Cluster magnetism in doped InSb

Magnetic properties of indium antimonide doped by Mn and by, simultaneously, Mn and Zn, and Mn and Cd have been analyzed. It has been established that the basic contribution to the formation of the magnetic properties of these materials comes from clusters, whose composition and Curie temperature change depending on the content of manganese, zinc, and cadmium.     

Mössbauer study and magnetic properties of M-type barium hexaferrite doped with Co + Ti and Bi + Ti ions

Using X-ray powder diffractions, M?ssbauer spectroscopy, and magnetic measurements, the effect of complex dopants (Co2+ + Ti4+) and (Bi3+ + Ti4+) on the fine structure and magnetic properties of M-type barium hexaferrite prepared by hydroxide and carbonate precipitations has been studied. The distribution of cations over five nonequivalent positions of barium hexaferrite with magnetoplumbite structure is discussed. It has been shown that doped barium hexaferrite can be used for high-coercitivity data storage media.     

Study of the physicochemical properties and film structure of ternary graft copolymers of aromatic polyimide, ɛ-caprolactam,and ω-dodecanelactam

The microstructure of films of ternary graft copolymers of aromatic polyimide, ?-caprolactam, and ω-dodecanelactam has been studied by atomic force microscopy. It is shown that an increase in the content of ω-dodecanelactam units in copolymers leads to an increase in the diameter of spherulites composed of fibrils. Simultaneously, water absorption decreases and the mechanical properties and crystallinity of copolymer films change.     

The growth of a single crystal of Sr3CuIrO6 and its magnetic behavior compared to polycrystals

We have grown single crystals of the psuedo-one-dimensional compound Sr₃CuIrO₆, a K₄CdCl₆-derived monoclinic structure with Cu-Ir chains along the [101] direction. We present the ac and dc magnetization behavior of the single crystals in comparison with that of the polycrystalline form reported earlier. There is a distinct evidence for at least two magnetic transitions, at 5 K (T ₁) and 19 K (T ₂), with different relative magnitudes in the single and polycrystals. The low temperature magnetic relaxation behavior of both the forms is found to be widely different, exhibiting unexpected time dependence.     

Lithium-cation Conduction and Crystallochemical Features of Solid Solutions La2/3 – x Li3x□4/3 – 2x Nb2O6 with the Structure of Fault Perovskite

Transport properties and crystallochemical features of lithium-containing lanthanum metaniobates La_{2/3 – x} Li_{3x4/3 – 2x} Nb₂O₆ with the structure of fault perovskite are studied. The materials studied have high conductivity by lithium ions. A correlation between the conductivity magnitude, chemical composition, and crystallographic parameters is found.     

A New Synthesis of Calcium N-(5-Hydroxynicotinoyl)-L-glutamate and Its X-ray Diffraction Structure

Russian Journal of Organic Chemistry - A new synthesis of N-(5-hydroxynicotinoyl)-L-glutamic acid via a 5-hydroxynicotinic acid imidazolide intermediate has been developed. Its calcium salt...     

Mechanochemical Pretreatment for Efficient Solvent-Free Synthesis of SSZ-13 Zeolite

The economical and environmentally benign synthesis of SSZ-13 zeolite was possible due to the mechanochemical activation of dry reagents by planetary mill. Contrary to manual grinding in a mortar, the proposed automatized approach is scalable and reproducible. This solvent-free process provided a huge gain in product/gel ratios, significantly minimized reaction space and organic structure-directing agent use, and allowed for the elimination of agitation. Obtained materials were comparable to the product of “classical” syntheses. The use of different silica sources resulted in SSZ-13 zeolites with various characteristics: different Si/Al ratio and crystal size.     

Synthesis and properties of magnetic semiconductor InSb〈Mn,Cd〉

Polycrystalline indium antimonide samples codoped with manganese (0.8–1 at %) and cadmium (3.9 at %) are prepared by quenching from melt. Despite the high contents of these dopants, only InSb maxima are observed in X-ray diffraction patterns of these samples. As probed by magnetic studies, the samples are ferrimagnets having Curie points of about 577 K and room-temperature specific magnetizations of σ ≈ 0.5 G cm³/g (H = 6 kOe). We suggest that the magnetic properties of the samples are dictated by InSb〈Mn,Cd〉 microinclusions, which are located in grain boundaries and dislocations.     

The composition of the plants’ extracts included in the herbal mixtures used to treat the parodontal disease

The methods of gas-liquid chromatography and mass-selective detection were used to determine the composition of the volatile fraction of plant extracts included in herb mixtures used for treating parodontal disease. The following marker substances were found: naphthalene derivatives for pot marigold, furan derivatives for trifid bur-marigold and burnet, and the specific terpenoids for licorice, milfoil, and wild marjoram. All the plants used in the herb mixture, except for pot marigold and cinquefoil, were analyzed (ion-exclusion chromatography) for the content of lower carboxylic acids. It was established that the specific acids for the wild marjoram and licorice are ascorbic and the succinic acids, respectively.