486 research outputs found

    Planning the forest transport systems based on the principles of sustainable development of territories

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    The article identifies a new method of dynamic modeling in the design of the transport system in the forest fund (TSFF), which is based on economic and mathematical modeling and fuzzy logic tools. The combination of the indicated methods is designed to reduce the disadvantages of their use and increase the benefits. The article substantiates the choice of assessing the forecast level of the impact of risks on the activities of forestry enterprises (the method of expert assessments), using the methodological tools of fuzzy logic. The indicated method makes it possible to take into account a large variety of risk factors of the internal and external environment. At the same time, methodological aspects of fuzzy logic make it possible to formulate a quantitative assessment of qualitative indicators. The article substantiates the choice of tools for economic and mathematical modeling in order to state the design problem of the planned TSFF. Since the indicated method enables the formalization of the functioning of the timber transport system in the given conditions. The article presents a developed model that correctly takes into account the influence of risk factors when planning a TSFF, through the combination of fuzzy logic methods and economic and mathematical modeling. The advantages of the developed model include: considering the multivariance of material flows, vehicles, points of overload, etc.; automated processing of input parameters and effective data; using the model for forecasting, i.e. the possibility of deriving a fuzzy estimate of the efficiency of the timber transport system by identifying cause-effect relationships between the modeling object and the influence of risk factors on its functioning. © 2019 IOP Publishing Ltd

    E2 strengths and transition radii difference of one-phonon 2+ states of 92Zr from electron scattering at low momentum transfer

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    Background: Mixed-symmetry 2+ states in vibrational nuclei are characterized by a sign change between dominant proton and neutron valence-shell components with respect to the fully symmetric 2+ state. The sign can be measured by a decomposition of proton and neutron transition radii with a combination of inelastic electron and hadron scattering [C. Walz et al., Phys. Rev. Lett. 106, 062501 (2011)]. For the case of 92Zr, a difference could be experimentally established for the neutron components, while about equal proton transition radii were indicated by the data. Method: Differential cross sections for the excitation of one-phonon 2+ and 3- states in 92Zr have been measured with the (e,e') reaction at the S-DALINAC in a momentum transfer range q = 0.3-0.6 fm^(-1). Results: Transition strengths B(E2;2+_1 -> 0+_1) = 6.18(23), B(E2; 2+_2 -> 0+_1) = 3.31(10) and B(E3; 3-_1 -> 0+_1) = 18.4(11) Weisskopf units are determined from a comparison of the experimental cross sections to quasiparticle-phonon model (QPM) calculations. It is shown that a model-independent plane wave Born approximation (PWBA) analysis can fix the ratio of B(E2) transition strengths to the 2+_(1,2) states with a precision of about 1%. The method furthermore allows to extract their proton transition radii difference. With the present data -0.12(51) fm is obtained. Conclusions: Electron scattering at low momentum transfers can provide information on transition radii differences of one-phonon 2+ states even in heavy nuclei. Proton transition radii for the 2+_(1,2) states in 92Zr are found to be identical within uncertainties. The g.s. transition probability for the mixed-symmetry state can be determined with high precision limited only by the available experimental information on the B(E2; 2+_1 -> 0+_1) value.Comment: 14 pages, 5 figures, submitted to Phys. Rev. C, revised manuscrip

    Guardianship for Popular Sobriety in Russia at the Beginning of 20th Century: from Wine Monopoly to “Dry Law”

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    The article is devoted to the guardianship of popular sobriety — institutions created by the government of the Russian Empire at the end of the 19th century to organize the fight against excessive alcohol consumption at the provincial and district levels. The study describes the situation with the consumption of alcoholic beverages in Russia at the turn of the XIX—XX centuries, provides the main provisions of the state wine monopoly, introduced in 1895 with the direct participation of the Minister of Finance S. Yu. Witte. Based on the Charter of Guardianship of People’s Sobriety, the authors describe their powers, composition, and features of work organization. Based on the analysis of diverse sources (including unpublished archival sources), the article characterizes the diverse activities of guardianship in Russia at the beginning of the 20th century, as well as its assessment by contemporaries. The conclusion is made about the relatively low efficiency of the work of sober institutions due to their bureaucracy and insufficient funding. The article describes the problem of reforming the guardianship, which was discussed with varying intensity in the 1900—1910s in the Ministry of Finance, the State Council, public and zemstvo circles. Special attention is paid to the analysis of the problems faced by the guardianship of popular sobriety during the First World War after the introduction of the “Prohibition”. The scientific novelty of the research lies in an attempt to analyze the entire set of issues related to the activities of guardianship in the period under review, starting from documents of a legal and office-work nature, statistical materials, periodicals, journalistic and memoir literature

