KINETICS OF CELLULOSE DEGRADATION STUDIED USING SIZE EXCLUSION CHROMATOGRAPHYAneta Balažic Fabjan
, 2016, magistrsko delo
Opis: For more than five centuries, paper has been the predominant carrier of information and numerous medieval manuscripts bear witness of its durability. However, increasing demand for paper led to several changes in its production in the 19th century. High quality rag fibres were replaced by inferior wood-originating ones. Acid manufacturing technology was introduced which, due to its simplicity and low cost, continued to be used until the end of the 20th century. Inherently stable paper rapidly degrades in the presence of acids and its decay is further promoted by the poor storage conditions and environmental pollutants. As a result, the amount of degraded paper in libraries, archives and museums is reaching enormous proportions. In order to prolong the usable time of the vast quantities of original materials, paper collections may be deacidified and/or stored at lower temperatures. While preservation options are known, lack of the competent comparative studies leaves collection keepers hesitant of their use. The introductory part of the project is focused on development of analytical methodologies and model materials, representative of historical acid paper. As uniqueness and inherent value of cellulose-based cultural heritage limits the use of analytical methodologies to the non-destructive or micro-destructive ones. A new methodology for determination of the condition of paper was developed. The analytical technique-size exclusion chromatography for the first time allows us to reproducible determine the condition of paper which contains a significant amount of wood derived lignin. A few fibres suffice for the analysis, which renders the methodology suitable for characterisation of historical materials. The results of the research will represent the effect of deacidification processes with use of micro destructive analytical methodologies. As written word is all what we have for our legacy from generation to generation, evaluating preservation strategies for decaying collections, safekeeping and long term access to the endangered written cultural heritage is one of the most important facts.
Najdeno v: ključnih besedah
Ključne besede: paper, size exclusion chromatography, kinetics, deacidification process
Objavljeno: 02.09.2016; Ogledov: 2824; Prenosov: 180
Polno besedilo (1,33 MB)
STRUCTURAL PROPERTIES OF MANGANESE-FUNCTIONALIZED SILICA AEROGELSTatjana Kobal
, 2016, magistrsko delo
Opis: Manganese-functionalized silica with interparticle mesoporosity and isolated Mn sites (Mn/Si = 0.01) is an excellent Fenton catalyst for water cleaning. However, there is a problem that needs to be solved, i.e., Mn leaching from the silica support during the reaction. The solution may lie in using aerogels as the silicate supports for the manganese. The goal of this master thesis is the synthesis and characterization of manganese-functionalized silica aerogels with different Mn/Si molar ratios and a determination of their structural properties. The emphasis is on the preparation of manganese-functionalized silica aerogels with isolated manganese sites.
Firstly, manganese-functionalized microporous and mesoporous silicates with a molar ratio Mn/Si = 0.005–0.02 were synthesized according to the literature and characterized as reference materials for manganese-functionalized aerogels. Manganese silicalite-1 (MnS-1) as a microporous zeolite-type silicate and manganese-functionalized silica (MnKIL-2) as a mesoporous silicate were prepared by the sol-gel process with a hydrothermal and solvothermal treatment, respectively. MnS-1 and MnKIL-2 with a molar ratio of Mn/Si ≤ 0.01 contain manganese as isolated sites in the silica framework and with a molar ratio of Mn/Si > 0.01 contain manganese as manganese oxides.
Secondly, manganese-functionalized aerogels (MnAEG) with a molar ratio Mn/Si = 0.005–0.02, were prepared according to the acid-base of the sol-gel polymerization of a tetraethylorthosilicate precursor, which is followed in combination with a supercritical drying using CO2. The prepared materials were characterized using the following techniques: X-ray powder diffraction (XRD), energy-dispersive X-ray elemental analysis (EDX), nitrogen physisorption, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The characterization results on manganese-functionalized aerogels (MnAEG) showed Mn oxide nanoparticles incorporated into the aerogel already at a low Mn concentration (Mn/Si = 0.005), which means that Mn aerogels are not promising silica supports for Mn catalysts applied for water cleaning, because they do not contain isolated Mn sites.
