11 research outputs found
Further considerations of magnetic deinking for wastepaper recycling mills
Journal ArticleMagnetic de-inking has been shown to be an efficient process for the removal of certain toner particles from mixed office waste (MOW) furnishes. It is possible to achieve a dirt removal of 96% with the WHIMS (wet high intensity magnetic separator) if all toner particles present in the furnish are at least paramagnetic. However, the recycled MOW has a variety of toner particles thai vary from non-magnetic to ferromagnetic and , under these circumstance, it may be necessary to combine flotation with WHIMS in order to achieve a satisfactory level of dirt removal. On the other hand, flotation may not be necessary if agglomeration of non-magnetic and magnetic toner particles can be accomplished. In this regard, conditions for toner agglomeration have been examined and the toner agglomeration characterized. Specifically, the magnetic susceptibility of such aggregates has been measured in order to facilitate efficient magnetic de-inking for wastepaper recycle mills
Agglomeration and magnetic deinking for office paper
Journal ArticleMagnet deinking of office paper (OP) is a promising technology for the production of high quality secondary fiber. The technique is possible because a significant portion of the toner in OP furnish has a magnetic character. Toner magnetic susceptibility can vary from weakly paramagnetic to ferromagnetic depending on the iron oxide content of the toner partides.The amount of iron oxide in toners varies. It can contain as much as 65% by weight depending on the type of image development process used by electrophotography machines
Effect of pH on pulping and flotation of mixed office wastepaper
Journal ArticleThe effect of pulping reagents on the deinking flotation of laser-printed wastepaper was investigated with regard to the removal efficiency of toner and mineral filler particles at different pH values. These results show that caustic pulping causes the toner to be released from the fibres as larger particles and a poor flotation response is obtained. On the other hand, neutral pulping not only causes the toner to be released as smaller particles but also increases the simultaneous flotation removal of toner and mineral filler particles. On the basis of these flotation results and atomic force microscopy force experiments, it is known that the remarkable removal of mineral fillers and toner particles under acidic conditions is related to the heterocoagulation of toner and filler particles
Desafíos para la recolección de sangre y el análisis bioquímico en un gran estudio multicéntrico con adolescentes en las escuelas : lecciones del ERICA en Brasil
O Estudo de Riscos de Cardiovasculares em Adolescentes (ERICA) é um estudo pioneiro que tem como objetivo avaliar a prevalência de fatores de risco cardiovascular, incluindo componentes da síndrome metabólica, entre adolescentes brasileiros. Este artigo tem como objetivo descrever os aspectos metodológicos relacionados com a coleta de sangue, assim como informar os resultados da preparação, transporte, armazenamento e exames no ERICA. Os exames foram realizados em um único laboratório e as amostras de sangue foram coletadas de forma padronizada. A logística envolveu o transporte aéreo das amostra até o laboratório de referência, com a temperatura controlada desde a coleta do sangue. O soro foi armazenado em biorrepositores locais em quatro centros e se serão utilizados em análises futuras. Durante o estudo foram realizados 284.247 exames e a taxa de participação foi de 56,2%, representando 40.732 adolescentes. Do total, 92,6% das amostras chegaram ao laboratório de referência mantendo a temperatura entre 0-10°C. Não foram identificadas alterações clínicas significativas nos resultados devido a mudanças de temperatura. O controle de qualidade externo registrou resultados satisfatórios em 98,7% das avaliações. Foram criados quatro biorrepositores com amostras de 7.785 adolescentes. Assim, podemos considerar que a logística adotada no ERICA foi bastante exitosa e sua descrição, tal como as dificuldades experimentadas no Brasil, podem informar e facilitar o planejamento de futuros estudos, especialmente nos países em desenvolvimento.The Study of Cardiovascular Risk in Adolescents (ERICA) is a pioneering study that aimed to assess the prevalence of cardiovascular risk factors, including metabolic syndrome components in Brazilian adolescents. This study aims to describe the methodological aspects related to blood collection as well as to report pertaining results of the preparation, transport, storage, and exams in ERICA. Exams in ERICA were performed in a single laboratory and blood samples were collected in schools in a standardized manner. Logistics involved air transportation of samples to the reference laboratory with controlled temperature since sample collection. The serum was stored in local biorepositories in four centers to be used in future analyses. During the study, 284,247 exams were performed and rate of participation in exams was 56.2%, thus involving 40,732 adolescents. From the total, 92.6% of the samples reached the reference laboratory maintaining the temperature between 0-10°C. No clinical significant changes in results due to temperature changes were identified. External quality control recorded satisfactory results in 98.7% of the evaluations. Four biorepositories with samples of 7,785 adolescents were created. Thus, we can consider that the logistics adopted in ERICA was fairly successful and description of this as well as