Revitaliza����o do Rio Golandim (RN/Brasil) ap��s d��cadas de contamina����o por efluentes industriais e dom��sticos: este rio est�� recuperado?

Environmental pollution causes the loss of the quality of aquatic resources and also affects the health of human beings. The Golandim River is located in S��o Gon��alo do Amarante (RN Brazil) and had its water recovered seven years ago by measurements of parameters of the water s quality analyses physicochemistry, microbiological and heavy metals. However, it is not well established if this river is truly recovered, so this study provides a wide knowledge about the quality of these waters. Therefore, this investigation was accomplished by assays of ecotoxicology utilizing Ceriodaphnia dubia and of genotoxicity of the river s water using a biomarker Tradescantia Pallida (Trad-MCN). In set, it carried through a study of environmental perception through questionnaires that approached questions related to the profile of the interviewed one, knowledge on the environment and of the river Golandim with the community that lives in the neighborhoods of the river to diagnosis as they perceive the environment where live and its problems. The assays of the water had been carried out by collecting samples in three different sites of the Golandim River. They were collected between the periods of December 2010 (dry season in the northeast of Brazil) and July 2011 (rainy season in the northeast of). The analysis of the data allowed observing that the majority of the inhabitants are adult and presents a global vision of what it is part of the environment, the majority mentions the pollution of the river as one of the problems of the city, considering it serious. The ecotoxicology assay showed that there was not acute toxicity in all three samples collected. Meanwhile, all these three samples demonstrated significant chronic toxicity. The results from the Trad-MCN assay presented an increase in the frequency of micronucleus in one of the sites analyzed (S3) (p<0.01), in both seasons collected. On the other hand, the sites S1 and S2 did not presented a significant increase of micronucleus using this bioassay. The analyses of chemicals detected an increase in the levels of some metals, in different seasons and samples, which can be associates with some compounds found in urban and industrial areas. On the other hand, the physicochemistries parameters demonstrated that the Golandim River is recouped, when compared with the values presented at the CONAMA s legislation. However, these results indicate the presence of compounds capable of inducing chromosomal mutation in plants. On the other hand, the parameters physicistchemistries demonstrate that the river Golandim is if recouping, since when compares the values observed with the legislation of the CONAMA. All these results point to the fact that the Trad-MCN assay was sensitive and efficient biomarker for chromosomal instability and the C. dubia ecotoxicology assay was as though an efficient biomarker of toxicity of water s quality. The results from Trad-MCN associated with the ecotoxicology demonstrates that these analyses are important for environmental monitoring, once the first bioassay described above indicates alterations at the standards of cells and the other one indicates alterations at the standards of organisms. This study alerts for the necessity to carry out biological assays for the analyses of the water s quality

Avalia����o do potencial mutag��nico da ��gua do a��ude de Lucr��cia (RN- Brasil): um enfoque na rela����o sa��de e ambiente

The water quality of many reservoirs in the world has been reduced due to percolation of contaminants to water, which can have natural or anthropogenic origin, increasing the level of genotoxic compounds in aquatic ecosystems. This fact has contributed to the reduction of environmental quality, and commitment the health of living beings that inhabit these ecosystems, including the human population. In this backdrop of reduced water quality, is the Lucrecia dam, which is a major surface water reservoirs by volume of semi-arid region of Rio Grande do Norte, and that has shown contamination by heavy metals, cyanobacteria toxic and the natural presence of Radon. The population that use this source has been showing high rates of cancer, popularly associated with the consumption of this water, with a prevalence about three times higher compared to the whole state of Rio Grande do Norte. Based on this, the present study aimed to evaluate the mutagenic potencial of surface water from the Lucrecia dam, using the Micronucleus Test in Tradescantia pallida (Trad-MN) and in human peripheral blood lymphocytes (CBMN) assay, as well as identify the concentrations of some heavy metals in this water. Water samples were collected on a dry season and a rainy season, in two distinct points. Moreover, in order to bring a completely view about the relationship of man-health-environment in this local, through the knowledge of knowing / acting environmental from residents of Lucrecia, and the use and perceptions they have about the dam of your city, a study of Environmental Perception was carried out with local residents. The results obtained for the both micronucleus test, showed significant results for the three points analyzed. The strongest mutagenic effect was observed in the dry season for both assays. Chemical analyses detected an increase of heavy metal levels in different points and season above the maximum allowed by legislation. Regarding the study of Environmental Perception with local residents, it was observed the knowledge of the environment that the residents have, as well as the strong ties and perceptions with the dam of the city. Thus, the combination of these two aspects (the genetic toxicity tests conducted in the dam together with analysis of environmental perception with the residents of Lucrecia) allowed to draw a more complete diagnosis on the local situation

