Entity

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. Source


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. Source


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. Source


Pielichowska K.,AGH University of Science and Technology | Pielichowski K.,Cracow University of Technology
Progress in Materials Science | Year: 2014

Phase change materials (PCMs) used for the storage of thermal energy as sensible and latent heat are an important class of modern materials which substantially contribute to the efficient use and conservation of waste heat and solar energy. The storage of latent heat provides a greater density of energy storage with a smaller temperature difference between storing and releasing heat than the sensible heat storage method. Many different groups of materials have been investigated during the technical evolution of PCMs, including inorganic systems (salt and salt hydrates), organic compounds such as paraffins or fatty acids and polymeric materials, e.g. poly(ethylene glycol). Historically, the relationships between the structure and the energy storage properties of a material have been studied to provide an understanding of the heat accumulation/emission mechanism governing the material's imparted energy storage characteristics. This paper reviews the present state of the art of PCMs for thermal energy storage applications and provides an insight into recent efforts to develop new PCMs with enhanced performance and safety. Specific attention is given to the improvement of thermal conductivity, encapsulation methods and shape stabilization procedures. In addition, the flame retarding properties and performance are discussed. The wide range of PCM applications in the construction, electronic, biomedical, textile and automotive industries is presented and future research directions are indicated. © 2014 Elsevier B.V. All rights reserved. Source


Kwapien J.,Polish Academy of Sciences | Drozdz S.,Polish Academy of Sciences | Drozdz S.,Cracow University of Technology
Physics Reports | Year: 2012

Typically, complex systems are natural or social systems which consist of a large number of nonlinearly interacting elements. These systems are open, they interchange information or mass with environment and constantly modify their internal structure and patterns of activity in the process of self-organization. As a result, they are flexible and easily adapt to variable external conditions. However, the most striking property of such systems is the existence of emergent phenomena which cannot be simply derived or predicted solely from the knowledge of the systems' structure and the interactions among their individual elements. This property points to the holistic approaches which require giving parallel descriptions of the same system on different levels of its organization. There is strong evidence-consolidated also in the present review-that different, even apparently disparate complex systems can have astonishingly similar characteristics both in their structure and in their behaviour. One can thus expect the existence of some common, universal laws that govern their properties. Physics methodology proves helpful in addressing many of the related issues. In this review, we advocate some of the computational methods which in our opinion are especially fruitful in extracting information on selected-but at the same time most representative-complex systems like human brain, financial markets and natural language, from the time series representing the observables associated with these systems. The properties we focus on comprise the collective effects and their coexistence with noise, long-range interactions, the interplay between determinism and flexibility in evolution, scale invariance, criticality, multifractality and hierarchical structure. The methods described either originate from "hard" physics-like the random matrix theory-and then were transmitted to other fields of science via the field of complex systems research, or they originated elsewhere but turned out to be very useful also in physics - like, for example, fractal geometry. Further methods discussed borrow from the formalism of complex networks, from the theory of critical phenomena and from nonextensive statistical mechanics. Each of these methods is helpful in analyses of specific aspects of complexity and all of them are mutually complementary. © 2012 Elsevier B.V. Source

Discover hidden collaborations