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Performance Evaluation of Inherent Optical Property Algorithms and Identification of Potential Water Quality Indicators Using GCOM-C Data in Eutrophic Lake Kasumigaura, Japan
Get PDFLake Kasumigaura, one of Japan’s largest lakes, presents significant challenges for remote sensing due to its eutrophic conditions and complex optical properties. Although the Global Change Observation Mission-Climate (GCOM-C)/Second-generation Global Imager (SGLI)-derived inherent optical properties (IOPs) offer water quality monitoring potential, their performance in such turbid inland waters remains inadequately validated. This study evaluated five established IOP retrieval algorithms, including the quasi-analytical algorithm (QAA_V6), Garver–Siegel–Maritorena (GSM), generalized IOP (GIOP-DC), Plymouth Marine Laboratory (PML), and linear matrix inversion (LMI), using measured remote sensing reflectance (Rrs) and corresponding IOPs between 2017–2018. The results demonstrated that the QAA had the highest performance for retrieving absorption of particles (ap) with a Pearson correlation (r) = 0.98, phytoplankton (aph) with r = 0.97, and non-algal particles (anap) with r = 0.85. In contrast, the GSM algorithm exhibited the best accuracy for estimating absorption by colored dissolved organic matter (aCDOM), with r = 0.87, along with the lowest mean absolute percentage error (MAPE) and root mean square error (RMSE). Additionally, a strong correlation (r = 0.81) was observed between SGLI satellite-derived remote-sensing reflectance (Rrs) and in situ measurements. Notably, a high correlation was observed between the aph (443 nm) and the chlorophyll a (Chl-a) concentration (r = 0.84), as well as between the backscattering coefficient (bbp) at 443 nm and inorganic suspended solids (r = 0.64), confirming that IOPs are reliable water quality assessment indicators. Furthermore, the use of IOPs as variables for estimating water quality parameters such as Chl-a and suspended solids showed better performance compared to empirical methods
Membrane separation of dispersion of PbS colloidal quantum dots with iodide ligands
Get PDFWe have succeeded in membrane separation to classify PbS colloidal quantum dots (CQDs) with iodide ligands, which have the potential to significantly improve the performance of many optoelectronic devices such as solar cells. CQDs are expected to be applied in various fields due to their unique features; however, a method for mass-producing uniform CQDs has not yet been established, and the high manufacturing costs resulting from small-scale production are hindering social implementation. We have proposed the membrane separation process as an alternative to conventional centrifugation and demonstrated an acceleration and improved efficiency of the separation processes, thereby eliminating the bottlenecks. Size separation of CQDs with iodide ligands (I-CQDs) using membrane filtration has remained particularly challenging due to their inevitable adsorption to the membrane. In this work, I-CQDs were successfully withdrawn to the filtrate without adsorption by dispersing them in a quaternary mixed solvent that satisfies the adsorption-inhibiting conditions proposed in previous studies, which are based on Hansen solubility parameters. Our membrane separation technology will become the basis for the low-cost production of I-CQDs
Preparation, crystallographic characterization, and analysis of 3-amino-1,2,4-triazolium nitrate synthesized via electrolytic oxidation with ammonium nitrate
Get PDFElectrolytic oxidation of 3-amino-1,2,4-triazole with ammoniumnitrate as electrolyte yielded single crystals of 3-amino-1,2,4-triazolenitrate salt, which was previously reported but lacked structural andthermal data. In this work, we employ thermal and other analyses tobetter characterize the aforementioned salt. The salt released sig-nificantly more heat (2359 J/g) than the raw materials (909, and1171 J/g, respectively) or their mixture (2112 J/g) in SC-DSC mea-surements. TG-DTA measurements revealed that a higher onsettemperature of weight loss for the salt, although complete gasifica-tion was unobserved. Crystallographic data enabled calculations ofthe detonation velocity, which ranged from 7834 to 8101 m/s
Development of highly functional three-dimensional tissue models using collagen
Get PDF横浜国立大学博士（工学）Doctor of Engineerin
Robust transfer of a quantum state from an absorbed photon into a diamond spin
Get PDFConversion of a quantum state from a flying qubit to a memory qubit is crucial for distributed quantum computing. However, this requires precise spatiotemporal or frequency/phase alignment. Here, we experimentally demonstrate quantum teleportation-based state transfer from a photon into a spin in a nitrogen-vacancy center in diamond robust against both spectral and temporal errors. The achieved fidelity exceeds 0.94 within a frequency error of 100 MHz and 0.93 within an arrival-time error of 100 ns. This achievement could enable extraordinarily robust entanglement generation between remote quantum memories compared with the conventional photon-interference-based approaches and paves the way for stable quantum networks
