Ferromagnetic-like behavior of Bi0.9La0.1FeO3-KBr nanocomposites

We studied magnetostatic response of the Bi0.9La0.1FeO3-KBr composites (BLFO-KBr) consisting of nanosized (about 100 nm) ferrite Bi0.9La0.1FeO3 (BLFO) conjugated with fine grinded ionic conducting KBr. When the fraction of KBr is rather small (less than 15 wt percent) the magnetic response of the composite is very weak and similar to that observed for the BLFO (pure KBr matrix without Bi1-xLaxFeO3 has no magnetic response as anticipated). However, when the fraction of KBr increases above 15percent, the magnetic response of the composite changes substantially and the field dependence of magnetization reveals ferromagnetic-like hysteresis loop with a remanent magnetization about 0.14 emu/g and coercive field about 1.8 Tesla (at room temperature). Nothing similar to the ferromagnetic-like hysteresis loop can be observed in BLFO ceramics, which magnetization quasi linearly increases with magnetic field. Different physical mechanisms were considered to explain the unusual experimental results for BLFO-KBr nanocomposites, but only those among them, which are highly sensitive to the interaction of antiferromagnetic Bi0.9La0.1FeO3 with ionic conductor KBr, can be relevant. An appropriate mechanism turned out to be ferro-magneto-ionic coupling.Comment: 24 pages, 4 figures in the main text, and supplement with 4 figure

Modification of Adhesive Compositions Based on Polar Rubbers with Oligomeric Unsaturated Polyketone

Показана эффективность применения олигомерного ненасыщенного поликетона, полученного путем реакции цис‑1,4-бутадиенового каучука с оксидом азота (I) (N 2O), для модификации клеевых композиций на основе хлоропренового каучука PS‑40A и бутадиен-нитрильного карбоксилатного каучука СКН‑26–5. Установлено, что введение в композиции олигомерного ненасыщенного поликетона, содержащего 9,7 масс.% кислорода в виде карбонильных групп, приводит к повышению прочности склеивания образцов вулканизат-термопласт и вулканизат-вулканизатThe effectiveness of the use of oligomeric unsaturated polyketone obtained by the reaction of cis‑1,4-butadiene rubber with nitric oxide (I) (N 2O) for modification of adhesive compositions based on chloroprene rubber PS‑40A and nitrile butadiene carboxylate rubber SKN‑26–5 is shown. It was found that the introduction of oligomeric unsaturated polyketone containing 9.7 wt.% oxygen in the form of carbonyl groups into the composition leads to an increase in the adhesion strength of the vulcanizate- ‑thermoplastic and vulcanizate- vulcanizate sample