Home – Home – Jornals – Chemistry for Sustainable Development 2007 number 1

Peculiarities of sterilization and germinаion of the seeds after different storage periods as explants for introduction into culture in vitro are considered along with the features of morphogenesis and shoot regeneration of S. umbrosa in Murasige and Skuga nutrient medium with the addition of some hormonаl factors. The initial stages of the ontogenesis of fig-wort were studied in vitro. Microclones introduced under the conditions close to those in the natural habitats of the species were under observation.
On the basis of this research, a detailed technology of S. umbrosa micropropagation was elaborated. The reduction of the development cycle and formation of viable seeds in the introduction of microclones developed in vitro was demonstrated.

Dependence of the variation range revealed in the electrophoretic spectra of seed polypeptides on the ecological-phytocoenotic conditions of 13 populations of Hedysarum theinum Krasnob. (tick trefoil) was investigated. It was discovered that the variation range of the seed polypeptide spectra for the populations of H. theinum from the high-mountain belt of vegetation is smaller than for the populations from the forest belt. The latter is also characterized by the presence of populations in which extremal variation values were observed. Populations from the high-mountain vegetation belt which are borderline with respect to the altitude above the sea level were characterized by not very high variability.

A comparative anаlysis of taxonomic structure was carried out in ten regional partial floras (PF) of basins in the latitudinal and longitudinal gradients. The South-Eastern position of PF in the basins of the Ilmen State Reservation in the considered edaphic-climate profiles was determined. A new border of the domination of Cyperaceae-type spectra was revealed. It passes through the boreal zone and sub-zone including highlands.

The list of rare plants conserved in the Nationаl park Tunkinsky includes 44 species. Exact locations and brief characterization of habitats are presented for these species. The comparative anаlysis of the sites of rare species with respect to the existing functional zones of the park is performed; the efficiency of their protection is shown.

Data on the seasonаl rhythms of development of the representatives of Lamiaceae family - Ballota nigra L., Dracocephalum ruyschiana L., Hyssopus officinаlis L., Scutellaria baicalensis Georgi, аnd Asteraceae family - Eupatorium cannаbinum L. are presented. The cytoembryological investigation of these species was carried out, including the phases of flower development, morphological features and fertility of pollen grains.

The data on individual variability of Siberian larch cones in field-protective plantations of Shira steppe of Khakasia are presented in the paper. Three forms of cones were revealed according to their colour, such as green-coned, red-coned and transitional forms. The technical germinating capacity and quality of seeds from different forms of cones (green-coned, red-coned and transitionаl) were determined.

Accumulation and variability of ecdysteroids in the phytomass, which are analogs of the insect moulting hormones, were studied in ontogenesis of the agropopulations of Rhaponticum carthamoides (Leuzea carthamoides DC.) and Serratula coronаta, with relation to the age and plant cultivation conditions. The physiological role of ecdysteroids in the ecological mutual relations with pests was evaluated.
It was revealed that the enhancement of the activity of phytophagans coincides with biochemical changes in the composition of ecdysteroids, possessing various kinds of physiological activity, and is accompanied by damage of reproductive organs. During the age-related changes in ontogenesis and seasonal development during the vegetative period, the individual share of physiologically active ecdysteroid 20-hydroxyecdysone decreases, while the low-activity ecdysteroids inokosterone and ecdysone are accumulated in generative sprouts.
Concentrating of the low-activity ecdysteroid ecdysone in the phytomass is affected by the ecological conditions of the environment and anthropogenic factors of cultivation. The factors promoting realization of the potential of affection by pests are the microclimate of the environment, accommodation of populations over the relief elements of the area, and the performed agrotechnical actions (intensity of phytomass removal, superfluous humidity in the rooting layer of populations).
The work was done under partial financial support granted by the administration of the Arkhangel'sk Region and the Russian Foundation for Basic Research (RFBR) NN 08-04-98840, 03-04-96147.

