Magnetically quantized continuum distorted waves

A new derivation of continuum distorted-wave theory is presented. It is generalized to magnetically quantized continuum distorted waves. The context is analytic continuation of hydrogenic-state wave functions from below to above threshold, using parabolic coordinates and quantum numbers including m the magnetic quantum number. This continuation applies to excitation, charge transfer, ionization, and double and hybrid events for both light- and heavy-particle collisions. It is applied to the calculation of double-differential cross sections for the single ionization of the hydrogen atom and for a hydrogen molecule by a proton for electrons ejected in the forward direction at a collision energy of 50 keV and 100 keV respectively.     

On a Problem of Hasse for Certain Imaginary Abelian Fields

Let K be the composite field of an imaginary quadratic field Q(ω) of conductor d and a real abelian field L of conductor f distinct from the rationals Q, where (d,f)=1. Let Z_K be the ring of integers in K. Then concerning to Hasse's problem we construct new families of infinitely many fields K with the non-monogenic phenomena (1), (2) which supplement (J. Number Theory23 (1986), 347-353; Publ. Math. Fac. Sci Besançon, Theor. Nombres (1984) 25pp) and with monogenic (3).     

Synthesis,X-ray structure determination and analysis of packing interactions in 9-(1,2-propenyl)-6-carboethoxy-2-methyl-2,3-dihydrofuro[2,3-h]-benzopyran-5H-one

Claisen rearrangement of ethyl-2,4-diallyloxy--carbethoxycinnamate (1) in refluxing DMA afforded ethyl-9-allyl-2-methyl-2,3-dihydrofuro(2,3-h)benzopyran-5H-one-6-carboxylate (2) in a single step. Dehydrogenation with Pd/C (10%) in DPE furnished an unexpected isomeric compound, 9-(1,2-propenyl)-6-carbethoxy-2-methyl-2,3-dihydrofuro[2,3-h]-benzopyran-5H-one (3). This compound, C₁₈H₁₈O₅, crystallizes in the monoclinic space group P2₁/n with unit cell parameters, a = 7.346(1), b = 16.482(3), c = 12.653(2),Å, and = 92.71(1)°. The structure has been solved by direct methods and refined to R = 0.056 for 1719 observed reflections. The coumarin nucleus is planar. The five-membered ring is in envelope-conformation. The crystal structure is stabilized by intra- and intermolecular CHO hydrogen bonds.     

Preparation of Nanoparticles of Barium Ferrite from Precipitation in Microemulsions

Magnetic nanoparticles of barium ferrite (BaFe₁₂O₁₉) have been synthesized using a microemulsion mediated process. The aqueous cores of water-in-oil microemulsions were used as constrained microreactors for the precipitation of precursor carbonate and hydroxide particles. These precursors were then calcined at 925°C for 12h, during which time they were transformed to the hexagonal ferrite. The pH of reaction was varied between 5 and 12, and it was found that the fraction of non-magnetic hematite (-Fe₂O₃) in the particles varied with the pH of reaction, thus affecting the magnetic properties of the particles. The same precursor particles were also prepared by bulk co-precipitation reaction for comparison. It was found that the microemulsion derived nanoparticles of barium ferrite had both higher intrinsic coercivity (H_c) and saturation magnetization (_s) than the particles derived from bulk co-precipitation. Particles were analyzed by electron microscopy, X-ray diffraction, differential thermal analysis (DTA), thermogravimetric analysis (TGA) and vibrating sample magnetometry (VSM). The best barium ferrite particles produced by the microemulsion synthesis method yielded an intrinsic coercivity of 4310Oe and a saturation magnetization of 60.48emu/g.     

Archimedean Synthesis and Magic Numbers: "Sizing" Giant Molybdenum-Oxide-Based Molecular Spheres of the Keplerate Type

Pythagorean harmony can be found in the spherical polyoxometalate clusters described here (see illustration for an example of a structure), since there are interesting relationships between the so-called magic numbers (12, 32, 42, 72, 132) relevant for spherical viruses and the number of the building blocks in the cluster. The size of these Keplerate clusters can be tailored by varying the type of connections between the pentagons by means of different spacers.     

Development of a stereo-TV system for recording and measurement

The development and use of a stereo-TV system to observe, record and measure spatial coordinates is described.     

Novel synthesis of (1-acetylindol-3-yl)methyl acetate and its displacement substitution reactions

The acylation of gramine produces (1-acetyindol-3-yl) methylacetate from which the 3-alkoxy or thioacid derivatives have been synthesized.