Вестник БГУ. Серия 2. Химия. Биология. География

The data on synthesis, physico-chemical properties and application of tetrazole-containing polymers (TP) – polyvinyltetrazoles, other carbo- and heterochain polymers with tetrazole cycle attached to the chain immediately or throw different substituents, polymers with tetrazole ring in the chain (polytetrazoles) including linear, ramified, star-shaped and hyper-ramified, as well as coordination TP and polymeric salts, published mainly during last 5–7 years, have been classified and generalized. The methods for preparation of TP by (co)polymerization, polycondensation, polyaddition of functionally-substituted tetrazole derivatives and polymeranalogous conversions have been considered. The developed approaches to the syntheses of TP have been shown to direct for preparation of products characterized by value practical properties including both well known and used in machinery (further directed regulation of properties of TP as an efficient binders for different kind combustible and thermally decomposed systems, sorbents for extraction of transition and noble metals from different systems) and novel ones. These are TP which are able to change their properties under the action of external conditions and are promising precursors for production of pH-thermosensitive materials, proton-conducting and gas-separation membranes, special agents for introduction of marks into proteins of living systems, super water absorbents, chemical sensors, micromesh high-strength monoliths, optical-active and other materials

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Extraction was found to be effective method for isolation of n-butyl alcohol and other accompanying products (ethanol, acetone) from culture broth of acetone-butanol fermentation. Culture broth obtained by fermentation of rye flour by Clostridium acetobutilicum, was used as a object of research. Chloroform, toluene, tributylphosphate, rape seed oil, n-octyl alcohol and n-decyl alcohol were tested as extractants. Among them, n-decanol having high extraction capacity, low inflammability, volatility, solubility in water and low toxicity to Clostridium acetobutilicum was found to be the most promising extractant, especially for use in industrial scale. Since extraction doesn’t allow isolate n-butyl alcohol and other products completely, extraction approach is perspective for using in continuous fermentation-extraction process with recycling of culture broth.

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The article is devoted to the problem of platinum group metals recovery from the secondary raw materials, such as radioelectronics and condenser scrap, spent catalysts, exhaust gases neutralizators. In Belarus collection, primary and deep chemical conversion of scrap and different waste materials, containing precious metals, is carried out by UE «Unidragmet BGU». The activity of the enterprise is aimed at both the obtaining of the output with the precious metals and widening of analytical part in the case of precious metals determination in different objects. The method of platinum group metals determination by fire assay technique was described in application to the secondary raw materials. The results of determination of precious metals in the electronic scrap samples with the use of lead, copper and nickel sulfide collectors are presented. Due to the results the procedures of measurements of platinum, palladium and rhodium in exhaust gases neutralizators on ceramic support were elaborated and certified.

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The research of length influence of hydrocarbonic substitutes at quaternary ammonium salt (QAS) nitrogen atom to analytical characteristics of tetraftoroborate electrodes has been carried out. The functions of electrodes have gradients similar to theoretical. The detection limits change from 5,0·10–6 to 1,3·10–6 mol/l. The values of potentiometric selectivity coefficients decrease with increasing length of the hydrocarbonic substitutes at QAS nitrogen atom. The reason is the correlation of the constant of main and interfering anions assosiation with ion-exchanging QAS centres determines the one-charged ions potentiometric selectivity coefficients. The constant of main and interfering anions assosiation with ion-exchanging QAS centres are the function of value reverse to short range parameter «a» and described by Aygen – Denison – Ramzi – Fuoss equation. Parameter «a» is an additive function of ion association effective radii. The effective electrostatic radius of QAS cation having more than four carbon atoms in substitutes are much less than geometric radius and practically don’t depend on quantity of carbon atoms in them because an anion can percolate through alkylic chains. In this way it is the most effectually to use QAS having carbon atoms more than four in radicals for the creation high-selectivity tetraftoroborate electrodes.

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The influence of the plasticizer nature on the selectivity of electrodes based on neutral carrier – heptyl 4-trifluoroacetylbenzoate – to tetrazole anions and its 5-monosubstituted derivatives is investigated. It is shown that the selectivity of the electrodes increases towards tetrazole ions against perchlorate conforming to the decrease of plasticizer basicity in the series dibutyl adipinate > bis(2-ethylhexy) sebacate > dibutyl phthalate > 2-nitrophenyl octyl ether which is explained by competitive interaction between plasticizer (donor) and neutral carrier (acceptor). Correlations have been found, namely selectivity of tetrazolate-selective electrodes caused by the introduction of the neutral carrier into the membrane improves with the increase of the electron donor ability of the substituents in the tetrazole ring, and selectivity coefficients of electrodes towards tetrazole anions against perchlorate are proportional to distribution constants of those tetrazolates in n-octanol-water system.

