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We show theoretically and experimentally that accurate transport measurements are possible even within the short time provided by pulsed magnetic fields. For this purpose, a new method has been devised, which removes the noise component of a specific frequency from the signal by taking a linear combination of the results of numerical phase detection using multiple integer periods. We also established a method to unambiguously determine the phase rotation angle in AC transport measurements using a frequency range of tens of kilohertz. We revealed that the dominant noise in low-frequency transport measurements in pulsed magnetic fields is the electromagnetic induction caused by mechanical vibrations of wire loops in inhomogeneous magnetic fields. These results strongly suggest that accurate transport measurements in short-pulsed magnets are possible when mechanical vibrations are well suppressed.

We investigated the magnetic properties of the Ru-doped MnNiGe system. The temperature dependence of magnetization, M ( T ) , of Mn0.8Ru0.2NiGe shows a step-like anomaly at around T t = 173 K (heating process) with a hysteresis of 9 K between the cooling and heating processes. The Mn0.8Ru0.2NiGe compound exhibits a first-order martensite structural change coupled with the ferromagnetic (FM) transition, as seen in the MnNiGe–CoNiGe system. T t increases linearly with increasing the magnetic field B . The T dependence of the isothermal magnetic entropy change, Δ S M ( T ) , peaks at around T t , with values of − 4 . 7 , − 15 . 1 , − 24 . 4 , and − 32 . 1 J ⋅ kg − 1 ⋅ K−1 for Δ B = 1 , 3, 5, and 7 T, respectively. The three refrigerant capacities estimated from the Δ S M ( T ) curve show a linear dependence on Δ B . The calculated density of states, DOS, of Mn0.75Ru0.25NiGe in the paramagnetic-hexagonal austenite phase shows a peak at the Fermi energy, E F , and the Mn 3 d orbitals contribute significantly to this peak. On the other hand, the DOS at the E F for the compound in the ferromagnetic-orthorhombic martensite phase is smaller than that of the compound in the austenite phase. As the total energy of the electron system, E e , decreases with the structural change, the phase transition of this system at T t is driven by the band-Jahn–Teller effect, where the Mn 3 d orbitals play the main role.

We demonstrate that the cluster-glass state emerges as ferromagnetic quantum criticality is avoided in the itinerant ferromagnet ${\mathrm{Sr}}_{1\ensuremath{-}x}{({\mathrm{La}}_{0.5}{\mathrm{K}}_{0.5})}_{x}{\mathrm{RuO}}_{3}$. In this compound, the ferromagnetic order is suppressed by increasing $x$ and then disappears at the critical concentration: $x=0.5$. In this $x$ range, the present study reveals that no prominent feature is ascribed to the quantum critical fluctuations in specific heat. Instead, ac magnetic susceptibility exhibits a broad peak due to spontaneous spin freezing, and the peak temperature depends significantly on the frequency of the applied ac magnetic field. Furthermore, specific heat is enhanced within a wide temperature range, whereas specific heat shows no salient anomaly associated with spin freezing. These features are characteristics of the formation of cluster glass; in particular, the observed frequency variations in ac magnetic susceptibility are well described by the Vogel-Fulcher law. We compare the features concerning the suppression of the ferromagnetic order in this doped compound with those in isostructural Ca- and La-doped ${\mathrm{SrRuO}}_{3}$ and suggest that a local correlated disorder effect and the very small coherence of itinerant Ru $4d$ electrons are responsible for the cluster-glass formation instead of the quantum phase transition in ${\mathrm{Sr}}_{1\ensuremath{-}x}{({\mathrm{La}}_{0.5}{\mathrm{K}}_{0.5})}_{x}{\mathrm{RuO}}_{3}$.

We have developed a new calorimeter for measuring thermodynamic properties in pulsed magnetic fields. An instrumental design is described along with the construction details including the sensitivity of a RuO2 thermometer. The operation of the calorimeter is demonstrated by measuring heat capacity of three samples, pure Germanium, CeCu2Ge2, and $\kappa$-(BEDT-TTF)2Cu[N(CN)2]Br, in pulsed fields up to 43.5 T. We have found that realization of field-stability is a key for measuring high-resolution heat capacity under pulsed fields. We have also tested the performance of the calorimeter by employing two measurement techniques; the quasi-adiabatic and dual-slope methods. We demonstrate that the calorimeter developed in this study is capable of performing high-resolution calorimetry in pulsed magnetic fields, which opens new opportunities for high-field thermodynamic studies., Comment: 17 pages, 7 figures

