge of the universe, when going from present to birth. The model has no use of black energy. As a consequence, the universe is seen as a black hole created by the cosmic time shock wave when tc = 0. 展开更多
关键词 HUBBLE Law Space-Time RELATIVITY light Speed UNIVERSE Expansion REDSHIFT Big Bang black Hole COSMIC TIME
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光质处理对黑色稻光合特性及其产量的影响
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作者 邹杭宇 陈蒙 +2 位作者 代雅萱 史宇航 刘海峰 《东北农业大学学报》 北大核心 2025年第4期1-12,共12页
以黑色稻种质资源——“延黑205”为试验材料,设置不同光质补光处理[蓝光(B)、红光(R)、紫光(P)],测定黑色稻生长指标、光合性能、次生代谢物质及抗氧化酶活性变化,探究各生理指标间变化规律及相关性,解析光质对黑色稻光合特性和产量的... 以黑色稻种质资源——“延黑205”为试验材料,设置不同光质补光处理[蓝光(B)、红光(R)、紫光(P)],测定黑色稻生长指标、光合性能、次生代谢物质及抗氧化酶活性变化,探究各生理指标间变化规律及相关性,解析光质对黑色稻光合特性和产量的影响。结果表明:蓝光处理下,黑色稻表现出良好的生长性状,显著提升叶片光合色素质量分数、Rubisco羧化酶活性和光合效率,且激活其抗氧化酶系统,减少叶片中丙二醛积累,保持细胞膜稳定,次生代谢物质质量分数积累最高,产量较高;红光处理下,黑色稻的穗数和每穗粒数增加,但该处理下,光合作用和抗氧化能力弱于蓝光处理;紫光处理下,在补光处理前期改善光合作用和抗氧化能力,但随着光处理时间增加,产生胁迫效应,导致活性氧积累,抑制产量提高。综上,黑色稻在蓝光处理下效果最好,可有效提升黑色稻光合特性、色素质量分数、抗氧化能力及产量。 展开更多
关键词 黑色稻 光质处理 光响应 光合特性 产量
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电场驱动少层黑磷激子近红外发光器件
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作者 梁雅宁 张君蓉 +5 位作者 王思源 王相懿 姚允 邢娟娟 王俊勇 张凯 《发光学报》 北大核心 2025年第9期1694-1702,共9页
二维半导体具有原子层极限厚度和范德华集成特性,发光在室温下由激子主导,是微纳光电子器件的前沿研究材料。其中,电激发的激子发光器件是研究其新奇发光物理和推进微纳光电器件集成应用的关键。当前,二维半导体激子发光器件主要集中于... 二维半导体具有原子层极限厚度和范德华集成特性,发光在室温下由激子主导,是微纳光电子器件的前沿研究材料。其中,电激发的激子发光器件是研究其新奇发光物理和推进微纳光电器件集成应用的关键。当前,二维半导体激子发光器件主要集中于可见光波段,近红外通讯波段电致发光器件的构筑还存在挑战。本研究基于双层和三层黑磷的激子近红外荧光特性,利用横向电场对其激子发光进行调控,并进一步构筑了电场驱动的非注入型激子近红外发光器件,工作波长分别为1150 nm和1500 nm附近。利用少层黑磷激子构筑的近红外电驱动发光器件拓展了二维材料电致发光器件的波段,为近红外微纳发光器件提供了新的材料与路径。 展开更多
关键词 二维材料 黑磷 激子 近红外 发光二极管
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一种超黑高吸收热控涂层的设计与制备
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作者 刘赛男 贾鑫 +4 位作者 杨爽 汪新智 柯瑞 卢松涛 吴晓宏 《材料保护》 2025年第10期44-51,共8页
针对高精密空间光学系统对杂散光抑制的迫切需求,设计并制备了一种可满足空间服役环境需求的超黑高吸收热控涂层。该涂层采用炭黑纳米颗粒为填料,无机硅酸钾为粘结剂。结合Maxwell-Garnett有效介质模型和Fresnel方程计算出涂层中填料体... 针对高精密空间光学系统对杂散光抑制的迫切需求,设计并制备了一种可满足空间服役环境需求的超黑高吸收热控涂层。该涂层采用炭黑纳米颗粒为填料,无机硅酸钾为粘结剂。结合Maxwell-Garnett有效介质模型和Fresnel方程计算出涂层中填料体积浓度对其光谱吸收特性的影响规律,进一步采用时域有限差分法对具有随机粗糙表面的涂层进行电磁场仿真,并对比分析了不同入射角度下光滑与粗糙涂层的吸收特性,最终制备出了具有超黑高吸收性能的热控涂层。在250~2 500 nm波段范围内,计算结果发现在炭黑体积浓度为2%,表面粗糙度为σ_(rms)=2.0μm时涂层光吸收率在60°入射角下能保持99.9%的光吸收率。且通过实验结果证实,喷涂得到的超黑涂层吸收率在60°大角度下仍具有99.2%的吸收率,与仿真结果高度一致。本研究为空间光学系统先进杂散光抑制涂层的开发提供了有前景的技术方案,对提升成像对比度、探测灵敏度及系统在复杂空间环境下的整体性能具有重要意义。 展开更多
