Chemical characterization of airborne particulate matter in ambient air of Nagoya, Japan, as studied by the multielement determination with ICP-AES and ICP-MS.

The multielement determination of PM(10) (airborne particulate matter smaller than 10 microm) samples, which was collected by a high volume air sampler at the urban site of Nagoya City, was carried out by inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). The present analytical method was validated by analyzing urban particulate matter standard reference material of NIST SRM 1648. The analytical data for ca. 30 elements in PM(10) samples collected during a period from 8 September to 9 October, 2003, were obtained in the concentration range from sub-microg g(-1) to several-10 mg g(-1), but the data for 18 elements among ca. 30 elements were available for the characterization of PM(10) samples in ambient air, because of problems caused by the filter blanks. Then, the trends concerning the distributions of diverse elements in PM(10) samples were analyzed based on the enrichment factors and size distribution factors. The lithophile and siderophile elements were distributed more than 50% in coarse particle fraction (>2.1 microm), which was derived mainly from natural sources, such as soils and crustal minerals. On the other hand, chalcophile elements were distributed more than 50% in fine particle fraction (<2.1 microm), which was derived mostly from anthropogenic emission sources. The large enrichment of chalcophile elements in PM(10) samples as well as their mining influence factors (MIFs) suggested their wide use in industrial productions.     

Proton spin-lattice relaxation time in the α-VHx

The ¹H spin-lattice relaxation time T₁ has been measured in the α-VH_x. It is found that T₁ in the α-phase is essential ly determined by contact hyperfine interactions, and its variation with hydrogen concentration is in accord with a rigid-band model.     

Study of the fluorescence of perylene cation radical salts with a near field optical setup

A perylene-acetonitrile solution with TBAP (tetra-n-butylammonium perchlorate) electrocrystallizes on the electrode surface, under opportune conditions. It forms particular needle-like micro-crystals that have been studied recently for their peculiar electrical and optical properties and for the fundamental processes involved in the electron transfer responsible for the electrocrystallization. These intriguing structures present various fractal-like morphological organizations and diverse crystal shapes on the same deposition process. Up to now these formations have been studied optically by conventional standard microscopy. We introduce here a novel methodology to collect information on the actual orientation and crystal structure by a near field optical setup with originally fabricated probes. We performed, for the first time on these samples, near field fluorescence imaging showing evidence that the perylene aggregations actually have a distinct optical orientation.     

Tb3+-activated In2Si2O7 phosphor

Indium silicate activated by terbium was found to be an efficient phosphor with CR excitation, the luminosity of which was comparable to the most luminous of other terbium-activated silicates. For the preparation of this phosphor, alkaline earth metal flourides proved to act as a good mineralizer. The best result was obtained when a mixture of 1 mol In₂O₃, 2.2 mol SiO₂, 0.015 mol Tb₄O₇ and 0.05 mol BaF₂ was fired at 1 400°C in air for 4 h. Other rare earth luminescent centers such as Ce, Pr, Eu, Dy, Er and Tm were examined but none showed noticeable emission. Some UV excitation properties are also described.     

Hypothesis on the foundation of stochastic interpretations of quantum mechanics

The hypothesis that a particle exists in a cavity space in thermal equilibrium with photons and executes a Brownian motion is due to collisions with the photons leads to a realistic stochastic interpretation of quantum mechanics.     

Practical synthesis of chiral ligands for catalytic enantioselective cyanosilylation of ketones and ketoimines

A practical synthesis of chiral ligands that are useful for catalytic enantioselective cyanosilylation of ketones and ketoimines is described. Compared with the previous synthetic route, the number of total steps is decreased and the total yield is greatly improved. Furthermore, both (+)- and (-)-ligands are readily available by this new synthetic route.     

Confirmation of the structures of kuwanons G and H (albanins F and G) by partial synthesis

Conclusive evidence is presented supporting structures $\text{1}$ and $\text{2}$ for two natural Diels-Alder adducts isolated from mulberry and designated as kuwanon G (albanin F, moracenin B) and Kuwanon H (albanin G, Moracenin A).     

A method for ion-exchange separation of low levels of americium in environmental materials

A method is presented for separating low levels of americium from large environmental samples ( $ 200 l. of sea-water, $ 100 g of sediment, 500 g of biological material, etc.) by applying an anion-exchange process in methanolic acid medium.     

Synchronization of excitatory neurons with strongly heterogeneous phase responses

In many real-world oscillator systems, the phase response curves are highly heterogeneous. However, the dynamics of heterogeneous oscillator networks has not been seriously addressed. We propose a theoretical framework to analyze such a system by dealing explicitly with the heterogeneous phase response curves. We develop a method to solve the self-consistent equations for order parameters by using formal complex-valued phase variables, and apply our theory to networks of in vitro cortical neurons. We find a novel state transition that is not observed in previous oscillator network models.