Novel Inorganic–Organic Luminescent Materials by Atomic/Molecular Layer Deposition

Luminescent hybrid inorganic-organic materials form an exciting material family used for light generation, conversion, and amplification. Chromophores coupled to lanthanides in such type of materials are responsible for the efficient energy transfer to the emitting lanthanide ions. Integration of the inorganic and organic components in the atomic/molecular scale results in hybrid nanostructures enabling new luminescent, electronic and optoelectronic properties. The controlled deposition of these materials on complex surface architectures is a yet unresolved issue, which is essential for the next-generation luminescent nanodevices, such as medical detection devices, photovoltaic solar panels, and light-emitting diodes. However, quite a few synthetic techniques of this kind exist. To address this gap, novel atomic/molecular deposition (ALD/MLD) processes have been developed in recent years. The strongly emerging ALD/MLD technique has the advantage of linking the inorganic and organic layers into hybrid nano-networks with their thicknesses and compositions controlled within atomic/molecular level precision. It is the only available gas-phase deposition technique to produce such hybrid materials. In this thesis, various inorganic and organic ALD/MLD precursors were studied with the aim to produce new luminescent hybrid inorganic-organic materials. The deposition of red-emitting phosphor represents the first described ALD/MLD made lanthanide-based luminescent hybrid material. Here, two different aromatic pyridine dicarboxylic acids were investigated as organic precursors together with Eu(thd)3. Oxygen-based 1,4-benzene dicarboxylic acid was used for comparison. Furthermore, the mixed (Y0.92Yb0.04Er0.04)(thd)3 precursor was used for the depositions together with 2,3-pyrazine dicarboxylic acid. Nucleic acid bases (uracil and adenine) were utilized for the first time as exciting natural organic precursors together with Na(thd), Ba(thd)2 and La(thd)3 metal precursors. For all the ALD/MLD processes investigated conditions were found under which the processes occurred based on well-controlled self-limiting surface reactions and yielded amorphous or crystalline hybrid thin films with growth rates typically ranging from 1 to 10 Å/cycle. The new lanthanide-based hybrid materials exhibited high luminescent intensities in the visible and near-infrared regions. The best luminescent intensities were achieved due to by-coordination to N and O of pyridine carboxylates. Furthermore, the (Y,Yb,Er)-based hybrid materials demonstrated upconverting properties with all the three main colours (red, green and blue). The nucleobases were found to form hydrogen-bonded hybrid networks which showed emission in the visible range, the color changing from blue (Na) to green (Ba) and greenish blue (La) depending on the metal constituent. Hydrogen bonding between the inorganic and organic moieties moreover caused the so-called red-edge shift (REES) effect rarely seen for conventional materials.

Mars and Venus in Action? The US and EU’s foreign relations strategies in academic discourse

[full article and abstract in English] This article reviews the existing academic literature that compares and explains the differences between the US and the EU’s external actions. An analytical matrix is devised to group publications by level of analysis (micro-, mid-, and macro) and by theme of comparison criteria. The key findings are that in the macro level of analysis, authors tend to compare the role actors have in international relations before claiming either that the EU is a different kind of power due to its peculiar historical experience, or that the EU is weak due to its complicated structure and lack of military capacities. Furthermore, authors conducting their analyses at the micro level tend to find more similarities between the EU and the US’s external actions than those working at the macro level. The article concludes by making a point in favour of further comparisons as an essential tool to better understand the EU and other actors in international relations.[straipsnis ir santrauka anglų kalba

Imperio, liderazgo o hegemonía: estrategias de Estados Unidos hacia los países del Triángulo Norte en el siglo XXI

The goal of this article is to conceptualize the US strategies towards the Northern Triangle countries during 2005–2015. Using Destradi’s framework of regional power strategies, this paper analyses strategic documents and secondary sources regarding how US defined goals of its regional cooperation and means for their achievement. It concludes claiming that the US strategy towards the region can be called hegemonic as it was openly subordinated to its needs. Nevertheless, there has been a shift from hard to intermediate hegemony as the US became more perceptive to the needs of its regional partners.El artículo sistematiza las estrategias de los EE. UU. hacia los países del Triángulo Norte, siguiendo la categorización de Destradi. Para ello, se ha analizado el contenido de los documentos estratégicos para identificar como los EE. UU. definen sus objetivos en cuanto a la cooperación regional y las medidas para conseguirlos. El texto concluye con la afirmación que la estrategia de los EE.UU. hacia la regi ón puede definirse como hegemónica, sin embargo, progresivamente se ha cambiado de dura a intermedia, a medida que los EE.UU. se hicieron más perceptivos a las necesidades de sus socios regionales

