Charge transfer enhanced magnetic correlations in type-II multiferroic CoTeO.

Magnetic structure of the Co ions in monoclinic CoTeO in the antiferroelectric state at 16 K has been determined by neutron powder together with single-crystal diffractions. The indices of the magnetic reflections that appear at the incommensurate positions were determined by diffractions from a single crystal, which allow to uniquely identify the magnetic modulation vector. There are two crystallographically distinct Co layers.

Enhanced lattice perfection by low temperature thermal annealing in photoelectric (CHNH)PbBr.

The coupling between the organic CHNH cations and inorganic perovskite PbBr framework in a large single crystal of (CHNH)PbBr weighting 13 g was studied using neutron diffraction and inelastic neutron scattering. Two lattice incommensurate (ICM) phases were found, one at higher temperatures, marked ICM, which appeared between 147 and 135 K. The second one, marked ICM, developed below 143 K and remained at 75 K.

Largely Enhanced Ferromagnetism in Bare CuO Nanoparticles by a Small Size Effect.

Magnetic properties of fully oxygenated bare CuO nanoparticles have been investigated using magnetization, X-ray diffraction, neutron diffraction, and Raman scattering measurements. The Langevin field profile is clearly revealed in the isothermal magnetization of 8.8 nm CuO nanoparticle assembly even at 300 K, revealing a 172 times enhancement of the ferromagnetic responses over that of bulk CuO.

Thermoelectric Figure-of-Merit of Fully Dense Single-Crystalline SnSe.

Single-crystalline SnSe has attracted much attention because of its record high figure-of-merit ≈ 2.6; however, this high has been associated with the low mass density of samples which leaves the intrinsic of fully dense pristine SnSe in question. To this end, we prepared high-quality fully dense SnSe single crystals and performed detailed structural, electrical, and thermal transport measurements over a wide temperature range along the major crystallographic directions.

Evidence of High-Temperature Superconductivity at 18 K in Nanosized Rhombohedral Bi Enhanced by Ni-Doping.

Superconductivity in bulk rhombohedral Bi has recently been detected to appear below 0.53 mK and 5.2 μT.

Fault Dynamics of the 1999 Chi-Chi earthquake: clues from nanometric geochemical analysis of fault gouges.

The 1999 Chi-Chi, Taiwan earthquake (Mw 7.6) produced surface ruptures for about 90 km along the north-south trending Chelungpu fault, with surface displacements of up to 12 m. Based on the combination of nanoscopic investigation and geochemistry analysis of core samples from a 450 m long inclined borehole drilled through the slip zone, we suggest the dynamical processes that likely occurred in the northern portion of the Chelungpu fault during the faulting.

Photoenhanced Ferromagnetism in High-K-Containing K-Ni-Cr Prussian Blue Analogues Coated on Rb-Co-Fe Nanocubes.

A large enhancement of the Ni and Cr ferromagnetic moments under UV-light irradiation has been detected in 55 nm thick KNi[Cr(CN)][(HO)]·0.11HO Prussian blue analogues coated on 240 nm RbCo[Fe(CN)][(HO)]·0.56HO nanocubes.

Complex magnetic incommensurability and electronic charge transfer through the ferroelectric transition in multiferroic CoTeO.

Polarized and unpolarized neutron diffractions have been carried out to investigate the nature of the magnetic structures and transitions in monoclinic CoTeO. As the temperature is lowered below 26 K long range order develops, which is fully incommensurate (ICM) in all three crystallographic directions. Below 19.

Engineering and Scaling the Spontaneous Magnetization Reversal of Faraday Induced Magnetic Relaxation in Nano-Sized Amorphous Ni Coated on Crystalline Au.

We report on the generation of large inverse remanent magnetizations in nano-sized core/shell structure of Au/Ni by turning off the applied magnetic field. The remanent magnetization is very sensitive to the field reduction rate as well as to the thermal and field processes before the switching off of the magnetic field. Spontaneous reversal in direction and increase in magnitude of the remanent magnetization in subsequent relaxations over time were found.

Development of Ferromagnetic Superspins in Bare Cu Nanoparticles by Electronic Charge Redistribution.

We report on the results of investigating the ferromagnetic properties of bare Cu nanoparticles. Three sets of bare Cu nanoparticle assemblies with mean particle diameters of 6.6, 8.

Huge Inverse Magnetization Generated by Faraday Induction in Nano-Sized Au@Ni Core@Shell Nanoparticles.

