An improved method for the preparation of 1-alkyl-3-methylimidazolium hexafluorophosphates provides a series of room-temperature ionic liquids (RTILs) in which the 1-alkyl group is varied systematically from butyl to nonyl. For competitive solvent extraction of aqueous solutions of alkali metal chlorides with solutions of dicyclohexano-18-crown-6 (DC18C6) in these RTILs, the extraction efficiency generally diminished as the length of the 1-alkyl group was increased. Under the same conditions, extraction of alkali metal chlorides into solutions of DC18C6 in chloroform, nitrobenzene, and 1-octanol was undetectable. The extraction selectivity order for DC18C6 in the RTILs was K+ > Rb+ > Cs+ > Na+ > Li+. As the alkyl group in the RTIL was elongated, the K+/ Rb+ and K+/Cs+ selectivities exhibited general increases with the larger enhancement for the latter. For DC18C6 in 1-octyl-3-methylimidazolium hexafluorophosphate, the alkali metal cation extraction selectivity and efficiency were unaffected by variation of the aqueous-phase anion from chloride to nitrate to sulfate.

Here we describe the preparation of 25 beaded polystyrene-poly(ethylene glycol) graft copolymers from six spectroscopically active styrene monomers: styrene, 2,5-dimethylstyrene, 4-methylstyrene, 2,4-dimethylstyrene, 4-tert-butylstyrene, and 3-methylstyrene. These polymers were thoroughly characterized by Raman, infrared, and (1)H/(13)C NMR spectroscopies, and differential scanning calorimetry. Determination of the swelling properties, peptide synthesis, and on-bead streptavidin-alkaline phosphatase (SAP) binding assay further established that their physical and chemical properties where not significantly altered by the diversity of their encoded polystyrene core. Each of the 25 resins displayed a unique Raman and infrared vibrational fingerprint, which was converted into a "spectroscopic barcode". The position of each bar matches the peak wavenumber in the corresponding spectrum but is independent of its intensity. From this simplified representation similarity maps comparing 35 000 resin pairs were generated to establish the spectroscopic barcoding as a reliable encoding methodology. In effect, in 99% of the cases, the highest similarity coefficients were obtained for resin pairs prepared from the same styrene derivatives even after SAP binding assay. We have also shown that a small but unique combination of a resin's vibrations (30-40%) is sufficient for its identification. However, in rare cases where a resin's vibrational signature has been severely compromised, both the Raman and infrared barcodes were synergistically and reliably utilized to unequivocally identify its chemical make up.

To understand the collective properties of nanoparticles, it is necessary to control the particle size, spacing and ordering. Here we describe the chemical synthesis of well-controlled silver nanoparticles, the wet coat preparation and the optical properties of its film. The light incidence angle and polarization dependency of the resonant spectra show distinctive surface plasmon resonance extinction peaks for isolated particles and the coupled modes of neighbouring particles. Furthermore, we discuss the thermal treatment and dielectric surrounding effects on the optical properties of silver nanoparticle film.

This paper reports a continuous roll-to-roll printing of mesh patterns of silver oxide pastes on flexible polymer films and subsequent thermal treatment at 150 °C of the patterned pastes to convert to silver patterns. The pastes consist of silver(I) oxide particles, silver salt of tertiary fatty acid, AgOCO-C(CH 3 ) 2 -(CH 2 ) n -CH 3 and R-terpineol as the solvent. During the thermal process, nanosized silver particles were formed by the thermal reduction of silver oxide particles and the salt, followed by spontaneous condensation and further fusing, resulting in conductive silver films. The linear chain length n of silver salt, AgOCO-C(CH 3 ) 2 -(CH 2 ) n -CH 3 , in the pastes, affects the electrical conductivity of resulting silver films significantly. An optimal range of linear chain length is found as n ) 5-9. In the case of the paste with n ) 5, an optimal weight fraction range of the salt in the paste is found as 20-40 wt % if the solvent composition is held constant at 20 wt %. Using the paste with an optimal composition, we obtained high-performance electromagnetic wave interference (EMI) shielding films that have shown a comparable shielding effectiveness as that made of conventional sputtered metallic silver films.

This paper focuses on the reliability of gravure offset printing and presents a mechanism on how the width of the printed line increases on repeated printings. Of the various printing process parameters, such as the resting times between doctoring, off, and set, printing velocity, printing pressure, and so forth, we investigated the effects of printing velocity, printing pressure, and blanket’s thickness on the reliability of gravure offset printing. As the printing velocity increases, the reliability of gravure offset printing also increases. This is because the actual contact time between ink and blanket decreases, resulting in less solvent absorption into the blanket. Printing pressure does not have much influence on reliability. Even though some change was observed, it was within the range of experimental error. Under sufficient printing pressure, this observation implies that the more important factor as regards the absorption model is time rather than pressure. As the thickness of the blanket increases, the reliability also increases. In the case of a thin blanket, in particular, the reliability of gravure offset printing is sensitive to changes in thickness.