Desenvolvendo e gerenciando compostagem de res��duos s��lidos urbanos: para gera����o de renda e repasse de tecnologia �� acrevi

Nowadays, as well as in the past decades, the dumping of biodegradable organic waste in landfill is common practice in Brazil, as well as in most parts of the world. Nevertheless due to its rapid decomposition and release of odors, this practice hamper���s the operation and implementation of a recycling system. These facts encouraged our research to find an efficient system for the management of organic waste, not only for the use of official workers responsible for managing these wastes, but also for non-governmental institutions. The Recycling for Life Community Association ��� ACREVI (Associa����o Comunit��ria Reciclando para a Vida), together with the municipal authorities of Mossor��-RN, Brazil, have assumed the social role of collecting and recycling solid waste produced by most of the local population. However, it was observed that the organic waste it collected was not receiving any treatment. This present work aims to make compost with mixed waste (green waste and organic household), and then do chemical analysis of the material in view to use the waste as organic fertilizer. The objective being: to share the knowledge acquired by putting it into a very simple language accessible to people with little education. The experiment was conducted at ACREVI, Mossor�� (RN), and the compost was obtained following the method "windrow", forming three cells (I, II, III) with conical shape, dimensions of 1.6 meters and 2.0 meters in diameter for cells I and II, and 1.0 meters high and 2.0 meters in diameter for cell III. The process was accompanied by analysis: CHN elemental, a variation of cell temperature, humidity, pH, TKN, bulk density, nutrients and heavy metals. Stabilized organic compounds reached the C/N ratio of 10.4/1 cell I and 10.4/1 in the cell II in the cell, showing how good soil conditions, with potential to improve the physical properties of any soil and pH acid soils, has presented the cell III at the end of the process the C/N 26/1, is a high ratio may be associated with the stack size III, thus changing the optimal conditions for the occurrence of the process. The levels of heavy metals in the analyzed compounds were lower than those established by the SDA normative instruction, N�� 27, of 5 June, 2006. The use of pruning trees and grass are used in small-scale composting, while generating a quality compost in the final process, it also created an important condition for a correct sizing of the composting piles. Under the studied conditions it is not advisable to use cells with a height of 1.00 m in height and 2.00 m in diameter, as these do not prevent the rapid dissipation of heat and thus can not be a good product at the end of composting. The composting process in the shed of the association and the preparation of the primer enabled the development of an alternative technology to generate income for members of ACREVI.

Qualidade do solo da camada de cobertura final em ��rea de disposi����o de res��duos no semi��rido tropical

