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Prompt determination of the positive or negative signs of charged objects promotes students’ understanding of electrostatics and motivates them to learn more about this field of physics. We developed a low-cost (about US$5) and easy-to-use device for checking the signs of the static charges in objects. It consists of two easy-to-build circuits, one for positive- and another for negative-charge detection. Both are composed of a metal–oxide–semiconductor field-effect transistor (MOSFET), an LED indicator, a tactile switch (momentary contact switch), and a jumper wire. In this paper, we provide instruction on how to build this device. Junior high school students who used it successfully created a triboelectric series by testing various daily-life materials. A free-response questionnaire revealed that the device is highly useful for consolidating students’ understanding of static electricity.

Continuous long-term monitoring is important for detecting ecological changes and understanding their causes, including anthropogenic impacts such as climate changes and eutrophication. Nonetheless, such long-term population studies have been rare, especially for sea urchins, which can affect community dynamics owing to their extensive herbivory and large population fluctuations. Here we present a long-term (from 1963 to 2014) dynamics of sea urchins in a fixed quadrat on a lower intertidal rocky flat in Hatakejima Island, southern Japan. We also conducted a complementary survey over the entire island approximately every five years from 1975 to 2013, and a 41-year assay for developmental abnormality of the sea urchin Heliocidaris crassispina using water adjacent to the island. The abundance of three commonest species in this area (H. crassispina, Echinostrephus molaris, and Echinometra spp.) and the richness of urchin species showed large variations, with high numbers in the 1960s and 1970s, followed by an abrupt decline in the late 1970s or early 1980s, and a gradual recovery subsequently. The species abundance and richness in the entire island survey showed good correlations with those in the quadrat census. Statistical analyses indicated that increasing water temperature and red tides were the major factors influencing the dynamics of abundance and species richness. Our studies reveal that anthropogenic environmental changes influence the long-term dynamics in abundance and richness of sea urchins.

Electron injection layers (EILs) based on a simple polymer blend of polyethyleneimine ethoxylated (PEIE) and poly[(9,9-bis(3'-(( N, N-dimethyl)- N-ethylammonium)-propyl)-2,7-fluorene)- alt-2,7-(9,9-dioctylfluorene)] (PFN-Br) can suppress the dependence of organic light-emitting device (OLED) performance on thickness variation compared with single PEIE or PFN-Br EILs. PEIE and PFN-Br were compatible with each other and PFN-Br uniformly mixed in the PEIE matrix. PFN-Br in PEIE formed more fluorene-fluorene pairs than PFN-Br alone. In addition, PEIE:PFN-Br blends reduced the work function (WF) substantially compared with single PEIE or PFN-Br polymer. PEIE:PFN-Br blends were applied to EILs in fluorescent polymer-based OLEDs. Optimized PEIE:PFN-Br blend EIL-based devices presented lower driving voltages and smaller dependences of device performance on EIL thickness than single PEIE or PFN-Br-based devices. These improvements were attributed to electron-transporting fluorene moieties, increased fluorene-fluorene pairs working as channels of electron transport, and the large WF reduction effect of PEIE:PFN-Br blends.

In a cooling malfunction accident of a high-level liquid waste (HLLW) tank, behavior of ruthenium (Ru) attracts much attention, since Ru could be oxidized to a volatile chemical form in the boiling and drying of HLLW, and part of radioactive Ru can potentially be released to the environment. In this study, nitrosyl Ru nitrate (Ru(NO)(NO3)3) dissolved in nitric acid (HNO3), which is commonly contained in a simulated HLLW, was dried and heated up to 723 K, and the evolved gas was introduced into a mass spectrometer. The well-known volatile species, ruthenium tetroxide (RuO4) was detected in a temperature range between 390 K and 500 K with the peak top around 440 K. Various gases such as HNO3, nitrogen dioxide (NO2), nitrogen monoxide (NO) also evolved due to evaporation of the nitric acid and decomposition of the nitrate ions. The ion current of RuO4 seems to increase with the increasing decomposition of nitrate, while the evaporation of HNO3 decreases. More volatilization of RuO4 was observed from the HNO3 solution containing not only Ru(NO)(NO3)3 but also cerium nitrate (Ce(NO3)3·6H2O) which was added for extra supply of nitrate ion, compared with that from the HNO3 solution containing only Ru(NO)(NO3)3. These experimental results suggest that Ru could be oxidized to form RuO4 by the nitrate ion as well as HNO3.

