Mässingslegeringar med låg blyhalt för svarvade komponenter ämnade för dricksvatten

This thesis is about brass alloys with low lead levels for manufacturing of turned components destined for human consumption. Is it technically possible, economically viable and environmentally necessary to produce lead-free brass alloys? Turning tests and leaching tests has been carried out in low-lead brass. The result of the tests carried out show that it is technically possible to produce faucets in low-leaded brass, but since these alloys are harder and less ductile, it takes more power and more cooling when it is processed. There should be more reality-based tests in regular machines that belong in the line of manufacturing. Tests is needed to find out which tool materials, cutting angles, cooling, etc. which are needed to manufacture products with the right surface, dimensions, durability, etc. One thing that no one knows today is the lifetime of a faucet made of low-lead brass. If these faucet’s do not have a higher life than that made in CW 602 N, it is a major strain on nature to produce these in low-lead brass, then to maintain production of the faucets as it is today. No information has come from the Boverket of tougher requirements for lead content in brass. This makes it difficult to know how much effort that is needed to replace lead. A legal requirement or to lose market areas is otherwise a good motivation to move forward.

Precificação de ativos sem cotação corrente de mercado na indústria de private equity e venture capital no Brasil

Neste trabalho são estudadas as características do mercado de private equity e venture capital no Brasil, particularmente no que se refere às metodologias de avaliação de investimentos, com o intuito de procurar identificar o método que se ajusta melhor à realidade brasileira para mensuração de ativos sem cotação corrente de mercado, presentes nas carteiras dos Fundos Mútuos de Investimento em Empresas Emergentes e Fundos de Investimento em Participações. Para atingir este objetivo, serão discutidos os principais mercados no exterior, ou seja, Estados Unidos e Europa, bem como as características específicas deste mercado no Brasil, além de apresentar como a Comissão de Valores Mobiliários trata o assunto, uma vez que os ativos aqui tratados não possuem marcação a mercado, como ocorre em outros fundos disciplinados por esta autarquia. Em seguida, são descritas as metodologias a partir das quais serão investigadas as formas como as organizações gestoras abordam os métodos em seus regulamentos e confrontadas as opiniões das organizações mencionadas com as dos investidores. Por fim, busca-se atingir o objetivo proposto utilizando o comportamento do valor das cotas no período de vida dos fundos como indicador do método mais apropriado.

Acesso aos serviços odontológicos e incidência de cárie em adolescentes e fatores de risco em município do Nordeste Brasileiro, 2006

The aims of this study were to analyze the access of dental services by child population, to determine the prevalence of dental caries, gingivitis and malocclusion in resident children from the municipal district of Sobral Ceará and to evaluate the incidence of the dental decay in adolescents associated with the factors related to socioeconomic condition, access to health services and self-perception. This study had as main factor the multidisciplinary represented by the participation of health professional (doctors, dentists, nurses) in the development of the survey's initial reference; student from Human Sciences area to apply the structured questionnaire in domiciliary visits; statistics professionals in the orientation of the analysis to be held and family health team (community health agents, dentists and dental clinic assistants) in the scheduling of domiciliary visits and the accomplishment of oral exam. The sample was determined from the domicile record that included children born between 1990 and 1994 to develop the research Children health conditions in the municipal district of Sobral Ceará . The first sample comprised 3425 parents of children from 5 to 9 years old, living in the urban area at the municipal district of Sobral Ceará, aiming at identifying the most important factors associated to the access to dental service. From this sample, 1021 children were selected in a systematic way, for the accomplishment to the epidemiological study of decay, gingivitis and malocclusion. In the study's third phase, in order to arrange the group to be followed, 688 adolescents were examined and interviewed, by means of the active search from the 1021 individuals that had been previously examined. It was observed that 50.9% of the children had access to dental service at least once in a lifetime. Of this total, 65.3% accomplished it during the last year, and 85.4% of these did in public services, what allows to identify the importance of this sector in the access to dental services. It was observed that the factors that most affected the access to dental 129 services were related to socioeconomic condition, such as the access to health plan, the possession of toothbrush, garbage collecting, mother s schooling, sewerage treatment and malnutrition. In relation to oral diseases, an increase in the DMF-T index according the age was observed, from 0.10 in five years old to 1.66 in the nine years old, while with the dmf-t index, the inverse happened, since the index decreased from 3.59 in five years old to 2.69 in nine years old. In relation to gingivitis, an average 32.7% of the children presented gum bleeding. In what concerns malocclusion, it was observed that 60.3% of the children didn't present any problem, 30.17% had light malocclusion and 9.5% severe malocclusion. The average incidence of dental caries was 1.86 teeth per youngster. Among the studied variables, tooth pain in the last six months, mother's income and school snack, adjusted by the perception about the need of treatment, the mother's schooling and the dentist's appointment at least once in a lifetime, were the variables that presented positive relationship with the high incidence of dental caries on this population by logistic regression. Variables of socioeconomic nature, related to the access to health services and behavior and biological variables presented a relationship with the high caries incidence. The study point out to the need of developing health actions in a humanized way, by an oral health team effectively bound to the population's interest, with the great objective to provide, with the public health services managers, adequate conditions to improve oral health

Protagonismo juvenil: uma avaliação do programa agente jovem de desenvolvimento humano na cidade de Natal RN (2006/2007).