    Trophic effects of sponge feeding within Lake Baikal\u27s littoral zone .2. Sponge abundance, diet, feeding efficiency, and carbon flux

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    Endemic freshwater demosponges in the littoral zone of Lake Baikal, Russia, dominate the benthic biomass, covering 44% of the benthos. We measured in situ sponge abundance and,orating and calculated sponge-mediated Fluxes of picoplankton (plankton \u3c2 mu m) for two common species, Baikalospongia intermedia and Baikalospongia bacillifera. By means of dual-beam how cytometry, we found retention efficiencies ranging from 58 to 99% for four types of picoplankton: heterotrophic bacteria, Synechococcus-type cyanobacteria, autotrophic picoplankton with one chloroplast, and autotrophic picoplankton with two chloroplasts. By using a general model for organism-mediated fluxes, we conservatively estimate that through active suspension feeding, sponges are a sink for 1.97 g C d(-1) m(-1), mostly from procaryotic cell types. Furthermore, grazing by these extensive sponge communities can create a layer of picoplankton-depleted water overlying the benthic community in this unique lake

    Використання аліфатичних альдегідів у синтезі нових 1H-2,1-бензотіазин-4-он 2,2-діоксидів, конденсованих з пірановим ядром за допомогою доміно-взаємодій. Антимікробна активність синтезованих сполук

