Simulação da qualidade da água em regime não-permanente no rio dos Sinos, RS

A bacia do rio dos Sinos ocupa uma área de 3 700 km² e situa-se em uma área de grande concentração urbana e industrial próxima à região metropolitana de Porto Alegre. O rio dos Sinos tem sua foz no delta do Jacuí e se apresenta bastante poluído no seu trecho final. Este estudo buscou ampliar as características do modelo de qualidade da água em regime não-permanente desenvolvido por Tucci (1978) para simular outros parâmetros de qualidade e utilizá-lo como ferramenta de análise das condições do rio dos Sinos. O modelo em estudo pode ser dividido em dois módulos: hidráulico e de transporte de massa. O modelo foi aplicado no trecho final do Rio dos Sinos compreendido entre o posto fluviométrico de Campo Bom e a foz do rio. Este trecho foi divido em 21 seções transversais nas quais foram avaliadas as condições hidráulicas e ambientais. A simulação do trecho em estudo em regime não-permanente reveste-se de importância na medida em que leva em consideração a inversão de fluxo a que o rio está sujeito nos períodos de estiagem. Os resultados obtidos demonstraram a variação diária das condições hidráulicas e ambientais que se verificam de forma mais intensa nas seções situadas próximas a foz do Rio dos Sinos como conseqüência da inversão de fluxo. Além disso, buscou-se avaliar as condições ambientais associadas a uma condição de estiagem crítica e o nível de tratamento dos efluentes necessário para manter a qualidade da água dentro dos padrões determinados pela resolução 20/86 do CONAMA.The Sinos River Basin has a surface of 3,700 km ² and is located in a very important urban and industrial region next to the Porto Alegre metropolitan area. The Sinos River has its mouth on the Delta of Jacuí and become very polluted as it gets closer to the end. The purpose of this work is to enlarge the features of the water quality model developed by Tucci (1978) to simulate another water quality parameters and to make use of it as a tool to evaluate Sinos' River conditions. The model studied here can be divided in two modules: a hydraulic anda mass transport one. The mathematical model was applied in the final course of the Sinos' River which is delimited between Campo Bom fluviometric station and the mouth of the river. This course was divided in 21 transverrsal sections where we evaluate hidraulic and ambiental conditions. The simulation of this course in non-permanent state becomes very important as we consider the downstream effects that the river undergoes during dry periods. The results that we obtain make clear that the daily variations of hidraulic and ambiental conditions are more intensive as we get closer to the end of the river. Besides that we also evaluate ambiental conditions associated with a dry period and the wastes reduction that are necessary to bring this conditions in accordance with the local legislation

Definição do coeficiente de difusão para propagação de poluentes em águas rasas empregando um modelo baseado em soluções exatas para a equação de Korteweg-De-Vries

Pollutant dispersion in rivers occurs as a consequence of diffusion and advection both transversal and longitudinal dretions of the flow. The contribution related to the diffusion process, ruled by Fick´s law, is proportional to diffusion coefficient, which must be estimated. In this work a new analytical solution to the Korteweg-de-Vries equation is obtained, in order to evaluate the increase in the mass diffusivity due to the action of gravity waves along water bodies. The proposed method consists in mapping the original KdV equation into an ordinary differential one whose solution is obtained by integration. When a soliton or a wave packet is produced on the surface, a certain amount of water is transferred from the neighborhoods, carrying the pollutants by means of advection transport. However, since the oscillations are alternant along the water body, and the typical wavelength of the packets is much smaller than the distance between margins, this advection process can be regarded as an isotropic diffusion mechanism, when observed at a geographic scale. Hence, the mass diffusivity due to the gravity waves can be estimated from the local values for the laplacian and the time derivative of the concentration distribution, obtained through a mass balance in a region around the soliton. Numerical solutions are presented.A dispersão de poluentes no meio aquático decorre dos processos de advecção e difusão, cuja propagação se produz no sentido longitudinal e transversal ao escoamento do corpo hídrico. A contribuição associada ao processo difusivo, regido pela lei de Fick, é proporcional ao coeficiente de difusão, cujo valor deve ser estimado. Neste trabalho é obtida uma solução analítica para a equação de Korteweg-de-Vries (KdV) a fim de avaliar o coeficiente de difusão baseado na ação de ondas de gravidade em corpos hídricos. O método proposto consiste na transformação da equação KdV em sua forma original em uma equação diferencial ordinária cuja solução é obtida através de integração. Quando uma onda solitária ou um trem de ondas é produzido na superfície de um rio, uma determinada quantidade de água é transferida a partir das vizinhanças, transportando poluentes por advecção. Contudo, uma vez que as oscilações são alternantes ao longo do corpo hídrico, e o comprimento de onda típico das vagas é muito inferior à distância entre margens, esse processo de advecção pode ser considerado um mecanismo de difusão isotrópica, quando observado em escala geográfica. Desse modo, a difusividade mássica pode ser estimada a partir de valores locais para o laplaciano e a derivada temporal da concentração, obtidos através de um balanço de massa efetuado em torno da onda solitária. Ao final, são apresentados resultados numéricos para a situação do Lago Guaíba, em Porto Alegre

