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The present study aimed to investigate the predictors of conduct problems and callous-unemotional (CU) traits in a non-clinic sample of children from different socioeconomic levels. It was hypothesized that conduct problems and CU traits will be associated with different risk factors. Regression analyses were conducted in order to find out the predictors of conduct problems/hyperactivity and CU traits. Results showed some significant differences between risk factors of conduct problems/hyperactivity and CU traits. Predictors according to mothers&rsquo / and teachers&rsquo / ratings were not the same, except for some overlapping variables. The findings indicated that teachers could not differentiate conduct problems/hyperactivity symptoms and CU traits appropriately from each other. However, they could make more reliable comparisons between two groups of children with conduct problems who differ on severity of CU levels as compared to mothers. The results were discussed in terms of using of multiple informants forassessing different problem areas in children. In addition, the study aimed to investigate the differences between three groups of children, namely, children with conduct problems and high CU traits, children with conduct problems and low CU traits, and children without conduct problems and low CU traits were compared on child-related, parenting-related, and other family measures by using multiple factorial analyses of variances. Although significant differences were found between the control group and the two conduct group, the significant differences between the two conduct groups were limited. The results were discussed in terms of treatment needs and possible differences in cultural expression of CU traits.

The Au-Al bond is a commonly used interconection in IC package.The different composition for Au wire will change the different IMC growth. In this study, we will discuss the pure Au wire, and little Pd or Cu addition in Au wire reacted with Al pad for thermal aging, and we will give the models for these cases.

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Die Kenntnisse über die zur Passivierung führenden Wechselwirkungen des Verunreinigungselements Cu mit EL2 und EL6 wurden dahingehend erweitert, dass ein Gültigkeitsbereich für die Messungen zur Bestimmung der konzentrationsproportionalen Messgröße der Defekte festgelegt wurde. Der Defekt EL6 ist das die 0.8 eV-PL-Emission bedingende und die Ladungsträgerlebensdauer determinierende Rekombinationszentrum. Die Lebensdauer wird durch mindestens ein weiteres Zentrum beeinflusst. Die atomare Struktur des EL6 wurde mit AsGa VAs und die des weiteren Zentrums mit Asi bestimmt. Mittels Wärmebehandlung kann die Ladungsträgerlebensdauer gezielt beeinflusst werden. Bei der Bildung und Annihilation sowie der Verteilung der Defekte EL2, EL6, VGa und der As-Ausscheidungen besteht eine wechselseitige Korrelation. Sowohl strukturelle Defekte als auch die Inkorporation von Dotierelementen, deren Atomradien deutlich kleiner sind als Ga und As, stellen beeinflussende Faktoren dar. Das Defekt-Transformations-Modell erklärt die Bildung wachstumsfähiger Keime einer As-Ausscheidung durch EL2 bzw. EL6 mit den sich in der ersten Koordingationssphäre befindenden As-Atomen. Das Gitterrelaxations-Modell ermöglicht die Interpretation der katalytischen Wirkung des Dotierelements C. Die Umsetzung dieser Ergebnisse bedeutet die Anwendung des Defect Engineerings im SI-LEC-GaAs.

<p>Humans are exposed to metals and metal-containing materials daily, either conscious, e.g. using metal tools or objects, or unconscious, e.g. during exposure to airborne metal-, and metal-containing particles. The diffuse dispersion of metals from different sources in the society, and the concern related to its potential risk for adverse effects on humans have gained an increased public and governmental attention both on a national and international level. In this context, the knowledge on metal release from metallic objects or metal-containing particles is essential for health risk assessment.</p><p>This thesis focuses on the study of metal release from powder particles of stainless steel and Cu-based materials exposed to synthetic body fluids mainly for simulating lung-like environments. The study comprises: i) development of a suitable experimental method for metal release studies of micron sized particles, ii) metal release data of individual alloy constituents from stainless steel powder particles of different particle sizes, and iii) Cu release from different Cu-based powder particles. In addition, the influence of chemical and physical properties of metallic particles and the test media are investigated. Selected results from Ni powder particles exposed to artificial sweat are presented for comparison. The outcome of this research is summarized through ten questions that are formulated to improve the general understanding of corrosion-induced metal release from metallic particles from a health risk perspective.</p><p>A robust, reproducible, fairly simple, and straightforward experimental procedure was elaborated for metal release studies on particles of micron or submicron size. Results in terms of metal release rates show, for stainless steel powder particles, generally very low metal release rates due to a protective surface oxide film, and Fe preferentially released compared to Cr and Ni. Metal release rates are time-dependent for both stainless steel powder particles and the different Cu-containing powders investigated. The release of Cu from the Cu-containing particles depends on the chemical and compositional properties of the Cu-based material, being either corrosion-induced or chemically dissolved. Moreover, the test medium also influences the metal release process. The metal release rate increases generally with decreasing pH of the test media. However, even at a comparable pH, the release rate may be different due to differences in the interaction between the particle surface and specific media.</p><p>The nature of particles is essentially different compared to massive sheet in terms of physical shape, surface composition and morphology. The surface area, and even the surface composition of metallic particles, depend on the particle size. The specific surface area of particles, area per mass, is intimately related to the particle size and has a large effect on the metal release process. Release rates increase with decreasing particle size due to a larger active surface area that takes part in the corrosion/dissolution process. The surface area that actually is active in the corrosion and metal release process (the effective area) governs the metal release process for both particles and massive sheet of metals or alloys. For particles, the effective surface area depends also on agglomeration conditions of particles during exposure.</p>

