993 resultados para removing


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The oxidation of water to oxygen by bromate ions is mediated by the heterogeneous redox catalyst ruthenium-Adams, a high surface area and very stable form of ruthenium(IV) oxide. The initial kinetics of catalysis are investigated as a function of [BrO3-], [Ru-Adams], temperature and [anion], where ''anion'' = ClO4- Cl- or Br-. An electrochemical model of heterogeneous redox catalysis, in which the two participating redox couples are both electrochemically irreversible, is used to interpret most of the kinetic data. The observed inhibition of the initial rate of the redox reaction by Cl- and, especially, Br- ions is tentatively attributed to competitive adsorption. In the presence of organic species, such as methanol, ethanol and propan-1-ol, which are more easily oxidised than water by bromate ions, the rate of BrO3- ion reduction is significantly faster, i.e. ca 24-34 times.

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Veterinary use of the nonsteroidal anti-inflammatory (NSAID) drug diclofenac in South Asia has resulted in the collapse of populations of three vulture species of the genus Gyps to the most severe category of global extinction risk. Vultures are exposed to diclofenac when scavenging on livestock treated with the drug shortly before death. Diclofenac causes kidney damage, increased serum uric acid concentrations, visceral gout, and death. Concern about this issue led the Indian Government to announce its intention to ban the veterinary use of diclofenac by September 2005. Implementation of a ban is still in progress late in 2005, and to facilitate this we sought potential alternative NSAIDs by obtaining information from captive bird collections worldwide. We found that the NSAID meloxicam had been administered to 35 captive Gyps vultures with no apparent ill effects. We then undertook a phased programme of safety testing of meloxicam on the African white-backed vulture Gyps africanus, which we had previously established to be as susceptible to diclofenac poisoning as the endangered Asian Gyps vultures. We estimated the likely maximum level of exposure (MLE) of wild vultures and dosed birds by gavage (oral administration) with increasing quantities of the drug until the likely MLE was exceeded in a sample of 40 G. africanus. Subsequently, six G. africanus were fed tissues from cattle which had been treated with a higher than standard veterinary course of meloxicam prior to death. In the final phase, ten Asian vultures of two of the endangered species (Gyps bengalensis, Gyps indicus) were dosed with meloxicam by gavage; five of them at more than the likely MLE dosage. All meloxicam-treated birds survived all treatments, and none suffered any obvious clinical effects. Serum uric acid concentrations remained within the normal limits throughout, and were significantly lower than those from birds treated with diclofenac in other studies. We conclude that meloxicam is of low toxicity to Gyps vultures and that its use in place of diclofenac would reduce vulture mortality substantially in the Indian subcontinent. Meloxicam is already available for veterinary use in India.

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The present invention relates to a process for the removal of mercury from a mercury- containing hydrocarbon fluid feed using specifically selected ionic liquids comprising, contacting the mercury-containing hydrocarbon fluid feed with an ionic liquid having the formula[Cat+][M+][X-] and separating from the ionic liquid a hydrocarbon fluid product having a reduced mercury content compared to the mercury-containing fluid feed.

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This invention relates to a process for removing metals, particularly mercury, from hydrocarbon streams by use of an ionic liq., where in the metal-contg. hydrocarbon stream is contacted with an ionic liq. to produce a product hydrocarbon stream having reduced mercury content. [on SciFinder(R)]

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Dissertação de Mestrado, Gestão da Água e da Costa, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2007

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STRIPPING is a software application developed for the automatic design of a randomly packing column where the transfer of volatile organic compounds (VOCs) from water to air can be performed and to simulate it’s behaviour in a steady-state. This software completely purges any need of experimental work for the selection of diameter of the column, and allows a choice, a priori, of the most convenient hydraulic regime for this type of operation. It also allows the operator to choose the model used for the calculation of some parameters, namely between the Eckert/Robbins model and the Billet model for estimating the pressure drop of the gaseous phase, and between the Billet and Onda/Djebbar’s models for the mass transfer. Illustrations of the graphical interface offered are presented.

