A Study of Ultrasonic Effects on the Marine Biofouling Organism of Barnacle, Amphibalanus Amphitrite Guo Shifeng National Unive

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A Study of Ultrasonic Effects on the Marine Biofouling Organism of Barnacle, Amphibalanus Amphitrite Guo Shifeng National Unive A STUDY OF ULTRASONIC EFFECTS ON THE MARINE BIOFOULING ORGANISM OF BARNACLE, AMPHIBALANUS AMPHITRITE GUO SHIFENG NATIONAL UNIVERSITY OF SINGAPORE 2012 A STUDY OF ULTRASONIC EFFECTS ON THE MARINE BIOFOULING ORGANISM OF BARNACLE, AMPHIBALANUS AMPHITRITE GUO SHIFENG (B. ENG. CQUT, M. ENG. CQU) A THESIS SUBMITTED FOR THE DEGREE OF DOCTOR OF PHILOSOPHY DEPARTMENT OF MECHANICAL ENGINEERING NATIONAL UNIVERSITY OF SINGAPORE 2012 Declaration Declaration I hereby declare that this thesis is my original work and it has been written by me in its entirety. I have duly acknowledged all the sources of information which have been used in the thesis. This thesis has also not been submitted for any degree in any university previously. Guo Shifeng 21 November 2012 I Acknowledgements Acknowledgements First of all, I would like to express my sincere gratitude to my supervisors, Associate Prof. Lee Heow Pueh and Prof. Khoo Boo Cheong, for providing me the precious opportunity to study under their supervision. In the past four years, I indeed have learnt and benefitted from their profound knowledge and strict academic attitude, which will benefit my whole life. It is impossible for me to finish my thesis without their invaluable guidance, sincere support, and continuous encouragement. Special thanks to Associate Prof. Lim Siak Piang and Lim Kian Meng for their help and suggestions in my research. I would also like to express my appreciation to Dr. Serena Lay Ming Teo for her sincere guidance and invaluable suggestions on my project. I would like to thank her for providing me all the convenience and facilities for the barnacle experiments. I gratefully acknowledge the financial support from National University of Singapore through the Research Scholarship, without which it would have not been possible for me to pursue my degree in NUS. I would like to thank Ms. Serina Siew Chen Lee from TMSI (Tropical Marine Science Institute) on the barnacle cyprids culture. I would also express my sincere thanks to my fellow lab mates and friends Zhuang Han, Liu Yang, Tse Kwong Ming, II Acknowledgements Zhu Jianhua, Chen Xiaobin, Thein Min Htike, Arpan Gupta, Wu Liqun, Liu Yilin, and Sun Qiang for their help in the past four years. I would like to thank the lab officers of dynamic lab for providing me the convenience and help for my experiments. Finally, I would express my deepest gratitude and love to my families for their continuous support and sincere encouragement. III Table of contents Table of Contents Declaration………………………………………………………………….………..I Acknowledgements .................................................................................................... II Summary………… ................................................................................................ VIII List of Tables. ............................................................................................................. X List of Figures ........................................................................................................... XI Nomenclature ......................................................................................................... XVI Acronyms……… .................................................................................................. XVII Chapter 1. Introduction ......................................................................................... 1 1.1. Marine biofouling .............................................................................................. 1 1.2. Development of fouling ..................................................................................... 2 1.3. Marine fouling organisms .................................................................................. 4 1.3.1. Bacteria ....................................................................................................... 4 1.3.2. Diatom ........................................................................................................ 5 1.3.3. Green alga ................................................................................................... 5 1.3.4. Mussel ......................................................................................................... 6 1.3.5. Barnacle ...................................................................................................... 6 1.4. Strategies of fouling control ............................................................................. 10 1.4.1. Biocides based methods ............................................................................ 11 1.4.2. Non-toxic coatings .................................................................................... 13 1.4.3. Physical methods ...................................................................................... 17 1.5. Effect of ultrasound on biofouling ................................................................... 18 1.5.1. Ultrasound applications on biofouling prevention .................................... 19 1.5.2. The application of ultrasound on barnacle prevention .............................. 20 1.6. Scope and objective of study ........................................................................... 20 1.7. Thesis organization .......................................................................................... 21 IV Table of contents Chapter 2. Effect of ultrasound on cyprids and juvenile barnacles ................ 23 2.1. Introduction ...................................................................................................... 24 2.2. Materials and methods ..................................................................................... 26 2.2.1. Ultrasonic irradiation system .................................................................... 26 2.2.2. Cyprid settlement and mortality assay ...................................................... 27 2.2.3. Cyprid exploration behavior assay ............................................................ 28 2.2.4. Barnacle growth assay .............................................................................. 29 2.2.5. Statistical analysis ..................................................................................... 30 2.3. Results .............................................................................................................. 30 2.3.1. Cyprid settlement assay ............................................................................ 30 2.3.2. Cyprid mortality ........................................................................................ 32 2.3.3. Cyprid exploration behavioral assay ......................................................... 33 2.3.4. Barnacle growth assay .............................................................................. 35 2.4. Discussion ........................................................................................................ 36 2.5. Conclusion for chapter 2 .................................................................................. 40 Chapter 3. The exploration of the mechanism of ultrasound on barnacle cyprid settlement inhibition ..................................................................................... 41 3.1. Introduction ...................................................................................................... 42 3.2. Material and methods ....................................................................................... 43 3.2.1. Ultrasonic irradiation system .................................................................... 43 3.2.2. Cyprid settlement and mortality assay ...................................................... 44 3.2.3. Cyprid inhibition mechanism investigation .............................................. 44 3.2.4. Ultrasonic emission spectrum analysis and cavitation energy estimation 45 3.2.5. Data analysis ............................................................................................. 47 3.3. Results .............................................................................................................. 48 3.3.1. Cyprid settlement assay .......... …………………………………………..48 3.3.2. Settlement and mortality comparison between FSW and PDFSW .......... 50 V Table of contents 3.3.3. Ultrasonic spectrum and cavitation energy analysis ................................. 52 3.4. Discussion and conclusion for chapter 3 .......................................................... 54 Chapter 4. Investigation of low intensity ultrasound on barnacle cyprid settlement…… ........................................................................................................... 59 4.1. Introduction ...................................................................................................... 60 4.2. Material and methods ....................................................................................... 61 4.2.1. Ultrasound irradiation setup ...................................................................... 61 4.2.2. The choice of ultrasound amplitude .......................................................... 62 4.2.3. Cyprid settlement and mortality assay ...................................................... 64 4.2.4. Effect of low intensity, continuous ultrasound on cyprid behavior .......... 65 4.2.5. Substratum vibration and acoustic pressure analysis ................................ 66 4.2.6. Intermittent ultrasonic irradiation ............................................................. 67 4.2.7. Efficient frequency band on cyprid settlement ........................................
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