the difficulties experienced in Brazil can inform and facilitate the planning of future studies, especially in developing countries.El Estudio de Riesgos Cardiovasculares en Adolescentes (ERICA) es un estudio pionero que tiene como objetivo evaluar la prevalencia de factores de riesgo cardiovascular, incluyendo componentes del síndrome metabólico en adolescentes brasileños. Este estudio tiene como objetivo describir los aspectos metodológicos relacionados con la recolección de sangre, así como informar sobre los resultados de la preparación, transporte, almacenamiento y exámenes en el ERICA. Los exámenes en ERICA se realizaron en un solo laboratorio y se recogieron muestras de sangre en las escuelas de manera estandarizada. La logística involucró el transporte aéreo de muestras al laboratorio de referencia con temperatura controlada desde la recolección de muestras. El suero fue almacenado en biorepositories locales en cuatro centros que se utilizarán en análises futuros. Durante el estudio se realizaron 284.247 exámenes y la tasa de participación fue de 56,2%, lo que involucró a 40.732 adolescentes. Del total, el 92,6% de las muestras alcanzaron el laboratorio de referencia manteniendo la temperatura entre 0-10°C. No se identificaron cambios clínicos significativos en los resultados debido a cambios de temperatura. El control de calidad externo registró resultados satisfactorios en el 98,7% de las evaluaciones. Se crearon cuatro biorrepositores con muestras de 7.785 adolescentes. Así, podemos considerar que la logística adoptada en el ERICA fue bastante exitosa y su descripción así como las dificultades experimentadas en Brasil pueden informar y facilitar la planificación de futuros estudios, especialmente en los países en desarrollo
Challenges for conducting blood collection and biochemical analysis in a large multicenter school-based study with adolescents: lessons from ERICA in Brazil
Adaptação transcultural do pressure ulcer scale for healing (PUSH) para a língua portuguesa Adaptación transcultural del pressure ulcer scale for healing para el idioma portugués Crosscultural adaptation of the pressure ulcer scale for healing to the portuguese language
O objetivo do estudo foi realizar a adaptação transcultural do Pressure Ulcer Scale for Healing (PUSH) para a língua portuguesa, através da tradução do instrumento para a língua portuguesa, feita por especialistas bilingües e comitê de especialistas, e teste das propriedades de medida: confiabilidade interobservadores e validade convergente. Para tais análises foram utilizados o índice Kappa e os Testes de Fisher e Spearman. Após aprovação pelo Comitê de Ética da Escola de Enfermagem da Universidade de São Paulo, 34 úlceras de pressão foram examinadas. Os resultados obtidos para os índices Kappa (0,90 a 1,0) entre as observações dos enfermeiros e estomaterapeutas (padrão-ouro) para todas as subescalas e escore total da escala, bem como a existência de correlação positiva e estatisticamente significativa (p<0,001) entre as observações relativas à classificação das úlceras em estágios e escore total da escala, atestaram ambas as propriedades de medida, confirmando a futura utilização do PUSH, versão adaptada, em nosso meio.<br>La finalidad de este estudio fue efectuar la adaptación transcultural del Pressure Ulcer for Healing Scale para el portugués, mediante la traducción del instrumento al portugués (por especialistas bilingües); y la validación de la confiabilidad inter-observadores y validad convergente. Para los análisis fueron usados el Índice Kappa y los test de Fisher y Spearman, respectivamente. Después de la aprobación del proyecto por el Comité de Ética de la Escuela de Enfermería de USP, 34 úlceras por presión fueran evaluadas. Los índices de Kappa (0.90 al 1.0) obtenidos entre las observaciones de los enfermeros y estomaterapeutas para todas las subescalas y puntuación total y la presencia de correlaciones estadísticas significativas (p<0,001) entre todas las observaciones del estadio y puntuación total confirmaran sus propiedades de medida y el futuro uso del PUSH versión adaptada, en nuestra cultura.<br>This study aimed to carry out a crosscultural adaptation of the Pressure Ulcer Scale for Healing (PUSH) to the Portuguese language through the translation of the instrument into Portuguese (by bilingual specialists and a specialist committee) and the validation of inter-rater reliability (comparison between nurses' and stomal therapists' observations) and convergent validity (correlation between pressure ulcers - PU - stages and type of tissue factor and total scale score). Besides the Kappa index, we also used Fisher's and Spearman's Tests. The Kappa indices (0.90 to 1.00) obtained for the comparison between all nurses and stomal therapists' observations for all sub-scales and for the total score and the presence of a positive and statistically significant correlation (p<0.001) between PU stages and total score for nurses and stomal therapists confirmed both scales' measuring properties, thus pointing towards the future use of the PUSH adapted version in the Portuguese culture
A investigação em fonologia do português Research in Portuguese phonology
