369 research outputs found
Debye Limiting Law Violation in Clusters and Nanostructures
In this work fractal continuum model of condensed matter was used. Calculations of vibrational spectra
of molecular clusters were carried out. It was established that temperature changes of heat capacity
associated to intermolecular oscillations in clusters does not obey Debye limiting law.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3524
Посухостійкість гібридів яблуні з участю сорту Видубицька плакуча в умовах Лісостепу України
Objective – to determine the drought-resistance of hybrids of Vydubytska plakucha apple × Malus domestica Borkh cultivars in Forest-Steppe of Ukraine, waterlogging of tissues, water-retaining capacity, the general deficit of water in leaves and their turgorisation.
Material and methods. The drought tolerance of 15 hybrids of the apple of the Vydubytska plakucha × cultivers M. domestica from the gene-pool M.M. Gryshko National Botanical Garden of the NAS of Ukraine. Hyb ri dization was carried out to obtain decorative forms, apple trees with a sign of «weeping», inherited from the сultivar Vydubytska plakucha.
Results. The greatest amount of water was recorded in the leaves of hybrids of the V. p. × Khoroshovka (56.8 %), V. p. × 1–22 (54.3 %), the smallest – in the leaves of hybrids V. p. × Oranzheve (51.6 %), V. p. × Uralske nalyvne (50.0 %). Water deficiency in the leaves was 15–25 %, which does not lead to lethal damage to plants. A high percentage of the moisture content was characteristic of the V. p. × Khoroshovka, and the lowest was the hybrid of the V. p. × Renet Koksa Oranzhevyy.
Conclusion. The most drought-resistant are the hybrids of V. p. × Khoroshovka and V. p. × Luyiza, less stable – V. p. × Renet Koksa Oranzhevyy, V. p. × Uralske nalyvne, V. p. × Antor, the intermediate place is occupied by hybrid V. p. × Uelsi.Мета – визначити посухостійкість гібридів яблуні ‘Видубицька плакуча’ × сорти Malus domestica Borkh. у Лісостепу України, обводненість тканин, водоутримувальну здатність, загальний дефіцит води у листках та їх тургорисцентність.
Матеріал та методи. Оцінено посухостійкість 15 гібридів яблуні 'Видубицька плакуча' × сорти M. domestica з генофонду Національного ботанічного саду імені М.М. Гришка НАН України. Гібридизацію було проведено для одержання декоративних форм яблуні з ознакою “плакучість”, успадкованою від сорту ‘Видубицька плакуча’.
Результати. Найбільшу кількість води відзначено в листках гібридів В. п. × Хорошовка (56,8 %), В. п. × 1-22 (54,3 %), найменшу – в листках гібридів В. п. × Оранжеве (51,6 %), В. п. × Уральське наливне (50,0 %). Водний дефіцит у листках становив 15—25 %, що не призводить до летального пошкодження рослин. Найвищим відсотком утримання вологи характеризувалися В. п. × Хорошовка, а найнижчим – гібрид В. п. × Ренет Кокса Оранжевий.
Висновок. Найпосухостійкішими є гібриди В. п. × Хорошовка та В. п. × Луїза, менш стійкими – В. п. × Ренет Кокса Оранжевий, В. п. × Уральське наливне, В. п. × Антор, проміжне місце посідає гібрид В. п. × Уєлсі
Functional Coatings Based on Hydroxyapatite and Polymers Formed on Ti-6Al-4V Substrates
The paper describes perspective technology for deposition of inorganic-organic coatings used for biomedical
application. Synthetic hydroxyapatite was used as inorganic compound, due to the similarity of the
main component to bone tissue. As organic components we used chitosan and alginate – natural biopolymers,
which widely used for bioactive and biocompatible composites formation. Thermal substrate method
used for coatings deposition based on principle of decreasing solubility of hydroxyapatite with increasing of
substrate temperature and allow to deposit coatings at substrate temperatures below 100 °C. Porous composite
hydroxyapatite-chitosan and hydroxyapatite-alginate coatings were obtained on Ti-6Al-4V substrates.
