Preview

Fine Chemical Technologies

Advanced search
Vol 9, No 6 (2014)
View or download the full issue PDF (Russian)
7-10 41
Abstract
170th Anniversary of ruthenium discovery in Russia

CHEMISTRY AND TECHNOLOGY OF MEDICINAL COMPOUNDS AND BIOLOGICALLY ACTIVE SUBSTANCES

11-25 72
Abstract
Although anthracycline antibiotics are widely used in the treatment of cancer, their use is limited due to severe side-effects, including irreversible cardiotoxicity and multi-drug resistance of tumor cells. One of the promising approaches towards “ideal” anthracycline is the creation of anthracycline-based prodrugs, i.e. compounds that are less active than the parent drug (or inactive) and are converted in its active form through a metabolic process. The main goal of the development of anthracycline prodrugs is to increase the selectivity of the drug (doxorubicin or daunorubicin) towards tumor cells with simultaneous decrease in toxicity to normal cells. With this aim different types of anthracycline prodrugs were designed targeting such specific characteristics of tumor cells as lower pH and oxygenation level in comparison with normal cells, higher content of different enzymes etc. Also two-stage “enzyme-prodrug” strategies which include the selective introduction of the enzyme into the tumor cells on the first step and administration of the prodrug which is the substrate for this enzyme on the second step are developed. These strategies are classified depending on the method of “introduction” of the enzyme into tumor cells: antibody-directed enzyme prodrug therapy (ADEPT), virus-directed enzyme prodrug therapy (VDEPT) and genedirected enzyme prodrug therapy (GDEPT). The review covers recent achievements in the field of creation of different types of anthracycline prodrugs
26-41 69
Abstract
Based on the aggregate results from several different studies, this article will provide readers a survey view about the ability to drug delivery one of the most typical nano structures – liposome and the use of this structure for various therapeutic purposes, including anticancer therapy, antibacterial therapy and gene therapy.
42-46 50
Abstract
The report investigates the temperature dependence of the heat capacity and the rate at which heat capacity changes for eleven unfilled vulcanizates for all-purpose and special-purpose rubber in the temperature range between 133K and 373K. Basic numerical characteristics of integral and differential curves have been established and correlations between them have been examined. The differential equation of the process has been obtained

THEORETICAL BASES OF CHEMICAL TECHNOLOGY

47-54 45
Abstract
For linear partial differential equations there are various techniques for reducing the partial differential equations (PDE) to the ordinary differential equations (ODE) or at least to equations in a smaller number of independent variables. These include various integral transforms and eigenfunction expansions. Usually such techniques are not applicable in dealing with nonlinear partial differential equations. From this point of view the presented approach is much more interesting. It identifies equations for which the solution depends on certain groupings of the independent variables rather than depending on each of the independent variables separately. The name of these solutions, self-similar, comes from the fact that the spatial distribution of the characteristics of motion remains similar to itself at all times during the motion. Roughly speaking, the idea is to look whether the solution of a problem u(x, y) can be collapsed in a function u(x, y) = U(y / f (x)). The function f (x) may be found by substitution in the PDE, in order to obtain an ODE for U . Self-similar solutions of the non-local equations describing the explosion with the spherical symmetry are investigated for the case of the astrophysical applications. Namely, in the quasi-stationary Hubble regime only the implicit dependence on time for the unknown values exists. It means that for the intermediate (Hubble) regime the complicated PDE set can be transformed in the set ODE. This possibility can be realized also in the case if the self-similar solutions exist. The mentioned self-similar solutions are found for Hubble regime.
55-61 63
Abstract
Ethane conversion under the conditions of oxidative coupling of methane (OCM) has been investigated. In an empty reactor above 800°C, ethane oxidation occurs at a higher rate, and its main product is carbon monoxide. In the presence of NaWMn/SiO2 catalyst the rate of ethane oxidation noticeably decreases, and ethylene becomes the main product of the reaction. Thus, it is demonstrated that the catalyst, on one hand, is an effective inhibitor of unselective gas phase oxidation processes, and on the other hand, it substantially changes the hydrocarbon conversion routes. The complex kinetic conjugation during ethane oxidation in the presence of an excess of methane in the reaction mixture is observed. In the case of homogeneous ethane oxidation, methane acts as the gas-phase oxidation inhibitor, presumably by reducing chain reactions contribution to the overall reaction rate. On the contrary, during the oxidation of a methane-ethane mixture over NaWMn/SiO2 catalyst, a strong mutual effect of the hydrocarbon components on the rate and direction of their transformation is observed.
62-68 83
Abstract
The mathematical model for system, containing ethanol, chloroform and 1-ethyl-3-methylimidazoliumtrifluorosulphonate is obtained. NRTL binary parametres are evaluated and vapor-liquid equilibrium is calculated. The possibility of separation ethanol-chloroform mixture with ionic liquid as extractive agent is evaluated.
69-74 52
Abstract
On the assumption of the initial Gaussian distribution of the inter-radical distances the dependence of the radical combination probability in a solvent cage on the viscosity and temperature was derived. The dependence describes the published data correctly and may be used for the initial inter-radical distances estimation in different radical pairs.
75-80 41
Abstract
The effect of support on the activation parameters of C-C bond cleavage in a propanoic acid molecule was studied with DFT-PBE approach using the model of Pd9 cluster supported on (Al2O3)4 and (Al2O3)4(OH)2. Free activation energy is higher for Pd9/Al8O12 and Pd9/Al8O12(OH)2 (135-146 kJ∙mol-1 ) comparing to that of isolated Pd9 clusters (115-125 kJ∙mol-1 ). The effect of support is stronger (up to 31 kJ∙mol-1 ) for those structures, where the distance between Al8O12 and reactive palladium atoms is shorter. The energy of interaction between Pd9 and “dry” alumina compared to hydroxylated one (Al2O3)4(OH)2 is about two times less: 253-351 and 560-579 kJ∙mol-1 , respectively. The difference in energies is related to dependence of the energy of optimized structures on initial Pd9 location above alumina support. Despite that, activation parameters (Δ≠ G623) of C-C cleavage step differ slightly for (Al2O3)4 and (Al2O3)4(OH)2, from 1.3 to 5.6 kJ∙mol-1 . For all the models considered a carbon-carbon bond cleavage in a molecule of propanoic acid occurs as a threecentered interaction, viz. with participation of single Pd atom

