Mineral-petrochemical wallrock alteration of rocks in Bericul gold-ore deposit (Kuznetsk Alatau)

The distribution of mineral associations in near-veined zonal propylite-beresite metasomatic columns of mesothermal Bericul gold-ore deposit was analyzed. However, the polymineral composition in the inner (axial and adjacent with it rear) zones is inconsistent to the existing metasomatic column theoretical model. According to Korzhinskii metasomatic zoning theory, implied monomineral (quartz) and binary-mineral (quartz, sericite) compositions are characteristic of axial and rear zones, respectively. In common with above-mentioned facts, the zoning formation of differential component mobility is influenced by two additional factors: counter diffusion of components from fractured fluids into pores and diffusion mechanism of mass transfer it's from pores fluids into fractured of rock-fluid systems

Statistical Multifragmentation Model within the Extended Morphological Thermodynamics Approach

On the basis of morphological thermodynamics we develop an exactly solvable version of statistical mutifragmentation model for the nuclear liquid-gas phase transition. It is shown that the hard-core repulsion between spherical nuclei generates only the bulk (volume), surface and curvature parts of the free energy of the nucleus, while the Gaussian curvature one does not appear in the derivation. The phase diagram of nuclear liquid-gas phase transition is studied for a truncated version of the developed model.Comment: Talk given at XIX Igor Sikorsky Kyiv Polytechnic Institute Conference "Theoretical and Practical Problems of Physics, Mathematics and Informatics" , May 13-14, 2021, Kyiv, Ukraine (4 pages, 2 figures

Wave-vector dependent intensity variations of the Kondo peak in photoemission from CePd3_3

Strong angle-dependent intensity variations of the Fermi-level feature are observed in 4d - 4f resonant photoemission spectra of CePd$_3$(111), that reveal the periodicity of the lattice and largest intensity close to the Gamma points of the surface Brillouin zone. In the framework of a simplified periodic Anderson model the phenomena may quantitatively be described by a wave-vector dependence of the electron hopping matrix elements caused by Fermi-level crossings of non-4f-derived energy bands

Statistical multifragmentation model within the extended morphological thermodynamic approach

On the basis of morphological thermodynamics we develop an exactly solvable version of statistical mutifragmentation model for the nuclear liquid-gas phase transition. It is shown that the hard-core repulsion between spherical nuclei generates only the bulk (volume), surface and curvature parts of the free energy of the nucleus, while the Gaussian curvature one does not appear in the derivation. The phase diagram of nuclear liquid-gas phase transition is studied for a truncated version of the developed model

CeFePO: f-d hybridization and quenching of superconductivity

Being homologue to the new, Fe-based type of high-temperature superconductors, CeFePO exhibits magnetism, Kondo and heavy-fermion phenomena. We experimentally studied the electronic structure of CeFePO by means of angle-resolved photoemission spectroscopy. In particular, contributions of the Ce 4f-derived states and their hybridization to the Fe 3d bands were explored using both symmetry selection rules for excitation and their photoionization cross-section variations as a function of photon energy. It was experimentally found - and later on confirmed by LDA as well as DMFT calculations - that the Ce 4f states hybridize to the Fe 3d states of d_{3z^2-r^2} symmetry near the Fermi level that discloses their participation in the occurring electron-correlation phenomena and provides insight into mechanism of superconductivity in oxopnictides.Comment: 5 pages, 3 figure

Порушення функціонування сполученої системи “відновлені тіоли – оксид азоту” при гострому порушенні мозкового кровообігу та можливі шляхи їх корекції

