Pathological activation of renal angiotensin II （Ang II） type 1 receptor （AT1R） signaling stimulates renal tubular sodium transporters including epithelial sodium channel to increase renal sodium reabsorption. In the course of an investigational search for a means to functionally and selectively modulate AT1R signaling for that purpose, a molecule directly interacting with the carboxyl-terminal cytoplasmic domain of AT1R was identified by employing yeast two-hybrid screening of a mouse kidney cDNA library and named AT1R-associated protein （ATRAP）. We showed that ATRAP promotes constitutive AT1R internalization so as to inhibit pathological AT1R activation in response to certain stimuli. In the kidney, ATRAP is abundantly distributed in epithelial cells along the renal tubules. The results employing genetic engineered mice with modified ATRAP expression showed that ATRAP plays a key role in the regulation of renal sodium handling and the modulation of blood pressure in response to pathological stimuli such as chronic Ang II infusion, dietary high salt loading and 5/6 nephrectomy, and suggest ATRAP to be a target of interest.

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Structures of small sodium halide nanocrystal（cluster）cations and anions, Na_nF_n－1^＋, Na_nI_n－1^＋, Na_n－1F_n^－, and Na_n－1I_n^－, have been studied by ion mobility mass spectrometry coupled with quantum chemical calculations. In this spectrometry, structural information of atomic and molecular cluster ions was obtained from the measurement of collision cross sections of the ions with a buffer gas in an ion drift cell. As a result of the comparison between the experimental cross sections thus measured and those obtained by theoretical calculations, it was found that the Na_nF_n－1^＋ cluster ions have substructures of bulk face-centered-cubic crystals in most of the cluster size. Among such structures, we predominantly observed cuboid ions with near regular hexahedron such as n＝14（3×3×3）and 23（3×3×5）as magic numbers in the mass spectra. In addition, non-rock-salt “cage” type structures in which one sodium atom is encapsulated into the sodium fluoride cuboid lattice were also found to be stable for n＝7 and 10. Also the stable geometric structures of above four cluster systems were examined systematically in order to obtain the dependence of composite ion sizes on the stable structures. As for the Na_n－1F_n^－ anions and the Na_nI_n－1^＋ cations, cage type structures similar to those of Na₇F₆^＋ and Na₁₀F₉^＋ were observed at n＝7 and 10. However, similar cage structures were not detected for n＝7 and 10 of Na_n－1I_n^－ anions. This result indicates that the cage structures are sensitive to the radius of caged ions（excess atomic ions）: Inclusion of I^－（ionic radius of 2.06 Å）causes large distortion in the structure, whereas they are stable for small caged ions such as Na^＋（1.16 Å）and F^－（1.19 Å）. The experiment of water and methanol adsorption reactions on Na_nF_n－1^＋ ions also showed that the water molecule is highly reactive at specific cluster size, e.g., n＝13 and 22.

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In order to build a utilization system of seawater resources based on the desalination and salt production process and to prevent scaling in reverse osmosis and electrodialysis units, a recovery and upgrading method for calcium（Ca） and magnesium （Mg） from the concentrated brine discharge from salt manufacture in Japan was investigated. The reactive crystallization technique of carbonate using carbon dioxide （CO₂） bubbling is effective for a separation/recovery method of the dissolved Ca^2＋ and Mg^2＋ in the concentrated brine, because the solubility of carbonate is lower than the solubility of hydroxide in the solution at a pH range below 8.0. Especially, dolomite （CaMg（CO₃）₂）, which is double salt of calcium carbonate and magnesium carbonate, has numerous applications as the manufacture of refractories, as neutralizer of soil acidity in agriculture, as mineral supplement for food and drug, etc.. CaMg（CO₃）₂ has crystal structure derived from that of calcite by ordered replacement Ca^2＋ in calcite by Mg^2＋. To improve the functionality of crystal for the better CaMg（CO₃）₂ utilization, it is essential to gain access to the Mg/Ca ratio of 1.0 and to reduce the particle size in the crystallization process. Generally, high concentrations of Ca^2＋, Mg^2＋ and CO₃^2－ are necessary for the production of CaMg（CO₃）₂ with a Mg/Ca ratio of 1.0, because the Mg/Ca ratio increases with increasing the supersolubility product in the bulk solution. In this study, the micron-scale bubble formation technique that enables the generation of regions with a higher ion concentration around the minute gas-liquid interfaces was applied to the reactive crystallization of CaMg（CO₃）₂. In the regions near the minute gas-liquid interfaces, Ca^2＋ and Mg^2＋ accumulate because of the negative electric charge on the microbubble surface, and the concentration of CO₃^2－ increases because of the acceleration of CO₂ mass transfer caused by minimizing the bubble diameter; hence, the fine particles of CaMg（CO₃）₂ with a high Mg/Ca ratio can be expected to crystallize. At a reaction temperature of 298 K and reaction pH of 6.8, CO₂ bubbles with an average diameter（d_bbl） of 40 - 2000 μm were continuously supplied to the concentrated brine coming from salt manufacture discharge and CaMg（CO₃）₂ was crystallized within the reaction time（t_r） of 120 min. Microbubbles with a d_bbl of 40 μm were generated using a self-supporting bubble generator by the shear of the impeller and a negative pressure owing to high-rotation. For comparison, the bubbles with a d_bbl of 200, 300, 800 or 2000 μm were obtained using a dispersing-type generator. Consequently, minimizing the bubble formation accelerated remarkably the crystallization of CaMg（CO₃）₂ fine particles with an average size of about 2.0 μm and decreased t_r necessary for the achievement of Mg/Ca ratio of 1.0.