The problem of preservation of a relict of nemoral flora Menispermum dauricum DC. in nature is considered. The age structure and features of six local populations are studied. It is shown that, in spite of fact that the species is phytocoenotic patient, local populations on mountain-steppe slopes are influenced by destructive exogenous geomorphological processes. For preservation and restoration of Menispermum dauricum, reservations should be organized. This will also help to introduce and reintroduce Menispermum dauricum.

Data on 22 Southern-Siberian vascular plants of Amurskaya province are listed with the brief taxonomic, geographical, ecological-and-cenological analyses. The problems of conservation of the rare and endangered plant species are considered. The author proposes to establish 2 regionаl refuges in the Amur basin for the conservation of Southern Siberian plants included the Red Book species.

Distribution of lichens in forest and part zones of Novosibirsk is investigated. Lichen synusia on soil, on decomposing wood, on the bark of indigenous and introduced tree species are revealed, the anthropogenic transformation of lichen synusia is analyzed.

The concentration of phytoplankton photosynthetic pigments was monitored every decade on the Biya River outflow at the site located in the direct vicinity of Lake Teletskoye, from July 1998 till December 2001. The phytoplankton pigment characteristics in this site and in the surface layer of the lake area were compared. Processes of lake phytoplankton development and functioning are represented in full at the river site, as are changes of pigment composition that follow dynamic regularities. On the basis of seasonal variations of pigment concentration and ratios, the main phases of planktonic algal cenoses development were revealed. The comparison of phytoplankton seasonal dynamics in this deep oligotrophic lake and the lakes of different types in the temperate zone was made. The trophic status of the pelagic zone and outflow at the Biya River defined by chlorophyll a content corresponds to the ultraoligotrophic-oligotrophic one. The relationship between green and yellow pigments classifies Lake Teletskoye as a water body of «carotene» type. A lack of linear relationship between chlorophyll a content and water level, as well as weak correlation with nutrients, testify to a complex interdependence resulting from synchronous effect of abiotic and biotic factors.

On example of plaining Karasuk river (Western Siberia) it was discussed the indicative significance of taxonomic structure, values of number and phytoplankton biomass and the application of these indices for characterizing the water quality are discussed for the example of the Karasuk, a plain-land river in West Siberia.

Vitality of individuals and coenopopulations of rare and relict species (Sophora flavescens Soland.) were studied. Number and length of shoots, number of leaves on a shoot and the ratio of the leaf length to its width are the main signs characterizing the vitality of an individual. Different combinations of these quantitative signs characterize the vitality of each individual quantitatively. Such characteristics as the type of population, average points of individual vitality in the population, the sufficiency of age spectrum, the presence of genets and ramets and abundance of species in community are important indices in determining the vitality of coenopopulations. It was noted that individuals in young and transitional populations have high points of vitality.

The population of Gymnodinium baicalense Antipova from Lake Baikal was investigated alive. Living vegetative cells of G. baicalense are closely related morphologically to G. wigrense Woіosz. These species have identical ecological features. Vegetative cells are forming endogenous rest cysts. Sexuаl reproduction occurred during the mass development of the species.
The author believes G. baicalense is a relict species and its formation has taken place during the ice age.

The role of lichens in high-mountainous belt in epilit-lichens tundra, cobble tundra, alectoria tundra, dryad tundra, bush-lichens tundra, fescue tundra, cobresia and yernik tundra - integral components of mountainous vegetation - was studied and analyzed.

On the basis of long-term monitoring (1926-2003) at a permanent test ground arranged by B. A. Ivashkevich in an overmature virgin hornbeam cedar forest with fir, it is concluded that natural decomposition of the cedar part occurs in the tree stand; cedar had lost its dominant part. At the same time, secession of the tree species dominating in the lower canopy that had completed their life cycles occurs. However, the dead generations of these species are rapidly replaced by the young ones, while the young generation of cedar able to form a new tree stand is almost unformed. All these facts provide evidence of distortion of the cyclic character of cedar digenesis. The phase of predominance of hardwood species begins.