We report on the design and observation of huge inverse magnetizations pointing in the direction opposite to the applied magnetic field, induced in nano-sized amorphous Ni shells deposited on crystalline Au nanoparticles by turning the applied magnetic field off. The magnitude of the induced inverse magnetization is very sensitive to the field reduction rate as well as to the thermal and field processes before turning the magnetic field off, and can be as high as 54% of the magnetization prior to cutting off the applied magnetic field. Memory effect of the induced inverse magnetization is clearly revealed in the relaxation measurements.

Development of a ferromagnetic component in the superconducting state of Fe-excess Fe1.12Te(1-x)Sex by electronic charge redistribution.

The general picture established so far for the links between superconductivity and magnetic ordering in iron chalcogenide Fe1+y(Te(1-x)Sex) is that the substitution of Se for Te directly drives the system from the antiferromagnetic end into the superconducting regime. Here, we report on the observation of a ferromagnetic component that developed together with the superconducting transition in Fe-excess Fe1.12Te(1-x)Sex crystals using neutron and x-ray diffractions, resistivity, magnetic susceptibility and magnetization measurements.

Fine structures of self-assembled beta-cyclodextrin/Pluronic in dilute and dense systems: a small angle X-ray scattering study.

The evolution of the fine structures of self-assembled polypseudorotaxane (PPR) in Pluronic (PL F108) solutions containing dilute to dense beta-cyclodextrin (β-CD) was illustrated for the first time by small angle X-ray scattering (SAXS). Dense β-CD (∼19 w/v%) was found feasible to be dispersed in 24% citric acid solution. 5% of PL F108 formed cylindrical micelles of 1 nm in radius and 8 nm in length in the presence of 24% citric acid through the dehydration of citric acid and citrate.

Large magnetoresistance and charge transfer between the conduction and magnetic electrons in layered oxyselenide BiOCu(0.96)Se.

The electrical and magnetic properties of slightly Cu-deficient BiOCu(0.96)Se have been investigated using neutron and X-ray diffraction, ac magnetic susceptibility, magnetization and electric resistivity measurements. The layered BiOCu(0.

Correlation of thermostability and conformational changes of catechol 2, 3-dioxygenases from two disparate micro-organisms.

We have investigated the structure of recombinant catechol 2, 3-dioxygenase (C23O) purified from two species in which the enzyme has evolved to function at different temperature. The two species are mesophilic bacterium Pseudomonas putida strain mt-2 and thermophilic archaea Sulfolobus acidocaldariusDSM639. Using the primary sequence analysis, we show that both C23Os have only 30% identity and 48% similarity but contain conserved amino acid residues forming an active site area around the iron ion.

Spin polarization and quantum spins in Au nanoparticles.

The present study focuses on investigating the magnetic properties and the critical particle size for developing sizable spontaneous magnetic moment of bare Au nanoparticles. Seven sets of bare Au nanoparticle assemblies, with diameters from 3.5 to 17.

Spin, charge and lattice couplings in Cu-deficient oxysulphide BiOCu0.94S.

The electrical and magnetic properties of slightly Cu-deficient BiOCu(0.94)S are investigated using neutron diffraction, ac magnetic susceptibility, magnetization and electrical resistivity measurements. The Cu spins order in a ferromagnetic arrangement below T(C) = 250 K.

Short range magnetic correlations induced by La substitution in Ho(1-x)La(x)Mn(2)O(5).

Magnetic susceptibility, x-ray diffraction, neutron diffraction and Raman scattering measurements are employed to study the effects of La substitution on the magnetic properties of multiferroic HoMn(2)O(5). 9% and 18% La-substituted compounds crystallize into the same orthorhombic Pbam symmetry as the parent compound. The magnetic responses to an ac driving magnetic field between 40 and 140 K are greatly enhanced by 18% La substitution.

Interplay between the crystalline and magnetic structures in lightly Cr-doped Bi(0.37)Ca(0.63)Mn(0.96)Cr(0.04)O(2.99).

The interplay between the crystalline and magnetic structures of a 4% Cr-doped Bi(0.37)Ca(0.63)Mn(0.

Thermal effects on the activity and structural conformation of catechol 2,3-dioxygenase from Pseudomonas putida SH1.

A bacterium, Pseudomonas putida SH1, which can catabolize phenol, naphthalene, or cresol as the sole carbon and energy source, was isolated from a petroleum-contaminated site in Taiwan. The catechol 2,3-dioxygenase (C23O) was purified from this bacterial strain when grown on naphthalene as the sole carbon and energy source. The enzyme is composed of four identical subunits with a native molecular weight of 128 +/- 5 kD.