The paper presents the first SIMS SHRIMP U-Pb data for zircon from an olivine horizon within the Nyud intrusion of the ore-bearing layered Monchegorsk pluton (Monchepluton) in the Kola Region, ...Russia. A 100–150 m-thick olivine horizon occurs nearly horizontally between the melanocratic and mesocratic norite of the Nyud intrusion, which disturbs its normal cumulus stratigraphic sequence. In addition, the pyroxene-plagioclase hornfelses are present at the upper contact with the olivine horizon. Twenty-three zircon grains were extracted from the large-volume olivine plagio-orthopyroxenite sample and clustered into two populations. The first population of magmatic zircon (n = 8) has a concordant and weighted average 207Pb/206Pb age of 2484.3 ± 5.6 Ma, which characterizes the formation time of the olivine horizon rocks. This serves as evidence of the olivine horizon that forms as a result of additional magma injection, which does not contradict the geological data. The 207Pb/206Pb age of single-grain zircon is 2414 ± 25 Ma, which indicates the time of postmagmatic transformations. The second population of zircon (n = 16) has a concordant and weighted average U-Pb age of 2700.6 ± 4.6 Ma, which indicates zircon absorption by olivine horizon magma probably from the rocks of the Archean greenstone belt.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Biocompatibility and high loading capacity of mesoporous CaCO3 vaterite crystals give an option to utilize the polycrystals for a wide range of (bio)applications. Formation and transformations of ...calcium carbonate polymorphs have been studied for decades, aimed at both basic and applied research interests. Here, composite multilayer-coated calcium carbonate polycrystals containing Fe3O4 magnetite nanoparticles and model protein lysozyme are fabricated. The structure of the composite polycrystals and vaterite → calcite recrystallization kinetics are studied. The recrystallization results in release of both loaded protein and Fe3O4 nanoparticles (magnetic manipulation is thus lost). Fe3O4 nanoparticles enhance the recrystallization that can be induced by reduction of the local pH with citric acid and reduction of the polycrystal crystallinity. Oppositely, the layer-by-layer assembled poly(allylamine hydrochloride)/poly(sodium styrenesulfonate) polyelectrolyte coating significantly inhibits the vaterite → calcite recrystallization (from hours to days) most likely due to suppression of the ion exchange giving an option to easily tune the release kinetics for a wide time scale, for example, for prolonged release. Moreover, the recrystallization of the coated crystals results in formulation of multilayer capsules keeping the feature of external manipulation. This study can help to design multifunctional microstructures with tailor-made characteristics for loading and controlled release as well as for external manipulation.
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IJS, KILJ, NUK, PNG, UL, UM
Abstract
Multiband optical photometry data of blazar S5 0716+714 obtained from 2002 to 2019 reveal stable color index change with flux variability. We analyzed this trend under variability caused by ...the Doppler factor change in the presence of a curved photon energy spectrum. A break in the energy spectrum of emitting electrons, caused by radiative losses, or log-parabolic electron energy distribution, or the synchrotron self-absorption acting in a compact jet part forms such the photon spectrum. We explained the observed color index change with variability by geometric effects only under the assumption that the radiating region is the synchrotron self-absorbed core and the bright optically thin jet. In this framework, we estimated the magnetic field strength in the optically thick part of the radiating region. These values correspond to other independent estimates of the magnetic field near the black hole, further supporting our assumption.
In this paper we present a new solution of the star-triangle relation having positive Boltzmann weights. The solution defines an exactly solvable two-dimensional Ising-type (edge interaction) model ...of statistical mechanics where the local “spin variables” can take arbitrary integer values, i.e., the number of possible spin states at each site of the lattice is infinite. There is also an equivalent “dual” formulation of the model, where the spins take continuous real values on the circle. From algebraic point of view this model is closely related to the 6-vertex model. It is connected with the construction of an intertwiner for two infinite-dimensional representations of the quantum affine algebra Uq(slˆ(2)) without the highest and lowest weights. The partition function of the model in the large lattice limit is calculated by the inversion relation method. Amazingly, it coincides with the partition function of the off-critical 8-vertex free-fermion model.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
We obtain a new solution of the star–triangle relation with positive
Boltzmann weights, which contains as special cases all continuous and
discrete spin solutions of this relation, that were ...previously known. This
new master solution defines an exactly solvable two lattice model of statistical
mechanics, which involves continuous spin variables, living on a
circle, and contains two temperature-like parameters. If one of the these
parameters approaches a root of unity (corresponds to zero temperature),
the spin variables freezes into discrete positions, equidistantly spaced on
the circle. An absolute orientation of these positions on the circle slowly
changes between lattice sites by overall rotations. Allowed configurations
of these rotations are described by classical discrete integrable equations,
closely related to the famous Q_4-equations by Adler, Bobenko and Suris.
