Novel electrochemical procedure for the determination of metamitron

In this paper, a chronopotentiometric method for the determination of herbicide metamitron (MTM) using a glassy carbon electrode (GCE) and a thin film mercury electrode (TFME) as working electrodes is presented. MTM provided a well-defined reductive peak in the Britton-Robinson buffer on both working electrodes. Instrumental and chemical factors such as pH of the buffer, initial potential and reduction current influencing MTM chronopotentiometric response were optimised with the Box-Behnken experimental design. Under the optimal combination of factors, the analytical signal was linear in the MTM concentration range of 0.8-30mg/L, with a detection limit of 68.53 mu g/L using a TFME, and in the concentration range of 1-30mg/L, with a detection limit of 92.91 mu g/L using a GCE. The precision of the method was estimated as a function of repeatability and reproducibility, with the value of relative standard deviation lower than 2.6%. The applicability of the method was verified by direct analysis of MTM in spiked water samples and commercial pesticide formulations. The obtained results were in good agreement with those obtained using liquid chromatography/tandem mass spectrometry (LC-MS/MS) method, or with those labelled by the manufacturer. By using chronopotentiometry, neither extraction nor preconcentration procedures are necessary, thus making this method simple, cost-effective and more feasible for analytical routine analysis

Photocatalytic Water Reduction Using a Polymer Coated Carbon Quantum Dot Sensitizer and a Nickel Nanoparticle Catalyst

Hydrogen gas is produced photocatalytically using 470 nm light, PVP-coated carbon quantum dots (CQDs) as the photosensitizer, and nickel nanoparticles (NiNPs) as the catalyst. The effect of the amount of polyvinylpyrrolidone (PVP) on the ability of the CQD/NiNP composites to catalyze proton reduction was studied. A maximum of 330 mmols H2/g CQD is produced using 68 μg ml−1 of CQDs and 6 μg ml−1 of NiNPs, with activity persisting for 4 h when 20 wt%- PVP-coated CQDs were used. The H2 production quantum yield under these conditions is 6%. It was found that composites having higher weight percent PVP had decreased rates of H2 production, but increased duration. Increasing the weight percent of PVP coating also increases the fluorescence quantum yield of CQDs. Fluorescence quenching titrations reveal that H2 production could occur by either a reductive or oxidative quenching mechanism. The nanomaterials, prepared using simple methods, are used as the photosensitizer and catalyst in the proton reduction system that operates using visible light

Standard operational procedure fund distribution system of zakat infaq and shodaqoh for zakat foundations

The management of zakat, infaq and shodaqoh funds is a very crucial activity for each zakat institution, in which two processes are carried out, namely the receipt and distribution of zakat infaq and shodaqoh. This article is the result of further research on the zakat receipt system that was previously published. This fund distribution system is the responsibility of all receipts of funds received so it is very crucial even compared to the ZIS acceptance system itself. This is because there is accountability for the receipt of funds received by the institution and must be submitted to certain parties in accordance with the provisions of Islamic Sharia. Problems that often occur in the process of fund distributing zakat, infaq shodaqoh is a entry data that accountability reports can not be made, the accountability report also can be made, besides that there is also an inaccurate target of the intended recipient distribution object. So that it is necessary to regulate how the right procedures in funds distributing of zakat infaq shodaqoh. The analytical method used by PIECES (Performances, Information, Economics, Control, Efficiency, Services). The standard operating procedure in the ZIS fund distribution system is made with internal control parameters (COSO)