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The morphological and physiological characteristics of Bacillus thuringiensis strains were analyzed and conditions for obtaining culture fluid with maximum yield of secreted RNases were determined. Zymographic analysis showed that culture fluid of B. thuringiensis strains along with low-molecular-weight (15-20 kDa) RNases contained enzymes with a molecular weight ~55 kDa and their content depended on the duration and conditions of culturing. Preparations based on B. thuringiensis culture fluid were effective against human influenza virus A/Aichi/2/68 (H3N2). In experiments on mice infected with 10 LD50 influenza virus strain A/Aichi/2/68 (H3N2), we selected effective variants of preparations based on culture fluid of B. thuringiensi strains for preventive administration that provided reliable protection of infected animals (protection coefficient 50%), close to that of the reference drug Tamiflu.

The results of studies of a newly isolated Serratia species K-57 strain are presented. The strain is characterized by antiviral activity towards human influenza A/Aichi/2/68/H3N2, vaccinia, mouse smallpox, and herpes simplex-2 viruses. The detected characteristics of the strain, including the data on activities on nucleolytic enzymes, recommend it for the development of therapeutic and preventive antiviral drugs.

Genetic and biochemical methods and morphological examination were used to study microorganisms isolated from samples of deep drilling of the Lake Baikal bottom sediments. Based on blot hybridization patterns, the strains investigated were divided into several groups according to the degree of homology of their genomic DNA. Morphological, biochemical, and ultrastructural characteristics of bacterial strains are described, and their compliance with the genomic analysis data is demonstrated.

The method of molecular dynamics in explicit solvent was applied to test the hypothesis of the existence of a self-inhibited form of chymosin in solution. The paths and energies were calculated for chymosin in solution and in a crystalline environment. The modeling revealed that the intermolecular contacts of chymosin in crystal have negligible influence on the energy stabilization of its self-inhibited conformation. On the other hand, upon molecular dynamics simulation of the active and self-inhibited forms in solution their conformational energies proved to be quite close and the potential barrier between them relatively low. All this supports the possibility of chymosin to adopt spontaneously the self-inhibited conformation in solution, and indicates that it is one of the really existing enzyme forms rather than a crystal packing artifact. The results obtained open novel approaches to studying the specificity of chymosin as well as other aspartic proteinases.

In addition to previous studies, 30 crystal structures of retroviral proteases corresponding to the highest resolution were inspected to analyze the interactions of the active carboxyls with surroundings groups. The outer oxygens of the active carboxyls in retroviral enzymes form contacts only with the water molecule participating in catalysis. This is an important difference between retroviral proteases and pepsin-like enzymes, which form a net of hydrogen bonds of these outer oxygens with residues neighboring the catalytic site in 3D structures. At the same time, it was found that in all aspartic proteases the inner oxygens of the active carboxyls are also involved in the chain of interactions through peptide groups Thr–Gly adjacent to the active residues. Polarization of these peptide groups influences the donor–acceptor properties of the active carboxyls. The found chain of interactions is more extensive in retroviral than in pepsin-like proteases; however, its main part is conserved for the whole class of these enzymes. Some implications of the role of these interactions are discussed.

Immobilization of biocatalysts on several inorganic monolithic supports has been studied. Transition metals added to TiO2, α-Al2O3 and aluminosilicate change the specific protein binding and support capacity. It is shown that immobilized biocatalysts are stable and can be used to run complex biotechnological processes.

Complex cuprates of the compositions Bi1.6Pb0.4Sr1.8Ca2Cu3Oy and Bi1.7Pb0.2Sb0.1Sr2Ca2Cu3Oy are synthesized. The electrical properties of the superconductors prepared are investigated. Thin films based on the bismuth cuprates studied are produced. It is demonstrated that the thin films prepared can be used as electrodes being in contact with a solid electrolyte for designing oxygen partial pressure gauges.

1. Under the action of sodium methoxide in methanol 2,3-epoxypinane forms trans-2(10)-pinen-3-ol (mixture ofl- and dl-forms) and 3-pinanone (mixture of d- and dl-forms). 2. Under the conditions of the reaction of 2,3-epoxypinane with methanol 3-pinanone may be formed in two ways: 1) mainly directly by the isomerization of the epoxide into the ketone, and 2) by the isomerization of the primary reaction product 2(10)-pinen-3-ol under the action of the base.

1. The primary oxidation of terpinolene at the semicyclic double bond was confirmed, and it was shown that the dioxide has a trans-structure. 2. Terpinolene monoxide exists in solution in the form of a mixture of two half-chair forms; for the dioxide the boat conformation is stable.

1) The main part (61.5–73.4%) of the total amount of aromatic compounds which are present in catalytic gas oils are polycyclic compounds. 2) The polycyclic aromatic compounds consist of both pure aromatic and of hydroaromatic hydrocarbons; no more than one naphthene ring being present in a molecule of the latter hydrocarbons. The number of caron atoms in the side chains is 1.3–2.4. 3) In comparison with phenol, furfurole has a higher selectivity with respect to the polycyclic aromatic compounds. 4) The dissolving capacity of the phenol is somewhat higher for phenol than for furfurole. 5) The temperature range for this extraction of catalytic cracking gas oil by furfurole is 1.5 times greater than for phenol. 6) The optimum furfurole flow rate for the extraction of catalytic cracking gas oil is 100% by volume based on the raw material.

1. In a study of the selective extraction of heavy gas oils produced by catalytic cracking of vacuum distillates from different crude sources, it was shown that raw material with a C. I. above 120, for the production of special carbon blacks, can be obtained by using zeolitic catalyst in the cat cracker, with a subsequent extraction operation on the heavy catalytic gas oil distilling above 350‡C. 2. In order to obtain raw material with sulfur content below 1.8% for the production of highly structurized, very fine carbon blacks, and high-sulfur feedstock used in catalytic cracking must first be hydrotreated; alternatively, the cat cracker may be operated on feedstock cut from low-sulfur crudes. In either case, the heavy catalytic gas oil is extracted to obtain the desired raw material for carbon black production.

