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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Propriedades físicas de snacks e farinhas pré-gelatinizadas de coprodutos de arroz e soja em função das variáveis de extrusão / Physical properties of snacks and pre-gelatinized flour byproducts of rice and soybeans in terms of the variables extrusion

Coutinho, Lairy Silva 08 July 2013 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-10-30T20:37:57Z No. of bitstreams: 2 Dissertação - Lairy Silva Coutinho - 2013.pdf: 3072078 bytes, checksum: 9e9c2f3a2bf45cb601d6984d4246199d (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2014-10-31T09:29:39Z (GMT) No. of bitstreams: 2 Dissertação - Lairy Silva Coutinho - 2013.pdf: 3072078 bytes, checksum: 9e9c2f3a2bf45cb601d6984d4246199d (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-10-31T09:29:39Z (GMT). No. of bitstreams: 2 Dissertação - Lairy Silva Coutinho - 2013.pdf: 3072078 bytes, checksum: 9e9c2f3a2bf45cb601d6984d4246199d (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-07-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The rice processing industries currently designed its most byproducts generated during processing, such as rice bran and broken rice grains for animal feed. However, they are nutritionally rich and interesting human consumption. Therefore, it becomes interesting to use these for the development of new products. The soy industry also uses okara (residue coming from the aqueous extract of soy) more for animal feed. For human consumption is less used, although it has high content of protein, lipids and is a source of energy. Thus, this study aimed to formulate snacks and pre-gelatinized flour with coproducts broken grains and rice bran and soybean okara black and study the effect of extrusion variables (temperature and humidity) on the physical, chemical and technological characteristics of products, processed under various humidity (12 to 20 g.100 g-1) and extrusion temperatures (60 to 110 °C). For these analyzes was used official methodologies. Was performed desirability of snacks considering expansion index, specific volume and color parameter chroma a *. The snack of higher desirability was prepared at moisture condition in the mixture of 12 g.100 g-1 and at temperature of 85 ° C. As for the pre-gelatinized flour, moisture conditions for extrusion of mixtures influenced the viscoamilograficos aspects and texture, and milder temperatures employed were obtained with higher values of initial viscosity (above 4000 cP), final viscosity (above 5500 cP) and setback (above 4500 cP). The absorption and solubility in water and oil absorption are also affected, and the higher results in higher extrusion temperatures and lower humidities. The pre-gelatinized flour byproducts of rice and soybeans can be an alternative to the industry by adding value to them, which after processing will enable the development of an ingredient in many products for human consumption. / As indústrias de beneficiamento de arroz atualmente destinam a maior parte dos coprodutos gerados, tais como farelo de arroz e grãos quebrados de arroz para as indústrias de ração animal. Porém, esses são ricos nutricionalmente e interessantes ao consumo humano. Portanto, torna-se interessante o seu aproveitamento para desenvolvimento de novos produtos. A indústria de soja também utiliza o okara (resíduo oriundo do processamento do extrato aquoso da soja) mais para ração animal. Para alimentação humana é menos utilizado, embora possua alto teor de proteína, lipídeos e seja fonte de energia. Assim, este trabalho objetivou formular snacks e farinhas pré-gelatinizadas com os coprodutos grãos quebrados e farelo de arroz e okara da soja preta e estudar o efeito das variáveis de extrusão (umidade e temperatura) sobre as características físicas, químicas e tecnológicas desses produtos, processados sob diferentes umidades (12 a 20 g.100 g-1) e temperaturas de extrusão (60 a 110 °C). Para estas análises utilizaram-se metodologias oficiais. Foi realizado desejabilidade dos snacks considerando índice de expansão, volume específico e parâmetro de cor croma a*. O snack de maior desejabilidade foi elaborado na condição de umidade da mistura de 12 g.100 g-1 e temperatura de 85 °C. Quanto à farinha pré-gelatinizada, as condições de umidade das misturas para extrusão influenciaram nos aspectos viscoamilográficos e de textura, sendo que nas temperaturas empregadas mais brandas se obtiveram valores mais elevados de viscosidade inicial (acima de 4000 cP), viscosidade final (acima de 5500 cP) e tendência a retrogradação (acima de 4500 cP). A absorção e solubilidade em água e absorção de óleo também foram influenciadas, sendo os maiores resultados obtidos sob temperaturas de extrusão mais elevadas e umidades mais baixas. A farinha pré-gelatinizada dos coprodutos de arroz e soja pode ser uma alternativa para a indústria, por agregar valor a estes, que depois de processados poderão possibilitar o desenvolvimento de ingredientes para diversos produtos para alimentação humana.
132

