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A series of silica mesoporous molecular sieves SBA-15 with a 7.7 ± 0.8 nm pore diameter, the surface of which is hydrophobized with methylsilyl groups, and polymethylsiloxane derivatives with a 1.6 ± 0.8 nm pore diameter were obtained. These sieves are characterized by X-ray phase analysis, adsorption of nitrogen at 77 K and water at 293 K, as well as IR spectroscopy. It is established that there is a significant resistance to water intrusion (absorption) only in the case of substances characterized by the nitrogen adsorption potential value ∆μ0 ≤ 6.4 kJ/mol. The studied systems can be used as “molecular springs” in shock load damping devices due to their functional properties.

The set of compositions with Fe2+ in the system NaxFex/2Ti2–x/2O4 has been prepared by solid-state reactions in the inert atmosphere at 1050 °С. The oxidation state of iron was confirmed using the XANES method. Na0.88Fe0.44Ti1.56O4 is the new four-element compound in Na2O–“FeO”–TiO2 system. According to the X-ray powder data, it is orthorhombic, Pnma, a = 9.3624(1), b = 2.96718(4), c = 11.3435(1) A and has the same structure as Na0.9Fe0.9Ti1.1O4 with Fe3+. The structure was refined by the Rietveld method. The 3D-framework of (Fe, Ti)O6 octahedra contains quadruple rutile-like chains and sodium ions in double tunnels. Fe/Ti partial ordering in the framework and sodium distribution in the tunnels were studied additionally using the method of bond valence sums and Voronoi tessellation. The structure and composition of Na0.88Fe0.44Ti1.56O4 make it a promising material for cathode application.

The strength of the acid sites in isostructural hierarchical porous zeolites increases in the order BSiO < GaSiO < AlSiO, and the concentration in the structural types increases in the order MTW < BEA < MOR. Zeolite materials with BEA and MOR topology, which consist of nanocrystals with ultrathin-layer morphology, are characterized by a marked decrease of the adsorption potential compared with isostructural materials with nanorods or nanosphere morphology due to a 1.5-fold decrease in the isosteric heats of adsorption of triethylamine.

It was shown that porous coordination polymers (PCPs) of 3d metals containing chiral centers in fragments of deprotonated (S)-lactic and (R)-aspartic acid or trimesoyl-(S)-alanine are characterized by different values of sorption capacity with respect to the individual optical isomers of 2-butanol upon sorption of such substrates from the gas phase. The difference between the sorption capacity values with respect to the (R) and (S) isomers of 2-butanol correlates with the value of the enantiomeric excess achieved upon separation of the alcohol racemate on the respective PCP by column chromatography.

Lipids from the fresh aerial part, flowers, roots, and seeds of Ajuga turkestanica were studied. The contents, classes, and fatty-acid compositions of neutral lipids, glycolipids, and phospholipids of extracts and the compositions of free and bound lipids from seeds were established. Iridoids and traces of ecdysterone and flavonoids that co-extracted with the lipids and were characteristic of A. turkestanica were found in phospholipids of vegetative and generative plant organs.

Lipids from seeds with pericarp and leaves of Solenanthus circinnatus Ledeb. (Boraginaceae) were studied. The contents and class and fatty-acid compositions of neutral lipids, glycolipids, and phospholipids were established. The composition of unsaponified substances of lipids from seeds and leaves was determined. It was found that an insignificant part of S. circinnatus alkaloids was extracted with the lipids.

Lipids of Crambe abyssinica Hochst (Brassicaceae) seeds grown in hothouses in Israel and in the open in Uzbekistan in soil imported from the Aral Sea region were studied. It was found that the seed oil content decreased as the irrigation-water salinity increased. The content of total unsaturated fatty acids of neutral lipids was in the range 91.31–94.81%; of polar lipids, 69.59–83.78%.