Neste artigo pretende-se traçar uma panorâmica dos estudos de fonologia realizados em Portugal, com especial incidência nas análises formalizadas que se desenvolveram a partir da obra de Chomsky e Halle (1968). Na Introdução referem-se obras que marcaram a fonologia do Português Europeu antes dessa data, e apresentam-se os principais trabalhos de carácter dialectal e filológico, os estudos fonéticos e as obras que se integram na linguística estrutural. Na apresentação das análises formais distingue-se a fonologia generativa clássica das teorias que lhe sucederam O artigo tem um anexo que contém a bibliografia exaustiva dos livros e artigos publicados em Portugal a partir dos anos 70.<br>This paper is an overview of the phonological studies in Portuguese starting with the formal analyses developed in Portugal after the publication of The Sound Pattern of English (1968). The relevant works on European Portuguese published before Chomsky & Halle are included in the Introduction: the most important dialectal and philological works, phonetic studies as well as structural descriptions. Formal analyses are divided in two parts: those that follow standard generative phonology and those oriented by subsequent theories. The annex includes a comprehensive bibliography of all phonological books and papers published in Portugal after the seventies
Challenges for conducting blood collection and biochemical analysis in a large multicenter school-based study with adolescents: lessons from ERICA in Brazil
Abstract: The Study of Cardiovascular Risk in Adolescents (ERICA) is a pioneering study that aimed to assess the prevalence of cardiovascular risk factors, including metabolic syndrome components in Brazilian adolescents. This study aims to describe the methodological aspects related to blood collection as well as to report pertaining results of the preparation, transport, storage, and exams in ERICA. Exams in ERICA were performed in a single laboratory and blood samples were collected in schools in a standardized manner. Logistics involved air transportation of samples to the reference laboratory with controlled temperature since sample collection. The serum was stored in local biorepositories in four centers to be used in future analyses. During the study, 284,247 exams were performed and rate of participation in exams was 56.2%, thus involving 40,732 adolescents. From the total, 92.6% of the samples reached the reference laboratory maintaining the temperature between 0-10°C. No clinical significant changes in results due to temperature changes were identified. External quality control recorded satisfactory results in 98.7% of the evaluations. Four biorepositories with samples of 7,785 adolescents were created. Thus, we can consider that the logistics adopted in ERICA was fairly successful and description of this as well as the difficulties experienced in Brazil can inform and facilitate the planning of future studies, especially in developing countries
Surface modification of a granite building stone in central Rio de Janeiro
In order to evaluate environmental controls on the soiling formation and decay of building stones a set of mapping and physical and chemical analyses were carried out on granite from a historical church in the polluted centre of Rio de Janeiro. These techniques highlight the increasing of threatening damage on generally perceived as a durable building material, caused by granular disaggregation and contour scaling in areas close to ground level. Mapping also indicated the formation of black crusts over entire building façades, concentrated on areas sheltered from rain-wash. Analyses demonstrated the influence of marine aerosols, rock and mortar composition and mostly of the atmospheric pollutants on the decay and soiling of the granite. Much of the decay is associated specifically with the presence of halite (NaCl) and gypsum (CaS04.2H2O). The fact that black, gypsum crusts are able to develop over entire façades in a humid subtropical environment is testimony to the high levels of local pollution, especially particulate deposition. Reduced rainwash, in sheltered micro-environments of narrow, canyon-like streets, overcomes the gypsum tendency to bewashed away from buildings façades. These observations further highlight that decay processes are primarily controlled by microclimatic conditions.<br>Com o objetivo de se avaliar os controles ambientais na formação de crostas e deterioração de rochas ornamentais em fachadas de prédios históricos, uma série de mapeamentos e análises fisicas e químicas foram realizados em granitos da fachada de uma igreja histórica numa área poluída no centro da cidade do Rio de Janeiro. Estas técnicas destacam a ameaça crescente dos danos causados pela desagregação granular e esfoliação da rocha que é fortemente percebido por se tratar de um material de alta durabilidade usado na fachada do prédio em áreaslocalizadas ao nível do chão. O exercício de mapeamento possibilitou a demarcação e observação das áreas afetadas pela formação de crosta negra sobre toda a fachada do prédio, principalmente concentradas em áreas abrigadas da ação da chuva. As análises demonstraram a influência de aerosóis marinhos, composição das rochas e argamassas e dos poluentes atmosféricos na deterioração e formação de crostas no granito. Muito da deterioração é associado especificamente a presença de sais, tais como halita (NaCl) e gipsita (CaS0(4).2H2O). O fato da crosta negra de gipsita ser capaz de se desenvolver sobre toda a fachada do prédio, em um ambiente sub-tropical úmido é testemunha da eficácia dos altos níveis de poluição local, especialmente da deposição de particulados, e da reduzida lavagem pela chuva em um micro-ambiente protegido,em ruas estreitas, que funcionam como corredores de poluição, impedindo a tendência da gipsita ser lavada das fachadas dos prédios históricos. Essa observação destaca que os processos de intemperismo operante, são principalmente controlados por condições microclimáticas