Capture of volatile chlorinated hydrocarbons by aqueous solutions of branched cyclodextrins

The use of aqueous solutions of branched cyclodextrins was examined in order to develop an effective method of capturing toxic volatile chlorinated hydrocarbons such as trichloroethylene and monochlorobenzene. From the experiments in which trichloroethylene diluted with nitrogen gas came into contact with aqueous solutions of branched cyclodextrin mixtures, it was found that absorption could be performed without the formation of inclusion complex solids, which should simplify the whole process of absorption and recovery.     

MnTaO2N: Polar LiNbO3‐type Oxynitride with a Helical Spin Order

The synthesis, structure, and magnetic properties of a polar and magnetic oxynitride MnTaO₂N are reported. High‐pressure synthesis at 6 GPa and 1400 °C allows for the stabilization of a high‐density structure containing middle‐to‐late transition metals. Synchrotron X‐ray and neutron diffraction studies revealed that MnTaO₂N adopts the LiNbO₃‐type structure, with a random distribution of O^2? and N^3? anions. MnTaO₂N with an “orbital‐inactive” Mn²⁺ ion (d⁵; S=5/2) exhibits a nontrivial helical spin order at 25 K with a propagation vector of [0,0,δ] (δ≈0.3), which is different from the conventional G‐type order observed in other orbital‐inactive perovskite oxides and LiNbO₃‐type oxides. This result suggests the presence of strong frustration because of the heavily tilted MnO₄N₂ octahedral network combined with the mixed O^2?/N^3? species that results in a distribution of (super)‐superexchange interactions.     

Ogawa’s nipponium and its re-assignment to rhenium

Foundations of Chemistry - We re-examine the history of the element “nipponium” discovered by a Japanese chemist Masataka Ogawa in 1908. Since 1996 H.K. Yoshihara has made extensive...     

A convenient synthesis of diacyl sulfides using a novel sulfur transfer reagent

Various diacyl sulfides were synthesized by reaction of acyl chlorides with LiAlHSH. Reaction of glutaryl chloride with LiAlHSH afforded glutaric thioanhydride. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:633–635, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10217     

Copolymerization of 3,3,3-trifluoro-1,2-epoxypropane with N-phenylmaleimide using organozinc initiators

Novel copolymers consisting of 3,3,3-trifluoro-1,2-epoxypropane (TFEP) and N-phenylmaleimide (PMI) units were prepared by the copolymerization of TFEP with PMI initiated with an organozinc compound. Using [Zn(OCH₃)₂ · (C₂H₅ZnOCH₃)₄] as an initiator, the copolymer chains consisted mainly of TFEP-TFEP sequences. The TFEP-PMI sequence content in the copolymer chains was small. On the other hand, using (C₂H₅ZnOCH₃)₄ as an initiator, only low molecular weight copolymers were formed. Those copolymers were suggested to have block structure, poly(TFEP)-block-poly(PMI), by the ¹⁹F NMR analysis. The copolymers showed higher thermostability than poly-(TFEP).     

Fabrication of fluorocarbon polymer-coated silver hollow-glass waveguides for the infrared by the liquid-phase coating method

Fluorocarbon polymer-coated silver hollow-glass waveguides have been fabricated based on the method of silver mirror reaction for silver, and the dipping method for the fluorocarbon polymer. The waveguides show low-loss properties for the infrared wavelengths except for the wavelength regions of large absorption of the polymer. Er:YAG laser light has been successfully transmitted through the flexible waveguides with small bending losses.