EFFECT OF MECHANICAL ACTIVATION ON THE POTASSIUM AVAILABILITY OF PHONOLITE ROCK
Background: Researchers are carried out to assess rocks containing potassium as an alternative source of fertilizers. These studies are important in reducing the external dependence of Brazil on this commodity. Phonolite is a rock of volcanic origin that has in its mineralogical composition the predominance of feldspar and has been potential to use as an alternative potassium source. The studied rock has 6% total-K but is unavailable to plants in natural rock. Aim: This project evaluated the effect of mechanical activation, wet and dry, on K availability for extractors different and its K leaching curves of phonolite from Poços de Caldas, MG, Brazil. Methods: Phonolite rock was subjected to mechanical activation for 30 and 60 min by wet and dry processes. Particle size distribution, XRD, and FTIR analyses characterized phonolite activated. These results were compared to the behavior of the rock with no activation. K availability (total; water-soluble; exchangeable, non-exchangeable, and structural) was determined in samples activated and no activation. K leaching curves were obtained by successive extractions with 0.01 mol L-1 citric acid and Mehlich-1 solutions to 1812 h and analyzed by FAAS. Results: The samples mechanical activation promoted a reduction in the intensity of the diffraction peaks. In the sample dry mechanical activation for 60 min, K released increased by 15% in relation to the no activation sample. K leaching curves were observed with similar behavior for the extractors and higher K availability after 235 h of total contact time. Discussion: Mechanical activation promoted a decrease in structural K and an increase in non-exchangeable K, released into the soil solution in the medium term. Since the mineralogical composition was not changed, the process action is more efficient in creating the structural defects suggested. K leaching curves corroborate these results, with a continuous and slow K released for a longer contact time. Conclusions: It was concluded that the phonolite activated by dry mechanical activation for 60 min increased K-released content compared with the wet process and ratified the possibility of the activated phonolite rock as a slow-release fertilizer.
Read ArticleMANAGEMENT MODEL FOR CONSTRUCTION WASTE PRODUCED IN THE CITY OF RIO DE JANEIRO
Background: A new management model for construction and demolition waste (CDW) was proposed for the city of Rio de Janeiro, hence waste the city planning area estimated generation; the results were compared with the data published by COMLURB and SNIS through the statistics tests was proved that CDW had been dispersed, which support the hypothesis that the current model cause dispersion of the rubble. Aim: This study proposes a new management model for CDW to the city, according to regions where occur the higher production of rubble. Methods: The estimation of rubble was obtained through the issued licenses from 2006 to 2020 published by SMPU. The quantification of rubble in the city was carried out by adopting the generation indicator from licensed construction activities. The amount of CDW published by COMLURB and SNIS was compared through statistics tests ANOVA and T-Test, the second period from 2006 to 2020 and 2011 to 2020. To measure the area to implant a CDW recycling plant, criteria from production capacity were used. Results: ANOVA test to data from 2006 to 2020 and 2011 to 2020, according to a confidence interval of 95%, found the P value 0.589 and 0.022, respectively, it was verified that the significant difference is between data from COMLURB and Estimated. The T-test was applied from the same period in data from SNIS and estimated the P values 0.399 and 0.014. Discussion: The data from Estimating between 2006 and 2020 showed the best representation. The Área de Planejamento – AP (Planning Area) 4 was where 50.70% of the total rubble, after the AP 3 with 17.66%, the AP 5 was estimated at 16.59%, last of all, AP 2 and AP 1 were calculated the generation of 8.28% and 6.77%, respectively. Therefore, sizing the CDW recycling producing 361,99.00 tons per year demands an area of 32,397.50 m². Conclusions: It was concluded that the receipt of CDW in transfer stations managed by COMLURB is not allowed; therefore, the need to create a construction waste recycling plant was presented, to this end, it is necessary to have an available area of approximately 32,397.50 m².
Read ArticleUTILIZATION OF PROTEOMICS APPROACH TO UNDERSTAND GENES ASSOCIATED WITH THE OCCURRENCE OF BIOTIC STRESS IN PLANTS
Of the most fundamental fields of modern biology is transcriptomics, with a focal point on the expression pattern of plants under various conditions by assessing ribonucleic acid. So far, this approach has been a game-changer in revealing the gene structure, function, and most importantly, their cellular and biological role. Considering the criticality of pathogens for crop plants, understanding plant defense mechanisms against them is in high demand. This study aimed to review the principles of these approaches and their recent application in the plant. An Important method to address this gap is transcriptomics, which can effectively provide insight into plants against pathogens. This field has covered different aspects of plant biology besides the plant-pathogen relationship. Identifying pathogens in infected plants and the series of reactions they provoke at the gene level is crucial to finding the responsible gene (s). Finding the gene associated with resistance or vulnerability to a specific pathogen paves the way to differentiate the potential genotypes. Thus, the breeding attempts would be more successful. The advancement in biotechnology has revolutionized this field with some of the methods that have been commonly applied in studies on the plant-pathogen relationship, for instance, Northern blotting, microarray, real-time polymerase chain reaction.
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