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The main methods of moisture protection of products made of quartz ceramics are described, the advantage of quartz ceramics modified by bulk impregnation with MFSS-8 solution is shown. Experimental data on the properties of modified quartz ceramics obtained with different types of impregnation are presented. Ill. 4. Ref. 5. Tab. 1.

Slip evacuation is shown for the first time to be applicable in the manufacture of large-size radio-technical parts from quartz ceramics. It was found that the evacuation of quartz glass based slip before molding ceramic blanks makes it possible to increase the density of the ceramic material by 0.01 g/cm3 and improve its uniformity by more than 30% and to reduce the number of cavities in parts made from quartz ceramic by removing air from the slip.

New labdanoid derivatives containing hydrophilic substituents (amino, methylamino) in the C-4 position were synthesized via selective transformations of lambertianic acid chloride. A one-pot method was proposed to prepare 16-formyllambertianic acid amide and included selective formylation of lambertianic acid by POCl3 in DMF followed by amidation by aqueous NH4OH. The molecular structure of the compound was studied by an X-ray crystal structure analysis. Analgesic activity in a chemical irritation model was found for newly synthesized 4-amino-18-nor-15,16-epoxylabda-8(17),13,14-triene and 4-(pyrrolidin-1-yl)-18-nor-15,16-epoxylabda-8(17),13,14-triene oxalates and 16-hydroxymethyl)lambertianic acid amide.

New derivatives of isopimaric acid at the carboxylic acid were prepared. Their analgesic activity was studied in models of visceral and thermal pain. Isopimaric acid amides with aminoethanol and (2R)-(hydroxymethyl)pyrrolidine groups exhibited statistically significant analgesic activity in acetic acid-induced writhing (5 and 25 mg/kg doses) and hot-plate tests (25 mg/kg dose) that was comparable to that of diclofenac sodium (10 mg/kg dose). The new agents were characterized by low (LD50 > 1250 mg/kg) in vivo toxicity. Molecular modeling of possible interaction of the most active compounds with transmembrane G-protein-binding cannabinoid receptor CB2 was performed.

An economic and mathematical model has been developed to determine the competitiveness of REMIX-A and -C uranium-plutonium fuel obtained by reprocessing spent fuel from thermal reactors. The presented model makes it possible to calculate the cost metrics of nuclear fuel components and the fuel component of the cost of NPP electricity as a function of the cost metrics of key process changeovers. It is shown that as the market quotations for natural uranium and separation work increase, REMIX fuel becomes more competitive and, more importantly, all the more significant, the lower the cost of reprocessing spent fuel. However, even with zero cost of reprocessing the gain from the introduction of REMIX fuel does not exceed 25%. At the same time, its use allows a 20-fold reduction in the mass of radioactive waste going to final disposal, 24% (REMIX-A) to 36% (REMIX-C) savings of natural uranium, and 8–18% of separation work (REMIX-A) as well as 18% (REMIX-A) to 40% (REMIX-C) reduction in the accumulation of depleted uranium hexafluoride.

A series of 16-arylisopimaranes has been synthesized by palladium-catalyzed arylation of the corresponding tricyclic diterpenoid isopimaric acid or its methyl ester in the presence of silver carbonate. No ligand was essential for the formation of new type optically active styrene derivatives. Good-to-excellent yields were obtained with good chemical tolerance. Silver carbonate enhanced the rate of the reaction. The use of cesium carbonate as the base requires an increase in reaction time and need for increasing amounts (2 mol%) of the palladium salt. The cross-coupling reaction proceeds with the formation of 16-arylisopimaranes with the (E)-type geometry of the double bond. Several transformations on the aryl substituent were carried out. The structure of target compounds was confirmed by X-ray diffraction study.

