On Jordan Biderivations of Triangular Matrix Rings

Let $R$ and $S$ be rings with identity, $M$ be a unitary $(R,S)$-bimodule and $T=\left(\begin{array}{cc}R & M \\ 0 & S\end{array}\right) $ be the upper triangular matrix ring determined by $R$, $S$ and $M$. In this paper we prove that under certain conditions a Jordan biderivation of an upper triangular matrix ring $T$ is a biderivation of $T$.     

Role of hypaphorine in the toxicity of Astragalus lusitanicus

Hypaphorine, an alpha-N,N,N-trimethyltryptophan betaine, was isolated, for the first time, from Astragalus lusitanicus Lam. (Fabaceae), a plant highly toxic for lambs and goats. This alkaloid was characterized by NMR and MS analysis. Hypaphorine was previously reported to be a convulsive poison. To confirm the toxicity, it was synthesized and tested in goats. Hypaphorine was shown to be non-toxic for goats even at a high dose of 2 g kg(-1) by oral administration.     

Adsorption of phenylphosphonic acid on GaAs (100) surfaces

The adsorption of phenylphosphonic acid (PPA) on GaAs (100) surfaces from solutions in acetonitrile/water mixtures was studied using Fourier transform infrared spectroscopy in attenuated total reflection in multiple internal reflections (ATR/MIR), X-ray photoelectron spectroscopy (XPS), high-resolution electron energy loss spectroscopy (HREELS), and atomic force microscopy (AFM). ATR/MIR in situ showed that the accumulation of PPA molecules near the GaAs surface increased with the water concentration in the solution. For water contents lower than 4%, ATR/MIR and XPS results are consistent with the formation of a low-density monolayer. A mechanism is proposed for H2O percentages lower than 4% involving the creation of interfacial bonds through a Br?nsted acid-base reaction, which involves the surface hydroxyl groups most probably bound to Ga. It was found that the morphology of the final layer depended strongly on the water concentration in the adsorbing solution. For water concentrations equal to or higher than 5%, the amount of adsorbed molecules drastically increased and was accompanied by modifications in the infrared spectral region corresponding to P-O and P=O. This sudden change indicates a deprotonation of the acid. XPS studies revealed the presence of extra oxygen atoms as well as gallium species in the layer, leading to the conclusion that phosphonate and hydrogenophosphonate ions are present in the PPA layer intercalated with H3O+ and Ga3+ ions. This mechanism enables the formation of layers approximately 10 times thicker than those obtained with lower H2O percentages. HREELS indicated that the surface is composed of regions covered by PPA layers and uncovered regions, but the uncovered regions disappeared for water contents equal to or higher than 5%. XPS results are interpreted using a model consisting of a monolayer partially covering the surface and a thick layer. This model is consistent with AFM images revealing roughness on the order of 7 nm for the thick layer and 0.2-0.5 nm for the thin layer. Sonication proves to be an effective method for reducing layer thickness.     

Synthesis and structure determination of a 2D open-framework zincophosphate templated by cyclohexylamine molecules

The synthesis and crystal structure of a new bidimensional zincophosphate (ZnPO) are reported. Zn₂(HPO₄)₂Cl₂·2NC₆H₁₄ crystallizes in the monoclinic space group P2₁/a (n°14) with a = 8.830(3) Å, b = 9.278(3) Å, c = 26.950(9) Å, = 90.74(3)°, V = 2207.7(1) ų and Z = 4. This new material consists of a 2D open-framework of corner sharing ZnO₃Cl and PO₃OH tetrahedra alternating with planes of protonated cyclohexylamine molecules (NC₆H₁₄)⁺. The organic molecules are interconnected to the framework through hydrogen bonds.     

A New Thiophen Acetylene from Artemisia Absinthium

The investigation of the dried roots of A. absinthium afforded two known lignans of tetrahydrofuran skeleton, sesamin and yangambin, one known coumarin, 6‐methoxy‐7,8‐methylenedioxy coumarin and a new thiophen acetylene. The structures were elucidated by spectroscopic methods.     

Quantifying of Quantum Correlations in an Optomechanical System with Cross-Kerr Interaction

Journal of Russian Laser Research - Under the cross-Kerr effect, we investigate two different forms of quantum correlations in an optomechanical system consisting of a mechanical mode coupled with...     

One Pot Synthesis of Bisphosphonate Esters: A Way to Synthesize Tetraphosphonate Esters

Abstract

Several methods for the preparation of symmetrical bisphosphonates of general type (RO)₂P(O)(R′OH)P(O)(OR)₂, have been developed, and investigated for their pharmacological. Pharmacological screening of these bisphosphonates have shown that these compounds have potent cardiovascular activity and are. potentialy useful in the treatment of hypertension. In this work we described of new method “one pot” for the synthesis of hydroxy bis and tetra phosphonates (I, II, III and IV).