Investigation of the variability of morphological indices of Alnus fruticosa s. l. at the territory of Asian Russia was carried out. It was revealed that the species possesses a complicated internal structure, which is due to the features of climatic and foresting conditions in different parts of the habitat.
The results of phenotypic variability and sequences of intergenic spacer ITS1 nuclear eibosomal RNA of the taxons of Alnobetula subgenus point to the species rank of Alnus viridis and subgenus rank of A. fruticosa, A. sinuata and A. crispa with the priority specific name A. crispa.
A. maximowiczii, A. glutipes, A. kamtschatica and A. mandshurica are the result of intraspecific variation of the polymorphous species A. fruticosa.

Effect of optimal and contrast temperature on the fractional composition of proteins and respiration of germinating seeds of Gmelin larch (Larix gmelinii (Rupr.) Rupr.) and Siberian larch (Larix sibirica Ledeb.) is revealed. Prevalence of globulins (salt-soluble fraction) and the fraction of insoluble proteins was detected in the viable air-dry larch seeds. Optimal and contrast temperature of seed germination caused substantial changes in the content and dynamics of separate protein fractions. Contrast temperatures caused stronger changes: the content of insoluble proteins increased, intense consumption of globulins occurred as separate stages of germination. Seed respiration during germination at contrast temperatures increased to a higher extent than it did at the optimal temperature. Temperature mode of germination also affected the character of interrelations between respiration intensity and the content of different protein fractions.

Features of substrate specialization of 196 species of wood-destroying aphyllophoroid fungi were revealed in the pine forests of the right-bank upper Ob territory. Distribution of species on deciduous and coniferous species in connection with confinement to substrates was demonstrated: over the types of rot caused by them, in connection with the character of substrate. The largest number of the species of wood-destroying fungi develops on forest-forming tree species. The majority of species develops on deciduous trees, the majority of white rot fungi is also confined to these tree species.

Structure and morphology of mechanocomposites based on tungsten with copper, nickel or iron added were studied by means of X-ray diffraction studies, electron microscopy and micro- X-ray spectral analysis. The possibilities of rpessing dense samples from the obtained mechanocomposites were demonstrated.

Novel universal approach to obtaining multilevel nanocomposites with different architectures including interpenetrating structures and nucleus - shell structures is proposed. The approach is based on the deposition of charged aerosol particles with the size 30 nm to 300 μm with the help of electric mass classifier. In view of the small excess charge of particles and the large dipole moments, the coating density after deposition is very low. After the fixation of the porous framework by agglomeration, the relative density of the ceramic coating equal to 0.04 was achieved. Filling of the framework provides the possibility to obtain a broad range of interpenetrating composites. The use of mechanocomposites for making aerosol allows one to obtain multilevel composite materials with required architecture.

In this work the experimental results of the investigation carried out on the use of micronized fly ash as pozzolanic material for production of cement mortars are presented. The milling of fly ash was carried out in planetary ball mill; the size distribution of micronized material was similar to silica fume, normally used to produce high strength conglomerates due to its very high specific surface. Micronized material was also beneficiated reducing the unburned fraction by means of triboelectrostatic separation. The mechanical strength tests of mortars were performed through the substitution of cement or sand (between 10 and 25 % in mass) with Micronized Fly Ash (MFA), Beneficiated Micronized Fly Ash (BMFA) and Silica Fume (SF), respectively. The water/cement ratio (w/c) was regulated to obtain equal workability of the mixtures (from 0.35 to 0.4). The best value of compression strength at 28 days (more than 100 MPa) is obtained with BMFA (in substitution of sand): this value is 34 and 10 % higher than reference  mortar with Ordinary Portland Cement (OPC) and mortar with SF, respectively. On the basis of these results a chemico-physico-mechanical improvement of the fly ash was achieved making reutilisation of this by-product in high strength cement conglomerates feasible.