We investigated the magnetic properties of the ilmenite-type manganates $\mathrm{MgMn}{\mathrm{O}}_{3}$ and $\mathrm{ZnMn}{\mathrm{O}}_{3}$, both of which are composed of a honeycomb lattice of magnetic $\mathrm{M}{\mathrm{n}}^{4+}$ ions. Both compounds show antiferromagnetic order with weak ferromagnetic moments. In particular, $\mathrm{MgMn}{\mathrm{O}}_{3}$ exhibits a magnetization ``reversal'' behavior which can be described by the $N$-type ferrimagnetism in the N\'eel's classification. The relationship between the magnetic properties and the crystal and magnetic structures probed by the neutron diffraction experiments indicates that the two honeycomb lattice magnets have different ${J}_{1}\ensuremath{-}{J}_{2}$ parameter sets, placing them in the distinct regions in the phase diagram; both nearest neighbor (NN) and next nearest neighbor (NNN) exchange interactions are antiferromagnetic in $\mathrm{MgMn}{\mathrm{O}}_{3}$, while NN and NNN interactions become ferromagnetic and antiferromagnet, respectively, in $\mathrm{ZnMn}{\mathrm{O}}_{3}$.

Single crystals are indispensable for understanding the fundamental properties of materials, although obtaining them are often challenging. To investigate the magnetic properties of a kagome-lattice antiferromagnet, we have performed a topochemical crystal transformation from a copper mineral volborthite with a distorted kagome lattice into another copper mineral vesignieite with an almost perfect kagome lattice. A millimeter-sized crystal of vesignieite, which is difficult to prepare via direct chemical reactions, has been successfully obtained. Magnetization measurements on the crystals reveal a unique magnetic order with weak-ferromagnetic moments lying within the kagome plane and successive anomalies in the magnetization curve, which would give important information on the magnetic order of the kagome-lattice antiferromagnet. The present results demonstrate a novel route via the topochemical crystal transformation in preparing a hard-to-obtain crystal.

We have investigated the crystal structure and magnetic properties of the synthetic copper mineral engelhauptite, $\mathrm{KC}{\mathrm{u}}_{3}{\mathrm{V}}_{2}{\mathrm{O}}_{7}{(\mathrm{OH})}_{2}\mathrm{Cl}$, which possesses a kagome lattice made of $\mathrm{C}{\mathrm{u}}^{2+}$ ($3{d}^{9}$) ions. Unlike the hexagonal structure with a perfect kagome lattice reported in the natural mineral, a synthetic crystal has a monoclinic structure with a distorted kagome lattice. We observe a magnetic transition at 6 K and an anomaly in the magnetization curve around 50 T. Engelhauptite represents a variant of the $S=1/2$ kagome antiferromagnet and we discuss the structure-property relationship by comparing engelhauptite and its relative compound volborthite, $\mathrm{C}{\mathrm{u}}_{3}{\mathrm{V}}_{2}{\mathrm{O}}_{7}{(\mathrm{OH})}_{2}\ifmmode\cdot\else\textperiodcentered\fi{}2{\mathrm{H}}_{2}\mathrm{O}$.

Magnetic and structural properties of double perovskite type bromides Cs2 MBr6 (M = Ta, Nb), where Ta4+ (5d 1) and Nb4+ (4d 1) ions form the face centered cubic lattice, are investigated and compared with chlorides Cs2 MCl6. Cs2TaBr6 exhibits the effective magnetic moment of 0.24 μ B, which is much smaller than the spin only value of a d 1 ion, 1.73 μ B, and comparable to 0.25 μ B in Cs2TaCl6. On the other hand, the effective magnetic moment of Cs2NbBr6 is 0.7 μ B and is substantially smaller than 1.0 μ B in Cs2NbCl6. On cooling, successive structural and magnetic phase transitions accompanying the release of electronic entropy approximately Rln 4 in total as expected for the J eff = 3/2 state are observed. The type of the ligand changes the temperature dependence of magnetic susceptibility at low temperature as well as its magnitude. The role of the ligands on the magnetism of J eff = 3/2 Mott insulators are discussed in the light of metal–ligand hybridization and the electron–lattice coupling.