SUMMARY This paper proposes a method that obtains high-tone images from ultra-low-tone image by using spatial features. Areas are smoothed when the adjacent tone value of the area of interest is continuous, but areas are saved as edges when the adjacent tone value of the area of interest is discontinuous. Thus the area of interest can be classified into six patterns by area. Low-gradation images are changed into high-gradation images by processing with each pattern. Comparative experiments indicated that the proposed method was quantitatively and visually better than existing methods. The proposed method can change ultra-low-tone images into naturally high-gradation images.

We developed a chiral 1,1'-bi-2-naphthol-bridged imidazole dimer possessing 100 μs fast photochromism and high fatigue resistance. It offers great opportunities for the practical applications to fast photoresponsive chiral dopants, invisible security materials and optical trigger molecules to induce the dynamic structural changes in biological matters.

We evaluate dynamic molecular polarizability at near-resonance region using multiresolution multiwavelet (MRMW) basis set. The results obtained by traditional Gaussian basis sets are compared against the MRMW one. For perpendicular component, d-aug functions seem to be necessary. Very large Gaussian basis sets beyond d-aug-cc-pvqz can provide the results close to the complete space value obtained by the MRMW even for near-resonance region. Improvement by enlargement of Gaussian functions is less systematic in the parallel component than in the perpendicular component. The competitiveness of the MRMW method against Gaussian methods in the computational efficiency for property evaluation is also discussed. © 2012 Wiley Periodicals, Inc.

A [2.2]paracyclophane-bridged imidazole dimer having bulky 3′,4′,5′-triphenyl-1,1′:2′,1″-terphenyl substituents was synthesized and the photochromic properties were investigated. The half-life of the colored species generated by the UV irradiation of the parent imidazole dimer was 1.0 ms at 298 K in benzene. Although such bulky substituents are introduced on the imidazole dimer, the fast thermal back-reaction can be observed as found in other [2.2]paracyclophane-bridged imidazole dimers. Herein, enthalpy and entropy of the activation energies (∆H‡ and ∆S‡, respectively) for the thermal back-reaction of the present molecule were compared with other [2.2]paracyclophane-bridged imidazole dimers in order to investigate the generality and the limitation of the molecular design of the photochromic imidazole dimer along with the correlation between bulkiness of the substituents and the rate constant of the thermal back-reaction. Finally, we referred to a new method for controlling the rate constant of the thermal back-reaction of [2.2]paracyclophane-bridged imidazole dimers.

A lot of research, mostly using electron-injection layers (EILs) composed of alkali-metal compounds has been reported with a view to increase the efficiency of solution-processed organic light-emitting devices (OLEDs). However, these materials have intractable properties, such as a strong affinity for moisture, which cause the degradation of OLEDs. Consequently, optimal EIL materials should exhibit high electron-injection efficiency as well as be stable in air. In this study, polymer light-emitting devices (PLEDs) based on the commonly used yellow-fluorescence-emitting polymer F8BT, which utilize poly(diallyldimethylammonium)-based polymeric ionic liquids, are experimentally and analytically investigated. As a result, the optimized PLED employing an EIL comprising poly(diallyldimethylammonium) bis(trifluoromethanesulfonyl)imide (poly(DDA)TFSI), which is expected to display good moisture resistance because of water repellency of fluorocarbon groups, exhibits excellent storage stability in air and electroluminescence performance with a low turn-on voltage of 2.01 V, maximum external quantum efficiency of 9.00%, current efficiency of 30.1 cd A-1 , and power efficiency of 32.4 lm W-1 . The devices with poly(DDA)TFSI show one of the highest efficiencies as compared to the reported standard PLEDs. Moreover, poly(DDA)TFSI is applied as a hole-injection layer (HIL). The optimized PLED using poly(DDA)TFSI as the HIL exhibits performances comparable to those of a device that uses a conventional poly(3,4-ethylenedioxy-thiophene):poly(4-styrenesulfonate) HIL.