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Qualitative and quantitative composition of complex formed during chromium(III) acetate reaction with terpolymer of acrylamide, 2-acrylamide-2-methyl-propanesulfonic acid sodium salt and sodium acrylate in an aqueous solution resulting in transformation of linear macromolecules into a space network has been estimated by NMR 13C spectroscopy. A cross-linking has been shown to proceed only by an interaction of chromium(III) cation and carboxylate groups of the copolymer. Amide and sulfogroups of terpolymer don’t form complex compounds in spite of fact that their quantity is larger comparing to carboxylate groups. The complex formed has been revealed to be consisted of three bidentate carboxylate groups Cr(III) : COO– ratio being less or equal to 1:3. The equilibrium between monodentate and bidentate form of carboxylate ligands in the complex compound in an aqueous solution has been discussed.

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The fauna of aquatic insects of Richianka River was studied. 115 species and forms were found. Among them: Plecoptera – 3, Ephemeroptera – 21, Odonata – 17, Trichoptera – 38, Megaloptera – 2, Heteroptera 8 и Coleoptera – 26 species and forms. There are a new species for Byelorussian fauna – Baetis digitatus Bengtsson, 1912. Brachytron pratense (Müller, 1764) and Dytiscus latissimus Linnaeus, 1758 are protected in Belarus. It is concluded that the fauna of aquatic insects is rich and represented by a number of species rare in Belarus and Europe.

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The nucleotide sequence of gene nahG (size 813 bp) which is widespread among natural bacteria Pseudomonas circulating in Belarus was determined in the present paper. Due to the presence of the nucleotide sequences of genes nahG type A88 (presumably localized in the plasmid pA88 of IncP-9 group in bacteria P. fluorescens A88, its sequence is determined and have size 813 bp) and NAH7 (localized in the plasmid NAH7 of IncP-9 group in bacteria Pseudomonas putida NCIB (complete open reading frame is 1305 bp)) made it possible to determine the investigated determinants relevant to type A88. It differs from the known sequence of this type by following nucleotide substitution (it was substitution of thymine to cytosine in 651 position), which led to an additional restriction site for the enzyme RsaI. Identified feature of the gene nahG organization in bacteria P. fluorescens NL61 can be a reliable diagnostic marker in detection of this type of determinants in the analysis of natural and collection naphthalene-utilizing bacteria of the Pseudomonas genus.

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Biochemical properties of the recombinant amylase of Bacillus sp. 1-15 isolate were characterized. Expression of the enzyme in Escherichia coli cells was performed by expression plasmid consisting of the amylase gene. The intracellular extract of E. coli cells was used as source of the enzyme. The enzyme had an optimal temperature at 80 to 90 ºC and an optimal pH of 7 to 9. In the absence of Са2+ions, the amylase of Bacillus sp. 1-15 inactivated by 25 % after 30 min of incubation at 56 ºC. In the presence of 0,2 mM Са2+ ions, the enzyme was active during a long-term incubation at 77 ºC, but rapidly inactivated at temperatures above 84 ºC. The stability of the amylase increased in the presence of Са2+ ions and soluble starch. The amylase activity was significantly prevented by the presence of Co2+, Ni2+, Zn2+, Fe2+, Cu2+ и Cd2+ cations, as well as by EDTA. The enzyme showed an ability to effectively adsorb on granules of raw starch of corn, rice, potato and wheat in rates of 34÷86 %, respectively. In a period of 48 h, the amylase was able to degrade 27÷60 % of glycoside bonds in these starches. The present research showed that amylase from Bacillus sp. 1-15 is characterized by high thermostability, the preference of neutral and slightly alkaline pH values, the stabilization in the presence of Са2+ ions, capability to adsorb and degrade raw starch granules

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Investigations of damaging shrubs gall-forming insects have been conducted in 2002–2012 under condition of green stands in Belarus. Data on taxonomic composition, hosts-plants relations, character of teratogenesis, abundance and geographical distribution of gall-forming insects are given. List of teratogenic insects includes 49 species forming galls on shrubs. Gall-forming insects damage more than 35 species and forms of shrubs from 17 genera and 11 families. List of the most important pests of decorative shrubs includes 16 species: Psylla buxi (Linnaeus, 1758), Saperda populnea (Linnaeus, 1758), Blennocampa phyllocolpa Viitasaari & Vikberg, 1985, Hoplocampoides xylostei (Vallot, 1836), Phyllocolpa leucapsis (Tischbein, 1846), Pontania dolichura (C. G. Thomson, 1871), Pontania proxima (Serville, 1823), Pontania pedunculi (Hartig, 1837), Pontania viminalis (Linnaeus, 1758), Diplolepis eglanteriae Hartig, 1840, Diplolepis spinosissimae Giraud, 1859, Diplolepis rosae (Linnaeus, 1758), Dasineura rosaria (Loew, 1850), Dasineura tetensi (Rübsaamen, 1891), Obolodiplosis robiniae (Haldeman, 1847) and Lasioptera rubi (Schrank, 1803).