A comparative study was carried out on the matrix polymerization of divinylbenzene, acrylonitrile, and methyl methacrylate in SBA-15 silica mesoporous molecular sieves. The occupancy of the matrix mesopores by the starting monomer, the medium, the polymerization temperature and time as well as the means of removing the exotemplate were all found to affect the spatial organization and porous structure of the polymer materials. Surplus occupancy of the mesopores by the monomer (1–1.5), polymerization in vacuum, and an alkaline method for matrix removal were found to be optimal. IR spectroscopy was used to find the conversion of the starting polymer by following the relative change in intensity of the vinyl group bands.

Coordination compounds of 3d metals with ligands — azoderivatives of benzidine and 2-hydroxybenzoic acids or 8-hydroxyquinoline — are shown to be characterized by a porous structure capable of absorbing substances of various types. The type of adsorbate is considerably influenced by the specific absorption volume of the complex.

1 Chair of General and Inorganic Chemistry, Faculty of Chemical Technology, National Technical University of Ukraine “KPI”, Prospekt Peremogy 37, 03056 Kyiv, Ukraine 2 Department of Organic and Inorganic Chemistry, University of Oviedo, 33006 Oviedo, Spain 3 Faculty of Chemical Technology, Kyiv National University of Technology and Design, Nemirovicha-Danchenko St. 2, 01011 Kyiv, Ukraine * Corresponding author. Tel.: +380-44-4549883; e-mail: andriiko@xtf.ntu-kpi.kiev.ua

Seed characteristics and the lipid and fatty-acid compositions were determined for the new cotton varieties ASh-25, Omad, 9771-I, Termez-43, and Bukhara-6.

We have shown that functionalization of MCM-41 mesoporous molecular sieves during their template synthesis using the effect of solubilization of organic hydrophobic co-condensing compounds makes it possible to obtain highly ordered mesoporous molecular sieves, with concentrations of vinyl or allyl groups covalently bonded to the surface of the silica matrix of about 3.5 mmol/g, which after sulfonation have acidic properties and exhibit catalytic activity in the process of ethyl tert-butyl ether synthesis.

Lipids of seeds with pericarp and an admixture of the air-dried aerial part (AP) of Heliotropium lasiocarpum Fisch. et Mey. (Boraginaceae) were studied. The contents and component and fatty-acid compositions of neutral lipids, glycolipids, phospholipids, and strongly bound lipids were established. It was found that part of the alkaloids was extracted together with the lipids from these plant organs. The chromatographic mobility of the heliotrope alkaloids was determined under the lipid separation conditions.

Lipids from the air-dried aerial part (AP) and seeds of Silybum marianum (L.) Gaerth. (Asteraceae) were studied. The class and fatty acid compositions of neutral lipids (AP, seeds) and glyco- and phospholipids (AP) were determined. Neutral lipids (NL) with a complicated set of lipophilic components, mainly triterpenols, sterols, and their esters predominated in the AP. The fatty acids of the AP were dominated by 16:0, 18:2 (glycolipids), and 18:3 (neutral lipids, phospholipids); of seed NL, by 18:2 and 18:1. The content and composition of flavolignans isolated from defatted seeds and the content of total protein in the meal were found.

Lipids from Crambe amabilis Butk. et Majlun and C. kotschyana Boiss. grown in the open in Uzbekistan in soil imported from the Aral Sea region were studied. It was found that the seed oil content decreased with increasing salinity of irrigation water with EC 1.5 up to 9.0 dS/m. The content of polar lipids increased. The content of unsaturated acids from C. amabilis neutral lipids was 94.74–97.46%; C. kotschyana, 95.76– 96.78%.

Polariton emission has been investigated in a GaAs based microcavity under various excitation conditions which excite predominately hot free excitons and carriers (He–Ne laser excitation), localized excitons (Ti–sapphire laser excitation), or mixed system. Strong differences have been found both in the intensity, the energy distribution, and the temperature dependence of polariton emission for the different excitation conditions. The relaxation into the low polariton branch due to consecutive scattering via polariton states in the bottleneck region and via the states of localized excitons has been found ineffective. Instead, we found that the highly effective filling of low polariton states occurs via relaxation of mobile excitons delocalized due to either thermal activation or interaction with hot carriers.

