1,261 research outputs found

    A DBD plasma machine in textile wet processing

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    The conception of new processes for preparation, dyeing and printing of high quality textile products is presented for a brand new technological solution involving a DBD plasmatic discharge in substrates with cellulosic basis. Developments for the machine design and its implementation in production context are discussed. Results in semi-industrial and industrial prototypes are presented giving wide overview for advantages and benefits achieved in fields such as the shortening and preparation steps, the possibility of close combination of preparation and dyeing operations, the elimination of tensioactives in mercerization of the increase in efficiency of finishing agents and extension of durability of effects. High performance finishing and the use of high technology for the improvement and durability of functional properties obtained in natural textiles are proved to be a great contribution to developments in quality, economy and ecology of textile processes. Textile products with a very high added value, able to answer to the existing or coming exigencies of the market, produced by technologies promoting sustainability, can be regarded as a key point to win a future for textile industry

    Micorrizas vesicular-arbusculares em plantas forrageiras - Aspectos agronômicos e interações microbiológicas.

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    Importância e limitações das MVA.Infecção de forrageiras por fungos micorrizicos vesicular-arbusculares (FMVA). Seleção de MVA para forrageiras.Simbiose leguminosa + FMVA + Rhizobium. Efeito de agrotóxicos na simbiose FMVA+Rhizobium+ leguminosa.Efeito de FMVA na nodulação e FBN em leguminosas. Competição da tríplice simbiose por fotossintatos.bitstream/CNPAB-2010/27197/1/doc007.pd

    Quality improvement and shortcut of preparation of CORONA discharged cotton fabrics

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    Textile industry has an important impact in world economy and consequently on environmental quality of life. Textile processing uses huge amount of water, chemicals and energy and it is quite easy to conclude about the enormous meaning of pollution control and rationalization of energetic demands. CORONA treatment in the wet processing of cotton textile materials has a great potential concerning the improvement of all the operations included in it, namely in preparation, dyeing, printing or final finishing. Physical and chemical surface changes in cotton structure are noticed after CORONA discharge. The increase in oxidation potential and the creation of channels through cuticle are referred as responsible for the variation in cotton properties after plasmatic discharge, specially concerning absorption of water and treatment baths. Advantages as the use of less chemicals, namely alkalis, oxidants and other auxiliaries, the reduction of times and temperatures, less damages in the materials surely can have a strong impact in economical and ecological aspects of the process. Complete hidrophilization of cellulosic materials renders very easy the access of baths and consequently conditions to more efficient operations are found. Bleaching processes aim to give textile materials the adequate whiteness degree, the removal of sizing agents, the increase of hidrophility and cleaning by extraction of seeds, husks and waxes. The use of hydrogen peroxide in alkaline medium is a flexible and more ecological process when compared with methods based in chlorinated compounds. The present work concerns the study of half bleaching process when this operation is preceded by a CORONA discharge made on dry grey fabrics. The influence in the whiteness degree, hidrophility, starch removal and uniformity of properties of the cellulosic material after preparation is studied

    Developments in preparation and dyeing of CORONA discharged cellulosic materials

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    The preparation and dyeing of cellulosic fabrics hás important problems such as uniformity of aspect, cleaning efficiency, level of bleaching, conformity and fastness of colours, and ecological impact. Combination of preparation processes can give optimal solutions, regarding economy and ecology, especially if superior quality items are achieved in final products. In fact, high standards concerning whiteness, starch removal and hidrophilicity are considered a good basis for leveled, cleaner and intense dyeing. A better white basis, escellent hidrophilicity and enough removal of impurities are obtained if desizing is omitted and a CORONA discharge is made over dry grey material. Exhaustion dyeings with different classes of direct dyes show similar behavior concerning the positive influence of the discharge in the intensity of colours and their fastness. Good penetration of dyes in coronised cotton materials is assured and consequently a good fastness is abtained

    Improvement of durable properties of surgical textiles using plasma treatment

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    Nowadays one of the important plasmas used in textile industry is Corona discharge, which is applied in air at atmospheric pressure. Corona offers many advantages such as low production costs mainly due to effective energy utilization and minimum waste materials. In this study, the main focus is to use Corona plasma to produce reusable surgical fabrics with durable properties and using chemical agents at low concentrations. Therefore a new more economic production process of surgical fabric will be offered to textile industry. In order to evaluate the effect of Corona discharge on liquid repellent finishing durability, surface energy was determined by using dynamic contact angle measurement of fabrics treated and non-treated with Corona then finished with products based on fluorocarbons after successive washings. Results showed that Corona increases, significantly, durability of finishing on the fabric. After five washings at 60 ºC, samples pre-treated with Corona at low power levels and finished at lower concentrations preserved their water repellent properties while samples non-treated with Corona and finished with high concentrations lost their affects. To study water resistance, Impact Penetration Test was applied to determine water repellency before and after several washings. The fabrics pre-treated with Corona, after twenty washings, had better effect than samples non-treated after five washings. All results show that Corona improves performance and durability of finishing products. In addition, the fabrics treated and non-treated with Corona and finished by nano-size silver product were analysed before and after washings to determine the effect of Corona on durability of antibacterial finishing

