Observation of a half step magnetization in the {Cu-3}-type triangular spin ring

We report pulsed field magnetization and ESR experiments on a {Cu-3} nanomagnet, where antiferromagnetically coupled Cu2+ (S=1/2) ions form a slightly distorted triangle. The remarkable feature is the observation of a half step magnetization, hysteresis loops, and an asymmetric magnetization between a positive and a negative field in a fast sweeping external field. This is attributed to an adiabatic change of magnetization. The energy levels determined by ESR unveil that the different mixing nature of a spin chirality of a total S=1/2 Kramers doublet by virtue of Dzyaloshinskii-Moriya interactions is decisive for inducing half step magnetization.</p

Fire Resistance on Bearing Wall Using Steel & Gypsum

The conventional loadbearing wall systems generally used in Korea are composed of concrete and brick. Which materials have many defaults like long-term construction period and cost increase. Recently in us, a rapid increase in the usage of cold-formed steel section in housing and commercial building construction can widely be seen. The loadbearing wall assembly composed of light gauge-steel and gypsum board can preferably be applied to residential and commercial building of 5 stories or below. In order that light-gauge steel framing can be prevalently introduced in our domestic housing market, the wall assembly must have sufficient fire-resistant performance. Fire-resistant tests were conducted for the load bearing wall specimens of 7.2m² in size and fire tests were carried out on load-bearing wall systems by method of loading condition and unloading condition in full size of specimens in order to certify the fire-resistance properties. Through test results, the temperature slopes of each material such as steel, insulation and gypsum board were obtained, along with the vertical and horizontal deflection of specimens

Anomalous frequency and intensity scaling of collective and local modes in a coupled spin tetrahedron system

We report on the magnetic excitation spectrum of the coupled spin tetrahedral system Cu$_{2}$Te$_{2}$O$_{5}$Cl$_{2}$ using Raman scattering on single crystals. The transition to an ordered state at T$_{N}^{Cl}$=18.2 K evidenced from thermodynamic data leads to the evolution of distinct low-energy magnetic excitations superimposed by a broad maximum. These modes are ascribed to magnons with different degree of localization and a two-magnon continuum. Two of the modes develop a substantial energy shift with decreasing temperature similar to the order parameter of other Neel ordered systems. The other two modes show only a negligible temperature dependence and dissolve above the ordering temperature in a continuum of excitations at finite energies. These observations point to a delicate interplay of magnetic inter- and intra-tetrahedra degrees of freedom and an importance of singlet fluctuations in describing a spin dynamics.Comment: 7pages, 6figures, 1tabl

Unusual spin pseudogap behavior in the spin web lattice Cu3TeO6 probed by 125Te nuclear magnetic resonance

We present a 125Te nuclear magnetic resonance (NMR) study in the three-dimensional spin web lattice Cu3TeO6 which harbors topological magnons. The 125Te NMR spectra and the Knight-shift K as a function of temperature show a drastic change at TS∼40K much lower than the Néel ordering temperature TN∼61K, providing evidence for the first-order structural phase transition within the magnetically ordered state. Most remarkably, the temperature dependence of the spin-lattice relaxation rate T−11 unravels spin-gap-like magnetic excitations, which sharply sets in at T∗∼75K, the temperature well above TN. The spin-gap behavior may be understood by weakly dispersive optical magnon branches of high-energy spin excitations originating from the unique corner-sharing Cu hexagon spin-1/2 network with low coordination number

Transport of Phosphate by Renal Brush Border Membrane Vesicle (BBMV) during Development - Role of the Growth Hormone-

It is well documented that plasma concentrations of Pi (inorganic phosphorus) are higher in developing subjects than in adults. In a previous study, we demonstrated that the Vmax (capacity) of the Na-Pi cotransport mechanism of the renal brush border membrane vesicles was higher in immature than mature rats. In this study, we evaluated the role of a growth hormone in the maintenance of a higher Vmax observed in immature rats. In mature rats, serum Pi, and the tubular reabsorption of Pi (TRPi) increased in the growth hormone treated animals. On the other hand, those values were not changed by growth hormone treatment in immature rats. In kinetic analysis, the Km (affinity) values were not different between the control (growth hormone-untreated) and growth hormone-treated renal brush border membrane vesicles in both immature and mature rats. The Vmax of the immature rats also was not changed by growth hormone treatment. On the contrary, Vmax increased significantly in the growth-hormone treated than the control mature rats. With the above findings, it seems that immature rats reabsorb Pi maximally even in the control state, and it is likely that a growth hormone is responsible for the phenomenon

Magnon bound states vs. anyonic Majorana excitations in the Kitaev honeycomb magnet α\alpha-RuCl3_3

The pure Kitaev honeycomb model harbors a quantum spin liquid in zero magnetic fields, while applying finite magnetic fields induces a topological spin liquid with non-Abelian anyonic excitations. This latter phase has been much sought after in Kitaev candidate materials, such as $\alpha$-RuCl$_3$. Currently, two competing scenarios exist for the intermediate field phase of this compound ($B=7-10$ T), based on experimental as well as theoretical results: (i) conventional multiparticle magnetic excitations of integer quantum number vs. (ii) Majorana fermionic excitations of possibly non-Abelian nature with a fractional quantum number. To discriminate between these scenarios a detailed investigation of excitations over a wide field-temperature phase diagram is essential. Here we present Raman spectroscopic data revealing low-energy quasiparticles emerging out of a continuum of fractionalized excitations at intermediate fields, which are contrasted by conventional spin-wave excitations. The temperature evolution of these quasiparticles suggests the formation of bound states out of fractionalized excitations

Gelatin-layered and multi-sized porous β-tricalcium phosphate for tissue engineering scaffold

The multi-sized porous β-tricalcium phosphate scaffolds were fabricated by freeze drying followed by slurry coating using a multi-sized porous sponge as a template. Then, gelatin was dip coated on the multi-sized porous β-tricalcium phosphate scaffolds under vacuum. The mechanical and biological properties of the fabricated scaffolds were evaluated and compared to the uniformly sized porous scaffolds and scaffolds that were not coated by gelatin. The compressive strength was tested by a universal testing machine, and the cell viability and differentiation behavior were measured using a cell counting kit and alkaline phosphatase activity using the MC3T3-E1 cells. In comparison, the gelatin-coated multi-sized porous β-tricalcium phosphate scaffold showed enhanced compressive strength. After 14 days, the multi-sized pores were shown to affect cell differentiation, and gelatin coatings were shown to affect the cell viability and differentiation. The results of this study demonstrated that the multi-sized porous β-tricalcium phosphate scaffold coated by gelatin enhanced the mechanical and biological strengths