Transport anomalies in the layered compound BaPt4Se6

We report a layered ternary selenide BaPt4Se6 featuring sesqui-selenide Pt2Se3 layers sandwiched by Ba atoms. The Pt2Se3 layers in this compound can be derived from the Dirac-semimetal PtSe2 phase with Se vacancies that form a honeycomb structure. This structure results in a Pt (VI) and Pt (II) mixed-valence compound with both PtSe6 octahedra and PtSe4 square net coordination configurations. Temperature-dependent electrical transport measurements suggest two distinct anomalies: a resistivity crossover, mimic to the metal-insulator (M-I) transition at ~150 K, and a resistivity plateau at temperatures below 10 K. The resistivity crossover is not associated with any structural, magnetic, or charge order modulated phase transitions. Magnetoresistivity, Hall, and heat capacity measurements concurrently suggest an existing hidden state below 5 K in this system. Angle-resolved photoemission spectroscopy measurements reveal a metallic state and no dramatic reconstruction of the electronic structure up to 200 K.

Removal of Malachite Green Dye using Keggin Polyoxometalate Intercalated ZnAl Layered Double Hydroxide

The ZnAl Layered double hydroxides (LDHs) have been successfully synthesized by the coprecipitation method, followed by intercalation using Keggin ion of α-dodecatungstosilicic acid [α-SiW12O40]4- to form ZnAl-[α-SiW12O40] LDHs. The prepared ZnAl-[SiW12O40] LDHs were characterized by using X-Ray, FTIR, and BET surface area analyses, which were, then, used as adsorbents of malachite green dye from aqueous solution. The synthesized ZnAl LDH showed a typical diffraction peak of the layered compound at 11o (003) with an interlayer space of 8.59 Å. After intercalation, it was recorded that the interlayer space of ZnAl-[SiW12O40] LDH increased to 10.65 Å. Moreover, the specific surface area of the intercalated LDH increased from 1.9685 to 14.0422 Å. The adsorption study revealed that the adsorption capacity of ZnAl-[SiW12O40] LDH toward malachite green dye was higher (37.514 mg.g-1) than the pristine ZnAl LDH (32.845 mg.g-1). The adsorption kinetics study showed that malachite green adsorption onto both pristine and intercalate LDH followed the pseudo-2nd-order model. The adsorption thermodynamic investigation indicated that adsorption of malachite green onto ZnAl-[SiW12O40] LDH was a spontaneous process and was classified as physical adsorption with activation energy ranging from 10.074 to 15.476 kJ.mol-1. HIGHLIGHTS ZnAl LDH intercalated by Keggin ion has been successfully synthesized by facile coprecipitation followed by ion exchange method The basal spacing of the intercalated ZnAl LDH increased up to 10.65 A The intercalated ZnAl LDH exhibited higher adsorption capacity for malachite green dye removal compared with the original ZnAl LDH

Review: Synthesis, Characterization and Studies on Controlled Release Properties of Layered Compound

Layered inorganic structure such as Layered Double Hydroxide (LDH), zinc layered hydroxide (ZLH) and graphene, in nano-size, have been used widely in the nanotechnology areas as a new and promising problem solving materials. The ability of these inorganic layered compounds that able to encapsulate the organic anions were known to provide greatest benefits; were explained more details in this paper. Intercalations of anion into the interlayer spaces of layered inorganic structure such as anion-exchange, co-precipitation, hydrothermal method and reconstruction with ‘memory effect’ were also explained. The characterization of intercalated layered nanocomposites such as Fourier Transforms Infrared (FTIR) spectroscopy, PowderX-ray Diffraction (PXRD) analysis, Thermogravimetric analysis, surface analysis was used to explain the successful of anion intercalated in between the interlayer spaces of layered inorganic structures. The application of these hybrids that have been widely used such as controlled release properties in pharmaceutical area, antimicrobial studies, dyeing agent, enhancing UV Sunscreen protection, herbicides and water treatment process were also described in details.

Recursive Prosody and the Prosodic Form of Compounds

This paper investigates the role recursive structures play in prosody. In current understanding, phonological phrasing is computed by a general syntax–prosody mapping algorithm. Here, we are interested in recursive structure that arises in response to morphosyntactic structure that needs to be mapped. We investigate the types of recursive structures found in prosody, specifically: For a prosodic category κ, besides the adjunctive type of recursion κ[κ x], κ[x κ], is there also the coordinative type κ[κ κ]? Focusing on the prosodic forms of compounds in two typologically rather different languages, Danish and Japanese, we encounter three types of recursive word structures: coordinative ω[ω ω], left-adjunctive ω[f ω], right-adjunctive ω[ω f] and the strictly layered compound structure ω[f f]. In addition, two kinds of coordinative φ-compounds are found in Japanese, one with a non-recursive (strictly layered) structure φ[ω ω], a mono-phrasal compound consisting of two words, and one with coordinative recursion φ[φ φ], a bi-phrasal compound. A cross-linguistically rare type of post-syntactic compound has this biphrasal structure, a fact to be explained by its sentential origin.

Phase Equilibria of the MnTe-Sb2Te3 System and Synthesis of Novel Ternary Layered Compound – MnSb4Te7

By using Differential Thermal Analysis (DTA) and Powder X-ray Diffraction (PXRD) techniques, the phase diagram of the MnTe-Sb2Te3 system has been constructed for the first time in the entire composition range. The system features two ternary layered van der Waals (vdW) compounds. Apart from known MnSb2Te4, novel MnSb4Te7 which a structural analogous of the known MnBi4Te7 was found in the system. Crystal structure parameters of both compounds were determined by Rietveld refinement using the fundamental parameter approach. Both compounds were found to decompose via peritectic reactions and possess significant homogeneity ranges. The title system is also characterized by the existence of the wide solid solution field based on the starting Sb2Te3. The present results would be useful for the bulk single crystal growth of both compounds from the liquid phase via the determination of primary crystallization areas.