Synthesis method of inorganic compounds from seawater or raw materials originating from seawater and its characterization were reviewed. The inorganic compounds to be introduced are Layerd double hydrate （LDH）, Northpite （Na₃Mg(CO₃)₂Cl）, Calcium carbonate （CaCO₃） and protodolomite and Dolomite （CaMg(CO₃)₂). The effects of the synthetic conditions on the products and the functionality of these materials are described. Therefore, the useful material production form seawater is important to continue preventing poor resource for Japan. Here's a brief description of the details.

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Neonicotinoid insecticides （NEOs） are widely used in many agricultural products. However, it has been pointed out that it may flow into rivers, lakes, and coastal areas and affect organisms inhabiting those environments. In this study, the effects of exposure to NEOs at concentrations and exposure periods observed in rivers, waterways and agricultural drainage channels around rice paddies, where Japanese killifish (Oryzias latipes) inhabit, on their anxiety behavior were assessed by light/dark preference tests. We also examined whether or not the anxiety behavior recovered when reared in clean water after exposure to NEOs. Japanese killifish were divided into seven groups of seven males and females each as follows and reared for one week: pesticide-free （Control）, thiamethoxam （THM） exposure; 10 and 200 μg/L, dinotefuran （DIN） exposure; 6 and 120 μg/L, fipronil （FIP） exposure; 1 and 20 μg/L. Light/dark preference tests were conducted immediately before exposure, one day and one week after exposure to measure the percentage of time spent on a black background （Choice index） and the number of times the fish moved between the black and white demarcation line. After the oneweek exposure test, the Japanese killifish were again subjected to the light/dark preference test after two weeks in clean water to determine any behavioral changes. Before pesticide exposure, Japanese killifish spent most of the time in the dark, but one and seven days after exposure to low and high concentrations of THM and DIN, their dark selectivity was significantly lower than that of the control group. Similar changes were also observed in individuals exposed to FIPs. Furthermore, when the killifish were returned to clean water seven days after exposure and kept for at least two weeks, dark selectivity increased (recovered) again in the FIP-exposed group, whereas dark selectivity did not recover in both sexes in the groups exposed to THMs and DINs. In other words, the effects of NEOs exposure are irreversible or long-lasting, and once exposed, even if the animals return to clean water afterwards, the effects will continue for a long period of time for aquatic organisms, and there is concern about the effects on the ecosystem.

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Adsorption of PGMs, Rh, Ir, and Ru, on sulfur-impregnated charcoal, which is prepared from domestic biomass resource, bamboo, via pyrolysis after sulfur-immersion, was examined to apply for PGMs recovery from wastewater. Sulfur-impregnated bamboo charcoal can adsorb Ir and Ru, indicating higher adsorption capacity for Ir (12.2 mg/g) and Ru (15.9 mg/g) than commercial activated carbon, while Rh can't be adsorbed.

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　Bipolar membrane electrodialysis (BPMED) can simultaneously generate acid and alkali solutions. One of the issues for BPMED is low current efficiency for acid/alkali production due to proton leakage from anion exchange membranes (AEMs). In this study, BPMED was performed using different AEMs and salt solutions to investigate the effect of AEM structure and salt solution on current efficiency. When using NaCl as the salt solution, a higher current efficiency was obtained in BPMED using a proton-blocking AEM compared with the standard AEM, although little difference was observed between the two AEMs when using Na₂SO₄.

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Chemical cross-linking combined with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) is a simple way to analyze oligomerization and complex formation of proteins. However, cross-linked proteins with a large molecular mass, for example with molecular weight greater than ∼400 kDa, show slow mobility and tend to stack in loading area with poor resolution. Agarose gel electrophoresis (AGE) may be more suitable, due to a large pore size of the agarose, to analyze proteins as well as DNA fragments, especially for large macromolecules and their complexes. Here, we expressed and purified recombinant ClpB chaperone protein (homologue of eukaryotic HSP104) derived from moderate halophile and analyzed the purified protein by SDS-PAGE and SDS-AGE. Chemical cross-linking and SDS-AGE analysis clearly demonstrated hexameric assembly of ClpB subunit protein. Heat-denaturation profile of the ClpB with native-AGE analysis done without SDS suggested that ClpB protein was denatured at around 50 °C.

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　Isobutanol is attracting attention as a biofuel because of its higher energy density and lower hygroscopicity compared with ethanol. The utilization of seawater in fermentation can potentially reduce the need for freshwater and trace minerals during isobutanol production. Here, we describe isobutanol production using seawater. When an isobutanol-producing Escherichia coli strain was cultured using 40 % seawater as the source of trace minerals, 4.93 g/L isobutanol was produced, with a theoretical yield of 66 %, consistent with the yield obtained using synthetic medium with trace minerals. This result suggests that seawater is a potentially useful medium component for isobutanol production.

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To elucidate the detailed structure of bromide ions （Br） incorporation in sodium chloride （NaCl） crystals, NaCl crystals were prepared with higher incorporated concentrations of Br than conventional ones, and analyses of the Br's presence forms were conducted. Br incorporated NaCl crystals with the concentrations of Br atoms up to 7 % were prepared using a stirred vacuum evaporative crystallization apparatus. Through X-ray diffraction analysis, single-crystal X-ray diffraction analysis, and X-ray absorption fine structure analysis on these high Br incorporated NaCl crystals, we deduced that Br atoms were integrated into the NaCl crystal as substitution-type lattice defects, with Br atoms replacing chloride atoms in the crystal lattice. Additionally, stability calculations of Br arrangement structure in Br incorporated NaCl crystals were performed using first-principles calculations, revealing that the geometric arrangement of substituted Br has minimal impact on the stability of the crystal structure. Consequently, we concluded that there was no regularity in the arrangement of Br incorporated into NaCl crystals.

