998 resultados para Female fronted metal


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Solid-state M-2-MeO-Bz compounds, where M stands for bivalent Mn, Co, Ni, Cu and Zn and 2-MeO-Bz is 2-methoxybenzoate, have been synthesized. Simultaneous thermogravimetry-differential thermal analysis (TG-DTA), thermogravimetry, derivative thermogravimetry (TG/DTG), differential scanning calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results led to have information about the composition, dehydration, thermal stability and thermal decomposition of the isolated compounds.

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The hybrid 3-(1,4-phenylenediamine)propylsilica xerogel was obtained starting from two different organic precursor quantity (5 and 8 mmol) to 22 mmol of TEOS, in the synthesis. The xerogel samples were characterized by using CHN elemental analysis, N2 adsorption-desorption isotherms, infrared thermal analysis. The xerogel was used as metal sorbent for Cu2+, Cd2+ and Pb2+ in aqueous solution with concentration range of 10-3 to 10-5 mmol l-1. The quantity of organic precursor added in the synthesis influences the characteristics of the xerogel as morphology and thermal stability, as well as the metal adsorption capacity.

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The thermal decomposition behavior of the Fe(II), Co(II), Ni(II) and Zn(II) complexes of polydithiooxamide has been investigated by thermogravimetric analysis (TGA) at a heating rate of 20°C min-1 under nitrogen. The Coats-Redfern integral method is used to evaluate the kinetic parameters for the successive steps in the decomposition sequence observed in the TGA curves. The processes of thermal decomposition taking place in the four complexes are studied comparatively as the TGA curves indicate the difference in the thermal decomposition behavior of these complexes. The thermal stabilities of these complexes are discussed in terms of repulsion among electron pairs in the valence shell of the central ion and electronegativity effects.

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The Co(II), Ni(II) and Cu(II) metal ions complexes of Bis(4-amino-5-mercapto-1,2,4-triazol-3-yl) alkanes (BATs) have been prepared and characterized by elemental analysis, conductivity measurements infrared, magnetic susceptibility, the electronic spectral data and thermal studies. Based on spectral and magnetic results, the ligands are tetradentate coordinating through the N and S-atoms of BATs; six-coordinated octahedral or distorted octahedral and some times four-coordinated square planar were proposed for these complexes. Activation energies computed for the thermal decomposition steps were compared. The ligands and their metal complexes were tested in vitro for their biological effects. Their activities against two gram-positive, two gram-negative bacteria and two fungal species were found to vary from moderate to very strong.

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Solid state M-L compounds, were M stands for bivalent Mn, Fe, Co, Ni, Cu, Zn and L is pyruvate, have been synthesized. Thermogravimetry and derivative thermogravimetry (TG/DTG), differential scanning calorimetry (DSC), X-Ray powder diffractometry, infrared spectroscopy, elemental analysis, and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results led to information about the composition, dehydration, ligand denticity, and thermal decomposition of the isolated compounds.

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Divalent metal complexes of ligand 2-methoxybenzylidenepyruvate with Fe, Co, Ni, Cu and Zn as well as sodium salt were synthesized and investigated in the solid state. TG curves of these compounds were obtained with masses sample of 1 and 5mg under nitrogen atmosphere. Different heating rates were used to characterize and study these compounds from the kinetic point of view. The activation energy and pre-exponential factor were obtained applying the Wall-Flynn-Ozawa method to the TG curves. The obtained data were evaluated and the values of activation energy (Ea / kJ mol-1) was plotted in function of the conversion degree (α). The results show that due to mass sample, different activation energies were obtained. The results are discussed mainly taking into account the linear dependence between the activation energy and the pre exponential factor, where was verified the effect of kinetic compensation (KCE) and possible linear relations between the dehydrations steps of these compounds.

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Solid State M-2-MeO-CP compounds, where M stands for bivalent metals (Mn, Fe, Co, Ni, Cu and Zn) and 2-MeO-CP is 2-methoxycinnamylidenepyruvate, were synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), elemental analysis and complexometry were used to establish the stoichiometry and to study the thermal behaviour of these compounds in CO2 and N2 atmospheres. The results were consistent with the general formula: M(L)2∙H2O. In both atmospheres (CO2, N2) the thermal decomposition occurs in consecutive steps which are characteristic of each compound. For CO2 atmosphere the final residues were: Mn3O4, Fe3O4, Co3O4, NiO, Cu2O and ZnO, while under N2 atmosphere the thermal decomposition is still observed at 1000 º C.

