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A simple but precise method for the PIXE analysis of trace heavy-metals in aqueous samples was developed, in which the PIXE targets were prepared by pre-concentrating heavy metals on a cellulose phosphate ion-exchange filter paper and no additional chemical treatment was required. Heavy metals in trace concentrations were quantitatively retained up to 16.7 μ-equivalent on a sheet of filter paper due to the excellent selectivity for heavy metals and ion-exchange kinetics of phosphate groups in cellulose matrix. Heavy metals of less than 1 μg on one filter paper are precisely and rapidly determined by PIXE analysis using 3-MeV proton beams. The present method is compared with the method preparing a PIXE target for each dissolved species of an element contained in aqueous samples. It will be resulted that the newly developed method enables an on-line PIXE analysis for river waters.

We report on the effect of 500 keV He${}^{+}$ ion implantation with a fluence of $3\times 10^{16}$ ions/cm² on Rb${}^{+}$-K${}^{+}$ ion exchanged KTiOPO₄ optical waveguide. The refractive index distribution after ion implantation, ion exchange, and ion implantation and subsequent ion exchange were reconstructed by reflectivity calculation method, inverse Wentzel–Kramers–Brillouin, and intensity calculation method, respectively. The near field intensity distribution of the waveguides was simulated by Beam Propagation Method. The phase analysis of the samples was measured by X-ray diffraction technique. The damage layer formed in the depth of maximum nuclear energy deposition by ion implantation acts as a barrier to block the ions diffusion into the sample. Results exhibit that ion implantation and subsequent ion exchange are effective means for optical waveguide formation.

Several ionic fullerene salts have been prepared based on a fulleropyrrolidine pyridinium cation and four different anions. The initial ionic fullerene can be easily prepared by quaternization of a pyridine-appended fulleropyrrolidine derivative in high yield. Anion exchange is a simple procedure giving several different salts of varying polarity. In addition to their characterization, the quantitative solubility of these salts has been studied in seven different solvents, including an imidazolium ionic liquid.

Layered double hydroxide (LDH) is a layered hydroxide and exchangeable anion is intercalated in its interlayer. Application of the LDH as a controlled-release material of interlayer anions has become of interest, thus it is important to clarify the elution behavior of interlayer anions. We synthesized hydrogenphosphate-intercalated Mg/Fe and Zn/Fe LDH and elution of phosphate from these LDH were tested in deionized water, sodium chloride solution, sodium sulfate solution, and sodium carbonate solution. For Mg/Fe LDH, the amount of eluted phosphate increased with time and reached to maximum that increased as higher concentrate solution was used. The elution of phosphate from Mg/Fe LDH could be described by the pseudo second-order equation. This elution behavior was explained as ion-exchange reaction of phosphate with sulfate or carbonate in tested solution by means of kinetic simulation using Runge-Kutta method. In the eluted solution, metal ions contained in the LDH were detected and its amount depended on pH of the tested solution, that is, amounts of eluted Mg and Zn ions were small at higher pH (ca. 10) for Mg/Fe and Zn/Fe LDH respectively, but large amount of Zn ion was detected when 2.03 mol·l^-1 carbonate solution (pH = 13) was used. Thus elution of phosphate was caused by two main reactions: ion exchange and decomposition of the LDH.

Zirconium phosphates (ZrP) with layered structure have been studied extensively over last 40 years because of their ion exchange, intercalation, and ion conductivity properties. The present paper reviews the preparation methods and exchange behavior of Zr(HPO₄)₂.H₂O, with special regards to its application in the development of antibacterial ceramics. The conductivity properties of ZrP salts are summarized and a new route to prepare commercial AgZr₂(PO₄)₃ antibacterial powders is reported.