CHEMISTRY AND TECHNOLOGY OF ORGANIC SUBSTANCES

81-86 52
Abstract
γ-Trifluoropropylmethyldichlorosilane interaction with ethyl- and phenylchlorosilanes in aluminum chloride presence was studied. It is demonstrated that besides expected exchange reactions of Cl↔F at silicon, exchange reactions proceed with the participation of γ-trifluoropropyl substituent resulting in the formation of a few new unsaturated allyl-type compounds. There is no intermolecular exchange of organic substituents. It is found that chlorine atoms, which are in γ-position towards silicon in a hydrocarbon chain, are active in dehydrochlorination reactions in aluminum chloride presence in contrast to chlorine atoms in α- and β-positions.Tetraethylsilane has been found to be passive in the studied reactions in contrast to ethylchlorosilanes. A scheme explaining the obtained results is proposed, and quantum-chemical calculations of the basic reactions have been made.
87-94 53
Abstract
The present paper discusses the results of experiments on the preparation of sulfuric acid inverse emulsions in the media of different liquid alkanes. Attention was put on the influence of system composition on the performance emulsions stabilized by a cationic surfactant – dialkyldimethylammonium chloride and a series of aliphatic alcohols (hexanol, ethylhexyl alcohol etc) used as co-surfactants. The phase diagram was obtained, and the optimal composition was found. Besides, estimation of particle size distribution in the systems was provided by dynamic light scattering technique.

CHEMISTRY AND TECHNOLOGY OF INORGANIC MATERIALS

95-98 76
Abstract
The reaction of dissolution of solid PdCl2 in water-chloride media at room temperature was studied. It was established that the reaction proceeds via a mechanism of topochemical reaction. With the ionic strength fixed, the reaction rate constant is shown to depend on the chloride ion concentration with n = -2, thus confirming that this reaction goes through the formation of hydroxyl and aquachloride complexes of palladium. At low chlorides background С (NaCl) < 0.3 M, and the topochemical nature of the reaction is mainly determined by hydroxide concentration in equilibrium with aquachloride complexes of palladium. The nature and rate of topochemical reaction is determined by concentration of NaCl. With decreasing the concentration of chloride ion from 1 M to 0.2 M reaction proceeds from kinetic to diffusion region.
99-102 53
Abstract
The article suggests a mechanism of pyrocarbon formation on the soot surface and explains the reason of specific surface polyextremity changing. It is possible only due to heterogeneity of pyrocarbon deposition process. It is assumed that hydrocarbon products adsorption from a gas phase takes place on the surface active centers which are formed on the boundaries of contact of crystallites and places of heteroatoms localization. Experimental results confirming these assumptions are given. It is shown that the length of the boundaries of contact of crystallites will influence the intensity change of specific surface (H-factor) and also on the rate of the chemical reaction
103-109 47
Abstract
In the article the environmental management system at the enterprises of the petrochemical complexes and ecoanalytical laboratory activities as a part of it are considered. In addition to its direct responsibilities for the analysis of the test material the activities of eco-analytical laboratory include responsibilities to ensure the correct and timely document and maintain continuous access to the information of all performers involved in the process. The reader is invited to refer to the approaches to the formation and construction of information-analytical systems by the example of developing systems for data collection and processing for environment control laboratories. The purposes and tasks of developing systems were identified during the analysis of the informatization object. Algorithms for information processing were established, and the management system of the eco-analysis laboratory information is presented in a separate form as components with the establishment of areas of responsibility. In the findings the expected results from the information-analytical system in terms of growth needs of environmental management effectiveness are described.


ISSN 2410-6593 (Print)
ISSN 2686-7575 (Online)