The final disposal of municipal solid waste in unsuitable areas without an infrastructure that meets the health measures and environmental protection, coupled with the lack of technical criteria in phase and decommissioning of the dump can promote environmental degradation. Alternatively to minimize the impacts of this activity for the stabilization of the area by isolating the massive waste with implementation of an adequate and finished by a layer of soil for plant growth final cover system. In this context, the present study aimed to evaluate the quality of the final cover in the area of a disabled dump the tropical semi-arid region in order to assist the process of recovery of these areas. The study area is located in the tropical semi-arid region in S��o Jo��o do Sabugi /RN. Soil samples were collected in the dump area and bushland as a benchmark of quality. To which they were subjected to analysis of physical attributes (particle density, bulk density, grain size and porosity), chemical properties (pH, K + , Na+ , Ca2 + , Mg2 + and Al3 + exchangeable, potential acidity, available phosphorus, sum of bases, CEC, base saturation, aluminum saturation, saturation Na + and adsorption ratio sodium, total organic carbon and total nitrogen) and total and soluble concentrations of heavy metals (Mn, Pb, Zn, Cd, Cu, Mo, Co, Cr, Ba and Ni). The differences between physical and chemical soil under native forest and final cover showing reduction of soil quality in the area off to the dump, which hinders the development of native vegetation and the recovery of the area. The absence of superior waterproofing to allow vertical transfer between the solid waste and the final cover promoted enrichment by chemical elements and heavy metals in excess can impair revegetation. Deficiencies found in the construction process of the final cover point to the need for intervention to accelerate the process of stabilization and recovery of the area of the local ecosystem

Estudo da incorpora����o de res��duos de perfura����o para aplica����o em cimenta����o de po��os de petr��leo

During the drilling of oil and natural gas are generated solid waste, liquid and gaseous. These solid fragments, which are known as cuttings, are carried to the surface through the drilling fluid. Furthermore, this fluid serves to cool the bit, keeping the internal pressure of the well, and others. This solid residue is very polluting, because it has incorporated beyond the drilling fluid, which has several chemical additives harmful to the environment, some heavy metals that are harmful to the environment, such as lead. To minimize the residue generated, are currently being studied numerous techniques to mitigate the problems that such waste can cause to the environment, like addition of cuttings in the composition of soil cement brick masonry construction, addition of cuttings on the clay matrix for the manufacture of solid masonry bricks and ceramic blocks and coprocessing of the cuttings in cement. So, the main objective of this work is the incorporation of cuttings drilling of oil wells, the cement slurry used in the cementing operation of the well. This cuttings used in this study, arising from the formation Pend��ncias, was milled and separated in a sieve of 100 mesh. After grinding had a mean particle sike in order of 86 mm and crystal structure containing phases of quartz and calcite type, characteristic of the Portland cement. Were formulated and prepared slurries of cement with density 13 lb / gal, containing different concentrations of gravel, and realized characterization tests API SPEC 10A and RP 10B. Free water tests showed values lower than 5.9% and the rheological model that best described the behavior of the mixtures was the power. The results of compressive strength (10.3 MPa) and stability (Dr <0.5 lb / gal) had values within the set of operational procedures. Thus, the gravel from the drilling operation, may be used as binders in addition to Portland cement oil wells, in order to reuse this waste and reduce the cost of the cement paste.

Influ��ncia da radia����o ionizante natural no a��ude do boqueir��o (RN): avalia����o de risco sa��de/ambiente

The contamination of water bodies with toxic substances causes a decrease in water quality, representing a risk to public health. In this context, human activities are generally seen as the main sources of water degradation. However, elements found naturally in the environment can also compromise water quality. Thus, the Boqueir��o���s dam, located in the municipality of Parelhas (RN, Brazil), was chosen as area for the development of this study, as its geological region is rich in the emission of natural ionizing radiation that produces byproducts like lead and Radon. Moreover, the area has a strong human influence that enhances the risks of pollutant discharge in this body of water.Thus, the objectives of this study were centered (i) in the analysis of risk perception in the city of Parelhas (RN/Brasil) due to the use of the water from the Boqueir��o Dam; and (ii) in the assessment of water quality in the Dam using methods that quantify, mainly, heavy metals and radiation levels, as well as these toxics potential of inducing mutations on genetic material. The analysis of risk perception showed that the population in the city of Parelhas can perceive a risk in using the water from the dam and that they can recognize factors that influence the water quality. Regarding the second objective, the set of data point to the contamination of the Dam by heavy metals, as well as levels of radioactive parcicles and Radon ��� also present in high concentrations in outdoor air and on soil. Thus, it is possible to infer that the population residing in this area is subjected to injuries caused by exposure to natural and anthropogenic contamination. Our findings corroborate with the perception of the population regarding the risks associated with the use of the Dam for several types of activities. It is expected that the information gathered in this study can substantiate activities and future researches in this semiarid region in the Rio Grande do Norte/Brazil. Also, that the set of data can enable a better understanding of the specific toxicological scenario of risk found for the population and the effect of the contamination for the biota, which aids the development of a future risk assessment and a consequent management of this local issue.

