Thermodesorption investigation of catalytic systems

Conclusions Schemes of thermodesorption apparatuses and systems of experiments yielding information on the state of substances on the surface of catalysts and adsorbents, the activation energies, forms of adsorption, and composition of the desorption phase were described.For communications 1–4, see [6–9], respectively.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1461–1467, July, 1968.     

Some components of the seed oil ofMalva sylvestris

The lipid composition of the free fatty acids of the seed oil ofMalva sylvestris from the Ukrainian flora has been studied by chromato-mass spectrometry. The fatty acid composition was represented by 20 compounds, among which malvic and sterculic acids were detected. The presence of terpineols and retinol has been shown.Zaporozh'e Medical Institute. Translated from Khimiya Prirodnykh Soedenii, No. 3, pp. 322–325, May–June, 1994.     

Lipids ofOriganum tytthanthum

The composition of lipids and fatty acids from the above-ground part ofOriganum tytthanthum Gontsch. (Lamiaceae) is studied. Lipids from the air-dried plant material are enriched in glycolipids, essential fatty acids, and biologically active lipophilic substances. The free fatty acids include 15-methylhexadecanoic acid (0.5 % by GLC).Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 100–102, March–April, 2000.     

Amino acid composition of fruit in the manufacture of sedimentation-stabilized dispersed products

Information is given on the total amino acid composition and the free amino acids of pears (Pyrus communis L), squashes (Cucurbita pepo L), grapefruits (Citrus paradisi L) and apples (Malus sylvestris Mill.). It has been established that during the dispersion of the fruits in the manufacture of sedimentation-stabilized products that the total qualitative and quantitative amino acid compositions scarcely change but the concentration of free amino acids rises by 14.5–45.1% on the total amount of free amino acids in the initial material. The causes of the rise in the level of free amino acids are discussed.Odessa State Academy of Food Technology, fax (0482) 25 32 84. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 234–238, March–April, 1999.     

Lipids of microalgae. I. Lipids and a protein hydrolysate fromMonochrysis lutheri

The class composition and the total fatty acid composition of the readily- and difficulty-extractable lipids and the amino acid composition of a protein hydrolysate of the dry biomass from the golden-yellow microalgaMonochrysis lutheri have been determined for the first time. It has been established that the difficulty-extractable lipids differ sharply from the readily extractable lipids in the composition of the neutral and glycolipid components and also in that of the fatty acids; 27% of the weight of the fatty acids of the latter is composed of the 20:4 and 20:5 species. The protein hydrolysate ofM. lutheri contains almost the whole set of essential fatty acids.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbekistan Republic, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 507–511, July–August, 1993.     

Lipids ofPhellodendron lavalei seeds

The chemical composition of neutral lipids and phospholipids from seeds ofPhellodendron lavalei cork is studied. Characteristic features of the fine structure of the separate classes are found. Significant quantities of eicosatrienoic acid and neutral lipids are found. The polar lipids are biologically active.Deceased.I. G. Kutateladze Institute of Pharmacochemistry, Academy of Sciences of Georgia, Tbilisi, fax (99532) 25 00 26. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 220–222, May–June, 2000.     

Chemical characteristics of the septa of the fruit ofJuglans regia

The qualitative composition of the lipids, the triacylglyceride content, and the fatty acid composition of the septa of the fruit of Persian walnutJuglans regia have been determined. The phenol fraction is represented in the form of phenolic carboxylic acids, phenolic aldehydes, catechins, proanthocyanidins, and oligomeric and polymeric phenolic compounds, including lignin. Polysaccharides are represented mainly in the form of xylan and glucan.Scientific Research Institute of Horticulture, Viticulture, and Wine-Making of the Georgian Academy of Agricultural Sciences, 6 Gelovani pr., Tbilisi 380015. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 161–164, March–April, 1998.     

Effect of concentration of complexing agent on selectivity of the chromatographic phase

Conclusion The selectivity of the phase depends on the concentration of the metal salt and the basicity of the phase, in which connection the change in the selectivity is maximum for weakly basic phases with a high content of the metal salt.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 443–445, February, 1972.     