According to the scientific research schoolchildren lack knowledge of healthy way of life and physical education. Most researchers claim that students health is getting worse and physical inactivity, smoking. Irrational nutrition has been spreading. However, school physical education research is mostly based on the development of schoolchildren physical abilities of various body systems. Thees the experiment was carried out to investigate the incorporation of theoretical lessons on physical education and healthy way of life into the process of physical training by using using different activating methods. Research objective: To investigate the efficiency of activating teachings methods and their effect on the physical activity and acquistition of the knowledge oh healthy way of life among 7 -8 fom students in a basic school. 386 schoolchildren participated in the pedagogical experiment conducted in Vilnius „Emilijos Pliaterytės” basic school from September 2004 till March 2005. Research methods used in a Masters thesis were as follows: analysis of literature, questionnaire methods, pedagogical experiment, mathematical, statistical analysis. The change in the knowledge of the healthy way of life and physical educations was determined by a questionnaire method during the period of experiment. Activating methods (discussions, debates, brainstorming, each student active invillvement) were used in experimental gruops to extend and improve students knowledgw of healthy... [to full text]

La modélisation des efforts de coupe en usinage est nécessaire pour prédire certaines caractéristiques de la pièce usinée comme sa géométrie, son état de surface ou encore l'intégrité de la matière en sub-surface.Les nombreux modèles d'efforts de coupe déjà développés sont souvent appliqués dans le cas d'opérations d'usinage simples, ce qui limite leur diffusion vers le milieu industriel, alors qu'il existe un réel besoin de modélisation d'opérations d'usinage complexes et variées, et prenant en compte d'éventuels changements métallurgiques au niveau du matériau usiné.L'objectif de ces travaux est de proposer un modèle d'efforts de coupe appliqué à toute opération de tournage d'une part et considérant certaines propriétés mécaniques du matériau usiné d'autre part.Concernant l'aspect multi-opérations, un modèle géométrique utilisant des transformations homogènes a été développé et permet de décrire à la fois la trajectoire et la géométrie de l'outil. Les effets de paramètres originaux, tels que le diamètre de la pièce, l'angle de direction d'arête et le rayon de bec, sont étudiés, notamment à l'aide de nouvelles configurations de coupe élémentaires. La prise en compte de ces paramètres dans les relations de coupe locales permet finalement d'améliorer la simulation des efforts de coupe lors d'un contournage.L'approche utilisée pour l'aspect multi-matériaux consiste à modifier progressivement le matériau usiné. Ainsi, le matériau initial, le cuivre pur, a été étudié dans différents états métallurgiques, obtenus par des traitements thermo-mécaniques. En particulier, le procédé d'extrusion coudée à aires égales (ECAE) a été utilisé afin d'écrouir le matériau dans la masse. Ainsi, trois matériaux aux caractéristiques mécaniques différentes mais conservant plusieurs caractéristiques communes (thermiques notamment) ont pu être comparés en termes d'efforts de coupe. Les coefficients des relations de coupe sont finalement mis en regard des propriétés mécaniques obtenues par des essais de traction et de compression à grande vitesse.

The Marathon PGM-Cu deposit is hosted by the Coldwell alkaline complex, which consists predominantly of gabbro and syenite and was emplaced at 1108 Ma as part of the Mid-Continent Rift System. Mineralization at the Marathon PGM-Cu deposit is hosted by the Two Duck Lake Gabbro (TDLG), a fresh olivine-bearing gabbro. The Marathon deposit contains several zones of mineralization including the Basal Zone, the Main Zone and the W-Horizon. The W-Horizon is a high-grade PGE zone characterized by low S, low Cu/Pd and high Cu/Ni. The sulphide mineral assemblage is predominantly chalcopyrite and bornite. This contrasts with the Main Zone where the dominant sulphide mineral assemblage is chalcopyrite and pyrrhotite. The Main Zone contains higher S, higher Cu/Pd and shows a decrease in Cu/Pd and pyrrhotite/chalcopyrite from base to top. Four drill holes were selected for detailed analysis to characterize the W-Horizon style of mineralization. Detailed petrographic study of the pristine and largely unaltered TDLG shows that wide spread hydrothermal alteration is not responsible for the mineralization. Detailed outcrop mapping shows that the TDLG intruded as a series of multiple intrusions in a dynamic magmatic system. Geochemical studies through the W-Horizon show that the mineralization is not the result of crystallization in a layered intrusion. The results of geochemical assays and electron microprobe analysis of olivine grains show that the chemistry through the TDLG hosting the W-Horizon is erratic. This data supports the TDLG intruding as a series of sills in a dynamic conduit environment. The calculated sulphide metal tenors for the W-Horizon are higher than can be explained by closed system R Factor models. Multistage dissolution upgrading in an open system is examined as the process forming the W-Horizon. This model is able to produce the sulphide metal tenors observed in the W-Horizon. Sulphur loss also affects grades and tenors and was examined through geochemical and petrological data. The change in sulphide mineral assemblage from a pyrrhotite and chalcopyrite (S-rich) to chalcopyrite and bornite (S-poor) supports S-loss. Whole rock S and Se contents are also analyzed to investigate S loss, a lower S/Se indicates that sulphur has been removed from the system. Average S/Se values are ~800 for the W-Horizon, ~1980 for the Main Zone and ~1700 in unmineralized samples. The very low S/Se observed within the W-Horizon supports S-loss. Sulphur loss in a dynamic magmatic conduit system is proposed for the formation of the W-Horizon mineralization. In this model sulphur undersaturated basaltic magma interacted with an immiscible sulphide liquid in a magma conduit, resulting in the dissolution of sulphide into the basaltic melt and PGE enrichment.