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To create the comprehensive utilization system of seawater resources based on the salt production process, the utilization method of dissolved bromine （Br） in the discharge concentrated brine of salt manufactory in Japan was developed. In the existence process, Br is recovered by a blowout method with Cl₂ gas bubbling from the removed K⁺ bittern as the liquid Br₂, which is used to the chemical reagents in fine chemical field so as the catalyst, medicinal drug, inorganic material and pesticide. On the other hand, the oxidation products of Br has the various forms so as the hypobromous acid （HBrO）, bromous acid （HBrO₂） and bromic acid （HBrO₃）, and it’s application for the water purification process can be expected. For example, HBrO has a highest oxidation potential for the organic compounds, is obtainable by the ozone （O₃） oxidation reaction of dissolved Br in aqueous solution. In this paper, when ozone/oxygen （O₃/O₂） minute-bubbles were supplied to seawater or NaBr, the influences of the dissolved each salt on the generation of oxygen species （OS） were investigated. The concentration of oxygen species in aqueous solution was determined by colorimetric method. As the results, the solution concentration of total oxygen species （C_OS） in modified seawater or 1.0 mmol/l NaBr solution during the supplying O₃/O₂ minute-bubbles was increased approximately 1.3-times compared with ion-exchanged water at a reaction time of 120 min. Additionally, when the O₃/O₂ minute-bubbles were supplied into 5.0 mmol/l methylene blue （MB） solution, the initial decomposition rate of MB was increased approximately 1.2 times by adding NaBr with concentration of 1.0 mmol/l. Consequently, it seems that the improvement of the organic compound decomposition was induced by presence of Br^- ion during O₃/O₂ minute-bubble supply.

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We describe production of Fleur de sel in the solar saltponds of Castro Marim （Portugal） where the local producers reoriented and substantially increased output of this variety of salt. Indeed this culinary specialty is commercialized for a price order of magnitude higher than coarse marine salt which traditionally dominated the production. Because of a complete lack of published information on that subject the present study aims to elucidate factors, which influence the quality and characteristics of the end product. Crystals size, and density of Fleur de sel samples, collected during the period of 70 days in an artisanal salt unit, were studied. The study resulted in a classification of 3 types of crystals according to their size. Category A was attributed to the biggest crystals, with surface ranging from 18 to 24 mm², considered as the best quality crystals taking into account market requirements. Their formation took place in the following atmospheric conditions: air temperature of 29.6 ℃; relative humidity of air of 40.3 ％; southern wind direction and speed of 6.0 knots; solar radiation of 31,227 KJ/m²; and, an evaporation rate of 1.38 mm/day. Main physicochemical parameters of the brine measured during the formation hours of the biggest crystals were significantly different from those prevailing during the formation of other two categories of crystals. Typical values of the measured parameters corresponding to the best quality crystals were: surface electric conductivity （EC） of 215.32 mS/cm and bottom EC of 216.76 mS/cm; surface temperature of 37.16 ℃ and bottom temperature of 37.28 ℃. The worst quality （C） formed at lowest values of EC and temperature with a mean surface and bottom EC of 200.15mS/cm and 196.86mS/cm, respectively; and 32.45 ℃ and 32.75 ℃ surface and bottom temperatures, respectively. Moreover, during the formation of category A crystals the difference between surface and bottom temperature was the lowest and bottom EC was higher than surface EC. 1 gram of category C crystals contained 156.51（13.59 St Dev） particles, while category A samples contained 96.73（7.11 St Dev） particles. The former results should be considered when focusing on the production of Fleur de sel, by adjusting some of the described parameters, such as the brine characteristics according to the weather forecast or on a real time basis.

