Multiresidue analysis of pesticides in fruits and vegetables by gas chromatography-mass spectrometry

A multiresidue method was assessed for the determination of several pesticides (organochlorine, organophosphorus, pyrethroids, triazole, amidine) using gas chromatography/mass spectrometry. The extraction of pesticides was carried out by liquid-liquid extraction (LLE) and solid-phase extraction (SPE) using two types of columns (CN and C18). The extracts were cleaned by the addition of florisil, the pesticides were separated by capillary column gas chromatography and detected by mass spectrometry in the electron impact mode. The extraction using C18 column provided the best results for most of the analyzed pesticides. The majority of pesticides recoveries from the four fruits and vegetables (apples, pears, tomatoes and pepper) were greater than 60%. Linearity and precision were satisfactory. The estimated limits of detection and limits of quantification ranged from 0.01 to 0.1 mg/kg and from 0.02 to 0.3 mg/kg, respectively. The proposed procedure was found to be useful for the multiresidue analyses of pesticides in agricultural products for routine monitoring programs.     

Effect of Zn salts and hydrolyzing agents on the morphology and antibacterial activity of zinc oxide nanoparticles

Environmental Chemistry Letters - Zinc oxide nanoparticles (ZnONPs) are considered safe as antibacterials. Those nanoparticles should preferably have uniform size and shape, but conditions to...     

Mechanical characteristics evaluation of biogas micro turbine power systems

As the increase of energy demand, the emission of CO2 is also likely to increase by at least the same amount because energy supply will be based on fossil fuels, which is more apparent in a number of developing countries. With the total global energy environment and rapid increase of domestic and foreign demand, renewable energy is the inevitable energy source for the future. In this context, the micro gas turbines (MGTs) by using bio-energy is being considered as a promising solution. In order to develop the real plant system of those technologies such as 60 kW-class micro gas turbine by using swine biogas, we finished the optimal design and construction for a biomass fueled MGT system. This paper consists of 1) MGT system design for swine bio gas 2) material evaluation for bio gas piping 3) computational fluid dynamics analysis for bio gas sulfur removal tower and sulfur absorption filter 4) the fundamental modeling using manufacturer's technical specifications and performance simulation by PEPSE-GT 5) field test and application of bio gas micro gas turbine. Finally, I established to set up the top-notched distributed power system design and optimal application.     

Multiresidue analysis of pesticides in fruits and vegetables by gas chromatography-mass spectrometry

A multiresidue method was assessed for the determination of several pesticides (organochlorine, organophosphorus, pyrethroids, triazole, amidine) using gas chromatography/mass spectrometry. The extraction of pesticides was carried out by liquid-liquid extraction (LLE) and solid-phase extraction (SPE) using two types of columns (CN and C18). The extracts were cleaned by the addition of florisil, the pesticides were separated by capillary column gas chromatography and detected by mass spectrometry in the electron impact mode. The extraction using C18 column provided the best results for most of the analyzed pesticides. The majority of pesticides recoveries from the four fruits and vegetables (apples, pears, tomatoes and pepper) were greater than 60%. Linearity and precision were satisfactory. The estimated limits of detection and limits of quantification ranged from 0.01 to 0.1 mg/kg and from 0.02 to 0.3 mg/kg, respectively. The proposed procedure was found to be useful for the multiresidue analyses of pesticides in agricultural products for routine monitoring programs.     

Sulfur recycling into value-added materials: a review

Environmental Chemistry Letters - About 70 million tons of sulfur are produced yearly as a by-product of petroleum refining, and 10 millions are overproduced and accumulated, thus requiring...     

Synthesis,properties and food packaging applications of sulfur quantum dots: a review

Environmental Chemistry Letters - About one billion tons of food is wasted annually due to microbial contamination and oxidative deterioration. Actually, this issue is solved by hazardous and...