Alumina-zirconia nanocomposite powder with a particle size around 50 nm was synthesised by mechanochemical activation. Milled powders consisted of CaO and XRD amorphous aluminium and zirconium chloride phases. After annealing the milled powder at 360 ^oC displacement reactions occurred and ZrO₂ and Al₂O₃ nanoparticles were formed in a CaCl₂ matrix which was removed by washing. DTA, XRD and SEM analysis were applied to characterise the powders. The formation of cubic zirconia and α-alumina were observed at very low temperatures.

The austenitic stainless steel materials modified with nano-SiC powder were prepared under the production conditions by foundry method. The corrosion resistance for different amount of SiC added to stainless steel was investigated. The results showed that with the addition of nano-SiC powder, the resistance to chemical corrosion and electrochemical corrosion was markedly improved. The addition of nano-SiC powders can significantly enhance the intergranular corrosion of stainless steel, and the anti-intergranular corrosion of the stainless steel was the result shown both by the metallographic and the bending methods. With the addition of nano-SiC powder, the ferritic and chromium of the stainless steel reduce segregation, so nano-SiC powders can help effectively avoiding the two-phase chromium depleted zones and areas prone to localized corrosion, such as the emergence of the region.

Three different α-Al₂O₃ nanopowder species were characterized; their behaviour under dry uniaxial compacting and agglomeration without applying external pressure was investigated. Ceramics dense at a level of 99 % was obtained at agglomeration temperature 1300 ^оC; hte grain size was about 200 nm. It was established that for low-temperature agglomeration it is reasonable to use the powder containing aggregates that are conserved during filling the press mold at the initial stage of pressure rise but get destroyed at subsequent stages of compacting. It was demonstrated that with the optimal molding method is becomes possible to obtain dense ceramic material even at 1150 ^oC, with the conservation of grain size at a level of 100 nm and less.

Nanodisperse powder of magnesium meta- and ortho-silicates was obtained with the help of the solid-phase exchange reaction of magnesium chloride with sodium silicate (using NaOH or without it) proceeding under mechanical activation. The formation of enstatite and forsterite proceeds through the X-ray amorphous (or weakly crystallized) hydrated compound during the subsequent thermal treatment. A comparison with the known method of obtaining these silicates under mechanical activation of the mixtures of magnesium hydroxide and silica gel was carried out.

The influence of thickness of self-lined layer of processed substances on the parameters of mechanical activation is considered. Theoretically, using quartz as an example, dependencies of impulses of pressure and temperature along the layer thickness are calculated. It is shown that this parameter affects significantly the kinetics of mechanochemical processes.

Possibilities to use atomic force microscopy (AFM) as a tool to study morphological features and structural parameters of mechanochemically synthesized alloys and structural parameters of mechanochemically synthesized alloys and metal cements based on them are presented. It is stressed that the application of AFM to the investigation of diffusion-hardening alloys characterized by long-term structure forming process allows one to investigate the intermediate states of the surface. A comparative analysis of the data obtained with the help of atomic force microscopy and scanning electron microscopy was carried out.

Macrokinetic characteristics of the combustion process in reaction mixtures Cr-B and Cr-Ti-B after preliminary mechanical activation were investigated. It was established that mechanical activation has a substantial effect on the composition and structure of the initial mixtures and therefore on temperature and rate of combustion of the mechanically activated mixtures. It was shown that the interaction between the reagents at the combustion temperature follows the solid-phase mechanism. The mechanisms of phase formation in the combustion wave were studied with the help of stopped-front method. With an increase in the concentration of oxygen in the mixture as a consequence of mechanical activation, the role of gas transport of boron to the surface of the metal increases; reaction diffusion becomes the limiting stage of the interaction of a metal with boron. It was established using X-ray structural analysis that the products of combustion of the mixture Cr-Ti-B contain previously unknown ternary compounds like Cr₄Ti₉B and Ti₂CrB₂.

