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不同层次天体的质光比研究进展
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作者 钟泽昊 赵刚 《天文学进展》 CSCD 北大核心 2018年第2期81-100,共20页
利用天体的质光比和测光信息可以得到不同层次天体的质量信息,利用恒星的质光关系可以计算单星的质量。星团和星系的表面亮度分布反映其质量分布,因此可以通过研究质光比来了解星团和星系的动力学演化。由于星系中存在大量暗物质,因此,... 利用天体的质光比和测光信息可以得到不同层次天体的质量信息,利用恒星的质光关系可以计算单星的质量。星团和星系的表面亮度分布反映其质量分布,因此可以通过研究质光比来了解星团和星系的动力学演化。由于星系中存在大量暗物质,因此,星系的质光比普遍比星团的大。星系团的质光比普遍比星系的更大,说明星系团中暗物质的比例更高。介绍了恒星、星团、星系、星系群和星系团等不同层次天体的质光比测量方法及其研究进展,并简单阐述这一领域未来的研究方向。 展开更多
关键词 质光关系 质光比 星团 星系群 星系团
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亚湿热气候环境下轻质光伏组件户外实证性能研究
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作者 潘永恒 曾湘安 +3 位作者 李华峰 李烁烁 陈心欣 许楚斯 《环境技术》 2024年第7期77-81,共5页
通过在广州某地搭建轻质光伏组件小型并网发电系统,对光伏组件服役环境进行实时监测和数据采集,同时配置高精度的电气仪表监测该光伏系统的发电性能参数。经过一年期的实证试验,可发现轻质光伏组件系统在一年周期中平均直流PR值约为88.... 通过在广州某地搭建轻质光伏组件小型并网发电系统,对光伏组件服役环境进行实时监测和数据采集,同时配置高精度的电气仪表监测该光伏系统的发电性能参数。经过一年期的实证试验,可发现轻质光伏组件系统在一年周期中平均直流PR值约为88.76,平均交流PR值约为83.43,最大功率Pmax平均衰减1.83%。 展开更多
关键词 亚湿热环境 质光伏组件 发电性能 PR值 IV性能
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光伏组件轻量化发展与研究进展
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作者 郭远帆 卢博 李媛媛 《材料导报》 EI CAS CSCD 北大核心 2024年第S01期16-19,共4页
光伏发电成为最受欢迎的清洁能源之一,光伏组件作为光伏系统中的重要设备之一,随着封装材料和工艺技术的进步,组件也在朝着轻量化的趋势发展,通过减小组件自重,降低对支架系统的载荷,以适应更多的场景和应用环境。然而随着组件质量的减... 光伏发电成为最受欢迎的清洁能源之一,光伏组件作为光伏系统中的重要设备之一,随着封装材料和工艺技术的进步,组件也在朝着轻量化的趋势发展,通过减小组件自重,降低对支架系统的载荷,以适应更多的场景和应用环境。然而随着组件质量的减小,封装材料的改变,组件自身的可靠性面临更高要求。本文就单玻组件、双玻组件和近年来提出的轻质柔性组件各自发展趋势、封装材料、封装结构的特性和可靠性进行了分析,对光伏组件的轻量化发展进行了综述,并提出了今后的发展趋势和方向,以及轻质柔性组件所面临的挑战,为轻质柔性组件的设计开发提供参考。 展开更多
关键词 太阳能 背板 玻璃 质光伏组件 封装结构
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糯质光温敏核不育系闽糯2S的选育与利用 被引量:2
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作者 黄荣华 程祖锌 +2 位作者 林荔辉 章清杞 蔡来龙 《江西农业大学学报》 CAS CSCD 北大核心 2021年第3期504-510,共7页
【目的】选育和利用优质糯稻不育系。【方法】采用350Gy ^(60)Co-γ射线辐照光温敏核不育系6311S干种子,借助淀粉遇KI-I2溶液的显色反应原理,在其M2带胚糙米群体获得糯质基因突变体。经福建、海南异地种植鉴定与选择,育成糯质6311S不育... 【目的】选育和利用优质糯稻不育系。【方法】采用350Gy ^(60)Co-γ射线辐照光温敏核不育系6311S干种子,借助淀粉遇KI-I2溶液的显色反应原理,在其M2带胚糙米群体获得糯质基因突变体。经福建、海南异地种植鉴定与选择,育成糯质6311S不育系,命名为闽糯2S。【结果】除直链淀粉含量差异显著外,闽糯2S与6311S具有相同的生育期,十分相似的农艺性状、花器性状、花粉不育特性以及育性转换特性。【结论】闽糯2S于2020年6月通过福建省农作物品种审定委员会审定,用闽糯2S配制成的优质高产杂交糯稻新组合糯两优8号,于2020年9月通过湖北省农作物品种审定委员会审定。 展开更多
关键词 辐射诱变 质光温敏核不育系 闽糯2S 优质 选育
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基于MOPSO和TOPSIS的多目标优化温室黄瓜光环境调控模型 被引量:3
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作者 李远方 侯军英 +3 位作者 杨永霞 孙章彤 高攀 胡瑾 《农业工程学报》 EI CAS CSCD 北大核心 2023年第19期185-194,共10页
针对在现有温室光环境调控模型中,未考虑光质-光强的协同影响以及净光合速率与光能利用率双优化的问题。该研究面向温室黄瓜的高效补光,提出一种基于多目标优化思想的光质-光强协同调控方法。通过设计多因子耦合的净光合速率试验,获取... 针对在现有温室光环境调控模型中,未考虑光质-光强的协同影响以及净光合速率与光能利用率双优化的问题。该研究面向温室黄瓜的高效补光,提出一种基于多目标优化思想的光质-光强协同调控方法。通过设计多因子耦合的净光合速率试验,获取叶片的净光合速率数据,建立净光合速率模型,并计算叶片尺度的光能利用率;构建光能利用率与净光合速率双优化的多目标优化模型,利用多目标粒子群算法获取非劣解集,基于理想解逼近算法得到光质-光强的调控单点,从而建立设施黄瓜红、蓝光模型。理论验证试验表明,与光合最大补光法相比,净光合速率降低21.39%,需光量降低59.40%;与固定光质0.5和0.8相比,在相同光强下净光合速率依次提升3.66%和9.69%。在此基础上开展实际验证试验,结果表明与固定光质法相比,在耗电量相近的前提下,生理指标均优于固定光质补光法,且在茎粗、干质量以及壮苗指数上存在显著差异;与光合最大补光法相比,生理指标不存在显著差异,且耗电量节省27.43%,表明该研究方法在保证生理指标高水平的前提下,有效节省了光电资源的消耗。该研究方法为设施农业调控提供了新型补光策略,保障了农业生产资源的高效利用。 展开更多
关键词 温室 净光合速率 光能利用率 多目标粒子群算法 逼近理想解算法 质光强协同调控
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关于新型光伏组件安装及运维关键技术的探索实践 被引量:1
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作者 程拥军 严昱 《电气技术与经济》 2023年第9期23-25,共3页