Constru����o de bibliotecas de cDNAs subtra��dos a partir das sementes de Mamona submetidas �� estresse h��drico e an��lise in silico de transcritos potencialmente expressos sob condi����es de estresse: Metalotioneina, prote��na reprimida por auxina de 12.5 kDa e Glutelina tipo-A3

Estresses ambientais abi��ticos s��o fatores que causam respostas ao n��vel molecular, fisiol��gico e morfol��gico em plantas, dependendo tamb��m de sua intensidade e dura����o. �� visto que algumas esp��cies apresentam toler��ncia a condi����es estressantes e ao mesmo tempo s��o fontes naturais de mat��ria prima para ind��stria. Nesse contexto encontra-se a mamona (Ricinus comunnis L.), principal fonte de ��leo de r��cino valorizado por suas aplica����es farmac��uticas e principalmente industriais, vem sendo usada como cultura em regi��es onde a disponibilidade de ��gua �� reduzida, usada como fonte de renda para agricultura da regi��o nordeste brasileira. Visto que pouco se sabe sobre as respostas moleculares que levam essa planta a tolerar regi��es secas e como as sementes, principais foco de interesse, respondem a essa escassez, nesse trabalho foram constru��das duas bibliotecas de cDNAs, onde a partir de uma abordagem subtrativa, continham RNAs diferencialmente expressos em sementes de plantas mamona submetidas ao estresse h��drico durante 5 dias (biblioteca L7), e a outra RNAs diferencialmente expressos em sementes controle (biblioteca L5). A biblioteca L7 apresentou a maior variedade de transcritos com um total de 182. A maior parte das fun����es estabelecidas pelo sistema Gene Ontology - GO, foram direcionadas aos ���Processos Metab��licos��� (526), em segundo ���Respostas a est��mulos��� (57), o terceiro termo mais abundante foram referentes a ���Desenvolvimento���(26). J�� na biblioteca L5, foram encontrados 91 transcritos, com maior parte de suas fun����es referentes a ���Processos Metab��licos���(413), em segundo ���Respostas a est��mulos��� (8) e em terceiro Regula����o (6). Alguns dos transcritos da biblioteca L7 foram escolhidos para an��lise por repetirem-se mais de 3x e n��o aparecerem na biblioteca L5, o que indica uma poss��vel regula����o positiva sobre estresse. As an��lises sobre Metalotione��na (4x), mostraram que a sequ��ncia de proteica apresentava os dom��nios conservados que a caracterizava como tipo II, onde s��o encontrados dois dom��nios funcionais ricos em ciste��na com posi����es altamente conservadas, desempenhando a fun����o de ligar-se a metais pesados, correlacionadas assim como a atividade de elimina����o EROs e defesa contra o estresse oxidativo, al��m de apresentar homologia com a sequ��ncia de Bruguiera gymnorhiza, uma planta de mangue adaptada a ambientes salinos. Analisamos tamb��m os transcritos da referente a prote��na AUXIN-REPRESSED 12.5 KDA (3x), apontada como sendo reprimida pelo horm��nio auxina e associada ao processo de dorm��ncia da semente, �� descrito em uma fam��lia g��nica onde v��rios membros pertencem as vias de resposta ao estresse. Por ��ltimo, analisamos a prote��na GLUTELIN TYPE-A 3 (5x), uma importante prote��na de armazenamento com car��ter hidrof��lico, possivelmente direcionada para o vac��olo. Em nosso trabalho foi poss��vel observar um aumento de transcritos em rela����o a subtra����o controle, possivelmente reflexo do aumento do metabolismo da semente, tanto para resposta defensiva ao estresse h��drico quanto para o amadurecimento r��pido da semente onde foram observados transcritos referentes a resposta oxidativa, controle hormonal, prote��nas de reserva e produ����o de ��leo.

