62 research outputs found
Mitigação do risco ambiental da descarga de efluentes hospitalares : contribuição para a remoção de fármacos
As atividades existentes nas unidades hospitalares implicam o consumo de grandes
quantidades de água e medicamentos, produzindo efluentes com características
específicas, sendo, muitas vezes, descarregadas para a rede pública de saneamento sem
tratamento prévio adequado, contribuindo para a persistência de micropoluentes
emergentes, quer nas águas residuais urbanas, quer nos meios hídricos recetores.
Numa abordagem holística deste problema ambiental, o trabalho de investigação em curso iniciou-se com uma caracterização da atual situação dos sistemas de pré-tratamento dos hospitais portugueses, visando obter uma melhor perceção do seu potencial risco ambiental, através de um inquérito por questionário às respetivas entidades gestoras. Os resultados obtidos permitem constatar que apenas 38% da amostra respondente ao inquérito efetuado dispõe de um sistema de pré-tratamento.
Posteriormente, procedeu-se à realização dum estudo experimental visando avaliar as
potencialidades da aplicação de processos de oxidação avançada (POA), com dióxido de
titânio, na fotodegradação de fármacos, tendo-se selecionado o antibiótico oxitetraciclina (OTC), muito utilizado em hospitais e unidades aquícolas. A maior eficiência de degradação da OTC foi de 96%, obtida nos ensaios de fotocatálise heterogénea, sob radiação da lâmpada UV, com um tempo de exposição de uma hora, confirmando as potencialidades deste processo de tratamento.
Os ensaios de toxicidade realizados às soluções resultantes do tratamento por fotocatálise heterogénea revelaram que os compostos obtidos não induzem toxicidade nas águas.Fundação para a Ciência e a Tecnologia (FCT
Adubo de liberação lenta na produção de mudas micropropagadas de Bananeira CV. BRS Tropical.
No cultivo da bananeira têm-se utilizado mudas oriundas de micropropagação, que no desenvolvimento em substratos comerciais, geralmente são realizadas aplicações frequentes de nutrientes, para adequado crescimento. A utilização de adubos de liberação de lenta dos nutrientes é uma alternativa para aumento de eficiência (1, 2).
O efeito da adição de 40% de cinzas volantes sobre o ingresso de cloretos no betão face à ação combinada entre a carbonatação e os iões cloreto
Além de imprimir um caráter sustentável ao betão, as cinzas volantes (CV) têm sido bastante
utilizadas para tornar a matriz cimentícia mais resistente à penetração de
Cl-uma vez
que tornam a estrutura porosa mais densa e ajudam a fixar Cl-. Por outro lado, sabe-se que
o Ca(OH)2 existente na matriz é parcialmente consumido pelas reações pozolânicas,
facilitando o avanço da carbonatação
e, consequentemente, aumentando a quantidade de Cl-livres.
Considerando a ação conjunta destes agentes, especula-se sobre o
papel das CV na penetração de Cl-. Foram moldados provetes com 0% e
40% de CV. Após 90 dias de cura os provetes foram submetidos a
12 ciclos de imersão em solução com NaCl
e secagem
em câmara de carbonatação , num total de 168 dias.
Observou-se que os provetes contendo CV, e submetidos à ação combinada, apresentaram perfis de
Cl-com teores superiores quando comparados à ação exclusiva dos
Cl
Adsorption of yellow lanasol 4g reactive dye in a simulated textile effluent on gallinaceous feathers
Adsorption is one of the most efficient physicochemical processes known to remove colour in textile industry effluents. Activated charcoal is conventionally the most used material for this purpose and although its efficiency is very high also is its price. The aim of this study was to know the variables that influence the adsorption process of wool reactive dye Yellow Lanasol 4G in a simulated textile effluent, on an inexpensive and abundant material, gallinaceous feathers, so as to optimize the operating conditions. Factorial experimentation within a certain domain was used to determine the influence level of several parameters, such as, temperature, initial pH of the solution, "size" and adsorbent's concentration and their interactions. A statistical analysis of the results showed that within the selected domain all the parameters have influence at a significance level of 1% excepting initial pH that only has influence at a significance level of 5%. Some of the possible interactions between these parameters also have significant influence on the adsorption process specially first order ones, including significance levels of 5 and 1%. In industrial practice it will be possible to take advantage of the prominent effect of a temperature increase on adsorption capacity as effluents of wool dyeing baths are already at an elevated temperature. Besides that as the influence of "granulometry" becomes rather smaller for higher temperatures there will be no need to grind the adsorbent. This means then that optimization of operating conditions in industrial wastewaters treatment using the studied adsorption technique will not imply additional costs except those concerning pH adjustment. This emphasizes the importance of gallinaceous feathers as an alternative to activated carbon.(undefined
Courtship and agonistic sounds by the cichlid fish Pseudotropheus zebra
Courtship and agonistic interactions in an African cichlid species present a richer diversity of
acoustic stimuli than previously reported. Male cichlids, including those from the genus
Pseudotropheus (P.), produce low frequency short pulsed sounds during courtship. Sounds emitted
by P. zebra males in the early stages of courtship during quiver were found to be significantly
longer and with a higher number of pulses than sounds produced in later stages. During agonistic
intrasexual quiver displays, males produced significantly longer sounds with more pulses than
females. Also, male sounds had a shorter duration and pulse period in courtship than in male–male
interactions. Taken together, these results show that the acoustic repertoire of this species is larger
than what was previously known and emphasize the importance of further research exploiting the
role of acoustic stimuli in intra- and interspecific communication in African cichlids
Cellulosic films obtained from the treatment of sugarcane bagasse fibers with N -methylmorpholine- N -oxide (NMMO)
Ethanol/water organosolv pulping was used to obtain sugarcane bagasse pulp
that was bleached with sodium chlorite. This bleached pulp was used to obtain cellulosic
films that were further evaluated by Fourier transform infrared (FTIR) spectroscopy,
thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). A good film
formation was observed when temperature of 74 °C and baths of distilled water were used,
which after FTIR, TGA, and SEM analysis indicated no significant difference between the
reaction times. The results showed this to be an interesting and promising process,
combining the prerequisites for a more efficient utilization of agro-industrial residues.Fundação de Amparo à Pesquisa
do Estado de São Paulo (FAPESP), (CNPq), and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Brazil; Fundação para a Ciência e a Tecnologia (FCT) and CEMU
The ATLAS trigger - high-level trigger commissioning and operation during early data taking
The ATLAS experiment is one of the two general-purpose experiments due to start operation soon at the Large Hadron Collider (LHC). The LHC will collide protons at a centre of mass energy of 14~TeV, with a bunch-crossing rate of 40~MHz. The ATLAS three-level trigger will reduce this input rate to match the foreseen offline storage capability of 100-200~Hz. This paper gives an overview of the ATLAS High Level Trigger focusing on the system design and its innovative features. We then present the ATLAS trigger strategy for the initial phase of LHC exploitation. Finally, we report on the valuable experience acquired through in-situ commissioning of the system where simulated events were used to exercise the trigger chain. In particular we show critical quantities such as event processing times, measured in a large-scale HLT farm using a complex trigger menu
Phenological synchrony and seasonality of understory Rubiaceae in the Atlantic Forest, Bahia, Brazil
The ATLAS Trigger/DAQ Authorlist, version 1.0
This is a reference document giving the ATLAS Trigger/DAQ author list, version 1.0 of 20 Nov 2008
The ATLAS Trigger/DAQ Authorlist, version 3.0
This is the ATLAS Trigger/DAQ Authorlist, version 3.0, 11 September 200
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