Transformations of hetarylideneoxazolones

Hetarylideneoxazolones are converted to hetarylideneamino acid esters by methanolysis in the presence of sodium. Alkaline hydrolysis in aqueous alcohol gives the corresponding amino acids. Hydrazinolysis of pyranylideneoxazolone gives pyranylideneamino acid hydrazide. Complete hydrolysis of oxazolone gives formylpyran, the methylation of which gives the methoxymethylpyrylium salt. Benzamidomethyl-substituted pyrylium salts were obtained by treatment of the hetarylideneamino acids with perchloric acid.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 757–763, June, 1976.     

Lipids of the seeds ofSecurinega suffruticosa

The lipid composition of the seeds ofSecurinega suffruticosa (Euphorbiaceae) has been studied, and eight classes of lipids have been identified with a predominance of triacylglycerols; the fatty acid compositions and structures of the triacylglycerols have been determined. Among the hydroxy acids of the hydroxyacylglycerols 13 components belonging to saturated, monoenic, and dienic acids of the C₁₇, C₁₈, and C₂₀ series have been identified; 12-hydroxyheptadecanoic and 12-hydroxyeicosanoic acids are new.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 277–281, May–June, 1986.     

Variation in the sorption energy of esters ofn-perfluoroalkanoic acids on chromatographic phases of different polarity

The contributions of methylene and difluoromethylene units of six homologous and six pseudohomologous series of esters ofn-perfluoroalkanoic acids to the differential molar free energy, enthalpy, and entropy of sorption on stationary phases of different polarities in glass capillary columns under isothermal conditions were calculated. The features observed characterize the peculiarities of the sorption of esters of polyfluorinated carboxylic acids on phases of different polarities and make it possible to estimate the enthalpy and entropy contributions to the energy of sorption of the esters, the effect of the temperature of the analysis and the length of the alkyl or polyfluoroalkyl chain on the retention parameters of the compound analyzed. The inversion of the retention order of trifluoroacetates and pentafluoropropionates in XE-60 nitrile-containing phase was found.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2051–2055, December, 1993.     

Fatty-acid composition of two <Emphasis Type="Italic">Limonium</Emphasis> plant species

The fatty-acid composition of two Limonium plant species (Plumbaginaceae), including both saturated and polyunsaturated acids, was determined for the first time using chromatography—mass-spectrometry. High contents of palmitic, oleic, linolenic, and linoleic acids were found. Methyl esters of fatty acids in Limonium Popovii were identified by mass spectrometry as hexadecanedioic, eicosanedioic, and docosanedioic acids.Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 344–346, September–October, 2004.     

Neutral lipids of the seeds ofPhlomis oreophilla andPh. regelii

The lipid and fatty acid compositions of the seeds ofPhlomis oreophilla andPh. regelii (familyLabiatae) have been studied. The lipids ofPh. oreophilla are enriched with linoleic acid and those ofPh. regelii with oleic acid. Laballenic acid is present in the total acids of the triacylglycerides and the free fatty acids of both species, being concentrated in the free acids. The epoxy acids ofPh. oreophilla are represented by 9,11-epoxystearic, vernolic, coronaric, and 15,16-epoxylinoleic acids.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 561–565, September–October, 1983.     

Reactions of benzamidoxime and its sodium salt with methyl esters of fluorinated acids

The reactions of benzamidoxime and its sodium salt with methyl esters of fluorinated acids at 20–100°C give 1, 2, 4-oxadiazoles or O-addition products.Translated fromIzvestiya Akademli Nauk. Seriya Khimicheskaya, No. 3, pp. 530–532, March, 1993.     

Molecular characteristics of water-soluble fullerene derivatives of amino acids and peptides

The diffusion of fullerene derivatives of amino acids and peptides in dilute aqueous solutions has been studied. These derivatives can exist in solution both as separate molecules and as associates. The degree of association depends both on the nature of the amino acid or peptide residue and on the concentration of the solution.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 879–882, April, 1996.     

Effect of the nature of the iron salt on the hydrothermal modification of ferrosilica gel

The effect of iron(III) salts (chloride or nitrate) on the hydrothermal modification of the texture and phase composition of ferrosilica gel has been studied. Special features in the crystallization of prepared specimens as a function of the nature of the anion of the initial iron salt have been revealed by x-ray phase analysis and nuclear gamma-resonance spectroscopy.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 24, No. 2, pp. 251–253, March–April 1988.     

