The aim of this work was to determine the presence of organophosphate (OF) and organochlorine (OC) pesticides in forage and milk from dairy farms in the municipality of Pereira (Colombia). The measurement was carried out by means of gas chromatography coupled with tandem mass spectrometry with subsequent confirmation with gas chromatography with electron micro-capture detector. The results indicate the presence of OF and OC in forage and milk at levels higher than those allowed by the Codex Alimentarius and a presence in 90% of the farms, which were exposed to its application days prior to the measurements, especially of OF. The appearance of OC in is related to its persistence in soil, water, in supplements offered to livestock or their application in the area. Pesticides found in forages were not eliminated in the milk of animals that consumed them at levels that were detectable in thi...

This research was conducted in the company Cementos Pacasmayo SAA in the Quality Control Division, during the period between the months January to March 2013, hence its purpose was to reduce the concentration of larger quartz 45 microns present in the crude. This required the development of the application of physical chemical raw quartz, then the contents of greater than 45 microns present in the raw variable quartz grain size was evaluated. This study is justified in that it has a theoretical value - practical behavior of quartz greater than 45 microns in crude, which allowed us to evaluate how feasible it was to continue grinding this without increasing production costs for energy expenditure milling. Furthermore, based on the physicochemical analyzes and empirical evidence. Methodologically the research work will be undertaken from sampling crude type I, until the determination of si...