Since zirconium is considered an electrochemically active species under practical conditions of the electrorefining process, it is crucial to understand the electrochemical behavior of zirconium in LiCl–KCl melts containing actinide ions. In this study, the electrochemical codeposition of uranium and zirconium on a solid cathode was performed. It was found that the δ-(U, Zr) phase, which is the only intermediate phase of the uranium–zirconium binary alloy system, was deposited on a tantalum substrate by potentiostatic electrolysis at −1.60 V (vs. Ag + /Ag) in LiCl–KCl melts containing 0.13 in mol% UCl 3 and 0.23 in mol% ZrCl 4 at 773 K. To our knowledge, this is the first report on the electrochemical formation of the δ-(U, Zr) phase. The relative partial molar properties of uranium in the δ-(U, Zr) phase were evaluated by measuring the open-circuit-potentials of the electrochemically prepared δ-phase electrode.

In our previous study, a mixture of U and Pu was recovered in liquid Cd cathode from molten salt under various conditions of the U:Pu ratio. Two important things were observed. The first was that three kinds of precipitated phase had been detected in the saturated liquid Cd cathode, such as a U metal and two kinds of U-Pu-Cd compound. The compositions of the compounds were roughly (U+Pu):Cd = 1:11 and (U+Pu):Cd = 1:6. The second was that the U metal had selectively precipitated in the saturated liquid Cd cathode under the condition that the U:Pu ratio is higher than about 0.8 in the liquid Cd phase. In the present study, phase diagrams were evaluated by the CALPHAD method on the liquid Cd cathode containing U and Pu. The U-Pu-Cd compounds were modeled as MCd11-type and MCd6-type, respectively, based on the reported binary phase diagrams of U-Cd and Pu-Cd. The calculated result reasonably agreed with the experimental observations. The variations in the U and Pu activities were estimated along with the U:Pu...

Phylogeographic analyses were conducted for the dung beetle Phelotrupes laevistriatus (Motschulsky, 1857) (Coleoptera: Geotrupidae), which exhibits geographic variation in flight-muscle condition. Beetles with well-developed flight muscles, and thus capable of flying, are distributed in middle and southern Japan, from northern Honshu to Kyushu, whereas those without detectable flight muscle are distributed in northern Japan, on northern Honshu and Hokkaido. To investigate the origin of the flight-muscle dimorphism in P. laevistriatus, we determined sequences of a 603-bp fragment of the mitochondrial cytochrome oxidase subunit I (COI) gene for 258 individuals from 43 population samples. We constructed gene trees using the neighbor-joining method, maximum likelihood method, and maximum parsimony method and a haplotype network using the median-joining method. Six major clusters were recognized in each tree or network by these analyses. They occupied different ranges, being arranged from southwest to northeast as Clusters VI, V, IV, III, II, and I, with partial geographical overlaps between IV and III and between II and I. The beetles with well-developed muscles were included in all these clusters, whereas the beetles without detectable muscles were included in two northern clusters, i.e., Clusters I and II. The results suggest that the common ancestor of P. laevistriatus originally possessed flight ability and then diversified into regional clusters, after which the loss of flight muscles occurred in northern clusters, possibly in response to climatic conditions associated with increased latitude.