This paper reported creating the all-chromatographic technique for the recovery of americium radionuclides from solutions of the complex composition generated in the radiochemical industry. The technique was based entirely on the displacement complexing chromatography; neither additional precipitation nor extraction stages were necessary. The technology used the elution with DTPA and NTA-based solutions containing the citric acid additives and the sequential elution with these eluents, emphasizing the separation of americium from the heavy rare earth elements, lead, and cadmium. The complete separation of americium from lead and cadmium was a peculiar exercise; the elution order of lead and cadmium changed in the presence of the citric acid additives. The recovery and separation of americium from actual radioactive waste solutions of different origins demonstrated 96 and 99% chemical purity of the final product.

In this work, the chemical digestion conditions for spent KU-2 × 8 sulfocationites manufactured in Russia were investigated. It was shown that the complete oxidative digestion of the ionites could be performed in solutions of H2O2 and HNO3 in the presence of Fe3+ ions adsorbed on the resin as an oxidation catalyst. The total digestion time of the resin was studied as a function of the presence of the digestion catalysts, solid-to-liquid phase ratio, process temperature, Fe3+ ion content in the solid sulfocationite phase, and the divinylbenzene (DVB) cross-linking agent content of the ionite. A possibility for the removal of rare earth element (REE) and transplutonium element (TPE) radionuclides from the solution of the digested sulfocationite was shown by the sorption technique using the tetra-n-octyldiglycolamide (TODGA)-based sorbent.

Phlomisoic acid reacted with methyl-1-deoxy-2,3,4-tri-O-acetyl-1-bromo-α-D-glucopyranuronate to form the 18-O-β-D-(glucuronopyranoside)-6′-O-methyl ester of 15,16-epoxylabda-8(9),13,14-triene. Reductive amination of methyl 16-formyl-15,16-epoxylabda-8(9),13,14-trienoate or this β-D-glucuronopyranoside of 16-formyl-15,16-epoxylabda-8(9),13,14-triene by propargylamine in the presence of NaBH4 gave the corresponding 16-propargylaminomethyl-15,16-epoxylabda-8(9),13,14-trienes. Copper-catalyzed azide-alkyne cycloaddition of the new terpenoid alkynes and the propargylamide of phlomisoic acid with methyl 1-deoxy-2,3,4-tri-O-acetyl-1-azido-α-D-glucopyranuronate synthesized the corresponding labdanoid glucuronides and diglucuronide. Selective screening of the labdanoid triazolylglucuronides identified compounds with analgesic activity in chemical and thermal irritation tests.

The effect of the pH and rotational mixing time of slip on the likelihood of the appearance of cracked rejects was determined by means of statistical analysis of data on the preparation of slip from quartz glass and data on ceramic rejects. By means of data on the zeta-potential of slip particles and an examination of the scheme of physicochemical transformations of submicron particles of quartz glass and silica sol in the slip we were able to identify the intervals of optimal values of the pH and rotational mixing time of the slip.

The design and the preparation of a small library of optically active polyazamacrocyclic compounds with a furan bridge, connected by (4-(methylaminomethyl)-1,2,3-triazole) rings with methylene, ethyloxyethyl or ethylethoxyethyl units from natural labdanoid lambertianic acid is reported. The synthesis of the key 15,16-bis((tert-butoxycarbonyl(prop-2-ynyl)amino)methyl)labda-8(9),13,15-labdatriene from the plant diterpenoid lambertianic acid is also described. CuAAC reaction of this compounds with various diazides in the presence of Cu(II)/sodium ascorbate in methylene chloride/water reaction medium led to the mentioned chiral macrocyclic compounds with a furan bridge binding Zn2+ ions in solution.

The economic expediency of re-enrichment of depleted uranium with the possibility of subsequent disposal of secondary waste is evaluated. Three variants of bringing depleted uranium as a raw material into the production of natural-uranium equivalent and enrichment of uranium product are examined. Methods are proposed for evaluating the expediency of producing a natural-uranium equivalent from depleted uranium under different market conditions and in different operating regimes of the separation cascade as well as methods of evaluating the value of depleted uranium in the production of a natural-uranium equivalent and the production of enriched uranium product. It is shown that an effective method of bringing depleted uranium into enrichment is diversified production of enriched uranium product and not the production of a natural-uranium equivalent.

