Search results for "transition"

A first-order phase transition for pulsar surface

2012

In this paper, we explain the existence of a possible first-order phase transition that may occur over the external solid crust of a pulsar, by means of an interpretation of a particular formal model (drawn from Theoretical Astrophysics) whose thermodynamical phenomenology shows a possible first-order phase transition (according to Landau’s Phenomenological Theory).

Preparation, crystal structure at 298 and 90 K and phase transition in (C2H5NH3) 2[SbBr5] studied by the single crystal X-Ray diffraction method

2004

The reaction of antimony(III) oxide with ethylamine, in molar ratios from 1:1 to 1:10, in concentrated hydrobromic acid leads to the formation of one product – bis(ethylammonium) pentabromoantimonate(III). The structure of (C2H5NH3)2[SbBr5] was determined at 298 and 90 K, below and above the phase transition that occurs at about 158.5 K. The orthorhombic system was found in both phases, space groups Cmca and Pbca at 298 and 90 K, respectively. At both temperatures the structure consists of [SbBr6] 3− octahedra connected via cis bromine atoms forming one-dimensional zig-zag [{SbBr5}2−]n chains. The ethylammonium cations fill the space between polyanionic chains. The organic and inorganic sub…

The Grain Boundary Wetting Phenomena in the Ti‐Containing  High‐Entropy Alloys: A Review

2021

This review is written during the preparation of M‐era.Net full proposal  ʺGrain boundaries in multicomponent alloys without principal componentʺ (A.K., A.K., G.A.L.  and E.R., application No. 9345). The Institute of Solid State Physics, University of Latvia, as a cen‐ ter of excellence, has received funding from the European Union’s Horizon 2020 Framework Pro‐ gramme H2020‐WIDESPREAD‐01‐2016‐2017‐TeamingPhase2 under grant agreement no. 739508,  project CAMART2. 

Majorana parameters of the interacting boson model of nuclear structure and their implication for 0νββ decay

2021

Aluminum tri-isopropoxide as an alternative precursor for atomic layer deposition of aluminum oxide thin films

2019

Due to the safety challenges associated with the use of trimethylaluminum as a metal precursor for the deposition of alumina, different chemicals have been investigated over the years to replace it. The authors have investigated the use of aluminum tri-isopropoxide (TIPA) as an alternative alkoxide precursor for the safe and cost-effective deposition of alumina. In this work, TIPA is used as a stable Al source for atomic layer deposition (ALD) of Al2O3 when different oxidizing agents including water, oxygen plasma, water plasma, and ozone are employed. The authors have explored the deposition of Al2O3 using TIPA in ALD systems operating in vacuum and atmospheric pressure conditions. For the…

Toward Sustainable PLA-Based Multilayer Complexes with Improved Barrier Properties

2019

Poly(lactic acid) or PLA is currently considered as one of the most promising substitutes of conventional plastics, with low environmental impact, especially for food packaging applications. Nevertheless, some drawbacks, such as high permeability to oxygen, are still limiting its industrial applications. The objective of this study was to highly increase the oxygen barrier performance of PLA without compromising its sustainable nature and following the principles of circular economy perspective. Coproducts coming from mill industries, such as wheat gluten proteins (WG), were used to produce PLA-WG-PLA multilayer complexes with improved barrier performance. Different technologies of industri…

Mniejszość niemiecka w Polsce a proces transformacji systemowej - założenia i wstępne wyniki badań

2021

The article presents the assumptions and partial results of the research undertaken within the project “German minority in Poland in the face of transition and political transformation after 1989”, carried out by a research team from the Institute of Political Science and Administration (University of Opole) and commissioned by the German Minority Research Center. The project is an attempt of adopting a new perspective on the processes related to the political transformation which Poland underwent 30 years ago, with an aim of investigating the role that the German minority played in this transition. Authors of the paper focused on discussing the current state of research and outlining the s…

Transition metal complexes of tetradentate and bidentate Schiff bases as catalysts for ethylene polymerization: Effect of transition metal and cocata…

2009

This article compares catalytic performance of ethylene polymerization in similar polymerization conditions of transition metal complexes having two ligands [O,N] (phenoxy-imine) and having one tetradentate ligand [O,N,N,O] (salphen or salen). It is shown that the activity of both complex types as well as the product properties depend in the same way on the type of central metal in the complex and on the cocatalyst used. Although the type of ligand has some effect on the catalyst activity, yet it does not control the properties of the obtained products. The vanadium and zirconium complexes, irrespective of the cocatalyst used, yield linear polyethylene with high molecular weight (a few hund…

Low-temperature single crystal X-ray diffraction and high-pressure Raman studies on [(CH3)2NH2]2[SbCl5]

2007

The structure of bis(dimethylammonium) pentachloroantimonate(III), [(CH{sub 3}){sub 2}NH{sub 2}]{sub 2}[SbCl{sub 5}], BDP, was studied at 15 K and ambient pressure by single-crystal X-ray diffraction as well as at ambient temperature and high pressures up to 4.87(5) GPa by Raman spectroscopy. BDP crystallizes in the orthorhombic Pnma space group with a=8.4069(4), b=11.7973(7), c=14.8496(7) A, and Z=4; R{sub 1}=0.0381, wR{sub 2}=0.0764. The structure consists of distorted [SbCl{sub 6}]{sup 3-} octahedra forming zig-zag [{l_brace}SbCl{sub 5}{r_brace}{sub n}]{sup 2n-} chains that are cross-linked by dimethylammonium [(CH{sub 3}){sub 2}NH{sub 2}]{sup +} cations. The organic and inorganic substr…

An algorithm based on the PPC (Polynomial Parametric Curve) for designing horizontal highway alignments

2015

Criteria for geometric design of highway alignments have been studied in various researches so far, providing new methods, as alternative to traditional approaches. They can be useful for obtaining better solutions, characterized by high performances in terms of motion safety and comfort. In particular, continuous curvature alignments, based on polynomial functions, are highly consistent solutions with users' driving behaviour and vehicle trajectories. Moreover, alignment geometry optimization allows engineers to minimize dynamic effects on drivers with considerable advantages in terms of comfort and safety. This paper carries on the research of a previous study, in which a polynomial param…