Effect of attritor mechanical activation on the structure and reactivity of powder mixture Fe-45 mass % Al for self-propagating high-temperature synthesis (SHS) of powders based on iron aluminides was studied. It was established that the decisive influence on the change of the mechanisms of phase formation during SHS is exerted by the level of micro-heterogeneity of the reaction mixture and the formation of nanometer-sized iron aluminides В2-FeAl and/or Fe₂Al₅ in mechanically activated powder mixtures.

X-ray diffraction, Mossbauer and Auger electron spectroscopy, electron and atomic force microscopy were applied to study the sequence of structural-phase transformations during mechanical alloying (MA) and annealing of system iron - titanium - carbon obtained using the mixtures of different compositions: powders of pure elements Fe (70 at. %), Ti (15 at. %), graphite (15 at. %); powders Fe (70 at. %) and TiC (30 at. %); powders Fe (70 at. %), Ti (15 at. %) and toluene. It was demonstrated that in all the cases MA results in the formation of nanocomposite powders with complicated phase composition: a solid solution based on Fe, X-ray amorphous phase based on carbides TiC and Fe₃C, carbide TiC. Annealing leads to the crystallization of the amorphous phase, decomposition of the solid solution and formation of nanocomposite Fe + TiC + Fe₃C. The dispersity, number of composition of carbide phases depend on MA conditions. In the case of the mixture of Fe, Ti and toluene, by varying MA time one may obtain the two-phase system Fe + TiC with the uniform distribution of nanocrystalline phases over the sample.

The possibility of the mechanochemical synthesis of nanopowders of magnesium and zinc oxides for use as modifying additives to polymers was studied. The process of obtaining nanopowder includes four stages: dehydration of the initial salt, treatment in the planetary mill, washing by means of decantation, and drying. Manganese and zinc chlorides were used as the initial salt. Dehydration was carried out at a temperature corresponding to the removal of adsorption and crystallization water as determined by means of TGA. Then the salt was treated in a planetary mill for 2-3 h in the presence of a phase separating agent (sodium nitrite NaNO₂). The treatment process was accompanied by powder dispersing and the mechanochemical reaction between the initial chloride and the salt matrix of NaNO₂. The moment of reaction completion was determined on the basis of pressure change inside the reaction volume with time. The mixture of oxides and water-soluble salts, obtained as a result of the mechanochemical reaction, was washed by centrifuging and then the formed precipitate was dried. The resulting oxides were investigate with the help of X-ray structural analysis, scanning electron microscopy, measurements of specific surface with the help of BET procedure, laser analyzer of particle size. It was established that the proposed procedure allows obtaining oxide particles with the average size of 60-140 nm.

The features of phase and structural transformations in the powder of graphite-like boron nitride occurring as a result of the treatment in attritor are considered. It is established that attritor treatment causes an increase in the specific surface of boron nitride particles by more than an order of magnitude. An increase in the time of mechanical activation of the powder causes the transformation of the substructure of BN from the crystal to nanocrystalline and amorphous. It is shown that phase transformations with the formation of rhombohedral BN and high-pressure phases - wurtzite and cubic BN - with the particle size of submicrometer range proceed in boron nitride. When the optimal intensity and duration of treatment are exceeded, reverse transfer of cubic boron nitride into graphite-like (hexagonal) boron nitride with recrystallization of the latter is observed.

