Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki最新文献_第7页

The Left-Invariant Contact Metric Structure on the Sol Manifold Sol流形上的左不变接触度量结构

IF 0.3

Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki Pub Date : 2020-01-01 DOI: 10.26907/2541-7746.2020.1.77-90

V. I. Pan’zhenskii, B. A. Rastrepina

{"title":"The Left-Invariant Contact Metric Structure on the Sol Manifold","authors":"V. I. Pan’zhenskii, B. A. Rastrepina","doi":"10.26907/2541-7746.2020.1.77-90","DOIUrl":"https://doi.org/10.26907/2541-7746.2020.1.77-90","url":null,"abstract":"Among the known eight-dimensional Thurston geometries, there is a geometry of the Sol manifold – a Lie group consisting of real special matrices. For a left-invariant Riemannian metric on the Sol manifold, the left shift group is a maximal simple transitive group of isometry. In this paper, we found all left-invariant diﬀerential 1-forms and proved that on the oriented Sol manifold there is only one left-invariant diﬀerential 1-form, such that this form and the left-invariant Riemannian metric together deﬁne the contact metric structure on the Sol manifold. We identiﬁed all left-invariant contact metric connections and distinguished ﬂat connections among them. A completely non-holonomic contact distribution along with the restriction of a Riemannian metric to this distribution deﬁne the contact metric structure on the Sol manifold, and an orthogonal projection of the Levi-Chivita connection is a truncated connection. We obtained geodesic parameter equations of the truncated connection, which are the sub-geodesic equations, using a non-holonomic ﬁeld of frames adapted to the contact metric structure. We revealed that these geodesics are a part of the geodesics of the ﬂat contact metric connection.","PeriodicalId":41863,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki","volume":"51 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86017513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

On the Chromatic Number of Graphs with Some Restriction of Vertex Degrees 具有顶点度限制的图的色数

IF 0.3

Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki Pub Date : 2020-01-01 DOI: 10.26907/2541-7746.2020.4.387-395

S. Selezneva

引用次数: 0

Estimation of the Heterogeneity of the Reservoir Fluid Inflow to the Cross-Sectional Contour of a Vertical Well 直井剖面上储层流体流入非均质性的估计

IF 0.3

Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki Pub Date : 2020-01-01 DOI: 10.26907/2541-7746.2020.2.180-192

K. Potashev, R. Akhunov

{"title":"Estimation of the Heterogeneity of the Reservoir Fluid Inflow to the Cross-Sectional Contour of a Vertical Well","authors":"K. Potashev, R. Akhunov","doi":"10.26907/2541-7746.2020.2.180-192","DOIUrl":"https://doi.org/10.26907/2541-7746.2020.2.180-192","url":null,"abstract":"Estimation of the heterogeneity of the reservoir fluid inflow to the cross-sectional contour of a vertical well. Russian) Abstract The reasons for the heterogeneity of the reservoir fluid inflow to the cross-sectional contour of a vertical well can be: a) asymmetry of the external pressure field relative to the well axis as a result of the interference of the surrounding wells; b) heterogeneity of the permeability field near the well, which is a consequence of either the heterogeneity of the absolute permeability field of the reservoir or the mobility function of the multiphase mixture of formation fluids. To simulate filtration in a reservoir over a relatively long time interval, the main interest is constant or long-term factors associated with well spacing and the distribution of absolute permeability. In the work, solutions of two model problems were constructed, which allow a quantitative evaluation of the influence of both factors on the degree of inhomogeneity of the inflow to the well and indicate the conditions under which this effect becomes significant. The obtained estimates are intended primarily for computational schemes of streamline and streamtube methods, which require a high degree of solution detailing near wells.","PeriodicalId":41863,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki","volume":"39 2 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82831873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Miscalculation of Two-Phase Turbulent Jet Parameters While Using One-Liquid Mathematical Model 用单液体数学模型计算两相湍流射流参数的错误

IF 0.3

Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki Pub Date : 2020-01-01 DOI: 10.26907/2541-7746.2020.4.411-425

Yu. V. Zuev

引用次数: 0

The Molecular Dynamics of Silica Acids in Aqueous Solution: Qualitative and Quantitative Characteristics of Oligomers 水溶液中二氧化硅酸的分子动力学:低聚物的定性和定量特征

IF 0.3

Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki Pub Date : 2020-01-01 DOI: 10.26907/2541-7746.2020.1.5-26

E. Izotova, M. Rudakova, N. Akberova

{"title":"The Molecular Dynamics of Silica Acids in Aqueous Solution: Qualitative and Quantitative Characteristics of Oligomers","authors":"E. Izotova, M. Rudakova, N. Akberova","doi":"10.26907/2541-7746.2020.1.5-26","DOIUrl":"https://doi.org/10.26907/2541-7746.2020.1.5-26","url":null,"abstract":"In this work, we studied the diversity of silicic acid oligomers with Si n =(3 − 8) obtained during molecular dynamics in a reaction Feston–Garofalini force field that describes the process of oligomerization of silicic acids in an aqueous solution at the atomic level. Two systems with different concentrations of silicic acids, including 576 and 729 monomers Si(OH) 4 , were studied. According to the calculation results, the highest frequency isomers were represented by linear and branched forms. Throughout the simulation, a high level of dimers was constantly observed. The silicic acids oligomers size increased over time up to 27 Si atoms. The distribution of oligomers by the frequency of permeability for Si n =(3 − 5) was almost completely comparable with the NMR 29Si and quantum-chemical calculations. A previously undescribed new low-frequency isomer presented in both studied systems was identified among the pentamers. For oligomers with Si n =(6 − 8) , a wide variety of spatial isomers were observed; some of them have been partially or completely detected experimentally. Analysis of the Si average coordination number during MD simulation showed that 98% of Si atoms have a degree of coordination IV.","PeriodicalId":41863,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki","volume":"12 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81207811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Binomial Probability Estimates with Restrictions on Their d-Risks 具有d风险限制的二项概率估计

IF 0.3

Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki Pub Date : 2020-01-01 DOI: 10.26907/2541-7746.2020.1.91-97

R. Salimov, I. Kareev

引用次数: 0

Selenophysics and Models of the Lunar Three-Layered Mantle 月球三层地幔的月面物理和模型

IF 0.3

Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki Pub Date : 2019-01-01 DOI: 10.26907/2541-7746.2019.1.24-38

E. Kronrod, Y. Nefedyev, V. Kronrod, O. Kuskov, A. Andreev

引用次数: 4

Square-Induced Interpolation Problems for Entire Functions 整函数的平方插值问题

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Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki Pub Date : 2019-01-01 DOI: 10.26907/2541-7746.2019.1.119-126

F. N. Garif'yanov, E. Strezhneva

引用次数: 0

The Influence of the End Shape of the Liquid Jet on Its Impact onto a Dry Wall 液体射流端部形状对其撞击干壁面的影响

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Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki Pub Date : 2019-01-01 DOI: 10.26907/2541-7746.2019.1.39-52

A. Aganin, T. Guseva

引用次数: 1

Simplicial Fixed Point Algorithm with 2d Integer Labels 二维整数标号的简单不动点算法

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Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki Pub Date : 2019-01-01 DOI: 10.26907/2541-7746.2019.1.127-144

M. N. Matveev

引用次数: 0