Our efforts to optimize prototype opioid receptor-like 1 (ORL1) antagonist 1 led to the discovery of 4-{3-[(2R)-2,3-dihydroxypropyl]-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl}-1-[(1S,3S,4R)-spiro[bicyclo[2.2.1]heptane-2,1′-cyclopropan]-3-ylmethyl]piperidine 10. 10 showed potent ORL1 antagonistic activity, excellent selectivity over other opioid receptors, and in vivo efficacy after oral dosing. Currently clinical trials of 10 are underway.

The synthesis and biological evaluation of new potent opioid receptor-like 1 (ORL1) antagonists are presented. Conversion of the thioether linkage of the prototype [It is reported prior to this communication as a consecutive series.: Kobayashi, K.; Kato, T.; Yamamoto, I.; Shimizu, A.; Mizutani, S.; Asai, M.; Kawamoto, H.; Ito, S.; Yoshizumi, T.; Hirayama, M.; Ozaki, S.; Ohta, H.; Okamoto, O. Bioorg. Med. Chem. Lett., in press] to the carbonyl linker effectively reduces susceptibility to P-glycoprotein (P-gp) efflux. This finding led to the identification of 2-cyclohexylcarbonylbenzimizole analogue 7c, which exhibited potent ORL1 activity, excellent selectivity over other receptors and ion channels, and poor susceptibility to P-gp. Compound 7c also showed satisfactory pharmacokinetic profiles and brain penetrability in laboratory animals. Furthermore, 7c showed good in vivo antagonism. Hence, 7c was selected as a clinical candidate for a brain-penetrable ORL1 antagonist.

A series of compounds based on 7-{[4-(2-methylphenyl)piperidin-1-yl]methyl}-6,7,8,9-tetrahydro-5 H-cyclohepta[ b]pyridine-9-ol ( (-)-8b), a potent and selective opioid receptor-like 1 (ORL1) antagonist, was prepared and evaluated using structure-activity relationship studies with the aim of removing its affinity to human ether-a-go-go related gene (hERG) K (+) channel. From these studies, 10l was identified as an optimized structure with respect to ORL1 antagonist activity, and affinity to the hERG K (+)channel. Furthermore, 10l showed good in vivo antagonism with a wide therapeutic index in regards to adverse cardiovascular effects.

A series of Nb40Ti30þxNi30� x alloys are characterized in terms of microstructure, crystal structure, ductility, susceptibility to hydrogen embrittlement, and hydrogen permeability as non-palladium-based hydrogen permeation alloys. The maximum hydrogen permeability and ductility of the alloy is exhibited by the alloy with composition of x ¼ 2 (Nb40Ti32Ni28). The enhancement of hydrogen permeability correlates well with an increase in the volume fraction of the primary (Nb, Ti) phase. After cold rolling and annealing, the hydrogen permeability of the Nb40Ti34Ni26 (x ¼ 4) alloy becomes superior to that of the Nb40Ti30Ni30 (x ¼ 0) composition previously reported to be the best in the Nb40Ti30þxNi30� x series. The present results indicate that the hydrogen permeability of the Nb-TiNi alloy can be optimized by annealing and appropriately adjusting the Ti/Ni ratio for a given niobium content. [doi:10.2320/matertrans.MA200851]

A cost-effective method with zero valent iron (ZVI) powder was developed for the purification of thiobencarb (TB)-contaminated water. The removal treatment was performed in the batch system. A sample solution of 10 ml containing 10 μg ml −1 of TB could be almost completely treated by 100 mg of ZVI at 25 °C for 12 h of treatment time. Since the formation of chloride ion in the aqueous solution during the treatment of TB was observed, the removal of TB with ZVI may contain two processes: reduction (degradation) and adsorption. Because the present treatment for TB is simple, easy handling and cheap, the developed technology with ZVI can contribute to the treatment of agricultural wastewaters.

