Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

This is a review of Collected Works of John Tate. Parts I, II, edited by Barry Mazur and Jean-Pierre Serre. American Mathematical Society, Providence, Rhode Island, 2016. For several decades it has been clear to the friends and colleagues of John Tate that a “Collected Works” was merited. The award of the Abel Prize to Tate in 2010 added impetus, and finally, in Tate’s ninety-second year we have these two magnificent volumes, edited by Barry Mazur and Jean-Pierre Serre. Beyond Tate’s published articles, they include five unpublished articles and a selection of his letters, most accompanied by Tate’s comments, and a collection of photographs of Tate. For an overview of Tate’s work, the editors refer the reader to [4]. Before discussing the volumes, I describe some of Tate’s work. 1. Hecke L-series and Tate’s thesis Like many budding number theorists, Tate’s favorite theorem when young was Gauss’s law of quadratic reciprocity. When he arrived at Princeton as a graduate student in 1946, he was fortunate to find there the person, Emil Artin, who had discovered the most general reciprocity law, so solving Hilbert’s ninth problem. By 1920, the German school of algebraic number theorists (Hilbert, Weber, . . .) together with its brilliant student Takagi had succeeded in classifying the abelian extensions of a number field K: to each group I of ideal classes in K, there is attached an extension L of K (the class field of I); the group I determines the arithmetic of the extension L/K, and the Galois group of L/K is isomorphic to I. Artin’s contribution was to prove (in 1927) that there is a natural isomorphism from I to the Galois group of L/K. When the base field contains an appropriate root of 1, Artin’s isomorphism gives a reciprocity law, and all possible reciprocity laws arise this way. In the 1930s, Chevalley reworked abelian class field theory. In particular, he replaced “ideals” with his “idèles” which greatly clarified the relation between the local and global aspects of the theory. For his thesis, Artin suggested that Tate do the same for Hecke L-series. When Hecke proved that the abelian L-functions of number fields (generalizations of Dirichlet’s L-functions) have an analytic continuation throughout the plane with a functional equation of the expected type, he saw that his methods applied even to a new kind of L-function, now named after him. Once Tate had developed his harmonic analysis of local fields and of the idèle group, he was able prove analytic continuation and functional equations for all the relevant L-series without Hecke’s complicated theta-formulas. Received by the editors September 5, 2016. 2010 Mathematics Subject Classification. Primary 01A75, 11-06, 14-06. c ©2017 American Mathematical Society

The collected works

The 2D–3D growth mode transition during the initial stages of growth of highly strained InGaAs on GaAs is used to obtain quantum‐sized dot structures. Transmission electron micrographs reveal that when the growth of In0.5Ga0.5As is interrupted exactly at the onset of this 2D–3D transition, dislocation‐free islands (dots) of the InGaAs result. Size distributions indicate that these dots are ∼300 A in diameter and remarkably uniform to within 10% of this average size. The areal dot densities can be varied between 109 and 1011 cm−2. The uniformity of the dot sizes is explained by a mechanism based on reduction in adatom attachment probabilities due to strain. We unambiguously demonstrate photoluminescence at ∼1.2 eV from these islands by comparing samples with and without dots. The luminescent intensities of the dots are greater than or equal to those of the underlying reference quantum wells.

Direct formation of quantum‐sized dots from uniform coherent islands of InGaAs on GaAs surfaces

Premises of creation of Internet portal designed to provide access to participants of educational and scientific process for the joint creation, consolidation, concentration and rapid spreading of educational and scientific information resources in its own depository are considered. CMS-based portal content management systems’ potentiality is investigated. Architecture for Internet portal of MES of Ukraine’s information resources is offered.

Створення порталу інформаційно-довідкових ресурсів міністерства освіти і науки україни

Crystallization is vital to many processes occurring in nature and in the chemical, pharmaceutical, and food industries. Notably, crystallization is an attractive isolation step for manufacturing because this single process combines both particle formation and purification. Almost all of the products based on fine chemicals, such as dyes, explosives, and photographic materials, require crystallization in their manufacture, and more than 90% of all pharmaceutical products contain bioactive drug substances and excipients in the crystalline solid state. Hence control over the crystallization process allows manufacturers to obtain products with desired and reproducible properties. We judge the quality of a crystalline product based on four main properties: size, purity, morphology, and crystal structure. The pharmaceutical industry in particular requires production of the desired crystal form (polymorph) to assure the bioavailability and stability of the drug substance. In solution crystallization, nucleation...

Nucleation of crystals from solution: classical and two-step models.