Fluctuations between degenerate ground states in the vicinity of zero
temperature are described by a rather general integrable lattice model
with discrete spin variables. In some simple special cases, the latter
reduces to the Kashiwara–Miwa and chiral Potts models.
We show that the celebrated six-vertex model of statistical mechanics (along with its multistate generalizations) can be reformulated as an Ising-type model with only a two-spin interaction. Such a ...reformulation unravels remarkable factorization properties for row to row transfer matrices, allowing one to uniformly derive all functional relations for their eigenvalues and present the coordinate Bethe ansatz for the eigenvectors for all higher spin generalizations of the six-vertex model. The possibility of the Ising-type formulation of these models raises questions about the precedence of the traditional quantum group description of the vertex models. Indeed, the role of a primary integrability condition is now played by the star-triangle relation, which is not entirely natural in the standard quantum group setting, but implies the vertex-type Yang-Baxter equation and commutativity of transfer matrices as simple corollaries. As a mathematical identity the emerging star-triangle relation is equivalent to the Pfaff-Saalschütz-Jackson summation formula, originally discovered by J. F. Pfaff in 1797. Plausibly, all vertex models associated with quantized affine Lie algebras and superalgebras can be reformulated as Ising-type models with only two-spin interactions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Optimizing the cargo flows through the nodes of a digital transport corridor is a crucial problem; solving it allows to introduce modern management methods in logistics. This study examines the ...optimization of the technology of a distribution center as the base node of a third-party logistics network operator. Our objective consisted in theoretically substantiating the application of mathematical formalisms to describing the passage of stochastic goods flows of a complex structure through a node of a logistics network. To solve the problem, we constructed a mathematical model intended as a decision-making block in the Warehouse Management System software. This paper presents the results of calculations carried out using a computer according to the proposed algorithm. Preliminary results allow to conclude that there is a significant resource for reducing construction and maintenance costs of the distribution center. Quantitatively, the savings will range from 10% to 40%, depending on the terms of delivery of goods and the degree of market uncertainty. An example of a practical calculation using the developed mathematical model is given. The calculations were performed for Huawei, a key global provider of ICT infrastructure and smart terminals. The algorithms were designed to account for uncertainty, which allows to use the results for risk management applications. In practice, this theoretical concept can serve as a basis for digital logistics platforms, increasing the speed of delivery of goods and cargo and the profitability of logistics as a result. The solution to this problem will allow to consider the nodes of logistics networks as smart independent divisions with an information interface for interaction built into a digital logistics platform. The role of these nodes is to make the best decisions in handling cargo flows. As the next stage of research, we plan to develop algorithms for coordinating the information flows reflecting transport activities and forming the material flows entering and leaving the distribution centers.
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CEKLJ, GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The main problems that arise for novice researchers – undergraduates and graduate students of architecture and art – when conducting historical research in the professional area of architecture, ...urban planning, and design are identified and analyzed. In this area, the implementation (design) and the study (historical research) of professional activity are fundamentally different: they have different goals, means, methods and foundations (scientific base). Three groups of problems have been identified. The first group is caused by a misunderstanding of the above fundamental difference. The second group logically follows from the first and manifests itself in a misunderstanding of a number of fundamental requirements for dissertation research (novelty and reliability of research results). The third group is due to the lack of practical experience in conducting historical research, which leads to unlawful use of methods and categories of thinking borrowed from design activities.
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