A study was made of the isomerization of 2,3-epoxypinane and 3,4-epoxycarane by means of lithium diethylamide. 2,3-Epoxypinane is isomerized into trans-2(10)-pinen-3-ol, whereas 3,4-epoxycarane forms a mixture of alcohols: 3(10)-caren-4-ol, p-mentha-1,5-dien-8-ol, and m-mentha-4,6-dien-2-ol.

1. In Cr−Ni martensitic steels with 11% Cr and 9% Ni the α→γ transformation at heating rates below 50 deg/sec is accompanied by redistribution of chromium and nickel between the α and γ phases. 2. The austenite formed in the partial α→γ transformation contains more chromium, nickel, and probably more molybdenum than the α phase. 3. The enrichment of austenite in chromium, nickel, and other elements in the process of the α→γ transformation in steels of the Kh11N9 type is evidently one reason for the stabilization of austenite during tempering of these steels at α→γ transformation temperatures.

1. We synthesized terpinolene monoxide (4,8-epoxy-p-menthene-1) and dioxide for the first time and confirmed their structure from their NMR and IR spectra. 2. The isomerization of 4,8-epoxy-p-menthene-1 under the influence of zinc bromide was studied. Two isomeric ketones with the composition C10H16O were isolated in individual form; analysis of their PMR spectra provided a basis for assigning them a seven-member ring structure.

1. A feasibility study has been carried out for the utilization, in carbon black production, of the heavy tars obtained in existing USSR ethylene units operating on naphtha, gaseous hydrocarbons, or mixed feedstocks. 2. The heavy-tar yield amounts to 3 to 5% of pyrolysis feedstock weight. 3. In the majority of cases, the heavy tar now being produced will satisfy the requirements imposed on the quality of prospective raw materials for carbon black production.

1. Glycyl-L-proline, L-prolylglycine, benzyloxycarbonyl-L-proline, and glycyl-L-proline anhydride were synthesized and were obtained in the form of monocrystals. 2. The first stage of the x-ray structure analysis of the synthesized compounds was carried out.

1. The gas oil cuts obtained by cat cracking vacuum distillates from most domestic [USSR] crudes can be used as starting material in the production of carbon black, with use of the extraction method. 2. The total content of bi- and polycyclic naphthenes and aromatics in the cat cracker feed can be used to determine the approximate yields of the gas oil cuts. 3. If the hydrocarbon composition is known for the cat cracked gas oil (270–420°C or 195–420°C), the curve given in Fig. 3 can be used to determine the yield of extract, i.e., the yield of carbon-black feedstock. 4. This investigation was performed with amorphous aluminosilicate catalysts, but the conclusions may be extended to zeolitic catalysts as well. The only factor that should be kept in mind is that the conversion of hydrocarbons (primarily paraffinic) is higher on zeolitic catalysts, so that the cat cracked gas oil cuts will be more highly aromatic but the yields of gas oil will be lower. However, the extract yield, calculated on gas oil, will be higher.

The hydrolysis of chloroacetophos in water includes the parallel cleavage of acetic acid, hydrochloric acid and methanol. The ratio of the products, formed in the parallel steps, was determined, and we also determined the total rate constant for the hydrolysis of chloroacetophos.

1. It has been shown that the 250–420°C fraction from the thermal cracking of semitar can be used in the production of carbon black stock by selective extraction. 2. Furfural is the most suitable extraction solvent. 3. It is recommended that the thermal-cracking residue should be used fully or partially in the production of carbon black stock.

1. It has been shown, that, in principle, high-quality starting material for carbon black manufacture can be produced from an appropriate mixture of heavy and polymeric gasoils produced in various types of catalytic cracking units, and from the residue left after distillation of the 270°C fraction from the appropriate mixture of light and heavy gasoils produced in units with a fluid catalyst bed. 2. Extracts from the starting materials mentioned meet all requirements imposed on a starting material for the production of active carbon blacks.

The cyclic sulfites of the 3α, 4α- and 3β,4α-caranediols were synthesized as mixtures of two isomers that differ in the relative position of the S=O and 10-CH3 groups.

1. The kinetics of hydrolysis of a series of alkyl-bis-(γ-chloropropyl)phosphinates were studied. 2. These esters hydrolyze faster in water, but many times slower in base, than the corresponding bis (chloromethyl)phosphinates. 3. The ratio of rate constants for esters of the two types decreases with increasing length and branching of the alcohol radical for base hydrolysis, but increases for water hydrolysis. This is consistent with the proposed intramolecular catalysis by chlorine in the γ-position, operative for the reaction in water.

We studied the kinetics of the alkaline and neutral aqueous hydrolysis of the ethyl ester of bis(chloromethyl) thiophosphinic acid. Replacement of the P=O group by P=S in ethylbis(chloromethyl)phosphinite increases the rate of the reaction with water and reduces that of the reaction with the OH− ion.

1. The possibility of obtaining carbon-black raw material from distillate coking fractions is determined by the nature of the raw materials going into the coking. 2. Extracts from distillate fractions obtained by the coking of crude oils, cracking residues, and their mixtures with extracts from the production of oil from low-sulfur petroleums, are a high-quality raw material for the production of carbon black. Analogous products from sulfur-bearing petroleums must be subjected to hydropurification before extraction, to obtain a low-sulfur carbon-black raw material. 3. Extracts of distillate fractions from the coking of tars from Koturtepinsk and Mangyshlak petroleums cannot be used as raw materials in the carbon black industry.