МАТЕМАТИКА И ЕСТЕСТВЕННЫЕ НАУКИ

Das vorliegende Lehrmittel umfasst fünf Lektionen, jede davon enthält eine Reihe von Fachausdrücken, spezieller Lexik und Vorübungen. Der Haupttext, Aufgaben dazu, Nachtext, sowie lexikalische und grammatikalische Übungen dienen zur Entwicklung der kommunikativen Kompetenz in beruflichen Sprachtätigkeit von Doktoranden. Texte zur Kontrollübersetzung und Testen ermöglichen die Kontrolle der erworbenen Fertigkeiten und Fähigkeiten.

The aim of the work was to investigate the influence of pruning on wood composition in different morphological parts of the Norway spruce (Picea abies (L.) Karst.) trees, including heartwood and sapwood compared to normal trees as a reference. Pruning intensity during that treatment was 35–41 % of the total length of the crown for the trees with the average and less than average diameter at breast height and 28 % for the trees with diameter at breast height higher than the average. Components composition of acetone soluble extractives was analysed by gas chromatography with long and short columns, and their molar mass distribution was analysed by gel permeation chromatography. The following was determined in the pre-extracted wood tissues: cellulose (acid hydrolysis – gas chromatography); lignin (Acetyl Bromide method) and hemicellulose and pectins composition (acid methanolysis – gas chromatography). Acetone-soluble wood extractives are a complex mixture of different groups of organic compounds, i.e. both lipophilic and polar substances. The high-performance gel permeation chromatography analysis revealed the dominance of triglycerides, steryl esters, fatty and resin acids in the obtained extracts. The amount of monosaccharides in the extracts was also substantial. The chemical composition of wood tissues of the reference and pruned trees was almost similar. Compared to the reference trees, the wood samples of the pruned trees showed increased amounts of resin acids in sapwood, high amounts of lignin and double amounts of fructose in both sapwood and heartwood. The analysis results can be explained by response of trees to their pruning as a defense mechanism against plant pathogens and must be a result of the current physiological activity of those trees, possibly related to differences in crown sizes. For citation: Pranovich A.V., Antonov O.I., Dobrovolsky A.A. Pruning Influence on Chemical Composition of Spruce Wood (Picea abies (L.) Karst.). Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 3, pp. 145–160. DOI: 10.37482/0536-1036-2021-3-145-160
Цель исследования – изучение влияния обрезки ветвей на химический состав древесины ели европейской (Picea abies (L.) Karst), включая ядровую древесину и заболонь. В качестве контрольной использовалась древесина деревьев, не подвергнутых обрезке. Интенсивность удаления части ветвей составляла: 35–41 % от общей длины кроны – у деревьев со средним и менее среднего диаметром на высоте груди и 28 % – у деревьев с диаметром выше среднего. Компонентный состав растворимых в ацетоне экстрактивных веществ был проанализирован посредством газовой хроматографии на длинной и короткой колонках, молярно-массовое распределение найдено с помощью гель-проникающей хроматографии. В предварительно экстрагированных образцах древесины определяли содержание целлюлозы (кислотный гидролиз – газовая хроматография), лигнина (метод ацетилбромида) и состав гемицеллюлоз и пектиновых веществ (кислотный метанолиз – газовая хроматография). Растворимые в ацетоне экстрактивные вещества древесины представляют собой сложную смесь различных групп органических соединений, включая липофильные и полярные вещества. Анализ полученных экстрактов с использованием гель-проникающей хроматографии выявил преобладание в них триглицеридов, стериловых эфиров, жирных и смоляных кислот, а также значительного количества моносахаридов. Химический состав древесных тканей контрольных деревьев и деревьев из опыта был схож. Однако по сравнению с первыми древесина вторых характеризовалась повышенным количеством смоляных кислот в заболони, высоким количеством лигнина и в два раза большим уровнем фруктозы как в заболони, так и в ядровой древесине. Такие результаты можно объяснить реакцией деревьев на обрезку ветвей и воздействием патогенов (т. е. срабатыванием защитного механизма растения). Полученные данные также являются отражением физиологической активности обследованных деревьев и, возможно, связаны с различиями в размере их крон. Для цитирования: Pranovich A.V., Antonov O.I., Dobrovolsky A.A. Pruning Influence on Chemical Composition of Spruce Wood (Picea abies (L.) Karst.) // Изв. вузов. Лесн. журн. 2021. № 3. С. 145–160. DOI: 10.37482/0536-1036-2021-3-145-160.