Estudo da efici��ncia eletroqu��mica para tratamento de chorume gerado em aterro sanit��rio brasileiro

This work was performing effluent degradation studies by electrochemical treatment. The electrochemical oxidation (EO) hydroquinone (H2Q) was carried out in acid medium, using PbO2 electrode by galvanostatic electrolysis, applying current densities of 10 and 30 mA/cm2 . The concentration of H2Q was monitored by differential pulse voltammetry (DPV). The experimental results showed that the galvanostatic electrolysis process performance significantly depends on the applied current density, achieving removal efficiencies of 100% and 80 % and 10 applying 30 mA/cm2 , respectively. Furthermore, the electroanalytical technique was effective in H2Q be used as a detection method. In order to test the efficiency of PbO2 electrode, the electrochemical treatment was conducted in an actual effluent, leachate from a landfill. The liquid waste leachate (600ml effluent) was treated in a batch electrochemical cell, with or without addition of NaCl by applying 7 mA/cm2 . The efficiency of EO was assessed against the removal of thermo-tolerant coliforms, total organic carbon (TOC), total phosphorus and metals (copper, cobalt, chromium, iron and nickel). These results showed that efficient removal of coliforms was obtained (100%), and was further decrease the concentration of heavy metals by the cathode processes. However, results were not satisfactory TOC, achieving low total removal of dissolved organic load. Because it is considered an effluent complex were developed other tests with this effluent to monitor a larger number of decontamination parameters (Turbidity, Total Solids, Color, Conductivity, Total Organic Carbon (TOC) and metals (barium, chromium, lithium, manganese and Zinc), comparing the efficiency of this type of electrochemical treatment (EO or electrocoagulation) using a flow cell. In this assay was compared to electro streaming. In the case of the OE, Ti/IrO2-TaO5 was used as the anode, however, the electrocoagulation process, aluminum electrodes were used; applying current densities of 10, 20 and 30 mA/cm2 in the presence and absence of NaCl as an electrolyte. The results showed that EO using Ti/IrO2���TaO5 was anode as efficient when Cl- was present in the effluent. In contrast, the electrocoagulation flow reduces the dissolved organic matter in the effluent, under certain experimental conditions.

Caracteriza����o e separa����o f��sica de placas de circuito impresso de computadores obsoletos

The unbridled consumption of electronic equipment associated with fast immersion of new technologies on the market leads to the accelerated growth of electronic waste. Such waste mostly contains printed circuit boards in its structure. Printed circuit boards have many metals, including heavy metals, being highly toxic. Electronic waste is discarded improperly and indiscriminately, usually without any previous treatment and with other municipal waste, contaminating the environment and causing serious problems to human health. Beyond these metals, there are also precious metals and high value-added basis, that can be recovered and recycled, reducing the exploration of natural resources. Thus, due to the high growth potential and reuse of these waste treatment processes, characterization and separation were applied to the printed circuit boards. The printed circuit boards were subjected to physical treatments such as dismantling, crushing, sizing separation, magnetic separation and chemical treatments such as pyrolysis and leaching. Through characterization process (pyrolysis and leaching) the proportions of the components of the granulometric range were determined: 46,08% of metals; 23,32% of polymers and 30,60% of ceramics. It was also observed by particle size separation that metal components tend to concentrate in coarse fractions, while polymeric and ceramic components in fine fractions. From the magnetic separation process was obtained 12,08% of magnetic material and 82,33% of non-magnetic material.