An osmium chloride with the chemical formula of OsxCl3 (x = 0.81) was synthesized and its crystal structure and thermodynamic properties were investigated. OsxCl3 crystallizes in a layered CdCl2-type structure with the triangular lattice partially occupied by Os ions on average. However, on microscopic length scales, the triangular lattice is composed of nano-domains with a honeycomb arrangement of Os ions, as observed by electron microscopy and Raman scattering experiments. Magnetization and heat capacity measurements revealed an absence of magnetic long-range order down to 0.08 K, while a broad peak in heat capacity at 0.15 K may indicate a short-range order in the local honeycomb lattice. OsxCl3 may exhibit certain aspects of the Kitaev spin liquid that are expected for a perfect honeycomb lattice of osmium trichloride., Comment: 11 pages, 8 figures

One of the authors developed the high strength and high conductivity Cu-24 wt% Ag alloy as a conductor material for high field magnets twenty years ago.Wire and sheet of the alloy have been used as a conductor material for pulsed magnets or resistive magnets of the high magnetic field facilities of each country. However, the alloy required large quantities of Ag addition to achieve high strength. The cost performance and workability of the alloy were not good for that. So, we investigated possibility of low Cu-Ag alloy for decreasing in material cost and improving in workability. We succeeded in the development of the Cu-6 wt% Ag alloy by the new heat treatment which is superior to the characteristic of the Cu-24 wt% Ag alloy even if the amount of Ag content is decreased in 1/4. At present, we make a lot of high field pulsed magnets by using the Cu-6 wt% Ag wire manufactured industrially, and do that magnetic field experiment and are getting good results at the ISSP, the university of Tokyo. We will talk about the characteristic, new heat treatment method and the manufacturing process of the conductor material for the Cu-6 wt% Ag alloy.

We perform a combined experimental and theoretical study of a magnetic-field ($B$) induced evolution of magnetic and ferroelectric properties in an antiferromagnetic material Pb(TiO)Cu$_4$(PO$_4$)$_4$, whose structure is characterized by a staggered array of Cu$_4$O$_{12}$ magnetic units with convex geometry known as square cupola. Our experiments show a $B$-induced phase transition from a previously reported low-$B$ linear magnetoelectric phase to a new high-$B$ magnetoelectric phase, which accompanies a 90$^\circ$ flop of electric polarization and gigantic magnetodielectric effect. Moreover, we observe a $B$-induced sign reversal of ferroelectric polarization in the high-$B$ phase. Our model and first-principles calculations reveal that the observed complex magnetoelectric behavior is well explained in terms of a $B$-dependent electric polarization generated in each Cu$_4$O$_{12}$ unit by the so-called exchange striction mechanism. The present study demonstrates that the materials design based on the magnetic structural unit with convex geometry deserves to be explored for developing strong magnetoelectric couplings., 13 pages, 9 figures

We have successfully synthesized the novel antiferromagnets with Ir$^{4+}$ honeycomb lattice ZnIrO$_3$ and MgIrO$_3$ and investigated their magnetic and thermodynamic properties. The two iridates are isomorphic but exhibit qualitatively different magnetic properties. ZnIrO$_3$ shows antiferromagnetic ordering below 46.6 K, whereas MgIrO$_3$ displays weak ferromagnetic behavior below 31.8 K owing to formation of a canted antiferromagnetic ordering. The measurement of magnetic susceptibility with using an oriented powder sample revealed the presence of an XY-like magnetic anisotropy and a tilting magnetic structure which is possibly stabilized by the Kitaev interaction. Moreover, magnetization curves of MgIrO3 and ZnIrO3 up to 60 T show different behaviors, demonstrating that each magnetic ground state is different with each other. We discuss the difference in the ground state between MgIrO$_3$ and ZnIrO$_3$ from the viewpoint a magnetic model consisting of the Kitaev and Dzyaloshinskii-Moriya interactions with the spin frustration effect on the honeycomb lattice.