The effect of plasticizers based on sulfonated melamine formaldehyde (Melment F 15 G) and polycarboxylate (Melflux 5581 F, Sika ViscoCrete-G2) on the properties of molding plaster consisting of α-calcium sulfate hemihydrate was studied. The concentrations of additives that increase the strength in compression of molding plaster samples by factor of 1.5 – 2 were determined on the basis of the results of this work.

The formation of very fine SiO2 particles during milling of quartz glass in the fabrication of ceramic parts was investigated. A method for determining the quantitative content of very fine silica in slip based on quartz glass was developed and tested. The concentration of very fine SiO2 particles in different batches of slip was determined. The influence of the content of the colloidal component in slurry on the sintering of ceramic material was evaluated.

The synthesis and properties of tricyclic pimaranes containing a C-16 β-carboline are reported. A Pictet–Spengler reaction of methyl 15-oxo-16-formylisopimarate (prepared in situ from the 15-oxo-15,16-dihydroisopimarate) and tryptamine or tryptophan methyl ester in the presence of trifluoroacetic acid formed a mixture of terpenoid 1,2,3,4-tetrahydro-β-carbolines, 3,4-dihydro-β-carbolines, and β-carbolines. Tetrahydro- and dihydro-β-carbolines in CHCl3 were oxidized to the corresponding β-carbolines by treatment in air with basic Al2O3.

The synthesis and properties of tricyclic diterpenoids containing a C-4 functionalized oxazole ring are reported. The reaction of 4-[5-(bromomethyl)oxazol-2-yl]-18-norisopimarane with sodium azide in the presence of hydrated copper sulfate and sodium ascorbate in DMF gave the corresponding azide, from which new diterpenoid derivatives containing a 1H-substituted 1,2,3-triazol-4-yl substituent were synthesized. Reduction of the azide produced the terpenoid 5-aminomethyloxazole. Reaction of 4-[5-(bromomethyl)oxazol-2-yl]-18-norisopimarane with methyl esters of amino acids in DMF in the presence of potash synthesized compounds with oxazole C-5 amino-acid substituents. Cytotoxicity of the new isopimaric acid derivatives gainst CEM-13, MT-4, U-937, MCF-7, and MDA-MB-231 human tumor cells was studied.

An economics-mathematical model for performing analytical calculations of the present value of separative work for uranium isotopes in a separation plant currently being designed using gas centrifuge technology is examined. Analytical expressions are obtained for the present value of the separative work, the internal rate of return, and the payback period of the separation plant as a function of its main engineering and economics parameters – productivity (capacity), capital investment, and operating expenses. Calculations of these criteria for investment efficiency are presented for a wide range of initial data. It is shown that the calculation of the present value of separative work must be performed in a complex with other investment efficiency criteria in order to determine their optimal combination.

The conditions for oxidizing methyl isopimarate to the 15-oxo-15,16-dihydroisopimarate were studied. The latter was used for one-pot syntheses of 13-(oxazol-5-yl)-15,16-bisnorisopimarates that included formation of the 16-oxoaldehyde isopimarate and its condensation with α-amino acids. The structures of the synthesized compounds were confirmed by IR, UV, and NMR spectral data and an XSA.

It is shown that together with the reduced cost of electricity it is also necessary to examine other efficiency criteria for investments in NPP – the internal profitability norm and the discounted payback time of investments – and their impact on the primary profitability criterion of an NPP project – the pure discounted income. The analytical interconnection of the pure discounted income, internal profitability norm of a project, and the discounted payback time of investments, which is obtained using an exponential discounting function for the expected cash flows, is shown. The requirements of the engineering and economic parameters of NPP that make NPP competitive on the world market are formulated from an analysis of the interrelation of investment efficiency criteria. The NPP investment risk evaluated by the Monte Carlo method with prescribed uncertainty of prediction of cash flows during construction and operation of NPP is presented.