This paper presents a critical rescue of the term youth, while simultaneously is presented as the lifetime of between 15 and 24 years. Rescue two features in the literature. The first considers youth as a transition period and the second phase work that from a predisposition to rebellion. Discusses the design plural of that term, youth recital to this social and historical aspects of different societies to which it relates and highlights the importance of realizing the diversity of it. Where the object of investigation, the Young Agent Program, the overall objective of the study is to evaluate the effectiveness of the actions of the Young Agent Program for Human Development in Natal-RN. Specifically aims to evaluate the effectiveness of the Young Agent Program: a) as an enhancer of the integration of young people in social spaces of family, school and community, b) as to (re) insertion and the incorporation of issues related to health in adolescence, and c ) regarding the work of young people as multipliers of the actions of the program. With regard to the methodological procedures presents a review of the literature on youth, and the categories of human development, leadership and evaluation of youth policies for the construction of theoretical and analytical approach, using documentary data collection in the Municipal Labor and Social Services - SEMT on the Young Agent Program, and interviews with actors involved in the program. Finally, evaluates the effectiveness of the Young Agent Program from the perspective of participants

Filosofar em tempos de informação

This thesis reflects upon the question of how does philosophy think a particular today, which is not only a legitimate philosophical task but a determinative characteristic of philosophy in general. Today's thought follows two paths: first, an hermeneutical-phenomenological analysis of Martin Heidegger's thought with regards to his own contemporaneity; and secondly, through the analysis of the contemporary phenomenon of Information Technology which in the present work is to be considered a privileged sign of our times and distinctive of the mindfulness of philosophy. Therefore, the starting point is an investigation of Heidegger's thinking on his own era to whom facticity is a way of accessing the fundamental question of philosophy. This thesis is led by three guiding words which hold onto a perspective of unity in Heidegger s lifetime of work: 1. Technicity, 2. History, 3. Language, to thereby develop a characterization of human existence as 1. Technopolitical, 2. Technoscientific, and 3. Technological. Finally, in keeping with this triangular characterization of the human, a philosophical comprehension of our times will be established and drawn by Information Technology illustrating three of its' factual signs that are understood to be the 'Remains of Being' today: The Emptying of Speech (Language); The Emptying of Science (History); The Emptying of The Object (Technicity). Through these nowadays phenomenon, it is possible to maintain a grip on the fundamental question, precisely when the task of philosophy seems to have peremptorily lost its meaning and come to its logical end and to show how philosophizing in the information era is as possible as it is necessary.

Propriedades ópticas de nanocristais de SiGe: efeitos de dopagem e desordem

We have used ab initio calculations to investigate the electronic structure of SiGe based nanocrystals (NC s). This work is divided in three parts. In the first one, we focus the excitonic properties of Si(core)/Ge(shell) and Ge(core)/Si(shell) nanocrystals. We also estimate the changes induced by the effect of strain the electronic structure. We show that Ge/Si (Si/Ge) NC s exhibits type II confinement in the conduction (valence) band. The estimated potential barriers for electrons and holes are 0.16 eV (0.34 eV) and 0.64 eV (0.62 eV) for Si/Ge (Ge/Si) NC s. In contradiction to the expected long recombination lifetimes in type II systems, we found that the recombination lifetime of Ge/Si NC s (τR = 13.39μs) is more than one order of magnitude faster than in Si/Ge NC s (τR = 191.84μs). In the second part, we investigate alloyed Si1−xGex NC s in which Ge atoms are randomly positioned. We show that the optical gaps and electron-hole binding energies decrease linearly with x, while the exciton exchange energy increases with x due to the increase of the spatial extent of the electron and hole wave functions. This also increases the electron-hole wave functions overlap, leading to recombination lifetimes that are very sensitive to the Ge content. Finally, we investigate the radiative transitions in Pand B-doped Si nanocrystals. Our NC sizes range between 1.4 and 1.8 nm of diameters. Using a three-levels model, we show that the radiative lifetimes and oscillator strengths of the transitions between the conduction and the impurity bands, as well as the transitions between the impurity and the valence bands are strongly affected by the impurity position. On the other hand, the direct conduction-to-valence band decay is practically unchanged due to the presence of the impurity

Comparação dos valores de desgaste abrasivo e de microdureza de 13 resinas compostas usadas em odontologia através do método do disco retificado

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Morphomettic changes on honeybee Apis mellifera L. workers fat body cells after juvenile hormone topic application at emergence

The effect of topical application of juvenile hormone (JH) over the lifetime of worker bees was evaluated in Apis mellifera, by measuring the area of the two cell types, trophocytes and oenocytes, found in the fat body. Topical application of 1 mu l of a 1 mu g/mu l solution of JH in acetone to the abdomens of newly emerged workers produced an increase in cell size, in both types of cell of 5-day-old treated workers in relation to the untreated control. The treatment was more effective on the oenocytes, since there were significant differences compared to the averages of the treatments and the interaction of the treatments with the age of the workers. The developmental pattern seemed to differ from the treated group. However, subsequent effects were probably dependent on different, natural variations in hormonal levels. (c) 2007 Elsevier Ltd. All rights reserved.