Najdeno v: ključnih besedah
Povzetek najdenega: ...mesoporous silicate were prepared by the sol-gel process with a hydrothermal and solvothermal treatment, respectively....
Ključne besede: : SiO2 aerogels, manganese-functionalized SiO2 aerogels, sol–gel process, CO2 supercritical drying
Objavljeno: 02.09.2016; Ogledov: 2651; Prenosov: 147
Polno besedilo (4,37 MB)
General framework for the conservation of historical rural landscape. Case study of Qadisha Valley in Lebanon.Bachir Zarif Keyrouz
, 2016, doktorska disertacija
Opis: The international community has reacted to the challenges faced by historic cities and cultural landscapes. In 2011, UNESCO adopted the international recommendation on the Historic Urban Landscape in order to draw the attention of governments and local communities to the need to improve the management of historic urban areas. The aim of the present dissertation is to expand the UNESCO definition to Historic Rural Landscapes, and to explore how the proposed methodology could be applied to the management of rural areas. The dissertation takes the Qadisha Valley in Lebanon as an example, where some elements have already been recognised for their outstanding universal value. It is considered however that these historic-cultural elements are part of the larger context of the Qadisha Valley, which has its specificity and its qualities that merit being recognised. It is also considered that the management of the elements already recognised by UNESCO can only be successfully safeguarded if the management is understood in the context of the entire valley. Consequently, the thesis is articulated taking into account the following parameters:
1. UNESCO has already set the restoration plan to solve the problems of Qadisha Valley. Based on this plan, the question can be raised whether or not the rural planning in Qadisha is well managed at the present?
2. In case Qadisha Zone is not well conserved, what improvements could be brought about and implemented in order to safeguard the cultural heritage and historical rural landscape, and what should be the guiding policies of restoration?
3. Once a restoration plan is implemented in Qadisha Zone, what management plan should be brought up and implemented to safeguard its cultural heritage and historical rural landscape?
4. How can conservation of cultural heritage in Qadisha Zone be done culturally and in a socially acceptable way?
5. What sectors of the nation are to be involved in the Management plan? How can the MP preserve and restore Qadisha Zone?
The aim of the dissertation has been to examine the possibilities of involvement of the local community and relevant authorities in a more structured management of their properties within the context of the entire valley and its exceptional historic and landscape qualities. It is hoped that the study can generate more interest in the management of the rural context within the increasingly globalising society, and draw attention to the qualities of historic rural landscapes as the setting for an improved quality of life.
Najdeno v: ključnih besedah
Ključne besede: Historic Rural Landscape, Qadisha World Heritage, Heritage Community, Sustainable Tourism, Strategic Urban Management, Outstanding Universal Values & Conservation Process.
Objavljeno: 07.10.2016; Ogledov: 2578; Prenosov: 39
Polno besedilo (58,03 MB)
Transparent titania-zirconia thin films for self-cleaning and photocatalytic applicationVlasta Brezová
, Kandalam Ramanujachary
, Nives Vodišek
, Urška Lavrenčič Štangar
, 2016, objavljeni povzetek znanstvenega prispevka na konferenci
Opis: Thin films were prepared by sol-gel process, where different amount of zirconia were added to titania.
Photocatalytic activity of thin films was measured by two methods i) determination of degradation ration of methyl stearate with measuring the contact angle and ii) formation of hydroxyterephthalic acid was measured by spectrofluorometer.
Prepared samples were characterized by UV-Vis spectrophotometer, SEM, XRD, FT-IR ATR, and BET.
The result of measurements of photocatalytic activity shows that the highest activity has a sample without addition of zirconia, but mechanical stability of that sample is worse.
Najdeno v: ključnih besedah
Povzetek najdenega: ...Thin films were prepared by sol-gel process, where different amount of zirconia were added...
