Effects of Saturation and Self-Saturation in Unidirectional-Wave Spectroscopy of Transition between Levels with a Total Moment of J = 1

Optics and Spectroscopy - Nonlinear absorption of a probe field in a system of degenerate levels of an atom characterized by a total moment of J = 1 in unidirectional waves is studied analytically...     

Features of Functionalization of MCM-41 Silica Mesoporous Molecular Sieves during Their Template Synthesis

We have shown that functionalization of MCM-41 mesoporous molecular sieves during their template synthesis using the effect of solubilization of organic hydrophobic co-condensing compounds makes it possible to obtain highly ordered mesoporous molecular sieves, with concentrations of vinyl or allyl groups covalently bonded to the surface of the silica matrix of about 3.5 mmol/g, which after sulfonation have acidic properties and exhibit catalytic activity in the process of ethyl tert-butyl ether synthesis.     

Extractive substances of the bark of Picea obovata

The chemical composition of a petroleum ether extract of the bark of the Siberian spruce has been studied. Extracts included saturated aliphatic alcohols and C₁₆-C₂₄ acids — abietic, dehydroabietic, isopimaric, oleic, lineolic, and linolenic — alkyl ferulates, ketones, and alcohols of the serratene type, and also ⁴-stigmasten-3-one. Onoceradienedione and onoceradienediol — precursors of the serratene triterpenoids — and also a saturated vicinal diol — triacontane-10,11-diol — have been isolated from the extractive substances of conifer in the native form for the first time.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 654–662, November–December, 1992.     

Structure of a new triterpenoid from the bark of the Siberian larch

Sesquiterpene compounds of the furanoeremophilane series have been isolated from extracts of the roots ofCacalia sp. growing in the Soviet Far East. The presence of antioxidant and antiradical activities in two representatives of the series has been established.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 643–646, September–October, 1989.     

Polyfunctional triterpenoids from the bark of Yeddo spruce

The composition of the polyfunctional triterpenoids of an extract of the Yeddo spruce has been studied. Five serratene triterpenoids have been isolated: 21β-hydroxyserrat-14-en-3-one (I), 3β-hydroxyserrat-14-en-21-one (II), serratenediol (III), episerratenediol (XII), and diepiserratenediol (V) in the form of its acetate. The structures of the compounds were confirmed by¹³C NMR spectra and XSA. Novosibirsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 662–667, November–December, 1992.     

Water-soluble proteins of the seeds of some varieties of castor-oil plant

The water-soluble proteins of twelve varieties of castor-oil plant have been studied by electrophoresis. The high hemagglutinating activities of proteins of the seeds is connected with the presence of an electrophoretic component having R_f 0.042.Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 113–116, January–February, 1989.     

The lipids ofHibiscus seeds

The composition and amounts of various classes of lipids of the seeds of Hibiscus sp. have been investigated. Seven classes of neutral lipids, five of phospholipids, and five of glycolipids have been identified and their fatty-acid and triglyceride compositions have been established. The presence has been shown of 16 main types of triacylglycerols and 25 types of epoxyacyldiacylglycerols. An epoxy-18.0 and an epoxy-18:1 acid in a combined amount of 1.4% have been detected among the acids of the free lipids, together with 8.1% of cyclopropenoid acids.Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 40–44, January–February, 1995. Original article submitted October 24, 1994.     

Changes in depth profiles of oxygen and copper in Y-Ba-Cu-O film under annealing

Changes in element depth profiles in a YBaCuO superconducting film on a SrTiO₃ substrate due to one year aging and annealing were investigated by the ion backscattering technique. Crystal perfection of the film was checked by the X-ray rocking curve method. It was found that the film was polycrystalline, with the preferred orientation of thec axis along the normal to the substrate surface with an angle dispersion of 2 °, and that the in-planea andb axes were randomly orientated. The aging experiments have shown that the oxygen content in the surface region increases with the time constant = 20 days. Annealing in a vacuum at 100 °C restores the initial oxygen content. After 2 hours of annealing in an oxygen atmosphere at 400 °C, an unexpectedly strong change in oxygen and copper depth profiles is observed. Since a strong correlation exists between the profile changes, a hypothesis has been advanced about the relationship between oxygen and copper transport in the process of annealing. Taking into account the polycrystalline structure of the film, one can conclude that intergrain diffusion dominates in the oxygen and copper transport.     

Kinetics of the level of lipids in a cotton plant of variety 6524 S during maturation

The composition and amount of lipids in the seeds and leaves of the cotton plant of variety 6524 S over the vegetation periods have been investigated. The rate of biosynthesis of neutral lipids in cotton seeds in the 20-day period after flowering to the moment of maturation increases by a factor of 1.6 while the amounts of phospho- and glycolipids decrease by factors of 3.9 and 4.3, respectively. The fatty acid compositions of the neutral lipids and of the phospho- and glycolipids of the seeds and leaves have been determined.Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbekistan Republic, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 359–362, May–June, 1993.