Photooxidation and photooxygenation of α-diazoketone in alcohol

The investigation of the mechanism of oxidative-cleavage reaction of azibenzil in alcohol to give benzoates revealed the role of oxygen (either ¹0₂ or ³0₂) in the photolysis of α-diazoketone.     

Epitaxial crystallization of polyoxymethylene during cationic polymerization of trioxane

Epitaxial crystallization of polyoxymethylene (POM) during cationic polymerization of trioxane in ethane dichloride was studied. Nascent POM crystals grew epitaxially on the surface of drawn, high-molecular-weight POM and on the (001) surface of KCl single crystals. Half-hexagonal crystals several thousand angstroms in thickness were formed on these substrates. No discrete diffraction maximum could be observed in small-angle x-ray scattering patterns, but diffuse streaks were present on both the equator and the meridian of the pattern. These diffuse streaks are due to inhomogeneities in the nascent crystals. It is proposed that the crystals contain voids due to occlusion of reactive chain ends in the crystal. The optical diffraction pattern from a model made up of rectangles agreed qualitatively with the actual x-ray pattern.     

Semi-classical limit of scattering length

For scattering by a finite range potential, it is shown that the scattering length is convergent to the capacity of the support of the finite range potential in the semi-classical limit. This result has been already proved by use of probabilistic methods. Here we give an alternative proof without using any probabilistic idea. The proof is purely analytical and very simple.     

Note on the non-stationary iterative method for the estimation of the optimum overrelaxation parameter

We study the cause for the overestimation of the optimum overrelaxation factor when a non-stationary iterative method of Carré's or Kulsud's type is used. In addition we show that when the overrelaxation factor is substantially changed the estimation process becomes more difficult. The overestimation phenomena are also shown numerically.     

Synthesis of a Series of Malonic Diester–Introduced Fullerene Derivatives

A facile preparation method for derivatization of fullerene through the Bingel reaction was introduced. A series of fullerene derivatives, to which malonic diester with different substituents were introduced, were systematically synthesized by Bingel reaction. Malonic diester could be added to fullerene at room temperature in the presence of iodine and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), and various substituents such as phenyl, hexyl, thienyl, and pyrenyl were introduced into both sides of the malonic diester. As a result, 17 systematic variations were synthesized. The solubility parameters of the obtained fullerene derivatives calculated by the method reported by Fedors were in the range of 33 to 43 (J cm^?3)^1/2.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]     

Chemical composition of sediments from marine shallow-water hydrothermal mounds in Wakamiko submarine crater revealed by multiple prompt gamma-ray analysis

Multiple prompt gamma-ray analysis (MPGA), a new radionuclide quantification method with high energy resolution, was applied to sediments from a marine shallow-water hydrothermal mound. Surface sediments around mounds were collected from the Wakamiko submarine crater located in Kagoshima Bay, southwest Japan, where the hydrothermal system was different from those at other marine shallow-water hydrothermal mounds. All samples were desalted and MPGA measurements were performed for 4,500?s (real time). Event data were obtained using eight Canberra-Eurisys CLOVER Ge detectors. The size of the list data that included all multiple events was from 1.19 to 19.2?GB. We could obtain concentrations of ³²S, ⁵⁵Mn, ⁷⁵As, ¹⁵⁷Gd, ³⁹K, ¹⁴⁹Sm, ⁵⁶Fe, and ⁸⁵Rb with high sensitivity by MPGA. Furthermore, ³²S, ⁸⁵Rb, and ⁵⁵Mn have characteristic concentrations only at a mound, not at control sampling sites, suggesting that sediments were sulfurated by magmatic fluids at this mound.