Calcitonin gene-related peptide (CGRP) is thought to be a prominent neuropeptide in cardiovascular regulation and neuroimmune modulation. There are two isoforms of CGRP (αCGRP and βCGRP), and the main CGRP receptors are probably composed of a calcitonin receptor-like receptor (CLR) and a receptor activity-modifying protein (RAMP)1. However, the physiological functions of CGRP that are mediated through the CLR/RAMP1 receptors remain to be clarified. For an improved understanding of the functions, we generated mice deficient in RAMP1, a specific subunit of CGRP receptors, by a conditional gene-targeting technique. The RAMP1-deficient mice (RAMP1 −/− ) exhibited high blood pressure, with no changes in heart rate. αCGRP was found to have a potent vascular relaxant activity compared with βCGRP in the artery of the WT (RAMP1 +/+ ) mice. The activities of both CGRP isoforms were remarkably suppressed in the arteries of the RAMP1 −/− mice. The LPS-induced inflammatory responses of the RAMP1 −/− mice revealed a transient and significant increase in the serum CGRP levels and high serum levels of proinflammatory cytokines compared with the RAMP1 +/+ mice. αCGRP and βCGRP equally suppressed the production of TNF-α and IL-12 in bone marrow-derived dendritic cells stimulated with lipopolysaccharide. Their inhibitory effects were not observed in the bone marrow-derived dendritic cells of the RAMP1 −/− mice. These results indicate that CGRP signaling through CLR/RAMP1 receptors plays a crucial role in the regulation of both blood pressure by vascular relaxation and proinflammatory cytokine production from dendritic cells.

A simulated spent oxide fuel in a sintered pellet form, which contained the twelve elements U, Pu, Am, Np, Cm, Ce, Nd, Sm, Ba, Zr,Mo, and Pd, was reduced with Li metal in a molten LiCl bath at 923 K. More than 90% of U and Pu were reduced to metal to form a porous alloy without significant change in the Pu/U ratio. Small fractions of Pu were also combined with Pd to form stable alloys. In the gap of the porous U-Pu alloy, the aggregation of the rare-earth (RE) oxide was observed. Some amount of the RE elements and the actinoides leached from the pellet. The leaching ratio of Am to the initially loaded amount was only several percent, which was far from about 80% obtained in the previous ones on simple MOX including U, Pu, and Am. The difference suggests that a large part of Am existed in the RE oxide rather than in the U-Pu alloy. The detection of the RE elements and actinoides in the molten LiCl bath seemed to indicate that they dissolved into the molten LiCl bath containing the oxide ion, which is the by-product of the reduction, as solubility of RE elements was measured in the molten LiCl-Li2O previously.

Raman scattering measurements were performed for the first time on the ternary alkali nickel sulfide Rb2Ni3S4 single crystal, in which nickel ions form a Kagome lattice. Factor-group analyses were made to determine the zone center vibrational modes for the crystal structure of the Cs2Pt3S4-type with the space group of Fmmm, to which Rb2Ni3S4 belongs, and also for a unit stacked package layer with the point symmetry of 6/mmm piling up to the present layered sulfides. Raman active Ag(2) and Ag(1)+B2g modes were clearly observed as the subspecies modes which correlate to A1g and E2g of the stacked package. The Raman shift and line width of the observed modes, Ags and B2g, exhibited a monotonic temperature dependence in the range between 4 K and 390 K. These thermal properties were discussed in terms of cubic and quartic lattice anharmonicity. Furthermore, observed decreases in their scattering intensities with increasing temperature were discussed heuristically by taking account of the thermal enhancement of extrinsic carriers with activation energy, which was found to be commensurate with the magnitude obtained from a previous resistivity measurement.

A new species of the genus Sabellaria Lamarck, 1812 (Annelida: Polychaeta: Sabellariidae), is described from shallow water off Tottori, the Sea of Japan. Sabellaria tottoriensis n. sp., is gregarious with tubes constructed of sand and shell debris. The new species is distinguished by the character combination of 1 or 2 pairs of nuchal spines, two forms (long and short) of opercular paleae in the middle row, with the slender blades of long ones recurved outward. Detailed morphological features of the species are described and compared with other Japanese and worldwide congeners.