Experimento didático de baixo custo para determinação do perfil de temperatura de uma aleta exposta ao ar ambiente

O artigo descreve um experimento didático de baixo custo, no qual as temperaturas numa aleta, exposta ao ambiente, convecção natural e regime permanente, são registradas com câmera termográfica. Para a realização dos ensaios, foi confeccionado um equipamento constituído por uma caixa de isopor e uma haste cilíndrica de alumínio, pintada de preto, engastada nessa caixa. A porção inserida na caixa ficou imersa em um banho de água com temperatura controlada, e o perfil de temperatura na porção exposta ao ar foi determinado. Os dados experimentais foram confrontados com valores previstos, no modelo teórico tradicional, que considera apenas a transferência convectiva de calor na superfície da aleta e, com um modelo modificado, no qual também é computada a transferência radiante de calor nessa superfície. Os resultados obtidos indicam a necessidade de considerar a transferência de calor por radiação e a adequabilidade da metodologia proposta na determinação do perfil de temperatura em aletas e do emprego do experimento para fins didáticos

A low-cost didactic module for temperature profile determination of a fin exposed to ambient air

O artigo descreve um experimento didático de baixo custo, no qual as temperaturas numa aleta, exposta ao ambiente, convecção natural e regime permanente, são registradas com câmera termográfica. Para a realização dos ensaios, foi confeccionado um equipamento constituído por uma caixa de isopor e uma haste cilíndrica de alumínio, pintada de preto, engastada nessa caixa. A porção inserida na caixa ficou imersa em um banho de água com temperatura controlada, e o perfil de temperatura na porção exposta ao ar foi determinado. Os dados experimentais foram confrontados com valores previstos, no modelo teórico tradicional, que considera apenas a transferência convectiva de calor na superfície da aleta e, com um modelo modificado, no qual também é computada a transferência radiante de calor nessa superfície. Os resultados obtidos indicam a necessidade de considerar a transferência de calor por radiação e a adequabilidade da metodologia proposta na determinação do perfil de temperatura em aletas e do emprego do experimento para fins didáticos.The article describes a low-cost didactic experiment, in which the temperatures in a fin, exposed to ambient, natural convection and steady-state, are recorded with a thermographic camera. In order to carry out the tests, it was built an equipment consisting of an expanded polystyrene box and a cylindrical aluminum rod, painted black, embedded in this box. The inserted portion in the box was immersed in a temperature-controlled water bath, and the temperature profile of the portion exposed to air was determined. The experimental data were compared to predicted values, in the traditional theoretical model, which considers only convective heat transfer on the fin surface, and with a modified model, in which radiative heat transfer is also computed on this surface. The results obtained indicate the need to consider heat transfer by radiation and the suitability of the proposed methodology in determining the temperature profile in fins and the use of the experiment for didactic purposes