Thorium fuel cycle economics

This thesis examines potential of thorium as a nuclear fuel for High Temperature Reactors (HTRs). It aims to analyse fuel cycle based on specific mixture of thorium and the additional fissile material. Two important contributors to the fuel cycle costs are: uranium ore price and enrichment which contribute to 75 % over the total fuel cycle costs. Reduction of U235 enrichment requirements, improved fissile fuel utilization (high conversion ratio) and enlargement of fissile resources (breeding U233 from Th) can be achieved by application of thorium fuel cycle. The need for reactors with better proliferation-resistance, longer fuel cycles, higher burn up, improved waste form characteristics, and reduction of plutonium inventories and the possibility of in-situ use of bred fissile material has led to renewed interest in thorium - based reactors. In a pebble - bed HTR the different fuel particles, Plutonium (Pu) on the one hand and Thorium (Th) and Uranium (U) on the other hand can be loaded also into different fuel elements, which are continuously loaded and disloaded. In this thesis the following fuel cycle mixtures were examined: Th-U, Th-Pu, and pure U. ThO2 and PuO2 for a pebble - bed High Temperature Reactor are in general intended to incinerate plutonium and minor actinides provided by discharged and reprocessed fuel of Light Water Reactors and to breed the new suitable fissionable material U233. I have made a comparison between the once - through and closed thorium - uranium fuel cycles. For assessment I have used a standard Present Worth Cost method. The previous fuel cycle studies conducted by E. Teuchert have shown that there are no significant differences between thorium and uranium fuel cycles costs. My calculations have shown similar results. The parameters can be optimized in the reactor design favourably for both fuel cycles pure uranium and thorium mixed with uranium or plutonium

Identification and validation of risk factors in cold work

There are very few methods available for the assessment of cold exposure and they rely more or less on complex equations for calculating heat balance; therefore, there is a need for new practical methods for the identification and control of cold hazards in workplaces. In the first study, the aim was to test a checklist which enables cold risk assessment based on observations in the workplace. The checklist has seven main sections of cold related risk factors: ‘cold air’, ‘wind/air movements’, ‘contact with cold surfaces’, ‘exposure to water/ liquids/moisture’, ‘protective clothing against cold’, ‘protection of hands/feet/head from cold’ and ‘the use of personal protective equipment’. A total of 82 evaluation sheets were obtained from the field testing (24 from Sweden and 58 from Finland). The subjects found the observational checklist to be a usable tool for cold risk assessment in terms of the time needed to perform the risk assessment procedure, the interference of the method with the observed work, the adequacy of the instructions and the facility of the checklist. In the second study, the aim was to test the checklist at workplaces in a country representing a different approach to safety culture than the one prevailing in Scandinavian countries. A secondary objective was to test whether there was a learning effect reflected in the results recorded in the evaluation sheets when filled in after conducting the cold risk assessment procedure for the first, second and third time. A total of 277 evaluation sheets were obtained from 116 observers from two sawmills in north-western Russia. The observers, similarly to the ones in Finland and Sweden, found the observational checklist to be a usable tool for cold risk assessment in terms of the time needed to perform the risk assessment procedure; the instructions provided for the checklist and to the summary table; the facility of the checklist and summary table and the suitability of the checklist (in regards to the structure and content) in identify cold- related risk factors. According to the Nordic observers, a workers’ representative responsible for industrial safety and the workers themselves should carry out the assessment procedure at the workplace. On the contrary, the Russian observers mentioned workers only in 7.5% of the evaluation sheets, giving priority to a safety engineer (mentioned in 50.5% of evaluation sheets) and a foreman (mentioned in 22.6% of evaluation sheets). No statistically significant effects of learning were found when three groups of answers (after the first, second and third time) were compared (N=73). In the third study, the objective was to validate the checklist for the identification of cold-related problems under laboratory conditions in terms of whether the checklist generated results were in accordance with the subjects’ physiological measurements and self-reported observations of their thermal state. Eight male subjects were screwing bolts with both gloves and bare hands and stepping in 0C, walking at 3.5 km/hour and 4.9 km/hour in -10C and at 3 km/hour in -25C and standing still at +4C in the climatic chamber. In conclusion, the number of subjects who assessed the particular cold related risk factor by means of the checklist in conformity to their reported thermal sensations and measured skin temperatures varied most often from five to eight subjects. In some rare cases, only one, two or three subjects gave evaluations that were in agreement. In particular, this was the case for risk factors concerning the presence of light work and protection of extremities against cold, when several work tasks were performed under the same experiment. In the fourth study, the aim was to identify cold-related risk factors that people face in their work environment and to investigate whether the region where the checklist was filled in, the type of work (indoor versus outdoor work), ambient temperatures and the sector that the company represented had any influence on the ratings that these factors received. Cold-related risk factors were assessed in 14 companies representing various work activities in construction, stevedoring and storage, tourism, sawmills, fish processing, forestry and road building industries in four countries: Finland, Norway, Sweden and north-western Russia. An observational checklist for the assessment of 13 cold-related risk factors was applied and 164 checklists were filled in by 80 selected observers in the Nordic countries and 277 checklists were completed by 116 selected observers in north-western Russia. The observers consisted of worksite managers, occupational health and safety (OH&S) representatives, occupational nurses and the workers themselves. The majority of the cold-related risk factors were rated differently by Nordic and Russian observers in term of either the chosen severity of the problem (‘no problem’, ‘slight problem’ or ‘considerable problem’) or the frequencies of ratings along these categories. Five factors (‘cold air’, ‘wind/ air movements’, ‘contact with cold surfaces’, ‘water/ liquids/ damp’ and ‘highly varying workload’) were most often rated as slightly problematic and two factors (‘protective clothing against cold’ and ‘light work’) as causing no problems by both groups. The remaining six factors (‘protection of extremities against cold’, ‘use of PPE’, ‘long-term cold exposure’, ‘varying thermal environments’, ‘slipperiness’ and ‘insufficient lighting’) were rated differently by Nordic and Russian observers, and the latter indicated less favourable situations at the observed workplaces. Only a few factors had different ratings if various variables (nature of work, ambient temperatures and sector of economic activities) were taken into account. In the fifth study, the aim was to validate the Edholm scale and the ISO 8996 standard by comparing the metabolic rates estimated for both methods with the actual measured metabolic rate (M_Meas) in six manual material handling tasks simulated under laboratory conditions. The metabolic rate was calculated from the oxygen consumption VO2 (19 participants) according to Standard No. ISO 8996. Additionally, the subjects estimated perceived exertion using the Borg scale. The metabolic rates derived from the Edholm scale (M_Edh) overestimated five of six activities by 34-50% (significance level .05). The metabolic rates derived from ISO 8996 (M_ISO) overestimated all activities by 7-38% (significance level .05).Godkänd; 2005; 20061002 (ysko

