Щодо розрахунку деформацій зсуву в призматичних стержнях із полімерних матеріалів за умов розтягу з крученням

The process of creep of prismatic rods made of linear-viscoelastic polymeric materials under combined loading is considered. Defining equations that determine the relationship between strains, stresses and time are given in the form of a superposition of shear and bulk strain. The object of study is prismatic bars made of fiberglass ST-1. The area of linearity of the model is substantiated on the basis of the hypothesis of the existence of the creep function, which is built on the yield curves, a single diagram of long-term deformation and the statistical value of the quantile of statistics. The region of linear-elastic deformation is recognized based on the fulfillment of the condition of existence of a single creep function. The defining equations of the model contain a set of functions and coefficients determined from the basic experiments. On the basis of the relations between the kernels of the one-dimensional stress state, the parameters of the kernels under the condition of a complex stress state are determined. The linearity of viscoelastic properties is given by the Boltzmann-Voltaire equations. The fractional-exponential kernels of heredity are chosen as the kernels of heredity. The obtained values of the core parameters are used to calculate the creep deformations of prismatic bars made of ST-1 fiberglass under conditions of simultaneous tensile tension. Pages of the article in the issue: 115 - 118 Language of the article: UkrainianРозглядається процес повзучості призматичних стержнів з лінійно-в’язкопружних полімерних матеріалів за умов комбінованого навантаження. Визначальні рівняння, що описують залежність між деформаціями, напруженнями і часом, задаються у вигляді суперпозиції зсувної і об’ємної деформації. Об’єктом дослідження являються призматичні стержні зі склопластику СТ-1. Обґрунтовується область лінійності моделі, виходячи з гіпотези існування функції повзучості, побудованої по кривим податливості, єдиної діаграми довготривалого деформування і статистичного значення квантиля статистики. Визначається область лінійно-пружного деформування, виходячи з виконання умови існування єдиної функції повзучості. Визначальні рівняння моделі містять набір функцій і коефіцієнтів, що знаходяться з базових експериментів. На підставі співвідношень між ядрами одновимірного напруженого стану визначаються параметри ядер за умови складного напруженого стану. Лінійність в'язкопружних властивостей задається рівняннями Больцмана-Вольтера з дробово-експоненціальним ядром спадковості. Отримані значення параметрів ядер використовуються для розрахунку деформацій повзучості призматичних стержнів зі склоапластика СТ-1 за умов одночасної дії розтягу з крученням

The use of SSR-markers in rice breeding for resistance to blast and submergence tolerance

Received: March 16th, 2022 ; Accepted: July 20th, 2022 ; Published: September 6th, 2022 ; Correspondence: [email protected] identification of effective specialized DNA markers providing the clear control of target locus inheritance by the trait of submergence tolerance has been conducted. Among the studied set of microsatellite markers, two the most informative SSR-markers - RM 7481, PrC3 showed high efficiency in detecting intraspecific polymorphism of rice varieties and lines used in the work. With the use of these markers the clear genotype marking the obtained hybrid rice plants by this trait has been conducted and it is has been verified by phenotype evaluation as a result of laboratory trials. The plant samples carrying the target gene in heterozygous and homozygous state has been selected. About 400 backcrossed self-pollinated rice lines with introgressed and pyramided resistance genes Pi-1, Pi-2, Pi-33, Pi-ta, Pi-b to Pyricularia oryzae Cav. were obtained within the frameworks of program to develop genetic rice sources resistant to blast. The conducted testing for resistance to blast and the assessment by economically valuable traits have allowed to select the prospective rice samples. The plant samples of F2 and BC1F1 generations with combination of resistance to blast genes (Pi) and submergence tolerance gene (Sub1A) in homozygous and heterozygous state that is confirmed be the results of analysis of their DNA have been obtained. The obtained hybrid plants are being tested in breeding nurseries for a complex of economically valuable traits. The best plants will be selected and send to State Variety Testing system. Their involving in rice industry will reduce the use of plant protection chemicals against diseases and weeds, thereby increasing the ecology status of the rice industry