We report a comprehensive study on the magnetic and structural properties of the spinel sulfides LiInCr4S8, LiGaCr4S8, and CuInCr4S8, where Li^+/Cu^+ and Ga^3+/In^3+ ions form a zinc-blende-type order. On the basis of synchrotron X-ray diffraction and magnetization data obtained using polycrystalline samples, these three sulfides are suggested to be breathing pyrochlore magnets with alternating antiferromagnetic and ferromagnetic interactions on the small and large tetrahedra, respectively. The measured magnetization processes of the three sulfides up to 72 T are significantly different. The magnetization curves of LiInCr4S8 and CuInCr4S8 have large hysteresis loops with different shapes, while there is no hysteresis in that of LiGaCr4S8. Geometrical frustration of the small tetrahedron is likely to give rise to a wide variety of ground states, indicating the rich physics in these antiferromagnetic–ferromagnetic breathing pyrochlore magnets., ファイル公開：2019/03/15

We here report magnetostriction measurements under pulsed megagauss fields using a high-speed 100 MHz strain monitoring system devised using fiber Bragg grating (FBG) technique with optical filter method. The optical filter method is a detection scheme of the strain of FBG, where the changing Bragg wavelength of the FBG reflection is converted to the intensity of reflected light to enable the 100 MHz measurement. In order to show the usefulness and reliability of the method, we report the measurements for solid oxygen, spin-controlled crystal, and volborthite, a deformed Kagom\'{e} quantum spin lattice, using static magnetic fields up to 7 T and non-destructive millisecond pulse magnets up to 50 T. Then, we show the application of the method for the magnetostriction measurements of CaV$_{4}$O$_{9}$, a two-dimensional antiferromagnet with spin-halves, and LaCoO$_{3}$, an anomalous spin-crossover oxide, in the megagauss fields., Comment: 9pages, 6 figures, Conference proceedings for MegaGauss16 at Kashiwa, Japan in Sept. 2018

Alkali superoxide CsO2 is one of candidates for the spin-1/2 one-dimensional (1D) antiferromagnet, which may be sequentially caused by an ordering of the pi-orbital of O2- molecule below TS ~ 70 K. Here, we report on the magnetism in powder CsO2 and high-magnetic field magnetization measurements in pulsed-magnetic fields of up to 60 T. We obtained the low temperature phase diagram around the antiferromagnetic ordering temperature TN = 9.6 K under the magnetic field. At 1.3 K, remarkable up-turn curvature in the magnetization around a saturation field of ~ 60 T is found, which corresponds to the spin-1/2. We will compare it with the theoretical calculation., Comment: 11 pages, 3 figures

An apparatus, which scans temperature in sub-seconds for measuring the temperature dependence of the resistivity, is proposed. This apparatus contains a thermal bath and a sample platform on which a thin-film thermometer and a thin-film heater are sputtered. By thermally isolating the sample platform from surrounding parts, the sample temperature can be scanned at a high sweep rate of 200-300K/s. As a demonstration of the apparatus, the resistivity of a niobium-titanium alloy is measured in a pulsed magnetic field. In addition, as another application of the apparatus, the dielectric polarization measurement of the quantum-paraelectric material SrTiO3 is described.

The ThCr2Si2-type layered compound SrCo2P2 shows an itinerant-electron metamagnetic transition at high magnetic field. To investigate substitution effects on the itinerant metamagnetic transition, we synthesized Sr[1-x]LaxCo2P2 and SrCo2(P[1-x]Gex)2 and measured their magnetic properties, including magnetizations under pulsed high magnetic fields. We have revealed a strong x dependence of the metamagnetic transition which is consistent with the band theory describing the physical properties in metals., 20th International Conference on Magnetism, ICM 2015

The authors have studied the multiferroic properties of a triangular lattice magnet with ferromagnetic nearest-neighbor (NN) interactions, using single-crystal $\ensuremath{\alpha}$-NaFeO${}_{2}$ grown by hydrothermal synthesis. Despite the ferromagnetic NN interactions, this system exhibits very rich magnetoelectric phase diagrams induced by application of magnetic field. The relationship between complex magnetic ordering and ferroelectric polarization can be explained by the inverse Dzyaloshinskii-Moriya effect. Competition between antiferromagnetic second NN interactions in the triangular lattice plane and weak inter-plane interactions leads to a rich phase diagram for the crystal under study.

The magnetization processes of the spin-3/2 antiferromagnet ${\mathrm{LiInCr}}_{4}{\mathrm{O}}_{8}$ comprising a ``breathing'' pyrochlore lattice, which is an alternating array of small and large tetrahedra, are studied under ultrahigh magnetic fields of up to 130 T using state-of-the-art pulsed magnets. A half magnetization plateau is observed above 90 T to 130 T, suggesting that ${\mathrm{LiInCr}}_{4}{\mathrm{O}}_{8}$ has a strong spin-lattice coupling, similar to conventional chromium spinel oxides. The magnetization of ${\mathrm{LiGa}}_{0.125}{\mathrm{In}}_{0.875}{\mathrm{Cr}}_{4}{\mathrm{O}}_{8}$, in which the structural and magnetic transitions at low temperatures have been completely suppressed, shows a sudden increase above 13 T, indicating that a spin gap of 2.2 meV exists between a tetramer singlet ground state and an excited state with total spin 1, with the latter being stabilized by the application of a magnetic field. The breathing pyrochlore antiferromagnet is found to be a unique frustrated system with strong spin-lattice coupling and bond alternation.