Aproveitamento de subproduto do beneficiamento de arroz: desenvolvimento de farinha modificada como alternativa para a indústria de panificação / Utilization of by-product of rice milling: development of modified flour as an alternative to the bakery industry

BAIOCCHI, Marise Leão Marques 31 August 2011 (has links)
Made available in DSpace on 2014-07-29T15:22:53Z (GMT). No. of bitstreams: 1 Dissertacao Marise Baiocchi pdf.pdf: 2686545 bytes, checksum: fa6d2bd3bf12cca6123d5cec87748310 (MD5) Previous issue date: 2011-08-31 / Brazil is one of the largest rice producers in the world. The aim of this study was evaluate the best conditions of fermentation and development of modified rice flour with oven expansion property, as well as to describe its physical, chemical and microbiological characteristics. In the first part of this study, 12 samples, of broken rice granules, were fermented with different concentrations of sour cassava starch inoculum in different periods of time. The analysis evaluated the pH, acidity, expansion and paste properties. The results showed that pH was influenced by the period of fermentation, but not by the concentration of inoculum in all samples at the same period of time. The acidity was influenced by both variables. The expansion was not influenced by the period of fermentation related with concentration, in almost all samples. Only the sample with 2g 100g-1 of inoculum and 48 hours period of fermentation revealed a significant tendency model, R2 83,3%. There were also relevant differences in the paste properties profile in relation to the control flour (CF) (with no fermentation), in some samples. At the second part of the research, the MF with the best oven expansion capability was compared physically and chemically with the CF. There has been significant rise in acidity, pH and expansion in the MF in relation to CF. The humidity was kept in the limits established by the Brazilian legislation. The swelling power did not vary significantly among the samples, increase of 155% in WSI was observed on MF in relation to CF. The MF had significant loss of protein and ashes and alterations in the mineral profile. Fermentation caused a rise of amylose content. The electronic microscope scan revealed alterations in the structure and surface of the starch granules of MF. In microbiological terms, MF can be considered safe for human consume, with minimum shelf life of 90 days. According with the limits established by Brazilian legislation, it is safe for human consume. As a conclusion, MF can be a new alternative for the bakery industry products with expansion properties differentiated physical and chemical characteristics. / O Brasil é um dos maiores produtores mundial de arroz. No processo de beneficiamento são gerados grãos quebrados aproveitados na alimentação humana e quirera que é destinada a outros fins e poderia ser melhor utilizada na forma de farinha modificada (FM), por sua composição centesimal, semelhante a do arroz polido. O objetivo deste trabalho foi avaliar as melhores condições de fermentação e desenvolver uma farinha modificada com capacidade de expansão, assim como caracterizar física, química e microbiologicamente a farinha obtida. Na primeira parte do experimento foram realizados 12 ensaios, com diferentes concentrações de inóculo de polvilho azedo e em diferentes tempos de fermentação. Foram realizadas análise de pH, acidez, expansão e perfil viscoamilográfico. Os resultados indicam que o pH, foi influenciado pelo tempo de fermentação, mas não pela concentração de inóculo em todos os ensaios. A acidez foi influenciada pelas duas variáveis. A expansão ao forno não foi influenciada pelo efeito do tempo de fermentação em relação à concentração em quase todos os ensaios, somente o tratamento com 2g 100g-1 de inóculo e tempo de fermentação de 48 horas apresentou modelo de tendência significativo, R2 de 83,3%. Foram encontradas, diferenças significativas do perfil viscoamilográfico em relação à farinha controle FC (farinha controle sem fermentação), e entre alguns tratamentos. Na segunda parte, a FM com a melhor condição de expansão foi comparada física e quimicamente com a FC. Observou-se aumento significativo da acidez, pH e expansão na FM em relação a controle. As umidades ficaram dentro dos limites estabelecidos pela legislação Brasileira. O índice de absorção de água (IAA) não diferiu significativamente entre as farinhas, ocorrendo aumento de 155% no índice de solubilidade em água (ISA) da FM em relação à FC. A FM teve perda significativa de proteínas e cinzas e alteração no perfil mineral. A fermentação ocasionou aumento do teor de amilose. Na microscopia eletrônica de varredura, observou-se alterações na estrutura e superfície dos grânulos de amido da FM. Sob o ponto de vista microbiológico, a FM pode ser considerada segura para alimentação humana, com vida mínima de prateleira de 90 dias. Ficando dentro dos limites de segurança estabelecidos pela legislação. Conclui-se dessa forma que a FM pode ser uma nova alternativa para produção de produtos de panificação com características de expansão diferenciada.
133