Experimental acute ischemic stroke was modeled by bilateral occlusion of the common carotid arteries in rats. Antioxidant system in the brain tissue was evaluated by the activity of key enzymes of thiol and disulfide indicators nitrosative stress. Simulation of acute ischemic accompanied by violation of the thiol-disulfide balance and increased nitrotyrosine levels, indicating that the development of oxidative and nitrosative stress in brain tissue. It is established that the use of thiol-containing antioxidants – Thiotriazoline and Angiolin set the highest possible ratio between the levels of reduced and oxidized thiol groups and glutathione, which indicates that the active mobilization of thioldisulfide system in the neutralization products of free-radical oxidation. Identified effects of the drugs used due to the presence in their structure of the thiol group, which contributes to the normalization of the glutathione system in conditions of oxidative stress.Экспериментальное острое нарушение мозгового кровообращения моделировали путем двусторонней окклюзии общих сонных артерий у крыс. Состояние антиоксидантной системы в мозговой ткани оценивали по активности ключевых ферментов тиол-дисульфидной системы и показателям нитрозативного стресса. Моделирование острого ишемического поражения головного мозга сопровождалось нарушением тиол-дисульфидного равновесия, повышением активности NO-синтазы и уровня нитротирозина, что свидетельствует о развитии оксидативного и нитрозативного стресса. Использование модуляторов тиол-дисульфидной системы – тиотриазолина и ангиолина позволяет установить наиболее оптимальное соотношение между уровнями восстановленной и окисленной тиольных групп и глутатиона. Это указывает на активное участие тиол-дисульфидной системы в нейтрализации продуктов свободнорадикального окисления. Выявленные эффекты препаратов объясняются наличием в их структуре тиольной группы, которая играет роль скавенджера NO и способствует ограничению цитотоксического действия нитрозативного стресса.Експериментальне гостре порушення мозкового кровообігу моделювали шляхом двосторонньої оклюзії загальних сонних артерій у щурів. Стан антиоксидантної системи в мозковій тканині оцінювали за активністю ключових ферментів тіол-дисульфідної системи та показниками нітрозативного стресу. Моделювання гострого ішемічного ураження головного мозку супроводжувалося порушенням тіолдисульфідної рівноваги, підвищенням активності NO-синтази і рівня нітротирозину, що свідчить про розвиток оксидативного та нітрозативного стресу. Використання модуляторів тіол-дисульфідної системи – тіотриазоліну й ангіоліну дозволяє встановити найбільш оптимальне співвідношення між рівнями відновленої та окисненої тіольних груп і глутатіону. Це вказує на активну участь тіол-дисульфідної системи в нейтралізації продуктів вільнорадикального окиснення. Виявлені ефекти препаратів можна пояснити наявністю в їх структурі тіольної групи, яка відіграє роль скавенджеру NO та сприяє обмеженню цитотоксичної дії нітрозативного стресу.ітрозативного стресу

Dispersion of a single 4f4f impurity state in photoemission spectra of Yb/W(110)

Angle-resolved photoemission spectra of a monolayer of Yb on W(110) reveal energy splittings and dispersion of the Yb 4f states that are obviously due to their hybridization with W-derived valence bands. These effects occur at well defined points of the surface Brillouin zone although a smearing over reciprocal space is expected from the structural incoherence of the Yb and W lattices. We conclude therefore that dispersion is not related to the periodic arrangement of the $4f$ states but reflects the k-dependent interaction of a single Yb 4f impurity with W bands.Comment: 7 pages, 4 figure

Theoretical study about L-arginine complexes formation with thiotriazolin

Brain vascular diseases are one of the leading causes of morbidity, mortality and disability of population in the industrialized countries of the world. An important element of this problem’s solution is the creation of new highly effective and safe drugs, which would lead to mortality reduction, to increase in life expectancy and quality of life. Therefore it is interesting to create a new combined drug based on L-arginine and thiotriazolin. Purpose of the study: to consider the possible structure and energy characteristics of complexes formed by L-arginine, 3-methyl-1,2,4-triazolyl-5-thioacetate (MTTA) and morpholine. Calculation method. The initial approximation to the complex geometry was obtained using molecular docking with the help of AutoDock Vina program. The obtained ternary complexes were pre-optimized by semi-empirical PM7 method with modeling the impact of the environment by COSMO method. The calculations were carried out using MOPAC2012 program. Then they were optimized by B97-D3/SVP + COSMO (Water) dispersion-corrected DFT-D with geometrical spreading correction on insufficiency of gCP basis set. A more accurate calculation of the solvation energy was conducted by SMD. The calculations by density functional method were carried out using the ORCA 3.0.3 software. Energy complex formation in solution was calculated as the difference of the Gibbs free energy of the solvated complex and its individual components. Results. Quantum chemical calculations show, that thiotriazolin and L-arginine are able to form ternary complexes, where molecules are linked by multiple hydrogen bonds. The calculation data suggest, that studied complexes are thermodynamically unstable in solution. The energies of them are positive, but rather low despite charge gain of a number of intermolecular hydrogen bonds. Finding. Based on the results of the conducted quantum-chemical study of a three components system (MTTA, morpholine, and L-arginine) it is possible to show the possibility to form ternary complexes with low stability in infinite dilute solutions. It should be noted that two negative charges are always localized in formed complexes on the deprotonated carboxyl groups. The positive charges are located either on the guanidine moiety and the a-amino group of L-arginine, or on the guanidine moiety of L-arginine and protonated molecule of morpholine. It can be expected that the strengthening of intermolecular interactions in the real solutions may result in increased stability of the complexes