Why is monoalkylation versus bis-alkylation of the Ni(II) complex of the Schiff base of (S)-N-(2-benzoylphenyl)-1-benzylpyrrolidine-2-carboxamide and glycine so selective? MP2 modelling and topological QTAIM analysis of chiral metallocomplex synthons of alpha-amino acids used for the preparation of radiopharmaceuticals for positron emission tomography

Chiral Ni(II) complexes are used for the preparation of carbon-11 or fluorine-18 enantiomerically pure alpha-amino acids for positron emission tomography (PET). They enable the selective monoalkylation of a glycine synthon with high stereoselectivity and the preparation of enantiomerically pure alpha-amino acids with quarternary alpha-carbon. Molecular modelling of non-, mono- and di-substituted complexes using quantum theory of atoms-in-molecule (QTAIM) topological analysis of electron density allowed us to formulate a new theory explaining the reasons for highly selective monomethylation of the complexes. In the non-substituted complex (GK), the alpha-carbon atom exhibits a higher atomic volume and a more positive charge in comparison with mono- and di-substituted complexes. This unusual behaviour is accompanied by increasing the bond critical point (BCP) ellipticity of the iminic bond in GK explained by the higher mechanical strain. Both phenomena indicate the increased reactivity and probably originate in more compact core of GK where shorter distances in the internal coordination sphere result in the higher strain of its bonds

{2-[(S)-({2-[(S)-1-Benzyl­pyrrolidine-2-carboxamido]phen­yl}(phen­yl)methyl­ene)amino]-4-hydroxy­butanoato-κ4 N,N′,N′′,O}nickel(II)

The central Ni atom of the title compound, [Ni(C29H29N3O4)], is coordinated by three N atoms [Ni—N = 1.955 (2), 1.844 (2) and 1.872 (2) Å] and by one O atom [Ni—O = 1.862 (2) Å] in a pseudo-square-planar geometry. The conformation of the hydroxy­butanoate side chain is controlled by a strong intra­molecular hydrogen bond (H⋯O = 1.84 Å)

Anomalous self-diffusion in the ferromagnetic Ising chain with Kawasaki dynamics

We investigate the motion of a tagged spin in a ferromagnetic Ising chain evolving under Kawasaki dynamics. At equilibrium, the displacement is Gaussian, with a variance growing as $A t^{1/2}$. The temperature dependence of the prefactor $A$ is derived exactly. At low temperature, where the static correlation length $\xi$ is large, the mean square displacement grows as $(t/\xi^2)^{2/3}$ in the coarsening regime, i.e., as a finite fraction of the mean square domain length. The case of totally asymmetric dynamics, where $(+)$ (resp. $(-)$) spins move only to the right (resp. to the left), is also considered. In the steady state, the displacement variance grows as $B t^{2/3}$. The temperature dependence of the prefactor $B$ is derived exactly, using the Kardar-Parisi-Zhang theory. At low temperature, the displacement variance grows as $t/\xi^2$ in the coarsening regime, again proportionally to the mean square domain length.Comment: 22 pages, 8 figures. A few minor changes and update