Digestibilidade de alimentos energéticos suplementados com fitase para o jundiá (Rhamdia voulezi) / Digestibility of energetic feeds supplemented with phytase for catfish (Rhamdia voulezi)

Lewandowski, Vanessa 27 February 2015 (has links)
Made available in DSpace on 2017-07-10T18:13:18Z (GMT). No. of bitstreams: 1 Vanessa Lewandowski.pdf: 762023 bytes, checksum: 7429ef66529d330e89eb20c8a3620f23 (MD5) Previous issue date: 2015-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of the study was to evaluate the digestibility of oat, rice grits, and wheat middling nutrients by silver catfish (Rhamdia voulezi), with and without phytase supplementation. We used 288 fish distributed in 24 tanks of 500 L with tapered conical bottom. The experimental design was completely randomized represented by eight treatments and three replications. The treatments consisted of two reference diets (reference with and without phytase) and six test diets (oats with and without phytase, rice grits with and without phytase and wheat middling with and without phytase), factorial design, obtaining four diets without enzyme supplementation and four diets with supplementation. In the supplemented diets we added 1500 FTU kg-1 of phytase. We performed chemical, physical and mineral (phosphorus, calcium, magnesium, iron and cupper) analysis of the ingredients, diets and feces, as well as chromium oxide measurement of the diets and feces. The digestibility coefficients observed were submitted to factorial variance analysis (P>0,05). When a significant effect was observed, the Tukey s test was performed for mean comparisons. Oat presented the lowest digestibility coefficients for dry matter and energy compared to the other feeds supplemented or not with phytase. Phytase supplementation increased the digestibility coefficient of dry matter for rice grits, and of energy both for this feed and for wheat middling. As for the use of minerals we verified that wheat middling presented the highest digestibility coefficients related to feed without phytase as much as for feed supplemented with the enzyme. The supplementation of phytase in quantity of 1500 FTU kg-1 in the diet improves the nutrients digestibility coefficients mainly for oat and rice grits. Taking into account the feeds with or without supplementation of 1500 FTU kg-1 in the diet, rice grits and wheat middling presented the highest values of its nutrients use and can be used more efficiently for silver catfish (R. voulezi) feeding. / O objetivo do estudo foi avaliar a digestibilidade de nutrientes da aveia, quirera de arroz e do triguilho pelo jundiá (Rhamdia voulezi), com e sem suplementação de fitase. Foram utilizados 288 peixes distribuídos em 24 tanques de 500 L com fundo cônico afunilado. O delineamento experimental foi inteiramente casualisado, representado por oito tratamento e três repetições. Os tratamentos consistiram na elaboração de duas dietas referências (referência com e sem fitase), e seis dietas testes (aveia com e sem fitase, quirera de arroz com e sem fitase e triguilho com e sem fitase), em esquema fatorial, obtendo-se quatro dietas sem suplementação da enzima e quatro dietas com suplementação. Nas dietas suplementadas, foi utilizado 1500 FTU Kg-1 de fitase. Foram realizadas análises físico-químicas e de minerais (fósforo, cálcio, magnésio, ferro e cobre) dos ingredientes, dietas e fezes e realizou-se leitura de óxido de crômio das dietas e das fezes. Os coeficientes de digestibilidade observados foram submetidos à análise de variância fatorial (P>0,05). Ao constar efeito significativo foi realizado o teste de Tukey para comparação de médias. A aveia apresentou os menores coeficientes de digestibilidade para a matéria seca e energia em relação aos demais alimentos suplementados ou não com fitase. A suplementação de fitase aumentou o coeficiente de digestibilidade da matéria seca para a quirera de arroz e da energia tanto para esse alimento como para o triguilho. A suplementação enzimática apresentou maior influência na disponibilidade dos minerais para a aveia, entretanto, o triguilho apresentou os maiores coeficientes de digestibilidade dos mesmos, tanto em relação aos alimentos sem fitase como aos alimentos suplementados com a enzima. A quantidade de 1500 FTU Kg-1 na dieta melhora os coeficientes de digestibilidade dos nutrientes principalmente para a aveia e quirera de arroz. Levando em consideração os alimentos suplementados ou não com 1500 FTU Kg-1 na dieta, a quirera de arroz e o triguilho apresentam valores maiores de aproveitamento de seus nutrientes podendo ser utilizados de forma mais eficiente na alimentação do jundiá (R. voulezi).
134

