Innovation approaches in seismic microzonation tailing dump designing

Рассматриваются современные подходы оценки влияния локальных условий на сейсмическую опасность территорий. На примере хвостохранилищ горно-обогатительных комбинатов показано, что привлечение цифровых моделей среды и расчетных методов является важным элементом при прогнозировании влияния строения грунтовой толщи, ее физических свойств и антропогенного рельефа на усиление сейсмических колебаний грунта.Розглядаються сучасні підходи оцінки впливу локальних умов на сейсмічну небезпеку території. На прикладі хвостосховищ гірничо-збагачувальних комбінатів показано, що залучення цифрових моделей середи і розрахункових методів є важливим елементом при прогнозуванні впливу побудови грунтової товщі, її фізичних властивостей та антропогенного рельєфу на посилення сейсмічних коливань грунту.Current approaches of assess the impact of local conditions on the seismic hazard areas are considered. On the example of ore-dressing and processing enterprises tailings is shown that engaging of digital environment models and calculation methods is an important element in predicting the effect of the structure of a ground layer, its physical properties and anthropogenic relief to seismic ground motion amplification

Thermoluminescence of Magnesium Oxide Ceramics Obtained by the Method of Electron Beam Synthesis

The luminescent properties of MgO ceramics synthesized by the electron beam method were investigated. The luminescence centers were identified in the samples. The TL curves and dose characteristics of TL peaks excited by a pulsed electron beam (130 keV, 1.5–60 kGy) were analyzed

Self-assembled monolayers of alendronate on Ti6Al4V alloy surfaces enhance osteogenesis in mesenchymal stem cells

Phosphonates have emerged as an alternative for functionalization of titanium surfaces by the formation of homogeneous self-assembled monolayers (SAMs) via Ti-O-P linkages. This study presents results from an investigation of the modification of Ti6Al4V alloy by chemisorption of osseoinductive alendronate using a simple, effective and clean methodology. The modified surfaces showed a tailored topography and surface chemistry as determined by SEM microscopy and RAMAN spectroscopy. X-ray photoelectron spectroscopy revealed that an effective mode of bonding is created between the metal oxide surface and the phosphate residue of alendronate, leading to formation of homogenous drug distribution along the surface. In-vitro studies showed that alendronate SAMs induce differentiation of hMSC to a bone cell phenotype and promote bone formation on modified surfaces. Here we show that this novel method for the preparation of functional coatings on titanium-based medical devices provides osseoinductive bioactive molecules to promote enhanced integration at the site of implantation

Influence of Molecular Structure on the Rate of Intersystem Crossing in Flexible Biradicals

Laser flash photolysis (LFP), low-field chemically induced dynamic nuclear polarization (CIDNP), and time-resolved electron paramagnetic resonance (TREPR) techniques have been used for the comparative study of magnetic field and spin effects in acyl−ketyl and bis(ketyl)biradicals formed during the photolysis of 2-hydroxy-2,12-dimethylcyclododecanone (1-OH) and 2,12-dihydroxy-2,12-dimethylcyclododecanone (2-OH), respectively. The short biradical lifetime, the small magnetic field effect (MFE) on a biradical lifetime, and the low intensity of spin-correlated radical pair (SCRP) polarization observed during the photolysis of 1-OH indicate that the main channel of intersystem crossing in acyl−ketyl biradical is spin−orbit coupling (SOC). For bis(ketyl) biradicals observed during the photolysis of 2-OH, SOC is of minor importance, and both MFE and SCRP polarization are much larger. It is shown that the presence of significant SOC in biradicals can result in an increase of the CIDNP intensity at low magnetic fields. Calculations of biradical evolution, based on the numerical solution of the stochastic Liouville equation (SLE), were carried out by taking into account (1) the molecular dynamics of the polymethylene chain linking the radical centers, (2) the distance-dependent exchange interaction, (3) the chemical reactions of the biradical, (4) the spin relaxation processes, and (5) state-to-state transitions caused by hyperfine interaction and SOC. A common set of parameters was found which allows quantitative description of the field dependence of the biradical lifetime, the CIDNP field dependence, and the TREPR spectra and kinetics

Chemically Triggered C-ON Bond Homolysis of Alkoxyamines. Quaternization of the Alkyl Fragment

WOS:000298828500092International audienceThe C-ON bond homolysis in alkoxyamine 2a can be chemically triggered by the protonation of the 4-pyridylalkyl fragment. The resulting 15-fold increase In k(d) (Chem. Commun. 2011, 47, 4291-4293) was investigated experimentally and theoretically by quaternization of the pyridyl moiety using methylating (MeOTs), acylating (AcCl), and benzylating (PhCH2Br) agents as well as by oxidation of the pyridyl moiety into N-oxide and by the formation of a dative bond with BH3 as a Lewis acid