光伏组件的应用越来越广泛,行业技术也在不断更新迭代,市场上相继出现一些新型的光伏组件。这些新型组件的安装技术及运维方式不同于传统的光伏组件,其关键技术需要在光伏项目投建运过程中去探索实践并总结经验,这样才能有效提升光伏电... 光伏组件的应用越来越广泛,行业技术也在不断更新迭代,市场上相继出现一些新型的光伏组件。这些新型组件的安装技术及运维方式不同于传统的光伏组件,其关键技术需要在光伏项目投建运过程中去探索实践并总结经验,这样才能有效提升光伏电站发电效率,保障项目长期收益率。 展开更多
关键词 N型光伏组件 质光伏组件 安装技术 运维技术
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用星系旋转曲线检验不对称引力理论 被引量:1
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作者 王祥玉 吴雪君 须重明 《天体物理学报》 SCIE CAS CSCD 1998年第3期235-242,共8页
本文通过十三个星系的旋转曲线数据,对Mofat不对称引力理论中的两个宇宙普适常数r0,L0进行了检验与讨论,发现在原来假定下,这两个常数的离散程度很大.如果摒弃所有星系质光比都为3的假定,重新确定r0,L0的值并调整... 本文通过十三个星系的旋转曲线数据,对Mofat不对称引力理论中的两个宇宙普适常数r0,L0进行了检验与讨论,发现在原来假定下,这两个常数的离散程度很大.如果摒弃所有星系质光比都为3的假定,重新确定r0,L0的值并调整星系质光比的值,则可与观测数据符合得较好,且调整后的星系质光比的值沿着哈勃序列有减小的趋势.这符合许多人早就得到的结论,因而不对称引力理论在这个意义下是成功的. 展开更多
关键词 星系 旋转曲线 不对称引力理论 质光比
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集成场效应晶体管光调制
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作者 蒋锐 曹三松 《激光技术》 CAS CSCD 北大核心 2004年第2期120-120,共1页
关键词 硅基质光调制器 场效应晶体管 宽硅波导 发射光谱
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Linear and Nonlinear Optical Properties in Spherical Quantum Dots 被引量:1
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作者 Yusuf Yakar Bekir Cakir Ayhan Ozmen 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第6期1185-1189,共5页
We calculate the energy eigenvalues and the sate functions of one-electron Quantum Dot (QD) by using a combination of Quantum Genetic Algorithm (QGA) and Hartre-Fock-Roothaan (HFR) method. The linear and the thi... We calculate the energy eigenvalues and the sate functions of one-electron Quantum Dot (QD) by using a combination of Quantum Genetic Algorithm (QGA) and Hartre-Fock-Roothaan (HFR) method. The linear and the third-order nonlinear optical absorption coefficients for the 1s-1p, 1p-1d, and 1d-1f transitions are examined as a function of the incident photon energy for three different values of the stoichiometric ratio. The results show that the stoichiometric ratio, impurity, relaxation time, and dot size have great influence on the optical absorption coefficients of QDs. 展开更多
关键词 optical properties spherical quantum dot QGA and HFR method
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Preparation and Properties of C-axis Oriented PT/PEK-c Films
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作者 GUOSY RENQ 《Semiconductor Photonics and Technology》 CAS 2001年第4期209-211,229,共4页
The preparation of PT/PEK c films is reported as well as their dielectric and optical properties. The c axis orientation ratio of the films is 68%. Dielectric constant and loss factor at 10 kHz is about 4.023 F/m and ... The preparation of PT/PEK c films is reported as well as their dielectric and optical properties. The c axis orientation ratio of the films is 68%. Dielectric constant and loss factor at 10 kHz is about 4.023 F/m and 0.003, respectively. The refractive indices of the films, n e and n o, are 1.657 3 and 1.627 8 at 0.63 μm wavelength, respectively. The optical band gap of the film with a thickness of 2.33 μm is found to be 3.06 eV. 展开更多
关键词 PT/PEK c films Orientation ratio Dielectric Optical band gap
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Pd catalysts supported on rGO-TiO_2 composites for direct synthesis of H_2O_2: Modification of Pd^(2+)/Pd^0 ratio and hydrophilic property
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作者 Shuying Chen Rui Tu +1 位作者 Jun Li Xiaohua Lu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第3期534-539,共6页