Stained and painted glass in the Sydney area c. 1830 - c. 1920

Dissertação de mestrado em Psicologia Clínica e da Saúde (Intervenções Cognitivo-Comportamentais nas Perturbações Psicológicas e da Saúde), apresentada à Faculdade de Psicologia e de Ciências da Educação da Universidade de CoimbraO conflito trabalho-família, devido às mudanças demográficas dos últimos anos e aos desafios da economia actual, afecta um número cada vez mais significativo de pessoas. A literatura descreve consequências negativas do conflito trabalho-família em resultados de saúde e bem-estar individuais e familiares, sendo que uma das lacunas da investigação até à data é a identificação de factores protectores das referidas consequências. Ao nível do contexto familiar, os rituais familiares têm sido apontados como factores importantes para a adaptação, nomeadamente em situações de stress familiar. Assim, o principal objectivo deste estudo foi examinar as associações entre conflito trabalho-família, significado atribuído aos rituais familiares, qualidade de vida e qualidade relacional; examinouse ainda o papel moderador do significado atribuído aos rituais familiares nas associações entre conflito-trabalho família e outcomes individuais e relacionais. A amostra foi constituída por 255 trabalhadores em situação profissional activa, casados ou em união de facto, dos quais 135 eram mulheres e 120 eram homens. Todos preencheram questionários de auto-resposta que avaliavam o conflito trabalho-família, o significado atribuído aos rituais familiares, a qualidade de vida e a qualidade relacional. O conflito trabalho-família estava negativamente associado ao significado atribuído aos rituais familiares, à qualidade de vida e à qualidade relacional. O significado atribuído aos rituais familiares estava positivamente associado à qualidade de vida e à qualidade relacional. Os participantes com tipo de horário laboral por turnos reportaram maior interferência do trabalho na família devido ao tempo. Adicionalmente, os resultados evidenciaram que um nível mais elevado de significado atribuído aos rituais familiares estava associado a menor impacto do conflito trabalho-família devido ao tempo na qualidade relacional dos homens, mas não das mulheres. As implicações dos resultados deste estudo são discutidas considerando os efeitos promissores dos rituais familiares para a saúde e bem-estar de indivíduos profissionalmente activos que se encontram numa relação de casamento ou de união de facto.Work-family conflict affects an increasingly large number of persons due to the demographic changes in recent years and to the challenges of the current economy. The literature describes the negative consequences of work-family conflict on family and individual health and well-being outcomes. One of the gaps in research to date is the identification of protective factors of such consequences. In the family context, family rituals have been identified as relevant to adaptation, particularly in situations of family stress. Thus, the main objective of this study was to examine the associations between work-family conflict, family ritual meaning, quality of life and relationship quality; we also examined the moderating role of family ritual meaning in the associations between work-family conflict and individual and relational outcomes. The sample consisted of 255 active workers, 135 women and 120 men who were married or in a cohabiting union. All participants completed self-administered questionnaires assessing work-family conflict, family ritual meaning, quality of life and relationship quality. Work-family conflict was negatively associated with family ritual meaning, quality of life and relationship quality. Family ritual meaning was positively associated with quality of life and relationship quality. Shifts’ workers reported higher interference of work in the family due to time. Additionally, the results showed that a higher level of family ritual meaning was associated with a weaker association between work-family conflict due to time and relationship quality in men, but not women. The implications of this study’s findings are discussed in light of the promising effects of family rituals for the health and well-being of individuals currently employed and in a marriage/coabiting relationship

Flexible inorganic-organic thin-film phosphors by ALD/MLD

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