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The Fe–Ni–O system designed for producing bimetal-containing composite anodes of solid oxide fuel cells (SOFCs) was studied. The solubility of nickel in the structure of spinel (Fe,Ni)3O4 ± δ at atmospheric oxygen pressure is ~1/3. Moderate reduction at 1023 K and p(O2) ≈ 10–20 atm leads to partial decomposition of spinels, forming an electron-conducting phase (Fe,Ni)1–yO and submicron bimetallic Fe–Ni particles on the oxide surface, which have potentially high catalytic activity. The electron conductivity has a thermally activated character and increases substantially during the reduction. In the anode conditions of SOFCs, the electric conductivity reaches 30–100 S/cm, while the thermal expansion coefficients are ~12 × 10–6 K–1, which ensures compatibility with solid electrolytes. At the same time, significant volume changes during the redox cycling (up to ~1% on the linear scale) necessitate the introduction of additional components such as yttria-stabilized zirconia (YSZ). The polarization resistance of the model composite anode of reduced Fe2NiO4 ± δ and YSZ deposited on the YSZ solid electrolyte membrane was ~1.8 Ohm cm2 at 923 K in a 4% H2–Ar–H2O atmosphere.

Principal hydrodynamic characteristics of buckwheat drying process by superheated steam are determined. Buckwheat layer hydraulic friction value behavior as drying progresses is ascertained. Criterion equation connecting hydraulic friction coefficient and Reynolds number is obtained.

Five synergistic combinations of biocides have been identified, of which kathon plus copper sulfate is the most efficient against Serratia marcescens. Depending on the ratio of the biocides, the active concentrations needed to maintain the synergistic effect can be decreased 4- to 20-fold. Combinations of biocides with salts promoting steel passivation (such as carbonates and phosphates) have been developed, which are more potent in decreasing corrosion-induced losses of mild steel than biocides and salts taken in isolation. Biocides should be introduced into systems susceptible to biocorrosion at the start of their exploitation, otherwise higher concentrations or synergistic compositions have to be used.

Reaction of Ti(O-n-Bu)4 (TBT) with AlR3 (R = Me, Et,i-Bu) in solvents such as R2O, Py, and Et3N, reduces Ti(IV) to Ti(III), Ti(II), or Ti(I). The organotitanium compounds formed by the reaction of TBT with organoaluminum compounds (OAC) undergo homolytic decomposition at the σ bond in Ti-C. Isotopic exchange analysis using C2D4 suggested the formation of particles containing Ti-CH2CH2-Ti, Al-CH2CH2-Al, Al-CH2CH2-Ti, M=CHCH3, and MM′CHCH3 (M, M′ = Al or Ti) fragments. An ESR spectral analysis established that reaction of TBT with TEA in R2O, Py, and Et3N environments produced two types of paramagnetic complexes, precursors of active centers of ethylene dimerization. The influence of various factors on the kinetics of accumulation and consumption of these complexes was investigated and their structures are suggested.

The formation and properties of active centers were studied in the dimerization of ethylene and polymerization of acetylene in the Ti(O-n-Bu)4-AlEt3 system, in heteroatomic solvents. The absence of ionic stages in the dimerization in dibutyl ether was established. Reaction of ethylene, acetylene (A), and phenylacetylene (PA) with the paramagnetic Ti(I) complex, producing butene-1 or polyacetylenes, a paramagnetic complex, and diamagnetic products, was established for the first time. The effect of such factors as T, [Ti]0, Al/Ti, and M/Ti on consumption and accumulation kinetics of paramagnetic products was studied. Formation of a carbon-centered radical, produced by A or PA joining Ti(I) in the oxidation process, and whose further transformations cause derivation of all the above-mentioned products, was suggested. A probable mechanism was suggested for dimerization of ethylene to butene-1, with intermediate formation of titanacycles.

The article is devoted to the conference which took place in the Chinese Institute of Russian. The contributor throws some light on the peculiarities of organizing and conducting the conference as well as participants' performances united by a common problem of identity in the global world.