ČaɁak (Islands): how place-based Indigenous perspectives can inform national park ‘visitor experience’ programming in Nuu-chah-nulth traditional territory

Helweg-Larsen, Kelda Jane 02 May 2017 (has links)
This research project explores ways in which place-based Indigenous perspectives can inform national park ‘visitor experience’ planning, management, and information delivery. Engaged in collaborative processes with Tseshaht First Nation, this project explores knowledge of Tseshaht-identified places of cultural significance in Tseshaht traditional territory, discussed in the context of creating a web-based digital map. In attempting to explore Nuu-chah-nulth-informed ways in which to more widely share cultural history and knowledge in Pacific Rim National Park Reserve, I learned of the many dynamics that are revealed when the depth of Nuu-chah-nulth connections to place are made visible. This research project examines knowledge, power, and place in the context of Indigenous self-representation. Informed by Indigenous ways of knowing and Indigenous principles of knowledge-sharing, this thesis is an ethnography of knowledge-sharing in modern contexts fraught with issues of state power, commodification, and colonialism. / Graduate
135

Effect of marital dissolution on early adolescents' academic and psycho-social development

Mauki, Chrissiona January 2014 (has links)
This study investigated marital dissolution in the Tanzanian context. The study specifically focused on the potential effect of marital dissolution (both positive and negative) on early adolescents’ academic and psycho-social functioning. The primary research question directing the research is: ―How can insight into marital dissolution in Tanzania broaden our knowledge on its effect on children?‖ The conceptual framework for the study is based on attachment theory, crisis theory, family stress theory and life course theory. Epistemologically, the study utilised social constructivism as paradigm. A qualitative methodological approach was followed, implementing an instrumental case study as research design. I purposefully selected eight children from two children’s centres in Tanzania and four additional children from custodial homes. In addition, twelve parents, who had been separated from their partners, as well as twelve teachers and caregivers who have been involved with the child participants, participated in the study. For data collection I employed semi-structured interviews with the parents and children; focus group discussions with teachers and caregivers; interviews and narrations with children; and an analysis of existing documents. Field notes, a research diary and verbatim transcripts were utilised to document the data I collected. Following inductive thematic analysis four themes emerged, relating to the reasons for marital dissolution, the effect of marital dissolution on early adolescents’ functioning, trends following marital dissolution and managing marital dissolution in Tanzania. In terms of reasons for marital dissolution I identified the following subthemes: abuse, lack of commitment to the family, influence of others, and financial strain. In terms of the effect of marital dissolution on early adolescents’ functioning three subthemes emerged namely; effect on early adolescents’ academic performance, effect on early adolescents’ psycho-social well-being, and parents’ insight into the effect of marital dissolution on their children. With regard to trends following marital dissolution I identified the following three subthemes: positive effect of marital dissolution, change in living arrangements, and other related changes negatively affecting children. Finally, two subthemes emerged concerning the management of marital dissolution in Tanzania, namely minimising the effect of marital dissolution on children, and potential role of the Tanzanian government. The findings of this study indicate that the majority of Tanzanian couples merely separate, rather than following a legal divorce. Parents showed limited insight into the effect of marital dissolution on their children. Besides some children experiencing the separation of their parents as a relief, the majority of children were negatively affected in terms of their academic performance and psycho-social functioning. Children indicated the need to be involved in discussions preceding and during the separation process, yet Tanzanian parents did not value the involvement of their children during this process. Based on the findings I obtained I conclude that the effect of marital dissolution on children are not only continuous but that the effects in various areas of functioning are interrelated and cyclic in nature, and that children can experience the effects before, during and after marital dissolution. / Thesis (PhD)--University of Pretoria, 2014. / lk2014 / Educational Psychology / PhD / Unrestricted
136