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Epilepsy is a chronic neurological disorder characterized by recurrent seizures (Stein & Kanner, 2009). The purpose of this study was to understand the essence of being a young woman living with epilepsy using heuristic inquiry (Moustakas, 1990). The research was built upon the assumption that each experience is unique, yet commonalities exist. Five women aged 22 to 28 years living with epilepsy were interviewed. Additionally, the researcher described her life with epilepsy. Participants characterized life with epilepsy as a transformative journey. The act of meeting and interacting with another woman living with epilepsy provided an opportunity to remove themselves from the shadows and discuss epilepsy. Three major themes of seizures, medical treatment, and social relationships were developed revealing a complex view of an illness requiring engaged advocacy in the medical system. Respondents frequently make difficult adjustments to accommodate epilepsy. This study provides a complex in-depth view of life with epilepsy.

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Law is often the source of social discriminations, but, at the same time, it can be thekey to delete these social discriminations. The authors try to give an example of thisphenomenon, by analyzing the impact of the Italian citizenship’s rules over the descendantsof the Italian citizens emigrated abroad and, especially, in South America.Indeed, according to the former Italian law, only fathers could transmit iure sanguinisthe citizenship to their children: moreover, women automatically lost theItalian citizenship if they get a foreign citizenship by concluding a marriage witha foreign husband.These rules hardly discriminate the Italian women emigrated abroad and, especially,their descendants who were prevented to get the Italian’s citizenship.These discriminatory rules were finally deleted by the Italian Constitutional Courtin the Seventies and in the Eighties: however, the effects of those rules still persisted,since the decision of the Constitutional Court could not overcome the temporal limit of the entry into force of the Constitution (01.01.1948) and, therefore, could not“cover” the discriminatory facts occurred before that date.Finally in 2009, the Italian Supreme Court, by extending the effects ratione temporisof the decisions of the Constitutional Court, “reopened the doors” of the Italiancitizenship to a huge number of Italian citizenship born from Italian women beforethe 01.01.1948.Therefore, the authors focus on the social impact of this decision for all the potentialItalian citizens living in South America and try to assess its juridical effects overthe Italian law.

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El manual se centra en la enseñanza y el aprendizaje de los estudiantes con dislexia en la escuela secundaria y proporciona orientación práctica para los directores y profesores. Pone de relieve los obstáculos que tienen los estudiantes disléxicos en el currículo de hoy. Da información sobre cómo influye la dislexia en el acceso y el progreso de los estudiantes en la enseñanza secundaria, cómo los profesores pueden minimizar estas barreras identificando posibles obstáculos en el aprendizaje, las estrategias de apoyo para las resoluciones de las necesidades y elevar el logro de los estudiantes disléxicos.

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A sampling oscilloscope is one of the main units in automatic pulse measurement system (APMS). The time jitter in waveform samplers is an important error source that affect the precision of data acquisition. In this paper, this kind of error is greatly reduced by using the deconvolution method. First, the probability density function (PDF) of time jitter distribution is determined by the statistical approach, then, this PDF is used as convolution kern to deconvolve with the acquired waveform data with additional averaging, and the result is the waveform data in which the effect of time jitter has been removed, and the measurement precision of APMS is greatly improved. In addition, some computer simulations are given which prove the success of the method given in this paper.

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This note describes a simple procedure for removing unphysical temporal discontinuities in ERA-Interim upper stratospheric global mean temperatures in March 1985 and August 1998 that have arisen due to changes in satellite radiance data used in the assimilation. The derived temperature adjustments (offsets) are suitable for use in stratosphere-resolving chemistry-climate models that are nudged (relaxed) to ERA-Interim winds and temperatures. Simulations using a nudged version of the Canadian Middle Atmosphere Model (CMAM) show that the inclusion of the temperature adjustments produces temperature time series that are devoid of the large jumps in 1985 and 1998. Due to its strong temperature dependence, the simulated upper stratospheric ozone is also shown to vary smoothly in time, unlike in a nudged simulation without the adjustments where abrupt changes in ozone occur at the times of the temperature jumps. While the adjustments to the ERA-Interim temperatures remove significant artefacts in the nudged CMAM simulation, spurious transient effects that arise due to water vapour and persist for about 5 yr after the 1979 switch to ERA-Interim data are identified, underlining the need for caution when analysing trends in runs nudged to reanalyses.