The process of preparing specimens of Rb 2 Ni 3 S 4 single crystals grown by the flux method was reconsidered to clarify the magnetic and electronic properties of this nickel sulfide. Specimens obtained by removing fluxes with water were confirmed to have a residual ferromagnetic moment, as previously reported by the present authors. Specimens peeled a surface of as-grown crystals off by taking advantage of the quadratic layer characteristic of this crystal were ascertained to be diamagnetic and to exhibit magnetic properties intrinsic to Rb 2 Ni 3 S 4 . However, the temperature dependence of the specific resistivity of the latter sample is similar to that of the former. Through examination of the experimental results, Rb 2 Ni 3 S 4 was identified as a nonmagnetic semiconductor in a low spin 3d 8 configuration of Ni 2+ .

Paranaitis Southern, 1914 (Phyllodocidae, Polychaeta) is revised based on an examination of all available types and newly collected specimens. Redescriptions are provided of the 11 previously described species considered valid: P. wahlbergi (Malmgren, 1865), P. abyssalis (Hartmann-Schroder, 1975), P. benthicola (Knox, 1960), P. bowersi (Benham, 1927), R caeca (Moore, 1903), R gardineri Perkins, 1984, P. inflata (Hutchings & Murray, 1984), R kosteriensis (Malmgren, 1867), P. polynoides (Moore, 1909), P. speciosa (Webster, 1879) and P. uschakovi Eibye-Jacobsen, 1991. Paranaitis misakiensis sp. nov., P. moritai sp. nov. and P. pumila sp. nov. are described from Japan. Anaitis peremptoria Claparede, 1870; Anaitis zeylanica Willey, 1905; Phyllooloce (Anaitis) papillosa Ehlers, 1887; and Phyllodoce (Anaitis) rubens Grube, 1880 are referred to as Phyllodocidae incertae sedis, and P. capensis (Day, 1960), P. formosa (Verrill, 1885) and R picta (Verrill, 1885) to as Paranaitis incertae sedis. Phyllodoce truncata (Hartmann-Schroder 1965) comb. nov. is removed from Paranaitis. Some previously unreported charaefers are introduced, including a series of proboscis characters, morphology of dorsal cirrophores, and symmetry of rostrum of chaetal shaft. Distinguishing characters for all recognized species of Paranaitis are provided in a table. In order to assess the position and delineation of Paranaitis and the relationships within this taxon, we present a morphology-based parsimony analysis of relationships within the Phyllodocidae. Paranaitis is shown to be paraphyletic at the exclusion of Chaetoparia, although current support does not allow for any formal synonymy. Phyllodoce and the Eteone-group appear as consecutive sister taxa to the Paranaitis-Chaetoparia clade. The monophyly of Notophyllinae is well supported, but low consensus resolution is obtained for the positions of major taxa such as Eulalia, Eumida, and the Mystides-group. (C) 2003 The Linnean Society of London.

Statins (HMG-CoA reductase inhibitors) have so-called pleiotropic effects, which directly reduce neoinitial inflammation of atherosclerosis, and one possible mechanism is the attenuation of oxidative stress. Although an increase in oxidant stress is suggested to cause and aggravate arteriosclerosis in diabetes, the origin of oxidant stress and effects of statins on the oxidant stress in diabetes are not clearly delineated. We evaluated in this study the effect of high glucose on superoxide anion (O_2^-) production in the J-774 macrophage-like cell line, and the effect of various statins (cerivastatin, fluvastatin, and nisvastatin) on it. The basal and 12-O-tetradecanoylphor-bol 13-acetate (TPA)-stimulated O_2^- productions were measured by chemiluminescence (CL) amplified with a Cypridina luciferin analog. Both basal CL and TPA-stimulated CL (TPA-CL) in J-774 cells cultured with high glucose were apparently increased in dose and time dependent manners, and the increments were clearly suppressed by a NADPH oxidase inhibitor (diphenyleneiodonium chloride) or a protein kinase C inhibitor (GF-109803 X). Three statins significantly inhibited the high glucose-induced excessive O_2^- production in a dose dependent manner. Furthermore, co-incubation with mevalonic acid and the metabolites, geranylgeranyl pyrophosphate and farnesyl pyrophosphate, partially prevented the statin-induced suppression of TPA-CL. These data suggest that in J-774 cells high glucose causes excessive O_2^- production through NADPH oxidase and protein kinase C pathways, and statins suppress the excessive O_2^- generation. This effect of statins could be, in part, dependent on the inhibition of synthesis of isoprenoid intermediates. Statins may be useful as a drug to prevent arteriosclerosis by inhibiting oxidative stress in poorly controlled diabetic patients.

