Integral Representations,Differentiability Properties and Limits at Infinity for Beppo Levi Functions

The first aim in the present paper is to give an integral representation for Beppo Levi functions on R ⁿ. Our integral representation is an extension of Sobolev's integral representation given for infinitely differentiable functions with compact support. As applications, continuity and differentiability properties of Beppo Levi functions are studied.Our second aim in this paper is to study the existence of limits at infinity for Beppo Levi functions. We also consider the existence of fine-type limits at infinity with respect to Bessel capacities, which yields the radial limit result at infinity.     

Local structure analysis of smoky and colorless topaz using single crystal Al NMR

The angular dependence of the ²⁷Al NMR spectrum was measured for single crystals of smoky and colorless topaz, Al₂SiO₄(F,OH)₂. Smoky topaz was obtained by irradiating high energy neutrons to colorless topaz. The quadrupole coupling constant e²Qq/h and the asymmetry parameter η were obtained from the analysis of the angular dependences of quadrupole splitting of the ²⁷Al NMR spectrum. The local structures around the aluminum atoms in smoky and colorless topaz were discussed from the magnitude and the direction of the electric field gradient. The directions of principal axes of the EFG tensor of ²⁷Al were close to the directions of Al-O and Al-F bonds. The difference in the bond lengths between Al(1)-F(1) and Al(1)-F(2) was found to affect the x and y components of the EFG tensor.     

Bioavailability study of commercial sustained-release preparations of diclofenac sodium in gastrointestinal physiology regulated-dogs.

The gastrointestinal (GI) physiology of beagle dogs was regulated with a combined-treatment of intramuscular pentagastrin (10 micrograms/kg x 2) and intravenous atropine sulfate (0.02 mg/kg x 1). Here, the gastric acidity, the gastric emptying time and the small intestinal transit time in the regulated-dogs were respectively around pH 2, 0.7h and 4h, approximating those in healthy humans. The superiority of the regulated-dogs over the intact dogs was confirmed in comparative bioavailability studies by using two classes of commercial preparations. Both the conventional tablet and the sustained-release capsule of diclofenac sodium exhibited simple and similar average plasma concentration-time curves of free diclofenac in the intact dogs, while the latter preparation is reported to reveal a bimodal plasma curve of the drug in healthy humans. The regulated-dogs, however, permitted a bimodal average plasma pattern of the drug for the capsules due to an approximation of the GI physiology between humans and these classes of the dogs. The combined-treatment of beagle dogs with pentagastrin and atropine sulfate seems to supply a useful animal model in predicting the absorption characteristics of the sustained-release preparations and poor water-soluble drugs.     

Application of stir bar sorptive extraction for wine analysis

Stir bar sorptive extraction (SBSE) coupled with gas chromatography/mass spectrometry (GC/MS) was used to analyse wine samples for three applications: flavour and compositional analysis; 2,4,6-trichloroanisole (TCA), a common off-aroma in wine; and agrochemicals. SBSE was found to be orders of magnitude more sensitive than modern conventional methodology, allowing for lower detection and quantitation levels, and improved confirmation of identity; SBSE often gave better signal to noise in scan mode than other methods in selective ion monitoring (SIM) mode. With the help of their characteristic mass spectra all agrochemicals could be identified unambiguously at concentrations of 10 microg L(-1) in wine and a further 100 constituents were detected in a Cabernet Sauvignon sample. Thus it is now possible to analyse complex samples such as wine by scan mode, with better confirmation of identity, and without sacrificing sensitivity, where previously SIM methodology had to be used.     

Synthesis of New Lithium Ionic Conductor Thio-LISICON—Lithium Silicon Sulfides System

The new lithium ionic conductors, thio-LISICON (LIthium SuperIonic CONductor), were found in the ternary Li₂S-SiS₂-Al₂S₃ and Li₂S-SiS₂-P₂S₅ systems. Their structures of new materials, Li_4+xSi_1−xAl_xS₄ and Li_4−xSi_1−xP_xS₄ were determined by X-ray Rietveld analysis, and the electric and electrochemical properties were studied by electronic conductivity, ac conductivity and cyclic voltammogram measurements. The structure of the host material, Li₄SiS₄ is related to the γ-Li₃PO₄-type structure, and when the Li⁺ interstitials or Li⁺ vacancies were created by the partial substitutions of Al³⁺ or P⁵⁺ for Si⁴⁺, large increases in conductivity occur. The solid solution member x=0.6 in Li_4−xSi_1−xP_xS₄ showed high conductivity of 6.4×10^-4 S cm⁻¹ at 27°C with negligible electronic conductivity. The new solid solution, Li_4−xSi_1−xP_xS₄, also has high electrochemical stability up to ∼5 V vs Li at room temperature. All-solid-state lithium cells were investigated using the Li_3.4Si_0.4P_0.6S₄ electrolyte, LiCoO₂ cathode and In anode.     

exo- and enantioselective cycloaddition of azomethine ylides generated from N-alkylidene glycine esters using chiral phosphine-copper complexes

High diastereo- and enantioselectivities were obtained for the asymmetric 1,3-dipolar cycloaddition of azomethine ylides generated from N-alkylideneglycine esters with dipolarophiles using chiral phosphine-copper complexes as catalysts. Whereas the cycloaddition of azomethine ylides catalyzed by metal salts generally afforded endo-adducts as the predominant product, the present method is the first example of an exo-selective cycloaddition. [reaction: see text]     

Catalytic asymmetric desymmetrization of cyclic meso-1,3- and 1,4-diols by a phosphinite derivative of quinidine

Asymmetric monobenzoylation reactions of cyclic meso-1,3- and 1,4-diols were catalyzed by a phosphinite derivative of quinidine to afford the corresponding monobenzoylated diol with good yield and enantioselectivity. [reaction: see text]     

Preparation and characterization of novel branched beta-cyclodextrins having beta-D-galactose residues on the non-reducing terminal of the side chains and their specific interactions with peanut (Arachis hypogaea) agglutinin

Six novel branched beta-cyclodextrins (betaCDs) having beta-D-galactose residues on the non-reducing terminal of the sugar side chains, namely 6(1),6(4)-di-O-(beta-D-galactosyl)-betaCD (10), 6-O-(beta-D-galactosyl)-betaCD (11), 6(1),6(4)-di-O-(beta-lactosyl)-betaCD (14), 6-O-(beta-lactosyl)-betaCD (15), 6(1),6(4)-di-O-(4'-O-beta-D-galactosyl-beta-lactosyl)-betaCD (18), and 6-O-(4'-O-beta-D-galactosyl-beta-lactosyl)-betaCD (19), were chemically synthesized using the trichloroacetimidate method. The reaction products were separated by HPLC on an amino column into dibranched and monobranched betaCDs. Their structures were confirmed by mass spectrometry (MS) and two-dimensional (2D) NMR spectroscopic analysis. To study the length of the sugar side chains attached to the CD ring, which leads to differences in the functions of the branched CDs, interactions of these compounds with peanut (Arachis hypogaea) agglutinin (PNA) were investigated using an optical biosensor and an inhibition assay based on hemagglutination. The results showed that all branched betaCDs interacted with PNA, and the binding affinity was 18>14>10 and 19>15>11 when the derivatives were compared on the basis of side chain length.     

Asymmetric synthesis of a chroman derivative (vitamin e precursor)

Chromanmethanol $\text{2}$, a chiral intermediate for the synthesis of α-tocopherol $\text{1}$, is prepared from α-hydroxy aldehyde $\text{5}$, which is obtained by an asymmetric synthesis in over 95% ee.