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101.
In this study, the viability of using electrostatic painting residues--paint sludge--as a raw material to the red clay industry was investigated. Red clay-based ceramic masses containing electrostatic paint residues were formulated during the study. The clays were obtained from the Rio do Rastro deposit, in Gravataí, and were of the standard formulation used in industry. Different ceramic mass formulations with additions of 0.5, 1.0, 2.5 and 5.0 wt.% electrostatic painting residue in addition to a formulation with no residue addition (standard formulation), were evaluated. The samples were uniaxially pressed in a double-effect press and were fired in an electric oven at 900, 950 and 1000 degrees C. The firing at constant temperature lasted 8 h, and heating rate was 150 K h(-1). After processing the samples were characterized in terms of their physical and mechanical properties. Environmental compatibility was also considered by the evaluation of gaseous emissions and leaching and solubilization tests according to the Brazilian standards NBR 10.005 and NBR 10.006, respectively. The results showed that it was possible to produce ceramic materials containing electrostatic painting residues within their formulations.  相似文献   
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103.
Environment, Development and Sustainability - The objective of this work was to analyse the relations between innovation management and organisational sustainability in a Brazilian higher education...  相似文献   
104.
Energy and Carbon Embodied in the International Trade of Brazil   总被引:4,自引:0,他引:4  
Shifting the economicstructure of a country towardsenergy-intensive industries may lead tosignificant effect on the environment. Oneof the major environmental impactsassociated to such changes is the increaseof the Carbon Dioxide emissions – the mainfactor behind the greenhouse effect. In thelast decades, structural changes in theBrazilian economy were close related tochanges in the country's tradespecialization. This paper analyzes to whatextent energy use and its associatedCO2 emissions of Brazil in the 90's maybe overloaded by changes in the country'strade specialization towards a moreenergy-intensive mix. This study finds thatBrazil exported, in net terms, significantamounts of energy and carbon (C) embodied ingoods traded with the rest of the world inthe 90's. In fact, some 6.6% of the finalenergy used by the industrial sector andaround 7.1% of its C emissions areprompted by international trade. Byoverloading the country's energy use andits associated environmental damage (bothlocal and global), this situation seems tocontribute to increase not only local butalso global environmental damage, sinceC leakage from non-Annex I countriesdue to international trade may lead tohigher C concentration in theatmosphere.  相似文献   
105.
After an exhaustive investigation, in 1997 the source of the milk contamination in Germany was traced to citrus pulp pellets originating from Brazil. It has been shown that lime was the source of the PCDD/F contamination of these products. After this conclusion, a continuous monitoring program has been performed over a two year period and the results are presented in this paper. Standard isotope dilution techniques were used for all samples, which were analyzed by selected ion monitoring high resolution GC–MS.  相似文献   
106.
Population dynamics of weeds in successive maize and bean crops were evaluated in two soil management systems (conventional and no-tillage), for two maize applications (grain and silage), and in four consecutive growing seasons. Every year, conventional tillage consisted in plowing and harrowing before sowing. In no-tillage, chemical weed desiccation was made with the mixture glyphosate + 2.4-D. To control weeds, the mixture fluazifop-p-butil + fomesafen was applied on the bean crop in all the planting seasons, and the herbicides nicosulfuron + atrazine on maize after crop emergence (1998--1999, 1999--2000, 2001--2002) and atrazine + metolachlor before emergence (2000--2001). Purple nutsedge (Cyperus rotundus) was the most important species under conventional soil tillage; while in no-tillage the dicotyledonous weed species (Amaranthus deflexus, Bidens pilosa, Euphorbia heterophylla, Galinsoga parviflora Ipomoea grandifolia) were the most relevant. Regardless of the maize use, the C. rotundus population and tuber bank, with prevailingly dormant tubers, was considerably reduced in no-tillage compared with the conventional system.  相似文献   
107.
Foodborne transmission gastroenteritis (AGE) outbreak occurred during a celebration lunch in July, 2016, Brazil. All stool samples tested were positive for noroviruses (NoV) and phylogenetic analysis revealed that strains were genetically close to GII.17 Kawasaki_2014. These findings indicated circulation of NoV GII.17 Kawasaki_2014 in the Brazilian population, associated with AGE outbreak.  相似文献   
108.
Gemycircularvirus (GemyCV) is a group of viruses which has been recently proposed as a new viral genus detected in fecal and environmental samples around the world. GemyCVs have been detected in human blood, brain tissue, cerebrospinal fluid, and stool sample. In the present study, we demonstrate for the first time, through molecular detection and characterization, the presence of GemyCVs in environmental samples from Brazil. Our results show a percentage of positivity ranging from 69 (25/36) to 97 % (35/36) in river water samples collected in Manaus, Amazon region, and wastewater from a wastewater treatment plant located in Rio de Janeiro, respectively, revealing GemyCVs as an important environmental contaminant.  相似文献   
109.
The radioactivity level of soils in a volcanic area in Cameroon was determined and discussed. Thirty soils samples were collected from Buea and Limbé cities located in the south-western Cameroon. These two regions are known for theirs volcanic grounds due to the presence of Mount Cameroon Mountain. The activity concentrations of natural radionuclides as well as that of the fission product were evaluated by gamma-ray spectrometry using a hyper-purity germanium detector (HPGe). The ranges of concentrations in the surveyed soils were 11-17 Bq kg(-1), 22-36 Bq kg(-1) and 43-201 Bq kg(-1) for (226)Ra, (232)Th and (40)K, respectively. The radioisotope (137)Cs was also found but in a very small amount. The outdoor absorbed dose rate 1m above ground with the corresponding annual effective dose rate, assuming a 20% occupancy factor was estimated. The radium equivalent and the external hazard index were also evaluated and results are compared with available data from other studies and with the world average value [United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), 1988. Sources, Effects and Risks of Ionizing Radiation. Report to the General Assembly on the Effects of Atomic Radiation. United Nations, New York; UNSCEAR, 2000. Sources and Effects of Ionizing Radiations. Report to the General Assembly with Scientific Annexes. United Nations, New York]. A solid state nuclear track detector (SSNTD), LR-115 was used for soil radon measurements at a depth of 50 cm. The ranges of soil radon concentrations were 6.7-10.8 kBq m(-3) and 5.5-8.7 kBq m(-3) in Buea and Limbé, respectively. A positive correlation was found between concentrations of radium measured with gamma-spectrometry and the soil radon concentrations measured with the nitrate cellulose detectors. The results of this study provide the radioactivity level in soil of a volcanic area, which has been found to be within the safety limits. The south-western Cameroon can be considered as having normal natural background radiation.  相似文献   
110.
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