We review a plethora of relevant experimental results on internal homogeneous crystal nucleation in silicate glasses obtained in the last four decades, and their analyses in the framework of the classical nucleation theory (CNT). The basic assumptions and equations of CNT are outlined. Particular attention is devoted to the analysis of the properties of the critical nuclei, which, to a large extent, govern nucleation kinetics. The main methods employed to measure nucleation rates are described and the possible errors in the determination of the crystal number density (and, correspondingly, in nucleation rates) are discussed. The basic regularities of both time and temperature dependencies of nucleation rates are illustrated by numerous experimental data. Experimental evidence for a correlation between maximum nucleation rates and reduced glass transition temperatures is presented and theoretically justified. Special attention is given to serious problems that arise in the quantitative description of nucleation rates when using the CNT, for instance: the dramatic discrepancy between calculated and measured nucleation rates; the high value of the crystal nuclei/melt surface energy, σcm, if compared to the expected value estimated via Stefan’s rule; the increase of σcm with increasing temperature; and the discrepancies between the values of the surface energy and the time-lag for nucleation when independently estimated from nucleation and growth kinetics. The analysis of the above mentioned problems leads to the following conclusion: in contrast to Gibbs’ description of heterogeneous systems underlying CNT, the bulk thermodynamic properties of the critical nuclei generally differ from those of the corresponding macro-phase resulting simultaneously in significant differences of the surface properties as compared with the respective parameters of the planar interfaces. In particular, direct experimental evidence is presented for compositional changes of the crystal nuclei during formation of the critical nuclei and their growth from critical to macro-sizes. In addition, detailed examinations of crystal nucleation and growth kinetics show a decrease of both the thermodynamic driving force for nucleation and of the critical nuclei/liquid interfacial energy, as compared with the respective properties of the macro-phase. However, despite significant progress in understanding crystal nucleation in glasses in the past four decades, many problems still exist and this is likely to remain a highly interesting subject for both fundamental and applied research for a long time.

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Homogeneous crystal nucleation in silicate glasses: A 40 years perspective

Introduction.- States of Aggregation, Thermodynamic Phases, and the Vitreous State.- Non-Equilibrium Thermodynamics and the Kinetics of Glass Transition and Stabilization.- General Approaches to the Description of the Structure of Glasses.- Statistical Physics of Under-Cooled Melts and Glasses.- Nucleation in Glass-Forming Systems.- Catalyzed Crystallization of Glass-Forming Melts.- Theory of Crystal Growth and Dissolution in Under-cooled Melts.- Growth of Clusters. Ostwald's Rule of Stages.- Kinetics of Overall Crystallization.- Liquid Phase Separation in Glass-Forming Melts.- Rheology of Glass-Forming Melts.- Concluding Remarks.