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    Domino-type Knoevenagel-Michael-hetero-Thorpe-Ziegler and Knoevenagel-hetero-Diels-Alder interactions using 1-ethyl-1H-2,1-benzothiazin-4(3H)-one 2,2-dioxide and aliphatic aldehydes as initial compounds have been studied. These reactions have led to 2-amino-3-cyano-4H-pyran and 2H-3,4-dihydropyran derivatives, respectively. It has been shown that the three-component one-pot interaction of 1-ethyl-1H-2,1-benzothiazin-4(3H)one 2,2-dioxide with saturated aliphatic aldehydes and malononitrile proceeds under rather mild conditions and results in formation of 2-amino-6-ethyl-4-alkyl-4,6-dihydropyrano[3,2-c][2,1]benzothiazin-3-carbonitrile 5,5-dioxides with moderate and high yields. At the same time, the yields of target products decrease with the increase of the length of the aliphatic aldehyde carbon chain. In this regard, the use of citronellal allowed us to obtain the product of the three-component interaction with a low yield. To date, there is no information in the literature about the possible application of aliphatic dialdehydes in such three-component interactions. It has been found that the use of glutaric aldehyde results in the synthesis of a new class of bis-derivatives of 2-amino-4H-pyran, in which two fragments are linked by the polymethylene bridge. The use of α,β-unsaturated aldehydes in the three-component interaction with 1-ethyl-1H-2,1-benzothiazin-4(3H)-one 2,2-dioxide and malononitrile was accompanied by decrease in the process efficiency compared to saturated aliphatic aldehydes. The target fused 2-amino-3-cyano-4H-pyran was obtained only when α-methylcinnamic aldehyde was used in the reaction. A two-component interaction of 1-ethyl-1H-2,1-benzothiazin-4(3H)-one 2,2-dioxide with citronellal has been also studied. It has been shown that this reaction is stereospecific. It proceeds through domino Knoevenagel-heteroDiels-Alder sequence resulting in a new heterocyclic system – 2,2a,3,4,5,6,6a,8-octahydroisochromeno[4,3-c] [2,1]benzothiazine 7,7-dioxide. The study of the antimicrobial activity of the compounds synthesized has allowed finding compounds with a moderate activity against P. aeruginosa і C. albicans.Изучены домино-взаимодействия Кневенагеля-Михаэля-гетеро-Торпа-Циглера и Кневенагеля-гетеро-Дильса-Альдера с участием 1-этил-2,1-бензотиазин-4(3Н)-он 2,2-диоксида и алифатических альдегидов, приводящих соответственно к образованию производных 2-амино-3-циано-4Н-пирана и 2Н-3,4-дигидропирана. Показано, что трехкомпонентное одностадийное взаимодействие 1-этил-2,1-бензотиазин-4(3Н)-он 2,2-диоксида с насыщенными алифатическими альдегидами и малонодинитрилом протекает в очень мягких условиях и приводит к образованию 2-амино-6-этил-4-алкил-4,6-дигидропирано[3,2-c][2,1]бензотиазин-3-карбонитрил 5,5-диоксидов с высокими и умеренными выходами. В то же время увеличение длины углеродной цепи алифатических альдегидов приводит к уменьшению выхода целевых продуктов. Так, при использовании цитронеллаля продукт трехкомпонентного взаимодействия удалось получить только с невысоким выходом. Алифатические диальдегиды не были ранее использованы в данных взаимодействиях; показано, что применение глутарового альдегида приводит к новому классу бис-производных 2-амино-4Н-пирана, в котором фрагменты соединены полиметиленовым мостиком. Использование α,β-ненасыщенных альдегидов в трехкомпонентном взаимодействии с 1-этил-2,1-бензотиазин-4(3Н)-он 2,2-диоксидом и малонодинитрилом сопровождалось уменьшением эффективности процесса по сравнению с насыщенными алифатическими альдегидами. Целевой продукт взаимодействия конденсированный 2-амино-3-циано-4Н-пиран был получен только в случае применения α-метилкоричного альдегида. Изучено взаимодействие между 1-этил-2,1-бензотиазин-4(3Н)-он 2,2-диоксидом и цитронеллалем; показано, что данная реакция протекает исключительно как стерео-специфичное домино-взаимодействие Кневенагеля-гетеро-Дильса-Альдера и приводит к образованию новой гетероциклической системы – 2,2a,3,4,5,6,6a,8-октагидроизохромено[4,3-c][2,1]бензотиазин 7,7-диоксида. Изучение антимикробной активности синтезированных соединений позволило обнаружить производные, проявляющие умеренную активность против P. aeruginosa и C. albicansВивчені доміно-взаємодії Кньовенагеля-Міхаеля-гетеро-Торпа-Ціглера та Кньовенагеля-гетеро-Дільса-Альдера за участю 1-етил-1Н-2,1-бензотіазин-4(3Н)-ону 2,2-діоксиду та аліфатичних альдегідів, що приводять до утворення відповідно похідних 2-аміно-3-ціано-4Н-пірану та 2Н-3,4-дигідропірану. Показано, що трикомпонентна одностадійна взаємодія 1-етил-1Н-2,1-бензотіазин-4(3Н)-ону 2,2-діоксиду з насиченими аліфатичними альдегідами і малонодинітрилом перебігає у дуже м’яких умовах і приводить до утворення 2-аміно-6-етил-4-алкіл-4,6-дигідропірано[3,2 c][2,1]бензотіазин-3-карбонітрил 5,5-діоксидів з високими та помірними виходами. У той же час збільшення довжини вуглецевого ланцюга аліфатичного альдегіду приводить до зменшення виходу цільових продуктів. Так, при використанні цитронелалю продукт трикомпонентної взаємодії вдалося одержати тільки з невисоким виходом. Аліфатичні діальдегіди не були раніше використані у даних взаємодіях; показано, що використання глутарового альдегіду дозволяє отримати новий клас біс-похідних 2-аміно-4Н-пірану, в якому фрагменти з’єднані поліметиленовим містком. Використання α,β-ненасичених альдегідів у трикомпонентній взаємодії з 1-етил-1Н-2,1-бензотіазин-4(3Н)-ону 2,2-діоксидом і малонодинітрилом супроводжувалося зменшенням ефективності процесу в порівнянні з насиченими аліфатичними альдегідами. Цільовий продукт взаємодії конденсований 2-аміно-3-ціано-4Н-піран був отриманий тільки у випадку застосування α-метилкоричного альдегіду. Вивчена взаємодія між 1-етил-1Н-2,1-бензотіазин-4(3Н)-ону 2,2-діоксидом і цитронелалем; показано, що така реакція перебігає винятково як стереоспецифічна доміно-взаємодія Кньовенагеля-гетеро-Дільса-Альдера і приводить до утворення нової гетероциклічної системи – 2,2a,3,4,5,6,6a,8-октагідроізохромено[4,3-c][2,1]бензотіазин 7,7-діоксиду. Вивчення антимікробної активності синтезованих сполук дозволило виявити похідні, що проявляють помірну активність проти P. aeruginosa і C. albicans

    Consistent alpha-cluster description of the 12C (0^+_2) resonance

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    The near-threshold 12C (0^+_2) resonance provides unique possibility for fast helium burning in stars, as predicted by Hoyle to explain the observed abundance of elements in the Universe. Properties of this resonance are calculated within the framework of the alpha-cluster model whose two-body and three-body effective potentials are tuned to describe the alpha - alpha scattering data, the energies of the 0^+_1 and 0^+_2 states, and the 0^+_1-state root-mean-square radius. The extremely small width of the 0^+_2 state, the 0_2^+ to 0_1^+ monopole transition matrix element, and transition radius are found in remarkable agreement with the experimental data. The 0^+_2-state structure is described as a system of three alpha-particles oscillating between the ground-state-like configuration and the elongated chain configuration whose probability exceeds 0.9
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