Kinetics of the acidic hydrolysis of vinyl derivatives of benzimidazole-2-thione and benzoxazol-2-one and -2-thione

The kinetics of the acidic hydrolysis of seven vinyl derivatives of benzimidazole-2-thione and benzoxazol-2-one and -2-thione were studied by means of polarography. The rate constants and energies of activation of the reaction were determined. The hydrolytic stabilities of the compounds depend on the nature of the heteroring and the site to which the vinyl group is attached.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1532–1535, November, 1982.     

Magnetic,resonant, and thermal properties of Fe<Subscript>0.27</Subscript>Mn<Subscript>0.73</Subscript>S crystals

Fe_0.27Mn_0.73S single crystals were studied. A magnetic transition is detected near 197 K, which is accompanied by anomalies of the thermal, electrical, and resonant properties.     

Iron–nickel alloy from iron meteorite Chinga studied by Mössbauer spectroscopy with high velocity resolution

Study of iron–nickel alloy from iron meteorite Chinga using Mössbauer spectroscopy with improved velocity resolution (measurement and presentation in 4,096 channels) revealed six magnetic components which may be related to various α-Fe(Ni, Co) and γ-Fe(Ni, Co) phases while previous study with low velocity resolution (in 512 channels) revealed only three magnetic components. This new result was in agreement with the scanning electron microscopy study.     

Preparation and characterization of octadecylsilane monolayers on indium–tin oxide (ITO) surfaces

The preparation and characterization of octadecylsilane, C₁₈, monolayers on indium–tin oxide (ITO) have been studied carefully. A reproducible procedure was developed for the formation of C₁₈/ITO employing octadecyltrimethoxysilane (OTMS) as a monomer. The films were studied by means of electrochemistry, wettability, infrared and atomic force microscopy. All these measurements provide evidence for the formation of a disorganized, ‘brush-type’ monolayer with a maximum surface fractional coverage of 0.90±0.04. The surface coverage can be controlled through the silanization time. The applications and implications of such disorganized monolayers in electroanalytical chemistry are discussed.     

4-(2-Hydroxyaryl)-1,2,3-thiadiazoles as a Source of 2-Benzofuranthiolates

Following the Hurd-Mori procedure, 4-(2-hydroxyaryl)-1,2,3-thiadiazoles were synthesized from o-hydroxyacetophenones. Treatment of the products with bases gives 2-benzofuranthiolates which can be involved in alkylation and arylation reactions.     

Electron transition in intercalated disulfide CuCrS<Subscript>2</Subscript>

Electrical, resonant, and magnetic properties of intercalated copper chromium disulfide CuCrS₂ are studied. It is established that CuCrS₂ is an antiferromagnetic semiconductor with Néel temperature T_N=40.7 K and an effective magnetic moment of 4.3µ_B. Anomalies in the electrical, magnetic, and resonant properties of CuCrS₂ are found at T_c=110 K, which suggest an electron transition accompanied by alteration of the valences of the 3d-metal ions.     

Carbon nanotube "T Junctions": formation pathways and conductivity

Using tight-binding molecular dynamics we simulate the formation of single wall carbon nanotube T junctions via the fusing of two nanotubes. We propose energetically efficient pathways for this process in which all atoms maintain their sp(2) arrangements throughout. Recent experimental advances have greatly increased the plausibility of synthesizing T junctions as proposed in the simulations. We further report I-V characteristics of the formed junctions.     

Spectroscopic Study of the Release Kinetics of Water-Insoluble Drug Griseofulvin from Vaterite Containers in Aqueous Medium

Optics and Spectroscopy - The bioavailability improvement of hydrophobic drugs is one of the major problems in pharmaceutical research as required for the enhancement of their therapeutic efficacy....     

Synthesis and properties of a number of salts of N-succinylmethionine

A comparative study has been made of the radioprotector activity of cystamine and the synthesized cobalt and copper salts of N-succinylmethionine. Activity falls in the sequence cystamine-copper salt-cobalt salt.Khar'kov Scientific-Research Institute of Endocrinology and Hormone Chemistry. Khar'kov Medical Institute. Khar'kov Scientific-Research Institute of Medical Radiology. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 86–88, January–February, 1990.