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The heroine of Pushkin’s novel in verse Eugene Onegin, Tatyana became the prototype of a brilliant series of female characters in 19th-century Russian literature. Various interpretations of her image can be grouped around an idealizing pole (Dostoevsky: “apotheosis of the Russian woman”) and a realistic one (Belinsky regarding the figure in her evolution from an ardent but naive provincial damsel to a dame of the Muscovite high society). Chekhov narrates in his short story После театра [After the theatre] about a 16-year-old girl Nadya, who, having returned home from the performance of the opera Eugene Onegin, and effected by Tatyana’s writing to Onegin, starts to write a letter to a young man, who, as she thinks, is in love with her; then, suddenly she decides to write to another young man who also pays court to her. At the same time, she experiences rapid changes of her mood: she bursts out now into tears, now into laughter without any real reason; and gradually, she becomes filled with an incomprehensible feeling of joy. Chekhov, who was not only a sensitive writer but also a sharp-sighted physician, reliably describes in Nadya’s behaviour the psycho-somatic symptoms of early puberty when the estrogenic hormones come into action. The undercurrent of this story is apparently a delicate ironical hint at Tatyana’s juvenile rapture over Onegin. Chekhov does not deglorify Pushkin’s heroine, he just supplements her realistic interpretation with the psycho-physiological aspect of the formation of her personality.

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The paper presents the results of a study of metaphorical vocabulary with the meaning of assessment of social change. The analysis involves common Russian vocabulary as well as the material of Russian dialects. Previously unpublished expeditionary records of dialect speech are introduced into academic discussion. Special attention is paid to the onomasiological analysis of linguistic facts. Four groups of motives are revealed: the motives of destruction (loosening, turning inside out, and death); spatially dynamic motives (moving away and disappearance); the motives of qualitative changes (the loss of one’s own properties and status, the acquisition of similarity with representatives of a foreign nation, the acquisition of worse properties, cooling down); and the motives of confusion (mixing of different cultures and disorientation). It is shown that the bearers of traditional folk culture tend to evaluate the changes of any kind as undesirable. A disapproving assessment of social change is due to the orientation of traditional culture toward strict adherence to customs.

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Reaction Kinetics, Mechanisms and Catalysis
Authors:
Alexander Khassin
,
Georgiy Filonenko
,
Tatyana Minyukova
,
Irina Molina
,
Lyudmila Plyasova
,
Tatyana Larina
, and
Vladimir Anufrienko

Abstract

The anionic composition, structural parameters, optical properties and reduction behavior of Cu–MgO solid solution in hydrogen dramatically change after exposure to air. The air-exposed Cu–Mg oxide contains a lot of CO3 2− and OH anions. Its reduction proceeds via two stages: (1) diffusion of Cu2+ to the surface and (2) chemical interaction of Cu2+ with hydrogen. The effective activation energy gradually increases from that of the chemical step (65 kJ/mol) to that of the transport step of Cu2+ diffusion (130 kJ/mol). This behavior follows the “compensation effect”, which is close to those reported earlier for CuO reduction. On the contrary, reduction of Cu2+ from the Cu–Mg oxide sample, which was not exposed to air after thermal pretreatment in the inert gas, proceeds in one step at 120–160 °C with the effective activation energy of 19 kJ/mol, which is manifold less than the reported effective activation energies for various Cu-oxide systems. Water molecules eliminate from the sample slowly along with further heating up to 450 °C.