Aplica����o e otimiza����o de m��todos eletroqu��micos combinados para remo����o e determina����o de cromo hexavalente em efluentes simulados

Hexavalent chromium is a heavy metal present in various industrial effluents, and depending on its concentration may cause irreparable damage to the environment and to humans. Facing this surrounding context, this study aimed on the application of electrochemical methods to determine and remove the hexavalent chromium (Cr6+) in simulated wastewater. To determine was applied to cathodic stripping voltammetry (CSV) using ultra trace graphite electrodes ultra trace (work), Ag/AgCl (reference) and platinum (counter electrode), the samples were complexed with 1,5- diphenylcarbazide and then subjected to analysis. The removal of Cr6+ was applied electrocoagulation process (EC) using Fe and Al electrodes. The variables that constituted the factorial design 24, applied to optimizing the EC process, were: current density (5 and 10 mA.cm-2), temperature (25 and 60 ��C), concentration (50 and 100 ppm) and agitation rate (400 and 600 RPM). Through the preliminary test it was possible the adequacy of applying the CSV for determining of Cr6+, removed during the EC process. The Fe and Al electrodes as anodes sacrifice showed satisfactory results in the EC process, however Fe favored complete removal in 30 min, whereas with Al occurred at 240 min. In the application of factorial design 24 and analysis of Response Surface Methodology was possible to optimize the EC process for removal of Cr6+ in H2SO4 solution (0.5 mol.L-1), in which the temperature, with positive effect, was the variable that presented higher statistical significance compared with other variables and interactions, while in optimizing the EC process for removal of Cr6+ in NaCl solution (0.1 mol.L-1) the current density, with positive effect, and concentration, with a negative effect were the variables that had greater statistical significance with greater statistical significance compared with other variables and interactions. The utilization of electrolytes supports NaCl and Na2SO4 showed no significant differences, however NaCl resulted in rapid improvement in Cr6+ removal kinetics and increasing the NaCl concentration provided an increase in conductivity of the solution, resulting in lower energy consumption. The wear of the electrodes evaluated in all the process of EC showed that the Al in H2SO4 solution (0.5 mol.L-1), undergoes during the process of anodization CE, then the experimental mass loss is less than the theoretical mass loss, however, the Fe in the same medium showed a loss of mass greater experimental estimated theoretically. This fact is due to a spontaneous reaction of Fe with H2SO4, and when the reaction medium was the NaCl and Na2SO4 loss experimental mass approached the theoretical mass loss. Furthermore, it was observed the energy consumption of all processes involved in this study had a low operating cost, thus enabling the application of the EC process for treating industrial effluents. The results were satisfactory, it was achieved complete removal of Cr6+ in all processes used in this study.

Vermiculitas tratadas quimicamente na obten����o de s��lidos microporosos como precursores para h��bridos inorg��nico-org��nicos com aplica����es adsortivas

ALVES, Ana paula Melo. Vermiculitas tratadas quimicamente na obten����o de s��lidos microporosos como precursores para h��bridos inorg��nico-org��nicos com aplica����es adsortivas. 2009. 124 f. Tese (Doutorado em Quimica) - Centro de Ci��ncias Exatas e da Natureza, Universidade Federal da Para��ba, Jo��o Pessoa, PB, 2009.

Diagn��stico ecotoxicol��gico dos efluentes lan��ados no complexo estuarino do Jundia��/Potengi, Natal/RN