Properties of low-lying states in some high-nuclearity Mn, Fe and V clusters: Exact studies of Heisenberg models

Using an efficient numerical scheme that exploits spatial symmetries and spin parity, we have obtained the exact low-lying eigenstates of exchange Hamiltonians for the high nuclearity spin clusters, Mn_{12}, Fe_8 and V_{15}. The largest calculation involves the Mn_{12} cluster which spans a Fock space of a hundred million. Our results show that the earlier estimates of the exchange constants need to be revised for the Mn_{12} cluster to explain the level ordering of low-lying eigenstates. In the case of the Fe_8 cluster, correct level ordering can be obtained which is consistent with the exchange constants for the already known clusters with butterfly structure. In the V_{15} cluster, we obtain an effective Hamiltonian that reproduces exactly, the eight low-lying eigenvalues of the full Hamiltonian.Comment: Revtex, 12 pages, 16 eps figures; this is the final published versio

On the possibility of magneto-structural correlations: detailed studies of di-nickel carboxylate complexes

A series of water-bridged dinickel complexes of the general formula [Ni<sub>2</sub>(μ<sub>2</sub>-OH<sub>2</sub>)(μ2- O<sub>2</sub>C<sup>t</sup>Bu)<sub>2</sub>(O<sub>2</sub>C<sup>t</sup>Bu)2(L)(L0)] (L = HO<sub>2</sub>C<sup>t</sup>Bu, L0 = HO<sub>2</sub>C<sup>t</sup>Bu (1), pyridine (2), 3-methylpyridine (4); L = L0 = pyridine (3), 3-methylpyridine (5)) has been synthesized and structurally characterized by X-ray crystallography. The magnetic properties have been probed by magnetometry and EPR spectroscopy, and detailed measurements show that the axial zero-field splitting, D, of the nickel(ii) ions is on the same order as the isotropic exchange interaction, J, between the nickel sites. The isotropic exchange interaction can be related to the angle between the nickel centers and the bridging water molecule, while the magnitude of D can be related to the coordination sphere at the nickel sites

ДНК-технологии (молекулярное маркирование) в селекции томата на устойчивость к Tobacco Mosaic Virus

Relevance. The purpose of this work is to create new discrete competitive tomato genotypes based on modern biotechnological approaches with increased resistance to the tobacco mosaic virus, economically valuable traits and adapted to the soil and climatic conditions of cultivation in the southern regions of the Russian Federation.Methods. At the first stage of the study, SSR markers taken from literature sources were tested [1;2] and PCR conditions were optimized for the identification of target Tm genes (Tm2a, Tm22, providing resistance to tobacco mosaic virus at the tissue level) in the breeding material available in the department of vegetable and potato growing.Results. Two informative molecular markers Tms 37 and UMD 2060 were selected, which reveal the allelic difference between resistant and susceptible samples. Hybridization of FMS tomato lines with samples having the desired genes of interest in the genotype for obtaining tomato lines resistant to TMV was carried out. Seeds of paternal forms - donors of target genes were obtained for their further use in breeding work. The scientific novelty lies in the study of the discrete genetic material of Solanumlycopersicum, used in the breeding process, and preserving its functions in a new genetic environment.Актуальность. Целью данной работы является создание на основе современных биотехнологических подходов (молекулярное маркирование) новых конкурентоспособных генотипов томата с повышенной устойчивостью к вирусу табачной мозаики, хозяйственно-ценными признаками и адаптированных к почвенно-климатическим условиям выращивания в южных регионах РФ.Материал и методика. На первом этапе исследования выполнена апробация SSR-маркеров, взятых из литературных источников [1;2] и оптимизированы условия ПЦР для идентификации целевых генов Tm (Tm2a, Tm22, обеспечивающих устойчивость к вирусу табачной мозаики на тканевом уровне) в селекционном материале, имеющемся в отделе овощекартофелеводства.Результаты. Отобрано два информативных молекулярных маркера Tms 37 и UMD 2060, которые выявляют аллельную разницу между устойчивыми и восприимчивыми образцами. Проведена гибридизация ФМС-линий томата с образцами, имеющими в генотипе искомые гены интереса для получения резистентных к ВТМ линий томата. Получены семена отцовских форм – доноров целевых генов для дальнейшего их использования в селекционной работе. Научная новизна заключается в изучении дискретного генетического материала Solanum lycopersicum, используемого в селекционном процессе и сохраняющего свои функции в новом генетическом окружении