Morphology, phase composition and adhesion to the substrate surface were investigated.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3529
Baxter Q-operator and Separation of Variables for the open SL(2,R) spin chain
We construct the Baxter Q-operator and the representation of the Separated
Variables (SoV) for the homogeneous open SL(2,R) spin chain. Applying the
diagrammatical approach, we calculate Sklyanin's integration measure in the
separated variables and obtain the solution to the spectral problem for the
model in terms of the eigenvalues of the Q-operator. We show that the
transition kernel to the SoV representation is factorized into the product of
certain operators each depending on a single separated variable. As a
consequence, it has a universal pyramid-like form that has been already
observed for various quantum integrable models such as periodic Toda chain,
closed SL(2,R) and SL(2,C) spin chains.Comment: 29 pages, 9 figures, Latex styl
Preclinical antitumor activity of the diindolylmethane formulation in xenograft mouse model of prostate cancer
Aim: Preclinical study of the specific anticancer pharmacological activity of the formulation containing active substance 3,3ʹ-diindolylmethane (DIM), cod liver oil, polysorbate 80 and α-tocopherol acetate (vitamin E), in vivo in a xenograft animal model of LNCaP. Materials and Methods: The DIM, cod liver oil, polysorbate 80 and α-tocopherol acetate (vitamin E) formulation was intragastrically administered to BALB/c-nude (nu/nu) mice during 33 days post inoculation at the dose of 133 mg/kg/day. Antitumor activity of the test drug was estimated by the rate of tumor growth inhibition (T/C% — treated versus control), dividing the tumor volumes from treatment groups with the control groups. Results: Statistically significant tumor xenograft regressions have been shown in group which received the DIM, cod liver oil, polysorbate 80 and α-tocopherol acetate (vitamin E) on the 37th day of observation post inoculation. The highest antitumor activity was achieved on the 39th day (T/C = 16,8%). Therapeutic effect lasts for 6 days after the end of therapy period. Conclusion: Our findings demonstrate inhibitory effect of the formulation on tumor development in the xenograft animal model due to the tumor growth rate reduction. Key Words: 3,3´-diindolylmethane, bioavailability, anticancer activity, xenograft model, LNCaP cell line, preclinical studies
Separation of variables for the quantum SL(2,R) spin chain
We construct representation of the Separated Variables (SoV) for the quantum
SL(2,R) Heisenberg closed spin chain and obtain the integral representation for
the eigenfunctions of the model. We calculate explicitly the Sklyanin measure
defining the scalar product in the SoV representation and demonstrate that the
language of Feynman diagrams is extremely useful in establishing various
properties of the model. The kernel of the unitary transformation to the SoV
representation is described by the same "pyramid diagram" as appeared before in
the SoV representation for the SL(2,C) spin magnet. We argue that this kernel
is given by the product of the Baxter Q-operators projected onto a special
reference state.Comment: 26 pages, Latex style, 9 figures. References corrected, minor
stylistic changes, version to be publishe
Electric field gradients in MgB synthesized at high pressure: Cd TDPAC study and ab initio calculation
We report the high-pressure synthesis of novel superconductor MgB and
some related compounds. The superconducting transition temperature of our
samples of MgB is equal to 36.6 K. The MgB lattice parameters
determined via X-ray diffraction are in excellent agreement with results of our
ab initio calculations. The time-differential perturbed angular correlation
(TDPAC) experiments demonstrate a small increase in quadrupole frequency of
Cd probe with decreasing temperature from 293 to 4.2 K. The electric
field gradient (EFG) at the B site calculated from first principles is in fair
agreement with EFG obtained from B NMR spectra of MgB reported in the
literature. It is also very close to EFG found in our Cd TDPAC
measurements, which suggests that the Cd probe substitutes for boron in
the MgB lattice.Comment: 10 pages, 3 figure
Optical Multicolor WBVR-Observations of the X-Ray Star V1341 Cyg = Cyg X-2 in 1986-1992
We present the results of observations of the low-mass X-ray binary
V1341 X--2. Our observations include a total of
2375 individual measurements in four bands on 478 nights in 1986-1992. We tied
the comparison and check stars used for the binary to the catalog using
their magnitudes. The uncertainty of this procedure was 3 in the
and bands and 8%-10% for the and bands. In quiescence, the
amplitude of the periodic component in the binary's brightness variations
is within ( in ); this is due
to the ellipsoidal shape of the optical component, which is distorted with
gravitational forces from the X-ray component. Some of the system's active
states (long flares) may be due to instabilities in the accretion disk, and
possibly to instabilities of gas flows and other accretion structures. The
binary possesses a low-luminosity accretion disk. The light curves reveal no
indications of an eclipse near the phases of the upper and lower conjunctions
in quiescence or in active states during the observed intervals. We conclude
that the optical star in the close binary V1341
X-2 is a red giant rather than a blue straggler. We studied the long-term
variability of the binary during the seven years covered by our observations.
The optical observations presented in this study are compared to X-ray data
from the Ginga observatory for the same time intervals.Comment: 35 pages, 8 figure
Structural Properties of Magnesium Oxide Thin Films Deposited by Spray Pyrolysis Technique
In this work, structural properties of magnesium oxide films have studied by X-ray diffraction methods. MgO obtained by spray pyrolysis technique at the different substrate temperatures on the glass substrates. The 0.2 M magnesium chloride hexahydrate aqueous solution was selected as a precursor in the solution. The influence of substrate temperature on the phase composition, texture quality, coherent scattering domain size and lattice constant of the material was investigated.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3710
Effect of electron irradiation on transparent conductive films ZnO:Al deposited at different sputtering power
Transparent conductive oxide thin films of Al-doped ZnO grown by rf magnetron sputtering were irradiated with high energy electrons with the energy 12.6 MeV and fluence 5·10¹⁴ e/cm². The films were produced using different sputtering powers. It has been shown that electron irradiation creates defects that lead to distortions of the crystal lattice, which results in reduced crystallinity of the films. Also, it leads to film heating that results in radiation annealing and relaxation of the lattice
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