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Polymorphism of paracetamol

Relative stability of the monoclinic and orthorhombic phase revisited by sublimation and solution calorimetry

Journal of Thermal Analysis and Calorimetry
Authors:
G. Perlovich
,
Tatyana Volkova
, and
Annette Bauer-Brandl

Abstract  

The thermodynamic relationship between crystal modifications of paracetamol was studied by alternative methods. Temperature dependence of saturated vapor pressure for polymorphic modifications of the drug paracetamol (acetaminophen) was mea sured and thermodynamic functions of the sublimation process calculated. Solution calorimetry was carried out for the two modifications in the same solvent. Thermodynamic parameters for sublimation for form I (monoclinic) were found: ΔG sub 298=60.0 kJ mol−1; ΔH sub 298=117.9�0.7 kJ mol−1; ΔS sub 298=190�2 J mol−1 K−1. For the orthorhombic modification (form II), the saturated vapor pressure could only be studied at 391 K. Phase transition enthalpy at 298 K, ΔH tr 298(I→II)=2.0�0.4 kJ mol−1, was derived as the difference between the solution enthalpies of the noted polymorphs in the same solution (methanol). Based on ΔH tr 298 (I→II), differences between temperature dependencies of heat capacities of both modifications and the vapor pressure value of form II at 391 K, the temperature dependence of saturated vapor pressure and thermodynamic sublimation parameters for modification II were also estimated (ΔG sub 298=56.1 kJ mol−1; ΔH sub 298=115.9�0.9 kJ mol−1; ΔS sub 298=200�3 J mol−1 K−1). The results indicate that the modifications are monotropically related, which is in contrast to findings recently reported found by classical thermochemical methods.

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Abstract

The effect of potassium additive on the catalytic activity of nickel–molybdenum alumina-supported systems has been studied by varying the molybdenum content within 5–18 mass% MoO3, reaction temperature from 180 to 400 (500)°C, and steam to gas ratio of 0.3, 0.7, and 1. It has been established that potassium reduces the activity of one-component Mo-containing samples, while, independent of molybdenum loading, nickel promotes activity within the whole temperature range studied and extends the temperature range of catalytic activity by about 70°C to lower reaction temperatures. A symbatic or additive, or antibatic catalytic behavior was observed with NiMo-containing samples depending on the atomic Ni/Mo ratio and temperature range. Potassium, being a third component in tri-component KNiMo-containing samples, enhances the water–gas shift (WGS) activity depending on the atomic K/(Ni + Mo) ratio. The activity approaches the equilibrium conversion degree in the interval of 320–500 °C. A decrease in the specific surface area of calcined and tested samples relative to the bare support shows close values indicating that the overall dispersion of the species is not changed during the catalytic test. Close examination indicated that the sample containing K2O, NiO, and MoO3 of 4.9, 2.5, and 12.7 mass%, respectively, was found to be the most suitable catalyst for water–gas shift reaction with sulfur containing feed since it attains equilibrium conversion even at 300 °C, and at a low steam to gas ratio of 0.3 atm. This catalyst demonstrates a stable and reproducible catalytic activity as inlet gas loading is increased.

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Abstract

Myxobolus talievi Dogiel, 1957 was originally described from the eyes, skeletal muscles and body cavity of endemic cottoid fish from Lake Baikal. In the present study, we supply new information on the myxospore morphology and histopathology of M. talievi; furthermore, we complete the original species description by Dogiel and Bogolepova (1957) with 18S ribosomal DNA (rDNA) sequence data. Histopathological analysis showed that the plasmodium was encapsulated by a thin layer of connective tissue and located in the intermuscular connective tissue among muscle cells. No inflammation was observed. Phylogenetic analysis revealed that M. talievi clustered with Myxobolus sp. 2 (NCBI Acc. No. U13830), an unidentified Myxobolus species from cottoid fish studied by Smothers et al. (1994), and located in the sister clade of Myxobolus spp. developing spores in the nerves of salmonids.