Hydrocarbon Oxidation with H2O2, Catalyzed by Iron Complexes with a Polydentate Pyridine-Based Ligand

Metals in Catalysis, Biomimetics & Inorganic Material

Cluster in the Auroral Acceleration Region

Due to a fortuitous evolution of the Cluster orbit, the Cluster spacecraft penetrated for the first time in its mission the heart of Earth's auroral acceleration region (AAR) in December 2009 and January 2010. During this time a special AAR campaign was carried out by the various Cluster instrument teams with special support from ESA and NASA facilities. We present some of the first multi-spacecraft observations of the waves, particles and fields made during that campaign. The Cluster spacecraft configuration during these AAR passages was such that it allowed us to explore the differences in the signatures of waves, particles, and fields on the various spacecraft in ways not possible with single spacecraft. For example, one spacecraft was more poleward than the other three (C2), one was at higher altitude (C1), and one of them (0) followed another (C4) through the AAR on approximately the same track but delayed by three minutes. Their separations were generally on the order of a few thousand km or less and occasionally two of them were lying along the same magnetic field line. We will show some of the first analyses of the data obtained during the AAR campaign, where upward and downward current regions, and the waves specifically associated with those regions, as well as the auroral cavities, were observed similarly and differently on the various spacecraft, helping us to explore the spatial, as well as the temporal, aspects of processes occurring in the AAR