Search for neutral, long-lived particles decaying into two muons in p(p)over-bar collisions at root s=1.96 TeV

We present a search for a neutral particle, pair produced in pp collisions at root s=1.96 TeV, which decays into two muons and lives long enough to travel at least 5 cm before decaying. The analysis uses approximate to 380 pb(-1) of data recorded with the D0 detector. The background is estimated to be about one event. No candidates are observed, and limits are set on the pair-production cross section times branching fraction into dimuons + X for such particles. For a mass of 10 GeV and lifetime of 4x10(-11) s, we exclude values greater than 0.14 pb (95% C.L.). These results are used to limit the interpretation of NuTeV's excess of dimuon events.

Influência de nitrato de paládio, nitrato de magnésio e nitrato de níquel no comportamento térmico de arsênio em açúcares por espectrometria de absorção atômica em forno de grafite

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Plasmonic Coupling in Er3+:Au Tellurite Glass

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Visible and near-infrared luminescent Eu3+ or Er3+ doped laponite-derived xerogels and thick films: Structural and spectroscopic properties

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Utilização de um eletrodo de grafite-epóxi recoberto com [Zn(FEN)3][tetratris(4-clorofenil) borato]2 sensível a zinco(II) em meio 1,10-fenantrolina como eletrodo indicador em titulações potenciométricas de precipitação

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Local Er(III) environment in luminescent titanosilicates prepared from microporous precursors

The local environment of Er3+ ions in microporous titanosilicate ETS-10 and in synthetic narsarsukite and glassy materials obtained by calcination of ETS-10 has been investigated by EXAFS, Raman and photoluminescence spectroscopies. Er L-III-edge EXAFS studies of Er3+-doped ETS-10 support the view that the exchanged Er3+ ions reside close to the (negatively charged) TiO6 octahedra. In ETS-10, Er3+ is partially bonded to framework oxygen atoms and hydration water molecules. The Er...Ti distance (3.3 Angstrom) is similar to the Na...Ti distances (3.15-3.20 Angstrom) reported previously for Na-ETS-10. Although the exact location of the ErO6 units within the host structure of Er3+-doped synthetic narsarsukite is still an open question, it is most likely that Er3+ substitutes Ti4+ rather than Na+ ions. EXAFS spectroscopy indicates that no significant clustering of erbium atoms occurs in the titanosilicate samples studied. Evidence for the insertion of Er3+ ions in the framework of narsarsukite has been obtained by Raman spectroscopy. This is indicated by the increasing full-width at half-maximum (FWHM) of the 775 cm(-1) peak and the increasing intensity of the anatase peaks as the erbium content increases. In addition, as the narsarsukite Er3+ content increases a band at ca. 515 cm(-1) firstly broadens and subsequently a new peak appears at ca. 507 cm(-1).Er3+-doped narsarsukite exhibits a characteristic local vibrational frequency, (h) over bar omega ca. 330 cm(-1), with an electron-phonon coupling, g ca. 0.2, which constitutes additional evidence for framework Er3+ insertion. The number of lines in the infrared emission spectrum of synthetic narsarsukite indicates the presence of two optically-active erbium centres with very similar local environments and an average I-4(13/2) lifetime of 7.8 +/- 0.2 ms.

Strongly luminescent, highly ionic europium in a lanthanum diphenylphosphinate matrix

A series of insoluble, chemically inert and thermally stable compounds La1-xEux(DPP)3 (x = 0.50, 0.20, 0.10, and 0.050; DPP = diphenylphosphinate) was synthesized and characterized by elemental and thermogravimetric analysis, FT Infrared spectroscopy and X-ray powder diffraction. Luminescence spectroscopy at both 77 and 298 K showed changes in the intensity of the hypersensitive transition 5D 0 → 7F2 of Eu3+ which are dependent of the excitation wavelength, suggesting that the europium occupies two different sites in the compounds. The large quantum efficiency and quantum yield, as well as the long radiative lifetime of the 5D0 Eu3+ level of the series of compounds, which are desirable qualities for light-conversion molecular devices, are discussed in terms of the interactions and the energy transfer process between the ligands and the metal ion. © 2012 Elsevier B.V. All rights reserved.