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Species composition and ecological structure of carabid beetles (Insecta: Coleoptera: Carabidae) community at cowberry plantations were studied in SW Belarus in the first years after planting. Terrestrial invertebrates were sampled by pitfall traps. A total of 3028 imagines of 45 carabid species have been collected. Activity density of carabid beetles was the highest from late May to early June. Poecilus versicolor (Sturm, 1824) was the most abundant (87,39 %). Species richness of predator and myxophytophagous has been similar (23 and 22 species respectively) but relative abundance differs by 20 times (94,7 % vs. 5,3 %). In the structure of the community is absolutely dominated (98,4 %) by species that are able to burrow into the litter. Carabid communities of cowberry plantations were characterized by dominance of P. versicolor and certain zoophagous species of Pterostichus.

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Peculiarities of stress in barley Hordeum vulgare L. induced by root rot Fusarium sp. were specify for Belarusian varieties Gonar, Dzyvosny and Staly. Stress reaction was assessed by change in length of plants roots, as well by changes in peroxidase activity, lipid peroxidation level and reduced glutathione content in root cells. This is evidenced not only morphometric, and biochemical parameters studied. It was demonstrate that Staly’s plants possess the lower sensitivity to pathogen impact. Their antioxidant system characterized by the absence of peroxidase enzymes induction, higher reduced glutathione and lower lipid peroxidation levels in cells in compare with Gonar’s and Dzivosny’s plants. Mentioned above peculiarities of barley varieties response can be use for artificial selection of plant forms resistant to biotic stress agents. Established features of response of plants can be used for the selection of forms resistant to biotic stress factors.

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The first record of the Needle-grass (Stipa pennata) for the flora of Belarus belongs to 1830 and applies to the territory of the former Minsk province. A little later in 1857 two species Stipa pennata and S. capillata are indicated without precise localities for the former Mogilev province. All these data are not confirmed by herbarium specimens and seems to be erroneous. Other literature sources belong only to the cultivated species. Since 1929, at least 12 species from 6 sections are cultivated in botanical gardens: Stipa capillata L., S. caspia K. Koch, S. caucasica Schmalh., S. extremiorientalis Hara, S. lessingiana Trin. et Rupr., S. pellita (Trin. et Rupr.) Tzvelev, S. pennata L., S. pulcherrima K. Koch, S. sareptana Beck, S. sibirica (L.) Lam., S. tenacissima L., S. ucrainica P. A. Smirn. In this article, European needle-grass – Stipa capillata is reported as alien species for the flora of Belarus for the first time. It was discovered in 2010 in the south-eastern part of the country in the Rogatchev province (Gomel region). A morphological description of the species, short characteristic of the new locality and total distribution are provided. In the discovered locality Stipa capillata occurred most likely as a wool-alien on waste land near the wool-wash enterprise. In Belarus Stipa capillata and potentially a few other species of needlegrasses will probably belong to the group of casual sometimes persisting aliens or can meet as occasional escape from cultivation (or persistent relic of cultivation).

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Sediment cores from lake Uusa from Estonia were eхamined to establish correlations between changes in lake conditions and catchment evolution since the postglacial period. Coring and sampling of the selected sites according to common methodology with the following application of the lithological, isotope (δ18O, δ13C), pollen, radiocarbon (14C), investigations. Common patterns in lake sedimentation and fluctuations, mainly due to the general tendency of climate warming at the beginning of the postglacial epoch and disappearance of permafrost, which led to the increase in infiltrating processes. Lake sedimentation began in territory of the modern catchment area, instead of in a lake hollow as glaciokarst most intensively proceeded on raised sites.

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Lake hollows are the key feature of glacial relief complex. The article proves that evolution of lakes hollows in Belarus is irrevocable and submits to climate change throughout all the Holocene. Consequently the main reason for sedimentation become selective drain processes: there are always some invariants. Lake sedimentation fixes transformation of substance and energy streams. Existence of lakes in Belarus all this period was possible because of plasticity of sedimentation. The article considers two scenarios of lakes lithocomplex buildup and their geographical binding. They describe the sedimentation background. As a result synchronic and diachronic approaches exhibit a sedimentary rhythm. Main through that intensity of its phases change is an inverse function of substance transformation. Therefore lakes possess sufficient stability if they don’t only accumulate autigeneous silts but also are lying near upper courses of reservoirs with typical zone biomes.