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In this study, an accelerated method to crystallize well-formed pyramidal crystals of salt is achieved. The square pyramidal crystals of salt, Fleur de Sel salt are known for their unique crystal structure and used in specialty gourmet foods. The natural crystallization conditions include hot summer days on the surface of ponds containing concentrated sea water. The current study has established a controlled production of pyramidal crystals as an alternate to natural crystallization which is only possible in summer weathers. A saturated solution of salt （brine） is prepared by dissolving sea salt in water. This brine is evaporated in an open crystallizer by gentle evaporation with heating from bottom of the crystallizer. Temperature plays an important role in formation of pyramidal crystals. It was noted that a meta-stable condition in brine for the nucleation and crystal growth is achieved between 55 to 65 ℃ temperature range. Brine purification was also applied for removal of sulphate and subsequent crystallization of uninterrupted pyramidal shaped crystals. The study, when applied, not only yields the well defined shape of pyramidal crystals but also produces a high purity form of salt crystals in comparison with naturally crystallized Fleur de Sel.

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The design of an industrial OSLO crystallizer is based on experiments in the lab, in asmall scale pilot plant, in a semi industrial plant and in an industrial plant that has been operating for 20 years. The objective was to produce spherical particle of salt with a size of about 5 mm; the known state of the art allowed only to produce particle size of about 2mm maximum. A development was made for 2 years in lab and small pilot scale; an industrial plant was started in 1987 This paper describes the main problems encountered at all stages of development and how they were solved: choice of the main operating parameters, validation on all the steps, resolution of hydrodynamics problems and practical controls of nucleation, control of scaling Most of the solutions adopted for production of large particle size of sodium chloride are also valid for other salts production and the OSLO technology can be applied for other salt production ; in some cases, very large particle size obtained can compete with usual crystallization + drying + size enlargement by compaction technology.

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In salt production from sea water, water is evaporated in open ponds and common salt （NaCl） is crystalized and harvested. At the end of sea salt production usually large quantities of high salinity brines, so-called bittern remains. Discharge of that bittern can lead to significant environmental challenges. Furthermore, but not less important, bittern contains a large amount of valuable minerals. To describe how to process sea bittern further to recover and extract these valuable minerals and convert them into precious by-products is the prime objective of this paper. The present work will focus on the production of potassium fertilizers and in particular potassium sulfate as an especially attractive by-product of seasalt production. The paper describes all essential process steps required to produce potassium sulfate （K₂SO₄） and potentially other valuable downstream products. Finally, some project examples and an economic assessment are given to underline, that processing of bittern is not only getting more and more important because society and companies are focused increasingly on environmental protection. In fact, it is shown that extracting valuable by-products out of bittern can be a very economically attractive option to diversify production and create additional input streams for sea salt works with a production capacity of above one million tons of common salt per year.

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In this study, we developed a simulation method for cation transport through cation-exchange membranes in an electrodialysis （ED） system containing 9 kinds of ions （Na^＋, K^＋, Mg^2＋, Ca^2＋, Sr^2＋, Cl^－, Br^－, HCO₃^－, SO₄2^－） by using ionic mobility derived from the modified Mackie and Meares’ theory. In order to confirm the validity of the simulation, we also conducted ED experiments using standard commercial IEMs. As a result, the measured values and the simulations agreed quantitatively with each other, even in the multi-component ion system. The simulation will help in the prediction of optimal ED operation conditions to reduce the running cost and/or to increase product purity.

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Regarding practical application of a reverse electrodialysis （RED） system using salinity gradient energy （SGE）, it would be appropriate to use seawater brine （BR） from a SWRO desalination plant instead of seawater （SW） due to high salinity. In this study, we have evaluated the power generation performance of a pilot-scale RED stack with a total effective membrane area of 180 m² using Model BR（90 mS/cm NaCl） and real river water （RW） as high and low salinity feed solutions, respectively. Model SW（50 mS/cm NaCl） was also used as a high salinity feed solution for comparison. The maximum gross power output of the RED stack increased with increasing current and then reached a maximum of 1.42 W/m²（256 W） and 0.93 W/m²（169 W） using BR and SW as the high salinity source with the energy conversion efficiency of about 15 ％ and 20 ％, respectively. The results indicate that a RED system using the stacks in this study generates 452 kW of gross power output using 60,000 m³/day of all discharged brine from the desalination center in Okinawa.

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In this study, we prepared poly （vinyl alcohol）（PVA）-based charged mosaic （CM） membrane from positively- and negatively-charged PVA-based block-copolymers by means of dispensing technique. The technique enables the fabrication of well-designed and tunable striped patterns by coating the two PVA-based polymers as anion- and cation-exchange domains. In addition, the main matrix of PVA allows a subsequent chemical crosslinking between the respective domains, resulting in good adhesion between the domains for easy handling. The prepared CM membranes had high permselectivity for electrolytes and the electrolyte flux depended not on the ratio of ion exchange capacity or the coating distance of the two charged domains but on the membrane potential.

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