The magnetic excitations from the gapped ground state in TlCuCl3 have been investigated by means of inelastic neutron scattering experiments. The excitation data were collected along four different directions in the a* – c* plane. A well-defined single magnetic excitation mode was observed. The lowest excitation occurs at Q=(h,0,l) with integer h and odd l, as observed in KCuCl3. The dispersion relations were analyzed by the cluster-series expansion up to the sixth order, so that the individual exchange interactions were evaluated. It was demonstrated that TlCuCl3 is a strongly coupled spin-dimer system.

The MOX pellet of approximately 10g was reduced with lithium metal in molten lithium chloride at 923K. The pellet has high density and consists of 90% of uranium, 10% of plutonium, and 0.2% of americium growing in from plutonium. No major fracturing of the pellet occurred during reaction. Uranium and plutonium were essentially completely reduced to metal with no significant change in the ratio between them. Most of the lithium oxide generated by the reaction dissolved in the molten salt. SEM observation clearly showed a lot of pores and cracks in the reacted pellet. The generation of the apertures was caused by significant decrease of molar volume from oxide to metal. Plutonium and americium were detected in the samples taken from the molten salt during the experiment. Approximately 5% of initial load of plutonium and 75% of americium eluded from the pellet and most of them precipitated on the bottom of the crucible in end of the experiment.

In order to clarify structural and magnetic phase transitions of a hexagonal triangular antiferromagnet TlFeCl 3 , dielectric and magnetic susceptibilities, D – E hysteresis loops and optical birefringence were measured. Successive structural phase transitions at 179 K( T 2 ), 83 K( T 3 ) and 79 K( T 4 ) were identified. At a range of temperatures T 4 < T < T 3 (phase IV), opened D – E loops were clearly observed. The dielectric behavior of the successive structural phase transitions of TlFeCl 3 were confirmed to be quite similar to those of KNiCl 3 and RbMnBr 3 which are Group I of KNiCl 3 -family crystals.

Notophyllum Orsted, 1843 (Phyllodocidae, Polychaeta) is revised based on all available types and a large number of newly collected specimens. Redescriptions are provided of the seven species considered valid: N. americanum Verrill, 1885, N. foliosum (Sars, 1835), N. imbricatum Moore, 1906, N. japonicum Marenzeller, 1879, N. multicirris (Grube, 1878), N. sagamianum Izuka, 1912 and N. splendens (Schmarda, 1861). Notophyllum imajimai sp. n. is described from Japan. Some previously unreported characters are introduced, including a series of proboscis characters, morphology of dorsal cirri and cirrophores, and first appearance of notoaciculae in non-cephalized segments. A parsimony analysis of these taxa is presented based on 20 morphological characters and indicates two well-supported clades: Notophyllum as traditionally delineated and (N. foliosum, N. americanum (N. imajimai sp. n., N. imbricatum)). Characters for distinguishing all species of Notophyllum are provided in a table. Previous identifications of ...