The use of nanostructured composites as catalyst supports is a promising route to prepare catalysts with high selectivity and productivity. In this work, reduced graphene oxide-TiO_2(rGP-x) composites with a variation... The use of nanostructured composites as catalyst supports is a promising route to prepare catalysts with high selectivity and productivity. In this work, reduced graphene oxide-TiO_2(rGP-x) composites with a variation of reduced graphene oxide(rGO) content were synthesized by hydrothermal method. Pd/rGP-x catalysts were prepared in incipient-wetness impregnation method for the direct synthesis of H_2O_2 from H2 and O_2. The morphology and electronic properties of catalysts were investigated by XPS, TEM, and Raman spectroscopy.The ratio of Pd^(2+)/Pd^0 and the hydrophobicity of the catalysts were increased with the rising content of rGO. As the amount of rGO in the catalysts varied in the range of 0.025 wt%–2 wt%, the selectivity of H_2O_2 exhibited a tendency of increasing firstly and then decreasing from 0.1 wt% to 2 wt%. It indicates that good catalytic performance for H_2O_2 synthesis can be achieved only when appropriate amount of rGO is introduced. The H_2O_2 selectivity and productivity of Pd/r GP-0.025 both improved remarkably compared with Pd/P25. This enhancement originated from the combined effects of the proper ratio of Pd^(2+)/Pd^0 and hydrophobicity of the catalyst. 展开更多
关键词 Direct H2O2 synthesis Reduced graphene oxide Hydrothermal Electronic structure Desorption Selectivity
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Aroma Properties of Selected Local Spices of Akwa Ibom State of Nigeria
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作者 E. U .U. Ituen A. F. Alonge 《Journal of Agricultural Science and Technology(B)》 2011年第7期989-997,共9页
Some famous local spices were selected to determine their potentials in terms of their aroma and utilization. They included Tea Bush (Ocimum basilicum), Guinea Black Pepper (Piper guineense), African Pepper (Xylo... Some famous local spices were selected to determine their potentials in terms of their aroma and utilization. They included Tea Bush (Ocimum basilicum), Guinea Black Pepper (Piper guineense), African Pepper (Xylopia aethiopica), Alden Tree (Tetrapleura tetraptera) and the African Meg Nut or Onion Tree (Blighia unijugata). Essential oils were extracted from the samples and used for aroma absorption test in a uv-visible spectrometer V2.03. The intensity of aroma was indicated at some peak values of absorption at particular wavelengths. The compounds responsible for the aroma at this peak values were identified by matching their wavelengths with those of known compounds at similar wavelengths of absorption. Thus, a compound such as Quinoline that has hot strong aroma and little bleaching effect was proved to be present in Guinea black pepper ;at the wavelength of 313.0 nm. Benzene with hot strong aroma and flammable effect was also indicated in this spice at the wavelength of 253.0 rim. Proximate analysis carried out showed that these spices have high nutritive values. Some of them such as Guinea black pepper, African Nutmeg and Ethiopian (African) pepper had high ether extract of 20.01, 25.97 and 31.25 respectively, and could be regarded as oil seeds, they contain much of essential oils. 展开更多
