On selfinjective semiprimary rings

In this note, we use a universal algebraic argument to show that modules with 0-limits need not be equationally compact, thus providing a counter-example to an open problem of Jensen and Lenzing.     

Physical- and Bio-Organic Chemstry of Nonbonded Selenium· · ·Oxygen Interactions

Weak nonbonded interaction between a divalent selenium and an oxygen atom (i.e., Se···O interaction) frequently plays important roles in chemical and biological functions of selenium compounds. To establish that ⁷⁷ Se NMR is an easy experimental probe to diagnose the strength of an Se···O interaction, 3 series of 2-substituted benzeneselenenyl derivatives, which have an intramolecular Se···O interaction in solution, were employed. By comparing the ⁷⁷ Se NMR chemical shifts (δ _Se ) with those observed for other series of selenium compounds, which have an intramolecular Se···Y (Y = N, O, F, Cl, or Br) interaction, approximate linear correlation was found between the δ _Se values and the strengths of the nonbonded Se···Y interactions evaluated by natural bond orbital analysis at the B3LYP level. The correlation will be useful for estimating the strength of an Se···O interaction simply from the ⁷⁷ Se NMR chemical shift. By extending the chemistry of nonbonded Se···O interactions to structural biology, analogous S···O interactions have been discovered in protein architecture. The directional features were, however, different from those of Se···O and S···O interactions of small organic compounds.     

The Effect of β-Nitro Group on the Reactivity and the Stereoselectivity of Amidation of Bicyclic Acids by Dehydration with DCC

Amidation of exo/endo mixture of β-nitro bicyclic acids by dehydration with DCC, gives only the corresponding exo-amides.     

Unoccupied band dispersion of Si(1 1 1):√3 × √3-Ag surface studied by time- and angle-resolved two-photon photoemission spectroscopy

Band dispersion and transient population of unoccupied electronic states on Si(1 1 1):√3 × √3-Ag surface have been studied by time-resolved (TR) and angle-resolved (AR) two-photon photoemission (2PPE) spectroscopy. The band dispersions originating from unoccupied electronic states have been identified from the comparison between AR-2PPE spectra and angle-resolved one-photon photoemission spectra with synchrotron radiation. A lifetime of unoccupied surface state has been determined from the TR-2PPE spectra.     

有机过氧化物安定性的差示扫描量热测定

1 引言有机过氧化物是一种自反应性物质.这类物质在制造、使用、贮存过程中或由于自分解发热、热积累导致燃烧、爆炸,或由于冲击、摩擦、电火花、明火等外部作用导致燃烧爆炸而造成人员伤亡.差示扫描量热法(DSC)、压力容器试验法(PVT)是评价这类物质安全性的基本方法.本文利用DSC法对7种有机过氧化物进行了加热分解试验研究,探讨其热安定性、发生热爆炸的难易程度及剧烈程度.     

Ascoli-Arzelà type theorem for rational iterations on the complex projective plane

For a dominant algebraically stable rational self-map of the complex projective plane of degree at least 2, we will consider three different definitions of the Fatou set and show the equivalence of them (Ascoli-Arzelà type theorem). As a corollary, it follows that all Fatou components are Stein. This is an improvement of an early result by Fornæss and Sibony.

     

Laccase‐catalyzed polymerization of lignocatechol and affinity on proteins of resulting polymers

For the synthesis of a new biologically functional polymer from a natural resource by an environment‐friendly method, the laccase‐catalyzed polymerization of a lignin‐based macromonomer, lignocatechol, was carried out for the first time in ethanol–phosphate buffer solvent system to give crosslinked polymers in good yields. Lignocatechol was prepared by the phase separation system of lignin and catechol in aqueous sulfuric acid. The copolymerization was also performed with urushiol to afford the corresponding copolymers in high yields. The polymerization mechanism was estimated by the IR and pyrolysis GC‐MS measurements, suggesting that the polymerization proceeded mainly at the catechol ring through a quinone radical intermediate. The thermal properties were measured by the DSC, TG, and TMA analyses, indicating that the polymers had high thermal stabilities because of the crosslinked structures. In addition, it was found that the resulting polymers had the affinity of bovine serum albumin (BSA) and glucoamylase. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 824–832, 2009     

Characterization of polysaccharides having activity on the reticuloendothelial system from the rhizome of Curcuma longa

Three polysaccharides, named ukonan A, ukonan B and ukonan C, were isolated from the rhizomes of Curcuma longa L. They were homogeneous on electrophoresis and gel chromatography, and showed remarkable reticuloendothelial system-potentiating activity in a carbon clearance test. They are composed of L-arabinose: D-xylose: D-galactose: D-glucose: L-rhamnose: D-galacturonic acid in the molar ratios of 12:4:12:1:4:10 (ukonan A), 12:4:12:1:2:4 (ukonan B) and 8:3:6:14:2:3 (ukonan C), in addition to small amounts of peptide moiety. Methylation analysis, carbon-13 nuclear magnetic resonance and periodate oxidation studies indicated the structural features of ukonan B, the major one in terms of the activity. It has acidic arabino-galactan type structural units.