The study was conducted at the Botanical Garden of Petrozavodsk State University (middle taiga sub-zone). The subjects of the study were an indigenous species (P. abies (L.) Karst.), and five introduced species (P. pungens Engelm. f. glauca Regel., P. pungens Engelm. f. viridis Regel., P. glauca (Mill.) Britt., P. omorica (Pane) Purk., P. mariana Britt., P. obovata Ledeb.). The study established high variability of the isoperoxidase spectrum in the Picea species needles during the circannual cycle. Molecular forms of peroxidase typical for growth and dormant periods were determined. Some Picea species were found to have isoenzymes appearing only during the deep dormant period. An increase in the heterogeneity of the needles isoperoxidase spectrum and appearance of molecular forms of the enzyme typical for the dormant period were observed in the indigenous and introduced Picea species in the course of adaptation to unfavorable winter conditions. The isoenzyme system rearrangement ensures plants tolerance to external factors and homeostasis regulation. The content of chlorophyll and carotenoids in the needles of the studied species undergoes significant seasonal changes and is largely determined by their biological characteristics. Pigments concentration naturally increases by the end of the vegetative period and decreases slightly in winter. The total number of pigments in the needles of the indigenous and introduced species is almost the same, indicating a similar rate of stock formation. By the dormant period, the ratio of chlorophylls to carotenoids increases and reaches approximately the same level in all Picea species. The Picea species introduced in Karelia adapt to low winter temperatures with the same physiological changes as the indigenous ones. These include changes in the isoenzyme composition of peroxidase, the dynamics of the pigments content in the needles, and the ratio of chlorophylls to carotenoids. Potential tolerance of the studied plant species to unfavorable environmental factors is affected by the extreme factor of tension that does not exceed the threshold value

In this paper, we summarise material pertaining to the distribution and habitat preference of Bombus (Kallobombus) soroeensis (Fabricius, 1777) on the territory of Arkhangelsk Region. B. soroeensis is widely represented on the territory as nominative subspecies B. soroeensis ssp. soroeensis, which is common mainly in Fennoscandia, the British Isles and Eastern Europe. The northern border of the species range in the Arkhangelsk Region is the lower reaches of the Mezen River, located in the transition zone between the northern taiga and the forest-tundra. This locality is probably one of the most northern records of this species in the northern part of the Russian Plain. In Eastern Fennoscandia, B. soroeensis is distributed far to the north, i.e., in the northern parts of Finland and Norway. In relation to the habitat preference, B. soroeensis in the study region belongs to the category of meadow species. This species is typical of different types of meadows and ruderal habitats. B. soroeensis is not typical with regards to the native taiga habitats, in most cases. This is similar to the situation on the territory of Finland, where this species is associated with open meadow habitats. Individuals of B. soroeensis have been recorded on a wide range of entomophilous plants, and the main examples are Rhinanthus minor, Epilobium angustifolium, Cirsium arvense, Scorzoneroides autumnalis, Lotus corniculatus.

This study contains findings of research carried out at the Botanical Garden of Petrozavodsk State University (South Karelia, central taiga subzone) in April – October in the period from 1986 to 2012. The subjects of the studies were introduced plants of three species of Malus Mill.: dwarf apple – Malus baccata (L.) Borkh., wild apple – Malus sylvestris Mill., and Niedzwetzky’s apple – Malus niedzwetzkyana Dieck. ex Koehne. Phenological observations were carried out once in 3 days by the N. Bulygin technique (1979). The phenophase was considered to have occurred if it was observed in at least 30% of the shoots of all specimens of the species under study. All samples were checked for compliance with the normal probability law. The correlation coefficients and differences between the mean values were verified to determine their reliability. Elementary statistics obtained demonstrate, among other things, that the experiment’s accuracy rate is fairly high (4–6%), while the variation coefficient is small (18–22%). It was found that M. baccata trees begin and end most of their phenophases approximately 5–10 days earlier than the other studied species. Furthermore, in the beginning and middle of the growing period, phonological phases of M. baccata proceed at colder weather compared to the other studied Malus species. At the end of the growing period, these differences among the species level off. Of all the studied climatic factors, air temperature has the most measurable positive influence on the development of Malus species in Karelia. Daily average air humidity and precipitation have a less prominent influence on еру phenophases of the studied Malus species. The course and strength of such influence depend on the peculiarities of the phenophase itself. All the studied introduced Malus species show a high degree of introduction prospect (82−93 points) and can be successfully used in Karelia for gardening and landscaping purposes.