Limited proteolysis has established that the protective antigen (PA) molecule consists of four functional-active domains. So, the shielding domain borrows an area in the linear structure of the PA molecule with NH2 of the end up to Lys 166 and plays a conducting role in the proteolytic activation of PA. The associative domain, engaging in the area Arg 167-Met266, plays a key role in the interaction with LF or EF at self-assembly toxic complexes LT or ET. The stabilizing domain borrows in the linear structure of the PA molecule are with Gly351 up to Met434. On the one hand, this area promotes formation with LF conformationally steady toxic complex's, and, on the other, takes a direct participation in the formation of a hydrophobic channel by which the molecule LF or EF enters the target cell. The receptor domain, representing a COOH-terminal area, starting from Leu663 amino acid, begins to interact with specific receptors on the macrophages and thus delivers the toxic complex to the target cell. It has been found that in the molecule of lethal factor there are 3 functionally active domains located in the linear structure of the molecule as follows: the associative domain borrows an area from Lys39 up to Met242, stabilizing and effector domains occupy areas from Leu517 to Lys614 and from that point to Lys COOH-terminal amino acid.

Three functional domains were revealed in the molecule of the lethal factor of B. anthracis. They are located in the linear structure of the molecula as follows: the associative domain occupies the area from Lys39 to Met242, the stabilizing domain from Leu517 to Lys614, and the effector domain still further to the COOH-terminal Lys mino acid.

Using the limited proteolysis method, we established that the protective antigen (PA) molecule consists of four functionally active domains. The shielding domain occupies an area in the linear structure of the molecule PA with NH4-terminal up to Lys166 and plays an important role in the proteolytic activation of PA. The associative domain situated in the Arg167-Met266 region is responsible for interactions with either lethal or edematous factors in self-assembly of the toxic complexes of the lethal or edematous toxin. The stabilizing domain occupies the Gly351 to Met434 area. On the one hand, this area promotes the formation of conformationally stable toxic complexes with the lethal factor, on the other, directly participates in the formation of the hydrophobic canal, through which the molecule of the lethal or edematous factor and, evidently, a fragment of PA molecule as well (from Arg167 to Gly314), including the associative gene, gets inside the target cell. The receptor domain representing a COOH-terminal region, starting from Leu663 amino acid, interacts with the specific receptors on macrophages and thus delivers the toxic complex to the target cell.

The aim of this communication is development of the methods of production, study of the structure and properties of polyethylene-polyacetylene composites.

Antitoxic therapeutic sera produced by the method "Diaferm-3" (devised at the Institute of Epidemiology and Microbiology of the USSR Academy of Medical Sciences) are contaminated in the process of production with group-specific substances and extraneous enzymes contained in crude preparations of swine pepsin. These ballast substances have a negative influence on the process of purification and the stability of antitoxin during the storage of the sera and constitute one of the reasons of their high reactogenicity.

A purified preparation of ATPase (factor F1) from the Acholeplasma laidlawii was obtained. The purification procedure included extraction of the enzyme complex from the isolated membranes by ultrasonication, chromatography on DEAE-cellulose and gel filtration on Sepharose 6B. The specific activity of the ATPase was increased 30-fold as compared to the original activity. The Km value for ATP hydrolysis was 7,4 . 10(-4) M. ADP competitively inhibited the enzyme (Ki = 2,0 . 10(-4) M). Ouabain (2,5 . 10(-4) M) and dicyclohexylcarbodiimide (1,0 . 10(-4) M) did not inhibit the ATPase activity. The enzyme was activated by Mg2+, but was inhibited by a combination of Na+ and K+. The enzyme is cold-labile, but can be stabilized by storage in buffer solutions, containing methanol, glycerol or lecithin.

The conditions of cultivation, ensuring the maximum accumulation of intracellular thermolabile enterotoxin in the cultures of two E. coli strains of different origin, have been studied. Culture media manufactured in the USSR have been selected and the conditions of cultivation, necessary for obtaining intracellular thermolabile enterotoxin in preparative amounts, have been established. Under these conditions the yield of thermolabile enterotoxin in 1.4 mg per 1 liter of culture medium for strain H74-114 and 1.0 mg per 1 liter of culture medium for strain 86.

Pretreatment of the cultures of human peripheral blood leukocytes and splenocytes with the incubation medium of the mitogen-stimulated human lymphoid cells containing various concentrations of lymphokines (including 10 to 1280 units/ml of immune interferon) resulted in increased (by at least 4 times) production of interferon, induced by staphylococcal enterotoxin A, phytohemagglutinin and mitogen from Phytolacca americana (PWM), as well as in intensification of DNA synthesis in the producing cells. A more pronounced specific binding of the inductor labeled with radioactive iodine to the producing cells was also observed.