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We analyzed 68 green and blue mussels collected from Cambodia, China, Hong Kong, India, Indonesia, Japan, Korea, Malaysia, Philippines, Vietnam and the USA during 2003 and 2007, to elucidate the occurrence and widespread distributions of emerging pollutants, synthetic musks and benzotriazole UV stabilizers (BUVSs) in Asia–Pacific coastal waters. Synthetic musks and BUVSs were detected in mussels from all countries, suggesting their ubiquitous contamination and widespread distribution. High concentrations of musks and BUVSs were detected in mussels from Japan and Korea, where the levels were comparable or greater than those of PCBs, DDTs and PBDEs. Significant correlations were found between the concentrations of HHCB and AHTN, and also between the concentrations of UV-327 and UV-328, which suggest similar sources and compositions of these compounds in commercial and industrial products. To our knowledge, this is the first study of large-scale monitoring of synthetic musks and BUVSs in Asia–Pacific coastal waters.

Low-temperature magnetic properties of the \ensuremath{\beta} and \ensuremath{\gamma} phases of p-nitrophenyl nitronyl nitroxide (p-NPNN) were determined by measuring the specific heat, the magnetic susceptibility, and the hysteresis curve of magnetization above $^{3}\mathrm{He}$ temperature in external magnetic fields. The \ensuremath{\beta}-phase crystal undergoes a bulk ferromagnetic transition at 0.60 K, which was confirmed by the magnetic entropy of ln2 due to one unpaired electron on the radical molecule and the hysteresis curve. The \ensuremath{\gamma} phase, on the other hand, revealed an antiferromagnetic transition at 0.65 K and one-dimensional ferromagnetic fluctuations above it. The specific-heat data of the \ensuremath{\gamma} phase in external fields were analyzed by a mean-field theory incorporated in the one-dimensional Heisenberg model. The details of sample characterization of each phase based on thermal analysis are also given.

A photoinduced memory effect in an electrophotographic receptor consisting of an iodine-doped conductive polymer electrode and a poly(N-vinylcarbazole) (PVK)/trinitrofluorenone (TNF) photoreceptor was investigated by means of xerographic, voltage-current and electrochemical measurements. The results showed that activation energy for memory formation was about 0.23 eV and was associated with the energy for CT-complex formation of PVK and iodine. This led us to propose a mechanism of memory formation in this system. Accordingly, it was indicated that the memory lifetime could be controlled by varying the kind of hole-transport material interacting with iodine.

Role of photo-generated space charges on the memory effect, observed in an iodine-doped conductive polymer / poly(N-vinylcarbazole) (PVK)-trinitrofluorenone (TNF) double-layered system, was investigated by means off voltage-current measurements. The results were consistent with the previous conclusion obtained by the xerographic technique. The memory effect was found to come from space charges formed at the electrode-photoreceptor interface containing iodine. The space charge formation induced apparent barrier height lowering against carrier injection and the magnitude of lowering was about 60 meV. It was also found that injected charges from polymer electrode per unit space charge was more than 2×103.

Using the zero-field muon-spin-relaxation technique, we have observed a long-range magnetic ordering of Cu moments in a tetragonal insulator $\mathrm{Ho}{\mathrm{Ba}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{x}$ with $x\ensuremath{\sim}6.2$. The magnitude of the internal field and its temperature dependence were found to be similar to those of Y${\mathrm{Ba}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{6.2}$. At temperatures below 3 K, freezing of the Ho magnetic moment was observed as in a 90-K superconductor Ho${\mathrm{Ba}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{6.9}$. These results imply that the effect of the magnetic rare-earth ${\mathrm{Ho}}^{3+}$ ions on the antiferromagnetism of the Cu ions is small, suggesting a relatively weak interaction between the Ho ions and the electrons in two-dimensional Cu-O planes.

Influences of the polymerization condition on properties of electrochemically synthesized polypyrrole film were studied with the aim of preparing high quality films for device application. Polymerization condition parameters such as the content of dissolved oxygen in the electrolytic solution, the polymerization temperature, the concentrations of monomer and supporting electrolyte, and others were varied, and the conductivity, the surface morphology, and adhesion to substrate of resulting films were examined. High quality films were synthesized as double-layered films consisting of a thin well adherent sublayer and a highly conductive thick overlayer. Optimizing various parameters, we could obtain high quality films with a satisfactorily flat surface, good adhesion to substrate, and a high conductivity (more than 300 S/cm).

An illumination memory previously observed in a polyaniline/polyvinylcarbazole double-layered photoconductor was studied in detail. Various parameters were examined, such as the corona condition, the light intensity, the wavelength, and the exposure energy. Ionized polyaniline molecules with a dopant anion were considered to be responsible for the memory effect. They were dissolved and diffused into the polyvinylcarbazole layer, and upon light absorption they induced photoconduction accompanied by the memory effect. The memory effect was found to be linear against the amount of surface charges dissipated by photons. By optimizing the parameters, a large memory contrast potential more than 500 V, which is suffciently high for most practical applications, was obtained.

A remarkable photo-induced illumination memory was observed in an iodine-doped conductive polymer/poly(N-vinylcarbazole) (PVK)-trinitrofluorenone (TNF) double-layered system. The memory was measured as a lowering of charge acceptance and investigated as a function of various parameters such as the wavelength, the intensity and the exposure of incident light. It was found that the interface between the conductive polymer containing iodine and the photoconductor is responsible for this phenomenon and the memory effect is caused by carriers generated in the photoconductor. The exposure needed for lowering the charge acceptance to half the initial value was about 30 µJ/cm2. The memory effect was also observed in an organic iodide-dispersed PVK/TNF system though its sensitivity was much lower than that of the aforementioned polymer-using system.