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Exceptional and semi simple Lie groups hierarchies and the maximum number of elementary particles beyond the standard model of high energy physics
Leila Marek-Crnjac, 2008, original scientific article

Abstract: In this work and following some major developments in our understanding of the connection between the exceptional Lie symmetry groups hierarchy and physics, we present finite and infinite dimensional Lie groups and their connections to the orthogonal and unitary groups. The dimension of the Lie group is included in the derivation of the number of elementary particle-likes uper states 576 and 672. Connections to the dimensions of Lie groups and the 72 and 84 elementary particles recently considered by the Author are discussed.
Keywords: Lie groups, elementary particles, algebra
Published: 31.05.2012; Views: 1428; Downloads: 63
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Lie groups hierarchy in connection with the derivation of the inverse electromagnetic fine structure constant from the number of particle-like states 548, 576 and 672
Leila Marek-Crnjac, 2008, original scientific article

Abstract: In this work we present different mathematical derivations of the inverse electromagnetic fine structure constant from the dimension of the compactified Klein modular curve, the dimension of the exceptional Lie group E8 E8 and from the number of states 548, 576 and 672. We show the close connection of the number of particle-like states 548, 576 and 672 with the dimensions of Lie groups, specially with E71/2 and other exceptional Lie groups.
Keywords: Lie groups, Klein-modular curve, particles
Published: 31.05.2012; Views: 1491; Downloads: 42
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Analysis of the oxidation of cellulose fibres by titration and XPS
Lidija Fras Zemljič, Leena Sisko Johansson, Peer Stenius, Janne Laine, Karin Stana-Kleinschek, Volker Ribitsch, 2005, original scientific article

Abstract: The purpose of this study was to evaluate the effect of selective oxidation on the surface properties of cotton cellulose fibres. Four different methods to evaluate the accessibility, nature and content of ionisable acidic groups (charge) in the fibres were applied: potentiometric and conductometric titrations, polyelectrolyte adsorption and X-ray photoelectron spectroscopy (XPS). The results from this combination of methods show that two processes take place when the oxidation method is applied: elimination of low molecular mass non-cellulosic compounds and formation of new acidic groups in the cellulose chains. Which of these processes is predominating depends on oxidation time, but the first one is initially more important. Polyelectrolyte adsorption and XPS show that the surface concentration of acidic groups is considerably lower than the bulk concentration, i.e. during oxidation the content of carboxyl groups in the surface region decreases, while it increases in amorphous regions. The decrease is due to the dissolution of low molecular weight compounds; the increase is due to the formation of new acidic groups. The use of titration methods in combination with XPS appears to be a very useful tool for identification of the formation and distribution of ionic groups in cotton fibres and their surfaces.
Keywords: textile fibres, cotton fibres, cellulose fibres, oxidation, X-ray photoelectron spectroscopy, XPS, acid groups in fibres
Published: 01.06.2012; Views: 1351; Downloads: 71
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Characterization of amino groups for cotton fibers coated with chitosan
Lidija Fras Zemljič, Simona Strnad, Olivera Šauperl, Karin Stana-Kleinschek, 2009, original scientific article

Abstract: The adsorption of chitosan onto cellulose cotton fibers introduces antimicrobial properties, mainly created by the amount and location of amino groups. Therefore, it is important to be able to analyze both parameters, especially in a heterogeneous system, namely cotton fibers coated with chitosan. In this research, three different analytical techniques were applied to determine amino groups of cotton fibers coated with chitosan. The number of positively charged groups was determined indirectly by the spectrophotometric method using Acid Orange 7 dye, and the use of polyelectrolyte titration. In addition, the chemical surface composition regarding non-modified, as well as modified cotton fibers (coated with chitosan), was investigated using X-ray Photoelectron Spectroscopy (XPS). The results from a combination of these methods show that chitosan treatment introduces more than 14 mmol/kg of accessible amino groups onto the cotton fibers. The results were in good agreement with the results of XPS. The use of spectrophotometric and titration methods in combination with XPS appears to be a very useful tool for identifying the formation of amino groups in modified cotton fibers and their surfaces.
Keywords: cotton, cellulose, oxidation, chitosan, amino-groups, titration, XPS
Published: 01.06.2012; Views: 1059; Downloads: 104
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Topochemical modification of cotton fibres with carboxymethyl cellulose
Lidija Fras Zemljič, Peer Stenius, Janne Laine, Karin Stana-Kleinschek, 2008, original scientific article

Abstract: The research reported in this paper demonstrates that the capacity of cotton fibres to adsorb cationic surfactants as well as the rate of the adsorption process can be increased by adsorbing carboxymethyl cellulose (CMC) onto the fibre surfaces; in addition, the adsorption can be restricted to the fibre surface. CMC was deposited by means of adsorption from an aqueous solution. The adsorption of N-cetylpyridinium chloride (CPC) from an aqueous solution onto the CMC-modified fibres was measured using UVspectrometric determination of the surfactant concentration in the solution. Adsorption onto the cotton fibres was studied in a weakly basic environment (pH 8.5) where cotton fibres are negatively charged and the CPC ion is positively charged. Modification of the fibres by adsorption of CMC introduces new carboxyl groups onto the fibre surfaces, thereby increasing the adsorption capacity of the fibres for CPC. The initial rate of adsorption of CPC increased proportionally with the amountof charge; however, this rate slowed down at high degrees of coverage onfibres with a high charge. The adsorption of cationic surfactant to the anionic surface groups was stoichiometric, with no indication of multilayer oradmicelle formation. It was evident that the acidic group content of the fibres was the primary factor determining cationic surfactant adsorption to these fibres.
Keywords: textile fibres, cotton fibres, modification, carboxymethyl cellulose, acid groups, charge increase, conductiometric titration, phenol-sulphuric acid test, practical applications
Published: 01.06.2012; Views: 1091; Downloads: 71
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Multicriteria evaluation of high-speed rail, transrapid Maglev and Air passenger transport in Europe
Milan Janić, 2003, original scientific article