关键词 Absorption WAVELENGTH aroma properties proximate analysis spice.
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Escamoles Ant Eggs Liometopumapiculatumm Source of Metal Ions for Human Health 被引量:1
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作者 Virginia Melo Concepcion Calvo +2 位作者 Tomas Quirino Susana Macin Ileana Muniz 《Journal of Chemistry and Chemical Engineering》 2013年第6期556-559,共4页
The earth crust is believed to be made of a mass of minerals and is matched by their importance in human life. The human body, depend like other leaving organisms, on several minerals as essential constituents of its ... The earth crust is believed to be made of a mass of minerals and is matched by their importance in human life. The human body, depend like other leaving organisms, on several minerals as essential constituents of its existence. Metal ions in foodstuff are in different chemical forms, as inorganic salts or organic molecules or complexes with other compounds such as proteins, amino acids, enzymes and some vitamins, among others, that play an important role in human health. Entomophagy, insect consumption by several ethnic groups in Mexico as cultural tradition since prehispanic era represent an option for population to obtain the minerals needed by the body to keep a good health. Escamoles ant eggs of the Liometopumapiculatum M genus, much appreciated either at rural communities as well as in urban cities, contain minerals with a favorable effect in human health. The aim of this study was to investigate the mineral composition of Escamoles and the benefits which can provide to the human body. Sampling was at an arid region of the Hidalgo state on April 2012. Minerals in dry basis, determined by atomic absorption spectrophotometry, with the exception of phosphorus content, obtained from a triple acid digested extract and determined colorimetrically. Data of mineral analysis in dry basis of Escamoles were: total minerals 5.92%; Na 0.079%; K 0.075%; Ca 0.097%; P 0.701%; Fe 0.021%; Zn 0.035% Cu 0.009%; Mg 0.998%; Mn 0.002%. Minerals quantify are not equal to total ash contained because not all of them were assess determined. Elements concentration depends not only on the total mineral composition of foodstuff the inorganic or organic form or interaction among metal ions, but also on their availability and avail of them. Minerals in Escamoles ant eggs have a considerable influence in the condition of human health. 展开更多
关键词 Escamoles ant eggs metal ions human health.
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利用泵浦探测方法研究菌紫质光循环
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作者 姚保利 徐大纶 《激光与光电子学进展》 CSCD 1995年第A01期152-152,共1页
关键词 泵浦 菌紫质光循环 探测
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宇宙暗物质与万有引力定律
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作者 张橙华 《物理教师》 1996年第4期32-34,共3页
半个世纪以来的天文观测表明在遥远的宇宙里隐藏着看不见的暗物质,而且暗物质可能占宇宙总质量的90%以上。来自空间的电磁波包括无线电波、红外光,可见光以至χ射线与γ射线告诉我们的是各种可见天体与辐射源的信息,暗物质不发射光子,... 半个世纪以来的天文观测表明在遥远的宇宙里隐藏着看不见的暗物质,而且暗物质可能占宇宙总质量的90%以上。来自空间的电磁波包括无线电波、红外光,可见光以至χ射线与γ射线告诉我们的是各种可见天体与辐射源的信息,暗物质不发射光子,只能靠分析万有引力等手段来间接地认识它们。 展开更多
关键词 暗物质 万有引力定律 引力透镜 星系团 质光比 天体系统 宇宙 本星系群 爱因斯坦 开普勒定律
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天体质量的测量
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作者 张玉成 《数理化学习(高中版)》 2004年第21期30-32,共3页
宇宙总是那么奥妙无穷,学过天体运动之后,很多学生不禁要问如何测量出庞大的天体质量呢?下面就给同学们提供几种测量方法.