The Vitreous State: Thermodynamics, Structure, Rheology, and Crystallization

Preface.List of Contributors.1 Introductory Remarks (Jurn W.P. Schmelzer).References.2 Solid-Liquid and Liquid-Vapor Phase Transitions: Similarities and Differences (Vladimir P. Skripov and Mars Z. Faizullin).2.1 Introduction.2.2 Behavior of the Internal Pressure.2.3 The Boundaries of Stability of a Liquid.2.4 The Surface Energy of the Interfacial Boundary.2.5 Viscosity of a Liquid along the Curves of Equilibrium with Crystalline and Vapor Phases.2.6 Conclusions.References.3 A New Method of Determination of the Coefficients of Emission in Nucleation Theory (Vitali V. Slezov, Jurn W. P. Schmelzer, and Alexander S. Abyzov).3.1 Introduction.3.2 Basic Kinetic Equations.3.3 Ratio of the Coefficients of Absorption and Emission of Particles.3.4 Generalization to Multicomponent Systems.3.5 Generalization to Arbitrary Boundary Conditions.3.6 Initial Conditions for the Cluster Size Distribution Function.3.7 Description of Cluster Ensemble Evolution Along a Given Trajectory.3.8 Conclusions.References.4 Nucleation and Crystallization Kinetics in Silicate Glasses: Theory and Experiment (Vladimir M. Fokin, Nikolay S. Yuritsyn, and Edgar D. Zanotto).4.1 Introduction.4.2 Basic Assumptions and Equations of Classical Nucleation Theory (CNT).4.3 Experimental Methods to Estimate Nucleation Rates.4.4 Interpretation of Experimental Results by Classical Nucleation Theory.4.5 Nucleation Rate Data and CNT: Some Serious Problems.4.6 Crystal Nucleation on Glass Surfaces.4.7 Concluding Remarks.References.5 Boiling-Up Kinetics of Solutions of Cryogenic Liquids (Vladimir G. Baidakov).5.1 Introduction.5.2 Nucleation Kinetics.5.3 Nucleation Thermodynamics.5.4 Experiment.5.5 Comparison between Theory and Experiment.5.6 Conclusions.References.6 Correlated Nucleation and Self-Organized Kinetics of Ferroelectric Domains (Vladimir Ya. Shur).6.1 Introduction.6.2 Domain Structure Evolution during Polarization Reversal.6.3 General Considerations.6.4 Materials and Experimental Conditions.6.5 Slow Classical Domain Growth.6.6 Growth of Isolated Domains.6.7 Loss of Domain Wall Shape Stability.6.8 Fast Domain Growth.6.9 Super fast Domain Growth.6.10 Domain Engineering.6.11 Conclusions.References.7 Nucleation and Growth Kinetics of Nanofilms (Sergey A. Kukushkin and Andrey V. Osipov).7.1 Introduction.7.2 Thermodynamics of Adsorbed Layers.7.3 Growth Modes of Nanofilms.7.4 Nucleation of Relaxed Nanoislands on a Substrate.7.5 Formation and Growth of Space-Separated Nanoislands.7.6 Kinetics of Nanofilm Condensation.7.7 Coarsening of Nanofilms.7.8 Nucleation and Growth of GaN Nanofilms.7.9 Nucleation of Coherent Nanoislands.7.10 Conclusions.References.8 Diamonds by Transport Reactions with Vitreous Carbon and from the Plasma Torch: New and Old Methods of Metastable Diamond Synthesis and Growth (Ivan Gutzow, Snejana Todorova, Lyubomir Kostadinov, Emil Stoyanov, Victoria Guencheva, Gunther Volksch, Helga Dunken, and Christian Russel).8.1 Introduction.8.2 Some History.8.3 Basic Theoretical and Empirical Considerations.8.4 Experimental Part.8.5 Conclusions.References.9 Nucleation in Micellization Processes (Alexander K. Shchekin, Fedor M. Kuni, Alexander P. Grinin, and Anatoly I. Rusanov).9.1 Introduction.9.2 General Aspects of Micellization: the Law of Mass Action and the Work of Aggregation.9.3 General Kinetic Equation of Molecular Aggregation: Irreversible Behavior in Micellar Solutions.9.4 Thermodynamic Characteristics of Micellization Kinetics in the Near-Critical and Micellar Regions of Aggregate Sizes.9.5 Kinetic Equation of Aggregation in the Near-Critical and Micellar Regions of Aggregate Sizes.9.6 Direct and Reverse Fluxes of Molecular Aggregates over the Activation Barrier of Micellization.9.7 Times of Establishment of Quasiequilibrium Concentrations.9.8 Time of Fast Relaxation in Surfactant Solutions.9.9 Time of Slow Relaxationin Surfactant Solutions.9.10 Time of Approach of the Final Micellization Stage.9.11 The Hierarchy of Micellization Times.9.12 Chemical Potential of a Surfactant Monomer in a Micelle and the Aggregation Work in the Droplet Model of Spherical Micelles.9.13 Critical Micelle Concentration and Thermodynamic Characteristics of Micellization.References.10 Nucleation in a Concentration Gradient (Andriy M. Gusak).10.1 Introduction.10.2 Phase Competition under Unlimited Nucleation.10.3 Thermodynamics of Nucleation in Concentration Gradients: Case of Full Metastable Solubility.10.4 Thermodynamics of Nucleation at the Interface: The Case of Limited Metastable Solubility.10.5 Kinetics of Nucleation in a Concentration Gradient.References.11 Is Gibbs' Thermodynamic Theory of Heterogeneous Systems Really Perfect? (Jurn W. P. Schmelzer, Grey Sh. Boltachev, and Vladimir G. Baidakov).11.1 Introduction.11.2 Gibbs' Classical Approach.11.3 A Generalization of Gibbs' Thermodynamic Theory.11.4 Applications: Condensation and Boiling in One-Component Fluids.11.5 Discussion.11.6 Appendix.References.12 Summary and Outlook (Jurn W.P. Schmelzer).References.Index.

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Nucleation theory and applications

The vitreous state

Glass-ceramics are noted for their unusual combination of properties and manifold commercialized products for consumer and specialized markets. Evolution of novel glass and ceramic processing routes, a plethora of new compositions, and unique exotic nano- and microstructures over the past 60 years led us to review the definition of glass-ceramics. Well-established and emerging processing methods, such as co-firing, additive manufacturing, and laser patterning are analyzed concerning the core requirements of processing glass-ceramics and the performance of the final products. In this communication, we propose a revised, updated definition of glass-ceramics, which reads “Glass-ceramics are inorganic, non-metallic materials prepared by controlled crystallization of glasses via different processing methods. They contain at least one type of functional crystalline phase and a residual glass. The volume fraction crystallized may vary from ppm to almost 100%”.

Jürn W. P. Schmelzer

Papers

Homogeneous crystal nucleation in silicate glasses: A 40 years perspective

The Vitreous State: Thermodynamics, Structure, Rheology, and Crystallization

Nucleation theory and applications

The vitreous state

Updated definition of glass-ceramics