We have succeeded in synthesizing a new organic biradical F4BIPBNN [= 2,2′-(3,3′,5,5′-tetrafluorobiphenyl-4,4′-diyl)bis(4,4,5,5-tetramethylimidazolin-1-oxyl 3-oxide)] which forms an S = 1=2 Heisenberg three-dimensional honeycomb antiferromagnet. Each site of a honeycomb layer alternately couples with upper or lower layers, which results in the unique three-dimensional honeycomb network with four nearest neighbors. At zero magnetic field, antiferromagnetic long-range order has been observed below TN = 2.7 K. Magnetic susceptibility in both paramagnetic and antiferromagnetic states and the magnetization curves are well reproduced by quantum Monte Carlo calculations with three antiferromagnetic interactions in the range of 4.3 to 6.6 K. From the concave shape of the magnetization curve, the shrinkage of spin due to spin fluctuations is evaluated to approximately 30% with respect to its classical value. The phase diagram of magnetic field versus temperature was determined by heat capacity and magnetization. In the field region below 3 T, a slight increase of TN was observed, which reflects the effect of spin fluctuations., Dr. A. Arauzo from General Services for Research of University of Zaragoza is acknowledged. JC and FP acknowledge grant number MAT2015-68200-C2-2-P. This work was partly supported by JSPS KAKENHI Grant Number JP15H03695 for YH. This work was performed in part under the Inter-University Cooperative Research Program of the Institute for Materials Research, Tohoku University, and in Institute for Molecular Science, supported by Nanotechnology Platform Program (Molecule and Material Synthesis) of the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan.

A new experiment to measure vacuum magnetic birefringence (VMB), the OVAL experiment, is reported. We developed an original pulsed magnet that has a high repetition rate and applies the strongest magnetic field among VMB experiments. The vibration isolation design and feedback system enable the direct combination of the magnet with a Fabry-P\'erot cavity. To ensure the searching potential, a calibration measurement with dilute nitrogen gas and a prototype search for vacuum magnetic birefringence are performed. Based on the results, a strategy to observe vacuum magnetic birefringence is reported., Comment: 9 pages, 11 figures

We successfully synthesized the verdazyl-based salt (o-MePy-V)(TCNQ) [o-MePy-V = 3-(2-methylpyridyl)-1,5-diphenylverdazyl; TCNQ = 7,7,8,8-tetracyanoquinodimethane]. Ab initio molecular orbital calc...

We investigated the magnetism of FeVMoO7 by performing magnetization, specific heat, electron spin resonance, and neutron diffraction experiments. We observed an antiferromagnetically ordered state...

As novel tools to study magnetic shape memory alloys, a high-speed optical microscope system and a measurement system of magnetocaloric effects (MCEs) in pulsed magnetic fields are developed. Using the high-speed imaging system, successive changes in the surface morphology are visualized in the process of magnetic field-induced reverse martensitic transformation in Ni 45 Co 5 Mn 36.7 In 13.3 . The MCEs of Gd studied in pulsed fields show reasonable agreement with the earlier results obtained in steady fields. Application of high magnetic fields up to 55 T realizes a gigantic adiabatic heating of 63 K.

The magnetic properties of K2Mn3(OH)2(VO4)2 are investigated up to a very high magnetic field of over 200 T. In this material, Mn atoms form a two-dimensional multi-kagome-strip (MKS) lattice, whic...

Orthorombic Cu5(PO4)3(OH)4 (pseudomalachite) is a layered compound. Each Cu-O layer in this compound is separated by PO4 tetrahedra. The spin network in the bc-plane of a pseudomlachite is composed of triangles and pentagons, which will induce the spin frustration effect. This network may be a new type of geometrically frustrated spin lattice. Magnetic susceptibility, specific heat, high field magnetization measurements are used to study the magnetic properties of Cu5(PO4)3(OH)4 in natural mineral samples. Magnetic ordering is observed at around 4.2 K. The spin entropy change at the transition temperature is about one-fifth times smaller than that expected for a usual long-range order. A 1/5 magnetization plateau is observed in the high-field magnetization curve. The plateau is explained based on a simple model in which the spin network is assumed to be composed of chain, dimer and monomer units.