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　Researches are underway to create functional particles with high added value through crystallization processes using concentrated seawater after salt production, such as bittern, as a raw material. To produce highly functional particles through the crystallization process, it is necessary to develop a crystallization field that is different from the usual one. Crystallization methods utilizing the liquid-liquid phase separation (LLPS) phenomenon that occurs during anti-solvent crystallization have garnered attention. The control of crystal properties using LLPS is promising not only for organic compounds but also for inorganic compounds such as seawater resources. To achieve the desired crystal particles in such processes, it is necessary to design the process considering mass transfer across the solution/anti-solvent interface. However, the molecular level mechanisms of mass transfer at the interface in LLPS systems remain largely unexplored. Herein, we used molecular dynamics simulations to investigate solvent diffusion and the resulting changes in solution structure in the typical LLPS system of water (anti-solvent)-ethanol (good-solvent)-butylparaben (solute). The results indicated that the presence of butylparaben as the solute in the miscible water-ethanol system alters the diffusion behavior of both solvents. At the interface between the butylparaben-ethanol solution and water, a strongly localized solvent layer was observed. Furthermore, compared to previous studies, it was found that the formation and time dependent changes of the liquid-liquid interface and its structure vary depending on whether the system is miscible, immiscible, or undergoes LLPS. In other words, even in the same antisolvent crystallization process, the changes in supersaturation vary by system, suggesting that these variations can affect the morphology of the precipitated crystals.

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Au-loaded sulfur-impregnated charcoal was prepared from biomass waste bamboo and applied to solar absorbers for solar desalination. The evaporation rate of carbonaceous material was higher than that of raw bamboo, that of sulfur-impregnated carbon was higher than that of bamboo charcoal and commercial activated carbon due to sulfur impregnation, and that of Au-loaded sulfur-impregnated charcoal was the highest due to the Au particles on the charcoal surface. These results suggest that Au-loaded sulfur-impregnated charcoal has the potential to be used for solar evaporation.

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　Electrodialysis (ED) utilizes ion-exchange membranes (IEMs) for ion separation and salt concentration. To enhance the efficiency of ion separation and salt concentration in ED, analyzing the permeability of ions through the membranes is essential. In this study, the ion concentration and ion mobility of halide ions in IEMs were calculated using monovalent selective anion-exchange membranes with two base materials to analyze the ion transport mechanism. Results showed that the mobility of the iodide ions in the membranes was the lowest among all the halide ions. By contrast, the iodide ion concentration in each membrane was higher than that of the chloride ions in the mixed KCl and KI solutions, proving that iodide ions have a considerably higher affinity than chloride ions.

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We established capillary zone electrophoresis (CZE) for the simultaneous determination of bromide (Br^－), iodide (I^－), nitrite (NO₂^－), and nitrate (NO₃^－) in salts. To accomplish the simultaneous determination, 10 mM cetyltrimethylammonium chloride (CTAC) was added to the background electrolyte (BGE). The interaction of these anions with CTAC was utilized to adjust the electrophoretic mobilities of the anions. The achieved limits of detection (LOD, signal-to-noise ratio (S/N) = 3) and limits of quantification (LOQ, S/N ＝ 10) were respectively 0.73 and 2.4 mg/L for Br^－, 0.079 and 0.26 mg/L for I^－, 0.049 and 0.16 mg/L for NO₂^－-N ( as N), and 0.039 and 0.13 mg/L for NO₃^－-N. The respective values of the relative standard deviation (RSD, n ＝ 4) of the peak area, peak height, and migration time were 5.2, 1.9, and 0.37 ％ for Br^－ (10 mg/L), 3.5, 5.2, and 0.45 ％ for I^－(1.0 mg/L), 0.98, 1.9, and 0.42 ％ for NO₂^－ (1.0 mg/L), and 2.3, 1.3, and 0.40 ％ for NO₃^－(1.0 mg/L). Linear calibration graphs were obtained for these analytes using both the peak area and peak height （correlation coefficients, 0.9976‒0.9999). The proposed method was used to find the analytes in salt samples including seaweed salts, sea salts, and rock salts. The salts used for this experiment contained 144‒1490 mg/kg of Br^－, 3.85‒48.0 mg/kg of I^－, and 1.46‒2.65 mg/kg of NO₃^－-N. NO₂^－ was not detected from any sample. The CZE results for the analytes agreed with those obtained using ion chromatography (IC). The recoveries were 89.4‒116 ％ when analyzing salt solutions with 0‒15.0 mg/L Br^－, 0‒1.50 mg/L I^－, NO₂^－, and NO₃^－.

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A HPLC method has been developed that can easily and sensitively separate and analyze amyloid-β aggregates. In this method, PTFE tubing (1000 mm × 0.50 mm i.d.) is used as the separation field. Furthermore, thioflavin T, a fluorescent detection reagent for amyloid fibrils, was added to the mobile phase. In this method, separation and labeling are carried out within a single channel from the sample injector to the detector, making it possible to achieve selective and highly sensitive online detection. Furthermore, the simulation and the experimental results suggest that the separation mechanism of this method may involve the Tubular Pinch Effect, a phenomenon in fluid dynamics. These results suggest that this method may be applicable to amyloid fibrils formed by proteins other than amyloid-β.

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