Forms of adsorption of ethanol on anatase and paths of their transformation

The adsorption of ethanol on anatase was studied by IR spectroscopy and thermodesorption methods. It was found that three surface forms of the adsorbed alcohol are formed: a coordinatively bound alcohol to the oxide surface, and two types of ethylates. It was shown that a weakly bound surface ester participates in the formation of acetaldehyde, while the more strongly bound chemisorbed ester is responsible for the formation of ethylene and products of complete oxidation, depending on the content of oxygen in the gaseous phase.Irkutsk Institute. Translated from Teoreticheskaya i Eksperimental'naya Khimiya, Vol. 27, No. 2, pp. 232–237, March–April, 1991. Original article submitted April 21, 1987.     

Modelling the chemically induced liquid crystalline phases in mixtures of disc-shaped mesogens: the phase diagram of quadrupolar Gay-Berne discs revisited

We investigate the phase behaviour of pure systems and mixtures of quadrupolar Gay-Berne discs. The interaction potential mimics that of disc-shaped molecules which exhibit chemically induced phases with a structure based on columns of alternately stacking species. The phase diagram of the pure system is determined over a range of pressures, and the phase sequence is shown to include tilted columnar and nematic phases. The mixtures, in which the species have equal but opposite quadrupole moments, are investigated over a range of pressures using semigrand canonical simulations, such that the composition of the system is allowed to change. The fact that the composition is not fixed is especially important at the phase transitions, where the compositions of the coexisting phases may not necessarily be the same. In this situation, preparation of a system in the ‘biphasic region’ will lead to phase separation into the two distinct phases of differing compositions. The resulting phase diagram obtained using semigrand canonical simulations indicates that the columnar nematic phase observed in previous fixed composition simulations of this model [Liq. Cryst.,24, 229 (1998)] is not stable with respect to phase separation into an isotropic phase rich in a single component and a hexagonal columnar phase composed of roughly equal quantities of the two components. The structure of the columnar phase for the mixture is shown to be based on the alternate stacking of the different species. The relative concentrations of the different species in this phase may deviate up to approximately 60 : 40 mol%, after which any further material added will separate into the pure isotropic state.     

Acids and their functionally substituted esters fromAmaranthus cruentus seed oil

The acid composition of seed oil ofAmaranthus cruentus and the synthesis of their glycidyl and pyridinecontaining esters are studied. It is demonstrated that 67% of the total acids are C₁₈-polyunsaturated linoleic and linolenic. A new method for preparing glycidyl esters of C₁₈-unsaturated carboxylic acids is developed by reacting their salts with ECG in an aprotic medium to produce the corresponding glycidyl esters. The reaction of the glycidyl esters and pyridine salts with carboxylic and phosphonic acids produces the propanolpyridine esters of the acids that combine the properties of the acids and pyridinium salts and are promising in the search for biologically active compounds.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan' Scientific Center, Russian Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 217–219, May–June, 2000.     

The selectivity in MEKC of pseudo-stationary phases based on polyelectrolyte complexes: I. composition of the complex

Polyelectrolyte–surfactant complexes (PSC) of polycarboxylic acids with alkyl-trimethylammonium salts look very promising as a new type of pseudo-stationary phase in micellar electrokinetic chromatography. PSC produce an intramolecular micellar phase, and the morphology of the micelles is significantly different from that of the corresponding typical surfactant micelles. Pseudo-stationary phases based on PSC have unique selectivity. In this paper, the effect of the composition () of the PSC of polyacrylic acid (PAA) M_W 130,000 with dodecyltrimethylammonium bromide (DTAB) and of the PSC of PAA M_W 450,000 with DTAB on the separation of DNS–amino acids and phenol derivatives in these systems was investigated. Relative retention and relative selectivity were used to describe the electrophoretic behavior of the amino acids and phenol derivatives. The main advantage of PSC pseudo-phases is that the nature and the structure of micelle-like units, and hence the selectivity of electrophoretic separation, could easily be modified by changing the composition of the complex.