We have developed SDX, aluminum foil with a conductive carbon layer, to reduce cell resistance. SDX also showed high rate performances. To reveal that mechanism, we prepared aluminum foil with various chemical forming layers for studying of resistance and compared to two famous theories about conductive mechanism of carbon particles and aluminum foil.

Optical absorption spectra of solid oxygen α phase and liquid oxygen were measured in high magnetic fields over 100 T using a single turn coil method. The absorption originates from the bimolecular transition was observed. The spectra strongly reflect the local magnetic interaction between two oxygen molecules. The shape of the absorption spectrum of the α oxygen changed dramatically with increasing magnetic fields, even though the absorption intensity of liquid oxygen simply declined. This difference cannot be explained by only the local magnetic interaction, and we speculate that the field induced lattice distortion plays an important role in the solid oxygen α phase.

This paper presents the remaining strength and plastic deformation capacity of the corroded steel member. They are confirmed by an experiment and analysis, about following two cases. 1) Tensile strength is predicted from calculated strength using the minimum of the section average thickness. 2) Shear strength of corroded bolted connection is predicted from calculated strength using average thickness on an expected breaking line.

Anchor-bolt-yield-exposed-column-bases show various restoring force characteristics, that maximum bending moments fluctuate due to axial forces, especially variable axial forces including tension causing many resisting mechanisms. The column-bases with multi-rows of anchor-bolts generally used show multi-linear cyclic curves. The column-bases with anchor-bolts on the centroid axis show discontinuous slip-type cyclic-curves. In this paper, an experimental study on multi-rows of anchor-bolts column bases subjected to variable axial forces including tension and cyclic bending moment were carried out and the experimental results were examined to clarify the resisting behavior of the column bases.

Thoriated-tungsten (ThO2-W) is popularly used for the electrodes of a super-high pressure mercury lamp, or for arcwelding, because of its excellent performance as to the electron emission. Because it is radioactive, however, a new material which can replace it would be desirable. To find a material to replace ThO2W as the electrode, we have made many kinds of electrodes by a new process, which is different from the traditional process, and evaluated their performance. We have found that neodymium oxide or samarium oxide made by the new process produces encouraging results.

We developed a high-speed polarizing microscope imaging system combined with a 37 T pulse magnet. With utilizing this system, we can visualize some kinds of structural transitions induced by high magnetic fields. The efficiency of this system was tested through observation of the field-induced collapse of charge-orbital ordering (COO) in mixed-valent manganites. In perovskite-type Nd1/2Sr1/2MnO3, quantitative analyses of the obtained polarizing microscope images clearly show the discontinuous change in birefringence accompanied with hysteresis, which are characteristic of the first order transitions. This observation of field-induced melting of the COO was also successful in a layered manganite La1/2Sr3/2MnO4 in which changes in magnetization and magnetoresistance at the transition are less clear. The present success in observation of the melting of the COO demonstrates the potential applicability of this system to visualize other kind of structural transitions even in a tiny piece of crystal.

Mandibular reconstruction using particulate cancellous bone and marrow (PCBM) allows functional oral reconstruction. Although ready-made titanium trays are the most common material used in this method, they have some disadvantages such as difficulty in making them form a suitable contour for the defect, and the need for removal. A forged composite of raw particulate hydroxyapatite (HA)/poly-L-lactide (PLLA) is a bioresorbable material that is stronger than pure PLLA and induces bone formation more rapidly. We present two cases successfully treated with custom-made bioresorbable HA/PLLA mesh trays for mandibular reconstruction. A 29-year-old woman with recurrent ameloblastoma and a 66-year-old man with a recurrent keratinized odontogenic tumor of the mandible gave informed consent for this reconstruction technique. Mesh sheets of HA/PLLA were customized by a rapid prototyping method based on computed tomography (CT) data. Marginal resection of the tumor was carried out, and PCBM was harvested from the bilateral posterior iliac crests. PCBM and platelet-rich plasma were transferred to the tray, and the tray was fixed rigidly with HA/PLLA screws. In the second case, dental implants were inserted. There has been no bone resorption for over 2 years since reconstruction in these two cases, and the inserted dental implants have been free from any complications 1 year after loading. The average CT value in Hounsfield units (HU) of the implant sites of two cases was 790. In conclusion, the customized HA/PLLA tray was easily adapted to the mandible, and fine bone quality was obtained. These cases show that this tray system contributed to functional oral rehabilitation with dental implants.