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Thermal stability and thermal decomposition of succinic acid, sodium succinate and its compounds with Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) were investigated employing simultaneous thermogravimetry and differential thermal analysis (TG-DTA) in nitrogen and carbon dioxide atmospheres and TG-FTIR in nitrogen atmosphere. On heating, in both atmospheres the succinic acid melt and evaporate, while for the sodium succinate the thermal decomposition occurs with the formation of sodium carbonate. For the transition metal succinates the final residue up to 1180 ºC in N2 atmosphere was a mixture of metal and metal oxide in no simple stoichiometric relation, except for Zn compound, where the residue was a small quantity of carbonaceous residue. For the CO2 atmosphere the final residue up to 980 ºC was: MnO, Fe3O4, CoO, ZnO and mixtures of Ni, NiO and Cu, Cu2O.

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Female sexual dysfunctions, including desire, arousal, orgasm and pain problems, have been shown to be highly prevalent among women around the world. The etiology of these dysfunctions is unclear but associations with health, age, psychological problems, and relationship factors have been identified. Genetic effects explain individual variation in orgasm function to some extent but until now quantitative behavior genetic analyses have not been applied to other sexual functions. In addition, behavior genetics can be applied to exploring the cause of any observed comorbidity between the dysfunctions. Discovering more about the etiology of the dysfunctions may further improve the classification systems which are currently under intense debate. The aims of the present thesis were to evaluate the psychometric properties of a Finnish-language version of a commonly used questionnaire for measuring female sexual function, the Female Sexual Function Index (FSFI), in order to investigate prevalence, comorbidity, and classification, and to explore the balance of genetic and environmental factors in the etiology as well as the associations of a number of biopsychosocial factors with female sexual functions. Female sexual functions were studied through survey methods in a population based sample of Finnish twins and their female siblings. There were two waves of data collection. The first data collection targeted 5,000 female twins aged 33–43 years and the second 7,680 female twins aged 18–33 and their over 18–year-old female siblings (n = 3,983). There was no overlap between the data collections. The combined overall response rate for both data collections was 53% (n = 8,868), with a better response rate in the second (57%) compared to the first (45%). In order to measure female sexual function, the FSFI was used. It includes 19 items which measure female sexual function during the previous four weeks in six subdomains; desire, subjective arousal, lubrication, orgasm, sexual satisfaction, and pain. In line with earlier research in clinical populations, a six factor solution of the Finnish-language version of the FSFI received supported. The internal consistencies of the scales were good to excellent. Some questions about how to avoid overestimating the prevalence of extreme dysfunctions due to women being allocated the score of zero if they had had no sexual activity during the preceding four weeks were raised. The prevalence of female sexual dysfunctions per se ranged from 11% for lubrication dysfunction to 55% for desire dysfunction. The prevalence rates for sexual dysfunction with concomitant sexual distress, in other words, sexual disorders were notably lower ranging from 7% for lubrication disorder to 23% for desire disorder. The comorbidity between the dysfunctions was substantial most notably between arousal and lubrication dysfunction even if these two dysfunctions showed distinct patterns of associations with the other dysfunctions. Genetic influences on individual variation in the six subdomains of FSFI were modest but significant ranging from 3–11% for additive genetic effects and 5–18% for nonadditive genetic effects. The rest of the variation in sexual functions was explained by nonshared environmental influences. A correlated factor model, including additive and nonadditive genetic effects and nonshared environmental effects had the best fit. All in all, every correlation between the genetic factors was significant except between lubrication and pain. All correlations between the nonshared environment factors were significant showing that there is a substantial overlap in genetic and nonshared environmental influences between the dysfunctions. In general, psychological problems, poor satisfaction with the relationship, sexual distress, and poor partner compatibility were associated with more sexual dysfunctions. Age was confounded with relationship length but had over and above relationship length a negative effect on desire and sexual satisfaction and a positive effect on orgasm and pain functions. Alcohol consumption in general was associated with better desire, arousal, lubrication, and orgasm function. Women pregnant with their first child had fewer pain problems than nulliparous nonpregnant women. Multiparous pregnant women had more orgasm problems compared to multiparous nonpregnant women. Having children was associated with less orgasm and pain problems. The conclusions were that desire, subjective arousal, lubrication, orgasm, sexual satisfaction, and pain are separate entities that have distinct associations with a number of different biopsychosocial factors. However, there is also considerable comorbidity between the dysfunctions which are explained by overlap in additive genetic, nonadditive genetic and nonshared environmental influences. Sexual dysfunctions are highly prevalent and are not always associated with sexual distress and this relationship might be moderated by a good relationship and compatibility with partner. Regarding classification, the results supports separate diagnoses for subjective arousal and genital arousal as well as the inclusion of pain under sexual dysfunctions.