Untreated effluents that reach surface water affect the aquatic life and humans. This study aimed to evaluate the wastewater s toxicity (municipal, industrial and shrimp pond effluents) released in the Estuarine Complex of Jundia��- Potengi, Natal/RN, through chronic quantitative e qualitative toxicity tests using the test organism Mysidopsis Juniae, CRUSTACEA, MYSIDACEA (Silva, 1979). For this, a new methodology for viewing chronic effects on organisms of M. juniae was used (only renewal), based on another existing methodology to another testorganism very similar to M. Juniae, the M. Bahia (daily renewal).Toxicity tests 7 days duration were used for detecting effects on the survival and fecundity in M. juniae. Lethal Concentration 50% (LC50%) was determined by the Trimmed Spearman-Karber; Inhibition Concentration 50% (IC50%) in fecundity was determined by Linear Interpolation. ANOVA (One Way) tests (p = 0.05) were used to determinate the No Observed Effect Concentration (NOEC) and Low Observed Effect Concentration (LOEC). Effluents flows were measured and the toxic load of the effluents was estimated. Multivariate analysis - Principal Component Analysis (PCA) and Correspondence Analysis (CA) - identified the physic-chemical parameters better explain the patterns of toxicity found in survival and fecundity of M. juniae. We verified the feasibility of applying the only renewal system in chronic tests with M. Juniae. Most efluentes proved toxic on the survival and fecundity of M. Juniae, except for some shrimp pond effluents. The most toxic effluent was ETE Lagoa Aerada (LC50, 6.24%; IC50, 4.82%), ETE Quintas (LC50, 5.85%), Giselda Trigueiro Hospital (LC50, 2.05%), CLAN (LC50, 2.14%) and COTEMINAS (LC50, IC50 and 38.51%, 6.94%). The greatest toxic load was originated from ETE inefficient high flow effluents, textile effluents and CLAN. The organic load was related to the toxic effects of wastewater and hospital effluents in survival of M. Juniae, as well as heavy metals, total residual chlorine and phenols. In industrial effluents was found relationship between toxicity and organic load, phenols, oils and greases and benzene. The effects on fertility were related, in turn, with chlorine and heavy metals. Toxicity tests using other organisms of different trophic levels, as well as analysis of sediment toxicity are recommended to confirm the patterns found with M. Juniae. However, the results indicate the necessity for implementation and improvement of sewage treatment systems affluent to the Potengi s estuary

Utiliza����o da macroalga Ulva lactuca linnaeus na redu����o de nutrientes (NH4+,NO3- e PO4-2) provenientes da carcinicultura

Dentre as macroalgas capazes de absorver altas concentra����es de N e P dissolvidos na ��gua, destaca-se a Chlorophyta Ulva lactuca, bastante adapt��vel e resistente ��s adversidades ambientais, como grandes varia����es de temperatura, salinidade, mat��ria org��nica e metais pesados. Trata-se tamb��m de uma esp��cie bastante comum nas ��reas intertidais do litoral norte-riograndense. Devido a suas caracter��sticas ecol��gicas, fisiol��gicas e nutricionais, foi avaliado nesse estudo, o seu potencial como biofiltro na redu����o de NH4+, NO3- e PO4-2, tanto em condi����es controladas como tamb��m em um viveiro de camar��o. No experimento laboratorial, foram utilizados quatro aqu��rios de vidro de 30 x 20 x 20cm com 10L de ��gua, sendo tr��s aqu��rios experimentais contendo 20g de U. lactuca e um controle. O acr��scimo de biomassa foi de 2,92g (22,92 �� 6,29g; p < 0,05) em rela����o ao in��culo inicial de 20g, sob temperatura (28,50 �� 0,58��C), salinidade (35,00 �� 0,00 ), pH (8,26 �� 0,02) e luz constante (250 &#956;mol.m2s-1). O crescimento positivo (1,78 �� 4,38%dia-1; p < 0,05), juntamente com a alta efici��ncia de absor����o de am��nio (83%; p < 0,001), nitrato (83%; p < 0,001) e ortofosfato (53%; p < 0,001), demonstrou que, nessas condi����es, a Ulva lactuca absorveu os nutrientes e aumentou sua biomassa. J�� no experimento de campo, realizado na fazenda TECNAR��O, situada no munic��pio de Arez/RN (06�� 11 40 Latitude Sul, e 35�� 09 37 Longitude Oeste), foram utilizadas tr��s gaiolas de PVC, posicionadas a 12cm da superf��cie da ��gua, cada uma com dimens��es de aproximadamente 59 x 59 x 15cm, onde foram colocadas 200g de U. lactuca. O ganho de biomassa de 3g (203,00 �� 41,02g; p < 0,001) foi muito semelhante ��s condi����es controladas, demonstrando a adaptabilidade da esp��cie em condi����es ambientais vari��veis, onde, apesar da temperatura pouco vari��vel (27,45 �� 0,64��C), houve progressiva diminui����o de salinidade (25 - 15 ), devido ao per��odo de fortes chuvas (34,70 �� 23,78mm). Somado a isso, foram observados v��rios fatores biol��gicos interferindo no viveiro, como a presen��a de ep��fitas, organismos endof��ticos, fouling e a herbivoria por parte dos pr��prios camar��es. Houve aumento nas concentra����es de NH4+ (4,36 �� 1,69 &#956;mol.L-1), NO3- (0,17 �� 0,25&#956;mol.L-1) e PO4-2 (0,41 �� 0,13&#956;mol.L-1), coincidindo com o crescimento da esp��cie at�� a terceira semana. Todos os par��metros ambientais analisados, assim como a biomassa e a Taxa de Crescimento Relativo (TCR), obtidos no campo, apresentaram varia����es altamente significativas (p < 0,001). As correla����es observadas entre biomasa e NH4+ (r = 0,82; p < 0,001) e entre biomassa e PO4-2 (r = 0,87; p < 0,001), indicam que esta esp��cie �� capaz de ter um crescimento satisfat��rio nas condi����es eutr��ficas de um viveiro de camar��o, sendo poss��vel seu uso como biofiltro.