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Method of land covers computer-aided interpretation of Landsat satellite data according to European nomenclature CORINE Land Cover (the first level) is tested and adapted for Belarus’s environment (on the example of territory of Volozhin district, Minsk region). In fact results of processing reveal trends of land recourses dynamics from 1975 to 2010 years. This period is divided into three main stages (1975–1995, 1995–2005, 2005–2010), which illustrates changes of resource management character as well as changes in social and political settings all over the country. To sum up the complex of actions is suggested for land use optimization. In particular monitoring by Belarusian satellite and processing of its data (according to European nomenclature CORINE Land Cover) can be used as a way to improve efectiveness of land use.

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The article is devoted to the economic and geographical analysis of the demographic development of the Belarusian-Russian border region (for example districts of the Belarusian side of the border). The trends of population dynamics, natural movement and migration of the population for 1989–2009 years for the districts of the three spatial orders: 1) immediately adjacent to the state border; 2) in the zone of the regional center influence; 3) peripheral by the economic and geographical position are analyzes in the article. The typology of Belarusian border regions according to the factors of the demographic balance forming is developed in the article. It is found that demographic space of the Belarusian-Russian border is heterogeneous, has center-peripheral properties with the peripheral priority and characterized by: 1) a regressive population dynamics based on the prevalence of natural population decrease over the migration outflow, 2) the most favorable parameters of demographic development of the border areas in the zone of the regional center influence.

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The executed researches are based on the calculation of private and integrated ecological and climatic indicators of the environment which the degree of comfort for the human community are characterized. There are 4 categories of climatic conditions comfort in the cities of Belarus: comfortable, moderately comfortable, a lowcomfortable, discomfortable. Minsk climate comfort evaluation was carried out on the average daily meteorological data (temperature and relative humidity, partial pressure of water vapor, wind speed, atmospheric pressure air, precipitation, total cloud cover and fogs) during 25-year period. The results analysis showed that in Minsk has been a steady upward trend in the number of days with normally equivalent-effective air temperature from 17 to 21 ºC, average temperature in July and January, a slight increase of total cloud cover and amount of stuffy days, the duration of comfortable period of residential buildings use, the integral index of comfort climate increase during 1984–2008. The downward trend is typical for: duration of the cold stress Hill’s index ≥4,5 W/m2·s, the number of cases with contrasting weather changes; the number of days: with from-day-to-day changes in atmospheric pressure ≥9 hPa/day, with a relative humidity ≥80 %, with temperatures ≤ –10 ºC, days with uncomfortable total cloud cover ≥6 points, with wind velocities ≥5 m/s, with precipitation ≥1 mm; climatic atmosphere’s self-cleaning capacity. There were two prevailing categories of climatic conditions during study period: moderately comfortable (48 %) and low-comfortable (40 %). Comfortable climatic conditions observed in 2000, 2002 and 2005. Forecast scenario suggests an increased level of Minsk climate comfort until 2020. The results of studies designed for use in the planning and design of environmental management for sustainable development of Minsk and optimization of its inhabitants living environment.

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A phenomenon anticyclogenez and its effect on the extremes of temperature. Particular attention is paid to patterns of development, the general classification and geographical spread of anticyclons. Term paper contains information about the frequency and duration of anticyclons in the territory of Belarus. In this article is demonstrated anticyclons influence to forming of extreme weather phenomena. In different seasons they create positive or negative temperature and precipitation anomalies. Prolonged anticyclone activity leads to droughts and extremely cold winters. Anticyclons explored thanks to synoptical maps in a period since 1980 to 2009. It permitted to get important statistic information for exploration of anticyclonic weather type in the territory of Belarus. Considerated the example of continental anticyclons influence to weather anomalies that were observed above the Eastern Europe in July – August 2010. Cause of unusual heat and drought is a giant and high (more than 16 km) anticyclon that blocked the way to western wind usually takes place in this elevations and received a stable condition.

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Peculiarities of glaciomorphology of Gorodok elevation, located in the north-east of Belarus were studied. Geological factors that influenced the building of modern relief were pointed out. Uneven-aged relief of the elevation is found. Peculiarities that are characteristic for the relief of different slopes of the elevation are noted. The conclusion is made that Gorodok elevation is an icedividing medial morainic elevation in the centre with marginal formations in the north, that were formed out during the Orsha and Braslav stages of Pooserje glaciation.

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