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Abstract  

The World Health Organization states that envenomation is responsible for a high number of deaths per year, especially in equatorial areas. The only effective specific treatment is the use of hyperimmune serum (antivenom). In Brazil, Crioula breed horses are used for antivenom production, with great importance in the maintenance of public health programs. A strict biochemical and metabolic control is required to attain specificity in antiserum. Inorganic elements represent only a small fraction of whole blood. Nonetheless, they play important roles in mammalian metabolism, being responsible for controlling enzymatic reactions, respiratory and cardiac functions and ageing. In this work, whole blood samples from Crioula breed horses were analyzed by EDXRF technique. The reference interval values were determined for the elements Na (1955–2013 μg g−1), Mg (51–75 μg g−1), P (523–555 μg g−1), S (1628–1730 μg g−1), Cl (2388–2574 μg g−1), K (1649–1852 μg g−1), Ca (202–213 μg g−1), Cu (4.1–4.5 μg g−1) and Zn (2.4–2.8 μg g−1) and a comparative study with NAA results was outlined. The samples were obtained from Instituto Butantan. Both techniques showed to be appropriate for whole blood sample analyses and offer a new perspective in Veterinary Medicine.

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Abstract

The behavior in aqueous solutions of the two types of layered perovskite-like structures, NaLnTiO4 titanates (Ln = Nd, La) belonging to the family of Ruddlesden–Popper phases and ANdTa2O7 tantalates (A = Na, Cs, H) belonging to the family of Dion–Jacobson phases, has been studied by means of thermogravimetric analysis and powder X-ray diffraction. In the case of NaLnTiO4 compounds, the substitution of protons for sodium cations and the water intercalation into the interlayer space of the crystal structure were observed and proton-containing layered oxides with general formula H x Na1−x LnTiO4·yH2O (0.63 < x < 1, 0 < y < 0.74) have been obtained. Investigation on the hydration in layered tantalates ANdTa2O7 (A = H, Na, Cs) showed that NaNdTa2O7 and HNdTa2O7 form compounds intercalated by water molecules. Two steps of water intercalation were observed for NaNdTa2O7 and HNdTa2O7. Stable hydrated compounds HNdTa2O7·0.84H2O, NaNdTa2O7·0.60H2O, and NaNdTa2O7·1.35H2O were synthesized.

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Reaction Kinetics, Mechanisms and Catalysis
Authors:
Olga Yugay
,
Tatyana Mikhailovskaya
,
Lyudmila Saurambaeva
,
Dauren Sembaev
, and
Pavel Vorobiov

Abstract

The effect of ZrO2 and ZrV2O7 on the polymorphic transformation of anatase to rutile in the TiO2–V2O5, TiO2–ZrO2, TiO2–ZrV2O7, and V2O5–TiO2–ZrO2 systems has been investigated. It is shown that the temperature and duration of the heat treatment influence on the anatase stability in the investigated binary and ternary systems. It is established that V2O5 and ZrV2O7 accelerate the polymorphic transformation of anatase to rutile, but ZrO2 inhibits the phase change. Taking into account the ratio between V2O5, ZrO2, and ZrV2O7, formed in the ternary system, it is possible to maintain a definite quantity of anatase in a catalyst system. This permits one to influence the activity and selectivity of the modified vanadium oxide catalysts in the oxidation and ammoxidation of alkylbenzenes and alkylpyridines.

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Journal of Thermal Analysis and Calorimetry
Authors:
Y. Rubtsov
,
A. Kazakov
,
V. Nedelko
,
Al. Shastin
,
Tatyana Larikova
,
Tamara Sorokina
, and
B. Korsounskii

Abstract  

The thermal stability of the ammonium nitrate (AN)/sodium salt of 1,3-dichlor-2,4,6-trioxo-1,3,5-triazacyclohexane (DC) composition has been studied. The factors of influence on the rates of reactions in the composition, namely, a water content, composition wetting methods, a dispersion of composition components, sample mass values, have been examined. The water presence in the composition reduces its thermal stability. The mechanism includes the partial dissociation of AN to HNO3 and NH3 and the hydrolysis of DC with the formation of some unstable Cl-containing compounds (chloramines, nitrogen chloride). The reaction of ammonium cation with active chlorine has been found to give rise to the explosion of the AN/DC composition. Such a situation is typical for other ammonium salt/DC compositions.

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