Сформулирован метод численного решения двумерного нестационарного кинетического уравнения переноса, записанного в сферической системе координат. Конечноразностная аппроксимация уравнения выполнена на неортогональных четырехугольных пространственных сетках, строится по схеме с дополнительными соотношениями и является консервативной. Для решения полученной системы сеточных уравнений разработан алгоритм, основанный на методе бегущего счета. Приводятся результаты тестирования данного метода на одномерной задаче с источником

Для уравнения переноса, записанного в цилиндрической системе координат, построена характеристическая схема. Схема включает в себя два этапа. На первом этапе в счетной ячейке строится обыкновенное дифференциальное уравнение баланса частиц, с помощью которого находится полный поток частиц на неосвещенной поверхности ячейки. На втором этапе по схеме типа DSn-метода происходит распределение выходящего потока частиц по неосвещенным граням ячейки

Abstract. LaNi4,3–xCoxMn0,4Al0,3 materials (x=0, 0.25, 0.5, 0.75, 1.0) were prepared and examined using XRD technique. Ingot electrodes were formed from these materials for electrochemical studies, namely cyclic voltammetry with different scanning rates n (mV/s). A determination of surface capacity QS of the ingot electrodes was carried out with an extrapolation to infinite scan rate, taking into account the polarisation direction as charging or discharging. The thickness of superficial active layer dS was calculated from QS values. Based on the variation of QS and dS according to variation of Co ratio x, it is found that there are two suitable Co ratios corresponding to two opposite processes: charging and discharging.

In hydraulic control components (directional control valves, servo valves, LS regulators, etc.) there is a problem of determining of flow rate through the radial clearances of different lengths overlap between the control piston and body of component. As lengths of overlap are relatively small, it is necessary to analyze the development of a full profile of fluid velocity through radial clearance (in sleep mode servo valve has length of overlap equal zero; directional control valves, depending on the diameter, have lengths of overlaps of 0.6 to 0.8 mm; while in work of the load sensing (LS) regulator, piston is continuously located in areas of small opening, zero overlap and small length of overlap). Common values of radial clearance is approximate in the range from 1 ȝm (minimum values for servo valves) to 50 ?m (maximum value for axial piston pumps). In this paper is analyzed development of full-length profile of velocity inside radial clearance (i.e. development of boundary layer) and derived an expression for the flow rate through the so-called long radial clearances, taking into account the influence the changes of thermodynamic state of hydraulic oil on the value of viscosity. Under the long radial clearances implies such clearances where they can be ignored the impact of the development of full-length profile of velocity on flow rate through clearance and change of thermodynamic state of the oil considered isothermal.

В. Брунс и И. Губеладзе ввели аналог алгебраической K-теории, в котором K-группы дополнительно параметризованы многогранниками определенного типа. Для изучения K-групп многогранников высокой размерности предлагается использовать понятие стабильной E-эквивалентности.

С использованием теории функционала плотности исследовано взаимодействие тетрафенилпорфирина с инициатором радикальной полимеризации - пероксидом бензоила. Установлена структура образующегося между ними комплекса с переносом заряда и проанализированы причины ускоряющего влияния порфирина на распад пероксида в условиях полимеризации метилметакрилата.

Учебное пособие предназначено для студентов отделения "Экология", изучающих немецкий язык. Работа с пособием создает базу, которая позволяет будущему специалисту понимать литературу по своей специальности на немецком языке, отбирать полезную для работы информацию, переводить тексты или выдержки из них на русский язык.