Инвестиционные модели ведения бизнеса в энергетическом секторе экономики

Investment by companies, which target growth of key labor productivity factors, labor attraction, modernization, and development, as well as reduction of production risks and higher investment attractiveness, is the main growth factor for emerging economies. However, the key drawbacks of the existing models of investment attractiveness assessment of state-sponsored projects are the absence of alternative financing from adjacent sources and the lack of the scenario approach when analyzing cash flows of a project. The authors’ scientific and practical research offers the choice of the best investment project model, ensuring a lower default risk, lesser expected losses for the state (in case of redeeming the loss, occurring in the case of breach of warranty), and a lower possibility of tax receipt shortfalls under the project. The measures imply the use of the scenario and probabilistic approach, ensuring consideration of all possible alternatives for an investment project of companies, engaged in the energy business, and, consequently, higher efficiency of budget spending.El factor principal en el crecimiento de las economías de tipo en desarrollo es la implementación de proyectos de inversión por parte de entidades comerciales centradas en el crecimiento de los principales factores de productividad, atracción de recursos laborales, modernización y desarrollo, reducción de los riesgos de producción y aumento del atractivo de la inversión. Al mismo tiempo, los principales inconvenientes de los modelos utilizados para evaluar los proyectos de inversión implementados con apoyo estatal son la falta de consideración de alternativas para el financiamiento de fuentes relacionadas, la no utilización del enfoque de escenario para analizar los flujos de efectivo del proyecto. Como parte de la investigación, se hizo una selección del modelo de proyecto de inversión más óptimo, que reduce el riesgo de una probabilidad de incumplimiento, reduce las pérdidas esperadas para el estado (en caso de compensación por daños incurridos en el caso de un evento de garantía), y reduce la probabilidad de ingresos fiscales por debajo de lo esperado para el presupuesto. . La implementación de estas medidas implica el uso del escenario y el enfoque probabilístico, que permite considerar todas las alternativas posibles para el proyecto de inversión para las empresas que realizan negocios en los sectores energéticos de la economía y, como consecuencia, la implementación de esta medida permite aumentar la eficiencia del uso de los fondos presupuestarios.Основным фактором роста экономики стран развивающего типа является реализация инвестиционных проектов хозяйствующими субъектами, ориентированными на рост основных факторов производительности, привлечении трудовых ресурсов, модернизации и развития, снижении производственных рисков и увеличении инвестиционной привлекательности. Вместе с тем основными недостатками используемых моделей оценки инвестиционных проектов, реализуемых за счет государственной поддержки, является отсутствие рассмотрение альтернатив финансирования из смежных источников, неиспользование сценарного подхода при анализе денежных потоков проекта. В рамках проведенного научного исследования предложен выбор наиболее оптимальной модели инвестиционного проекта, позволяющей снизить риск вероятности дефолта, уменьшить ожидаемые потери для государства (в случае возмещения ущерба, образовавшегося при наступлении гарантийного случая), снизить вероятность недополучения ожидаемых в рамках проекта налоговых поступлений в бюджет соответствующего уровня. Реализация данных мер подразумевает использование сценарного и вероятностного подхода, что позволяет рассматривать все возможные альтернативы для инвестиционного проекта для компаний, занимающихся ведением бизнеса в энергетических секторах экономики и как следствие реализация данной меры позволяет увеличить эффективность использования бюджетных средств

Concept and Essence of Social Supply Chain and Professional Self-Determination in education System

Abstract The author of this article reveals the content of the concepts of «identity», «professional identity», «social supply chain and professional identity» in education system. This topic has been recently studied as a system of value and supply of higher education. We made a conclusion about the need for the formation of social supply chain and professional identity of high school students, taking into account the spiritual and moral orientations, professional orientation, professional self-awareness of education system. The proposed social supply chain system can be effectively applied in the education system for various conditions

Critical phenomena and universal dynamics in one-dimensional driven diffusive systems with two species of particles

Recent work on stochastic interacting particle systems with two particle species (or single-species systems with kinematic constraints) has demonstrated the existence of spontaneous symmetry breaking, long-range order and phase coexistence in nonequilibrium steady states, even if translational invariance is not broken by defects or open boundaries. If both particle species are conserved, the temporal behaviour is largely unexplored, but first results of current work on the transition from the microscopic to the macroscopic scale yield exact coupled nonlinear hydrodynamic equations and indicate the emergence of novel types of shock waves which are collective excitations stabilized by the flow of microscopic fluctuations. We review the basic stationary and dynamic properties of these systems, highlighting the role of conservation laws and kinetic constraints for the hydrodynamic behaviour, the microscopic origin of domain wall (shock) stability and the coarsening dynamics of domains during phase separation.Comment: 72 pages, 6 figures, 201 references (topical review for J. Phys. A: Math. Gen.