Casimiro Junior

Sugarcane has a significant role on Brazilian agribusiness economy. The harvesting cane is considered as one of the most important operations of the process for it has to attend the raw material demanded by the sugar mill in quality and a competitive cost. The objective of this work it is it of analyzing, of systemic way, the variables influence on economical and operational performance in sugarcane mechanized harvesting process for sizing of machines. For this purpose a model called "ColheCana", was developed in a spreadsheet and in a programming language. The results showed that the field efficiency and harvester´s initial value are variables of great impact in the cost and that there is a maximum area that one equipment can attend and for this area the cost is minimum.

In stored grains, smaller depositions and great variation with respect to theoretical insecticide doses are frequently found. The objective of this work was to study the effectiveness of the standard method (ISO 5682/1-1996) employed to evaluate hydraulic nozzles used in stored corn and wheat grain protection experiments. The transversal volumetric distribution and droplet spectrum of a model TJ-60 8002EVS nozzle were determined in order to calibrate a spraying system for an application rate of 5 L/t and to obtain theoretical concentrations of 10 and 0.5 mg/kg of fenitrothion and esfenvalerate, respectively. After treatment, the corn and wheat grains were processed and deposition was analyzed by gas chromatography. The type of grain did not have any influence on insecticide deposition and was dependent upon insecticide only. The insecticide deposits on the grains only reached 42.1 and 38.2% of the intended theoretical values for fenitrothion and esfenvalerate concentrations, respect...

O objetivo do trabalho foi avaliar a uniformidade de vazão de um pulverizador pneumático costal motorizado, utilizado no controle do mosquito vetor da dengue, sob várias condições operacionais de aplicação. O experimento foi planejado como um delineamento inteiramente casualizado, no esquema fatorial 2 x 7, com cinco repetições, sendo os fatores de variação dois diâmetros de orifício do disco dosador e sete ângulos de aplicação em relação ao plano horizontal. Foi avaliado também o efeito das pressões sobre a vazão por meio dos testes de Pearson. A interação dos fatores diâmetro do orifício do disco dosador e ângulo de aplicação foi significativa para a vazão. O disco dosador com diâmetro de 0,42 mm apresentou maior uniformidade entre as vazões médias, variando de 12,8 a 38,8 mL min-1, para o intervalo de inclinação do ducto aplicador de 60º a -60º e apresentou correlação linear em função do ângulo, com coeficiente de determinação igual a 0,9861. Houve uma expressiva correlação entre...

The presence of insecticide residues in cereals represents a risk for the consumer, because these substances are used in large scale to protect stored grains from the attack of pests. The effects of three processing methods for corn and wheat samples on the stability of stored-grain protective insecticides were here evaluated. Fenitrothion and esfenvalerate were applied so as to produce theoretical concentrations of 10 and 0.5 mg kg-1, respectively. Two hours after treatment, the grains were processed and deposition was analyzed by gas chromatography. Grain species did not influence insecticide stability. This stability was only dependent upon the processing method and insecticide type. Grains processed together with dry ice provided the greatest percentage of recovery for both insecticides. Regardless of the processing method, more esfenvalerate than fenitrothion was recovered, thus demonstrating the greater stability of the pyrethroid during this operation.