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Den rikt utformade och komplexa hinduiska traditionen har hittills huvudsakligen tecknats av manliga forskare och det är främst manliga religiösa strävanden som har dokumenterats. Detta förhållande och de patriarkala synsätt som styr många auktoritativa heliga texter har bidragit till att skapa intrycket att hinduiska kvinnors religiösa erfarenheter antingen saknas eller är avsevärt begränsade. Denna studie lyfter fram det faktum att ett ökande antal indiska kvinnor inom dagens hinduism axlar publika roller som religiösa ledare. Med sitt framträdande utmanar många av dessa rådande sociala uppfattningar om kvinnors underordnade ställning och främjar därmed en förnyad medvetenhet av urgamla föreställningar om Gud som kvinna. Avhandlingen utforskar fenomenet kvinnliga guruer genom att belysa sjuttio guruers andliga karriär, med särskild fokus på fyra av dem. Några av de frågor som behandlas är följande: På vilket sätt är kvinnliga guruer del av den hinduiska traditionen? Vilka förväntningar ställs på dem? Hur legitimeras deras auktoritet som guruer? Hur handskas guruerna med sina dubbla roller som kvinnor och andliga ledare? Hur återspeglas gudinnans ställning, som i indisk religiositet ofta är central, i kvinnors faktiska verklighet? Bidrar kvinnliga guruer med sitt religiösa engagemang till att nyskapa och förändra den indiska religiösa diskursen och utövningen av religion?

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Populärkulturen har i dagens läge kommit att utgöra en allt mer viktig och central inspirationskälla för allt fler människors konstruktion av den egna religiösa identiteten även inom traditionella och institutionella kristna sammanhang. Denna avhandling belyser denna utveckling i ljuset av den finländska kristna metallmusik-kulturen - en sällsynt stark sammanblanding av protestantisk kristendom och en utpräglad och kontroversiell populärmusikform och dess kultur. Fokus riktas framför allt på hur den kristna metallmusik-kulturen blir meningsfull för sina medlemmar genom de sätt på vilka den konstrueras diskursivt, dvs. genom de sätt på vilka den representeras och talas om bland sina egna anhängare. Den diskursiva konstruktionen av den kristna metallmusik-kulturen utforskas på ett såväl bredare transnationellt som ett finländskt nationellt plan. Studien redogör även för den kristna metalmusikens och -kulturens huvudsakliga verbala, visuella och estetiska kännetecken. Uppbyggnaden och spridningen av dagens transnationella kristna metallmusik-kultur undersöks även i ljuset av det teoretiska konceptet scene. Avhandlingens centrala argument är att den kristna metallmusikscenen erbjuder sina medlemmar en mängd resurser för skapandet av ett alternativt och komplementärt religiöst uttrycksätt, religiös praxis och en alternativ kristen identitet.

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Kirja-arvio

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In this study we discuss the atomic level phenomena on transition metal surfaces. Transition metals are widely used as catalysts in industry. Therefore, reactions occuring on transition metal surfaces have large industrial intrest. This study addresses problems in very small size and time scales, which is an important part in the overall understanding of these phenomena. The publications of this study can be roughly divided into two categories: The adsorption of an O2 molecule to a surface, and surface structures of preadsorbed atoms. These two categories complement each other, because in the realistic case there are always some preadsorbed atoms at the catalytically active surfaces. However, all transition metals have an active d-band, and this study is also a study of the in uence of the active d-band on other atoms. At the rst part of this study we discuss the adsorption and dissociation of an O2 molecule on a clean stepped palladium surface and a smooth palladium surface precovered with sulphur and oxygen atoms. We show how the reactivity of the surface against the oxygen molecule varies due to the geometry of the surface and preadsorbed atoms. We also show how the molecular orbitals of the oxygen molecule evolve when it approaches the di erent sites on the surface. In the second part we discuss the surface structures of transition metal surfaces. We study the structures that are intresting on account of the Rashba e ect and charge density waves. We also study the adsorption of suphur on a gold surface, and surface structures of it. In this study we use ab-initio based density functional theory methods to simulate the results. We also compare the results of our methods to the results obtained with the Low-Energy-Electron-Difraction method.

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A pesquisa aborda a reciclagem do composto de lixo urbano (CLU) como fertilizante alternativo na cana-de-açúcar e como solução social e ambiental ao acúmulo de resíduos sólidos nos centros urbanos. Utilizou-se da modelagem matemática para conhecer a dinâmica dos metais pesados, visando ao estabelecimento de critérios e procedimentos para o uso seguro do CLU, limitado pela quantidade desses elementos. Foram construídos modelos compartimentais a partir de dados de experimentos em condições controladas e parcialmente validados com dados de campo. Esse modelo descreveu a transferência de metais pesados no sistema solo-raiz-parte aérea para a cana-de-açúcar. Pôde-se concluir, pelas condições desta pesquisa, que o metal mais preocupante foi o níquel, pois demora, aproximadamente, três anos para ser atenuado no solo e chega em maior quantidade na parte aérea. Quanto aos fatores argila, óxidos e pH do solo, notou-se que, nos solos de maior poder tampão, a passagem da maioria dos metais foi mais lenta. Esse modelo pode tornar-se importante aliado na definição de leis de utilização do CLU, visando à não-contaminação ambiental, redução no acúmulo de lixo e de custos de produção.