Time filter

Source Type

Cracow, Poland

Tadeusz Kościuszko University of Technology is a public university located in central Kraków, Poland, established in 1946 and, as an institution of higher learning granted full autonomy in 1954.Over 37,000 students graduated from the Polytechnic to this day with degrees. Doctorate degrees were granted to 1200 persons and Habilitated degrees - to additional 300. The number of students admitted each year reaches 4500. Wikipedia.

DFT calculations have proven clearly the polar nature of gem-dinitroethene cycloaddition to (Z)-C,Ndiphenylnitrone. The formation of the azolidine ring on both analysed [2+3] cycloaddition pathways occurs in the gas phase according to the one-step mechanism. When toluene is added as the reaction medium, the kinetic pathway preference does not change. However, the mechanism for the formation of the 2,3-diphenyl-4,4-dinitroisoxazolidine heterocyclic ring does change. In the first reaction stage, a zwitterionic intermediate forms, which is only later cyclized to the [2+3] cycloadduct. © 2012 Elsevier Ltd. All rights reserved.

Plebankiewicz E.,Cracow University of Technology
Automation in Construction | Year: 2012

Contractor prequalification makes it possible to admit for tendering only competent contractors. The paper presents a proposal for contractor prequalification schema involving two stages of prequalification: "on a standing list" and "per project". A model of prequalification employing the theory of fuzzy sets to evaluate the "per project" contractors is precisely described. A simple numerical example illustrates the model operation and a description of a program supporting the prequalification procedure follows. © 2011 Elsevier B.V. All rights reserved.

Sciezor T.,Cracow University of Technology
Monthly Notices of the Royal Astronomical Society | Year: 2013

In this paper, I present a new method that has been developed for determining the brightness of a cloudless night sky, on the basis of widely available amateur observations of comets. The tests show the correctness of the method, which makes it possible to determine the level of light pollution, defined as the brightness of the artificial sky glow, through the use of the archival observations of comets. The use of data bases of comet observations in Poland in the period 1994-2009 has led to a positive verification of the known model map of the brightness of the night sky. Also, it has been possible to find changes in the level of light pollution in this period, at the selected observation sites. © 2013 The Author Published by Oxford University Press on behalf of the Royal Astronomical Society.

Domagala L.,Cracow University of Technology
Journal of Civil Engineering and Management | Year: 2011

Structural lightweight aggregate concrete (SLWAC) is an alternative building material to normal-weight one, due to its ability to reach a relatively high compressive strength at still significantly lower density. Nevertheless, the application of lightweight aggregate instead of normal-weight one to concrete must result in deterioration of some characteristics of the composite. One of the methods of improving SLWAC properties is incorporation of fibers into concrete. This paper focuses on the influence of steel fibres on modification of properties of structural lightweight concrete with sintered fly ash aggregate. Two different concrete mixtures, producing various levels of matured composite density and compressive strength, were modified with three dosages of fibers: 30, 45 and 60 kg/m3. The applied amounts did not result in significant deterioration of the rheological parameters of concrete mixtures. Despite relatively low volume content of fibres, a considerable increase of flexural and tensile splitting strength was observed. Fibres also improved concrete shrinkage as well as post-peak deformability in uni-axial compression. The effect of steel addition on compressive strength proved to be dependent on specimen type. Nevertheless, it was not as crucial as in the case of the above characteristics. However, the modulus of elasticity of SLWAC was not affected by fibre addition. © 2011 Vilnius Gediminas Technical University (VGTU) Press Technika.

Jasinski R.,Cracow University of Technology
Journal of Fluorine Chemistry | Year: 2014

Based on DFT computation data, a molecular mechanism of the thermal decomposition of fluoronitroazoxy compounds was studied. The processes were confirmed to proceed through five-membered cyclic Cope transition complexes, even though a different mechanism was previously suggested. Furthermore, it was proved that decomposition kinetics may be somewhat controlled by changing medium polarity and the character of the substituent in the fluoronitroazoxy compound. © 2014 Elsevier B.V.

Discover hidden collaborations