The chemical imaging sensor is a semiconductor-based chemical sensor that can visualize the two-dimensional distribution of specific ions or molecules in the solution. In this study, we developed a miniaturized chemical imaging sensor system with an OLED display panel as a light source that scans the sensor plate. In the proposed configuration, the display panel is placed directly below the sensor plate and illuminates the back surface. The measured area defined by illumination can be arbitrarily customized to fit the size and the shape of the sample to be measured. The waveform of the generated photocurrent, the current–voltage characteristics and the pH sensitivity were investigated and pH imaging with this miniaturized system was demonstrated.

Concerning the bone structures of the mandible reconstructed by particular cellular bone and marrow (PCBM), platelet rich plasma (PRP) and tray, we have examined the possibility of implant insertion by clarifying the morphological conditions in each compact and cancellous bone on computed tomography (CT), and by observing the differences in their CT values. Using the computer software program Sim Plant (Materialize Dental, Leuven, Belgium), we morphologically observed 6 cases of implant inserted area after mandibular reconstruction and 11 cases of native bone, and examined the differences in their CT values. The osseointegration rate of each inserted implant was also evaluated. Compared with the native bone group, the PCBM reconstruction group had generally thin compact bone. In the over-3 cm-length PCBM reconstruction group, the average CT value was 259.7 ± 94.4 HU (n = 3) in the cancellous bone, whereas in the native bone group, the average CT value was 528.9 ± 140.1 HU (n = 10). Therefore, the PCBM reconstruction group showed significantly lower CT value than the native bone group. However, in the under-3 cm-length group, the PCBM reconstruction group showed no significant difference compared with the native bone group. The osseointegration rate of the inserted implants almost 6 months after insertion was 100% in the PCBM reconstruction group and 94.1% in the native bone group. Although the PCBM reconstructed bone had thinner cortical bone and showed lower CT value compared with the native bone, implant insertion was possible.

An experimental study on non-slip-type exposed column bases proposed by the authors, subjected to both cyclic horizontal laodings and variable axial forces in the limits of compression was carried out to make bending moment characteristics of the column bases and to propose models of restoring force characteristics. In addition, the same experiments on conventional exposed column base were conducted to show the effectiveness of the proposed column bases. The following conclusions were drawn from the experimental results:1) The restoring force characteristics of the non-slip-type column bases become linear-from-origin-type under variable axial forces, and the column bases sustain the self-centering performance reducing residual deformation of a building after an earthquake. 2) The energy absorption capability of the proposed column bases is higher than the conventional ones, and the energy absorption capacity is almost the same under between constant and variable axial forces. 3) The gap between the edge of the base plate and the foundation of the proposed column base under variable axial forces in tension and compression becomes smaller than the conventional one. 4) The gap between the base plate and the foundation of the proposed column base is not generated unless the axial force exceeds half of yield strength of all the anchor-bolts, therefore the bending resistance of the column base is not reduced by the shearing resistance of the anchor-bolt in the case of the lift-off of the column base.

This review presents firstly the synthesis of various dendritic hyperbranched polymers with well-defined structures by generation-based growth methodologies using living/controlled polymerization. Secondly, the synthesis of dendritic hyperbranched poly(methyl methacrylate)s (PMMAs) and their functionalized block copolymers using a novel iterative methodology is described. The methodology involves a two-reaction sequence in each iterative process: (a) a linking reaction of α-functionalized living anionic PMMA with tert-butyldimethylsilyloxymethylphenyl (SMP) groups with benzyl bromide (BnBr)-chain-end-functionalized polymer and (b) a transformation reaction of the SMP groups into BnBr functions. This reaction sequence is repeated several times to construct high-generation (maximum seventh generation) dendritic hyperbranched polymers. Similar branched architectural block copolymers have also been synthesized by the same iterative methodology using other α-functionalized living anionic polymers. Surface structures of the resulting dendritic hyperbranched block copolymers composed of PMMA and poly(2-(perfluorobutyl)ethyl methacrylate) segments have been characterized using X-ray photoelectron spectroscopy and contact angle measurements. Solution behaviors of dendritic hyperbranched PMMAs with different generations and branch densities are discussed based on their intrinsic viscosities, g′ values and Rh values. Copyright © 2007 Society of Chemical Industry

An experimental study was carried out on slip-type and non-slip-type exposed column bases subjected to cyclic bi-axial bending moment to investigate restoring force characteristics. Based on test results the following conclusions were drawn:1) Non-slip-type column bases showed non-slip-type multi-linear cyclic curves, linear from the origin at each loading cycle.2) Slip-type column bases showed complicated slip-type cyclic curves, especially in 45-degree cyclic loading because of plastic elongation of the central-row of anchor-bolts.3) Energy absorption performance of non-slip-type column bases on cyclic loading tests was better than that of slip-type ones.