The paper considers the dispersion of charge carriers depending on the background noise and the electric field exposure. This dependence is obtained using the Lax equivalence theorem in terms of the step distribution of spectral density of extrinsic electronic defect states within the forbidden band of semiconductor. Instead of using quasi-Fermi levels, the paper describes the semiconductor density state under the background noise. This approach is based on ‘heating’ the semiconductor with background noise allowing to correctly detect the Fermi energy-level within the wide range of the power of background noise. It is observed that the dispersion/voltage dependence continuously grows and saturates, while the background noise shifts this dependence to the lower values of voltage. Based on the results, it is shown that the noise minimum of n-CdSe photoresistor under the background noise and electric field exposure cannot be explained only by the assumed step distribution of spectral density of extrinsic electronic defect states within the forbidden band of semiconductor.

(17R)-17,18-Dipropargyloxylabda-13,15-diene was synthesized and underwent Cu-catalyzed cycloaddition with 1,10-diazodecane or 1,2-bis(2-azidoethoxy)ethane to produce macroheterocycles of the furanolabdanoid decalin fragment. The macroheterocyclic labdanoids showed significant cytotoxicity in MEL-8, MT-4, and U-937 human tumor cell models.

Derivatives of natural diterpenoid methyl lambertianate containing propargyloxy substituents in 16,17-positions were obtained. CuAAC reaction of methyl 17-propargyloxy-16-[(prop-2-yn-1-yloxy)methyl]labdadienoate with various diazides in the presence of Cu(II)/sodium ascorbate in methylene chloride/water reaction medium gave chiral macrocyclic compounds connected on the 16 and 17-positions by 1,2,3-triazole rings with methylene, ethyloxyethyl or ethylethoxyethyl units. The obtained macrocyclic structures showed high selectivity and affinity for Hg2+ ion by the 1,2,3-triazole rings.

New isopimaric acid derivatives containing amines and methyl esters of α-, β-, and ω-amino acids were prepared. Conditions were found for cyclic isomerisation of isopimaric acid propargylamide into 2-(dodecahydrophenanthren-1-yl)-5-methyloxazole or 2-(dodecahydrophenanthren-1-yl)-5-methylene-4,5-dihydrooxazole. The latter was selectively modified by adding the methyl ester of (2-methylamino)butanoic acid at the oxazole C-5 position.

Structures of plant furanolabdanoids and synthetic schemes for a series of furanolabdanoids (coronarins A and E, hedychenone, acuminolide and 17-O-acetylacuminolide) from the available diterpenoids sclareol and larixol were reviewed. Attention was focused on transformations of available furanolabdanoids. Data on the biological activity of native metabolites and their synthetic derivatives were presented.

Methods were proposed for preparing 15,16-dihydroisopimaric acid and its methyl ester. Oxidation of methyl dihydroisopimarate through the action of 3-chloroperbenzoic acid occurred with formation of 7,8-epoxy-derivatives and 7α-hydroxydihydrosandaracopimarate. The latter in addition to 7-oxotetrahydroisopimarate were formed through the action of t-butylhydroperoxide in the presence of MoCl5. Oxidation of dihydroisopimaric acid or the ester by selenium dioxide in dioxane gave the corresponding 14α-hydroxy-derivatives. Pyridinium chlorochromate transformed 14α-hydroxydihydroisopimarate into a mixture of methyl esters of 7α-hydroxy-8,14-epoxyisopimaric, 7-oxo-8,14-epoxyisopimaric, 7-oxo-14-hydroxyisopimaric, and 7α-hydroxysandaracopimaric acids. Oximation of methyl 7-oxotetrahydroisopimarate by hydroxylamine hydrochloride in MeOH in the presence of NaOAc gave a mixture of the corresponding (Z)- and (E)-oximes. Beckmann rearrangement of the 7-(E)-oxime of methyl tetrahydroisopimarate through the action of thionylchloride led to tetradecahydrodibenzo[b,d]azepine.