Magneto‐structural studies of paramagnetic metal cages

A central concern within the field of molecular magnetism has been the elucidation of magneto-structural correlations. This thesis describes a variety of systems and endeavours to study the relationship between structure and magnetic properties in these systems. The first body of work (chapters 2 and 3) studies CrIII dimers, with the metal centres displaying a dialkoxo bridging moiety and latterly an additional carboxylate bridge to direct the synthesis of ferromagnetic analogues. The second section of work (chapters 4‐6) moves forward to the study of larger, heterometallic 3d‐3d compounds, through the synthesis of a large family of Anderson type MIII 2MII 5 wheels and a subsequent family of (VIVO)2MII 5 wheels. Chapter 2 describes a series of di‐alkoxo bridged Cr(III) dimers, synthesised using the pyridine alcohol ligands 2‐pyridinemethanol (hmpH) and 2‐pyridineethanol (hepH) as well as 2‐picolinic acid (picH). The structures fall into four general categories and are of formula: [Cr2(OMe)2(pic)4], [Cr2(hmp)2(pic)2X2] (where X = Cl, Br), [Cr2(L)2Cl4(A)2] (where L = hmp, A = H2O; L = hmp, A = pyridine; L = hmp, A = 4‐picoline; L = hep, A = H2O), and [Cr(hmp)(hmpH)Cl2. Magnetic studies show relatively weak antiferromagnetic exchange interactions between the Cr(III) centres and DFT calculations are used to develop magneto‐structural correlations, showing that the magnitude and sign of the J value is strongly dependent upon the orientation of the dihedral angle formed between the bridging Cr2O2 plane and the O–R vector of the bridging group, and the Cr–O–Cr–O dihedral angle. Chapter 3 builds on the work from the previous chapter with discussion of a large family of chromium(III) dimers, synthesised using a combination of carboxylate and diethanolamine type ligands. The compounds have the general formula [Cr2(R1‐deaH)2(O2CR2)Cl2]Cl where R1 = Me and R2 = H, Me, CMe3, Ph, 3,5‐(Cl)2Ph, (Me)5Ph, R1 = Et and R2 = H, Ph. The compound [Cr2(Me‐deaH)2Cl4] was also synthesised in order to study the effect of removing/adding the carboxylate bridge to the observed magnetic behaviour. Magnetic studies reveal ferromagnetic exchange interactions between the Cr(III) centres in the carboxylate bridged family with coupling constants in the range +0.37 < J < +8.02 cm‐1. Removal of the carboxylate to produce the dialkoxide‐bridged compound results in antiferromagnetic exchange between the Cr(III) ions. DFT calculations to further develop the magneto-structural correlations reveal the ferromagnetic exchange is the result of an orbital counter-complementarity effect occurring upon introduction of the bridging carboxylate. Chapter 4 reports a family of heterometallic Anderson‐type ‘wheels’ of general formula [MIII 2MII 5(hmp)12](ClO4)4 (where MIII = Cr or Al and MII = Ni or Zn giving [Cr2Ni5], [Cr2Zn5], [Al2Ni5] and [Al2Zn5]; hmpH = 2‐pyridinemethanol) synthesised solvothermally. The metallic skeleton describes a centred hexagon with the MIII sites disordered around the outer wheel. The structural disorder is characterised via single crystal X‐ray crystallography, 1‐3D 1H and 13C solution‐state NMR spectroscopy of the diamagnetic analogue, and solid‐state 27Al MAS NMR spectroscopy of the Al containing analogues. Alongside ESI mass spectrometry, these techniques show that structure is retained in solution, and that the disorder is present in both the solution and solid‐state. Solid‐state dc susceptibility and magnetisation measurements on [Cr2Zn5] and [Al2Ni5] reveal the Cr‐Cr and Ni‐Ni exchange interactions to be JCr‐Cr = ‐1 cm‐1 and JNi‐Ni,r = ‐5 cm‐1, JNi‐Ni,c = 10 cm‐1. Fixing these values allows us to extract JCr‐Ni,r = ‐1.2 cm‐1, JCr‐Ni,c = 2.6 cm‐1, the exchange between adjacent Ni and Cr ions on the ring is antiferromagnetic and between Cr ions on the ring and the central Ni ion is ferromagnetic. Chapter 5 focusses on planar molecules, espanding the family of heterometallic Anderson‐type ‘wheels’ discussed in chapter 4 to include MIII = Cr, Al and MII = Co, Fe, Mn, Cu, affording five new species of formulae [Cr2Co5(hmp)12](ClO4)4, [Cr2Fe5(hmp)12](ClO4)4, [Cr2Mn5(hmp)12](ClO4)4, [Cr2Cu5(hmp)12](ClO4)2(NO3)2 and [Al2Co5(hmp)12](ClO4)4. As per previous family members, the two MIII sites are disordered around the outer wheel, with the exception of [Cr2Cu5] where the the CuII sites are localised. A structurally related, but enlarged planar disc possessing a [MIII 6MII] hexagon capped on each edge by a CuII ion is also reported, which is formed only when MIII = Al and MII = Cu. In [AlIII 6CuII 7(OH)12(hmp)12](ClO4)6(NO3)2 the Anderson moiety contains a central, (symmetry‐imposed) octahedral CuII ion surrounded by a wheel of AlIII ions. Solid‐state dc susceptibility and magnetisation measurements reveal the presence of competing exchange interactions in the Anderson wheels family, and weak antiferromagnetic exchange between the CuII ions in [Al6Cu7]. Chapter 6 describes two heterometallic wheels of formula [(VIVO)2MII 5(hmp)10Cl2](ClO4)2∙2MeOH (where MII = Ni or Co) displaying the same Anderson‐type structure as seen in chapters 4 and 5, however the use of the vanadyl moiety has the effect of removing the disorder, with the two vanadyl ions sitting on opposing sides of the ring. The magnetic properties of both show competing antiferroand ferromagnetic interactions