摘要
设计了一款基于双光路荧光强度法的叶绿素a原位传感器。使用430 nm LED作为系统光源。通过参考光路补偿光源变化对测量结果的影响,提高测量准确度,降低维护成本。使用光电二极管作为探测器测量参考光强度和水体在680 nm处的荧光强度。使用锁相放大电路提高传感器的噪声和背景光抑制能力,设计低功耗模式降低传感器的平均功耗。使用不同浓度的叶绿素a溶液测试传感器的性能,测试结果表明传感器在动态范围(0~200μg/L)内的线性度为0.998,测量准确度为±2μg/L,通过与荧光光谱仪进行对比测试传感器的可靠性,测试结果表明两者的相关性为0.94,功耗测试表明传感器的连续工作时间可达5个月以上。
A chlorophyll-a in-situ sensor based on dual-path fluorescence intensity method is presented. A 430 nm LED was used as the light source. To improve the measurement accuracy and reduce the maintenance cost,the influence of the variation of the light source intensity was compensated by the reference path. Photodiodes were used to measure the reference light intensity and the liquid fluorescence intensity at 680 nm. Lock-in amplifier was used to improve the anti-noise ability,and a low-power mode was designed to reduce the power consumption. The performance of the sensor was tested using chlorophyll-a solution with different concentrations. The test results show the linearity of the sensor is 0.998 and the measurement accuracy is ±2 μg/L in the dynamic range(0~200 μg/L). The reliability of the sensor was tested by comparing the sensor with a fluorescence spectrometer,the test results show the correlation between the two instruments is 0.94. The power consumption test shows the continuous working time of the sensor can be more than 5 months.
引文
[1] 杨红生.我国海洋牧场建设回顾与展望[J].水产学报,2016,40(7):1133-1140.
[2] 游桂云,杜鹤,管燕.山东半岛蓝色粮仓建设研究——基于日本海洋牧场的发展经验[J].中国渔业经济,2012,30(3):30-36.
[3] 王志滨,李培良,顾艳镇.海洋牧场生态环境在线观测平台的研发与应用[J].气象水文海洋仪器,2017,34(1):13-17.
[4] 于会娟,王金环.从战略高度重视和推进我国海洋牧场建设[J].农村经济,2015(3):50-53.
[5] 杨红生,杨心愿,林承刚,等.着力实现海洋牧场建设的理念、装备、技术、管理现代化[J].中国科学院院刊,2018,33(7):732-738.
[6] Gregor J,Marsálek B.Freshwater Phytoplankton Quantification by Chlorophyll a:A Comparative Study of in vitro,in vivo and in situ Methods.[J].Water Research,2004,38(3):517-22.
[7] Lamb J J,Eaton-Rye J J,Hohmann-Marriott M F.An LED-Based Fluorometer for Chlorophyll Quantification in the Laboratory and in the Field[J].Photosynthesis Research,2012,114(1):59-68.
[8] Rao G,Lam H,Kostov Y,et al.Chlorophyll and Turbidity Sensor System[P].EP2389447,2014-11-05.
[9] Blockstein L,Yadid-Pecht O.Lensless Miniature Portable Fluorometer for Measurement of Chlorophyll and CDOM in Water Using Fluorescence Contact Imaging[J].IEEE Photonics Journal,2014,6(3):1-16.
[10] Yin G,Zhao N,Shi C,et al.Phytoplankton Photosynthetic Rate Measurement Using Tunable Pulsed Light Induced Fluorescence Kinetics[J].Optics Express,2018,26(6):A293-A300.
[11] Meade M L.Lock-in Amplifiers:Principles and Applications[J].Majalah Lapan,1983,131(3):134.
[12] Wang C,Li D,Zhang L,et al.A Portable Measurement Instrument for the Measurement of Water Body Chlorophyll-a in the Support of Fluorescence Detection[C]//Li D,Chen Y,eds.Computer and Computing Technologies in Agriculture V— 5th IFIP TC 5/SIG 5.1 Conference,CCTA 2011,Proceedings.Springer Berlin Heidelberg,2012:484-494.
[13] Storey R.The Advantages of Chlorophyll Extraction with Alcohol[J].American Biology Teacher,1980,42(3):180-181.
[14] Porra R J.The Chequered History of the Development and Use of Simultaneous Equations for Accurate Determination of Chlorophylls a and b[J].Photosynthesis Research,2002,73(1-3):149-156.
[15] Johan F,Jafri M Z,Lim H S,et al.Laboratory Measurement:Chlorophyll-a Concentration Measurement with Acetone Method Using Spectrophotometer[C]//2014 IEEE International Conference on Industrial Engineering and Engineering Management.IEEE,2014:744-748.
[16] 杨益民.叶绿素a荧光检测仪的设计与开发[D].杭州:浙江大学生物医学工程与仪器科学学院,2011.史正(1994-),男,浙江大学光电科学与工程学院硕士研究生,主要从事环境检测技术方面的研究,21630069@zju.edu.cn;王晓萍(1962-),女,博士,浙江大学海洋学院教授,主要从事环境检测技术、SPR传感技术、电子舌技术及其应用方面的研究,xpwang@zju.edu.cn。