{"?xml":{"@version":"1.0"},"edm:RDF":{"@xmlns:dc":"http://purl.org/dc/elements/1.1/","@xmlns:edm":"http://www.europeana.eu/schemas/edm/","@xmlns:wgs84_pos":"http://www.w3.org/2003/01/geo/wgs84_pos","@xmlns:foaf":"http://xmlns.com/foaf/0.1/","@xmlns:rdaGr2":"http://rdvocab.info/ElementsGr2","@xmlns:oai":"http://www.openarchives.org/OAI/2.0/","@xmlns:owl":"http://www.w3.org/2002/07/owl#","@xmlns:rdf":"http://www.w3.org/1999/02/22-rdf-syntax-ns#","@xmlns:ore":"http://www.openarchives.org/ore/terms/","@xmlns:skos":"http://www.w3.org/2004/02/skos/core#","@xmlns:dcterms":"http://purl.org/dc/terms/","edm:WebResource":[{"@rdf:about":"http://www.dlib.si/stream/URN:NBN:SI:DOC-UFJ9WYM6/e997a793-b0ed-4cce-8fe2-0b5ae57fc0b3/HTML","dcterms:extent":"21 KB"},{"@rdf:about":"http://www.dlib.si/stream/URN:NBN:SI:DOC-UFJ9WYM6/19429900-561e-4251-9998-2dd1509392e0/PDF","dcterms:extent":"113 KB"},{"@rdf:about":"http://www.dlib.si/stream/URN:NBN:SI:DOC-UFJ9WYM6/9e4338c1-9463-402f-94f0-70b78215beaf/TEXT","dcterms:extent":"19 KB"}],"edm:TimeSpan":{"@rdf:about":"2000-2024","edm:begin":{"@xml:lang":"en","#text":"2000"},"edm:end":{"@xml:lang":"en","#text":"2024"}},"edm:ProvidedCHO":{"@rdf:about":"URN:NBN:SI:DOC-UFJ9WYM6","dcterms:isPartOf":[{"@rdf:resource":"https://www.dlib.si/details/urn:nbn:si:spr-ihg6vo21"},{"@xml:lang":"sl","#text":"Materiali in tehnologije"}],"dcterms:issued":"2011","dc:creator":["Drbohlav, Jan","Kašpárková, Věra","Kucharczyk, Pavel","Poljanšek, Ida","Sedlarik, Vladimír","Šalaková, Alexandra"],"dc:format":[{"@xml:lang":"sl","#text":"številka:3"},{"@xml:lang":"sl","#text":"letnik:45"},{"@xml:lang":"sl","#text":"str. 265-268"}],"dc:identifier":["ISSN:1580-2949","COBISSID:860586","URN:URN:NBN:SI:doc-UFJ9WYM6"],"dc:language":"en","dc:publisher":{"@xml:lang":"sl","#text":"Inštitut za kovinske materiale in tehnologije"},"dc:subject":[{"@xml:lang":"sl","#text":"mlečna kislina"},{"@xml:lang":"sl","#text":"nečistoče"},{"@xml:lang":"sl","#text":"polikondenzacija"},{"@xml:lang":"sl","#text":"proteini"},{"@rdf:resource":"http://www.wikidata.org/entity/Q161249"}],"dcterms:temporal":{"@rdf:resource":"2000-2024"},"dc:title":{"@xml:lang":"sl","#text":"Biodegradable polymers from renewable resources| Biorazgradljivi polimeri iz obnovljivih virov| effect of proteinic impurityon polycondensation products of 2-hydroxypropanoic acid| vpliv proteinskih nečistoč na produkte polikondenzacije 2-hidroksipropanojske kisline|"},"dc:description":[{"@xml:lang":"sl","#text":"The goal of the presented work is to describe the proteinic impurity (as possible residual component from biotechnological lactic acid production from whey) in the reaction mixture with 2-hydroxypropanoic acid (lactic acid) for its direct polycondensation into poly(lactic acid). The impurity presence study was carried out in the range from mass fractions 0 % up to 2 %. For an evaluation of the impurity effect on the values of molecular weight, melting and glass transition temperatures the measurements of intrinsic viscosity, gel permeation chromatography and differential scanning calorimetry were used. Results show slight reduction of molecular weight and increase in polydispersity with rising amount of the impurity. The thermal properties investigation shows noticeable reduction of melting temperature and moderate decrease in glass transition temperature. The results reveal considerable role of lactose on formation of structural irregularities in lactic acid polycondensates"},{"@xml:lang":"sl","#text":"V prispevku je predstavljena študija vpliva proteinskih nečistot, ki so v reakcijski mešanici, na polikondenzacijo 2-hidroksipropanojske kisline (mlečne kisline) do polimlečne kisline. Koncentracijsko območje nečistot (komponente, ki ostanejo pri biotehnološki pridelavi mlečne kisline iz sirotke) je bilo od 0 % do 2 % glede na monomer. Z meritvami lastne viskoznosti in z gelsko prepustnostno kromatografijo ter diferenčno dinamično kalorimetrijo smo preučevali vpliv nečistot na povprečno molsko maso, na temperaturo tališča in na temperaturo steklastega prehoda nastalih polimerov. Z naraščajočo koncentracijo nečistot vrednost povprečnih molskih mas pada, narašča pa indeks polidisperznosti polimernih molekul. Rezultati raziskave termičnih lastnosti kažejo znižanje temperature tališča in tudi zmerno znižanje temperature steklastega prehoda z naraščajočo koncentracijo nečistot. Iz rezultatov študije je razvidna pomembna vloga laktoze na tvorbo strukturnih nepravilnosti pri polikondenzaciji mlečne kisline"}],"edm:type":"TEXT","dc:type":[{"@xml:lang":"sl","#text":"znanstveno časopisje"},{"@xml:lang":"en","#text":"journals"},{"@rdf:resource":"http://www.wikidata.org/entity/Q361785"}]},"ore:Aggregation":{"@rdf:about":"http://www.dlib.si/?URN=URN:NBN:SI:DOC-UFJ9WYM6","edm:aggregatedCHO":{"@rdf:resource":"URN:NBN:SI:DOC-UFJ9WYM6"},"edm:isShownBy":{"@rdf:resource":"http://www.dlib.si/stream/URN:NBN:SI:DOC-UFJ9WYM6/19429900-561e-4251-9998-2dd1509392e0/PDF"},"edm:rights":{"@rdf:resource":"http://rightsstatements.org/vocab/InC/1.0/"},"edm:provider":"Slovenian National E-content Aggregator","edm:intermediateProvider":{"@xml:lang":"en","#text":"National and University Library of Slovenia"},"edm:dataProvider":{"@xml:lang":"sl","#text":"Inštitut za kovinske materiale in tehnologije"},"edm:object":{"@rdf:resource":"http://www.dlib.si/streamdb/URN:NBN:SI:DOC-UFJ9WYM6/maxi/edm"},"edm:isShownAt":{"@rdf:resource":"http://www.dlib.si/details/URN:NBN:SI:DOC-UFJ9WYM6"}}}}