The in-plane resistivity, Hall resistivity and magnetization of graphite were investigated in pulsed magnetic fields applied along the \textit{c}-axis. The Hall resistivity approaches zero at around 53 T where the in-plane and out-of-plane resistivities steeply decrease. The differential magnetization also shows an anomaly at around this field with a similar amplitude compared to that of de Haas-van Alphen oscillations at lower fields. This transition field appears insensitive to disorder, but reduces with doping holes. These results suggest the realization of the quantum limit states above 53 T. As a plausible explanation for the observed gapped out-of-plane conduction above 53 T, the emergence of the excitonic BCS-like state in graphite is proposed., Comment: 15 pages, 6 figures, to be published in J. Phys. Soc. Jpn

A series of dendrimer-like star-branched poly(methyl methacrylate)s (PMMA)s of generations consisting of four branched segments at each junction have been successfully synthesized by developing an iterative methodology. It involves two reaction steps in each iterative reaction sequence, (a) a coupling reaction of the α-functionalized living anionic PMMA with four tert-butyldimethyl-silyloxymethylphenyl (SMP) groups with benzy bromide (BnBr)-chain-functionalized PMMA and (b) a transformation of SMP group into BnBr functionality. By repeating the reaction sequence thrice, the above-mentioned dendrimer-like star-branched (PMMA)s of up to third-generation made up of 4, 20, and 84 PMMA segments and 16, 64, and 256 BnBr termini were synthesized by the first, second, and third iterative processes, respectively. The resulting polymers all were well-defined in branched architecture and precisely controlled in chain length.

A new ABA-type triblock copolymer was synthesized by coupling reaction of anhydride and amine-functionalized telechelic polymers. The two blocks of the copolymer, polystyrene end-functionalized with anhydride group (PS-anh) and poly(arylene ether sulfone) functionalized with aromatic amine groups at the termini (PAES-amn), were synthesized by living anionic and condensation polymerization, respectively. The block copolymer was characterized by size exclusion chromatography (SEC), thermal (DSC and TGA) studies, and the morphology investigated by atomic force microscopy (AFM) and transmission electron microscopy (TEM). The microstructure of the block copolymer was affected by the volume fraction of the constituent blocks.

Dendritic hyperbranched poly(methyl methacrylate)s (PMMA)s, whose branched architectures resemble the “dendron” part(s) of dendrimer, were synthesized by an iterative methodology consisting of two reactions in each iteration process: (a) a coupling reaction of α-functionalized, living, anionic PMMA having twotert-butyldimethylsilyloxymethylphenyl (SMP) groups with benzyl bromide (BnBr)-chain-end-functionalized PMMA, and (b) a transformation reaction of the introduced SMP groups into BnBr functionalities. These two reactions, (a) and (b), were repeated three times to afford a series of dendron-like, hyperbranched (PMMA)s up to third generation. Three dendron-like, hyperbranched (PMMA)s different in branched architecture were also synthesized by the same iterative methodology using a low molecular weight, functionalized 1,1-diphenylalkyl anion prepared fromsec-BuLi and 1,1-bis(3-tert-butyldime-thylsilyloxymethylphenyl)ethylene in the reaction step (b) in each iterative process. Furthermore, structurally similar, dendron-like, hyperbranched block copolymers could be successfully synthesized by the iterative methodology using α-functionalized, living, anionic poly(2-(perfluorobutyl) ethyl methacrylate) (PRfMA) in addition to α-functionalized, living PMMA. Accordingly, the resulting block copolymers were comprised of both PMMA and PRfMA segments with different sequential orders. After the block copolymers were cast into films and annealed, their surface structures were characterized by angle-dependent XPS and contact angle measurements. All three samples showed significant segregation and enrichment of PRfMA segments at the surfaces.