Selective Growth and Structural Analysis of Regular MnO Nanooctapods Bearing Multiple High‐Index Surface Facets

Although numerous morphologies of MnO nanostructures have been reported, an exact structural analysis and mechanistic study has been lacking. In the present study, the formation of regular MnO octapods was demonstrated in a simple procedure, comprising the thermal decomposition of manganese oleate. Because of their structural uniformity, an ideal three‐dimensional model was successfully constructed. The eight arms protruded from the cubic center with tip angles of 38° and surface facets of {311} and {533} with rounded edges. The concentrations of oleate and chloride ions were the determining factors for the octapod formation. Selective coordination of the oleate ions to the {100} faces led to edge growth along the <111> direction, which was then limited by the chloride ions bound to the high‐index surface facets. These structural and mechanistic analyses should be helpful for understanding the complex nanostructures and for tuning their structure‐related properties.     

Vibrational Spectra of Magnesium Hydrogenphosphate Trihydrate and of its Manganese Analogue

Abstract

The infrared (IR) and Raman spectra of MgHPO₄. 3H₂O and of a series of partially deuterated analogues as well as the IR spectra of MnHPO₄. 3H₂O have been recorded and interpreted. The analysis of the IR spectra in the HOD bending region rules out the possibility of existence of H₃OC⁺ ions in the structure.     

A Kinetic Method For The Determination Of A Nanogram Amount Of Mercury(ii) By Its Catalytic Effect On The Complex Formation Reaction Of Manganese(11) With α, β, γ δ-Tetraphenylporphinesulfonate

Abstract

Mercury(II) ion accelerates the complex formation reaction of manganese(II) with α, β, γ δ-tetraphenylporohinesulfonate (TPPS). Mercury(II) concentrations as low as 10^?8 mol dm^?3 can be determined from the decrease in absorbance at 413 nm (Λ_max of TPPS) at a fixed time after the initiation of the reaction of rnanganese(II) with TPPS. Sandell's sensitivity calculated from the calibration curve at 30 min after the start of the reaction is 3.8 × 10^?2 ng cm^?2. After the separation of metallic mercury by distillation at room temperature, the method is highly selective and is free from interference of most substances usually encountered.     

Facile Access to 3-Alkyl-Substituted 3-Hydroperoxy-2,4-pyrrolidinediones Using Manganese(III)-Catalyzed Aerobic Oxidation

Abstract

3-Alkyl-substituted 2,4-pyrrolidinediones were directly oxidized under very mild manganese(III)-catalyzed aerobic oxidation conditions to give the corresponding 3-hydroperoxy-2,4-pyrrolidinediones in quantitative yields. The scope and limitations for the synthesis of the hydroperoxyprrolidinediones are described.     

Effect of manganese addition on physical properties of Co0.6Zn0.4MnxFe2-xO4 system

X-ray analysis and magnetic properties have been studied for the system Co_0.6Zn_0.4Mn_xFe_2-xO₄. The bulk density, X-ray density and porosity were also studied. It was found that the lattice constant decreased with increasing manganese concentration x. The X-ray density, the bulk density and porosity do depend on the manganese content. The magnetic susceptibility and the activation energies were found to be increased with increasing percentage of the manganese ions while the dc conductivity decreased.     

Interaction of Cationic Manganese Porphyrins with DNA. A Binding Model

The DNA cleavage properties of two cationic manganese porphyrins possessing different peripheral substituents were compared. The identical nature of the strand scission patterns of the porphyrins on a 139 base pair restriction fragment of pBR-322 DNA, along with other evidence, suggests that the porphyrin is end-on bound via the minor groove in a melted or partially melted region of DNA. This unusual binding mode underscores the potential of outisde binding cationic metalloporphyrins as probes for low melting regions of DNA     

Transferkoeffizienten im System Boden—Pflanze in verschiedenen Lokalitäten der Tschechoslovakei

Für die Ermittlung der Transferkoeffizienten im System Boden–Pflanze wurden in drei Stellen der Tschechoslovakei Boden- und Pflanzenproben entnommen. Die niedrigsten Transferkoeffizienten für Getreide und für mehrjährige Futterpflanzen wurden in der Ostslovakei festgestellt. Die Werte der Transferkoeffizienten waren durch den Bodentyp, den Gesamt-Sorptionskapazität und dem Grad der Sorptionssättigung beeinfluβt.

Soil and plant samples were sampled for the determination of soil to plant transfer coefficients in three various Czechoslovak sites. The lowesl transfer factors for cereals and fodder were determined in the site of Eastern Slovakia. Values of transfer factors depend on soil type, cation exchange capacity and base saturation of soils.     

Manganese(II) tetrasulfophthalocyanine covalently supported on natural silk: A new highly active catalyst for synthesis of benzoxazepine derivatives in water

Natural silk as a biodegradable, biocompatible, renewable, green and abundant biomaterial was used as a support for chemical immobilization of a water‐soluble manganese(II) complex with a phthalocyanine ligand possessing covalent binding ability. The prepared manganese(II) tetrasulfophthalocyanine complex supported on natural silk revealed efficient catalytic activity and reusability for the synthesis of benzoxazepine derivatives in water at room temperature.