Made available in DSpace on 2016-06-02T19:56:55Z (GMT). No. of bitstreams: 1 DissJEF.pdf: 1826030 bytes, checksum: a3043074648b14bbec76bd05d3190200 (MD5) Previous issue date: 2005-03-04 / Universidade Federal de Sao Carlos / The minimization of the emissions of nitrogen oxides (NOx) in the atmosphere has been one of the great goals in the area of environmental protection. Among the possible processes to treat the NOx, the selective catalytic reduction of NO with hydrocarbons (SCR-HC) has presented important expectations. For this process, the metal/ZSM-5 type catalysts have appropriate levels of conversion in oxidative conditions. In this context, the aim of this work was to prepare Cu, Co and FeZSM-5 catalysts. The samples were characterized by XRD, DRS-UVVIS, FTIR, H2-TPR, SEM and tested in the reduction of NO to N2 with propane or methane in oxidative atmosphere in the presence or absence of water steam. The H2-TPR data showed that the cationic species present in the prepared Cu, Co and FeZSM-5 catalysts, after thermal activation, were mainly Cu2+ (Cu&#945; 2+ e Cu&#946; 2+), Co2+ and Fe3+ cations located in charge compensation sites in the zeolite, respectively. From FTIR and DRS-UVVIS it was also possible identify oxide species, which were present in a lower content. In the reduction of NO to N2 in the absence of water steam, the CuZSM-5 catalysts showed higher levels of conversion of NO than those based in Co and Fe. However, the FeZSM-5 catalysts showed, in this condition, activity at lower temperatures. This behavior makes them potentially interesting to be applied for practical purposes. On the other hand, in the presence of water steam, it was verified a higher loss of activity of the CuZSM-5 catalyst, which was totally restored removing the water in the feed. For the Co and FeZSM-5 catalysts, the activity loss in the presence of water steam was partially recovered during time on stream. / A minimização das emissões de óxidos de nitrogênio (NOx) na atmosfera tem sido um dos grandes desafios da área de proteção ambiental. Dentre os processos para o tratamento dos NOx possíveis, a redução catalítica seletiva do NO com hidrocarbonetos (RCS-HC) vem apresentando excelentes perspectivas. Para este processo os catalisadores metal/zeólita ZSM-5 possuem adequados níveis de conversão em condições oxidantes. Dentro deste contexto, este trabalho teve como objetivo preparar catalisadores Cu, Co e FeZSM-5. As amostras foram caracterizadas por DRX, DRS-UVVIS, FTIR, RTP-H2, MEV e sua atividade verificada através da redução de NO a N2 com propano ou metano em atmosfera oxidante, na presença ou ausência de vapor de água. Os resultados de RTP-H2 mostraram que as espécies presentes nos catalisadores Cu, Co e FeZSM-5, após ativação térmica, foram principalmente os cátions Cu2+ (Cu&#945; 2+ e Cu&#946; 2+), Co2+ e Fe3+ compensando carga na zeólita, respectivamente. A partir de FTIR e DRS-UVVIS foi possível, também, identificar espécies oxidas, as quais estavam presentes em teores menores. Na redução de NO a N2 na ausência de vapor de água os catalisadores CuZSM-5 apresentaram maiores conversões de NO que os contendo Fe ou Co. Entretanto, os catalisadores FeZSM-5 apresentaram, nessa condição, atividade em temperaturas menores, o que mostra uma vantagem para o seu uso prático. Na presença de vapor de água, verificou-se uma maior queda da atividade no catalisador CuZSM-5, somente recuperada com a retirada desse composto na alimentação, sendo que para os catalisadores CoZSM-5 e FeZSM-5 a perda de atividade foi parcialmente recuperada ao longo do tempo.