关键词 天体质星 测量方法 动力学质量法 分光质量法 质光关系法 中学 物理
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The effect of grid shape on the properties of transparent conductive films based on flexographic printing 被引量:2
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作者 LIU Wei FANG Yi +2 位作者 XU Yan Fang LI Xiu LI Lu Hai 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第12期2536-2541,共6页
The effect of grid shape on the properties of transparent conductive films(TCFs) is theoretically analyzed and experimentally verified. The light transmittance by three types of grid shapes: triangle, square and hexag... The effect of grid shape on the properties of transparent conductive films(TCFs) is theoretically analyzed and experimentally verified. The light transmittance by three types of grid shapes: triangle, square and hexagon have been theoretically calculated and simulated. It was found that hexagonal grid unit has the highest light transmittance limit under the practical lattice parameters and its decrease in light transmittance caused by the increase of line width in printing process is the least. The grid of three different shapes with same theoretical transmittance is fabricated through flexographic printing. The result shows that the actual light transmittance of the printed TCFs is lower than its theoretical value because of the inevitable width increase of printed grid lines, with slight difference between the three shapes. However, it is greatly different in terms of conductivity, leading to variation in the quality factor Q(defined as the ratio of light transmittance to total resistance) which represents the performance of TCFs. The Q of hexagonal grid(6.04) is the highest, which is 21% higher than that of the square grid. 展开更多
关键词 metal grid transparent conductive films flexographic printing grid shape quality factor Q
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Effects of Ions Charge-Mass Ratio on Energy and Energy Spread of Accelerated Ions in Laser Driven Plasma
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作者 桑海波 郑世强 谢柏松 《Communications in Theoretical Physics》 SCIE CAS CSCD 2013年第2期205-212,共8页
Effects of ions charge-mass ratio on energy and energy spread of accelerated ions in laser driven plasma are investigated in detail by proposing a simple double-layer model for a foil target driven by an ultrastrong l... Effects of ions charge-mass ratio on energy and energy spread of accelerated ions in laser driven plasma are investigated in detail by proposing a simple double-layer model for a foil target driven by an ultrastrong laser. The radiation pressure acceleration mechanism plays an important role on the studied problem. For the ions near the plasma mirror, i.e. electrons layer, the dependence of ions energy on their charge-mass ratio is derived theoretically. It is found that the larger the charge-mass ratio is, the higher the accelerated ions energy gets. For those ions far away from the layer, the dependence of energy and energy spread on ions charge-mass ratio are also obtained by numerical performance. It exhibits that, as ions charge-mass ratio increases, not only the accelerated ions energy but also the energy spread will become large. 展开更多
关键词 laser driven plasma radiation pressure acceleration ions charge-mass ratio
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A colorimetric and fluorometric fluoride sensor based on a BODIPY-phenol conjugate
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作者 LV YongJun XU Jian +1 位作者 GUO Yong SHAO ShiJun 《Science China Chemistry》 SCIE EI CAS 2011年第5期797-801,共5页
A boradiazaindacenes (BODIPY)-phenol conjugate,1,can act as a colorimetric and fluorometric sensor for sensitive and se-lective measurement of F-over AcO-and H2PO-4 in CH3CN. Sensor 1 gives response to F-in a 1:1 rati... A boradiazaindacenes (BODIPY)-phenol conjugate,1,can act as a colorimetric and fluorometric sensor for sensitive and se-lective measurement of F-over AcO-and H2PO-4 in CH3CN. Sensor 1 gives response to F-in a 1:1 ratio via the deprotonation of the phenolic OH proton,which results in color change from pale yellow to light green and quenching of bright green fluo-rescence. 展开更多
关键词 COLORIMETRIC fluorescence FLUORIDE SENSOR BODIPY
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