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A microelectrode is useful to determine electrochemical parameters such as diffusion coefficient, exchange current density, and Tafel slope without the limitations of ion diffusion. This study aims to develop a new microelectrode for use in high-temperature molten salts, which has been evaluated by determining the parameters of the Sm(III)/Sm(II) reaction in a LiCl–KCl eutectic molten salt. The electrochemical and kinetic properties of the samarium ion in the temperature range 723–823 K were calculated using the limiting current from cyclic voltammograms and the Allen–Hickling equation. The results imply that kinetic parameters (exchange current density and charge transfer coefficient) critical for designing pyroprocesses can be obtained using the developed microelectrode.

A diverse collection of 14 metal-organic frameworks (MOFs) is screened for C[O.sub.2] capture from flue gas by using a combined experimental and modeling approach. Molecular modeling has helped in the selection of adsorbents for C[O.sub.2] capture from flue gas by screening a large number of MOFs.

The application of the scattering-near-field scanning optical microscopy technique for the analysis of the polarization and dielectric function of molecules with higher order harmonics is determined. The third harmonic is shown to lead to the best lateral resolution, as well as dielectric constant in a porphyrin film.

Incorporation of an extended family of multi[(prophinato)zinc(II)](PZn)-based supermolecular fluorophores gives rise to a rich photophysical diversity in emissive polymersomes, enabling emission energy modulation over a broad spectra domain. Moreover, controlling polymer-to-flurophore non-covalent interactions finely tunes to bulk photophysical properties of theses soft, supermolecular, optical materials.

Using cyclic voltammetry and UV-vis absorption spectroscopic methods, we studied the precipitation reactions of trivalent uranium and lanthanides (Nd, Ce, and La)with the oxide ion in LiCl-KClmolten salts, which are likely side reactions during the electrorefining process for nuclear fuel treatment. The in situ electrochemical and spectroscopic monitoring demonstrated that U3+ consumed O2- with the mole ratio of 2:1, whereas the lanthanide ions reacted with O2- with the mole ratio of 1:1. Raman spectroscopy and X-ray diffraction were also employed to analyze the precipitates, confirming that U3+ was precipitated and oxidized into UO2, while the trivalent lanthanide ions formed oxychlorides (LnOCl). As a preliminary study of actinide co-precipitation, we also electrochemically monitored the precipitation reactions in a mixed melt containing uranium and lanthanides, demonstrating a higher reactivity of the former with the oxide ion in LiCl-KCl. [ABSTRACT FROM AUTHOR]

Although electroacoustic music has quickly flourished in spite of its relatively short history, the difficulties presented by its analysis have remained a pressing and lingering issue. From technical, social, cultural, and historical perspectives, we identify the analytical challenges of electroacoustic music: its rapid expansion/evolution, its novelties, contesting perceptual models, the dearth of socio-historical contextualization, and the lack of organizing/archiving efforts. As the critical field is suffering from a severe discontinuity between analytical projects, we draw connections amongst past studies as they relate to each of the aforementioned challenges. [ABSTRACT FROM AUTHOR]

High reversibility during crystallization leads to relatively defect-free crystals through repair of nonperiodic inclusions, including those derived from impurities. Microporous coordination polymers (MCPs) can achieve a high level of crystallinity through a related mechanism whereby coordination defects are repaired, leading to single crystals. In this work, we discovered and exploited the fact that this process is far from perfect for MCPs and that a minority ligand that is coordinatively identical to but distinct in shape from the majority linker can be inserted into the framework, resulting in defects. The reaction of Zn(II) with 1,4-benzenedicarboxylic acid (H2BDC) in the presence of small amounts of 1,3,5-tris(4-carboxyphenyl)benzene (H3BTB) leads to a new crystalline material, MOF-5(Oh), that is nearly identical to MOF-5 but has an octahedral morphology and a number of defect sites that are uniquely functionalized with dangling carboxylates. The reaction with Pd(OAc)2 impregnates the metal ions, creating a heterogeneous catalyst with ultrahigh surface area. The Pd(II)-catalyzed phenylation of naphthalene within Pd-impregnated MOF-5(Oh) demonstrates the potential utility of an MCP framework for modulating the reactivity and selectivity of such transformations. Furthermore, this novel synthetic approach can be applied to different MCPs and will provide scaffolds functionalized with catalytically active metal species. [ABSTRACT FROM AUTHOR]

In molecular electronics, the linker group, which attaches the functional molecular core to the electrode, plays a crucial role in determining the overall conductivity of the molecular junction. While much focus has been placed on optimizing molecular core conductivity, there have been relatively few attempts at designing optimal linker groups to metallic or semiconducting electrodes. The vast majority of molecular electronic studies use thiol linker groups; work probing alternative amine linker systems has only recently been explored. Here, we probe single–molecule conductances in phenylene–ethynylene molecules terminated with thiol and carbodithioate linkers, experimentally using STM break–junction methods and theoretically using a nonequilibrium Green's function approach. Experimental studies demonstrate that the carbodithioate linker augments electronic coupling to the metal electrode and lowers the effective barrier for charge transport relative to the conventional thiol linker, thus enhancing the conductance of the linker–phenylene–ethynylene–linker unit; these data underscore that phenylene–ethynylene–based structures are more highly conductive than originally appreciated in molecular electronics applications. The theoretical analysis shows that the nature of sulfur hybridization in these species is responsible for the order–of–magnitude increased conductance in carbodithioate–terminated systems relative to identical conjugated structures that feature classic thiol linkers, independent of the mechanism of charge transport. Interestingly, in these systems, the tunneling current is not dominated by the frontier molecular orbitals. While barriers

An interview with computer music pioneer Max V. Mathews is presented. According to Mathews, his provocation in writing Music I software happened after watching a concert where a pianist played Arnold Schoenberg with John Pierce, an inventor of communication satellites. He considers the sampling theorem as a means for making sounds using the computer. He mentions Jean-Claude Risset and John Chowning as two people who worked wonders with computers in the creation of beautiful sound.

Carbodithioate-terminated bis(phenylene)ethynylenes and oligo(phenyleneethynylene)s have been synthesized from TMSE-protected 4-iododithiobenzoic acid ester (1) and 4-ethynyldithiobenzoic acid ester (3) via Pd-catalyzed cross-coupling reactions. TEM and spectroscopic studies demonstrate that the reaction of 4-(phenylethynyl)dithiobenzoate with alkylamine-protected gold nanoparticles (AuNPs) produces the corresponding organocarbodithioate-functionalized AuNPs. [ABSTRACT FROM AUTHOR]

The article reviews the music release "Alphabet Book," by Paul Lansky.

The article reviews the exhibition "Toronto Electroacoustic Symposium," held at Toronto, Ontario from August 7 to 9, 2008.

The article presents a series of articles published within the issue about computer music pioneer Max V. Mathews, including John Chowning's narration of his journey with Mathews from San Francisco Bay to Hilo, Hawaii in 1989, an interview which provided access to Mathews' complete collection of publications, personal letters and photographs and some articles written by colleagues like Jon Appleton and Hubert Howe.

The article discusses the use of a combined experimental and modeling approach to screen metal-organic frameworks (MOFs) for carbon dioxide (CO2) capture derived from flue gas in line with the continuous attempt of greenhouse gas mitigation. It highlights the significance of understanding MOFs in the fundamentals of developing MOF-based processes and discusses the methods of molecular modeling strategy for (CO2). The advantage of molecular approach is also mentioned.