关键词 超黑涂层 消杂光 大角度 吸收率 无机粘结剂
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南京市大气黑碳的吸光性质及其变化特征解析
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作者 徐云龙 单元杰 +1 位作者 张运江 盖鑫磊 《环境工程》 2025年第8期117-128,共12页
研究于2022年3月初至2023年2月底在南京北郊利用黑碳仪(AE33)测定了气溶胶中黑碳(black carbon,BC)的光吸收系数,结合后向轨迹、潜在来源和日均变化,分析其季节变化特征。结果表明:880 nm处BC吸光系数年均值为13.23 Mm^(-1),呈现显著的... 研究于2022年3月初至2023年2月底在南京北郊利用黑碳仪(AE33)测定了气溶胶中黑碳(black carbon,BC)的光吸收系数,结合后向轨迹、潜在来源和日均变化,分析其季节变化特征。结果表明:880 nm处BC吸光系数年均值为13.23 Mm^(-1),呈现显著的季节差异(冬季最高,夏季最低)和日变化特征(双峰型分布,与交通早晚高峰吻合)。370nm短波长下,吸光有机物即棕碳(brown carbon,BrC)的吸光贡献在冬季显著增强(占比38.4%),而夏季占比最低(21.4%)。气溶胶吸收指数(AAE)年均值为1.37±0.19,冬季最高(1.51±0.20)。溯源分析进一步揭示,BC主要来自化石燃料燃烧(68.7%),但在冬季生物质燃烧贡献也较为显著(39.9%)。气象因素中,低温、低边界层高度和低风速易导致BC累积,而相对湿度对BC变化的影响较小。后向轨迹与潜在源分析表明,夏季受局地和区域混合源影响,春秋冬季则受周边区域的影响。研究为南京地区BC污染防控提供了一定的科学依据。 展开更多
关键词 黑碳 吸光性质 来源 季节变化
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超黑材料的设计与应用研究进展
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作者 张天赐 赵伟伟 刘小青 《功能材料》 北大核心 2025年第10期10063-10070,10099,共9页
吸光率大于97%的材料通常被称为超黑材料。由于优异的吸光性能,超黑材料在精密光学、太阳能收集、红外热探测以及军事伪装等领域展现出广泛的应用前景。除了本征黑属性以外,超黑材料还都具有精细设计的表面微观结构,以达到超黑水平,这... 吸光率大于97%的材料通常被称为超黑材料。由于优异的吸光性能,超黑材料在精密光学、太阳能收集、红外热探测以及军事伪装等领域展现出广泛的应用前景。除了本征黑属性以外,超黑材料还都具有精细设计的表面微观结构,以达到超黑水平,这二者是超黑材料必不可少的部分。将目前超黑领域中不同的材料分为金属基超黑、生物质基超黑、碳基超黑和聚合物基超黑。着重阐述了这四类超黑的制备方法、结构设计及性能表征,并对其优缺点分别进行了总结分析。最后对超黑材料的实际应用和未来发展进行了展望。 展开更多
关键词 超黑材料 本征黑 微观结构设计 高吸光率 宽带吸收
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国内外航天器超黑消杂光涂层的研制现状及产业启示 被引量:2
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作者 张北 张家强 +1 位作者 张东 牛鎏 《材料保护》 2025年第1期31-39,共9页
在空间光学系统中,具有高吸收性能的超黑涂层是抑制光学杂散光、提高光学系统检测信噪比和成像质量的关键材料,被广泛应用于航天器星敏感器、空间相机等产品。目前国内外常用的消杂光涂层技术有阳极氧化、超黑Ni⁃P、碳纳米管、黑硅、黑... 在空间光学系统中,具有高吸收性能的超黑涂层是抑制光学杂散光、提高光学系统检测信噪比和成像质量的关键材料,被广泛应用于航天器星敏感器、空间相机等产品。目前国内外常用的消杂光涂层技术有阳极氧化、超黑Ni⁃P、碳纳米管、黑硅、黑漆等,本文对国内外航天器常用消杂光涂层技术以及研制进展进行系统综述,揭示了国内在高性能超黑涂层的工程应用方面仍与国外存在差距,提出应当进一步促进产学研一体化,推进产品的工程转化应用,同时进一步开展耐空间环境的高性能材料研究的发展思路,为我国航天器消杂光涂层研制及产业发展提供启示。 展开更多
关键词 超黑材料 消杂光 涂层 航天器