The zones of normal-tangential indenting (N-TI) of the single crystals of apatite, quartz and lithium fluoride were examined by means of scanning and high-resolution electron microscopy. The texture, structural and phase transformations thus detected were conventionally related to the "deformation" and "diffusion" processes of plastic deformation. Two levels of structural transformations were revealed in the zones of N-TI in signle crystals; a sharp boundary between them occurs at the strain equal to the theoretical strength limit (σ_tsl). In the upper zone of scratches within the strain range from microhardness value H_ц to the σ_tsl value, the substance undergoes profound structural and phase transformations with the formation of the amorphous state, "paracrystalline", "liquid crystal" and "two-dimensional" nanoparticles. The substance in the zone of scratches is a model of mechanically activated substance. In the bed of scratches at the strain below σ_tsl we observe fragmentation of single crystals with the formation of blocks and steps; this is a model of the grinding process. A wave model is proposed for the transformation of the input mechanical energy for indention with the specific power approximately equal to 3 · 10¹¹ J/(m³ · s), which is close to the level of atom bond strength in the activated zone of N-TI. As a result of excitation of chemical bonds, phase and structural transformations occur in the activated zone of N-TI.

Ideas of sustainable development spreading through the educational system form the framework of innovative programs. The problems of sustainable development are recognized as a constituent of professional training in many areas. It is shown with the example of D. Mendeleev Russian University of Chemical Technology that the innovative potential of sustainable development becomes the driving force of modern education. The principles underlying education for sustainable development include understanding of interdisciplinary relations and responsibility for social consequences of application of knowledge.

A review of the literature data is presented, as well as the results of the own authors' investigations in the area of development of synthesis procedures, studies of the reactivity, and search for the ways of the practical application of mono- and bis-triorganylsilyl derivatives of 1,1-dimethylhydrazine with the general formula R_{4 - n}Si(NH-NMe₂)_n where n = 1-4, and (R₃Si)₂N-NMe₂.

A set of the problems and directions of the accelerated development of the methods of synthesis of fluorine-containing β-sultones by means of the interaction of sulphur trioxide with perfluorinated olefins is considered in connection with the outlooks for their wide use to obtain fluorinated materials for a broad range of practical applications. For instance, they are used as semi-products to obtain polyfluorinated sulpho- and carboxylic acids which are involved in the manufacture of fluorinated membranes for electrochemical processes. The effect of substituents at the unsaturated bond on the formation of a four-membered cycle and the effect of Lewis acids on obtaining unsaturated fluorosulphates. The areas of application are described.

The concentrations of heavy metals (mercury, cadmium, lead, copper and zinc) in needles of Pinus sylvestris growing at the polluted and background territories of the basin of the Selenga River are investigated. The dependence between the metal content of needles and the soil is shown. Using the concentration coefficients for different pollution zones, the rows of metal accumulation in pine needles are arranged; they depict the level of the emission load on forests. In the zone of strong pollution, the highest correlations between the concentrations of lead and cadmium in needles and the morphometric parameters of trees are detected.

Comparative analysis of the element composition of diet and tissues (liver) of the individuals of bank voles (Clethrionomys glareolus) and common shrews together inhabiting chemically polluted (impact) and non-disturbed (background) territories of the Middle Urals was carried out. The obtained data allow one to estimate the role of ecological factors in the formation of biogenic cycles of chemical elements participated by the mammals belonging to different links of trophic chains. The group of phytophages (voles) occupies a special place in the translocation of chemical elements over the trophic levels of mammals. The specific features of feeding for these species and the existence of the gastrointestinal barrier limit the accumulation of elements in animal organisms. Under the same conditions, carnivores (common shrew) play the part of concentrators of a number of chemical elements (Pb, Cd, Cr, As etc.) in the mammal community. The concentrations of these elements increase in the animal organisms in comparison with their concentrations in their food. The toxic load on an animal organism (liver) does not depend on the trophic specialization.

Problems of synthesis and transformations of liquid redoxites have been considered in extraction systems and in systems that contain cations of metals of variable valence. A new method has been put forward to reduce (or to oxidize) cations of d-elements in water solutions of their salts by a liquid redoxite that is present in an organic phase. The procedure can be employed in extraction and separation processes for cations of metals, in the systems where redox processes occur at the phase boundary, and also for organic syntheses that represent a redox process.