Lipids from roots ofAlthaea nudifloraandA. Armeniacawere studied. The carbohydrate and fatty-acid compositions were found. The lipids ofA. NudifloraandA. Armeniacacontain 22.3 and 12.6%, respectively, of cyclopropenoid fatty acids, the physical chemical properties of which are presented. The optimal degree of grinding, temperature, and raw-material-to-extractant ratio for aqueous extraction of water-soluble polysaccharides from althaea roots were chosen from a single statistically significant experiment

Photoluminescence studies of individual CdSe/ZnSe/ZnMnSe quantum dots (QDs) allow us to observe excitons and negatively charged trions in spectra recorded at liquid He temperatures. Exciton and trion lines equally split into a doublet of circularly polarized lines in a magnetic field B directed perpendicular to the sample plain. The ratio of intensities of lines in the doublet differs for excitons and trions. The difference can be explained if spin-dependent non-radiative recombination is taken into account. Contrary to expectations processes induced by the Coulomb interaction do not lead to such a recombination. The dominant mechanism of spin-dependent energy transfer from photoexcited QDs to Mn ions is related to the sp-d mixing. The efficiency of this mechanism substantially exceeds that induced by the Coulomb interaction. Suppression of the non-radiative recombination by a magnetic field in Faraday geometry leads to the increase in QDs PL intensity.

The field dependence of the magnetization of the isotropic ferromagnet, Ni 2 MnGa has been measured close to the Curie temperature of 363.0 (0.4) K and the critical index δ has been determined to be 4.77 (0.50). An analysis has been carried out to see if the index together with that of pure nickel could be described by the theory by Takahashi for a weakly ferromagnetic itinerant electron system or by conventional molecular field theory.

Comparative analysis of proteoglycans in the control and tumor tissue of human mammary gland revealed disorders in the biosynthesis of dermatan sulfate proteoglycans in tumor cells. Using the methods of reverse transcription-PCR and Western blotting for the analysis of decorin expression we showed that these disorders were paralleled by reduced expression of the core protein and changes in the structure of proteoglycan carbohydrate chains and could be a cause of malignant degeneration of mammary gland cells.

Lipids of leaves, runners, and stems of Callisia fragrans were investigated. Classes of neutral, glyco-, and phospholipids and their fatty-acid compositions were determined. The contents of ascorbic acid and organic acids and chlorophyll and carotinoid pigments in various plant organs were established.

Use of diamond grinding wheels with organic and ceramic bonds makes it possible to avoid the phenomenon of wheel glazing during fine grinding of molybdenum single crystals and to obtain a high quality ground surface with the minimum level of structural distortions. The nature of the orientation dependence of surface structural distortions is established by studying {001}, {110}, and {111} molybdenum single crystals. This is connected with features of plastic deformation during grinding.

Luminescence spectra of uniaxially and uniformly strained high-purity germanium crystals at liquid-helium temperatures in a magnetic field of up to 14 T have been investigated. In strongly strained Ge crystals, a new line has been detected on the low-energy side of the excitonline in magnetic fields higher than 4 T. Studies of this line’s characteristics as functions of pressure, temperature, and magnetic field have led us to conclude that its presence is due to recombination of electron-hole pairs in an electron-hole liquid. The experimental data suggest that the metallic electron-hole liquid is stabilized in a strong magnetic field. By approximating the shape of the newly detected line using the model of metallic electron-hole liquid, we have obtained the electron-hole liquid density n EHL(B) and Fermi energies E Fe,h of electrons and holes. The liquid binding energy o as a function of magnetic field has been estimated.

Lipids of Eminium Lehmannii leaves and tuber casings and cores were studied. Their class and fatty-acid compositions were determined. Leaf pigments were investigated.