Ključne besede: photocatalysis, ZrO2/ TiO2, thin films, self-cleaning, low-temperature, sol-gel process
Objavljeno: 14.03.2017; Ogledov: 1879; Prenosov: 111
Polno besedilo (462,52 KB)
THE IMPACT OF EUROPEANISATION ON THE NATURE PROTECTION SYSTEM OF SELECTED COUNTRIES OF SOUTHEAST EUROPE ON THE EXAMPLE OF THE ESTABLISHMENT OF MULTI-LEVEL GOVERNANCE SYSTEM OF NATURA 2000Aleksandar Šobot
, 2017, doktorska disertacija
Opis: The Europeanisation of Southeastern Europe led to the pre-accession and accession process of joining countries of the former Yugoslavia to the European Union. Slovenia's accession to the formal process of accession to the European Union started in 1999. This process lasted until 2003. Then, in 2004, Slovenia joined the European Union. Croatia's access to the formal process of accession to the European Union started in 2003. This process lasted until 2012. Then, in 2013, Croatia joined the European Union. Bosnia and Herzegovina entered the pre-accession process with the process of stabilization and association with the European Union, which lasted from 1999 to 2015. Then, in 2016, Bosnia and Herzegovina officially submitted its application for European Union membership.
This paper examines the impact of the Europeanisation during this period on the nature protection system in the case of Slovenia, Croatia and Bosnia and Herzegovina while establishing multi-level governance system of protected areas within NATURA 2000 network. The analysis of the establishment of multi-level governance system is performed according to the morphogenetic model in three cycles as a case study. The case study is organized with the help of interviews and desk analysis of the relevant documents. In the first cycle were explained the projects/process of implementation of NATURA 2000 in Slovenia, Croatia and Bosnia and Herzegovina and its changing impacts on national legislation in the area of nature protection (environmental policy). The second cycle explains the role of the main actors in the establishment of multi-level governance system of NATURA 2000 such as the European Union institutions, competent ministries, national parks and non-governmental organisations (environmental polity). The third cycle outlines the contribution to the establishment of multi-level governance system of NATURA 2000 on the nature protection systems of Slovenia, Croatia and Bosnia and Herzegovina and their future challenges (environmental politics).
The main conclusions point to the major changes in the nature protection systems of Slovenia, Croatia and Bosnia and Herzegovina during the process of implementation/establishing multi-level governance system of NATURA 2000. Main legal and institutional points of implementation of NATURA 2000 with all positive and negative sides are presented here. In the end, implementation of the European ecological network NATURA 2000 in Slovenia is marked as an excellent example with significant changes in legal (laws on nature protection) and institutional (transformation of governmental institutions, establishment of new institutions and inclusion of NGOs in decision making) framework. This process in Croatia was marked as good with significant changes in legal (laws on nature protection, adopting new strategy of sustainable development) and institutional (transformation of governmental organisation, establishment of new institutions and inclusion of NGOs in decision making) framework. This process in Bosnia and Herzegovina was marked as satisfactory with significant changes in legal (adopting new entity laws on nature protection) and institutional (adopting coordination mechanism for inter-entity and inter-institutional cooperation as well as inclusion of NGOs in decision making) framework.
There are also significant weak points during the process of N2000 in all three countries (such as the late change of national legislative, not following the national legislative from governmental institution and not including NGOs into decision making), which during the proces of implementation of N2000 (for Croatia and Slovenia) or the process of preparation of implementation (for Bosnia and Herzegovina) cause significant problems, that call for action in the future in order to improve governance of natural resources /NATURA 2000. On the other hand, these points could serve as an example for all countries that underwent/or should undergo ...
Najdeno v: ključnih besedah
Povzetek najdenega: ...Europe led to the pre-accession and accession process of joining countries of the former Yugoslavia...
Ključne besede: The Europeanisation of Southeastern Europe, the pre-accession process, the accession process, Slovenia, Croatia, Bosnia and Herzegovina, the nature protection system, NATURA 2000 protected areas
Objavljeno: 06.11.2017; Ogledov: 1561; Prenosov: 167
Polno besedilo (2,77 MB)