The possibility of using lithium aluminosilicate glass crystallized in a low-temperature furnace (up to 1000°C) for manufacturing components for radio engineering purposes is studied.

16-(1-R-1,2,3-Triazol-4-ylethyl)-, 16-(1-R-1,2,3-triazol-4-ylmethoxymethyl)-, and 16-{2-(1-R-1,2,3-triazol-4-yl)-1-[(1-R-1,2,3-triazol-4-ylmethoxy)ethyl]}-substituted derivatives of methyl lambertianate were synthesized by 1,3-cycloaddition of labdanoid alkynes with azides. The compounds obtained possess considerable cytotoxicity toward the human tumor cell lines CEM-13, MT-4, and U-937. The most active compound, methyl 16-(2-{2-[(1-benzyl-1H-1,2,3-triazol-4-yl)acetyl]furan-3-yl}ethyl)lambertianate, was found to inhibit the viability of the tumor cells by 50% (CCID50) in the concentration of 7–12 μmol L−1.

Allylic oxidation of phlomisoic acid and its methyl ester by selenium dioxide occurred stereoselectively to form 7α-hydroxy derivatives of labdanoids, which were oxidized by active manganese dioxide to 7-ketofuranolabdanoids. Oximation of the last by hydroxylamine hydrochloride in MeOH in the presence of NaOAc gave pure (E)-ketooximes. Beckmann rearrangement of 7-ketooximes of phlomisoic acid and its methyl ester occurred with formation of the corresponding octahydro-1 H-benzoazepines.

Contemporary machining methods for ceramic materials are analyzed. Laser, hydroabrasive and high-speed machining are considered. The possibility of using these methods for machining large complexly-shaped ceramic objects having a double surface curvature is evaluated.

The mechanism of structure formation and phases formed in the course of synthesis of a glass ceramic lithium aluminosilicate system are analyzed.

Results are presented for a study of functional coating application, for example with increased blackness coefficient, on ceramic and glass ceramic materials. Various methods for coating application used currently are considered. A coating is proposed based on methyl phenyl spirocyloxane polymer (product MFSS-8).

The oxidation of n-heptadecane was studied at various partial pressures of oxygen in an oxygen-argon mixture from 100 to 10% and various initiation rates Wi in the range (1–5)·10−6 mol L−1 s−1 at 413 K. The kinetic curves of oxygen uptake and hydroperoxide buildup were obtained under the indicated conditions. The observed features of n-heptadecane oxidation at low concentrations of oxygen may qualitatively be explained and quantitatively described if the oxidation scheme takes into account the cross termination of alkyl and peroxyl radicals R · + RO2 · \(\underrightarrow {k_5 }\) ROOR along with the square termination of peroxyl radicals. A method for determination of the corresponding kinetic parameter by the dependence of the initial oxidation rate on the partial oxygen pressure was proposed. A method for identification of the key reactions and determination of the kinetic parameters by the kinetics of oxygen uptake at lowered oxygen concentrations was developed. The kinetic model of the process was obtained, which quantitatively describes the kinetic curves of oxygen uptake and hydroperoxide buildup at the initial steps of initiated oxidation of n-heptadecane.

Existing ceramic technology is analyzed for producing high-speed zenith guided rocket antenna radomes made of glass ceramic OTM-357. This is the main production operations, and their disadvantages are noted. Prospects are considered for modernizing the technology.

Existing technology for manufacturing high-speed zenith guided rocket radomes from quartz and glass ceramic materials is analyzed. The main production operations are provided for this technology, their disadvantages are demonstrated, and ways of improving the quality of components are considered.