Fruits of two varieties of Hippophae rhamnoides L. collected in Kyrgyzstan (I) and Uzbekistan (II) were investigated. Differences in their morphological and biochemical properties were demonstrated. Titrable acids, ascorbic acid, and protein dominated in the fruits of I. Pulp oil of II contained more free fatty acids (acid number 2.9 mg KOH) and carotinoids (419.3 mg%). The principal pulp acid was 16:1. Among the rarely encountered acids of pulp oil, an insignificant quantity of 16:2 was detected (1.2–4.6%). Seed oil of the studied specimens contained >40% of the essential acids 18:2 and 18:3 (vitamin F).

The composition and amounts of various classes of lipids of the seeds of Hibiscus sp. have been investigated. Seven classes of neutral lipids, five of phospholipids, and five of glycolipids have been identified and their fatty-acid and triglyceride compositions have been established. The presence has been shown of 16 main types of triacylglycerols and 25 types of epoxyacyldiacylglycerols. An epoxy-18.0 and an epoxy-18:1 acid in a combined amount of 1.4% have been detected among the acids of the free lipids, together with 8.1% of cyclopropenoid acids.

Unsaponified compounds of lipids from Mediasia macrophylla were investigated. They were found to contain about 50% essential oil. The content of petroselinic acid in the mixture of acids isolated from the neutral lipids and glycolipids of the leaves was determined by TLC, GC, and destructive oxidation.

The lipid composition of ripe and green fruit of Hibiscus esculenthus cultivated in Uzbekistan was studied. The fatty-acid composition of pod and seed lipids was determined. Carbohydrate components including water-soluble polysaccharides, pectinic substances, and hemicellulose were characterized.

We have experimentally investigated the process of propagation of the burning front along the surface of powders of titanium, magnesium, and mixtures of magnesium with diluents in an air atmosphere. We have determined the dependence of the velocity of propagation of the burning front along the surface of bulk metallic powders on the angle of inclination of the test bed of powder, and also the effect of additives introduced into the powders. We used several types of additives: free-burning in an air atmosphere, inert with high melting point, and low-melting-point inert powdered materials not burning in air but reacting exothermically with the metallic powders. In addition to our purely scientific interest, we also pursued a practical goal: solving problems of reducing fire and explosion hazards for production processes using or manufacturing metallic powders and mixtures based on such powders.

Lipids from Mediasia macrophylla leaves were studied. Classes of neutral, glyco-, and phospholipids and their fatty-acid composition were determined. The content of chlorophyll and carotinoid pigments in the leaves and lipid extract was found. Essential oil was isolated by steam distillation and contained free and bound fatty acids.

An experimental study of the effect of foreign inclusions of both chemically active materials, capable of burning in an air atmosphere and inert oxide materials on the propagation of a combustion front over the surface of titanium powders was carried out. It has been established how the character and the rate of surface combustion Vc of titanium powders change upon their dilution, depending on diluent concentration, melting temperature, disperse composition, and chemical activity.

The compositions and amounts of polar lipids in cotton seeds and the products of their processing have been investigated. Six glycolipids have been identified, the main ones being monogalactosyldiglyceride (MGDGs), digalactosyldiglycerides (DGDGs), and sterol glycosides. The fatty acid compositions of the neutral lipids and of the phospho- and glycolipids have been determined. In the glycolipids, saturated fatty acids — palmitic and stearic — predominated.

Lipids of the leaves, stems, and rhizomes with roots ofAcorus calamusL. were investigated. The neutral-lipid classes and fatty-acid composition of neutral-, glyco-, and phospholipids were determined. The essential oil content in the total lipids of A. calamus was established by steam distillation.

Experimental data on degradation of photovoltaic and photoenergetic characteristics of silicon solar cells exposed by high-energy electrons and protons as well as low-energy protons have been obtained. The previously proposed theoretical model that can describe degradation of the solar cell characteristics under the influence of irradiation, including that creating spatially inhomogeneous defect distribution over the structure thickness, has been experimentally confirmed. It was ascertained that in the cases of 1 MeV energy electron and 20 MeV energy proton irradiations, when there is a relatively homogeneous defect distribution over the silicon solar cell thickness, its shortcircuit current degrades faster than the open-circuit voltage. On the contrary, in the case of low-energy 0.1 MeV proton irradiation, when the distribution of defects is spatially inhomogeneous, the open-circuit voltage degrades faster than the short-circuit current.