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不同光质照射福鼎大白茶树对红茶主要生化成分含量的影响
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作者 孔令福 侯佳辉 +4 位作者 涂洁磊 黄胜瑶 崔建成 杜习博 雷凌茜 《云南师范大学学报(自然科学版)》 2025年第5期15-17,70,共4页
利用黄光、红光、蓝光照射福鼎大白茶树,分析不同光质对福鼎大白茶红茶中茶多酚、氨基酸和咖啡碱含量的影响.结果表明,红光增加了茶多酚含量,黄光对茶多酚含量影响较小,而蓝光明显降低了茶多酚含量(约20%);三种光质对氨基酸含量影响较小... 利用黄光、红光、蓝光照射福鼎大白茶树,分析不同光质对福鼎大白茶红茶中茶多酚、氨基酸和咖啡碱含量的影响.结果表明,红光增加了茶多酚含量,黄光对茶多酚含量影响较小,而蓝光明显降低了茶多酚含量(约20%);三种光质对氨基酸含量影响较小;红光明显降低了咖啡碱含量(约25%). 展开更多
关键词 福鼎大白茶 光质 红茶 茶多酚 氨基酸 咖啡碱
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机电作动器故障诊断方法及其可解释性分析
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作者 姚智敏 陈换过 苏世弘 《机电工程》 北大核心 2025年第10期1837-1850,1887,共15页
针对现存机电作动器(EMA)故障诊断方法中决策过程不清晰和可解释性不足的问题,提出了一种基于轻量级梯度提升机(LightGBM)的故障诊断方法,并利用SHAP框架对诊断模型进行了可解释性分析。首先,提取了多源信号的时域和频域特征,并结合随... 针对现存机电作动器(EMA)故障诊断方法中决策过程不清晰和可解释性不足的问题,提出了一种基于轻量级梯度提升机(LightGBM)的故障诊断方法,并利用SHAP框架对诊断模型进行了可解释性分析。首先,提取了多源信号的时域和频域特征,并结合随机森林(RF)和最大互信息数(MIC)对特征进行了筛选,降低了特征集和模型的复杂性;然后,提出了一种基于黑翅鸢优化算法(BKA)的LightGBM故障诊断方法,使用BKA对LightGBM模型的多参数进行了同步优化,对故障类型进行了判断;最后,引入SHAP框架对故障诊断模型进行了可解释性分析,直观展示了故障诊断决策过程及其关键影响因素。研究结果表明:BKA-LightGBM在仿真数据上的诊断准确率可达99.69%,在试验数据上的诊断准确率达到97.60%,不仅在故障识别精度方面表现优越,还能直观揭示特征对模型决策的影响过程和重要性,展现出优异的准确性、鲁棒性和可解释性。 展开更多
关键词 机电作动器 黑翅鸢优化算法 轻量级梯度提升机 可解释性 SHAP框架 随机森林 最大互信息数
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VIIRS夜光影像中农田火像素识别方法
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作者 曹汉瑞 王妍 +3 位作者 李熙 胡申森 邱实 魏英策 《武汉大学学报(信息科学版)》 北大核心 2025年第10期2072-2085,共14页
夜光遥感影像已被广泛应用于人类活动、社会经济等方面的研究。南部非洲的夜光影像上存在烧田产生的农田火像素,这些像素易与城镇灯光像素混淆,干扰了夜光影像在社会经济评估中的应用。以南部非洲的10个大陆国家为研究区域,基于国家极... 夜光遥感影像已被广泛应用于人类活动、社会经济等方面的研究。南部非洲的夜光影像上存在烧田产生的农田火像素,这些像素易与城镇灯光像素混淆,干扰了夜光影像在社会经济评估中的应用。以南部非洲的10个大陆国家为研究区域,基于国家极地轨道伙伴关系卫星(national polar-orbiting partnership,NPP)/可见光红外成像辐射仪(visible infrared imaging radiometer,VIIRS)数据生产的黑色大理石(Black Marble)产品,首先构建了夜光辐亮度时间序列的3个特征;然后采用随机森林分类方法将夜光影像中的像素分为农田火像素、稳定灯光像素和全黑像素;最后采用分层随机抽样,用时间序列夜光辐亮度数据、高分辨率卫星影像和地表覆盖数据对像素分类结果进行精度检验。结果表明,像素分类的总体精度为91.2%,平均生产者精度为91.9%,平均用户精度为91.0%,其中农田火像素分类的生产者精度和用户精度分别为86.4%和92.6%。所提方法可在后续应用中滤除Black Marble产品中的农田火像素,提升夜光影像对非洲社会经济的评估精度。 展开更多
关键词 夜光遥感 NPP/VIIRS black Marble产品 南部非洲 农田火
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