Abstract: This article deals with a multicriteria evaluation of High-Speed Rail, Transrapid Maglev and Air Passenger Transport in Europe. Operational, socio-economic and environmental performance indicators of the specific high-speed transport systems are adopted as the evaluation criteria. By using the entropy method, weights are assigned to particular criteria in order to indicate their relative importance in decision-making. The TOPSIS method is applied to carry out the multicriteria evaluation and selection of the preferable alternative (high-speed system) under given circumstances.
Keywords: high-speed transport systems, Europe, multicriteria analysis, entropy method, interest groups
Published: 05.06.2012; Views: 1477; Downloads: 74
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Exceptional Lie groups hierarchy, orthogonal and unitary groups in connection with symmetries of E-infinity space-time
Leila Marek-Crnjac, 2008, original scientific article

Abstract: Prikazane so različne izpeljave 548 izometrij E-neskončno simetrijske grupe. Najdena je povezava med dimenzijami izjemnih Liejevih grup, ortogonalnimi, unitarnimi grupami in 548. V delu je podanih nekaj argumentov za izpeljavo inverzne elektromagnetne konstante iz 1152 bozonov in enakega števila fermionov, sledeč kvantizaciji svetlobnega stožca GS delovanja super Maxwellove teorije.
Keywords: izjemne Liejeve grupe, Kleinov modularni prostor, Killingov vektor, Riemannov tenzor, exceptional Lie groups, Klein-modular space, Killing vector, Riemann tensor
Published: 10.07.2015; Views: 357; Downloads: 64
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Group decision making
Vladislav Rajkovič, 2011, original scientific article

Abstract: The paper discusses group decision making as a way of managing decision knowledge. Described are pros and cons of group decision making. Special emphasis is given to the leveraging of different interests and possibilities of formulating a joint decision. Available methods and techniques together with a properly organized group work can make a substantial contribution.
Keywords: decision making, groups, conflict of interest, leveraging interests, hierarchical modelling
Published: 10.07.2015; Views: 642; Downloads: 49
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Usefulness of the patient information leaflet (PIL) and information on medicines from professionals
Tonka Poplas-Susič, Zalika Klemenc-Ketiš, Janko Kersnik, 2014, original scientific article

Abstract: Background: The Patient information leaflet (PIL) is an important source of information for every patient. Little is known about whether patients read the PIL and whether it contains useful information. Other sources of drug-related information are professionals (a family practitioner, a pharmacist and a nurse). Informing patients on drugs improves their compliance. The aim of the study was to identify the usefulness of PIL from the perspective of the patient, to assess professionals as a source of drug-related information and to suggest changes that can improve informing and therefore patients' compliances. Methods: Four focus group interviews were conducted across different primary health care centres in the North East of Slovenia. Focus groups were composed of randomly selected patients (in total 20) who were willing to express their views on PILs, on other drug information sources and on possible improvements. A qualitative analysis of the data was based of the transcription of the audiotapes. Results: Patients read the PILs selectively. They were most interested in side effects, contraindications and the purpose of the prescribed drug. Participants reported that the language in PILs is too scientific. In the case they do not understand PILs or they recognise some of the side effects, a majority of participants decide to contact a family physician first, and less frequently a pharmacist or a nurse. A family physician is considered to be the most trustworthy source of information and patients think that pharmacists could play a more active role in patients% education. Conclusion: Current PILs offer enough partial information to patients but need some improvements in terms of better legibility and access to the most crucial information. PIL does not enable a comprehensive information with respect to patient%s health status. Most reliable source of information is considered to be a family practitioner. Pharmacists could play a more active role in the education of patients.
Keywords: PIL, focus groups, medicines, family practitioner
Published: 10.05.2017; Views: 550; Downloads: 26
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Modification of PET-polymer surface by nitrogen plasma
Rok Zaplotnik, Metod Kolar, Aleš Doliška, Karin Stana-Kleinschek, 2011, original scientific article

Abstract: Low pressure weakly nitrogen plasma was applied for incorporation of nitrogen-containing functional groups onto poly(ethylene terephthalate) - PET polymer. Nitrogen plasma was created in an electrode-less radiofrequency discharge at the nominal power of 200 W and the frequency of 27.12 MHz. Nitrogen molecules entered the discharge region were highly excited, partially dissociated and weakly ionized. Transformation into the state of plasma allowed for creation of chemically reactive particles with a high potential energy while the kinetic energy remained close to the value typical for room temperature. The chemical reactivity allowed for rapid functionalization with nitrogen-rich functional groups. The appearance of these groups was monitored by X-ray photoelectron spectroscopy - XPS. The polymer surface was quickly saturated with nitrogen indicating that the modification was limited to an extremely thin surface film.
Keywords: poly(ethylene terephthalate), nitrogen plasma, surface modification, functional groups, X-ray photoelectron spectroscopy
Published: 17.03.2017; Views: 342; Downloads: 62
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