The compositions of classes and fatty acids inArum Korolkowiitubers are determined. The principal acids are 16:0, 18:1, and 18:2. Triterpenes, 4-monomethylsterol, and sterols are found among the unsaponified substances

The composition and lipid content of the lipoprotein complexes of cotton kernels (I), meal (II), and isolate (III) have been investigated. It has been shown that with the aid of an acidic alcohol-containing extractant it is possible to isolate up to 99% of the strongly bound lipids (SBLs) of their total mass. In the composition of the strongly bound lipids (I–III) have been found neutral lipids comparable with the free lipids of the kernel; of polar lipids, glycolipids were present. It was found that an acid extractant extracts polyphenolic compounds together with the SBLs.

The composition of free, bound, and strongly bound lipids ofAmaranthus sp. is studied. The fatty-acid composition of separate lipid classes is determined. Unsaponified sterols that were fractionated by TLC into five components were isolated.

The chemical composition of the seed lipids ofAmaranthus caudatus L. has been investigated. The fatty acid compositions of the neutral lipids and of the phospho- and glycolipids have been determined. The hydrocarbon components ofA. caudatus have been identified and its alcohol-soluble carbohydrates, water-soluble polysaccharides, and pectin substances have been characterized.

The unsaponifiable substances of the lipids of the leaves ofHibiscus sp. have been studied. The compositions have been found of seven classes of compounds: hydrocarbons, carotenoids, tocopherols, isoprenols, triterpenols, and phytosterols and their esters.

The lipids of the leaves, stems, and roots ofHibiscus sp. have been studied. Their fatty acid compositions have been determined. The greatest amount of unsaturated fatty acids was present in the glycolipids of the leaves and the stems. More than 25% of low-molecular-mass C10-C12 fatty acids have been found in the neutral lipids of the roots.

The composition and amount of lipids in the seeds and leaves of the cotton plant of variety 6524 S over the vegetation periods have been investigated. The rate of biosynthesis of neutral lipids in cotton seeds in the 20-day period after flowering to the moment of maturation increases by a factor of 1.6 while the amounts of phospho- and glycolipids decrease by factors of 3.9 and 4.3, respectively. The fatty acid compositions of the neutral lipids and of the phospho- and glycolipids of the seeds and leaves have been determined.

Free and bound lipids from Helianthus tuberosus tubers were investigated. Neutral, glyco-and phospholipid classes and their fatty-acid compositions were determined. The composition of unsaponified substances was established.

There has been a considerable progress in the photoluminescence (PL) properties investigations of SiGe/Si and Ge/Si structures of late. The PL investigations of Ge-Ge1-xSix structures with quantum wells in germanium layers have been started recently1,2. This work reports the studies of the exciton and magnetoexciton luminescence of Ge-Ge1-xSix heterostructures grown by CVD method on Ge [111] substrates.

The authors demonstrate efficient hole spin injection from a ferromagnetic metal (Ni) contact in a forward biased light emitting Schottky diode (LESD) fabricated on a GaAs based heterostructure with a quantum well (QW). The spin polarization of the injected holes was detected by measuring the circular polarization of the electroluminescence (EL) from the near surface InGaAs∕GaAs QW. An intermediate gold layer has been used in order to improve the spin injection efficiency. Over 40% degree of circular polarization of the EL has been observed at T=2K for the LESD structure with Au–Ni–Au Schottky contact.

On the basis of a quantitative analysis of the volatile carbonyl compounds present in acetone-treated meal it has been shown that they contain a total of about 11 compounds, the main ones of which are acetone and mesityl oxide.It has been established that the moist heat treatment of extraction meal does not lead to the complete elimination of these compounds, and under severe conditions it actually leads to an increase in the amount of carbonyl compounds through degradation of, mainly, the fatty fraction of the meal.