Mössbauer study of slovak brown coal

In the present contribution, the results of Mössbauer analyses of three types of Slovak brown coal are presented. Electron microscopy and X-ray photoelectron spectroscopy were used as supplementary techniques. The dominant Fe bearing mineral was pyrite which contains from 78% up to 95% of the total amount of iron. The rest of iron is present in ferrous carbonate (siderite) and silicate (illite) phases. In one of the three samples a magnetically ordered component was identified.     

Reliable Numerical Computation in Civil Engineering

Civil engineering is a field – as are many other engineering sciences – where most of the methods used for solving optimization problems are based on experience and experiments, and models using local information, but drawn from global models. The present work outlines an interesting class of problems from this field, and initiates some possible ways to solve those problems utilizing the wide tool capabilities of interval arithmetic for error handling and interval branch-and-bound algorithms to solve the original or modified industrial models automating civil engineers' work. The investigations are in the first state but are promising both in a theoretical and in a practical sense.     

Multichip systems trade-off analysis tool

This article discusses the conceptual/specification phase of multichip system design. The automation of conceptual design practices will decrease design and manufacturing risks by allowing system designers to view the entire performance design space early in the design cycle prior to the initiation of traditional physical design activities.This article describes a software tool that performs interdisciplinary trade-off analysis and partitioning for multichip systems including multichip modules (MCMs) and traditional assembly approaches. The tool concurrently computes physical, electrical, thermal, reliability, testability, and cost performance metrics for multichip systems. This tool allows a large fraction of possible design, technology, material, test, and manufacturing approaches to be explored before decisions are made and resources committed.An example set of trade-off results are presented which examine the trade-off between peripheral I/O format die and area array I/O format die in an MCM, as a function of partitioning a fixed functionality into a variable number of die.Visiting researcher at MCC from Eastman Kodak Company.     

Synthesis of steroid precursors. Intramolecular Diels-Alder approach to the trans-hydrindenone system.

The intramolecular Diels-Alder reaction of the 1,3-propanediol-derived ketal of (6E)-2-methyl-1,6,8-nonatrien-3-one produces an approximately 3:1 ratio of trans- and cis-hydrindenones.     

CpPEt2As4—An Organic‐Substituted As4 Butterfly Compound

Cp^PEt₂As₄ (Cp^PEt=C₅(4‐EtC₆H₄)₅) ( 1 ) is synthesized by the reaction of Cp^PEt. radicals with yellow arsenic (As₄). In solution an equilibrium of the starting materials and the product is found. However, 1 can be isolated and stored in the solid state without decomposition. As₄ can be easily released from 1 under thermal or photochemical conditions. From powder samples of Cp^PEt₂As₄, yellow arsenic can be sublimed under rather mild conditions (T=125 °C). A similar behavior for the P₄‐releasing agent was determined for the related phosphorus compound Cp^BIG₂P₄ ( 2 ; Cp^BIG=C₅(4‐nBuC₆H₄)₅). DFT calculations show the importance of dispersion forces for the stability of the products.     

Ni-Catalyzed Regio- and Enantioselective Homoallylic Coupling: Synthesis of Chiral Branched 1,5-Dienes Featuring a Quaternary Stereogenic Center and Mechanistic Analysis

Asymmetric synthesis of small molecules comprising quaternary stereogenic carbon centers represents a challenging objective. Here regio- and enantioselective synthesis of chiral 1,5-dienes featuring quaternary stereocenters is reported via nickel-promoted by reductive homoallylic coupling. The developed methodology features an atypical preference for the formation of unusual branched regioisomers (rr >20 : 1) in a sterically challenging allylic substitution event and furnishes the products with enantiomeric ratios of up to 98 : 2 and with high chemo- and E-selectivity. A range of experimental evidences suggest that zinc plays a dual role to generate electrophilic and nucleophilic Ni(II)-allyl intermediates empowering a unique formal bimetallic cross-electrophile manifold in two separate kinetic regimes.     

Error analysis for full discretizations of quasilinear parabolic problems on evolving surfaces

Convergence results are shown for full discretizations of quasilinear parabolic partial differential equations on evolving surfaces. As a semidiscretization in space the evolving surface finite element method is considered, using a regularity result of a generalized Ritz map, optimal order error estimates for the spatial discretization is shown. Combining this with the stability results for Runge–Kutta and backward differentiation formulae time integrators, we obtain convergence results for the fully discrete problems. © 2016 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 32: 1200–1231, 2016