Chapters authored
Water Chemical Remediation for Simultaneous Removal of Phosphate Ion and Blue-Green Algae From Anthropogenically Eutrophied Pond
Recent organic pollution is caused primarily by the decay of blue-green algae, Microcystis aeruginosa, which is seriously multiplied due to phosphorus-based anthropogenic eutrophication. In eutrophic water, the phenomenon of pH rising in the surface water occurs due to photosynthesis by M. aeruginosa (rising over pH 10). Such pH value is enough to produce calcium phosphate precipitation. The M. aeruginosa cells form colonies and have the outer layer of which is surrounded by a gelatinous sheath. Thus, we considered simultaneous removal of phosphate ion and blue-green algae using calcium chloride from water surface of eutrophic pond. In the present chapter, a simultaneous removal method employing water chemical remediation (WCR) is described. In this method, a flow system was constructed by equipment of a calcium chloride injector and a sand filtration column. As a result, both calcium phosphate and agglutinated algae could be removed from the eutrophic pond water. These water nutrients are removed, phosphorus is concerned about exhaustion as a resource, and the collected algae can be used in various ways as biomass resources. Thus, our system showed the future ability to improve water quality, to remove contaminants, and to recover nutrients from eutrophic water.
Part of the book: Water Chemistry
Developmental Studies on Practical Enzymatic Phosphate Ion Biosensors and Microbial BOD Biosensors, and New Insights into the Future Perspectives of These Biosensor Fields
This chapter summarizes the developmental studies on environmental biosensors of enzymatic phosphate ion (Pi) biosensors for eutrophication and microbial biochemical oxygen demand (BOD) biosensors for organic pollution. In particular, an author focuses on the developmental studies that the author principally conducted, and describe the history and the insights into the future of these fields of environmental biosensors. In our developmental studies on the enzymatic Pi biosensors, we fabricated automatic instruments of a desktop-type and a submersible buoy-type, which was fabricated for remote biosensing of dam water. These instruments employed a luminol-chemiluminescence flow injection analysis (CL-FIA) system and enabled to have practical performances in precise Pi determination, operational stability, and accurate bioavailable Pi measurements. In the microbial BOD biosensor development, the author considered to apply the FIA concept enabling highly repeatable measurements to absorptiometric BOD measurements. Both precise temperature control and accurate time control to incubate measurement mixture of budding yeast cell suspension containing redox color indicator and sample enabled to obtain the highly repeatable results that led to highly sensitive BOD measurements. Looking back on our developmental studies, what the author was thinking at the time and the results obtained are described. Finally, the author discusses the developmental trends of these biosensor fields and new insights into the future perspectives.
Part of the book: Biosignal Processing