Propriedades moleculares e mecanismos de reação

No trabalho proposto, um modelo quântico é desenvolvido para estabelecer um método de planejamento de sínteses orgânicas. O método é baseado em uma nova solução analítica para a equação de Schrödinger independente do tempo. O principal diferencial do método proposto é a otimização de tempo de processamento que cresce linearmente com o aumento do número de átomos que formam o sistema químico. Simulações analíticas são apresentadas.In this work a quantum model is developed in order to establish a method for planning organic synthesis. The method is based on a new analytical solution for the time-independent Schrödinger equation. The main difference of the proposed method is the optimization of total time processing which increases linearly with number of atoms made by the chemical system here presented. Analytical simulations are reported

Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good

Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation

One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced. Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI

Search for stop and higgsino production using diphoton Higgs boson decays

Results are presented of a search for a "natural" supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top-quark (stop) and the Higgs boson (higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7 inverse femtobarns of proton-proton collision data at sqrt(s) = 8 TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the stop mass below 360 to 410 GeV, depending on the higgsino mass

Severe early onset preeclampsia: short and long term clinical, psychosocial and biochemical aspects

Preeclampsia is a pregnancy specific disorder commonly defined as de novo hypertension and proteinuria after 20 weeks gestational age. It occurs in approximately 3-5% of pregnancies and it is still a major cause of both foetal and maternal morbidity and mortality worldwide1. As extensive research has not yet elucidated the aetiology of preeclampsia, there are no rational preventive or therapeutic interventions available. The only rational treatment is delivery, which benefits the mother but is not in the interest of the foetus, if remote from term. Early onset preeclampsia (<32 weeks’ gestational age) occurs in less than 1% of pregnancies. It is, however often associated with maternal morbidity as the risk of progression to severe maternal disease is inversely related with gestational age at onset2. Resulting prematurity is therefore the main cause of neonatal mortality and morbidity in patients with severe preeclampsia3. Although the discussion is ongoing, perinatal survival is suggested to be increased in patients with preterm preeclampsia by expectant, non-interventional management. This temporising treatment option to lengthen pregnancy includes the use of antihypertensive medication to control hypertension, magnesium sulphate to prevent eclampsia and corticosteroids to enhance foetal lung maturity4. With optimal maternal haemodynamic status and reassuring foetal condition this results on average in an extension of 2 weeks. Prolongation of these pregnancies is a great challenge for clinicians to balance between potential maternal risks on one the eve hand and possible foetal benefits on the other. Clinical controversies regarding prolongation of preterm preeclamptic pregnancies still exist – also taking into account that preeclampsia is the leading cause of maternal mortality in the Netherlands5 - a debate which is even more pronounced in very preterm pregnancies with questionable foetal viability6-9. Do maternal risks of prolongation of these very early pregnancies outweigh the chances of neonatal survival? Counselling of women with very early onset preeclampsia not only comprises of knowledge of the outcome of those particular pregnancies, but also knowledge of outcomes of future pregnancies of these women is of major clinical importance. This thesis opens with a review of the literature on identifiable risk factors of preeclampsia

Search for anomalous production of events with three or more leptons in pp collisions at √s = 8TeV

Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published articles title, journal citation, and DOI.A search for physics beyond the standard model in events with at least three leptons is presented. The data sample, corresponding to an integrated luminosity of 19.5fb-1 of proton-proton collisions with center-of-mass energy s=8TeV, was collected by the CMS experiment at the LHC during 2012. The data are divided into exclusive categories based on the number of leptons and their flavor, the presence or absence of an opposite-sign, same-flavor lepton pair (OSSF), the invariant mass of the OSSF pair, the presence or absence of a tagged bottom-quark jet, the number of identified hadronically decaying τ leptons, and the magnitude of the missing transverse energy and of the scalar sum of jet transverse momenta. The numbers of observed events are found to be consistent with the expected numbers from standard model processes, and limits are placed on new-physics scenarios that yield multilepton final states. In particular, scenarios that predict Higgs boson production in the context of supersymmetric decay chains are examined. We also place a 95% confidence level upper limit of 1.3% on the branching fraction for the decay of a top quark to a charm quark and a Higgs boson (t→cH), which translates to a bound on the left- and right-handed top-charm flavor-violating Higgs Yukawa couplings, λtcH and λctH, respectively, of |λtcH|2+|λctH|2<0.21