Mining in the settler dominions : a comparative study of the industry in three communities from the 1880s to the First World War

Mouat, Jeremy January 1988 (has links)
This dissertation examines the evolution of the mining industry in three British dominions during the late nineteenth and early twentieth centuries. Adopting a case study approach, it describes the establishment and growth of mining in Rossland, British Columbia; Broken Hill, New South Wales; and Waihi, New Zealand. Separate chapters trace developments in each area, focussing on the emergence of organised labour, the growth of mining companies and the sophistication of mining operations. These underline the need to consider diverse themes, maintaining that the mining industry's pattern of growth can be understood only by adopting such a broad approach. Following the three case studies, the final chapters of the dissertation offer a comparative analysis of Rossland, Waihi and Broken Hill. The study emphasises the similarities of these three communities, especially the cycle of growth, and identifies a crucial common denominator. Despite differences in climate, in the type and nature of the ore deposit and in the scale of mining activity, all three areas experienced a common trajectory of initial boom followed by subsequent retrenchment. The changing character of the resource base forced this fundamental alteration of productive relations. In each region, the mineral content of the ore declined as the mines went deeper. In addition, with depth the ore tended to become more difficult to treat. Faced with a decline in the value of the product of their mines, companies had to adopt sweeping changes in order to maintain profitable operations. This re-structuring was accomplished in a variety of ways, but the most significant factors, common to Rossland, Broken Hill and Waihi, were the heightened importance of applied science and economies of scale. Both developments underlined the growing importance of the mining engineer and technological innovations, principally in milling and smelting operations. In addition, new non-selective extractive techniques reduced the significance of skilled underground labour. The re-structuring of the industry not only had similar causes but also had a similar effect. The comparative chapter on labour relations, for example, argues that these managerial initiatives were closely associated with militant episodes in each community. While the leading companies in Rossland, Waihi and Broken Hill successfully reduced their working costs, they all faced the same ultimate end. Their long-term success or failure reflected the skill with which they coped with the inevitable depletion of their ore body. The common experience of Rossland, Waihi and Broken Hill demonstrates the importance of placing colonial development within a larger context. Regional historians should make greater use of the comparative approach, rather than continuing to focus on the unique and the particular. / Arts, Faculty of / History, Department of / Graduate
137

The Function of Social Structure in Controlling Violent Crime in Turkey

Guclu, Idris 12 1900 (has links)
This dissertation examines the relationship between social structural factors and violent crime rates in Turkey. The relationship between social structural characteristics and violent crime is worth exploring in areas that have attracted little academic attention, such as violent crime in Turkey. In order to understand and prevent the occurrence of crime, researchers have long investigated possible factors related to crime. Examining how crime varies across different regions can help us to understand underlying reasons for violent crime, which is considered one of the enduring problems in society. The findings of this research, to some extent, support the assumptions of social disorganization theory regarding the distribution of violent crime. Both the findings of multivariate and bivariate analysis indicated that poverty, unemployment, and family disruptions may have a positive effect on the distribution of violent crime in the cities of Turkey. The analysis of the effects of the social structure variables through the mediating variables, such as religious institutions, libraries and voluntary associations on the number of violent crimes and violent criminals, to some extent, support the tenets of social disorganization theory. However, all mediating variables cannot mediate all the indirect effects of social structural covariates. In brief, none of their indirect impacts on the social structural variables on the outcome variable was significant via mediating variables.
138

Návrh metodiky a vytvoření vybraných programových modulů pro nastavování a snímání defektů soustružnických nástrojů pomocí laserového měřícího zařízení / The design of methodology and creating of chosen SW modules for setting and exploring of lathe tools defects using laser measuring device

Křížek, Michal January 2008 (has links)
This diploma thesis deals with possibility of a non-contact tool corrections measurement and broken tool detection on CNC lathes. For this purpose was made a methodology for measuring and application in NC program. For testing the program in praxis was used CNC lathe SPM 16 with Sinumerik 840D controller. As measuring equipment was used a laser probe NC4 by Renishaw manufacturer.
139

