Genicunolide A, B and C: three new triterpenoids from Euphorbia geniculata

Three new triterpenoids, designated as genicunolide A (1), B (2) and C (3), along with friedelin (4) and friedelinol (5), were isolated from the aerial parts of Euphorbia geniculata. They were characterized as 1β-acetoxy-3β-hydroxy-11α,12α-oxidotaraxer-14-ene, 1β,3β-diacetoxy-21α-hydroxy-11α,12α-oxidotaraxer-14-ene and 3β,9α,20α-trihydroxy-Ψ-taraxast-5-ene, respectively, by spectral and chemical methods

Optical and electrical characterization of Ni-doped orthoferrites thin films prepared by sol-gel process

International audienceThis paper presents a low-temperature route for producing RFe0.6Ni0.4O3 (where R = Pr, Nd and Sm) thin films by an aqueous inorganic sol-gel process. The films produced were characterized by X-ray diffraction (XRD) for structural, four probes for electrical and UV-vis spectroscopy for optical properties. As-deposited films were amorphous and after annealing them at 650 °C, crystallinity appears and shows an orthorhombic structure. From UV-vis spectroscopy, variation in optical band gap and transmission is seen with change of rare-earth ions. From electrical resistivity measurement, semiconducting behavior is observed. The difference in activation energy is observed. This variation could be due to the orthorhombic distortion caused by size of rare-earth ion and which may impact the Fe-O-Fe or Fe-O-Ni or Ni-O-Ni bond angle, and hence affects the single particle band width in the present system

Irigenin – an isoflavone: a brief study on structural and optical properties

Irigenin, an isoflavone (mol. formula = C18H16O8), was isolated from the plant Iris hookeriana using dichloromethane as solvent. The compound was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-visible spectroscopy measurements. Structural analysis of XRD data confirmed the orthorhombic structure for the compound. The microstructure of the compound is an aggregate of microcrystals with an irregular morphology. From the UV-visible spectroscopy, the present compound shows indirect allowed transition with an optical band gap (Eg) of around 3.25 eV. The present optical properties of the compound can be utilized in flexible organic electronics applications

Irigenin – an isoflavone: a brief study on structural and optical properties

Irigenin, an isoflavone (mol. formula = C18H16O8), was isolated from the plant Iris hookeriana using dichloromethane as solvent. The compound was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-visible spectroscopy measurements. Structural analysis of XRD data confirmed the orthorhombic structure for the compound. The microstructure of the compound is an aggregate of microcrystals with an irregular morphology. From the UV-visible spectroscopy, the present compound shows indirect allowed transition with an optical band gap (Eg) of around 3.25 eV. The present optical properties of the compound can be utilized in flexible organic electronics applications