We report on observation of 4d ferromagnetic ordering in pure Pd fine particles. Results of our dc magnetic measurements as a function of Pd particle size show that the magnetization increases rapidly with decreasing particle size; a sample with 59 Å median radius at 1.8 K under 4 kOe shows a factor of nineteen larger magnetization than that of Pd bulk. We suggest that only the surface monolayers of Pd particles are magnetic. The ferromagnetic moment we deduced based on this assumption is 0.23 ± 0.19μB per atom which is comparable to the value predicted by the ab initio calculation.

GCP170, a member of the golgin family associated with the cytoplasmic face of the Golgi membrane, was found to have a Golgi localization signal at the NH 2 -terminal region (positions 137-237). Using this domain as bait in the yeast two-hybrid screening system, we identified a novel protein that interacted with GCP170. The 2.0-kilobase mRNA encoding a 137-amino acid protein of 16 kDa designated GCP16 was ubiquitously expressed. Immunofluorescence microscopy showed that GCP16 was co-localized with GCP170 and giantin in the Golgi region. Despite the absence of a hydrophobic domain sufficient for participating in membrane localization, GCP16 was found to be tightly associated with membranes like an integral membrane protein. 69 and Cys 72 , accounting for its tight association with the membrane. A mutant without potential acylation sites (C69A/C72A) was no longer localized to the Golgi, indicating that the acylation is prerequisite for the Golgi localization of GCP16. Although the mutant GCP16, even when overexpressed, had no effect on protein transport, overexpression of the wild type GCP16 caused an inhibitory effect on protein transport from the Golgi to the cell surface. Taken together, these results indicate that GCP16 is the acylated membrane protein, associated with GCP170, and possibly involved in vesicular transport from the Golgi to the cell surface. Labeling experiments with [ 3 H]palmitic acid and mutational analysis demonstrated that GCP16 was acylated at Cys

The origin of the magnetism of MnSi 1.7 nanoparticles in Si is investigated using the first-principles calculations: bulk and interface effects are considered. The bulk magnetic property is expected to be affected by stoichiometry, strain, and charge accumulation. Stoichiometry and charge accumulation induce a ferromagnetic state, and strain stabilizes the ferromagnetic state. Another factor, the MnSi 1.7 / Si interface formation, is seen as triggering ferromagnetism strongly localized at the interface. These two mechanisms are shown to be related to the experimentally determined hard and soft components, respectively.

The annealing-temperature (700–900 °C) dependence of the ferromagnetism of manganese-implanted silicon is investigated. In the annealed samples, the manganese-containing nanoparticles, whose mean size was found to get bigger with temperature, are formed and these samples show ferromagnetism. We obtain evidence that the samples annealed at 800–850 °C produce two kinds of ferromagnets and that one of them offers a coercivity as high as 2500 Oe, suggesting the possibility of Si-based nanostructures with stable ferromagnetism. The origin of these ferromagnetisms is also discussed in conjunction with the size distribution of the nanoparticles.

We investigated the magnetization of the ultrafine cadmium ferrite particles formed during the coprecipitation method and discussed the origin of enhanced magnetization based on the magnetic properties. A transmission electron microscopy micrograph shows aggregation of fine particles having two kinds of shapes, fibrous and granular. X-ray diffraction patterns of the specimens prepared by the coprecipitation method are composed of peaks corresponding to CdFe2O4, Cd(OH)2, and α-FeO(OH). The pattern indicates that the peaks of CdFe2O4 are fairly broad, suggesting the formation of a very small crystallite, with an average size of ∼8 nm. The ultrafine CdFe2O4 particles exhibit ferromagnetic behavior and have a net magnetization of 89±5 emu/g at 6 K. These results suggest that there must be many ferromagnetic clusters consisting of Fe3+ ions at the B sites around Fe3+ ions at the A site by the A–B interactions. Thus, such a change in the distribution of Fe3+ ions in the ultrafine CdFe2O4 particles results in increasing magnetization with decreasing particle size.

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: Hydrothermal systems related to magmatic intrusions in the Jozankei‐Zenibako district, southwest Hokkaido are examined, based on field observations, K‐Ar ages, and alteration mineral assemblages. The study reveals five major magmat–ic–hydrothermal systems of Late Miocene in age, comprising Ogawa (9. 7 Ma), Jozankei (9. 5–9. 0 Ma), Otarunaigawa (8. 7 Ma), Asarigawa (8. 8 and 6. 7 Ma) and Hariusu (6. 7 Ma). The Ogawa system is related to granodiorite, and the Jozankei, Otarunaigawa and Asarigawa systems are related to quartz porphyry. The Ogawa system includes potassic, sericitic, propylitic and advanced argillic alteration as well as base‐metal mineralization, represented by the Toyotomi deposit. The Jozankei and Otarunaigawa systems lack significant potassic alteration, and are accompanied by sericitic and propylitic alteration. The Otarunaigawa system is associated with base‐metal mineralization at Toyohiro and Inatoyo. The Asarigawa and Hariusu systems include advanced argillic and argillic alteration, as well as iron sulfide deposits. The presence of potassic alteration only in the Ogawa system is ascribed to deeper emplacement (˜3 km from the surface) of the intrusive magma. These systems formed in terrestrial environments that existed from ca. 11 Ma to 8. 5 Ma and after 7. 5 Ma in the district. Age–data compilation shows that the major advanced argillic alteration events in southwest Hokkaido, including those in the Jozankei‐Zenibako district, formed during the periods from 9. 7–6. 5 Ma and 3. 5–1. 5 Ma. These periods correspond to the timing of normal subduction of the Pacific plate beneath the Northeast Japan arc. Normal, in contrast to oblique, plate subduction is characterized by andesitic, polygenetic volcanism and associated advanced argillic alteration.

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