The process of preparing specimens of Rb 2 Ni 3 S 4 single crystals grown by the flux method was reconsidered to clarify the magnetic and electronic properties of this nickel sulfide. Specimens obtained by removing fluxes with water were confirmed to have a residual ferromagnetic moment, as previously reported by the present authors. Specimens peeled a surface of as-grown crystals off by taking advantage of the quadratic layer characteristic of this crystal were ascertained to be diamagnetic and to exhibit magnetic properties intrinsic to Rb 2 Ni 3 S 4 . However, the temperature dependence of the specific resistivity of the latter sample is similar to that of the former. Raman scattering measurement indicated that this system undergoes no structural phase transition. Magnetic measurements in Co-doped specimens were carried out to obtain further information on the host substance. The appropriate band structure of Rb 2 Ni 3 S 4 was calculated in terms of the full-potential linearized augmented plane-wave method in the local density approximation to understand the electronic properties of Rb 2 Ni 3 S 4 . Through examination of the experimental results and the obtained band structure, Rb 2 Ni 3 S 4 was identified as a non-magnetic semiconductor in a low spin 3d 8 configuration of Ni 2+ .

The complex phase transitions involving dielectricity and magnetism on distorted triangular lattice antiferromagnets, "KNiCl3-family" crystals, which have the crystal structures derived from the prototype CsNiCl3, were studied through the heat capacity measurements. These crystals are classified into characteristic three groups from the viewpoint of magnetic and structural properties clarified so far. The results of the dielectric constant measurement as a function of temperature are also presented in detail. The present calorimetric study reveaed that the structural successive phase transitions rather than the magnetic transitions in these crystals are recognized more distinctly as the presence of specific heat anomalies at the respective phase transition points.

Single-crystal X-ray and neutron diffraction study of the distorted-triangular-lattice antiferromagnet RbMnBr 3 was carried out in order to clarify the crystal structure below T 4 ∼222 K (phase V) and to find the origin of spin arrangement below T N =8.5 K. The phase-V diffraction pattern showed some systematic and accidental extinction of possible reflections with triple-domain formation. An orthorhombic structure of a space group symmetry P b c a with a unit cell \(2a_{0}\times\sqrt{3}a_{0}\times c_{0}\) ( Z =8) was proposed. The triangular lattice of Mn 2+ ions is distorted in a novel form, coined as a zigzag-row model. Spin arrangement of this model was deduced using the mean-field theory. Spin structures of RbMnBr 3 in the incommensurately modulated LT (low-field triangular) and the commensurately modulated HT (high-field triangular) phases are described.

Thermal conductivity measurements have been carried out for single crystals of the onedimensional (1D) antiferromagnetic (AF) Ising-like spin system ACoX3 (A = Rb, Cs; X = Cl, Br). A shoulder originating from the thermal conductivity due to spin excitations, \k{appa}?spin, has been observed around 60 K in the temperature dependence of the thermal conductivity along the c-axis parallel to spin chains for every ACoX3. To our knowledge, this is the first observation of ?\k{appa}spin in 1D AF Ising-like spin systems. It has been found that the magnitude of ?\k{appa}spin in ACoX3 is a little smaller than those in 1D AF Heisenberg spin systems. The reason is discussed in terms of the Heisenberg-like character in ACoX3., 14 pages, 3 figures, 1 table (in press). Journal of the Physical Society of Japan (2014)

Specific heat and Faraday rotation magnetometry were used to determine the axial magnetic phase diagram of the dilute hexagonal antiferromagnet Fe0.85Mg0.15Br2. In contrast to metamagnetic pure FeBr2, the first-order line of transverse phase transitions, H1(T), is disconnected with the antiferro-to-paramagnetic phase line Hc(T) and extends down to Ht = 0 at Tt ≈ 8.7 K. This is attributed to symmetric off-diagonal exchange in the presence of structural disorder. Moreover, a spin-flop phase emerges beyond Hc(T) up to a bicritical point (Tb ≈ 9.3 K, μ0Hb ≈ 1.3 T).