    Assessment of iron and nitrates concentration in drinking water, in the district of Bragança, Portugal between 2012 and 2013

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    Water is an essential resource for life. It is a crucial factor for all living beings’ survival thus, it is necessary to promote means to obtain drinking water for human consumption.1 The water intended for human consumption, according to the World Health Organization (WHO),is quality water as soon as it does not cause a significant threat to human health during its consumption.2 The diseases related to the contamination of water for human consumption constitute a very high responsibility and importance to the Public Health. The nitrates have a high solubility and may reach the groundwater in the deep layers of the soil by processes as leaching, particularly in areas with intensive farming and livestock. High concentrations of nitrates can be very harmful to human health since they can be easily converted into nitrites which concentrations cannot exceed the parametric value of 50 mg/L in water for human consumption (Dec. Law n.º 306/2007). The greater effect of nitrite in human health is your involvement in the oxidation of hemoglobin (Hb) to methemoglobin (MetHb). High concentrations of nitrates cause severe methaemoglobinemia in infants and adults. The methemoglobinemia is a rare condition caused by excessive conversion of hemoglobin (Hb) in methemoglobin (MetHb), being unable to bind and transport oxygen.3The iron exists in low concentrations in natural waters and usually its presence results of processes such as leaching of soils or industrial pollution. The presence of iron in the water can consequently cause the corrosion of metal pipes or the use of iron salts as agents of coagulation/flocculation in water treatment and the parametric value of iron is 200μg/L (Dec. Law n.º 306/2007) in water for human consumption.The objective of this study was to evaluate the concentration of nitrate and iron in drinking water in the district of Bragança in order to identify the sampling point that keeps concentrations of these ions above the parametric values.The collection of drinking water samples in the district of Bragança occurred between the years of 2012 and 2013, with subsequent spectrophotometric determination of nitrate and iron concentration, in the Public Health Laboratory of Bragança (PHLB).Samples with concentrations above the parametric values were identified: above 200 μg/L to iron and above 50 mg/L to nitrates (Dec, Law n.º 306/2007). The collected data was statistically treated in program Microsoft Office - Excel and the analysis of the data was carried out using the normal distribution with levels of confidence of 95 %. In the year 2012 were collected 624 samples and 8.8% of these were outside the parametric values with 8.7% corresponding to samples with values of increased iron and 0.1% corresponding to increased nitrate’s values. In the year 2013 it was collected 1208 samples in which 8.9% were above the parametric values stipulated, from which 8.6% corresponded to samples with increased concentrations of iron and 0.3% corresponded to samples with nitrate levels above the parametric values. Two regions exhibited a greater number of samples with concentrations above the established limits for the parameters studied in this work. One of the regions had 15.9% of the samples above the established limits and the other had 12.6%.Individuals that consumed this water with high levels of iron and nitrates may be associated with several potential health threat

    O Eixo Atlántico: un territorio educador, unha comunidade educativa

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    Eixo Atlântico do Noroeste PeninsularEixo Atlântico do Noroeste Peninsularinfo:eu-repo/semantics/publishedVersio

    Impact of Lipodystrophy on the prevalence and components of metabolic syndrome in HIV-infected patients

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    BACKGROUND: In HIV-infected patients, combination antiretroviral therapy (cART) is associated with clinical lipodystrophy (CL) and metabolic abnormalities (MA). This study aimed to evaluate the prevalence of the metabolic syndrome (MS) and its components, and to determine whether patients with or without CL had a different prevalence of MA. METHODS: We evaluated 345 HIV-infected patients on cART using two different MS definitions (NCEP-ATPIII-2005 and IDF-2005) and the Framingham risk score. RESULTS: CL was present in 58.7% of the patients. The prevalence of the MS was 52.2% (ATPIII) and 43.2% (IDF), and it was not significantly different between patients with (W) or without (WT) CL, regardless of the definition used (ATPIII WCL 52.9% vs WT CL 51.1%; p = 0.738; IDF WCL 41.3% vs WTCL 46.0%; p = 0.379). Moderate concordance was observed between the 2 definitions (kappa = 0.484; p < 0.001) and after gender stratification there was good concordance in women (kappa = 0.759; p < 0.001). Patients with CL had lower waist circumference and HDL-C and higher triglycerides levels. In women, CL was significantly associated with MS, hypertriglyceridemia and low HDL cholesterol independently of age, cART and BMI. Patients with CL had a significantly higher risk of coronary heart disease at 10 years, measured by the Framingham risk score, than patients without CL. Those with CL and with MS had higher frequencies of moderate and high risk categories than those without MS. CONCLUSIONS: The prevalence of the MS was high in these HIV-infected patients with an age average of 40 years and this finding could explain why HIV patients have an increased risk for cardiovascular disease (CVD)
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