Three main materials are considered: sitall, high-alumina and quartz ceramic, currently used for creating rocket radomes. Physicotechnical properties of the materials are provided: thermal shock resistance, thermal conductivity, dielectric permittivity, dielectric loss tangent, and also stability during component operation.

Radioparent materials that exist in the world, that may be used in the production of the radome of high-speed zenith guided rocket fairings are analyzed. The main physicotechnical indices are provided for these materials and the future for their application in radome production is indicated.

The effect is considered of such operating properties as the design of a molding unit and the method of drying gypsum molds, on the life of the forming surface of molding units. Avoidance of the disadvantages revealed combined with results obtained in part 1 (E. I. Sudal’tsev, D. V. Kharitonov, and A. A. Anashkina, “Increase in the service life of forming surfaces of molding units. Part 1. Study of the improvement of molding unit forming surface material quality,” Novye Ogneupory, No. 2, 30 - 38 (2010).) of this work make it possible to increase the service life of molds by more than a factor of three

Materials are reviewed that are used in manufacturing the forming surfaces of molding units. Choice of the optimum water and gypsum ratio for a gypsum paste is provided and methods are considered for improving gypsum mold quality.

A method for preparing 15,16-epoxylabda-8(9),13(16),14-trien-18-oic (phlomisoic) acid was proposed. Its structure was confirmed by an XSA. N-containing derivatives of phlomisoic acid that contained amines, hydrazides, and methyl esters of amino acids on the C-18 atom in addition to (2-oxo-2-aminoacetyl)-substituted derivatives of the C-16 methyl ester of phlomisoic acid were prepared.

Methods are surveyed for centering molding assemblies as used to mold large ceramic blanks from aqueous slip. Existing and promising future methods of centering are examined, with emphasis on their advantages and shortcomings. The analysis shows that video centering is the most promising method.

It is shown that one way of synthesizing new composite materials for producing antenna fairings may be the method of molding billets from mixed suspensions of lithium aluminosilicate and quartz glasses followed by sintering to the required level of physicotechnical properties. These studies make it possible to isolate a region of SiO 2 content (5-40%) within whose limits it is possible to prepare materials with quite high strength, i.e. from 75 to 120 MPa, and a broad spectrum of dielectric properties: a dielectric permittivity from 5.0 to 6.7, and a dielectric loss tangent from 0.009 to 0.007. It is established that the most uniform structure occurs for specimens molded from slips with a moderately fine SiO 2 addition (5-7% content of 63-500 μm particles) that promotes the minimum amount of open porosity in billets.

The distribution of the gamma ray dose rate on a temporary storage site for solid radioactive wastes is measured in the town of Gremikha by a remote-control method using a Cartogram gamma-viewer. The main sources of the gamma radiation on the site and the dose rate of the radiation before and after measures are taken to improve the radiation conditions on the site are determined. This has made it possible to perform a comparative qualitative and quantitative analysis of the effectiveness of the measures taken and to ensure support for further planning of the rehabilitation of the territory.

A method and a device are proposed providing continuous monitoring for assembly of ceramic billets. The suggested system makes it possible to monitor objectively fulfilment of the requirements of a production process that ultimately reduces scrap in preparing ceramic billets from aqueous slips.

An integrated study has been made on searching for new mold set designs and technological solutions to eliminate the effect of nonuniform buildup of ceramic preforms on the rejection rate. New molding equipment is proposed equipped with a molding monitoring system and an innovative centering device, which makes it possible to decrease the rejection rate in molding.

Basic methods for manufacture of large-sized complex-shaped ceramic components by casting from aqueous slips — cryogenic, centrifugal, electrophoretic, etc. — are considered. Of these, the slip casting in porous molds is advantageous in terms of cost and technological simplicity. To achieve further progress, attention should be focused on the development of adequate molding equipment to minimize the rejection rate of finished product.

Working materials for mold sets used in slip casting technology are reviewed. Benefits and shortcomings of the materials are discussed and routes towards improving their performance are suggested.