Influ��ncia do lodo de ETE na massa para fabrica����o de cer��mica vermelha

The WTP produce many kinds of residue on your treatment stages, but the sludge is the more problematic from the final disposition point view. The actual rate of residue production deriving from technological evolution and the crescent population needs prevents the subtle equilibrium generation between consumption and recycling/reuse, creating problems of pollution resulting from inappropriate management of residues. Thus, is necessary achieve a new equilibrium between the grow from raw materials and energy and the residue generation. This equilibrium should be achieved by technical and economic feasibility of environmental supported models through recycling and reuse. The red ceramic industry stand out in residue absorption question as raw material due their clay mass heterogeneity, constituted by clay minerals and non-clay minerals with wide mineralogical variation, allowing residue inclusion which act like plastic or non-plastic materials, contributing to retain heavy metals contained in residues in the vitreous mass formed during the burning of the ceramic bodies. This work propose the study of the influence of incorporation of 25 wt.% sludge from wastewater treatment plant, according preliminary results, in the mass to produce ceramic bodies. The raw materials was characterized through chemical composition analyses by XRF, mineralogical analyses by XRD, thermal analyses by TG and DTA, Atterberg limits and thermodilatometry. Subsequently was composed the mass with 75 wt.% of clay and 25 wt.% of dried wastewater sludge from UFRN WWTP. Samples with 6,0 x 2,0 x 0,5 cm was produced with unidirectional compacting under pressure of 20MPa and burned in temperatures between 950 and 1,200��C. After fired, the ceramic bodies have been submitted to physical and mechanical analyses through the measure of firing shrinkage, water absorption, density, apparent porosity and flexural strength; crystallographic analyses through XRD and microstructure analyses by SEM. The technological properties obtained was satisfactory to production of roof tiles with 25 wt.% at 1,200 ��C, but the production of others products at lower temperatures was not feasible

Adsor����o de Pb(II) utilizando adsorvente composto por montmorilonita e dolomita

The destructive impact of improper disposal of heavy metals in the environment increases as a direct result of population explosion, urbanization and industrial expansion and technological developments. Argil are potential materials for adsorption of inorganic and the pelletization of it is required for use in adsorptive columns of fixed bed. The low cost and the possibility of regeneration makes these materials attractive for use in the purification process, capable of removing inorganic compounds in contaminated aquatic environments. In this work was made pellets of a mixture of dolomite and montmorillonite by wet agglomeration, in different percentages. The removal of Pb (II) was investigated through experimental studies, and was modeled by kinetic models and isotherms of adsorption. The materials were characterized using the techniques of XRD, TG / DTA, FT-IR, and surface area by BET method. The results showed the adsorption efficiency of the contaminant by the composite material studied in synthetic solution. The study found that the adsorption follows the Langmuir model, and the kinetics of adsorption follows the model of pseudosecond order