Aktivismus a kolektivní násilí: Šluknovské nepokoje 2011 / Activism and Collective Violence: Šluknov Riots in 2011

Bizubová, Kateřina January 2016 (has links)
This thesis is focused on the issue of violence in civil society. Using Charles Tilly's political theory, it attempts to point out that the emergence of collective violence can be well understood by tracing small scale causes (mechanisms), rather than large causes (poverty, extremism etc.). This argument is empirically studied in the context of anti-Roma riots that took place in Šluknov Hook, Czech republic, in the year 2011. The research is based on a broad concept of civil society, which doesn't assume fixed division between civil and uncivil subjects, but works with a number of actors, whose identity is unstable and their acting strategy fluently changes from nonviolent to violent and contra. The data show, that radical actors are generally more prone to use force. However, Tilly's theory provides opportunity to explain their influence on majority through the dynamics of relationships that is studied in this paper. The catalogue of events was created on the basis of news and document analysis and the incidence of theoretically defined mechanisms is identified by process tracing method: Boundary activation between us and them (mainly network-based escalation, signaling spirals), polarization, competitive display, selective retaliation, containment, monitoring, certification/decertification and...
140

Décomposition de l'intéraction d'échange magnétique par l'approche à brisure de symétrie : théorie et applications / Decomposition of the magnetic exchange coupling in the broken-symmetry approach : theory and applications

David, Grégoire 16 November 2018 (has links)
Les travaux de recherche présentés dans cette thèse portent sur la méthode de décomposition de l'interaction d'échange ($J$) entre les centres magnétiques d'une molécule portant des électrons célibataires par l'approche à brisure de symétrie. Le but de cette méthode est d'extraire à l'aide des calculs non-restreints les différentes contributions physiques au couplage magnétique : l'échange direct ($J_0$) entre les orbitales magnétiques, l'échange cinétique ($\Delta J_{KE}$) permettant la délocalisation des orbitales magnétiques et la polarisation des orbitales de cœur ($\Delta J_{CP}$). La première partie de ce travail est consacrée à la théorie de la méthode de décomposition dans le cas le plus simple de deux électrons dans deux centres magnétiques d'un système centro-symétrique. La physique des contributions est expliquée en lien avec la présentation des outils méthodologiques et théoriques utilisés dans cette approche. La deuxième partie de cette thèse concerne l'implémentation de cette méthode dans le logiciel Orca et son application à des systèmes non-centrosymétriques. La dernière partie de ces travaux porte sur les développements méthodologiques que j'ai pu mener au cours de ces trois années de thèse. Une nouvelle approche permettant d'extraire la contribution de polarisation en spin est présentée. De plus, une proposition de généralisation de la décomposition de l'interaction d'échange magnétique basée sur la théorie des hamiltoniens effectifs est discutée. Un effort particulier a été porté sur l'explication et la signification physique de l'approche à brisure de symétrie dans le formalisme Hartree-Fock et la théorie de la fonctionnelle de la densité / This work is focused on the decomposition of the magnetic exchange coupling ($J$) between magnetic centers in the broken-symmetry approach. The purpose of this method is to extract from unrestricted calculations the different contributions to the magnetic coupling: the direct exchange ($J_0$) between the magnetic orbitals, the kinetic exchange interaction ($\Delta J_{KE}$) allowing the delocalization of the magnetic orbitals and the core polarization ($\Delta J_{CP}$) of non-magnetic electrons. The first part of this thesis is centered on the theory of the decomposition method in the simplest case of a centro-symmetric system with two electrons in two magnetic centers. The physical meaning is explained in relation with methodological and theoretical tools used in this approach. The second part presents the implementation of the method in the Orca package and its application to non centro-symmetric systems. In particular, this application highlights the interest of a such automatic method in standard quantum package. The last part of this work is focused on the methodological developments carried out during these three years. An innovative method avoiding the spin contamination problem is presented to extract the spin polarization effects. Furthermore, a generalization of the decomposition of $J$ to more complicated systems with more than two electrons in two magnetic centers is discussed. Special attention was given to the explanation and physical meaning of broken symmetry approach in Hartree-Fock and Density Functional Theory

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